Abstract: Landuse change and habitat loss are two top threats to biodiversity. Tropical forest is a hotspot for biodiversity but threatened by forest fragmentation. To explore the effects of forest fragmentation on arthropod diversity, we used metabarcoding to investigate the composition and diversity of arthropods underneath nine forest fragments in a rubber landscape matrix in Nabanhe Nature Reserve (Xishuangbanna, SW China). A total of 347 OTUs of 18 arthropod taxa were collected from nine forest fragments. There were 225 OTUs in large forest patches (≥50 hm² in size), 113 OTUs in medium forest patches (10-50 hm²), and 139 OTUs in the small forest patches (≤10 hm²), respectively. Forest patch size significantly affected arthropod richness, with the responses of different arthropod communities to forest patch sizes being varied. The beta diversity of arthropods in larger forest patches was significantly lower than that in smaller patches, whereas there was no significant difference in beta diversity of arthropods between the medium and small forest patches. Our results suggested that large forest patches in tropical regions had positive impacts on both composition and diversity of arthropod community, while small forest patches also deserves to be conserved.

Key words: aboveground biomass, spatial variability, species diversity, plant community, environmental factor