干旱区垄膜沟灌条件下土壤水盐空间分布特征研究

研究了垄膜沟灌条件下,不同灌溉定额下土壤水盐空间分布特征。结果表明,土壤含水率的时空分布受灌水次数和灌水定额的影响。灌溉期,在垂直方向上沟底土壤含水率较垄顶明显增加。在非灌溉期,由于强烈的蒸发蒸腾作用,垄顶土壤含水率持续降低,含水率阶段性变化明显。土壤盐分空间分布随土壤含水率的变化而变化,在灌溉期,沟底土壤脱盐深度随灌溉定额的增加呈增加的趋势。在非灌溉期,垄顶在作物生育期均发生积盐现象,且垄顶表层土壤盐分累积量高于沟底表层土壤。

Distributions of Soil Moisture and Salinity under Ridge-tillage and Furrow Irrigation with Film Mulch in an Arid Area

Field experiment was conducted to study the spatial distributions of soil moisture and salinity under ridge tillage and furrow irrigation with film mulch in an arid area.The results showed that the spatio-temporal distributions of soil moisture depend on irrigation frequency and the amount of irrigation.During irrigation,water content in soil underneath the furrow in the depth of 0～100 cm is higher than that underneath the ridge.After irrigation,water content in soil within the ridge dropped quickly due to evapotranspiration.The spatial distribution of salinity depends on soil water movement.During irrigation,thesize of the desalination zone increased with the amount of irrigation,while after irrigation salt accumulated insoil during the period of crop growing,especially within the ridge surface.