ABSTRACT
The abundance and diversity of plankton in relation to the physico-chemical parameters of River Ethiope was investigated over nine stations of the river to determine the extent of water quality for fish production. Plankton abundance data from the study stations show that phytoplankton were more in number than zooplankton. During the rainy and dry seasons, phytoplankton species of the Phylum Chlorophyta comprising Chlamydomonas, Cladophora, Pediastrum, Selenastrum, Spirogyra, Ulothrix and Volvox dominated the phytoplankton population with 40.63% and 47.18% seasonal abundance respectively. Zooplankton of the Phylum Arthropoda was more abundant in the rainy (28.01%) and dry (32.73%) seasons respectively. Plankton species diversity indices show that phytoplankton were richer in the dry season than in the rainy season with higher values in Station I in both seasons while zooplankton were richer in Stations IV and VI in the rainy and dry seasons respectively. However, values were not significantly different (P>0.05) among the stations. A significant (P<0.05) negative correlation was observed for phytoplankton with calcium, and with depth during the rains. Magnesium correlated positively with zooplankton (P<0.05) also during the rains. No significant (P>0.05) correlation was recorded between plankton and physico-chemical parameters during the dry periods. The study findings indicate that plankton abundance and diversity were influenced by seasonal changes in the physico-chemical parameters of Ethiope River. The findings also provide other vital information suggesting that plankton abundance and diversity may be used as indices of water quality assessment for increased fish production. |
KEYWORDS: |
Plankton, abundance, diversity, physico-chemical parameters, Ethiope River. |
