Biodiversity and community composition of ground-dwelling invertebrates across three disturbance regimes in a sub-boreal spruce forest

Abstract

Natural and anthropogenic disturbances are closely tied to changes in biodiversity and ecological communities. Previous research has reported that ground-dwelling invertebrates exhibit a range of responses to different disturbance regimes. To investigate changes to community composition and biodiversity following forest harvest, we used pitfall traps to sample ground-dwelling invertebrates in the Aleza Lake Research Forest in British Columbia’s central interior. We collected and compared pitfall trap catches using family-level identifications in new plantations (11 years post-harvest), stands with a harvest history (>40 years since harvest), and old growth stands (no record of harvest). Community compositions differed among the three disturbance regimes and Bray-Curtis dissimilarity indicated that β-diversity was highest in new plantation stands. A small but non-significant increase in α-diversity was also observed in new plantation stands compared to the other two forest types. These findings are consistent with previous work in the boreal forest, which reported increases in ground-dwelling invertebrate biodiversity following disturbance. Three families (Agriolimacidae, Formicidae, and Lycosidae) were significantly associated with new plantation stands and could potentially be used as indicators of forest disturbance or to monitor stand succession post-harvest. This study provides a foundation for future work on invertebrate biodiversity in sub-boreal spruce forests, which would benefit from using species-level identifications and measuring environmental conditions associated with disturbance regimes.