Biochar potential to relegate metal toxicity effects is more soil driven than plant system: A global meta-analysis. (20th September 2021)

• Record Type: Journal Article
• Authors: Rehman, Abdul; Arif, Muhammad Saleem; Tufail, Muhammad Aammar; Shahzad, Sher Muhammad; Farooq, Taimoor Hassan; Ahmed, Waqas; Mehmood, Tariq; Farooq, Muhammad Raza; Javed, Zeeshan; Shakoor, Awais
• Is Part Of: Journal of cleaner production. Volume 316(2021)
• Publication Date: 2021-09-20
• Subjects: Potentially toxic metals -- Soil remediation -- Physico-chemical parameters -- Metals immobilization; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2021.128276
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Pollution from potentially toxic metals (PTMs) is one of the most pressing global environmental challenge with soaring human health concerns. It is now critical to seek out effective remediation technologies to control PTMs in the terrestrial environment. Biochar has piqued the interest of researchers due to its ability to immobilize PTMs, particularly in soil, with the assumption that biochar having unique physico-chemical properties may influence PTM mobility. A meta-analysis was performed using 1503 observations extracted from 80 peer-reviewed articles to determine: (a) the effects of various physico-chemical properties of biochar on the bioavailability of PTMs (As, Cd, Cu, Ni, Pb, Zn) in soil and plants, and (b) the best specification of physico-chemical properties of biochar for effective remediation of these PTMs. The findings revealed that the reduction rate of PTM bioavailability is heavily influenced by the physico-chemical properties of both biochar and soil. The physico-chemical parameters of biochar that have effective response to PTMs immobilization were as; 101–500 m 2 g −1 surface area, neutral to alkaline pH, pyrolysis temperature > 500 °C, with best application rate of 1.1–3%. However, overall results indicate that the biochar, with given specification of physico-chemical attributes, can decrease the bioavailability of PTMs by 40% in soil and 22% in plants. Moreover, edaphic factors such as soil pH, texture, and crop type can also influence the biochar mediated PTMs adsorption and transformation under field or pot conditions. Furthermore, research gaps remain to be filled in order to investigate the efficiency, high specificity, and secondary pollution aspects of biochar, particularly on large-scale applications as an amendment for PTM remediation. Graphical abstract: Image 1 Highlights: Eighty peer reviewed publications were used to conduct this meta-analysis. Biochar addition can reduce PTMs concentration in soil by 40% and in plants by 22%. Biochar pyrolyzed at >500 °C with 101–500 m 2 g −1 surface area showed effective results. Immobilization of PTMs can be a function of physicochemical properties of biochar. Criteria should be established for uniform classification of biochar.