Pyrite: a deep-time capsule of ocean chemistry and atmosphere oxidation. Surprisingly little is known about trace element trends in past oceans, even though these data are vital for interpreting the evolution of the Earth's atmosphere, evolutionary pathways of marine life and cycles of major mineral deposits. Using laser-based analysis of sedimentary pyrite in deep marine rocks, this project aims to produce, for the first time, temporal variation curves for 25 trace elements in seawater over the ....Pyrite: a deep-time capsule of ocean chemistry and atmosphere oxidation. Surprisingly little is known about trace element trends in past oceans, even though these data are vital for interpreting the evolution of the Earth's atmosphere, evolutionary pathways of marine life and cycles of major mineral deposits. Using laser-based analysis of sedimentary pyrite in deep marine rocks, this project aims to produce, for the first time, temporal variation curves for 25 trace elements in seawater over the last 3.5 billion years. Preliminary research has validated the technique and demonstrated major changes in certain trace elements over geologically short periods. Outcomes will assist the minerals industry in the discovery of new deposits of zinc, copper, gold and iron ore in Australia.Read moreRead less
Iron sources and cycling in the Tasman Sea. Determining factors that influence the health and vitality of coastal and open-ocean regions is crucial to maintaining marine biodiversity and the Earth's climatic balance. This research project will determine the role iron plays in influencing phytoplankton growth, which ultimately regulates the drawdown of carbon dioxide by the oceans.
Past to future changes in ocean dynamics and biogeochemistry. This project aims to understand the impact of changes in ocean circulation on marine biogeochemistry, climate and ultimately the Antarctic ice-sheet by combining transient simulations of the last glacial cycle performed with an Earth system model incorporating the compilation of paleoproxy records. The oceanic circulation has varied over the last glacial cycle (~140,000 years) and is expected to change over the coming centuries due t ....Past to future changes in ocean dynamics and biogeochemistry. This project aims to understand the impact of changes in ocean circulation on marine biogeochemistry, climate and ultimately the Antarctic ice-sheet by combining transient simulations of the last glacial cycle performed with an Earth system model incorporating the compilation of paleoproxy records. The oceanic circulation has varied over the last glacial cycle (~140,000 years) and is expected to change over the coming centuries due to rising atmospheric carbon dioxide. The project will measure future changes in oceanic circulation on ocean acidification and oxygen content with a state-of-the-art high-resolution ocean carbon cycle model. This will lead to improved understanding of processes and feedbacks within the Earth system.Read moreRead less
Social networking in a changing ocean: Microbial-scale ecological interactions control ocean-scale chemistry. The function of the ocean is governed by microscopic organisms, including bacteria and phytoplankton. Oceanographers typically consider the ecology of these microbes across large ocean-scales, but their activities and interactions are defined at the scale of individual cells. This research will redefine our knowledge of important marine microbial processes by coupling novel physiologica ....Social networking in a changing ocean: Microbial-scale ecological interactions control ocean-scale chemistry. The function of the ocean is governed by microscopic organisms, including bacteria and phytoplankton. Oceanographers typically consider the ecology of these microbes across large ocean-scales, but their activities and interactions are defined at the scale of individual cells. This research will redefine our knowledge of important marine microbial processes by coupling novel physiological and molecular tools to resolve the microscale ecological links between bacteria and phytoplankton, and will identify how the chemical interactions between these groups change under shifting environmental conditions. This has significance for transforming our understanding of the factors that control the health and function of our important ocean ecosystems.Read moreRead less
Impact of Metal - Reactive Oxygen Species (ROS) Interactions on Growth and Toxicity of Ichthyotoxic Algae in Australian Coastal Waters. Toxic algal blooms in estuarine and coastal waters can have devastating economic and ecological impacts but remarkably little is known about the factors that control either organism growth or toxin severity. Recent studies suggest that the interplay between delivery of the nutrient trace metals iron and copper and the method via which the organism acts to assimi ....Impact of Metal - Reactive Oxygen Species (ROS) Interactions on Growth and Toxicity of Ichthyotoxic Algae in Australian Coastal Waters. Toxic algal blooms in estuarine and coastal waters can have devastating economic and ecological impacts but remarkably little is known about the factors that control either organism growth or toxin severity. Recent studies suggest that the interplay between delivery of the nutrient trace metals iron and copper and the method via which the organism acts to assimilate these metals is critical to the generation and aggressiveness of the toxins produced. These processes will be investigated in this study and conceptual and mathematical models will be developed which will assist in assessing management options for estuarine and coastal environments.Read moreRead less
