太湖地区典型小流域地下水储量动态模拟与分析

对太湖地区典型小流域的近地表地质特征进行系统野外试验,分析近地表土层土壤和岩层结构特征,初步确定了含水层计算参数;采用三维地下水流数值模拟方法概化水文地质条件,识别与验证模型参数。结果表明:地表水补给地下水的量约是地下水补给地表水总量的2倍,山溪型小流域的地表地下水交互过程趋于单向交换,即河道水补给地下水。从含水层储水量变化看,除去蒸散发,通过地下通道流失的水量占据总水量的相当比重,且地下储水的减少量主要依赖降雨入渗进行补给。所建立的模型能够较好地反映研究区实际的水文地质条件,揭示地表水和地下水的交互量的变化过程,并定量研究流域水量平衡动态关系,可为变化环境下的地下水保护和滨湖区的地下水潜流计算研究提供预测分析依据。

Dynamic simulation and analysis of groundwater storage in typical watershed of Taihu Basin

This study was carried out in a typical small watershed of the Taihu Basin. The aquifer calculation parameters were identified through systematic field experiments on near-surface geological features and analysis of near-surface soil and rock structural features. The three-dimensional groundwater numerical simulation method was used to generalize the hydrogeological conditions, and to identify and verify the model parameters. The results show that the surface water recharge to groundwater is approximately twice the groundwater recharge to the surface water, and the interaction between the surface water and groundwater in stream-type watersheds tends to be unidirectional. That is, the river water recharges groundwater. In terms of the change of water storage in the aquifer, in addition to evapotranspiration, water loss through the underground passage accounts for a large proportion of the total water amount, and the reduced groundwater storage is recharged mainly by rainfall infiltration. The established model can well reflect the actual hydrogeological conditions of the study area. It has been used to describe the change process of the interaction between the surface water and groundwater, and to quantitatively study the dynamic changes of the basin water balance. In addition, it can provide a basis for the prediction and analysis of groundwater protection in changing environments and groundwater undercurrent calculation of lake areas.