ORCID Profile
0000-0002-1552-6166
Current Organisation
UNSW Sydney
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Hydrogeology | Quaternary Environments | Physical Geography and Environmental Geoscience | Isotope Geochemistry | Geochemistry | Inorganic Geochemistry | Geomorphology and Regolith and Landscape Evolution | Organic Geochemistry | Climate Change Processes | Surfacewater Hydrology | Water Quality Engineering | Palaeoclimatology | Environmental Science and Management | Chemical Spectroscopy | Atmospheric Sciences | Civil Engineering | Atmospheric Dynamics | Physical Oceanography | Cloud Physics | Climatology (excl. Climate Change Processes) | Water And Sanitary Engineering | Environmental Monitoring | Water Treatment Processes |
ANZSRC Socio-Economic Objective (SEO)
Physical and Chemical Conditions of Water in Fresh, Ground and Surface Water Environments (excl. Urban and Industrial Use) | Effects of Climate Change and Variability on Australia (excl. Social Impacts) | Climate Variability (excl. Social Impacts) | Climate Change Models | Water Allocation and Quantification | Forest and Woodlands Soils | Ecosystem Adaptation to Climate Change | Ecosystem Assessment and Management of Fresh, Ground and Surface Water Environments | Climate Change Mitigation Strategies | Climate Change Adaptation Measures | Atmospheric Processes and Dynamics | Land and Water Management of environments not elsewhere classified | Natural Hazards in Fresh, Ground and Surface Water Environments | Urban Water Evaluation (incl. Water Quality) | Physical and Chemical Conditions of Water for Urban and Industrial Use | Global Effects of Climate Change and Variability (excl. Australia, New Zealand, Antarctica and the South Pacific) (excl. Social Impacts) | Expanding Knowledge in the Earth Sciences | Public health not elsewhere classified | Electricity, gas and water services and utilities | Forest and Woodlands Land Management | Rural Water Evaluation (incl. Water Quality)
Related Links
Publications
Precise dating of Dansgaard–Oeschger climate oscillations in western Europe from stalagmite data
Publisher: Springer Science and Business Media LLC
Date: 02-2003
DOI: 10.1038/NATURE01391
Supplementary material to "The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems"
Publisher: Copernicus GmbH
Date: 16-04-2018
Hydrological uncertainties in the modelling of cave drip-water δ18O and the implications for stalagmite palaeoclimate reconstructions
Publisher: Elsevier BV
Date: 08-2010
Quantifying temporal variability and spatial heterogeneity in rainfall recharge thresholds in a montane karst environment
Publisher: Elsevier BV
Date: 03-2021
A post-wildfire response in cave dripwater chemistry
Publisher: Copernicus GmbH
Date: 21-07-2016
DOI: 10.5194/HESS-20-2745-2016
Abstract: Abstract. Surface disturbances above a cave have the potential to impact cave dripwater discharge, isotopic composition and solute concentrations, which may subsequently be recorded in the stalagmites forming from these dripwaters. One such disturbance is wildfire however, the effects of wildfire on cave chemistry and hydrology remains poorly understood. Using dripwater data monitored at two sites in a shallow cave, beneath a forest, in southwest Australia, we provide one of the first cave monitoring studies conducted in a post-fire regime, which seeks to identify the effects of wildfire and post-fire vegetation dynamics on dripwater δ18O composition and solute concentrations. We compare our post-wildfire δ18O data with predicted dripwater δ18O using a forward model based on measured hydro-climatic influences alone. This helps to delineate hydro-climatic and fire-related influences on δ18O. Further we also compare our data with both data from Golgotha Cave – which is in a similar environment but was not influenced by this particular fire – as well as regional groundwater chemistry, in an attempt to determine the extent to which wildfire affects dripwater chemistry. We find in our forested shallow cave that δ18O is higher after the fire relative to modelled δ18O. We attribute this to increased evaporation due to reduced albedo and canopy cover. The solute response post-fire varied between the two drip sites: at Site 1a, which had a large tree above it that was lost in the fire, we see a response reflecting both a reduction in tree water use and a removal of nutrients (Cl, Mg, Sr, and Ca) from the surface and subsurface. Solutes such as SO4 and K maintain high concentrations, due to the abundance of above-ground ash. At Site 2a, which was covered by lower–middle storey vegetation, we see a solute response reflecting evaporative concentration of all studied ions (Cl, Ca, Mg, Sr, SO4, and K) similar to the trend in δ18O for this drip site. We open a new avenue for speleothem science in fire-prone regions, focusing on the geochemical records of speleothems as potential palaeo-fire archives.
Hydroclimate of the Last Glacial Maximum and deglaciation in southern Australia's arid margin interpreted from speleothem records (23-15 ka)
Publisher: Copernicus GmbH
Date: 14-06-2017
Abstract: Abstract. Terrestrial data spanning the Last Glacial Maximum (LGM) and deglaciation from the southern Australian region are sparse and limited to discontinuous sedimentological and geomorphological records with relatively large chronological uncertainties. This dearth of records has hindered a critical assessment of the role of the Southern Hemisphere mid-latitude westerly winds on the region's climate during this time period. In this study, two precisely dated speleothem records for Mairs Cave, Flinders Ranges, are presented, providing for the first time a detailed terrestrial hydroclimatic record for the southern Australian drylands during 23–15 ka. Recharge to Mairs Cave is interpreted from the speleothem record by the activation of growth, physical flood layering, and δ18O and δ13C minima. Periods of lowered recharge are indicated by 18O and 13C enrichment, primarily affecting δ18O, argued to be driven by evaporation of shallow soil/epikarst water in this water-limited environment. A hydrological driver is supported by calcite fabric changes. These include the presence of laminae, visible organic colloids, and occasional dissolution features, related to recharge, as well as the presence of sediment bands representing cave floor flooding. A shift to slower-growing, more compact calcite and an absence of lamination is interpreted to represent reduced recharge. The Mairs Cave record indicates that the Flinders Ranges were relatively wet during the LGM and early deglaciation, particularly over the interval 18.9–15.8 ka. This wetter phase ended abruptly with a shift to drier conditions at 15.8 ka. These findings are in agreement with the geomorphic archives for this region, as well as the timing of events in records from the broader Australasian region. The recharge phases identified in the Mairs Cave record are correlated with, but antiphase to, the position of the westerly winds interpreted from marine core MD03-2611, located 550 km south of Mairs Cave in the Murray Canyons region. The implication is that the mid-latitude westerlies are located further south during the period of enhanced recharge in the Mairs Cave record (18.9–16 ka) and conversely are located further north when greater aridity is interpreted in the speleothem record. A further comparison with speleothem records from the northern Australasian region reveals that the availability of tropical moisture is the most likely explanation driving enhanced recharge, with further lification of recharge occurring during the early half of Heinrich Stadial 1 (HS1), possibly influenced by a more southerly displaced Intertropical Convergence Zone (ITCZ). A rapid transition to aridity at 15.8 ka is consistent with a retraction of this tropical moisture source.
Estimation of deep infiltration in unsaturated limestone environments using cave lidar and drip count data
Publisher: Copernicus GmbH
Date: 20-01-2016
Abstract: Abstract. Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management, and for stalagmite-based paleoclimate reconstructions. Caves offer a natural inception point to observe both the long-term groundwater recharge and the preferential movement of water through the unsaturated zone of such limestone. With the availability of automated drip rate logging systems and remote sensing techniques, it is now possible to deploy the combination of these methods for larger-scale studies of infiltration processes within a cave. In this study, we utilize a spatial survey of automated cave drip monitoring in two large chambers of Golgotha Cave, south-western Western Australia (SWWA), with the aim of better understanding infiltration water movement and the relationship between infiltration, stalactite morphology, and unsaturated zone recharge. By applying morphological analysis of ceiling features from Terrestrial LiDAR (T-LiDAR) data, coupled with drip time series and climate data from 2012 to 2014, we demonstrate the nature of the relationships between infiltration through fractures in the limestone and unsaturated zone recharge. Similarities between drip rate time series are interpreted in terms of flow patterns, cave chamber morphology, and lithology. Moreover, we develop a new technique to estimate recharge in large-scale caves, engaging flow classification to determine the cave ceiling area covered by each flow category and drip data for the entire observation period, to calculate the total volume of cave discharge. This new technique can be applied to other cave sites to identify highly focussed areas of recharge and can help to better estimate the total recharge volume.
Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia
Publisher: Copernicus GmbH
Date: 06-06-2017
Abstract: Abstract. Cave drip water response to surface meteorological conditions is complex due to the heterogeneity of water movement in the karst unsaturated zone. Previous studies have focused on the monitoring of fractured rock limestones that have little or no primary porosity. In this study, we aim to further understand infiltration water hydrology in the Tamala Limestone of SW Australia, which is Quaternary aeolianite with primary porosity. We build on our previous studies of the Golgotha Cave system and utilize the existing spatial survey of 29 automated cave drip loggers and a LiDAR-based flow classification scheme, conducted in the two main chambers of this cave. We find that a daily s ling frequency at our cave site optimizes the capture of drip variability with least possible s ling artifacts. Most of the drip sites show persistent autocorrelation for at least a month. Drip discharge histograms are highly variable, showing sometimes multimodal distributions. Histogram skewness is shown to relate to the wetter than average 2013 hydrological year and modality is affected by seasonality. Finally, a combination of Multi-dimensional scaling (MDS) and clustering by k-means is used to classify similar drip types based on time series analysis. This clustering reveals four unique drip regimes which agree with the flow type classification of Mahmud et al. (2016) for this site. It highlights a spatial homogeneity in drip types in one cave chamber, and spatial heterogeneity in the other, which is in concordance with our understanding of cave chamber morphology and lithology. Our hydrological classification scheme with respect to mean discharge and the flow variation, can distinguish between groundwater flow types in limestones with primary porosity, and the technique could be used to characterize different karst formations when high-frequency automated drip logger data are available. We observe little difference in the Coefficient of variation (COV) between flow classification types, probably reflecting the dominance of primary porosity at this cave site, and the seasonal variations in discharge related to storage replenishment in winter followed by recession in the periods of soil moisture deficit. Moreover, we do not find any relationship between drip variability and discharge within similar flow type.
Millennial-length forward models and pseudoproxies of stalagmite δ<sup>18</sup>O: an example from NW Scotland
Publisher: Copernicus GmbH
Date: 11-07-2012
Abstract: Abstract. The stable oxygen isotope parameter δ18O remains the most widely utilised speleothem proxy for past climate reconstructions. Uncertainty can be introduced into stalagmite δ18O from a number of factors, one of which is the heterogeneity of groundwater flow in karstified aquifers. Here, we present a lumped parameter hydrological model, KarstFor, which is capable of generating monthly simulations of surface water – ground water – stalagmite δ18O for more than thousand-year time periods. Using a variety of climate input series, we use this model for the first time to compare observational with modelled (pseudoproxy) stalagmite δ18O series for a site at Assynt, NW Scotland, where our knowledge of δ18O systematics is relatively well understood. The use of forward modelling allows us to quantify the relative contributions of climate, peat and karst hydrology, and disequilibrium effects in stalagmite δ18O, from which we can identify potential stalagmite δ18O responses to climate variability. Comparison of the modelled and actual stalagmite δ18O for two stalagmites from the site demonstrates that, for the period of overlapping growth, the two series do not correlate with one another, but forward modelling demonstrates that this falls within the range explicable by differences in flow routing to the stalagmites. Pseudoproxy δ18O stalagmite series highlight the potential significance of peat hydrology in controlling stalagmite δ18O over the last 1000 yr at this site.
Characterisation of shallow groundwater dissolved organic matter in aeolian, alluvial and fractured rock aquifers
Publisher: Elsevier BV
Date: 03-2020
RADIOCARBON PROTOCOLS AND FIRST INTERCOMPARISON RESULTS FROM THE CHRONOS 14CARBON-CYCLE FACILITY, UNIVERSITY OF NEW SOUTH WALES, SYDNEY, AUSTRALIA
Publisher: Cambridge University Press (CUP)
Date: 11-05-2021
DOI: 10.1017/RDC.2021.23
Abstract: The Chronos 14 Carbon-Cycle Facility is a new radiocarbon laboratory at the University of New South Wales, Australia. Built around an Ionplus 200 kV MIni-CArbon DAting System (MICADAS) Accelerator Mass Spectrometer (AMS) installed in October 2019, the facility was established to address major challenges in the Earth, Environmental and Archaeological sciences. Here we report an overview of the Chronos facility, the pretreatment methods currently employed (bones, carbonates, peat, pollen, charcoal, and wood) and results of radiocarbon and stable isotope measurements undertaken on a wide range of s le types. Measurements on international standards, known-age and blank s les demonstrate the facility is capable of measuring 14 C s les from the Anthropocene back to nearly 50,000 years ago. Future work will focus on improving our understanding of the Earth system and managing resources in a future warmer world.
Supplementary material to "The evolution of stable silicon isotopes in a coastal carbonate aquifer, Rottnest Island, Western Australia"
Publisher: Copernicus GmbH
Date: 08-10-2020
Thermal fluorescence quenching properties of dissolved organic matter
Publisher: Elsevier BV
Date: 11-2005
DOI: 10.1016/J.WATRES.2005.08.023
Abstract: The fluorescence excitation-emission matrices of dissolved organic matter (DOM) are investigated between 10 and 45 degrees C for river and waste waters and organic matter standards. With increased temperature, fluorescence intensity is quenched. It is demonstrated that for a range of river and wastewater s les, that tryptophan-like fluorescence exhibits a greater range of quenching (between 20+/-4% and 35+/-5%) than fulvic-like fluorescence (19+/-4 to 26+/-3%) over this temperature range. Humic substance standards exhibit similar fulvic-like (23+/-4%) fluorescence thermal quenching properties to river water s les (23+/-3%) however none of the s les exhibit quenching of tryptophan-like fluorescence to the same extent as the tryptophan standards (approximately 50%). Thermal fluorescence quenching is related to the exposure of the fluorophores to the heat source our findings suggest that the tryptophan-like groups within DOM is more exposed in untreated wastewaters than in treated wastewaters riverine DOM. Thermal fluorescence properties have the potential to be used to source DOM, to provide additional chemical structural information, to temperature correct laser-induced remotely sensed DOM fluorescence, and to characterise DOM through the wastewater treatment process.
The impact of fire on the geochemistry of speleothem-forming drip water in a sub-alpine cave
Publisher: Elsevier BV
Date: 11-2018
DOI: 10.1016/J.SCITOTENV.2018.05.310
Abstract: Fire dramatically modifies the surface environment by combusting vegetation and changing soil properties. Despite this well-documented impact on the surface environment, there has been limited research into the impact of fire events on karst, caves and speleothems. Here we report the first experiment designed to investigate the short-term impacts of a prescribed fire on speleothem-forming cave drip water geochemistry. Before and after the fire, water was collected on a bi-monthly basis from 18 drip sites in South Glory Cave, New South Wales, Australia. Two months post-fire, there was an increase in B, Si, Na, Fe and Pb concentrations at all drip sites. We conclude that this response is most likely due to the transport of soluble ash-derived elements from the surface to the cave drip water below. A significant deviation in stable water isotopic composition from the local meteoric water line was also observed at six of the sites. We hypothesise that this was due to partial evaporation of soil water resulting in isotopic enrichment of drip waters. Our results demonstrate that even low-severity prescribed fires can have an impact on speleothem-forming cave drip water geochemistry. These findings are significant because firstly, fires need to be considered when interpreting past climate from speleothem δ
Development and application of functional assays for freshwater dissolved organic matter
Publisher: Elsevier BV
Date: 11-2005
DOI: 10.1016/J.WATRES.2005.08.020
Abstract: A series of 11 standardised, reproducible, assays have been developed of physico-chemical functions of dissolved organic matter (DOM) in freshwaters. The assays provide quantitative information on light absorption, fluorescence, photochemical fading, pH buffering, copper binding, benzo(a)pyrene binding, hydrophilicity and adsorption to alumina. To obtain DOM for the assays, a 45 L s le of filtered freshwater was rotary-evaporated to reduce the volume to ca. 500 cm3. The concentrate was then passed through a strong cation exchanger, in the Na+ form, to remove alkaline-earth cations, and then through 0.7 and 0.2 microm filters. Eight s les, two each from a lake and three streamwaters, were processed. The yields of dissolved organic carbon (DOC) ranged from 70% to 107% (average 91%). The s les of DOM, stored in the dark at 4 degrees C, retained their functional assay characteristics for up to 7 months. When assaying the concentrates, parallel assays were performed with Suwannee River fulvic acid (SRFA), as a quality control standard. For most of the assays, the results for eight freshwater DOM s les are similar to those obtained with SRFA, the chief exception being the greater hydrophilicity of the DOM s les. For eight of the assays, variability among the DOM s les is significantly (p < 0.01) greater than can be explained by analytical error, i.e. by comparison with results for the SRFA quality standard the three exceptional assays are photochemical fading, copper binding and benzo(a)pyrene binding. The two lakewater s les studied gave the most extreme assay results, probably because of the influence of phytoplankton-derived DOM. Significant correlations of hydrophilicity and adsorption with optical absorbance may mean that some DOM functional properties can be predicted from comparatively simple measurements.
Characterisation of dissolved organic matter in the Lower Kinabatangan River, Sabah, Malaysia
Publisher: IWA Publishing
Date: 19-04-2014
DOI: 10.2166/NH.2014.196
Abstract: Spatial patterns and trends in the concentration and quality of dissolved organic matter (DOM) are characterised across a tropical agricultural catchment using ultraviolet (UV)-visible absorbance, and fluorescence spectroscopy. Related determination of the environmental isotopes 18O and 2H clarify the dynamics of catchment water movement. Water s les were collected from the Kinabatangan River, Borneo, and selected tributaries in August and September 2008 in four regions with oil palm plantations (KB1, KB2, KB3 and KB4). The isotopic compositions of surface waters suggest that canals were characterised by a strong evaporative effect than tributaries and streams with more natural, forested vegetation. DOM was characterised by variations in UV absorbance and spectral slope. In idual fluorescence excitation–emission matrices were decomposed by Parallel Factor Analysis (PARAFAC) and three components extracted (C1, C2 and C3). Components C2 and C3 both appear to be derived from microbial sources and/or photo-degradation. The PARAFAC components indicate a clear trend of increasing DOM degradation as waters pass through the catchment. It is hypothesised that upstream DOM is rapidly photo and microbially degraded to less fluorescent DOM, while DOM concentration and character of DOM downstream is controlled by the hydrology, specifically by variations in the rate of water movement.
Spectroscopic characterisation of dissolved organic matter changes in drinking water treatment: From PARAFAC analysis to online monitoring wavelengths
Publisher: Elsevier BV
Date: 05-2014
DOI: 10.1016/J.WATRES.2014.01.053
Abstract: Organic matter (OM) causes many problems in drinking water treatment. It is difficult to monitor OM concentrations and character during treatment processes due to its complexity. Fluorescence spectroscopy is a promising tool for online monitoring. In this study, a unique dataset of fluorescence excitation emission matrixes (EEMs) (n = 867) was collected from all treatment stages of five drinking water treatment plants (WTPs) situated in erse locations from subtropical to temperate climate. The WTPs incorporated various water sources, treatment processes and OM removal efficiencies (DOC removal 0%-68%). Despite these differences, four common fluorescence PARAFAC components were identified for characterisation of OM concentration and treatability. Moreover, fluorescence component ratios showed site-specific statistically significant correlations with OM removal, which contrasted with correlations between specific UV absorbance at 254 nm (SUVA) and OM removal that were not statistically significant. This indicates that use of fluorescence spectroscopy may be a more robust alternative for predicting DOC removal than UV spectroscopy. Based on the identified fluorescence components, four optical locations were selected in order to move towards single wavelength online OM monitoring.
Embracing the karst hydrological control on speleothem oxygen isotope variability
Publisher: Copernicus GmbH
Date: 15-05-2023
DOI: 10.5194/EGUSPHERE-EGU23-2947
Abstract: The influence of karst hydrology or & #8216 flowpaths& #8217 on speleothem oxygen isotopic (& #948 O) values has been simulated using karst forward models. & Cave monitoring studies have also shown that variability in dripwater & #948 O can be directly related to whether flowpaths are dominated by preferential/quick flow or diffuse/slow flow which challenges the paradigm of speleothems as archives of past variability in mean rainfall & #948 O.& Yet it is not known how common this flowpath effect is and whether it should be considered in the interpretation of speleothem & #948 O records. & Recently, Treble et al. (2022) analysed two global databases: SISAL v2 (Comas-Bru et al., 2020) and an extended compilation of dripwater from Baker et al. (2019).& It was demonstrated that within-cave variability in mean & #948 O values were common worldwide in both datasets. & An analysis of cave meta-data demonstrated that the flowpath effect is unrelated to climate, cave depth or lithology further supporting the ubiquitous nature of flowpaths, i.e., there is (1) a mixture of preferential and diffuse flow for all karstified carbonate rocks due to its triple-porosity nature (primary=matrix, secondary=fracture, tertiary=pipes and conduit) and (2) differences in soil/epikarst water storage and drainage characteristics.We demonstrate how a mechanistic understanding of flowpaths can lead to a more robust interpretation using a case study that is also relevant for managing water resources in the Mediterranean-type climate of south-west Australia.& Using seven modern stalagmite records from four caves, plus dripwater data, we demonstrate that the cave & #948 O record shows a common response to a sustained decrease in rainfall that impacted the region in the 1970s, characterised by a rise or & #8216 uptick& #8217 in & #948 O (Priestley et al., 2022).& Mean annual rainfall & #948 O values over the same period were quantified using observed and modelled data to have varied by & #8722 .4 to +0.1 & #8240 whereas the speleothem uptick is +1.5 & #8240 .& The much larger magnitude of the uptick is consistent with a reduction in the preferential-flow component to these caves driven by reduced rainfall recharge. & Preferential flow is an important contribution to groundwater. & The & #8216 uptick& #8217 or reduction in preferential flow implies that rainfall recharge to groundwater across the study region may no longer be reliably occurring.& The longer paleo-record for south-west Australia confirms that no replicated upticks are seen in the last 800 years in stalagmites from the region and highlights the impact of climate change to water security in a region heavily dependent on groundwater.& Comas-Bru, L. et al. SISALv2 (2020). A comprehensive speleothem isotope database with multiple age-depth models. Earth Syst. Sci. Data 12, 2579& #8211 (2020).Priestley, S., et al. (2022). Caves provide early warning of unprecedented decrease in rainfall recharge of groundwater. Research Square. doi:0.21203/rs.3.rs-1556439/v1Treble, P. C., et al. (2022). Ubiquitous karst hydrological control on speleothem oxygen isotope variability in a global study. Communications Earth & Environment, 3(1), 29. doi:10.1038/s43247-022-00347-3.
Intra-Event Trends in Stable Isotopes: Exploring Midlatitude Precipitation Using a Vertically Pointing Micro Rain Radar
Publisher: American Meteorological Society
Date: 02-2015
Abstract: Annual, monthly, and daily analyses of stable isotopes in precipitation are commonly made worldwide, yet only a few studies have explored the variations occurring on short time scales within in idual precipitation events, particularly at midlatitude locations. This study examines hydrogen isotope data from sequential, intra-event s les from 16 precipitation events during different seasons and a range of synoptic conditions over an 18-month period in Birmingham, United Kingdom. Precipitation events were observed simultaneously using a vertically pointing micro rain radar (MRR), which, for the first time at a midlatitude location, allowed high-resolution examination of the microphysical characteristics (e.g., rain rate, fall velocity, and drop size distributions) that may influence the local isotopic composition of rainwater. The range in the hydrogen isotope ratio (δD, where D refers to deuterium) in 242 s les during 16 events was from −87.0‰ to +9.2‰, while the largest variation observed in a single event was 55.4‰. In contrast to previous work, the results indicate that some midlatitude precipitation events do indeed show significant intra-event trends that are strongly influenced by precipitation processes and parameters such as rain rate, melting-level height, and droplet sizes. Inverse relationships between rain rate and isotopic composition are observed, representing an ex le of a local type of “amount effect,” a still poorly understood process occurring at different scales. For these particular events, the mean δ value may therefore not provide all the relevant information. This work has significance for the testing and development of isotope-enabled cloud-resolving models and land surface models at higher resolutions, and it provides improved insights into a range of environmental processes that are influenced by subs led precipitation events.
