What's it worth? Improving land use planning through the modeling and economic valuation of ecosystem services.

摘要

The American landscape is urbanizing without full assessments of urbanization's true environmental costs and is endangering the delivery of critical ecosystem services. This is unintentional, resulting from a lack of known economic values for ecosystem services and ecosystem service delivery models and means for incorporating the results of such models into market-driven land use planning. Developing communities could benefit from the consideration of ecosystem services in land use planning, but lack relevant means for such analyses. This renders ecosystem services invisible in their planning. The three studies described here address the need to incorporate ecosystem services into planning by identifying local values for ecosystem services and illustrating how they, along with predictive models of ecosystem service delivery, can be used to evaluate land use policies' environmental impacts. The first study estimated the marginal implicit prices for changes in two ecosystem services, access to recreational open space and scenic quality, in an urban county, providing solid evidence of these services' values and suggesting how they could be used to inform policy making. The second study expanded the list of services, adding services provided by trees, and focused on a larger, two-county area. This study identified significant positive values for tree cover in local neighborhoods surrounding individual homes, but not on home parcels themselves. This suggests that tree cover provides neighborhood externalities that could be remedied using policies or incentives. The third study, which focused on a single, urbanizing city, illustrates a process for evaluating land use plans based on their environmental and economic consequences. This study identified ecosystem services' values and the likely impacts of land use change on them and used this information to evaluate a local land use plan, thus generating both information and methods to inform the land use planning process locally. These studies' results serve to inform local development, enabling it to occur in a more sustainable manner, and provide an example for later studies to follow in considering the environmental impacts of land transformation in planning. This research has great potential to improve the visibility of ecosystem services in local land use planning and, thus, to improve the ecological functioning of future landscapes.