Biochar Boosts Cadmium Removal in Rice Paddies Through Microbial Processes

Biochar enhances microbial induced carbonate precipitation (MICP) for cadmium (Cd) removal in rice paddies. By stimulating ureolytic bacteria, biochar reduces the need for urea, achieving over 99% Cd removal while minimizing disruption to soil bacterial communities, promoting sustainable agriculture.

October 14, 2024

1–2 minutes

Peng, et al (2024) BiocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More enhances Cd mineralization through microbially induced carbonate precipitation as a soil remediation strategy for rice paddies. *Chemosphere.* https://doi.org/10.1016/j.chemosphere.2024.143441

A recent study published in Chemosphere explores an innovative approach to addressing cadmium (Cd) contamination in rice paddies through microbial induced carbonate precipitation (MICP). This process uses bacteria to precipitate heavy metals as carbonates, reducing their bioavailability. However, conventional MICP requires large amounts of urea, which can harm the soil.

The research team, led by Dinghua Peng, investigated whether biochar, a porous carbon material, could enhance MICP’s effectiveness while reducing the need for excessive urea. They found that biochar significantly stimulated the growth and urease activity of the ureolytic bacterium strain kp-22. This strain, when supported by biochar, was able to immobilize Cd at lower urea levels, achieving a 99% Cd removal rate.

Further experiments revealed that the biochar-supported microbial process (BCM) effectively reduced Cd levels in both flooded and unflooded paddy soils. Importantly, the presence of biochar did not significantly disrupt the broader soil bacterial community, making it a promising candidate for sustainable agricultural soil remediation.

This research highlights biochar’s potential to enhance green technologies like MICP for heavy metal remediation in agriculture, offering a cost-effective and environmentally friendly solution to the challenges of soil contamination. By lowering the need for urea, biochar could make MICP more feasible for large-scale use in rice production.