The subtropical climatic zone is the most bearable for people. It occupies a territory between 30 and 40 parallels, but as in other rules, there are exceptions here. Typically, the subtropical climatic zone is characterized by long, sunny, dry and hot summers, short, mild and humid winters, and very short transitional seasons (spring and autumn). During the summer months, this climatic zone is strongly influenced by tropical air masses. In winter, in most cases, the formation of snow cover is possible.
The most strong influence this part of the year have air masses coming from. An interesting fact is that despite the limited territorial distribution The subtropical climate zone is home to a huge part of the human population. It occupies the northern part, the southern part, the southern parts, the central parts and, the most southern parts, the southern coast, the northern island, the southern, southeastern, parts of the southwestern, but the most classic and pronounced features of the subtropical climate in the lands surrounding the Mediterranean Sea. For this reason, the subtropical climate is often referred to as Mediterranean. But like other climatic zones, the subtropical climate can be very different in 
depending on the general geographic characteristics of the place where it is located. The Mediterranean Sea, for example, is characterized by a milder climate than other subtropical regions of the planet. One of 
the main reasons for this phenomenon are high mountain ranges that separate the colder northern from the warmer southern part of the continent. These mountains play the role of a serious climatic barrier. The Perineas, Massif Central (), the Alps and high mountains in the Balkans stop cool air masses coming from the North and this makes the local subtropical climate noticeably warmer than in other parts of the world. Second important factor simulating the local subtropical climate - great openness Mediterranean Sea the largest and hottest desert on our planet -. In northwestern Africa, apart from the Atlas Mountains, there are no other barriers stopping hot and dry air masses going south. The third important factor that forms a mild climate in this part of the world is warm currents circulating in the Mediterranean. As a result, the climate near the Mediterranean 
softens further. For example, the capital of the United States, Washington, and the Spanish island, are located at almost the same latitude in the subtropical climate zone. But the commonality of these two places is only in 
this. Winter temperatures in Washington are low - between 0 and 5 ° C. Heavy snowfalls occur. Winter in Ibiza is completely different. On this heavenly Mediterranean island, the temperature in January is + 16 ° C, but on sunny days it can go up to + 25 ° C. It is clear that the conditions of Washington and Ibiza, despite the same geographical width, are very different. But the differences can be even deeper. Busan, located in the southern part of South Korea, is located in a subtropical climate zone, but here you can see all four different seasons. Summers are very hot and winters can be extremely harsh. Average January temperatures are between 0 and 5 ° C, but can sometimes drop below (-10) ° C. Snow storms are not uncommon here. At the same time, the island, which is located in the eastern part of the Mediterranean Sea, has a very hot and sunny climate almost all year round. The beach season lasts from March to the end of November, but sometimes warm and sunny weather persists until mid-December. January and February are almost entirely warm and sunny with daytime 
temperatures up to + 17-18 ° C. Despite the fact that the subtropical climate is wide 
widespread on our planet, areas with a classic subtropical climate are quite limited. They occupy the central parts of Chile, the southern, southwestern part of South Africa, and the southern shores of Australia. 50% of the regions of the entire planet with a classic subtropical climate are located near the Mediterranean Sea. For this reason, this climate is known as Mediterranean. Due to its mild, pleasant climate, the shores of the Mediterranean Sea are the most coveted place in the world to live, just like Southern California. The vegetation here is represented mainly by evergreen, hard-leaved species such as orange, lemon, olive, mandarin and some conifers, such as cypress. Animal species are diverse - puma, lynx, goat, deer, birds, reptiles, etc.
Subtropical climatic zones - geographic zones of the Northern and Southern hemispheres of the globe, stretching between the tropical and moderate belts... The terrain located in this belt is characterized by the alternation of temperate and tropical climatic regimes. This is due to the seasonal rhythms of general circulation. atmospheric air: in the summer, the subtropical zones are under the influence of the trade wind climate regime, in winter - under the influence of cyclonic circulation of moderate air masses. The exception is the eastern outskirts, where summer monsoon precipitation is observed.
V summer period the average air temperature is more than 20 ° С, in winter - more than 4 ° С. With the penetration of polar air masses, there is a high probability of frost and slight frost (up to -10 ° C). Above land in the subtropical zone level atmospheric precipitation and their regime varies considerably from coastal regions of the ocean to inland ones. This, together with an increase in the continentality of the climate in the same direction, is responsible for significant landscape differences in the characteristics of natural zones.
On the territory of each of the continents in the subtropical zones, three main regions are clearly distinguished: the western oceanic, or Mediterranean, with high humidity in winter; continental with insufficient air humidity all year round; eastern oceanic, or monsoon, with high air humidity in summer.
Natural zones of the subtropical belt
In the western oceanic region, the so-called semi-dry subtropics, there is a zone of stiff-leaved shrubs and forests on brown soils. In the Northern Hemisphere, after the zone of hard-leaved forests and shrubs, there are zones of subtropical steppes on gray-brown soils to the southeast. To the east, there are zones of subtropical semi-deserts and deserts of the continental region on gray-brown soils and gray soils. These are dry subtropics.
In the Southern Hemisphere in the continental regions of the subtropics lies a zone of subtropical steppes on gray-brown soils. In the eastern regions there are humid subtropics with evergreen deciduous forests, and in higher latitudes, deciduous broadly deciduous forests with an admixture of evergreens tree species plants on red soils, yellow soils and yellow-brown soils. In mountainous areas, the subtropical zone corresponds to forest-meadow (in humid areas) and forest-steppe (in dry areas) levels of altitudinal zonality.
On the territory of the CIS countries, there is a section along the upper border of the subtropical belt, therefore the nature here does not correspond to that typical for the subtropics. The subtropics occupy the Black Sea coast of the Caucasus, the southern coast of Crimea, the Colchis, Kura-Araks and Lankaran lowlands, the Alazan valley and the southern outskirts of the deserts of Central Asia.
At the expense of economic activity humans in the subtropics, forests are often replaced by plantation and field landscapes. In the fauna, there is a joint habitation of species of the temperate and tropical zones. Oceanic waters in the subtropics are characterized by relatively high temperatures (15-16 ° C) and increased salinity. As a result of weak vertical mixing of oceanic waters, the concentration of oxygen and plankton in them decreases. This is due to the small number of commercial fish.
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Zoning - the change natural components and the natural complex as a whole from the equator to the poles. Zoning is based on the different influx of heat, light, atmospheric precipitation to the Earth, which, in turn, are already reflected in all other components, and above all - soils, vegetation and fauna.
Zoning is typical for both land and the World Ocean.
The largest zonal subdivisions of the geographic envelope are geographic zones. The belts differ from each other primarily in temperature conditions.
The following geographical zones are distinguished: equatorial, subequatorial, tropical, subtropical, temperate, subpolar, polar (Antarctic and Arctic).
Inside the belts on land, natural zones are distinguished, each of which is characterized not only by the same type of temperature conditions and moisture, which leads to a commonality of vegetation, soils and fauna.
You are already familiar with the zone of arctic deserts, tundra, forest zone of the temperate climatic zone, steppes, deserts, humid and dry subtropics, savannahs, humid evergreen equatorial forests.
Transitional areas are distinguished within natural zones. They are formed as a result of a gradual change in climatic conditions. To such transition zones include, for example, forest-tundra, forest-steppe and semi-desert.
Zoning can be not only latitudinal, but also vertical. Vertical zoning is a natural change in height and depth of natural complexes. For mountains, the main reason for this zoning is the change in temperature and moisture content with height, and for the depths of the ocean - heat and sunlight.
