<Notes>Vertical Zoning of Monsoon Asia by Agricultural Landuse : A Progress Report

Abstract

Based on field work in India and Nepal, monsoon Asia is classified into five vertical zones in terms of agricultural landuse. The five zones are, from low to high altitude, 1) paddy dominant zone, 2) maize-millet and paddy zone with tropical plants, 3) maize-millet and paddy zone without tropical plants, 4) maize and wheat zone, and 5) potato and bitter buckwheat zone. This last has many animals. These zones correspond well to the topographic regions. the paddy dominant zone coincides with the Lowland and Highland regions. The maize zones, that is the zones 2) to 4) fall in the Hill region. The potato and bitter buckwheat zone corresponds to the Alpine region. Roughly speaking, the Lowland and Highland regions are the domain of rice, the Hill region of upland crops, and the Alpine region of animals. More detailed analysis reveals that the domain of rice is further divided into two areas, i.e. the photo-sensitive rice dominant area and the non photo-sensitive rice dominant area. The former is an area of poor drainage, while the latter is an area of good drainage. The domain of upland crops is also subdivided. There are a lower horizon of monsoon crops, a middle horizon of Mediterranean type crops and a higher horizon of Alpine crops. At the highest altitude, the landuse pattern becomes a nomadic one, heavily dependent on animal raising rather than soil cultivation.