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(一) 甘肃地处西北高原,位于祖国中部,境内多山,拔海高度一般在一千五百公尺以上。土地总面积四十六万平方公里。现有耕地6,238万亩(其中山地占70％左右),分属于黄河、长江、内陆河三个流域。主要支流有三十余条,全年径流总量约六百亿公方,年降雨量平均三百公厘左右。无霜期120—220天。历史上多旱灾,水土流失严重。按地形和土壤侵蚀情况,分为黄土高原沟壑区,一般丘陵沟壑区、干旱丘陵沟壑区、土石山区、
(1) Located in the northwestern plateau of Gansu, Gansu is located in the central part of the motherland, with mountainous areas and altitude of more than 1,500 meters above sea level. The total land area of 460,000 square kilometers. The existing 62,380,000 acres of arable land (of which about 70% of the mountain), belonging to the Yellow River, Yangtze River, inland river three basins. There are more than 30 major tributaries, with a total annual runoff of about 60 billion square kilometers and an average annual rainfall of about 300 mm. Frost-free period 120-220 days. More drought in history, soil erosion is serious. According to the topography and soil erosion, it is divided into the gully area of the Loess Plateau, the general hilly and gully areas, the gully areas of arid hills, the rocky mountainous areas,