Seasonal and long-term population fluctuations of Diastylis rathkei (Crustacea: Cumacea) of Kiel Bay and German Bight
Rachor, E.; Arntz, W.E.; Rumohr, H.; Mantau, K.-H. (1982). Seasonal and long-term population fluctuations of Diastylis rathkei (Crustacea: Cumacea) of Kiel Bay and German Bight. Neth. J. Sea Res. 16: 141-150
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579; e-ISSN 1873-1406, more
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| Authors | | Top |
- Rachor, E., more
- Arntz, W.E.
- Rumohr, H., more
- Mantau, K.-H.
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| Abstract |
Populations of Diastylis rathkei from muddy bottom areas in Kiel Bay and the German Bight have been investigated over a period of more than 10 years. The observed seasonal and long-term changes in abundance, biomass and production are discussed in relation to hydrographical differences. Long-term annual mean numbers per m² are about 500 in Kiel Bay and 450 in the German Bight. Mean biomass (ash-free dry weight) is 0.64 g. m-2 in Kiel Bay compared to 0.71 g. m-2 in the German Bight, the corresponding production values being 1.7 and 2.3 g .m-2 .a-1 due to the better growth in the German Bight. Annual P/B ratios are 2.7 and 3.2 respectively. The production estimates suggest the importance of Diastylis in the demersal food web. Both populations are mainly controlled by physical factors, in particular by low winter temperatures. |
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