Subsurface microbiology and biogeochemistry of a deep, cold‐water carbonate mound from the Porcupine Seabight (IODP Expedition 307)
Open Access
- 2 January 2009
- journal article
- Published by Wiley in Environmental Microbiology
- Vol. 11 (1), 239-257
- https://doi.org/10.1111/j.1462-2920.2008.01759.x
Abstract
The Porcupine Seabight Challenger Mound is the first carbonate mound to be drilled (∼270 m) and analyzed in detail microbiologically and biogeochemically. Two mound sites and a non-mound Reference site were analyzed with a range of molecular techniques [catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH), quantitative PCR (16S rRNA and functional genes, dsrA and mcrA), and 16S rRNA gene PCR-DGGE] to assess prokaryotic diversity, and this was compared with the distribution of total and culturable cell counts, radiotracer activity measurements and geochemistry. There was a significant and active prokaryotic community both within and beneath the carbonate mound. Although total cell numbers at certain depths were lower than the global average for other subseafloor sediments and prokaryotic activities were relatively low (iron and sulfate reduction, acetate oxidation, methanogenesis) they were significantly enhanced compared with the Reference site. In addition, there was some stimulation of prokaryotic activity in the deepest sediments (Miocene, > 10 Ma) including potential for anaerobic oxidation of methane activity below the mound base. Both Bacteria and Archaea were present, with neither dominant, and these were related to sequences commonly found in other subseafloor sediments. With an estimate of some 1600 mounds in the Porcupine Basin alone, carbonate mounds may represent a significant prokaryotic subseafloor habitat.Keywords
This publication has 73 references indexed in Scilit:
- Age constraints on the origin and growth history of a deep-water coral mound in the northeast Atlantic drilled during Integrated Ocean Drilling Program Expedition 307Geology, 2007
- Morphology and environment of cold-water coral carbonate mounds on the NW European marginInternational Journal of Earth Sciences, 2006
- Microbial methane turnover at mud volcanoes of the Gulf of CadizGeochimica et Cosmochimica Acta, 2006
- Thérèse Mound: a case study of coral bank development in the Belgica Mound Province, Porcupine SeabightInternational Journal of Earth Sciences, 2005
- The Magellan mound province in the Porcupine BasinInternational Journal of Earth Sciences, 2005
- Quantitative analysis of bacterial communities from Mediterranean sapropels based on cultivation-dependent methodsFEMS Microbiology Ecology, 2004
- Giant carbonate mud mounds in the southern Rockall TroughMarine Geology, 2003
- A combined ecological and physiological approach to studying sulphate reduction within deep marine sediment layersJournal of Microbiological Methods, 1995
- Deep subsurface microbial processesReviews of Geophysics, 1995
- A computer program for the determination of most probable number and its confidence limitsJournal of Microbiological Methods, 1993