ACKNOWLEDGEMENTS
We are thankful to Xiu Feng for field sampling. We appreciate the
valuable comments and suggestions from Professor Yunshun Chen and Dr.
Juan Tao. This project was
financially supported by the Strategic Priority Research Program of the
Chinese Academy of Sciences (Grant no. XDB31040101), the National
Natural Science Foundation of China (Grant no. 31572248), and the Second
Tibetan Plateau Scientific Expedition Program.