Beetle Diversity Associated with Forest Structure including Deadwood in Softwood and Hardwood Stands in Nova Scotia

Abstract

Associations between beetles and forest stand characteristics, as well as beetle diversity, were investigated for 41 forest stands in Nova Scotia, Canada. Over 200 morphospecies from 45 Families of beetles were caught using window flight-intercept traps. In both years, correspondence analysis revealed distinct groupings of softwood and hardwood stands based on species assemblages. Multiple regression analysis was used to determine associations between forest variables and total species richness. Analyses were conducted for all stands combined and for hardwood and softwood stands separately. Hardwood stands had greater beetle richness than softwood stands. Within hardwood stands, volume of intermediate-sized deadwood was the best predictor of total species richness. Within softwood stands, volume of well-decayed deadwood was the best predictor of total beetle richness. Deadwood volume was associated with stand age in softwoods, and it appears that over 140 years is required for deadwood volume to reach pre-disturbance levels.