A Recent Trend in Ecological Economic Research: Quantifying the Benefits and Costs of Improving Ecosystem Services

Over the last two decades, the U.S. federal government spent about 2 billion dollars annually on the conservation of cropland. Such expenditures were supplemented with sizable state and local government funding. However, our understanding is incomplete as to the impacts of these expenditures on the use of conservation practices and their environmental effectiveness. Expanded knowledge on these issues is greatly needed to support societal decisions as to how much more, if any, we must do to improve environmental quality to a desired level. In this article, we provide some insights into these issues by examining two broad questions as applied to the state of Iowa: 1) What conservation practices are currently in place, what is their coverage, and what is the cost of these practices? 2) What have been the environmental impacts of the currently-installed conservation practices? To address the first question, we collected data from various surveys, and from federal and state conservation program sources. A database was established for some major conservation practices with regard to their costs and coverage. An estimate was also made for total statewide annual costs. The challenges and problems encountered in establishing accurate statewide cost estimates will be discussed. In order to answer the second question, the widely used Soil and Water Assessment Tool (SWAT) water quality model was employed to estimate the impacts of key conservation practices. We simulated the hypothetical removal of all existing conservation practices from the landscape and compared the impacts with current baseline conditions that included the conservation practices. The advantages and drawbacks of modeling will be identified to put our results in perspective.