松嫩平原盐沼湿地冻融期水盐动态研究——吉林省长岭县十三泡地区湖滩地为例

Research on the Water and Salt Dynamics in Salinized Wetlands of Songnen Plain During the Freezing/Thawing Period ——Taking the lakebeach in Shisan lake, Changling District as an example

以吉林省长岭县十三泡地区湖滩地为例 ,选取有代表性的月份进行定位观测、实验和对比分析 ,研究了冻融期盐沼湿地水盐运移的特殊规律性。研究表明 ,盐沼湿地冻结期 ,由于冻层的存在 ,土体内产生的温度梯度、水势梯度 ,是冬季水盐积累的驱动力。在冻结期 ,冻层水盐自底层向上迁移 ;融冻期 ,冻层自地表向下及自暖土层向上双向融化 ,在冻层形成上层滞水 ,在冻层之下水盐从下向冻层迁移冻结。冻融期间盐沼湿地水盐迁移的热力学机制是松嫩平原土壤盐化发生机制的重要组成部分。

It was carried out in the observation of orientation, the analyze of experimentation and comparison in (Apr., July, Sept., Dec.) of 2004 selected. This article researches the water and salt transportaton dynamics of the salinized wetlands in Songnen Plain during freezing and thawing period. It shows that temperature gradient and soil water potential gradient presented in the soil are the drive factor of salt accumulation in the winter because of the presentation of frozen layer. During the freezing period, the water salt of frozen layer transports from bottom to top; during the thawing period, frozen layer thaws in two directions: from the soil surface to deep layer and from the unfrozen layer up to top layer frozen, and the upper stagnant water was formed above the frozen layer, meanwhile, below the frozen layer, water and salt transports and freezes from the unfrozen layer up to frozen layer. The thermo dynamics mechanism of water and salt transportation in the salined wetland during the freezing and thawing period is substantial to the geographical occurrence mechanism of salinized soil.