Composition and seasonal variation of the zooplankton in the Limfjord (Denmark) during 1973–1974

Publisher Website
Google Scholar
Abstract
From November 1973 to November 1974 the zooplankton in the Limfjord was sampled monthly at two stations with three different nets. The samples were subsampled and quantified, all animals were identified mainly to the species level and counted, and the numbers calculated per m3 sea water. The differences in ability of the three nets in catching different taxonomie groups are demonstrated. The seasonal changes in dominance of different species and groups and the changing relationship between holo- and meroplankton during the year are described. The dominating meroplanktonic species were Modiolus modiolus, Aloidis gibba, Polydora ciliata, Balanus balanus, and Balanus crenatus. The most abundant holoplanktonic species were Synchaeta spp., Oitbona similis, Acartia clausi, Temora longicornis, Centropages hamatus, and Pleopis polyphemoides. Based on the ecology of the most abundant species, the composition of the zooplankton in the fjord can be characterized as a diluted edition of the North Sea plankton. The degree of dilution increases from the western to the eastern part of the fjord, following both a decreasing salinity gradient and an increasing annual variation in salinity.