膜下滴灌条件下膜间不同处理对土壤水盐运移的影响

目的]寻求合理的膜间土壤盐分累积控制方法,为指导盐碱地田间调控提供科学依据。方法]采用覆秸秆,铺砂,喷施高分子化合物PAM,压实等方式对膜间裸地进行处理,对比分析各种处理措施的功效。结果](1)各处理都能不同程度的减小膜间的水分蒸发量,起到保水作用。其中,在试验期间,覆秸秆的蒸发量为0.11cm,铺砂子蒸发量为0.34cm,喷施PAM为0.59cm,压实为1.55cm,而对照为2.32cm。(2)各处理都能提高膜间和覆膜窄行的土壤含水量。在覆膜窄行深度为10cm处,覆秸秆的土壤含水量相对降低率为47%,铺砂土的壤含水量为45%,施PAM的土壤含水量为56%,压实的土壤含水量为64%,对照为土壤含水量77%。(3)减小盐分在作物根层的积累。在覆膜窄行深度为10cm处,覆秸秆的相对脱盐率为3%,铺砂的相对脱盐率为2%,施用PAM的相对脱盐率为0%,压实的相对脱盐率为-16%,而对照的相对脱盐率为-28%。结论]采用膜间处理能够减小水分散失和盐分在根层的积累,其中覆秸秆的功效最好。

Effects of Different Intermembrance Treatments on Soil Water and Salt Transport Through Drip Irrigation Under Film

Objective] To seek a reasonable method in soil salinity accumulation controlling between membrane, in order to provide the basis for control the salt accumulation on soil surface.Methods] Different intermembrance treatments were employed, including:straw covering, laying sand, PAM(polyacrylamide) spraying, compacting and controlled treatment, to analyze the efficacy of the treatment measures.Results] (1) All the treatments could reduce the moisture evaporation. The evaporation in straw covered, sand spread, spraying PAM, compacting, and the controlled treatment was 0.11, 0.34, 0.59, 1.55 and 2.32 cm, respectively.(2) All the treatments could reduce the moisture evaporation of membrane narrow row, and improve soil moisture of membrane narrow line. At 10 cm depth of the narrow line, the relative reduction of soil moisture in straw covered, laying sand, spraying PAM, compacting, and the controlled treatment was 47%, 45%, 56%, 64% and 77%, respectively.(3) All the treatments reduced salt accumulation in the root zone of the crop. At 10 cm depth of the narrow line, the relative desalination in straw covered, laying sand, spraying PAM, compacting and the controlled treatment was 3%, 2%, 0%,-16% and-28%, respectively.Conclusion] Applying intermembranes treatments can reduce the water loss and salt accumulation in the root zone. Straw covering is the best methods in reducing soil water loss and salt accumulation in the root zone.