半干旱地区包气带—饱和带水盐耦合模拟

Water-salt Coupled Simulation in Vadose Zone and Saturated Zone in Semiarid Area

通过GMS和Hydrus的结合,构建包气带—饱和带的水盐耦合模拟模型,以半干旱地区宁夏中卫某速生林高阶地为例,采用历史数据进行了验证,验证结果表明,该模型可有效模拟包气带—饱和带的水流运动和氯离子的运移情况。利用该模型对研究区的水盐变化情况进行分析,结果表明,研究区地下水流向为西北—东南方向,氯离子呈现放射状扩散趋势且与水流方向一致,受造纸废水灌溉的影响,地下水氯离子浓度逐年上升,且浓度累积速率不断提高。

A coupled simulation model of water and salt transportation in vadose zone and saturated zone was developed with GMS and Hydrus in this paper. Data measured in a fast-growing woods in high level terraces in Zhongwei in a semiarid area in Ningxia were used to demonstrate the reliability of the model. The simulated results showed that the model was effective. Based on the coupled simulation model,groundwater and salt transportation processes in the study area were analyzed. The results revealed that the groundwater flow flowed from the northwest to the southeast. Moreover,chlorine ion in groundwater was in a diffusion trend and had the same direction with groundwater flow. Influenced by irrigation with papermaking wastewater,the chloride ion concentration in groundwater was increased year by year,and the chlorine ion accumulation rate was increased continually.