关键词: 受胁鸟类栖息地, 生物多样性保护, 保护潜力区, 乡村生境区, 湿地, 城市绿地, 北京

Abstract

Aims: Protecting biodiversity in highly populated metropolises is an important effort for global biodiversity conservation. Beijing is home not only to a large human population, but also large biodiversity clusters. Three levels of conservation management have been administratively delimited: the nature reserves, the ecological red line, and the construction control line. These groups, as a whole, represent the potential areas for conservation (PAC). We intend to explore the methods to conserve the endangered species of birds in Beijing.
Methods: Here, we explored the coverage of 30 recently recorded threatened bird species based on the existing PAC. Based on each selected species’ habitat preferences, we calculated the species distribution models and combined it with the land use and land cover map to generate the potential distribution map. We then overlayed those maps to obtain the overall distribution pattern in Beijing for the selected bird species. This distribution pattern enabled us to calculate the species richness at any interested sites within our study area.
Results: Based on the species richness map, we ranked all habitats as four grades based on the number of endangered species present. We also classified urban, rural, and natural areas based on the intensity of urban land use and human activities. This allowed us to calculate the coverage of our ranked key habitats and different urbanization gradient by each of the three PAC groups. We had two major findings. First, 95.64% of grade I and 86.32% of grade II habitats are within the rural areas, whereas merely 0.69% of the rural areas are covered by nature reserves and 15.15% by the ecological protection red line. Second, the defined key habitats ranked as grade I and II but not yet under the umbrella of either the nature reserves or the ecological protection red line are mainly wetlands (waterbodies and marshlands), high coverage grasslands, farmlands, and some large-scale green patches in urban areas with large bodies of water. Based on these results, we offer the following suggestions to help with conservation: (1) preservation of wetlands and the high coverage grasslands surrounding the urban cores efficiently; (2) maintaining the scale of basic farmland and food crop planted; (3) including all bodies of water, marshlands, and high coverage grasslands alongside rivers in ecological protection red line area; (4) delimiting biodiversity conservation zones in large urban greenspaces such as major urban parks; and (5) optimizing the structure of woodland communities in rural and urban areas to satisfy the habitat needs of some specialist species.
Conclusion: Implementing those conservation practices will provide Beijing with more diverse avian communities. These efforts could be a good case for biodiversity conservation in other major cities of China to follow.

Key words: habitats of threatened birds, biodiversity conservation, potential areas for conservation, rural habitat, wetland, urban green spaces, metropolitan Beijing