Land suitability assessment for mango production in Kitui County, Kenya

Abstract

Mango remains an important tropical and sub-tropical crop, ranking as the sixth most cultivated and popular across the globe. Despite thriving in many tropical and sub-tropical areas, regions previously dedicated to mango cultivation are undergoing a shift to different agricultural pursuits due to a lack of sustainable mango output. Due to the spatial variability of factors affecting production, not all areas are suitable for mango production in Kenya. This study aims to develop a Geographic Information System(GIS) and Analytical Hierarchy Process (AHP) technique-based approaches for land suitability assessment for mango growing in Kitui County,Kenya.Thematic maps of all variables (Rainfall, temperature, soils, slope, rivers, land use/land cover, and roads) affecting mango growing were developed using GIS. The maps were evaluated in accordance with the published ideal parameter value ranges for mango production and these evaluations served as a basis for allocating weights to the thematic layers with respect to mango production. Thereafter,the weighted overlay maps of the thematic layers (ArcGIS) were used to develop the land suitability map. The map was categorized into four classes based on mango production suitability namely: highly suitable, moderately suitable, marginally suitable, and not suitable. Results show that 79.8 % of the study area is highly suitable for mango production, 1.1 % moderately suitable, 13.9 % marginally suitable, and 5.2 % is not suitable for mango production. This suggests that a significant portion of the study region is favorable for mango cultivation, with limited sections in the study area that are only moderately or completely unsuited for mango cultivation. The socio-economic factors highly ranked by farmers to be useful for mango production are roads. These results provide useful insights to policy makers, enabling them make informed decisions on how to decrease land degradation and to assess sustainable land use, especially for mango production. Key Words: Land, suitability, assessment, mango, GIS, Analytical Hierarchy Process (AHP), Kenya