Ruth Reef

Historical analysis of mangrove leaf traits throughout the 19th and 20th centuries reveals differential responses to increases in atmospheric CO2

Publisher: Wiley

Date: 16-09-2014

DOI: 10.1111/GEB.12211

The effect of atmospheric carbon dioxide concentrations on the performance of the mangroveAvicennia germinansover a range of salinities

Publisher: Wiley

Date: 05-11-2014

DOI: 10.1111/PPL.12289

Abstract: By increasing water use efficiency and carbon assimilation, increasing atmospheric CO2 concentrations could potentially improve plant productivity and growth at high salinities. To assess the effect of elevated CO2 on the salinity response of a woody halophyte, we grew seedlings of the mangrove Avicennia germinans under a combination of five salinity treatments [from 5 to 65 parts per thousand (ppt)] and three CO2 concentrations (280, 400 and 800 ppm). We measured survivorship, growth rate, photosynthetic gas exchange, root architecture and foliar nutrient and ion concentrations. The salinity optima for growth shifted higher with increasing concentrations of CO2 , from 0 ppt at 280 ppm to 35 ppt at 800 ppm. At optimal salinity conditions, carbon assimilation rates were significantly higher under elevated CO2 concentrations. However, at salinities above the salinity optima, salinity had an expected negative effect on mangrove growth and carbon assimilation, which was not alleviated by elevated CO2 , despite a significant improvement in photosynthetic water use efficiency. This is likely due to non-stomatal limitations to growth at high salinities, as indicated by our measurements of foliar ion concentrations that show a displacement of K(+) by Na(+) at elevated salinities that is not affected by CO2 . The observed shift in the optimal salinity for growth with increasing CO2 concentrations changes the fundamental niche of this species and could have significant effects on future mangrove distribution patterns and interspecific interactions.

Global coastal wetland change under sea-level rise and related stresses: The DIVA Wetland Change Model

Publisher: Elsevier BV

Date: 04-2016

DOI: 10.1016/J.GLOPLACHA.2015.12.018

The effect of vegetation height and biomass on the sediment budget of a European saltmarsh

Publisher: Elsevier BV

Date: 03-2018

DOI: 10.1016/J.ECSS.2017.12.016

Quantification of Coastal Change and Preliminary Sediment Budget Calculation Using SfM Photogrammetry and Archival Aerial Imagery

Publisher: MDPI AG

Date: 26-09-2022

DOI: 10.3390/GEOSCIENCES12100357

Abstract: A preliminary sediment budget for the sandy shores flanking the entrance to Western Port, a large bay in Australia, was formulated using a comparison between two Digital Surface Models (DSMs) with a 30-year interval and auxiliary shoreline data. The 1977 DSM was generated from ten aerial photographs using Structure-from-Motion (SfM) photogrammetry. Assessment of its accuracy obtained an RMSE of 0.48 m with most of the independent points overpredicting or underpredicting elevations by less than 0.5 m following manual point cloud cleaning. This technique created a 7.5 km2 surface with a Ground S ling Distance of 34.3 cm between two coastal towns separated by a narrow channel. Comparison of the 1977 DSM to a second, light detection and ranging (LiDAR)-derived DSM from 2007 showed that a volume of ~200,000 m3 of sediment (above Mean Sea Level) was deposited at Newhaven Beach on Phillip Island, while, during the same period, ~40,000 m3 of sediment was lost from the mainland beaches of San Remo, on the eastern side of the channel. Shoreline positions extracted from aerial photographs taken in 1960 and a nautical chart published one century earlier indicate that the progradation experienced at Newhaven Beach has been possible due to provision of sediment via destabilisation of the vegetation covering the updrift Woolamai isthmus on the southeast coast of Phillip Island, whereas the retreat observed at San Remo Beach since 1960 can be attributed to the natural dynamics of the entrance, which appears to favour flood-dominance on the western side and ebb-dominance on the eastern side. While a more comprehensive balance of volumes entering and exiting the area would specifically benefit from volumetric assessments of the subaqueous part of the entrance, the general usefulness of quantifying coastal change using SfM and historical photographs is demonstrated.

