NSF Award
2406481
Urban agriculture has expanded in many cities in recent years and has potential to provide a variety of ecosystem services for urban residents. There is a pressing need to quantify these benefits in order to assess how urban agriculture may be part of cities’ strategies for climate adaptation. However, the wide variety of management practices, combined with the complexity of urban contexts and a changing climate, makes it challenging to quantify these benefits and potential tradeoffs. This research builds on an ongoing long-term study that has shown how different soil amendment inputs alter water infiltration and nutrient cycling. This work provides policy-relevant data for cities developing guidelines around urban agriculture and organics waste recycling that is shared through collaborations with extension and agency partners. This project supports undergraduate research training and new curricula at the undergraduate and high school level. <br/><br/>The research addresses three objectives. Objective 1 is a continuation of an ongoing long-term experiment in which rates of nutrient recycling (recovery by crops of compost-derived nutrients) and loss (export via leachate) are measured in replicated plots that receive different types and amounts of compost. New water input treatments with different irrigation and rainfall simulation scenarios are added to better understand the interaction between climate change and the fate of compost-derived organic matter and associated nutrients that builds up in the soils of urban farms and gardens. From the resulting measurements, budgets are constructed for carbon, nitrogen, phosphorus, and water, in order to quantify nutrient recycling and loss, carbon sequestration, and cooling due to evapotranspiration. Objective 2 extends this research to understand the fate of compost-derived nutrients in urban farms and community gardens across Minneapolis-Saint Paul, which have a variety of background soil conditions and management practices. The project includes detailed interviews on soil management practices to construct nutrient budgets for ten farms and measurements of nutrient concentrations in leachate and along vertical profiles to determine the fate of excess nutrients. Objective 3 focuses on comparing various ecosystem services from different urban agriculture land use scenarios using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) suite of models. Calculations of food production and nutrient recycling potential for all scenarios are calculated directly based on project data. The InVEST models for carbon sequestration, urban cooling, urban flood risk mitigation, urban stormwater retention, nutrient delivery, and pollinator habitat are produced for these scenarios.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
