Cultural and natural areas

There is a correlation between the distribution of ethno-linguistic and agro-ecological structures, with wet-season rice dominant in the Mekong Valley populated by the Tai-Kadai, and swidden rice (ray) dominant in the highlands of the North and South populated by Austro-Asiatics. Relief explains certain overlaps, such as wet-season rice in the Austro-Asiatic area of settlement on Savannakhet Plain.

This map suggests a way to organize the territorial entities in the northern part of the country. The entire province of Xayabury, with a combination of wet-season rice and swidden rice and a Tai-Kadai population, is clearly distinct from the central block of the North and bears more resemblance to Vientiane province. This same combination, with the addition of Hmong people, characterizes the two provinces of the North-East, which are completely differentiated from the central block of the North and are also attached to Vientiane province. The same agro-ecological combination linked with Tibeto-Burmans  and  Ho  also  distinguishes  the peripheries to the north and north-west of this central block.