A Review of Spectral Indices for Mangrove Remote Sensing

Publisher: MDPI AG

Date: 29-09-2022

DOI: 10.3390/RS14194868

Abstract: Mangrove ecosystems provide critical goods and ecosystem services to coastal communities and contribute to climate change mitigation. Over four decades, remote sensing has proved its usefulness in monitoring mangrove ecosystems on a broad scale, over time, and at a lower cost than field observation. The increasing use of spectral indices has led to an expansion of the geographical context of mangrove studies from local-scale studies to intercontinental and global analyses over the past 20 years. In remote sensing, numerous spectral indices derived from multiple spectral bands of remotely sensed data have been developed and used for multiple studies on mangroves. In this paper, we review the range of spectral indices produced and utilised in mangrove remote sensing between 1996 and 2021. Our findings reveal that spectral indices have been used for a variety of mangrove aspects but excluded identification of mangrove species. The included aspects are mangrove extent, distribution, mangrove above ground parameters (e.g., carbon density, biomass, canopy height, and estimations of LAI), and changes to the aforementioned aspects over time. Normalised Difference Vegetation Index (NDVI) was found to be the most widely applied index in mangroves, used in 82% of the studies reviewed, followed by the Enhanced Vegetation Index (EVI) used in 28% of the studies. Development and application of potential indices for mangrove cover characterisation has increased (currently 6 indices are published), but NDVI remains the most popular index for mangrove remote sensing. Ultimately, we identify the limitations and gaps of current studies and suggest some future directions under the topic of spectral index application in connection to time series imagery and the fusion of optical sensors for mangrove studies in the digital era.

Contemporary rates of carbon sequestration through vertical accretion of sediments in mangrove forests and saltmarshes of South East Queensland, Australia

Publisher: Springer Science and Business Media LLC

Date: 06-09-2014

DOI: 10.1007/S12237-013-9702-4

Intense storms and the delivery of materials that relieve nutrient limitations in mangroves of an arid zone estuary

Publisher: CSIRO Publishing

Date: 2020

DOI: 10.1071/FP11027

Abstract: Tropical cyclones can be devastating to ecosystems, but they can also result in pulses of fresh water and sediments delivered in floodwaters to the coastal zone. In the arid zone the pulses provided by cyclones may be particularly important for the maintenance of productivity. We examined the impacts of Cyclone Pancho on growth and nutrient limitations to growth in mangroves on the arid coast of Western Australia. We found that growth of trees was enhanced after the cyclone, more than doubling their rates of stem extension. Fertilisation studies showed that before the cyclone tree growth was nutrient limited. After the cyclone fertilisation treatments had no significant effect on growth, indicating nutrients had been delivered during the storm. Additionally, before the cyclone the efficiency of resorption of phosphorus and nitrogen from senescent leaves was higher than after the cyclone, suggesting that nutrient availability was enhanced. Analysis of stable isotopes of leaf tissue indicated that the cyclone was associated with small changes in water use efficiency, consistent with decreased soil salinity associated with the cyclone. There was, however, significant reductions in δ15N indicating enhanced N supply potentially from a new source. We conclude that in the arid zone, floodwater associated with cyclones is important for the delivery of nutrient subsidies that stimulate mangrove growth and that predicted future reductions in the frequency of cyclones will have negative impacts on the productivity of these ecosystems.

Near-bottom depletion of zooplankton over coral reefs: III: vertical gradient of predation pressure

Publisher: Springer Science and Business Media LLC

Date: 02-02-2005

DOI: 10.1007/S00338-004-0451-5

How mangrove forests adjust to rising sea level

Publisher: Wiley

Date: 19-11-2014

DOI: 10.1111/NPH.12605

Abstract: Mangroves are among the most well described and widely studied wetland communities in the world. The greatest threats to mangrove persistence are deforestation and other anthropogenic disturbances that can compromise habitat stability and resilience to sea‐level rise. To persist, mangrove ecosystems must adjust to rising sea level by building vertically or become submerged. Mangroves may directly or indirectly influence soil accretion processes through the production and accumulation of organic matter, as well as the trapping and retention of mineral sediment. In this review, we provide a general overview of research on mangrove elevation dynamics, emphasizing the role of the vegetation in maintaining soil surface elevations (i.e. position of the soil surface in the vertical plane). We summarize the primary ways in which mangroves may influence sediment accretion and vertical land development, for ex le, through root contributions to soil volume and upward expansion of the soil surface. We also examine how hydrological, geomorphological and climatic processes may interact with plant processes to influence mangrove capacity to keep pace with rising sea level. We draw on a variety of studies to describe the important, and often under‐appreciated, role that plants play in shaping the trajectory of an ecosystem undergoing change. Contents Summary 19 I. Introduction 19 II. Important characteristics of mangrove ecosystems 20 III. Patterns of elevation change in mangroves 20 IV. Biological influences on accretion and elevation change 21 V. Factors affecting root contributions to vertical soil development 26 VI. Some potential climatic and environmental feedbacks 29 VII. Perspectives 30 Acknowledgements 31 References 31

