Ecological change on the Tibetan Plateau

The Tibetan Plateau is the highest physiographic unit regarding average elevation globally. In recent history, the ecosystem structure and function of the Tibetan Plateau, and population size and composition of the dominant species have shown profound changes due to the dual effect of climatic change and human activities. Studies during recent decades on this ecosystem showed that the green-up date of vegetation has advanced resulting in an extended growing period. Generally, the vegetation on the Plateau has improved, but with some local areas becoming degraded. Climatic warming has been a key factor responsible for the positive ecosystem change; however, this effect has been varied, especially the spatiotemporal changes of precipitation, which resulted in large changes of vegetation growth in arid and semi-arid regions. In drought years, the dual effect of climatic change and human activities caused the severe degradation of grasslands, particularly in the western region. However, with the implementation of a constructive project to protect the security of the ecological barrier on the Tibetan Plateau, the degradation of alpine ecosystems has been reduced, and the overexploitation of rare plant resources (e.g., Cordyceps spp., Saussurea spp., Picrorhiza scrophulariiflora) and poaching of wild animals (e.g., yak, Tibetan antelope, and Tibetan wild ass) have decreased, and their populations are recovering. The uplift of the Tibetan Plateau has affected its climate and environment and those of the adjacent areas. Future studies should consider the impact of global change on the Tibetan Plateau, and monitor the changes in ecosystem structure and function through field investigations and the application of remote sensing technology. Further implementation of large-scale ecological engineering to improve the ability of local residents to respond to global change on the Tibetan Plateau is necessary.