ENSO – cave dripwater hydrochemical relationship: a 7-year dataset from SE Australia
Publisher: Copernicus GmbH
Date: 02-06-2016
Abstract: Abstract. Speleothems (cave deposits), used for paleoenvironmental reconstructions, are deposited from cave dripwaters. Differentiating climate and karst processes within a dripwater signal is fundamental for the correct identification of paleoenvironmental proxies and ultimately their interpretation within speleothem records. We investigate the potential use of trace element and stable oxygen-isotope (δ18O) variations in cave dripwaters as paleorainfall proxies in an Australian alpine karst site. This paper presents the first extensive hydrochemical and δ18O dataset from Yarrangobilly Caves, in the Snowy Mountains, south-east Australia. Using a 7-year long rainfall δ18O and dripwater Ca, Cl, Mg / Ca, Sr / Ca and δ18O dataset from three drip sites, we determined that the processes of mixing, dilution, flow path change, carbonate mineral dissolution and Prior Calcite Precipitation (PCP) accounted for the observed variations in the dripwater geochemical composition. We identify that the three monitored drip sites are fed by fracture flow from a well-mixed epikarst storage reservoir supplied by variable concentrations of dissolved ions from soil and bedrock dissolution. We constrained the influence of multiple processes and controls on dripwater composition in a region dominated by ENSO. During the El Niño and dry periods, enhanced PCP, a flow path change and dissolution due to increased soil CO2 production occurred in response to decreased rainfall, in distinction to the La Niña phase where dilution dominated and reduced PCP was observed. We present a conceptual model, illustrating the key processes impacting the dripwater chemistry. We identified a robust relationship between ENSO and dripwater trace element concentrations and propose variations in speleothem Mg / Ca and Sr / Ca ratios may be interpreted to reflect paleorainfall conditions. These findings inform paleorainfall reconstruction from speleothems regionally and provide a basis for paleoclimate studies globally, in regions where there is intermittent recharge variability.
Molecular insights into the unique degradation trajectory of natural dissolved organic matter from surface to groundwater
Publisher: Copernicus GmbH
Date: 03-03-2021
DOI: 10.5194/EGUSPHERE-EGU21-1845
Abstract: & & Dissolved organic matter (DOM) comprises a large and complex range of molecules with varying mass, elemental arrangements, conformation, and polarity. These erse molecules interact with the environment resulting in changes to their molecular character and reactivity over time. Significant advances in our understanding of the molecular character of reactive and recalcitrant DOM have been made throughout the past decade, largely due to the development of ultra-high resolution techniques such as Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS). This understanding, however, is almost entirely based on surface water environments. Here, we investigate how the molecular properties of DOM change due to reactions occurring in a groundwater environment over time. We use FT-ICR MS combined with liquid chromatography organic carbon detection (LC-OCD), fluorescence and radiocarbon (& sup& & /sup& C) dissolved organic carbon (DOC) for a range of groundwater DOM s les, including the oldest DOC reported from a site which is not impacted by sedimentary organic carbon inputs (25,310 & #177 600 years BP). Our results indicate that polarity and nominal oxidation state of carbon (NOSC) play a major role in the reactivity of groundwater DOM, with a preferential removal of hydrophilic, high oxygen to carbon (O/C) ratio molecules over time (r& sub& s& /sub& = 0.91, p = 2.4 x 10& sup& -6& /sup& ). We also note an increase in likely bio-produced molecules containing low numbers of O atoms in deep methanogenic groundwater environments. These molecular formulae appear to accumulate due to the prolonged anoxic conditions which would not be experienced by surface water DOM. The decline in NOSC with increasing average bulk groundwater DOC age contrasts with findings from marine environments where NOSC has been reported to increase over time. Furthermore, the proportion of specific molecular formulae which are stable in marine waters, decline in groundwater as & sup& & /sup& C& sub& DOC& /sub& decreases (r& sub& s& /sub& = 0.68, p = 6.9 x 10& sup& -3& /sup& ) suggesting that current indicators of DOM degradation state derived from marine environments are not applicable to groundwater environments. Our research shows that the molecular character of reactive DOM in groundwater differs from that of surface water due to exposure to different environments and processing mechanisms, suggesting that it is the interaction between external environmental factors and intrinsic DOM molecular properties which control DOM recalcitrance.& &
The evolution of stable silicon isotopes in a coastal carbonate aquifer, Rottnest Island, Western Australia
Publisher: Copernicus GmbH
Date: 08-10-2020
Abstract: Abstract. Dissolved silicon (DSi) is a key nutrient in the oceans, but there are few data available regarding Si isotopes in coastal aquifers. Here we investigate the Si isotopic composition of 12 fresh and 17 saline groundwater s les from Rottnest Island, Western Australia, which forms part of the world’s most extensive aeolianite deposit (the Tamala Limestone Formation). Two bedrock s les were also collected from Rottnest Island for Si isotope analysis. The δ30Si values of groundwaters ranged from −0.39 to +3.60 ‰ with an (average: +1.59 ‰) and the rock s les were −0.76 and −0.13 ‰. Due to the relatively low concentrations of DSi (64 to 196 μM) and clay-forming cations in fresh groundwaters, the correlation between δ30Si values and DSi concentrations (ρ = 0.59, p = 0.02) may be explained by Si adsorption onto Fe-Al (oxy)hydroxides present in the aquifer. An increase in groundwater δ30Si in association with the occurrence of water-rock interactions may explain the spatial pattern in δ30Si across the aquifer, and is consistent with the correlation between δ30Si and tritium activities when considering all groundwaters (ρ = −0.68, p = 0.0002). In the deeper aquifer, the inverse correlation between DSi and Cl concentrations (ρ = −0.79, p = 0.04) for the more saline groundwaters is attributed to groundwater mixing with local seawater that is depleted in DSi (
SISAL speleothem database updates - link to modern monitoring data, additional proxies and increased accessibility
Publisher: Copernicus GmbH
Date: 27-03-2022
DOI: 10.5194/EGUSPHERE-EGU22-1576
Abstract: & & Speleothem archives (cave carbonates) are widely distributed in terrestrial regions, and provide highly resolved records of past changes in climate and vegetation encoded in the oxygen and carbon isotope proxies. The SISALv2 database, created by the PAGES-SISAL Phase 1 Working Group, provided 700 speleothem records from 293 cave sites, 500 of which have standardized chronologies. The database provides access to records that were hitherto unavailable in the original publications and/or repositories, and has enabled regional-to-global scale analysis of climatic patterns using a variety of approaches such as data-model comparisons.& & & & & The PAGES-SISAL Phase 2 Working Group is a continuation of the previous efforts to index speleothem datasets, focusing on the following objectives: (i) exploring ways to synthesise modern cave monitoring data to provide robust modern baselines and improve proxy interpretations, (ii) adding trace element proxies of Mg, Sr, Ba, U, and Sr isotopes to the SISAL database to increase our understanding of regional climatic variability, (iii) a database-update to incorporate ~100 identified speleothem datasets that are currently not in the database, (iv) providing a javascript web app with a user-friendly GUI to increase SISAL data accessibility.& & & & Here, we present preliminary information on available cave monitoring metadata synthesized from the Cave Monitoring Database (product of a Cave Monitoring workshop in Innsbruck, Austria) and published speleothem trace element records, highlighting regions where overlapping stable isotope, trace element and monitoring datasets are available, and identifying gaps. We show the proposed database structures for cave monitoring and speleothem trace element data, linking them to the speleothem entities in the existing SISAL database with persistent identifiers, and introduce the Beta version of the SISAL GUI. We briefly present a synopsis of the SISAL-community level discussions on best practices for reporting trace element data, and reducing data measured with high resolution laser ablation methods.& & & & & We welcome feedback on PAGES-SISAL Phase 2 activities listed above, and encourage participation and collaboration from interested researchers in different stages of their academic career and working in different geographical regions and allied disciplines.& &
Comparaison entre les lamines luminescentes et les lamines visibles annuelles de stalagmites
Publisher: Elsevier BV
Date: 08-1997
Drip water isotopes in semi-arid karst: Implications for speleothem paleoclimatology
Publisher: Elsevier BV
Date: 06-2014
The Properties of Annually Laminated Stalagmites-A Global Synthesis
Publisher: American Geophysical Union (AGU)
Date: 19-04-2021
DOI: 10.1029/2020RG000722
Abstract: Annually laminated speleothems have the potential to provide information on high‐frequency climate variability and, simultaneously, provide good chronological constraints. However, there are distinct types of speleothem annual laminae, from physical to chemical, and a common mechanism that links their formation has yet to be found. Here, we analyzed annually laminated stalagmites from 23 caves and 6 continents with the aim to find if there are common mechanisms underlying their development. Annually laminated stalagmites are least common in arid and semiarid climates, and most common in regions with a seasonality of precipitation. At a global scale, we observe faster growth rates with increasing mean annual temperature and decreasing latitude. Changepoints in average growth rates are infrequent and age‐depth relationships demonstrate that growth rates can be approximated to be constant. In general, annually laminated stalagmites are characterized by centennial‐scale stability in calcite precipitation due to a sufficiently large and well‐mixed water source, a time series spectrum showing first‐order autoregression due to mixing of stored water and annual recharged water, and an inter‐annual flickering of growth acceleration, bringing growth rates back to the long‐term mean. Climate forcing of growth rate variations is observed where a multi‐year climate signal is strong enough to be the dominant control on calcite growth rate variability, such that it retains a climate imprint after smoothing of this signal by mixing of stored water. In contrast, long‐term constant growth rate of laminated stalagmites adds further robustness to their unparalleled capacity to improve accuracy of chronology building.
Chaos and irregularity in karst percolation
Publisher: American Geophysical Union (AGU)
Date: 14-12-2012
DOI: 10.1029/2012GL054270
Freeze/thaw and pH effects on freshwater dissolved organic matter fluorescence and absorbance properties from a number of UK locations
Publisher: Elsevier BV
Date: 07-2007
DOI: 10.1016/J.WATRES.2007.04.012
Abstract: The UV-visible and fluorescence excitation-emission matrix spectrophotometric properties of dissolved organic matter (DOM) were compared for the effects of both pH and freeze/thaw on a wide range of freshwater DOM s les from the United Kingdom. It was observed that the spectrophotometric properties of our freshwater s les were sensitive to pH and that the recorded change varies with fluorescence and absorbance intensity, DOC concentration and the wavelength observed. Large and variable responses to pH were particularly severe at extremes of pH, but within the natural levels typically observed in freshwaters the response to pH was limited. For the same s le set large and variable responses were observed when subjected to freeze/thaw. From our data, knowledge of the original properties cannot be used to determine the amount of change that will occur with freezing and subsequent thawing. It is therefore recommended that in future research, to maintain the natural signal of the DOM, analysis is conducted at natural pH and without freezing to facilitate ease of comparison between studies. Our results also have implications for studies that utilise spectrophotometric techniques to investigate long-term trends in dissolved organic carbon in rivers. Spectrophotometric parameters from upland derived s les show varied responses of s les to pH and there is clear potential to complicate trends in the interpretation of long-term water colour data if pH is changing over time in a system or if s les are treated with different storage protocols with respect to acidification and freezing.
A soil moisture monitoring network to characterize karstic recharge and evapotranspiration at five representative sites across the globe
Publisher: Copernicus GmbH
Date: 08-2019
DOI: 10.5194/GI-2019-22
Abstract: Abstract. Karst systems that are characterized by a high subsurface heterogeneity are posing a challenge to study their complex recharge processes. Experimental methods to study karst processes mostly focus on characterizing the entire aquifer. Despite their important role for recharge processes, the limited focus has been given on studies of the soil and epikarst and most available research has been performed at sites of similar latitudes. In our study, we describe a new monitoring concept that allows the improvement of soil and epikarst processes understanding by covering different karst systems with different land cover at different climate regions. First, we describe the site selection and the experimental setup. Then we describe the five in idual sites and their soil profiles. We also present some preliminary data and highlight the potential of the data for future research aimed at answering the relevant research questions: (1) How do the soil and epikarst heterogeneities influence water flow and storage processes in the karst vadose zone? (2) What is the impact of the land cover type on karstic groundwater recharge and evapotranspiration? (3) What is the impact of climate on karstic groundwater recharge and evapotranspiration? In order to answer these questions, we monitor soil moisture, which controls the partitioning of rainfall into infiltration, soil water storage, evapotranspiration, and groundwater recharge processes. We installed a soil moisture-monitoring network at five different climate regions: in Puerto Rico (tropical), Spain (Mediterranean), the United Kingdom (humid oceanic), Germany (humid mountainous), and Australia (dry semi-arid). At each of the five sites, we defined two 20 m × 20 m plots to install soil moisture probes under different land use types (forest and grassland). At each plot, 15 soil moisture profiles were installed with probes at different depths from the top soil to the epikarst (over 400 soil moisture probes were installed). Our first results show that the monitoring network provides new insights into the soil moisture dynamics of the five study sites and that significant differences prevail among forest and grassland sites. Some profiles are characterized by sequential reactions of soil moisture, i.e., the uppermost probe reacts first and the lowest probe reacts last, while at other profiles, we find non-sequential reactions that we interpret to result from preferential flow processes. While the former favours storage in the soil providing water for evapotranspiration, the latter can be seen as an indicator for the initiation of fast and preferential recharge into the karst system. Covering the spatiotemporal variability of these processes through a large number of installed probes, our monitoring network will allow to develop a new conceptual understanding of evapotranspiration and groundwater recharge processes in karst regions across different climate regions and land use types, and provide the base for quantitative assessment with physically-based modelling approaches in the future.
Fluorescence intensity variations of speleothem‐forming groundwaters: Implications for paleoclimate reconstruction
Publisher: American Geophysical Union (AGU)
Date: 02-1999
DOI: 10.1029/1998WR900057
Fluorescence spectroscopy as a tool for determination of organic matter removal efficiency at water treatment works
Publisher: Copernicus GmbH
Date: 29-04-2010
Abstract: Abstract. Organic matter (OM) in drinking water treatment is a common impediment responsible for increased coagulant and disinfectant dosages, formation of carcinogenic disinfection-by products, and microbial re-growth in distribution system. The inherent heterogeneity of OM implies the utilization of advanced analytical techniques for its characterization and assessment of removal efficiency. Here, the application of simple fluorescence excitation-emission technique to OM characterization in drinking water treatment is presented. The fluorescence data of raw and clarified water was obtained from 16 drinking water treatment works. The reduction in fulvic-like fluorescence was found to significantly correlate with OM removal measured with total organic carbon (TOC). Fluorescence properties, fulvic- and tryptophan-like regions, were found to discriminate OM fractions of different removal efficiencies. The results obtained in the study show that fluorescence spectroscopy provides a rapid and accurate characterization and quantification of OM fractions and indication of their treatability in conventional water treatment.
Characterisation of colloidal and particulate organic carbon in freshwaters by thermal fluorescence quenching
Publisher: Elsevier BV
Date: 07-2007
DOI: 10.1016/J.WATRES.2007.04.017
Abstract: Three-dimensional excitation-emission matrix (EEM) fluorescence with thermal quenching has been applied to raw and size-fractionated freshwaters. To size-fractionate organic matter, sequential filtration through mixed-ester-cellulose membrane filters with nominal pore size of 1.2, 0.1 and 0.025 microm were used. Humic-like fluorophores (peaks A and C) have been found to dominate EEMs of raw and all size fractions of studied waters. Peak A fluorescence intensity has been found to be more thermally sensitive than peak C fluorescence intensity. Humic-like fluorescence intensity was generally size independent, which indicated that it was present mainly in the smallest size fraction (<0.025 microm). This was confirmed by total organic carbon (TOC) measurements. Peak T (tryptophan-like) fluorescence, that is widely associated with biological activity, exhibited a greater thermal sensitivity of fluorescence intensity in the larger size fractions, demonstrating the presence of more than one fluorophore in different size fractions at this location in optical space. Thermal fluorescence quenching provides insights into organic matter variability and associated colloidal characteristics.
Assessment of Low pH Coagulation Performance Using Fluorescence Spectroscopy
Publisher: American Society of Civil Engineers (ASCE)
Date: 07-2011
A 35 ka record of groundwater recharge in south-west Australia using stable water isotopes
Publisher: Elsevier BV
Date: 05-2020
DOI: 10.1016/J.SCITOTENV.2019.135105
Abstract: The isotopic composition of groundwater can be a useful indicator of recharge conditions and may be used as an archive to infer past climate variability. Groundwater from two largely confined aquifers in south-west Australia, recharged at the northernmost extent of the westerly wind belt, can help constrain the palaeoclimate record in this region. We demonstrate that radiocarbon age measurements of dissolved inorganic carbon are appropriate for dating groundwater from the Leederville aquifer and Yarragadee aquifer within the Perth Basin. Variations in groundwater δ
Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer
Publisher: Copernicus GmbH
Date: 30-04-2020
DOI: 10.5194/HESS-24-2167-2020
Abstract: Abstract. The terrestrial subsurface is the largest source of freshwater globally. The organic carbon contained within it and processes controlling its concentration remain largely unknown. The global median concentration of dissolved organic carbon (DOC) in groundwater is low compared to surface waters, suggesting significant processing in the subsurface. Yet the processes that remove this DOC in groundwater are not fully understood. The purpose of this study was to investigate the different sources and processes influencing DOC in a shallow anoxic coastal aquifer. Uniquely, this study combines liquid chromatography organic carbon detection with organic (δ13CDOC) carbon isotope geochemical analyses to fingerprint the various DOC sources that influence the concentration, carbon isotopic composition, and character with respect to distance from surface water sources, depth below surface, and inferred groundwater residence time (using 3H activities) in groundwater. It was found that the average groundwater DOC concentration was 5 times higher (5 mg L−1) than the global median concentration and that the concentration doubled with depth at our site, but the chromatographic character did not change significantly. The anoxic saturated conditions of the aquifer limited the rate of organic matter processing, leading to enhanced preservation and storage of the DOC sources from peats and palaeosols contained within the aquifer. All groundwater s les were more aromatic for their molecular weight in comparison to other lakes, rivers and surface marine s les studied. The destabilization or changes in hydrology, whether by anthropogenic or natural processes, could lead to the flux of up to 10 times more unreacted organic carbon from this coastal aquifer compared to deeper inland aquifers.
WlCount: Geological lamination detection and counting using an image analysis approach
Publisher: Elsevier BV
Date: 03-2022
Paleohydrological Records from Peat Profiles and Speleothems in Sutherland, Northwest Scotland
Publisher: Cambridge University Press (CUP)
Date: 03-2001
Abstract: Paleohydrological changes during the late Holocene are inferred from humification, testate amoebae, and pollen evidence from three blanket peat profiles in northwest Scotland. Replicate peat humification records from the Traligill basin share the same patterns of change for a 600-yr period of overlap between 1800 and 2400 cal yr B.P. The shared patterns, inferred from s les with a resolution of 5–13 yr, represent basinwide hydrological changes. In a nearby, but hydrologically separate, area with caves beneath peat, the luminescence emission wavelength measured in two speleothem s les correlated with the humification record in the overlying peat. This correlation implies that speleothem luminescence emission wavelength depends primarily on decay rates in the soils from which drip waters are derived, as long as there is no major change in soil or vegetation. The peat and speleothem records from the cave site further correlate with the peat records from the Traligill basin. Taken together, the records thus represent a regional climatic signal. Peaks in surface wetness replicated in two or more records occur at ca. 2300, 2090, 2030, 1820, 1600, and 1440 cal yr B.P. Further peaks occur at 800, 570, and 115 cal yr B.P. in the humification and stalagmite records that extend to the present day. Correlative changes have been observed, not only in other peat records from Scotland but also in ice accumulation at GISP2. These further correlations imply that precipitation regimes in Scotland and Greenland were in phase during the late Holocene.
Hydrological conceptual model for reconstructing fire history from cave stalagmites
Publisher: Copernicus GmbH
Date: 15-05-2023
DOI: 10.5194/EGUSPHERE-EGU23-2932
Abstract: Cave stalagmites (speleothems) are highly-valued archives of environmental information owing to their preservation of climate sensitive proxies and well-defined chronologies. & Yet the reconstruction of fire history from stalagmites is a relatively unexplored approach, with some advantages over traditional fire proxy archives.& For ex le, stalagmites may contain annual laminae (visible or chemical) which can be exploited for seasonal to annual proxy information with precise chronologies. & Thus stalagmites have the potential to yield annually-resolved records of fire and climate that could be used to (1) better understand the fire-climate relationship, (2) fire recurrence interval information, (3) understand ecosystem resilience and (4) inform land management policy.The development of fire proxies from stalagmites is still in its infancy. Robust interpretations of any proxy information relies on an understanding of the environmental processes that lead to the preservation of proxies in the archive. & Cave stalagmites may record fire history via dripwater, or via the cave entrance as aerosols. & The focus here is on the transportable constituents in dripwater such as solutes, colloids and suspended matter. & A fire event produces ash (a source of leachates) and can alter soil properties (hydrophobicity, pH, organic matter etc) producing temporary enrichments (or depletions) in transported constituents via dripwater.& The resulting signal may be detected in stalagmites using high-resolution methods such as laser ablation mass spectrometry, fluorescence and infrared microscopy techniques. & Cave depth is an important factor in the preservation process with the detection of a fire signal more likely to be observed in dripwater from shallow caves (e.g. 5-10 m) owing to the potential for attenuation and mixing that may occur in deeper caves (C bell et al., 2022).& However, owing to the karstification of carbonate rocks which host caves, there commonly exists different flow types: diffuse/slow flow through the matrix, preferential/fast flow through fractures and conduits.& Fracture (or conduit) influenced flowpaths have higher permeability and enhance rapid and deep percolation of water from the surface towards the cave.& Several studies have shown that stalagmites fed by dripwater with a fracture-flow component contain higher concentrations of soil-derived trace metals and organics indicating a stronger hydrological connection with the surface.& It logically follows that fracture-influenced flowpaths are more likely to transmit proxies for fire. & Furthermore, flowpaths may be a more important factor than cave depth in some settings, e.g., C bell et al. (2022) presented a case study of a historical fire event recorded in a stalagmite that was located ~40 m below the surface. & Understanding the hydrological setting of a cave system including rainfall recharge and flowpaths is valuable in the interpretation of speleothem records in general.& This contribution presents a conceptual model illustrating how these factors influence the preservation of fire proxies in stalagmites and makes recommendations for ideal s le selection for fire proxy records based on cave characteristics as well as stalagmite attributes such as morphology and colour.C bell. M. et al., Speleothems as Archives for Palaeofire Proxies.& ESS Open Archive.& July 24, 2022. DOI:10.1002/essoar.10511989.
Calculation of Past Dead Carbon Proportion and Variability by the Comparison of AMS 14C and Tims U/TH Ages on Two Holocene Stalagmites
Publisher: Cambridge University Press (CUP)
Date: 1999
DOI: 10.1017/S003382220005712X
Abstract: Twenty-two radiocarbon activity measurements were made by accelerator mass spectrometry (AMS) on 2 Holocene stalagmites from Belgium (Han-stm1b) and from southwest France (Vil-stm1b). Sixteen thermal ionization mass spectrometric (TIMS) U/Th measurements were performed parallel to AMS analyses. The past dead carbon proportion (dcp) due to limestone dissolution and old soil organic matter (SOM) degradation is calculated with U/Th ages, measured calcite 14 C activity and atmospheric 14 C activity from the dendrochronological calibration curves. Results show that the dcp is different for the 2 stalagmites: between 10,800 and 4780 yr from present dcp=17.5% (σ=2.4 n=10) for Han-stm1b and dcp=9.4% (σ=1.6 n=6) between 3070 and 520 yr for Vil-stm1b. Despite a broad stability of the dcp during the time ranges covered by each s le, a slight dcp increase of about 5.0% is observed in the Han-stm1b s le between 8500 and 5200 yr. This change is synchronous with a calcite δ 13 C increase, which could be due to variation in limestone dissolution processes possibly linked with a vegetation change. The dcp and δ 13 C of the 2 studied s les are compared with 5 other modern stalagmites from Europe. Results show that several factors intervene, among them: the vegetation type, and the soil saturation leading to variable dissolution process systems (open/closed). The good correlation (R 2 =0.98) between the U/Th ages and the calibrated 14 C ages corrected with a constant dcp validates the 14 C method. However, the dcp error leads to large 14 C age errors (i.e. 250–500 yr for the period studied), which is an obstacle for both a high-resolution chronology and the improvement of the 14 C calibration curves, at least for the Holocene.
