1. Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden
2. Department of Biosystems and Technology, Swedish University of Agricultural Sciences, SE-230 53 Alnarp, Sweden
3. Department of Aquatic Sciences and Assessment, Division of Microbial Ecology, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden
4. Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden