Study on the community structure and population dynamics of aerial insects in Nanyang City of Henan Province

In order to explore the community structure of airborne insect species in Nanyang City of Henan Province, the insect species and dynamics were monitored by searchlight trap at night from 2021 to 2023. A total of 112 species of insects, belong to 42 families, 10 orders, were trapped, with the most species belonging to Lepidoptera (13 families, 71 species), followed by Coleoptera (10 families, 17 species) and Hemiptera (8 families, 12 species). Among the 42 families, the dominant families were Noctuidae (31 species), followed by Sphindidae (10 species), Borellidae (6 species). There were significant inter-annual differences in the composition of the insect community structure, with the permanent species being Helicoverpa armigera, Laodelphax striatellus, Agrotis segetum and Manduca sexta in 2021, H. armigera and L. striatellus in both 2022 and 2023. Ostrinia furnacalis, Spodoptera exigua, Theretra japonica, Anomala corpulenta, Holotrichia parallela, Gryllotalpa orientalis and Cryllus testaceus were common species.The Shannon-Wiener index and evenness index were highest in 2021 (Shannon-Wiener index = 2.0709, evenness index = 0.4406), followed by 2023 (Shannon-Wiener index = 0.7169, evenness index = 0.1544), and lowest in 2022 (Shannon-Wiener index = 0.6507, evenness index = 0.1419). A total of 149606 insects were trapped over the three years, with the highest trap-catching amount in 2022 (60737 individuals), which was 1.3 and 1.4 times of 2021 and 2023, respectively. H. armigera was the dominant species locally, accounting for 37.79% of the total trap-catching amount of over the three years. Other dominant species included C. maculatus (20.58%), A. corpulenta (10.91%), S. frugiperda (7.82%), and O. nubilalis (3.55%). This study provides a useful contribution to understanding the insect community structure and population dynamics in Nanyang and provides guidance for local pest monitoring and control efforts.