In this study, changes in the properties of dissolved organic matter (DOM) released from sediments into water layers were investigated. To analyze the spatial and temporal variation in dissolved organic carbon (DOC), sediment and bottom water samples were collected upstream of the Gangcheon, Yeoju, and Ipo weirs of the Namhan River during the rainy and non-rainy seasons. The initial DOC was correlated with precipitation (R2 = 0.295, p = 0.034) and residence time (R2 = 0.275, p = 0.040). The change in the bottom water DOC concentration resulted from the DOC released from the sediments, which may cause water quality issues in the bottom water. The fluorescence analysis revealed that the DOM contained higher levels of hydrophilic and low-molecular-weight (LMW) organic matter in the non-rainy season and higher levels of hydrophobic and high-molecular-weight (HMW) organic matter in the rainy season. Since the Namhan River is the main resource of drinking water for the Seoul metropolitan area, our results can help to optimize the drinking water treatment process by reflecting the DOM characteristics that vary with the seasons. Furthermore, the statistical analysis confirmed that the nutrient content of pore-water and sediment can be used to estimate the DOM release rate from the sediment to the water layer. The results of this study provide a better understanding of DOM movement in aquatic ecosystems and the influences of rainfall on the water quality of the surface waterbody.
|Journal||International Journal of Environmental Research and Public Health|
|State||Published - 1 May 2022|
Bibliographical noteFunding Information:
Funding: This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2018R1A6A1A08025520 and 2016R1D1A1B04934910). Additionally, this work is financially supported by Korea Ministry of Environment (MOE) Graduate School specialized in Integrated Pollution Prevention and Control Project, the Korea Ministry of Environment (Research on the effects of water quality due to environment of weir sediment) and the National Institute of Environmental Research in Korea.
© 2022 by the authors. Licensee MDPI, Basel, Switzerland.
- dissolved organic matter (DOM)
- optical properties
- release rate
- sediment-water interface