STUDY OF LIMNOLOGICAL VARIABLES IN NURSERIES OF Colossoma macropomum (Cuvier; 1818) AND Pseudoplatystoma corruscans (Agassiz, 1829)

Abstract

Ecosystem's aquatic metabolism comprises three main levels: production, consumption and decomposition. For the aquaculture fundament the knowledge and accompaniment of the biotic and abiotic factors for a sustainable production. The study evaluated the dynamics of variables limnologics in ponds: Colossoma macropomun (CM) and Pseudoplatystoma corruscans (PC), during a 24hs. The work was accomplished in the Station of Fish farming of Chesf, Paulo Afonso-BA. The variables oxygen (O2), temperature (T°C) and pH were measured every two hours, shines and transparency. Samples of water were analysis ammonia, nitrite, nitrate, inorganic and organic phosphate, total phosphors, chlorophyll a, identification of the plankton and phytobenthos were collected at 09:00, 15:00 and 21:00hs. All the variables physical-chemistries were inside of the ideal for culture species. The group phytoplankton most frequent no CM was Cyanophyta and Bacillariophyta. while in PC was Xanthophyta. The group phytobentic most frequent no CM was Xanthophyta, while in PC was Bacillariophyta. The group of Copepods was the most evident zooplankton in CM and there was absence of Rotifers in PC.