Carbon dynamics in a Late Quaternary-age coastal limestone aquifer system undergoing saltwater intrusion
Publisher: Elsevier BV
Date: 12-2017
DOI: 10.1016/J.SCITOTENV.2017.06.094
Abstract: This study investigates the inorganic and organic aspects of the carbon cycle in groundwaters throughout the freshwater lens and transition zone of a carbonate island aquifer and identifies the transformation of carbon throughout the system. We determined
Characterisation of dissolved organic matter in karst spring waters using intrinsic fluorescence: Relationship with infiltration processes
Publisher: Elsevier BV
Date: 08-2011
DOI: 10.1016/J.SCITOTENV.2011.05.026
Abstract: From analysis of spectrophotometric properties of dissolved organic matter (OM) and the hydrochemical responses of some karst springs under different hydrologic conditions, an assessment of the origin and transfer pathway of OM present in karst spring waters, from soil and epikarst toward the spring, has been conducted for three karst aquifers in southern Spain: Alta Cadena, Sierra de Enmedio and Los Tajos. Intrinsic fluorescence (excitation-emission matrices or EEMs), together with major water chemistry (electrical conductivity, temperature, alkalinity, Cl⁻, Mg⁺²) and P(CO₂) along with natural hydrochemical tracers (TOC and NO₃⁻, have been monitored in 19 springs which drain the three karst aquifers examined in this study. The spring water EEM spectra indicate that fulvic acid-like substances, produced in the soil as a consequence of the decomposition of OM, are the dominant fluorophores, although some of the OM appears to originate from in situ microbiological activity but could be indicative of contamination present in recharge waters from livestock. During each recharge event, TOC and NO₃⁻ concentrations increased and variations in fluorescence intensities of peaks attributed to fulvic acid-like compounds were observed. In areas with minimal soil development, spatial and temporal variations in the fluorescence intensity of fulvic acid-like substances and other fluorophores derived from microbiological activity, together with other hydrochemical parameters, provide insights into the hydrogeological functioning of karst aquifers and the infiltration velocity of water from soil and facilitate assessment of contamination vulnerability in these aquifers.
Measuring dissolved organic carbon δ13C in freshwaters using total organic carbon cavity ring-down spectroscopy (TOC-CRDS)
Publisher: Springer Science and Business Media LLC
Date: 02-08-2012
Fluorescence wavelength and intensity variations of cave waters
Publisher: Elsevier BV
Date: 04-1999
Controls on cave drip water temperature and implications for speleothem-based paleoclimate reconstructions
Publisher: Elsevier BV
Date: 11-2015
Online fluorescence monitoring of RO fouling and integrity: Analysis of two contrasting recycled water schemes
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5EW00090D
Abstract: Underperformance in RO membranes were detected using fluorescence spectroscopy.
Water isotope systematics: Improving our palaeoclimate interpretations
Publisher: Elsevier BV
Date: 2016
Encyclopedia of caves D. C. Culver and W. B. White (eds) Publisher Elsevier Academic Press, 2004 (654 pp) ISBN 0 12 198651 9 (hardback)
Publisher: Wiley
Date: 2005
DOI: 10.1002/JQS.918
Reducing uncertainty in the climatic interpretations of speleothem δ18O
Publisher: American Geophysical Union (AGU)
Date: 21-05-2013
DOI: 10.1002/GRL.50467
The potential role of freshwater luminescence measurements in exploring runoff pathways in upland catchments
Publisher: Wiley
Date: 2001
DOI: 10.1002/HYP.223
Supplementary material to "Solar forced diurnal regulation of cave drip rates via phreatophyte evapotranspiration"
Publisher: Copernicus GmbH
Date: 15-02-2016
Dating stalagmites in mediterranean climates using annual trace element cycles
Publisher: Springer Science and Business Media LLC
Date: 04-04-2017
DOI: 10.1038/S41598-017-00474-4
Abstract: Speleothems may preserve geochemical information at annual resolution, preserving information about past hydrology, environment and climate. In this study, we advance information-extraction from speleothems in two ways. First, the limitations in dating modern stalagmites are overcome by refining a dating method that uses annual trace element cycles. It is shown that high-frequency variations in elements affected by prior calcite precipitation (PCP) can be used to date speleothems and yield an age within 2–4% chronological uncertainty of the actual age of the stalagmite. This is of particular relevance to mediterranean regions that display strong seasonal controls on PCP, due to seasonal variability in water availability and cave-air p CO 2 . Second, using the chronology for one stalagmite s le, trace elements and growth-rate are compared with a record of climate and local environmental change i.e. land-use and fire, over the 20 th century. Well-defined peaks in soil-derived trace elements and simultaneous decreases in growth-rate coincide with extreme annual rainfall totals in 1934 and 1974. One of which, 1934, was due to a recorded cyclone. We also find that bedrock-derived elements that are dominated by PCP processes, reflect a well-known period of drying in southwest Australia which began in the 1970’s.
The transfer of seasonal isotopic variability between precipitation and drip water at eight caves in the monsoon regions of China
Publisher: Elsevier BV
Date: 06-2016
Stalagmite luminescence and peat humification records of palaeomoisture for the last 2500 years
Publisher: Elsevier BV
Date: 1999
Comparison of river and canal water dissolved organic matter fluorescence within an urbanised catchment
Publisher: Wiley
Date: 30-09-2013
DOI: 10.1111/WEJ.12062
Impacts of cave air ventilation and in-cave prior calcite precipitation on Golgotha Cave dripwater chemistry, southwest Australia
Publisher: Elsevier BV
Date: 11-2015
Relating organic matter character to trihalomethanes formation potential: a data mining approach
Publisher: IWA Publishing
Date: 12-2008
DOI: 10.2166/WS.2008.150
Abstract: The removal of natural organic matter (NOM) during water treatment is becoming more important for all water utilities in the UK, as a result of tightened regulatory standards for trihalomethanes (THM), disinfection by-products (DBP) formed when residual organics react with chlorine. This paper considers the spatial and temporal variability of raw and clarified water arising from 16 surface water treatment works in the Midlands region of the UK. A wide range of investigation techniques are applied in order to develop effective strategies for the treatment of NOM-rich water. For the first time, rigorous data mining techniques are applied to a major dataset in order to examine potential inter-relationships between a wide range of quality parameters including, inter alia, total organic carbon (TOC), UV254, coagulation pH, resin fractionation (hydrophilic acids (HPIA), hydrophobic acids (HPOA), hydrophilic non-acids (HPINA)) and total THM formation potential (TTHMFP). This paper focuses on the use of principal component analysis (PCA) to develop robust algorithms for the prediction of TOC removal and hence THM formation. Results show that raw water characteristics can be categorised into three main types, according to their HPOA content and specific ultraviolet absorbance (SUVA.). PCA identified possible THMFP precursors, according to raw water type verified by strong statistical relationships.
Modification and preservation of environmental signals in speleothems
Publisher: Elsevier BV
Date: 03-2006
Environmental pressures on conserving cave speleothems: Effects of changing surface land use and increased cave tourism
Publisher: Elsevier BV
Date: 06-1998
An optimized chronology for a stalagmite using seasonal trace element cycles from Shihua Cave, Beijing, North China
Publisher: Springer Science and Business Media LLC
Date: 14-03-2018
DOI: 10.1038/S41598-018-22839-Z
Abstract: Stalagmites play an important role in paleoclimatic reconstructions from seasonal to orbital time scales as 230 Th-dating can provide an accurate absolute age. Additionally, seasonal trace element and optical layers can provide a precise age. We analyzed the seasonal variability of multiple trace elements on a stalagmite (XMG) in Shihua Cave, Beijing and compared them with results from laminae counting. The results show that (1) the polished section of the topmost part of XMG has obvious bi-optical layers under a conventional transmission microscope, however, laminae are not observed using this method in the rest of the s le, and (2) The variations of P/Ca, Sr/Ca, Ba/Ca, U/Ca and Mg/Ca show seasonal cycles throughout the s le. The PC1 in the Principal Component Analysis (PCA) of five trace elements represents the annual cycle. This stalagmite was deposited over 150 ± 1 years through PC1 peak counting. This result corresponds well with the annual layers and U-Th dating. Trace element cyclicity of PC1 can increase the accuracy of stalagmite dating, especially in the absence of obvious laminae and are a powerful method to identify seasonal changes in a strongly contrasting wet-dry monsoon climate region.
Oxygen isotope precipitation anomaly in the North Atlantic region during the 8.2 ka event
Publisher: Geological Society of America
Date: 12-2009
DOI: 10.1130/G30393A.1
SISALv2: A comprehensive speleothem isotope database with multiple age-depth models
Publisher: Copernicus GmbH
Date: 13-03-2020
DOI: 10.5194/ESSD-2020-39
Abstract: Abstract. Characterising the temporal uncertainty in palaeoclimate records is crucial for analysing past climate change, for correlating climate events between records, for assessing climate periodicities, identifying potential triggers, and to evaluate climate model simulations. The first global compilation of speleothem isotope records by the SISAL (Speleothem Isotope Synthesis and Analysis) Working Group showed that age-model uncertainties are not systematically reported in the published literature and these are only available for a limited number of records (ca. 15 %, n = 107/691). To improve the usefulness of the SISAL database, we have (i) improved the database’s spatio-temporal coverage and (ii) created new chronologies using seven different approaches for age-depth modelling. We have applied these alternative chronologies to the records from the first version of the SISAL database (SISALv1) and to new records compiled since the release of SISALv1. This paper documents the necessary changes in the structure of the SISAL database to accommodate the inclusion of the new age-models and their uncertainties as well as the expansion of the database to include new records and the quality-control measures applied. This paper also documents the age-depth model approaches used to calculate the new chronologies. The updated version of the SISAL database (SISALv2) contains isotopic data from 691 speleothem records from 294 cave sites and new age-depth models, including age-depth temporal uncertainties for 512 speleothems. SISALv2 is available at 0.17864/1947.242 (Comas-Bru et al., 2020).
Discriminatory classification of natural and anthropogenic waters in two U.K. estuaries
Publisher: Elsevier BV
Date: 02-2007
DOI: 10.1016/J.SCITOTENV.2006.10.052
Abstract: The ability to distinguish water inputs from both natural and anthropogenic sources was investigated in the complex environment of an urban estuary (Tyne) and a relatively pristine estuary (Tweed). We used a data set from a total of 11 estuarine transects, comprising measurements of bulk dissolved organic matter (dissolved organic carbon and nitrogen), dissolved nitrogen (total dissolved nitrogen, ammonium, nitrate+nitrite and dissolved organic nitrogen), optical absorbance measurements (a350, S290-350) and fluorescence excitation emission matrix measurements (fluorophores A, H, B and T intensity and A and H emission wavelength maxima). In order to investigate trends within the numerous parameters measured, multivariate statistics were employed. Principal components analyses showed 63.4% of the variability in the total data set can be explained by two sets of components and 74.9% of the variability by the spectrophotometric measurements alone. In both analyses the first component correlated to the mixing of terrestrial and marine waters and the second component was correlated to sources of pollution such as domestic sewage. Within the data set, river flow and terrestrially derived DOM were significantly correlated, and situations with high river input showed an increase in terrestrial signature in the estuary. Discriminant analyses were also carried out and indicated that 59.8% (total data set) and 53.3% (solely spectrophotometric data) of the s les can be correctly classified into their respective groups (water categories) assigned on the basis of salinity and s ling location. Overall the results clearly show the potential of spectrophotometric techniques to discriminate distinct water categories with different DOM characteristics. In particular, measurement of the fluorophore H emission maxima, the spectral slope parameter, S290-350, and fluorophores T and B intensity enabled discrimination of DOM from riverine, estuarine, marine, and sewage affected water categories. The results presented here indicate the ability of spectrophotometric data alone to distinguish between marine, anthropogenic and terrestrial DOM and distinguish terrestrial DOM from different catchments (Tyne vs. Tweed). With current advances in the in-situ deployment of absorbance and fluorescence spectroscopy it is anticipated that multivariate statistics will gain importance as a cost effective, powerful and diagnostic approach to assessing the distributions of water types and their associated DOM characteristics and fluxes at the land-ocean interface.
Fluorescence as a potential monitoring tool for recycled water systems: A review
Publisher: Elsevier BV
Date: 03-2009
DOI: 10.1016/J.WATRES.2008.11.027
Abstract: A rapid, highly sensitive and selective detector is urgently required to detect contamination events in recycled water systems - for ex le, cross-connection events in dual reticulation pipes that recycle advanced treated sewage effluent - as existing technologies, including total organic carbon and conductivity monitoring, cannot always provide the sensitivity required. Fluorescence spectroscopy has been suggested as a potential monitoring tool given its high sensitivity and selectivity. A review of recent literature demonstrates that by monitoring the fluorescence of dissolved organic matter (DOM), the ratios of humic-like (Peak C) and protein-like (Peak T) fluorescence peaks can be used to identify trace sewage contamination in river waters and estuaries, a situation analogous to contamination detection in recycled water systems. Additionally, strong correlations have been shown between Peak T and biochemical oxygen demand (BOD) in rivers, which is indicative of water impacted by microbial activity and therefore of sewage impacted systems. Hence, this review concludes that the sensitive detection of contamination events in recycled water systems may be achieved by monitoring Peak T and/or Peak C fluorescence. However, in such systems, effluent is treated to a high standard resulting in much lower DOM concentrations and the impact of these advanced treatment processes on Peaks T and C fluorescence is largely unknown and requires investigation. This review has highlighted that further work is also required to determine (a) the stability and distinctiveness of recycled water fluorescence in relation to the treatment processes utilised, (b) the impact of matrix effects, particularly the impact of oxidation, (c) calibration issues for online monitoring, and (d) the advanced data analytical techniques required, if any, to improve detection of contamination events.
Functional properties of DOM in a stream draining blanket peat
Publisher: Elsevier BV
Date: 15-12-2008
DOI: 10.1016/J.SCITOTENV.2008.09.011
Abstract: The functional properties of dissolved organic matter (DOM) from Rough Sike, a stream draining blanket peat in the northern Pennines, UK, were investigated using a series of 12 standardised assays. Nine stream s les were collected at different discharges during 2003--2006, and DOM concentrates obtained by low temperature rotary evaporation. Suwannee River Fulvic Acid was used as a quality control standard in the assays. Dissolved organic matter in high-discharge s les was more light-absorbing at 280 and 340 nm and adsorbed more strongly to alumina, than DOM characteristic of low streamflow, but was less fluorescent and hydrophilic, and poorer in proton-dissociating groups. No significant differences were found in light absorption at 254 nm, copper- or benzo(a)pyrene binding, or photochemical fading. Combination of the Rough Sike data with previously-published results for other streams and a lake yields totals of 20-23 values per assay, for a range of DOM types. For the combined data, variability in all the assays is significant (p < 0.001), as judged by comparison with variations in repeat measurements on the quality control standard. Analysis of the combined data shows that DOM hydrophilicity and adsorption are well-predicted by linear relationships with the extinction coefficient at 340 nm (E340), while good quadratic relationships exist between E340 and both buffering capacity and fluorescence.
Fluorescence of leachates from three contrasting landfills
Publisher: Elsevier BV
Date: 05-2004
Temporal controls on dissolved organic matter and lignin biogeochemistry in a pristine tropical river, Democratic Republic of Congo
Publisher: American Geophysical Union (AGU)
Date: 06-08-2010
DOI: 10.1029/2009JG001180
Chemical characterisation and source identification of atmospheric aerosols in the Snowy Mountains, south-eastern Australia
Publisher: Elsevier BV
Date: 07-2018
DOI: 10.1016/J.SCITOTENV.2018.02.231
Abstract: Characterisation of atmospheric aerosols is of major importance for: climate, the hydrological cycle, human health and policymaking, biogeochemical and palaeo-climatological studies. In this study, the chemical composition and source apportionment of PM
SISALv3: A global speleothem stable isotope and trace element database
Publisher: Copernicus GmbH
Date: 13-09-2023
Forward modelling of the speleothem oxygen isotope paleoclimate proxy
Publisher: Elsevier BV
Date: 11-2012
Biogeochemical cycling of sulphur in karst and transfer into speleothem archives at Grotta di Ernesto, Italy
Publisher: Springer Science and Business Media LLC
Date: 22-11-2012
Functional variability of dissolved organic matter from the surface water of a productive lake
Publisher: Elsevier BV
Date: 2008
DOI: 10.1016/J.WATRES.2007.07.006
Abstract: Functional variability of dissolved organic matter (DOM) from the surface water of Esthwaite Water (N. England) was investigated using a series of 12 standardised assays, which provide quantitative information on light absorption, fluorescence, photochemical fading, pH buffering, copper binding, benzo(a)pyrene binding, hydrophilicity, and adsorption to alumina. Ten lakewater s les were collected at different times of year during 2003-2005, and DOM concentrates obtained by low-temperature rotary evaporation. Suwannee River Fulvic Acid was used as a quality control standard. For nine of the assays, variability among DOM s les was significantly (p<0.01) greater than could be explained by analytical error. Seasonal trends observed for six of the assays could be explained by a simple mixing model in which the two end-members were DOM from the catchment (allochthonous) and DOM produced within the lake (autochthonous). The fraction of autochthonous DOM predicted by the model is significantly correlated (p<0.01) with chlorophyll concentration, consistent with production from phytoplankton. Autochthonous DOM is less light-absorbing, less fluorescent, more hydrophilic, and possesses fewer proton-dissociating groups, than allochthonous material.
Characterisation of the fluorescence from freshwater, planktonic bacteria
Publisher: Elsevier BV
Date: 06-2006
DOI: 10.1016/J.WATRES.2006.03.017
Abstract: Amino acid-like fluorescence has been used as an indicator of biological activity in wastewater effluent and in natural waters, and can be detected using fluorescence spectroscopy. Little or no work has been able to state conclusively that these so called 'amino acid-like' fluorophores are associated with proteins present as a result of bacterial activity. This work aims to ascertain whether bacteria are one possible cause of these 'amino acid-like' peaks observed in natural waters. In addition, fluorescence derived solely from one bacterial source was determined as a function of the growth time and temperature. The bacterium Pseudomonas aeruginosa was isolated from the urban River Tame, Birmingham, UK, and planktonic bacteria were grown in sterile, sealed glass jars, in 100 ml growth media. Bacteria were grown at 11, 25 and 37 degrees C, over a maximum of 10 days. A 3D Excitation-Emission Matrix (EEM) plot was generated from fluorescence analysis of the s les. Both tryptophan and tyrosine-like fluorescence, resembling that observed in natural and waste waters, was observed in these s les, indicating that observed fluorescence signals from aquatic systems in the literature were of biotic origin. Significant differences in fluorescence signals were obtained from planktonic cells grown at different temperatures. At 25 and 37 degrees C, cells were found to produce predominantly tryptophan-like fluorescence, with some tyrosine-like fluorescence also detected. A further unknown fluorophore was also detected (emission wavelength of approximately 460 nm, with three excitation centres at 225, 260 and 390 nm), likely to be a bacterially produced metabolite. At 11 degrees C, a more environmentally realistic temperature in temperate environments, quantitative and qualitative differences were observed in fluorescence signals when compared with the higher temperatures, indicating that laboratory observations conducted at higher temperatures may not be easily used to interpret environmental processes.
A reassessment of the Lower Namoi Catchment aquifer architecture and hydraulic connectivity with reference to climate drivers
Publisher: Informa UK Limited
Date: 03-04-2014
Lithium and strontium isotope dynamics in a carbonate island aquifer, Rottnest Island, Western Australia
Publisher: Elsevier BV
Date: 05-2020
Modern stalagmite δ18O: Instrumental calibration and forward modelling
Publisher: Elsevier BV
Date: 04-2010
Solar-forced diurnal regulation of cave drip rates via phreatophyte evapotranspiration
Publisher: Copernicus GmbH
Date: 03-11-2016
DOI: 10.5194/HESS-20-4439-2016
Abstract: Abstract. We present results of a detailed study of drip rate variations at 12 drip discharge sites in Glory Hole Cave, New South Wales, Australia. Our novel time series analysis, using the wavelet synchrosqueezed transform, reveals pronounced oscillations at daily and sub-daily frequencies occurring in 8 out of the 12 monitored sites. These oscillations were not spatially or temporally homogenous, with different drip sites exhibiting such behaviour at different times of year in different parts of the cave. We test several hypotheses for the cause of the oscillations, including variations in pressure gradients between karst and cave due to cave breathing effects or atmospheric and earth tides, variations in hydraulic conductivity due to changes in viscosity of water with daily temperature oscillations, and solar-driven daily cycles of vegetative (phreatophytic) transpiration. We conclude that the only hypothesis consistent with the data and hydrologic theory is that daily oscillations are caused by solar-driven pumping by phreatophytic trees which are abundant at the site. The daily oscillations are not continuous and occur sporadically in short bursts (2–14 days) throughout the year due to non-linear modification of the solar signal via complex karst architecture. This is the first indirect observation leading to the hypothesis of tree water use in cave drip water. It has important implications for karst hydrology in regards to developing a new protocol to determine the relative importance of trends in drip rate, such as diurnal oscillations, and how these trends change over timescales of weeks to years. This information can also be used to infer karst architecture. This study demonstrates the importance of vegetation on recharge dynamics, information that will inform both process-based karst models and empirical estimation approaches. Our findings support a growing body of research exploring the impact of trees on speleothem paleoclimate proxies.
In situ fluorescence measurements of dissolved organic matter: A review
Publisher: Elsevier BV
Date: 2020
DOI: 10.1016/J.SCITOTENV.2019.134361
Abstract: There is a need for an inexpensive, reliable and fast monitoring tool to detect contaminants in a short time, for quick mitigation of pollution sources and site remediation, and for characterization of natural dissolved organic matter (DOM). Fluorescence spectroscopy has proven to be an excellent technique in quantifying aquatic DOM, from autochthonous, allochthonous or anthropogenic sources. This paper reviews the advances in in situ fluorescence measurements of DOM and pollutants in various water environments. Studies have demonstrated, using high temporal-frequency DOM fluorescence data, that marine autochthonous production of DOM is highly complex and that the allochthonous input of DOM from freshwater to marine water can be predicted. Furthermore, river measurement studies found a delayed fluorescence response of DOM following precipitation compared to turbidity and discharge, with various lags, depending on season, site and input of dissolved organic carbon (DOC) concentration. In addition, research has shown that blue light fluorescence (λ
The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems
Publisher: Copernicus GmbH
Date: 16-04-2018
DOI: 10.5194/ESSD-2018-17
Abstract: Abstract. Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-s le” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for in idual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (δ18O, δ13C) measurements are referenced by distance from the top or youngest part of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information about the full range of measurements carried out on each speleothem and information about the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data. The compiled data are available at 0.17864/1947.139.
ENSO–cave drip water hydrochemical relationship: A 7-year dataset from south-eastern Australia
Publisher: Copernicus GmbH
Date: 17-11-2016
DOI: 10.5194/HESS-20-4625-2016
Abstract: Abstract. Speleothems (cave deposits), used for palaeoenvironmental reconstructions, are deposited from cave drip water. Differentiating climate and karst processes within a drip-water signal is fundamental for the correct identification of palaeoenvironmental proxies and ultimately their interpretation within speleothem records. We investigate the potential use of trace element and stable oxygen-isotope (δ18O) variations in cave drip water as palaeorainfall proxies in an Australian alpine karst site. This paper presents the first extensive hydrochemical and δ18O dataset from Harrie Wood Cave, in the Snowy Mountains, south-eastern (SE) Australia. Using a 7-year long rainfall δ18O and drip-water Ca, Cl, Mg / Ca, Sr / Ca and δ18O datasets from three drip sites, we determined that the processes of mixing, dilution, flow path change, carbonate mineral dissolution and prior calcite precipitation (PCP) accounted for the observed variations in the drip-water geochemical composition. We identify that the three monitored drip sites are fed by fracture flow from a well-mixed epikarst storage reservoir, supplied by variable concentrations of dissolved ions from soil and bedrock dissolution. We constrained the influence of multiple processes and controls on drip-water composition in a region dominated by El Niño–Southern Oscillation (ENSO). During the El Niño and dry periods, enhanced PCP, a flow path change and dissolution due to increased soil CO2 production occurred in response to warmer than average temperatures in contrast to the La Niña phase, where dilution dominated and reduced PCP were observed. We present a conceptual model, illustrating the key processes impacting the drip-water chemistry. We identified a robust relationship between ENSO and drip-water trace element concentrations and propose that variations in speleothem Mg / Ca and Sr / Ca ratios may be interpreted to reflect palaeorainfall conditions. These findings inform palaeorainfall reconstruction from speleothems regionally and provide a basis for palaeoclimate studies globally, in regions where there is intermittent recharge variability.
