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安康专区位于北纬32°37′——33°54′,东经108°05′——110°20′之间,在陕西省之东南部,东邻湖北,南接四川,西与汉中专区之洋县、西乡、鎭巴为界,北与长安、及商雒专区之鎭安县毗连,包括有石泉、安康、紫阳、平利、洵阳、白河等六县,面积有19,472平方公里。 本区为复背斜组成的山地,北有秦岭,南有巴山,中有汉江横贯,形成两边高起中间低下的槽状地形,区内地质,除安康盆地及汉江和其支流沿岸为第四纪红色粘土外,其余均为古生代的片岩、千枚岩及变质石灰岩等所组成的石质山地;由于长期流水侵蚀的结果,本区沟壑纵横,坡陡谷深,水土流失十分严重。根据1957年水利部门的统计,全区水土流失的面积约有7,500平方公里,占总土地面积的38.5％,每年输入汉江的泥沙根据1956年的统计即有3,040万吨。 这个土壤侵蚀的数字,如按其中含有0.06％的氮
Ankang Prefecture is located in the north latitude 32 ° 37 ’- 33 ° 54’, east longitude 108 ° 05 ’- 110 ° 20’, in the southeast of Shaanxi Province, east of Hubei Province, south of Sichuan, west and the Hanzhong Ocean It covers an area of 19,472 square kilometers with six counties including Shiquan, Ankang, Ziyang, Pingli, Xingyang and Shirakawa. The area is composed of complex anticlinal anticline mountain, north of Qinling, Bashan in the south, there Hanjiang River traversal, the formation of trough-shaped topography on both sides of the high low, the area geology, in addition to the Ankang Basin and the Han River and its tributaries along the coast for the fourth Because of the result of long-term flowing water erosion, the ravines in this area are vertical and horizontal, with steep slopes and deep valleys, soil erosion is very serious. According to the statistics of the department of water conservancy in 1957, the area of water and soil loss in the whole region is about 7,500 km 2, accounting for 38.5% of the total land area. According to the 1956 statistics, there are 30.4 million tons of sediment transported to the Han River every year. The number of soil erosion, if it contains 0.06% of nitrogen