半干旱黄土丘陵区坡地紫花苜蓿种植模式与径流的关系

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

不同的紫花苜蓿(Medicago sativa)种植模式控制水土流失的效果存在差异,在甘肃省榆中县孙家岔小流域研究了坡地紫花苜蓿不同种植模式与径流的关系。结果表明,坡地种植的紫花苜蓿草地的径流深与降水强度之间存在线性关系,且随着坡度的增加,产生径流的速率增大;坡地上紫花苜蓿拦截降水的效果显著优于坡耕地和荒坡地(P<0.01);在坡耕地和荒坡地上种植紫花苜蓿,并按5年一遇最大6h降水量的防御标准配套建设水平阶,可全部拦蓄坡面径流。

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（P〈0.01）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.