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ABSTRACT Managing soils to increase organic carbon storage presents a potential opportunity to mitigate and adapt to global change challenges, while providing numerous co‐benefits and ecosystem services. However, soils differ widely in their potential for carbon sequestration, and knowledge of biophysical limits to carbon accumulation may aid in informing priority regions. Consequently, there is great interest in assessing whether soils exhibit a maximum capacity for storing organic carbon, particularly within organo–mineral associations given the finite nature of reactive minerals in a soil. While the concept of soil carbon saturation has existed for over 25 years, recent studies have argued for and against its importance. Here, we summarize the conceptual understanding of soil carbon saturation at both micro‐ and macro‐scales, define key terminology, and address common concerns and misconceptions. We review methods used to quantify soil carbon saturation, highlighting the theory and potential caveats of each approach. Critically, we explore the utility of the principles of soil carbon saturation for informing carbon accumulation, vulnerability to loss, and representations in process‐based models. We highlight key knowledge gaps and propose next steps for furthering our mechanistic understanding of soil carbon saturation and its implications for soil management.
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This content will become publicly available on July 22, 2026
“Social ontologies of soil: what is soil?, what’s it for? And what should we do with it"
Double session: How does dirt become soil? Categorizations of soil in the agricultural sciences. Organized and chaired by Catherine Kendig with presenters Roberta Millstein, Denise Hossom, Robert Meunier, Aja Watkins, and Özlem Yilmaz Silverman. Biennial meeting of the International Society for the History, Philosophy, and Social Studies of Biology. University of Porto, Porto, Portugal.
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- Award ID(s):
- 2240749
- PAR ID:
- 10632517
- Publisher / Repository:
- https://ishpssb2025.icbas.up.pt
- Date Published:
- Edition / Version:
- https://ishpssb2025.icbas.up.pt
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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