During 1991-1993 Gamasina communities were investigated in two agricultural
areas in East Slovakia: the East-Slovak Lowland and the Kosice Basin. The
study was carried out in cultivated fields on two different soil types: alb
ic luvisol and eutric fluvisol, which were each replicated at six sites and
sampled at two-month intervals. Species richness of Gamasina varied betwee
n 11-26 species and significantly correlated with content of organic carbon
in the soil. Arctoseius cetratus, Alliphis siculus and Rhodacarellus siles
iacus were dominant species at sites. Abundance of assemblages was generall
y low, nor having a significantly higher mean value on the eutric fluvisol
(280 ind. m(-2)) compared to the albic luvisol (230 ind. m(-2)). The result
s from cluster and ordination analysis of quantitative data showed no effec
t of soil type, composition of Gamasina assemblages being more affected by
geographical area or particular site. Populations of Pachylaelaps pectinife
r, Alliphis siculus and Eugamasoidea nymphs correlated significantly with s
andy mineral content in the soil.