Photo taken on Nov. 6, 2019 shows Shudu lake at Pudacuo National Park in Tibetan Autonomous Prefecture of Deqen in southwest China's Yunnan Province. (Photos: Xinhua)

Aerial photo taken on Nov. 11, 2019 shows the scenery of Baishuitai scenic spot in Tibetan Autonomous Prefecture of Deqen in southwest China's Yunnan Province.

Blacknecked cranes rest at the Napahai Nature Reserve in Tibetan Autonomous Prefecture of Deqen in southwest China's Yunnan Province, Nov. 10, 2019.

Photo taken on Nov. 8, 2019 shows the sunrise scenery at Meili Snow Mountains in Tibetan Autonomous Prefecture of Deqen in southwest China's Yunnan Province.

Aerial photo taken on Nov. 6, 2019 shows the scenery of Pudacuo National Park in Tibetan Autonomous Prefecture of Deqen in southwest China's Yunnan Province.

Photo taken on Nov. 10, 2019 shows the scenery of Napahai Nature Reserve in Tibetan Autonomous Prefecture of Deqen in southwest China's Yunnan Province.