多沙粗沙区梯田对径流影响的初步分析

Preliminary Analysis of the Runoff Influence on the Terrace in Areas of Course Sands and Strong Erosion

在分析梯田入渗规律及其对径流影响机理的基础上,分析了坡改梯对径流的影响,确定了黄土高原多沙粗沙区北、中、西南部的单位面积梯田对径流的影响量。结果表明:梯田对径流影响的最大值出现在北部,特别是较高质量梯田(1、2级)在丰水年份,值最大;中部是影响值最小的地区,这一特点除与该区地形地貌有关外,还与该地区降水量和降水强度较大、产生洪水过程多等因素有关;西南部的影响值处于中部和北部之间,主要是该区特定的地形地貌和降水量偏大,且年内分配相对不甚集中和高强度暴雨相对偏少等因素综合作用的结果。

On the basic of analyzing infiltrating rules of the terrace and its influence principle to runoff, the author analyzed the influence on the terrace changing from the slope to runoff, and determined the influence on the unit area terrace to runoff from the north, the central section and the south-west at areas with sand and coarse sediment in the Loess Plateau. The result showed that： The north of the influence on the terrace to runoff was the maximum, the value of the high quality （1, 2 levels） terrace in wet year was the maximum particularly. These characteristics were determined by land form,precipitation and the condition of the runoff generation and confluence; The minimum area was the central section, this characteristics were associated with the land form, but also with the high precipitation amount and precipitation intensity and the more flood process; The value influence in the south-west was between the central Section and the north, the mainly factors were the Specific land form and the high precipitation amount, and the annual distribution was not relative centralization and the high precipitation intensity relatively decreased.and so .on