Collembolan Assemblages Response to Wild Boars (Sus scrofa L.) Rooting in Pine Forest Soil

Abstract

Collembola are an important component of soil communities in all terrestrial ecosystems. In temperate coniferous forests, they are one of the most numerous invertebrate groups, and disturbances that change their density and structure may have negative effects on soil fertility and productivity. Our goal was to determine whether intensive rooting in the forest floor by wild boars affects edaphic Collembola. Soil samples from three paired rooted and non-rooted plots in Scots pine stands were taken twice a year to study the impact of such bioturbation on forest collembolan assemblages. Substantial changes in the taxonomic and functional structure of the collembolan assemblages were identified in all disturbed plots. The abundance and number of species significantly decreased in the bioturbated forest floor. The shares of atmobiotic and hemiedaphic springtails increased at the expense of epedaphic forms. Most of the differences were evident shortly after grubbing but were not significant a few months later. The decline in moisture in disturbed soil could be an explanatory factor causing the differences in the structure and abundance of collembolan assemblages between the bioturbated and intact plots. Our study revealed that large mammals ubiquitous in forest ecosystems can be an important disturbing factor for soil microarthropods. Intensive wild boar rooting in the forest floor had a strong negative effect on the occurrence and abundance of Collembola. This kind of bioturbation also modified the functional structure of assemblages, which in turn may have important consequences for the soil food web and above- and belowground interactions.