Greenbelts: An Economic Analysis of Riparian Corridors in the Agricultural midwest,
Contribution to Book
Research in Contemporary and Applied Geography
Agricultural nonpoint water pollution is an environmental problem of major importance in the Corn Belt. Greenbelts — corridors of riparian wetland forest and meandering channels along streams and rivers — present a promising alternative to greatly lessen the impacts of farm runoff on streams, rivers and reservoirs. Appropriate government action, however, has not been forthcoming. The purpose of this dissertation is to evaluate the effectiveness and economic efficiency of greenbelts in the central C o m Belt. The underproduction of riparian wetland forests, and the improved river quality they can provide, is conceptualized as a manifestation of market failure. The economic value of these ecosystems is estimated using three links: 1) the effect of greenbelts on sediment concentrations in rivers; 2) the effect of sediments and greenbelts on "river quality"; and 3) the economic value of improved river quality. Estimates of the reduction in sediment concentration attributable to greenbelts, derived from multiple regression analysis from a sample of 19 river basins in Iowa and Illinois, are 41.68 (IS.45) mg/1 for each percentage of the area of the highest order floodplain that is forested, and 51.83 (6.07) mg/1 for each percentage of the length of the highest order stream that is meandering. Contingent valuation estimates of mean annual willingness to pay for improved river quality, from a stratefied sample of 200 lowans and Illinoisans, are $30.50, $37.10, and $41.51 for recreation and $37.61, $47.16, and $43.22 for intrinsic values for river quality improvements from poor-fair, fairgood and good-excellent, respectively. Combining these results provides estimates for the value of greenbelts per acre in an inner and outer corridor. For an inner corridor of one to two "stream widths" the range is $89 - $722/year with a "best estimate" of $290. For an outer corridor, consisting of the remainder of the 100-year floodplain, the range is $44 - $299, with a "best estimate" of $128. These figures provide useful guidelines for a program of conpensating farmers for conversion of their floodplain croplands to riparian forest, thus improving river quality and correcting this market failure.
Lant, C.L., 1987. Greenbelts: An Economic Analysis of Riparian Corridors in the Agricultural Midwest, Research in Contemporary and Applied Geography 11(1): 1-9.