南疆膜下滴灌棉花耗水规律以及灌溉制度研究

2004年在南疆尉犁县进行了棉花膜下滴灌耗水规律以及灌溉制度的研究,通过设置三个灌水处理:345 mm、420 mm、505 mm,并连续监测每次灌前棉花全生育期土壤含水量变化,得出以下结论:在花期(7月4日)滴灌定额45 mm,灌水只能影响到土壤0~40 cm,灌后第一天,土壤水分损失可达到20 mm;灌后四天,0~40 cm含水量已降至60%以下,棉花已受到水分胁迫。在南疆,在充分满足棉花对水分需求的条件下,膜下滴灌棉花耗水量为625 mm,505 mm的灌溉量可满足棉花对水分的需求。根据实验的灌水安排以及棉花各生育阶段的耗水率,南疆膜下滴灌棉花的灌溉制度为:蕾期每次灌水定额35 mm,每5天灌一次;花铃期每次灌水定额为50 mm,7天灌一次,盛铃期后,灌水定额逐渐降低至35 mm。

Water consumption characteristics and scheduling of drip irrigation under plastic film for cotton in south Xinjiang

The scheduling of drip irrigation was studied in Yuli County,Kuerle in 2004 with three irrigation treatments: 345 mm,420 mm and 505 mm.It was found that,when the irrigation ration was 45 mm in florescence stage,the soil moisture in 0~40 cm layer increased sharply to 90%;after one day it dropped to 70%,and the water loss was up to 20 mm;after four days it dropped to 60%,and the crop was affected by water stress.The water demand of cotton is about 625 mm for drip irrigation under plastic film in south Xinjiang.According to the arrangement of irrigation and water demand of cotton,the rational irrigation scheduling is: 40 mm for every four days in bud stage;50 mm for every seven days in florescence stage;and 35 mm for every seven days after flourishing boll stage.