How arid zone wetlands persist: linking ecological dynamics with hydrological regimes . This project will investigate how aquatic food webs assemble and persist in mound springs, relict streams and river pools in the Australian arid zone. Knowing how aquatic systems respond to wet and dry phases is the first step towards ‘climate proofing ’ these systems against future extreme events.
Toxic cyanobacterial blooms in a carbon dioxide (CO2)-rich world: assessing the impacts of global climate change. Cyanobacterial blooms in Australia cost the country over $150 million every year because of their impacts on water quality and animal and human health. The frequency, distribution and intensity of these blooms are all expected to increase worldwide as global climate change impacts increase over the next century. This project will provide much needed information of the severity of imp ....Toxic cyanobacterial blooms in a carbon dioxide (CO2)-rich world: assessing the impacts of global climate change. Cyanobacterial blooms in Australia cost the country over $150 million every year because of their impacts on water quality and animal and human health. The frequency, distribution and intensity of these blooms are all expected to increase worldwide as global climate change impacts increase over the next century. This project will provide much needed information of the severity of impacts on cyanobacteria commonly causing blooms in Australian aquatic ecosystems. This information will be important to authorities responsible for managing our precious water resources.Read moreRead less
New approaches to measuring the composition and nutrient status of single phytoplankton cells. Phytoplankton support 90% of aquatic food webs, and are responsible for nearly half of global primary productivity. Conversely, blooms of some phytoplankton, often associated with excess nutrients, can cause major environmental problems, including fish kills and risks to human health. However, current methods for determining the nutrient status of phytoplankton are time consuming and ignore the complex ....New approaches to measuring the composition and nutrient status of single phytoplankton cells. Phytoplankton support 90% of aquatic food webs, and are responsible for nearly half of global primary productivity. Conversely, blooms of some phytoplankton, often associated with excess nutrients, can cause major environmental problems, including fish kills and risks to human health. However, current methods for determining the nutrient status of phytoplankton are time consuming and ignore the complexity of responses of different species in mixed populations. This project will develop new, rapid, ways of examining the nutrient condition of individual algal cells, which will be of considerable use to the water industry as well as to our understanding of aquatic ecology.Read moreRead less
Dispersal and species coexistence across patchy landscapes. Millions of dollars are spent rehabilitating degraded river ecosystems in the absence of knowing whether and how species will be able to disperse to and re-populate repaired sections. This research will provide definitive information allowing restoration efforts to be targeted properly in streams surrounded by, and serving, agricultural areas.
Species coexistence in the real world. This project aims to discover how similar species co-exist without weaker competitors going extinct. Hypotheses offer explanations for stable coexistence in the presence of competition, but logistic barriers mean field tests are almost completely lacking. Recent research on competition and dispersal presents an opportunity to deliver tests using riverine species, leading to experiments at landscape scales. The research will quantify the role of environmenta ....Species coexistence in the real world. This project aims to discover how similar species co-exist without weaker competitors going extinct. Hypotheses offer explanations for stable coexistence in the presence of competition, but logistic barriers mean field tests are almost completely lacking. Recent research on competition and dispersal presents an opportunity to deliver tests using riverine species, leading to experiments at landscape scales. The research will quantify the role of environmental variability and dispersal in permitting stable coexistence of species, thus filling a major knowledge gap. The project expects to provide fresh avenues for research into the causes of species losses – particularly for the 70 per cent that are invertebrates.Read moreRead less
Resource patchiness, dispersal and species co-occurrence: an experimental and levels-of-evidence approach in some lowland streams. Millions of dollars are being spent on rehabilitating river ecosystems that have often been highly simplified by human activities. It is important that such rehabilitation be well-grounded in sound ecological knowledge. We will test how the availability of essential resources of food and living space affect the identity and density of species present. We expect to p ....Resource patchiness, dispersal and species co-occurrence: an experimental and levels-of-evidence approach in some lowland streams. Millions of dollars are being spent on rehabilitating river ecosystems that have often been highly simplified by human activities. It is important that such rehabilitation be well-grounded in sound ecological knowledge. We will test how the availability of essential resources of food and living space affect the identity and density of species present. We expect to provide practical advice allowing managers to enhance biodiversity in streams surrounded by, and serving, agricultural areas. Likewise, we will be able to advise on the consequences of excessive water extraction on the likely success of such rehabilitation in rivers with highly variable flows.Read moreRead less
