Submitted to: Washington State University College of Agriculture and Home Economics
Publication Type: Other
Publication Acceptance Date: January 20, 2002
Publication Date: June 20, 2002
Citation: Kennedy, A.C. Soil quality of conservation tillage for wind erosion control. Annual Research Reports. Washington State University Agricultural Research Station, Pullman, WA. 2002. 2001. p. 130-132. Interpretive Summary: Soil quality parameters were assessed at several long-term dryland cropping systems research sites in eastern Washington. The objective was to characterize soil quality changes over time as affected by no-till versus traditional tillage-based management systems. Organic carbon increased over time with long-term no-till. Changes in the microbial community and other soil quality parameters such as pH, electrical conductivity and microbial enzyme activity were variable in their response. Soil quality changes during the transition to no-till take longer and are more variable in the low precipitation zone. Information from these long-term experiments will allow us to better assess the health or quality of soils in the dryland cropping region of the Inland Pacific Northwest to aid farmers in the transition to no-till cropping.
Technical Abstract: Soil quality parameters are being assessed at several sites to determine the health of a soil by defining management practices that are soil building rather than degrading. The objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in minimum tillage and no-till seeding systems as affected by tillage, crop species and management systems. The goal is to identify soil quality parameters that can be used in the development of best management practices for conserving soil quality and enhancing crop production. Overall we found that as the time into no-till increased, so too did measurable differences in organic carbon, the microbial community and bulk density. The change with soil quality parameters in the transition period to no-till appears to take longer and be more variable in lower rainfall zones. Cropping systems changes were difficult to consistently measure, possibly due to the short-term nature of the studies. Other results varied with site. From this research, information will be obtained to better assess the health or quality of soils specifically for the dryland-farming region. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.