青海湖北岸天然草地小尺度地表径流与降水关系

Correlation Analysis between Small-Scale Surface Runoff and Precipitation of the Grassland near the North Shore of Qinghai Lake

利用青海湖北岸海北牧业气象试验站2006-2008年3a观测的天然草地地表径流、土壤水分及大气降水资料,分析了该地区降水特性、土壤水分与地表径流的关系.结果表明:青海湖北岸年平均径流系数为0.16%,地表径流主要发生在夏秋季,径流系数夏季>秋季>春季,冬季不产生径流;地表径流造成的水土流失主要集中在盛夏的7-8月,年水土流失量主要由大降水造成.地表径流量与降水量呈线性正相关关系,径流量与30min最大雨强表现为指数函数关系,径流量与降水量和30min最大雨强的乘积也呈线性正相关关系.径流量的大小更多地受降水量和降水强度的共同影响,地表径流与降水前0～20cm的土壤水分呈明显正相关关系.

Based on the data of surface runoff,soil moisture and precipitation on grasslands from 2006 to 2008,the relationship among precipitation,soil moisture and runoff was studied,and the result shows that the runoff coefficient on the north shore of Qinghai lake is 0.16%,the surface runoff mainly takes place in summer,the runoff coefficient in summer is larger than that in fall,the runoff coefficient in fall is larger than that in spring,and there is no runoff event in winter. Soil and water loss caused by runof...