Bhutan is located on the South slope of the Great Himalaya.
The Northern border between Bhutan and Tibet is above
7,000 m., but the Southern one, between Bhutan and India, is
only about 200 m.
Bhutan can be divided into three areas by altitude. Residences
start from 4,100 m. In this alpine zone annual rainfall
is 400 mm, 60-90 percent of it falling in the Monsoon season.
In this area, the main subsistence is seasonal Yak nomadism.
The 3,000-1,500 m. zone, the so-called middle inner Himalaya,
has a cold temperate climate with annual precipitation
averaging about 1,000 mm. The western region receives a
comparatively higher rainfall. Buckwheat is cultivated at the
higher elevations and rice in lower sites. Cattle breeding is also
common. Agricultural field move by season, with those at
higher elevations being cultivated in summer and the lower sites
in winter. Cattle are also relocated to lower sites in the winter.
This might have been influenced by the tradition of Yak
nomadism.
Near the southern border, at an elevation of less than
1,500 m., the climate is hotter and humid, with average annual
temperatures ranging from 15-30°C and a rainfall of 2,500-
5,000 mm in some areas. In that zone the rice is the main crop.
In cultural terms, Yak nomadism came from the North
(Tibet) and rice cultivation might have been broguht from the
South (Assam). Thus Bhutan lies at the junction of the Tibetan
and Assamese cultural zones.