盐渍土的热力构型对水盐运移的影响研究  

The Influence of Thermal Dynamic Structure of Saline Soil on Water and Salinity Transportation

作　　者：罗金明[1] 许林书[2] 邓伟[3] 张晓平[1] 杨帆[1] 李秀军[1] 

机构地区：[1]中科院东北地理与农业生态研究所 [2]东北师范大学城市与环境科学学院,长春130024 [3]中科院成都山地灾害研究所,成都6100413

出　　处：《干旱区资源与环境》2008年第9期118-123,共6页Journal of Arid Land Resources and Environment

基　　金：中科院知识创新重大项目(KZCX1-SW-19-02)资助

摘　　要：通过野外定位观测和室内分析,探讨了冻融季节苏打盐渍土的热力构型及对苏打盐渍土的水盐变化的影响。结果表明:土体热力梯度是水盐运移的诱导因素和驱动力。冬季松嫩平原西部土体热力构型为冷冻层-过渡层-暖土层;消融季节土体热力构型为暖土层-过渡层-冷冻层-过渡层-暖土层。受土体热力梯度和水势梯度驱动,潜水向冻结层积聚形成冻土。土壤类型不同,冻土的组成和性质存在显著差异。盐化草甸土和苏打草甸盐土成为水分迁移的汇集区,大量地下水汇集在盐化草甸土和盐土的冻层中,0-70 cm土层的含水率显著增加,最高含量达60%。苏打草甸盐土和白盖苏打碱土的冻层为盐分汇集区,苏打盐土和白盖苏打碱土0-70 cm土层土壤盐分增加明显,其中0-40 cm土层的盐分增量最显著。冻土层积聚大量盐分导致消融季节土壤的盐渍化程度不断加重。By in -situ observation and analysis in laboratory, the thermal dynamic structure of sodic saline soil and its influence on the water and salinity transportation were discussed. Results showed that the soil dynamic gradient was the key inducing factor and motivity for water and salinity transportation. The dynamic structure in frozen season appeared to be cold frozen layer -frozen fringe -warm layer, and warm layer- frozen fringe -cold frozen layer -frozen fringe -warm layer in thawing period. Impulse by thermal dynamic gradient and moisture potential gradient, shallow groundwater accumulated in frozen layer. Due to the difference of soil type, the component and properties of frozen soil body were different obviously. Saline meadow soil and saline soil became the accumulation sink of shallow ground water, where vast groundwater transported and stored, and the moisture in 0 - 70 cm layer increased significantly （ maximal water content reached 60% ）. White crust sodic alkaline soil and sodic meadow saline soil became the accumulation sink of salinity. And salinity content in 0 -40 cm layer enriched most significantly. The vast salinity accumulation in surface layer resulted in the saline degree gradually aggravated in thawing season.

关 键 词：温度梯度 冻融作用 水盐迁移 

分 类 号：S156.4[农业科学—土壤学]