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The impact of zooplankton on carp production in Bohelov ponds
ŠINDLER, Martin
Zooplankton dynamics and the changing parameters of pond water in Bohelov ponds was monitored by regular sampling of zooplankton at approximately weekly intervals from April to October 2014 with sampling Schlott-Bauer method in a volume of 20 and 60 liters. The samples were divided into taxonomic groups and species, classified in so-called filterable zooplankton over 500 m. From the pond water parameters was monitored oxygen, pH, temperature, transparency and acid neutralizing capacity and their impact on production in ponds. Control fish out in each month showed a direct correlation with the increase in biomass Common carp (Cyprinus carpio) on the abundance of filterable zooplankton comparing the pond no. 1 and 3. Stocking was fed with feed wheat (Triticum) during the season. The abundance of zooplankton was different in different ponds and gradually changed by increasing fish stocking. A greater abundance of filterable zooplankton of Daphnia - Cladocera and lower species was noticed in the pond no. 1 as in the pond no. 3. With the increasing biomass of fish stocking has been demonstrated reduced of filtrable zooplankton where the number of small zooplankton (< 500 m) ind.l-1. Zooplankton was represented particularly by species Bosmina longirostris, Chydorus sphaericus, Daphnia galeata, D. parvula, D. ambigua. In order copepods - Copepoda were seen mainly nauplius and copepod stages of type Acanthocyclops americanus, rotifers were represented mainly by Brachionus sp. and Polyartha sp.. Increased abundance of filterable zooplankton has a impact on the final amount of biomass of fish stocking expressed by growth SGR (% .day-1) and a reduction coefficient relative FCR. Due to intensive farming combined with farming of poultry during the last decades has been observated accelerated eutrophication process of reducing the size of the littoral zone with a share of macrophytes.
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