Influence of various cropping systems on composition of surface runoff

Field experiment was undertaken at Agronomy Farm, Gujarat Agricultural University, Anand Campus, Anand, during 1992-93 and 1993-94, to study the effect of various cropping systems on composition of surface runoff water and eroded sediments using runoff piers, with ten treatments consisting of sole crop of pearl millet (PM), pigeonpea (PP), bidi-tobacco (BT) and groundnut (GN) and their intercropping systems (PM+GN, PP+GN, BT+GN and PM+PP), including cultivated (CF) and absolute fallow (AF) treatments. The content of various nutrients (N, P, K) in runoff water and sediment fractions was the highest under sole groundnut crop. Groundnut as intercrop with bidi-tobacco and pigeonpea crops increased the content of various nutrients in runoff water arid in sediment fractions in comparison to that in respective sole crops. Among various cropping systems, sediment density under sole groundnut plot was significantly lower (2572 mg L-1) than in the rest of the cropping systems. A significant reduction in sediment density was observed when groundnut crop was taken as intercrop with bidi-tobacco and pigeonpea crops, than that under their respective sole crops.