Qinghai Hu Lake (36N, 99E China)

This is a photograph of Qinghai Hu, the largest saltwater lake in China. The lake sits about 3205 m (10515 ft) above sea level in the highlands of the Tibetan Plateau. This is a semi-arid region, and although there are rivers flowing into Qinghai Hu, it has no outlet. Because of this, dissolved minerals carried in are left behind by evaporation, and become more concentrated, which has caused the lake to become salty. The lake has an area of 4635 sq. km (1800 sq. mi) and is about 350 km (220 mi) in circumference. Despite its size, the lake is relatively shallow, which enables it to freeze. This image of the lake was actually taken while it was frozen over, leading to its interesting surface features. The shapes and shades of the ice show how parts of the lake froze at different times, how some parts of the ice are thicker than others.

A noted feature and popular attraction of Qinghai Hu is Bird Island, a peninsula in the westernmost part of the lake (towards the top of the photograph). Despite its name, Bird Island is no longer an island, but has become a peninsula due to receding water levels. However, it is still (as the name suggests) a breeding ground for many different types of birds, including the extremely rare black-necked cranes.

Qinghai Province, which takes its name from this lake, is also home to the headwaters of the Yangtze River and the Yellow River. Qinghai is historically one of the poorest regions in China due to its severe weather and high altitude. It is home to only about 4.5 million people, only about one-third of whom are ethnically Chinese, the rest being Mongol, Tibetan, and Kazakh; with an area of 724000 sq. km (280000 sq. mi), it has the lowest average population density in China. However, most of the population lives in the valleys of the easternmost part of the province. The rest of the region consists mostly of nomadic herders.