Caracterização da composição do plâncton em viveiros de piscicultura na Estação de Piscicultura Continental Johei Koike (UFRPE)

Abstract

An aquatic environment for the rational creation of fish has its own complex ecology, where the dynamics of biological and physical-chemical processes determine the conditions of water quality. Planktonic communities represent a sensitive tool to monitor environmental variations, such as indicators of water quality, levels of pollution and eutrophication, as well as important food sources for the trophic chain. The objective was to investigate the planktonic community of three active fish ponds in a diversion system and identify patterns in this community. Weekly water collections were carried out in three active fish ponds, at the Professor Johei Koike Aquaculture Station located on the headquarters of the Federal Rural University of Pernambuco (UFRPE). A superficial horizontal trawl was performed in each pond, with a plankton net with a mesh opening of 64 μm. The plankton samples were preserved in 70% alcohol and analyzed at the Zooplankton Laboratory of the Department of Oceanography at UFPE. The identification took place at the taxonomic level of large groups. For the three ponds, the water transparency was always below 25cm, decreasing from ponds 1 to 3 and in general the temperature was always between 28 and 29°C. Thus, a low variety of plankton species was observed in the ponds. Phytoplankton populations did not show great variations, in the three ponds the phylum Chlorophyta was the group of algae with the highest number of cells. On the other hand, zooplankton varied between ponds according to the type of fish cultivated and trophic conditions, the phylum Rotifera was in greater number in the three ponds, however, with abundance in relation to the other species in pond 3. that water quality parameters and the type of fish farmed appear to be the main factors controlling plankton populations in ponds.