长期膜下滴灌棉田土壤水盐空间分布特征研究

Study on spatial distribution characteristics of soil moisture and salinity in cotton field for long time drip irrigation under film

为分析播种前膜下滴灌棉田土壤不同深度水分和盐分的分布特征,对1998年开始利用膜下滴灌种植技术的棉田进行大规模网格取土,主要分析了棉田土壤水盐空间分布特征。研究结果表明:在生育期初播种前,棉田土壤0~5、5~20、20~40、40~60、60~80及80~100 cm对应土层中,水分变异系数小于盐分变异系数,且都属于中等变异性;土壤各层水分和盐分含量总体都呈现出表层土壤水分和盐分含量较低,深层土壤水分和盐分含量较高的分布规律;在0~100 cm土层中,随着深度增加,水分和盐分含量呈现出先增大后减小的趋势;设置排盐沟,能够使土壤盐分向排盐沟运移,有助于棉田改良。

In order to analyze the distribution characteristics of soil moisture and salinity at different depths before sowing in cotton field of drip irrigation under film,The paper a lot of samples got by the way of large scale grid in cotton field where cottons were cultivated by use of drip irrigation under film since1998. It primarily analyzed the spatial distribution characteristics of soil moisture and salinity in field. The results showed that before sowing,in the soil layers of 0- 5,5- 20,20- 40,40- 60,60- 80 and 80- 100 cm,the variation coefficient moisture is less than that of corresponding salinity,and both belong to the moderate variability; soil moisture and salinity in each layer generally present low content on surface and high in deep; among the soil layer of 0- 100 cm,with the increase of depth,the moisture and salinity content show the trend of increase first and that of decrease then; setting ditch of salt drainage can make soil salinity migrate to the direction of salt drainage ditch and improve cotton field.