Application of Geographic Information System (GIS) in residential land capability index mapping of a developing country. A case study of Enugu state, southeastern Nigeria

Abstract

It was projected that the population of Enugu State will grow at approximately 300% by the year 2020. This is true considering the 3,237,298 population figure of the area in the year 1991. Accommodation problems and lowering of peoples standard of living are always associated with over population. It therefore, becomes necessary to map out areas
on a sustainable basis and most suitable for the siting of residential buildings to accommodate the teeming population. Land capability index mapping using Geographic Information System (GIS) principles was used for this study. The study was undertaken using Arc View 3.2a academic, Micro soft Excel statistical software and integrated land and water information system software (ILWIS). A total of 12 land use determinants were selected as thematic data layers and basic factors influencing the choice of residential landuse. Soil characteristics and geology were integrated into the thematic maps to facilitate the weighting of the basic determinants. The thematic layers were weighted on a scale of 0%-100% and 0-2 inclusive, using the criteria obtained from field work and laboratory investigation. The thematic layers were subjected to overlay using Arcview software overlay model builder. The operation yielded a layer of preferred residential landuse options in a map form. Three areas of varying suitabilities resulted from this operation, and includes areas suitable for
residential landuse-options, and occupies 10% of the study area. Others are areas of low suitability (60%) and areas unsuitable for residential landuse, which occupies 30%.