Nicola Day

Ecosystem resilience measures the stability and recovery of ecosystem functions when environments change. In the context of terrestrial ecosystems, both above and below ground factors – including diversity in species, traits, nutrient cycling, and species interactions – contribute to create resilient ecosystems. However, understanding the mechanisms and predicting the ecosystem resilience through the current period of global climate change is one of the greatest challenges in ecosystem management at present. We lack long-term data integrating above and below-ground ecological responses to climate change. 

Many regions in the world are projected to experience an increased incidence of fires due to climate change. New Zealand is no exception, and fires are expected to increase in the eastern South Island in particular. Dr Nicola Day has been awarded a Rutherford Foundation Postdoctoral Fellowship to examine the resilience of ecosystems under changing fire conditions focusing on tussock grasslands across Canterbury and Otago. She is currently working at Wilfrid Laurier University in Canada and will return to New Zealand to undertake this position at the Auckland University of Technology.

New Zealand’s tussock grasslands are an ideal case study for Dr Day’s proposed research because these ecosystems have experienced multiple aspects of global change, including repeated burning and introduction of non-native mammalian grazers since European colonisation. Dr Day’s research will build on a large-scale, long-term (25 years) plant community and soil datasets from 103 short and tall tussock grasslands across New Zealand’s South Island. Dr Day will enrich this data with new analysis of soil microbes and carbon circulation using targeted experiments to simulate the effects of fire.

The complete data set will be integrated into a predictive modelling framework of the impacts of fire on plant community structure, and wider ecosystem functioning. This research will enable us to identify and manage vulnerable parts of New Zealand’s grassland ecosystems and generate globally relevant  information on disturbance-resilience theory in a changing world.