Comparison of Soil Quality Indicators Among Different Farming Systems—Final Report
Soil quality indicators were compared in different farming systems at eight “pods” of neighboring farms around Iowa. Samples were collected for three years and analyzed for organic matter, total carbon and nitrogen content, bulk density, stable aggregate content and pH. Organic matter was higher in organic crops than conventional crops and higher in continuously-grazed pastures than in rotationally-grazed pastures. The nitrogen content was higher in rotationally-grazed pastures than in continuously-grazed pastures, and the nitrogen in the top six inches was higher in the organic crops than in the conventional crops. Stable aggregate content was higher in organic than conventional and higher in pastures than in annual crops but was not significantly different between the pasture management treatments.