微咸水水质对土壤水盐运移特征的影响  

Effects of Slight Saltwater Quality on the Characteristics of Soil Water and Salt Transference

作　　者：史晓楠[1] 王全九[1,2] 苏莹[1] 

机构地区：[1]西安理工大学,陕西西安710048 [2]土壤侵蚀与旱地农业国家重点实验室

出　　处：《干旱区地理》2005年第4期516-520,共5页Arid Land Geography

基　　金：国家"863"计划项目(2002AA224061)国家自然基金项目(40371057)资助

摘　　要：微咸水的合理开发和利用不仅有利于缓解水资源供需矛盾,而且有利于生态环境保护和农业可持续发展。通过以微咸水矿化度和钠吸附比(SAR)为两个主要指标,在实验室就8种微咸水水质对土壤入渗特征及水盐动态的影响进行了研究。研究结果表明微咸水矿化度的增加通过改善土壤的团粒结构从而增加了土壤的透水性;而相对土壤钠吸附比较高的情况下,低矿化度低钠吸附比入渗水的钠吸附比对土壤入渗特征影响不明显。土壤的含盐量主要取决于入渗水的矿化度,受钠吸附比的影响不大,矿化度小于或等于3g/L时,表层土壤中的盐分处于平衡状态。土壤溶液的钠吸附比与入渗水的矿化度和钠吸附比均呈良好的线性相关关系,入渗水矿化度越大,钠吸附比越大,土壤饱和溶液的钠吸附比越大。Precipitation is less in the arid and semiarid regions in north and northwest China, and the shortage of water resources has become as a restrictive factor for the sustainable development of agriculture. These regions, however, are rich in saltwater and slight saltwater resources, and secondary soil salinization occurs easily. Therefore, rational exploitation and utilization of slight saltwater can not only alleviate the contradiction between the supply and demand of water resources, but also is advantageous for the conservation of ecological environment and the sustainable development of agriculture. By taking the salt content and sodium absorption ratio of slight saltwater as the main indexes, in this paper the effects of slight saltwater with 8 different water qualities on soil infiltration properties and water-salt transference are researched. The experimental results show that the increase of salt content of slight saltwater can improve soil porosity by changing soil aggregate structure and increasing soil conductivity. Since soil SAR is higher than infiltration water, the effect of the SAR change of infiltration water with low salt content on soil infiltration properties is not so obvious. Soil salt content greatly lies on water salt content and has little relation with SAR of water. When salt content of water less than or equal to 3g/L, the distribution of salt in topsoil is balanceable. The SAR of soil solution has a good linear correlation with salt content and SAR of infiltration water. The higher the salt content and SAR of water is, the greater the SAR of soil saturated.

关 键 词：微咸水 矿化度 钠吸附比(SAR) 土壤水盐 

分 类 号：S152.7[农业科学—土壤学]