Mite community composition across a European transect and its relationships to variation in other components of soil biodiversity

The sustainable use of soils requires the protection of soil biodiversity because of itsimportance in the delivery of ecosystems services. However, no effective indicator exists which wouldallow assessment of the current state of biodiversity and is sensitive to change. This study, which is acomponent of the EcoFINDERS project, examines the use of mites (Acari) as a possible biologicalindicator of soil community composition. Thirty-six sites were sampled across 10 European countriesspanning four bio-climatic zones (Alpine, Atlantic, Continental and Mediterranean) and 3 land uses(arable, grassland and forestry) for both biotic and abiotic variables. Results show a significant effect ofbio-climatic zone on mite communities; in particular, the Mediterranean region had a rather distinctcomposition. Land use type significantly affected mite community composition and there was a distinctassociation with forestry. Cross-taxon congruence among soil taxa was variable and generally weak.Procrustes analysis showed that there was little similarity between the patterns of variation in mitecommunity composition and those of other taxonomic groups (Collembola, Enchytraeidae, Nematodaand microbes). Mite and Collembola communities had the strongest correlation (r=0.4316, p<0.001).There was also variation in the indicator values of individual mite groups. Mesostigmata werecorrelated with soil microbial activity, as assessed using Multiple Substrate Induced Respiration, andProstigmata with Collembola.