Evaluating the Effects of Fertilizers on Bioavailable Metallic Pollution of soils, Case study of Sistan farms, Iran

Present study determines not only the total amounts of metals (Cr, Cu and Pb) in superficial agricultural soil of Sistan area in Eastern Iran, but also the chemical partitioning of these elements in seven statistically selected cases. The analysis was run for local soil, soil treated by non-contaminated organic, compost and chemical fertilizers as well as soil treated by metal-contaminated fertilizers. The sampling campaign was done in Zabol University research farm in 2009. The grab samples were taken from seven different cases, the chemical partitioning analysis was performed and metallic concentrations were detected using FAAS. It may be concluded that the bioaccessibility of metals Cu and Cr would be increased in case of imposed contamination where the soil is treated with all three kinds of fertilizers. Although a relatively similar distribution pattern is seen between anthropogenic and geopogenic portions of bulk concentration in all three kinds of fertilizers, chemical fertilizer seems to manifest a more risky condition. According to the results achieved by cluster analysis, a close correlation exists between Cu and Cr behavior which may be attributed to the geological texture of the study area. In accordance with the results gained by partitioning analysis, IPOLL index values also show contaminated chemical fertilizer as the most risky case for all three metals in comparison with others.