A recent study published in Bioresource Technology explored the effects of biochar on microbial necromass carbon (MNC) during the composting of chicken manure. MNC, a stable organic carbon component derived from the remains of dead microorganisms, plays a crucial role in carbon stabilization and humification in compost. This 45-day experiment examined compost with and without biochar addition, revealing that MNC content ranged from 24.9 to 77.9 g/kg, constituting 5.77% to 21.3% of total organic carbon.

The addition of biochar significantly boosted MNC levels by 29.2% through improvements in composting conditions, such as 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 balance and nutrient availability. Biochar also promoted the humification process, enhancing the formation of humus—a stable carbon-rich substance vital for improving soil quality. The study found a strong correlation between humic acid and both bacterial and fungal necromass carbon, suggesting that microbial byproducts are integral to humus formation.

This research offers new insights into how microbial necromass contributes to stable carbon in composting and highlights biochar’s role in enhancing compost quality. By facilitating microbial carbon pump activity, biochar may serve as a valuable tool for increasing carbon sequestration in composting systems, helping to mitigate environmental impacts and improve soil health.