Analysis of Water-Salt Dynamics of Saline-sodic Soil in the Condition of Different Groundwater Tables

Soil salinization is one of main ecological environmental problems in Songnen Plain.Groundwater depth and mineralization have an important influence to the salinization happening and the water-salt transport of saline-sodic soil.This research studied the water-Salt dynamics in the condition of different groundwater tables through field experimentation in Da'an Sodic Land Experiment Station of China,and the law of water-salt movement was discussed.Through the analysis of soil water content and salinity,it was found that the degree of soil salinization was more seriousduring experiment.The shallower groundwater tables,the smaller the changes of soil volumetric water content in soil profile.Because of precipitation and evaporation,the variety extentof soil water content above 80cm depth is great,and the variety extentof soil water content above 40cm depth was obvious during experiment(from June to October).Soil salinity and main ion content(Na+、HCO3) is biggest at the depth of 60cm or 100cm,and in the action of precipitation and evaporation,soil salinity and main ion content trend of high-low-high during experiment(from June to September).