An Ecosystem Service Approach to Assessing Agro-Ecosystems in Urban Landscapes

Abstract

Creating sustainable urban landscapes in light of growing population pressures requires interdisciplinary multi-functional solutions. Alternative agro-ecosystems described as food forests, permaculture gardens, and/or edible landscapes among others could offer potential ways to address the social, economic, and ecological goals of various stakeholders simultaneously. Current research is lacking a comprehensive tool that can assess the performance of alternative agro-ecosystems that have both functional and aesthetic values. The present research uses a novel rubric, the Permaculture and Agro-ecosystems Sustainability Scorecard (PASS) that combines agricultural sustainability and ecosystem services (ES) indicators in order to assess alternative agro-ecosystems. The rubric evaluates provisioning, regulating, supporting, economic and cultural ES and includes benefits such as pollinator presence, increased biodiversity, alternative pesticides and fertilizer use, carbon sequestration, food security, and human interactions. Based on the concepts and principles drawn from four popular frameworks and sub-disciplines, namely, SAFE, SITES, permaculture, and agroecology, we identify sixteen broad ES indicators and 59 sub-indices and measure them using data collected through site observation, survey, interviews, and documentary research. For easy comparison across different urban agriculture sites, the above sub-indices are further aggregated into five ES criteria using stakeholder-informed weights. The weights are developed through pair-wise comparison of criteria by sample survey respondents. The PASS framework is used to score twelve sites in South Florida that meet specific criteria in the small farm, residential, and public space categories. Sample respondents place the highest weight on cultural services. Contrary to the popular notion of promoting urban agriculture for food security, the results show that the majority of the sites score highest in the supporting services provided, followed by regulating and cultural services, and lowest in the economic services category. The supporting service for most of the sample sites score consistently very high, close to the highest possible level of 5.0. There is a wide variation in provisioning and economic values across the study sites. The paper offers several ideas for mainstreaming the ES indicators into urban planning and decision-making and some of the practical difficulties one might face along the way. We conclude that in order to realize the broader ES benefits of urban agriculture in particular and agro-ecosystems in general, a multi-pronged policy and planning approach is necessary.