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为了较准确地评估汶川地震后理县的土壤侵蚀状况,该研究结合GIS、RS、USLE(universal soil loss equation)定量地分析了汶川地震灾区理县的潜在土壤侵蚀和实际土壤侵蚀状况,并对地震前后土壤侵蚀量做了简要的对比分析,并且从坡度、坡向、土地利用类型、高程4个方面系统地研究了不同侵蚀强度区的面积和土壤侵蚀量的变化。研究结果表明:震后理县全年土壤侵蚀量达844.46万t/a,平均侵蚀量为1957.79t/(km2·a),属于轻度侵蚀,相比地震前轻度侵蚀、强度侵蚀、极强度侵蚀区域面积都有很大增长,有林地、坡度≥30°～50°、海拔≥2000～3000m、坡向为南坡、西坡的地带土壤侵蚀比较严重。该研究为理县震后土壤侵蚀的预防和治理工作提供了很好的依据。
In order to evaluate the soil erosion in Li County after the Wenchuan earthquake, this study quantitatively analyzed the potential soil erosion and the actual soil erosion in Li County of Wenchuan earthquake area by using GIS, RS and USLE (universal soil loss equation) Soil erosion before and after the earthquake made a brief comparative analysis, and from the slope, aspect, land use types, elevation four aspects of the different erosion intensity of the area and the change of soil erosion. The results show that: after the earthquake, the total amount of soil erosion in Li County was 8.4446 million t / a and the average amount of erosion was 1957.79t / (km2 · a), which belonged to mild erosion. Compared with the slight erosion and intensive erosion before the earthquake, The area of intensity erosion has a great growth, with forest land, slope ≥30 ° ~ 50 °, elevation ≥2000 ~ 3000m, slope to the southern slope, the western slope of the soil erosion is more serious. This study provides a good basis for the prevention and control of soil erosion after the Lixian earthquake.