Understanding leaf water isotope composition. This project aims to quantify variation in leaf water isotopes and develop mechanistic models for paleoclimatologists and plant scientists to constrain global carbon cycles. Leaf water stable isotopes influence the isotope compositions of atmospheric oxygen, carbon dioxide and water vapour, and impart an evaporative signal on the isotope composition of plant organic material. These isotope signals have been used to constrain global carbon and water c ....Understanding leaf water isotope composition. This project aims to quantify variation in leaf water isotopes and develop mechanistic models for paleoclimatologists and plant scientists to constrain global carbon cycles. Leaf water stable isotopes influence the isotope compositions of atmospheric oxygen, carbon dioxide and water vapour, and impart an evaporative signal on the isotope composition of plant organic material. These isotope signals have been used to constrain global carbon and water cycles and reconstruct past climates. This project aims to quantify variation in leaf water isotopes and develop mechanistic models for use by paleoclimatologists, plant scientists and to constrain global carbon cycles and develop accurate models of leaf water isotopes to reduce uncertainty in climate models.Read moreRead less
Understanding the mechanisms of thermal acclimation in the symbiotic algae (Symbiodinium) within cnidarian corals. Global warming is a major threat to coral reefs, contributing to devastating coral bleaching. This project will provide new insight into how coral reefs can respond to rising global temperature through clarifying the thermal acclimation mechanisms in corals using molecular techniques.
What limits CO2 diffusion inside leaves? Dissecting the diffusion path with Arabidopsis mutants. Human induced increase in atmospheric carbon dioxide is now generally accepted as contributing to global warming. Forecasting our future impact relies on models of terrestrial photosynthesis which use a signature in the atmosphere created by plants when they discriminate against the heavy stable isotope of carbon during photosynthesis. Discrimination between isotopes is affected by carbon dioxide dif ....What limits CO2 diffusion inside leaves? Dissecting the diffusion path with Arabidopsis mutants. Human induced increase in atmospheric carbon dioxide is now generally accepted as contributing to global warming. Forecasting our future impact relies on models of terrestrial photosynthesis which use a signature in the atmosphere created by plants when they discriminate against the heavy stable isotope of carbon during photosynthesis. Discrimination between isotopes is affected by carbon dioxide diffusion within leaves and key steps in this process will be identified through the use of Arabidopsis mutants. Better representation of this process in models will improve estimates of terrestrial photosynthesis and climate change forecastsRead moreRead less
Testing climatic, physiological and hydrological assumptions underpinning water yield from montane forests. Water collected in dams and reservoirs remains the mainstay water resource for Australian cities, towns and industry. Overwhelmingly, that water is collected from forested catchments where the water balance of forest stands is dominated by the amount of water used by trees. Characterising tree water use, its response to changing climatic and nocturnal conditions, and other aspects of sta ....Testing climatic, physiological and hydrological assumptions underpinning water yield from montane forests. Water collected in dams and reservoirs remains the mainstay water resource for Australian cities, towns and industry. Overwhelmingly, that water is collected from forested catchments where the water balance of forest stands is dominated by the amount of water used by trees. Characterising tree water use, its response to changing climatic and nocturnal conditions, and other aspects of stand hydrology, are crucial to our ability to predict and model future water yields. Working in the Cotter catchment near Canberra and the upper Kiewa catchment in north-east Victoria, we aim to help the agencies responsible for water and catchment management to improve the security of their forecasts of water yield and their on-ground management. Read moreRead less
Leaf respiration under drought: a global perspective. Predicting future net carbon exchange is necessary for better management of vegetation resources by Australia. Incorporating the responses of plant respiration to drought and temperature is crucial for predicting future rates of net carbon exchange. Using laboratory and field studies, this research will develop an understanding of how water availability and temperature impact on plant respiration of a broad range of economically important and ....Leaf respiration under drought: a global perspective. Predicting future net carbon exchange is necessary for better management of vegetation resources by Australia. Incorporating the responses of plant respiration to drought and temperature is crucial for predicting future rates of net carbon exchange. Using laboratory and field studies, this research will develop an understanding of how water availability and temperature impact on plant respiration of a broad range of economically important and ecologically relevant plant species. Equations will be formulated that will improve how modellers calculate drought-dependent variations in plant respiration (and thus plant productivity), thereby improving predictions for a future, warmer world.Read moreRead less
Oxygen isotope discrimination during C4 photosynthesis. Plants with the C4 photosynthetic pathway, like sugarcane and pasture grasses, are vital to Australian agriculture and natural ecosystems. This project will use novel laser spectroscopy to measure oxygen isotope discrimination during photosynthesis and quantify the influence of C4 plants on isotopic signatures of atmospheric CO2.
Out of the darkness: predicting rates of respiration of illuminated leaves along nutrient gradients. Our research will greatly assist in predictions of future net carbon exchange necessary if Australia is to better manage its vegetation resources. Crucial to predicting future rates of net carbon exchange is an understanding of how climate and nutrients impact on leaf respiration. Our research will develop an understanding of how light, temperature and phosphorus (the most widespread, limiting nu ....Out of the darkness: predicting rates of respiration of illuminated leaves along nutrient gradients. Our research will greatly assist in predictions of future net carbon exchange necessary if Australia is to better manage its vegetation resources. Crucial to predicting future rates of net carbon exchange is an understanding of how climate and nutrients impact on leaf respiration. Our research will develop an understanding of how light, temperature and phosphorus (the most widespread, limiting nutrient in Australia) impact on leaf respiration of a broad range of contrasting plants representative of several diverse Australian ecosystems. We will develop equations that will allow modellers to better predict climate/nutrient dependent variations in leaf respiration (and thus rates of plant productivity), both now and in the future.Read moreRead less
Climate dependence of plant respiration in a warmer, drier world. This research will greatly assist in predictions of future net carbon exchange that are necessary if Australia is to better manage its vegetation resources. Crucial to predicting future rates of net carbon exchange is an understanding of how drought and long-term changes in temperature impact on plant respiration. Using laboratory and field studies, this research will develop an understanding of how water availability and temperat ....Climate dependence of plant respiration in a warmer, drier world. This research will greatly assist in predictions of future net carbon exchange that are necessary if Australia is to better manage its vegetation resources. Crucial to predicting future rates of net carbon exchange is an understanding of how drought and long-term changes in temperature impact on plant respiration. Using laboratory and field studies, this research will develop an understanding of how water availability and temperature impact on plant respiration of a broad range of economically important and ecologically relevant plant species. Equations will be formulated that allow modellers to better predict drought-dependent variations in plant respiration (and thus plant productivity), both now and in a future, warmer world.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.
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.