Occurrence patterns of lichens on stumps in young managed forests

PLoS One. 2013 Apr 24;8(4):e62825. doi: 10.1371/journal.pone.0062825. Print 2013.

Abstract

The increasing demand for forest-derived bio-fuel may decrease the amount of dead wood and hence also the amount of available substrate for saproxylic ( = dead-wood dependent) organisms. Cut stumps constitute a large portion of dead wood in managed boreal forests. The lichen flora of such stumps has received little interest. Therefore, we investigated which lichens that occur on stumps in young (4-19 years), managed forests and analyzed how species richness and occurrence of individual species were related to stump and stand characteristics. We performed lichen inventories of 576 Norway spruce stumps in 48 forest stands in two study areas in Central Sweden, recording in total 77 lichen species. Of these, 14 were obligately lignicolous, while the remaining were generalists that also grow on bark, soil or rocks. We tested the effect of characteristics reflecting successional stage, microclimate, substrate patch size, and the species pool in the surrounding area on (1) total lichen species richness, (2) species richness of obligately lignicolous lichens and (3) the occurrence of four obligately lignicolous lichen species. The most important variables were stump age, with more species on old stumps, and study area, with similar total species richness but differences in occupancy for individual species. Responses for total lichen species richness and species richness of obligately lignicolous lichens were overall similar, indicating similar ecological requirements of these two groups. Our results indicate that species richness measurements serve as poor proxies for the responses of individual, obligately lignicolous lichen species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biodiversity
  • Ecosystem
  • Lichens*
  • Picea / microbiology
  • Sweden
  • Time Factors
  • Trees*
  • Wood / microbiology*

Grants and funding

This study was supported by the Swedish Energy Agency (grant nr 30651-1) and by Future Forests, a multidisciplinary research programme supported by the Foundation for Strategic Environmental Research (MISTRA), the Swedish Forestry Industry, the Swedish University of Agricultural Sciences (SLU), Umeå University, and the Forestry Research Institute of Sweden. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.