Compost Magazine

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Potential of Biochar-Compost to Improve Problem Soils Revealed in New Study

8th Feb 2023

A new study published in Science Direct by Qian et al. has found that biochar-compost, the combination of biochar and compost, is a highly promising and efficient method of soil improvement – especially when used with problem soils.

The researchers looked at the impact of biochar-compost in various problem soils.  These soils were classified depending on which climatic zone they were in, abiotic stresses in the area and contaminants (such as metal) in the soil.

The study found that in temperate soils biochar-compost can help mitigate the high mineralization rate of soil organic matter. It also helped tackle phosphorus deficiency and aluminum toxicity and improved crop yields.

In temperate soils, compost enriched with biochar can help to achieve long-term sustainable management by sequestering carbon and improving soil properties. In dry and saline soils, biochar-compost can reduce the threat of soil water scarcity or high salt content, helping to prevent deterioration in soil quality.

When it comes to soils contaminated with heavy metals or organic pollutants, the study also found that biochar-compost performs better than biochar or compost alone. 

The study concluded that biochar-compost is an effective and efficient way to improve various problem soils and can have a positive effect on crop yields and soil conditions. The benefits, the researchers argued, came from combining the different properties of compost and biochar.

However, challenges still remain in terms of practical application and cost-effectiveness. The authors suggested further research in order to address these challenges and promote the application of biochar-compost in problem soil improvement.

What is biochar?

Biochar is a charcoal-like material that is made from burning organic matter such as wood, crop residues, and animal manure in a low oxygen environment. It can be used to speed up the composting process, and is used as a soil amendment to improve soil fertility, increase water retention and reduce nutrient leaching. Biochar can also be used to sequester carbon, reducing the amount of carbon dioxide in the atmosphere.

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