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一、概述大洼灌区位于辽宁南部双台河大辽河之间,频临渤海,土地总面积216万亩,属滨海盐渍土区,百分之九十以上为不同程度的盐渍土,非盐渍土仅占10%。地势低平,海拔为2.5—3.6来,由北东向南西呈1/15,000至1/20,000坡度微倾斜。地下水埋藏较浅,枯水季节1.2～20米,且矿化度高。年雨量650—750毫米,55%以上集中在7、8两月。无霜期165—180天,积温可达3456度,日照1510小时,适
I. Overview Dawa irrigation area is located in the southern Liaoning between the Liaohe, Shuangtaihe, frequent the Bohai Sea, the total land area of 2.16 million mu, is a coastal saline soil area, more than ninety percent for varying degrees of saline soil, non Saline soil only accounts for 10%. Low-lying terrain, 2.5-3.6 above sea level, slightly inclined from 1 / 15,000 to 1 / 20,000 slope from north-east to west-west. Groundwater buried shallow, dry season 1.2 to 20 meters, and high salinity. Annual rainfall of 650-750 mm, 55% concentrated in the 7,8 two months. 165-180 days frost-free period, the accumulated temperature up to 3456 degrees, sunshine 1510 hours, suitable