Caracterização da comunidade zooplanctônica e sua relação com a qualidade da água da estação de piscicultura da UHE-Pedra do Cavalo, Cachoeira, Bahia

Abstract

The study was carried out at Pedra do Cavalo fish farm, Cachoeira, Ba, with weekly collections in the months of September and November, totaling 6 samples. Sampling time refers to the development time of the larvae to the stage of the fingerlings, when they are ready to be marketed. The physical-chemical and biological parameters of the water were collected as: temperature, dissolved oxygen, pH, electrical conductivity, ammonia, nitrite, total phosphorus and chlorophyll a of three tanks and drainage and water channels for comparison between locations. The zooplanktonic colonization was also recorded and identified at species level for cladocerans and rotifers groups and at the large group level for the copepods, the collection of these organisms was done through a plankton net. Some physico-chemical parameters were collected in situ with the use of a multiparameter probe. Water samples were collected for analysis of ammonia, nitrite, phosphorus and chlorophyll a in the laboratory. The sites studied were classified as supereutrophic and hypereutrophic according to the Trophic State Index. A dominance of the rotifer group was verified in the sampled places, a group frequently associated with eutrophication of water bodies. Among copepods, nauplii and copepodite forms were more frequent than adult forms.