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有机旱农主要是在培肥地力的基础上,依靠有限的天然降水,采取抗旱栽培的农业生产。在干旱地区,实行有机旱农耕作,是农业增产的根本途径。发展有机旱农耕作的重要性我县气候干旱,年平均降雨量479.4毫米,但变率大,时空分布极不均匀。据1958—1979年的21年统计,有五年雨量不足400毫米,超过600毫米的只有三年。特大旱年的1973年降雨量仅为308.3毫米。降雨多集中在七、八、九三个月,占年降雨量的64.7％。年蒸发量1493毫米,是年降雨量的三倍多。旱灾须繁,春早几乎年年有。1973年特大干旱,粮食亩产74斤比
Organic dry agriculture is mainly based on the fertility of fertility, rely on limited natural precipitation, to take drought-resistant cultivation of agricultural production. In dry areas, the implementation of organic dry farming is the fundamental way for agricultural production. The importance of developing organic dry farming Our county arid climate, the average annual rainfall of 479.4 mm, but the rate of change, very uneven distribution of space and time. According to the 21-year statistics of 1958-1979, there were five years of rainfall of less than 400 millimeters and more than 600 millimeters for only three years. In 1973, the rainfall was only 308.3 millimeters. Rainfall concentrated in seven, eight, nine three months, accounting for 64.7% of annual rainfall. The annual evaporation is 1,493 mm, more than three times the annual rainfall. Drought need to be complicated, spring almost every year. In 1973, a serious drought, grain yield 74 pounds per mu