Epiphytic lichens in Norwegian coastal spruce forest historic logging and present forest structure

Current forestry policies worldwide aim at conserving and restoring biodive rsity in managed forests. In this respect, epiphytic lichens have become a focal group in studies of how logging and silvicultural methods can be adju sted to mimic and restore old-growth conditions. We addressed this issue in a retrospective study in the coastal spruce (Picea abies) forest region of central Norway, surveying 31 old forest sites in order to relate a selecte d group of epiphytic macrolichens (Fuscopannaria ahlneri, Lobaria pulmonari a, L. scrobiculata, Nephroma spp., Platismatia norvegica, Pseudocyphellaria crocata, Ramalina thrausta, and Sphaerophorus globosus) to forest stand ch aracteristics and previous logging history. The lichens were associated wit h brook ravines, F. ahlneri and P. crocata mostly so, being 10 times more a bundant in ravine valley bottoms than on adjacent slopes and plateaus. All species used spruce trees as their main substrate, but L. pulmonaria, L. sc robiculata, and Nephroma spp. preferred scattered deciduous trees. Ramalina thrausta and S. globosus occurred more frequently on older trees and incre ased in number with increasing stand age. In ravine valley bottoms lichens tended to increase in number with increasing tree density (due to increased amount of branches), whereas the opposite was the case on slopes and plate aus (due to higher proportion of high-branched trees). All locations had be en selectively cut two or more times during the last 100 yr, with a total h arvested volume of 31-124% of present-day standing volumes. After controlli ng for covariation with stand structure, variables describing logging histo ry (harvested volume, number of cuts, minimum standing volume, and years si nce last cut) did not explain significant parts of the variation in present -day abundance of the selected lichens. The results suggest that moderate s elective cuttings may prove an acceptable management option to sustain viab le lichen assemblages on private land.