| ABSTRACT | Volume 1, Issue 5, Pages 177-185 (July 2015)

Research article SPATIO-TEMPORAL VARIATIONS OF PHYTOPLANKTON COMMUNITY OF THE DOUGLAS CREEK, QUA IBOE RIVER ESTUARY, NIGERIA | Lawrence Etim | Mfon Udo | and | Ofonmbuk Obot |. The American Journal of Innovative Research and Applied Sciences. 2015; 1(5)177-185. |PDF FULL TEXT|

ABSTRACT Background: The phytoplankton in Douglas creek, Qua Iboe River estuary, Nigeria, was studied for two years. Objective: The study was carried out to provide information on the phytoplankton communities of Douglas creek, inter alia, status, spatial and temporal variations in their distribution, abundance and the ecological implications. Methods: Monthly samples were collected from three stations using a plankton net and preserved in 4% formalin. This was stored in a cool box and taken to the laboratory. The samples were allowed to stand for at least 24 hours for the phytoplankton to settle before the supernatant pipetted to concentrate the samples. Few drops of the concentrate were investigated at different magnifications under a Zeis inverted microscope. Appropriate texts were used for identification of the phytoplankton species. Rainfall data was collected from Meteorological Unit, Department of Geography, University of Uyo, Nigeria. Results: A total of fifty-eight species belonging to six taxonomic groups were obtained. Cyanophyta was the most abundant (70.42 %) of the total composition by number. It was dominant in twenty of the twenty-four months studied. Bacillariophyta had the highest number of species (29) and represented 50 % of the total composition by species. This was followed by Chlorophyta, representing 2.36 % of the total composition by number with 6 species. Dinophyta represented 1.22 % of the total composition by number while Euglenophyta and Xanthophyta both recorded 0.23 % each of the total recorded composition by number. All the phytoplankton taxa were more in the wet season except for Euglenophyta. Cyanophyta and Dinophyta showed significant seasonal variations (p<0.05). Margalef’s Species Diversity, Shannon-wiener’s index and species composition decreased downstream. Conclusion: High abundance of certain Cyanophyta taxa suggested environmental degradation, thus the biological integrity of the Douglas environs may soon be compromised, if pragmatic, periodic, ecological surveillance and mitigation measures are not adopted by government and concerned organized private sectors. Key word: Phytoplankton, Douglas creek, Pollution.