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| Titel |
Diversity and Characteristics of Benthic Foraminifera in Cold Seep Areas in the Active Margin of the northeastern South China Sea |
| VerfasserIn |
Meng-Ting Chiang, Ellen Thomas, Kuo-Yen Wei, Yu-Shih Lin, Saulwood Lin, Andrew Tien-Shun Lin |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250102978
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| Publikation (Nr.) |
 EGU/EGU2015-2380.pdf |
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| Zusammenfassung |
| The active continental margin in northeastern South China Sea (SCS) has been considered to
have high potential to be a reservoir of gas hydrate, based on geographic features,
geophysical evidences, as well as geochemical analyses of samples from the water column,
pore water and sediments. Compared to a typical sea floor area, cold seep areas have more
food for benthos and more diverse habitats. As a result, we can expect a higher
species diversity of benthic organisms in cold seep areas of the SCS. Based on
preliminary results of species identification of benthic foraminiferal assemblages
in the upper most sediments (0-5 cm) of box cores collected around cold seeps
at water depth ~1300m, the species diversity is significantly higher at seep sites
(Shannon-Wiener index = 274) than at background sites (Shannon-Wiener index
= 3). The faunal assemblages consist of ~68% calcareous benthic foraminifera
(CBF) and ~32% agglutinated benthic foraminifera (ABF) at seep sites. On the other
hand, faunal assemblages are composed of only ~24% CBF and ~76% ABF at
background sites. By staining the sample with rose Bengal-ethanol solution, we were
able to recognize in-situ individuals which were alive at the time of collection,
and separate them from dead specimens. Among the living individuals, the most
abundant CBF species in seep sites is Bulimina aculeata (~51% in the living CBF
fauna), followed by the typical “shelf-species,” Lenticulina inornata, (~10%) and the
common “brackish-species,” Miliolinella subrotunda, (~9%), while the most abundant
ABF species is Cribrostomoides subglobosus (~19% in the living ABF fauna). The
most common species thus are typical for shallower, more food rich environments. |
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