Summary: | This study was an investigation of epiphytic lichen communities in mid-rotation (45 to 55 years old) managed stands of jack pine (Pinus banksiana) and black spruce (Picea mariana) in northern Ontario. Lichen community structure was compared between pine and spruce stands, and relationships between community structure and environment (substrate, microclimate, and stand-level parameters) were explored. We also assessed habitat associations of lichens with differing growth forms and functional traits. Nonmetric multidimensional scaling was used to analyze community structure, and results showed that differences between pine and spruce stands were most strongly related to stand basal area and light levels, but were also associated with other factors such as branch diameter. In addition, distinct differences in occurrence patterns between functional groups were observed, with fruticose lichens more common in pine stands, and asexual foliose lichens more common in spruce stands. This study represents the first detailed examination of epiphytic lichen community composition in boreal plantation forests in North America. Our results suggest that the conifer species chosen to regenerate a harvested stand will influence epiphytic lichen communities, which may have further implications for ecosystem processes such as nutrient cycling, and for wildlife species dependent on lichens, such as woodland caribou (Rangifer tarandus caribou).
|