Microbially mediated interactions between enhanced weathering and carbon inputs shift soil organic carbon dynamics
Abstract
Enhanced weathering, adding crushed silicate minerals to soils, is being explored as a way to draw down atmospheric carbon dioxide, but its effects on soil organic carbon remain uncertain. We show that olivine amendments change soil carbon cycling depending on time and on labile carbon availability. In a 55-week soil microcosm experiment, adding olivine alone reduces total soil organic carbon. Adding olivine with glucose initially suppresses microbial carbon uptake, but by week 55 instead boosts microbial biomass and mineral-associated organic matter more than glucose alone, while lowering respiratory carbon loss. These late-stage gains grow stronger alongside geochemical signs of mineral weathering. Nanoscale imaging shows that newly formed soil organic carbon accumulates within pre-existing organic and mineral microsites rather than directly on olivine or newly formed clay surfaces. Our findings suggest that when labile carbon is available, enhanced weathering can increase soil carbon storage primarily through microbial processing, rather than by creating new mineral surfaces for carbon to bind to.
Related
- A physically integrated GNN surrogate for microbially-mediated kinetic reactive transport: PHYGNET
- Assessing the potential and cost of enhanced rock weathering in China
- Response to “Direct Measurement of Carbon Dioxide Removal Due to Enhanced Weathering”
- Enhanced rock weathering in grassland: Impacts of basalt dust on hay meadow soil, forage, and floristic diversity
- Enhanced weathering of glacial rock flour drives coupled inorganic and organic carbon sequestration in a five-year field experiment
BibTeX
@article{sohng2026microbially,
title = {{Microbially mediated interactions between enhanced weathering and carbon inputs shift soil organic carbon dynamics}},
author = {Jaeeun Sohng and Noah W. Sokol and Peter K. Weber and Steffen Schweizer and Seth Whiteaker and Keith Morrison and Radomir Schmidt and Isabel Montañez and Anthony O’Geen and Kate Scow},
journal = {Communications Earth \& Environment},
year = {2026},
month = oct,
doi = {10.1038/s43247-026-04143-1},
url = {https://www.nature.com/articles/s43247-026-04143-1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Microbially mediated interactions between enhanced weathering and carbon inputs shift soil organic carbon dynamics
AU - Jaeeun Sohng
AU - Noah W. Sokol
AU - Peter K. Weber
AU - Steffen Schweizer
AU - Seth Whiteaker
AU - Keith Morrison
AU - Radomir Schmidt
AU - Isabel Montañez
AU - Anthony O’Geen
AU - Kate Scow
PY - 2026
DA - 2026/10/23
JO - Communications Earth & Environment
DO - 10.1038/s43247-026-04143-1
UR - https://www.nature.com/articles/s43247-026-04143-1
AB - Enhanced weathering, adding crushed silicate minerals to soils, is being explored as a way to draw down atmospheric carbon dioxide, but its effects on soil organic carbon remain uncertain. We show that olivine amendments change soil carbon cycling depending on time and on labile carbon availability. In a 55-week soil microcosm experiment, adding olivine alone reduces total soil organic carbon. Adding olivine with glucose initially suppresses microbial carbon uptake, but by week 55 instead boosts microbial biomass and mineral-associated organic matter more than glucose alone, while lowering respiratory carbon loss. These late-stage gains grow stronger alongside geochemical signs of mineral weathering. Nanoscale imaging shows that newly formed soil organic carbon accumulates within pre-existing organic and mineral microsites rather than directly on olivine or newly formed clay surfaces. Our findings suggest that when labile carbon is available, enhanced weathering can increase soil carbon storage primarily through microbial processing, rather than by creating new mineral surfaces for carbon to bind to.
SN - 2662-4435
ER -