Traits of collembolan life-form indicate land use types and soil properties across an European transect

• pH strongly negatively correlated to species richness across land use types.
• No significant differences in richness between forest sites and open habitats.
• Functional diversity significantly higher in forest sites than open habitats.
• Forest sites shelter more eu-edaphic species than open habitats.
• Components of functional diversity provide a clearer picture on biodiversity shifts.

Land use changes are among the main factors shaping diversity patterns of soil fauna in European ecosystems. However, current knowledge on soil fauna biodiversity levels across land use types to establish baseline values with monitoring purposes are still lacking. Also, only few initiatives have been including functional components of soil fauna on biodiversity monitoring, despite the noticeable link between soil organisms and aboveground ecosystem services. Here, we analyzed the differences of collembolan taxonomic and functional diversity across an European transect with sites comprising different land use types (forests, grasslands and arable lands) and characteristics in terms of habitat conditions and soil properties. No clear relation was found between collembolan species richness and the site typology established in this study. However, community traits of life-forms responded to the gradient of site properties and indicated different land use types based on the higher proportion of eu-edaphic species in forested sites, in comparison to grasslands and arable lands. Among the environmental variables, pH was the main soil parameter influencing both collembolan richness and community weighted mean of life-forms, and was negatively correlated to both biodiversity components.The effects of pH may also reflect the influence of land use history and management practices in different European ecosystems and more suitable traits related to pH preferences, and tolerance should be further investigated for collembolan species. Our results suggest that functional diversity may provide a clearer picture on soil fauna diversity changes across different land use types and site properties. So components of functional diversity based on community traits should be included in the ‘indicator shopping basket’ of soil biodiversity monitoring studies across European ecosystems.