As agricultural land in the Niger Delta area is dwindling due to inherent lack of dry and relatively well drained land and increase in population and competition from land for urbanization and industrialization, the need to monitor and manage the limited available land for agriculture becomes very paramount. This study seeks to evaluate the variability of properties of Koroama (KRM) and Niger Delta University (NDU) farm soils on the Nun River plain and the implications for soil management. Soils varied morphologically, including soil colour, mottling and sequential arrangement of horizons within and between physiographic units and between the two locations, KRM1 showing evidence of anthropogenic influence. pH was the least variable characteristics while organic C, total N and available P were highly variable (CV= ≥35) in all the physiographic units. Calcium dominated the exchange complexes of the two locations, showing varying degree of variability while Mg and K were highly variable (CV= ≥35) in all physiographic units of Koroama. Exchangeable Al, acidity, TEB and CEC exhibited varying degree of variability in the different physiographic units of the two locations, reflecting differences in the source of parent materials and possibly, the degree of hydromorphism. The variability in morphological, physical and chemical characteristics reflected the effects of flooding, source of parent materials and the degree of hydromorphism, all of which dictated the pedo-chemical environment and should be considered in managing the soils.
Keywords: Flooding, Niger-Delta, hydromorphism, variability
