) a zone represented by more or less densely growing trees and shrubs of one or more species. The forest has the ability to constantly renew itself. Mosses, lichens, herbs, and shrubs play a secondary role in the forest. Plants here influence each other, interact with the environment, forming a commonwealth of plants.
A significant area of forest with more or less clear boundaries is called a forest area. There are the following types of forests:
gallery forest. It is stretched out in a narrow strip along the river, flowing among treeless spaces (in Central Asia it is called the tugai forest, or tugai);
Tape bur. This is the name of pine forests growing in the form of a narrow and long strip on the sands. They are of great water conservation importance, their felling is prohibited;
park forest. This is an array of natural or artificial origin with rare, singly scattered trees (for example, a park forest of stone birch in Kamchatka);
copses. These are small forests connecting woodlands;
Grove- a piece of forest, usually isolated from the main massif.
The forest is characterized by layering - the vertical division of the forest massif, as it were, into separate floors. One or more upper tiers form the crowns of trees, then come the tiers of shrubs (undergrowth), herbaceous plants, and finally the tier of mosses and lichens. The lower the tier, the less demanding of light are the species that make it up. Plants of different tiers closely interact and are mutually dependent. The strong growth of the upper tiers reduces the density of the lower ones, up to their complete disappearance, and vice versa. There is also underground layering in the soil: the roots of plants are located here at different depths, so numerous plants coexist well in one area. Man, by regulating the density of crops, forces the development of those tiers of the community that are valuable for the economy.
Depending on climatic, soil and other natural conditions, various forests arise.
This is a natural (geographical) zone stretching along the equator with some shift to the south from 8° north latitude. up to 11°S The climate is hot and humid. All year round, average air temperatures are 24-28 C. The seasons are not pronounced. At least 1500 mm of precipitation falls, since here is an area of \u200b\u200blow pressure (see), and on the coast the amount of precipitation increases to 10,000 mm. Precipitation falls evenly throughout the year.
Such climatic conditions of this zone contribute to the development of a lush evergreen forest with a complex longline structure. The trees here have little branching. They have disc-shaped roots, large leathery leaves, tree trunks rise like columns and spread their thick crown only at the top. The shiny, as if varnished surface of the leaves saves them from excessive evaporation and burns from the scorching sun, from the impact of rain jets during heavy showers. In plants of the lower tier, the leaves, on the contrary, are thin and delicate.
The equatorial forests of South America are called selva (port. - forest). This zone here occupies much larger areas than in. The selva is wetter than the African equatorial forests, richer in plant and animal species.
The soils under the forest canopy are red-yellow, ferrolitic (containing aluminum and iron).
equatorial forest- the birthplace of many valuable plants, such as oil palm, from the fruits of which palm oil is obtained. The wood of many trees is used to make furniture and is exported in large quantities. These include ebony, the wood of which is black or dark green. Many plants of the equatorial forests provide not only valuable wood, but also fruits, juice, bark for use in technology and medicine.
Elements of equatorial forests penetrate into the tropics along the coast of Central America, on.
The main share of equatorial forests is located in Africa and South America, but they are also found in, mainly on the islands. As a result of significant deforestation, the area under them is sharply reduced.
hardwood forests
Hardwood forests are developed in Mediterranean climates. It is a moderately warm climate with hot (20-25°C) and relatively dry summers and cool and rainy winters. The average amount of precipitation is 400-600 mm per year with rare and short-lived snow cover.
Basically, hardwood forests grow in the south, on, in the southwest and southeast. Separate fragments of these forests are found in America (, Chile).
They, like the equatorial forests, have a tiered structure with lianas and epiphytes. In hard-leaved forests there are oaks (holm, cork), strawberry tree, wild olives, heather, myrtle. Hard-leaved are rich in eucalyptus. Here there are giant trees, more than 100 m high. Their roots go 30 m into the ground and, like powerful pumps, pump moisture out of it. There are stunted eucalyptus trees and shrub eucalyptus trees.
Plants of hardwood forests are very well adapted to the lack of moisture. Most have small gray-green leaves obliquely arranged in relation to the sun's rays, and the crown does not obscure the soil. In some plants, the leaves are modified, reduced to thorns. Such, for example, are scrubs - thickets of prickly bushes of acacias and eucalyptus trees. Scrubs are located in Australia, in areas almost devoid of and.
