|Composition of organic sulfur in riverine and marine sediments: Insights from sulfur stable isotopes and XANES spectroscopy|
|Zhu, MX; Chen, LJ; Yang, GP; Huang, XL; Zhao, YD; Zhao YD(赵屹东)
|摘要||Sulfur isotopes and X-ray absorption near edge structure (XANES) spectroscopy were combined to characterize/compare three operational organic sulfur (OS) pools, i.e. fulvic acid sulfur (FA-S), humic acid sulfur (HA-S) and non-chromium reducible organic sulfur (non-CROS) in marine [the East China Sea (ECS) and Jiaozhou Bay (JZB)] vs. riverine [Yangtze River (YR) and JZB tributaries] sediments. XANES results indicate that in marine sediments high valency S was the dominant OS functionality in both HA -S and FA -S, while non-CROS was dominated by low valency OS (80-92%). In the riverine sediments FA -S was dominated by high valency OS, while the average fractions of low and high valency OS in HA -S were comparable. The isotopic composition of FA-S (634SFA-s) and HA-S (634SuA-s) indicated that a substantial fraction of sulfide was incorporated into FA via sulfurization in the marine sediments, whereas terrigenous OS was almost the sole important source of HA -S. Compared with the ECS sediments, JZB sediments had more depleted 34SFA_s and a higher fraction of highly reduced FA -S due to eutrophication induced sulfurization. Relative to riverine FA -S, substantial sulfurization had not resulted in an increase in the fraction of highly reduced FA -S in marine sediments. This implies that the terrestrial systems may be much more favorable for the formation and/or preservation of highly reduced biogenic FA -S than the marine settings. The fraction of highly reduced HA -S in the JZB and its tributaries was similar, whereas the fraction was much lower in the ECS than in the YR. This indicates that highly reduced HA -S moieties in the YR may have been subject to extensive mineralization loss during transport in the large riverine/estuarine system, whereas the process in the JZB tributaries may be much weakened due to a relatively small catchment area. Distinct differences in isotopic and structural composition between humic-S (FA-S + HA-S) and non-CROS in the ECS sediments indicate that a combination of S isotopes and S-XANES is needed for characterizing the two operational pools for a better understanding the nature of OS in the ocean. (C) 2016 Elsevier Ltd. All rights reserved.|
East China Sea
; NEAR-EDGE STRUCTURE
; EAST CHINA SEA
; EARLY DIAGENETIC FORMATION
; EUTROPHIC JIAOZHOU BAY
; SOIL HUMIC SUBSTANCES
; ESTUARINE SEDIMENTS
; INORGANIC SULFUR
|WOS类目||Geochemistry & Geophysics
Zhu, MX,Chen, LJ,Yang, GP,et al. Composition of organic sulfur in riverine and marine sediments: Insights from sulfur stable isotopes and XANES spectroscopy[J]. ORGANIC GEOCHEMISTRY,2016,99:102-112.
Zhu, MX,Chen, LJ,Yang, GP,Huang, XL,Zhao, YD,&赵屹东.(2016).Composition of organic sulfur in riverine and marine sediments: Insights from sulfur stable isotopes and XANES spectroscopy.ORGANIC GEOCHEMISTRY,99,102-112.
Zhu, MX,et al."Composition of organic sulfur in riverine and marine sediments: Insights from sulfur stable isotopes and XANES spectroscopy".ORGANIC GEOCHEMISTRY 99(2016):102-112.