Mechanisms of Iron Acquisition by the Cyanobacterium Trichodesmium in Coastal Waters. The toxic cyanobacterium Trichodesmium is the most conspicuous phytoplankter in Great Barrier Reef waters which, as a nitrogen fixer, produces and biologically packages "new" nitrogen into forms potentially available to other marine organisms and, as such, is likely to be a key driver of food web dynamics on the GBR. In this study, we will clarify the mechanism by which the critical nutrient iron is acquired by ....Mechanisms of Iron Acquisition by the Cyanobacterium Trichodesmium in Coastal Waters. The toxic cyanobacterium Trichodesmium is the most conspicuous phytoplankter in Great Barrier Reef waters which, as a nitrogen fixer, produces and biologically packages "new" nitrogen into forms potentially available to other marine organisms and, as such, is likely to be a key driver of food web dynamics on the GBR. In this study, we will clarify the mechanism by which the critical nutrient iron is acquired by this organism and, in so doing, assess the role that terrestrial activities play in iron supply.Read moreRead less
Microbe-produced repellents and their roles in marine pathogen behaviours. Economic losses caused by disease outbreaks in marine fisheries and aquaculture exceed US$6 billion per year globally. Decades of research in human and plant pathogens have revealed that the ability of pathogens to infect their host is governed by behaviours; however our understanding of the chemical cues affecting the behaviour of marine pathogens is very poor. This research program aims to combine new approaches in micr ....Microbe-produced repellents and their roles in marine pathogen behaviours. Economic losses caused by disease outbreaks in marine fisheries and aquaculture exceed US$6 billion per year globally. Decades of research in human and plant pathogens have revealed that the ability of pathogens to infect their host is governed by behaviours; however our understanding of the chemical cues affecting the behaviour of marine pathogens is very poor. This research program aims to combine new approaches in microfluidics and chemical imaging to identify the cues that govern the behaviour of marine pathogens. Expected outcomes include an improved capacity to predict, monitor and manage marine diseases, as well as novel strategies to prevent disease outbreaks, helping to protect Australia’s valuable marine estate.Read moreRead less
The Southern Ocean's response to abrupt climate change. This project aims to determine how the Southern Ocean responds to abrupt climate change, through geochemical analysis of marine sediment cores. Rapid warming events of the last ice age provide an analogue to human-caused warming. Experiments using ocean climate models will evaluate the drivers and consequences of the biogeochemical response of different sectors and zones of the Southern Ocean. The intended outcome is a better understanding ....The Southern Ocean's response to abrupt climate change. This project aims to determine how the Southern Ocean responds to abrupt climate change, through geochemical analysis of marine sediment cores. Rapid warming events of the last ice age provide an analogue to human-caused warming. Experiments using ocean climate models will evaluate the drivers and consequences of the biogeochemical response of different sectors and zones of the Southern Ocean. The intended outcome is a better understanding of how and why climate change impacts ocean productivity in the ecologically significant Southern Ocean. This will lead to better representations of carbon feedbacks in climate models and more robust projections of future climate change.Read moreRead less
Changes in the ocean's biological pump: innovative models and diagnostics. This Project aims to quantify how the ocean’s biological pump, which exports newly formed organic matter into the ocean interior, responds to environmental change. The biological pump is a key control on the global carbon and oxygen cycles, and hence on the viability of marine life. New, efficient numerical models will be developed and analysed with highly innovative mathematical methods. Expected outcomes are optimised .... Changes in the ocean's biological pump: innovative models and diagnostics. This Project aims to quantify how the ocean’s biological pump, which exports newly formed organic matter into the ocean interior, responds to environmental change. The biological pump is a key control on the global carbon and oxygen cycles, and hence on the viability of marine life. New, efficient numerical models will be developed and analysed with highly innovative mathematical methods. Expected outcomes are optimised predictive models and a new understanding of the possible future evolutions of the ocean carbon cycle, acidification, and oxygenation. This should provide significant benefits such as predictions of future ocean health, identification of processes that are sensitive to change, and strategies for marine resource management.Read moreRead less
Global ocean productivity: revealing interaction patterns and nutrient pathways. This project will reveal how the nutrient supply of a given region of the ocean can strongly influence biological productivity at great distances because of long-range oceanic nutrient transport. This has important implications for global-scale resource management, such as the artificial fertilisation of the ocean for climate-change mitigation.