The change of natural zones depending on the height above sea level in mountainous areas is called, as you already know, high-altitude zonation.
It differs from horizontal zoning in the length of the belts and the presence of a belt of alpine and subalpine meadows. The number of belts usually increases in high mountains and closer to the equator.
Natural areas
Natural areas- large subdivisions of the geographic envelope with a certain combination of temperature conditions and moisture regime. They are classified mainly by the prevailing type of vegetation and regularly change in the plains from north to south, and in the mountains - from the foothills to the peaks. Natural zones of Russia are shown in Fig. one.
The latitudinal distribution of natural zones on the plains is explained by the intake of an unequal amount of solar heat and moisture on the earth's surface at different latitudes.
The resources of flora and fauna of natural zones are biological resources territory.
The set of altitudinal belts depends primarily on the latitude at which the mountains are located and what their height is. It should also be noted that, for the most part, the boundaries between the altitudinal zones are not clear-cut.
Let us consider in more detail the features of the placement of natural zones using the example of the territory of our country.
Polar desert
The very north of our country is the Northern Islands Arctic Ocean- located in a natural area polar (arctic) deserts. This zone is also called ice zone. The southern border roughly coincides with the 75th parallel. The natural zone is characterized by the dominance of the Arctic air masses. The total solar radiation is 57-67 kcal / cm 2 per year. Snow cover lasts 280-300 days a year.
In winter, the polar night dominates here, which at a latitude of 75 ° N. sh. lasts 98 days.
In summer, even round-the-clock lighting is not able to provide this area with enough warmth. The air temperature rarely rises above 0 ° С, and the average July temperature is + 5 ° С. Drizzling precipitation can last for several days, but there are practically no thunderstorms and showers. But fogs are frequent.
Rice. 1. Natural zones of Russia
A significant part of the territory is characterized by modern glaciation... There is no continuous vegetation cover. Near-glacial areas of land on which vegetation develops are small. On the placers of pebbles, fragments of basalt and boulders, mosses and crusty lichens "settle". Occasionally there are poppies and saxifrage, which begin to bloom when the snow has barely had time to melt.
The fauna of the Arctic desert is represented mainly by Marine life... This is a harp seal, a walrus, ringed seal, sea hare, beluga whale, Harbour porpoise, killer whale.
Varied in northern seas species of baleen whales. Blue and bowhead whales, sei whales, fin whales, humpback whales are rare and endangered species and are listed in the Red Book. The inner side of the long horny plates that replace the whale's teeth are split into hairs. This allows the animals to filter a large volume of water, harvesting plankton, which is the basis of their diet.
The polar bear is also a typical representative of the animal world of the polar desert. "Maternity hospitals" for polar bears are located in Franz Josef Land, Novaya Zemlya, about. Wrangel.
In summer, numerous bird colonies nest on the rocky islands: gulls, guillemots, guillemots, auk, etc.
There is practically no permanent population in the polar desert zone. The weather stations operating here monitor the weather and the movement of ice in the ocean. On the islands they hunt Arctic foxes in winter and game birds in summer. Fishing is carried out in the waters of the Arctic Ocean.
Steppe
Steppes extend to the south of the forest-steppe zone. They are distinguished by the absence of forest vegetation. The steppes stretch in a narrow continuous strip in the south of Russia from the western borders to Altai. Further to the east, the steppe areas have focal distribution.
The climate of the steppes is moderately continental, but drier than in the zone of forests and forest-steppe. Annual total solar radiation reaches 120 kcal / cm 2. The average January temperature at the start is -2 ° С, and in the east -20 ° С and below. Summer in the steppe is sunny and hot. The average July temperature is 22-23 ° C. The sum of active temperatures is 3500 ° C. Annual precipitation is 250-400 mm. Showers are frequent in summer. The moisture coefficient is less than one (from 0.6 in the north of the zone to 0.3 in the southern steppes). A stable snow cover lasts up to 150 days a year. Thaws often occur in the west of the zone, so the snow cover there is thin and very unstable. The dominant steppe soils are chernozems.
Natural plant communities are represented mainly by perennial, drought and frost-resistant grasses with a powerful root system. These are, first of all, cereals: feather grass, fescue, wheat grass, serpentine, thin-legged, bluegrass. In addition to cereals, there are numerous representatives of forbs: astragalus, sage, carnation - and bulbous perennials, such as tulips.
The composition and structure of plant communities change significantly in both latitudinal and meridional directions.
In the European steppes, narrow-leaved grasses form the basis: feather grass, fescue, bluegrass, fescue, thin-legged, etc. There are many brightly blooming forbs. In summer, feather grass sways like waves in the sea, here and there you can see lilac irises. In the more arid southern regions, in addition to cereals, wormwood, breast milk, and cinquefoil are common. There are many tulips in the spring. In the Asian part of the country, tansy and cereals predominate.
Steppe landscapes are fundamentally different from forest landscapes, which determines the originality of the fauna of this natural zone. Typical animals of this zone are rodents (the largest group) and ungulates.
Ungulates are adapted to long-term movements across the endless expanses of the steppes. Due to the thinness of the snow cover, plant food is available in winter as well. Bulbs, tubers, rhizomes play an important role in nutrition. For many animals, plants are also the main source of moisture. Typical representatives of ungulates in the steppes are turs, antelopes, tarpans. However, most of these species were exterminated or pushed southward as a result of human economic activity. Saigas, which were widespread in the past, have survived in some areas.
Of the rodents, the most common are the gopher, vole, jerboa, etc.
Ferret, badger, weasel, fox also live in the steppe.
Of the birds, the bustard, little bustard, partridge, steppe eagle, buzzard, and kestrel are typical of the steppes. However, even these birds are now rare.
There are much more reptiles than in the forest zone. Among them, we single out the steppe viper, snake, common snake, nimble lizard, shitomordnik.
The wealth of the steppes - fertile soil... The thickness of the humus layer of chernozems is more than 1 m. It is not surprising that this natural zone is almost completely developed by man and natural steppe landscapes are preserved only in reserves. In addition to the high natural fertility of chernozems, Agriculture promote and climatic conditions favorable for horticulture, the cultivation of heat-loving cereals (wheat, corn) and industrial (sugar beet, sunflower) crops. In connection with the insufficient amount of atmospheric precipitation and frequent droughts, irrigation systems have been built in the steppe zone.
The steppe is a zone of developed animal husbandry. Here they breed a large cattle, horses, bird. Conditions for the development of animal husbandry are favorable due to the presence of natural pastures, feed grains, waste from the processing of sunflowers and sugar beets, etc.
Developed in the steppe zone various industries industries: metallurgy, mechanical engineering, food, chemical, textile.
Semi-deserts and deserts
In the southeast of the Russian Plain and in the Caspian Lowland, there are semi-deserts and deserts.
The total solar radiation here reaches 160 kcal / cm 2. The climate is characterized by high air temperatures in summer (+22 - + 24 ° C) and low in winter (-25-30 ° C). Because of this, there is a large annual temperature range. The sum of active temperatures is 3600 ° C and more. In the zone of semi-deserts and deserts, a small amount of atmospheric precipitation falls: per year, on average, up to 200 mm. In this case, the moisture coefficient is 0.1-0.2.
The rivers located in the semi-desert and desert zones are fed almost exclusively by the spring melting of snow. Most of them flow into lakes or are lost in the sands.
Typical soils of the semi-desert and desert zone are chestnut. The amount of humus in them decreases in the directions from north to south and from west to east (this is primarily due to a gradual increase in the sparseness of vegetation in these directions), therefore, in the north and west, the soils are dark chestnut, and in the south - light chestnut ( the humus content in them is 2-3%). In the depressions of the relief, the soils are saline. There are salt marshes and solonetzes - soils, from the upper layers of which, due to leaching, a significant part of the readily soluble salts is carried away to the lower horizons.
Plants in semi-deserts are usually low, drought-resistant. The semi-deserts of the south of the country are characterized by such plant species as treelike and gnarled hodgepodge, camel thorn, and juzgun. Feather grasses and fescue are dominant on the uplands.
Steppe grasses alternate with spots of wormwood and romantic yarrow.
The deserts of the southern part of the Caspian lowland are the kingdom of semi-shrub polynyas.
For life in conditions of lack of moisture and salinization of the soil, plants have developed a number of adaptations. Solyanka, for example, has hairs and scales that protect them from excessive evaporation and overheating. Others, such as tamariks, kermek, "acquired" special salt-removing glands to remove salts. In many species, the evaporating surface of the leaves has decreased, and their pubescence has occurred.
The growing season for many desert plants is short. They manage to complete the entire development cycle for a favorable time of the year - spring.
The fauna of semi-deserts and deserts is poor in comparison with the forest zone. The most common reptiles are lizards, snakes, and turtles. There are many rodents - gerbils, jerboas and poisonous arachnids - scorpions, tarantulas, karakurt. Birds - bustard, little bustard, lark - can be seen not only in the steppes, but also in semi-deserts. Of the most large mammals note the camel, the saiga; there are korsak, wolf.
The delta of the Volga and the Akhtubinskaya floodplain are a special area in the zone of semi-deserts and deserts of Russia. It can be called a green oasis in the middle of a semi-desert. This territory is distinguished by its thickets of reed-reeds (it reaches 4-5 m in height), shrubs and shrubs (including blackberries), intertwined with climbing plants (hops, bindweed). In the creeks of the Volga delta, there are many algae, white water lilies (including the Caspian rose and water walnut preserved from the preglacial period). There are many birds among these plants, among which herons, pelicans and even flamingos stand out.
The traditional occupation of the population in the semi-desert and desert zone is cattle breeding: sheep, camels, and cattle are raised. As a result of overgrazing, the area of unsecured scattered sand increases. One of the measures to combat the advance of the desert - phytomelioration - a set of measures for the cultivation and maintenance of natural vegetation. For fixing the dunes, such plant species as giant spikelet, Siberian wheatgrass, saxaul can be used.
Tundra
The vast expanses of the Arctic Ocean coastline from the Kola Peninsula to the Chukchi Peninsula are occupied tundra. The southern border of its distribution is practically owls
e falls by the July isotherm of 10 ° C. Furthest north southern border tundra moved to Siberia - north of 72 ° N latitude. In the Far East, the influence of cold seas has led to the fact that the border of the tundra reaches almost the latitude of St. Petersburg.
The tundra receives more heat than the polar desert zone. The total solar radiation is 70-80 kcal / cm 2 per year. However, the climate here continues to be characterized by low air temperatures, short summers, and severe winters. The average air temperature in January reaches -36 ° С (in Siberia). Winter lasts 8-9 months. At this time of the year, southerly winds blowing from the mainland prevail here. Summer is distinguished by an abundance of sunshine, unstable weather: strong northerly winds often blow, bringing cooling and precipitation (especially in the second half of summer there are often heavy drizzling rains). The sum of active temperatures is only 400-500 ° C. The average annual rainfall reaches 400 mm. Snow cover lasts 200-270 days a year.
The prevailing types of soils in this zone are peat-bog and slightly podzolic. Due to the spread of permafrost, which has a water-resistant property, there are many swamps here.
Since the tundra zone has a significant length from north to south, within its limits climatic conditions change markedly: from severe in the north to more moderate in the south. In accordance with this, the arctic, northern, they are also typical, and southern tundras are distinguished.
Arctic tundra occupy mainly the arctic islands. The vegetation is dominated by mosses, lichens, flowering plants are found, in comparison with the arctic deserts there are more of them. Flowering plants represented by shrubs and perennial grasses. Common willow and creeping willow, dryad (partridge grass). Of the perennial grasses, the most common are the polar poppy, small sedges, some cereals, and saxifrage.
Northern tundra distributed mainly on the mainland coast. Their important difference from the arctic ones is the presence of a closed vegetation cover. Mosses and lichens cover 90% of the soil surface. Green mosses and bushy lichens predominate; lichen is often found. The species composition of flowering plants is also becoming more diverse. There are saxifrage, ozhiki, viviparous mountaineer. From shrubs - lingonberry, blueberry, wild rosemary, crowberry, as well as dwarf birch (dwarf birch), willow.
V southern tundra, as in the northern ones, the vegetation cover is continuous, but it can already be divided into tiers. The upper tier is formed by dwarf birch and willows. Medium - grasses and shrubs: crowberry, lingonberry, blueberry, wild rosemary, sedge, cloudberry, cotton grass, cereals. Lower - mosses and lichens.
The harsh climatic conditions of the tundra "forced" many plant species to "acquire" special adaptations. So, plants with creeping and creeping shoots and leaves collected in a rosette better "use" the warmer ground air layer. Short stature helps to survive the harsh winter. Although due to strong winds the thickness of the snow cover in the tundra is small, it is enough to take cover and survive.
Some adaptations "serve" plants in the summer. For example, cranberries, dwarf birch, and crowberry “struggle” to retain moisture by “reducing” the size of the leaves as much as possible, thereby reducing the evaporating surface. In dryad and polar willow, the underside of the leaf is covered with dense pubescence, which impedes the movement of air and thereby reduces evaporation.
Almost all plants in the tundra are perennial. For some species, the so-called viviparity is characteristic, when, instead of fruits and seeds, the plant has bulbs and nodules, which quickly take root, which provides a "gain" in time.
The animals and birds that constantly inhabit the tundra have also adapted well to the harsh natural conditions... They are saved by thick fur or fluffy plumage. In winter, animals are white or light gray in color, and in summer they are grayish brown. This helps to camouflage.
Typical animals of the tundra are arctic fox, lemming, white hare, reindeer, white polar and tundra partridges, snowy owl. In summer, the abundance of food (fish, berries, insects) attracts birds such as waders, ducks, geese, etc. to this natural area.
The tundra has a fairly low population density. The indigenous peoples here are the Sami, Nenets, Yakuts, Chukchi, etc. They are mainly engaged in reindeer herding. The mining of minerals is actively carried out: apatite, nepheline, non-ferrous metal ore, gold, etc.
The railway connection in the tundra is poorly developed; an obstacle to the construction of roads is permafrost.
Forest tundra
Forest tundra- transition zone from tundra to taiga. It is characterized by the alternation of areas occupied by forest and tundra vegetation.
The climate of the forest-tundra is close to that of the tundra. The main difference: the summer here is warmer - the average July temperature is + 11 (+14) ° С - and longer, but the winter is colder: the influence of the winds blowing from the mainland affects.
The trees in this zone are undersized and bent to the ground, have a curved appearance. This is due to the fact that permafrost and waterlogged soil do not allow plants to have deep roots, and strong winds bend them to the ground.
In the forest-tundra of the European part of Russia, spruce prevails, pine is less common. Larch is widespread in the Asian part. Trees grow slowly, their height usually does not exceed 7-8 m. Due to strong winds, the flag-like shape of the crowns is widespread.
The few animals that spend the winter in the forest-tundra are perfectly adapted to the local conditions. Lemmings, voles, tundra partridge make long passages in the snow, feed on leaves and stems of evergreen tundra plants. With an abundance of food, lemmings even bring offspring at this time of the year.
