06/15/2016, Sebastien Villeger MARBEC, 11h00 Montpellier

Publié le :

Assessing the complementary facets of functional diversity
RIAE room (University of Montpellier, building 24, 1st floor)

Trait-based approaches are increasingly applied in community ecology to assess spatial patterns and temporal trends of functional diversity to ultimately understand how human impacts affect ecosystem functioning. Several methodological frameworks have been proposed to compute the diversity of traits values present in a species assemblage and the similarity of traits values between several assemblages. However, methodological choices could have deep implications on the results since some approaches have biases (e.g. functional dendrogram) and because indices have different properties (e.g. accounting for relative biomass of species or only for their traits values). Here I will present user-oriented guidelines for each of the three steps to compute functional diversity : (1) selecting a set of traits and measuring them in a set of species assemblages, (2) building a multidimensional space of high quality to place all the species according to their respective traits values, (3a) computing complementary indices describing the facets of the distributions of species and of their biomass in this space and/or (3b) computing complementary indices of functional dissimilarity between assemblages. I will also show some graphical tools to illustrate functional diversity patterns.

MARBEC MARine Biodiversity, Exploitation and Conservation, is a research unit which includes the staff of 4 organizations: IRD, IFREMER, UM and CNRS. Its objective is the study of marine biodiversity in lagoon coastal and offshore ecosystems, at different integration levels, molecular, individual, population and community aspects and the way humans use this biodiversity.