|Seasonal variations in composition and production of planctonic communities in the lower River Rhine|
|Admiraal, W.; Breebaart, L.; Tubbing, G.M.J.; van Zanten, B.O.; de Ruijter van Stevenick, E.D.; Bijkerk, R. (1994). Seasonal variations in composition and production of planctonic communities in the lower River Rhine. Freshwat. Biol. 32: 519-531|
|In: Freshwater biology. Blackwel Scientific Publications/Blackwell Scientific Publications: Oxford. ISSN 0046-5070, more|
Biological production; Community composition; Lotic environment; Nannoplankton; Phytoplankton; Plankton surveys; Seasonal variations; Zooplankton; Fresh water
|Authors|| || Top |
The composition and activity of phytoplankton, zooplankton and bacterioplankton in the lower River Rhine were measured in 1990 as part of an international biological inventory of the river. Phytoplankton blooms, dominated by a few species of centric diatoms, declined one order of magnitude during downstream transport. During non-bloom conditions algal densities were maintained during transport, or increased slightly, indicating the suitability of the river reach for algal growth. Bacterial cell number and production showed a broad summer maximum with activity peaks coincident with declining phytoplankton blooms. Winter values of bacterial production were substantial, probably as a result of allochthonous input of organic matter. Rotifers and crustaceans made up the greater part of the zooplankton biovolume, but at the upstream station the contribution of Dreissena larvae and rhizopods was also substantial.