**2. Materials and Methods**

#### *2.1. Study Area*

Qinghai Province is located in the northeast of the Qinghai-Tibet Plateau (36◦31 –39◦19 N latitude, 89◦35 –103◦04 E longitude) (Figure 1). The region has a plateau continental climate, with an average annual temperature of 2–9 ◦C and an annual rainfall of 250–550 mm. Qinghai is the birthplace of the Yellow, Yangtze, and Lancang rivers and one of the most important ecological protection barriers in China. At present, due to the fragile ecological environment restricted by topography and resources, the exploitable land resources in Qinghai province are scarce and the land use structure is simple [40]. The above situation has led to the imbalance of population distribution and economic development layout in the

province at different degrees, and the issues related to ecological environment protection have also become prominent.

**Figure 1.** Location of Qinghai Province, China.
