Macrozoobenthic communities of Arctic soft bottoms: Structure and importance as food source for demersal fishes (in German)

• Main Author: Herrmann, Marko
• Format: Thesis
• Language: unknown
• Published: 2004
• Subjects: Arctic; Svalbard; Kongsfjord*; Kongsfjorden
• Online Access: https://epic.awi.de/id/eprint/10557/; https://epic.awi.de/id/eprint/10557/1/Her2004a.pdf; https://hdl.handle.net/10013/epic.21034; https://hdl.handle.net/10013/epic.21034.d001

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 200 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 deep-watercommunity 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 ...