THE COMPARISON OF ORIBATID MITE (ACARI: ORIBATIDA) COMMUNITIES ON VARIOUS PATCHES IN THE SEMINATURAL MEADOW

摘要

The heterogeneity of oribatid communities is important factor influencing the usage of oribatids as bioindicators of environmental quality. There are indices that oribatid communities differ in the range of one locality. The aim of this study was to describe the differences and correlate them to vegetation cover on seminatural meadow near Rfcany (Central Bohemia). The oribatid were sampled on seven different vegetation patches. These patches hosted 42 oribatid species and members of genus Phthiracarus, Brachychochthonius and family Oppiidae, altogether in 5505 specimens. Different vegetation patches inhabited by partly different oribatid communities can be distinguish in the condition of one seminatural meadow, though it seems to be a homogeneous biotope. The main difference showed the disturbed parts of meadow characterized by Tecto-cepheus velatus (Michael 1880) and Liebstadia similis (Michael 1888) and marginal zones characterized by forest inhabitant Chamobates voigtsi (O u d e m a n s 1902), meadow inhabitant Minulhozetes semirufus (C.L. Koch 1841) and non-specific (in biotope preference) Oppia spp. The most similar were the plots in the middle of meadow with following dominant species: Scheloribates laevigatus (C.L. Koch 1836), Scheloribates latipes (C.L. Koch 1844), Cemtozetes mediocris B e r 1 e s e 1908, they differ in dominace of Minuthozeles semirufus (C.L. Koch 1841). Redundancy analysis estimating effect of plant species composition on composition of mite communities was marginally significant. Given the small sample size here, this result should be taken indication that the relationship between plant and mite species community composition is really strong. The cluster of meadow species was associated to grass Fesluca rubra and Poa trivialis, while Minuthozetes semirufus and Tectocepheus velatus were not. The interaction with vegetation cover confirmed previously published observation, but does not explain all variability. The rest of heterogeneity in oribatid communities should be explained by different moisture and the effect of immigration in the marginal zones.