In an era of unprecedented environmental change, making accurate predictions about the ecological consequences remains a major scientific challenge. Species are composed of individual populations, which may be subject to different selection pressures &/ or include different levels of genetic diversity & therefore may respond differently to global change. Recent studies have demonstrated that the variability within a species, referred to as intraspecific variation, could provide additional sources of ecological resilience that have been previously underestimated. In general, one or a few seagrass species dominate estuaries & determine ecosystem structure, function & therefore, resilience. Thus, accounting for intraspecific variation could help to improve our predictions about seagrass & estuarine resilience in the face of increasing disturbance.
The International Panel on Climate Change (IPPC, 2013) highlights Mediterranean climate regions as being some of the most vulnerable to climate change. Increasing temperatures, declining precipitation, more frequent & intense extreme weather events are predicted. The aim of this PhD project is to determine the implications of these changes for two dominant seagrass species in southwestern Australian estuaries. We will experimentally simulate an extreme rainfall event that occurred in the Swan-Canning Estuary in 2017 to understand how environmental conditions can affect seagrass response. We will use reciprocal transplant experiments to detect the presence of locally adapted seagrass populations & whether these populations may persist under global change. Genetic diversity can enable populations to adapt to change & therefore, its importance for estuarine seagrasses will also be examined. The information derived from this research will be used to inform the single largest investment made by the state government (Regional Estuaries Initiative) to safeguard the health of estuaries across the southwest..
Department of Water and Environmental Regulation (DWER).
2018-2021
Ms Chanelle Webster – PhD Candidate
Associate Professor Kathryn McMahon
Professor Paul Lavery