Assessment of Future Climate Change Impact on Groundwater recharge, Baseflow and Sediment in Steep Sloping Watershed

RegionalInfrastructureEngineering,KangwonNationalUniversity,Korea*EnvironmentalResearchCenter,KangwonNationalUniversity,Korea**DepartmentofAgriculturalandBiologicalEngineering,PurdueUniversity***DepartmentofCivilEngineering,Inhauniversity,Korea요 약기후변화로인해폭우및재해들이일어나고있다. 특히강우강도가커짐에따라토사유출도심해지고있다. 이에따라효율적인수자원및수질관리를위해지하수함양량과기저유출, 그리고토사유출현황을평가하는것이필요하다. 이에본연구에서는대표적인급경사지유역인양구해안면유역에미래기후변화시나리오를적용하여지하수함양량, 기저유출량, 유사량을전망하였으며, 또한유역의경사도를완만하게줄임으로서지하수함양량, 기저유출량, 유사량의변화를분석하였다. 모의기간을2013~2040년, 2041~2070년, 2071~2100년으로나누었으며, 급경사지유역보다유역의경사도를완만하게줄인경우가지하수함양량이평균50% 증가되었으며, 기저유출량도약42% 증가되었다. 유사량은급경사지유역보다경사도를완만하게줄였을경우가72% 유사량이줄어드는것으로나타났다. 본연구의결과에서보이는바와같이경사도를완만하게적용하면유역내지하수함양량및기저유출량이증가하고, 유사량을저감시킬수있는것으로분석되어향후탁수에긍정적인영향을미칠것으로판단된다.핵심용어:SWAT, 유사량, 기저유출, 지하수함양량, 기후변화AbstractClimate change has caused detrimental phenomena such as heavy rainfall which could aggravate soil erosion. Accordingly, itis needed to evaluate the groundwater recharge, baseflow, and soil erosion for the efficient management of water resourcesand quality. In this study, future climate change scenarios were applied to the Haean-myeon watershed which is a steepsloping watershed in South Korea to analyze groundwater recharge, baseflow, sediment. Also, the variation of groundwaterrecharge, baseflow, sediment was analyzed according to the change of slope (5 %). Simulated periods were divided intothree terms (2013 ~ 2040 years, 2041 ~ 2070 years, 2071 ~ 2100 years). As a result of this study, average groundwaterrecharge and baseflow increased by 50 %, 42 %, and sediment decreased by 72 %, respectively. In these regards, thesuggested method will positively contribute to hydro-ecosystem and reduction of muddy water at a steep sloping watershed.Keywords:SWAT, Sediment, Baseflow, Groundwater recharge, Climate Change+ Corresponding Author: jung.younghun@gmail.com