The fauna of the zone of hard-leaved forests is also peculiar. For example, in the eucalyptus forests of Australia, you can meet the koala marsupial bear. It lives in trees and leads a sedentary nocturnal lifestyle.
The climatic features of this zone are favorable for the growth of deciduous trees with a wide leaf plate. Moderately continental bring precipitation from the oceans (from 400 to 600 mm), mainly in the warm season. The average temperature in January is -8°-0°С, in July +20-24°С. Beech, hornbeam, elm, maple, linden, and ash grow in the forests. The deciduous forests of eastern America are dominated by trees similar to some of the East Asian and European species, but there are also species that are unique to this area. In terms of composition, these forests are among the richest in the world. Most of all in them are American species of oaks, along with them chestnut, linden, plane trees are common. Tall trees with a powerful, spreading crown predominate, often entwined with climbing plants - grapes or ivy. To the south, magnolias and a tulip tree can be found. For European broad-leaved forests, oak and beech are the most typical.
The fauna of the broad-leaved forests is close to the taiga, but there are some animals that are unknown in the forests. These are black bears, wolves, foxes, minks, raccoons. A characteristic hoofed animal of deciduous forests is the white-tailed deer. It is considered an undesirable neighbor for settlements, as it eats young crops. In the deciduous forests of Eurasia, many animals have become rare and are under human protection. The bison and the Ussuri tiger are listed in the Red Book.
Soils in deciduous forests are gray forest or brown forest.
This zone of forests is densely inhabited and largely reduced to nothing. It has survived only in heavily rugged, inconvenient areas for arable farming and in reserves.
Mixed temperate forests
These are forests with various tree species: coniferous-broad-leaved, small-leaved, small-leaved-pine. This zone is located in the north of North America (on the border with the USA), in Eurasia, forming a narrow strip lying between the taiga and the zone of broad-leaved forests, in the Far East. The climatic features of this zone differ from the zone of broad-leaved forests. The climate is temperate, with increasing continental towards the center of the mainland. This is evidenced by the annual amplitude of temperature fluctuations, as well as the annual amount of precipitation, which varies from oceanic regions to the center of the continent.
The diversity of vegetation in this zone is explained by differences in climate: temperature, amount of precipitation and the mode of precipitation. , where precipitation falls all year round due to westerly winds, European spruce, oak, linden, elm, fir, beech are common, that is, coniferous-deciduous forests are located here.
In the Far East, where precipitation is brought only in summer by monsoons, mixed forests have a southern appearance and are distinguished by a wide variety of species, many layers, an abundance of lianas, and mosses and epiphytes on trunks. In deciduous forests, pines, birches, aspens with an admixture of spruce, cedar, and fir predominate. In North America, the most common conifers are white pine, reaching a height of 50 m, and red pine. Of the hardwoods, birch with yellow hardwood, sugar maple, American ash, elm, beech, and linden are widespread.
The soils in the zone of mixed forests are gray forest and sod-podzolic, and in the Far East they are brown forest. The animal world is similar to the animal world of the taiga and the zone of deciduous forests. Elk, sable, brown bear live here.
Mixed forests have long been subjected to severe deforestation and fires. They are best preserved in the Far East, while in Eurasia they are used for field and pasture land.
Taiga
This forest zone is located within the temperate climate in the north of North America and in the north of Eurasia. There are two types of taiga: light coniferous and dark coniferous. Light coniferous taiga is the least demanding pine and larch forests in terms of soil and climatic conditions, the sparse crown of which transmits the sun's rays to the ground. Pine forests, having a branched root system, have acquired the ability to use nutrients from marginal soils, which is used to fix the soil. This feature of the root system of these forests allows them to grow in areas with. The shrub layer of the light coniferous taiga consists of alder, dwarf birch, polar willow, and berry bushes. Under this tier are mosses and lichens. It is the main food for reindeer. This type of taiga is common in.
Dark coniferous taiga are forests represented by species with dark, evergreen needles. These forests consist of numerous species of spruce, fir, Siberian pine (cedar). The dark coniferous taiga, unlike the light coniferous one, does not have an undergrowth, since its trees are tightly closed by crowns, and it is gloomy in these forests. The lower tier is made up of shrubs with hard leaves (lingonberries) and dense ferns. This type of taiga is common in the European part of Russia and Western Siberia.
The peculiar flora of these types of taiga is explained by differences in territories: and quantity. The seasons are clearly distinguished.