From soil to cave: Transport of trace metals by natural organic matter in karst dripwaters
Publisher: Elsevier BV
Date: 04-2012
River–groundwater connectivity in a karst system, Wellington, New South Wales, Australia,Connectivité entre rivière et eaux souterraines d’un système karstique, Wellington, New South Wales, Australie,Conectividade rio–água subterrânea em um sistema cárstico, Wellington, Nova Gales do Sul, Austrália,Conectividad agua subterránea–río en un sistema kárstico, Wellington, New South Wales, Australia
Publisher: Springer Science and Business Media LLC
Date: 07-12-2017
Fluorescence spectroscopy for wastewater monitoring: A review
Publisher: Elsevier BV
Date: 05-2016
DOI: 10.1016/J.WATRES.2016.03.021
Abstract: Wastewater quality is usually assessed using physical, chemical and microbiological tests, which are not suitable for online monitoring, provide unreliable results, or use hazardous chemicals. Hence, there is an urgent need to find a rapid and effective method for the evaluation of water quality in natural and engineered systems and for providing an early warning of pollution events. Fluorescence spectroscopy has been shown to be a valuable technique to characterize and monitor wastewater in surface waters for tracking sources of pollution, and in treatment works for process control and optimization. This paper reviews the current progress in applying fluorescence to assess wastewater quality. Studies have shown that, in general, wastewater presents higher fluorescence intensity compared to natural waters for the components associated with peak T (living and dead cellular material and their exudates) and peak C (microbially reprocessed organic matter). Furthermore, peak T fluorescence is significantly reduced after the biological treatment process and peak C is almost completely removed after the chlorination and reverse osmosis stages. Thus, simple fluorometers with appropriate wavelength selectivity, particularly for peaks T and C could be used for online monitoring in wastewater treatment works. This review also shows that care should be taken in any attempt to identify wastewater pollution sources due to potential overlapping fluorophores. Correlations between fluorescence intensity and water quality parameters such as biochemical oxygen demand (BOD) and total organic carbon (TOC) have been developed and dilution of s les, typically up to ×10, has been shown to be useful to limit inner filter effect. It has been concluded that the following research gaps need to be filled: lack of studies on the on-line application of fluorescence spectroscopy in wastewater treatment works and lack of data processing tools suitable for rapid correction and extraction of data contained in fluorescence excitation-emission matrices (EEMs) for real-time studies.
To what extent can portable fluorescence spectroscopy be used in the real-time assessment of microbial water quality?
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.SCITOTENV.2015.05.114
Abstract: The intrinsic fluorescence of aquatic organic matter emitted at 350 nm when excited at 280 nm correlates widely with water quality parameters such as biochemical oxygen demand. Hence, in sewage-impacted rivers and groundwater, it might be expected that fluorescence at these wavelengths will also correlate with the microbial water quality. In this paper we use a portable fluorimeter to assess the relationship between fluorescence intensity at this wavelength pair and Escherichia coli enumeration in contrasting river catchments of poor water quality: in KwaZulu-Natal, S. Africa and the West Midlands, UK. Across all catchments we demonstrate a log correlation (r = 0.74) between fluorescence intensity and E. coli over a seven-log range in E. coli enumerations on non-perturbed (unfiltered) s les. Within specific catchments, the relationship between fluorescence intensity and E. coli is more variable, demonstrating the importance of catchment-specific interference. Our research demonstrates the potential of using a portable fluorimeter as an initial screening tool for indicative microbial water quality, and one that is ideally suited to simple pollution scenarios such as assessing the impact of faecal contamination in river or groundwater at specific sites.
Comparison of the luminescence properties of waters depositing flowstone and stalagmites at Lower Cave, Bristol
Publisher: Wiley
Date: 07-1998
DOI: 10.1002/(SICI)1099-1085(199807)12:9<1447::AID-HYP649>3.0.CO;2-1
Supplementary material to "A post-wildfire response in cave dripwater chemistry"
Publisher: Copernicus GmbH
Date: 19-01-2016
Reconstructing Climate Dynamics Over the Past Millennium: Synoptic‐Scale Climate Dynamics Over the Last Millennium: A Case Study for the MCA‐LIA Transition; Kippel, Switzerland, 17–20 May 2009
Publisher: American Geophysical Union (AGU)
Date: 18-08-2009
DOI: 10.1029/2009EO330004
Cross-connection detection in Australian dual reticulation systems by monitoring inherent fluorescent organic matter
Publisher: Informa UK Limited
Date: 11-2012
Supplementary material to "SISALv2: A comprehensive speleothem isotope database with multiple age-depth models"
Publisher: Copernicus GmbH
Date: 13-03-2020
Fractionation of Freshwater Colloids and Particles by SPLITT: Analysis by Electron Microscopy and 3D Excitation−Emission Matrix Fluorescence
Publisher: American Chemical Society (ACS)
Date: 27-04-2006
DOI: 10.1021/AC0521347
Abstract: This paper reports the first application of a combined approach utilizing split-flow thin-cell (SPLITT) separation to size fractionate natural aquatic colloids and particles collected from freshwater s les. No s le preconcentration was performed although some s les were investigated after alteration of the ambient pH. The unfractionated and fractionated s les were analyzed by scanning electron microscopy (SEM), environmental SEM, and 3D excitation emission matrix fluorescence. Qualitative and quantitative results by microscopy indicated that SPLITT produces well-resolved fractionations at appropriate sizes but with some perturbation of the s le. In addition, tryptophan-like fluorescence was shown to be caused by different organic moieties compared with humic-like and fulvic-like fluorescence. Tryptophan-like fluorescence intensity is found mainly in the particulate material but is not pH dependent, while humic- and fulvic-like fluorescence intensities are dependent on pH but not on size. Fulvic-like fluorescence intensity normalized to absorbance, related to fluorescence efficiency and molar mass, varies with size.
An isotopic and modelling study of flow paths and storage in Quaternary calcarenite, SW Australia: Implications for speleothem paleoclimate records
Publisher: Elsevier BV
Date: 03-2013
Marine biomarkers from ice cores reveal enhanced high-latitude Southern Ocean carbon sink during the Antarctic Cold Reversal
Publisher: California Digital Library (CDL)
Date: 24-05-2019
Spectrophotometric properties of surface water dissolved organic matter in an afforested upland peat catchment
Publisher: Wiley
Date: 08-10-2008
DOI: 10.1002/HYP.6827
Classification and calibration of organic matter fluorescence data with multiway analysis methods and artificial neural networks: an operational tool for improved drinking water treatment
Publisher: Wiley
Date: 16-07-2010
DOI: 10.1002/ENV.1045
Hydroclimate of the Last Glacial Maximum and deglaciation in southern Australia’s arid margin interpreted from speleothem records (23–15 ka)
Publisher: Copernicus GmbH
Date: 21-12-2016
DOI: 10.5194/CP-2016-135
Abstract: Abstract. Terrestrial data spanning the Last Glacial Maximum (LGM) and deglaciation from the southern Australian region are sparse, and limited to discontinuous sedimentological and geomorphological records with relatively large chronological uncertainties. This dearth of records has prevented a critical assessment of the role of the Southern Hemisphere mid-latitude westerly winds on the region’s climate during this time period. In this study, two precisely-dated speleothem records for Mairs Cave, Flinders Ranges, are presented, providing a detailed terrestrial hydroclimatic record for the southern Australian drylands during 23–15 ka for the first time. Enhanced recharge to Mairs Cave is interpreted from the speleothem record by the activation of growth, physical flood layering and δ18O and δ13C minima. Periods of lowered recharge are indicated by isotopic enrichment, primarily affecting δ18O, argued to be driven by evaporation of shallow soil/epikarst water in this water-limited environment. A hydrological driver is supported by calcite fabric changes. The Mairs Cave record indicates that the Flinders Ranges were relatively wet during the LGM and early deglaciation, particularly over the interval 18.9–16 ka. This wetter phase ended abruptly with a shift to drier conditions at 15.8 ka. These findings are in agreement with the geomorphic archives for this region, as well as the timing of events in records from the broader Australasian region. The recharge phases identified in the Mairs Cave record are correlated with, but antiphase to, the position of the westerly winds interpreted from a marine core in the Great Australian Bight. The implication is that the mid-latitude westerlies are located further south during the period of enhanced recharge in the Mairs Cave record (18.9–16 ka), and conversely are located further north when greater aridity is interpreted in the speleothem record. A comparison with speleothem records from the northern Australasian region reveals that the availability of sub-tropical/tropical moisture is the most likely explanation driving enhanced recharge, with further lification of recharge occurring during the early half of Heinrich Stadial 1, possibly influenced by a more southerly-displaced Intertropical Convergence Zone (ITCZ). A rapid transition to aridity at 15.8 ka is consistent with a retraction of this tropical moisture source.
Supplementary material to "ENSO – cave dripwater hydrochemical relationship: a 7-year dataset from SE Australia"
Publisher: Copernicus GmbH
Date: 02-06-2016
Global analysis reveals climatic controls on the oxygen isotope composition of cave drip water
Publisher: Springer Science and Business Media LLC
Date: 05-07-2019
DOI: 10.1038/S41467-019-11027-W
Abstract: The oxygen isotope composition of speleothems is a widely used proxy for past climate change. Robust use of this proxy depends on understanding the relationship between precipitation and cave drip water δ 18 O. Here, we present the first global analysis, based on data from 163 drip sites, from 39 caves on five continents, showing that drip water δ 18 O is most similar to the amount-weighted precipitation δ 18 O where mean annual temperature (MAT) is 10 °C. By contrast, for seasonal climates with MAT 10 °C and 16 °C, drip water δ 18 O records the recharge-weighted δ 18 O. This implies that the δ 18 O of speleothems (formed in near isotopic equilibrium) are most likely to directly reflect meteoric precipitation in cool climates only. In warmer and drier environments, speleothems will have a seasonal bias toward the precipitation δ 18 O of recharge periods and, in some cases, the extent of evaporative fractionation of stored karst water.
A late Middle Pleistocene temperate–periglacial–temperate sequence (Oxygen Isotope Stages 7–5e) near Marsworth, Buckinghamshire, UK
Publisher: Elsevier BV
Date: 12-2001
Hydrological modeling of stalagmite δ18O response to glacial‐interglacial transitions
Publisher: American Geophysical Union (AGU)
Date: 19-06-2013
DOI: 10.1002/GRL.50555
A 9000-year carbon isotopic record of acid-soluble organic matter in a stalagmite from Heshang Cave, central China: Paleoclimate implications
Publisher: Elsevier BV
Date: 11-2014
New data mining and calibration approaches to the assessment of water treatment efficiency
Publisher: Elsevier BV
Date: 02-2012
Hyperspectral imaging of speleothems
Publisher: Elsevier BV
Date: 08-2008
The evolution of stable silicon isotopes in a coastal carbonate aquifer on Rottnest Island, Western Australia
Publisher: Copernicus GmbH
Date: 02-07-2021
DOI: 10.5194/HESS-25-3837-2021
Abstract: Abstract. Dissolved silicon (dSi) is a key nutrient in the oceans, but data regarding Si isotopes in coastal aquifers are not widely available. Here we investigate the Si isotopic composition of 12 fresh and 16 saline groundwater s les from Rottnest Island, Western Australia, which forms part of the world's most extensive aeolianite deposit (the Tamala Limestone formation). In total, two bedrock s les were also collected from Rottnest Island for Si isotope analysis. The δ30Si values of groundwater s les ranged from −0.4 ‰ to +3.6 ‰ with an average +1.6 ‰, and the rock s les were −0.8 ‰ and −0.1 ‰. The increase in δ30Si values in fresh groundwater is attributed to the removal of the lighter Si isotopes into secondary minerals and potentially also adsorption onto Fe (oxy)hydroxides. The positive correlations between δ30Si values and dSi concentrations (ρ = 0.59 p = 0.02) and δ30Si values and Cl, but not dSi and Cl concentrations, are consistent with vertical mixing between the younger fresh groundwater and the deeper groundwater, which have undergone a greater degree of water–rock interactions. This has produced a spatial pattern in δ30Si across the aquifer due to the local hydrogeology, resulting in a correlation between δ30Si and tritium activities when considering all groundwater types (ρ = −0.68 p = 0.0002). In the deeper aquifer, the inverse correlation between dSi and Cl concentrations (ρ = −0.79 p = 0.04) for the more saline groundwater is attributed to groundwater mixing with local seawater that is depleted in dSi ( 3.6 µM). Our results from this well-constrained island aquifer system demonstrate that stable Si isotopes usefully reflect the degree of water–aquifer interactions, which is related to groundwater residence time and local hydrogeology. Our finding that lithogenic Si dissolution occurs in the freshwater lens and the freshwater–seawater transition zone on Rottnest Island appears to supports the recent inclusion of a marine–submarine groundwater discharge term in the global dSi mass balance. Geologically young carbonate aquifers, such as Rottnest Island, may be an important source of dSi in coastal regions with low riverine input and low oceanic dSi concentrations.
Investigation into clouds and precipitation over an urban area using micro rain radars, satellite remote sensing and fluorescence spectrophotometry
Publisher: Elsevier BV
Date: 05-2010
Speleothems as archives for palaeofire proxies
Publisher: Copernicus GmbH
Date: 15-05-2023
DOI: 10.5194/EGUSPHERE-EGU23-11016
Abstract: Environmental proxy archives such as tree rings, sediment cores, and ice cores are commonly used to investigate past fire regimes. Speleothems, naturally forming cave decorations mainly comprising of stalagmites, stalactites, and flowstones, have been extensively used as palaeoenvironmental archives as their physical attributes and chemical composition change with changed environment. Research has shown that cave drip water chemistry responds to fire events, and more recently, that speleothems can record past fire events due to physical and chemical processes which alter speleothem composition. These processes include changes to water stores due to evaporation, fracturing of the host rock, changed soil hydrophobicity, production of highly soluble lime, changes in soil CO2 production, destruction of vegetation and deposition of ash above the cave. These changes can result in shifts in & #948 O and & #948 C, altered concentrations of vegetation, soil and bedrock-derived elements, and incorporation of soluble ash derived elements (including phosphorus, aluminium, copper, zinc, and lead) in speleothems (McDonough et al., 2022 C bell et al., 2022).Changes in speleothem chemistry are typically determined using micro-analytical techniques (such as Synchrotron X-ray Fluorescence Microscopy and laser ablation inductively coupled plasma mass spectrometry) and isotope ratio mass spectrometry. These changes can be precisely and absolutely dated via uranium-series and carbon dating, and can often be resolved at high resolution via manual counting of seasonal fluctuations in organic matter and trace element concentration. This makes speleothems, particularly those grown in shallow caves in highly seasonal climates, ideal for identifying both short-lived events such as wildfires, and longer-term changes such as shifts in climate. This novel application of speleothems as archives for coupled climate and palaeofire proxies is still in its infancy but holds great potential.Here, we present a review of this new sub-discipline. We cover its origins in cave dripwater monitoring, discuss site and s le selection, and describe the current analytical and statistical approaches used to extract fire information from speleothems. Such records will enable land managers to develop improved methods for managing fire regimes. McDonough, L.K., Treble, P.C., Baker, A., Borsato, A., Frisia, S., Nagra, G., Coleborn, K., Gagan, M.K., Zhao, J., Paterson, D., 2022. Past fires and post-fire impacts reconstructed from a southwest Australian stalagmite. Geochimica et Cosmochimica Acta. 0.1016/j.gca.2022.03.020 & C bell, M., McDonough, L., Treble, P., Baker, A., Kosarac, N., Coleborn, K., Wynn, P.M., Schmitt, A., 2022. Speleothems as Archives for Palaeofire Proxies [preprint], oi/full/10.1002/essoar.10511989.1 &
Insights into recharge processes and speleothem proxy archives from long-term monitoring networks of cave drip water hydrology
Publisher: Copernicus GmbH
Date: 23-03-2020
DOI: 10.5194/EGUSPHERE-EGU2020-1686
Abstract: & & Since 2010 we have established cave drip water hydrological monitoring networks in four contrasting climate zones (Mediterranean, montane, semi-arid and sub-tropical) across continental Australia. Deploying over one hundred automated drip loggers, we combine these long-term monitoring datasets with climate and water isotope data, lidar mapping, electrical resistivity imaging and karst hydrological modelling to provide insights into recharge processes and the impact of hydrological variability on speleothem proxy archives.& & & & We identify increases in drip discharge and compare the timing of those events to antecedent climate conditions (rainfall, evapotranspiration). We find rainfall recharge thresholds vary with climate. At our montane site, recharge occurs after 13 to 31 mm rainfall events, depending on antecedent conditions. At the semi-arid site, recharge occurs after 40 mm rainfall events, and at our sub-tropical sites, recharge occurs following all instances where & 93 mm / week of precipitation occurs, with lower precipitation thresholds (down to 33 mm / week) possible depending on antecedent conditions and at sites with limited vegetation cover. We use these recharge thresholds to constrain simple soil moisture balance models to better understand soil and karst storage volumes. Combined with electrical resistivity imaging, we can relate recharge to the caves to subsurface water flow paths and karst water stores.& & & & At our montane and Mediterranean climate sites, relatively consistent drip water isotopic composition confirms the presence of well-mixed water stores. This allows us to quantify the extent of speleothem oxygen isotope variability due to fractionation associated with changes in drip rate. We identify significant differences in long-term mean drip rates between different drip sites within a cave, and significant differences in event-based drip rate responses within a cave. Drip hydrological variability helps explain the within-cave variability of speleothem oxygen isotope composition observed at both sites, and helps identify the primary drip water oxygen isotope signal.& & & & At our semi-arid site, drip water isotopic composition is dominated by epikarst evaporation and our drip water monitoring demonstrates that recharge events are infrequent (~1.6 per year). Using both observational and modelling data, we quantify the relative importance of evaporative fractionation in the epikarst and fractionation during calcite precipitation. Using modern speleothem s les, we demonstrate that the oxygen isotope signal in this water limited environment reflects the balance between the oxygen isotope composition of recharge and its subsequent fractionation in the soil, epikarst and cave.& &
Analysis of the Preserved Amino Acid Bias in Peptide Profiles of Iron Age Teeth from a Tropical Environment Enable Sexing of Individuals Using Amelogenin MRM
Publisher: Wiley
Date: 18-02-2019
Abstract: The first dental proteomic profile of Iron Age in iduals (ca. 2000-1000 years B.P.), collected from the site of Long Long Rak rock shelter in northwest Thailand is described. A bias toward the preservation of the positively charged aromatic, and polar amino acids is observed. It is evident that the 212 proteins identified (2 peptide, FDR <1%) comprise a palimpsest of alterations that occurred both ante-mortem and post-mortem. Conservation of amino acids within the taphonomically resistant crystalline matrix enabled the identification of both X and Y chromosome linked amelogenin peptides. A novel multiple reaction monitoring method using the sex specific amelogenin protein isoforms is described and indicate the teeth are of male origin. Functional analysis shows an enrichment of pathways associated with metabolic disorders and shows a capacity for harboring these conditions prior to death. Stable isotope analysis using carbon isotopes highlights the strongly C
Caves demonstrate decrease in rainfall recharge of southwest Australian groundwater is unprecedented for the last 800 years
Publisher: Springer Science and Business Media LLC
Date: 09-06-2023
DOI: 10.1038/S43247-023-00858-7
Abstract: Billions of people worldwide rely on groundwater. As rainfall in many regions in the future is projected to decrease, it is critical to understand the impacts of climate change on groundwater recharge. The groundwater recharge response to a sustained decrease in rainfall across southwest Australia that began in the late 1960s was examined in seven modern speleothems and drip waters from four caves. These show a pronounced increase or uptick in regional drip water and speleothem oxygen isotopic composition (δ 18 O) that is not driven by a change in rainfall δ 18 O values, but is in response to the shallow karst aquifers becoming disconnected from rainfall recharge due to regional drying. Our findings imply that rainfall recharge to groundwater may no longer be reliably occurring in this region, which is highly dependent on groundwater resources. Examination of the longer speleothem record shows that this situation is unprecedented over the last 800 years.
Applications of stalagmite laminae to paleoclimate reconstructions: Comparison with dendrochronology/climatology
Publisher: Elsevier BV
Date: 09-2006
Recharge variability in Australia's southeast alpine region derived from cave monitoring and modern stalagmite δ18O records
Publisher: Elsevier BV
Date: 11-2022
On-Line Solid Phase Extraction Using the Prospekt-2 Coupled with a Liquid Chromatography/Tandem Mass Spectrometer for the Determination of Dextromethorphan, Dextrorphan and Guaifenesin in Human Plasma
Publisher: SAGE Publications
Date: 04-2005
DOI: 10.1255/EJMS.737
Abstract: An on-line liquid chromatography/tandem mass spectrometry (LC-MS/MS) procedure, using the Prospekt-2 system, was developed and used for the determination of the levels of the active ingredients of cough/cold medications in human plasma matrix. The experimental configuration allows direct plasma injection by performing on-line solid phase extraction (SPE) on small cartridge columns prior to elution of the analyte(s) onto the analytical column and subsequent MS/MS detection. The quantitative analysis of three analytes with differing polarities, dextromethorphan (DEX), dextrorphan (DET) and guaifenesin (GG) in human plasma presented a significant challenge. Using stable-isotope-labeled internal standards for each analyte, the Prospekt-2 on-line methodology was evaluated for sensitivity, suppression, accuracy, precision, linearity, analyst time, analysis time, cost, carryover and ease of use. The lower limit of quantitation for the on-line SPE procedure for DEX, DET and GG was 0.05, 0.05 and 5.0 ng mL −1 , respectively, using a 0.1 mL s le volume. The linear range for DEX and DET was 0.05–50 ng mL −1 and was 5–5,000 ng mL −1 for GG. Accuracy and precision data for five different levels of QC s les were collected over three separate days. Accuracy ranged from 90% to 112% for all three analytes, while the precision, as measured by the %RSD, ranged from 1.5% to 16.0%.
Dynamics of water movement and trends in dissolved carbon in a headwater wetland in a permeable catchment
Publisher: Springer Science and Business Media LLC
Date: 12-2007
A fluorescence quenching study of the interaction of Suwannee River fulvic acid with iron oxide nanoparticles
Publisher: Elsevier BV
Date: 08-2009
DOI: 10.1016/J.CHEMOSPHERE.2009.04.067
Abstract: The fluorescence quenching behaviour of a manufactured nanoparticle (NP, iron oxide, 7nm) on the standard Suwannee River fulvic acid (SRFA) was investigated for the first time. Size, aggregation and fluorescence was examined as a function of NP:SRFA ratio and of pH. Aggregation state varied as both a function of pH and NP:SRFA ratio, with maximum aggregation at near neutral pH values (6-8). SRFA fluorescence quenching increased non-linearly with increasing NP concentrations (>0.22x10(-3)M iron nanoparticles), indicating the complex nature of NP:SRFA interactions. Aggregates of iron oxide present at pH7-8 appeared to have a much larger effect on quenching compared with dispersed NPs or dissolved phase iron. Fluorescence quenching is demonstrated to indicate different mechanisms of NP:SRFA binding with pH.
