Land Suitability Evaluation for Maize Production and Taxonomic Classification of Soils Overlying Undifferentiated Basement Complex in Northeast Nigeria

Soil characterization, classification and evaluation provide useful information for the understanding of its different facets, hence their potentials and limitations for crop production. Such information is lacking in the general area of Kona-Jalingo in Taraba State, Nigeria, hence the study to determine the macro-morphological, physical and chemical properties of the soils; classify them up to the subgroup level using USDA, and correlate them with WRB/FAO Soil Map Legend, and evaluate their suitability for maize production. Topographic units: crest, upper, middle and lower slope were identified through a free soil survey technique. Soil samples were collected and analysed using standard laboratory procedures to determine the morpho-physicochemical properties; In contrast, the direct method of land evaluation was used to ascertain the suitability of the soils for maize production. Results revealed that soil consistency ranged from sticky to plastic (wet); very friable to the firm (moist), and soft to hard (dry). The soils composed of blocky structures with the presence of mottles across the pedons except in the surface soils and sub-soils of KCP1, KUSP1 and KUSP2. Texturally, the soils were loamy sand and sandy loam. Soil depth ranged from 125cm – 200 cm; soil colour ranged from dark greyish brown to brown. Mean bulk density and total porosity value was 1.62g/cm3 and 40.19 %, respectively. Soil pH varied from 4.3 to 7.3, while soil organic matter, total nitrogen, available phosphorus, percentage base saturation, and CEC were generally low. Ochric epipedon was observed in all pedons designated as KCP1, KUSP1, KUSP2 and KMSP2 and these belonged to the order Ultisol; KCP2 and KMSP1 fell under Inceptisol, while KLSP1 and KLSP2 were Entisol. When soil characteristics were matched with land use requirements for cultivation of maize, the results showed that the soils in the study area were marginally suitable for maize cultivation, perhaps due to low nutrient status. Adequate incorporation of organic manure; cropping across the slope to minimize nutrient loss by run-off water; embarking on afforestation program to serve as a windbreak and reduce wind effects on soil particles, were the recommended management strategies.