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(一)榆林县位于陕西北部,地处毛乌素沙漠南缘和无定河中游,界于北纬37°49′～38°301′东经108°56′～110°24′之间。东西长128公里,南北宽124公里,总土地面积6834.85公里~2。据历史资料记载,隋代以前,这里森林茂密、水草丰盛、原阜平阔、景物宜人,唐代以后,特别是明、清以来至民国期间,由于大量滥垦滥伐、毁林毁草,加之风力和流水的剥蚀作用,引起土地沙化和水土流失,从而塑造成县境西北部沙丘绵延不断的“人造沙漠”和东南部地形切割破碎的童山秃岭,构成了现今“七沙”、“二山”、“一
(1) Yulin County is located in the northern part of Shaanxi Province. It is located in the southern margin of the Mu Us Desert and the middle reaches of the Wudinghe River. It is between 108 ° 56 ’and 110 ° 24’ long latitude 37 ° 49 ’~ 38 ° 301’. Things 128 km long, north-south width of 124 km, the total land area of 6834.85 km ~ 2. According to historical records, before the Sui Dynasty, the area was rich in forests, rich in water and plants, the original Fu-Ping-Kuo and pleasant scenery. Since the Tang Dynasty, especially since the Ming and Qing Dynasties to the Republic of China, In addition, the erosion of wind and water leads to the desertification of soil and the erosion of water and soil, thus shaping the continuous “artificial desert” of sand dunes in the northwestern part of the county and the bald mountain of Tongshan baldness in the southeastern terrain, forming the current “Qisha” and “ Two Mountains ”," One