关键词: 尺蛾科, 群落多样性, 大别山, 吴家山, 时空动态

Abstract

Aims: Geometridae is the second largest family of Lepidoptera, with some species causing severe damage to agricultural and forestry production in the Dabie Mountains. However, research on the composition of the Geometridae community in this region is relatively scarce, and the spatiotemporal dynamics of its variation remain unclear. This study aims to focus on three core scientific questions: the composition of the geometrid community in the Dabie Mountains; the spatial distribution pattern of the geometrid community in the Dabie Mountains and Wujia Mountain; the temporal dynamics of the geometrid community in Wujia Mountain and the significance of its monthly variation patterns. 

Methods: From 2020 to 2023, we conducted 109 surveys at 63 sampling sites in the Dabie Mountains, collecting 8,517 geometrid specimens. Species were identified based on adult morphology and dissection of male and female genitalia. Sampling completeness was assessed using species accumulation curves and abundance-base coverage estimator (ACE) and incidence-base coverage estimator (ICE). Community structure and spatiotemporal changes were analyzed using species-abundance distributions, the Margalef richness index, the Shannon-Wiener diversity index, the Berger-Parker dominance index and the Pielou evenness index. In addition, this study took Wujia Mountain in the hinterland of the Dabie Mountains as a representative area, and selected five different monitoring sites across low, medium, and high altitude gradients. The survey of geometrids was conducted from April to October, and the relevant diversity index statistics and calculation results were the same as above. 

Results: A total of 8,517 specimens were obtained in this study. After identification, it was found that the Geometridae community in the Dabie Mountains consisted of 5 subfamilies, 163 genera, and 266 species, including one newly recorded species in China, Amoebotricha grataria (Leech, 1891). In terms of community composition, Ennominae was the dominant group, with the species Idaea paraula (Prout, 1914) accounting for 14.94% of individuals, making it the dominant species in the Dabie Mountains, while the number of rare species accounting for less than 1% of individuals reached as many as 246 species, reflecting the high complexity of the community. Combining the information from the collection sites, areas with high diversity of Geometridae were concentrated in the hinterland of the Dabie Mountains at medium altitude with less human disturbance, and the geometrid community was relatively stable. In contrast, outbreaks of dominant species were more likely to occur in the areas with lower altitude. The geometrid community in Wujia Mountain exhibited marked spatiotemporal variation. In the temporal dimension, May to July was the peak period for the geometrid community in Wujia Mountain. After August, the number of species and Shannon-Wiener diversity indexes generally decreased, but there was a surge in individual numbers at some sites. For example, in September, the individual numbers at Dianzhan and Shigusi both exploded. In the spatial dimension, the species richness and abundance led to mid-altitudinal peaks on altitudinal gradients, with the altitude of peak occurrence ranging from 713 to 1168 m for the number of species and from 700 to 1000 m for the species richness. 

Conclusion: Based on a comprehensive survey in the Dabie Mountains and Wujia Mountain, this study provides a scientific basis for research on geometride diversity in the Dabie Mountains and for the precise monitoring and sustainable management of geometrid pests, which can be helpful to both agricultural productivity and long-term ecosystem stability in the area.

Key words: Geometridae, community diversity, Dabie Mountains, Wujia Mountain, spatiotemporal dynamics