A field experiment was conducted in the winter wheat-summer maize rotation system in low plain of Northern Shandong province to study the effect of supplementary irrigation with slight salt water and straw returned to field on soil salt content dynamic and grain yield. The results indicated that 1 ~2 times irrigation in wheat growth stage with 2 ~4 g/L salt content water combined straw returned to field had no significant influence on grain yield and soil salt accumulation. Without straw returning, 2 times irrigation with 4 g/L salt water made a significant soil salt accumulation, harmed the wheat growth and decreased the wheat grain yield obviously. After straw returned, the soil plough layer became loose, bulk density improved and soil non-capillary porosity increased significantly. All these could effectively inhibit salt accumulation and make the crop root grow better in soil plough layer. The agricultural strategies of irrigation altering with non-salt water and slight salt water, straw returned to field and leaching top soil salt with summer rain could make the soil profile salt content get balance yearly. Which ensured the safety and high efficiency of supplementary irrigation with slight salt water.%通过田间小区试验,研究了鲁北低平原地区小麦、玉米两熟制下微咸水补灌对土壤盐分与作物产量的影响以及玉米秸秆还田对微咸水灌溉土壤盐分的调控作用.结果表明:麦季利用2 ～4 g/L矿化度的微咸水补灌1～2次,秸秆还田的小区没有发生明显积盐现象,对粮食产量基本无影响.用4 g/L矿化度的微咸水连续补灌2次,没有秸秆还田的小区土壤耕层明显积盐,对小麦生长产生明显危害并影响产量.秸秆还田后的土壤耕层结构疏松,容重降低,非毛管孔隙度显著增加,能有效抑制土壤盐分表聚,使作物主要根系活动层保持较低盐分水平而不影响作物正常生长.利用咸淡水轮灌压盐、秸秆还田抑盐、雨季降水淋盐综合措施,能使土壤盐分保持周年平衡,保证了微咸水补灌的安全高效.
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