Sorption, desorption, and degradation of pesticides in biochar amended agricultural soils

In recent few years, extensive and inefficient utilization of pesticides prompted genuine soil and water contamination and impacting serious lethal impacts on living beings. To deal with the environmental issues, use of environment-friendly amendments for soil remediation is essential to counteract the presence of pesticides in soil. Biochar has a higher porosity, surface area, pH, abundant functional groups, and highly aromatic structure, mainly depending on the feedstock and pyrolysis temperature and thus, it has emerged as an efficient adsorbent, diminishing the pesticide bioavailability in treated soils. So, it’s important to recognize the effects of biochar and mechanisms on pesticide sorption and desorption in soils. High pyrolysis temperature increases biochar surface area and has a positive effect on pesticide sorption in soil, whereas a lower temperature during pyrolysis has a large number of functional groups attached to biochar thus exerting reducing the pesticide sorption. Thus, to design biochar modifications a rational understanding of effects and mechanisms of biochar action are necessary. This review primarily ascertains dominant properties of biochar including porosity and surface area, pH, surface functional groups, carbon content and aromatic structure, and mineralogical composition, and evaluates the effect of biochar on pesticide sorption, desorption, and degradation in agricultural soils. In addition, a vision for future research prospects has been anticipated by considering the pesticide bioavailability as residues in soil, influence of contaminants in biochar on pesticide removal, pesticide properties and its behavior in biochar amended soils, mutual effect of soil microorganisms and biochar on pesticide degradation and multifunctional use of large- scale application of biochar on agricultural soils.