Qinghai or Tsinghai (both: chĭngˈhĪˈ) [key], province (2010 pop. 5,626,722), c.279,000 sq mi (722,797 sq km), W China. Xining is the capital. Qinghai lies in the Tibetan highlands at an average elevation of 9,800 ft (3,000 m) and is mainly a high, desolate plateau. The central region has the vast, swampy Qaidam [Mongolian, = salt marshes] basin, and in the northeast there is the large Qinghai Hu or Koko Nor [Chinese and Mongolian, = blue sea] salt lake for which the province is named; it is the largest lake in China. In the precipitous mountain gorges of the south rise some of E Asia's greatest rivers; the Huang He (Yellow), the Chang, and the Mekong.
The chief economic area and the most densely settled part of the province is in the NE around Xining; there coal is mined and grain and potatoes are grown. Extensive irrigation and the use of early-ripening spring wheat increased production in the late 20th cent. Ethnic Chinese (from China proper) and Chinese Muslims predominate in this region. The south is inhabited by Tibetans who live a precarious existence based on stock herding and marginal farming. Stock breeding is also important; Qinghai horses are world famous. The Qaidam basin was once peopled only by a scattered population of Tibetan, Kazakh, and Mongol herders, but from the 1950s to the 1970s there was an influx of Chinese to work in the mineral extraction industries there (oil, iron ore, salt, lithium, boron, zinc, potash, magnesium, and lead). Salt is so abundant that it is used for building blocks and for road pavement. Heavy industry, utilizing the province's store of mineral resources, has increased steadily since the 1950s. Thousands of miles of highways have been constructed to link Xining and the Qaidam basin with adjoining provinces; there are rail links between Xining and Lanzhou, in Gansu prov., and Lhasa, in Tibet. The noted Kumbum lamasery is SW of Xining.
Historically a part of Tibet, the Qinghai region passed to the Mongol overlords of China in the 14th cent., when it became part of Gansu. It came under Chinese (Ch'ing dynasty) control after 1724 and was administered from Xining as the Koko Nor territory. Over the centuries Chinese settlers have proceeded up the Xining and Huang He rivers from Lanzhou, penetrating deeply into ethnic Tibetan territory in the northeast. In 1928, Qinghai became a province of China. The Communist government established autonomous districts for the Tibetan, Chinese Muslim, Kazakh, and Mongol minorities. In 2010 an earthquake caused severe destruction in parts of S Qinghai; some 2,700 people were killed.