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| Titel |
The influence of vent fluid chemistry on trophic structure at two deep-sea hydrothermal vent fields on the Mid-Cayman Rise |
| VerfasserIn |
Sarah Bennett, Cindy Van Dover, Max Coleman |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250089719
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| Publikation (Nr.) |
 EGU/EGU2014-3929.pdf |
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| Zusammenfassung |
| The two known deep-sea hydrothermal vent fields along the Mid-Cayman Rise are separated
by a distance of only 21 km, yet their chemistry and faunal diversity are distinct. The deeper
of the two vent fields, Piccard (with active venting from Beebe Vents, Beebe Woods and
Beebe Sea), at 4980 m is basalt hosted. The shallower vent field, Von Damm, at 2300 m
appears to have an ultramafic influence. The Von Damm vent field can be separated into two
sites: The Spire and The Tubeworm Field. The dominant vent fluids at the Tubeworm Field
are distinct from those at the Spire, as a result of fluid modification in the sub-surface. Von
Damm and Piccard vent fields support abundant invertebrates, sharing the same
biomass-dominant shrimp species, Rimicaris hybisae. Although there are some other shared
species (squat lobsters (Munidopsis sp.) and gastropods (Provanna sp. and Iheyaspira
sp.)) between the vent fields, they are much more abundant at one site than the
other.
In this study we have examined the bulk carbon, nitrogen and sulfur isotope composition
of microbes and fauna at each vent field. With these data we have deduced the trophic
structure of the communities and the influence of vent fluid chemistry. From stable isotope
data and end-member vent fluid chemistry, we infer that the basis of the trophic
structure at Piccard is dominated by sulfur, iron, and hydrogen-oxidizing microbial
communities. In comparison, the basis of the Von Damm trophic structure is dominated
by microbial communities of sulfur and hydrogen oxidizers, sulfate reducers and
methanotrophs. This microbial diversity at the base of the trophic structure is a result of
chemical variations in vent fluids and processes in the sub-surface that alter the
vent fluid chemistry. These differences influence higher trophic levels and can be
used to explain some of the variability as well as similarity in fauna at the vent
sites.
Part of this work was performed at the Jet Propulsion Laboratory, California Institute of
Technology, under contract with National Aeronautics and Space Administration (NASA). |
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