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Updated: Sep 5, 2025
09:39
Physical, Chemical and Biological Characterization of Six Biochars Produced for the Remediation of Contaminated Sites
Published on: November 28, 2014
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Immobilization on anionic metal(loid)s in soil by biochar: A meta-analysis assisted by machine learning
Yinjie Zhang1, Meng Ren1, Yiming Tang1
1College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Journal of Hazardous Materials
|July 6, 2022
Summary
Biochar effectively immobilizes soil metals like chromium, antimony, and vanadium, improving soil and crop quality. However, its effect on arsenic immobilization is inconsistent, requiring further research.
Area of Science:
- Environmental Science
- Soil Science
- Geochemistry
Background:
- Soil metal pollution is a critical environmental issue in China.
- Biochar is a common soil remediation agent, but its effectiveness on anionic metal(loid)s is unclear.
- Anionic metal(loid)s like arsenic pose significant risks to soil and crop health.
Purpose of the Study:
- To conduct a meta-analysis on biochar's immobilization of anionic metal(loid)s (As, Cr, Sb, V).
- To assess biochar's impact on metal(loid) bioavailability and plant uptake.
- To identify key factors influencing biochar's remediation performance.
Main Methods:
- Meta-analysis of 597 data records from 70 publications.
- Analysis of four metal(loid)s: arsenic (As), chromium (Cr), antimony (Sb), and vanadium (V).
- Subgroup analysis to evaluate immobilization effects based on metal(loid) type and soil/biochar properties.
Main Results:
- Biochar significantly immobilizes Cr, Sb, and V in soil, reducing their mobility and plant bioavailability.
- Biochar's immobilization effect on arsenic (As) was inconsistent across studies.
- Soil pH and biochar pH were identified as critical factors influencing metal(loid) immobilization.
Conclusions:
- Biochar is effective for immobilizing Cr, Sb, and V, enhancing soil and crop quality.
- Further research is needed to optimize biochar application for consistent arsenic immobilization.
- Tailoring biochar properties and modifications can improve the remediation of anionic metal(loid)s in soil.
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