Evaluation of Land Suitability for Crop Production in Northern Ghana Using GIS and AHP Based Techniques

Abstract

In this study, a land suitability index for crop production in three northern regions of Ghana is spatially generated using a land suitability analysis through the integration of AHP and GIS. The study further exploited actual maize and groundnut yield obtained by farmers in the study area by integrating it with the land suitability index to spatially generate potential maize and ground yield. The actual and potential maize and groundnut yields were overlayed in GIS to produce potential yield losses for maize and groundnuts. Factors of precipitation, slope of land, LULC, soil erosion, OM and the soil type were identified through expert opinion in literature, and assigned weights through AHP for the land suitability analysis. Results obtained from the land suitability index indicates about 19.2 % of land in the three regions is highly suitable for crop production, about 20.8 % is moderately suitable, about 27.0 % is less suitable and about 33 % unsuitable due to settlements and depleted lands. Potential yield loss due to difference in actual and potential maize and groundnuts yields were 70 % and 63 % for maize and groundnuts respectively for the Northern Region, 83 % and 66 % for maize and groundnuts respectively for the North-East Region, and then 66 % and 59 % for maize and groundnuts respectively for the Savannah Region. The AHP and GIS-based land suitability analysis techniques are potentials and effective tools for determining the suitability of land for crop production thereby enhancing sustainable agricultural development through enhancing food security and creation of new jobs.