THE USE OF REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM IN LAND USE MANAGEMENT
ABSTRACT
The purpose of this research is to apply Remote Sensing and GIS in land use management of Greater Karu Urban Area, Nasarawa State. Specific objectives are to; create land use/cover map of the study area from 1972 to 2012, determine the rate and magnitude of change, determine the suitability of the land for different uses and determine the extent of encroachment into the approved setback areas. Landsat MSS, TM, ETM and Spot-5 satellite imagery of 1972, 1987, 2000 and 2012 were used. A supervised classification approach using ILWIS 3.3 version was also used. Six categories of land use/cover types were generated as follow: built up areas, water bodies, agricultural land, vegetation, rock out crops and bare surfaces. Euclidean distance and weighted overlay from spatial analyst tool of ArcGIS 9.3 software was used for the suitability analysis using Multi-Criteria Decision Analysis and Analytical Hierarchical Process. The guidelines in line with Land Use Act Cap 202 of 1990 and the Nigeria Urban and Regional planning Act of 1990 to monitor and control all developments approved setbacks was adopted. Results from the analysis revealed the Increase in built up area resulted to changes in other land use/cover categories between 1972 and 2012 as follow: natural vegetation has drastically decline from 68.9% to 52.9% between 1972 and 1987. It further decline from 34.3% to 25.4% between 1997 and 2012. Agricultural land witnesses an increase from 8.7% to19.1% between 1972 and 1987. Thereafter, decreases from 25.9% to 15.2% between 1997 and 2012. Bare surfaces witness an increase from 7.8% to 9.1% between 1972 and 1987. Further decrease from 12.2% to 11.6% was observed between 1997 and 2012. Rock outcrops increases from 2.9% to 3.0% between 1972 and 1987. Further increase was experienced from 3.0% to 3.1% between 1997 and 2012 Water bodies covers 10.6% in 1972 and decrease to 6.1% 1987 before increasing to 7.7% in 1997 and subsequent decrease by 5.8% in 2012. The most dramatic increase experienced in built-up area is shown from 1990 to 2012, coinciding with the relocation of the FCT from Lagos to Abuja in 1991. This result to haphazard development and encroachment of built up areas into the approved setback of road network and water bodies are as follow: Highway; 2.5468 Sqkm, local distributors: 1.305 Sqkm, access roads/streets; 1.345 Sqkm rivers, 48Sqkm. It thus recommends the Nasarawa State Government and planners to use the final suitability maps for discussions and decision making in development of the area. At the absent of that, the final suitability map is recommended to guide development in the area.
1.1 BACKGROUND TO THE STUDY
Land is the foundation of all forms of human activity. From it humans obtain the food, shelter and the space to work and relax. Land is amongst man‟s most valuable resources. It is a means of life on which our continued existence and progress depends (Dale, Peter and John, 1988). Land is man‟s most valuable resource. It is the means of life without which he could never have existed and on which his continued and progress depend. Land is a term with many meanings
