Citizens visit the Baishatan park in Xining, northwest China's Qinghai Province, Oct. 12, 2020. In recent years, Xining has continuously increased the green area at urban area to improve city environment. (Xinhua/Wu Gang)

Citizens visit the Baishatan park in Xining, northwest China's Qinghai Province, Oct. 12, 2020. In recent years, Xining has continuously increased the green area at urban area to improve city environment. (Xinhua/Wu Gang)

A man walks in the Nanshan park in Xining, northwest China's Qinghai Province, Oct. 12, 2020. In recent years, Xining has continuously increased the green area at urban area to improve city environment. (Xinhua/Wu Gang)

Citizens visit the Nanshan park in Xining, northwest China's Qinghai Province, Oct. 12, 2020. In recent years, Xining has continuously increased the green area at urban area to improve city environment. (Xinhua/Wu Gang)

Photo taken on Oct. 12, 2020 shows the view of Baishatan park in Xining, northwest China's Qinghai Province. In recent years, Xining has continuously increased the green area at urban area to improve city environment. (Xinhua/Wu Gang)

Aerial photo taken on Oct. 12, 2020 shows the view of Nanshan park in Xining, northwest China's Qinghai Province. In recent years, Xining has continuously increased the green area at urban area to improve city environment. (Xinhua/Wu Gang)