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Updated: Nov 29, 2025

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS
Published on: August 31, 2017
Conversion mechanisms between organic sulfur and inorganic sulfur in surface sediments in coastal rivers
Ming Jiang1, Yanqing Sheng2, Qunqun Liu1
1Research Center for Coastal Environment Engineering Technology of Shandong Province, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China; University of Chinese Academy of Sciences, Beijing, China.
Abstract:
Geochemical processes of sulfur (S) in river aquatic systems play a crucial role in environmental evolution. In this study, the distributions and sources of reduced inorganic sulfur (RIS) and organic sulfur (OS) in coastal river surface sediments were investigated. The results indicated that OS dominated total S (80%), and OS (i.e., humic acid sulfur, HAS; fulvic acid sulfur, FAS) correlated with the availability of labile organic matter (OM) and reactive iron (Fe). Terrigenous inputs and sulfurization contributed to the enrichment of FAS through the S reduction. Autochthonous biological inputs were potential sources of HAS from S oxidization. The X-ray photoelectron spectroscopy showed that the main sources of S in surface sediments were deposited as the form of organic ester-sulfate. Aquatic life could break S down further, producing reduced S compounds accumulated as thiols and RIS in anoxic sediments. RIS was dominated by acid volatile sulfur (AVS) and chromium (II)-reducible sulfur (CRS). Reactive Fe oxides were major control factors for the conversation from hydrogen sulfide (H2S) to AVS, whereas elemental sulfide (ES) controlled the conversion from AVS into CRS in coastal rivers.
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