Authors: Gossmann, Anika;

It has been hypothesized that certain wood-dependent organisms are decreasing due to increased competition from species favored by forestry or warming climate. If so, species assemblages on clear-cuts in the north are becoming more similar to managed forests in the south, while species favored by clear-cuts may spread also to other forests and compete with northern species. By calculating “Community temperature indices” and measuring inner-log temperature, we test in this research project for the first time hypotheses related to this. We expect that i) southern species are in the north favored by the increased level of light induced by clear-cuttings, and ii) that inner-log temperature affects saproxylic beetle assemblages. In 2021, we installed 450 eclector traps along a 1200 km long latitudinal gradient in Sweden. These traps consisted of 1.5 m long spruce logs and caught all emerging beetles from April until September. They were set up under three different light levels and their inner-log temperature was measured hourly. Now, we are analyzing the collected data and at the conference we will be ready to present our newly acquired knowledge on how microclimate alters wood-dependent species composition.