Exploring potential biodiversity indicators in boreal forests

The present study evaluates indicators in Swedish spruce forests. We ask wh ether different species groups co-vary in their occurrence and to what exte nt species richness and composition is predictable from habitat structures. We studied 10 boreal spruce forest stands constituting a gradient in degre e of selective logging. Occurrences of vascular plants, bryophytes, epiphyt ic lichens and wood-inhabiting fungi as well as habitat structures was inve ntoried. In addition, in five of the stands, beetles were sampled with wind ows traps. Total species richness was correlated with several habitat facto rs, mainly particular substrates and degree of forestry impact. However, th e richness of a set of species regularly used as indicators did not correla te with habitat factors. Correlation in species richness among different or ganism groups were few and scale dependent. Only lichens and vascular plant s formed nested subset patterns (i.e. species composition at poorer sites i s subsets of the species present at richer sites) among the study sites. Th e study shows that in this forest type one cannot a priori assume that rich ness in one group of species correlated with richness in other, and measure s of single habitat features may be relevant only to particular groups of s pecies. Instead, monitoring and inventories should be based on a set of fac tors reflecting important aspects for different groups of organisms and if indicator species are to be used these should be chosen from several specie s groups.