Explaining species diversity in a fractal world. This project aims to improve our understanding of landscape-scale patterns of species diversity, particularly invertebrates. A central question in ecology asks how habitat patchiness interacts with dispersal abilities to determine species diversity. Field tests of hypotheses are lacking due to logistic difficulties in quantifying habitat patchiness and dispersal over landscape scales. A new model proposes that fractals (a clever way of measuring e ....Explaining species diversity in a fractal world. This project aims to improve our understanding of landscape-scale patterns of species diversity, particularly invertebrates. A central question in ecology asks how habitat patchiness interacts with dispersal abilities to determine species diversity. Field tests of hypotheses are lacking due to logistic difficulties in quantifying habitat patchiness and dispersal over landscape scales. A new model proposes that fractals (a clever way of measuring environmental complexity) can capture both habitat patchiness and species' responses. Advances in river ecology have solved the logistic problems and will allow tests to compare the three main hypotheses about species diversity. The project aims to improve information about which tools will provide the best guidance, benefitting the discipline of ecology and conservation managers.Read moreRead less
Ecological renovation of constructed wetlands: changing state from algae to macrophyte dominated systems. Mars Confectionary's constructed wastewater treatment wetlands no longer purify its waste waters. Over-burdening has tipped the balance from a plant dominated, clear water system to an algae dominated, turbid system. This project will aid restoration of the Mars wetlands by (1) improving our understanding of alage-macrophyte dynamics in shallow water basins; (2) producing a series of soft en ....Ecological renovation of constructed wetlands: changing state from algae to macrophyte dominated systems. Mars Confectionary's constructed wastewater treatment wetlands no longer purify its waste waters. Over-burdening has tipped the balance from a plant dominated, clear water system to an algae dominated, turbid system. This project will aid restoration of the Mars wetlands by (1) improving our understanding of alage-macrophyte dynamics in shallow water basins; (2) producing a series of soft engineering, ecologically based techniques for the management / rehabilitation of natural and constructed shallow water bodies which receive high nutrient loads; (3) improve decision support tools for the renovation and sustainable management of the Mars Confectionary, and similar food processing industry constructed wetlands.Read moreRead less
Nutrient Cycling in Lagoon of Islands,Tasmania: management to control eutrophication. Hydro Tasmania manages the Lagoon of Islands, a shallow freshwater lake on Tasmania's central plateau. The lagoon provides irrigation water and supports a significant recreational fishery. Over the last decade the lake has suffered increased nutrient enrichment, despite catchment management works to reduce external nutrient loads.
Preliminary nutrient budgets suggest that a significant proportion of the wat ....Nutrient Cycling in Lagoon of Islands,Tasmania: management to control eutrophication. Hydro Tasmania manages the Lagoon of Islands, a shallow freshwater lake on Tasmania's central plateau. The lagoon provides irrigation water and supports a significant recreational fishery. Over the last decade the lake has suffered increased nutrient enrichment, despite catchment management works to reduce external nutrient loads.
Preliminary nutrient budgets suggest that a significant proportion of the water column nutrient load comes from the sediments, phytoplankton or macrophytes. Internal nutrient loads and loading mechanisms will be characterised. Cost effective strategies for their management will be developed utilising hydrological manipulation - a largely unexplored technique.Read moreRead less
Diadromous stream fishes: a model system for investigating sources of variation in recruitment. Our aim is to examine the relationship between adult abundance and recruitment in local populations of a diadromous stream fish to identify the source(s) of variation in recruitment. We will accomplish this by measuring larval production and recruitment among streams that vary in adult abundance, strength of settlement cues, and potential for larval dispersal. We will also use environmental markers of ....Diadromous stream fishes: a model system for investigating sources of variation in recruitment. Our aim is to examine the relationship between adult abundance and recruitment in local populations of a diadromous stream fish to identify the source(s) of variation in recruitment. We will accomplish this by measuring larval production and recruitment among streams that vary in adult abundance, strength of settlement cues, and potential for larval dispersal. We will also use environmental markers of larval origin to quantify the degree of self-recruitment and dispersal within/among populations. The results will broaden our understanding of the influence of local (production, habitat) versus regional (dispersal) processes to local population dynamics, information needed for effective stream management.Read moreRead less