Photo taken on May 28, 2019 shows the scenery of Shizuizi Reservoir in Zaozhuang, east China's Shandong Province. Shandong has implemented the new mentality of green development to make contributions to sustainable development in recent years. (Xinhua/Li Zongxian)

Aerial photo taken on April 26, 2019 shows the scenery of Baima River Wetland Park in Tancheng County of Linyi City, east China's Shandong Province. Shandong has implemented the new mentality of green development to make contributions to sustainable development in recent years. (Xinhua/Fang Dehua)

Aerial photo shows a staff member walking at the ecological-themed forest park in Zouping, east China's Shandong Province, on May 28, 2019. Shandong has implemented the new mentality of green development to make contributions to sustainable development in recent years. (Xinhua/Dong Naide)

Photo taken on June 2, 2019 shows part of the old town in Zaozhuang , east China's Shandong Province. Shandong has implemented the new mentality of green development to make contributions to sustainable development in recent years. (Xinhua/Sun Zhongzhe)

Aerial photo taken on May 24, 2019 shows farmland in Xinzhuang Town of Feixian County in Linyi City, east China's Shandong Province. Shandong has implemented the new mentality of green development to push sustainable development in recent years. (Xinhua/Wu Jiquan)

Tourists are seen at a national mine park in Zaozhuang, east China's Shandong Province, on June 2, 2019. Shandong has implemented the new mentality of green development to make contributions to sustainable development in recent years. (Xinhua/Sun Zhongzhe)

Aerial photo taken on May 22, 2019 shows the view of Xiaofuhe wetland park in Zibo City, east China's Shandong Province. Shandong has implemented the new mentality of green development to make contributions to sustainable development in recent years. (Xinhua/Zhao Shengjian)

A man windsurfs in Yinghua Lake Sports Park in Rongcheng, east China's Shandong Province, on May 29, 2019. Shandong has implemented the new mentality of green development to make contributions to sustainable development in recent years. (Xinhua/Li Xinjun)