Tuesday, November 6, 2007
211-5

Assessment of Site Specific Conservation Systems Performance Utilizing Soil Physical and Biological Indices.

Mahdi Al-Kaisi1, Jamie Benning2, and Jose Guzman2. (1) Agronomy, Iowa State University, Ames, IA 50011, (2) Iowa State Univeristy, Ames, IA 50011

Soil and climate conditions play significant role in influencing conservation tillage systems performance. The main objective of this study is to evaluate a suite of conservation practices performance across Iowa. To achieve such objective the state was divided into five major regions based on soil formation and climate conditions.  In each region 5-10 sites were selected that include similar conservation systems treatments. Parameters such is yield, soil C, soil bulk density, residue cover, aggregate stability, microbial biomass, soil nitrate, and fall stalk nitrate concentrations were evaluated for each treatment. The preliminary results showed that differences in tillage treatment performance is highly site specific and affected by past management practices, climate, soil conditions, and current management.  Differences in soil quality parameters  that were associated with different conservation system were also highly site specific and influenced by soil formation and previous management practices.