ORCID Profile
0000-0002-9873-6846
Current Organisation
Charles Darwin University
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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)
Surfacewater Hydrology | Ecosystem Function | Stochastic Analysis and Modelling | Environmental Science and Management | Ecological Applications | Social and Cultural Geography | Environmental Chemistry (incl. Atmospheric Chemistry) | Physical Geography and Environmental Geoscience | Natural Resource Management | Aboriginal and Torres Strait Islander Education
ANZSRC Socio-Economic Objective (SEO)
Ecosystem Assessment and Management of Fresh, Ground and Surface Water Environments | Ecosystem Assessment and Management at Regional or Larger Scales | Physical and Chemical Conditions of Water in Fresh, Ground and Surface Water Environments (excl. Urban and Industrial Use) | Control of Pests, Diseases and Exotic Species at Regional or Larger Scales | Education and Training Systems Policies and Development |
Related Links
Publications
Deuterium depletion in xylem water and soil isotopic effects complicate the assessment of riparian tree water sources in the seasonal tropics
Publisher: Wiley
Date: 16-12-2021
DOI: 10.1002/ECO.2383
Abstract: Riparian trees located in seasonally dry environments may be reliant on groundwater supplies, but the prevalence and magnitude of groundwater uptake is often unclear. Using soil water matric potential and water stable isotopes, we examined the relative contributions of soil water and groundwater to the dry season water uptake of five riparian tree species along an intermittent river of tropical northern Australia. Because xylem water was depleted in deuterium relative to source water (average offset −14.0‰), we numerically removed this offset and assessed the effect of the correction on mixing model results. We also estimated the isotopic composition of unbound soil water (i.e., the portion of soil water not tightly bound to soil particles) from bulk soil water data by using an empirical formulation from the literature and tested whether considering unbound soil water as a source would affect our results. Despite the hot and dry surface environment, we found that soil moisture was available for trees at relatively shallow (~0.7–1.5 m) depths. When unbound soil water and corrected xylem water data were considered, most tree species used a combination of this soil moisture source and groundwater from the capillary fringe. However, not correcting for isotopic effects resulted in large underestimations of the groundwater contributions to tree water uptake. Our findings suggest that ignoring soil isotopic effects and deuterium depletion in xylem water may reduce the validity of source water partitioning assessments. Further research is needed on the likely causes for deuterium depletion in xylem water.
Controls on spatial variability in mean concentrations and export patterns of river chemistry across the Australian continent
Publisher: Wiley
Date: 22-03-2022
Sub-daily variability of suspended sediment fluxes in small mountainous catchments &ndash implications for community-based river monitoring
Publisher: Copernicus GmbH
Date: 02-03-2011
Abstract: Abstract. Accurate estimates of suspended sediment yields depend on effective monitoring strategies. In mountainous environments undergoing intense seasonal precipitation, the implementation of such monitoring programs relies primarily on a rigorous study of the temporal variability of fine sediment transport. This investigation focuses on seasonal and short-term variability in suspended sediment flux in a subhumid region of the Mexican Volcanic Belt. Intensive monitoring was conducted during one year in four contrasting catchments (3 to 630 km2). Analyses revealed significant temporal variability in suspended sediment export over various time scales, with between 63 and 97% of the annual load exported in as little as 2% of the time. Statistical techniques were used to evaluate the s ling frequency required to get reliable estimates of annual sediment yield at the four sites. A bi-daily s ling scheme would be required at the outlet of the 630 km2 catchment, whereas in the three smaller catchments (3–12 km2), accurate estimates would inevitably require hourly monitoring. At the larger catchment scale, analysis of the sub-daily variability of fine sediment fluxes showed that the frequency of s ling could be lowered by up to 100% (i.e. from bi-daily to daily) if a specific and regular s ling time in the day was considered. In contrast, conducting a similar s ling strategy at the three smaller catchments could lead to serious misinterpretation (i.e. up to 1000% error). Our findings emphasise the importance of an analysis of the sub-daily variability of sediment fluxes in mountainous catchments. Characterising this variability may offer useful insights for improving the effectiveness of community-based monitoring strategies in rural areas of developing countries. In regions where historical records based on discrete s ling are available, it may also help assessing the quality of past flux estimates. Finally, the study confirms the global necessity of acquiring more high frequency data in small mountainous catchments, especially in poorly gauged areas.
