Forest soils store large amounts of carbon (C) and nitrogen (N), yet how predicted shifts in forest composition will impact long‐term C and N persistence remains poorly understood. A recent hypothesis predicts that soils under trees associated with arbuscular mycorrhizas (
Plant–soil feedback (
- NSF-PAR ID:
- 10054385
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 21
- Issue:
- 5
- ISSN:
- 1461-023X
- Page Range / eLocation ID:
- p. 646-654
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract AM ) store less C than soils dominated by trees associated with ectomycorrhizas (ECM ), due to slower decomposition inECM ‐dominated forests. However, an incipient hypothesis predicts that systems with rapid decomposition—e.g. mostAM ‐dominated forests—enhance soil organic matter (SOM ) stabilization by accelerating the production of microbial residues. To address these contrasting predictions, we quantified soil C and N to 1 m depth across gradients ofECM ‐dominance in three temperate forests. By focusing on sites whereAM ‐ andECM ‐plants co‐occur, our analysis controls for climatic factors that covary with mycorrhizal dominance across broad scales. We found that whileECM stands contain moreSOM in topsoil,AM stands contain moreSOM when subsoil to 1 m depth is included. Biomarkers and soil fractionations reveal that these patterns are driven by an accumulation of microbial residues inAM ‐dominated soils. Collectively, our results support emerging theory onSOM formation, demonstrate the importance of subsurface soils in mediating plant effects on soil C and N, and indicate that shifts in the mycorrhizal composition of temperate forests may alter the stabilization ofSOM . -
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1. Ants are widely regarded as ‘ecosystem engineers’ because their nest construction and contributions to nutrient cycling change the biological, chemical, and physical properties of the soil around their nests. Despite increasing attention to ant manipulation of soil ecosystems, the extent to which many common species influence soil properties, as well as nutrient uptake and community composition of plants near nests, is still unknown.
2. This study tested hypotheses that activities of a common subalpine ant,
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4. Overall, this study uncovers significant impacts of
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Summary Belowground biota can deeply influence plant invasion. The presence of appropriate soil mutualists can act as a driver to enable plants to colonize new ranges. We reviewed the species of ectomycorrhizal fungi (
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