Long-term effects of stump removal and tree species composition on the diversity and structure of soil fungal communities

• Published in: FEMS microbiology ecology Vol. 96; no. 5; p. 1
• Main Authors: Modi, Dixi, Simard, Suzanne, Bérubé, Jean, Lavkulich, Les, Hamelin, Richard, Grayston, Sue J
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01-05-2020
• Subjects: Abundance; Birch trees; Community structure; Composition; Decomposing organic matter; Disease control; Ecology; Ectomycorrhizas; Environmental aspects; Fermented food; Forest management; Forest practices; Fungi; Humus; Impact analysis; Long-term effects; Microbial colonies; Microbiological research; Microbiology; Plant species; Regeneration; Relative abundance; Root rot; Soil fungi; Soil layers; Soil microbiology; Soil structure; Soils; Species composition; Species diversity; Trees; Canada; forest; mycobiome; Armillaria root rot; fungi; stumping
• ISSN: 0168-6496; 1574-6941
• DOI: 10.1093/femsec/fiaa061

Stump removal is a common forest management practice used to reduce the mortality of trees affected by the fungal pathogen-mediated root disease, Armillaria root rot, but the impact of stumping on soil fungal community structure is not well understood. This study analyzed the long-term impact of stumping and tree species composition on the abundance, diversity and taxonomic composition of soil fungal communities using internal transcribed spacer (ITS) marker-based DNA metabarcoding in a 48-year-old trial at Skimikin, British Columbia. A total of 108 samples were collected from FH (fermented and humus layers), and soil mineral horizons (A and B) from stumped and unstumped plots of six tree species treatments (pure stands and admixtures of Douglas-fir, western red-cedar and paper birch). Fungal α-diversity in the A horizon significantly increased with stumping regardless of tree species composition, while β-diversity was significantly affected by stumping in all the horizons. We also observed that the relative abundance of the saprotrophic fungal community declined while that of the ectomycorrhizal fungal community increased with stumping. In conclusion, increase in ectomycorrhizal fungal associations, which are positively associated with tree productivity, suggests that stumping can be considered a good management practice for mitigating root disease and promoting tree regeneration.