Influence of Environmental Pollution on Soil Types and Properties in The Niger Delta Area of Akwa Ibom State, Nigeria

A field soil survey and laboratory studies were carried out to examine the influence of crude oil and industrial wastes pollution on soil profile development and characteristics in Ikot Abasi, Niger Delta area of Akwa Ibom State, Nigeria. Nine soil profiles, three each, in oil affected site (OAS), industrial waste affected site (IWAS) and non-contaminated (control) site (NCS), respectively, were studied. Soil samples were collected and analyzed in the laboratory for some physical and chemical properties. The result of soil classification following the USDA Soil Taxonomy and correlated with the World Reference Base for Soil Resources (WRB) showed that all the three pedons from the control (NCS) were highly weathered and matured soils (Ultisols). Of the three pedons from the OAS, two (66.7%) were matured while one (33.3%) was young soil (Inceptisol/Cambisol). Similarly, of the three pedons from the IWAS, one (33.3%) was matured (Ultisols/Acrisols) while two pedons (66.7%) were young soils (Inceptisols/Cambisols). This indicates that environmental pollution can retard soil formation and profile development resulting in relatively young soils. Furthermore, analysis of variance (ANOVA), showed that soils of OAS were significantly (P< 0.05) different from those of IWAS and NCS in 12(52.2%) and seven (30.4%), respectively, of the 23 soil properties considered. Also, soils of IWAS were significantly different from those of the NCS in six (26.1%) of the soil properties. The result further showed that oil pollution significantly increased soil total hydrocarbon (THC) and lead (Pb) contents as well as organic matter content (OM), available phosphorous (P) exchangeable potassium (K), micronutrients (Fe, Zn, Cu, Mn) and lowered exchangeable acidity (EA). Industrial wastes also increased soil exchangeable calcium (Ca) and K and effective cation exchange capacity (ECEC) and lowered EA. Therefore, appropriate remediation and land management practices can ameliorate the harmful effects of these pollution activities while the essential nutrients and positive influences imparted to the soil during the pollution are harnessed to improve the land/soil qualities and characteristics.