Modified Biochar as a More Promising Amendment Agent for Remediation of Pesticide-Contaminated Soils: Modification Methods, Mechanisms, Applications, and Future Perspectives

With the acceleration of the process of agricultural modernization, many pesticides (insecticides, fungicides, and herbicides) are applied to the field and finally brought into the soils, causing serious damage to the environment. The problem of pesticide pollution has become increasingly prominent. This has highlighted the urgent need for effective and efficient remediation treatment technology for pesticide-contaminated soils. Biochar has a high specific surface area, high porosity, and strong adsorption capacity, making it a soil amendment agent and carbon fixation agent that can improve soil health and enhance adsorption capacity for pesticides to remediate contaminated soils. Recently, efforts have been made to enhance the physicochemical and adsorption properties of biochar by preparing modified biochar, and it has been developed to expand the application of biochar. Specifically, the following aspects were reviewed and discussed: (i) source and modification methods of biochar for pesticide remediation; (ii) the effect of biochar on the environmental fate of remediating pesticides; (iii) the effect of biochar on pesticide-contaminated soils; and (iv) potential problems for the large-scale promotion and application of biochar remediation of pesticides. In conclusion, this review may serve as a reference and guide for pesticide remediation, hence reducing the environmental concerns associated with pesticides in soil.