Abstract

Logging residues, i.e. thin branches and tree tops, are increasingly harvested as a source of bioenergy. However, many saproxylic species use this type of wood, thus bioenergy harvesting will decrease their breeding substrate. The magnitude of the threat to these species depends mainly on the availability of alternative breeding substrates. Fine wood exists in large quantities as dead bottom branches attached to living trees. In this paper, we hypothesized that such branches were not an alternative breeding substrate for the species breeding in logging residues. We tested the hypothesis by comparing the saproxylic beetle communities of (1) spruce twigs retained within clear-cuts and (2) the dead bottom branches attached to living spruce. Abundance of beetles was measured by the area covered by larval galleries. Ten taxa were encountered. Species density was higher in twigs retained in clear-cuts compared with dead bottom branches. The two twig types had very different species composition, with four species significantly associated with twigs retained on clear cuts, and two with dead bottom branches. This suggests that dead bottom branches are not an alternative substrate for species using logging residues. We relate the results to models estimating habitat loss for various organisms found across areas subjected to bioenergy harvest and suggest that this difference needs to be taken into account. An intensive removal of logging residues poses a larger threat than the models suggest.

Published in

Forestry
2017, Volume: 90, number: 1, pages: 82-87

SLU Authors

• Manak, Vita

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Jonsell, Mats

  • Department of Ecology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Zoology
Forest Science
Ecology


Publication identifier

DOI: https://doi.org/10.1093/forestry/cpw028

Permanent link to this page (URI)

https://res.slu.se/id/publ/79580