Lu Zhang, Tian Dong, Weihua Xu, Zhiyun Ouyang
Wildlife Research 42 (3), 266-279, (15 July 2015) https://doi.org/10.1071/WR14124
Context . Traffic network construction is an essential method for enhancing the effectiveness of economic activities, but it can have various negative impacts on rare wildlife. In China, the rate of road construction has increased by over 300% during the past decade; however, the resulting fragmentation of rare habitats at a national scale remains uncertain.
Aims . This study mainly aimed to evaluate the impacts of road and railway networks on the fragmentation of habitats of endangered species in China. Another aim is to identify the key areas and road sections where improvements to habitat connectivity and integrity are urgently required.
Methods . We documented habitat information for 21 indicator species on the basis of two comprehensive datasets and over 120 previous studies. We combined this information to simulate the habitats of all these species by integrating a conceptual model and expert knowledge. We calculated the rates of change on the basis of three geometric habitat patterns for each species in traffic-clearing scenarios and road- and railway-overlay scenarios. An optimal algorithm, the core-area zonation cell-removal rule, was used to identify rare habitats affected by severe traffic stress.
Key results . According to our analysis, we ranked the road density in the habitats of all species as a straightforward evaluation of transportation stress. Among the different species considered, snow leopard (Panthera uncia), Cabot’s tragopan (Tragopan caboti) and Przewalski’s gazelle (Procapra przewalskii) appeared to be affected most severely by road-induced fragmentation. In addition, we classified five patterns of habitat fragmentation among species to facilitate wildlife management. On the basis of the trade-off between road density and conservation value per unit, we identified 17 unit sets as key traffic-affected areas, including 40 highways, 62 national roads and 51 railway sections.
Conclusions . Our results suggested that assessing the distributions of several key species can be effective in evaluating the impacts of roads on rare-wildlife habitats in China. Our results also indicated that the habitats of narrowly distributed species, such as Chinese alligator and Sichuan partridge, have high traffic densities, but core habitat degradation is even more serious for the habitats of species with higher intrinsic mobility or greater area requirements. Finally, we suggest that future conservation programs and restoration efforts should concentrate on roads or railway sections in the key areas that we identified.
Implications . In the present study, we obtained spatially explicit findings related to the maintenance of rare wildlife in a region where wildlife-protection information is lacking. Our site-selection results can be used to allocate highly limited conservation resources in a more efficient and effective manner, to facilitate wildlife protection in this region.