DOI: 10.5061/dryad.8gtht76r9
title: Data from: Towards a better ecological understanding of metacommunity stability: A multiscale framework to disentangle population variability and synchrony effects

description: 1. Despite great progress in our understanding of the mechanisms governing
 ecosystem stability in local communities, we still lack knowledge at a
 larger spatial scale. Studying the stability of metacommunities requires
 assessing the temporal stability and synchrony of populations across space
 and organizational levels. Previous attempts to disentangle these effects
 have provided limited ecological interpretations, and conceptual
 improvements are needed to identify the underlying ecological processes.
 2. We propose an extended framework aiming at disentangling simultaneously
 the relative effects of population stability and different types of
 synchronies on metacommunity stability. We adapted previous methods of
 decomposing stability into a new set of indices associated with clearer
 ecological hypotheses. Particularly, we provide synchrony indices that are
 not affected by statistical properties of the metacommunity but focus on
 species responses to environment, demography, and interactions. We applied
 this framework to a unique dataset describing the sorted biomass of
 individual plant populations, across 12 communities of a species-rich
 meadow, and for 16 years. The communities were sampled in different
 treatments of fertilization and dominant removal to evaluate the effect of
 environmental heterogeneity on stability. 3. We found higher stability at
 a larger spatial scale, mainly due to statistical averaging (portfolio
 effect). The variability of individual populations was an important
 determinant of the stability of the whole metacommunity. Consistent with
 the hypothesis of a common response to environmental conditions, we found
 that the fluctuations of populations were mostly synchronized (within and
 between species) at a large spatial scale and tended to destabilize the
 metacommunity. On the other hand, opposite fluctuations (anti-synchrony)
 between populations occurred at the local scale, probably due to local
 species interactions. 4. Synthesis Our framework appears as a powerful
 tool to test how ecological processes occurring simultaneously at
 different spatial and organizational scales affect the stability of
 metacommunities. This study advances our ecological understanding of the
 processes underlying the stability of species-rich environments. --
description: The dataset
 was collected on a long-term experiment led by Jan
 Lepš.
 It
 contains the annual biomass of plant species growing in a species-rich
 grassland, over the period
 1999-2014. Vegetation was harvested once a year, at the peak
 of the growing season, in the central 0.25 m² of 12 plots representing
 different fertilization and dominant removal
 treatments. The values correspond to the measured biomasses of
 each species which have been sorted by hand thanks to the help of many
 students and volunteers over the years.
 More technical details of biomass sorting are
 described in Appendix 1 of Lepš <em>et al.</em> (2018)
 <em>Ecology</em>.
description: For more information on the data, please contact Jan Lepš:
 suspa@prf.jcu.cz<br>