Submitted to: Soil and Water Conservation Society
Publication Type: Abstract Only
Publication Acceptance Date: 7/20/2003
Publication Date: N/A
Technical Abstract: At several long-term dryland cropping systems research sites in eastern Washington and northern Idaho, soil quality parameters were assessed to further define management practices that are soil building rather than degrading. Our objective was to characterize soil quality changes between 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 are less perceptible and are more variable in the low (150¿ to 300¿ mm annual) precipitation zones compared to the higher (300¿ to 550¿ mm annual) precipitation zones. The addition of irrigation water to Lind soils appears to shorten the transition time. The continuous winter wheat burn plow treatment is showing signs of being degradative to soil quality. Differences due to various crops in rotation or residue treatments are not yet evident. With direct seeding, the lower disturbance has more of an impact on soil quality measurements than surface residue management. Data from these long-term experiments will allow us to better assess the productivity and quality of soils in the dryland cropping region of the Inland Pacific Northwest to aid farmers in the transition to no-till cropping.