Investigations of Gamasina mites in natural and man-affected soils in Latvia (Acari: Mesostigmata)

Investigations of Gamasina mites in natural and man-affected soils in Latvia (Acari: Mesostigmata) A short overview is presented on Gamasina material collected in 22 natural and man-disturbed habitats in Latvia. Species diversity, average density and species dominance were investigated. Altogether 167 Gamasina species from 14 families were found. The highest number of species was found for field margins and the lowest for pine forests and arable lands affected by calciferous dust. The highest densities of mites were observed for arable lands, and the lowest for coastal meadows. There were no habitats, neither natural nor man-affected, with both a high number of species and high densities. Some specific habitats such as spruce forests polluted by pig slurry and arable lands polluted by calciferous dust had a low number of species and high densities. Generally, man-affected habitats had higher average abundances, whereas natural habitats had higher species diversity. 25 Gamasina species were registered as eudominants or dominants. The most common species was the ubiquitous Veigaia nemorensis. The dominant species differed among polluted habitat types, but were similar for non-polluted sites within a habitat type.