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Microbial activity in sandy and muddy estuarine sediments 总被引：2，自引：0，他引：2
M. Elskens M. Leermakers S. Panutrakul F. Monteny W. Baeyens 《Geo-Marine Letters》1991,11(3-4):194-198
Striking differences were observed in the use of the electron acceptors involved in the degradation of organic matter by heterotrophic
bacterial activity between a muddy and a sandy sediment on the same tidal flat of the Scheldt estuary. These bio-reduction
reactions could have a quite different effect on the cycling of trace metals in the sediment as suggested by the results of
the mobilization experiments. Trace metal speciation can be described as a function of the redox potential, in view of the
fact that the latter is related to the heterotrophic bacterial activity. 相似文献
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Geochemical processes in muddy and sandy tidal flat sediments 总被引：2，自引：0，他引：2
W. Baeyens S. Panutrakul M. Elskens M. Leermakers J. Navez F. Monteny 《Geo-Marine Letters》1991,11(3-4):188-193
Different approaches, such as element analyses of the bulk sediment and of the fine sediment fraction (<63 μm), sequential
extraction techniques, correlation coefficient, and enrichment factor calculations, clearly demonstrate the differences in
geochemical behavior of a muddy and a sandy sediment on the same tidal flat in the Scheldt estuary (Belgium). The geochemical
processes in combination with the relatively large transport mobility of dissolved compounds due to the tidal action in the
sediment, created compound specific vertical distribution profiles. 相似文献
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Sulfate reduction rate (SRR) and pools of reduced inorganic sulfur, acid volatile sulfide (AVS), chromium reducible sulfur (CRS), and elemental sulfur (So), were studied from June 1990 till March 1992 at two locations on the Ballastplaat mudflat in the Scheldt estuary. The sediment composition at station A was mainly sand with low organic content whereas sediments at station B were dominated by silt and clay with high organic content. SRR was positively related to temperature; more pronounced at station B (Ea=190 kJ mol−1) than at station A (Ea=110 kJ mol−1). The maximum SRR values observed equalled 14 μmol cm−3 d−1 at station B and 1 μmol cm−3 d−1 at station A. AVS was the dominant radiolabelled end product of the sulfate reduction reaction, except in surface sediments where pyrite and So were more dominant. However, CRS was the predominant reduced inorganic sulfur pool in the sediments. Both AVS and CRS pools showed temporal variations out of phase with SRR. SRR peaked in summer, while the concentrations of AVS and CRS were highest in fall. The accumulation of AVS and CRS started late summer after depletion of oxidants, which had accumulated during winter and spring. The estimated annual SRR and thus sulfide production in the upper 15 cm of station B was of the order of 100 mol m−2 yr−1, and at station A of the order of 12 mol m−2 yr−1. The sulfur mass balance shows that only a very small fraction, if any, of the produced sulfide is retained as reduced inorganic sulfur in the sediment. 相似文献
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