冬季咸水结冰灌溉后土壤水盐运移规律的初步研究

在河北省海兴县对冬季利用苦咸水结冰灌溉盐碱地进行了大田试验。2005年冬季以试验区地下苦咸水(15 g/L),采用3种灌溉水量(90,135,180 mm)对盐碱地进行结冰灌溉,以不作处理的小区为对照(CK)。结果表明,由于冰层对土体冻融过程的抑制和冰层融化时发生水盐分离而产生的淡水对表层土壤盐分的淋洗的双重作用,次年春季处理小区0~10 cm土层土壤脱盐效果明显,3个处理的脱盐率分别为13.1%,74.0%,80.8%,180 mm灌溉水量处理效果最好;而CK小区的表层土壤表现为积盐,积盐率为39.4%。春季冰层融化后大水量处理0~100 cm土壤的含盐量也明显小于CK。

A Primary Study on the Reclamation of Coastal Saline Soil with Freezing Irrigation of Saline Water in Winter

A field experiment was conducted to investigate the effect of freezing irrigation with saline water in winter on the dynamics of soil salinity and moisture in coastal saline soil.Four irrigation amounts(0,90,135 and 180 mm) with the shallow brackish groundwater(15 g/L) were exploited in this experiment in winter.Results showed that top soil layer was well desalinized with freezing irrigation in the next spring when soil freezing layer thawed.The desalinizing ratio is 12.7%,73.8% and 80.9% in 90,135 and 180 mm irrigation treatments,respectively.However the no irrigation treatment showed intensive salinization in spring.The possible reason is that the ice layer restrains the freezing and thawing process of the saline soil and the leaching effect of fresh water produced from the melted saline ice.