Molecular composition and characteristics of Sediment-adsorbed Dissolved Organic Matter (SDOM) along the coast of China

Zelong Yan; Jitao Lv; Yuanbi Yi; Xu Ma; Guoqing Zhang; Shaofeng Wang; Xiangfeng Zeng; Yongfeng Jia

doi:10.1016/j.scitotenv.2024.172134

Molecular composition and characteristics of Sediment-adsorbed Dissolved Organic Matter (SDOM) along the coast of China

Sci Total Environ. 2024 Jun 10:928:172134. doi: 10.1016/j.scitotenv.2024.172134. Epub 2024 Apr 5.

Authors

Zelong Yan¹, Jitao Lv², Yuanbi Yi³, Xu Ma⁴, Guoqing Zhang⁵, Shaofeng Wang⁶, Xiangfeng Zeng⁷, Yongfeng Jia⁸

Affiliations

¹ Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
² State Key Laboratory of Environmental Chemistry and Ecotoxicology, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
³ Department of Ocean Science and the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong, Hong Kong SAR 00852, China.
⁴ College of Environment and Resources, Dalian Minzu University, Dalian, Liaoning 116600, China.
⁵ Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, Xinxiang 453007, China.
⁶ Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China. Electronic address: swang@dlut.edu.cn.
⁷ Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. Electronic address: zengxf@iae.ac.cn.
⁸ Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.

PMID: 38583612
DOI: 10.1016/j.scitotenv.2024.172134

Abstract

Sediment-adsorbed Dissolved Organic Matter (SDOM) in coast plays a crucial role in the terrestrial and marine carbon cycle processes of the global environment. However, understanding the transport dynamics of SDOM along the coast of China, particularly its interactions with sediments, remains elusive. In this study, we analyzed the δ¹³C and δ¹⁵N stable isotopic compositions, as well as the molecular characteristics of SDOM collected from coastal areas spanning the Bohai Sea (BS), Yellow Sea (YS), East China Sea (ECS), and South China Sea (SCS), by using isotope ratio mass spectrometry and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS). We identified the predominant sources of carbon and nitrogen in coastal sediments, revealing terrigenous origins for most C and N, while anthropogenic sources dominated in the SCS. Spatial variations in SDOM chemodiversity were observed, with diverse molecular components influenced by distinct environmental factors and sediment sources. Notably, lignins and saturated compounds (such as proteins/amino sugars) were the predominant molecular compounds detected in coastal SDOM. Through Mantel tests and Spearman's correlation analysis, we elucidated the significant influence of spatial environmental factors (temperature, DO, salinity, and depth) and sediment sources on SDOM molecular chemodiversity. These findings contribute to a more comprehensive understanding of the carbon cycle dynamics along the Chinese coast.

Keywords: Coast of China; FT-ICR-MS; Sediment-adsorbed DOM molecule; Stable isotopes.