Understanding how abiotic disturbance and biotic interactions determine pollinator and flowering‐plant diversity is critically important given global climate change and widespread pollinator declines. To predict responses of pollinators and flowering‐plant communities to changes in wildfire disturbance, a mechanistic understanding of how these two trophic levels respond to wildfire severity is needed. We compared site‐to‐site variation in community composition ( Wildfire disturbance generally increased species richness and total abundance, but decreased Wildfire disturbance mediated the relative importance of mutualistic associations to
Plant microbiomes are known to influence host fitness and ecosystem functioning, but mechanisms regulating their structure are poorly understood. Here, we explored the assembly mechanisms of leaf epiphytic and endophytic bacterial communities using a subtropical forest biodiversity experiment. Both epiphytic and endophytic bacterial diversity increased as host tree diversity increased. However, the increased epiphytic diversity in more diverse forests was driven by greater epiphytic diversity (i.e. greater
- NSF-PAR ID:
- 10411052
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Ecology
- Volume:
- 111
- Issue:
- 5
- ISSN:
- 0022-0477
- Page Range / eLocation ID:
- p. 970-981
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract β ‐diversity), species richness and abundances of pollinators and flowering plants among landscapes with no recent wildfire (unburned), mixed‐severity wildfire and high‐severity wildfire in three sites across the Northern Rockies Ecoregion, USA. We used variation partitioning to assess the relative contributions of wildfire, other abiotic variables (climate, soils and topography) and biotic associations among plant and pollinator composition to community assembly of both trophic levels.β ‐diversity, of both pollinators and flowering plants. However, reductions inβ ‐diversity from wildfire appeared to result from increased abundances following fires, resulting in higher local species richness of pollinators and flowers in burned than unburned landscapes. After accounting for differences in abundance, standardized effect sizes ofβ ‐diversity were higher in burned than unburned landscapes, suggesting that wildfire enhances non‐random assortment of pollinator and flowering‐plant species among local communities.β ‐diversity of pollinators and flowering plants. The influence of pollinatorβ ‐diversity on flowering‐plantβ ‐diversity increased with wildfire severity, whereas the influence of flowering‐plantβ ‐diversity on pollinatorβ ‐diversity was greater in mixed‐severity than high‐severity wildfire or unburned landscapes. Moreover, biotic associations among pollinator and plant species explained substantial variation inβ ‐diversity of both trophic levels beyond what could be explained by wildfire and all other abiotic and spatial factors combined.Synthesis . Wildfire disturbance and plant–pollinator interactions both strongly influenced the assembly of pollinator and flowering‐plant communities at local and regional scales. However, biotic interactions were generally more important drivers of community assembly in disturbed than undisturbed landscapes. As wildfire regimes continue to change globally, predicting its effects on biodiversity will require a deeper understanding of the ecological processes that mediate biotic interactions among linked trophic levels. -
Abstract Plant genotypic diversity can influence population‐ and community‐level processes, yet we have limited understanding of how these effects vary across environmental gradients that are ubiquitous in nature.
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Summary Leaf decomposition varies widely across temperate forests, shaped by factors like litter quality, climate, soil properties, and decomposers, but forest heterogeneity may mask local tree influences on decomposition and litter‐associated microbiomes. We used a 24‐yr‐old common garden forest to quantify local soil conditioning impacts on decomposition and litter microbiology.
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