RESEARCH ON THE PRODUCTION AND PRODUCTIVITY OF ZOOPLANKTON IN A FRESHWATER AQUATIC POOL
Valerica Gîlcă, I. Gîlcă
The complex hydrobiological investigations undertaken in Lake Ezareni Iasi in summer 2012 were conducted qualitative and quantitative determinations of zooplancton. Qualitative analysis of zooplankton samples was to determine the main taxon groups of zooplancteri (rotifers, copepods, cladocere) and to produce the conspect of faunal taxonomic groups. Quantitative analysis was performed for structural characterization of planktonic zoocenoza (density, abundance, biomass) by the gravimetric method, which consists in determining the wet weight of each species of zooplancters. They made lots of 100 individuals of the same species and have weighed the analytical balance. Was obtained as an average weight of each body of the species analyzed. With your average weight of each species could calculate the total biomass of zooplankton in water volume (liter). The results indicate that the composition of zooplankton was identified three taxonomic groups (Cladocere, Copepods, Rotifers), largest numerical density occurring in the upstream area of the lake area with 6104 ex./m3, followed by the center of Lake with 5454 ex./ m3 and finally in downstream area with a total of 3122 ex/ m3. Regarding the biomass highest values were registered at the cladocers in the central area of the basin investigated (920.82 g/m3), then at copepods in the upstream area (223 ex./m3), and the lowest value was recorded at rotifers in all three sectors of the basin investigated.
Key words: aquatic, zooplankton, biomass, density