PRELIMINARY ASPECTS CONCERNING ZOOPLANKTON STRUCTURE IN ECOSYSTEMS OF THE FISH FARMS

摘要

This paper presents information about the structure and dynamics of zooplankton during vegetative season in three Romanian cyprinids production farms. The technical differences among the studied fish farms are represented by the source of ponds water supply and the size of the ponds. To establish the structure and the dynamics of the zooplankton, there were collected two sets of biological samples, at the beginning and at the end of vegetative season. The zooplankton was analysed from a qualitative (identification, until species level, of organisms from each systematic group) and quantitative (the numerical density, the numerical abundance and biomass) point of view. The zooplankton was representative in all sampling stations during the entire vegetative season. The small number of species evidences a reduced biodiversity of animal plankton during the studied period.