Coastal wetland management in the Great Barrier Reef: Farmer perceptions

Publisher: Wiley

Date: 29-07-2021

DOI: 10.1111/1745-5871.12497

Abstract: Poor water quality caused by intensive sugarcane farming has been among the main causes of coastal degradation around the Great Barrier Reef (GBR). Despite regulations and incentives, water quality in the GBR has yet to reach government targets, and there is an urgent need to investigate alternative management approaches. In this study, we have employed a social‐ecological approach to understand farmers' attitudes to existing nutrient and sediment management approaches, assess farmers' perceptions of managing coastal wetlands to ameliorate agricultural run‐off, and propose how these findings could inform integrative policy development for the GBR. We conducted semi‐structured interviews with sugarcane farmers in the Wet Tropics to understand perceptions of ecosystem services, coastal wetlands and industry challenges. We linked our analysis of key issues of concern to farmers with broader environmental and land use issues and have outlined future policy considerations in the face of socio‐economic and climatic change. Our conclusions emphasise the need to rethink future land tenure in low‐lying areas of North Queensland, the importance of considering ecosystem services provided by coastal wetlands in policy models and the need for a payments for ecosystem services (PES) model to safeguard the future of the GBR.

The contrasting effects of nutrient enrichment on growth, biomass allocation and decomposition of plant tissue in coastal wetlands

Publisher: Springer Science and Business Media LLC

Date: 20-02-2017

DOI: 10.1007/S11104-017-3206-0

Ultraviolet absorbing compounds provide a rapid response mechanism for UV protection in some reef fish

Publisher: Elsevier BV

Date: 07-2016

DOI: 10.1016/J.JPHOTOBIOL.2016.04.020

Abstract: The external mucus surface of reef fish contains ultraviolet absorbing compounds (UVAC), most prominently Mycosporine-like Amino Acids (MAAs). MAAs in the external mucus of reef fish are thought to act as sunscreens by preventing the damaging effects of ultraviolet radiation (UVR), however, direct evidence for their protective role has been missing. We tested the protective function of UVAC's by exposing fish with naturally low, Pomacentrus amboinensis, and high, Thalassoma lunare, mucus absorption properties to a high dose of UVR (UVB: 13.4W∗m(-2), UVA: 6.1W∗m(-2)) and measuring the resulting DNA damage in the form of cyclobutane pyrimidine dimers (CPDs). For both species, the amount of UV induced DNA damage sustained following the exposure to a 1h pulse of high UVR was negatively correlated with mucus absorbance, a proxy for MAA concentration. Furthermore, a rapid and significant increase in UVAC concentration was observed in P. amboinensis following UV exposure, directly after capture and after ten days in captivity. No such increase was observed in T. lunare, which maintained relatively high levels of UV absorbance at all times. P. amboinensis, in contrast to T. lunare, uses UV communication and thus must maintain UV transparent mucus to be able to display its UV patterns. The ability to rapidly alter the transparency of mucus could be an important adaptation in the trade off between protection from harmful UVR and UV communication.

Photoreactivation is the main repair pathway for UV-induced DNA damage in coral planulae

Publisher: The Company of Biologists

Date: 09-2009

DOI: 10.1242/JEB.031286

Abstract: The larvae of most coral species spend some time in the plankton, floating just below the surface and hence exposed to high levels of ultraviolet radiation (UVR). The high levels of UVR are potentially stressful and damaging to DNA and other cellular components, such as proteins, reducing survivorship. Consequently, mechanisms to either shade (prevent) or repair damage potentially play an important role. In this study, the role of photoreactivation in the survival of coral planulae was examined. Photoreactivation is a light-stimulated response to UV-damaged DNA in which photolyase proteins repair damaged DNA. Photoreactivation rates, as well as the localization of photolyase, were explored in planulae under conditions where photoreactivation was or was not inhibited. The results indicate that photoreactivation is the main DNA repair pathway in coral planulae, repairing UV-induced DNA damage swiftly (K=1.75 h–1 and a half-life of repair of 23 min), with no evidence of any light-independent DNA repair mechanisms, such as nucleotide excision repair (NER), at work. Photolyase mRNA was localized to both the ectoderm and endoderm of the larvae. The amount of cell death in the coral planulae increased significantly when photoreactivation was inhibited, by blocking photoreactivating light. We found that photoreactivation, along with additional UV shielding in the form of five mycosporine-like amino acids, are sufficient for survival in surface tropical waters and that planulae do not accumulate DNA damage despite being exposed to high UVR.

