In mountainous areas, the temperature, pressure, and oxygen content of the air decrease with increasing altitude, while precipitation, daily heat fluctuations, and solar irradiance increase.

Altitudinal zones

In mountain regions, temperatures are lower all year round, and the annual rainfall is high. With increasing altitudes, corresponding climate zones form. Climatically adapted vegetation demonstrates the levelling process.

Where are the boundaries?

One of the most important boundaries separating the zones is the forest boundary; there is no contiguous forest above it. The upper limit of solitary trees is marked by the tree line. Above the snow line is the realm of eternal snow. Between the tree line and the snow line lies the frost line.

The mountains of the temperate zone

The altitudinal belts of the temperate zone are well illustrated by the Alps. Between 500-800 metres, the typical vegetation is deciduous forest. Up to 1500m, beech and pine forests are characteristic, followed by pine forests with dwarf shrubs and rhododendrons. Above the forest boundary (timberline/tree line), dwarf shrubs, mosses and lichens occur up to 2800m, where the realm of eternal frost begins.

The tropical zone

The altitudinal belts of the mountain ranges of the tropical zone are illustrated by the Andes with one of the most complete set of zones.