Characterization, Classification, and Land Use Assessment of Representative Soils in the Isoko North Area, Delta State, Nigeria

Soil assessment of the Isoko North area of Delta State was conducted using morphological, physical, and chemical properties. Twenty (20) disturbed samples were collected at different depths from the genetic horizons of four (4) profiles sunk in four land use types (swamp, forested, oil palm plantation, and arable farmland) in Oto’r Owe, Ozoro, Ofagbe, and Iyede. Soil profiles were described using the USDA 1995 soil description standard. The physical and chemical parameters were analyzed using standard laboratory procedures. Data obtained from the study were analyzed, and the results showed that the texture was generally sandy loam to loamy sand. The pH rating varied from extremely acidic (4.43) to moderately acidic (5.96). Organic carbon contents were low (2.73%–6.87%), and total nitrogen content ranged from 0.14% to 0.34%. The available phosphorus content ranged from 0.62 to 50.28 mg/kg. This study revealed that soil physicochemical properties varied with land use. The ranking of the four transects based on potentials was Iyede> Ozoro> Ofagbe> Otor Owe. Iyede (arable farmland), Ozoro (forest), and Ofagbe (oil palm plantation) are grouped into land capability class II, whereas Otor Owe (swamp land use) is classified as land capability class IV. The study concludes that all the soils belong to two soil orders (inceptisols and mollisols) in USDA soil taxonomy. Continuous cropping, fallowing, mixed cropping, organic manure application, and crop rotation in Iyede (arable farmland) led to an increase in fertility status compared with the other three land uses. Therefore, it is advisable that the farmers and agriculturists within the area adopt these agronomic practices that suit the soil characteristics and encourage the use of soil amendments that will improve the quality of the soil and, in turn, enhance agricultural productivity.