Soil erosion and some means for its control

The control of soil erosion on the many farms where it is still a problem would not be difficult if it required only an understanding of the critical physical relationships between climate, topography, plant cover, water and soil as well as an ability to prescribe the proper engineering and agronomic measures for each situation. Soil losses, when greatly in excess of those produced by natural geological processes, result from the use of particular farming practices and cropping systems. While an understanding of the physical conditions which produce this erosion is essential, so is an understanding of the reasons that farmers choose the methods of farming which expose their soil to the hazard of heavy erosion losses.https://lib.dr.iastate.edu/specialreports/1027/thumbnail.jp

Soil conservation in perspective

xiii, 344 p. ; 24 cm

Soil erosion control in process in western Iowa

A previous study of the problems of controlling soil erosion losses on a sample of 144 farms in western Iowa indicated that several factors, largely economic in nature, were usually responsible for the failure of farm operators to use the practices necessary to reduce soil losses. Built upon the findings of this earlier research, the purpose of this second study was to examine further each farm situation and to determine whether changes in these obstacle factors were responsible for corresponding changes in the rate of soil loss. A second objective, to be treated in another bulletin, is to develop measures to overcome some of the obstacles in order to encourage a more effective and wider use of erosion-control practices. Progress among farmers in reducing soil erosion losses in western Iowa has been slow. This analysis of practices in the 144 sample farms showed an average decline of only 1.5 tons per acre in the annual rate of soil loss from 1949 through 1952. This average decline is misleading, however, because 69 farms increased erosion losses about 7 tons per acre per year, while 70 farms decreased erosion losses about 9 tons per acre per year. Individual farms revealed wide variations. The modal group's loss was 5 tons greater in the resurvey. The average rate of loss on all farms was still nearly 20 tons per acre annually. As a group, the operators had not succeeded in reaching their own goals of erosion control (16 tons per acre annually) which they had suggested 4 years earlier. If those goals had been reached, the average annual soil loss would have been reduced by 4 tons per acre, which is still about four times the conservation technicians' goal of 5 tons per acre of permissible soil-losses.</p