Log-diversity and abundance of dead wood dependent bracket fungi and bryophytes, a comparison between spruce woodland key habitats and adjacent production forests in Östergötland, Sweden.

Dead wood in forests are essential habitat for a wide range of fungal, insects, lichens and bryophyte species. The main threat to dead wood dependent species is lack of substrate, which aggravates their ability to reach and colonize a new substrate. Inventories of woodland key habitats (WKHs) is a method to map forests with high biological value in Sweden, and these areas may benefit dead wood dependent species. The aim of this study was to compare spruce dominated WKHs with adjacent production spruce forests (APFs), regarding (1) log diversity, (2) log characteristics and (3) abundance of selected species on logs. The study was conducted in Östergötland County in Sweden, seven spruce WKHs (≥ 60% spruce) and seven APFs of three different types (two clear-cuts, two dominated by trees < 20 cm and three dominated by trees > 20 cm) were investigated. Data of eight wood dependent species (three bryophytes and five bracket fungi), log diversity, six log characteristics and two environmental factors were collected. In a total area of 4.27 ha, 210 logs (105 logs in WKH and APF each) were studied and the results show that there were significantly higher amount of coarse logs, distribution area of species, number of logs/ha, diameter, decay class and humidity inside WKHs compared with APFs. The total distribution area of species was approximately 85% larger in WKHs. Bark cover was slightly less in WKHs and sun exposure was significantly higher and humidity was lower in clear-cuts. According to the current study, WKHs are important for conservation of wood depending species due to the higher amount and diversity of coarse dead wood. Furthermore, it is necessary to put aside larger amount of coarse dead wood inside production forests, together with changed logging techniques to increase the suitable substrate for dead wood dependent species