On small forests and bushes along the rivers, animals from the forest zone enter the southern regions: white hare, brown bear, ptarmigan. There are wolf, fox, ermine, weasel. Small insectivorous birds fly in.
Subtropics
This zone, which occupies the Black Sea coast of the Caucasus, is characterized by the smallest extent and area in Russia.
The total solar radiation reaches 130 kcal / cm 2 per year. Summer is long, winter is warm (average January temperature is 0 ° С). The sum of active temperatures is 3500-4000 ° C. Under these conditions, many plants can develop all year round. In the foothills and on mountain slopes, 1000 mm or more of atmospheric precipitation falls per year. On flat areas, snow cover is practically not formed.
Fertile red earth and yellow earth soils are widespread.
The subtropical vegetation is rich and varied. Vegetable world represented by evergreen rigid-leaved trees and shrubs, among which we will name boxwood, laurel, cherry laurel. Oak, beech, hornbeam, maple forests are widespread. Thickets of trees intertwine with liana, ivy, wild grapes. There are bamboo, palms, cypress, eucalyptus.
Among the representatives of the animal world, we note the chamois, deer, wild boar, bear, pine and stone marten, Caucasian black grouse.
The abundance of warmth and moisture allows the cultivation of such subtropical crops as tea, tangerines, lemons. Large areas are occupied by vineyards and tobacco plantations.
Favorable climatic conditions, the proximity of the sea and mountains make this region a large recreational area of our country. There are numerous camp sites, rest houses, sanatoriums.
In the tropical zone there are humid forests, savannas and woodlands, deserts.
Pretty much plowed up tropical rainforest(South Florida, Central America, Madagascar, Eastern Australia). They are usually used for plantations (see atlas map).
The subequatorial belt is represented by forests and savannas.
Subequatorial moist forests located mainly in the Ganges Valley, southern part of Central Africa, on the northern coast of the Gulf of Guinea, northern South America, Northern Australia and the islands of Oceania. In drier areas, they are replaced savannah(Southeast Brazil, Central and East Africa, central regions Northern Australia, Hindustan and Indochina). Typical representatives of the animal world subequatorial belt- ruminant artiodactyls, predators, rodents, termites.
At the equator, an abundance of precipitation and high temperatures led to the presence of a zone here evergreen moist forest(Amazon and Congo basin, on the islands of Southeast Asia). The natural zone of evergreen humid forests holds the world's record for the diversity of animal and plant species.
The same natural zones are found on different continents, but they have their own characteristics. Primarily it comes about plants and animals that have adapted to living in these natural areas.
The natural area of the subtropics is widely represented on the Mediterranean coast, the southern coast of Crimea, in the southeastern United States and in other regions of the Earth.
Western Hindustan, Eastern Australia, the Parana Basin in South America, and South Africa are zones of more arid tropical savannas and woodlands. The largest natural zone in the tropical zone - desert(Sahara, the Arabian Desert, the deserts of Central Australia, California, as well as the Kalahari, Namib, Atacama). Huge spaces of pebble, sandy, rocky and saline surfaces are devoid of vegetation. The fauna is small n.
Russians, as residents of a country stretching for the most part to live in temperate latitudes with a long cold winter, I like to relax in hot countries, especially where summer is all year round. When choosing a vacation destination, managers from a travel agency must tell about the climate and weather characteristics of a particular resort, but for a final decision, knowledge is needed about the differences in climatic zones that determine favorable seasons for recreation.
Most of the popular resort areas are located in tropical and subtropical climates. Although both climatic zones belong to hot climate zones, they differ in some geographical features.
How are climatic zones formed?
Over continents and oceans are formed large air masses, homogeneous in properties. Properties are expressed in terms of the ratio of heat and moisture. If the air mass has formed over a cold continent, then by its properties it will be dry and cold. The ocean saturates the atmosphere with moisture. In hot latitudes, the air heats up and loses moisture.
On the globe, there is an alternation of warm and cold belts, so the air masses also alternate in the direction from the poles to the equator. Air masses, similar in properties, seem to encircle the planet and determine the type of climatic zone.
The tropical climate is typical for the tropical latitudes, and the subtropical for the subtropics. According to the geographical classification, the climatic zone in the tropics belongs to the main zones, and the subtropical zone belongs to the transitional ones.
Basic characteristics of a tropical climate
The tropical climate zone is located between the equator and the lines of the tropics in the northern and southern hemisphere... The tropic line is a parallel 23,5 0 , the last from the equator, where the solstice is observed 2 times a year.
The tropics are geographic latitudes with high atmospheric pressure. Therefore, the air from here spreads in those directions where the pressure is low. The tropics are characterized by constant air movement, which caused the formation of winds called trade winds.
The tropics are territory the highest year-round temperatures, where the thermometer does not drop below +18 0 С during the year, and in the deserts the temperature can reach +50 0 С. The amount of precipitation per year is up to 200 mm.
The climatic zone of the tropics is divided into two subzones:
- With a tropical dry climate (continental areas of the continents);
- With a tropical humid climate (equatorial areas on all continents).
Dry subtropics are typical for the mainland of the climatic zone, and humid ones for oceanic islands. The tropical mainland is home to some of the world's most famous vast deserts.
The main characteristics of the subtropical climate
The subtropics extend between the tropics and temperate latitudes within the boundaries of the parallels 23.5 0 and 45 0 northern and southern hemisphere... As for everyone transition belts, the subtropics are characterized by a change in the dominant air masses twice a year. As a result of the global circulation of the atmosphere, air enters the subtropics from the north for six months, and from the south for the next six months. So in the northern hemisphere, cold temperate air comes to the subtropics in winter, and dry and hot air in summer. tropical zone... The seasons of the year are defined as not tropical winter and tropical summer.
Hence, there is a large seasonal difference in temperature and rainfall. But average annual temperature it still remains positive and stays at +14 0 C.
According to the degree of moisture in the subtropical zone of each continent, the following subzones are distinguished:
- Arid (Mediterranean) climate with maximum rainfall in winter and mild summers.
- Dry subtropics with low average annual rainfall.
- Semi-humid subtropics.
- Wet subtropics.
Despite the listed internal differences, there is not a single territory among the subtropics that is similar in characteristics to the tropics.
What are the characteristics of tropical and subtropical climates
So, two climatic zones - tropical and subtropical, located in the hot zones of the Earth, have significant differences.
- Geographical position... Each of the climatic zones has a latitudinal position within the boundaries of certain parallels. They do not overlap or overlap.
- Prevailing air masses forming the climatic zone. The climate of the tropical zone is formed by hot and dry air masses over the mainland and humid air masses over the ocean. In the subtropics, temperate and tropical air alternately dominate.
- Expressed seasonality... In the tropics, there is no pronounced weather seasonality, since the tropical air has the same properties all year round. In the subtropics, warm and cold periods are expressed, albeit with a small temperature difference and positive average annual temperatures.
- Constant winds... Trade winds are characteristic of the tropics - constant winds, blowing all year round in the northern hemisphere from north to east, and in the southern hemisphere from north to west. The reason for their formation is the pressure difference between the tropics and the equator. In the subtropics, air currents with constant directional movement are not formed.
- Average annual temperatures... In the tropical zone, the average annual temperatures are + 25-30 0 С, the maximum indicators are more than +50 0 С. In the subtropics, the average annual temperatures are also positive, but there is a contrast between winter and summer temperatures: from +4 0 С to +20 0 С. Absolute the values of both winter and summer temperatures are very different from the average for the year in both directions.
