[Research Progress on Component Characteristics and Influencing Factors of Dissolved Organic Matter in Water Bodies of the Yangtze River Basin].

Dissolved organic matter （DOM） is a complex mixture that includes humus, proteins, and other water-soluble organic compounds. Its characteristics have a notable impact on the environmental behavior of various pollutants in the water environment within a basin. The characteristics of DOM components were conducted in both the mainstream and tributaries, with a discussion of the factors that influence DOM in the Yangtze River Basin. Finally, the future challenges to be addressed were identified. The compositional characteristics of DOM in the waters of the Yangtze River Basin showed significant spatiotemporal heterogeneity, which was mainly manifested by significant differences in DOM concentration, aromaticity, degree of humification, composition, molecular diversity, and source of the main tributaries, lakes, and reservoirs （horizontal and vertical） of the Yangtze River in different geographical locations and seasons. These differences were mainly influenced by climate and hydrology, human activities, and land use patterns along the river basin. Currently, research into the characteristics of DOM components in the Yangtze River Basin is still in its preliminary stages, with a particular focus on surface water bodies. In recent years, the development and application of Fourier-transform ion cyclotron resonance mass spectrometry and other technical means have enabled high-resolution analysis of DOM at the molecular level. It is recommended that a study be conducted immediately on the evolution of DOM component characteristics in the Yangtze River Basin over a long time series, large scale, and multiple media, to further reveal the influence, including changes in DOM component characteristics on the environmental geochemistry of pollutants and their ecological effects on a basin scale.