Characterizing the transitory groundwater-surface water interaction and its environmental consequence of a riverside karst pool

Exchange between groundwater (GW) and surface water (SW) is a common occurrence in karst water systems through sinking stream disappearance or groundwater emergence. However, the transitory GW-SW interaction caused by river backflowing into a spring is poorly observed and understood. In this study, we present an approach for characterizing the influence of GW-SW interaction in a karst spring by integrating high-resolution hydrology, carefully selected hydrochemistry monitoring and precise microbe measurements. The spring-fed pool water conditions can be distinguished as high, medium, and low-water level periods in a hydrological year. The high-water level accounts for