The Diversity, Biomass and Production of Zooplankton in Lake Inarijaervi

About 650 zooplankton samples were collected from Lake Inarijaervi in 1977-1979 from the littoral and pelagial zones of the lake. One hundred and twenty-three zooplankton taxa were found and most of them can be considered euplanktonic. The most important species were Holopedium gibberum, Daphnia cristata, Cyclops spp. and Eudiaptomus spp. Mean pelagial zooplankton biomass was 0.29 g m super(-3) in the 0-5 m depth zone, 0.17 g m super(-3) in 5-10 m and 0.11 g m super(-3) in 10-20 m. The zooplankton biomass at a sandy shore was about 0.09 g m super(-3), at a stony shore 0.05 g m super(-3) and at a vegetated shore 0.76 g m super(-3). About 70% of the whole zooplankton production consisted of crustaceans. The sum of herbivore and carnivore zooplankton production in the pelagial area during the summer was 210-330 kg ha super(-1) x 3 months.