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
Top-down rehydration: role of multiple water sources in mangrove function. This project aims to combine cutting-edge analytical and imaging techniques to assess contributions of atmospheric water sources to shoot-water balances, identify leaf traits associated with top-down rehydration, and determine the relative importance of different sources of water used by mangroves in maintenance of photosynthetic carbon assimilation along natural gradients in salinity and aridity. The capacity of shoots ....Top-down rehydration: role of multiple water sources in mangrove function. This project aims to combine cutting-edge analytical and imaging techniques to assess contributions of atmospheric water sources to shoot-water balances, identify leaf traits associated with top-down rehydration, and determine the relative importance of different sources of water used by mangroves in maintenance of photosynthetic carbon assimilation along natural gradients in salinity and aridity. The capacity of shoots to absorb atmospheric water could profoundly affect the diversity, survival and productivity of mangroves where high soil salinity limits water uptake by roots, particularly during hot, dry conditions.Read moreRead less
Role of top-down-rehydration in drought tolerance of mangroves. This project aims to understand the role of absorption and storage of atmospheric water (vapour, mist, rain, dew) by shoots in survival of mangroves where high soil salinity limits root water uptake, particularly during hot, dry conditions. This research will advance understanding of drought and salinity tolerance. The project outcomes will include identification of environmental conditions that limit drought survival and functional ....Role of top-down-rehydration in drought tolerance of mangroves. This project aims to understand the role of absorption and storage of atmospheric water (vapour, mist, rain, dew) by shoots in survival of mangroves where high soil salinity limits root water uptake, particularly during hot, dry conditions. This research will advance understanding of drought and salinity tolerance. The project outcomes will include identification of environmental conditions that limit drought survival and functional plant traits that enhance drought survival. These outcomes are fundamental to interpreting mechanisms underlying mangrove dieback under drought and will benefit the development of process-based models for better prediction of mangrove responses to climate change.Read moreRead less
Interactive effects of salinity and nutrients: linking physiological processes with patterns in mangrove forest productivity. The proposed research will provide insight into physiological mechanisms that underpin mangrove productivity along salinity and aridity gradients, and determine how these factors affect plant responses to nutrient enrichment. Plant traits that increase salt and drought tolerance will be identified, thereby assisting development of plant varieties suited to Australian cond ....Interactive effects of salinity and nutrients: linking physiological processes with patterns in mangrove forest productivity. The proposed research will provide insight into physiological mechanisms that underpin mangrove productivity along salinity and aridity gradients, and determine how these factors affect plant responses to nutrient enrichment. Plant traits that increase salt and drought tolerance will be identified, thereby assisting development of plant varieties suited to Australian conditions. The results will also contribute to development of process-based models to better manage mangrove resources with climate change and increasing nutrient influx from urban or agricultural activities. Such models are essential for managing mangrove productivity for sustainable fisheries, and protecting the ecological well being of the coastal zone.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.
Salinity tolerance along an aridity gradient: linking physiological processes with morphological constraints on leaf function in mangroves. The proposed research will provide insight into the physiological and morphological features that control the productivity of mangrove forests across broad gradients in salinity and aridity. Central to this is this identification of plant traits that increase salt and drought tolerance, which will assist in the development of plant varieties suited to Austra ....Salinity tolerance along an aridity gradient: linking physiological processes with morphological constraints on leaf function in mangroves. The proposed research will provide insight into the physiological and morphological features that control the productivity of mangrove forests across broad gradients in salinity and aridity. Central to this is this identification of plant traits that increase salt and drought tolerance, which will assist in the development of plant varieties suited to Australian conditions. The results will also contribute to development of process-based models to better predict the response of mangrove vegetation to changing climate. A deep understanding of the processes that influence the growth and survival of mangroves is of fundamental importance to sustainable fisheries and protection of wildlife reliant on coastal ecosystems. 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