Abstract
Anthropogenic activities associated with constructions, cultivation and grazing are ongoing in Abubakar Tafawa Balewa University (ATBU), Yelwa campus which may lead to loss in biodiversity and change in the community structure of its vegetation. This study therefore aimed at determining the community structure of herbaceous vegetation within ATBU, Yelwa campus to provide base line data for future conservation of the campus vegetation. The phytosociological study of herbaceous species within ATBU, Yelwa campus was conducted between October, 2019 – February, 2020 using quadrat method. Random sampling was used with a square quadrat of 1m2. Twenty (20) different stands of herbaceous vegetation were sampled. Quantitative parameters, viz: frequency, density, abundance, cover and Importance Value Index (IVI) are determined. Fifty-seven species (57) belonging to 17 families were discovered. The community structure of the entire ATBU, Yelwa campus of herbaceous vegetation revealed Ageratum – Cynodon – Stylosanthes as dominant with IVI values of 20.2, 19.7 and 16.4 respectively. Codominant species were Pennisetum – Gomphrena – Digitaria with IVI values of 16.3, 15.5 and 12.3 respectively while the rare species were Hibiscus – Paspalum – Setaria with IVI values of 0.3 each. The herbaceous community of ATBU, Yelwa campus, Bauchi was found to be heterogenous, based on the frequency class distribution. Shannon Weiner Index delineated a good biodiversity with Hꞌ = 3.296, a species richness of 57 and Evenness = 0.8. The findings of this study showed that invasive species are gradually displacing the native species of the community and thus the need to take necessary conservation measures.

Key words: Phytosociology, Herbaceous species, Importance Value Index, Biodiversity, ATBU herbaceous community.