Flowers are seen in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province, on April 26, 2020. Xixi National Wetland Park, located on the outskirts of Hangzhou, is the first national wetland park in China. The wetland park helps to restore the local ecology and also serves as an eco-education, research and tourism base. (Xinhua/Huang Zongzhi)

Photo taken on Aug. 22, 2020 shows a helium balloon floating in the sky in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province. (Xinhua/Huang Zongzhi)

A boy takes a boat in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province, on Aug. 22, 2020. (Xinhua/Huang Zongzhi)

Tourists take a boat in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province, on Aug. 22, 2020. (Xinhua/Huang Zongzhi)

Flowers are seen in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province, on April 26, 2020. (Xinhua/Huang Zongzhi)

Aerial photo taken on Aug. 22, 2020 shows the scenery of the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province. (Xinhua/Huang Zongzhi)

Aerial photo taken on Aug. 22, 2020 shows boats sailing in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province. (Xinhua/Huang Zongzhi)

Tourists take a boat in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province, on Aug. 22, 2020. (Xinhua/Huang Zongzhi)

Aerial photo taken on Aug. 22, 2020 shows a boat sailing in the Xixi National Wetland Park in Hangzhou, east China's Zhejiang Province. (Xinhua/Huang Zongzhi)