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一、自然特点渭北旱原位于我区北部,属黄土高原丘陵沟壑区。该区土地面积广阔,沟壑纵横,丘陵起伏,林草面积稀少,干旱缺雨,水土流失严重。地貌分为北部低山区和南部高原沟壑区,形成北高南低台梯形。地质年代属新生界第四系,一部分属中生界,少部分属太古界。北部低山丘陵区一带为纸坊群沙岩和石英岩地质,由白水至韩城为海陆交互相和含煤碎屑岩沉积,构成渭北“黑腰带”。土壤为褐土。植物属暖温带落叶阔叶林带。北部沟壑区塑原侵蚀强烈,侵蚀模数为4715吨/公里~2,水土流失面积为6350吨/公里~2。面积在100公里~2以上的沟壑有11条,50～100公里~2的有12条,30～50公里~2的有
First, the natural characteristics Weibei drylands are located in the northern part of our region, is a hilly and gully area of the Loess Plateau. The area of land is vast, ravines aspect, hilly, sparse forest and grass area, drought and rain, soil erosion is serious. Landforms are divided into northern low mountainous areas and the southern gully area, the formation of North High South low trapezoid. Geological age belongs to Cenozoic Quaternary, a part of Mesozoic, a small part of the Archean. The hilly area in the northern part is the paper sandstone and quartzite of the Zafangfang Group. From Baishui to Hancheng, there are the sea-land interaction facies and coal-bearing clastic sediments, forming the “black belt” of Weibei. The soil is cinnamon. Plants are warm temperate deciduous broad-leaved forest belt. In the northern gully area plastic primary erosions are strong with an erosion modulus of 4715 t / km ~ 2 and an area of 6350 t / km ~ 2. There are 11 gullys with an area of 100 km ~ 2 or more, 12 of 50 ~ 100 km ~ 2, 30 ~ 50 km ~ 2 of