Hydrological processes in tropical Australia: Historical perspective and the need for a catchment observatory network to address future development
Publisher: Elsevier BV
Date: 10-2022
Net landscape carbon balance of a tropical savanna: Relative importance of fire and aquatic export in offsetting terrestrial production
Publisher: Wiley
Date: 13-08-2020
DOI: 10.1111/GCB.15287
Sediment dynamics during the rainy season in tropical highland catchments of central Mexico using fallout radionuclides
Publisher: Elsevier BV
Date: 12-2010
Seasonal and spatial variations in rare earth elements to identify inter-aquifer linkages and recharge processes in an Australian catchment
Publisher: Elsevier BV
Date: 03-2015
Controlling feral ruminants to reduce greenhouse gas emissions: a case study of buffalo in northern Australia
Publisher: CSIRO Publishing
Date: 2023
DOI: 10.1071/WR22134
Substantial decrease in CO2 emissions from Chinese inland waters due to global change
Publisher: Springer Science and Business Media LLC
Date: 19-03-2021
DOI: 10.1038/S41467-021-21926-6
Abstract: Carbon dioxide (CO 2 ) evasion from inland waters is an important component of the global carbon cycle. However, it remains unknown how global change affects CO 2 emissions over longer time scales. Here, we present seasonal and annual fluxes of CO 2 emissions from streams, rivers, lakes, and reservoirs throughout China and quantify their changes over the past three decades. We found that the CO 2 emissions declined from 138 ± 31 Tg C yr −1 in the 1980s to 98 ± 19 Tg C yr −1 in the 2010s. Our results suggest that this unexpected decrease was driven by a combination of environmental alterations, including massive conversion of free-flowing rivers to reservoirs and widespread implementation of reforestation programs. Meanwhile, we found increasing CO 2 emissions from the Tibetan Plateau inland waters, likely attributable to increased terrestrial deliveries of organic carbon and expanded surface area due to climate change. We suggest that the CO 2 emissions from Chinese inland waters have greatly offset the terrestrial carbon sink and are therefore a key component of China’s carbon budget.
Preface special issue: “Processes and patterns in tropical hydrology”
Publisher: Wiley
Date: 07-2023
DOI: 10.1002/HYP.14931
The use of regional and alluvial groundwater by riparian trees in the wet-dry tropics of northern Australia
Publisher: Wiley
Date: 05-2021
DOI: 10.1002/HYP.14180
Abstract: Riparian trees play a critical role in the ecological function of rivers, yet are threatened by anthropogenic change to the hydrological cycle. Identifying the sources of water used by riparian trees can inform sustainable water policy. We used isotopic analysis complemented by measurements of plant water relations to assess water sources for riparian trees at two sites with contrasting hydrogeological processes one with an alluvial aquifer overlaying an aquitard, and one where fault‐induced preferential pathways in the aquitard allowed the flow of deeper, older groundwater from a regional aquifer to the alluvium. At both sites, plant water potential, stomatal conductance, and plant water isotope composition in the xylem sap of riparian trees were collected from two landscape positions, the riverbank and floodplain. We used a Bayesian mixing model (MixSIAR) to assess differences in the proportion of water sources for sites and landscape positions. We found that xylem water isotope values differed between the two sites in line with their hydrogeological characteristics, with trees at the regional aquifer site using water sourced from the regional groundwater and trees at the site with only an alluvial aquifer present using a mixture of water sources, with no dominant source identified. Higher plant predawn water potential values at the regional site indicated greater water availability and support the inference that plants were using more groundwater at the regional site compared to the alluvial site. Trees closer to the river had higher isotope values, indicative of surficial water sources i.e. shallow soil water and river water. Our findings show that the water sources used by riparian trees reflect local hydrogeology and resource availability. Water managers should identify and protect plant water sources to ensure maintenance of riparian trees.
