New perspectives on arsenic speciation and fate in anoxic aqueous environments: Resolving unexplored interactions with the sulfur cycle. Using exciting new experiments and innovative analyses, this project will provide transformational insights into how sulfur cycling in the Earth’s critical zone affects arsenic speciation and fate. The project will resolve, for the first time, unexplored interactions between arsenic geochemistry and the low-temperature formation and transformation of metastable ....New perspectives on arsenic speciation and fate in anoxic aqueous environments: Resolving unexplored interactions with the sulfur cycle. Using exciting new experiments and innovative analyses, this project will provide transformational insights into how sulfur cycling in the Earth’s critical zone affects arsenic speciation and fate. The project will resolve, for the first time, unexplored interactions between arsenic geochemistry and the low-temperature formation and transformation of metastable iron sulfide minerals. The outcomes will provide crucially important new perspectives on arsenic geochemistry in anoxic soils, sediments and groundwater systems.Read moreRead less
Interactions between antimony and the sulphur cycle. This project aims to unravel unexplored interactions between the sulphur cycle and fundamentally important aspects of antimony geochemistry in the Earth’s critical zone. This project will resolve interactions between antimony geochemistry and the low-temperature formation and transformation of metastable iron sulphide minerals. The outcomes are expected to provide crucially important perspectives on antimony geochemistry in anoxic soils, sedim ....Interactions between antimony and the sulphur cycle. This project aims to unravel unexplored interactions between the sulphur cycle and fundamentally important aspects of antimony geochemistry in the Earth’s critical zone. This project will resolve interactions between antimony geochemistry and the low-temperature formation and transformation of metastable iron sulphide minerals. The outcomes are expected to provide crucially important perspectives on antimony geochemistry in anoxic soils, sediments and groundwater systems. This understanding should lead to more accurate geochemical risk assessments and better site treatment strategies for environmental antimony contamination.Read moreRead less
Reactive oxygen species production on oxygenation of subsurface sediments. This project aims to examine the nature, extent and effect of redox processes in subsurface environments. Reactive oxygen species, including hydrogen peroxide, superoxide and hydroxyl radicals, transform and affect redox-active substances in the environment such as arsenic, uranium and natural organic matter (which may be oxidised to carbon dioxide). Production of significant quantities of reactive oxygen species on oxyge ....Reactive oxygen species production on oxygenation of subsurface sediments. This project aims to examine the nature, extent and effect of redox processes in subsurface environments. Reactive oxygen species, including hydrogen peroxide, superoxide and hydroxyl radicals, transform and affect redox-active substances in the environment such as arsenic, uranium and natural organic matter (which may be oxidised to carbon dioxide). Production of significant quantities of reactive oxygen species on oxygenation of subsurface sediments through actions such as aquifer recharge and high flow events may alter the form and mobility of trace elements and influence the cycling of carbon and eventual efflux of carbon dioxide to the atmosphere. This project will examine the nature, extent and effect of these redox processes in selected subsurface environments. This research could have implications for contaminant transformation and fate and carbon cycling.Read moreRead less
Resolving the geochemistry of coastal floodplain blackwaters. Deoxygenated dead zones are a rapidly growing global crisis in coastal areas. A major cause of dead zones in our estuaries is the formation and release of blackwaters from coastal wetlands. This project will provide the knowledge necessary to manage blackwaters in these wetlands and to greatly improve the health and sustainability of our estuaries.
