ALGAE AS BIOINDICATORS FOR WATER POLLUTION IN THE AL-SORA - AL-SOFIA DRAINAGE CANAL AND ITS EFFECT ON EUPHRATES RIVER - AL-KALDIA

Abstract

The present study aims to use algae ( Phytoplankton ) as bioindicators for the Evaluation of degree of pollution in the Al-sora Al-Sofia drainage canal and in Euphrates river from Al-Kaldia pre and post its confluence with drainage canal.Spatial variations of the major environmental factors effected phytoplankton Population dynamics were studied at 3 sites in drainage canal and 2 sites in Euphrates river in monthly basis from Nov. 2010 to Apr. 2011 . Result revealed that drainage canal is polluted according to high values of biological oxygen demand ( BOD ) with low level of dissolved oxygen , and high values of electrical conductivity , Total hardness , Total alkalinity , Sulphate and reactive phosphate values than Euphrates river . Four biological indices of pollution like Saprobic index( S.I ) , Pollution tolerance index ( P.T.I ) , Algal genus pollution index ( A.G.P.I ) and Shannon weaver - diversity index ( H ) , were adopted to classify the water quality of drainage canal and Euphrates river in comparison with the measured physical – chemical water quality . The result shows that the Shannon weaver – diversity index appear to be much more applicable for the classification of water quality of drainage canal and Euphrates river than Saprobic index , Pollution tolerance index and Algal genus pollution index . A total of ( 73 species ) of algae ( Phytoplankton ) were recorded . The diatoms were dominant ( 47 ) . The second dominating group was Cyanophyta ( 14 ) followed by Chlorophyta ( 4 ) Pyrrophyta ( 4 ) Euglenophyta ( 3 ) and then by Cryptophyta ( 1 ) . The result also indicated that following species were the dominant : Nitzschia dissipata , N. palea , Oscillatoria lacostris and O. tenuis .