棉花膜下滴灌盐分动态及平衡研究

在南疆气候条件下．研究了膜下滴灌盐分动态变化及平衡．结果表明：在南疆，棉花苗期时，土壤盐分开始分区，盐分在膜间0～40cm强烈聚集，膜下盐分变化不大，而且在覆膜的作用下发生侧向运移，移向膜间，加剧了膜间的盐分累积；棉花生育期结束后．土壤0～60cm盐分都有增加．在膜间0～20cm盐分强烈累积；灌水量为345mm的处理盐分增加明显，积盐率高达．94．5％，其增加的盐分主要来自下边界土壤水分上行所带来的盐分，占盐分增加量的57％．而灌水量505mm处理增加的盐分主要来自灌溉水所携带的盐分，占81％．若不考虑灌溉水的矿化度，膜下滴灌土壤盐分的积盐率只有13．8％。

Study on Dynamic and Balance of Salt for Cotton under Plastic Mulch in South Xinjiang

The field experiments were conducted at Yuli county of Xinjiang in 2004 from Apr. to Oct. It is tound that in south Xinjiang, in cotton seedling stage, because of covering the function of the membrane, the salt in soil begin the dividing area, the salt is gathered strongly in 0-20 cm in uncovered area, and the salt of soil under film had taken place side direction transport and move to the uncovered area which have aggravated the salt of uncovered area even more. After cotton growing stage finishing, the salt of 0- 60 cm layers have increased, and assembled sharply in the uncovered area in 0-20 cm layers; The salt of lower water treats enhanced greater,the ration of salt accumulation reached 94.5%,which mainly come from the salt that moving up water carried on, up to 57 % of increased salt,and the salt increased of higher irrigation treats mainly come from the salt irrigation water carrying on, was about 81%, so adding irrigating water can decreased the accumulation of salt in a certain extent.