Field Measurement of Fluorescent Dissolved Organic Material as a Means of Early Detection of Leachate Plumes
Publisher: Springer Science and Business Media LLC
Date: 17-06-2015
Evolution of chemical and isotopic composition of inorganic carbon in a complex semi-arid zone environment: Consequences for groundwater dating using radiocarbon
Publisher: Elsevier BV
Date: 09-2016
A Review of Speleothems as Archives for Paleofire Proxies, With Australian Case Studies
Publisher: American Geophysical Union (AGU)
Date: 04-2023
DOI: 10.1029/2022RG000790
Abstract: Wildfires affect 40% of the earth's terrestrial biome, but much of our knowledge of wildfire activity is limited to the satellite era. Improved understanding of past fires is necessary to better forecast how fire regimes might change with future climate change, to understand ecosystem resilience to fire, and to improve data‐model comparisons. Environmental proxy archives can extend our knowledge of past fire activity. Speleothems, naturally occurring cave formations, are widely used in paleoenvironmental research as they are absolutely dateable, occur on every ice‐free continent, and include multiple proxies. Recently, speleothems have been shown to record past fire events (Argiriadis et al., 2019, 0.1021/acs.analchem.9b00767 McDonough et al., 2022, 0.1016/j.gca.2022.03.020 Homann et al., 2022, 0.1038/s41467-022-34950-x ). Here we present a review of this emerging application in speleothem paleoenvironmental science. We give a concise overview of fire regimes and common paleofire proxies, describe past attempts to use stalagmites to investigate paleofire, and describe the physical basis through which speleothems can record past fires. We then describe the ideal speleothem s le for paleofire research and offer a summary of applicable laboratory and statistical methods. Finally, we present four case studies from southwest Australia which: (a) explore the geochemistry of ash leachates, (b) detail how sulfate isotopes may be a proxy for post fire ecological recovery, (c) demonstrate how a catastrophic paleofire was linked to changes in climate and land management, and (d) investigate whether deep caves can record past fire events. We conclude the paper by outlining future research directions for paleofire applications.
Implications of multi-modal age distributions in Pleistocene cave deposits: A case study of Maludong palaeoathropological locality, southern China
Publisher: Elsevier BV
Date: 06-2019
Liquid-phase water isotope separation using graphene-oxide membranes
Publisher: Elsevier BV
Date: 2022
Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer
Publisher: Copernicus GmbH
Date: 12-02-2019
Abstract: Abstract. The terrestrial sub-surface is the largest source of freshwater globally. The organic carbon contained within it and processes controlling its concentration remain largely unknown. The global median concentration of dissolved organic carbon in groundwater is low compared to surface waters suggesting significant processing in the subsurface. Yet the processes that remove this dissolved organic carbon (DOC) in groundwater are not fully understood. The purpose of this study was to investigate the different sources and processes influencing DOC in a shallow anoxic coastal aquifer. Uniquely, this study combines liquid chromatography organic carbon detection with inorganic (δ13CDIC) and organic (δ13CDOC) carbon isotope geochemical analyses, to fingerprint the various DOC sources that influence the concentration, carbon isotopic composition and character with distance from surface water sources, depth below surface and groundwater residence time (using 3H) in groundwater. It was found that the average groundwater DOC concentration was five times higher (5 mg L−1) than the global median concentration and it doubled with depth, but the chromatographic character did not change significantly. The anoxic saturated conditions of the aquifer have limited the rate of organic matter processing leading to enhanced preservation and storage of the sources such as peats and palaeosols. All groundwater s les are more aromatic for their molecular weight in comparison to lakes and rivers and surface marine s les. The destabilisation or changes in hydrology, whether by anthropogenic or natural processes could lead to the flux of up to ten times more unreacted organic carbon from this coastal aquifer than compared to deeper inland aquifers.
Decadal-scale rainfall variability in Ethiopia recorded in an annually laminated, Holocene-age, stalagmite
Publisher: SAGE Publications
Date: 12-07-2010
Abstract: An annually laminated, uranium-series dated, Holocene stalagmite from southeast Ethiopia has been analysed for growth rate and δ 13 C and δ 18 O variations at annual to biennial resolution, in order to provide the first long duration proxy record of decadal-scale rainfall variability in this climatically sensitive region. Our study site (10°N) is climatically influenced by both summer (June—August) and spring (March—May) rainfall caused by the annual movement of the Inter-Tropical Convergence Zone (ITCZ) and modulated by large-scale anomalies in the atmospheric circulation and in ocean temperatures. Here we show that stalagmite growth, episodic throughout the last 7800 years, demonstrates decadal-scale (8—25 yr) variability in both growth rate and δ 18 O. A hydrological model was employed and indicates that this decadal variability is due to variations in the relative amounts of rainfall in the two rain seasons. Our record, unique in its combination of length (a total of ~1000 years), annual chronology and high resolution δ 18 O, shows for the first time that such decadal-scale variability in rainfall in this region has occurred through the Holocene, which implies persistent decadal-scale variability for the large-scale atmospheric and oceanic driving factors.
Characterisation of groundwater dissolved organic matter using LCOCD: Implications for water treatment
Publisher: Elsevier BV
Date: 2021
Dripwater organic matter and trace element geochemistry in a semi-arid karst environment: Implications for speleothem paleoclimatology
Publisher: Elsevier BV
Date: 06-2014
Organic characterisation of cave drip water by LC-OCD and fluorescence analysis
Publisher: Elsevier BV
Date: 10-2015
To what extent do long-duration high-volume dam releases influence river–aquifer interactions? A case study in New South Wales, Australia,长期大容量水坝放水对河流-含水层相互作用的影响能到什么程度?澳大利亚新南威尔士州的一个研究实例,Dans quelle mesure les lâchers de barrages de longue durée et gros volume influencent-ils les interactions nappe–rivière? Une étude de cas en Nouvelle-Galles du Sud, Australie,Até que ponto as descargas de longa duração e grande volume de barragens influenciam as interações rio–aquífero? Um estudo de caso na Nova Gales do Sul, Austrália,En qué medida los vertidos de larga duración y alto volumen de los diques influyen en la interacción río–acuífero? Un estudio de caso en Nueva Gales del Sur, Australia
Publisher: Springer Science and Business Media LLC
Date: 20-11-2015
Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination
Publisher: Springer Science and Business Media LLC
Date: 05-01-2017
DOI: 10.1038/SREP39979
Abstract: Reconstructing the dynamic response of the Antarctic ice sheets to warming during the Last Glacial Termination (LGT 18,000–11,650 yrs ago) allows us to disentangle ice-climate feedbacks that are key to improving future projections. Whilst the sequence of events during this period is reasonably well-known, relatively poor chronological control has precluded precise alignment of ice, atmospheric and marine records, making it difficult to assess relationships between Antarctic ice-sheet (AIS) dynamics, climate change and sea level. Here we present results from a highly-resolved ‘horizontal ice core’ from the Weddell Sea Embayment, which records millennial-scale AIS dynamics across this extensive region. Counterintuitively, we find AIS mass-loss across the full duration of the Antarctic Cold Reversal (ACR 14,600–12,700 yrs ago), with stabilisation during the subsequent millennia of atmospheric warming. Earth-system and ice-sheet modelling suggests these contrasting trends were likely Antarctic-wide, sustained by feedbacks lified by the delivery of Circumpolar Deep Water onto the continental shelf. Given the anti-phase relationship between inter-hemispheric climate trends across the LGT our findings demonstrate that Southern Ocean-AIS feedbacks were controlled by global atmospheric teleconnections. With increasing stratification of the Southern Ocean and intensification of mid-latitude westerly winds today, such teleconnections could lify AIS mass loss and accelerate global sea-level rise.
Fluorescence of road salt additives: potential applications for residual salt monitoring
Publisher: IOP Publishing
Date: 12-12-2006
Passive Treatment of Mn-Rich Mine Water: Using Fluorescence to Observe Microbiological Activity
Publisher: Informa UK Limited
Date: 04-2005
A comprehensive review of technical aspects of biomass cookstoves
Publisher: Elsevier BV
Date: 04-2017
Northwest European palaeoclimate as indicated by growth frequency variations of secondary calcite deposits
Publisher: Elsevier BV
Date: 02-1993
Real-time detection of faecally contaminated drinking water with tryptophan-like fluorescence: defining threshold values
Publisher: Elsevier BV
Date: 05-2018
DOI: 10.1016/J.SCITOTENV.2017.11.162
Abstract: We assess the use of fluorescent dissolved organic matter at excitation-emission wavelengths of 280nm and 360nm, termed tryptophan-like fluorescence (TLF), as an indicator of faecally contaminated drinking water. A significant logistic regression model was developed using TLF as a predictor of thermotolerant coliforms (TTCs) using data from groundwater- and surface water-derived drinking water sources in India, Malawi, South Africa and Zambia. A TLF threshold of 1.3ppb dissolved tryptophan was selected to classify TTC contamination. Validation of the TLF threshold indicated a false-negative error rate of 15% and a false-positive error rate of 18%. The threshold was unsuccessful at classifying contaminated sources containing <10 TTC cfu per 100mL, which we consider the current limit of detection. If only sources above this limit were classified, the false-negative error rate was very low at 4%. TLF intensity was very strongly correlated with TTC concentration (ρ
Fluorescence characterization of cross flow ultrafiltration derived freshwater colloidal and dissolved organic matter
Publisher: Elsevier BV
Date: 07-2007
DOI: 10.1016/J.CHEMOSPHERE.2007.01.048
Abstract: 3-D fluorescence excitation-emission matrix (EEM) spectrophotometry was applied to investigate the fluorescence characterization of colloidal organic matter (COM) and truly dissolved organic matter (DOM) from an urban lake and a rural river fractionated by the cross flow ultrafiltration (CFUF) process with a 1kDa membrane. Relatively high tryptophan-like fluorescence intensity is found in the urban water, although the fluorescence of both water s les is mainly dominated by humic/fulvic-like fluorophores. During CFUF processing, the fluorescence intensities of humic/fulvic-like materials in the retentate increased rapidly, but a slight increase is also observed in the permeate fluorescence intensity. Very different ultrafiltration behaviour occurred with respect to the tryptophan-like fluorophore, where both permeate and retentate fluorescence intensities increase substantially at the beginning of the CFUF process, then tend to remain constant at high concentration factor (cf) values. Comparison with tryptophan standards demonstrates that freshwater tryptophan-like fluorescence is not dissolved and 'free', but is, in part, colloidal and related to the ultrafiltration behaviour of fulvic/humic-like matter. A good linear relationship between the retentate humic/fulvic-like fluorescence intensity and organic carbon concentration further reveals that fluorescent humic/fulvic-like substances are the dominant contributors to colloidal organic carbon, mainly in the colloidal fraction.
Spatial variability of cave-air carbon dioxide and methane concentrations and isotopic compositions in a semi-arid karst environment
Publisher: Springer Science and Business Media LLC
Date: 04-2016
Corrigendum to “Late Holocene climate anomaly concurrent with fire activity and ecosystem shifts in the eastern Australian Highlands” [Sci. Total Environ. 802 (2021)149542](S0048969721046167)(10.1016/j.scitotenv.2021.149542)
Publisher: Elsevier BV
Date: 03-2022
Fluorescence monitoring at a recycled water treatment plant and associated dual distribution system - Implications for cross-connection detection
Publisher: Elsevier BV
Date: 10-2010
DOI: 10.1016/J.WATRES.2010.06.003
Abstract: Dual distribution systems are becoming increasingly common in greenfield housing developments in Australia for the redistribution of recycled water to households for non-potable use. Within such schemes there exists the potential for cross-connections between recycled and drinking water systems. Due to the high level of recycled water treatment, these events are unlikely to lead to outbreaks of illness in the community. Nonetheless, they do represent a breach of the recycled water risk management strategy and therefore an elevated level of risk to consumers. Furthermore, cross-connection events have the potential to undermine public confidence in these types of water recycling. A rapid, highly sensitive method of cross-connection detection may therefore provide an additional level of confidence in these schemes. The aim of this research was to determine the potential for using fluorescence spectroscopy as a monitoring tool in water treatment plants and dual distribution systems. S les from both the water recycling plant and dual distribution system were collected on a weekly basis over 12 weeks. Fluorescence excitation-emission matrix (EEM) spectra and water quality parameters including dissolved organic carbon, UV(254), pH, conductivity, free chlorine and turbidity were obtained for each s le. The fluorescence EEM spectra of recycled and drinking water were distinctly different and exhibited low variability throughout the course of the s ling program, indicating a degree of stability of the fluorescent components within the organic matter. A ten-fold difference in mean fluorescence intensity was observed for recycled water compared to drinking water, which was greater than the difference observed for the other measured water quality parameters. Probabilistic analysis was used to determine the reliable detection limit of recycled water contamination of drinking water. Accounting for the inherent variability of both recycled water and drinking water, a 45% contamination of recycled water in drinking water could be detected with a signal-to-noise ratio greater than 3 for more than 95% of in idual random s le pairs. Greater sensitivity can be assured by averaging numerous s les. In comparison, a 70% contamination of recycled water in drinking water was required for the same detection using conductivity.
Reconstruction of cave air temperature based on surface atmosphere temperature and vegetation changes: Implications for speleothem palaeoclimate records
Publisher: Elsevier BV
Date: 05-2013
Paleoclimate change in Ethiopia around the last interglacial derived from annually-resolved stalagmite evidence
Publisher: Elsevier BV
Date: 12-2018
Studies of Cave Sediments: Physical and Chemical Records of Paleoclimate (Revised Edition)
Publisher: American Geophysical Union (AGU)
Date: 16-10-2007
DOI: 10.1029/2007EO420014
Estimation of deep infiltration in unsaturated limestone environments using cave LiDAR and drip count data
Publisher: Copernicus GmbH
Date: 02-09-2015
DOI: 10.5194/HESSD-12-8891-2015
Abstract: Abstract. Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management and for stalagmite-based paleoclimate reconstructions. Caves offer a natural inception point to observe both the long-term groundwater recharge and the preferential movement of water through the unsaturated zone of such limestone. With the availability of automated drip rate logging systems and remote sensing techniques, it is now possible to deploy the combination of these methods for larger scale studies of infiltration processes within a cave. In this study, we utilize a spatial survey of automated cave drip monitoring in two large chambers of the Golgotha Cave, South-West Western Australia (SWWA), with the aim of better understanding infiltration water movement and the relationship between infiltration, stalactite morphology and unsaturated zone recharge. By applying morphological analysis of ceiling features from Terrestrial LiDAR (T-LiDAR) data, coupled with drip time series and climate data from 2012–2014, we demonstrate the nature of the relationships between infiltration through fractures in the limestone and unsaturated zone recharge. Similarities between drip-rate time series are interpreted in terms of flow patterns, cave chamber morphology and lithology. Moreover, we develop a new technique to estimate recharge in large scale caves, engaging flow classification to determine the cave ceiling area covered by each flow category and drip data for the entire observation period, to calculate the total volume of cave discharge. This new technique can be applied to other cave sites to identify highly focused areas of recharge and can help to better estimate the total recharge volume.
Solar forced diurnal regulation of cave drip rates via phreatophyte evapotranspiration
Publisher: Copernicus GmbH
Date: 15-02-2016
DOI: 10.5194/HESS-2016-11
Abstract: Abstract. We present results of a detailed study of drip rate variations at 12 drip discharge sites in Glory Hole Cave, New South Wales, Australia. Our novel time series analysis, using the synchrosqueeze transform, reveals pronounced oscillations at daily and sub-daily frequencies occurring in 8 out of the 12 monitored sites. These oscillations were not spatially or temporally homogenous, with different drip sites exhibiting such behaviour at different times of year in different parts of the cave. We test several hypotheses for the cause of the oscillations including variations in pressure gradients between karst and cave due to cave breathing effects or atmospheric and earth tides, variations in hydraulic conductivity due to changes in viscosity of water with daily temperature oscillations, and solar driven daily cycles of vegetative (phreatophytic) transpiration. We conclude that the only hypothesis consistent with the data and hydrologic theory is that daily oscillations are caused by solar driven pumping by phreatophytic trees which are abundant at the site. The daily oscillations are not continuous and occur sporadically in short bursts (2–14 days) throughout the year due to non-linear modification of the solar signal via complex karst architecture. This is the first observation of tree water use in cave drip water and has important implications for karst hydrology in regards to developing a new protocol to determine the relative importance of trends in drip rate at different timescales and to infer karst architecture. Our findings support a growing body of research exploring the impact of trees on speleothem paleoclimate proxies.
High-resolution sulphur isotope analysis of speleothem carbonate by secondary ionisation mass spectrometry
Publisher: Elsevier BV
Date: 03-2010
Geochemical records of palaeoenvironmental controls on peat forming processes in the Mfabeni peatland, Kwazulu Natal, South Africa since the Late Pleistocene
Publisher: Elsevier BV
Date: 02-2014
A composite annual-resolution stalagmite record of North Atlantic climate over the last three millennia
Publisher: Springer Science and Business Media LLC
Date: 11-06-2015
DOI: 10.1038/SREP10307
Abstract: Annually laminated stalagmites can be used to construct a precise chronology and variations in laminae thickness provide an annual growth-rate record that can be used as a proxy for past climate and environmental change. Here, we present and analyse the first composite speleothem annual growth-rate record based on five stalagmites from the same cave system in northwest Scotland, where precipitation is sensitive to North Atlantic climate variability and the winter North Atlantic Oscillation (NAO). Our 3000-year record confirms persistently low growth-rates, reflective of positive NAO states, during the Medieval Climate Anomaly (MCA). Another persistently low growth period occurring at 290-550 CE coincides with the European Migration Period and a subsequent period of sustained fast growth-rate (negative NAO) from 600-900 AD provides the climate context for the Viking Age in northern and western Europe.
A three thousand year record of North Atlantic climate
Publisher: Springer Science and Business Media LLC
Date: 08-2002
Changes in global groundwater organic carbon driven by climate change and urbanization
Publisher: Springer Science and Business Media LLC
Date: 09-03-2020
DOI: 10.1038/S41467-020-14946-1
Abstract: Climate change and urbanization can increase pressures on groundwater resources, but little is known about how groundwater quality will change. Here, we use a global synthesis ( n = 9,404) to reveal the drivers of dissolved organic carbon (DOC), which is an important component of water chemistry and substrate for microorganisms that control biogeochemical reactions. Dissolved inorganic chemistry, local climate and land use explained ~ 31% of observed variability in groundwater DOC, whilst aquifer age explained an additional 16%. We identify a 19% increase in DOC associated with urban land cover. We predict major groundwater DOC increases following changes in precipitation and temperature in key areas relying on groundwater. Climate change and conversion of natural or agricultural areas to urban areas will decrease groundwater quality and increase water treatment costs, compounding existing constraints on groundwater resources.
Strength of the winter North Atlantic jet stream has deviated from its natural trend under anthropogenic warming
Publisher: Geological Society of America
Date: 03-10-2023
DOI: 10.1130/G51329.1
Comments on PARAFAC and fluorescence from Andy Baker, UNSW Sydney
Publisher: Copernicus GmbH
Date: 20-01-2017
Determination of changes in wastewater quality through a treatment works using fluorescence spectroscopy
Publisher: Informa UK Limited
Date: 12-2013
DOI: 10.1080/09593330.2013.803131
Abstract: Fluorescence spectroscopy was used to characterize municipal wastewater at various stages of treatment in order to understand how its fluorescence signature changes with treatment and how the signal relates to biochemical oxygen demand (BOD) and chemical oxygen demand (COD). The impact of size fractionation on the fluorescence signal was also investigated. Fluorescence measurements were taken for unfiltered and filtered (0.45 and 0.20 microm) s les of crude, settled and secondary treated wastewater (activated sludge and trickling filter), and final effluent. Good correlations were observed for unfiltered, diluted wastewater s les between BOD and fluorescence intensity at excitation 280 nm, emission 350 nm (Peak T1) (r = 0.92) and between COD and Peak T1 intensity (r = 0.85). The majority of the T1 and T2 signal was found to be derived from the <0.20 microm fraction. Initial results indicate that fluorescence spectroscopy, and changes in Peak T1 intensity in particular, could be used for continuous, real-time wastewater quality assessment and process control of wastewater treatment works.
Modern speleothem oxygen isotope hydroclimate records in water-limited SE Australia
Publisher: Elsevier BV
Date: 02-2020
Spatiotemporal Variation in Cave Percolation Waters: A Functional Approach
Publisher: California Digital Library (CDL)
Date: 28-06-2023
DOI: 10.31223/X5Q08Z
Abstract: Understanding the mechanisms controlling spatial heterogeneity of drip water percolation into caves is essential for interpreting karst aquifer recharge and speleothem isotopic and geochemical records for paleoclimate analyses. Here we present the first analysis of drip rate variability using a novel time-varying Functional Principal Component Analysis (FPCA), validated against drip water stable isotope composition. Twenty-six drip sites were monitored across Harrie Wood Cave, south-east Australia, over a 2.5 year period. A positive relationship with cave drip water hydrology and rainfall and soil moisture was identified, with soil moisture recording the strongest relationship. FPCA was used to classify drip-water flow (percolation) pathways based on temporal shifts in the drip rate time series. Our results reveal that three percolation classes can be used to explain water movement within the cave: storage baseflow, fracture baseflow and overflow. The successful application of FPCA in this study suggests that this statistical technique will be useful for the analysis and interpretation of other large, discontinuous hydrological datasets.
Fluorescence Excitation−Emission Matrix Characterization of River Waters Impacted by a Tissue Mill Effluent
Publisher: American Chemical Society (ACS)
Date: 26-02-2002
DOI: 10.1021/ES0101328
Abstract: Fluorescence excitation-emission matrix (EEM) spectrophotometry was applied to five neighboring rivers, including one that is impacted by wastewater from a large tissue mill, to determine if fluorescence spectrophotometry could be used to differentiate between the river waters. River water s les from both the tissue mill effluent and the impacted river, the Park Burn, exhibited significantly higher fluorescence intensity than the other sites. This fluorescence was dominated by tryptophan fluorescence and a fluorescence center possibly due to the presence of fluorescent whitening agents. In contrast, the three other rivers exhibited lower fluorescence intensities typical of river systems with tryptophan (sewage), humic-like (peat derived color), and fulvic-like (natural organic matter) sources. It is suggested that fluorescence EEM spectrophotometry has the potential to provide a useful tool for pollution detection, monitoring, and control of paper industry impacts on river systems.
Terrestrial LiDAR Survey and Morphological Analysis to Identify Infiltration Properties in the Tamala Limestone, Western Australia
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 10-2015
Speleothems as Archives for Palaeofire Proxies
Publisher: Wiley
Date: 26-07-2022
Fluorescence Tracing of Diffuse Landfill Leachate Contamination in Rivers
Publisher: Springer Science and Business Media LLC
Date: 05-2005
Relating dissolved organic matter fluorescence and functional properties
Publisher: Elsevier BV
Date: 12-2008
DOI: 10.1016/J.CHEMOSPHERE.2008.09.018
Abstract: The fluorescence excitation-emission matrix properties of 25 dissolved organic matter s les from three rivers and one lake are analysed. All sites are s led in duplicate, and the 25 s les include ten taken from the lake site, and nine from one of the rivers, to cover variations in dissolved organic matter composition due to season and river flow. Fluorescence properties are compared to the functional properties of the dissolved organic matter the functional assays provide quantitative information on photochemical fading, buffering capacity, copper binding, benzo[a]pyrene binding, hydrophilicity and adsorption to alumina. Optical (absorbance and fluorescence) characterization of the dissolved organic matter s les demonstrates that (1) peak C (excitation 300-350 nm emission 400-460 nm) fluorescence emission wavelength (2) the ratio of peak T (excitation 220-235 nm emission 330-370 nm) to peak C fluorescence intensity and (3) the peak C fluorescence intensity: absorbance at 340 nm ratio have strong correlations with many of the functional assays. Strongest correlations are with benzo[a]pyrene binding, alumina adsorption, hydrophilicity and buffering capacity, and in many cases linear regression equations with a correlation coefficient >0.8 are obtained. These optical properties are independent of freshwater dissolved organic carbon concentration (for concentrations <10 mg L(-1)) and therefore hold the potential for laboratory, field and on-line monitoring and prediction of organic matter functional properties.
