Are subterranean estuaries a source or sink of greenhouse gases? The aim of this project is to investigate the role of subterranean estuaries and submarine groundwater discharge on the marine cycle of the greenhouse gases carbon dioxide, methane, and nitrous oxide. The expected outcome of this project is a better understanding of the role of coastal environments as a net source or sink of greenhouse gases.
Ocean-reef interactions as drivers of continental shelf productivity in a changing climate. Poor coastal management results in the irreparable destruction of reef systems' function and biodiversity, nationally and globally. To manage marine resources effectively we must implement sustainable practices, including forward planning in the context of climate change. A critical limitation in determining appropriate actions is a poor understanding of mechanisms driving productivity. Our project will p ....Ocean-reef interactions as drivers of continental shelf productivity in a changing climate. Poor coastal management results in the irreparable destruction of reef systems' function and biodiversity, nationally and globally. To manage marine resources effectively we must implement sustainable practices, including forward planning in the context of climate change. A critical limitation in determining appropriate actions is a poor understanding of mechanisms driving productivity. Our project will provide key information on the oceanographic mechanisms supporting Australia's coastal systems, linking nutrient supply, physical drivers and climate. By linking all these factors we will both assist in determining appropriate ecosystem management, and provide a knowledge base to support adaptation to future changes in Australia's climate.Read moreRead less
Unravelling the history of nitrogen cycling within the central Great Barrier Reef. This project aims to use coral skeleton geochemical analysis to establish if, when, and how nitrogen cycling changed along the central inshore region of the Great Barrier Reef (GBR) lagoon. Increasing anthropogenic nitrogen discharge to coastal waters could drive ecosystem decline in the GBR, one of Australia’s most sensitive and economically valuable natural environments. However, the full effect of anthropogenic ....Unravelling the history of nitrogen cycling within the central Great Barrier Reef. This project aims to use coral skeleton geochemical analysis to establish if, when, and how nitrogen cycling changed along the central inshore region of the Great Barrier Reef (GBR) lagoon. Increasing anthropogenic nitrogen discharge to coastal waters could drive ecosystem decline in the GBR, one of Australia’s most sensitive and economically valuable natural environments. However, the full effect of anthropogenic nitrogen is unclear due to a lack of long, continuous records. This project will unravel the history of nitrogen cycling in the GBR since the mid-1800s, knowledge crucial for managing this reef system.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
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
Factors influencing the bioavailability of iron in marine waters. Strong evidence now exists that iron availability controls the productivity and species composition of planktonic organisms in open oceans and coastal and estuarine environments. The mechanisms by which iron is rendered available and induces growth remain unclear but appear to involve, in many instances, light and both generic and specific organic complexants of iron. In this study, we investigate the effect of selected naturally ....Factors influencing the bioavailability of iron in marine waters. Strong evidence now exists that iron availability controls the productivity and species composition of planktonic organisms in open oceans and coastal and estuarine environments. The mechanisms by which iron is rendered available and induces growth remain unclear but appear to involve, in many instances, light and both generic and specific organic complexants of iron. In this study, we investigate the effect of selected naturally occurring complexants on redox transformations of iron with particular emphasis given to the potential ability of organics and light to increase the bioavailability of iron.Read moreRead less
Novel technologies to resolve the role of organic matter on iron chemistry and bioavailability in the South Pacific Ocean. This project promotes cross-disciplinary scientific collaborations at national and international levels to understand the role iron plays in regulating oceanic biodiversity, primary production and ability to mitigate climate change. This project will thus benefit to human society as a whole. New promising technologies will be developed to assess iron oceanic limitation, the ....Novel technologies to resolve the role of organic matter on iron chemistry and bioavailability in the South Pacific Ocean. This project promotes cross-disciplinary scientific collaborations at national and international levels to understand the role iron plays in regulating oceanic biodiversity, primary production and ability to mitigate climate change. This project will thus benefit to human society as a whole. New promising technologies will be developed to assess iron oceanic limitation, therefore fostering the international competitiveness of Australian research. This project will contribute to National Research Priority: Sustainable use of Australia's biodiversity. In addition, the proposed research is a vital element of global effort to advance our understanding of iron-related oceanic processes, as manifest in several international scientific programs.Read moreRead less
How iron is cycled in Southern Ocean waters. This project aims to probe the Southern Ocean phytoplankton’s ability to take up and retain iron, using iron isotope tracer techniques. The Southern Ocean regulates Earth's climate, but the supply of iron to Southern Ocean surface waters is low, restricting the ability of phytoplankton to flourish and draw down carbon dioxide. The results are expected to reveal survival strategies of phytoplankton in this iron-poor environment and their potential abil ....How iron is cycled in Southern Ocean waters. This project aims to probe the Southern Ocean phytoplankton’s ability to take up and retain iron, using iron isotope tracer techniques. The Southern Ocean regulates Earth's climate, but the supply of iron to Southern Ocean surface waters is low, restricting the ability of phytoplankton to flourish and draw down carbon dioxide. The results are expected to reveal survival strategies of phytoplankton in this iron-poor environment and their potential ability to adapt to environmental change. This knowledge could be used to develop models to manage this climate-sensitive region.Read moreRead less
An Investigation into Oceanic CO2 Variability and its Influence on Atmospheric CO2 Concentrations. Carbon dioxide is a powerful greenhouse gas whose observed atmospheric increase is the central cause
of climate change. The associated environmental, social and economic impacts to Australia could be
staggering via coral reef degradation, loss of agricultural production, coastal erosion and extreme climate
events. This work aims to better our understanding of how the oceans may mediate the effec ....An Investigation into Oceanic CO2 Variability and its Influence on Atmospheric CO2 Concentrations. Carbon dioxide is a powerful greenhouse gas whose observed atmospheric increase is the central cause
of climate change. The associated environmental, social and economic impacts to Australia could be
staggering via coral reef degradation, loss of agricultural production, coastal erosion and extreme climate
events. This work aims to better our understanding of how the oceans may mediate the effects of climate
change for Australia and therefore has a strong national benefit. Quantifying the importance Australia's
oceanic CO2 sink will be important for Australian policy makers within international climate negotiations
and also for better management practices to ensure the future prosperity of Australia's coral reef
ecosystem.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