The response of the mangrove Avicennia marina to heterogeneous salinity measured using a split-root approach

Publisher: Springer Science and Business Media LLC

Date: 05-05-2015

DOI: 10.1007/S11104-015-2489-2

Interactive effects of climate and nutrient enrichment on patterns of herbivory by different feeding guilds in mangrove forests

Publisher: Wiley

Date: 28-09-2017

DOI: 10.1111/GEB.12644

Using eDNA to determine the source of organic carbon in seagrass meadows

Publisher: Wiley

Date: 30-03-2017

DOI: 10.1002/LNO.10499

Nutrition of mangroves

Publisher: Oxford University Press (OUP)

Date: 21-06-2010

DOI: 10.1093/TREEPHYS/TPQ048

Abstract: Mangrove forests dominate the world's tropical and subtropical coastlines. Similar to other plant communities, nutrient availability is one of the major factors influencing mangrove forest structure and productivity. Many mangrove soils have extremely low nutrient availability, although nutrient availability can vary greatly among and within mangrove forests. Nutrient-conserving processes in mangroves are well developed and include evergreeness, resorption of nutrients prior to leaf fall, the immobilization of nutrients in leaf litter during decomposition, high root/shoot ratios and the repeated use of old root channels. Both nitrogen-use efficiency and nutrient resorption efficiencies in mangroves are amongst the highest recorded for angiosperms. A complex range of interacting abiotic and biotic factors controls the availability of nutrients to mangrove trees, and mangroves are characteristically plastic in their ability to opportunistically utilize nutrients when these become available. Nitrogen and phosphorus have been implicated as the nutrients most likely to limit growth in mangroves. Ammonium is the primary form of nitrogen in mangrove soils, in part as a result of anoxic soil conditions, and tree growth is supported mainly by ammonium uptake. Nutrient enrichment is a major threat to marine ecosystems. Although mangroves have been proposed to protect the marine environment from land-derived nutrient pollution, nutrient enrichment can have negative consequences for mangrove forests and their capacity for retention of nutrients may be limited.

Variable effects of nutrient enrichment on soil respiration in mangrove forests

Publisher: Springer Science and Business Media LLC

Date: 15-02-2014

DOI: 10.1007/S11104-014-2036-6

Correction to: Attracting, Retaining and Sustaining Early Childhood Teachers: An Ecological Conceptualisation of Workforce Issues and Future Research Directions

Publisher: Springer Science and Business Media LLC

Date: 12-03-2021

DOI: 10.1007/S13384-021-00441-Z

Sensitivity of dissolved organic carbon exchange and sediment bacteria to water quality in mangrove forests

Publisher: Springer Science and Business Media LLC

Date: 27-03-2012

DOI: 10.1007/S10750-012-1071-7

Future response of global coastal wetlands to sea-level rise

Publisher: Springer Science and Business Media LLC

Date: 09-2018

DOI: 10.1038/S41586-018-0476-5

Abstract: The response of coastal wetlands to sea-level rise during the twenty-first century remains uncertain. Global-scale projections suggest that between 20 and 90 per cent (for low and high sea-level rise scenarios, respectively) of the present-day coastal wetland area will be lost, which will in turn result in the loss of bio ersity and highly valued ecosystem services

The effect of nutrient enrichment on the growth, nucleic acid concentrations, and elemental stoichiometry of coral reef macroalgae

Publisher: Wiley

Date: 16-07-2012

DOI: 10.1002/ECE3.330

Swimming Against the Flow: A Mechanism of Zooplankton Aggregation

Publisher: American Association for the Advancement of Science (AAAS)

Date: 06-05-2005

DOI: 10.1126/SCIENCE.1107834

Abstract: Zooplankton reside in a constantly flowing environment. However, information about their response to ambient flow has remained elusive, because of the difficulties of following the in idual motions of these minute, nearly transparent animals in the ocean. Using a three-dimensional acoustic imaging system, we tracked ,000 zooplankters at two coastal sites in the Red Sea. Resolution of their motion from that of the water showed that the animals effectively maintained their depth by swimming against upwelling and downwelling currents moving at rates of up to tens of body lengths per second, causing their accumulation at frontal zones. This mechanism explains how oceanic fronts become major feeding grounds for predators and targets for fishermen.

The vulnerability of Indo-Pacific mangrove forests to sea-level rise

Publisher: Springer Science and Business Media LLC

Date: 10-2015

DOI: 10.1038/NATURE15538

Abstract: Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world's mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.

