论文部分内容阅读
为了揭示宁强县土壤侵蚀的空间分布特征,利用GIS技术,通过对宁强县土壤侵蚀强度分布图和DEM图的叠加,得到土壤侵蚀强度在坡度、坡向、高程、起伏度等地貌因子的分布特征。结果显示,宁强县水土流失程度为63.79%,土壤侵蚀强度以中度为主。不同坡度、高程、起伏度下的水土流失面积比例、土壤侵蚀综合指数和土壤侵蚀强度分别随着坡度增加、高程升高、起伏度上升呈先增大后减小的单峰分布趋势。平地的水土流失面积比例接近0,不同坡向的水土流失面积比例、土壤侵蚀综合指数和土壤侵蚀强度分布差异不显著。不同土壤侵蚀强度的最大值和分布范围均随着坡度的增加而增大,但却随着高程的升高而减小。各土壤侵蚀强度的起伏度分布均很相似。此结论可为区域水土保持规划和水土流失治理提供决策依据和理论支持。
In order to reveal the spatial distribution characteristics of soil erosion in Ningqiang County, by using GIS technology, through the superposition of soil erosion intensity distribution diagram and DEM diagram in Ningqiang County, the soil erosion intensity was obtained in the aspects of slope, aspect, elevation and undulation Distribution characteristics. The results showed that the degree of soil and water loss in Ningqiang County was 63.79%, and the intensity of soil erosion was mainly moderate. The proportions of soil and water loss, soil erosion index and soil erosion intensity under different slope, elevation and undulating degrees increased with the increase of slope, elevation and fluctuation of undulation, and then increased firstly and then decreased. The proportions of water and soil loss in the plain are close to zero. There is no significant difference in the proportion of soil and water loss area, the integrated index of soil erosion and the intensity of soil erosion in different slopes. The maximum and distribution range of soil erosion intensity increased with the increase of slope, but decreased with elevation. The distribution of undulation of soil erosion intensity is very similar. This conclusion can provide decision basis and theoretical support for regional soil and water conservation planning and soil erosion control.