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兰州市辖三县(永登、榆中和皋兰)五区,位于祁连山的东延和陇西黄土高原盆地西北部,境内大部分地区属于黄土高原丘陵沟壑区,地形呈东北高,西南低,海拨一般均在1400米以上。气候干燥,雨量偏少,且集中在7～8两个月。年平均降水量为324.85毫米。水源主要来自黄河,流经市区长达152公里,河面宽150～1000米,流量一般为1070米~3/秒,多年平均径流量331.1亿米~3。全市山地面积占总面积的65%以上。现已发展水地82万亩。主要是种植粮食作物小麦,一年一茬。因降水量少,每到夏灌高峰时,
Lanzhou City, under the jurisdiction of the three counties (Yongdeng, Yuzhong and Gaolan) five districts, located in the Qilian Mountains and Longxi Loess Plateau northwestern basin, most of the territory belongs to the hilly and gully region of the Loess Plateau, northeastern high terrain, low in the southwest, Generally above 1400 meters above sea level. Dry climate, less rainfall, and concentrated in 7 to 8 two months. The average annual precipitation is 324.85 mm. The main source of water from the Yellow River, flowing through the urban 152 km long, the river width of 150 to 1000 meters, the flow is generally 1070 m ~ 3 / sec, the average annual runoff of 33.1 billion m3. The city’s mountainous area accounted for more than 65% of the total area. Has now developed 820000 acres of water. Mainly the cultivation of food crops, wheat, a year. Due to less precipitation, each summer irrigation peak,