Coral skeletons defend against ultraviolet radiation

Publisher: Public Library of Science (PLoS)

Date: 25-11-2009

DOI: 10.1371/JOURNAL.PONE.0007995

Mangroves provide blue carbon ecological value at a low freshwater cost

Publisher: Springer Science and Business Media LLC

Date: 20-02-2018

DOI: 10.1038/S41598-022-21514-8

Abstract: “Blue carbon” wetland vegetation has a limited freshwater requirement. One type, mangroves, utilizes less freshwater during transpiration than adjacent terrestrial ecoregions, equating to only 43% (average) to 57% (potential) of evapotranspiration ( $$ET$$ ET ). Here, we demonstrate that comparative consumptive water use by mangrove vegetation is as much as 2905 kL H 2 O ha −1 year −1 less than adjacent ecoregions with $${E}_{c}$$ E c -to- $$ET$$ ET ratios of 47–70%. Lower porewater salinity would, however, increase mangrove $${E}_{c}$$ E c -to- $$ET$$ ET ratios by affecting leaf-, tree-, and stand-level eco-physiological controls on transpiration. Restricted water use is also additive to other ecosystem services provided by mangroves, such as high carbon sequestration, coastal protection and support of bio ersity within estuarine and marine environments. Low freshwater demand enables mangroves to sustain ecological values of connected estuarine ecosystems with future reductions in freshwater while not competing with the freshwater needs of humans. Conservative water use may also be a characteristic of other emergent blue carbon wetlands.

The use of fresh and saline water sources by the mangrove Avicennia marina

Publisher: Springer Science and Business Media LLC

Date: 05-11-2015

DOI: 10.1007/S10750-014-2091-2

The effects of CO2 and nutrient fertilisation on the growth and temperature response of the mangrove Avicennia germinans

Publisher: Springer Science and Business Media LLC

Date: 03-06-2016

DOI: 10.1007/S11120-016-0278-2

Abstract: In order to understand plant responses to both the widespread phenomenon of increased nutrient inputs to coastal zones and the concurrent rise in atmospheric CO2 concentrations, CO2-nutrient interactions need to be considered. In addition to its potential stimulating effect on photosynthesis and growth, elevated CO2 affects the temperature response of photosynthesis. The scarcity of experiments testing how elevated CO2 affects the temperature response of tropical trees hinders our ability to model future primary productivity. In a glasshouse study, we examined the effects of elevated CO2 (800 ppm) and nutrient availability on seedlings of the widespread mangrove Avicennia germinans. We assessed photosynthetic performance, the temperature response of photosynthesis, seedling growth and biomass allocation. We found large synergistic gains in both growth (42 %) and photosynthesis (115 %) when seedlings grown under elevated CO2 were supplied with elevated nutrient concentrations relative to their ambient growing conditions. Growth was significantly enhanced under elevated CO2 only under high-nutrient conditions, mainly in above-ground tissues. Under low-nutrient conditions and elevated CO2, root volume was more than double that of seedlings grown under ambient CO2 levels. Elevated CO2 significantly increased the temperature optimum for photosynthesis by ca. 4 °C. Rising CO2 concentrations are likely to have a significant positive effect on the growth rate of A. germinans over the next century, especially in areas where nutrient availability is high.

Understanding why apprentices consider dropping out: longitudinal prediction of apprentices’ workplace interest and anxiety

Publisher: Springer Science and Business Media LLC

Date: 03-2021

DOI: 10.1186/S40461-020-00106-8

Abstract: Although apprenticeships ease the school-to-work transition for youth, many apprentices seriously consider dropping out. While associated with noncompletions, dropout considerations are important to study in their own right, because they reflect a negative quality of apprenticeship experience and can impact apprentices’ quality of learning and engagement. Few studies have addressed apprentices’ dropout considerations using comprehensive theoretical frameworks. To address this gap, this study examined how apprentices’ interest and anxiety growth trajectories predicted dropout considerations and associated with perceived resources and demands, grounded in expectancy-value theory (EVT) and the job demands-resources (JD-R) model. Australian apprentices ( N = 2387) were surveyed at 6-month intervals utilising an accelerated longitudinal design, on their workplace interest and anxiety, job-related resources (role model, timing of choice, employer teaching, expertise, job security, and training wages) and demands (lack of information, career indecision, and excessive work). Latent growth models (LGM) within a structural equation modelling framework showed apprentices began with high interest which declined over time, and low anxiety which increased in the latter half of their first year until the end of their second year. Apprentices’ dropout considerations were predicted by initial interest and anxiety levels (at the beginning of their apprenticeship), and by interest losses during their apprenticeship (but, not by increases in anxiety). Almost half the variance in interest and anxiety trajectories was explained by apprentices’ perceived resources and demands: resources had a greater effect on promoting interest than reducing anxiety, whereas demands were more important in exacerbating anxiety.

