Aerial photo taken on Sept. 8, 2018 shows solidified sand dunes near the source of the Yarlung Zangbo River in Zhongba County of Xigaze, southwest China's Tibet Autonomous Region. As "clear waters and lush mountains are invaluable assets," China is seeking better coordination between economic and social development and ecological civilization and has delivered visible results. (Xinhua/Purbu Zhaxi)