Redox transformations of natural organic matter. This project aims to determine the electron transfer (redox) properties of terrestrially and microbially-derived natural organic matter (NOM) and the implications of these redox characteristics to reactive oxygen species generation, metals transformation and carbon cycling. Experimental and computational studies using model compounds containing quinone and thiol-containing functional groups as well as well-characterised humic substances and algal ....Redox transformations of natural organic matter. This project aims to determine the electron transfer (redox) properties of terrestrially and microbially-derived natural organic matter (NOM) and the implications of these redox characteristics to reactive oxygen species generation, metals transformation and carbon cycling. Experimental and computational studies using model compounds containing quinone and thiol-containing functional groups as well as well-characterised humic substances and algal exudates will be undertaken under both dark and light conditions. Kinetic models of these processes will be developed enabling prediction of the impact of NOM-mediated electron transfer processes on oxidant generation, metals transformation and carbon cycling.Read moreRead less
Untangling metabolism and greenhouse gas production in intermittent streams. Freshwater streams are disproportionately large producers of greenhouse gases. Identifying the factors controlling their greenhouse gas production is critical as stream function is increasingly altered by both changing rainfall patterns and human pollution. This project aims to resolve the factors controlling stream greenhouse gas production. It will apply an unprecedented combination of continuous stream function and i ....Untangling metabolism and greenhouse gas production in intermittent streams. Freshwater streams are disproportionately large producers of greenhouse gases. Identifying the factors controlling their greenhouse gas production is critical as stream function is increasingly altered by both changing rainfall patterns and human pollution. This project aims to resolve the factors controlling stream greenhouse gas production. It will apply an unprecedented combination of continuous stream function and intensive isotope measurements to perennially flowing and intermittent streams in disturbed and undisturbed landscapes. This project is significant because it will quantify the changing role of streams in greenhouse gas emissions. Outcomes will provide critical information for managing Australia’s freshwater resources. Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE150100500
Funder
Australian Research Council
Funding Amount
$321,000.00
Summary
Electron transfer at the microbe-mineral interface via cytochromes/exudates. This project aims to develop the kinetic (both in vivo and in vitro) and thermodynamic models of the extracellular electron transfer processes at the microbe-mineral interface via outer membrane cytochromes and exudates of dissimilatory iron-reducing bacteria, and elucidating the potential electron transfer process from iron-reducing bacteria to semiconducting iron minerals. The observed models will provide a more compr ....Electron transfer at the microbe-mineral interface via cytochromes/exudates. This project aims to develop the kinetic (both in vivo and in vitro) and thermodynamic models of the extracellular electron transfer processes at the microbe-mineral interface via outer membrane cytochromes and exudates of dissimilatory iron-reducing bacteria, and elucidating the potential electron transfer process from iron-reducing bacteria to semiconducting iron minerals. The observed models will provide a more comprehensive understanding of electron transfer reactions at the microbe-mineral interface, which will be helpful in the prediction of natural redox processes of iron transformation and in the development of bioremediation strategies for contaminated sites.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE150100007
Funder
Australian Research Council
Funding Amount
$170,000.00
Summary
Metal speciation for complex studies in changing environments. Metal speciation for complex studies in changing environments: The Inductively Coupled Plasma Mass Spectrometer with a High Performance Liquid Chromatography front end (HPLC-ICP-MS) for metal speciation studies is a highly valuable extension of existing cutting edge infrastructure for geochemical research. Existing invertebrate culturing capacity will also enable unique opportunities for experimental studies driven by understanding m ....Metal speciation for complex studies in changing environments. Metal speciation for complex studies in changing environments: The Inductively Coupled Plasma Mass Spectrometer with a High Performance Liquid Chromatography front end (HPLC-ICP-MS) for metal speciation studies is a highly valuable extension of existing cutting edge infrastructure for geochemical research. Existing invertebrate culturing capacity will also enable unique opportunities for experimental studies driven by understanding metal speciation and uptake by organisms. This facility will be housed within a highly productive research environment providing new and novel capabilities to study abiotic and biotic interactions in changing environments.Read moreRead less
Shallow water carbonate sediment dissolution in the global carbon cycle. Carbonate sediment dissolution is a globally significant process, but poorly understood in shallow marine waters. This project will determine whether the combined effect of organic matter, ocean acidification and pore water flow in shallow water carbonate sediments increases the release of calcium and alkalinity to the ocean. This project is significant because this release has not previously been accounted for and may lead ....Shallow water carbonate sediment dissolution in the global carbon cycle. Carbonate sediment dissolution is a globally significant process, but poorly understood in shallow marine waters. This project will determine whether the combined effect of organic matter, ocean acidification and pore water flow in shallow water carbonate sediments increases the release of calcium and alkalinity to the ocean. This project is significant because this release has not previously been accounted for and may lead to an additional uptake of atmospheric carbon dioxide into the global ocean, maybe some additional buffering against ocean acidification, but unfortunately, maybe also a loss of carbonate ecosystems. The outcomes of this project will make a significant contribution to our understanding of the global carbon cycle.
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Discovery Early Career Researcher Award - Grant ID: DE150100770
Funder
Australian Research Council
Funding Amount
$358,536.00
Summary
Solving the mystery of natural carbon mineralisation in Australian lakes. Some lakes, such as the Coorong lakes in South Australia, naturally sequester carbon dioxide in magnesium carbonate minerals. These minerals, which form in association with microorganisms in lake water, represent the safest possible long-term traps for carbon dioxide pollution. This project aims to determine the essential geochemical constraints on formation of magnesium carbonate minerals in the Coorong lakes, which are u ....Solving the mystery of natural carbon mineralisation in Australian lakes. Some lakes, such as the Coorong lakes in South Australia, naturally sequester carbon dioxide in magnesium carbonate minerals. These minerals, which form in association with microorganisms in lake water, represent the safest possible long-term traps for carbon dioxide pollution. This project aims to determine the essential geochemical constraints on formation of magnesium carbonate minerals in the Coorong lakes, which are unique natural laboratories for studying carbon dioxide sequestration. By delivering fundamental understanding of how microbial populations alter water chemistry for carbonate production, this project aims to inform the design of efficient and sustainable technologies for carbon dioxide sequestration that emulate natural processes in lakes.Read moreRead less