Makrozoobenthos- Gemeinschaften arktischer Weichböden: Struktur und Bedeutung als Nahrungsgrundlage demersaler Fische
Herrmann, M. (2004). Makrozoobenthos- Gemeinschaften arktischer Weichböden: Struktur und Bedeutung als Nahrungsgrundlage demersaler Fische. MSc Thesis. Christian-Albrechts-Universität: Kiel. 96 pp. |
Keywords | Aquatic communities > Benthos > Zoobenthos Aquatic organisms > Marine organisms > Fish > Marine fish Composition > Community composition Food webs > Food chains PN, Arctic [Marine Regions] Marine/Coastal |
Abstract | The focus of the present study was to investigate the soft bottom community (including in- and epifauna) at the coastal slope (5 m to 30 m) in Kongsfjorden, and to estimate its importance as food source for demersal fish. For these purposes the macrozoobenthos was sampled at six sampling locations. In total 30 samples were taken (6 x 5 replicates) by means of a steel frame of 192 cm2 area size. A suction pump („airlift“) collected the soft bottom fauna within the designated area. Polychaets (84 %), molluscs (10 %) and crustaceans (3 %) dominated the soft bottom community. In total, 63 species were found, including 30 species which have not been recorded in Kongsfjorden earlier. Seven species have not yet been recorded for the entire archipelago of Svalbard (according to Gulliksen et al. 1999). The average abundance was 6293 individuals m-2, the average biomass was 14 g ash free dry mass (afDM) m-2. Three community types could be identified by means of cluster analysis and multidimensional scaling: The „shallow water“ - community at 5 m (28 species; 2260 individuals m-2; 3.5 g m-2 afDM), the „mid-water“- community between 10 m and 20 m (51 species; 7184 individuals m-2; 20.7 g m-2 afDM) and the deepwater“- community in the range of 25 m and 30 m (44 species; 6982 individuals m-2; 10.6 g m-2 afDM). The species found were then categorized with respect to their feeding ecology and were classified to their zoogeography. Five species were omnivorous, 23 carnivorous, 25 detritivorous and 18 suspesion feeders. Most of the species (34) were arctic-boreal followed by cosmopolitan species (20); only five species were true arctic. Furthermore ecological indices were calculated: the Margalef Index (1.45°-°2.23), Shannon-Wiener diversity (1.85°-°2.19) and evenness (0.67°- °0.82). Six dominant species (> 10 %) were identified (Crassicorophium crassicorne, Chaetozone setosa, Dipolydora quadrilobata, Euchone analis, Scoloplos armiger and Spio armata) and three were determined as indicator species (Dipolydora quadrilobata, Euchone analis and Scoloplos armiger). Nine species of demersal fish were found in shallow areas (5 m to 30 m) of Kongsfjorden: Anarhichas lupus, Anisarchus medius, Eumicrotremus derjugini, Gadus morhua, Gymnacanthus tricuspis, Leptoclinus maculatus, Liparis liparis, Lumpenus lampretaeformis and Myoxocephalus scorpius. According to the literature these fish species were feeding on the bottom community, in particular on taxa witch found at this study Priapulus caudatus, Scoloplos armiger, Anonyx sarsi, Crassicorophium sp., Ischyrocerus sp., Monoculodes tesselatus, Onisimus edwardsi, Sclerocrangon boreas and Ophiura sarsi. Polychaets (up to 87 %), amphipods (up to 56 %), molluscs (up to 50 %) and echinoderms (up to 48 %) dominated the spectrum of food source. |
Dataset | - Herrmann, M., J. Laudien, 2004: Soft bottom community structure and diversity in Arctic Kongsfjorden. Alfred-Wegener-Institute for Polar and Marine Research, Bremerhaven, Germany, more
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