Brown is the new green: grassland responses to drought and heat. This project aims to improve accuracy and precision in predicting the impact of water availability and heat stress on grassland function. Grassland ecosystems are important reservoirs of global biodiversity and carbon storage. Grasslands are highly sensitive to drought and heat stress, but studies recently showed that current grassland models cannot predict these responses because they do not adequately represent the key processes ....Brown is the new green: grassland responses to drought and heat. This project aims to improve accuracy and precision in predicting the impact of water availability and heat stress on grassland function. Grassland ecosystems are important reservoirs of global biodiversity and carbon storage. Grasslands are highly sensitive to drought and heat stress, but studies recently showed that current grassland models cannot predict these responses because they do not adequately represent the key processes of physiological drought tolerance, leaf browning, and species traits. This project will collect targeted data sets in order to develop and test model representations of these key processes. This will provide significant benefits, such as greatly increasing capacity to predict the impact of drought and heat stress on grasslands, at scales ranging from field to globe.Read moreRead less
Temperature sensitivity of soil respiration and its components. This project aims to demonstrate how temperate evergreen forests could buffer against climate change. Soil respiration returns around half the carbon taken up by forests to the atmosphere. This project will characterise and quantify how microbes and roots in soils depend on temperature and substrate supply, and so predict how rising temperatures and drought will affect forests as natural carbon sequestration sinks. This project will ....Temperature sensitivity of soil respiration and its components. This project aims to demonstrate how temperate evergreen forests could buffer against climate change. Soil respiration returns around half the carbon taken up by forests to the atmosphere. This project will characterise and quantify how microbes and roots in soils depend on temperature and substrate supply, and so predict how rising temperatures and drought will affect forests as natural carbon sequestration sinks. This project will resolve the roles of environmental drivers of soil respiration across forests; integrate mechanistic understanding of differing plant and microbial responses to temperature within a common modelling framework; and evaluate the implications of this knowledge in predictions of climatic impacts on terrestrial carbon cycling.Read moreRead less
Woodland response to elevated CO2 in free air carbon dioxide enrichment: does phosphorus limit the sink for Carbon? This project will determine if growth of Australian woodland trees is limited by phosphorus, and if that limitation means the woodland carbon sink is constrained from responding to rising atmospheric CO2. Assessing the CO2 sink capacity of native eucalypt woodland is central to meeting Australia's domestic and international carbon accounting commitments.
Silicon defences for plant protection. This project aims to study how silicon uptake in grasses affects plant susceptibility aboveground. Grasses contain more silicon than nearly any other plant, which they acquire entirely from the soil. Silicon increases plant resistance to herbivores, disease and drought, but up to 25 per cent of grass productivity is lost to root herbivores, a situation compounded by water stress. Silicon uptake is poorly understood, but root herbivory and changing rainfall ....Silicon defences for plant protection. This project aims to study how silicon uptake in grasses affects plant susceptibility aboveground. Grasses contain more silicon than nearly any other plant, which they acquire entirely from the soil. Silicon increases plant resistance to herbivores, disease and drought, but up to 25 per cent of grass productivity is lost to root herbivores, a situation compounded by water stress. Silicon uptake is poorly understood, but root herbivory and changing rainfall patterns can either impair uptake or induce the plant to take up more silicon. The goal of this project is to optimise silicon-based resistance in grasses and exploit this for plant protection from invasive pests and drought.Read moreRead less
The failure-threshold of leaves in drought. This project aims to reveal how specific water-stress thresholds damage the leaves of Australian crop and forest species during drought. Water stress affects agricultural productivity and plant survival in drought-prone regions such as Australia. Using optical and X-ray techniques, this project seeks to visualise and quantify the dynamic processes of damage and repair in leaves under stress. Anticipated outputs include a practical basis to predict drou ....The failure-threshold of leaves in drought. This project aims to reveal how specific water-stress thresholds damage the leaves of Australian crop and forest species during drought. Water stress affects agricultural productivity and plant survival in drought-prone regions such as Australia. Using optical and X-ray techniques, this project seeks to visualise and quantify the dynamic processes of damage and repair in leaves under stress. Anticipated outputs include a practical basis to predict drought-induced canopy death; identification of threats to ecologically sensitive plants; and selection and screening tools to improve the drought resilience of agriculturally important crop species.Read moreRead less