- Amount of precipitation... The tropical belt is the driest belt of the Earth, where on average less than 200 mm of precipitation falls annually. In the subtropics, the amount of precipitation varies according to the seasons of the year; therefore, within the belt there are zones with their maximum amount from 500 to 700 mm per year, and zones with a minimum of 100 mm per year.
- Suitability for household use... The tropical zone, due to the aridity of the climate, is not very suitable for economic activities. In semi-arid regions, only some branches of animal husbandry have been developed on a large scale. The possibilities for crop production are limited. The climate of the subtropics has all the conditions for the development of agriculture, horticulture and recreation. The well-known large resort centers of the Mediterranean, the North American coast and Southeast Asia are located in the subtropical zone and receive annually great amount tourists.
What are the tropics?
Tropics (from the Greek tropai heliou, "the turn of the sun")- climatic zones of the Earth. In a strictly geographic sense, they are located between the equator and both latitudes 23.5 °, the extreme lines above which the Sun once a year stands at its zenith. The tropical regions are characterized by a hot climate.
Two natural-geographical belts, stretching along the tropical parallels between the subequatorial and subtropical belts. The formation of the tropics is associated with constantly high atmospheric pressure and the year-round action of the trade winds. This leads to persistently low cloud cover, low (less than 200 mm per year) amount of atmospheric precipitation and the highest air temperatures on Earth.
Against the background of average winter temperatures not lower than 10 ° С and summer temperatures up to 35 ° С, several heat poles stand out: in the southern hemisphere + 53 ° С (Australia), and in the north + 57.8 ° С (Libyan desert). The average annual air temperature in Ethiopia is 32.2 ° С, the water temperature in the Persian Gulf reaches 35 ° С.
The greatest deserts of the Earth are located on land in the tropics: Sahara and Libyan (Africa), Nefud (Arabia), Tar (Pakistan), Big Sandy, Gibon (Australia), Kalahari (Africa), in the eastern foothills of the Andes in South America.
Tropical climate
Tropical climate- a type of climate typical for the tropics. According to the classification adopted for the climate by V.P. Köppen, it is defined as a non-arid climate in which the average temperature remains above 18 ° C (64.4 ° F) all 12 months of the year.
The tropical climate is characterized by small seasonal temperature fluctuations. In the Northern Hemisphere in the north, the tropics pass into the subtropics, in the south - into the subequatorial belt.
The tropical climate is divided (by precipitation) into two subbelts: tropical dry climate and tropical humid climate... The first type of climate is typical for almost everyone tropical deserts, the second - for oceanic islands located in low latitudes.
What are subtropics?
Subtropics- the climatic zone of the Earth. The subtropics are located between the tropics at the equator and temperate latitudes, that is, approximately between 30 ° and 45 ° north and south latitude. These regions tend to have tropical summers and non-tropical winters. The subtropics are often divided into arid (Mediterranean climate), humid and semi-humid. Summer is tropical, winter is moderate air masses. Significant seasonal differences in temperature and precipitation. Snowfalls are possible.
A common definition defines a climate as subtropical if the average annual temperature is more than 14 degrees Celsius, but the average temperature of the coldest month (January or July, sometimes February or August) is below this mark, but exceeds 0 degrees.
In the subtropics, relics of the Early Cenozoic (Middle Cretaceous) have been preserved.
Geographical position
The subtropics, the natural (geographic) belts of the Earth, are located in the Northern and Southern Hemispheres between the tropical and temperate zones.
Temperature regime and precipitation
The average monthly temperature in summer is above 23 ° C, in winter from 3 ° C and above, as a result of polar air intrusions, frosts down to −1 ... −5 ° C, small and occasionally large (up to −15 ... −20 ° C) frosts are possible ... Within the subtropical land, the amount of atmospheric precipitation and their regime undergo significant changes from the oceanic regions to the inland ones, which, combined with an increase in the climate continentality in the same direction, determines significant landscape differences in the formation of natural zones.
Subtropical subtypes
On each of the continents in the subtropics, three main sectors are clearly distinguished: the western oceanic, or Mediterranean climate, with winter moisture; continental climate with sparse moisture all year round and eastern oceanic, or monsoon climate, with abundant summer moisture. In the western oceanic sector - semi-dry subtropics - there is a zone of Mediterranean hard-leaved forests and shrubs on brown soils.
In the Northern Hemisphere, zones of hard-leaved forests and shrubs are replaced to the southeast by zones of subtropical steppes on gray-brown soils, which, in turn, move in the east to zones of subtropical semi-deserts and deserts of the continental sector on gray-brown soils and gray soils - dry subtropics.
In the Southern Hemisphere, subtropical areas in the continental sectors are characterized by subtropical steppes on gray-brown soils; for areas of subtropics in the eastern sectors - humid subtropics with a predominance of evergreens, in higher latitudes - summer-green broad-leaved forest formations with the participation of evergreen species on yellow-brown soils, yellow soils and red soils and black soil, there is a lot of precipitation.
Subtropics in the CIS countriesWet subtropics occupy the central and southern parts of the Black Sea coast of the Caucasus and the Colchis lowland; semi-humid subtropics (with manifestations of dryness in summer) - Lankaran lowland of Azerbaijan; Mediterranean semi-dry subtropics - the southern coast of Crimea, dry subtropics - the Alazani Valley of Georgia, the Kura-Araks lowland of Azerbaijan in the Transcaucasia and the southern outskirts of the deserts of Central Asia. In the mountains of the subtropical belt, forest-meadow (in humid regions) and forest-steppe (in dry) landscapes are observed.
