FLORISTIC COMPOSITION AND STRUCTURE OF TWO PROTECTED AREAS IN OGBA ZOO AND NATURE PARK, BENIN-CITY, EDO STATE

ABSTRACT Ogba Zoo and Nature Park, located in Benin City, Edo State, Nigeria is one of the foremost and likely the urban forest reserve in mid-western Nigeria. The design outlay of this facility consist a web of thoroughfares trails interspersed by undisturbed protected areas in rectangular plots. This study evaluates the floristic composition and structure of the two protected areas, designated Plot A and B, and measuring 78.1 m x 35.25 m and 78.1 m x 15.75 m respectively. Bi-weekly visual surveillance of the area was used to determine species composition, while vegetation density of diversity assessment were evaluated using quadrat measuring 14m x 12m in three replicates. A total of 38 plant species belonging to 37 genera in 22 families were recorded out of which Fabaceae (33.33%), Euphorbiaceae (19.05%) and Rubiaceae (14.28%) were the most represented. Among the growth forms, trees accounted for 57.89%, followed by shrubs 21.10%, herbs 10.53%, and liana 5.26%. The phytogeographic profile showed that native plants were more abundant accounting for 97.4% of the total plant species identified, while only 2.6% were of exotic origin. Shannon-Wiener and Simpson's indices indicated richer species composition and higher diversity in Plot A (3.068 and 0.9394) than Plot B (2.795 and 0.9267). Plant distribution based on primary uses showed that medicinal plants were the most represented with 14 species, timbers 13 species, ornamentals 4 species, fruits and essential oils and exudates 2 plant species each, and vegetable oils 1 species. The conservation status of the plants showed that protected Plot A contained vulnerable plant species such as Anopyxis klaineana and Terminalia ivorensis, while Plot B contained a least concerned species, Chassalia kolly. This implies that protected Plot A requires more stringent fortification and interest for the preservation of vulnerable species. The results from this study show that protected areas are capable of preserving the biodiversity on such areas.