|Title: ||A model-based approach to studying changes in compositional heterogeneity|
|Authors: ||Baeten, Lander ×|
Warton, David I.
Van Calster, Hans
De Frenne, Pieter
Verheyen, Kris #
|Issue Date: ||2014 |
|Series Title: ||Methods in Ecology and Evolution vol:5 issue:2 pages:156-164|
|Abstract: ||1. Non-random species loss and gain in local communities change the compositional heterogeneity between communities over time, which is traditionally quantiﬁed with dissimilarity-based approaches. Yet, dissimilaritis summarize the multivariate species data into a univariate index and obscure the species-level patterns of change, which are central to understand the causes an d consequences of the community ch anges.
2. Here, we propose a model-b ased approach that looks for species-level eﬀects of time period and construct a multiple-site metric as a sum across species to test the consistency of the individual species responses. Species f all into diﬀerent response type s, showing how they in ﬂuence the changes in community heterogeneity.
3. In a comparison with other multiple-site metrics, we illustrate the properties of our method and the diﬀerence sand similarities with other approaches. For instance, our metric estimates the total variation in a community dataset based on species-level contributions, not the compositional dissimilarities between particular sites. Similar to some other approaches, we can distinguish between heterogeneity derived from turnover or richness diﬀerences.
4. Our approach was applied to a set of 23 forest understorey resurvey studies spread across Europe. We show the species gains a nd losses m ay as well decrease or increase levels of community heterogeneity. Although species occurrences and communities have not changed in a consistent way along continental-scale environmental gradients such as climatic conditions, several species shifted in a similar way across the diﬀerent data sets.
5. Testing the signiﬁcance of shifts in species prevalence over time to infer corresponding changes in the compositional heterogeneity among sites provides a very intuitive tool for community resurvey studies. The main strengths of our framework are the explicit consideration of the relative roles of species gains and losses and the straight forward generalization to diﬀerent sets of hypotheses r elated to community changes.
|Publication status: ||published|
|KU Leuven publication type: ||IT|
|Appears in Collections:||Division Forest, Nature and Landscape Research|