On the Asia map, one can find a large slope that spans southward from the Southeast Tibetan Plateau and extends down to the Indo-China Peninsula. Midway on this slope, between 99°58′-101°50′ E and 21°09′-22°36′ N is the Xishuangbanna region, a Dai Ethnic Nationality Autonomous Prefecture of Yunnan Province, China. Historical records showed that the ancestors of the Dai people resided in this region more than 2,000 years ago. In 1180, the chieftain of a Dai tribe conquered other tribes and founded a local Kingdom, which conquered 12 local districts. In the Dai language, “Xishuang” means 12 and “Banna” means districts; hence, “Xishuangbanna” implies the 12 districts that existed historically.
Climatically, Xishuangbanna is best described as having a transition monsoon climate of the tropics and subtropics. The monsoons from the southwest carry large amounts of warm and moist air masses into Xishuangbanna, but with no risk of typhoons. The area is very mountainous, reaching 2,429 meters above sea level (m a. s.l.) to the north, and sloping southward to a low point of 477 m a. s.l. The general topography consists of basins or valleys alternating with hills or mountains. A tropical climate prevails in the basins and low valleys, with a subtropical climate in the mountains and higher hills. Annually, summers are characterized by high temperatures and humidity, whereas winters offer little rain and much heavy fog, and then gentle winds bode spring. The region is free from frost all year round. However, cold currents occasionally intrude in higher elevations, rendering a cool and dry climate in relationship to the tropics of Southeast Asia.
Xishuangbanna is a kingdom of fauna and flora biodiversity. The main vegetation types are tropical rainforests, tropical monsoon forests, and subtropical evergreen broad-leaved forests. According to incomplete statistics, approximately 4,600 species of higher plants have been discovered, of which 80 % belong to tropical and subtropical floral species. There are 343 species of higher plants that have been considered rare species. There is also an extraordinary abundance of fauna in Xishuangbanna, and 758 species of vertebrates have been identified. Of the 108 mammals, 36 species have been listed in the Chinese Fauna Red Book (Xu et al. 1987).
There are 13 ethnic groups with a larger population recognized in Xishuangbanna. Different ethnic groups occupy different environments. Dai, Han, and Hui people resided in the basins and valleys and cultivated paddy rice in addition to earning income from handicrafts. Hani, Lahu, Jino, and Blang people inhabited the upland areas and cultivated upland rice and tea, and collected or grew other cash crops. The social environment has been changed since a large number of immigrants moved in to develop tropical agriculture in the 1960s. The human population increased from 199,300 in 1949 to 905,000 in 2010.
