Soil functionality at the roadside: Zooming in on a microarthropod community in an anthropogenic soil

Earth movements for road construction give rise to nutrient-poor anthrosols. Early onset of soil processes in these environments has been reported on the basis of plant cover establishment. Evidences of full soil functionality, however, would reveal the emergence of a self-sustainable ecosystem on these man-made substrates. The aims of the present study involved (1) assessing soil functionality on six-year-old road embankments by means of the QBS index, based on microarthropod communities (2) elucidating soil properties responsible for the composition of soil microartrhopod communities, and (3) exploring the practical implications of soil quality for road embankment management. Road embankments were functional with QBS values comparable to those found in natural systems (>100). Soil quality in these environments depended on soil organic carbon dynamics. Among the 36 arthropod groups found, Acari and Collembola dominated the soil community. Variation in microarthropod community composition was best explained by higher abundances of Brachypilina (Oribatida, Acari) and Symphypleona (Collembola). These trends in soil community structure were intimately linked to soil organic carbon content, clay content and humidity. Given its relevance, the acknowledgment of the early functionality attained by these roadside anthrosols should lead to the revision of current protocols for roadslope monitoring and management.