Xu Zhiqiang, 68, carries water to go through a self-made tunnel, preparing to irrigate trees planted on mountain in Zhangchuan Village of Tongwei County, northwest China's Gansu Province, Aug. 23, 2016. Xu Zhiqiang and his twin brother Xu Zhigang have spent 48 years voluntarily planting trees on barren hills on the Loess Plateau. More than 350 mu (23 hectares) of barren land have turned green with their plantation of over 80,000 trees and flowers. The brothers' efforts not only help create natural beauty but also improve local ecological environment. (Xinhua/Guo Gang)