Analysis of Land Use/Land Cover Transition in Warri Vegetation Zone of the Niger Delta Region Using Geospatial Techniques

Abstract

This study analysed the land-use and land-cover transition of Warri vegetation zone of the Niger Delta Region over the last four decades using Landsat imageries of 1975, 1987 and 2015 with the aid of Remote Sensing (RS) techniques and Geographic Information System (GIS). The study area covered 187 km2 and four land use/land cover types where analysed: Mangrove, non-mangrove, water body, and Urban area. The results show that as at 1975, out of the total area of 187 km2, mangrove-covered 63.28 km2 which was 33.8%, non-mangrove covered 87.01 km2 which was 46.5%, water bodies covered 9.7 km2 which was 5.2% and Urban settlements covered 27.01 km2 which was 14.4%. By 2015, Mangrove covered 37.5 km2 which was 20.1%, non-mangrove covered 45.7 km2 which was 24.4%, water bodies covered 19 km2 which was 10% and Urban settlements covered 84.7km2 which were 45.3%. The results show a rapid and haphazard increase in urban areas, while a reduction in mangrove and non-mangrove vegetation. This is as a result of Urbanization, oil and gas exploration and other anthropogenic activities. Kappa coefficient was used to estimate the accuracy of the classification process and an average of 93% accuracy was recorded for the three years of study. The annual rate of change was calculated and used to project the likely state of land-use and land-cover in Warri metropolis by the year 2030 if current trends and practices are not hindered. The annual rate of change for mangrove was -0.64km2 per annum and Non-mangrove was -1.03 km2 per annum while Urban settlement experienced an increase and an annual rate of change of 1.44 km2 per annum. The rate of vegetation loss over the past four decades and the annual rate of change is of notable concern and the need to implement conservation strategies, urban planning and sustainable development practices is paramount to prevent a complete loss of vegetation sometime in the future.