The relationship between sloping fields alfalfa cropping pattern and runoffin Semi-arid Loess Hilly Area

Different alfalfa cropping patterns did not have the same effects on soil erosion control. The relationship between alfalfa cropping patterns and runoff was studied. The experimental results in Sun Jiacha Watershed, Yuzhong County, Gansu Province showed that there was a linear relationship between the runoff depth in slope cultivation alfalfa grass and rainfall intensity, and the generation rate of runoff increased with the increase of the slope. There were significantly difference(P0.01)for rainfall block effects in alfalfa slope cultivation, sloping land and wasteland. Alfalfa planted in the sloping land and wasteland which matched with five years a case of maximum 6 h rainfall design can impounded all the slope runoff.