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五台县李家庄小流域,属海河二级支流,面积13km~2,海拔655～1598m,流域内岩石主要由二迭纪石灰岩构成,夹有少量花岗岩、片麻岩,石山区面积占总面积的67％。土壤主要由亚矿土淤积褐土组成,土层厚度5～50cm,可耕地面积618亩,占总面积3.2％,沟壑密度2km/km~2,属典型的石灰岩石质山区,山高坡陡,石多土薄的地形条件,加之历史上的乱采滥伐,流域内乔木林寥寥无几,地面植被多为天然草灌,也因过渡放牧生长不良。流域内水蚀、重力侵蚀严重,年土壤侵蚀模数800～1300t/km~2,强烈的面蚀使贫瘠的土地资源遭到破坏,沟岸泻流,崩塌阻塞河道,淤积下游农田,600亩河滩乱石滚滚成为不毛之地。
The Lijiazhuang small watershed in Wutai County belongs to the second tributary of the Haihe River with an area of 13km ~ 2 and an elevation of 655 ~ 1598m. The rocks in the basin are mainly composed of Permian limestone with a small amount of granite, gneiss and rocky mountainous area accounting for the total area 67%. The soil is mainly composed of alluvial soil silt cinnamon soil layer thickness of 5 ~ 50cm, 618 acres of arable land, the total area of 3.2%, gully density of 2km / km ~ 2, is a typical limestone rocky mountainous area, Stone more soil conditions, coupled with the history of indiscriminate deforestation, very few trees within the basin, the ground vegetation is mostly natural grass irrigation, but also due to poor transitional grazing growth. In the basin, water erosion and gravitational erosion are serious. The annual soil erosion modulus is 800 ~ 1300t / km ~ 2. Severe erosion leads to the destruction of barren land resources, ditches and bankruptcies, blocked river channels, siltation of downstream farmland, Rocks become barren.