Afforestation modulates soil microbial community and carbon fraction along 21-m deep profiles

Restoration of organic carbon pools and biological soil functions under afforestation focuses on the topsoil horizons despite terrestrial subsurface soil being predicted to host comparable levels of microbial diversity. As an object of the study, we have taken the typical watershed at the Loess Plateau to ensure the similarity of soil formation factors except for land use and consider the area's significant contribution to climate change regulation of the region. We have explored the changes in the soil carbon pools, including particulate (POC), mineral associated (MAOC), microbial necromass carbon, microbial diversity, and abundance of carbon cycling genes along 21-m deep profiles 30-y since afforestation with shrub (Caragana microphylla) or tree species (Robinia pseudoacacia)