Long-term effects of cropping systems and fertilizers on soil physical properties

Enhancing soil quality in intensive agricultural systems is important to su staining productivity and improving environmental quality. Crapping systems play an important role in determining soil physical characteristics and in nutrient cycling mechanisms. Field experiments were conducted at the Agron omy Farm of The Ohio State University, Columbus, Ohio on a well-drained Mia mian silty-clay loam soil to assess cropping systems effects on soil physic al properties. There were a total of 11 cropping system treatments involvin g 6 cover crops, 4 crop rotations and a fallow plot. All cropping system tr eatments were managed at two fertilizer levels. Dry soil aggregate stabilit y, mean weight diameter, and moisture retention were determined for the 0-1 0 cm layer. Aggregate stability was high (93-96%), and not significantly af fected by cropping systems and fertilizer levels. The mean weight diameter of aggregates varied from 5.9 to 6.1 mm. The cropping systems had no signif icant effect on mean weight diameter but the fertilizer level had a signifi cant effect on it. The effect of cropping system treatments on soil moistur e retention characteristics was significant only at near field capacity (-0 .1 MPa suction).