Habitat change, invasive species, overexploitation, climate change, and nutrient pollution are all contributing to a global biodiversity crisis, with global species loss far exceeding background extinction rates. At the local scale, these global change drivers alter the composition of ecological communities and influence how ecosystems function which, in turn, impacts the capacity for ecosystems to provide the services humans depend on. The non-random nature of species loss suggests that predictable patterns of biodiversity change in response to global change drivers exist. There is still much uncertainty in what these patterns are, how they compare across different global change drivers, and how generalizable local biodiversity change is across taxa, biomes, and geographic regions. Gaining a better understanding of how local ecological assemblages change in response to global change drivers will be essential in informing future ecosystem management and conservation priorities.

My PhD research uses a combination of meta-analyses and laboratory experiments to achieve four key objectives: 1) Quantify the magnitude and predictability of local-scale biodiversity change in response to five global change drivers and compare the effects across taxa and ecosystems, 2) Identify the geographic biases that exist in the local-scale biodiversity change literature that hinder ecologist’s ability to infer biodiversity change patterns worldwide and use these data gaps to develop recommendations for where further studies need to be conducted across the Earth’s biomes, 3) Explore the extent to which the single and combined impacts of global change drivers differ in their effects on key ecosystem processes, and 4) Use an aquatic model ecosystem to assess the single and interactive effects of overexploitation/phytoplankton decline and warming/acidification on biodiversity change over time.

PhD Student

Grace Murphy
Principal Investigator
Dalhousie University
Email: grace.murphy@dal.ca