这是青藏铁路唐古拉山附近“以桥代路”的路段（6月22日摄）。被称为“高原净土”的青藏高原是长江、黄河、澜沧江等5大水系的发源地，也是亚洲重要的水源涵养地和气候启动区。青藏铁路通车10年来，一直采用我国业界最严格的环保标准运营。新华社记者 吴刚 摄
Photo taken on June 22, 2016 shows the section of the Qinghai-Tibet railway near the Tanggula Mountains, northwest China's Qinghai Province. The 1,956-kilometer-long Qinghai-Tibet railway, the world's highest altitude train line, has been put into service for 10 years. It links Lhasa, capital of southwest China's Tibet Autonomous Region, and Xining, capital of Qinghai Province in northwest China. [Photo: Xinhua]