2023 Volume 79 Issue 25 Article ID: 23-25023
Dissolved organic matter (DOM) transported from terrestrial sources to coastal areas is important for carbon and nutrient cycling as well as trace metal transport. In this study, DOM composition in the Tama River basin was investigated by ultra-high-resolution mass spectrometry, and the mechanisms of DOM formation and transport were discussed. As a result, the molecular composition of CHO was found to be abundant in upstream river water and litter (terrestrial plant) samples. On the other hand, a large proportion of molecular compositions containing heteroatoms (such as N and S) were found in effluent from waste water treatment plant (WWTP), downstream and coastal waters, while common molecular compositions found in all stations accounted for a relatively high proportion (33-58%) in each sampling station. About one-third of the molecular compositions detected in treated wastewater were not detected downstream waters. Many of them contained heteroatoms, suggesting that such compounds may have been decomposed or transformed during the downstream processes.
