基于RUSLE模型的淮河流域土壤侵蚀定量评价

为探究淮河流域的土壤侵蚀状况及其空间分布特征，基于GIS技术和RUSLE模型，通过运用降雨、土壤类型、DEM、遥感影像和土地利用类型等数据确定模型中的参数因子，对2000年至2015年间淮河流域涉及的189个县（市、区）的土壤侵蚀强度及其空间分异特征进行了定量分析。结果表明:淮河流域土壤侵蚀区域主要分布在上游河南和湖北的丘陵地区；流域2000至2015年间土壤微度和轻度侵蚀占总土壤侵蚀量的84.51% ~ 96.10%，土壤侵蚀状况较轻；流域的土壤侵蚀量由2000年的8647.00 × 104 t a?1减少至2015年的5045.14 × 104 t a?1，2000年到2015年轻度等级以上的土壤侵蚀强度大部分都向低一级强度转移，流域土壤侵蚀状况得到明显改善；其中，2000年到2005年，流域的土壤侵蚀表现为极强度等级及以下，2005年到2015年流域土壤侵蚀强度等级减弱，均表现为中度等级及以下；强度以上的土壤侵蚀面积由2000年的300.94 km2下降为2015年的27.60 km2，土壤侵蚀强度逐年减弱。说明淮河流域长期的土壤侵蚀治理措施是卓有成效的，未来需进一步重点关注的区域是在林地和草地集中、坡度大、海拔高和坡向偏北的区域，需要确定重点区域的开发边界，严格控制过度开发。

Quantitative Evaluation of Soil Erosion in the Huaihe River Basin Based on RUSLE Model

In order to explore the soil erosion situation and its spatial distribution in the Huaihe River Basin based on GIS technology and RUSLE model, we selected rainfall, soil type, DEM, remote sensing image and land use type as the parameters of the RUSLE model, to quantitatively analyze soil erosion intensities and its spatial distribution characteristics of 189 counties (cities, districts) in the Huaihe River Basin from 2000 to 2015. The results showed that the soil erosion areas in the Huaihe River Basin were mainly distributed in the hilly areas of the upper reaches in Henan and Hubei provinces. The area of soil erosion at very light and light grades accounted for 84.51% to 96.10% of the total area of soil erosion, which indicated that the soil erosion was relatively light from 2000 and 2015. The amount of soil erosion was decreased from 8647.00 × 104 t a?1 in 2000 to 5045.14 × 104 t a?1 in 2015, and soil erosion intensity was shifted from above the light level to the lower level from 2000 to 2015. The soil erosion situation in the watershed was significantly improved. The soil erosion in the watershed was below the extremely strong grade from 2000 to 2005, was weakened and was at or below a moderate level from 2005 to 2015. The area of soil erosion above the strong grade was decreased from 300.94 km2 in 2000 to 27.60 km2 in 2015, which indicated that the intensity of soil erosion was weakened year by year. The long-term control measures of soil erosion in the Huaihe River Basin were very effective. We should further focus on soil erosion in the areas with concentrated forest land and grassland, large slopes, high elevations, and north-slope directions. It is necessary to determine the development boundaries of key areas and strictly control over development in the future.