基于土壤侵蚀控制度的黄土高原水土流失治理潜力研究

以整个黄土高原为研究对象,首先将水土保持措施容量定义为某一区域能容纳的最大适宜水土保持措施量。根据梯田、林地和草地的适宜布设区域,在地理信息系统（GIS）软件的支持下,确定了黄土高原的水土保持措施容量。使用修正通用土壤流失方程（RUSLE）,计算了最小可能土壤侵蚀模数和2010年现状土壤侵蚀模数,并将水土保持措施容量下的最小可能土壤侵蚀模数与现状土壤侵蚀模数之比定义为土壤侵蚀控制度。随后使用土壤侵蚀控制度,对黄土高原水土流失治理潜力进行了研究。结果显示：黄土高原2010年现状土壤侵蚀模数为3355 t·km^-2·a^-1,最小可能土壤侵蚀模数为1921 t·km^-2·a^-1,土壤侵蚀控制度为0.57,属于中等水平。相比于现状条件,在水土保持措施容量条件下,微度侵蚀区比例从50.48%提高至57.71%,林草覆盖率从56.74%增加至69.15%,梯田所占比例由4.36%增加到19.03%,人均粮食产量可从418 kg·a^-1提高至459 kg·a^-1。研究成果对于黄土高原生态文明建设具有一定的指导意义。

The capacity of soil loss control in the Loess Plateau based on soil erosion control degree

The capacity of soil and water conservation measures, defined as the maximum quantity of suitable soil and water conservation measures contained in a region, were determined for the Loess Plateau based on zones suitable for establishing terraced fields, forestland and grassland with the support of geographic information system (GIS) software. The minimum possible soil erosion modulus and actual soil erosion modulus in 2010 were calculated using the revised universal soil loss equation (RUSLE), and the rate of the minimum possible soil erosion modulus under the soil and water conservation measures to the actual soil erosion modulus was defined as the soil erosion control degree. The control potential of soil erosion and water loss in the Loess Plateau was studied using this concept. Results showed that the actual soil erosion modulus were 3355 t·km^-2·a^-1, the minimum possible soil erosion modulus was 1921 t·km^-2·a^-1, and the soil erosion control degree was 0.57 (medium level) on the Loess Plateau in 2010. In terms of zones, the control degree was relatively high in the valley plain zones, soil and rock mountainous zones, and windy sand zones, but relatively low in the soil and rock hilly forest zones, hilly gully zones and plateau gully zones. In terms of river basins, the soil erosion control degree was relatively high in the Dahei River, Huangfu River, Qingshui River, Kuye River and Pianguan River basins, but relatively low in the Qingjian River, Wuding River, Jialu River, and Yanhe River basins. The rate of erosion zones with a soil erosion modulus of less than 1000 t·km^-2·a^-1 increased from 50.48% to 57.71%, forest and grass coverage rose from 56.74% to 69.15%, ratio of terraced fields increased from 4.36% to 19.03%, and per capita grain yield rose from 418 kg·a^-1 to 459 kg·a^-1 under the soil and water conservation measures compared with actual conditions.