膜下滴灌条件下棉花年际需水量变化试验分析

Experimental analysis of annual water requirements change of cotton by drip irrigation under film

为探索新疆准噶尔盆地南缘区膜下滴灌棉花年际需水量、水分生产率、作物系数、生长动态等变化,连续3年开展了灌溉试验,研究棉花耗水规律及气象因素对耗水规律的影响。结果表明:棉花生育期总耗水量随灌水量增加而增大,各处理(处理T1、T2、T3、T4分别为300、375、450、525 m^3·hm^(-2))耗水量差异显著,耗水量在343~625 mm之间;不同年份气象要素中气温对棉花生育阶段需水量影响最大;棉花皮棉产量与全生育期灌水量呈二次抛物线关系,水分生产率随灌水量的增加而降低,其值范围0.65~0.34 kg·m^(-3);不同时期棉花作物系数大小表现为:开花~吐絮>现蕾~开花>吐絮~收花>出苗~现蕾>播种~出苗,全生育期作物系数呈现单峰值变化,峰值出现在开花~吐絮期;生育期内棉花株高、叶面积指数和叶绿素均呈先增后减,最后保持平稳的趋势。不同处理棉花株高和叶面积指数与灌水量呈正比关系,随灌水量增大而增加,全生育期内株高和叶面积指数峰值出现在花铃期,叶绿素峰值出现在蕾期。

In order to explore the changes of annual water requirements,water productivity,crop coefficient,growth dynamic of cotton by drip irrigation under film in southern margin of the Zhungaer Basin,Xinjiang,continuously carried out 3 years experiment,to research and analyze the rule of cotton water consumption and its response to meteorological factors. The results showed that: The total water consumption in cotton growing period was increased with increasing of irrigation quantity,the water consumption differences was significant for each treatment( T1,T2,T3 and T4 were 300,375,450 m^3·hm^(-2) and 525 m^3·hm^(-2),respectively),the water consumption was between 343 ~ 625 mm. Among the meteorological factors of different years,the temperature has the greatest impact on the cotton water requirements in growing period. The ginned cotton yield with the irrigation quantity in whole growing period assumed quadratic parabola relation. The WUE was decreased with increase of irrigation amount,its value range in 0.65 ~ 0.34 kg·m^(-3). The size of crop coefficient was expressed as lowering ~ boll opening>budding>flowering > boll opening ~ receiving flowers > seedling ~ squaring > seeding ~ seedling emergence. The crop coefficients in whole growth period were appeared a single peak change and peak value was appeared in flowering ~boll opening stage. In growth period of cotton,the plant height,leaf area index and chlorophyll,the whole trend was increase at first,and then decrease,ultimately remained smooth and steady. Under different treatments,the plant height and leaf area index was proportional to irrigation amount,increased with the increase of irrigations water. The peak value of plant height and leaf area index was appeared in the blossing and boll-forming stage and the peak value of the chlorophyll was appeared in the bud stage.