Disentangling the processes driving plant assemblages in mountain grasslands across spatial scales and environmental gradients

Details

Ressource 1Download: Scherrer_etal2018_JE_inj-press.pdf (1049.23 [Ko])
State: Public
Version: Author's accepted manuscript
License: Not specified
Serval ID
serval:BIB_ED921CCF992F
Type
Article: article from journal or magazin.
Collection
Publications
Title
Disentangling the processes driving plant assemblages in mountain grasslands across spatial scales and environmental gradients
Journal
Journal of Ecology
Author(s)
Scherrer D., Mod H., Pottier J., Dubuis A., Pellissier L., Vittoz P., Götzenberger L., Zobel M., Guisan A.
ISSN
1365-2745
ISSN-L
0022-0477
Publication state
Published
Issued date
2019
Peer-reviewed
Oui
Volume
107
Number
1
Pages
265-278
Language
english
Abstract
1. Habitat filtering and limiting similarity are well-documented ecological assembly processes that hierarchically filter species across spatial scales, from a regional pool to local assemblages. However, information on the effects of fine-scale spatial partitioning of species, working as an additional mechanism of coexistence, on community patterns, is much scarcer.
2. In this study, we quantified the importance of fine-scale spatial partitioning, relative to habitat filtering and limiting similarity, in structuring grassland communities in the western Swiss Alps. To do so, 298 vegetation plots (2 m × 2 m ) each with five nested subplots (20 cm × 20 cm) were used for trait based assembly tests (i.e. comparisons with several alternative null expectations), examining the observed plot and subplot level α-diversity (indicating habitat filtering and limiting similarity) and the between-subplot β-diversity of traits (indicating fine-scale spatial partitioning). We further assessed variations in the detected signatures of these assembly processes along a set of environmental gradients.
3. We found habitat filtering to be the dominating assembly process at the plot level with diminished effect at the subplot level, while limiting similarity prevailed at the subplot level with weaker average effect at the plot level. Plot-level limiting similarity was positively correlated with fine-scale partitioning suggesting that the trait divergence may result from a combination of competitive exclusion between functionally similar species and environmental micro-heterogeneities. Overall, signatures of assembly processes only marginally changed along environmental gradients but the observed trends were more prominent at the plot than at the subplot scale.
Synthesis: Our study emphasises the importance of considering multiple assembly processes and traits simultaneously across spatial scales and environmental gradients to understand the complex drivers of plant community composition.

Keywords
community assembly, environmental gradient, habitat filtering, limiting similarity, niche differentiation, spatial partitioning, trait convergence, trait divergence
Web of science
Create date
29/06/2018 17:42
Last modification date
20/08/2019 17:15
Usage data