Recently fixed carbon fuels microbial activity several meters below the soil surface

Abstract > 1  m, harbors a substantial share of the global microbial biomass. Currently, it is not known whether microbial activity several meters below the surface is fueled by recently fixed carbon or by old carbon that persisted in soil for several hundred years. Understanding the carbon source of microbial activity in deep soil is important to identify the drivers of biotic processes in the critical zone. Therefore, we explored carbon cycling in soils in three climate zones (arid, mediterranean, and humid) of the Coastal Cordillera of Chile down to a depth of 6 m, using carbon isotopes. Specifically, we determined the 13 C : 12 C ratio (δ 13 14 C : 12 C ratio (Δ 14 2 –C respired by microorganisms. We found that the Δ 14 2 –C was significantly higher than that of the soil organic carbon in all soils. Further, we found that the δ 13 13 C occurs in the upper decimeters of the soils, which is possibly due to stabilization of organic carbon in the deep soil. In conclusion, our study demonstrates that microbial processes in the deep soil several meters below the surface are closely tied to input of recently fixed carbon.

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch

References and Relationships

• Bibliographic citation: Recently fixed carbon fuels microbial activity several meters below the soil surface ; volume:20 ; number:4 ; year:2023 ; pages:827-838 ; extent:12 ; Biogeosciences ; 20, Heft 4 (2023), 827-838 (gesamt 12)

Contributors, Places and Time

• Creator: Scheibe, Andrea ; Sierra, Carlos ; Spohn, Marie

Further information

• DOI: 10.5194/bg-20-827-2023
• URN: urn:nbn:de:101:1-2023033006465207241237
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 14.08.2025, 10:46 AM CEST