毛乌素湖盆滩地湖水与地下水交互作用分析

湖水与地下水交互作用对于水资源合理开发与利用有着重要意义。基于温度示踪的原理,采用解析法、数值法2种方法,分析了湖床底部埋深0~0.4 m湖水与浅层地下水交互关系,并与水动力学方法进行了对比。结果表明,2018年5月20日至28日,湖水与地下水之间的垂向渗流速度为2×10^-7~1×10^-6 m/s,且在埋深0.4 m时大于埋深0.2 m处。降水会对解析法的结果造成一定影响,0.4 m处受到降雨影响表现为一定的滞后性。无降雨干扰情况下,数值法与水动力学方法估算结果较为吻合,且3种方法的计算结果处于同一数量级。同时,湖床沉积物体积热容和孔隙度2种参数对计算结果影响较大。在半干旱地区湖水与地下水交互研究中,数据较完备时,数值模拟法是更好的选择。

Analysis of interaction between lake water and groundwater in beach of Maowusu Lake Basin

The interaction between lake water and groundwater is of great significance to the rational development and utilization of water resources. In this paper, based on temperature tracer principle, two methods including of the analytical method and numerical simulation method are used to comprehensively study the interaction between lake water and groundwater with a buried depth of 0-0.4 meters at the lake bed in the beach of Maowusu Lake Basin. In addition, compared with the result by hydrodynamic method. The results show that from May 20 to 28, 2018, the vertical seepage velocity between lake water and groundwater is 2×10-7-1×10-6 m/s, and the seepage velocity at the buried depth is 0.4 m is greater than that at the buried depth of 0.2 m. Precipitation have a certain impact on the results of analytic method, and there is a certain lag in the seepage velocity at the buried depth of 0.4 m. Without less rainfall interference, the results of numerical method and hydrodynamic method are of good agreement, furthermore the results of the three methods are in the same order of magnitude. At the same time, the volume heat capacity and porosity of lake bed sediments have great influence on the results. In the study of interaction between lake water and groundwater in semi-arid areas, numerical simulation is much better choice when the monitoring data are collected completely.