An aerial drone photo taken on March 21, 2025 shows the Tuotuo River in the source region of the Yangtze River in northwest China's Qinghai Province. (Xinhua/Qi Zhiyue)

An aerial drone photo taken on March 21, 2025 shows the Tuotuo River in the source region of the Yangtze River in northwest China's Qinghai Province. (Xinhua/Qi Zhiyue)

An aerial drone photo taken on March 22, 2025 shows the Qumar River in the source region of the Yangtze River in northwest China's Qinghai Province. (Xinhua/Qi Zhiyue)

An aerial drone photo taken on March 21, 2025 shows the Tuotuo River in the source region of the Yangtze River in northwest China's Qinghai Province. (Xinhua/Wang Jinjin)

An aerial drone photo taken on March 20, 2025 shows the Qumar River in the source region of the Yangtze River in northwest China's Qinghai Province. (Xinhua/Qi Zhiyue)