Economic value
Subtropics- the homeland and cradle of the most ancient civilizations of mankind. The most ancient civilizations have continuously existed in the subtropics over the past millennia, therefore, the forests in the subtropics are greatly reduced; plantations and field landscapes are widely developed. The fauna is characterized by a mixture of temperate and tropical species.The ocean within the subtropics is characterized by high temperature (+15 ... +16 ° C) and salinity, however, weak vertical mixing of oceanic waters reduces the content of oxygen and plankton in them, which determines a small number of commercial fish. The Black Sea basin is a typical example of this.We are used to associating the concept of the tropics with constant heat. But a hot climate is characteristic, although very many, but not all areas of the tropics. There are also places where cool foggy weather prevails, but nevertheless there is never not only frost, but also zero degrees. In such foggy places, even a special vegetation formation of a foggy tropical forest can be found.Thus, the climatic limits of the tropics are quite wide, but a common feature of the tropical climate is that the air temperature here never drops to 0 °. But even to this limit the air temperature sometimes approaches only in some mountainous regions of the tropics. In most places, the average monthly air temperature, even in the coldest months, is above + 18 ° C, and sometimes even more.By air and soil moisture in the tropics big variety: from humid rainforest to arid deserts.Rainforests (gileas) are represented by the largest tracts in the Amazon Basin, in the Congo Basin and on the islands of the Malay Archipelago. These forests are characterized by: an extraordinary richness in species of trees, epiphytes, lianas and other life forms, the absence of kidney scales in trees, a varied height of trees, as a result of which the upper surface of all crowns appears to be wavy, relatively not abrupt change seasonal aspects, evergreen plants. On the surface of the soil of a humid tropical forest, if it is not pampered, there is little or no sun glare at all, eternal twilight reigns here.Soil wet rainforest predominantly red, of the laterite type. Their humidity is high, since these forests are located in places with large quantity annual precipitation, from 1500 to 4000 mm and even more.In the tropics, there are transitions from tropical rainforests to deserts, where the annual rainfall is mostly less than 200 mm. Such transitions are savanna forests and savannahs. These types are characterized by summer drought, the duration and intensity of which increases from savanna forests to savannas. At the same time, the summer leaf fall is more and more pronounced. Transitional are also tropical monsoon forests, in which leaf fall occurs in the dry winter months.Savannas are understood as light forests of more or less xerophilous trees and shrubs against the background of a dense, often grassy herbaceous cover. Savannahs occupy vast spaces between rainforests and deserts. In most of these areas, savannas are of a secondary nature, formed in place of forests as a result of the burning of the latter. Such are, for example, in West Africa savannas with oil palm (Elaeis guineensis) and kaya (Khaya from the Melia-ceae family), also growing in forests.Primary savannas are characterized by trees that are absent in dense forests: for example, umbrella-shaped acacias and baobabs, although these same trees can penetrate into secondary savannas. In the campos of South America, cacti grow, pakhira is a tree from the baobab family, etc. However, the South American campos differ from savannas in that they are characteristic of a climate with humid summers and dry winters.The grass cover of savannas consists mainly of tall grasses from the genera Pennisetum, Andropogon, Paspalum, etc. In savannas, the growth of trees is limited by droughts, and partly by displacement by rights. But there are also types of savannas where trees are oppressed by poor soil aeration. This is observed in the conditions of lowered plains with shallow groundwater and heavy soils. Thus, savannahs are connected by transitions with swampy places, sometimes bearing specific forest vegetation.Termite savannas are a special type. Where there are patches of moist forest among the grass thickets, the latter is often exposed to termites (Africa) or leaf cutter ants ( tropical America). These insects loosen the soil, which becomes well air and water permeable, and the forest itself acquires a specific composition. V East Africa these forest islets on termite hillocks are cut down and reclaimed for farming, while the surrounding savannah is used as pasture.Frequent fires in savannahs, both from human burning and from the action of lightning, are exacerbated by droughts. Fires, periodically repeated over the centuries, contributed to the selection of fire-resistant trees and shrubs: dropping foliage or stiff-leaved. In savannas, there are also places where there are no trees at all in large areas; but even such savannas differ from the steppes of a temperate climate by a different seasonal rhythm; the savannas do not have winter rest and, conversely, in the period corresponding to our winter, the grass in the savannas turns green, while in the dry season it acquires fawn tones.Savannah soils are quite varied: from lateritic red soils of drier savannas to black soils of periodically flooded areas. Annual precipitation ranges from 400 to 1500 mm, with an extremely uneven distribution over the seasons. Annual precipitation above 1200 mm is characteristic of secondary savannas, which have taken places from under the forest under the influence of man.True, their numbers began to decline significantly as a result of human extermination, but the large nature reserves that were subsequently organized again began to contribute to its increase. For example, in the South African reserve more than 10 years ago there were up to 40,000 antelopes, up to 500 lions, up to 250 elephants, about 200 giraffes and more than 100 hippos, 500 buffaloes, and now there are probably even more animals there.Here is an excerpt from the essay of the English explorer Anthony Smith, who visited another African nature reserve in the area a long time ago extinct volcano Ngoro-ngoro: Just now, meeting elephants with white tusks, observing families of baboons and looking out for leopards, we were driving through the Leran forest. Suddenly a lake opened up in front of us. And thousands of flamingos, slowly stepping out at an angular step, amicably dip their heads into the water and filter the silt with their beaks.And beyond the lake, around the source of Goitokitok, there is an impenetrable swamp, the kingdom of hippos. The edge of the marsh, with its dense grass, was to the liking of the rhinos. These warlike heavyweights often attack cars ... Having risen from the puddle in which he basked, the rhino looks straight at the intruder. The tail sticks up, nostrils move, drawing in air, and an ancient primitive thought swarms in the skull. When Douglas met such a rhinoceros, he formulated it very well: to beat or not to beat? .. Typical psychology of the Jurassic period ...We will touch upon the deserts of the tropics below when considering the vegetation of the subtropics, since tropical and subtropical deserts are in many ways similar.Along the rivers, both in the savannah zone and in the desert zone, gallery forests stretch, flooded in floods. Their composition is different; in the tropical and subtropical deserts In Africa and Asia, tree-like tamarisks, Arabian acacia, etc. grow in gallery forests. In the savannah zone, these riverside forests are abundant with palms, bamboos and many others. dr.A special type of woody vegetation is represented by thickets of mangroves, characteristic of the tropics of Asia and Africa, and America. These thickets are confined to the viscous, silty saline soils of the sea coasts, periodically flooded with tides. The basis of thickets in both the Old and New Worlds is formed by the species of rhizophora, laguncularia, etc. Rhizophora is remarkable for its adventitious support roots, hanging from the branches vertically down and rooting deep in the viscous soil, which gives the tree stability during high tides.Another feature of the rhizophora is the germination of the seed inside the fruit on the mother plant, and the seedling thus remains on the mother plant for up to six months or more. Then, falling out of the fruit, the seedling sticks its root into the ground and thanks to this it immediately takes root quite deeply. Laguncularia and avicennia have respiratory roots sticking up from the silt, on the surface of which a loose, airy respiratory tissue - aerenchyma - is developed.Various transitions from humid tropical forests to mangroves, to savannas and marshes, to deserts and to various types of mountain forests and shrubs are shown in an interesting diagram by A.G. Voronov (1969), who conducted geobotanical studies in the Republic of Cuba on the islands of Cuba and Pinos. This scheme is built according to the method of ecological-phytocenotic series V, N. Sukachev (see the chapter Geobotany and forestry, but there are more series in it than in Sukachev's, and it covers communities of different classes of formations and even different types vegetation).This scheme shows seven ecological-phytocenotic series, namely: I - flowing soil moisture, II - stagnant moisture, III - moisture and simultaneously salinization of the soil, IV - an increase in the relative humidity of the air, coupled with a decrease in temperatures when climbing mountains, IVa - the same, but on poorer soils and at lower altitudes above the p-sea, V - an increase in the dryness of the air and substrate while maintaining tropical temperatures, VI - the same at subtropical temperatures. In this scheme have found their place, for example: