Spartina maritima (cordgrass) rhizosediment extracellular enzymatic activity and its role in organic matter decomposition processes and metal speciation
Duarte, B.; Almeida, P.R.; Caçador, I. (2009). Spartina maritima (cordgrass) rhizosediment extracellular enzymatic activity and its role in organic matter decomposition processes and metal speciation. Mar. Ecol. (Berl.) 30(s1): 65-73. https://dx.doi.org/10.1111/j.1439-0485.2009.00326.x
In: Marine Ecology (Berlin). Blackwell: Berlin. ISSN 0173-9565; e-ISSN 1439-0485, more
Also appears in:(2009). Proceedings of the 43rd European Marine Biology Symposium, The Azores Islands (Portugal), 8-12 September 2008. European Marine Biology Symposia, 43. Marine Ecology (Berlin), 30(Suppl. 1). 202 pp., more
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Keyword |
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Author keywords |
Extracellular enzymatic activity; metal speciation; salt marsh; sediment |
Authors | | Top |
- Duarte, B.
- Almeida, P.R.
- Caçador, I.
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Abstract |
Seasonal monitoring was carried out to investigate the influence of extracellular enzymatic activity (EEA) on metal speciation and organic matter cycling in the rhizosediment of Spartina maritima. Heavy metal speciation was achieved by the Tessier scheme, and showed a similar pattern of variation of the organic-bound fraction, indicating a decomposition process in progress. Both humic acid and organic matter showed the same seasonal pattern. The basal respiration of the rhizosediments also presented a similar seasonal pattern, indicating a microbial degradation of organic matter. The high organic-bound fraction found in the summer gradually decreased towards the winter. This decrease was found to be related to the increase of activity of peroxidase, ß-N-acetylglucosaminidase and protease. Also the activity of sulphatase was found to be related to the depletion on the exchangeable fraction, probably due to sulphide formation and consequent mobilization. The results show an interaction between several microbial activities, affecting metal speciation. |
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