Abstract
Free-living saprotrophic fungi and symbiotic mycorrhizal fungi affect organic matter dynamics differently because of contrasting ecological adaptations. We investigated how mass-loss, C:N-ratio and stable isotope dynamics of leaf litter and humus substrates depended on presence of living tree roots and associated fungal communities in a forest-to-tundra ecotone over three years. Litter mass-loss was stimulated by tree roots, contrary to a Gadgil effect. Increases in the litter nitrogen pool and δ15N suggested import of nitrogen from deeper soil by the dominating saprotrophic fungi. Over time, humus first lost, then gained, mass, and corresponding shifts in δ15N and δ13C suggested fluctuating pools of fine roots and fungal mycelium. Ectomycorrhizal tree roots consistently reduced longer-term humus mass-gain, counteracting positive effects of ericoid roots and associated fungi. Across all substrates, mass dynamics correlated with the balance between ectomycorrhizal and litter-saprotrophic fungi, both linked to mass-loss, and ericaceous shrubs and associated fungi, linked to mass-gain.
| Originalsprog | Engelsk |
|---|---|
| Artikelnummer | 101359 |
| Tidsskrift | Fungal Ecology |
| Vol/bind | 71 |
| Antal sider | 13 |
| ISSN | 1754-5048 |
| DOI | |
| Status | Udgivet - 2024 |
Bibliografisk note
Funding Information:The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: KEC reports financial support was provided by European Commission Seventh Framework Programme for Research and Technological Development. AM reports financial support was provided by Independent Research Fund Denmark, DFF Nature and Universe. Two of the authors, KEC and BDL, of this submission serves in the editorial board of the journal Fungal Ecology. KEC serves as one of the editors of the Special Issue to which the manuscript is submitted. KEC has not been involved in the review or editorial process of this submission. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.This work was funded by the Swedish University of Agricultural Sciences, Sweden, a Marie Curie Intra European Fellowship within the 7th European Community Framework Programme, European Commission (PIEF-GA-2008-221056) and the Independent Research Fund Denmark, DFF Nature and Universe (ref 2032-00064B). We thank Abisko Scientific Research Station for logistical support, R Gadjieva for help with amplicon preparation and Signe Lett, Jonatan Andersen and Marie Glahn for field assistance. LGC Genomics (Berlin, Germany) conducted the sequencing.
Funding Information:
This work was funded by the Swedish University of Agricultural Sciences, a Marie Curie Intra European Fellowship within the 7 th European Community Framework Programme (to KEC) and the Independent Research Fund Denmark, DFF Nature and Universe (ref 2032-00064B). We thank Abisko Scientific Research Station for logistical support, R Gadjieva for help with amplicon preparation and Signe Lett, Jonatan Andersen and Marie Glahn for field assistance. LGC Genomics (Berlin, Germany) conducted the sequencing.
Publisher Copyright:
© 2024 The Authors