Soil mite communities (Acari: Gamasina) from different ecosystem types from Romania

The study aimed to characterize the distribution of soil mite populations (Acari: Gamasina) from several terrestrial ecosystems, some of them little studied in Romania as well as in Europe. We studied the Gamasina communities in seven ecosystem types from the Doftana Valley, Prahova County: Luzulo-Fagetum beech forest; Medio-European limestone beech forest of the Cephalanthero-Fagion; Pannonic woods with Quercus petraea and Carpinus betulus; Galio-carpinetum oak - hornbeam forests; Alpine rivers and their ligneous vegetation with Myricaria germanica; alluvial shrub, characteristic for a hilly-mountain area, with Salix purpurea; adjacent area to an inland cliff ecosystem. A total of 240 soil samples, 63 species and 475 individuals were analysed. The samples were taken from May 2006 till September 2010. The highest numerical abundance and species diversity was found in the area located nearby to an inland cliff; which is an early succession stage ecosystem. Considering the dominance and constancy indices quantified for mites from all investigated areas, the highest percent was recorded by the recedent-subrecedent and accessory-accidental species. Based on similarity index two different characteristic groups of gamasid populations were delimited: one for deciduous forests and one for shrubs. DCA ordination successfully handled the variation in soil mite species communities taking account of the soil type.