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陇南浅山半干旱区,属黄土丘陡沟壑地区第三付区。其气候特点是:四十年平均年降雨量536.2毫米,但年变幅比较大,最多772.2毫米,最少324.5毫米,降水丰年为旱年的2.4倍。季节分布也不均,七、八、九三个月降雨量占年雨量的53％;冬季,春季降雨量只占17％。虽然秋季雨量占年雨量一半以上,但多以大雨、暴雨出现,因此,在多雨季节,也常发生伏旱。冬春雨雪稀少,加上春季风大加速了地面蒸发,易显春旱。因此,这一地区素有“三年两头旱”和“十年九旱”之说。该区年平均温度为11.4℃,一月份在0～-8℃之间,绝对最低为-19℃;七月份温度在21℃～26℃之间,绝时最高为38～39℃,春季日温差多至
Longnan semi-arid semi-arid area, a loess hill steep gully area third paid area. Its climatic characteristics are: average annual rainfall of 536.2 millimeters in 40 years, but the annual amplitude is relatively large, up to 772.2 millimeters, the least 324.5 millimeters, rainfall year of harvest is 2.4 times of dry year. Seasonal distribution is also uneven, seven, eight, nine three months of rainfall accounted for 53% of annual rainfall; winter, spring rainfall accounted for only 17%. Although autumn rainfall accounts for more than half of the annual rainfall, it is mostly caused by heavy rain and heavy rain. Therefore, during the rainy season, drought often occurs. Rare snow in winter and spring, plus the spring wind accelerated the ground evaporation, easy to show spring drought. Therefore, the region is said to have “three dry spells in three years” and “nine dry years in ten years”. The average annual temperature in this area is 11.4 ℃. The monthly average temperature is between 0 and -8 ℃ in January, and the absolute minimum is -19 ℃. In July, the temperature is between 21 ℃ and 26 ℃, and the absolute maximum is 38 and 39 ℃ in spring. As much as the temperature difference