Molecular composition and spatial distribution of dissolved organic matter (DOM) in the Pearl River Estuary, China

He，Chen1; Pan，Qiong1; Li，Penghui2; Xie，Wei3; He，Ding4; Zhang，Chuanlun1,2; Shi，Quan1,2

2019

10.1071/EN19051

Environmental Chemistry   影响因子和分区

1448-2517

1449-8979

The Pearl River is the second-largest river in China in terms of water discharge and brings enormous amounts of nutrients and terrestrial organic matter to the South China Sea, which makes the Pearl River Estuary (PRE) highly eutrophic. However, the molecular composition and distribution of dissolved organic matter (DOM) in the PRE have scarcely been investigated. In this study, solid-phase extraction (SPE) was performed to collect DOM samples from PRE along a salinity gradient. The samples were characterised by negative-ion electrospray ionisation (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to analyse their molecular composition and spatial distribution. The FT-ICR MS results showed that the terrestrial organic matter was gradually diluted and/or degraded during the migration from the river to the coastal ocean. Furthermore, both sulfur containing and unsaturated molecules were highly abundant in the upper stream samples, which indicated that anthropogenic input might be another important source of the assigned DOM in PRE. A group of bio-refractory molecules, characterised as carboxylic-rich alicyclic-like molecules, was found to accumulate with the increase of salinity. The composition of the SPE-DOM showed a gradual variation with the salinity and spatial changes; however, the variation was slightly different from those in pristine estuaries. This study demonstrates that the molecular composition of DOM is crucial for elucidating its source and transformation in an estuary.

FT-ICR MS SPE-DOM

SCI

英语

通讯

National Key Research and Development Program of China[2018YFA0605800][2016YFA0601101] ; National Natural Science Foundation of China (NSFC)[41530105][91851210][91428308][41773098] ; Key Project of Natural Science Foundation of Guangdong Province[2018B030311016] ; Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technology[ZDSYS20180208184349083]

Chemistry ; Environmental Sciences & Ecology

Chemistry, Analytical ; Environmental Sciences

WOS:000532319400002

CSIRO PUBLISHING

2-s2.0-85074213960

Scopus

1.State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum,Beijing,102249,China
2.Shenzhen Key Laboratory of Marine Archaea Geo Omics ResearchDepartment of Ocean Science and EngineeringSouthern University of Science and Technology,Shenzhen,518055,China
3.School of Marine SciencesSun Yat-sen University,Zhuhai,519082,China
4.Institute of Environmental and Biogeochemistry (EBig)School of Earth SciencesZhejiang University,Hangzhou,310027,China

He，Chen,Pan，Qiong,Li，Penghui,et al. Molecular composition and spatial distribution of dissolved organic matter (DOM) in the Pearl River Estuary, China[J]. Environmental Chemistry,2019,17(3):240-251.

He，Chen.,Pan，Qiong.,Li，Penghui.,Xie，Wei.,He，Ding.,...&Shi，Quan.(2019).Molecular composition and spatial distribution of dissolved organic matter (DOM) in the Pearl River Estuary, China.Environmental Chemistry,17(3),240-251.

He，Chen,et al."Molecular composition and spatial distribution of dissolved organic matter (DOM) in the Pearl River Estuary, China".Environmental Chemistry 17.3(2019):240-251.