This photo taken with a mobile phone shows herds of sheep grazing by the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)

This photo taken with a mobile phone shows tourists enjoying scenic beauty of the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)

This photo taken with a mobile phone shows the scenery of the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)

This photo taken with a mobile phone shows brown-headed gulls by the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)

This photo taken with a mobile phone shows the scenery of the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)

This photo taken with a mobile phone shows a brown-headed gull by the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)

This photo taken with a mobile phone shows the scenery of the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)

This photo taken with a mobile phone shows the scenery of the Yamzbog Yumco Lake, southwest China's Tibet Autonomous Region, May 1, 2023. (Xinhua/Shen Hongbing)