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陕北的榆林和延安两地区２５个县（市），面积８００９１．８８ｋｍ２。水土流失强烈为最突出的特征。土壤侵蚀的特点是：（１）现代侵蚀是古代多期侵蚀轮回基础上的继承和叠加。（２）水土流失面积大，侵蚀产沙强度高。水土流失面积占７６％，年输沙量６．９６亿ｔ，平均侵蚀产沙模数为９３７０ｔ／（ｋｍ２·ａ），沟谷密度大，平均密度３．０６ｋｍ／ｋｍ２。沟谷面积占４５％～５５％。（３）侵蚀类型、方式和强度垂直分布和水平地带分异规律明显。（４）侵蚀强度与生态环境因素密切相关。（５）工矿城镇建设直接增加水土流失的现象加剧，必须采取综合措施治理水土流失。
There are 25 counties (cities) in Yulin and Yan’an areas in northern Shaanxi with an area of 80091.88km2. Strong soil erosion is the most prominent feature. Soil erosion is characterized by: (1) modern erosion is inherited and superimposed on the basis of ancient multi-period erosion cycles. (2) Large area of soil erosion, high erosion and sediment intensity. Soil erosion area accounts for 76%, annual sediment discharge 696 million tons, the average erosion and sediment yield modulus 9370t / (km2 · a), gutter density, the average density of 3.06km / km2. Valley area accounted for 45% ~ 55%. (3) Erosion types, patterns and intensity vertical distribution and horizontal zone differentiation law obviously. (4) The erosion intensity is closely related to the ecological environment. (5) The phenomenon of directly increasing water and soil loss in the construction of industrial and mining towns and cities aggravates. Therefore, comprehensive measures must be taken to control soil and water loss.