We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Beyond bulk: Density fractions explain heterogeneity in global soil carbon abundance and persistence.
- Authors
Heckman, Katherine; Hicks Pries, Caitlin E.; Lawrence, Corey R.; Rasmussen, Craig; Crow, Susan E.; Hoyt, Alison M.; von Fromm, Sophie F.; Shi, Zheng; Stoner, Shane; McGrath, Casey; Beem‐Miller, Jeffrey; Berhe, Asmeret Asefaw; Blankinship, Joseph C.; Keiluweit, Marco; Marín‐Spiotta, Erika; Monroe, J. Grey; Plante, Alain F.; Schimel, Joshua; Sierra, Carlos A.; Thompson, Aaron
- Abstract
Understanding the controls on the amount and persistence of soil organic carbon (C) is essential for predicting its sensitivity to global change. The response may depend on whether C is unprotected, isolated within aggregates, or protected from decomposition by mineral associations. Here, we present a global synthesis of the relative influence of environmental factors on soil organic C partitioning among pools, abundance in each pool (mg C g−1 soil), and persistence (as approximated by radiocarbon abundance) in relatively unprotected particulate and protected mineral‐bound pools. We show that C within particulate and mineral‐associated pools consistently differed from one another in degree of persistence and relationship to environmental factors. Soil depth was the best predictor of C abundance and persistence, though it accounted for more variance in persistence. Persistence of all C pools decreased with increasing mean annual temperature (MAT) throughout the soil profile, whereas persistence increased with increasing wetness index (MAP/PET) in subsurface soils (30–176 cm). The relationship of C abundance (mg C g−1 soil) to climate varied among pools and with depth. Mineral‐associated C in surface soils (<30 cm) increased more strongly with increasing wetness index than the free particulate C, but both pools showed attenuated responses to the wetness index at depth. Overall, these relationships suggest a strong influence of climate on soil C properties, and a potential loss of soil C from protected pools in areas with decreasing wetness. Relative persistence and abundance of C pools varied significantly among land cover types and soil parent material lithologies. This variability in each pool's relationship to environmental factors suggests that not all soil organic C is equally vulnerable to global change. Therefore, projections of future soil organic C based on patterns and responses of bulk soil organic C may be misleading.
- Subjects
CARBON in soils; SOIL profiles; SOIL depth; SOIL erosion; ORGANIC bases; LAND cover
- Publication
Global Change Biology, 2022, Vol 28, Issue 3, p1178
- ISSN
1354-1013
- Publication type
Article
- DOI
10.1111/gcb.16023