The epipelic algal distribution of upper bonny estuary, Amadi-Ama creek, Niger delta in relation to sediment quality indices

The epipelic algal distribution in Amadi-Ama creek with respect to the sediment parameters were investigated from January 2009-December 2010(2years).Epipelic algal and sediment samples were collected from six sampling stations and analysed following standard limnological method of APHA. A total of 9709count/ml and 9584count/ml epipelic algae consisting of five(5) taxa and 79 species were identified in 2009 and 2010 respectively(Table1).Epipelic algal abundance followed the order: Bacillariophyceae > Cyanophyceae > Chlorophyceae > Euglenophyceae > Chrysophyceae. Spatially, the highest abundance of epipelic algae was recorded in station 3 in 2009 (2189count/ml) and 2010 (2262count/ml) representing 22.55% and 22.96% respectively. The most dominant species of epipelic algae observed was Cyclotella operculata. Apart from temperature, other sediment parameters such as pH, conductivity, nitrate, sulphate, phosphate and chlorophyll‘a’ exhibited spatial difference significantly (p < 0.05). The high phosphate levels above the USEPA permissible limit in natural aquatic bodies indicate organic pollution. The observed chlorophyll‘a’ level in this study placed Amadi-Ama creek between mesotrophic and euthrophic level of productivity.