The soils of the taiga forest zone are podzolic. They contain little humus, but when fertilized they can provide a high yield. In the taiga of the Far East - acidic soils.
The fauna of the taiga zone is rich. Numerous predators are found here - valuable game animals: otter, marten, sable, mink, weasel. Of the large predators, there are bears, wolves, lynxes, wolverines. In North America, bison and elk deer used to be found in the taiga zone. Now they live only in reserves. The taiga is rich in rodents. Of these, the most typical are beavers, muskrats, squirrels, hares, chipmunks, and mice. The taiga world of birds is also very diverse: nutcrackers, thrushes, bullfinches, capercaillie, black grouse, hazel grouses.
Tropical forests
They are located along the east of Central America, in the Caribbean islands, on the island, in the east of Australia and in the southeast. The existence of forests in this dry and hot climate is possible due to the heavy rainfall that is brought by the monsoons in summer from the oceans. Depending on the degree of moisture, tropical forests are divided into permanently humid and seasonally humid forests. In terms of their species diversity of flora and fauna, humid tropical forests are close to equatorial forests. These forests contain many palms, evergreen oaks, and tree ferns. Many vines and epiphytes from orchids and ferns. The tropical forests of Australia differ from others in the relative poverty of the species composition. There are few palms here, but eucalyptus, laurels, ficuses, legumes are often found.
The fauna of the equatorial forests is similar to the fauna of the forests of this belt. The soils are mostly lateritic (lat. later - brick). These are soils, which include oxides of iron, aluminum and titanium; they are usually reddish in color.
Forests of the subequatorial belt
These are deciduous evergreen forests that are located along the eastern outskirts of South America, along the coast, in northeastern Australia. Two seasons are clearly expressed here: dry and wet, the duration of which is about 200 days. In summer, equatorial humid air masses dominate here, and in winter - dry tropical air masses, which leads to the fall of leaves from trees. constantly high, +20-30°С. Atmospheric precipitation decreases from 2000 mm to 200 mm per year. This leads to a lengthening of the dry period and to the change of evergreen permanently wet forests by seasonally wet deciduous ones. During the dry season, most deciduous trees do not shed their entire foliage, but few species remain completely bare.
Mixed (monsoon) forests of the subtropical belt
They are located in the southeastern United States and eastern China. These are the wettest of all zones of the subtropical belt. Characterized by the absence of a dry period. Annual rainfall is greater than evaporation. The maximum amount of precipitation usually falls in the summer, as the monsoons bring moisture from the oceans, the winter is relatively dry and cool. Inland waters are quite rich, groundwater is mostly fresh, with a shallow occurrence.
Here, tall mixed forests grow on brown and gray forest soils. Their species composition may vary depending on soil conditions. In the forests you can find subtropical species of pines, magnolia, camphor laurel, camellia. On the flooded coasts of Florida (USA) and on the lowlands, cypress forests are common.
The zone of mixed forests of the subtropical zone has long been mastered by man. In the place of reduced forests in America, there are field and pasture lands, orchards, and plantations. In Eurasia - forestry lands with areas of field lands. Rice, tea, citrus fruits, wheat, corn and industrial crops are grown here.
