Multi-source biochar: Effects on composting humification, soil properties and plant growth

Area of Science:

• Environmental Science
• Soil Science
• Agronomy

Background:

• Rising organic waste necessitates sustainable management solutions.
• Biochar from thermochemical conversion of biomass offers potential for compost enhancement and soil improvement.
• Understanding feedstock-specific biochar effects is crucial for optimizing compost and soil applications.

Purpose of the Study:

• To evaluate the impact of five different biochars (kitchen waste, pig manure, sewage sludge, distillers' grains, biogas residue) on compost performance, humification, and soil-plant systems.
• To determine how biochar feedstock influences compost maturity and the structural complexity of humus.
• To assess the effects of biochar-amended compost on soil nutrient availability and plant biomass.

Main Methods:

• Composting experiments to assess humification and compost quality.
• Pot experiments to evaluate soil nutrient availability and plant responses.
• Analytical techniques including parallel factor analysis and partial least squares path modeling.

Main Results:

• Biochar feedstock significantly influenced the composting humification process.
• Biogas residue biochar (BRB) demonstrated the highest specific surface area and significantly increased the humification index (3.72-fold) and humus structural complexity.
• Application of pig manure biochar-amended compost (8%) notably enhanced soil nutrient availability (available phosphorus, 8.55-fold) and plant biomass (5.89-fold).

Conclusions:

• Biochar feedstock exerts specific regulatory effects on compost quality and soil improvement.
• Biogas residue biochar is effective in enhancing compost maturity and humus structure.
• Pig manure biochar-amended compost shows significant benefits for soil nutrient availability and plant growth, highlighting the potential for tailored biochar-compost products in sustainable agriculture.