2.1 Study sites
We conducted this study in Shaanxi Foping National Nature Reserve (Figure 1), which is located in the Qinling Mountains, with a geographical range between 107°41′ and 107°55′ E and 33°33′ and 33°46′ N. The total area is about 293 km2 and the elevation range is from 980 to 2904 m. In The Fourth National Survey Report on the Giant Panda, there were about 67 wild pandas in the reserve. There are six conservation stations in the reserve, namely Liangfengya, Sanguanmiao, Xihe, Daguping, Longtanzi and Yueba. Among them, Sanguanmiao and Xihe are the core areas of the reserve, which are rich in flora and fauna. In addition to the giant panda, there are also a wide range of national key protected animals such as the takin (Budorcas taxicolor ), forest musk deer (Moschus berezovskii ), leopard (Panthera pardus ) and so on.