The microlandscapes of tree trunks: the effect of lichen and tree-level characteristics on arthropod communities

Landscape ecologists frequently invoke a patch-mosaic analogy to describe patterns of different land covers across kilometres-extent landscapes. Patches of different species of lichen growing along a tree trunk can be viewed as a scaled-down version of this pattern. An advantage of working in these microlandscapes of tree trunks is that a stand of trees of the same species represents experimental replicate landscapes; something difficult to do for landscapes at the more traditional large extents. Here, we use such a microlandscape system to test how microlandscape patch patterns affect invertebrate community patterns within them. We hypothesized that trees with more diverse lichen communities would house more diverse arthropod fauna. We used a handheld vacuum to sample arthropods on lichen-covered balsam fir (Abies balsamea) boles on the Avalon Peninsula, Newfoundland, Canada and replicated this sampling with five trees per stand across nine stands growing in different mesoclimate conditions. Model selection showed arthropod abundance and diversity are affected by variation in lichen community composition and significantly so at the most pristine site. Total arthropod diversity was statistically positively correlated to total lichen cover. We further explore how a microlandscape such as this can be used to inform landscape ecology theory and applications across scales. This article is part of the theme issue 'Life in natural microcosms'.