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以金沙江干热河谷典型区段不同处理坡面和林地、农地集水区为研究对象,采用坡面径流小区和集水区卡口站三角形薄壁堰实测法,在坡面径流小区和集水区土地利用现状调查基础上,通过降雨、径流及泥沙观测,分析金沙江干热河谷典型区段水土流失特征。结果表明:(1)不同处理坡面径流小区产流量、产沙量大小依次为坡耕地>自然坡面>水平阶整地>反坡台整地,表明反坡台和水平阶造林整地以及植被良好的自然坡面对地表径流的拦蓄和对泥沙的削减都起到较好效果;(2)大暴雨对集水区尺度产流产沙贡献值大,产流降雨量在4.8～27.6mm区间,农地集水区径流深小于林地集水区,大于27.6mm时,农地集水区径流深反超林地集水区,而产沙量不受降雨量影响,为林地集水区低于农地集水区;(3)径流小区尺度与集水区尺度雨季水土流失起止时间一致,集水区径流系数小于径流小区,集水区产沙量大于径流小区。
In this paper, different treatments of slope and woodland and catchment area of agricultural land in the typical dry-hot valley of Jinsha River were taken as the research object. Using the triangular thin-walled weir of bayou runoff plot and catchment station in the catchment area, Based on the survey of land use status in water area, the characteristics of soil and water loss in typical sections of Jinsha River dry-hot valley were analyzed by rainfall, runoff and sediment observation. The results show that: (1) The runoff yield and sediment yield of the slope runoff plots with different treatments are in the order of sloping cropland> natural slope> horizontal order land preparation> anti-sloping land preparation, indicating that afforestation and afforestation of reverse sloping platform and horizontal order and vegetation are good (2) The heavy rain contributes a lot to runoff yield at catchment scale, and the rainfall runoff is in the range of 4.8 ~ 27.6mm. The farmland The runoff depth of catchment area is less than that of forest catchment area. When it is more than 27.6mm, the runoff of farmland catchment area overtakes the catchment area of forest land, while the sediment yield is not affected by rainfall, which is lower than that of farmland catchment area ; (3) The runoff plot size is consistent with the beginning and ending time of soil and water loss in catchment scale in rainy seasons, and the catchment runoff coefficient is smaller than that in runoff plot, and the sediment yield in catchment area is larger than runoff plot.