Data/hora: 09/06/2024 13:49:32

Provedor de dados: | Institutional Archive of Ifreme (ArchiMer)
País: | France
Título: | Les apports organiques et leur transformation en milieu abyssal à l'interface eau-sédiment dans l'Océan Atlantique tropical
Autores: | Khripounoff, Alexis; Rowe, Gilbert T.
Data: | 1985
Ano: | 1985
Palavras-chave: | Milieu abyssal; Flux particulaire; Bilan d'énergie; Biochimie des particules et des sédiments; Atlantique tropical; Deep-sea; Particles flux; Tropical atlantic; Energy budget; Biochemitry of particles and sediments.
Resumo: | Five particle traps were deployed at depths of 4 400 to 4 900 rn at two stations on the Demerara abyssal plain and one station on the Cape Verde abyssal plain (tropical Atlantic). At the same time, an intensive sampling of superficial sediments was carried out using a 0,25 m2 box corer. The total particle flux varied from 372 to 87,7 mg dry weightfm2/day. The average concentration of organic carbon was 40 mg/g of material collected. ln the surface sediment this was only 4 mg/g. A direct relationship existed between the intensity of the flux of organic matter and the richness of the organic matter of the deposited sediment. According to our calculations, more than 90% of the organic matter arriving at the bottom is consumed by the abyssal benthos and only 1% is lost to permanent sediment deposits. For 100 calories consumed by the benthos, 99 are utilized by the infauna and flora, 0, 7 by the holothurian egafauna and 0,3 by near-bottom fisches.  The biochemical composition of the particles is characterized at ali stations by a predominance of "humic" material in the total organic matter (more than 55%). The part of the molecules unaltered form living material varied from on station to another: for the most oceanic station the protein dominated, composing 20% of the total energy. At the station onder the influence of the continent the lipid fraction grew and was almost equal to that of the protein. ln this case, the carbohydrate fraction was very weak (7% of the organic matter). Finally the preference of the animais which feed on the particles is principally for the most energetic (lipid) and the most easily hydrolysable (labile protein) molecules: the other molecules, such as the humic matter, are less preferred, although they still contribute to about half of the energy consumed by the abyssal benthic animais.
Tipo: | Text
Idioma: | Francês
Identificador: | http://archimer.ifremer.fr/doc/00112/22318/19991.pdf
Editor: | Gauthier-Villars
Relação: | http://archimer.ifremer.fr/doc/00112/22318/
Formato: | application/pdf
Fonte: | Oceanologica Acta (0399-1784) (Gauthier-Villars), 1985 , Vol. 8 , N. 3 , P. 293-301
Fonte: | Gauthier-Villars