Abstract: It has been noted that insect community is a powerful indicator of forest discover and succession. We examined the changes in species diversity and faunal composition of insect along a successional gradient of conifer and broad-leaved mixed forests in Changbai Mountain in this study. Insect community of three habitats, viz. secondary birch forest （SBF）, secondary conifer and broad-leaved mixed forest (SCBF), and original broad-leaved Korean pine forest (OBPF), from the early successional stage to mature forest understory were investigated by using sweeping nets, light traps and pitfall traps. The results showed that a total of 8 183 individuals representing 699 species in 362 orders were recorded. The dominant species were of Lepidoptera and Coleoptera. SCBF had the highest number of individuals and OBPF had the highest number of species, but the number of species and individuals between the successional habitats did not differ significantly. The Fisher’s α index values of SCBF and OBPF were significantly greater than that of SBF, and the diversity at the family level was not significantly different between the three habitats. Insect diversity increased following the herb diversity along the successional habitats. Because of different feeding habits and habitat preference, the diversity of Lepidoptera increased along the successional habitats, while that of Coleoptera decreased, which was similar to that found in previously reported studies.

Key words: Insects, community succession, species diversity, secondary birch forest (SBF), secondary conifer and broad-leaved mixed forest (SCBF), original broad-leaved Korean pine forest (OBPF), Changbai Mountain