Abstract: A proposed natural gas pipeline and accompanying road from southern Siberia to China would destroy the ecology of a plateau that is internationally recognized for its abundance of rare and endangered species, warn environmentalists meeting here this week. Known as the Ukok Plateau, this area near the intersection of Mongolia, China, Russia and Kazakhstan provides a critical habitat for one of the least studied predators in the world, the snow leopard, and many other endangered species including the argali mountain sheep, the black stork and the steppe eagle.