Diatom silica production under future ocean conditions, genes to biomes. This project aims to quantify how ocean warming and acidification will alter natural diatom assemblages and silica production rates to predict changes in the cycling and transfer of carbon and silicon in the future ocean. This project expects to generate new knowledge of environmental controls on diatom silicification and their ocean-scale implications by integrating the disciplines of physiology, molecular biology and quan ....Diatom silica production under future ocean conditions, genes to biomes. This project aims to quantify how ocean warming and acidification will alter natural diatom assemblages and silica production rates to predict changes in the cycling and transfer of carbon and silicon in the future ocean. This project expects to generate new knowledge of environmental controls on diatom silicification and their ocean-scale implications by integrating the disciplines of physiology, molecular biology and quantitative modelling. Expected outcomes include essential advancements in future simulations of marine productivity and silicon cycling and a deeper understanding of threats to marine life from climate change. This should provide significant benefits such as improved valuations on the sustainability of ocean ecosystems.Read moreRead less
Understanding the survival of forests under drought . Droughts are predicted to become more extreme in the near future, with potentially devastating impacts on Australian forest ecosystems. This project aims to address key knowledge gaps in our understanding of how plants tolerate extreme drought stress and utilise this new knowledge to improve vegetation models suitable for assessing ecosystem vulnerability. We will use innovative experimental methodology to determine the processes by which wat ....Understanding the survival of forests under drought . Droughts are predicted to become more extreme in the near future, with potentially devastating impacts on Australian forest ecosystems. This project aims to address key knowledge gaps in our understanding of how plants tolerate extreme drought stress and utilise this new knowledge to improve vegetation models suitable for assessing ecosystem vulnerability. We will use innovative experimental methodology to determine the processes by which water transport breaks down in roots, stems and leaves and the mechanisms governing recovery from severe drought stress. The project will provide a deeper understanding of drought tolerance in trees, improved forecasting of risks to native vegetation, and enhanced management of native forest resources. Read moreRead less
Diagnosing coral health tipping points under accelerating coastal hypoxia. This project aims to unlock the role hypoxia plays in shaping the healthy functioning of corals over space and time. Climate change and land use development are rapidly deoxygenating shallow water coral reefs and amplifying hypoxia exposure, yet we have no knowledge of the oxygen thresholds that sustain ‘normal’ coral functioning, or the mechanisms corals’ employ to tolerate hypoxia. This project will couple advanced oxyg ....Diagnosing coral health tipping points under accelerating coastal hypoxia. This project aims to unlock the role hypoxia plays in shaping the healthy functioning of corals over space and time. Climate change and land use development are rapidly deoxygenating shallow water coral reefs and amplifying hypoxia exposure, yet we have no knowledge of the oxygen thresholds that sustain ‘normal’ coral functioning, or the mechanisms corals’ employ to tolerate hypoxia. This project will couple advanced oxygen sensing, metabolic physiology and functional genomics techniques to transform our understanding of how corals and their associated microbial communities respond to reduced oxygen conditions, which is essential to improve coral reef ecosystem management.Read moreRead less
Pushing the envelope: does range size limit eucalypt tolerance to warming? This project aims to characterise the biogeographic constraints on the physiological flexibility of eucalypts to accommodate climate warming. Do temperature tolerances of diverse taxa vary predictably with native geographic range sizes and climate of origin? In addressing this question, the project expects to generate new knowledge on the comparative physiological responses of diverse eucalypt taxa to warming and heat wav ....Pushing the envelope: does range size limit eucalypt tolerance to warming? This project aims to characterise the biogeographic constraints on the physiological flexibility of eucalypts to accommodate climate warming. Do temperature tolerances of diverse taxa vary predictably with native geographic range sizes and climate of origin? In addressing this question, the project expects to generate new knowledge on the comparative physiological responses of diverse eucalypt taxa to warming and heat waves using controlled-environment studies and a unique facility at Western Sydney University for heat wave studies of large trees. Expected outcomes include an enhanced capacity to predict carbon exchange and growth responses of native trees to climate warming over large geographic scales.Read moreRead less
Turning water into carbon: a synthesis of plant water-use efficiency from leaf to globe. The efficiency with which plants use water to gain carbon is a fundamental aspect of plant growth that has been frequently measured but is poorly understood. Using our new theory to draw together major datasets, the project will make a dramatic advance in our ability to understand and predict this key aspect of ecosystem function.