The hydrothermal vent community of a new deep-sea field, Ashadze-1, 12°58'N on the Mid-Atlantic Ridge
|Author(s)||Fabri Marie-Claire1, Bargain Annaelle2, Briand Patrick1, Gebruk A.3, Fouquet Yves4, Morineaux Marie1, Desbruyeres Daniel1|
|Affiliation(s)||1 : Ifremer Brest, Dept Etude Ecosyst Profonds, F-29280 Plouzane, France.
2 : Univ Nantes, Equipe Mer Mol & Sante, EA2160, F-44322 Nantes, France.
3 : Russian Acad Sci, PP Shirshov Oceanol Inst, Moscow 117997, Russia.
4 : Ifremer Brest, Dept Marine Geosci, F-29280 Plouzane, France.
|Source||Journal Of The Marine Biological Association Of The United Kingdom (0025-3154) (Cambridge Univ Press), 2011-02 , Vol. 91 , N. 1 , P. 1-13|
|WOS© Times Cited||41|
|Keyword(s)||hydrothermal vent, Mid-Atlantic Ridge, Maractis rimicarivora, isotopes|
|Abstract||Ashadze-1 (128 580N 448 510W, 4080 m) on the Mid-Atlantic Ridge (MAR) is the deepest known ctive hydrothermal vent ield. The first observations on this site were numerous clear and black smokers and surprisingly few nown symbiotic species ominant in other vent areas on the MAR. The species most abundant at Ashadze-1 are those usually ound at the periphery f hydrothermal communities: sea-anemones Maractis rimicarivora and chaetopterid polychaetes hyllochaetopterus sp. ov. This study comprised site mapping and faunal sampling and Ashadze-1 was completely mapped y using the Remote perated Vehicle ‘Victor 6000’ and a new high resolution tool available for deep-sea research. A photo-mapping survey was carried out with a long range optical black and white camera. Digitization of substrata and sea-anemones visible on the images was performed by GIS. Spatial distribution of Ma. rimicarivora was distinguished by high densities of 32 ind.m22 on the western side of the main smoker area. Submersible sampling operations allowed taxonomic identification within a 200 × 110 m area. Carbon, nitrogen and sulphur isotopic ratios were measured in four dominant species to identify their trophic position. The present paper gives the complete maps and describes the faunal community of the Ashadze-1 vent field. The results obtained led us to consider this site as an ecosystem in its declining stage. Finally we compare the similarities of this community to other hydrothermal communities on the northern MAR.|