Effect of Different Levels of Biochar on the Distribution of the Chemical Fraction of Lead in Two Soils

Abstract

Abstract Soil contamination with heavy metals threatens the quality of agricultural products and human health, where lead is considered one of the most dangerous heavy elements causing damage to microorganisms in the soil and the chemical properties of the soil. The current study investigated the effectiveness of using biochar average (0.0, 7.5, 15.0 and 30.0 g Kg−1) in two types of soil (clayey and sandy soil) contaminated with different concentrations of lead in the form of nitrate (75, 150, and 300 mg Kg−1. After that, chemical fractionation of the element lead (available, bound to carbonates, the residual) was performed in the two types of studied soil. The results showed that biochar had a significant effect on the distribution of lead in the soil samples, and the chemical fraction were taken in descending order of the fraction bound. Bound to carbonate > available > the residual. A larger surface area and negative charge content also make the biochar’s small pores more effective in absorbing heavy elements, allowing it to reduce the toxicity of lead in contaminated soil and make its environment more suitable for the life of microorganisms while improving some of the chemical properties of the soil.