Stalagmite evidence for Early Holocene multidecadal hydroclimate variability in Ethiopia
Publisher: California Digital Library (CDL)
Date: 22-09-2021
DOI: 10.31223/X5SW5D
Abstract: A multiproxy oxygen and carbon isotope (d13C and d18O), growth rate and trace element stalagmite paleoenvironmental record is presented for the Early Holocene from Achere Cave, Ethiopia. The annually laminated stalagmite grew from 10.6 to 10.4 ka, and from 9.7 to 9.0 ka with a short hiatus at ~9.25 ka. Using oxygen and carbon isotopic, and cave monitoring data, we demonstrate that the stalagmite deposition is out of isotopic equilibrium, yet trace element and isotope geochemistry is sensitive to hydroclimate variability. Variogram analysis of annual growth rate data suggests that this proxy can only contain hydroclimate information over less than 28-year timescales. Statistically significant and coherent spectral frequencies in d13C and d18O are observed at 15-25 and 19-23 years respectively. Combined with compelling evidence for deposition out of isotope equilibrium, the observed ~1 ‰ litude variability in stalagmite d18O is likely forced by non-equilibrium deposition, likely due to kinetic effects during the progressive degassing of CO2 from the water film during stalagmite formation. These frequencies are similar to the periodicity reported for Holocene stalagmite records from Ethiopian caves, suggesting that multidecadal variability in stalagmite d18O is typical. We hypothesise that a hydroclimate forcing, such as runs of one or more years of low annual rainfall, is likely to be the primary control on the extent of the partial evaporation of soil and shallow epikarst water, which is subsequently modulated by karst hydrology, and the extent of in-cave non-equilibrium stalagmite deposition. Combined with possible recharge-biases in drip water d18O, modulated by karst hydrology, these processes can generate multidecadal d18O variability which can operate with opposite signs. Comparison of Early Holocene d18O stalagmite records from the monsoon regions of Ethiopia, Oman and central China show different multi-decadal d18O signals, implying regional difference in climate forcing. Seismic activities due to the active tectonics in the region control the frequency of growth gaps (hiatuses) by changing the water flow paths to the stalagmite.
Quantifying the value of laminated stalagmites for paleoclimate reconstructions
Publisher: American Geophysical Union (AGU)
Date: 03-2012
DOI: 10.1029/2012GL050986
Modelling karst vadose zone hydrology and its relevance for paleoclimate reconstruction
Publisher: Elsevier BV
Date: 09-2017
Fluorescence analysis of dissolved organic matter in natural, waste and polluted waters—a review
Publisher: Wiley
Date: 03-04-2007
DOI: 10.1002/RRA.1005
A new conceptual framework for the transformation of groundwater dissolved organic matter
Publisher: Springer Science and Business Media LLC
Date: 20-04-2022
DOI: 10.1038/S41467-022-29711-9
Abstract: Groundwater comprises 95% of the liquid fresh water on Earth and contains a erse mix of dissolved organic matter (DOM) molecules which play a significant role in the global carbon cycle. Currently, the storage times and degradation pathways of groundwater DOM are unclear, preventing an accurate estimate of groundwater carbon sources and sinks for global carbon budgets. Here we reveal the transformations of DOM in aging groundwater using ultra-high resolution mass spectrometry combined with radiocarbon dating. Long-term anoxia and a lack of photodegradation leads to the removal of oxidised DOM and a build-up of both reduced photodegradable formulae and aerobically biolabile formulae with a strong microbial signal. This contrasts with the degradation pathway of DOM in oxic marine, river, and lake systems. Our findings suggest that processes such as groundwater extraction and subterranean groundwater discharge to oceans could result in up to 13 Tg of highly photolabile and aerobically biolabile groundwater dissolved organic carbon released to surface environments per year, where it can be rapidly degraded. These findings highlight the importance of considering groundwater DOM in global carbon budgets.
Organic acid fluorescence: applications to speleothem palaeoenvironmental reconstruction
Publisher: Elsevier BV
Date: 07-2000
Application of Portable Fluorescence Spectrophotometry for Integrity Testing of Recycled Water Dual Distribution Systems
Publisher: SAGE Publications
Date: 2015
DOI: 10.1366/14-07513
Abstract: Water utilities supplying recycled water to households via a “third-pipe” or “dual reticulation” system have a need for a rapid, portable method to detect cross-connections within potable water reticulation networks. This study evaluates portable fluorimetry as a technique for cross-connection detection in the field. For the first time, an investigation of a full-scale dual reticulation water-recycling network has been carried out to identify cross-connections using a portable fluorimeter. We determined that this can be carried out with a 3 mL water s le, and unlike methods that are currently in use for cross-connection detection, can be achieved quickly without disruption to water flow or availability within the network. It was also revealed that fluorescence trigger values could be established with high levels of confidence by s ling less than 2.5% of the network. Fluorescence analysis was also able to uncover a single, real cross-connection event. As such, this paper is a fundamental demonstration of fluorescence as a reliable, highly portable technique for cross-connection detection within dual reticulation water recycling networks and further establishes the abilities of fluorescence devices as valuable field instruments for water quality monitoring.
Characterisation and controls on mineral-sorbed organic matter from a variety of groundwater environments
Publisher: California Digital Library (CDL)
Date: 11-12-2019
Variability in luminescent lamination and initial 230Th/232Th activity ratios in a late Holocene stalagmite from northern Norway
Publisher: Elsevier BV
Date: 06-2009
Dissolved Organic Carbon Mobilisation in a Groundwater System Stressed by Pumping
Publisher: Springer Science and Business Media LLC
Date: 22-12-2015
DOI: 10.1038/SREP18487
Abstract: The concentration and flux of organic carbon in aquifers is influenced by recharge and abstraction and surface and subsurface processing. In this study groundwater was abstracted from a shallow fractured rock aquifer and dissolved organic carbon (DOC) was measured in observation bores at different distances from the abstraction bore. Groundwater abstraction at rates exceeding the aquifers yield resulted in increased DOC concentration up to 3,500 percent of initial concentrations. Potential sources of this increased DOC were determined using optical fluorescence and absorbance analysis. Groundwater fluorescent dissolved organic material (FDOM) were found to be a combination of terrestrial-derived humic material and microbial or protein sourced material. Relative molecular weight of FDOM within four metres of the abstraction well increased during the experiment, while the relative molecular weight of FDOM between four and ten metres from the abstraction well decreased. When the aquifer is not being pumped, DOC mobilisation in the aquifer is low. We hypothesise that the physical shear stress on aquifer materials caused by intense abstraction significantly increases the temporary release of DOC from sloughing of biofilms and release of otherwise bound colloidal and sedimentary organic carbon (SOC).
On-line monitoring of organic matter concentrations and character in drinking water treatment systems using fluorescence spectroscopy
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6EW00048G
Abstract: There is a need for a rapid and robust method of organic matter (OM) monitoring during drinking water treatment.
Isotopic archives of sulphate in speleothems
Publisher: Elsevier BV
Date: 05-2008
Climatic, hydrological and karst geological controls on groundwater recharge: the view from an Australian vadose zone cave observatory
Publisher: Wiley
Date: 18-01-2022
Spatial and seasonal variations in the composition of dissolved organic matter in a tropical catchment: the Lower Kinabatangan River, Sabah, Malaysia
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C5EM00462D
Abstract: Dissolved organic matter (DOM) was characterised in water s les s led in the Lower Kinabatangan River Catchment, Sabah, Malaysia between October 2009 and May 2010.
Corrigendum to “The impact of fire on the geochemistry of speleothem-forming drip water in a sub-alpine cave” (Science of the Total Environment (2018) 642 (408–420), (S0048969718319624), (10.1016/j.scitotenv.2018.05.310))
Publisher: Elsevier BV
Date: 06-2019
Modelling of dripwater hydrology and hydrogeochemistry in a weakly karstified aquifer (Bath, UK): Implications for climate change studies
Publisher: Elsevier BV
Date: 04-2006
Southern Ocean carbon sink enhanced by sea-ice feedbacks at the Antarctic Cold Reversal
Publisher: Springer Science and Business Media LLC
Date: 22-06-2020
Effects of wildfire on long-term soil CO2 concentration: implications for karst processes
Publisher: Springer Science and Business Media LLC
Date: 02-2016
A post-wildfire response in cave dripwater chemistry
Publisher: Copernicus GmbH
Date: 19-01-2016
DOI: 10.5194/HESS-2016-1
Abstract: Abstract. Cave environments are sensitive because surface environmental changes can affect both the isotopic composition and solute concentration of infiltrating cave dripwaters. These changes subsequently affect the speleothem geochemical record. One such agent of change is wildfire, however its effect on karst processes remains poorly understood. Using dripwater data from a shallow cave, at a forested site in southwest Australia, we provide a unique analysis of the post-wildfire effects on dripwater δ18O and solute concentrations. We analyse how wildfires affect on local controls, i.e. vegetation cover, evapotranspiration and carbonate water-rock interactions, effects cave dripwater hydrology and geochemistry. We compare our post-wildfire data with modelled drip water δ18O, regional groundwater chemistry, and a second cave dripwater dataset, to determine the extent to which wildfire affects cave dripwater composition. We find in our forested, shallow cave site, by effecting surface evaporation and transpiration rates wildfire can have a multi-year impact on subsurface hydrology and dripwater chemistry. Here we open a new avenue for speleothem science in fire-prone regions, focusing on the geochemical records of speleothems as potential paleo-fire archives.
Intra- and inter-annual growth rate of modern stalagmites
Publisher: Elsevier BV
Date: 07-2001
Island groundwater resources, impacts of abstraction and a drying climate: Rottnest Island, Western Australia
Publisher: Elsevier BV
Date: 11-2016
Separating isotopic impacts of karst and in-cave processes from climate variability using an integrated speleothem isotope-enabled forward model
Publisher: California Digital Library (CDL)
Date: 05-03-2019
Exploratory analysis of excitation‐emission matrix fluorescence spectra with self‐organizing maps as a basis for determination of organic matter removal efficiency at water treatment works
Publisher: American Geophysical Union (AGU)
Date: 12-2009
DOI: 10.1029/2009JG000940
Stalagmite lamina doublets: a 1000 year proxy record of severe winters in northwest Scotland?
Publisher: Wiley
Date: 2002
DOI: 10.1002/JOC.800
Fluorescence properties of some farm wastes: implications for water quality monitoring
Publisher: Elsevier BV
Date: 2002
DOI: 10.1016/S0043-1354(01)00210-X
Abstract: Some farm wastes have been analysed for their fluorescence properties using fluorescence excitation-matrix (EEM) spectroscopy. Farm wastes investigated were silage liquor, pig and cattle slurry, and sheep barn waste. All farm wastes exhibited high intensities of fluorescence that can be attributed to the protein tryptophan. Silage liquor was characterised by a very high fluorescence intensity and an initial tryptophan: fulvic-like fluorescence intensity ratio of >20. Cattle and pig slurries exhibited a lower tryptophan : fulvic-like fluorescence intensity ratio (approximately 2-5) and lower tryptophan fluorescence intensity, and tyrosine fluorescence was also observed. Sheep barn wastes had the lowest tryptophan: fulvic-like fluorescence intensity ratios (approximately 0.5-4.0). Farm waste s les were reanalysed under controlled temperature conditions over a period of 50 days after s ling, to investigate the stability of their fluorescence properties. For silage liquor. tryptophan: fulvic-like fluorescence intensity ratios were observed to decrease with time, and were associated with a decrease in tryptophan fluorescence intensity, suggestive of clostridia breakdown of protein. For slurry s les. tryptophan: fulvic-like fluorescence intensity exhibited a more variable time-evolution, and tryptophan fluorescence intensity increased through time the more complex fluorescence signal is due to the relatively heterogeneous nature of the slurry. Sheep barn waste s les exhibited more stable tryptophan: fulvic-like fluorescence intensity ratio and tryptophan intensities, suggesting these s les were more stable due to their greater age and decomposition. The ratios of tryptophan: fulvic-like fluorescence intensity observed from the farm wastes investigated are significantly higher than those observed in the majority of river waters, suggesting that farm waste pollution events could leave a signature in river waters due to their distinctively high protein fluorescence intensity.
Fluorescence monitoring for cross-connection detection in water reuse systems: Australian case studies
Publisher: IWA Publishing
Date: 2010
DOI: 10.2166/WST.2010.795
Abstract: A rapid, highly sensitive method for detection of cross-connections between recycled and potable water in dual reticulation systems is required. The aim of this research was to determine the potential of fluorescence spectroscopy as a monitoring tool at three Australian dual distribution (drinking and recycled water) systems. Weekly grab s les of recycled and potable water were obtained over 12 weeks at each site and analysed for fluorescence excitation-emission matrix (EEM) spectroscopy, UV254, dissolved organic carbon (DOC), electrical conductivity and pH. Fluorescence EEM spectroscopy was able to differentiate between recycled and potable water at each site by monitoring the protein-like fluorescence at peak T—an excitation-emission wavelength pair of λex/em = 300/350 nm. While electrical conductivity was also able to distinguish between recycled and potable water, the differentiation was greatest when using fluorescence. For ex le, the peak T fluorescence in recycled water was up to 10 times that of potable water in comparison with electrical conductivity that had a maximum 5 times differentiation. Furthermore, by comparing the protein-like fluorescence at peak T and humic-like fluorescence at peak A (λex/em = 235/426 nm), the three different recycled water systems were able to be differentiated. Overall, fluorescence shows promise as a monitoring tool for detecting cross-connections.
Relating freshwater organic matter fluorescence to organic carbon removal efficiency in drinking water treatment
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1016/J.SCITOTENV.2008.11.013
Abstract: Monthly raw and clarified water s les were obtained for 16 UK surface water treatment works. The fluorescence excitation-emission matrix (EEM) technique was used for the assessment of total organic carbon (TOC) removal and organic matter (OM) characterisation. The impact of algae presence in water on TOC removal, and its relationship with fluorescence, was analysed. Fluorescence peak C intensity was found to be a sensitive and reliable measure of OM content. Fluorescence peak C emission wavelength and peak T intensity (reflecting the degree of hydrophobicity and the microbial fraction, respectively) were found to characterize the OM the impact of both on TOC removal efficiency was apparent. OM fluorescence properties were shown to predict TOC removal, and identify spatial and temporal variations. Previous work indicates that the trihalomethane (THM) concentration of treated water can be predicted from the raw water TOC concentration. The simplicity, sensitivity, speed of analysis and low cost, combined with potential for incorporation into on-line monitoring systems, mean that fluorescence spectroscopy offers a robust analytical technique to be used in conjunction with, or in place of, other approaches to OM characterisation and THM formation prediction.
Continuous fluorescence excitation–emission matrix monitoring of river organic matter
Publisher: Elsevier BV
Date: 10-2010
DOI: 10.1016/J.WATRES.2010.06.036
Abstract: Real-time fluorescence monitoring has been mostly performed in marine systems, with little progress being made in the application of fluorescence excitation-emission matrix (EEM) spectroscopy, especially for freshwater monitoring. This paper presents a two weeks experiment where real-time fluorescence EEM data have been obtained for Bourn Brook, Birmingham, UK, using an in-situ fibre-optic probe. Fluorescence EEMs were measured every 3 min for two weeks, with control 'grab' s les every hour analyzed for fluorescence EEMs as well as pH, conductivity and dissolved organic carbon. Comparison of real-time and control s les showed an excellent agreement, with no evidence of fibre-optic probe fouling. EEMs of different character were identified using self-organizing maps, which demonstrated seven clusters of fluorescence EEMs which related to the intensity of fluorescence and relative intensities of peak T(1) and T(2) vs. peak C and peak A fluorescence. Fluorescence intensity of peaks A and C were observed to increase with rainfall, and a diesel pollution event was detected through an increase in T(2) fluorescence.
SISALv2: A comprehensive speleothem isotope database with multiple age-depth models
Publisher: Copernicus GmbH
Date: 27-10-2020
DOI: 10.5194/ESSD-12-2579-2020
Abstract: Abstract. Characterizing the temporal uncertainty in palaeoclimate records is crucial for analysing past climate change, correlating climate events between records, assessing climate periodicities, identifying potential triggers and evaluating climate model simulations. The first global compilation of speleothem isotope records by the SISAL (Speleothem Isotope Synthesis and Analysis) working group showed that age model uncertainties are not systematically reported in the published literature, and these are only available for a limited number of records (ca. 15 %, n=107/691). To improve the usefulness of the SISAL database, we have (i) improved the database's spatio-temporal coverage and (ii) created new chronologies using seven different approaches for age–depth modelling. We have applied these alternative chronologies to the records from the first version of the SISAL database (SISALv1) and to new records compiled since the release of SISALv1. This paper documents the necessary changes in the structure of the SISAL database to accommodate the inclusion of the new age models and their uncertainties as well as the expansion of the database to include new records and the quality-control measures applied. This paper also documents the age–depth model approaches used to calculate the new chronologies. The updated version of the SISAL database (SISALv2) contains isotopic data from 691 speleothem records from 294 cave sites and new age–depth models, including age–depth temporal uncertainties for 512 speleothems. SISALv2 is available at 0.17864/1947.256 (Comas-Bru et al., 2020a).
Platelet activating factor receptor acts to limit colitis-induced liver inflammation.
Publisher: Wiley
Date: 15-04-2020
Land Use and Water Quality
Publisher: Wiley
Date: 21-10-2006
DOI: 10.1002/0470848944.HSA195
Abstract: The literature investigating the relationship between land use and water quality is synthesized. It is demonstrated that although some general correlations between land use and water quality can be observed, in general the relationship is complex with correlations in in idual watersheds likely to be site or regionally specific. Land cover measurements discussed include land use, land cover, ecotone, buffer strip, and indices of landscape metrics, whereas water quality issues include spatial and temporal s ling strategies and the use of nonconservative tracers. Ex les of land use–water quality relationships are given for both the impacts of urbanization and the intensification of agriculture. A paucity of studies in developing countries and the need to advance models of land use–water quality relationships are highlighted.
Paleoclimate implications of mass spectrometric dating of a British flowstone
Publisher: Geological Society of America
Date: 1995
Luminescence variations in fast‐growing stalagmites from uppsala, sweden
Publisher: Informa UK Limited
Date: 12-2005
Characterisation of dissolved organic matter fluorescence properties by PARAFAC analysis and thermal quenching
Publisher: Elsevier BV
Date: 09-2014
DOI: 10.1016/J.WATRES.2014.05.013
Abstract: The fluorescence intensity of dissolved organic matter (DOM) in aqueous s les is known to be highly influenced by temperature. Although several studies have demonstrated the effect of thermal quenching on the fluorescence of DOM, no research has been undertaken to assess the effects of temperature by combining fluorescence excitation - emission matrices (EEM) and parallel factor analysis (PARAFAC) modelling. This study further extends previous research on thermal quenching by evaluating the impact of temperature on the fluorescence of DOM from a wide range of environmental s les, in the range 20 °C - 0 °C. Fluorescence intensity increased linearly with respect to temperature decrease at all temperatures down to 0 °C. Results showed that temperature affected the PARAFAC components associated with humic-like and tryptophan-like components of DOM differently, depending on the water type. The terrestrial humic-like components, C1 and C2 presented the highest thermal quenching in rural water s les and the lowest in urban water s les, while C3, the tryptophan-like component, and C4, a reprocessed humic-like component, showed opposite results. These results were attributed to the availability and abundance of the components or to the degree of exposure to the heat source. The variable thermal quenching of the humic-like components also indicated that although the PARAFAC model generated the same components across sites, the DOM composition of each component differed between them. This study has shown that thermal quenching can provide additional information on the characteristics and composition of DOM and highlighted the importance of correcting fluorescence data collected in situ.
Visualisation of luminescence excitation-emission timeseries: Palaeoclimate implications from a 10,000 year stalagmite record from Ireland
Publisher: American Geophysical Union (AGU)
Date: 15-07-2000
DOI: 10.1029/2000GL011380
Biomass effects on stalagmite growth and isotope ratios: A 20th century analogue from Wiltshire, England
Publisher: Elsevier BV
Date: 12-2005
Sulphate partitioning into calcite: Experimental verification of pH control and application to seasonality in speleothems
Publisher: Elsevier BV
Date: 04-2018
Dead carbon in stalagmites: carbonate bedrock paleodissolution vs. ageing of soil organic matter. Implications for 13 C variations in speleothems
Publisher: Elsevier BV
Date: 10-2001
A nation that rebuilds its soils rebuilds itself- an engineer's perspective
Publisher: Elsevier BV
Date: 06-2022
Characterisation of reverse osmosis permeates from municipal recycled water systems using fluorescence spectroscopy: Implications for integrity monitoring
Publisher: Elsevier BV
Date: 12-2012
Recent flowstone growth rates: Field measurements in comparison to theoretical predictions
Publisher: Elsevier BV
Date: 05-1995
Continuous fluorescence assessment of organic matter variability on the Bournbrook River, Birmingham, UK
Publisher: Wiley
Date: 30-06-2009
DOI: 10.1002/HYP.7335
Glycerol dialkyl glycerol tetraethers (GDGT) distributions from soil to cave: Refining the speleothem paleothermometer
Publisher: Elsevier BV
Date: 10-2019
Annual growth banding in a cave stalagmite
Publisher: Springer Science and Business Media LLC
Date: 08-1993
DOI: 10.1038/364518A0
Evaluating model outputs using integrated global speleothem records of climate change since the last glacial
Publisher: Copernicus GmbH
Date: 09-08-2019
Abstract: Abstract. Although quantitative isotope data from speleothems has been used to evaluate isotope-enabled model simulations, currently no consensus exists regarding the most appropriate methodology through which to achieve this. A number of modelling groups will be running isotope-enabled palaeoclimate simulations in the framework of the Coupled Model Intercomparison Project Phase 6, so it is timely to evaluate different approaches to using the speleothem data for data–model comparisons. Here, we illustrate this using 456 globally distributed speleothem δ18O records from an updated version of the Speleothem Isotopes Synthesis and Analysis (SISAL) database and palaeoclimate simulations generated using the ECHAM5-wiso isotope-enabled atmospheric circulation model. We show that the SISAL records reproduce the first-order spatial patterns of isotopic variability in the modern day, strongly supporting the application of this dataset for evaluating model-derived isotope variability into the past. However, the discontinuous nature of many speleothem records complicates the process of procuring large numbers of records if data–model comparisons are made using the traditional approach of comparing anomalies between a control period and a given palaeoclimate experiment. To circumvent this issue, we illustrate techniques through which the absolute isotope values during any time period could be used for model evaluation. Specifically, we show that speleothem isotope records allow an assessment of a model's ability to simulate spatial isotopic trends. Our analyses provide a protocol for using speleothem isotope data for model evaluation, including screening the observations to take into account the impact of speleothem mineralogy on δ18O values, the optimum period for the modern observational baseline and the selection of an appropriate time window for creating means of the isotope data for palaeo-time-slices.
Andy Baker, nominated in 2021 for sustained excellence in water and climate science, especially the use of chemical tracers including applications to speleothem palaeoclimatology
Publisher: Wiley
Date: 21-05-2022
Fluorescence Excitation−Emission Matrix Characterization of Some Sewage-Impacted Rivers
Publisher: American Chemical Society (ACS)
Date: 26-01-2001
DOI: 10.1021/ES000177T
Abstract: Fluorescence excitation-emission matrix (EEM) spectrophotometry was applied to 10 s le sites in six rivers in northeastern England, some of which were adversely impacted by sewage treatment works (STW) discharges, with the aim to investigate whether STW discharge has a significantly distinct fluorescence signature. Upstream, downstream, and STW discharge s les for two STWs demonstrated that treated sewage has a distinct fluorescence EEM, with high tryptophan and fulvic-like fluorescence intensities that are of approximately equal ratio. This signature could be seen in downstream s les. When all 10 s le locations were compared, two trend lines were apparent where STW impacted rivers plotted separately from the other s le locations. Fluorescence EEM signatures were compared to absorption at 254 nm and demonstrated to provide a better fingerprint of sewage-impacted water. It is suggested that fluorescence EEM spectrophotometry can provide a useful tool for the analysis of grab s les taken for both routine and investigative monitoring and has the potential for on-line monitoring of STW impacts on river systems.
Can fluorescence spectrometry be used as a surrogate for the Biochemical Oxygen Demand (BOD) test in water quality assessment? An example from South West England
Publisher: Elsevier BV
Date: 02-2008
DOI: 10.1016/J.SCITOTENV.2007.10.054
Abstract: The fluorescence intensities of tryptophan-like, tyrosine-like and humic-like materials were determined using excitation-emission-matrices (EEMs) for a wide range of s les including natural surface waters, sewage and industrial effluents and waters that have experienced known pollution events from the South West of England (n=469). Fluorescence intensities reported in arbitrary fluorescence units (AFU) were correlated with standard five day Biochemical Oxygen Demand (BOD(5)) values which were used as an indicator of the amount of biodegradable organic material present. Tryptophan-like fluorescence, which has been found to relate to the activity of the biological community, showed the strongest correlation with BOD(5). Fluorescence analysis of the tryptophan-like peak (excitation/emission wavelength region 275/340 nm) is found to provide an accurate indication of the presence, and relative proportions of bioavailable organic material present (natural or anthropogenic). It therefore provides an insight relating to its oxygen depleting potential. Thus fluorescence spectroscopy is recommended as a portable or laboratory tool for the determination of the presence of biodegradable organic matter with intrinsic oxidising potential in natural waters. The novel application of Geographically Weighted Regression (GWR) to the data illustrates that strong local relationships exist between the two parameters and that site specific character may be a strong factor in the strength of the tryptophan-like fluorescence/BOD(5) relationship.
