SOIL MANAGEMENT RESEARCH FOR WATER CONSERVATION AND QUALITY

Authors: Unger, Paul; Papendick, Robert; Steiner, Jean; Sharpley, Andrew; Edwards, William

Submitted to: Soil and Water Conservation Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/16/1996
Publication Date: N/A
Citation: N/A

Interpretive Summary: Additional water is highly important for nonirrigated crop production in subhumid, semiarid, and arid regions. This has been known for many years. However, research to improve soil water conservation (water storage in soil) began only in about the 1930s and 1940s for nonirrigated crops. Water conservation is important also for crops in more humid regions and with irrigation, but water conservation research under such conditions began somewhat later. Research to improve and protect water quality began even later. Many soil management and related practices affect water conservation and quality. These include tillage methods, cropping systems, crops grown, crop residue management, mulch, soil amendments, and various support practices for conserving water. The main goals for these practices are to increase infiltration (reduce runoff), decrease evaporation, and control weeds. To improve or protect water quality, goals are to reduce nutrient and pesticide movement to groundwater or to surface waters. Many practices that affect water conservation also affect water quality, but major infiltration should be avoided so that water does not move nutrients and pesticides to the groundwater. The timing and amount of nutrient or pesticide application and the use of cover crops also affect water quality. Effective practices for conserving water and protecting or improving water quality are available, but further research is needed to improve upon these practices. Also, programs are needed to make producers aware of the practices that are available for conserving water and protecting water resources. Future research and education programs should stress that these programs have long-term economic and environmental benefits to the entire society, not only to the producers on whose land the practices are used.

Technical Abstract: The importance of additional water for nonirrigated crop production in subhumid, semiarid, and arid regions has long been recognized. However, major research emphasis on soil water conservation (water storage in soil) began only in about the 1930s and 1940s for nonirrigated crops; it began somewhat later for crops in more humid regions and with irrigation. Major emphasis on water quality research began even later. Numerous soil management and related practices affect water conservation and quality. Included for water conservation are tillage methods, cropping systems, crops grown, crop residue management practices, mulch, soil amendments, and various support practices. Primary goals are to increase infiltration (reduce runoff), decrease evaporation, and control weeds. To improve or protect water quality, goals are to reduce nutrient and pesticide leaching to groundwater and transport in runoff to surface waters. Many practices affecting water conservation also affect water quality. However, excessiv infiltration should be avoided to reduce the leaching potential. Factors such as the timing and amount of nutrient or pesticide application and the use of cover crops also affect water quality. Soil management research has led to development of effective practices for conserving water and protecting or improving water quality. Further research is needed to improve upon these practices. Also, education programs are needed to gain wider acceptance of these practices for sustained crop productivity and protection of water resources. Future research and education programs should emphasize the long-term economic and environmental benefits of these programs to society as a whole, not only to producers on whose land the practices are applied.