Grant: Discovery Launch Supplement

As centres of food consumption and waste production, cities are hotspots of resource flows on the landscape. Although decision-makers are trying to better manage urban nutrient flows, including through the implementation of ecological infrastructure programs, there is still a lack of empirical knowledge as to how such programs affect the fate of nutrients and the ecosystem services that depend on nutrient flows. It is urgently necessary to decrease losses of phosphorus and nitrogen to the environment and increase circularity. At the same time, strategies that are implemented must be both efficient under current conditions and support the resilience of food, water, and waste systems in the face of a changing climate. Increasing temporal variability in weather associated with climate change, and large spatial heterogeneity in the urban fabric make it especially difficult to gain generalizable knowledge and make recommendations for sustainable nutrient management in cities. Over the next 5 years, my students and I will tackle these challenges by investigating how urban nutrient flows are affected by climate change and how such nutrient flows can be better managed to contribute to meeting climate and other connected sustainability priorities. We will use urban and peri-urban agriculture as a form of ecological infrastructure, which are also hotspots of nutrient flows in and around cities, as a main study system. The team will quantify nutrient flows and drivers of their magnitude and direction and assess potential synergies and trade-offs among sustainability priorities. We will do this at three spatial levels: the regional watershed, the municipality, and at the local garden/farm level, with London, Ontario as a case site. We will also measure how changing seasonal temperature and precipitation patterns affect losses of nutrients from urban and peri-urban agricultural plots. Finally, we will develop models to explore future scenarios and the benefits and drawbacks of scaling up urban and peri-urban agriculture in the study system. Urban areas have a significant impact on global resource flows and urban landscapes are still expanding. My research strives to better understand how nutrients within these human-dominated landscapes, and beyond, cycle, and how humans can improve nitrogen and phosphorus management. This research program combines empirical and modeling approaches to integrate cross-scale dynamics in novel ways to advance our knowledge of urban nutrient flows. By building my research program in and around where our university is located, we will also be able to connect our work to my long-term objective of co-creating knowledge with local actors for evidence-based decision-making in an increasingly uncertain world.