Distribution of abundance, biomass, production and productivity of macrozoobenthos in the Sub-Antarctic Magellan Province (South America)

• Main Authors: Thatje, S., Mutschke, E.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 1999
• Subjects: Antarc*; Antarctic; Polar Biology; Weddel Sea
• Online Access: https://epic.awi.de/id/eprint/3097/; https://epic.awi.de/id/eprint/3097/1/Tha9999c.pdf; https://hdl.handle.net/10013/epic.13681; https://hdl.handle.net/10013/epic.13681.d001

Distribution of abundance, biomass, productivity and production of macrozoobenthos was investigated in four study areas in the Magellan region(South Patagonian Ice-Field, Strait of Magellan, Beagle Channel. Continental Shelf). Using a Reineck box corer and a multibox corer, a total of 277 quantitative benthos samples were taken at 78 stations in water depths between 8 and 1139 m during the Joint Chilean-German Italian Magellan "Victor-Hensen Campaign" in 1994 the "Polarstern" expedition ANT XIII/4 in 1996 and the Chilean expeditions "Cimar Fiordo II + III" in 1996 and 1997, respectively, on board RV "Vidal Gormaz" Mean abundance in the South Patagonian Ice-Field was significantly lower than in the Strait of Magellan and the Beagle Channel. Biomass and abundance decreased clearly with depth (20-300 m to 700-1 500 m: 3.9 gC /m super(2) to 0.6 gC/m super(2); 2832 ind./m super(2) to 569 ind./m super(2)). Average abundance, biomass and production of the whole Magellan region are lower (2318 ind./m super(2), 3.2 gC/m super(2), 0.62 gC/m super(2) /year) than in the high Antarctic Weddel Sea. In the Magellan region, macrozoobenthos composition of abundance is mainly dominated by polychaetes (56 %), followed by arthropods (16 %), echinoderms (10 %) and molluscs (11 %). Comparisons of our present results with those of high Antarctic areas make it clear that the Magellan region has a transitional character.