Résumé
Aim: Niche differentiation is one mechanism allowing multiple soil invertebrate species to co-occur locally. While ecological niches are represented by species traits, multidimensionality of functional traits has yet been revealed in soil invertebrates. We used two unique global datasets, #GlobalCollembola (43,601 communities) and trait data (1,384 taxa) to reveal assembly processes – filtering and niche partitioning – in Collembola communities across different habitats at both global and European scales. Method: We quantified trait responses using community weighted mean and mean pairwise distance among coexisting species with seven traits: antenna-to-body ratio, body length, pigmentation, coloration pattern, eye number, furca development and reproductive mode. Results: All these traits showed responses. At European scale woodland Collembola were smaller, possessing fewer ommatidia but longer furca and antenna and more parthenogenetic individuals than random expectations. In shrub habitats Collembola were less patterned and their antenna were shorter. Furca development and eye number represented the traits filtered by habitats, while reproductive mode revealed partitioning processes. Body length revealed filtering in shrubs but partitioning in agricultural fields. Antenna-to-body ratio, by contrast, revealed filtering in shrubs but partitioning in woodlands. Coloration pattern contributed to partitioning in agricultural fields but filtering in grasslands, shrubs and woodlands. Body pigmentation, as a filtering trait, however, could only be validated in shrubs. Putting all traits together, local Collembola communities were driven by partitioning in agricultural fields but filtering in shrub habitats. Conclusions: Our study demonstrates multidimensional functional traits underlying community assembly of Collembola. Applying trait-based methods improves our understanding of mechanisms regulating soil biodiversity.