Characteristics of Hydrochemistry and Stable Isotopes in a Karst Region in Samcheok, Republic of Korea

Abstract

Karst regions cover approximately 10% of the Korean Peninsula and are highly vulnerable to contamination. In this study, five field surveys were conducted between 2017 and 2019 to examine the monthly and seasonal changes in the hydro-environment of a characteristic karst region in Samchoek, South Korea. During the surveys, a total of 24 surface water samples were collected and analyzed for field water quality parameters, major and minor ions, and stable isotopes. The results indicate that the water quality in the study area is significantly affected by precipitation. Overall, the water was classified as a Ca-Mg-HCO3 type, and correlation analysis of the major ions detected in the water samples indicates that the inflow of nitrate to the surface water originated from agricultural activities in the region. Furthermore, variations caused by climate were verified using the relationships between the various ions. In addition, high precipitation rates during the rainy season cause the active exchange of surface material, which was verified using stable isotope outliers. The results provide a scientific basis for studying the connectivity of water systems in complex karst hydrogeological regions and can aid future sustainable management of water resources in these regions.

Characteristics and Connectivity Analysis of Hidden Karst in Jurong Pumped Storage Power Station Area, China

“…By combining natural tracer tests and an artificial tracer test with salt, the leakage zone of the dam wall can be identified. Isotope tracer test and hydrochemistry monitoring can be used to analyze the recharge and discharge conditions and connectivity of groundwater systems in a karst aquifer [20][21][22][23]. Hydrochemical analysis and tracer tests were used to identify the groundwater-leakage mechanism and passage of dams [24][25][26].…”