Forest-management types similarly influence soil collembolan communities throughout regions in Germany – A data bank analysis

Abstract

European forest management practices create broad-scale mosaics of tree-species composition and developmental stages, inducing gradients in environmental conditions at landscape scales. However, consistent effects of specific forest-management types on general characteristics of soil microarthropod assemblages could not always be determined. This study aimed to reveal generalizable effects of similar forest-conversion measures using collembolan data extracted from the German soil-zoological data warehouse “Edaphobase”. Data of collembolan assemblages and environmental variables from forest-conversion studies were analyzed from three forest types – deciduous, coniferous and mixed forests – in two German regions (a northern and a southern) with various sites in two areas each. We hypothesized that forest management has a strong effect on soil Collembola and the different forest types induce consistently dissimilar assemblages independent of region. Abundance, diversity and species richness of collembolan assemblages were compared between forest types. Community composition was analysed with cluster analysis and canonical ordinations to reveal similarity patterns and the driving environmental variables. Contrary to our hypothesis, forest conversion caused only small differences in quantitative community variables, most likely due to site-specific influences and high variability. More than a third of the considered species showed preferences for stands with either deciduous or coniferous trees. The collembolan assemblages of the two regions differed from each other, indicating separate species pools. Nonetheless, as opposed to the quantitative metrics, different species compositions did consistently occur between forest types across regions, revealing a gradient from deciduous over mixed to coniferous stands. Collembolan assemblages were primarily associated with dominant tree species (forest stands) and humus forms, while quantitative environmental parameters had low explanatory power. Therefore, forestry measures induce qualitative differences in the soil-habitat, leading to habitat-specific environmental filtering of the regional collembolan species pools and a mosaic of soil microarthropod communities at the landscape level.