Direct stable isotope porewater equilibration and identification of groundwater processes in heterogeneous sedimentary rock
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.SCITOTENV.2015.08.075
Abstract: The off-axis integrated cavity output spectrometry (ICOS) method to analyse porewater isotopic composition has been successfully applied over the last decade in groundwater studies. This paper applies the off-axis ICOS method to analyse the porewater isotopic composition, attempts to use the isotopic shift in groundwater values along with simple geochemical mixing model to define the groundwater processes in the Sydney Basin, Australia. Complementary data included geophysical, hydrogeological, geochemical, and mineralogical investigations. Porewater from core s les were analysed for δ(18)O and δ(2)H from various sedimentary units in the Basin and compared to endpoint water members. Stable δ(18)O and δ(2)H values of porewaters in the Basin (-9.5 to 2.8‰ for δ(18)O and -41.9 to 7.9‰ for δ(2)H) covered a relatively narrow range in values. The variability in water isotopes reflects the variability of the input signal, which is the synoptic variability in isotopic composition of rainfall, and to a minor extent the subsequent evaporation. The porosity, bulk density and mineralogy data demonstrate the heterogeneity that adds the complexity to variations in the isotope profile with depth. The source of chloride in the sedimentary sequence was related to rock-water and cement/matrix-water interaction rather than to evaporation. The heterogeneous character of the sedimentary rock strata was supported by a change in pore pressures between units, density and variability in rock geochemical analyses obtained by using X-ray fluorescence (XRF) and X-ray power diffraction analyses. This research identified distinct hydrogeological zones in the Basin that were not previously defined by classic hydrogeological investigations. Isotopic signature of porewaters along the detailed vertical profile in combination with mineralogical, geochemical, geophysical and hydrogeological methods can provide useful information on groundwater movement in deep sedimentary environments. The findings of the study are valuable in management of sensitive ecosystems and potable resources above mining areas.
Late Holocene climate anomaly concurrent with fire activity and ecosystem shifts in the eastern Australian Highlands
Publisher: Elsevier BV
Date: 2022
Past fires and post-fire impacts reconstructed from a southwest Australian stalagmite
Publisher: Elsevier BV
Date: 05-2022
Assessing Connectivity Between an Overlying Aquifer and a Coal Seam Gas Resource Using Methane Isotopes, Dissolved Organic Carbon and Tritium
Publisher: Springer Science and Business Media LLC
Date: 04-11-2015
DOI: 10.1038/SREP15996
Abstract: Coal seam gas (CSG) production can have an impact on groundwater quality and quantity in adjacent or overlying aquifers. To assess this impact we need to determine the background groundwater chemistry and to map geological pathways of hydraulic connectivity between aquifers. In south-east Queensland (Qld), Australia, a globally important CSG exploration and production province, we mapped hydraulic connectivity between the Walloon Coal Measures (WCM, the target formation for gas production) and the overlying Condamine River Alluvial Aquifer (CRAA), using groundwater methane (CH 4 ) concentration and isotopic composition (δ 13 C-CH 4 ), groundwater tritium ( 3 H) and dissolved organic carbon (DOC) concentration. A continuous mobile CH 4 survey adjacent to CSG developments was used to determine the source signature of CH 4 derived from the WCM. Trends in groundwater δ 13 C-CH 4 versus CH 4 concentration, in association with DOC concentration and 3 H analysis, identify locations where CH 4 in the groundwater of the CRAA most likely originates from the WCM. The methodology is widely applicable in unconventional gas development regions worldwide for providing an early indicator of geological pathways of hydraulic connectivity.
Integrating multiple scales of hydraulic conductivity measurements in training image-based stochastic models
Publisher: American Geophysical Union (AGU)
Date: 2015
DOI: 10.1002/2014WR016150
Spatially dense drip hydrological monitoring and infiltration behaviour at the Wellington Caves, South East Australia
Publisher: University of South Florida Libraries
Date: 07-2012
Evaporative cooling of speleothem drip water
Publisher: Springer Science and Business Media LLC
Date: 04-06-2014
DOI: 10.1038/SREP05162
Abstract: This study describes the first use of concurrent high-precision temperature and drip rate monitoring to explore what controls the temperature of speleothem forming drip water. Two contrasting sites, one with fast transient and one with slow constant dripping, in a temperate semi-arid location (Wellington, NSW, Australia), exhibit drip water temperatures which deviate significantly from the cave air temperature. We confirm the hypothesis that evaporative cooling is the dominant, but so far unattributed, control causing significant disequilibrium between drip water and host rock/air temperatures. The amount of cooling is dependent on the drip rate, relative humidity and ventilation. Our results have implications for the interpretation of temperature-sensitive, speleothem climate proxies such as δ 18 O, cave microecology and the use of heat as a tracer in karst. Understanding the processes controlling the temperature of speleothem-forming cave drip waters is vital for assessing the reliability of such deposits as archives of climate change.
The estuarine mixing behaviour of peatland derived dissolved organic carbon and its relationship to chromophoric dissolved organic matter in two North Sea estuaries (U.K.)
Publisher: Elsevier BV
Date: 08-2007
The freshwater dissolved organic matter fluorescence-total organic carbon relationship
Publisher: Wiley
Date: 2007
DOI: 10.1002/HYP.6371
An annually resolved stalagmite record of fire frequency for the last 250 years in south west Australia
Publisher: Copernicus GmbH
Date: 15-05-2023
DOI: 10.5194/EGUSPHERE-EGU23-10651
Abstract: Stalagmites provide records of past changes in climate, vegetation, and surface events, which can be identified through variability in their chemical composition over time. This variability is the result of changes in surface environmental properties, which are reflected in the physical and chemical properties of the water that percolates into the cave, ultimately affecting the composition of the speleothem calcite. Wildfires have the potential to alter soil properties and soluble element concentrations. Consequently, stalagmite compositions have been shown to respond to increases in soil nutrients, trace metal concentrations, and changes in soil/karst bedrock hydraulic conductivity. It is, therefore, likely that stalagmites, and particularly those grown in shallow caves for which transmission of the surface signal is rapid, capture the environmental effects of wildfires in their chemical and physical properties.We analysed a stalagmite from a shallow cave in a region known to be affected by wildfires in south-west Western Australia. Fire proxies were assessed using a multi-proxy approach. This includes water isotopes via stable-isotope ratio mass spectrometry and trace element analyses via synchrotron X-ray fluorescence microscopy and laser ablation inductively coupled plasma mass spectrometry. This approach shows that the timing of known fire events coincided with a multi-proxy response in stalagmite chemistry, including increased concentrations of phosphorus, copper, aluminium, lead, and zinc, which are interpreted to be derived from leaching of ash from burned vegetation above the cave. We also identified lower and less variable peaks in phosphorus concentrations during the pre-colonisation period, suggesting that Indigenous land management resulted in more frequent but low intensity burning. This contrasted with less frequent but more intense fires associated with post-colonisation land-management. A particularly large paleo-fire identified in 1897 appears to coincide with a peak in & #120575 O, interpreted to have resulted from evaporation of sub-surface water during the heat of the fire. This large fire was preceded by a multi-decadal dry period identified by trace element proxies. The intensity of the 1897 fire was then exacerbated by the combination of a multi-decadal drought and a transition away from cultural burning practices by Indigenous Australians, which resulted in build-up of vegetation and dry combustible material on the forest floor.This research is a world-first demonstration of fire events recorded in stalagmites and shows their potential to provide accurate records of both fire frequency intervals and changes in climate. Further records of past fire events from stalagmites will help to understand how past fire regimes have varied with climate, land-use change and colonisation, and will help to better guide land management practices in the future.
The application of fluorescence spectroscopy to organic matter characterisation in drinking water treatment
Publisher: Springer Science and Business Media LLC
Date: 12-08-2011
Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia
Publisher: Copernicus GmbH
Date: 06-02-2018
Abstract: Abstract. Cave drip water response to surface meteorological conditions is complex due to the heterogeneity of water movement in the karst unsaturated zone. Previous studies have focused on the monitoring of fractured rock limestones that have little or no primary porosity. In this study, we aim to further understand infiltration water hydrology in the Tamala Limestone of SW Australia, which is Quaternary aeolianite with primary porosity. We build on our previous studies of the Golgotha Cave system and utilize the existing spatial survey of 29 automated cave drip loggers and a lidar-based flow classification scheme, conducted in the two main chambers of this cave. We find that a daily s ling frequency at our cave site optimizes the capture of drip variability with the least possible s ling artifacts. With the optimum s ling frequency, most of the drip sites show persistent autocorrelation for at least a month, typically much longer, indicating le storage of water feeding all stalactites investigated. Drip discharge histograms are highly variable, showing sometimes multimodal distributions. Histogram skewness is shown to relate to the wetter-than-average 2013 hydrological year and modality is affected by seasonality. The hydrological classification scheme with respect to mean discharge and the flow variation can distinguish between groundwater flow types in limestones with primary porosity, and the technique could be used to characterize different karst flow paths when high-frequency automated drip logger data are available. We observe little difference in the coefficient of variation (COV) between flow classification types, probably reflecting the le storage due to the dominance of primary porosity at this cave site. Moreover, we do not find any relationship between drip variability and discharge within similar flow type. Finally, a combination of multidimensional scaling (MDS) and clustering by k means is used to classify similar drip types based on time series analysis. This clustering reveals four unique drip regimes which agree with previous flow type classification for this site. It highlights a spatial homogeneity in drip types in one cave chamber, and spatial heterogeneity in the other, which is in agreement with our understanding of cave chamber morphology and lithology.
Characterization of Dissolved Organic Matter from Agricultural and Livestock Effluents: Implications for Water Quality Monitoring
Publisher: MDPI AG
Date: 14-03-2023
Abstract: There is growing concern about the impact of agricultural practices on water quality. The loss of nutrients such as nitrogen and phosphorous through agricultural runoff poses a potential risk of water quality degradation. However, it is unclear how dissolved organic matter (DOM) composition is associated with pollution levels in water bodies. To address this, we conducted a cross-year investigation to reveal the nature of DOM and its relationship to water quality in agricultural effluents (AEs) and livestock effluents (LEs). We discovered that DOM fluorescence components of AEs were mainly from autochthonous and terrestrial sources, while in LEs it was primarily from autochthonous sources. LEs showed a higher β:α and biological index (BIX) than AEs, indicating that LEs had higher biological activity. Compared to the LEs, DOM in AEs exhibited a higher humification index (HIX), illustrating that DOM was more humic and aromatic. Overall, our results suggest that the BIX and fluorescence index (FI) were best suited for the characterization of water bodies impacted by LEs and AEs. Excitation–emission matrix spectroscopy and parallel factor (EEMs-PARAFAC) analysis showed that DOM in AEs was mainly a humic-like material (~64%) and in LEs was mainly protein-like (~68%). Tryptophan-like compounds (C1) were made more abundant in AEs because of the breakdown of aquatic vegetation. The microbial activity enhanced protein-like substances (C1 and C2) in LEs. Our study revealed a positive correlation between five-day biochemical oxygen demand (BOD5) concentrations and tyrosine-like substance components, suggesting that fluorescence peak B may be a good predictor of water quality affected by anthropogenic activities. For both LEs and AEs, our results suggest that peak D may be a reliable water quality surrogate for total phosphorus (TP).
Rainfall recharge thresholds in a subtropical climate determined using a regional cave drip water monitoring network
Publisher: Elsevier BV
Date: 08-2020
Hydrological and geochemical responses of fire in a shallow cave system
Publisher: Elsevier BV
Date: 04-2019
DOI: 10.1016/J.SCITOTENV.2019.01.102
Abstract: The influence of wildfire on surface soil and hydrology has been widely investigated, while its impact on the karst vadose zone is still poorly understood. A moderate to severe experimental fire was conducted on a plot (10 m × 10 m) above the shallow Wildman's Cave at Wombeyan Caves, New South Wales, Australia in May 2016. Continuous s ling of water stable isotopes, inorganic geochemistry and drip rates were conducted from Dec 2014 to May 2017. After the fire, drip discharge patterns were significantly altered, which is interpreted as the result of increased preferential flows and decreased diffuse flows in the soil. Post-fire drip water δ
Persistent Positive North Atlantic Oscillation Mode Dominated the Medieval Climate Anomaly
Publisher: American Association for the Advancement of Science (AAAS)
Date: 03-04-2009
Abstract: The Medieval Climate Anomaly (MCA) was the most recent pre-industrial era warm interval of European climate, yet its driving mechanisms remain uncertain. We present here a 947-year-long multidecadal North Atlantic Oscillation (NAO) reconstruction and find a persistent positive NAO during the MCA. Supplementary reconstructions based on climate model results and proxy data indicate a clear shift to weaker NAO conditions into the Little Ice Age (LIA). Globally distributed proxy data suggest that this NAO shift is one aspect of a global MCA-LIA climate transition that probably was coupled to prevailing La Niña–like conditions lified by an intensified Atlantic meridional overturning circulation during the MCA.
Characterisation of algogenic organic matter extracted from cyanobacteria, green algae and diatoms
Publisher: Elsevier BV
Date: 07-2008
DOI: 10.1016/J.WATRES.2007.10.032
Abstract: Algogenic organic matter (AOM) can interfere with drinking water treatment processes and comprehensive characterisation of AOM will be informative with respect to treatability. This paper characterises the AOM originating from four algae species (Chlorella vulgaris, Microcystis aeruginosa, Asterionella formosa and Melosira sp.) using techniques including dissolved organic carbon (DOC), specific UV absorbance (SUVA), zeta potential, charge density, hydrophobicity, protein and carbohydrate content, molecular weight and fluorescence. All AOM was predominantly hydrophilic with a low SUVA. AOM had negative zeta potential values in the range pH 2-10. The stationary phase charge density of AOM from C. vulgaris was greatest at 3.2 meq g(-1) while that of M. aeruginosa and Melosira sp. was negligible. Lower charge density was related to higher hydrophobicity, while it was related in turn to increasing proteins >500 kDa:carbohydrate ratio. This demonstrates that AOM is of a very different character to natural organic matter (NOM).
Fluorescent properties of organic carbon in cave dripwaters: Effects of filtration, temperature and pH
Publisher: Elsevier BV
Date: 11-2010
DOI: 10.1016/J.SCITOTENV.2010.08.040
Abstract: For the first time the specific fluorescent characteristics of organic carbon (OC) in sequentially filtered cave dripwater s les have been studied and the proportions of organic carbon in each size fraction quantified. We examined the effects of pH, temperature and filtration on the fluorescent properties of OC s led from four drip points in different seasons. Dripwaters were s led from both normal (pH 7.5-8.5) and hyper-alkaline (pH 9-13) drip points in Poole's Cavern, Buxton, UK, which provides a model system for understanding the effects of pH on the chemical properties of OC. At high-pH values, charge stabilisation of OC is greatly enhanced, resulting in 10-20 times more coarse colloidal and particulate (>100 nm) organic carbon than in lower pH dripwaters indicating that destabilisation (e.g. charge shielding) of colloidal OC is an important process control on the transmission of OC in cave dripwaters at near-neutral pH. OC fluorescence in high-pH dripwaters exhibited a high degree of pH sensitivity between pH 10 and 12, consistent with substantial changes in the coordination or neighbouring environment of fluorescent acidic functional groups. Inner-filter effects (IFE) associated with the coarse colloidal and particulate fraction of OM mask the true fluorescent signal, so that size fractionation is necessary to obtain a signal which is correlated with the concentration of organic carbon. Fluorescence intensities in the s les studied were best correlated with organic carbon with a dimension <100 nm. These results have important implications for the use of fluorescence as a tracer in hydrogeological studies.
Characterization of dissolved organic matter from source to sea using fluorescence and absorbance spectroscopy
Publisher: Elsevier BV
Date: 10-2004
Spectrophotometric discrimination of river dissolved organic matter
Publisher: Wiley
Date: 10-2002
DOI: 10.1002/HYP.1097
Cave use and palaeoecology at Maludong (Red Deer Cave), Yunnan, China
Publisher: Elsevier BV
Date: 08-2016
High resolution δ18O and δ13C records from an annually laminated Scottish stalagmite and relationship with last millennium climate
Publisher: Elsevier BV
Date: 12-2011
Roles of forest bioproductivity, transpiration and fire in a nine-year record of cave dripwater chemistry from southwest Australia
Publisher: Elsevier BV
Date: 07-2016
Probabilistic analysis of fluorescence signals for monitoring dual reticulation water recycling schemes
Publisher: IWA Publishing
Date: 11-2010
DOI: 10.2166/WST.2010.504
Abstract: Improved techniques are required for the detection of inadvertent cross-connections between recycled water and potable water systems in dual reticulation schemes. The aim of this research was to assess the potential for fluorescence spectroscopy to be developed as a tool to distinguish recycled water from potable water. Weekly grab s les of recycled and potable water were obtained over 12 weeks from within an Australian dual reticulation site and analysed for fluorescence excitation-emission matrix (EEM), dissolved organic carbon (DOC), electrical conductivity (EC), and pH. Probabilistic techniques including distribution function fitting and Monte Carlo simulation were used to assess the ability to distinguish between recycled water and potable water s le pairs and the reliability of doing so. Fluorescence EEM spectroscopy was determined to be the most effective for the reliable differentiation by monitoring the protein-like fluorescence at peak T1—an excitation-emission wavelength pair of λex/em=300/350 nm. While EC could distinguish between recycled and potable water, it was shown to be less sensitive and less reliable than peak T1 fluorescence.
Unsaturated zone hydrology and cave drip discharge water response: Implications for speleothem paleoclimate record variability
Publisher: Elsevier BV
Date: 10-2015
Supplementary material to "Hydroclimate of the Last Glacial Maximum and deglaciation in southern Australia’s arid margin interpreted from speleothem records (23–15 ka)"
Publisher: Copernicus GmbH
Date: 21-12-2016
Time lapse electric resistivity tomography to portray infiltration and hydrologic flow paths from surface to cave
Publisher: Elsevier BV
Date: 02-2021
Supplementary material to SISALv3: A global speleothem stable isotope and trace element database
Publisher: Copernicus GmbH
Date: 13-09-2023
Analysis of the climate signal contained within δ18O and growth rate parameters in two Ethiopian stalagmites
Publisher: Elsevier BV
Date: 06-2007
Analysis of rainwater dissolved organic carbon compounds using fluorescence spectrophotometry
Publisher: Elsevier BV
Date: 11-2008
Lipid distribution in a subtropical southern China stalagmite as a record of soil ecosystem response to paleoclimate change
Publisher: Cambridge University Press (CUP)
Date: 07-2003
DOI: 10.1016/J.YQRES.2003.07.010
Abstract: Lipid extracts from a 61.7-cm-long subtropical stalagmite in southern China, spanning the period of ca. 10,000–21,000 yr ago as constrained by U–Th dating, were analyzed using gas chromatography–mass spectrometry. The higher plants and microorganisms in the overlying soils contribute a proportion of n -alkanes identified in the stalagmite. The occurrence of LMW (lower molecular weight) n -alkanols and n -alkan-2-ones in the stalagmite was mainly related to the soil microorganisms. We suggest that HMW (higher molecular weight) n -alkanols and n -alkan-2-ones identified in the stalagmite originate from soil organics and reflect input from contemporary vegetation. Shifts in the ratio of LMW to HMW n -alkanols or n -alkan-2-ones indicative of the variation of soil ecosystems (e.g., microbial degradation of organic matter and/or the relative abundance of soil microorganisms to higher plants) are comparable with the subtropical alkenone-SST (sea surface temperature) record of the same period. The similar trends seen in the δ 13 C data and the lipid parameters in this stalagmite imply that the overlying soil ecosystem response to climate might be responsible for the variation of δ 13 C values.
Cave drip water solutes in south-eastern Australia: Constraining sources, sinks and processes
Publisher: Elsevier BV
Date: 02-2019
DOI: 10.1016/J.SCITOTENV.2018.10.035
Abstract: Constraining sources and site-specific processes of trace elements in speleothem geochemical records is key to an informed interpretation. This paper examines a 10-year data set of drip water solutes from Harrie Wood Cave, south-eastern Australia, and identifies the processes that control their response to El Niño-Southern Oscillation events which varies the site water balance. The contributions of aerosol and bedrock end-members are quantified via hydrochemical mass balance modelling. The parent bedrock is the main source for the drip water solutes: Mg, Sr, K and trace elements (Ba, Al, V, Cr, Mn, Ni, Co, Cu, Pb and U), while atmospheric aerosol inputs also contribute significantly to drip water trace elements and Na, K and Zn. A laboratory investigation evaluating water-soluble fractions of metals in soil s les and soil enrichment factors provided a basis for understanding metal retainment and release to solution and transport from the soil zone. These results identified the role of the soil as a sink for: trace metals, Na and K, and a secondary source for Zn. Further, soil processes including: cation exchange, K-fixation, metal adsorption to colloids and the release of Zn associated with organic matter degradation further modify the chemical composition of the resultant drip waters. This research is significant for the south-eastern Australian region, as well as other sites in a karst setting with clay-rich soil. In particular these results reveal that the response of drip water chemistry to hydroclimatic forcing is non-linear, with the greatest response observed when the long-term gradient in the cumulative water balance reverses. This longer-term drip water monitoring dataset is significant because it provides the pivotal framework required to reliably identify suitable trace element proxies for interpretation in geochemical speleothem records on multi-decadal timescales.
Effects of filtration and pH perturbation on freshwater organic matter fluorescence
Publisher: Elsevier BV
Date: 05-2007
DOI: 10.1016/J.CHEMOSPHERE.2006.11.024
Abstract: Fluorescence of organic matter from six contrasting freshwaters was analysed after filtration (1.2 microm and 0.2 microm filter sizes) and pH perturbation (+/-2 pH units from ambient conditions). Two fluorophores were compared in detail: tryptophan-like fluorescence, whose filtration and pH characteristics are relatively poorly understood, and humic-like fluorescence, which is better characterised. Although there was some variability in both fluorophores, the tryptophan-like fluorescence showed the most significant decrease in fluorescence intensity between raw and 1.2 microm filter s les, and a much smaller decrease between 1.2 and 0.2 microm, demonstrating a significant source associated with particulate material as well as a significant <0.2 microm fraction. In contrast, humic-like fluorescence shows little change with filtration, suggesting that the majority of this fluorescence is associated with truly dissolved material. The pH perturbation experiments demonstrate that tryptophan-like fluorescence is less impacted by pH than with filter fraction. For humic-like fluorescence, pH effects are weak and are not as consistent as those reported in the literature for extracted humic substances. pH perturbation of the freshwaters shows a wide range of s le specific pH responses, significantly more variable than that observed in experiments using extracted humic substances and tryptophan standards, demonstrating the natural variability of freshwater dissolved organic matter.
