Vol. 3, Issue 1, Part A (2021)

The research was carried out on the floral composition of Neni-Nimo watershed between November 2019 and July 2020. The research work aimed to find out the various plant species that inhabit the watershed, their abundance measures and importance values. In this study, the watershed was divided into three catchment areas, the upper, the middle and the lower catchment. Each of the catchment zones was divided into component parts, with an area of (50 m X 30 m) each. The experiment was laid in a randomized complete block design. A plotless sample technique called the centre point technique was used to ascertain importance values Indices (IVI) for trees, while the plot count sampling technique (quadrant) was employed for shrubs, forbs, grasses and climbers. Random sampling techniques were employed in all cases to eliminate bias. The encountered growth forms such as trees, shrubs, forbs, climbers and grasses were identified and recorded. The important values index (IVI) was obtained for all the growth forms. The encountered species were quantitatively analyzed for density, frequency and abundance or dominance depending on their various growth forms. The importance value indices for each of the species were determined by summing up relative density, relative frequency and relative abundance of the species. The result shows that trees were the most abundant flora in the upper catchment area with Elaeis guinensis being the most dominant species. At the middle catchment, shrubs were the most abundant flora, with Chromolaena odorata being the most dominant species. Also at the lower catchment area, shrubs were the most abundant flora, followed by grasses. Venonia amygdalina had the highest abundance for shrubs while Zea mays had the most abundance value for grasses at the lower catchment. The study revealed that most of the dominant species in the three catchment areas were crops of economic value which are planted by man.