Response of ground beetle diversity to the habitat structural heterogeneity of different clearing types in boreal pine forests

Currently, human activities create modern infrastructures in forest ecosystems, e.g., natural gas pipeline clearings, firebreaks and power-line corridors, which can modify forest environment conditions and contribute to the formation of open, extended linear habitat. The present study revealed that three main types of clearings in boreal pine forests contributed to the formation of specific assemblages of ground beetles due to the variability of their environmental conditions. The clearings with more heterogeneous and structurally complex vegetation, such as fire-breaks, can support the higher carabid species diversity. On the other hand, high intensity management practices such as plowing lead to the reduction in structural complexity of habitats and induce low species diversity, but higher ground beetle abundance in natural gas pipeline clearings than in forests. In contrast to species richness and diversity, the ground beetle functional richness and diversity in the clearings increased compared to the control forests. In addition, the species composition, indicator species, and species traits were noticeably different from those of the forest ground beetle assemblages. The main variables driving carabid diversity parameters were plant height, soil pH, salinity, moisture and bare soil proportion. Therefore, natural gas pipeline clearings, firebreaks and power-line corridors can be considered alternative habitats within pine forests.