Boukhatem, A., Rached, O., Bentellis, A. et al.Promoting the recovery of soil health in As and Sb-polluted soils: new evidence from the biochar-compost option. Environ Sci Pollut Res(2024). https://doi.org/10.1007/s11356-024-35650-3

Restoring soil health in regions polluted with arsenic (As) and antimony (Sb) is critical for environmental sustainability. A recent study explored the impact of using 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 (BC) and municipal solid waste compost (MSWC) to remediate soil from a former Sb mine in Algeria. The study focused on reducing the mobility of these harmful pollutants while enhancing soil’s chemical and biological properties.

The study tested amendments—BC, MSWC, and their mixtures (MIX)—at various concentrations over six months. Key findings include:

• Reduction in Pollutant Mobility: BC, particularly at 10%, was the most effective in reducing labile Sb (by 65%) and As (by 70%), indicating its potential to immobilize these toxic elements.
• Soil Chemistry: MSWC and MIX improved soil pHpH is a measure of how acidic or alkaline a substance is. A pH of 7 is neutral, while lower pH values indicate acidity and higher values indicate alkalinity. Biochars are normally alkaline and can influence soil pH, often increasing it, which can be beneficial More and organic carbon content, though high MSWC concentrations raised electrical conductivity to levels potentially harmful for plant growth.
• Microbial Activity: MSWC significantly increased soil enzyme activities, such as dehydrogenase, which supports microbial metabolism. However, BC alone had negligible effects on biochemical activity.
• Biodiversity Concerns: Both BC and MSWC altered the soil’s microbial diversity, reducing α-diversity and potentially reshaping microbial communities in ways that require further study.

The study suggests that a MIX of 10% BC and MSWC is a balanced approach for chemically and biologically restoring polluted soils. While BC helps immobilize pollutants, MSWC boosts microbial activity. Future research should evaluate the long-term effects on plant growth and the economic feasibility of these solutions.