The abundance of heat and moisture in the Malay Archipelago contributed here to the dominance of moist equatorial forests on red-yellow ferralitic soils, which are only replaced in places by monsoon forests and savannahs. The flora of these rainforests includes 23 thousand flowering plants, of which 2.5 thousand are trees. Representatives of the dipterocarp family (200 species) predominate, palm trees (70 species), ferns (400), bamboos (70), orchids (700 species) and others are numerous. Equatorial forests cover mountains up to a height of 1200-1300 m. shady, without undergrowth, with rich extra-tiered vegetation - lianas and epiphytes. The general species diversity is dominated by palms (palmyra, sago, sugar, rattan, etc.), dipterocarps, bamboos, tree ferns, ficuses, pandanuses, and wild bananas. Above 1200 m, representatives of the subtropical (oaks, conifers) and boreal (chestnuts, maples, etc.) floras appear and then dominate. At an altitude of 2500-2600 m, they are replaced by a zone of shrubs with some conifers (mountain casuarina). Above, the belt of shrubs is replaced by alpine meadows, and behind them is a belt of eternal snows. With increasing dryness in the monsoon forests, the role of deciduous trees (teak) and shrubs (acacia) intensifies. Small groups of trees grow in shrouds among tall grasses (wild sugarcane, alang-alang). On the Lesser Sunda Islands, there are many representatives of the Australian flora (eucalyptus, spinifex, casuarina, etc.). The fauna of the humid equatorial forests is also rich and varied: more than 200 species of mammals, 600 birds, 100 snakes, 1000 butterflies. An orangutan and narrow-nosed monkeys (gibbons, monkeys, etc.) live here. There are elephants, rhinos, black-backed tapirs, anua buffalo, babirussa pig, predatory tiger, sun bear. Diverse birds (paradise, hornbills) and reptiles (Komodo lizard). The fauna is gradually changing from the northwest to the southeast. At first, the orangutan, the rhinoceros, then the typical ungulates disappear. Some elements of the Australian fauna, mainly birds, appear on the Lesser Sunda Islands. Thus, the Malay Archipelago has features inherent in Eurasia and Australia, and is a kind of bridge connecting both continents (Lavrinovich, 2004). In addition to zonal vegetation, non-zonal communities are widely represented in Eurasia: meadows, swamps, and mangroves. Meadows and swamps are quite well known to the population of Belarus. Mangroves are halohydrophilic vegetation on periodically flooded silty sea coasts and estuaries in the subequatorial and equatorial belts of the mainland. Their species composition is not rich in about 50 species of palm trees (nipa, rhizophora, avicenia, brugiera, etc.). Animals are adapted to live in two environments - air and water-silt. The crowns of the trees are inhabited by parrots and monkeys. Numerous insects (dragonflies, mosquitoes, etc.). Significant territories of Eurasia are occupied by mountain systems with altitudinal zonality, the analysis of which will be made during the regional review of this continent.
Equatorial forests are considered one of the most ancient natural areas. They are common in the equatorial regions of Africa, from where they got their name. In addition to the African continent, the equatorial forest is found in the Indonesian islands, in the Amazon, in northern Australia and in the southern regions of the Malay Peninsula, and covers 6% of the entire surface of the Earth.
Moist equatorial forests on the map of the World.
Moist equatorial forests grow in peculiar "spots", most often in lowland areas. Their main feature is the lack of change of seasons, that is, the weather here is stable - hot, humid and rainy all year round. Because of this, the second name of the equatorial forests is rainforests.
The climate of the equatorial forests
The climate of the equatorial forests is characterized by high humidity, usually 85%, approximately the same air temperature and intense precipitation. The average daytime temperature is around 28ºC, at night the temperature can drop below 22ºC.
There are two main seasons in this natural area: dry season and heavy rainy season. The dry season lasts from July to September. For the year in the equatorial forest falls from 250 cm to 450 cm of precipitation. Strong gusts of wind in the equatorial forest are almost never observed.
Such climatic conditions of the equatorial forest led to the rapid growth of vegetation, due to the density of which the equatorial forests are still difficult to pass and little explored.
Answering the question of what contributes to the formation of such a climate, we can say that the main factor is the location. The equatorial forest is located in the intratropical convergence zone. This is a zone with relatively low atmospheric pressure and weak winds of variable directions.
In addition, the feedback between convection processes and high levels of soil moisture, along with the interception of precipitation from dense vegetation, leads to transpiration. This feedback leads to a daily recurring climate pattern: hot, humid air, dry but foggy mornings, evening showers, and convective storms.
Plants of the equatorial forests
Life in the equatorial forests is distributed “vertically”: plants inhabit the space in several levels, the number of so-called floors can reach four. Photosynthesis in the zone of humid equatorial forests occurs without interruption all year round.
The flora of the equatorial forest is mainly represented by trees that reach a height of 80 meters and have wide roots that serve not only to support, but also to maximize the absorption of nutrients from poor soil. Trees in rain forests, although deciduous, are mostly related to.
In addition to trees, the equatorial forests are home to many woody vines - climbing plants that can climb to any height in pursuit of sunlight. Creepers twist around trunks, hang on branches, spread from tree to tree, like snakes crawl along the ground in wide twists or lie on it in tangled balls. Some creepers of the equatorial forests have thin, smooth, aerial-like roots, others are rough and knotty. Often creepers are woven together like real ropes. Woody vines have a long lifespan and have an almost limitless ability to grow in length.
Being so varied in length, thickness, hardness and flexibility, the creepers of the equatorial forest are widely used by the natives in their daily life. Almost all rope products are woven from vines. Some vines do not rot in water for a long time and therefore are widely used in the manufacture of ropes, twine for attaching fishing lines and wooden anchors.
