Weberknechte (Arachnida: Opiliones) in Mischbeständen aus Fichte und Buche im Vergleich zu Fichten- und Buchenreinbeständen – eine Studie im Solling

In the Solling mountains (Southern Lower Saxony, Germany) a block design study was carried out in 18 old (> 90 yrs) and middle-aged (58 - 89 yrs) spruce, beech, and mixed forest stands (spruce/beech), arranged in six blocks, each consisting of a spruce, a beech, and a mixed forest stand, to investigate the effect of the forest stand type on the diversity and structure of epigeic macrofauna communities. In each age class, the fauna was sampled for one year by means of soil core samples, ground photo eclectors, and pitfall traps. The results for the harvestmen presented in this contribution focus on pitfall trap catches. In each age class, the numbers of individuals of the harvestmen species and the species density as well as the cover and diversity of the ground vegetation were significantly highest in the more open spruce or spruce and mixed forest stands, according to a nonparametrical twofactorial analysis of variance. Important extrinsic factors influencing the diversity and structure of the harvestmen communities are habitat diversity, stratification of the vegetation, and space for locomotory activity. Additionally, in the present study information about the phenology of the harvestmen species is given. In the Solling mountains 16 harvestmen species have been recorded to date