Aerial photo taken on April 18, 2022 shows the scenery of a national wetland park in Zhangye, northwest China's Gansu Province. (Photos: Xinhua/Zhang Zhimin)

Aerial photo taken on April 18, 2022 shows the scenery of a national wetland park in Zhangye, northwest China's Gansu Province.

Aerial photo taken on April 18, 2022 shows the scenery of a national wetland park in Zhangye, northwest China's Gansu Province.

Aerial photo taken on April 18, 2022 shows the scenery of a national wetland park in Zhangye, northwest China's Gansu Province.

Aerial photo taken on April 18, 2022 shows the scenery of a national wetland park in Zhangye, northwest China's Gansu Province.