Who is Vulnerable to Ecosystem Service Change? Reconciling Locally Disaggregated Ecosystem Service Supply and Demand

Those living in marginal conditions can be vulnerable to changes in ecosystem services. Assessing vulnerability to ecosystem service change at disaggregated and community-relevant spatial scales is virtually absent in the literature. In this paper we develop a method to spatially assess communities' vulnerability to ecosystem service change by estimating trends in ecosystem service supply and demand interactions over time. We apply this method to analyze supply and demand dynamics around water security for 3873 settlements in the Miyun Reservoir watershed near Beijing, China. Community settlements were identified with high-resolution satellite imagery, allowing for a disaggregated assessment of supply and demand dynamics at a very fine spatial scale. Settlement-level demand trends are calculated with commonly available government statistics. Supply trends are estimated with land use data and common ecosystem service modeling software. Notably, our calculation of settlement-level ES supply is spatially aware, taking into account upstream communities' water needs. Our results reveal patterns of community vulnerability across the landscape and suggest ways to identify mechanisms that underlie communities' vulnerability risk. By analyzing trends over two periods, we are able to identify dusters that appear to adopt more sustainable management practices over time, and places where vulnerability to ES changes seems to persist.