贵州高原不同母岩风化土壤微生物固碳特征分析OA

This work aims to investigate the similarities and differences of organic carbon sequestration characteristics in weathered soils from different parent rocks in a subtropical high-altitude region.We focused on natural soil profiles developed from limestone,basalt,and purple sandstone under the same elevation and climatic conditions on the Guizhou Plateau.This study analyzed the vertical distribution patterns of soil organic carbon(SOC)and its components across these weathering profiles,and further elucidated the carbon sequestration characteristics of soil microorganisms using metagenomic sequencing technology.Results indicate that SOC content in soils derived from limestone and basalt was significantly higher than that in purple sandstone soils,with SOC and its components showing a clear decreasing trend with increasing soil depth.Proteobacteria,Acidobacteria,Chloroflexi,Actinobacteria,and Gemmatimonadetes were the dominant carbon-sequestering microbial phyla common to all three soil types.In terms of microbial carbon fixation pathways,the reductive citrate cycle(rTCA)was identified as the primary carbon sequestration mechanism shared across the three parent rock types,and the abundant carbon source provided by limestone weathering further enhanced its carbon sequestration capacity.This study provides a scientific basis for assessing soil carbon cycling in subtropical high-altitude regions.