GEOSPATIAL ANALYSIS OF WETLANDS DEGRADATION IN MAKURDI, NIGERIA

Abstract. Globally, the amount of wetlands have being on the decline due to the fragile nature of these ecosystems and unplanned land consumption practices. This has created pressure on suitable land for cultivation in most developing countries where most of the growing food demand originates. Previous studies revealed that wetlands and agricultural landuse dominated the landscape of Makurdi. However, the trend is changing in recent times. Makurdi has undergone tremendous transformation in its landuse/landcover due to rapid urbanization since 1976 when it became the capital city of Benue State. To estimate the land cover change in Makurdi, Landsat ETM, ETM+ and OLI satellite data for 1996, 2006 and 2016, respectively were utilised. The study adapted the Kappa index for assessing accuracy of the land use/cover maps generated from the analysis to improve the accuracy of results. An accuracy level of 80 to 91 % was achieved. The results reveal an overall significant increase in built-up area and other land uses at the expense of wetlands from 26.3 % in 1996 to 18.1 % in 2016. Further analysis includes the land consumption rate (LCR) and land absorption coefficient (LAC) which reveals the role of population expansion in the recorded levels of wetland losses recorded in this study. The study projects a further decline of wetland cover by 33.15 km² (or by 22.57 %) in 2026 if steps are not instituted to control the rate of decline. Suggestions are made to align with and incorporate into policy the strategic need to adopt the provisions of the SDGs at local levels if we intend to avert the massive failure recorded by the now rested MDGs.