GEOSPATIAL ANALYSES OF LAND DEGRADATION SITES

(A CASE STUDY OF JOS SOUTH LOCAL GOVERNMENT AREA, PLATEAU STATE, NIGERIA)

By

Author

Presented To

Department of Environmental Design

ABSTRACT
This research work used Geospatial techniques in the analyses of mine-induced land degraded areas of the Jos South LGA of Plateau State. Thus, the objectives were to establish the geometrical characteristics of land degraded sites; determine the attributes of the degraded sites; determine how the degraded areas relate to the neighbouring land use and analyse topography in the neighbourhood of the degraded sites. As an introduction, the concept of mining and land degradation and how the mining caused the land degradation were explanined; statement of the problem identified major issues such as accurate delineation of the degraded sites, the usefulness of the degraded sites, the nature of the terrain in relation to the degradation. The study analysed land degraded sites using multi-sensor satellite imageries of Landsat 8 (2016), SPOT 5 (2012), Quickbird-2 (2010) and SRTM DEM data of the study area. Onscreen digitization of the land degraded areas was carried out using Quickbird-2 satellite imagery; this is followed by Maximum Likelihood Supervised classifications of land cover and land degradation features using fused Landsat 8 and SPOT 5 imageries, this was to determine the area of land that had been affected by mine?induced activities; six land cover classes related to degradation were adopted. Finally, detailed terrain analyses such as slope, aspect, flow direction, flow accumulation, of the study area were carried out using DEM data. The results of the onscreen digitization produced 235 sites with a total area of 11.58km² covering 2.26 % of the study area. Getis-Ord GI* statistics was used to identify Hot or Cold Clusters of the degraded sites from the 235 sites, in which 10 major hot spot sites of 2.02km², at 17.43% were chosen for detailed analyses. Furthermore, all the digitized degraded sites were classified into 13 classes based on their usage. The land use classification had an overall map and Kappa coefficient accuracies of 77.82% and 73.16% vii respectively. The classification results revealed a total land cover of 512.10km2, mine ponds occupying 10.01km2. Terrain analyses revealed that the spatial location of the degraded sites is irrespective of the terrain because most of the degraded sites occurred because of mining activities; which can be done whether at high or low land. Moreover, the terrain of the study area has continuously been altered and remodified by mining activities and unplanned mine wastes resulting to the present degraded sites. The research has adequately addressed issues of the economic value and consequences of the degraded sites and relationship between terrain and degradation. Three-way approach: onscreen digitization, automatic classification, and terrain analyses have been explained which had not been done in previous researches. Lastly, it is recommended that, certain appropriate LULC in the neighbourhood could be utilized productively; block industries, water treatment plants, fish farming, etc, should be sited around the seasonally inundated mine pond; implementation and enforcement of the existing mining laws at all levels to safeguard the environment and ecological funds being provided by the Federal Government should be utilised.