棉花微咸水膜下滴灌灌溉制度的研究

Study on irrigation scheduling of cotton under mulch drip irrigation with brackish water

为寻求微咸水膜下滴灌的最优灌溉制度,利用2008和2009年田间试验结果,从棉花生长和产量的角度出发,分析11种灌溉处理各生育期的变化情况。测定了叶面积、干物质质量、棉花产量、土壤盐分等指标。结果表明:灌溉水量越大,棉花营养生长部分生长越快,生长时间越长;灌水盐分越高,盐分胁迫使生殖生长部分所占比例越大,越易衰老;试验区内灌溉定额3750m3/hm2(微咸水80%,淡水20%)的轮灌处理,2008年棉花产量达到5190kg/hm2,接近仅灌淡水5250m3/hm2处理(5205kg/hm2),该轮灌处理2008年总盐为负增长(-0.95g/kg),2009年试验结果有力验证了该灌溉制度的节水增产、保护土壤环境的优越性。

In order to obtain the optimal irrigation program of mulch drip irrigation with brackish groundwater,the growth and yield of cotton under 11 different irrigation treatments in 2008 and 2009 were analyzed in different reproductive periods.In this paper,the leaf area,dry matter,cotton yield and salt of soil were measured by WDY-500A micro-electron leaf area,oven drying method,artificial method,atomic absorption spectrometer and titration,respectively.These results showed the cotton vegetative growth became faster with increase of irrigation water;the proportion of reproductive growth was greater and easier to become old when the salinity of irrigation was higher.These results also indicated that rotation irrigation system（3 750 m3/hm2,80% brackish water and 20% fresh water） was the optimal one,whose yield reached 5 190 kg/hm2.Meanwhile,in 2008 the rotation irrigation system attained a negative growth（-0.95 g/kg） of total salt.And results of 2009 strongly demonstrated the superiority of the irrigation system.This rotation irrigation system will realize water conservation,increasing yield effectively and protection of soil environment.