Alpine belt

Meadows of the alpine zone. Alps , Switzerland .

The Alpine belt is a geographical and mountain belt located above the subalpine belt and below the nival belt (the belt of eternal snows). Also a biome of this belt.

The alpine zone is characterized by significant illumination and the intensity of solar radiation. The average annual air temperatures are negative. Strong winds. Over 1000 mm of atmospheric precipitation per year with a long, and often non-melting snow cover. The lower boundary of the alpine zone naturally rises from the coastal to the continental parts of the continents.

The alpine zone is characterized by an almost complete absence of trees and shrubs . Grassy communities are composed of stunted perennials , including evergreens . Often there are plants in the form of pillows and rosettes .

Many plant species growing in the alpine zone are xeromorphic . This is due to the strong heating of the plant surface in the daytime (up to +50 ° C).

Night temperatures in the alpine zone, even in summer, can drop below zero, which causes the corollas to freeze, but does not lead to their death: during the day, the flowers thaw and continue to bloom.

There are two types of alpine meadows :

• meadows dominated by monocotyledonous plants from the Cereals ( Poaceae ) and Sedge ( Cyperaceae ) families.
• meadows in which forbs predominate, composed mainly of dicotyledonous plants .

Pod - shaped plants are characteristic of the Alpine belt of the Andes .

Animals living in the alpine zone can be divided into two groups:

• species that inhabit this biome all of them - they fall into hibernation ( pikas , voles , marmots );
• species that, under adverse conditions, migrate to lower belts ( mountain sheep , chamois , tours ).

Territories belonging to the alpine zone are used as summer pastures .