Shan Upland

(also Shan Plateau), an upland region in eastern Burma that extends into China (where it is called the Yünnan Plateau), Laos, and Thailand.

In the western part of the Shan Upland, high rolling plains and flat-topped mountain masses alternate with intermontane basins. In the east, mountain ranges with elevations of 2,500–2,600 m are dissected by the deep gorges of various rivers, notably the Salween and Mekong. The Shan Upland, which is composed primarily of gneisses, schists, quartzes, and limestones, exhibits numerous karst phenomena.

The upland has a subequatorial monsoon climate, with a mean January temperature of 18°–24°C and a mean July temperature of about 30°C. Annual precipitation is 1,300–1,700 mm, with more than 2,000 mm on the windward mountain slopes. Most of the precipitation falls in the summer. The rivers, which have many rapids, are a valuable source of hydroelectric power. They are used for timber flotation and, in some cases, irrigation. The largest of the area’s numerous lakes is Lake Inle.

Alpine evergreen and deciduous forests of teak, sal, magnolia, laurel, and bamboo give way to coniferous forests as elevations increase. Savannah vegetation grows in those areas of the Shan Upland that are relatively arid.