Functional role of microarthropods in soil aggregation

Soil aggregation has received a lot of attention in the last years; however, the focus was mostly on soil microorganisms or larger soil fauna, especially earthworms. The impact of the large group of microarthropods, e.g. Collembola and Acari, is nearly unknown and hence underrepresented in the literature. Here we propose and discuss potential direct and indirect mechanisms of how microarthropods could influence this process with the focus on collembolans, which are in general a relatively well studied taxon. Indirect mechanisms are likely to have larger impacts on soil aggregation than direct effects. The variety of indirect mechanisms based on the provision of organic material like fecal pellets, molts and necromass as food source for microorganisms is high and given available evidence we propose that these mechanisms are the most influential. We highlight the need for overcoming the challenges of culturing and handling of these animals in order to be able to design small scale experiments and field studies which would enable us to understand the role of the different functional groups, their interaction with other soil fauna and the impact of land use practices on soil aggregation.