분포형 물수지 모델(WetSpass-M)을 이용한 삽교천 상류 유역에서의월별 지하수 함양량 산정

In this study, the annual and monthly groundwater recharge for the Sapgyo-cheon upstream basin in Chungnam Provincewas evaluated by water balance analysis utilizing WetSpass-M model. The modeling input data such as topography,climate parameters, LAI (Leaf Area Index), land use, and soil characteristics were established using ArcGIS, QGIS, andPython programs. The results showed that the annual average groundwater recharge in 2001 - 2020 was 251 mm, whilethe monthly groundwater recharge significantly varied over time, fluctuating between 1 and 47 mm. The variation washigh in summer, and relatively low in winter. Variation in groundwater recharge was the largest in July in whichprecipitation was heavily concentrated, and the variation was closely associated with several factors including the totalamount of precipitation, the number of days of the precipitation, and the daily average precipitation. This suggests theextent of groundwater recharge is greatly influenced not only by quantity of precipitation but also the precipitation pattern. Since climate condition has a profound effect on the monthly groundwater recharge, evaluation of monthly groundwaterrecharge need to be carried out by considering both seasonal and regional variability for better groundwater usage andmanagement. In addition, the mathematical tools for groundwater recharge analysis need to be improved for more accurateprediction of groundwater recharge.