关键词: 鸟类多样性, 群落结构, 空间分布, MaxEnt模型, 潜在生境分布, 热点区域, 成都市

Abstract:

【Objective】This study aims to explore the structural composition and spatial distribution patterns of bird communities in Chengdu, Sichuan, China, analyze the differences in bird diversity across various habitats and seasons, and identify bird hotspots to provide a basis for bird diversity protection in Chengdu and similar areas.【Method】In 2020, a survey of bird diversity was conducted across different seasons in 20 administrative districts of Chengdu using the line transect method and the sampling point methods. Species richness, Shannon-Wiener diversity index, Simpson index, Pielou evenness index, and community similarity coefficient were calculated to analyze bird diversity in Chengdu. Additionally, 41 key bird species were selected and categorized into raptorial birds, terrestrial birds, natatorial birds, and wading birds based on their ecological habits. The MaxEnt model was used to predict the potential habitats of key birds and identify bird biodiversity hotspots in Chengdu.【Result】A total of 261 bird species across 17 Orders and 62 Families were identified, including one species under national first-class key protection and 29 species under national second-class key protection. Among these, there are 99 species of resident birds, 61 species of summer migratory birds, 60 species of winter migratory birds, and 41 species of transient birds. The number of bird species and individuals, the Shannon-Wiener diversity index, the Simpson index, and the Pielou evenness index were highest in winter, followed by spring, autumn, and summer. Among the six habitats studied, forests (200 species) and wetlands (169 species) had the highest bird species counts. Urban land and wetlands had the highest number of individual birds and population sizes. Forest habitats exhibited the highest Shannon-Wiener diversity index and Simpson index, while urban land had the highest evenness index. The MaxEnt model predictions showed that the distribution of raptorial birds was significantly influenced by land cover type, distance from lakes, and distance from forests. Terrestrial birds distribution was largely affected by distance from forests, altitude, and settlement density. The distribution of waterbirds, including natatorial birds and wading birds, was heavily influenced by land cover type and distance from lakes. Chengdu’s bird diversity hotspots are primarily located in nature reserves, the Longmen Mountain Range, Chaoyang Lake, Longquan Mountain Forest Park, Sancha Lake, Xinglong Lake, Qinglonghu Wetland Park, and along the Minjiang and Tuojiang Rivers.【Conclusion】The rich bird diversity in Chengdu is closely linked to its natural environment, characterized by extensive forest areas, high spatial heterogeneity, and abundant food sources, making it a crucial habitat for birds. Although wetlands comprise only about 2% of the city’s land area, they rank second to forests in bird richness and should be a focal point in future bird biodiversity conservation efforts.

Key words: bird diversity, community structure, spatial distribution, MaxEnt model, potential habitat distribution, hotspot areas, Chengdu City