Eco-systems in upper reaches of Yangtze River protected in China's Sichuan

This aerial photo taken on April 17, 2018 shows trees in Qingchuan County of Guangyuan, southwest China's Sichuan Province. In recent years, authorities in Sichuan have carried out a series of ecological projects to protect eco-systems in the upper reaches of the Yangtze River. (Xinhua/Xue Yubin)