Testing the Flood Pulse Concept for rivers with variable flow regimes. For floodplain rivers the major unifying conceptual model linking hydrology, biogeochemistry and ecology is the Flood Pulse Concept (FPC). The model is based on rivers that have a seasonally predictable and long duration inundation of floodplain habitats. Recent reviews of the FPC indicate that the model needs to be broadened to describe the function of rivers with more variable flow regimes. This project will test some of th ....Testing the Flood Pulse Concept for rivers with variable flow regimes. For floodplain rivers the major unifying conceptual model linking hydrology, biogeochemistry and ecology is the Flood Pulse Concept (FPC). The model is based on rivers that have a seasonally predictable and long duration inundation of floodplain habitats. Recent reviews of the FPC indicate that the model needs to be broadened to describe the function of rivers with more variable flow regimes. This project will test some of the predictions of the FPC for variable dryland rivers by investigating how food webs in the channels of a floodplain reach respond to flows of different magnitude, seasonal timing and duration.Read moreRead less
Will trees get enough nitrogen to sustain productivity in elevated CO2? The project proposes to explore how tissue nitrogen declines in future elevated carbon dioxide (eCO2) by studying the availability of soil nitrogen to plants and use of nitrogen by Eucalyptus woodland trees. Plant canopy nitrogen concentrations decline in nearly every large-scale eCO2 study done on native soils. The project plans to explore how changes in ecosystem nitrogen balance occur, by investigating if leaf nitrogen de ....Will trees get enough nitrogen to sustain productivity in elevated CO2? The project proposes to explore how tissue nitrogen declines in future elevated carbon dioxide (eCO2) by studying the availability of soil nitrogen to plants and use of nitrogen by Eucalyptus woodland trees. Plant canopy nitrogen concentrations decline in nearly every large-scale eCO2 study done on native soils. The project plans to explore how changes in ecosystem nitrogen balance occur, by investigating if leaf nitrogen declines under eCO2 due to the balance of plant activity versus changes in soil nitrogen availability. The outcomes are central to knowing the extent to which extra nitrogen ‘feeds’ the eCO2 fertilisation response and sustains long-term increases in productivity. Expected outcomes may support the development of management options to sustain future forest productivity.Read moreRead less
A general theory for ecological trait-strategy dimensions. This project aims to bridge the gap in understanding of ecological strategies between plant and animal ecology, globally, using ants. It will test how environmental change influences the success of species, based on ecological strategies, and the consequences for ecosystem function. This project is expected to make a significant contribution to generality and prediction in ecology. Expected outcomes of this project include theory deve ....A general theory for ecological trait-strategy dimensions. This project aims to bridge the gap in understanding of ecological strategies between plant and animal ecology, globally, using ants. It will test how environmental change influences the success of species, based on ecological strategies, and the consequences for ecosystem function. This project is expected to make a significant contribution to generality and prediction in ecology. Expected outcomes of this project include theory development and application and enhanced global networks of trait researchers. Intended benefits include improved ecological theory, an enhanced capacity to predict how global change will affect organisms and increased understanding of the cascading effects of changes for ecosystem function.Read moreRead less
Tree-mediated methane fluxes: A new frontier in the global carbon cycle. Methane is an extremely potent greenhouse gas. Recent evidence suggests that tree-mediated fluxes may be a significant, but overlooked source of methane to the atmosphere. This project aims to quantify the magnitude and drivers of tree-mediated methane fluxes from Australia’s dominant forest types. Innovatively, we will be using a novel combination of empirical field based measurements, gas tracer experiments, microbial ana ....Tree-mediated methane fluxes: A new frontier in the global carbon cycle. Methane is an extremely potent greenhouse gas. Recent evidence suggests that tree-mediated fluxes may be a significant, but overlooked source of methane to the atmosphere. This project aims to quantify the magnitude and drivers of tree-mediated methane fluxes from Australia’s dominant forest types. Innovatively, we will be using a novel combination of empirical field based measurements, gas tracer experiments, microbial analysis and modelling methods. Expected outcomes are a mechanistic understanding of tree-mediated methane fluxes, helping to constrain regional, national and global methane budgets. The results of this study will help inform publicly funded greenhouse gas abatement strategies, ensuring a maximal return on investment.Read moreRead less
