Reconciling carbon quality with availability predicts temperature sensitivity of global soil carbon mineralization.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38437541.
- Also identified by DOI 10.1073/pnas.2313842121 and PMC identifier 10945789.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Soil organic carbon (SOC) mineralization is a key component of the global carbon cycle. Its temperature sensitivity Q<sub>10</sub> (which is defined as the factor of change in mineralization with a 10 °C temperature increase) is crucial for understanding the carbon cycle-climate change feedback but remains uncertain. Here, we demonstrate the universal control of carbon quality-availability tradeoffs on Q<sub>10</sub>. When carbon availability is not limited, Q<sub>10</sub> is controlled by carbon quality; otherwise, substrate availability controls Q<sub>10</sub>. A model driven by such quality-availability tradeoffs explains 97% of the spatiotemporal variability of Q<sub>10</sub> in incubations of soils across the globe and predicts a global Q<sub>10</sub> of 2.1 ± 0.4 (mean ± one SD) with higher Q<sub>10</sub> in northern high-latitude regions. We further reveal that global Q<sub>10</sub> is predominantly governed by the mineralization of high-quality carbon. The work provides a foundation for predicting SOC dynamics under climate and land use changes which may alter soil carbon quality and availability.