Distribution and Influences on Butterfly Diversity in Urban Park Green Spaces: A Case Study of Harbin, China

With the acceleration of urbanization, urban parks play a critical role in protecting biodiversity and maintaining ecosystem stability. As environmental indicator species, butterflies exhibit high sensitivity to environmental changes and anthropogenic disturbances, making them ideal subjects for studying urbanization's impacts on biodiversity. This study focuses on the effects of spatial heterogeneity in the surrounding matrix and its interaction with park resources on butterfly diversity in urban parks. Using Harbin City in Heilongjiang Province, northeastern China, as the study area, we collected data on butterfly species richness and park characteristics from 44 urban parks. Spatial heterogeneity was quantified through landscape metrics across eight spatial scales (100-2500 m), and generalized linear mixed models were employed to analyze butterfly community responses to park characteristics and landscape patterns (composition and configuration) at multiple spatial scales. The results identified 38 butterfly species and 12,885 individuals in Harbin's urban area, with significantly higher species richness in urban fringe zones compared to the city center. Heterogeneity indicators across different spatial scales showed complex relationships with butterfly communities. Butterfly community structure and composition demonstrated highest sensitivity to landscape heterogeneity at 100 and 200 m scales, with optimal model explanatory power for richness, abundance, and diversity being 67.8%, 81.1%, and 38.8% respectively. Key predictors exhibited hierarchical differentiation: richness was primarily positively driven by flowering plant richness and distance from the city center, while being significantly suppressed by park perimeter-area ratio and built-up land patch proportion; abundance was core-driven by flowering plant richness, patch quantity, and patch proximity; diversity relied on the synergistic effects of grassland patch proportion and plant diversity. This study confirms that under intensive urbanization, coordinated management of intra-park habitat resources and surrounding landscape heterogeneity can significantly mitigate urban development-induced butterfly diversity decline, providing a multi-scale planning framework for establishing a "patch-matrix" linkage ecological regulation system in high-latitude cold-region cities.