Surface water management for crop production on highly erodible land.
1990
Naderman G.C. | Hansard J.R. | Denton H.P.
Management of surface water has four broad objectives: (1) Appropriate removal of excess water during wet periods, (2) Water conservation for crop use, (3) On-site erosion control to protect long-term soil productivity and reduce short term damages, and (4) Off-site damage prevention from sedimentation and water pollution. The various techniques of water management vary in effectiveness for the four objectives given. However, for production of crops on erodible land the importance of water conservation to enhance yield and potential profits must be emphasized. The benefits of water management for on-site erosion control are well established. Economic studies, however, conclude that structural approaches to control on-site erosion are seldom profitable in terms of protecting soil productivity. The use of a tillage and cropping system designed for erosion protection is economically more attractive than structures, especially if the cropping system does not greatly reduce the total value of farm products sold. In contrast to the on site losses annual costs of off-site damages from cropland erosion and runoff are probably 10 to 55 times as great. Grain crop production on highly erodible land continues to be difficult and risky. Whether farmers can achieve this profitably, and with conservation compliance as defined by the 1985 Food Security Act, will greatly depend upon the alternative types of land available and the extent of conservation treatment required.
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