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Abstract AimsBryophytes can cover three quarters of the ground surface, play key ecological functions, and increase biodiversity in mesic high‐elevation conifer forests of the temperate zone. Forest gaps affect species coexistence (and ecosystem functions) as suggested by the gap and gap‐size partitioning hypotheses (GPH,GSPH). Here we test these hypotheses in the context of high‐elevation forest bryophyte communities and their functional attributes. Study SiteSpruce–fir forests on Whiteface Mountain, NY,USA. MethodsWe characterized canopy openness, microclimate, forest floor substrates, vascular vegetation cover, and moss layer (cover, common species, and functional attributes) in three canopy openness environments (gap, gap edge, forest canopy) across 20 gaps (fir waves) (n = 60); the functional attributes were based on 16 morphologic, reproductive, and ecological bryophyte plant functional traits (PFTs). We testedGPHandGSPHrelative to bryophyte community metrics (cover, composition), traits, and trait functional sensitivity (functional dispersion;FDis) using indicator species analysis, ordination, and regression. ResultsCanopy openness drove gradients in ground‐level temperature, substrate abundance and heterogeneity (beta diversity), and understory vascular vegetation cover. TheGPHwas consistent with (a) the abundance patterns of forest canopy indicator species (Dicranum fuscescens,Hypnum imponens, andTetraphis pellucida), and (b)FDisbased on threePFTs (growth form, fertility, and acidity), both increasing with canopy cover. We did not find support forGPHin the remaining species or traits, or forGSPHin general; gap width (12–44 m) was not related to environmental or bryophyte community gradients. ConclusionsThe observed lack of variation in most bryophyte metrics across canopy environments suggests high resistance of the bryophyte layer to natural canopy gaps in high‐elevation forests. However, responses of forest canopy indicator species suggest that canopy mortality, potentially increased by changing climate or insect pests, may cause declines in some forest canopy species and consequently in the functional diversity of bryophyte communities.
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Tropical forest composition and function across space and time: Insights from diverse gradients in Área de Conservación Guanacaste
Abstract Environmental gradients have played a pivotal role in the history and development of plant ecology and are useful for testing ecological and evolutionary theory. Área de Conservación Guanacaste is a spatio‐temporal mosaic of forests that have evolved continuously across elevation, topography, soil types, succession, and annual and inter‐annual climatic change. Studies of plant ecology across diverse gradients ofACGhave shaped functional ecology, successional theory, community assembly, plant–herbivore interactions, among many other fields. In this review, we synthesize the, perhaps overlooked, role plant ecological studies ofACGhave had on our understanding of tropical forest dynamics. We outline present‐day processes that will have major impacts on forest dynamics ofACGin the future and highlight howACGwill continue to shape future research priorities in plant ecology. Abstract in Spanish is available with online material.
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- Award ID(s):
- 1833358
- PAR ID:
- 10452814
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Biotropica
- Volume:
- 52
- Issue:
- 6
- ISSN:
- 0006-3606
- Page Range / eLocation ID:
- p. 1065-1075
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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