Photo taken on Sept 28, 2015 shows an aerial view of Dujiangyan Irrigation System in Dujiangyan, Southwest China’s Sichuan province. [Photo/Xinhua]

Photo taken on Sept 28, 2015 shows an aerial view of Dujiangyan Irrigation System in Dujiangyan, Southwest China’s Sichuan province. [Photo/Xinhua]

Photo taken on Sept 28, 2015 shows a dike of Dujiangyan Irrigation System in Dujiangyan, Southwest China’s Sichuan province. [Photo/Xinhua]