Global carbon dioxide efflux from rivers enhanced by high nocturnal emissions
Publisher: Springer Science and Business Media LLC
Date: 15-04-2021
Land transformation in tropical savannas preferentially decomposes newly added biomass, whether C3 or C4 derived
Publisher: Wiley
Date: 28-07-2020
DOI: 10.1002/EAP.2192
Abstract: As tropical savannas are undergoing rapid conversion to other land uses, native C 3 ‐C 4 vegetation mixtures are often transformed to C 3 ‐ or C 4 ‐dominant systems, resulting in poorly understood changes to the soil carbon (C) cycle. Conventional models of the soil C cycle are based on assumptions that more labile components of the heterogenous soil organic C (SOC) pool decompose at faster rates. Meanwhile, previous work has suggested that the C 4 ‐derived component of SOC is more labile than C 3 ‐derived SOC. Here we report on long‐term (18 months) soil incubations from native and transformed tropical savannas of northern Australia. We test the hypothesis that, regardless of the type of land conversion, the C 4 component of SOC will be preferentially decomposed. We measured changes in the SOC and pyrogenic carbon (PyC) pools, as well as the carbon isotope composition of SOC, PyC and respired CO 2 , from 63 soil cores collected intact from different land use change scenarios. Our results show that land use change had no consistent effect on the size of the SOC pool, but strong effects on SOC decomposition rates, with slower decomposition rates at C 4 ‐invaded sites. While we confirm that native savanna soils preferentially decomposed C 4 ‐derived SOC, we also show that transformed savanna soils preferentially decomposed the newly added pool of labile SOC, regardless of whether it was C 4 ‐derived (grass) or C 3 ‐derived (forestry) biomass. Furthermore, we provide evidence that in these fire‐prone landscapes, the nature of the PyC pool can shed light on past vegetation composition: while the PyC pool in C 4 ‐dominant sites was mainly derived from C 3 biomass, PyC in C3‐dominant sites and native savannas was mainly derived from C 4 biomass. We develop a framework to systematically assess the effects of recent land use change vs. prior vegetation composition.
Baseflow control on sediment flux connectivity: Insights from a nested catchment study in Central Mexico
Publisher: Elsevier BV
Date: 10-2011
Time series of tritium, stable isotopes and chloride reveal short-term variations in groundwater contribution to a stream
Publisher: Copernicus GmbH
Date: 18-01-2016
Abstract: Abstract. A major limitation to the assessment of catchment transit time (TT) stems from the use of stable isotopes or chloride as hydrological tracers, because these tracers are blind to older contributions. Yet, accurately capturing the TT of the old water fraction is essential, as is the assessment of its temporal variations under non-stationary catchment dynamics. In this study we used lumped convolution models to examine time series of tritium, stable isotopes and chloride in rainfall, streamwater and groundwater of a catchment located in subtropical Australia. Our objectives were to determine the different contributions to streamflow and their variations over time, and to understand the relationship between catchment TT and groundwater residence time. Stable isotopes and chloride provided consistent estimates of TT in the upstream part of the catchment. A young component to streamflow was identified that was partitioned into quickflow (mean TT ≈ 2 weeks) and discharge from the fractured igneous rocks forming the headwaters (mean TT ≈ 0.3 years). The use of tritium was beneficial for determining an older contribution to streamflow in the downstream area. The best fits between measured and modelled tritium activities were obtained for a mean TT of 16–25 years for this older groundwater component. This was significantly lower than the residence time calculated for groundwater in the alluvial aquifer feeding the stream downstream ( ≈ 76–102 years), emphasising the fact that water exiting the catchment and water stored in it had distinctive age distributions. When simulations were run separately on each tritium streamwater s le, the TT of old water fraction varied substantially over time, with values averaging 17 ± 6 years at low flow and 38 ± 15 years after major recharge events. This counterintuitive result was interpreted as the flushing out of deeper, older waters shortly after recharge by the resulting pressure wave propagation. Overall, this study shows the usefulness of collecting tritium data in streamwater to document short-term variations in the older component of the TT distribution. Our results also shed light on the complex relationships between stored water and water in transit, which are highly non-linear and remain poorly understood.
