Zhang, 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 addition affects soil carbon stock by altering keystone fungal species and necromass abundance and oxidase activities in forest and paddy soils. Pedosphere. https://doi.org/10.1016/j.pedsph.2024.06.007

A recent study published in Pedosphere explores how adding biochar to soil influences soil carbon storage by affecting fungal communities, their necromass, and enzyme activities. Biochar, a carbon-rich product obtained from pyrolyzing organic material, can enhance soil carbon retention by mediating extracellular electron transfer, a process facilitated by fungi.

Researchers conducted a mesocosm experiment to observe the effects of biochar produced at low (300°C, BL) and high (700°C, BH) temperatures on forest and paddy soils in southern China. They found that biochar significantly impacts soil organic carbon (SOC) retention, with BL showing an 84.0% retention rate, higher than BH’s 76.3%.

The study revealed distinct differences in how biochar affects fungal communities in forest and paddy soils. In forest soils, BL increased fungal abundance by 230%, whereas BH reduced fungal abundance in paddy soils by 20.8%. This difference is attributed to the varying roles of BL and BH in the soil: BL acts as an electron shuttle and BH as a geological capacitor.

BL’s application in forest soils enhanced fungal abundance and necromass while reducing peroxidase activity by 32.1%, leading to decreased SOC degradation. This was due to fungi like Talaromyces, Umbelopsis, and Trichoderma having higher carbon use efficiency. Conversely, BH increased Fusarium abundance in paddy soils, which elevated polyphenol oxidase activity and promoted SOC degradation.

Overall, the study concludes that biochar modifies soil environments and fungal activities, influencing SOC storage differently in forest and paddy soils. These findings highlight biochar’s potential role in sustainable soil management practices.