Spartina maritima (cordgrass) rhizosediment extracellular enzymatic activity and its role in organic matter decomposition processes and metal speciation

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Duarte, B (Author) Other; Pedro Almeida (Author) Other; Cacador, I (Author) Other

Journal

Title: Marine Ecology

Vol. 30

Pages: 65-73

ISSN: 0173-9565

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 26 Citations

Scopus - 34 Citations

Other information

Authenticus ID: P-003-FH1

DOI: 10.1111/j.1439-0485.2009.00326.x

Abstract (EN): 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, beta-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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9