Composition chimique élémentaire (C, H, N) et équivalent énergie d'Acartia clausi(Crustacea: Copepoda), espèce importante dans la bioénergétique des écosystèmes côtiers de Méditerranée nord-occidentale

✍ Scribed by P. Kerambrun

• Publisher: Springer-Verlag
• Year: 1987
• Tongue: English
• Weight: 794 KB
• Volume: 95
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00447492

✦ Synopsis

Elementary chemzcal composition (C, H, N) and energy equivalent of A cartm clausz (Crustacea: Copepoda), an important specws m the bioenergeucs of the coastal ecosystems of the northwest Medtterranean

Carbon, hydrogen and nitrogen content were investigated in natural populations of the crustacean copepod Acartia clausi collected during 1980-1982 from different areas near Marseilles, France -the coastal area of Cortiou which receives waste waters from the Marseilles Conurbation; the eutrophic and polluted Golfe de Fos, with its open basins; and the offshore areas of the Marseilles' Gulf. Energy equivalents were determined in order to examine the ecological role ofA. claust from a bloenergetlc point of view. Carbon content ranged from 38.9% of body dry weight (DW) in the open sea off Marseilles to 45.5% of DW an an open basin at Fos in winter, mtrogen content from 10.4% of DW in the open sea off Marseilles in winter to 13.6% of DW in the open basins at Fos m summer

These values agree with the ranges reported m the literature for non-lipidic copepods. Carbon to mtrogen ratios ranged between 3.22 and 3.80. In the open basins at Fos, the mean value in summer (3.30) was significantly different from that in winter (3.70). In the Cortiou area, no seasonal differences emerged. For the three areas, energy equivalents ranged from 4.28 to 5.00 cal mg -1 DW. Highest values were recorded for the populations of the Cortiou area and of the open basins at Fos, i.e., from environments where particulate organic matter is abundant and relatively invariable. In these populatmns, the energy equivalent per unit dry weight did not change significantly throughout the year. The values recorded agreed with the means reported in the hterature for non-hpldlc species, but were far below those recorded for species which are able to store hpids A clausi is one of the most abundant copepod species throughout the year in the plankton of these coastal areas, and its steady energy content, with little seasonal variation, makes it an important element m the bioenergetics of the northwest Mediterranean coastal ecosystems.