ASSESSMENT OF SOIL FERTILITY STATUS AND LAND SUITABILITY FOR MAIZE AND SORGHUM PRODUCTION IN UKUM LOCAL GOVERNMENT AREA, BENUE STATE

This study assessed the soil fertility status and land suitability for maize (Zea mays) and sorghum (Sorghum bicolor (L.) Moench) production in Ukum Local Government Area of Benue State, Nigeria. The study was carried out at four locations: Zaki-Biam, Gbeji, Afia and Gbagir. Soil samples were collected at depths of 0-15 cm and 15-30 cm using a simple randomized sampling system. The samples were analysed for physical and chemical properties including particle size distribution, soil pH, organic carbon, organic matter, total nitrogen, available phosphorus, exchangeable bases, exchangeable acidity, and cation exchange capacity (CEC). Results revealed that the soils of the study area are predominantly sandy in texture, with textural classes ranging from loamy sand to sandy loam. Soil pH ranged from 6.60 to 6.73, indicating slightly acidic to neutral conditions. Organic carbon and organic matter contents were categorized as low to medium, while total nitrogen levels were medium to high in surface soils but decreased with depth. Exchangeable bases showed that the exchange complex was predominantly saturated with Ca2+ followed by Mg2+, Na+, and K+. CEC values fell within the low range according to established guidelines. Soil degradation assessment indicated that all locations were very highly degraded with respect to nitrogen, available phosphorus, and base saturation, while CEC was highly degraded across all sites. Potassium was the only parameter rated as non-slightly degraded. Land suitability evaluation using the method of Sys (1985) classified the soils into suitability classes S1, S2, S3 and N for both maize and sorghum production. The study recommends the application of organic manure such as cow dung and poultry droppings, as well as synthetic fertilizers in appropriate proportions, to improve the fertility status of the degraded soils. Additionally, good agronomic practices such as crop rotation with legumes, fallow, and mulching are recommended to enhance soil fertility and ensure sustainable crop production in the study area.