灌溉方法对蔬菜大棚土壤盐渍化及酸化的影响

Effects of Different Irrigation Patterns on Soil Salinity and Acidification in Vegetable Greenhouse

为了探明蔬菜大棚灌溉措施对土壤盐分积累特征的影响，以连续13年采用渗灌、滴灌和沟灌方式栽培番茄的蔬菜大棚土壤为材料，分层采集0～60cm深度的土壤样品，测定土壤盐分含量及其离子组成、pH的剖面分布，对不同层次土壤盐渍化及酸化状况进行了分析，研究灌溉方法对土壤盐分积累特征及pH的影响。结果表明，土壤全盐含量在所有灌溉方法中均呈现出明显的表聚现象，随着土层的加深而减少；各处理间土壤全盐含量在0～20cm土层差异显著，沟灌盐分含量最高，其次为渗灌，滴灌最低；土壤中水溶性阴离子以SOi和NO3 为主，阳离子以Ca”为主。3种灌溉处理土壤PH均以表层最低，随着土层加深而迅速升高；灌溉处理间0～30cm土层pH差异明显，其大小顺序为滴灌〉渗灌〉沟灌；蔬菜大棚土壤的盐分积累是导致土壤PH下降的重要原因。长期使用滴灌比沟灌和渗灌更有利于防止土壤盐分积累与酸化。

The salt content, ion composition, pH profile distribution, salinity and acidification of different soil samples within 0～60 cm depth from a tomato greenhouse separately irrigated by infiltration, drop and furrow irrigation patterns for continuous 13 years were analyzed to study the effect of different irrigation patterns on salt accumulation in soil of the vegetable greenhouse. The results showed that total salt content of all tested treatments appeared the obvious surface assembly and decreased with increase of soil depth. Total soil salt content of soil samples within 0 ～ 20 cm soil layer was significant difference between different treatments and the salt content under the furrow irrigation pattern was the highest, followed by infiltration and drop irrigation pattern. Main water solubility negative ion and positive ion were SO214 , NOaand Ca2＋. The soil pH of three treatments rose rapid with increase of soil layer depth. pH of soil samples with 0～30 cm soil layer was significant difference between different treatments and the order was drop irrigation〉infiltration irrigation〉furrow irrigation. The salt accumulation is the important reason for soil pH decline in a vegetable greenhouse. Therefore, the drop irrigation pattern is beneficial to preventing soil salt accumulation and acidification compared with infiltration and furrow irrigation patterns in a vegetable greenhouse.