Assessing simultaneous immobilization of lead and improvement of phosphorus availability through application of phosphorus-rich biochar in a contaminated soil: A pot experiment

Hanbo Chen; Ying Feng; Xing Yang; Bingshuang Yang; Binoy Sarkar; Nanthi Bolan; Jun Meng; Fengchang Wu; Jonathan W C Wong; Wenfu Chen; Hailong Wang

doi:10.1016/j.chemosphere.2022.133891

Assessing simultaneous immobilization of lead and improvement of phosphorus availability through application of phosphorus-rich biochar in a contaminated soil: A pot experiment

Chemosphere. 2022 Jun:296:133891. doi: 10.1016/j.chemosphere.2022.133891. Epub 2022 Feb 5.

Authors

Hanbo Chen¹, Ying Feng², Xing Yang³, Bingshuang Yang⁴, Binoy Sarkar⁵, Nanthi Bolan⁶, Jun Meng⁷, Fengchang Wu⁸, Jonathan W C Wong⁹, Wenfu Chen⁷, Hailong Wang¹⁰

Affiliations

¹ Agronomy College, Shenyang Agricultural University, Shenyang, Liaoning, 110866, China; Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong, 528000, China.
² Shengyuan Environmental Monitoring Co. Ltd., Shaoxing, Zhejiang, 311800, China.
³ Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong, 528000, China.
⁴ Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Zhejiang A&F University, Hangzhou, Zhejiang, 311300, China.
⁵ Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom.
⁶ School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia.
⁷ Agronomy College, Shenyang Agricultural University, Shenyang, Liaoning, 110866, China.
⁸ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
⁹ Institute of Bioresource and Agriculture, Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China.
¹⁰ Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong, 528000, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Zhejiang A&F University, Hangzhou, Zhejiang, 311300, China. Electronic address: hailong.wang@fosu.edu.cn.

PMID: 35134406
DOI: 10.1016/j.chemosphere.2022.133891

Abstract

Soil lead (Pb) contamination is often caused by anthropogenic activities. In this study, a pot experiment was conducted to assess the effect of biochars derived from pig-carcass (PCBC) and branches of oriental-plane tree (OPBC) on the bioavailability, redistribution, and phytoavailability of Pb and P, as well as the growth of Ipomoea aquatica Forsk in a Pb-contaminated soil. Application of PCBC increased the total and available P concentrations in the soil as compared to the control, and enhanced the concentrations of labile P and sparingly labile P via direct exogenous P input and improvement of soil pH. Both biochars facilitated P accumulation in plant shoots and roots. Sequential extraction of soil Pb confirmed that biochar application facilitated the transformation of mobile Pb into stable fractions, with greater effects from PCBC than OPBC. Hence, biochar application significantly decreased the soil DTPA-extractable Pb by 90.2% (PCBC) and 64.0% (OPBC) compared to the control, consequently reducing Pb uptake by plants. The Pb immobilization by biochar was driven by the biochar-induced increase of soil pH, Pb-phosphate/carbonate precipitation, ion exchange between Pb²⁺ and biochar-derived cations (e.g., Ca²⁺ and K⁺), and surface complexation with functional groups (e.g., carboxyl, hydroxyl, CO). Application of PCBC simultaneously increased the biomass of plant roots and shoots, by 1.8- and 0.6- folds, respectively. Overall, PCBC showed a potential to function as an effective amendment in the immobilization of Pb and alternative P fertilizer to improve degraded soils.

Keywords: Alternative fertilizer; Bioavailability; Heavy metal; Sequential extraction; Soil remediation.

MeSH terms

Animals
Biological Availability
Cadmium / analysis
Charcoal
Lead
Phosphorus*
Soil
Soil Pollutants* / analysis
Swine

Substances

Soil
Soil Pollutants
biochar
Cadmium
Charcoal
Phosphorus
Lead