Testing the importance of large-scale climate factors to plant community assembly following land-use change. This project will examine the native plant species and functional diversity of Australia's rain forest communities to create a predictive framework of how plant communities recover following deforestation. Such a framework is key to focusing conservation efforts in degraded and multi-use landscapes.
Seagrass denitrification: importance for global nitrogen budgets. The objective of this project is to use cutting-edge techniques to measure denitrification rates in communities dominated by different tropical and temperate seagrass species. Denitrification is a globally significant critical ecosystem process, but it is poorly understood in seagrass communities. This project is significant because of the potential importance of seagrass communities for nitrogen loss via denitrification in coasta ....Seagrass denitrification: importance for global nitrogen budgets. The objective of this project is to use cutting-edge techniques to measure denitrification rates in communities dominated by different tropical and temperate seagrass species. Denitrification is a globally significant critical ecosystem process, but it is poorly understood in seagrass communities. This project is significant because of the potential importance of seagrass communities for nitrogen loss via denitrification in coastal systems and the importance of coastal systems in the global nitrogen budget. The expected outcomes of this study may significantly advance our understanding of the functioning of coastal systems and global nitrogen budgets.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
Hydraulic control on water use, growth and survival in tropical rainforest. This project aims to measure drought-related limits to water transport in the woody xylem tissue of trees in Australian tropical rainforests, to understand how this influences tree water use, photosynthesis, health and mortality risk. Tropical rainforests are sensitive to climate variability, especially drought, but this sensitivity is poorly understood, despite large effects regionally and globally. This project will co ....Hydraulic control on water use, growth and survival in tropical rainforest. This project aims to measure drought-related limits to water transport in the woody xylem tissue of trees in Australian tropical rainforests, to understand how this influences tree water use, photosynthesis, health and mortality risk. Tropical rainforests are sensitive to climate variability, especially drought, but this sensitivity is poorly understood, despite large effects regionally and globally. This project will compare forests that contrast strongly in seasonal drought stress, and use the information to develop a model designed for species-diverse forest, with subsequent potential global application. The understanding gained will enable widely applicable advances designed to feed through rapidly to regional- and global-scale models that inform land use, economic and social policy-making.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
Next-generation vegetation model based on functional traits. Global vegetation models try to answer big questions, such as the effects of climate change and carbon dioxide (CO2) on ecosystems and vice versa. But as present models are outdated and give inconsistent results, the project is planning a new, more robust model that will fully exploit recent advances in plant functional ecology and earth system science.
Global change and food web structure: synergistic effects of multiple drivers of global change on species interaction networks. This project addresses the two great challenges facing scientists trying to predict the effects of global change on Australia's ecosystems: i) What factors most exacerbate the total impact of global change? ii) How do the complex responses of so many interacting species actually translate into altered structural properties of the web of life?
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.
Predicting the delivery of ecosystem services in agricultural landscapes. The ecological sustainability of Australian agriculture relies on services (for example, pollination) provided by ecosystems. Service provision is threatened by environmental change, but there is no established approach for predicting the impact of change on services. This project will undertake the most comprehensive experimental examination of ecosystem-service delivery ever conducted in Australia, testing the predictive ....Predicting the delivery of ecosystem services in agricultural landscapes. The ecological sustainability of Australian agriculture relies on services (for example, pollination) provided by ecosystems. Service provision is threatened by environmental change, but there is no established approach for predicting the impact of change on services. This project will undertake the most comprehensive experimental examination of ecosystem-service delivery ever conducted in Australia, testing the predictive capacity of an approach that links environmental change with variation in service provision through species’ traits. The major outcomes include greater capacity for agriculturalists to maximise ecosystem benefits and increase economic returns, and improved biodiversity conservation through recognition of its contribution to agriculture. Read moreRead less
Is the extreme phosphate sensitivity found among Australian plants a consequence of their adaptation to a severely phosphate-limited environment? The phosphorus (P)-impoverished soils of south-western Australia have allowed the evolution of many plants that are amazingly efficient at retrieving P from dying tissues. This project will contribute to the understanding of the mechanism determining P efficiency and will contribute significantly to the development of crops that are less reliant on non ....Is the extreme phosphate sensitivity found among Australian plants a consequence of their adaptation to a severely phosphate-limited environment? The phosphorus (P)-impoverished soils of south-western Australia have allowed the evolution of many plants that are amazingly efficient at retrieving P from dying tissues. This project will contribute to the understanding of the mechanism determining P efficiency and will contribute significantly to the development of crops that are less reliant on non-renewable P fertilisers.Read moreRead less