Do wildfires impact community structure and diversity of beetles (Coleoptera) in northern Mongolian forests?: An investigation in Khentey Mountains

Forest fires are part of taiga ecosystem dynamics in northern Mongolia. We studied beetle diversity and community structure in 98 plots at five sites in different forest types (light taiga, mixed taiga, dark taiga, floodplain forest) and under different fire regimes. Each plot included five pitfall traps, one soil and litter sampling and recording of environmental variable measurements. We used Hill numbers, GLMM and RDA to evaluate the data. In total, we collected 2692 individuals of 130 species and 72 genera of beetles, mainly Carabidae, Staphylinidae, Silphidae, and Leidodidae, with Pterostichus eximius occurring in 60% of all plots. Forest fires had a significant effect on diversity and community structure of Coleoptera at the local level. However, in all data, the effects of site and forest type outweighed the influence of fire. An RDA explained 32% of the variation in community patterns with the effects of fire and environmental parameters. RDA1 scores differed significantly by fire regime, suggesting different species composition of post-fire communities. Hylobius abietis, Byrrhus pilula and Leiodes sp2 were identified as indicator species for fire plots. Protection of beetle refugia is critical for successful habitat recolonization, but is threatened by the post-fire salvage logging practices common in Mongolian forestry.