Temporal evolution of deep-sea hydrothermal communities on a fast-spreading ridge as related to venting patterns: a review of observations
Desbruyères, D.; Segonzac, M. (1997). Temporal evolution of deep-sea hydrothermal communities on a fast-spreading ridge as related to venting patterns: a review of observations, in: Biologie des sources hydrothermales profondes = Biology of deep-sea hydrothermal vents: Journées d'échanges du Programme DORSALES = DORSALES Workshop Roscoff 6-8 octobre 1997. Cahiers de Biologie Marine, 38(2): pp. 122-123 In: (1997). Biologie des sources hydrothermales profondes = Biology of deep-sea hydrothermal vents: Journées d'échanges du Programme DORSALES = DORSALES Workshop Roscoff 6-8 octobre 1997. Cahiers de Biologie Marine, 38(2)[s.n.][s.l.]. 111-149 pp., more In: Cahiers de Biologie Marine. Station Biologique de Roscoff: Paris. ISSN 0007-9723; e-ISSN 2262-3094, more |  |
| Abstract | Observations during CYAMEX (1979) of large dead populations of the giant bivalve Calyptogena magnifica were the first indices of direct relationships between active venting and hydrothermal community survival. Since that time, scientists achieved multiyear surveys of active sites on Pacific Mid-Oceanic Ridges at different locations on the EPR and GSC. All these studies converge to demonstrate the temporal and spatial instabilities of the hydrothermal environment and the key role of the temporal variations on structuring the communities. An eruption occurred presumably in April 1991 and altered vent distribution and settings (Haymon et al., 1991) as well as existing biota. It was followed by a large diffuse venting and the development of extensive thick bacterial mats (Lutz et al., 1994). Some preexisting megafaunal populations were hurried (Haymon et al., 1991) or altered (personal observation) by new lava flows. One month after, piles of crabs (Bythograea thermydron) were observed grazing on bacterial mats and (?) dead animals. After six months, we observed a dramatic reduction in the quantity of bacteria restricted to vent areas. One year after the eruption, venting fissures were colonized by the vestimentiferan worm Tevnia jerichonana measuring up to 30 cm long. In December 1993, large number of giant tubeworms Riftia pachyptila have settled and tubes reached length in excess of 1.5 meter (Lutz et al., 1994). |
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