What determines the set of high-altitude belts? High-altitude belts of the Caucasus

The structure of the high altitude zone of the Caucasus is the most complete in comparison with other mountains of the Russian Federation. According to UNESCO World Heritage Sites, the region is remarkable for a variety of geology, ecosystems and species, contains vast tracts of unbroken mountain forests unique on a European scale. Consider the example of this majestic mountain system, on which depends the set of high-altitude belts. We will find out how the population uses the natural conditions and resources of each of the vertical zones.

High-altitude belts in the mountains

Vertical zonality - or altitudinal zonality - a geographical pattern that manifests itself in the change of plant communities from foothills to peaks. It differs from the latitudinal alternation of natural zones on the plains, which is caused by a decrease in the amount of solar radiation from the equator to the poles. A complete set of high-altitude belts is represented in the high mountains, which are in the equatorial and tropical belt. Let's list all possible vertical natural zones (from the foot to the top):

1. Wet equatorial forests (up to a height of 1200 m).
2. Mountain forests.
3. High-altitude forests (up to 3000 m).
4. Low-grown, twisted trees, shrubs (up to 3800 m).
5. High-mountain meadows (up to 4500 m).
6. Stony wasteland, bare rocks.
7. Snow, mountain glaciers.

What determines the set of high-altitude belts?

The existence of high-altitude belts is explained by a decrease in temperature, pressure and humidity with increasing altitude. The air is cooled by an average of 6 ° C when climbing 1 km. At every 12 meters of altitude, there is a decrease in atmospheric pressure by 1 mm Hg.

In the mountains, which are at different distances from the equator, the vertical zoning is significantly different. At the same geographical latitude, there are sometimes different natural complexes.

Let's enumerate what the set of high-altitude belts depends on, what conditions influence their formation:

• Geographical location of the mountains. The closer to the equator, the more vertical zones.
• The lowlands are usually occupied by the natural community that dominates the adjacent plain.
• Height of mountains. The higher they are, the richer the set of belts. The farther from warm latitudes and the lower the mountains, the smaller the zones (in the Northern Urals there are only 1-2 of them).
• The proximity of the seas and oceans over which warm and humid air forms.
• The effect of dry cold or warm air masses coming from the continent.

Vertical change of natural zones in the mountains of the Western Caucasus

There are high-altitude belts of the Caucasus, which are related to two types of vertical zoning: continental and coastal (coastal). The second is represented in the mountains of the Western Caucasus, experiencing the influence of the Atlantic, moist sea air.

We list the main high-altitude belts from the foothills to the peaks:

1. Meadow steppes, interrupted by curtains of oak, hornbeam, ash (up to 100 m).

2. Forest belt.

• Broad-leaved mountain forests (up to a height of 600 m). Occasionally in this zone there are coniferous trees (spruce, Caucasian fir). Some sites resemble moist subtropics with an evergreen undergrowth, in which grow vines, boxwood, yew, laurel cherry.
• Belt of mixed forests (above 1200 m).
• Dark coniferous forest vegetation.

3. Subalpine krivolese and high grass meadows (at an altitude of 2000 m).

4. Low-grass alpine meadows, rich in bells, grass and umbellate plants.

5. Nival zone (at an altitude of 2800-3200 m).

The Latin word nivalis in translation means "cold". In this belt, except for bare rocks, snow and glaciers, there are alpine plants: buttercups, primroses, plantain and others.

Altitudinal zonality of the Eastern Caucasus

In the east, slightly different altitudinal belts of the Caucasus are observed, which are often called the Continental or Dagestan type of vertical zoning. Semideserts are distributed in the foothills, which are followed by dry steppes with predominance of grasses and wormwood. Above are thickets of xerophytic shrubs, rare forest vegetation. The next high-mountainous natural zone is represented by a mountain steppe, grasslands. On the slopes that receive part of the Atlantic moist air, there are forests from broad-leaved species (oak, hornbeam and beech). In the Eastern Caucasus, the forest belt is replaced by subalpine and alpine meadows with a predominance of xerophytic plants at an altitude of about 2,800 m (in the Alps the border of this belt is at an altitude of 2,200 m). The nival zone extends at an altitude of 3600-4000 m.

Comparison of the altitudinal zonality of the Eastern and Western Caucasus

The number of high-altitude belts of the Eastern Caucasus is less than that of the Western Caucasus, which is due to the influence on the formation of natural zones in the mountains of air masses, relief and other factors. For example, warm and moist Atlantic air almost does not penetrate to the east, it is detained by the main ridge. At the same time, cold temperate air does not penetrate into the western part of the Caucasus.

The main differences in the structure of the high-altitude belts of the Eastern Caucasus from the Western:

• Presence in the foothills of semi-deserts;
• The lower belt of the dry steppes;
• A narrow forest zone;
• Thickets of xerophytic bushes at the lower boundary of the forest belt;
• Absence of a belt of coniferous forests
• Steppes in the middle and high parts of the mountains;
• Expansion of the mountain meadow belt;
• Higher location of snow and glaciers.
• Forest vegetation only in valleys;
• Almost no dark coniferous trees.

Economic activity of the population

The composition of the natural zones of the Caucasus is caused by the change in climatic parameters within the mountain system from the foot to the tops, and also from the west to the east. Having ascertained, on which the set of high-altitude belts depends, it should be noted that the region has a high population density, especially on the Black Sea coast. The fertile steppe plains of the Ciscaucasia are almost completely plowed up and are occupied for sowing cereals, technical and melon crops, orchards, vineyards. Developed subtropical agriculture, including cultivation of tea, citrus, peaches and walnuts. Mountain rivers have a large reserve of hydropower, they are used for irrigation of low-water areas. Steppes, semi-deserts and meadows serve as pastures. In the mountain-forest belt, timber is harvested.

All high-altitude belts in the Caucasus mountains have great opportunities for tourism. The system of medium and high mountain ranges, covered with forest, glaciers and snow, attracts fans of alpine skiing and snowboarding. The routes suggest overcoming rocks, snow-covered slopes, mountain rivers. Clean air of mixed forests, picturesque landscapes, seashore - the main recreational resources of the Caucasus.