湧水を伴う湖沼の水平対流と水質特性

抄録

Lake Ezu with rich spring water, which is located in the southeastern, part of Kumamoto city, has been damaged by both urban development and groundwater contamination due to nitrogenous fertilizer for agricultural products in recent years, so that the native plants disappear and naturalized ones propagate. In this study, field observations were carried out in order to investigate the relationships between the currents and water qualities such as DO, SS, BOD and the water temperature in lake Ezu in November of 1997 and August of 1998. From the three-dimensional flow velocities by ADCP and water temperature data, it is recognized that density currents in the bottom layer of the lake took place and these currents determined water qualities in the daytime of the summer.