摘要
为探索干旱区膜下滴灌条件下土壤水盐定向迁移机制和地表排盐模式，以灌水定额肘和田间排盐梯度TD两因素的不同组合，形成9个试验小区与大田膜下滴灌CK1、常规沟灌CK2、畦灌CK3等3个对照区，在新疆慰犁县西尼尔镇开展大田膜下滴灌试验研究。试验结果表明，在田间水平方向上，1—9试验小区的土壤水盐在0-50cm区域尺度范围由膜中向膜边和膜外运移积累，具有明显的“水盐定向迁移”机制，适宜的灌水定额M=300～375m3／hm^3，排盐梯度TD=10-30cm；而CK1不明显，CK2和CK3不具有定向迁移特征；在田间土壤垂直深度层面上，土壤盐分在40-60cm层深明显多于0-20cm层面，且下层土壤水盐具有向膜边裸露地表提升迁移机制，而CK2和CK3无此水盐运移特征。基于膜下滴灌条件下土壤水盐向田间地表膜边和膜外运移机制和积累效应，采用田间两膜之间的裸露地表排盐沟实施地表排盐，结果表明，试验区地表排盐土壤盐分下降36．7％～63.3％。
To explore the mechanism of directional migration of water and salt in soil and the surface salt-discharging pattern through drip irrigation under plastic film in arid areas, nine experimental treat- ments were set up by various combination of two factors, irrigation quota M and salt gradient TD, compar- ing with three experimental controls, under-plastic drip irrigation CKt, general furrow irrigation CK2 and border irrigation CK3, which were conducted for an under-plastic drip irrigation research project in Xinier town of Weili county in Xinjiang. The results indicate that in the regional-scale of 0-50cm, water and salt in soil of #1-#9 treatments in the horizontal direction migrated and accumulated from center to outside, ＂water and salt directional migration mechanism＂ is obviously identified, suitable at M=300-375m3/hm2, TD= 10-30cm, while in CKI it is not so evident, and CK2 and CK3 do not have directional migration character- istics. In the vertical direction, soil salinity in 40-60cm is more than those in O-20cm layer, water and salt in soil from upgrade layer tend to migrate upward to the film side of bare surface, and in CK2 and CK3, there are no such characteristics. Based on the migration mechanism and accumulation effect of water and salt in soil migrate to the film side and outside in field surface through drip irrigation under plastic film, it took bare surface between two plastic films to start surface salt-discharging. The results show that soil salinity in surface salt-discharging area fell by 36.7%-63.3%.
出处
《水利学报》
EI
CSCD
北大核心
2013年第11期1380-1388,共9页
Journal of Hydraulic Engineering
基金
国家自然科学基金资助项目(51079162)
关键词
干旱区
膜下滴灌
土壤水盐定向迁移
地表排盐
效应
Drip irrigation under plastic film
arid areas
directional migration of water and salt in soil
salt discharging in surface
effect