Attracting, retaining and sustaining early childhood teachers: an ecological conceptualisation of workforce issues and future research directions

Publisher: Springer Science and Business Media LLC

Date: 11-01-2021

DOI: 10.1007/S13384-020-00424-6

Isotopic signatures of stem water reveal differences in water sources accessed by mangrove tree species

Publisher: Springer Science and Business Media LLC

Date: 08-03-2017

DOI: 10.1007/S10750-017-3149-8

Mammalian herbivores in Australia transport nutrients from terrestrial to marine ecosystems via mangroves

Publisher: Cambridge University Press (CUP)

Date: 20-02-2014

DOI: 10.1017/S0266467414000054

Abstract: Nutrient subsidies from one ecosystem to another serve a critical link among ecosystems. The transfer of materials across the terrestrial-to-marine boundary is considered to be driven by hydrological connectivity, but animal movement can provide another pathway for nutrient transfers. In two separate studies we assessed the role mammals (bats and kangaroos) play in alleviating nutrient limitation in mangrove forests in Australia. At Lizard Island, we measured tree growth and foliar elemental and isotopic composition of trees growing within and outside a large flying fox roost. In Western Australia, we measured foliar elemental and isotopic composition of trees within two forests frequented by kangaroos that feed in spinifex grasslands and shelter in the shade of the mangroves. We compared those with mangroves from adjacent forests that are not frequented by kangaroos. We show that at both locations, the mangrove forest receives terrestrial nutrient subsidies through animal movement. At Lizard Island dominant mangrove species were significantly enriched in nitrogen within the bat roost, as evidenced by higher foliar N concentrations (by up to 150%), N:P and N:C ratios in trees within the roost compared with trees outside the roost. The isotopic signature of foliar N was significantly enriched in 15 N by 1–3‰ within the roost, further suggesting that the source of the N enrichment was the bat roost. Growth rates of mangroves within the roost were nearly six times higher than trees outside the roost. In the arid coast of Western Australia, we show elevated foliar 15 N abundance of up to 3‰ in mangroves where kangaroos shelter relative to trees where they do not. Thus, this study presents two ex les for mammalian herbivore mediated localized transport of nutrients from terrestrial to marine ecosystems, consequently affecting mangrove tree growth, productivity and forest structure.

Sea level and turbidity controls on mangrove soil surface elevation change

Publisher: Elsevier BV

Date: 02-2015

DOI: 10.1016/J.ECSS.2014.11.026

Mangrove root biomass and the uncertainty of belowground carbon estimations

Publisher: Elsevier BV

Date: 11-2017

DOI: 10.1016/J.FORECO.2017.08.016

Differential responses of the mangrove Avicennia marina to salinity and abscisic acid

Publisher: CSIRO Publishing

Date: 2012

DOI: 10.1071/FP12178

Abstract: Salinisation of the soil can cause plant water deficits, ion and nutrient imbalances and toxic reactions. The halophyte, Avicennia marina (Forssk.) Vierh., is a mangrove that tolerates a wide range of soil salinities. In order to understand how salinity affects plant growth and functioning and how salinity responses are influenced by the water deficit signalling hormone abscisic acid (ABA) we grew A. marina seedlings under two non-growth limiting salinities: 60% seawater and 90% seawater and with and without exogenously supplied ABA. We measured growth, photosynthesis, sap flow, aquaporin gene expression, hydraulic anatomy and nutrient status as well as sap ABA concentrations. ABA addition resulted in a drought phenotype (reduced sap flow, transpiration rates and photosynthesis and increased water use efficiency and aquaporin expression). In contrast, growth in high salinity did not lead to responses that are typical for water deficits, but rather, could be characterised as drought avoidance strategies (no reduction in sap flow, transpiration rates and photosynthesis and reduced aquaporin expression). Tissue nutrient concentrations were higher in seedlings grown at high salinities. We did not find evidence for a role for ABA in the mangrove salinity response, suggesting ABA is not produced directly in response to high concentrations of NaCl ions.

