Abstract

Effects of snag characteristics on saproxylic beetles were studied in an area of managed beech forest in southern Sweden. A snag survey was combined with a beetle survey using 30 small window traps directly attached to beech snags. The total number of species was lower in the snags which were most decayed than in the three younger decay classes, while the number of red-listed species remained the same regardless of the stage of decay. The number of fresh wood species declined and the number of rot hole species increased with increasing snag decay. The diversity of fungicolous and decayed wood species peaked at the intermediate stage of decay in the snags. CCA ordination confirmed that the stage of decay in the snags was most important for species composition, followed by sun exposure. There were no general differences in species density and composition between managed and unmanaged stands. Our study suggests that most species are able to find suitable habitat within a radius of a few kilometres and that the total amount of habitat in an unfragmented forest area is more important for species diversity than the spatial distribution of this habitat. Our data also shows that species diversity increases with habitat diversity. Snags formed from giant beech trees seem to be particularly important for rare species living in rot holes. We conclude that for a high species diversity there is a requirement for snags in different stages of decay, size and degree of sun exposure.

Keywords

CWD; Decay stage; Habitat guilds; Species richness; Sun exposure; Window traps

Published in

Journal of Insect Conservation
2009, Volume: 13, number: 5, pages: 515-528

SLU Authors

• Brunet, Jörg

  • Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use
Forest Science


Publication identifier

DOI: https://doi.org/10.1007/s10841-008-9200-3

Permanent link to this page (URI)

https://res.slu.se/id/publ/19772