8 and 4 2% of the total rotifers and total zooplankton) respectiv

8 and 4.2% of the total rotifers and total zooplankton) respectively. During autumn, the zooplankton showed a smaller peak than in summer, but practically the same groups and species were dominant, although they were present in smaller numbers (Figure 6). The zooplankton community was dominated by copepods (average: 22 263 individuals m−3, representing 82.8% of the total zooplankton), rotifers

(2078 individuals m−3, 7.7%) and molluscs (1160 individuals m−3, 4.3%). The leading species were the copepod O. nana (9017 individuals m−3 – 33.5% of the total zooplankton), P. crassirostris (6164 individuals m−3, 22.9%) and C. kroyeri (1195 individuals m−3, 4.4%) as well as the rotifer B. calyciflorus (1413 individuals m−3, 5.3%) and gastropod selleck products DAPT chemical structure veligers (1070 individuals m−3, 4%). The zooplankton standing crop was the smallest during winter (average: 8582 individuals m−3). The contribution of copepods to the total zooplankton decreased during winter, representing only 57% of the total zooplankton with an increase of their larval stages (forming 26.9 of the total zooplankton). Moreover, the dominant adult species were P. crassirostris (944 individuals m−3, 11% of the total zooplankton) and O. nana (767 individuals m−3, 8.9%). During this season, cladocerans were more numerous, forming the second most dominant group with an average density

of 2076 individuals m−3 (24.2% of the total zooplankton) ( Figure Montelukast Sodium 6). Podon polyphemoides, Moina micrura and Alona bukobensis represented the cladoceran population in the lake during winter, P. polyphemoides being dominant (average: 2072 individuals m−3, 24.1% of total zooplankton). Rotifers were prevalent during this season (1124 individuals m−3, 13.1% of the total community). The most common rotifer species was Brachionus plicatilis (11.2%). In spring, the zooplankton standing crop was larger than in winter (average: 11 776 individuals m−3). Copepods

represented 66.6% of the total zooplankton with an increase of their larval stage densities, making up 44.5% of the total zooplankton (average: 5242 individuals m−3). They were represented by 11 species with the dominance of O. nana (average: 1617 individuals m−3, 13.7% of the total zooplankton). Paracalanus crassirostris, C. kroyeri and E. acutifrons were frequent species. Rotifers were the second dominant group with an average density of 2638 individuals m−3, accounting for 22.4% of the total count. This percentage was relatively high in comparison with the other seasons. Regarding species composition, rotifers were more diversified (6 species). B. calyciflorus (78.8% of the total rotifers) and B. plicatilis (18%) were the dominant ones. Cladocerans (average: 492 individuals m−3) contributed about 4.2% to the total community. The most common cladoceran species was Podon polyphemoides, accounting for 3.9% of the total zooplankton with an average of 465 individuals m−3.

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