Correlation and spectral analyses to assess the response of a shallow aquifer to low and high frequency rainfall fluctuations
Publisher: Elsevier BV
Date: 08-2015
Cultural Competence of Australian Dental Students
Publisher: Research Square Platform LLC
Date: 20-08-2020
DOI: 10.21203/RS.3.RS-54665/V1
Abstract: Background: Australia possesses a highly multicultural demographic, and thus dental practitioners are likely to encounter culturally and linguistically erse in iduals regularly. It is important for dental practitioners to be culturally competent, however, cultural competency education is highly variable in the curricula of dentistry and oral health courses in Australia, and research is largely limited to dentistry students. This study aims to investigate and compare perceived attitudes, beliefs and practices of cultural competence amongst first and final year Doctor of Dental Surgery (DDS) and Bachelor of Oral Health (BOH) students at the University of Melbourne Dental School. Methods: Following ethics approval, anonymous questionnaires were completed by 213 participants. The questionnaire was adapted from Schwarz’s Healthcare Provider Cultural Competence Instrument (HPCCI) and consisted of five scales. Data was analysed using SPSS V 24.0 software. Results: A total of 213 students participated in this study (response rate = 88%) The majority of participants were female (n=114, 53.5%) and the mean age of 23.5 years (range 18 - 40). The majority of participants were Australian born (n=110) with 74.6 percent (n=159) first generation Australians. Participants who identified as Australian represented 35.7 percent (n=76) with 66.1 percent (n=141) identified as partly Australian. Multivariate analysis indicated that, after controlling for other independent variables in the model, those who had the highest cultural competence score were female, who self-identify as “Australian”, who were in the final year. Furthermore, those who were in the final BOH year scored significatively higher than final year DDS students. Conclusion: The findings of this study suggest that there is a significant difference in students self-reported cultural competence at different stages of their education. This may be attributed to differences in cultural competence education, scope of practice and the type of patient encounters that students may experience. Future research should involve follow up to create longitudinal data, as well as research at other dental schools in Australia and overseas.
Drivers of erosion and suspended sediment transport in three headwater catchments of the Mexican Central Highlands
Publisher: Elsevier BV
Date: 11-2010
Hydrochemical processes in a shallow coal seam gas aquifer and its overlying stream–alluvial system: implications for recharge and inter-aquifer connectivity
Publisher: Elsevier BV
Date: 10-2015
CO2 evasion along streams driven by groundwater inputs and geomorphic controls
Publisher: Springer Science and Business Media LLC
Date: 29-10-2018
Tracer‐Aided Modeling in the Low‐Relief, Wet‐Dry Tropics Suggests Water Ages and DOC Export Are Driven by Seasonal Wetlands and Deep Groundwater
Publisher: American Geophysical Union (AGU)
Date: 04-2020
DOI: 10.1029/2019WR026175
Abstract: Our understanding of how wet‐dry tropical catchments process water and solutes remains limited. In this study, we attempt to gain understanding of water and dissolved organic carbon (DOC) transport, storage, and mixing in a 126 km 2 catchment of northern Australia. We developed a coupled, tracer‐aided, conceptual rainfall‐runoff model (SAVTAM) that simultaneously calculates water, isotope, and DOC‐based processes at a daily time step. The semidistributed model can account for the marked hydrological distinction between savanna woodlands and adjacent seasonal wetlands. Using the calibrated model, we tracked the fluxes and derived the age of water in fluxes and storages. Model output matched the seasonal variability, controlled by seasonal rainfall, which switched on and off water and carbon flow pathways from the savanna to seasonal wetlands and ultimately to the perennial river. Such hydrological connectivity is modulated by the karst aquifer system that continuously contributes older waters (decades to century old) to maintain relatively stable and older streamflow during the dry season (average stream water age = 9.7 to 16.2 years). Such older waters occur despite a rapid, monsoon‐driven streamflow response. The DOC fluxes were largely sourced from the wetland and riparian forest that transported DOC in the order of 1.9 t C km −2 year −1 to the stream, which was on average 90% of the total simulated DOC exports of 2 t C·km −2 ·year −1 . We conclude that coupled simulation of water and biogeochemistry is necessary to generate a more complete picture of catchment functioning, particularly in the tropics.
