The influence of stand density on the structure of harvestmen communities (Opiliones) in a submountain beech forest

Abstract

Modification of forest stand density by thinning is a common silvicultural practice implemented in management of production forests. However, changes in the stand density can entail considerable changes to the present forest environment and communities. The current knowledge about the effect of stand density modification on the local animal communities is based mainly on the flagship groups such as carabid beetles or birds. We focused our study on harvestmen. We explored how the stand density influences species composition of this species communities in submountain beech forests. The study was conducted in the Kováčovská dolina valley (Kremnické vrchy Mts, Central Slovakia) in 1997 and 1998, the method used was pitfall trapping. In total, 9 harvestmen species from 5 families were recorded. Prior to our research, the forest stands at the study locality were subject to thinning interventions the intensity of which influenced the structure of the local harvestmen communities. The most pronounced was the effect of very intensive thinning with stand density reduced below 0.5. From the recorded species, four preferred forest stands with lower stand density (Lophopilio palpinalis, Oligolophus tridens, Nemastoma lugubre, Trogulus nepaeformis), two species (Platybunus bucephalus, Dicranolasma scabrum) preferred forest stands with higher stand density. Generalization of the observed pattern requires to explore a wider spectrum of beech forests.