Scree habitats: ecological function, species conservation and spatial-temporal variation in the arthropod community

Earlier studies suggested that the Mesovoid Shallow Substratum (MSS), a subterranean network of voids immediately under the soil and scree horizon, might play an important role in the life cycle of some troglobitic species. No ecological studies have been conducted to test whether this terrestrial shallow subterranean habitat only plays an important role for a few subterranean or preferential species, or whether it is also important for the soil faunal structure and dynamics. We investigated the spatial and temporal patterns of the arthropod community in the MSS and sub-alpine scree and analysed the correlations with environmental variables. We identified 140 soil-dwelling, characteristic and troglobitic species that inhabited the MSS in different seasonal assemblages. Combined statistical analyses of the environmental factors and seasonal variation in arthropod abundance and biomass emphasized the importance of the MSS as an ecological microrefuge for many soil-dwelling species (including important predators and detritivores) which usually live in the adjacent forests or mountain pastures. Conservation plans for invertebrates should include the protection of the MSS.