RESEARCHES CONCERNING THE WATER QUALITY OF FISH FARM CÂRJA 1

Daniela Cristina Ibănescu, Adina Popescu

Abstract
    To obtain big fish productions, one of the most important factors is the quality of water.
    The aquatic environment is under permanent changes due to continuous interaction between biotic and abiotic parameters.
    The purpose of this paper is to analyze the water quality of an aquatic ecosystem anthropogenic (farm Cârja 1) in spring 2011, through biological indicators of the planktonic communities correlated with physical - chemical parameters.
    The determination of water trophicity was based on the functional guilds of phytoplankton communities established by Reynold (2002) Bilous et.al. (2012) by Van Dam et. al, 1994. Also, it was calculated the Saprobic Index on the basis of the qualitative and quantitative identification of the species.
    The Physical - chemical indexes analyzed were: temperature, pH, DO (Dissolved Oxygen), BOD (Biochemical Oxygen Demand) and nutrients.
    The global assessment was made according to the requirements of Order 161/2006. The research conducted on phytoplankton communities led to the establishment of taxonomic structure consisting of 29 species. They belong to five taxonomic groups: Chlorophyceae (42.28%), Bacillarophyceae (17.24%), Euglenophyceae (17.24%), Cyanophyceaea (13.8%), Pyrrophyceae (3.45%).
    After analyzing the biological and physical - chemical indicators, the water farm belongs to Class III - IV water quality which corresponds to meso - eutrophic level.

Key words: phytoplankton, biological and physical - chemical indicators