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我省中部干旱区纵然有黄河、洮河、湟水、庄浪河、祖历河等河流,但这些河流除黄河、洮河外,其余河流大多是季节性河流,流量随季节变动很大。7—9月雨季期间,每遇大雨或暴雨时,由于山上无林木植被截留雨水,山水汇集于河涧,季节性河水突然暴涨,淹没河川农田,雨后河水又迅速退落成溪,很快干涸,农业利用经济效益很低。本区的海拔高度比较高,除高山外大多在1500—2200公尺,河川谷地1300—1800公尺,具有山塬气候特色。一个地区的农业气候之优劣,是热量、水分、光照、生长期以及灾害性气象的危害程度等诸因素之综合结果。本区年平均气温除了华家岭、马衔山等高寒山区在4℃以下和东南部的武山、甘谷、秦安县一带为8—10℃外,区内其他地区为6—9℃;海拔1550公尺以下的河
Even in the central arid region of our province, there are rivers such as the Yellow River, the Bahe River, the Huangshui River, the Zhuanglang River and the Zulian River, except for the Yellow River and the Bahe River. Most of the remaining rivers are seasonal rivers, and the flow rate varies greatly with the seasons. During the rainy season from July to September, every rainstorm or rainstorm rains, rainwater is trapped in the forest without any vegetation on the hillside. Rivers and streams flood into the river. Suddenly, seasonal river water surges and submerges the river farmland. After the rain, the river quickly recedes into a river and dries up quickly , Agricultural use of low economic benefits. The elevation of this area is relatively high, with the exception of the mountains mostly in the 1500-2200 meters, 1300-800 meters in the valley of the valley, with mountain plateau climate characteristics. The advantages and disadvantages of an agricultural climate in a region are the result of a combination of factors such as calorie, moisture, light, growing season, and the extent of damage from a disastrous weather. The annual average temperature in this area is 8 ℃ except 8 ℃ in Wulian, Gange and Qinan counties in alpine mountainous areas such as Huajialing and Majian Mountain, and below 6- Meters below the river