Swans fly over the Qinghai Lake in northwest China's Qinghai Province, Dec. 13, 2012. The Qinghai Lake, China's largest inland salt water lake, presents a beautiful scenery in winter. [Photo/Xinhua]

An amateur photographer takes photos of the sunrise scenery on the Bird Island of Qinghai Lake in northwest China's Qinghai Province on Dec. 12, 2012. The Qinghai Lake, China's largest inland salt water lake, presents a beautiful scenery in winter. [Photo/Xinhua]

Photo taken on Dec. 12, 2012 shows the sunrise scenery of the Qinghai Lake in northwest China's Qinghai Province. The Qinghai Lake, China's largest inland salt water lake, presents a beautiful scenery in winter. [Photo/Xinhua]

A tourist jumps on a bridge on the Bird Island of the Qinghai Lake in northwest China's Qinghai Province, Dec. 13, 2012. The Qinghai Lake, China's largest inland salt water lake, presents a beautiful scenery in winter. [Photo/Xinhua]