Land capability evaluation and classification of Obosi Land in Anambra State Nigeria

Abstract

Land capability evaluation and classification of Obosi land was carried out on an approximately total area of 25.58km2 using the map of the area. The aims of the study were to map out the soils of Obosi, classify them for suitability and sustainability for agricultural production and other land use development projects. Auger sample and profile pit samples were collected and examined. Using morphology and topography of the surveyed area, three mapping units; MUI-lowland areas, MUII- upland areas and MUIII-gullied areas were established. The result of the study indicated the textural class of the soils to be sandy loam, except for upland areas in Auger 1 were the textural class were loamy sand. The particle sizes range from 50gkg-1-90gkg-1 clay, 50-90gkg-1 silt, 130-590gkg-1 fine sand and 310-650gkg-1 sand. The pH of the soils varies from slightly acidity to slightly alkaline and was fairly uniform throughout the depths. The exchangeable bases, CEC, TEA, SAR and ESP of the soils were found to be low and below their critical level for crop production the base saturation value of the soils range from 22.28-99.21%. The low land areas and the upland areas were found to be suitable for arable crops. They fall under the suitability class S2 (suitable) and the capability class 11. Their major constraint on agricultural production is low fertility status. The gullied areas MUIII were found within the uplands and low-land areas. They fall under the non-suitability class NS (not suitable) and the capability class vi. The prominent limitation of this unit is erosion hazard. The area cannot be used in their present state without serious reclamation activities. The soils were classified as mixed isothermic kandic argiudult using the USDA soil Taxonomy and correlated as eutric ferralsols by FAO-WAB classification. Generally the soils need to be upgraded in soil nutrients through soil organic matter application and reclamation processes to produce maximally.