关键词: 步甲, 景观组成, 景观配置, 分类多样性, 功能多样性

Abstract: Afforestation has extensively replaced the original land use types, leading to changes in landscape structure. This study aimed to explore the relationship between carabid beetle diversity and landscape composition and configuration in tree plantations in Ansai, Shaanxi. A total of 20 plots were selected based on the proportions of four types of landscape composition. Carabid beetles were sampled, and landscape metrics were calculated at five scales (100-1000 m) in the circular landscapes around the plots. We analyzed the relationships of landscape metrics with carabid beetle abundance, richness, Shannon diversity, functional richness, functional divergence, and Rao’s quadratic entropy. We found no significant differences in carabid beetle diversity among the different plot types. At all scales, the total patch area of woodland was not significantly correlated with carabid beetle abundance and richness. However, the total patch area of woodland and farmland positively influenced Shannon diversity and functional diversity of carabid beetles. The total patch area of shrubland negatively affected abundance and positively affected diversity. The woodland patch shape index showed a negative correlation with carabid beetle abundance and functional diversity at multiple scales. Woodland patch connectivity promoted the abundance of dominant species. The connectivity of farmland and grassland patches had a positive effect on Shannon diversity at the 250 m scale, while the influence direction of grassland patch connectivity reversed at the 750 m scale. Based on the goal of enhancing landscape heterogeneity and biodiversity in tree plantations, the following conservation strategies are proposed: (1) Future land management plans should include a welldesigned landscape composition scheme. Woodland area should be maintained or increased to improve the heterogeneity of forest stand structure, and planted shrublands should also be considered and managed. (2) Complex woodland patch shapes should be modified to reduce edge areas, with vegetati on structure mimicking natural edges, and human disturbances near woodland edges should be controlled. (3) Measures to enhance the connectivity of woodland patches should be considered to facilitate dispersal.

Key words: carabid beetle, landscape composition, landscape configuration, taxonomic diversity, functional diversity