[目的]根据中国土壤流失方程(CSLE),在降雨、土壤、植被等因子一定的条件下,将梯田作为地形因子计算流域土壤侵蚀量,并与梯田作为工程措施的计算结果进行对比分析,为土壤侵蚀定量评价提供新的思路。[方法]以黄土高原地区的纸坊沟流域和燕沟流域作为试验区,利用5m分辨率的DEM,0.3m分辨率的WorldView3,30m分辨率的Landsat8影像、降雨数据、土壤数据、土地利用等数据。[结果](1)在纸坊沟流域和燕沟流域,坡式梯田作为地形因子的流域土壤侵蚀量大于梯田作为工程措施的流域土壤侵蚀量,同时坡式梯田作为地形因子的流域土壤侵蚀量大于水平梯田作为地形因子的流域土壤侵蚀量,而水平梯田作为地形因子的流域土壤侵蚀量与梯田作为工程措施的流域土壤侵蚀量的比较根据流域的不同结果不同。(2)梯田占流域面积比例不同时,随着梯田占比的升高,梯田作为工程措施的流域土壤侵蚀量要明显低于梯田作为地形因子的流域土壤侵蚀量。[结论]梯田作为地形因子和工程措施因子会对土壤侵蚀量计算产生一定影响,梯田占比较大时差异明显。
[Objective] With the using of CSLE model, we calculated the soil loss in two situations under certain conditions of rainfall, soil and vegetation: taking terraces as a terrain factor or as an engineering measure factor. It was expected to provide a new idea for quantitative evaluation of soil erosion. [Methods] This thesis choose Zhifanggou watershed and Yangou watershed of Loess Plateau as experimental sample plots and used DEMs of the study regions with a resolution of 5 meters, images of WorldView 3 with a resolution of 0.3 meters and Landsat 8 with a resolution of 30 meters, precipitation data, soil data and land use data, etc. [Results] (1) In Zhifanggou watershed and Yangou watersheds, as a terrain factor, the calculated average soil loss of watershed in slope terraces are both greater than the ones taking terraces as an engineering measure factor. However, the comparison results between the average soil loss of watershed in level terraces and taking terraces as an engineering measure factor varied in different watersheds. (2) As the increase of the proportion of terraces, the average soil loss of watershed taking terraces as an engineering measure is much lower than the one taking terraces as a terrain factor. [Conclusion] Taking terraces as terrain factor or engineering measure factor can change the calculation of soil loss, especially when the proportion of terraces is larger.