Optical and molecular signatures of dissolved organic matter in Xiangxi Bay and mainstream of Three Gorges Reservoir, China: Spatial variations and environmental implications

Wang, Kai1; Pang, Yu1; He, Chen2; Li, Penghui3; Xiao, Shangbin4; Sun, Yongge1; Pan, Qiong2; Zhang, Yahe2; Shi, Quan2; He, Ding1

2019-03-20

10.1016/j.scitotenv.2018.12.117

SCIENCE OF THE TOTAL ENVIRONMENT   影响因子和分区

0048-9697

1879-1026

With the on-going boom in the construction of dam reservoirs all over the world, the sources and composition of dissolved organic matter (DOM) in fluvial networks are expected to be altered. Considering the importance of DOM as a key biogeochemical component in inland waters, this might bring important ecological and environmental influences. However, limited information is available on the molecular composition of DOM in dam reservoirs. In this study, the spatial characteristics of DOM composition were investigated in Xiangxi tributary and mainstream of the Three Gorges Reservoir (TGR), the largest freshwater reservoir in the world. The concentration alteration of conservative cations revealed the water intrusion from mainstream into Xiangxi tributary, which mainly controlled the hydrological gradient. One tyrosine-like (C4), one tryptophan-like (C2), and two humic-like (C1 and C3) fluorescent components were identified in fluorescent DOM (FDOM) by parallel factor analysis (PAFACAC), potentially indicating algal, anthropogenic, and terrestrial inputs, respectively. Decreasing trends of C1, C3 and C4 components and an increasing trend of C2 component were observed from Xiangxi tributary to mainstream, indicating higher terrestrial and algal inputs but lower anthropogenic inputs in Xiangxi tributary compared to mainstream. The Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) characterization further revealed substantial heterogeneity of DOM at the molecular level. Interestingly, S-containing compounds related to synthetic surfactants were consistently detected, and their relative abundances showed an increasing trend from Xiangxi tributary to mainstream, in agreement with the distribution of the anthropogenic derived C2 component. Meanwhile, numerous lignin-like S-containing compounds were identified, likely the result of the incorporation of sulfide ions to lignin-like CHO compounds. This study represents the first molecular level characterization of DOM in the TGR system, which should aid the design and implementation of more detailed future studies. (C) 2018 Elsevier B.V. All rights reserved.

Dissolved organic matter Three Gorges Reservoir Fourier transform ion cyclotron resonance mass spectrometry Optical properties Molecular composition Spatial variations

SCI ; EI

英语

其他

Zhejiang University[188020*194231701/008] ; Zhejiang University[188020-193810201/102]

Environmental Sciences & Ecology

Environmental Sciences

WOS:000455903400124

ELSEVIER SCIENCE BV

20185106259480

Amino acids ; Biogeochemistry ; Cyclotrons ; Dissolution ; Electron cyclotron resonance ; Fluorescence ; Ions ; Lignin ; Mass spectrometry ; Optical properties ; Organic compounds ; Sulfur compounds

Reservoirs:441.2 ; Light/Optics:741.1 ; Chemistry:801 ; Biochemistry:801.2 ; Chemical Operations:802.3 ; Organic Compounds:804.1 ; Cellulose, Lignin and Derivatives:811.3 ; Atomic and Molecular Physics:931.3 ; Particle Accelerators:932.1.1

ENVIRONMENT/ECOLOGY

Web of Science

1.Zhejiang Univ, Inst Environm & Biogeochem eBig, Sch Earth Sci, Hangzhou 310027, Zhejiang, Peoples R China
2.China Univ Petr, State Key Lab Heavy Oil Proc, Beijing 102249, Peoples R China
3.Southern Univ Sci & Technol, Dept Ocean Sci & Engn, Shenzhen 518055, Peoples R China
4.China Three Gorges Univ, Coll Hydraul & Environm Engn, Yichang 443002, Peoples R China

Wang, Kai,Pang, Yu,He, Chen,et al. Optical and molecular signatures of dissolved organic matter in Xiangxi Bay and mainstream of Three Gorges Reservoir, China: Spatial variations and environmental implications[J]. SCIENCE OF THE TOTAL ENVIRONMENT,2019,657:1274-1284.

Wang, Kai.,Pang, Yu.,He, Chen.,Li, Penghui.,Xiao, Shangbin.,...&He, Ding.(2019).Optical and molecular signatures of dissolved organic matter in Xiangxi Bay and mainstream of Three Gorges Reservoir, China: Spatial variations and environmental implications.SCIENCE OF THE TOTAL ENVIRONMENT,657,1274-1284.

Wang, Kai,et al."Optical and molecular signatures of dissolved organic matter in Xiangxi Bay and mainstream of Three Gorges Reservoir, China: Spatial variations and environmental implications".SCIENCE OF THE TOTAL ENVIRONMENT 657(2019):1274-1284.