地下水环境氯离子时空变异性模拟研究

Evaluation of the Spatial and Temporal Variability of Environmental Chloride Ion in Groundwater by Simulation

地下水所在的多孔介质空隙几何条件复杂多变,水文地质参数往往呈空间随机分布,致使地下水水流系统中参数具有时间和空间上的变异性和不确定性。本文着重阐述浅层地下水环境评价中的时空变异性,通过实验模拟浅层地下水非均质运移环境,利用时空地质统计学计算了区域化变量氯离子的时空变异函数,构建了乘积—和时空理论模型,并对时空估计插值方法的应用作了进一步探讨。结果表明,从时间和空间上的变程可以得出浅层地下水水质指标的演变在3.9 h左右,空间上为0.5 m左右;时间边界上的变异性相对空间边界上的要好一些;时空变异性能更精确地反映和估计环境变量在时间和空间的分布,对浅层地下水污染物的迁移运转及预测研究具有重要的现实意义。

The complexity of the variability and uncertainty of groundwater porous media where the gap geometry conditions lead to that the hydrogeological parameters have random distribution in space and the parameters in groundwater flow system have the time and spatial variability and uncertainty. To study the spatial and temporal variability, this article focused on the function of spatial and temporal variability of groundwater in the environmental assessment, simulated the groundwater heterogeneous transport environment of chloride ion through the experiment, by using the space-time geostatistics, the spatial and temporal variability of the regionalized variable chloride ion is calculated, to build a product --sum space-time theory model, and further to explore the application of space and time estimation interpolation method. The results show that the evolution of water quality indicators can be drawn from the change process in time and space at about 3.9 hours and 0.5m ; also, the time marginal variability can be used to characterize the water quality objectives evolution better than the relative space one; the temporal and spatial variation can refleet the distribution of the environment variables in time and space more accurately. It has an important practical significance to the research of migration operation and prediction of the groundwater pollution.