Distribution of Heavy Metals in Urban Soils; A Case Study of Calabar Area, South-Eastern Nigeria

摘要: This work presents an attempt to establish the degree of anthropogenic influences selected trace metals distribution in soils from Calabar area south-eastern Nigeria. Fe, Mn, Pb, Cu, Zn, Cd, Co, Cr, As and Ni concentrations were determined for different categories within study area. Various geo-statistical other techniques used assessment metal concentration urban soils. Geochemical data show levels be background values geo-accumulation index (I geo) confirms that these are unpolluted - moderately polluted, thereby posing no significant environmental impact. The slightly elevated Pb attributable emissions automobile along motored roads, waste disposal repair shops forms indiscriminate dumping effluents commercial areas. Principal component analyses; correlation, factor cluster analyses indicates dominant lithogenic control subordinate anthropogenesis. Metal speciation reveals elements unsaturated bound immobile phases with some occurring as free mobile ions. mapping have recent times found diverse applications studies environment using various sampling media. has been geared by need identify contaminated land subsequent health risk assessments. Soils considered a very important ecological crossroad landscape because it constitutes recognizable repository transfer, retention domiciliation current or potentially toxic pollutants geo-system. contents potential may natural sources but increases time related anthropogenesis urbanization. Rock weathering often mobilizes into soil leading dispersion geochemical cycle secondary environment. Contents govern composition plants animals attendant influence on human animal health. Trace element depends factors such nature parent material, processes, activity climatic conditions (Martinez et al., 2003). As, Pd, Cd characterized long residual periods, high invisibility, little toxicity complexity behaviours (Alloway, 1995). metals, even most ones can essential