| Title |
Analysis of Water Quality Variation after Hydraulic Changes in Yeongsan River |
| Authors |
김유흔 ( Yu-Heun Kim ) ; 이혜원 ( Hye-won Lee ) ; 최정현 ( Jung-Hyun Choi ) |
| DOI |
https://doi.org/10.15681/KSWE.2022.38.1.1 |
| Keywords |
Non-parametric test; Spatiotemporal plot; Water quality; Weir; Yeongsan River |
| Abstract |
The Yeongsan River, one of the four major rivers in Korea, shows the highest degree of water pollution compared to the other major rivers. The construction and opening of two weirs, Seungchon and Juksan, induced fluctuations in the hydrologic conditions and water quality of the river. To investigate the water quality changes caused by the opening of the weir in 2017, this study analyzed the water quality data using the non-parametric Wilcoxon signed-rank test and the three-dimensional spatiotemporal plots. The non-parametric statistical test results showed that the concentration of all parameters has increased after 2017 at a significance level of 0.05. For the parameters that showed the highest degree of change, chlorophyll-a and suspended solids, the median values have increased by more than 30% after weir opening. Visual analysis additionally showed the spatial changes in the Yeongsan River. Generally, the sites above the Seungchon weir showed higher pollution levels than those above the Juksan weir. In time series, visual analysis results also showed the trend of rising concentration for all water quality parameters, indicating that the opening of two weirs had a significant effect on the change in water quality of the Yeongsan River. |