Photo taken on Dec. 15, 2020 shows a view of an urban wetland park in Handan City of north China's Hebei Province. Authorities in Handan City have stepped up in recent years to improve ecological environment across the entire drainage basin of Fuyang River. (Xinhua/Wang Xiao)

Photo taken on Dec. 15, 2020 shows a view of Fuyang River in Cixian County, Handan City of north China's Hebei Province. Authorities in Handan City have stepped up in recent years to improve ecological environment across the entire drainage basin of Fuyang River. (Xinhua/Wang Xiao)

Photo taken on Dec. 15, 2020 shows a view of Fuyang River in Cixian County, Handan City of north China's Hebei Province. Authorities in Handan City have stepped up in recent years to improve ecological environment across the entire drainage basin of Fuyang River. (Xinhua/Wang Xiao)

Tourists visit the Yiquan Lake Wetland Park in Cixian County, Handan City of north China's Hebei Province, Dec. 15, 2020. Authorities in Handan City have stepped up in recent years to improve ecological environment across the entire drainage basin of Fuyang River. (Xinhua/Wang Xiao)

Aerial photo taken on Dec. 15, 2020 shows a view of Fuyang River in Cixian County, Handan City of north China's Hebei Province. Authorities in Handan City have stepped up in recent years to improve ecological environment across the entire drainage basin of Fuyang River. (Xinhua/Wang Xiao)