Zoning does not improve the availability of ecosystem services in urban watersheds. A case study from Upstate South Carolina, USA

Abstract

When making governance decisions, such as land-use plans, policymakers must decide if and how to balance economic growth with environmental conservation. Often, and frequently not by choice, these decisions are made with limited or poor-quality data, which is often either too theoretical or too fine-scale, leading to poor land use planning within urban watersheds. As a case study of a governance technique, we analyzed the function of zoning on the relationship between development and ecosystem services across 65 watersheds in South Carolina, USA. Our research question was whether zoning regulations have helped preserve natural capital. Habitat, carbon storage, nutrient and sediment export were measured using Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), which maps distributions of services based on ecological production functions. Over a ten-year window, increased development resulted in the loss of services. Zoning reduced the impact of development on phosphorus export, but not on other services, revealing the need for more explicit consideration of services in creation of zoning ordinances. If residents of urban watersheds want to benefit from development, improved and more accessible data and rigorous evaluation are important first steps towards improved governance decisions about zoning and regional planning in both public and private sectors.