摘要：Molecular composition of dissolved organic matter (DOM) and its influencing factors in river reservoirs remains elusive. Here, molecular compositions of DOM, bacterial community structures, and water physiochemistry were investigated in the field and microcosm samples of the Three Gorges Reservoir (TGR). The results showed that DOM molecular compositions were significantly (R2 = 0.245, p < 0.001) correlated with bacterial community structures in the studied field samples, suggesting that bacteria may actively interact with DOM molecules. The molecular compositions of DOM in the studied field samples were significantly (p < 0.05) affected by the distance between the sample sites and the Three Gorges Dam and by bacterial groups of Actinobacteria and Alphaproteobacteria, suggesting that both hydrological and bacterial processes may contribute to the variation in DOM molecular composition in the TGR water. Furthermore, microcosm experiments demonstrated that both microbial and abiotic processes may transform and/or produce DOM in the TGR, thereby affecting DOM molecular composition. Microbial process increased the average aromaticity index and decreased the carbon number of DOM molecules with increasing incubation duration; whereas average oxygen number, double bond equivalent, and oxidation state of carbon of DOM molecules increased during the first 14 days of incubation and began to decrease thereafter. Taken together, this study expands our understanding of the impact of microbial process on the DOM molecular composition in reservoir ecosystems, and has great implications for carbon cycling in major rivers. ? 2023

ISSN号：0009-2541

卷、期、页：卷639

发表日期：2023-11-20

影响因子：0.000000

期刊分区（SCI为中科院分区）：二区

收录情况：EI（工程索引）,地学领域高质量科技期刊分级目录（国外T1）

发表期刊名称：Chemical Geology

参与作者：Yang, Jian,Huang, Liuqin,She, Weiyu,Wu, Geng,Dong, Hailiang,Chu, Rosalie K.,Tolic, Nikola,Jiang, Hongchen

第一作者：万云洋

论文类型：期刊论文

论文概要：Yang, Jian,Huang, Liuqin,She, Weiyu,Wu, Geng,万云洋,Dong, Hailiang,Chu, Rosalie K.,Tolic, Nikola,Jiang, Hongchen，Compositional changes of dissolved organic molecules along water flow and their influencing factors in the Three Gorges Reservoir，Chemical Geology，2023，卷639

论文题目：Compositional changes of dissolved organic molecules along water flow and their influencing factors in the Three Gorges Reservoir