Towards prediction of suspended sediment yield from peak discharge in small erodible mountainous catchments (0.45–22km2) of France, Mexico and Spain
Publisher: Elsevier BV
Date: 08-2012
Sources and drivers of contamination along an urban tropical river (Ciliwung, Indonesia): Insights from microbial DNA, isotopes and water chemistry
Publisher: Elsevier BV
Date: 09-2019
DOI: 10.1016/J.SCITOTENV.2019.05.189
Abstract: Wastewater treatment infrastructure is lacking in many developing countries, often resulting in high loads of contaminants discharged to urban rivers. In these countries, targeted pollution mitigation requires an understanding of where, how and when contaminants enter water bodies. Here we report on contamination of the Ciliwung River, a dynamic, tropical system flowing through the Jakarta metropolitan area (Indonesia). We measured a set of isotopic, chemical and microbial tracers in representative water and contamination sources, as well as longitudinally within the river, to assess the spatial and temporal variations in contaminant levels in and pathways to the river. In the dry season, we observed a tight coupling between locally recharged groundwater sources and the river, whereas in the wet season, one single water source originating from the fractured headwaters predominantly contributed to river flow. Yet, the flushing of upstream waters in the wet season did not always lead to the dilution of contaminants downstream. We delineated several contamination hotspots along the river, particularly active during the wet season due to higher hydrological connectivity between sources and the river. These hotspots may originate from septic tank leakage, as supported by metal ratios and dominant microbial communities, although we could not rule out other potential sources such as urban runoff or sediment resuspension. Bayesian source tracking on the whole microbial community proved useful in outlining processes that conventional tracers did not capture, such as the occurrence of a localised domestic contamination in the upper catchment, and the inflow of agricultural runoff all along the river profile during the wet season. Our study emphasises the role of rivers as biogeochemical reactors that constantly process and transform contaminants and microbial communities. We also demonstrate the value of using isotopic, chemical and microbial tools together to trace the movement of water and contaminants through urban rivers.
The influence of climate on water chemistry states and dynamics in rivers across Australia
Publisher: Wiley
Date: 12-2021
DOI: 10.1002/HYP.14423
Abstract: For effective water quality management and policy development, spatial variability in the mean concentrations and dynamics of riverine water quality needs to be understood. Using water chemistry (calcium, electrical conductivity, nitrate‐nitrite, soluble reactive phosphorus, total nitrogen, total phosphorus and total suspended solids) data for up to 578 locations across the Australian continent, we assessed the impact of climate zones (arid, Mediterranean, temperate, subtropical, tropical) on (i) inter‐annual mean concentration and (ii) water chemistry dynamics as represented by constituent export regimes (ratio of the coefficients of variation of concentration and discharge) and export patterns (slope of the concentration‐discharge relationship). We found that inter‐annual mean concentrations vary significantly by climate zones and that spatial variability in water chemistry generally exceeds temporal variability. However, export regimes and patterns are generally consistent across climate zones. This suggests that intrinsic properties of in idual constituents rather than catchment properties determine export regimes and patterns. The spatially consistent water chemistry dynamics highlights the potential to predict riverine water quality across the Australian continent, which can support national riverine water quality management and policy development.
