5:15 PM - 6:45 PM
[AHW18-P01] Identification of sources and evaluation of their influence using spatiotemporal variation of dissolved trace elements in the upper Nakdong River, South Korea
Keywords:Trace elements, Statistical analysis, Water source, Water quality
The water chemisry of surface water is highly dependent on the hydrological and hydrogeochemical conditions of drainage basin. The increase in anthropogenic activities and the presence of multiple emission sources can cause spatiotemporal variations in the concentration of dissolved trace elements (DTEs) in surface water system. In the upper Nakdong River (UNR), various sources associated with mining activities are present, potentially causing adverse effects on the river. The goal of this study was to identify he representative sources of DTEs that affect the surface water quality of the UNR and to determine the hydrological processes associated with inflow anthropogenic sources into UNR. For this study, multivariate statistical analysis such as Kruskal-Wallis (KW) test, hierarchical cluster analysis (HCA), and principal component analysis (PCA) were performed to identify the anthropogenic sources and their contribution affecting water quality of UNR. In addition, hydrological processes that control spatiotemporal variabilities of DTEs were determined by the correlation between principal components (PCs) and d-excess. The highlight of this study is the identification of three pollution sources (acid mine drainage, leachate from mine tailings, and smelters) influencing river water quality through PCA. Furthermore, the combination of TW and HCA were useful in quantifying the spatial and temporal contribution changes of these three sources. In particular, the comparison between d-excess and PCs indicated that the inflow of harmful DTEs from smelters into UNR may depend on baseflow of contaminated groundwater in the smelters associated with hydrological regime rather than surface runoff.