Conservation Status of Vegetation in the Dryland of Northwestern Nigeria
[1]
Muhammad Nuraddeen Danjuma, Department of Geography, Bayero University Kano, Kano, Nigeria.
[2]
Sa’adu Mafara Abubakar, Department of Preliminary Studies, Abdu Gusau Polytechnic, Talata Mafara, Zamfara, Nigeria.
Vegetation contributes to human and ecosystem existence is overwhelming. It provides food, raw materials and oxygen, as well as in exchange of water, energy, and nutrients. The study assessed conservation status of fifty plant species that were encountered in nineteen study locations in the dryland of northwestern Nigeria. Quantitative data for the assessment was obtained through quadrat sampling. The sampling was done at 100 x 100m2 quadrat in nineteen locations identified on a line drawn diagonally along a north–south transect; which cover the major bioclimatic gradient of the study area. Relative densities of plants are used to categorise the fifty plants into five conservation statuses namely critically endangered, endangered, vulnerable, threatened and stable categories as found in IUCN Red lists version 3.1. Result show that the stable group (6%) consists of Piliostigma reticulatum (RD=21.02%), Guiera senegalensis (RD=12.40%) and Azadirachta indica (RD=10.32%) in order of decreasing relative densities. Vulnerable category (8%) consists of Fadherbia albida (RD=9.79%), Ziziphus mauritania (RD=8.16%), in decreasing order of relative densities. Threatened group (24%) consist of fourteen species. Notable species are Balanite aegyptiaca (RD=4.26%), Adansonia digitata (RD=2.47%), Lannea acida (RD=2.00%) and Acacia seyal (RD=1.60%) in decreasing order of relative density. Endangered group (44%) consist of twenty two species. Notable members are Vitex doniana (RD=0.14%), Anogiessus leocarpus (RD=0.19%), Tamarindus indica (0.38%) in order of decreasing relative density. Critically endangered group (18%) with nine plants comprises of Albizia chivalieri (RD=0.01%), Butyresopermum parkii (RD=0.09%), Proposis africana (RD=0.09%), and Ficus iteophylla (RD=0.09%) among others. The study concludes that there are lot of species in vulnerable, endangered and threatened categories. The study recommends that conservation status assessments and monitoring should be conducted regularly using local parameters so as to provide up to date information for the effective management of vegetation in the country and particularly the dryland of northern Nigeria.
Conservation Status, Vegetation, Dryland, Northwestern Nigeria
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