Microbially Driven Iron Cycling Facilitates Organic Carbon Accrual in Decadal Biochar-Amended Soil

• DOI: 10.1021/acs.est.3c09003
• Publication Date: 2024-07-05T16:36:47Z
• Authors: Haohua He; Jie Liu; Zhipeng Shu; Yalan Chen; Zezhen Pan; Chao Peng; Xingxing Wang; Fengwu Zhou; Ming Zhou; Zhangliu Du; Ke Sun; Baoshan Xing; Zimeng Wang
• Keywords: Soil carbon; Cycling; Carbon fibers

Soil organic carbon (SOC) is pivotal for both agricultural activities and climate change mitigation, biochar stands as a promising tool bolstering SOC curtailing soil dioxide (CO2) emissions. However, the involvement of in dynamics underlying interactions among biochar, microbes, iron minerals, fresh matter (FOM, such plant debris) remain largely unknown, especially soils after long-term amendment. We therefore introduced FOM to with without decade-long history amendment, performed microcosm incubations, evaluated well microbial properties. Biochar amendment resulted 2-fold accrual over decade attenuated FOM-induced CO2 emissions by approximately 11% during 56-day incubation through diverse pathways. Notably, facilitated microbially driven reduction subsequent Fenton-like reactions, potentially having enhanced extracellular electron transfer use efficiency long run. Throughout cycling processes, physical protection minerals could contribute accumulation debris preservation, alongside direct adsorption occlusion particles. Furthermore, slurry experiments, sterilization ferrous stimulation controls, confirmed role microbes hydroxyl radical generation biotic sequestration biochar-amended soils. Overall, our study sheds light on intricate abiotic mechanisms governing upland