暗管排水条件下微咸水灌溉对土壤水盐运移特征的影响

Transport Feature of Soil Water-salt by Saline Water Irrigation under Subsurface Pipe Drainage

为探索高效节水控盐灌排技术,通过田间试验,以玉米为试材,研究了不同微咸水矿化度及暗管埋深对土壤水盐运移的影响。结果表明,微咸水矿化度和暗管埋深对土壤含水率和盐分均有影响,高矿化度处理灌后土壤含水率比低矿化度高,1.3m暗管埋深灌后土壤含水率要高于0.8m暗管埋深;微咸水灌后1d作物主要根系层（0～40cm）脱盐率受矿化度影响较大,矿化度越高,脱盐效果越差;灌后25d,淡水灌溉及暗管埋深0.8m、3g/L微咸水的处理土壤无积盐,其余各处理均发生积盐现象,灌溉水矿化度越大,0～80cm土层积盐越强烈,1.3m暗管埋深较0.8m埋深土壤积盐更加明显。建议同类型区种植玉米时暗管埋深为0.8m,灌溉使用微咸水矿化度不超过3g/L为宜。

To explore an efficient water-saving and salt-controlling technology,impacts of different concentrations of saline water and different burial depths of subsurface pipe on soil water-salt movement were studied.Results showed that both concentration and burial depth had effects on soil water content and salt content.Soil water content increased with the increasing concentration of saline water.Soil water content of 1.3mdepth was larger than 0.8mdepth.24 hours after irrigation with saline water,the concentration of saline water had a significant influence on the desalination rate of main root region（0～40cm）,the higher the concentration,the worse the desalting effect.25 days after irrigation,there was no salification when irrigation with fresh water saline water of 3g/L while the buried depth of the pipe was 0.8m,all of the other treatments were in the case of salt accumulation.The higher the concentration,the more intense the salification of 0～80cm soil layer.The solification of 0.8 mdepth was better than 1.3 mdepth.Burial depth of 0.8mand the concentration which was less than 3g/L were recommended.