Forests harbour major parts of global carbon stock and inhabit a significant amount of terrestrial biodiversity. A minimum of one quarter of all forest dwelling taxa depend directly or indirectly on deadwood. Two main factors that determine biodiversity in deadwood are microclimate and host tree species with varying importance to different taxonomic groups. However, it remains unclear if the effect of host tree species and microclimate decrease in increase along with increase in trophic levels. This proposal is based on two unique experimental setups which allow to untangle the effects of tree species and sun exposure. In the first experiment, 108 logs of six tree species have been exposed under closed canopies, on open meadows and under artificial shade (18 subplots arranged in six plots). Branch-bundles of 42 tree species were exposed on three sun-exposed and three shaded plots in the second experiment. The obtained data will use network diversity estimates based on Hill numbers and next generation sequencing to untangle the influence of microclimate and host tree species on diversity of saproxylic organisms in multi-trophic levels. In detail, the proposed project will test if a) the importance of microclimate on species diversity and network diversity decrease with increasing trophic level, and if b) the importance of host tree properties on species diversity and network diversity decrease with increasing trophic level.
Stemmler-Stiftung (T 0206/333937/2019)