Abstract
Soil carbon sequestration arises from the interplay of carbon input and stabilization, which vary in space and time. Assessing the resulting microscale carbon distribution in an intact pore space, however, has so far eluded methodological accessibility. Here, we explore the role of soil moisture regimes in shaping microscale carbon gradients by a novel mapping protocol for particulate organic matter and carbon in the soil matrix based on a combination of Osmium staining, X-ray computed tomography, and machine learning. With three different soil types we show that the moisture regime governs C losses from particulate organic matter and the microscale carbon redistribution and stabilization patterns in the soil matrix. Carbon depletion around pores (aperture > 10 µm) occurs in a much larger soil volume (19–74%) than carbon enrichment around particulate organic matter (1%). Thus, interacting microscale processes shaped by the moisture regime are a decisive factor for overall soil carbon persistence.
| Original language | English |
|---|---|
| Article number | 2098 |
| Journal | Nature Communications |
| Volume | 13 |
| Issue number | 1 |
| ISSN | 2041-1723 |
| DOIs | |
| Publication status | Published - Dec 2022 |
Bibliographical note
Funding Information:This research was funded by the German Research Foundation through two research grants (416883305, 290269257). We thank Claudia Stehr at the Fraunhofer Institute for Microstructure of Materials and Systems IMWS in Halle for Osmium staining and the H?here Landbauschule Rotthalm?nster for access to field sites.
Funding Information:
This research was funded by the German Research Foundation through two research grants (416883305, 290269257). We thank Claudia Stehr at the Fraunhofer Institute for Microstructure of Materials and Systems IMWS in Halle for Osmium staining and the Höhere Landbauschule Rotthalmünster for access to field sites.
Publisher Copyright:
© 2022, The Author(s).