Nigeria as a microcosm of the sub-Saharan Africa has agriculture as her mainstay which provides employment and source of livelihood for the increasing population. Sesame also known as beniseed, which is a very sensitive cash-crop to environmental factors such as rainfall, temperature and soil types; is not an exception as it has become one of the foreign exchange earners for Nigeria. The objective of this project is to use Geographical Information Systems (GIS) as a decision making tools to solving the spatial problems of sesame suitability mapping in Nigeria. Basic GIS operations ranging from spatial to aspatial search, reclassification and overlay were performed on the digitized Nigerian maps showing rainfall, temperature and soil types; having been converted from their respective analogue forms to digital forms. Consequently, these digitized maps were manipulated having been "rubber-sheeted" with a Nigerian administrative map of known coordinates, using the Arcview 3.2a software. The basic GIS operations revealed a cartographic model that showed the structural relationship which resulted when the themes/layers of the maps were overlaid. The resultant effect was a selection of some of the states in northern Nigeria owing to the criteria adopted for this research project. Therefore, adopting other criteria favoring the suitability mapping of sesame cultivation in Nigeria could result to other areas when sesame is also cultivated. This is the beauty of Geographical Information Systems (GIS), whose bed rock is that of efficient manipulation.
- reclassification and overlay,
- rubber-sheeted etc
Available at: http://works.bepress.com/charles_alegbe/1/