This study was aimed at investigating the macrophytes composition and species diversity of Rivers Osun and Elemi, located at Ikere and Ado- Ekiti, respectively. Macrophyte samples were collected from both rivers between between the months of May to October, 2023. Nineteen (19) species of macrophytes were collected from each of the two rivers. Osun River had a total number of 730 macrophytes with a percentage relative abundance of 48% while Elemi River had a total number of 794 macrophytes with a percentage relative abundance of 52%. In River Osun, Solenastemon monostachyus was the most abundant (145) and had the highest percentage relative abundance of 19.86% while Coix larcryma-jobi was the least abundant (8) species with a percentage relative abundance of 1.01%. In Elemi River, Alternanthera brasiliana was the most abundant (212) macrophytes species with a percentage abundance of 26.70% while Lepistemon owarianse was the least abundant (7) species with a percentage relative abundance of 0.88%. The diversity indices showed that macrophytes at River Elemi had the highest diversity index (H’= 3.48) and species richness (d = 2.73). It was also noted that macrophyte at River Elemi had the highest evenness index (E’= 1.18). This study also revealed that macrophytes at River Osun had the highest Menhinick index (MH = 0.70) and Simpson index (1-D = 0.91). The dominant macrophytes in both study areas are pollution tolerant species, and the rivers had been impacted by nutrient enrichment.
Key words: Diversity, Abundance, Macrophytes, River Elemi, River Osun.