Contribution of Enriched Biochar to the Reduction of the Hydrosoluble Fraction of Some Heavy Metals in an Urban Soil in Ngaoundere, Cameroon

The fertilization by spreading cheap compost coming from unsorted household waste result in the introduction of important quantities of pollutants in the urbain soils. The soluble fraction of heavy metals existing in the soil can produce important ecotoxicological impacts if its percolation and its transfer in the plant or in the soil water is not restricted. These pollutants substances can therefore generate significant damage to the environment and human health. The aim of the present study is to evaluate the capacity of improved biochar to reduce the hydrosoluble fraction of heavy metals present in a polluted urban soil in Ngaoundere. Different proportion of enriched biochar was incorporating in a polluted soil in order to reduce the hydrosoluble fraction of the four heavy metals (Cadmium, Zinc, Copper and Nickel). Analysis showed that enriched biochar increases the pH at 20%. In addition, the reduction of the hydrosoluble fraction of cadmium is total within one week. Finally, the fixation of the hydrosoluble forms of the heavy metals in the polluted soils can limited their transfers in the plants and the waters.