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一、基本情况我县地处宁夏南部,属黄土高原水土流失综合治理区。全县土地面积471.5万亩(其中耕地282万亩),15°以上坡地有158.8万亩,占总面积33％。坡地水土流失比较严重,全县土壤平均年侵蚀模数为3952吨/平方公里,年侵蚀总量1242万吨,年平均流失表层肥土厚度为0.39厘米。据测定,一年中每亩耕地由于水土流失而损失的有机质约192斤,全氮
First, the basic situation My county is located in southern Ningxia, a comprehensive management of loess plateau area. The county covers an area of 4715000 acres of land (of which 2820000 acres of arable land), 1558000 acres of slope above, occupy the total area of 33%. Soil erosion is relatively serious, the average annual soil erosion modulus of 3952 tons / km 2, the total annual erosion of 12.42 million tons, annual average loss of surface soil thickness of 0.39 cm. It is determined that the loss of organic matter per acre of arable land due to soil erosion in the year about 192 pounds, total nitrogen