Exploratory radioisotope measurements suggest that in-stream erosion represents the main sediment source in a pristine, tropical rainforest in Costa Rica
Publisher: Springer Science and Business Media LLC
Date: 05-09-2022
Tracing sediment sources in a tropical highland catchment of central Mexico by using conventional and alternative fingerprinting methods
Publisher: Wiley
Date: 18-06-2012
DOI: 10.1002/HYP.9421
Stream respiration exceeds CO2 evasion in a low-energy, oligotrophic tropical stream
Publisher: Wiley
Date: 12-03-2023
DOI: 10.1002/LNO.12334
Abstract: Carbon dioxide (CO 2 ) can be either imported to streams through groundwater and subsurface inputs of soil‐respired CO 2 or produced internally through stream metabolism. The contribution of each source to the CO 2 evasion flux from streams is not well quantified, especially in the tropics, an underrepresented region in carbon (C) cycling studies. We used high‐frequency measurements of dissolved O 2 and CO 2 concentrations to estimate the potential contribution of stream metabolism to the CO 2 evasion flux in a tropical lowland headwater stream. We found that the stream was heterotrophic all year round, with net ecosystem productivity (NEP) values ranging from 0.84 to 4.06 g C m −2 d −1 (median 1.29 g C m −2 d −1 here we expressed gross primary productivity (GPP) as a negative flux and ecosystem respiration (ER) as a positive flux). Positive NEP values were the result of a relatively low and stable GPP through the seasons, compared to a higher and more variable ER favored by the high temperatures and organic matter availability, particularly during the wet season. The CO 2 evasion flux was relatively low due to low turbulence (median: 1.09 g C m −2 d −1 ). As a result, daily NEP rates exceeded the CO 2 evasion flux with a potential contribution of 129% (median 120–175% interquartile range), despite the strong seasonal changes in flow regime and landscape connectivity. The CO 2 excess was likely transported downstream, where it was ultimately emitted to the atmosphere. Our results highlight the overwhelming importance of ER to the C cycle of low‐energy, oligotrophic tropical streams.
End member and Bayesian mixing models consistently indicate near‐surface flowpath dominance in a pristine humid tropical rainforest
Publisher: Wiley
Date: 04-2021
DOI: 10.1002/HYP.14153
Seasonal Shift From Biogenic to Geogenic Fluvial Carbon Caused by Changing Water Sources in the Wet‐Dry Tropics
Publisher: American Geophysical Union (AGU)
Date: 02-2020
DOI: 10.1029/2019JG005384
Increase in surface runoff in the central mountains of Mexico: lessons from the past and predictive scenario for the next century
Publisher: Copernicus GmbH
Date: 12-02-2010
Abstract: Abstract. The hydrological response of a medium scale mountainous watershed (Mexico) is analysed over half a century. The hydrograph separation highlights an increasing surface runoff contribution since the early 1970's. This increase is attributed to land use changes while the meteorological forcing (rains) remains statistically stable over the same period. As a consequence, the intensity of annual extreme floods has tripled up over the period of survey, increasing flood risks in the region. The paper ends with a climatic projection over the 21st century. The decrease of precipitation and the increase of temperature should accentuate the trend engaged since the 1970's by reducing groundwater resources and increasing surface-runoff and associated risks.
Cavitron extraction of xylem water suggests cryogenic extraction biases vary across species but are independent of tree water stress
Publisher: Authorea, Inc.
