Ecological networks in response to climate change and the human footprint in the Yangtze River Delta urban agglomeration, China

Context A continuous increase in human activity and drastic changes in the global climate have aggravated the loss and degree of fragmentation of natural habitats, thereby forcing various species to change their habitats to acquire suitable survival spaces. Objectives To investigate the potential impacts of climate change and human activity on ecological networks. Methods By using the human footprint, and current and future temperature, we analyzed and compared the distribution of ecological sources, corridor patency and climate connectivity within the Yangtze River Delta urban agglomeration area under scenarios with and without corridors and various levels of warming. Results The human footprint significantly influenced the distribution of ecological sources and corridor patency in the study area. A high human footprint index was associated with a high degree of fragmentation and weak corridor patency. In general, the current distribution of ecological sources and climate corridors exhibited a significant north-south disparity. Under all climate change scenarios assessed, the number and areas of ecological sources that achieved climate connectivity by linkage migration were higher than those achieved by adjacent migration, with the numbers for the former being 1.3-2.5 times greater than those for the latter. In addition, the level of warming that can be tolerated with linkage migration is higher than that with adjacent migration (2.8 degrees C vs. 0.8 degrees C). Conclusion Climate connectivity can be better enhanced by constructing corridors than controlling warming, thereby effectively increasing the climate-wise biodiversity conservation potential. Therefore, the determination of priority conservation areas from the aspects of climate change and ecological corridor conservation is recommended.

Automated summary

Human activities and climate change have led to loss and fragmentation of natural habitats, forcing species to change habitats for survival. The study found that human footprint significantly influenced distribution of ecological sources and corridor patency. Building corridors is more effective in enhancing climate connectivity for biodiversity conservation than controlling warming.