Eucalypt growth in past and future environments - a novel approach to understanding the impacts of atmospheric CO2 and climate. The impact of climate change and rising atmospheric CO2 on Australia's plantation and native forests is a major concern for government and land managers. These forests are important for environmental, aesthetic, and economic purposes, including carbon sequestration and trading. Forests use large amounts of water, reducing stream flow and water supplies for rural and u ....Eucalypt growth in past and future environments - a novel approach to understanding the impacts of atmospheric CO2 and climate. The impact of climate change and rising atmospheric CO2 on Australia's plantation and native forests is a major concern for government and land managers. These forests are important for environmental, aesthetic, and economic purposes, including carbon sequestration and trading. Forests use large amounts of water, reducing stream flow and water supplies for rural and urban communities. Knowledge generated from the proposed project will provide insight into mechanisms driving productivity and water use of forests in current and future environments. The knowledge will be used by land managers and government to develop strategies to cope with future impacts of climate change.Read 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
Elevated carbon dioxide (CO2) effects on vegetation: repairing the disconnect between experiments and models. Ecosystem models are important tools used in a variety of applications, including predicting how vegetation uptake of carbon affects global climate, estimating carbon sequestration by natural and planted forests and determining water yield of catchments. Although there has been a massive investment in experiments to determine plant response to elevated carbon dioxide [CO2], ecosystem mod ....Elevated carbon dioxide (CO2) effects on vegetation: repairing the disconnect between experiments and models. Ecosystem models are important tools used in a variety of applications, including predicting how vegetation uptake of carbon affects global climate, estimating carbon sequestration by natural and planted forests and determining water yield of catchments. Although there has been a massive investment in experiments to determine plant response to elevated carbon dioxide [CO2], ecosystem models do not incorporate this body of data as well as they could. This project will use innovative methods to bridge the gap between experimental data and ecosystem models, resulting in significantly improved information for managers of Australia's natural resources into the future.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
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
Tolerance of temperature extremes under drought: linking physiological processes with morphological constraints on leaf function. Freezing temperatures affect over 70% of Australia. Each year frosts cause substantial damage to agriculture and forestry. We will examine how decrease in hydraulic conduit diameter increases freeze tolerance in native woody species and quantify impacts of this tolerance on productivity of leaves. The results have application in managing temperate woody vegetation un ....Tolerance of temperature extremes under drought: linking physiological processes with morphological constraints on leaf function. Freezing temperatures affect over 70% of Australia. Each year frosts cause substantial damage to agriculture and forestry. We will examine how decrease in hydraulic conduit diameter increases freeze tolerance in native woody species and quantify impacts of this tolerance on productivity of leaves. The results have application in managing temperate woody vegetation under current and future climate scenarios. By improving understanding of the behaviour of water in leaves during freezing, we will contribute to improved models of physical stresses and strains in biological tissues during freezing, which find application in cryo-storage of biological materials important in agriculture, medicine, and conservation.Read moreRead less
Effects of global climate change on marine phytoplankton: interactions between UV radiation and elevated atmospheric carbon dioxide levels. Global climate change is one of the most significant ecological challenges for the 21st Century. Phytoplankton contribute over 45% of the planet's annual net primary production and form the basis of most aquatic food chains. Conversely, some phytoplankton are toxic and cause problems in marine and fresh waters. Climate change can potentially disrupt aquatic ....Effects of global climate change on marine phytoplankton: interactions between UV radiation and elevated atmospheric carbon dioxide levels. Global climate change is one of the most significant ecological challenges for the 21st Century. Phytoplankton contribute over 45% of the planet's annual net primary production and form the basis of most aquatic food chains. Conversely, some phytoplankton are toxic and cause problems in marine and fresh waters. Climate change can potentially disrupt aquatic foodchains by its impact on primary production by phytoplankton or stimulating growth of potentially toxic forms. Our project will investigate the combined impact of increasing carbon dioxide and ultraviolet light on phytoplankton and thereby help climate modellers assess the impact of climate change on aquatic ecosystems and particularly on the nation's and the world's fisheries.Read moreRead less
Ecophysiological limitations that affect water and carbon balance within large tree canopies: a comparative investigation. Supply of water to forest canopies is a major control of hydrological, atmospheric and biotic processes that impinge on groundwater stability, catchment yield, the fate of pollutants and plant productivity. Fundamental aspects of water transport and distribution within plant tissues remain obscured by conflicting experimental data and conflicting theoretical models that des ....Ecophysiological limitations that affect water and carbon balance within large tree canopies: a comparative investigation. Supply of water to forest canopies is a major control of hydrological, atmospheric and biotic processes that impinge on groundwater stability, catchment yield, the fate of pollutants and plant productivity. Fundamental aspects of water transport and distribution within plant tissues remain obscured by conflicting experimental data and conflicting theoretical models that describe physiological functioning.
Potential hydraulic constraints to the exchange of water and carbon between leaf and atmosphere require investigation before accurate models and informed decisions can be made with respect to the role of forests in biosphere-atmosphere processes. I will use large trees to investigate physiological and morphological determinants of hydraulic function and consider relationships between tree size, water requirements and water supply.
This project will foster comparative analyses of hydraulic functioning in large angiosperm and conifer species to elucidate universal principles that relate form to function and explain relationships between trees and their environment.
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Oxygen-18 in water, carbon dioxide, and organic matter: a tool for linking plant biological processes, hydrology and climate change. The globe is warming but pan evaporation is decreasing, because the world is dimming. We do not understand why. Stable, naturally occurring oxygen isotopes in plants (for example, tree rings) and in the carbon dioxide of the atmosphere vary and record climatic changes and physiological responses. Bringing these disparate areas of research together will help us to i ....Oxygen-18 in water, carbon dioxide, and organic matter: a tool for linking plant biological processes, hydrology and climate change. The globe is warming but pan evaporation is decreasing, because the world is dimming. We do not understand why. Stable, naturally occurring oxygen isotopes in plants (for example, tree rings) and in the carbon dioxide of the atmosphere vary and record climatic changes and physiological responses. Bringing these disparate areas of research together will help us to interpret the changes and responses. Such information is needed for planning future water requirements in Australia (agriculture, natural ecosystems, dams) and around the world. The isotopic composition of tree rings and of the atmospheric carbon dioxide is affected by that in water of leaves, and the processes linking them will be studied in detail. Read moreRead less