Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Dronla)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Dongjun)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Ziming)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Dongjun)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Dronla)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Dongjun)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Dongjun)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Ziming)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Dongjun)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Dongjun)

Photo taken on Nov. 13, 2015 shows the scenery of Lhalu wetland on the northwest outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region. Lhalu wetland, at an altitude of 3,600 meters, is the highest natural wetland in China. (Xinhua/Liu Ziming)