乞盖淖湖湖床垂向渗透系数试验研究

In-situ Vertical Hydraulic Conductivity Test for Qigainao Lake

地下水与湖水的转化必须要通过湖床沉积物，因此湖床渗透系数是评价湖水与地下水定量转化关系的基础。以内蒙古伊金霍洛旗乞盖淖湖为例，首先分析了湖床沉积物的颗粒组成，然后利用现场渗透试验方法进行了野外试验，计算了湖床的垂向渗透系数。湖床沉积物粒径分析结果表明，湖床沉积物以粉细沙为主。湖床垂向渗透系数计算结果表明，各测点的平均垂向渗透系数介于0．83～13．59cm／d，表明乞盖淖湖床垂向渗透性能在空间上具有非均质性。该研究为定量计算地下水与湖水的转化关系提供了基础参数。

Exchange between ground water and lake water must be through lakebed, thus lakebed hydraulic conductivity is the basis for quantitative assessment of lake water and ground water transformation. The paper presents hydraulic conductivities of lakebed measured in Qigainao lake in Yijinhuoluo, Inner Mogolia. Grain size distribution was determined, then in situ permeation tests were conducted to evaluate the vertical hydraulic conductivities （Kv）. Grain size analysis shows that lakebed consists mainly of fine sand. Results show that Kv of the lakebed is heterogonous in space. The average Kv values vary from0. 83 to 13.59 cm · d-1 which provides basic parameter to qualify exchange rates between ground water and lake ater.