nephelogyny or mountain foggy tropical and subtropical forests, which fell into the IV row; deserts with thorny bushes and cacti, which are the extreme member of the V row; pine forests bands of fog and some other communities of pine forests, etc. The central place in this scheme is occupied by humid (rain) tropical forests, from which the aforementioned seven rows diverge in different directions, forming not a cruciform (like Sukachev's), but rather a fan-shaped figure ...There are a lot of plants cultivated in humid and semi-humid tropics, but this is not our task. Almost the first place belongs to the coconut palm, currently unknown in the wild, but only in cultivated or feral / The oil palm, which also yields valuable oil, is native to West Africa. The African coffee tree and the American chocolate tree are now widely cultivated in the tropics of the Old and New Worlds, as well as the American hevea and cinchona trees.We also note bananas from the Old and pineapple from the New World, and cassava (Manihot utilissima). This last one is a three avanaceous plant from the Euphorbia family. Cassava forms large root cones that are used to prepare flour and other food products. The homeland of cassava is tropical America, but in culture it also spread widely in the tropics of Africa and Asia. The culture of sugar cane (Saccharum officinarum), especially intensive on the island, is of great importance. Cuba, home to extensive pineapple plantations.The climatic zones of the subtropics (there are two of them: in the northern and southern hemispheres) are transitional between the tropics and temperate zones. The climatic limits of the subtropics are quite wide: the average temperature of the coldest month is from + 13 ° to -5 ° C, the absolute minimum temperature is from 0 ° to -20 °. However, such low temperatures, approaching -20 °, are, of course, not in all subtropical regions, in most cases the temperature drops are less significant.Yes, and where they are still strong, as, for example, on our Black sea coast, they are very short-lived. In my memory, a case when in the mountains. Makharadze and its environs in the thirties frost was -19 °, but before that a lot of snow fell and all tea plantations were protected by a snow cover. Moreover, this frost did not last very long, so that the palms and tangerine trees, covered with mats, did not have time to noticeably suffer.In humid subtropics, the average temperature of the coldest month is +4 + 10 °, annual precipitation is 1500-4000 mm, droughts are not pronounced. These include: most of the (southern) Black Sea coast of the Caucasus, the islands of Japan, the southeastern states North America and others, and in the southern hemisphere - southeastern coastal area Cape region, a number of areas in South America, in the southern half of Australia and in New Zealand,In Colchis (the Black Sea coast of the Caucasus), humid subtropics in the mountains reach 600-700 m above sea level. Wild vegetation is represented here mainly deciduous forest with evergreen underbrush. In the tree layer: oriental beech, chestnut, hornbeam, two types of oak, alder, cherry laurel in the undergrowth, Pontic rhododendron, holly, etc. On the edges and clearings dense tents are formed by the thorny liana sassaparilla. In the clearings there are thickets of bracken ferns and blackberries. The soils of these forests are red earth.Although the species composition of trees in the humid subtropical Colchis forest is much poorer than in the forests of the humid tropics, it is still difficult to distinguish associations in it because of the very diverse combinations of these five species, both among themselves and with the undergrowth and ground cover. There are no associations at all, but only macro-associations, as units of complexes of unstable groupings. However, it would be more correct to refer these relatively unstable groupings to associations, but not to nodal ones, and to emphasize the predominance of continuity (continuum) between them over discontinuity (discreteness). The key point here will obviously be their entire complex, that is, the macro-association.There are few such macroassociations in the Colchis multi-breed forest, and they have very large areas covering whole woodlands... The main, the most common of them are three:
1) normal with the participation of all the listed tree species and significant development of evergreen undergrowth;
2) dryish with a weak participation of evergreen shrubs, but with an abundance of deciduous azalea in the undergrowth ;
3) gorge, usually without oak, but with an admixture of lapina, persimmon and beautiful maple.In the southeastern states of North America (east of the Mississippi River, between 30 and 40 ° N latitude), in hardwood forests: oak, maple, linden and others, there is a tulip tree, white acacia and a magnificent evergreen magnolia with large fragrant white flowers, widely cultivated on our Black Sea coast. There are many trees of the second size and shrubs, both evergreen and deciduous. In some places there is a small admixture of conifers: Weymouth pine, hemlock, etc. Such are the forests in the southern part of the Appalachian Mountains. The southern part of Florida already has a tropical climate.Subtropical humid forests form a vertical belt over tropical rainforest in those mountainous countries that lie in tropical latitudes. Such are, for example, the subtropical forests of the vicinity of Darjeeling, in the Himalayas, located at altitudes from 1600 to 2200 m and slightly higher. These forests consist of a mixture of deciduous and evergreen species, including conifers. Several types of treelike rhododendrons are very characteristic.The most characteristic plants cultivated in the humid subtropics are the tea bush and citrus fruits. The tea bush also occurs wildly in the humid subtropics of Asia, like an undergrowth in forests, while cultivated citrus species in the wild are unknown. They are probably the product of a very ancient culture.The Mediterranean subtropics, while similar to the humid subtropics in winter temperatures, differ from them in a pronounced summer drought with a total annual precipitation of 600-1200 mm. The Mediterranean subtropical climate is found not only on the Mediterranean coast, but the latter is the most typical in this respect. In addition to southern France, southern Italy, northern Algeria, Dalmatia, Greece, etc., the Mediterranean climate is expressed in the central and eastern regions of California, on the southern coast of Crimea, etc.This climate is very pronounced on the islands of the Mediterranean Sea and the closest part of the Atlantic Ocean, such as Cyprus, Crete, Corsica, Mallorca, Madeira, etc. In the southern hemisphere, the Mediterranean subtropics are expressed in the southwestern part of the Cape region, in some areas of the South American Andes (Chile) and the southern half of Australia.Above the belt of maquis and evergreen oaks, chestnut forests are found in many parts of Middle-earth. We also have them, having been described from the Sochi region, which lies at the junction of the humid-subtropical climate of Colchis and the Anapa-Novorossiysk region, which is transitional to the Mediterranean climate. In California, chaparelli is formed by evergreen shrubs and trees, with an admixture of deciduous ones. There is also a species of evergreen oak (Q. agrifolia).On very rocky slopes, devoid of a continuous soil cover, there are sparse thickets of small narrow-leaved, xerophilous shrubs and semi-shrubs. These are the formations: gariga (mainly from evergreen forms), frigana (from a variety of xerophytes with the participation of pillow plants) and tomillara (with a predominance of odorous labiates). Under the influence of felling, burning and grazing, these xerophilic formations expand their areas at the expense of maquis.Of the conifers for the wild flora of the Mediterranean subtropics, Italian pine or pine, Aleppo pine, species of junipers, in Algeria, Atlas cedar, a peculiar coniferous Callitris, etc. are characteristic. on seaside rocks, taking root in their cracks.In the south of Spain, there is a wild dwarf fan palm. This is the only wild palm tree in Europe. It is found in large low clumps among a kind of subtropical steppe on the plain. And for Cape Gibraltar, Bram mentioned the magot monkeys from the macaque breed living there wildly on the rocks. There is a legend about these monkeys that they crossed to Gibraltar from Africa through a tunnel that supposedly existed or existed under Strait of Gibraltar... However, if we compare them with the thickets of wild palms in southern Spain, with cork oak forests in Spain and northern Africa, then the magot monkey will easily fit into these biogeocenoses and interest in the legend about its passage under the sea will disappear.On the southern coast of Crimea, evergreen vegetation is represented by juniper (Juniperus excelsa) and pine (Pinus pallasiana), there is no maquis, but only individual deciduous evergreens: strawberry tree, Pontic butcher and semi-evergreen cistus (Cistus tauricus).Of the plants specially cultivated in the Mediterranean subtropics, let us name the olive, or the olive, the carob, or the Constantinople horns; in addition - tobacco, grapes, oranges, lemon, grain crops, etc. Orange and lemon work best in a Mediterranean climate, and mandarin in a humid subtropical climate. The most characteristic tree cultivated throughout the Mediterranean subtropics is the pyramidal cypress (Cupressus sempervirens), whose dark olive-black crowns create a remarkable beauty of the landscape in contrast to the greenery, coastal cliffs and the sea.In the southern half of Australia, areas with a Mediterranean-type climate are characterized by light forests of equalipts with a variety of more or less xerophilous trees and shrubs in the undergrowth. Among them are acacia, proteaceous and many others. other. There are also