Ecological and statistical models were developed using freshwater algal assemblages to assess water quality and ecological health of a regulated river. These models were used to inform configuration of flows to maintain or improve environmental conditions of the waterway whilst meeting consumptive water supply commitments. The flow regime of the MacKenzie River, western Victoria, Australia, has been substantially modified since the construction of a water supply reservoir on its upper reach in 1887.
View Article and Find Full Text PDFMitigating climate change while safeguarding biodiversity and livelihoods is a major challenge. However, rampant afforestation threatens biodiversity and livelihoods, with questionable benefits to carbon storage. The narrative of landscape degradation is often applied without considering the history of the landscape.
View Article and Find Full Text PDFMangrove ecosystems can absorb significant amounts of carbon and help mitigate climate change. However, their existence continues to be endangered by natural and human forces. Therefore, mangrove restoration is regarded as a crucial component of the global climate change agenda.
View Article and Find Full Text PDFThe flow regime of the Wimmera River was substantially modified due to the construction of a water supply reservoir. Samples of diatoms and soft algae and measurements of water quality were analysed at ten sampling sites for 3 years (between February 2012 and November 2014) along the MacKenzie River, a tributary of the Wimmera River, in different seasons and under different flow regimes, to understand the spatial and temporal variation in the relationship between algal communities, water quality and stream condition. Baseline information on algal communities and water quality was collected during base flow conditions, while experiments on the effect of water releases on algal communities were based on flow regime variations (manipulated flow regimes), specifically on the algae community structure, water quality and ecosystem function.
View Article and Find Full Text PDFLarge rivers, including the Murray River system in southeast Australia, are disturbed by many activities. The arrival of European settlers to Australia by the mid-1800s transformed many floodplain wetlands of the lower Murray River system. River impoundment and flow regulation in the late 1800s and, from the 1930s, resulted in species invasion, and elevated nutrient concentrations causing widespread eutrophication.
View Article and Find Full Text PDFBiol Rev Camb Philos Soc
June 2019
In the 12 years since Dudgeon et al. (2006) reviewed major pressures on freshwater ecosystems, the biodiversity crisis in the world's lakes, reservoirs, rivers, streams and wetlands has deepened. While lakes, reservoirs and rivers cover only 2.
View Article and Find Full Text PDFMonitoring forms the basis for understanding ecological change. It relies on repeatability of methods to ensure detected changes accurately reflect the effect of environmental drivers. However, operator bias can influence the repeatability of field and laboratory work.
View Article and Find Full Text PDFThe ecological response of shallow oxbow lakes to variability in hydrology and catchment development in large river floodplain ecosystems (RFE) in Arkansas remains largely unknown. Investigating these responses will advance our understanding of ecological evolution of oxbow lakes in response to the major environmental drivers, which will establish baseline conditions required to develop effective management practices for RFE. In this pilot study, we examined the potential of using a dated surface sediment core from Adams Bayou, a floodplain lake located within the Cache-Lower White River Ramsar site in SE Arkansas.
View Article and Find Full Text PDFIntensification of the use of natural resources is a world-wide trend driven by the increasing demand for water, food, fibre, minerals and energy. These demands are the result of a rising world population, increasing wealth and greater global focus on economic growth. Land use intensification, together with climate change, is also driving intensification of the global hydrological cycle.
View Article and Find Full Text PDFThe concepts of ecosystem regime shifts, thresholds and alternative or multiple stable states are used extensively in the ecological and environmental management literature. When applied to aquatic ecosystems, these terms are used inconsistently reflecting differing levels of supporting evidence among ecosystem types. Although many aquatic ecosystems around the world have become degraded, the magnitude and causes of changes, relative to the range of historical variability, are poorly known.
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