SOIL PROPERTIES AND FERTILITY POTENTIALS FOR ARABLE CROP PRODUCTION IN THE DRYLANDS OF NORTHERN NIGERIA

This study examined soil fertility potentials for arable crop production in parts of Northern Guinea and Sudan savanna agroecological zones of Nigeria for optimal land use. Five physiographic units were identified in four (4) local government areas each of Kano and Kaduna states and named based on the landforms characteristics as low land plains (LLP), undulating plains with group hills (UPH), gently undulating sandy plains (GUSP), extensive sandy plains (ESP) and upland plains (UP). In each of the physiographic units, fifteen surface (0 – 15cm) and subsurface (15 - 30cm) soil samples were systematically collected and analyzed for soil physical and chemical parameters essential for arable crop production. Also, a representative soil profile was opened in each unit. The results showed that the soil pH values were within the optimal ranges required for arable crop production (5.5 – 7.0). Soil fertility parameters such as organic carbon, total nitrogen, electrical conductivity, ECEC and exchangeable bases were low in the soils except available P. The results also revealed that the values of exchangeable sodium percentage (ESP) in all the five soil units were below the critical limit for sodicity. However, better ways of fertility management such as addition of organic matter and post-harvest incorporation of plant residues into the soil is highly recommended.