To grow or to store: Do plants hedge their bets? This project aims to resolve a long-standing question about the function of perennial plants: how much of the carbon taken up by photosynthesis is used immediately for growth, and how much is kept in reserve as insurance against future stress? This question is important to our understanding of how plants respond to stresses such as severe drought, and yet lack of data and theoretical modelling currently hampers our ability to answer it. By applyin ....To grow or to store: Do plants hedge their bets? This project aims to resolve a long-standing question about the function of perennial plants: how much of the carbon taken up by photosynthesis is used immediately for growth, and how much is kept in reserve as insurance against future stress? This question is important to our understanding of how plants respond to stresses such as severe drought, and yet lack of data and theoretical modelling currently hampers our ability to answer it. By applying novel data analysis and modelling tools to recent experimental results, the project plans to test hypotheses for how plants allocate carbon between growth and storage in response to stress. Insights from the project may underpin better management of Australia’s vulnerable ecosystems.Read moreRead less
Mechanistic responses of phosphorus-limited forests to CO2 enrichment. Carbon dioxide continues to accumulate in the atmosphere, driven by human emissions. The future fate of the global forest carbon sink, which significantly slows CO2 increase in the atmosphere, helping to dampen climate change, remains poorly constrained, hindering mitigation and adaptation planning. A key gap concerns the role of phosphorus, crucial in limiting the productivity of Australian woodlands and tropical forests. Mo ....Mechanistic responses of phosphorus-limited forests to CO2 enrichment. Carbon dioxide continues to accumulate in the atmosphere, driven by human emissions. The future fate of the global forest carbon sink, which significantly slows CO2 increase in the atmosphere, helping to dampen climate change, remains poorly constrained, hindering mitigation and adaptation planning. A key gap concerns the role of phosphorus, crucial in limiting the productivity of Australian woodlands and tropical forests. Model-data fusion based on the results of a crossed CO2 x P experiment in Eucalyptus forest - EucFACE - will help close this vital knowledge gap, and leverage new mechanistic knowledge in a leading global model used for climate and emissions assessment.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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Linking phytoplankton to fisheries using zooplankton size spectra. This project aims to develop innovative numerical methods to understand the dynamics, carbon export, and trophic structure of zooplankton. The trophic links between phytoplankton, zooplankton and fisheries are unknown. The size- frequency distribution of zooplankton (size spectrum) is an innovative method for estimating their growth, predation and production as food for fish. Analysis of a global synthesis of zooplankton size dis ....Linking phytoplankton to fisheries using zooplankton size spectra. This project aims to develop innovative numerical methods to understand the dynamics, carbon export, and trophic structure of zooplankton. The trophic links between phytoplankton, zooplankton and fisheries are unknown. The size- frequency distribution of zooplankton (size spectrum) is an innovative method for estimating their growth, predation and production as food for fish. Analysis of a global synthesis of zooplankton size distributions from tropical to polar environments are expected to reveal these vital rates of pelagic ecosystems. The zooplankton rates will reveal, for the first time, the link between phytoplankton and fisheries, and will significantly improve ecosystem models and global assessments of environmental change.Read moreRead less
Size matters: evolution of body size of species in deep time. Global warming is predicted to form 'sick seas' and cause widespread stunted growth of taxa and ecosystem-wide dwarfism. Exactly how this works requires substantiation of both short-term empirical and experimental research as well as evidence from the deep-time fossil record. Using the high-resolution marine fossil record from the Permian-Triassic mass extinction ~252 million years ago, the most severe in the history of animals, this ....Size matters: evolution of body size of species in deep time. Global warming is predicted to form 'sick seas' and cause widespread stunted growth of taxa and ecosystem-wide dwarfism. Exactly how this works requires substantiation of both short-term empirical and experimental research as well as evidence from the deep-time fossil record. Using the high-resolution marine fossil record from the Permian-Triassic mass extinction ~252 million years ago, the most severe in the history of animals, this project will investigate how body size of marine species and communities evolved in response to the mass extinction and rapid global warming. It is expected that the project findings will help better understand the links between global warming, anoxia, hypercapnia, euxinia, ocean acidification, and species adaptation and evolution.Read moreRead less
Avoiding coral bleaching: investigation into the repair of damaged photosynthetic machinery in symbiotic algae (symbiodinium) within corals. Photosynthesis in symbiotic algae within corals is essential for a healthy alga-coral symbiotic relationship. This project will provide new insights into how symbiotic algae maintain higher photosynthetic performance in corals through elucidating the mechanism associated with the repair of photodamaged photosynthetic machinery.