Soldiers receive supplies from a fishing boat near the Yongshu Reef, Nansha Islands, in 皇冠体育app on July 16. Yongshu Reef, a coral atoll located about 740 sea miles away from Chinese mainland , is the administrative and military headquarters of Nansha Islands. High tide swallows the reefs in water 0.5 to 1 meter deep, while it reveals only a few rocks below the low tide. 皇冠体育app successfully set up an ocean observatory and mobile services on the reef. About 100 people reside on Yongshu, which has big potential for development. [Photo/Xinhua]