Comparative eco-physiology of two contrasting arid-zone woodlands in Central Australia: hydrological niche separation and ecosystem resilience. This proposal addresses two fundamental questions: how do co-occurring species co-exist and why do Australian ecosystems have larger ecosystem water-use-efficiencies than those in the USA? This proposal will: determine the resilience of two contrasting arid-zone woodlands; compare variation in hydraulic-related plant traits across co-existing species; an ....Comparative eco-physiology of two contrasting arid-zone woodlands in Central Australia: hydrological niche separation and ecosystem resilience. This proposal addresses two fundamental questions: how do co-occurring species co-exist and why do Australian ecosystems have larger ecosystem water-use-efficiencies than those in the USA? This proposal will: determine the resilience of two contrasting arid-zone woodlands; compare variation in hydraulic-related plant traits across co-existing species; and, determine the relative contribution of changes in assimilation and stomatal conductance to variation (across species and time) in water-use-efficiency. Outcomes of this work include a mechanistic understanding of the behaviour of water-limited woodlands in current and future climates. This is significant because such biomes are globally important and are home to two billion people. Read moreRead less
Is water deficit the predisposing factor associated with Agonis flexuosa (WA peppermint) decline in Western Australia? The incidence and severity of tree decline across species is now widespread in southern Western Australia. There is increasing concern about their management by agencies, landowners and the community, due to the loss of aesthetics, biodiversity and ecosystem services. This project will provide remote sensing tools to monitor peppermint health and relate declines to abiotic and b ....Is water deficit the predisposing factor associated with Agonis flexuosa (WA peppermint) decline in Western Australia? The incidence and severity of tree decline across species is now widespread in southern Western Australia. There is increasing concern about their management by agencies, landowners and the community, due to the loss of aesthetics, biodiversity and ecosystem services. This project will provide remote sensing tools to monitor peppermint health and relate declines to abiotic and biotic factors. An understanding of how water abstraction for urban development and declining rainfall predispose trees to decline, and the application of thinning regimes, fungicides and nutrient implants will provide potential tools to the wider community that can be used to manage tree health.Read moreRead less
Advanced cryobanking for recalcitrant-seeded Australian rainforest plants. This project aims to develop an interdisciplinary research alliance to enhance the efficiency of ecological restoration for recalcitrant Australian rainforest plant species. The project expects to provide fundamental knowledge to target two major impediments to cryostorage of recalcitrant-seeded native species: desiccation sensitivity with relatively large size, and active metabolism and precocious germination. These attr ....Advanced cryobanking for recalcitrant-seeded Australian rainforest plants. This project aims to develop an interdisciplinary research alliance to enhance the efficiency of ecological restoration for recalcitrant Australian rainforest plant species. The project expects to provide fundamental knowledge to target two major impediments to cryostorage of recalcitrant-seeded native species: desiccation sensitivity with relatively large size, and active metabolism and precocious germination. These attributes severely limit the time available for effective use of collected germplasm for long-term storage. A combination of biochemical, biophysical and molecular simulation approaches will be used to optimise cryopreservation of a wide range of endangered Australian rainforest species. This should provide significant benefits such as enabling conservation agencies to greatly enhance their ability to preserve the unique Australian rainforest flora, particularly given current threats due to habitat loss and global warming.Read moreRead less
Unsaturation of vapour pressure inside leaves: fundamental, but unknown. This project aims to determine when and to what extent the air inside leaves becomes unsaturated with water vapour. All current interpretation and modelling of leaf gas exchange assumes saturation under all circumstances. Compelling evidence has been obtained that suggests this is not true under moderate air vapour pressure deficits. A novel technique will be employed to assess the water vapour concentration of the air insi ....Unsaturation of vapour pressure inside leaves: fundamental, but unknown. This project aims to determine when and to what extent the air inside leaves becomes unsaturated with water vapour. All current interpretation and modelling of leaf gas exchange assumes saturation under all circumstances. Compelling evidence has been obtained that suggests this is not true under moderate air vapour pressure deficits. A novel technique will be employed to assess the water vapour concentration of the air inside leaves based on stable isotope analysis of carbon dioxide and water vapour exchanged between leaves and air. The project is expected to provide fundamental knowledge about how stomata regulate photosynthesis and water use, with significant implications for modelling vegetation function and for improving the performance of crop plants.Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE120100518
Funder
Australian Research Council
Funding Amount
$375,000.00
Summary
Shifting rainfall from spring to autumn: tree growth and water use under climate change. Managing Australia's variable water resources is imperative. When the timing of rain shifts, with decreases in spring and increases in autumn, is water use in plants similar to plants which experience only a spring drought? Understanding plant water use as the timing of rain shifts will help us manage Australia's water more effectively.
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
Will stomatal responses to humidity and carbon dioxide constrain tropical forest productivity as atmospheric carbon dioxide rises? This project will investigate two physiological processes that will partly determine growth responses of tropical forest trees to rising atmospheric carbon dioxide. The project will produce equations summarising physiological responses that can be incorporated into process-based models of tropical forest productivity.
Reading the isotopic archive: carbon and oxygen stable isotope ratios as recorders of plant physiological processes. This project will investigate how plant physiological processes are reflected in stable isotope ratios of carbon and oxygen in plant tissues. Results will contribute towards a mechanistic understanding of the processes that cause isotopic modifications, thereby enabling an improved interpretation of naturally occurring stable isotope signals.
Disentangling climate and evolutionary controls over the temperature dependence of leaf respiration. The project will use field and laboratory studies to establish if there are systematic differences in the temperature responses of leaf respiration in plants adapted to hot and cold environments. The results will enable climate modellers to better predict impacts of climate change on carbon exchange between vegetation and the atmosphere.
A step change in modeling leaf respiration-photosynthesis relationships . This project aims to use innovative, high-throughput technologies to develop a novel framework that links daytime photosynthesis and starch/amino acid mobilisation to variations in night-time leaf respiration. Variations in leaf respiration can have large impacts on ecosystem functioning and the Earth’s climate. Although advances have been made in respiration modelling, current models are unable to predict dynamic, day-to- ....A step change in modeling leaf respiration-photosynthesis relationships . This project aims to use innovative, high-throughput technologies to develop a novel framework that links daytime photosynthesis and starch/amino acid mobilisation to variations in night-time leaf respiration. Variations in leaf respiration can have large impacts on ecosystem functioning and the Earth’s climate. Although advances have been made in respiration modelling, current models are unable to predict dynamic, day-to-day variations in respiratory rates. Expected outcomes include equations that predict daily variations in night-time leaf respiration for environments across Australia and overseas. Benefits to planners include the ability to more accurately model vegetation-atmosphere carbon exchange and future changes in climate. Read moreRead less