Habitat and climate influence beetle and spider communities in boreal forests

Abstract

ABSTRACT Separating the influence of climate and habitat characteristics on forest communities could help better understand their potential sensitivity to environmental change. In this study, we sampled spiders and beetles in similar forest types, located along a ca. 4°C mean annual temperature spatial gradient in the boreal forest zone in Quebec, Canada. Specifically, we aimed to separate the effect on arthropod communities of two habitat-related factors that can be influenced by forest management (stand composition and stand age), and another one that cannot (climate). Overall, spider assemblages tended to be more abundant and species-rich in younger forest stands, while beetle assemblages were more abundant and species-rich in deciduous forest stands. Eight beetle and six spider species were significantly influenced by climate, independently from forest type, whereas 11 beetle and seven spider species were significantly influenced by both forest type and climate. While most of the beetle species affected by climate were associated with warmer locations, several spider species were more abundant in colder locations. By helping to ensure the retention of key forest types along potential dispersal pathways at the landscape level, forest management activities could help the conservation of species belonging to relatively cryptic taxa such as arthropods in a climate change context.