Regulation of water balance in mangroves

Publisher: Oxford University Press (OUP)

Date: 25-08-2014

DOI: 10.1093/AOB/MCU174

Variation in elemental stoichiometry and RNA: DNA in four phyla of benthic organisms from coral reefs

Publisher: Wiley

Date: 10-03-2014

DOI: 10.1111/1365-2435.12256

Boys’ motivation profiles in mathematics: relations with contextual factors, wellbeing and engagement in a boys-only school

Publisher: Springer Science and Business Media LLC

Date: 19-01-2023

DOI: 10.1007/S11858-022-01464-1

Abstract: This study examined the extent to which boys fell into clusters comprised of different levels of motivations and costs. In turn, the antecedents of these clusters and associations with engagement and wellbeing outcomes were considered. Based on survey responses from 168 students across Years 5, 7 and 9 from an all-boys' school in Sydney, Australia, three clusters were identified: Positively Engaged, Disengaged , and Struggling Ambitious . Performance-approach and avoidance achievement goals, mastery classroom goal structure, perceived peer valuing of mathematics and teacher enthusiasm differentially predicted profile membership. Clusters were also found to differ in terms of both wellbeing and engagement, such that students within maladaptive profiles evidenced the most negative outcomes. The study reaffirms prior work, holds implications for addressing student motivation in mathematics, and adds to understanding of the interplay of in idual and classroom goal structures in relation to students’ mathematics expectancies, values and resultant outcomes.

The effects of elevated CO2 and eutrophication on surface elevation gain in a European salt marsh

Publisher: Wiley

Date: 09-07-2017

DOI: 10.1111/GCB.13396

Abstract: Salt marshes can play a vital role in mitigating the effects of global environmental change by dissipating incident storm wave energy and, through accretion, tracking increasing water depths consequent upon sea level rise. Atmospheric CO

Ichthyofauna of the rocky coastal littoral of the Israeli Mediterranean, with reference to the paucity of Red Sea (Lessepsian) migrants in this habitat

Publisher: Informa UK Limited

Date: 10-2007

DOI: 10.1080/17451000701635110

The Physiology of Mangrove Trees with Changing Climate

Publisher: Springer International Publishing

Date: 2016

DOI: 10.1007/978-3-319-27422-5_7

Nutrient exchange of extensive cyanobacterial mats in an arid subtropical wetland

Publisher: CSIRO Publishing

Date: 2012

DOI: 10.1071/MF11133

Abstract: Cyanobacterial mats cover extensive areas of subtropical arid coastal wetlands and are sites of active nutrient exchange. To assess spatial (low v. high in the intertidal zone) and temporal (day v. night) variability in nitrogen (N) exchange in arid Exmouth Gulf, Western Australia, we measured nutrient exchange (NOx–-N, NH4+ and soluble reactive phosphorus) during tidal inundation and N fixation of cyanobacterial mats before and during an unusual period of heavy rainfall. Additionally, we investigated the species composition within the cyanobacterial mat. We hypothesised that nutrients are released to the floodwater during tidal inundation, that N fixation is a significant path of N incorporation, that highest N fixation rates occur in the low intertidal zone at night, and that the cyanobacterial mat community composition varies across the intertidal zone. Our results showed that nutrients were removed from the floodwater during tidal inundation. N fixation accounted for 34% of N incorporation, with highest rates in the lower intertidal zone during the day. The cyanobacterial mat was dominated by Microcoleus chthonoplastes, but composition varied across the intertidal zone. The present study provided evidence of temporal and spatial variability in nutrient exchange and implied an important role of cyanobacterial mats in coastal production.

Importance of macro- versus microstructure in modulating light levels inside coral colonies

Publisher: Wiley

Date: 05-07-2011

DOI: 10.1111/J.1529-8817.2011.01021.X

Abstract: Adjusting the light exposure and capture of their symbiotic photosynthetic dinoflagellates (genus Symbiodinium Freud.) is central to the success of reef-building corals (order Scleractinia) across high spatio-temporal variation in the light environment of coral reefs. We tested the hypothesis that optical properties of tissues in some coral species can provide light management at the tissue scale comparable to light modulation by colony architecture in other species. We compared within-tissue scalar irradiance in two coral species from the same light habitat but with contrasting colony growth forms: branching Stylophora pistillata and massive Lobophyllia corymbosa. Scalar irradiance at the level of the symbionts (2 mm into the coral tissues) were <10% of ambient irradiance and nearly identical for the two species, despite substantially different light environments at the tissue surface. In S. pistillata, light attenuation (90% relative to ambient) was observed predominantly at the colony level as a result of branch-to-branch self-shading, while in L. corymbosa, near-complete light attenuation (97% relative to ambient) was occurring due to tissue optical properties. The latter could be explained partly by differences in photosynthetic pigment content in the symbiont cells and pigmentation in the coral host tissue. Our results demonstrate that different strategies of light modulation at colony, polyp, and cellular levels by contrasting morphologies are equally effective in achieving favorable irradiances at the level of coral photosymbionts.

