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
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.
To grow or to store: Do plants hedge their bets? This project aims to resolve a long-standing question about the function of perennial plants: how much of the carbon taken up by photosynthesis is used immediately for growth, and how much is kept in reserve as insurance against future stress? This question is important to our understanding of how plants respond to stresses such as severe drought, and yet lack of data and theoretical modelling currently hampers our ability to answer it. By applyin ....To grow or to store: Do plants hedge their bets? This project aims to resolve a long-standing question about the function of perennial plants: how much of the carbon taken up by photosynthesis is used immediately for growth, and how much is kept in reserve as insurance against future stress? This question is important to our understanding of how plants respond to stresses such as severe drought, and yet lack of data and theoretical modelling currently hampers our ability to answer it. By applying novel data analysis and modelling tools to recent experimental results, the project plans to test hypotheses for how plants allocate carbon between growth and storage in response to stress. Insights from the project may underpin better management of Australia’s vulnerable ecosystems.Read moreRead less
Linking phytoplankton to fisheries using zooplankton size spectra. This project aims to develop innovative numerical methods to understand the dynamics, carbon export, and trophic structure of zooplankton. The trophic links between phytoplankton, zooplankton and fisheries are unknown. The size- frequency distribution of zooplankton (size spectrum) is an innovative method for estimating their growth, predation and production as food for fish. Analysis of a global synthesis of zooplankton size dis ....Linking phytoplankton to fisheries using zooplankton size spectra. This project aims to develop innovative numerical methods to understand the dynamics, carbon export, and trophic structure of zooplankton. The trophic links between phytoplankton, zooplankton and fisheries are unknown. The size- frequency distribution of zooplankton (size spectrum) is an innovative method for estimating their growth, predation and production as food for fish. Analysis of a global synthesis of zooplankton size distributions from tropical to polar environments are expected to reveal these vital rates of pelagic ecosystems. The zooplankton rates will reveal, for the first time, the link between phytoplankton and fisheries, and will significantly improve ecosystem models and global assessments of environmental change.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.
Determinants of substrate preferences and environmental applications of the copper membrane monooxygenases. The project aims to improve sustainability of environmental problems related to methane emissions, nitrogen cycling and pollution. We are developing tools targeting microbial genes correlated to all these issues. Data from these tests provides the information needed for monitoring environmental health and development of sustainable solutions.
Tipping points and early warning signals in complex ecosystems. This project aims to create a theory of early warning that uses spatial data available on system state, connectivity and environmental stress, and to create tools to infer the risk of ecosystem collapse. Many ecosystems have irreversible tipping points. Since their locations are often unknown, metrics may provide an early warning of collapse but are difficult to apply because they need long time series which are usually lacking. Thi ....Tipping points and early warning signals in complex ecosystems. This project aims to create a theory of early warning that uses spatial data available on system state, connectivity and environmental stress, and to create tools to infer the risk of ecosystem collapse. Many ecosystems have irreversible tipping points. Since their locations are often unknown, metrics may provide an early warning of collapse but are difficult to apply because they need long time series which are usually lacking. This project will use the Great Barrier Reef as a testbed because it has both long time series (standard approach) and rich spatial data (new approach), and exhibits early warning signs. We will use these tools to gauge whether symptoms on the Great Barrier Reef predict local collapse and to develop intervention plans.Read moreRead less
Mapping and Modelling the Ocean's Unseen Biodiversity. From the reef to the rainforest, Australia is famous for its unique biodiversity. Less well known is that Australia's coastline is predicted to be a global hotspot for biodiversity in marine microbes, the unseen life forces that maintain ocean health and productivity. This project aims to overcome historical technological and logistical hurdles by using cutting-edge sampling, genetic and modelling tools to provide the first models of microbi ....Mapping and Modelling the Ocean's Unseen Biodiversity. From the reef to the rainforest, Australia is famous for its unique biodiversity. Less well known is that Australia's coastline is predicted to be a global hotspot for biodiversity in marine microbes, the unseen life forces that maintain ocean health and productivity. This project aims to overcome historical technological and logistical hurdles by using cutting-edge sampling, genetic and modelling tools to provide the first models of microbial diversity patterns and organismal range in Australian marine systems. This is expected to be a crucial step for understanding the evolutionary and ecological processes that shape contemporary biodiversity.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.
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