투과매질 모델 기반 수치수조를 이용한 연안침수에 따른 해안지하수 염분화 분석

Abstract

Coastal inundation caused by seawater overtopping/overflow due to sea level rise and extreme coastal disaster events poses a significant threat to coastal groundwater resources. Seawater intrusion into coastal aquifers accelerates salinization, disrupting the natural freshwater balance and limiting sustainable water supply for drinking and agriculture. This study uses numerical simulations based on a porous body model to investigate the vertical seawater intrusion process triggered by coastal inundation. The inundation height, distance, and hydraulic gradient effects on salinization and recovery dynamics in coastal aquifers were analyzed. The results indicate that longer inundation distances cause more extensive salinization, whereas higher inundation heights accelerate vertical intrusion. Additionally, lower hydraulic gradients lead to prolonged retention of saline water, delaying recovery. In contrast, higher hydraulic gradients facilitate rapid discharge of intruded seawater, accelerating salinization recovery. The recovery process follows a logarithmic trend, initially rapid but slowing. These findings emphasize the importance of understanding the interplay between coastal inundation conditions and groundwater flow dynamics to effectively manage and protect coastal freshwater resources.