In addition to the many species of trees and lianas of which the equatorial forests are mainly composed, various types of palm trees are also widely found here. The middle and lower floors are represented by grasses, mushrooms and lichens, reeds appear in places. Rainforest plants have a lot of leaves, but the higher they are, the smaller the leaves become. Where forests are near the coast, you can find swamps covered with.
Below is a short list of the most famous plants of the equatorial forest:
- cocoa tree;
- Brazilian hevea - a source of rubber from which rubber is made;
- banana tree;
- a coffee tree;
- oil palm, which is the source of palm oil used in the manufacture of soaps, ointments, creams, as well as candles and margarine;
- fragrant zest, from the wood of which cigarette cases are made;
- ceiba. From the seeds of this plant, oil is extracted, which is necessary for soap making, and from the fruits - cotton, which serves as a filler for soft toys and furniture, and is also used for sound and heat insulation.
Animals of the equatorial forests
The fauna of the equatorial forest, like the flora, is located in several tiers. The lower floor is a habitat for insects, including butterflies, small rodents, small ungulates, as well as predators - reptiles and wild cats.
The humid equatorial forests of Africa are inhabited by leopards and African elephants, jaguars live in South America, and Indian elephants live in India, which are smaller and more mobile than their African counterparts. Rivers and lakes are home to crocodiles, hippos and water snakes, including the largest snake on our planet, the anaconda.
Among the diversity of the fauna of the equatorial forests, a large number of birds can be distinguished. These include toucans, sunbirds, banana-eaters, turacos, and hummingbirds. One of the most famous inhabitants of the rain forests is traditionally considered to be parrots of various species. All feathered equatorial forests are united by exotic beauty and bright plumage. Among all this beauty, birds of paradise stand out the most - their multi-colored tufts and tails reach a length of 60 cm.
In the neighborhood with birds on the crowns of trees, sloths and monkeys live: monkeys, howler monkeys, orangutans and others. The crowns of trees are their main place of residence, as there is a lot of food in this tier - nuts, berries and flowers. In addition, this longline provides protection from terrestrial predators and winds. The forest canopy is so dense that it serves as a "superhighway" for arboreal mammals. Large primates - chimpanzees and gorillas - inhabit the lower tier of equatorial forests, where they feed on fruits that have fallen from trees, as well as young shoots and roots of plants.
Soil of equatorial forests
Due to the high content of aluminum and iron, the soils of the equatorial forests have acquired a red-yellow color.
Despite the fact that the equatorial forest is the habitat of a myriad of plant species, the soils of this zone are relatively infertile and poor. The reason for this is the hot climate, due to which plants quickly decompose under the influence of bacteria, which in turn prevents the formation of a fertile (humus) layer. High precipitation in turn leads to leaching, the process of washing out soluble salts and minerals such as calcium and magnesium with water. For millions of years, weathering and heavy rains have led to the loss of soil nutrients. Also, the process of deforestation, which has worsened in the last few decades, has a negative impact on the rapid leaching of the elements necessary for plants.
What is the importance of equatorial forests?
The value of the equatorial forest, both for humanity and for nature in general, cannot be estimated. Equatorial forests are called the "lungs of our planet", as they absorb a large amount of carbon dioxide from the atmosphere, and in return they release a huge amount of oxygen, on which the survival of all living organisms depends.
While the problems of the equatorial forests may seem remote, these ecosystems are critical to our well-being. Equatorial forests stabilize the climate, provide habitat for countless plants and wildlife, and generate and influence precipitation across the planet.
The role of equatorial rainforests:
- help stabilize the world's climate;
- provide a home for many plants and animals;
- maintain the water cycle, protect against floods, droughts and erosion;
- are a source of medicines and food;
- support for the population of the indigenous tribes of the equatorial forests;
- and also they are an interesting place for tourists from all over the world to visit and relax.
Eurasia is the largest continent in the world. This land mass with the islands adjacent to it stretches from the equatorial to the northern polar latitudes. Therefore, the entire set of natural zones is presented here, as well as their various provincial modifications, depending on the remoteness of the region from the ocean or the features of the relief. The giant belt of mountain structures, stretching from the Alps to the Himalayas, has a predominantly latitudinal orientation, so the extent of the geographical zones of Eurasia is close to the classical one. A significant part of the mainland is part of our country, and the zones of its northern half are known to us better than other regions of the globe.
