Heavy metal analysis in the soils of in and around Robe town, Bale zone, South Eastern, Ethiopia

Abstract

The purpose of this study was to assess physicochemical parameter and heavy metalconcentration of the soil in and around Robe town, Bale zone, Ethiopia. Seven soil samples(three from dump sites and four from farm lands) were collected and analyzed throughdifferent methods for analyzing the physicochemical parameters like, pH Sand/Silt/ClayContent, MC, OM. and the heavy metals including Cr, Cd, Cu, Fe, Zn and Pb, wereinvestigated using Flame atomic absorption spectrophotometer (FAAS). The analyzedresult of all sites revealed that, high moisture content % (14.83 ± 2.57to 19.96 ± 0.72), pHslightly acidic except S2 which is slightly basic, (5.77 ± 0.08 to 7.60 ± 0.33),high organicmatter % (13.83 ± 0.49 to 16.60 ± 0.90), sand % (53.00 ± 4.51 to 65.33 ± 2.42), silt %(19.33 ± 1.03 to 24.84 ± 4.62), clay % (11.33 ± 1.03 to 19.50 ± 2.50) sandy nature of soilwere observed and the concentration of heavy metals such as: Cr (32.53 ± 3.51 to 41.81 ±1.06) ppm, Cd (0.57 ± 0.21 to 0.93 ± 0.24) ppm, Cu (26.54 ± 0.68 to 37.44 ± 2.72) ppm, Zn(66.98 ± 1.09 to 170.48 ± 1.51) ppm Fe (33483.55 ± 1470.02 to 49012.18 ± 2692.20) ppmand Pb (18.04 ± 0.37 to 20.77 ± 0.46) ppm were obtained. The results showed that all ofthe assessed heavy metals below maximum permissible limit except Fe, which is abovemaximum permissible limit that recommended by Ewers, Based on the results obtainedfrom the study the level of metals concentrations safe for agricultural activities. Butdifferent measures must be taken to minimize additional soil pollution.