Ecosystem services in Rocky Mountain wetlands: a rapid assessment framework

Abstract

Healthy wetlands provide the public with important ecosystem services (ES) that improve human well-being. A robust wetland ecosystem can reduce flooding, supply drinking water, sequester carbon, minimize pollution, support irrigation, and provide an abundance of recreational opportunities. The primary goal of my research was to develop a rapid assessment tool for ES that will inform permitting decisions for section 404 of the Clean Water Act and allow users to quantitatively address the Environmental Protection Agency's goal of "no-net-loss of function or values" for wetland ecosystems. Current models address only wetland functions but provide a means of accounting for and replacing these functions through compensatory mitigation. They do not account for loss of ES or provide a way of replacing these benefits when losses are unavoidable. This project helped determine how ecological processes, biophysical characteristics, and structural attributes are related to wetland ES; broadening the current understanding of a wetland's capacity to perform specific services and offering a quantitative approach to accounting for the benefits that wetlands provide. Ten ES were identified by a previous study as the most important services according to wetland scientists and decision-makers in Montana and the surrounding eco-region. Sets of potential assessment metrics were identified for these services and a framework for an ES tool was developed for one of the highest-ranked services: flood attenuation. This was accomplished by combining biophysical indicators of function from an existing function assessment tool--Montana Wetland Assessment Methodology--with metrics that specifically relate to beneficiary engagement and ES capacity. Indicators were also identified for other important services that could be implemented into a future rapid ES assessment tool. This rapid assessment framework provides a means of quantifying services through simple geospatial analyses and open-source databases. Accounting for these services in this manner should improve the management of wetlands and ensure that beneficial services lost due to agriculture and development are being effectively replaced by compensatory mitigation efforts.