Moist equatorial and tropical forests. Evergreen rainforests and moist (with a short dry season) monsoon forests close to them occupy the equatorial and some tropical regions of Eurasia. The most extensive expanses of typical hyla are found in many places on the Malay Peninsula, on the islands of Sumatra and Kalimantan. In addition, the rainforest and the wettest types of monsoon forests are common in Indochina, India (Assam), Sri Lanka, in some areas of the Western and Eastern Ghats of India, in the foothills of the Eastern Himalayas. In Burma, Thailand, in southern China, seasonally dry monsoon forests predominate, and a real rain forest is represented by small islands. Close to the Indo-Malay rainforest of the western Pacific Islands and the Philippines. New Guinea represents the transition to the Australian rainforest.
The appearance of the Asiatic hyla generally corresponds to what we already know for other continents. Three main tree tiers A, B, and C are also expressed here. Under the canopy of a distinct and sparse tier A, tiers B and C are often difficult to separate from each other (when analyzing profile diagrams). They form a closed canopy entwined with lianas, under which only rare grasses and shoots of trees grow.
In terms of the number of species of woody plants known to science and the overall richness of the flora, the rainforests of Asia surpass the hylae of Africa and even South America. The floral flora of the Malay Archipelago with Malacca and New Guinea has about 20 thousand described species, but in fact there are even more. For only one peninsula of Malacca, figures of 10 thousand species are given. The floristic richness of the Asian humid equatorial forests can also be seen when comparing some characteristic families. So, in the Congo basin, several hundred species of orchids are known, most of them are epiphytes (probably, their number does not exceed 500). For the Malay Archipelago, 5 thousand of these plants are known. About 100 species of trees with a trunk diameter of more than 20 cm were found on one of the test plots of 1.5 hectares among the primary rainforest (Mount Dulit, Kalimantan), and only about 4% of the individuals belonged to one species (according to Richards). Despite the very small proportion of each species in the community, about 17% of all trees with a trunk diameter of more than 20 cm and about 45% of large trees (with a trunk diameter of more than 40 cm) belonged to the dipterocarp family. The latter we especially emphasize, for it is one of the most characteristic features of the humid evergreen forests of Asia: the dominance of trees belonging to this family. Species of dipterocarps especially clearly predominate in the upper layer of A.
As on other continents, polydominant groups of woody plants are most typical. However, in a number of cases, most often under special edaphic conditions (poor leached sands, etc.), groups with a small number of dominant trees in the upper layer predominate. The total number of species on an area of 1 ha is almost half that in typical polydominant communities. Areas dominated by conifers and some dipterocarps are described. It should be noted that at low altitudes, monodominant (and oligodominant) evergreen forests are dominated by dipterocarp species. Forests dominated by the Malayan ironwood are of very great economic value. There are also plantations with a predominance of kapur, or Malay camphor tree, one of the representatives of the dipterocarp. The last tree is characteristic of moist monsoon forests, it sheds foliage for a short time (most of the trees, especially low ones, remain evergreen). The semi-evergreen forests of Asia are also characterized by an abundance of vines and epiphytes. Often they have a lot of bamboo and small palm trees. For most of the year, these forests are almost indistinguishable from typical rainforests. They are similar not only in the structure of the vegetation cover and floristic richness, but also in the characteristics of the fauna and animal population. For many groups of animals, the differences between them are even smaller than for vegetation.
As in other regions of the globe, among the animals of the Asiatic hyla, arboreal forms are abundantly represented. Termites predominate in the ground and soil layers. These insects, together with ants, are the most visible of all animals, either directly or by the traces of their activity. As in other humid equatorial and tropical latitudes, hygrophilous invertebrates and amphibians living in the air are numerous in Asia. In particular, ground forest leeches from the genus Hamadips are very annoying in places. As on other continents, such groups of insects as crickets, cockroaches, cicadas, earwigs, bronze beetles and other beetles, brentids, sugar beetles, tree racers and ground beetles, various bugs, butterflies, etc. are plentiful. All of them, however, either they hide under the bark, in cracks, etc., or live high in the crowns, and it is not easy to notice them right away. In general, it can be said that, at the family level, the previously described groups of invertebrate evergreen equatorial forests of Africa and America are very similar to those of Asian guiles. Even greater similarity in the set of biological groups of these animals, as well as in their ratio; biomass is dominated by consumers of dying primary production (termites, etc.) and phytophages. Among predators and animals with mixed nutrition, ants predominate, among pollinators - various bees (trigons, arboreal xylocop bees).
