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一、自然概况天水地区位于东经103°53′至106°43′,北纬33°31′至11′之间,地处陇中黄土高原南部和陇南山地。其北以秦岭为界,分属渭河,嘉陵江两大水系。气候属温暖带湿润和温带半干旱性气候。年平均降雨量在460～700毫米之间,多集中于七、八、九月。年平均温度5～10℃,无霜期100～220天,海拔700～3941米,有40％左右的面积处于海拔1700米以下。森
I. Natural Overview Tianshui is located between 103 ° 53 ’and 106 ° 43’ East Longitude and 33 ° 31 ’to 11’ North Latitude, and is located in the south of Longzhong Loess Plateau and Longnan Mountains. The north of the Qinling Mountains as the boundary, belonging to the Weihe River, Jialing River two major water systems. The climate is warm and humid and temperate semi-arid climate. The average annual rainfall between 460 ~ 700 mm, mostly concentrated in seven, eight, September. The annual average temperature of 5 ~ 10 ℃, frost-free period of 100 to 220 days, 700 to 3941 meters above sea level, about 40% of the area at an elevation of 1700 meters below. Sen