Application of gis-based multi-criteria decision analysis techniques in evaluating soil suitability for cotton cultivation :

Abstract

In this study an attempt was made to analyse the soils of Tororo district, Eastern Uganda for soil suitability evaluation for cotton cultivation using geographic information system (GIS)-based multicriteria decision analysis techniques. The study shows the effective nine parameters (calcium carbonate, organic carbon, soil pH, soil type, coarse fragments, soil texture, slope, drainage and altitude) that were analysed and reclassified by matching the requirements of cotton crop with the properties of a particular land unit into different suitability classes such as; S € {S1, S2, S3, N} = {highly suitable, moderately suitable, marginally suitable, not suitable}. The thematic maps of the factors that determine the potential for cotton cultivation were formed (from the effective nine parameters), overlayed and weighted to come up with a soil suitability map for cotton cultivation. The area analysis revealed that, 28274.7598 ha (23.6332%) was Highly suitable (S1), 50722.5312 ha (42.3960%) was Moderately suitable (S2), 20824.7154 ha (17.4061%) was Marginally suitable (S3), and 19817.9935 ha (16.5647%) was not suitable (N) for cotton cultivation in Tororo district because of uncorrectable factors such as soil depth and slope. The study demonstrated that GIS-based multicriteria overlay analysis of soil thematic parameters will be of immense help in soil-suitability evaluation for cotton.