A Floristic Assessment of Woody Plant Diversity in Secondary Forest, Ile-Ife Nigeria: A Proactive Step to Monitoring the Diversity Loss and Degradation

Abstract

Loss of biodiversity has been recognized as one of the main threats to the forest ecosystem. This study examined the diversity and conservation status of woody species in the secondary forest of Obafemi Awolowo University, Ile-Ife, Nigeria using six permanent plots. All woody species were completely enumerated, and identified; their girths at breast height were measured at 1.3 m above buttress. Biodiversity status was assessed using Shannon-Wiener diversity, evenness of distribution, Sorrenson index of similarity and species importance value index. There were 77 tree species distributed into 62 genera and 30 families. The most abundant species were Celtis zenkeri and Lecaniodiscus cupanioides, while the most abundant families were Moraceae, Euphorbiaceae, and Fabaceae. The tree species density ranged from 508 – 1132 plants per hectare. The Shannon-Weiner diversity index (1.83 to 3.50), evenness (0.483 – 0.741) and the basal area (6.06 – 25.73 m2 ha-1) were high in the forest. However, Celtis mildbraedii is critically endangered, while Garcina kola, Mallotus oppositifolus and Ricinodendron heudelotii are vulnerable. This study provides baseline diversity data for the conservation of woody species in the forest and concludes that this secondary forest is a potential biodiversity hub if properly managed. It will also play a key role in fashioning out realistic, appropriate, and effective conservation strategies that will enhance the restoration and management of the floristic composition of the secondary forest.

Keywords

• biodiversity;
• conservation;
• endangered;
• secondary forest;
• woody species