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水土流失是鄱阳湖流域严重的生态环境问题。以USLE模型为基础,结合鄱阳湖流域自然环境特征,确定评价指标及其分级标准。运用GIS技术,实现研究区土壤侵蚀敏感性综合评价,揭示其流域空间分异特征及规律,并对流域土壤侵蚀产生的原因进行分析,提出了调控措施。研究表明:流域土壤侵蚀敏感性主要以中度和高度敏感为主,不敏感、轻度和极度敏感所占比例较少。从空间分布上来看,极敏感地区集中分布在赣东南部的宁都县和会昌县,赣中吉安县和泰和县,赣西北的万载县,赣东北的德兴市和上饶市;高度敏感地区主要分布在赣江、抚河、信江、饶河及修水这5条河流域中、上游河流两岸和鄱阳湖滨湖地区,以及坡度<25°的坡耕地、疏幼林地;中度敏感性地区分布面积最广,在整个流域内各地貌和用地类型(除水域外)上均有分布;轻度敏感性地区主要分布在赣西南的井冈山市、万安县、赣县、大余县一带,呈月牙形分布;不敏感地区以鄱阳湖及五河沿线向四周呈辐射状分布,还包括赣西北的拓林水库、赣西江口水库和赣东洪门水库等区域。
Soil and water loss is a serious ecological and environmental problem in Poyang Lake Basin. Based on the USLE model, combined with the natural environment characteristics of Poyang Lake Basin, the evaluation index and its grading standards are determined. Using GIS technology to achieve a comprehensive assessment of the sensitivity of soil erosion in the study area, revealing the characteristics and regularities of spatial heterogeneity in the basin, analyzing the causes of soil erosion in the basin and putting forward the control measures. The results show that: the sensitivity of soil erosion to watershed is mainly medium and highly sensitive, insensitive, and light and extremely sensitive. In terms of spatial distribution, extremely sensitive areas are concentrated in Ningdu County and Huichang County in the southeastern Jiangxi Province, Ji’an County and Taihe County in Jiangxi Province, Wanzai County in the northwestern Jiangxi Province, Dexing City and Shangrao City in the northeast of Jiangxi Province, and highly sensitive areas It is mainly distributed in five river basins including Ganjiang River, Fuhe River, Xinjiang River, Raohe River and Xiushui River, the upper reaches of the rivers and Poyang Lake, the lakeside areas of Poyang Lake and slope cultivated land with slope of <25 °, sparse forests; moderate sensitivity The area is the most widely distributed, with the distribution of landform and land use types (except water area) throughout the basin. The areas of mild sensitivity are mainly located in Jinggangshan, Wan’an, Ganxian and Dayu counties in the southwestern Jiangxi Province , Distributed in a crescent-shaped pattern. The insensitive areas are distributed radially around Poyang Lake and along the Five Rivers, including the Tuolin Reservoir in the northwestern Jiangxi Province, the Jiangxikou Reservoir in the west Jiangxi and the Hongmen Reservoir in the eastern Jiangxi.