Factors controlling phyto plankton production and succession in a highly eutrophic lake kinnego bay lough neagh part 1 the phyto plankton community and its environment
Journal of Ecology 65(2): 547-560
ISSN/ISBN: 0022-0477 Accession: 005441197
The seasonal variation during 1973 and 1974 of phytoplankton and some physical and chemical conditions in Kinnego Bay, a shallow highly eutrophic part of Lough Neagh, N Ireland, are described. The shallow water column was always well-mixed, and vertical heterogeneity with respect to temperature and oxygen saturation was slight. The annual loading of algal nutrients was very great, but concentrations could be low as a result of depletion by the large algal growths. Diatoms, especially Stephanodiscus hantzschii, were dominant in the phytoplankton community during spring and autumn, but blue-green algae predominated during summer. Peak crops of both chlorophyll a (240 mg/m3) and algal volume (60 mm3/l) were extremely high. Apparent changes in algal standing crop were found to be highly dependent on the form in which the algal biomass was expressed. In view of the high loading of nutrients into the bay, it is suggested that the annual succession of phytoplankton species was not entirely attributable to nutritional considerations, but was at least partly a response to changing physical conditions.