Abstract:

Urbanization is one of the main reasons for forest fragmentation in urban systems, which causes threats to biodiversity through both species decline and biotic homogenization. This study aims to reveal the richness, abundance, and diversity of mammals on the fragmented forest patches in urban, suburban and rural areas. Our study helps to provide substantial data for the protection of mammal diversity and land-use planning in urban ecosystems. According to the urban-suburban-rural gradient, we surveyed the diversity of mammals on 13 forest patches in Wuhan from 2019 to 2021 by using literature reviewing and camera-trapping. Taking the patch area, distance to the urban center, isolation, and shape index as patch characteristics of urbanization, we analyzed the relationships between species composition and patch characteristics by using RDA, and examined the relationships between the species diversity and patch characteristics by using linear regression. We recorded 15 forest mammals in total, which belong to 8 orders and 6 families. The dominant species are Racoon dog (Nyctereutes procyonoides), Asian badger (Meles leucurus), Wild boar (Sus scrofa), and Confucian niviventer (Niviventer confucianus). The fauna type is dominated by oriental species. The species composition was positively correlated with distance to the urban center in suburban forest, and negatively correlated with area in urban forest. The species richness (P < 0.01) and Shannon-Wiener diversity index (P < 0.05) were significantly positively correlated with the distance to urban center. There was no significant correlation between species richness and Shannon-Wiener diversity index with isolation and shape index (P > 0.05). Our study showed that the distance to the urban center was the main factor affecting forest mammal diversity in Wuhan. The high speed of urbanization in Wuhan has reduced the mammal diversity. For maintaining and restoring the high diversity of mammals, we recommend that some specific measures should be carried out in urban forest patches to reduce human disturbance and protect natural forests, especially the continuous natural forests in the suburban and rural areas.

Key words: Forest fragmentation, Infrared camera, Urban-suburban-Rural gradient, Isolation, Shape index

摘要：

生境破碎化造成生物多样性降低，尤其是哺乳动物多样性的降低甚至丧失。快速城市化背景下，城市森林斑块成为典型的破碎化生态系统。对城市森林斑块中哺乳动物资源的调查，能够为城市生态系统健康评估和城市景观格局的建设提供依据。2019—2021年，通过实地调查和红外相机拍摄对武汉市13个森林斑块的哺乳动物进行调查，并分析城市化对物种组成群落多样性的影响。本次调查共布设77台相机，相机总工作天数为21 247日，拍摄到野生哺乳动物独立有效照片1 243张，记录野生哺乳动物5目9科15种，主要属于东洋界华中区，其中貉 (Nyctereutes procyonoides)、亚洲狗獾 (Meles leucurus)、野猪 (Sus scrofa)、北社鼠 (Niviventer confucianus) 为常见种。哺乳动物物种丰富度 (P < 0.01)、香农-威纳指数 (P < 0.05) 随距市中心距离增加而显著增加，与斑块隔离度、形状指数则无显著相关 (P > 0.05)，说明距市中心距离是哺乳动物多样性的重要影响因子。此外，近郊、远郊自然森林斑块哺乳动物多样性相对较高，说明城市化对哺乳动物多样性有负面影响。

关键词: 森林斑块化, 红外相机, 城郊梯度, 隔离度, 形状指数