Assessment of hydraulic conductivity and soil quality of similar lithology under contrasting landuse and land cover in humid tropical Nigeria

Abstract

The study assessed hydraulic conductivity and soil quality of some tropical soils of Nigeria. Field studies were carried out in eight Local Government Areas of Imo State with contrasting land use and similar lithology (coastal plain sands). These included Owerri west (Bare fallow) Mbaitoli (Industrial Area), Owerri Municipal (Residential Area), Ohaji/Egbema (Cassava Cultivated), Ikeduru (Oil Palm Plantation), Ngor-Okpala (Continuous Cultivated), Aboh–Mbaise (Excavated Site) and Owerri North (Bush Fallow/Control). Top soil samples of 0-20cm were collected from each land use type. Soil sample was also collected in fallow plot as a tool for comparison. Soil samples were air dried and sieved for standard laboratory analysis. Data obtained were subjected to statistical analysis. Results showed nutrient depletion in soils of all land uses compared to the fallow plot. Sand content (812.3g/kg) dominated the texture of all soils studied. All soils studied had slightly acidic soil reaction with mean value of 4.73. With regard to hydraulic conductivity, following the land degradation index (LDI,) high land degradation was observed in the excavated site (-92.9), Residential Area (-87.3) and Industrial Area (-84.1) with corresponding higher bulk densities and lower soil porosity compared to other soils .Generally, soils of the excavated site were highly degraded, followed by the residential area, industrial area, continuous cultivated area, cassava cultivated plot, oil palm plantaion and bare fallow plot, respectively. Dense population, blank utilization of lands, soil mismanagement, deforestation, high temperature and rainfall, intensive cultivation were observed to have aided the decline of soil quality. Adoption of night soil technology as well as other organic and climate smart agricultural practices should be encouraged.