Mangrove dieback during fluctuating sea levels

Publisher: Springer Science and Business Media LLC

Date: 10-05-2017

DOI: 10.1038/S41598-017-01927-6

Abstract: Recent evidence indicates that climate change and intensification of the El Niño Southern Oscillation (ENSO) has increased variation in sea level. Although widespread impacts on intertidal ecosystems are anticipated to arise from the sea level seesaw associated with climate change, none have yet been demonstrated. Intertidal ecosystems, including mangrove forests are among those ecosystems that are highly vulnerable to sea level rise, but they may also be vulnerable to sea level variability and extreme low sea level events. During 16 years of monitoring of a mangrove forest in Mangrove Bay in north Western Australia, we documented two forest dieback events, the most recent one being coincident with the large-scale dieback of mangroves in the Gulf of Carpentaria in northern Australia. Diebacks in Mangrove Bay were coincident with periods of very low sea level, which were associated with increased soil salinization of 20–30% above pre-event levels, leading to canopy loss, reduced Normalized Difference Vegetation Index (NDVI) and reduced recruitment. Our study indicates that an intensification of ENSO will have negative effects on some mangrove forests in parts of the Indo-Pacific that will exacerbate other pressures.

Relationships among RNA DNA ratio, growth and elemental stoichiometry in mangrove trees

Publisher: Wiley

Date: 16-09-2010

DOI: 10.1111/J.1365-2435.2010.01722.X

Mangrove Systems and Environments☆

Publisher: Elsevier

Date: 2016

DOI: 10.1016/B978-0-12-409548-9.10262-3

The impact of a locust plague on mangroves of the arid Western Australia coast

Publisher: Cambridge University Press (CUP)

Date: 12-04-2012

DOI: 10.1017/S0266467412000041

Abstract: Mangroves generally grow in nutrient-poor environments and maintain high levels of productivity through unique adaptations for nutrient conservation (Reef et al . 2010). One such adaptation in mangroves is highly efficient resorption of limiting nutrients from senescing leaves prior to abscission (Feller et al . 2003). Thus processes that lead to loss of foliage prior to senescence and nutrient resorption (e.g. storms and herbivory) can be detrimental to tree growth and productivity (Bryant et al . 1983, May & Killingbeck 1992). Furthermore, decomposition of fallen leaves by soil microbial communities (Alongi 1994, Holguin et al . 2001) and crabs (Nagelkerken et al . 2008) is another important process contributing to the recycling of nutrients that are in short supply. Therefore, processes that lead to a substantial reduction in litterfall can have a strong negative effect on nutrient cycling and forest productivity. Mangroves have long been recognized as an important source of organic carbon (both particulate and dissolved) for the surrounding tropical coastal ecosystems (Bouillon et al . 2008, Kristensen et al . 2008). Thus, processes affecting litterfall in mangroves can affect the surrounding marine food webs.

Complex diel cycles of gene expression in coral-algal symbiosis

Publisher: American Association for the Advancement of Science (AAAS)

Date: 14-01-2011

DOI: 10.1126/SCIENCE.1196419

Abstract: Rhythmically expressed genes in reef-building corals may be required to deal with oxidative stress and the coral-algal symbiosis.

University Of Sydney

Location: Australia

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Monash University

Location: Australia

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Discovery Early Career Researcher Award - Grant ID: DE120101706

Start Date: 03-2012

End Date: 03-2015

Amount: $375,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE230100038

Start Date: 2023

End Date: 12-2024

Amount: $387,250.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP160100094

Start Date: 12-2016

End Date: 12-2020

Amount: $215,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP0666253

Start Date: 06-2006

End Date: 12-2009

Amount: $185,000.00

Funder: Australian Research Council

ARC Future Fellowships - Grant ID: FT170100153

Start Date: 11-2017

End Date: 11-2023

Amount: $948,232.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP110100472

Start Date: 2011

End Date: 11-2016

Amount: $564,539.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP0987614

Start Date: 01-2009

End Date: 04-2014

Amount: $320,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP180103444

Start Date: 08-2018

End Date: 10-2023

Amount: $323,415.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP220102873

Start Date: 04-2023

End Date: 03-2026

Amount: $335,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP160103669

Start Date: 06-2016

End Date: 12-2019

Amount: $413,500.00

Funder: Australian Research Council