Preliminary census of zooplanktons and phytoplanktons community of Ajeko stream, Iyale, North Central Nigeria

Abstract

The zooplankton and phytoplankton community of Ajeko Stream, North Central Nigeria were assessed between October and December 2010. Prior to sampling, Temperature, Transparency, Dissolve Oxygen and pH were evaluated. Zooplankton and phytoplanktons were sampled using plankton net of 20μm diameter with a collecting bottle attached at the base. Water samples were collected between 8 and 9am every forth nightly from three different points on the stream namely the Lower Course, Middle Course and Upper Course and labeled Stations A, B and C, respectively. Water samples obtained were brought to the Biological Sciences Laboratory of the Kogi State University Ayingba in sampling bottles for analysis of zooplanktons and phytoplanktons. 4% of formalin was used for preservation of zooplanktons and phytoplanktons. Each sample was concentrated to 250ml volume of water using pipette. 10ml was put to Petri-disc and the 1ml was quickly drawn with a wide-bore dropper. Samples were then introduced carefully into the counting chamber with a cover slip and observed under light microscope. The result revealed that zooplanktons were made up of Rotifera (44%), Cladocera (23%), Copepoda (20%) and Protozoa (13%) respectively. Phytoplanktons were made up of Chlorophyta (79%), Bacillariophyta (17%), Euglenophyta (2.54%) and Cryptophyta (2.00%) respectively. The status of the stream could said to be eutrophic as indicated by the diversity of zooplankton and phytoplanktons.

Keywords: Zooplankton, Phytoplankton, Temperature, Transparency, Dissolve oxygen

Animal Research International (2012) 9(3): 1638 – 1644