Tree species and microhabitat affect forest bog spider fauna

Peat bogs are among the most threatened habitats in Central Europe. They are characterized by stagnant water with low pH and lower nutrient content compared to the surrounding habitats. The flora and fauna of peat bogs comprised of many habitat specialist and rare species. We explored the differences in spider fauna of European spruce and Scots pine forests. Furthermore, we assessed the effect of microhabitat diversity in the bog forests of the Poiana Stampei peat bog complex, Bucovina, Romania. We collected numerous rare and cold-adapted species. .We found a strong effect of forest type, presumably due to the different microclimatic conditions of the forests. European spruce forests had lower species richness of ground-dwelling fauna than Scots pine forests; however, we found contradictory results for vegetation-dwelling species richness. Hummocks had a more positive effect on the ground-dwelling spiders of Scots pine than in European spruce forests, presumably due to the more open structure of sphagnum hummocks than ground level. However, this effect was negative for vegetation dwellers. The cold-adapted species with restricted ranges are vulnerable to climate change, and bogs may serve as important micro-refugia for them. Central European bogs are isolated and highly threatened by anthropogenic activities, such as drainage, peat extraction, and eutrophication. The deterioration habitat quality of peat bogs will result in a significant loss in the regional species pool of the Carpathians.