Diversity and Structure of Pelagic Zooplankton (Crustacea, Rotifera) in NE Poland

Abstract

This study presents the diversity and structure of pelagic zooplankton in north-eastern Poland. The research was conducted in 47 lakes with different trophic conditions in the middle of summer. Samples were collected close to the deepest part of the lakes to avoid the diverse benthic and littoral zones. We found 119 zooplankton species of which 32 were Cladocera, 16 were Cyclopoida, 4 were Calanoida, and 67 were Rotifera. We determined which species occurred most frequently in the region, as well as the species that were characteristic of different trophic conditions. We also recorded the presence of eight cold-adapted species which some of them are considered as glacial relicts (e.g., Eurytemora lacustris, Heterocope appendiculata, Cyclops lacustris). Our research revealed potential glacial refugia for planktonic species in 14 lakes of NE Poland. Our study suggests that the presence of stenotherm species may be an excellent indicator of the ecological status of deep lakes and could be considered in lake monitoring programs. Furthermore, we did not find Bythotrephes longimanus which has been reported from Poland. Instead, we found that B. brevimanus was the most common representative of the genus in the study area.

First Insight into Groundwater Copepods of the Polish Lowland

“…Among stygoxenes were Chydorus sphaericus, Eudiaptomus gracilis, and Thermocyclops crassus. These species were present as a single record or in low numbers in groundwater, but they are very common in different types of surface water bodies in this region [18,19], north-western Poland [20], and Europe [21,22]. Therefore, these species seem to be accidental taxa temporarily imported from the surface.…”

“…The genus Diacyclops, comprising a large number of stygobiontic species [36,37], was represented by two species in our samples; both were classified as stygophiles. Diacyclops bisetosus was found in seven wells in different regions, whereas in surface water bodies in Poland it is found occasionally in low numbers [19,20]. However, D. bisetosus is a cosmopolitan, but probably cryptic species widely distributed in Europe [22].…”

Assessment Potential of Zooplankton to Establish Reference Conditions in Lowland Temperate Lakes

“…Collotheca pelagica, with a high and significant IndVal of 0.583, is clearly related to the reference conditions, although it has not been listed as an indicatory species before. However, Karpowicz and Ejsmont-Karabin [58] showed that the abundance of this species was higher in the low trophic conditions. The contribution of Collotheca pelagica and Ascomorpha ecaudis was significant in the differentiation between the reference and non-reference lakes based on SIMPER analysis.…”

Epizoic Rotifers and Microcrustaceans on Bivalves of Different Size and Behavior

“…m 2 ), water taken from eutrophic Lake Jorzec. Lake Majcz Wielki is a dimictic mesotrophic lake with surface area of 164 ha and maximum depth of 16.4 m [22]. Lake Jorzec is a eutrophic stratified lake with surface area of 42 ha and maximum depth of 11.6 m [23].…”