Floral diversity in the wetlands of Ibeju-Lekki Area, Lagos, Nigeria

Abstract

Until very recently poor attention has been given to the management of wetlands in Nigeria despite their significance in the global food and water supply, energy needs and disaster management. Due to the rapid development of the Lagos coastal areas for commerce and industrial purposes, the natural coastal vegetation made up of various wetlands are destroyed daily. In ten years' time, much of these wetlands would have given way to industrial structures and the biodiversity will be difficult to reconstruct. Therefore, to document the taxa of these wetlands and show the importance of the wetlands of Lekki, Lagos Nigeria, a vegetation mapping and survey of wetlands in Ibeju-Lekki Area was conducted. Three wetland sites designated A, B and C, proposed to be affected by the new Lekki Port, were mapped and studied within a 5 km radius of the axis, extending from the beach vegetation to the hinterland of the Lekki lagoon. A total of 49 species in 45 genera belonging to 29 families were identified. Members of the Cyperaceae family, Nymphaea lotus Linn., Raphia hookeri G. Mann et H. Webdl., and Pteridium aquilinum (L.) Kuhn were common in the three sites. Site A has the highest number of species (35), Simpson's, Shannon-Wienners and Margalef index values of 0.9385, 3.057 and 5.225 respectively. The sites with the highest anthropogenic activities indicated the lowest floral diversity (Site B) and abundance of weeds (76.8 %). The high floral diversity found in the undisturbed site (site C) indicates that the wetlands are correlated with their functions in biodiversity and other indirect benefits. Hence, the conservation of these wetlands is encouraged.

Keywords: Lagos; wetlands; biodiversity; anthropogenic activities; weeds; conservation