Abstract: Island-like swamp forest is a unique ecosystem in the eastern Daxing’anling Mountains. Pitfall trap method was used to investigate ground-dwelling arthropod community and habitat characteristics. We analyzed the response of ground-dwelling arthropod community beta diversity to microhabitat characteristics in three typical island-like swamp forests, namely, pure larch forest (Larix gmelinii), pure birch forest (Betula platyphylla), and larch and birch mixed forest. A total of 544 arthropods, belonging to 5 classes, 14 orders, 67 families and 61 genera, were collected. The ground-dwelling arthropod communities were mainly dominated by Coleoptera, Diptera larvae, Hymenoptera, Aranea, and Collembola. Among them, the individual abundance and taxa (order) richness was the highest in the birch pure forest and the lowest in the larch pure forest. There were no significant differences in total beta diversity (β_sor) and species turnover (β_sim) and species nestedness (β_nes) components of ground-dwelling arthropod community in the three habitats, but there were differences in β_sim and β_nes components in the same taxa (P<0.05). The β_sim/β_sor ratio was greater than 50%, indicating that changes in ground-dwelling arthropod community diversity in the island-like swamp forests were mainly affected by species turnover, and the taxa with greater abundance had a greater impact on beta diversity. The diversity of ground-dwelling arthropod community was positively correlated with surface temperature and moisture (r²=0.120-0.128, P<0.01), major soil chemical properties (r²=0.229-0.230, P<0.01), and litter layer thickness (r²=0.148, P<0.01). Surface temperature and moisture, main soil chemical properties and vegetation characteristics together explained 11.03% of the variation of ground-dwelling arthropod community. However, 88.97% of the variation was not explained. Our results suggested that habitat patch heterogeneity caused by soil over-wetting and over-nutrient directly affected the habitat selection preference of ground-dwelling arthropods in the island-like swamp forests and had a complex effect on the maintenance of beta diversity.

Key words: community composition, coexistence pattern, soil physicochemical property, redundancy analysis, Daxing’anling Mountains