COMPOSITION AND RELATIVE ABUNDANCE OF PLANKTONS ACROSS THE NAFADA CORRIDOR OF RIVER GONGOLA, GOMBE STATE NIGERIA

Résumé

Planktonic composition and distribution across the Almakashi corridor of river Gongola, Gombe state was studied for eighteen months (January, 2020 to June, 2021). Plankton samples were collected in the morning before 9.00am once in a month for a period of eighteen months using 20µm mesh size net and transferred into two 250ml well labelled plastic containers with screw cap and stored with 5% formalin in the laboratory for analysis. Data collected was analyzed using descriptive statistics. Phytoplankton composition and diversity indicated 142 individuals and a total of 14 species comprising of four taxa namely; Chloropyceacae, Cyanophyceae, Baccilariophyceae and Desmidaceae. The taxon; Chlorophyceae had the highest value (74), while the least value (3) was recorded in Desmidacae. Analysis on individual species indicated that Spirogyra spp of the family Chlorophyceae had the highest value (28), while least value (3) was recorded from both Pediastrum spp of the family Chlorophyceae and Closterum spp of the family Desmidiacea. Zooplankton composition and diversity indicated a total of 48 individual and a total of 8 species comprising of 3 taxa namely; Protozoa, Rotifers and Copepoda. The taxon; Protozoa had the highest value (25). while the least value (9) was observed in Copepoda. Individual species analysis shows that Rotaria spp of the family Rotifers had the highest value (9), while least value (4) was recorded from both Phacus spp of the family Protozoa and Daphnia spp of the family Copepoda. Phytoplankton family and species were more divers in terms of abundance and distribution within the Almakashi corridor of river Gongola than zooplankton. The abundance high abundance of Spirogyra spp might be that, bloom episodes occurred during the time of the day.