Long-term effects of wildfires on river water quality: a comprehensive review of the variability of water quality in South Korea.

After wildfires, the loss of the humus layer leads to increased runoff and pollutants entering rivers. This study examined the long-term effects of wildfires on water quality. We statistically analyzed the changes in the water quality of streams surrounding the wildfire area. We used eight water quality parameters provided by the National Institute of Environmental Research for the analysis. To assess the impact of the wildfires, we employed t-tests and point-biserial correlation analysis to compare the changes in water quality indicators before and after the wildfires. Additionally, an analysis of variance was conducted to evaluate the impact of three wildfires, each occurring in different periods, on the water quality in a single river basin. The results showed increasing trends in hydrogen ion concentration (pH), electrical conductivity, and dissolved oxygen after the wildfire, whereas biochemical oxygen demand, total phosphorus, and total nitrogen exhibited decreasing trends. The impact of wildfires on changes in suspended solids was relatively minimal. It is expected that the results of this study provide valuable insights into developing water quality management and restoration plans following wildfires.