Oribatid mite communities

The fauna and community structure of oribatid mites (Acari: Oribatida) in the Pskov Region of Russia is not yet comprehensively studied. Until now not much attention has been paid to soil communities of bogs and open landscapes of this area. The aim of this study was to compare the community composition of oribatid mites in different habitats in the environs of the Polistovsky National Nature Reserve (Pskov Region, Russia). We found 56 oribatid species in this area during our sampling campaign in 2010. Of these 16 have not been recorded in the Pskov Region before. Forest habitats were the richest in species within the examined territory. The highest faunistic similarity of oribatid communities was found between raised bogs and transition bogs. The mite faunistic composition in these two types of habitats was in turn quite similar to that in spruce forests. At the same time secondary habitats such as meadows hosted fewer oribatid species and were faunsitically distinct from the other habitats. Analysis of the rank abundance distribution of oribatid species indicated a disturbed state of oribatid communities in meadows even after their abandonment 20-25 years ago. The abundance of all oribatid ecomorphs besides surface-dwelling mites was similar and not significantly different across habitats. We assume that the relatively high number of previously unrecorded oribatid species for the Pskov Region in the research area is related to the considerable age of landscapes in the Polistovsko-Lovatskaya peat bog system and immigration of oribatid mites with transiting birds. More detailed comparative study of the oribatid fauna and community structure in the Polistovsky Reserve is needed to discover driving forces of the revealed community structure and diversity. Key words: oribatid mites, Pskov Region, Polistovsky Nature Reserve, soil animals, ecological structure.