thickets of shrubby eucalyptus.As an example of a region transitioning from Mediterranean subtropics to humid subtropics, let us call Talysh, covering the Lankaran and Astara administrative regions of the Azerbaijan SSR. In terms of annual precipitation, Talysh is slightly inferior to Colchis, but has a rather pronounced drought in the second half of summer. The neighboring Iranian provinces are similar to Talish: Gilan and Mazandaran.Subtropical climate, and in Talysh there is a vast Caspian wooded lowland and the lower belt of mountains. Deciduous forests are developed here with the participation of chestnut oak, zelkova, ironwood, majestic maple and other original species. The undergrowth is mostly deciduous, but it also contains several evergreen species. Tea and citrus fruits are successfully cultivated in Talysh, but tea in the state of young shoots requires shading. Large areas are occupied by rice fields(challtyks).Talysh is a very peculiar area by nature. In it, and the animal world bears the imprint of the tropics, for example, a black humped breed of a domestic bull, the so-called zebu, is widespread there. At the beginning of this century, tigers were found in Talysh. By the way, there was a case of a tiger appearing in 1928 in a wooded gorge not far from Tbilisi. He was killed, and his effigy is on display in the local history museum. It is believed that he entered from Iran, moving along the riverine thickets, first of the Araks River, and then of the Kura.While the Mediterranean subtropics are characterized by wet winters and dry summers, the monsoon subtropics, on the contrary, are characterized by moisture in the warmer seasons and aridity in the cooler ones. Some areas of India, China and Korea have a monsoon, subtropical climate. In Burma, subtropical monsoon forests are formed by some magnolia, laurel, oak, and others with rhododendrons in the undergrowth.In southern Brazil, the monsoon subtropics are characterized by two formations, which are distributed depending on soil and geomorphological features: forests of araucaria and subtropical steppes - pampas. Nai large areas However, the pampas are covered in Argentina, where in the northern part they are located in the monsoon subtropical region, and further to the south - in the monsoon temperate climate.In the pampas, cereals from the genera Pas-palum, Panicum, Andropogon, Stipa, Aristida, etc. prevail. Thus, the pampas differ from the savannas not only by the absence of trees, but also by a different seasonal rhythm: in the savannas, the dry period is the hottest, and in the pampas he is the coolest. In this last feature, the pampas are similar to the campos. The pampas are used as rich pastures, large areas of them are plowed up and are occupied with crops of wheat and corn.The dry subtropics and tropics include areas with an annual rainfall of less than 400 mm, and according to the temperature regime, they are subtropical and tropical. The main types of vegetation cover in these areas are as follows.In deserts, precipitation is not more than 200 mm, and there are deserts that are almost completely rainless. The vegetation forms an open cover or is represented by separate, scattered specimens. The predominant life form is half-shrubs (for example, wormwood), small shrubs (for example, from hodgepodge, from Juz-gun - Calligonum), sometimes even trees (saxaul). The participation of annual ephemera is also noticeable, for the most part by the beginning of summer they are already seeding and dying off. By the nature of the substrate, deserts are divided into sandy, stony, clayey, saline. The sandy expanses of the Sahara are completely devoid of plants for a large extent, this applies mainly to the southern part of the Sahara, which lies in an area of tropical climate.Mainly in the northern part of the Sahara, lying in the subtropical region, wadis are abundant in places, that is, dry stony beds of former channels - witnesses of a less dry past. These wadis often have sparse vegetation, while the surrounding areas may be devoid of plants. In the USSR, the largest areas of deserts are located in Central Asia, where they are mostly subtropical in nature, as well as in the southeast of Transcaucasia. V Astrakhan region deserts lie in an area of temperate climate.In Central Asia, wormwood deserts prevail on clayey soils, and on the sands of the desert with juzgun, and in places with sandy acacia (Ammodendron) and saxauls. In Southeast Transcaucasia, there are wormwood deserts (Artemisia fragrans Willd.) And saltwort deserts (Salsola dendroides Pall.). On the plateau of Northwestern Mexico and Southern California, there are deserts and semi-deserts with cacti, agaves, yuccas, and in the deserts of Southwest Africa - the famous vel-aichia.Here there are giant cereus, the height of which reaches 15 meters or more, and tiny mamillaria and especially blessfeldia - the size of a 10-kopeck coin. There are also many prickly pears and echinocactus common in our room culture. By the way, the prickly pear was brought to Italy and Spain, where in some places it ran wild, turning into an annoying weed that forms dense thorny thickets.One of the species of prickly pears grows wild in Kabardino-Balkaria (North Caucasus). Here prickly pear grows as part of the wormwood-bearded steppe, A. Kh. Kushkhov (1969) writes that arable land is coming closer to this place every year and therefore it is necessary to take measures to protect this unique site. Here the difference in climates affects: in the subtropics of southern Italy, prickly pear is a malicious weed, from which it is necessary to protect cultivated crops, and in the North Caucasus in a moderately warm climate, the prickly pear itself has to be protected from cultivated crops.Semi-deserts are characterized by the fact that perennial turf grasses are mixed with the main background of xerophilic dwarf shrubs, most often wormwood: feather grass, fescue, bearded vulture, etc. Semi-deserts are found both in subtropical and temperate climates with an annual precipitation of 200-350 mm. There are subtropical semi-deserts in Central Asia, the Caucasus, and North Africa.The subtropical dry steppes, in contrast to the Pampas, have the coincidence of the driest and hottest seasons. At the same time, the winter period of dormancy in Niki is weakly expressed or absent altogether, in contrast to the steppes of temperate and temperate climates. The subtropical steppes include the steppes of the alpha-alpha grass (Stipa tenacissima) of North Africa, the 6o-roach steppes (Andropogon ischaemum) of Central Asia and the Caucasus, and some others.Freegans are characteristic of rocky slopes with no complete soil cover and are found in both dry subtropical and Mediterranean and warm temperate climates. The Megri frigana described above is found partly in a dry subtropical, partly in a moderately warm climate. It is formed by various life forms of plants: semi-shrubs, small shrubs, turf grasses, and others, but all of them are united by extreme xerophilicity. This vegetation does not form a closed cover. Freegan is primary and secondary; the latter arises in places of forest or shrub vegetation as a result of felling and grazing, which is accompanied by soil erosion with exposure of stone rocks in the conditions of mountain slopes.Secondary freegang, formed in the place of juniper (juniper) light forests, as well as in places of deciduous xerophilous open forests from the carcass (Celtis caucasica Willd,), pistachios (Pistacia militica), wild figs and pomegranates, covers in places steep rocky slopes in South Transcaucasia. Freegan is most widespread in Central Asia, Southeast Transcaucasia, Dagestan, as well as in the countries of Western Asia (Iraq, Syria, etc.).While on the steep slopes of the mountains, xerophilic light forests are less stable and are easily replaced by frigans in the conditions of a soft hilly relief, they have survived over large areas. Such are the woodlands with the Wild Pistachio in Central Asia, where the cereal cover is well developed. Sometimes they are called half-savannah (Ovchinnikov) or even savannah (Linchevsky). Somewhat resembling xerophilous light forests and, to a greater extent, even to a frigan, groups are found in the Cape region (South Africa). They also occupy rocky slopes, where they form an open cover, but their feature is the rather significant role of succulents, such as Mesembrianthemum, cactus euphorbia, aloe, etc.The main cultivated plants of dry subtropics: cotton almonds, mulberries (mulberries), walnuts, figs, pomegranates, peaches, apricots, and grapes. However, mulberries, peaches, apricots, grapes, walnuts also go beyond the subtropics, being widespread in culture and in temperate climates.Tropical and partly subtropical deserts are characterized by culture date palm, confined to oases where groundwater is shallow. The date palm is said to have its head on fire and its feet in water. This means that it can tolerate a lot of heat and dry air, but its roots must be provided with water.In the USSR, the date palm culture was tested (in Turkmenistan), but it did not develop, since our subtropics were not warm enough for it. In some areas, such as in the deserts of Iraq and southern Iran, dates are the staple food of the rural population, and they are even ground in dried form into flour, from which bread cakes are baked.Just as there are such date villages in Iraq and southern Iran, some villages in Afghanistan are mulberry, since the main food product in them is the fruits (more precisely, the fruit) of the mulberry tree (mulberry), which are also used there to make bread cakes. And in Abyssinia they bake pancakes from figs.
Oases, as well as narrow strips of gallery forest along the rivers, enliven the monotonous desert landscape. Wormwood deserts as well as semi-deserts serve as pastures, especially for sheep and camels.
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