Exploratory analysis of excitation–emission matrix fluorescence spectra with self-organizing maps—A tutorial
Publisher: Elsevier BV
Date: 2012
Sulphur variations in annually layered stalagmites using benchtop micro-XRF
Publisher: Elsevier BV
Date: 03-2022
Reconstructing hemispheric-scale climates from multiple stalagmite records
Publisher: Wiley
Date: 2006
DOI: 10.1002/JOC.1329
A soil moisture monitoring network to characterize karstic recharge and evapotranspiration at five representative sites across the globe
Publisher: Copernicus GmbH
Date: 25-02-2020
DOI: 10.5194/GI-9-11-2020
Abstract: Abstract. Karst systems are characterized by a high subsurface heterogeneity, and their complex recharge processes are difficult to characterize. Experimental methods to study karst systems mostly focus on analysing the entire aquifer. Despite their important role in recharge processes, the soil and epikarst receive limited attention, and the few available studies were performed at sites of similar latitudes. In this paper, we describe a new monitoring network that allows for the improvement of the understanding of soil and epikarst processes by including different karst systems with different land-cover types in different climate regions. Here, we present preliminary data form the network and elaborate on their potential to answer research questions about the role of soil and epikarst on karstic water flow and storage. The network measures soil moisture at multiple points and depths to understand the partitioning of rainfall into infiltration, evapotranspiration, and groundwater recharge processes. We installed soil moisture probes at five different climate regions: Puerto Rico (tropical), Spain (Mediterranean), the United Kingdom (humid oceanic), Germany (humid mountainous), and Australia (dry semi-arid). At each of the five sites, we defined two 20 m×20 m plots with different land-use types (forest and grassland). At each plot, 15 soil moisture profiles were randomly selected and probes at different depths from the topsoil to the epikarst (in total over 400 soil moisture probes) were installed. Covering the spatio-temporal variability of flow processes through a large number of profiles, our monitoring network will allow researchers to develop a new conceptual understanding of evapotranspiration and groundwater recharge processes in karst regions across different climate regions and land-use types, and this will provide the base for quantitative assessment with physically based modelling approaches in the future.
An underground drip water monitoring network to characterize rainfall recharge of groundwater at different geologies, environments, and climates across Australia
Publisher: Copernicus GmbH
Date: 19-09-2023
Simulation of Earth textures by conditional image quilting
Publisher: American Geophysical Union (AGU)
Date: 04-2014
DOI: 10.1002/2013WR015069
Changes in groundwater dissolved organic matter character in a coastal sand aquifer due to rainfall recharge
Publisher: Elsevier BV
Date: 02-2020
DOI: 10.1016/J.WATRES.2019.115201
Abstract: Dissolved organic matter (DOM) in groundwater is fundamentally important with respect to biogeochemical reactions, global carbon cycling, heavy metal transport, water treatability and potability. One source of DOM to groundwater is from the transport of organic matter from the vadose zone by rainfall recharge. Changes in precipitation patterns associated with natural climate variability and climate change are expected to alter the load and character of organic matter released from these areas, which ultimately impacts on groundwater quality and DOM treatability. In order to investigate potential changes in groundwater DOM character after rainfall recharge, we s led shallow groundwater from a coastal peat-rich sand aquifer in New South Wales, Australia, during an extended period of low precipitation (average daily precipitation rate < 1.6 mm day
Fluorescence spectroscopy as a tool for determining microbial quality in potable water applications
Publisher: Informa UK Limited
Date: 21-10-2011
DOI: 10.1080/09593330.2011.588401
Abstract: Building on previous work where fluorescence spectroscopy has been used to detect sewage in rivers, a portable LED spectrophotometer was used for the first time to establish bacterial numbers in a range of water s les. A mixed-method approach was used with standard bacteria enumeration techniques on diluted river water and sewage works final effluent using a number of diluents (Ringer's solution, tap water and potable spring water). Fluorescence from uncultured dilutions was detected at a 280 nm excitation/360 nm emission wavelength (corresponding to the region of tryptophan and indole fluorescence) and compared with bacteria numbers on the same cultured s le. Good correlations were obtained for total coliforms, E. coli and heterotrophic bacteria with the portable LED spectrophotometer (R2 = 0.78, 0.72 and 0.81 respectively). The results indicate that the portable spectrophotometer could be applied to establish the quality of drinking water in areas of poor sanitation that are subject to faecal contamination, where infrastructure failure has occurred in the supply of clean drinking water. This would be particularly useful where laboratory facilities are not at hand.
Letter to the Editor: Comment on “a test of annual resolution in stalagmites using tree rings”
Publisher: Cambridge University Press (CUP)
Date: 05-2003
What determines the calcium concentration of speleothem-forming drip waters?
Publisher: Elsevier BV
Date: 08-2016
Semi-arid zone caves: Evaporation and hydrological controls on δ18O drip water composition and implications for speleothem paleoclimate reconstructions
Publisher: Elsevier BV
Date: 2016
Ubiquitous karst hydrological control on speleothem oxygen isotope variability in a global study
Publisher: Springer Science and Business Media LLC
Date: 15-02-2022
DOI: 10.1038/S43247-022-00347-3
Abstract: Speleothem oxygen isotopic (δ 18 O) records are used to reconstruct past hydroclimate yet records from the same cave do not always replicate. We use a global database of speleothem δ 18 O to quantify the replicability of records to show that disagreement is common worldwide, occurs across timescales and is unrelated to climate, depth or lithology. Our global analysis demonstrates that within-cave differences in mean speleothem δ 18 O values are consistent with those of dripwater, supporting a ubiquitous influence of flowpaths. We present a case study of four new stalagmite records from Golgotha Cave, southwest Australia, where the isotopic differences between them are informed by cave monitoring. It is demonstrated that karst hydrology is a major driver of within-cave speleothem and dripwater δ 18 O variability, primarily due to the influence of fractures on flowpaths. Applying our understanding of water movement through fractures assists in quantitative reconstruction of past climate variability from speleothem δ 18 O records.
Carbon isotopic characterisation of dissolved organic matter during water treatment
Publisher: Elsevier BV
Date: 2014
DOI: 10.1016/J.WATRES.2013.09.025
Abstract: Water treatment is a series of physio-chemical processes to aid organic matter (OM) removal, which helps to minimise the formation of potentially carcinogenic disinfection by-products and microbial regrowth. Changes in OM character through the treatment processes can provide insight into the treatment efficiency, but radiogenic isotopic characterisation techniques have yet to be applied. Here, we show for the first time that analysis of (13)C and (14)C of dissolved organic carbon (DOC) effectively characterises dissolved OM through a water treatment works. At the sites investigated: post-clarification, DOC becomes isotopically lighter, due to an increased proportion of relatively hydrophilic DOC. Filtration adds 'old' (14)C-DOC from abrasion of the filter media, whilst the use of activated carbon adds 'young' (14)C-DOC, most likely from the presence of biofilms. Overall, carbon isotopes provide clear evidence for the first time that new sources of organic carbon are added within the treatment processes, and that treated water is isotopically lighter and typically younger in (14)C-DOC age than untreated water. We anticipate our findings will precipitate real-time monitoring of treatment performance using stable carbon isotopes, with associated improvements in energy and carbon footprint (e.g. isotopic analysis used as triggers for filter washing and activated carbon regeneration) and public health benefits resulting from improved carbon removal.
Late Quaternary speleothem pollen in the British Isles
Publisher: Wiley
Date: 06-09-2008
DOI: 10.1002/JQS.1121
The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems
Publisher: Copernicus GmbH
Date: 14-09-0030
DOI: 10.5194/ESSD-10-1687-2018
Abstract: Abstract. Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-s le” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for in idual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (δ18O, δ13C) measurements are referenced by distance from the top or bottom of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information on the full range of measurements carried out on each speleothem and information on the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data. The compiled data are available at 0.17864/1947.147.
Portable LED fluorescence instrumentation for the rapid assessment of potable water quality
Publisher: Elsevier BV
Date: 08-2015
DOI: 10.1016/J.SCITOTENV.2015.04.050
Abstract: Characterising the organic and microbial matrix of water are key issues in ensuring a safe potable water supply. Current techniques only confirm water quality retrospectively via laboratory analysis of discrete s les. Whilst such analysis is required for regulatory purposes, it would be highly beneficial to monitor water quality in-situ in real time, enabling rapid water quality assessment and facilitating proactive management of water supply systems. A novel LED-based instrument, detecting fluorescence peaks C and T (surrogates for organic and microbial matter, respectively), was constructed and performance assessed. Results from over 200 s les taken from source waters through to customer tap from three UK water companies are presented. Excellent correlation was observed between the new device and a research grade spectrophotometer (r(2)=0.98 and 0.77 for peak C and peak T respectively), demonstrating the potential of providing a low cost, portable alternative fluorimeter. The peak C/TOC correlation was very good (r(2)=0.75) at low TOC levels found in drinking water. However, correlations between peak T and regulatory measures of microbial matter (2 day/3 day heterotrophic plate counts (HPC), E. coli, and total coliforms) were poor, due to the specific nature of these regulatory measures and the general measure of peak T. A more promising correlation was obtained between peak T and total bacteria using flow cytometry. Assessment of the fluorescence of four in idual bacteria isolated from drinking water was also considered and excellent correlations found with peak T (Sphingobium sp. (r(2)=0.83) Methylobacterium sp. (r(2)=1.0) Rhodococcus sp. (r(2)=0.86) Xenophilus sp. (r(2)=0.96)). It is notable that each of the bacteria studied exhibited different levels of fluorescence as a function of their number. The scope for LED based instrumentation for in-situ, real time assessment of the organic and microbial matrix of potable water is clearly demonstrated.
Characterisation of dissolved organic matter to optimise powdered activated carbon and clarification removal efficiency
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0EW00149J
Abstract: Removal of dissolved organic matter fractions via three different treatment processes.
10th International Conference on Environmental Remediation and Radioactive Waste Management (ICEM05)
Publisher: IOP Publishing
Date: 26-05-2006
Caves provide early warning of unprecedented decrease in rainfall recharge of groundwater
Publisher: Research Square Platform LLC
Date: 02-05-2022
DOI: 10.21203/RS.3.RS-1556439/V1
Abstract: Billions of people worldwide rely on groundwater. As rainfall in many regions in the future is projected to decrease, it is critical to understand the impacts of climate change on groundwater recharge. In this study, five caves record a consistent response to a sustained decrease in rainfall across southwest Australia that began in the late 1960s, characterised by a pronounced increase or ’uptick’ in dripwater and speleothem oxygen isotopic composition (δ18O). It is demonstrated that the uptick is in response to the shallow karst aquifers becoming disconnected from recharge due to regional drying. Our findings imply that rainfall recharge to groundwater across this region is no longer reliably occurring. Examination of the longer speleothem record shows that this is unprecedented over at least the last 800 years. A global network of cave dripwater monitoring would serve as an early warning of reduced groundwater recharge elsewhere, while evidence for upticks in speleothem paleoclimate records would provide a longer-term context to evaluate if current groundwater recharge changes are outside the range of natural variability. This study also validates speleothems as recorders of past hydroclimate via lification of the δ18O signal by karst hydrology highlighting that speleothem δ18O are records of recharge, rather than a direct proxy for rainfall.
Protein-like fluorescence intensity as a possible tool for determining river water quality
Publisher: Wiley
Date: 11-10-2014
DOI: 10.1002/HYP.5597
WlCount: Geological lamination detection and counting using an image analysis approach
Publisher: California Digital Library (CDL)
Date: 31-01-2022
DOI: 10.31223/X5KS6W
Abstract: The manual identification and count of laminae in layered textures is a common practice in the study of geological records, which can be time consuming and carry large uncertainty for dense or disturbed lamina textures. We present here a novel image analysis approach to detect and count laminae in geoscientific imagery, called WlCount. Based on Dynamic Time Warping and Wavelet analysis, WlCount firstly aligns persistent vertical elements to increase the continuity of the lamina structure. Then, using a graphical interface, the user extracts the most significant signal frequencies and allows the automatic count of the laminae. The software, tested on a series of stalagmite cut images showing different types of laminations and a tree-ring image, provides an estimation of the laminae detection and count comparable to the manual one. WlCount presents as a useful open-source tool to help geoscientists, sensibly speeding up the lamination count process.
Climatic influences on the offset between d18O of cave drip waters and precipitation inferred from global monitoring data
Publisher: California Digital Library (CDL)
Date: 28-06-2023
Abstract: We present a meta-analysis of data from 22 caves and 96 drip sites from 4 continents where both the cave drip water d18O and the weighted mean d18O of precipitation have been measured. Drip water d18O is similar to the weighted mean d18O of precipitation (within ± 0.3 ‰) for sites where mean annual temperature (MAT) is less than 15 °C (85% of drips where MAT & 15 °C) and an aridity index (annual precipitation (P) / annual potential evapotranspiration (PET)) is greater than 0.65 (74% of drips at sites where P/PET & 0.65). In contrast, at warmer locations with increased water deficit, drip water d18O deviates from the weighed mean precipitation d18O by +3 ‰ and -1.5 ‰. We argue that this is due to evaporation in the soil and shallow vadose zone (thereby increasing drip water d18O) and lower water storage in the vadose zone, leading to relatively less mixing (thereby increasing the range in drip water d18O to more closely reflect recharge water d18O). Speleothems that have formed close to isotopic equilibrium are likely to have an oxygen isotope composition that contains a mixed signal of cave air temperature and precipitation d18O only in cool and temperate regions (T & 15 °C), or very wet climates where P/PET & & 0.65. In contrast, in warmer and drier environments, speleothems which have formed close to equilibrium will have d18O that reflects cave air temperature and a seasonal bias toward the d18O composition of rain in periods of high recharge, as well as the extent of evaporative fractionation of stored karst water.
Is global warming affecting cave temperatures? Experimental and model data from a paradigmatic case study
Publisher: Springer Science and Business Media LLC
Date: 28-06-2014
Changes in freshwater organic matter fluorescence intensity with freezing/thawing and dehydration/rehydration
Publisher: American Geophysical Union (AGU)
Date: 09-2020
DOI: 10.1029/2008JG000915
Thermal quenching of fluorescence of freshwater, planktonic bacteria
Publisher: Elsevier BV
Date: 04-2006
Organic matter fluorescence in municipal water recycling schemes: Toward a unified PARAFAC model
Publisher: American Chemical Society (ACS)
Date: 03-2011
DOI: 10.1021/ES103015E
Abstract: Organic matter (OM) is a ubiquitous constituent of natural waters quantifiable at very low levels using fluorescence spectroscopy. This technique has recognized potential in a range of applications where the ability to monitor water quality in real time is desirable, such as in water treatment systems. This study used PARAFAC to characterize a large (n=1479) and erse excitation emission matrix (EEM) data set from six recycled water treatment plants in Australia, for which sources of variability included geography, season, treatment processes, pH and fluorometer settings. Five components were identified independently in four or more plants, none of which were generated during the treatment process nor were typically entirely removed. PARAFAC scores could be obtained from EEMs by simple regression. The results have important implications for online monitoring of OM fluorescence in treatment plants, affecting choices regarding experimental design, instrumentation and the optimal wavelengths for tracking fluorescent organic matter through the treatment process. While the multimodel comparisons provide a compelling demonstration of PARAFAC's ability to distill chemical information from EEMs, deficiencies identified through this process have broad implications for interpreting and reusing (D)OM-PARAFAC models.
Stable isotopic composition of raw and treated water
Publisher: Thomas Telford Ltd.
Date: 07-2014
Abstract: To date, the δ 18 O and δ 2 H stable isotopic composition of freshwaters has received little attention compared to stable isotopes in precipitation. Specifically, studies characterising the stable isotopic variability of surface waters on regional and local scales are limited. Here, the δ 18 O and δ 2 H stable isotopic compositions of raw and partially treated waters from 16 UK water treatment works are examined. The water treatment works abstract surface waters from a range of catchments (upland versus lowland and semi-natural versus anthropogenically impacted). The investigation of stable isotope composition and deuterium excess (d-excess) revealed a high degree of spatial and temporal variability. Compared to rainfall, the spatial and temporal variability of surface water is more complex and catchment-dependent. Multiple linear regression analysis identified moderately strong relationships between catchment controls (altitude, mean rainfall, base flow index, aquifer permeability, location) and δ 2 H, δ 18 O and d-excess of raw and partially treated waters. Results suggest that catchment controls explain 60% (δ 2 H), 66% (δ 18 O) and 74% (d-excess) of the variation in isotopic composition of raw water. Results also indicate that catchment permeability has a stronger influence on surface waters isotopic composition than altitude, latitude or rainfall effects. The potential benefits from the use of isotopic composition data in the water supply are discussed.
Distinguishing stage 1 and 2 reverse osmosis permeates using fluorescence spectroscopy
Publisher: IWA Publishing
Date: 10-2009
DOI: 10.2166/WST.2009.515
Abstract: Fluorescence excitation-emission matrix (EEM) spectroscopy was used to distinguish between two stages of reverse osmosis (RO) permeates as the first step towards investigating the potential application of fluorescence as a monitoring tool for membrane performance. The signal response of several fluorescence peaks present in Stage 1 and Stage 2 RO permeates of an advanced water treatment plant were compared. The humic-like fluorescence region was found to have the largest percentage difference between stages and therefore was the most appropriate for enabling differentiation. Increases in humic-like fluorescence did not correlate with increases in conductivity or dissolved organic carbon measurements. This suggests that fluorescence is a more selective and sensitive method for monitoring the organic composition of RO permeates than established methods. Fluorescence is therefore a promising tool for improved water quality monitoring of RO permeates.
A high-resolution multi-proxy stalagmite record from Mechara, Southeastern Ethiopia: palaeohydrological implications for speleothem palaeoclimate reconstruction
Publisher: Wiley
Date: 2007
DOI: 10.1002/JQS.1013
Dissolved and total organic and inorganic carbon in some British rivers
Publisher: Wiley
Date: 14-11-2008
Detecting river pollution using fluorescence spectrophotometry: case studies from the Ouseburn, NE England
Publisher: Elsevier BV
Date: 07-2003
DOI: 10.1016/S0269-7491(02)00408-6
Abstract: Recent advances in fluorescence spectrophotometry enable the analysis of river dissolved organic matter. We investigate the potential of detecting sewage pollution in a small, urbanised catchment. Downstream s ling highlighted a summer maximum in tryptophan fluorescence intensity during low flow. No correlation is observed between ammonia and tryptophan fluorescence intensity. In contrast, two sewage related point-pollution events had both high tryptophan fluorescence intensity and ammonia, suggesting that the summer tryptophan increase does not original from foul sewage. Sewage inputs to the river were therefore monitored at summer base flow. This demonstrated that > 10% of the rivers' discharge is provided by sewerage inputs and that these inputs could be grouped by their fluorescence and ammonia properties: (1) 'clean' storm waters with low ammonia and tryptophan intensity (2) 'grey' waters with high tryptophan intensity and low ammonia concentration, and (3) 'foul' waters with high tryptophan intensity and ammonia concentration. All three types of sewerage input occurred irrespective of flow conditions,suggesting that sewerage cross connections are occurring.
An initial investigation into the organic matter biogeochemistry of the Congo River
Publisher: Elsevier BV
Date: 05-2012
A method to anchor floating chronologies in annually laminated speleothems with U–Th dates
Publisher: Elsevier BV
Date: 12-2012
Changes in global groundwater organic carbon driven by climate change and urbanization
Publisher: California Digital Library (CDL)
Date: 15-11-2018
Modelling the 14C bomb-pulse in young speleothems using a soil carbon continuum model
Publisher: Elsevier BV
Date: 09-2019
How water isotopes (18O, 2H, 3H) within an island freshwater lens respond to changes in rainfall
Publisher: Elsevier BV
Date: 03-2020
DOI: 10.1016/J.WATRES.2019.115301
Abstract: Coastal aquifers provide an important source of water globally. Understanding how groundwater responds to changes in rainfall recharge is important for sustainable development. To this end, we investigate how water isotopes (
Photochemical degradation of dissolved organic matter and dissolved lignin phenols from the Congo River
Publisher: American Geophysical Union (AGU)
Date: 22-08-2009
DOI: 10.1029/2009JG000968
Utilising seasonal variations in hydrogeochemistry and excitation-emission fluorescence to develop a conceptual groundwater flow model with implications for subsidence hazards: an example from Co. Dur
Publisher: Springer Science and Business Media LLC
Date: 18-06-2005
Related Organisations
University Of Birmingham
Location: United Kingdom of Great Britain and Northern Ireland
University Of Bristol
Location: United Kingdom of Great Britain and Northern Ireland
Newcastle University
Location: United Kingdom of Great Britain and Northern Ireland
University Of Exeter
Location: United Kingdom of Great Britain and Northern Ireland
Related Funding Activities
Last Millennium Climate Reconstruction In Ethiopia Using Multiple Stalagmite Parameters
Start Date: 2009
End Date: 2012
Funder: Natural Environment Research Council
View Funded ActivityDoctoral Training Grant (DTG) To Provide Funding For 2 PhD Studentships
Start Date: 2009
End Date: 2011
Funder: Natural Environment Research Council
View Funded ActivityA Mass Spectrometer To Analyse Carbonate Isotope Records Of Australia's Climate, Soil And Groundwater History
Start Date: 2011
End Date: 2011
Funder: Australian Research Council
View Funded ActivityDoctoral Training Grant (DTG) To Provide Funding For 2 PhD Studentships
Start Date: 2009
End Date: 2013
Funder: Natural Environment Research Council
View Funded ActivityMonitoring Organic Matter In Drinking Water Systems Using Fluorescence Spectroscopy: Improved Early Warning, Process Optimisation And Water Quality
Start Date: 2010
End Date: 2013
Funder: Australian Research Council
View Funded ActivityA Coupled High Temperature Elemental Analyser - Gas Chromatograph - Mass Spectrometer For Climate, Water And Ecological Research
Start Date: 2014
End Date: 2014
Funder: Australian Research Council
View Funded ActivityFluorescence As A Tool For Sensitive Detection Of Failures In Recycled Water Treatment And Distribution Systems
Start Date: 2007
End Date: 2010
Funder: Australian Research Council
View Funded ActivityAn Australian Fluid-inclusion Facility For Climate-change Science
Start Date: 2012
End Date: 2012
Funder: Australian Research Council
View Funded ActivityDoctoral Training Grant (DTG) To Provide Funding For 6 PhD Studentships
Start Date: 2009
End Date: 2011
Funder: Natural Environment Research Council
View Funded ActivityGroundwater Organic Matter
Start Date: 2016
End Date: 2018
Funder: Australian Research Council
View Funded ActivityGlobal Assessment Of Water Stress In Karst Regions In A Changing World
Start Date: 2017
End Date: End date not available
Funder: German Research Foundation
View Funded ActivityTo What Extent Does Fire Affect Karst Processes? Burning Questions For Fire Management
Start Date: 2013
End Date: 2015
Funder: Australian Research Council
View Funded ActivityUnlocking The Secrets Of The Groundwater Cycle Using Silicon And Lithium Isotopes
Start Date: 2015
End Date: 2016
Funder: Australian Research Council
View Funded ActivitySource - Receptor Analysis Of Lignin And Lipid Macromolecules In Karst To Quantify Stalagmite Biomarker Proxies Of Vegetation And Temperature Change
Start Date: 2011
End Date: 2013
Funder: Australian Research Council
View Funded ActivityWater Quality Measurement In Regions Of Poor Sanitation
Start Date: 2009
End Date: 2011
Funder: Engineering and Physical Sciences Research Council
View Funded ActivityPrecipitation-groundwater Interactions Over Eastern Australia: Climate Change Impacts At Multiple Scales
Start Date: 2010
End Date: 2013
Funder: Australian Research Council
View Funded ActivityProject LE140100023
Start Date: 2014
End Date: 2014
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP110102124
Start Date: 2011
End Date: 05-2015
Amount: $320,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP100200259
Start Date: 04-2011
End Date: 03-2014
Amount: $152,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP150100144
Start Date: 05-2016
End Date: 03-2019
Amount: $138,091.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP160101379
Start Date: 2016
End Date: 12-2019
Amount: $473,300.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE110100045
Start Date: 2011
End Date: 01-2012
Amount: $370,000.00
Funder: Australian Research Council
View Funded ActivitySuper Science Fellowships - Grant ID: FS100100054
Start Date: 10-2010
End Date: 04-2014
Amount: $835,200.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE120100180
Start Date: 01-2012
End Date: 06-2014
Amount: $150,000.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP200100203
Start Date: 07-2020
End Date: 07-2024
Amount: $472,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE220100125
Start Date: 2022
End Date: 12-2023
Amount: $158,845.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE140100088
Start Date: 2014
End Date: 12-2014
Amount: $150,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP0776347
Start Date: 02-2008
End Date: 01-2012
Amount: $380,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE140100023
Start Date: 2014
End Date: 12-2014
Amount: $360,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP130100177
Start Date: 07-2014
End Date: 06-2017
Amount: $193,150.00
Funder: Australian Research Council
View Funded ActivitySpecial Research Initiatives - Grant ID: NCGRT
Start Date: 07-2009
End Date: 12-2015
Amount: $14,999,996.00
Funder: Australian Research Council
View Funded Activity