Date: 30-10-2023
Carbon, nitrogen, phosphorus, and sediment sources and retention in a small eutrophic tropical reservoir
Publisher: Springer Science and Business Media LLC
Date: 22-08-2015
Synthesizing the impacts of baseflow contribution on concentration–discharge (<i>C</i>–<i>Q</i>) relationships across Australia using a Bayesian
Publisher: Copernicus GmbH
Date: 03-01-2022
Abstract: Abstract. Understanding concentration–discharge (C–Q) relationships can inform catchment solute and particulate export processes. Previous studies have shown that the extent to which baseflow contributes to streamflow can affect C–Q relationships in some catchments. However, the current understanding on the effects of baseflow contribution in shaping the C–Q patterns is largely derived from temperate catchments. As such, we still lack quantitative understanding of these effects across a wide range of climates (e.g. arid, tropical and subtropical). The study aims to assess how baseflow contributions, as defined by the median and the range of daily baseflow indices within in idual catchments (BFI_m and BFI_range, respectively), influence C–Q slopes across 157 catchments in Australia spanning five climate zones. This study focuses on six water quality variables: electrical conductivity (EC), total phosphorus (TP), soluble reactive phosphorus (SRP), total suspended solids (TSS), the sum of nitrate and nitrite (NOx) and total nitrogen (TN). The impact of baseflow contributions is explored with a novel Bayesian hierarchical model. For sediments and nutrient species (TSS, NOx, TN and TP), we generally see largely positive C–Q slopes, which suggest a dominance of mobilization export patterns. Further, for TSS, NOx and TP we see stronger mobilization (steeper positive C–Q slopes) in catchments with higher values in both the BFI_m and BFI_range, as these two metrics are positively correlated for most catchments. The enhanced mobilization in catchments with higher BFI_m or BFI_range is likely due to the more variable flow pathways that occur in catchments with higher baseflow contributions. These variable flow pathways can lead to higher concentration gradients between low flows and high flows, where the former is generally dominated by groundwater/slow subsurface flow while the latter by surface water sources, respectively. This result highlights the crucial role of flow pathways in determining catchment exports of solutes and particulates. Our study also demonstrates the need for further studies on how the temporal variations of flow regimes and baseflow contributions influence flow pathways and the potential impacts of these flow pathways on catchment C–Q relationships.
Controls on Spatial Variability in Mean Concentrations and Export Patterns of River Chemistry Across the Australian Continent
Publisher: American Geophysical Union (AGU)
Date: 12-2022
DOI: 10.1029/2022WR032365
Abstract: The state and dynamics of river chemistry are influenced by both anthropogenic and natural catchment characteristics. However, understanding key controls on catchment mean concentrations and export patterns comprehensively across a wide range of climate zones is still lacking, as most of this research is focused on temperate regions. In this study, we investigate the catchment controls on mean concentrations and export patterns (concentration – discharge relationship, C–Q slope) of river chemistry, using a long‐term data set of up to 507 sites spanning five climate zones (i.e., arid, Mediterranean, temperate, subtropical, tropical) across the Australian continent. We use Bayesian model averaging (BMA) and hierarchical modeling (BHM) approaches to predict the mean concentrations and export patterns and compare the relative importance of 26 catchment characteristics (e.g., topography, climate, land use, land cover, soil properties and hydrology). Our results demonstrate that mean concentrations result from the interaction of catchment indicators and anthropogenic factors (i.e., land use, topography and soil), while export patterns are influenced by topography. We also found that incorporating the effects of climate zones in a BHM framework improved the predictability of both mean concentrations and C–Q slopes, suggesting the importance of climatic controls on hydrological and biogeochemical processes. Our study provides insights into the contrasting effects of catchment controls across different climate zones. Investigating those controls can inform sustainable water quality management strategies that consider the potential changes in river chemistry state and export behavior.
Groundwater‐Derived DIC and Carbonate Buffering Enhance Fluvial CO2 Evasion in Two Australian Tropical Rivers
Publisher: American Geophysical Union (AGU)
Date: 02-2019
DOI: 10.1029/2018JG004912
Related Organisations
Related Funding Activities
Discovery Early Career Researcher Award - Grant ID: DE220100852
Start Date: 2022
End Date: 12-2024
Amount: $455,766.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP220100823
Start Date: 04-2023
End Date: 04-2026
Amount: $508,976.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP210300151
Start Date: 2024
End Date: 12-2028
Amount: $935,882.00
Funder: Australian Research Council
View Funded Activity