Of the amphibians, various toads and frogs are abundantly represented. Tree frogs almost do not enter the limits of gils and moist monsoon forests, although they live both in East Asia and in Australia and New Guinea. On the other hand, it is precisely in those regions of tropical Asia where there are no or few tree frogs that the species of the copepod frog families that replace them are abundantly represented. Some species of the latter genus have the ability to glide with the help of wide webs between the toes of the front and hind legs. The length of flights from tree to tree can reach 12 m. Many crayfish lay their eggs in foamy lumps on leaves or carry them for some time. Hatched tadpoles after some time fall into the water and complete their development there. Both on trees and on the surface of the earth, various species of narrow-mouthed live, feeding mainly on termites and ants. Of these, we mention the decorated frog, which has an amazingly loud voice. During mating calls, the male's whole body swells and resonates.
The various reptiles of the evergreen forests are also almost exclusively zoophagous. As on other continents, one of the most abundant reptiles are geckos, most of which live in the crowns and on tree trunks. Among the agama lizards, the types of flying dragons are exceptionally peculiar. Due to the wide leathery folds on the sides of the body, they are capable of gliding flight at a distance of up to 30 m. Of the other species of this family, we will mention very numerous calots.
In the ground layer, and partially in the soil layer, skinks live. There are no amphisbaenas so characteristic of Africa and America in Asia, but typhlopid blind snakes are just as typical. The arboreal forms of snakes in the Asian hyla are no less diverse. Let us mention bronze snakes and dendrilafis from already-shaped ones. Related decorated snakes are interesting for their ability to plan jumps from tree to tree. At the same time, the animal greatly flattens the body, pushing the ribs apart. In various types of forests of South and Southeast Asia, whip snakes live, the whole life of which also passes on trees.
I. Natural zone of savannas and light forests. In the subequatorial belt O cages fall mainly or almost exclusively in summer. Long droughts alternate with devastating floods. Total radiation 160–180 kcal/cm2 year, radiation balance 70–80 kcal/cm2 year. The temperature of the warmest month reaches 30–34°, the coldest month is mostly above 15–20° (up to 24–25°). The highest temperatures are observed at the end of the dry season, before the onset of rains (more often in May). These climate features give a certain commonality to all landscapes located between tropical deserts and humid equatorial hylaea. However, here there is a frequent change of different landscape types, depending on the general degree of moisture and the duration of the dry and wet periods. Suffice it to note that the average annual precipitation within the considered part of the mainland ranges from 200 mm to 3000 mm or more (in the mountains - up to 12000 mm), and the humidity coefficient is from 0.1 to 3 and more. Accordingly, several main types of landscapes can be distinguished: tropical desert savannahs, subequatorial savannahs, semi-arid woodlands (dry monsoon forests) and semi-humid monsoon forests. In Asia, we observe a complex picture of peninsulas and archipelagos with powerful mountain barriers that sharpen the contrast of moisture, with barrier-rain and barrier-shadow effects in relation to wet monsoon flows. Here, there is a tendency to change different types of landscapes in longitude, but against this general background, there is a "striped pattern" due to orography.
A.Arid landscapes of tropical desert savannas adjoining tropical deserts from the east, they serve as a transition from deserts to subequatorial savannahs. They occupy the northwest of Hindustan, as well as a strip in the west of the peninsula in the barrier shadow of the Western Ghats. In addition, the central part of the intermountain plain in the Irrawaddy basin should be attributed to this type. The annual rainfall is 200–600 mm. The dry season lasts 8–10 months. Zonal soils are reddish brown savannah . Significant areas are occupied by alluvial, predominantly cultivated, soils. Natural vegetation, where due to plowing, and where due to overgrazing, has almost not been preserved. It is characterized by hard grasses, thorny bushes and rare deciduous hard-leaved trees - acacias, prozopis, tamarix, jujube, etc. By the nature of the animal population, these landscapes are also close to desert ones.
B.Subequatorial monsoon forest-savannah (semiarid) landscapes. In the central part of Hindustan, deserted savannas turn into landscapes of typical savannahs. The annual precipitation here is 800–1200 mm, but evaporation exceeds 2000 mm. The number of dry months is 6–8, and wet months are only 2–4. On the eastern outskirts of Hindustan, up to 1200–1600 mm of precipitation falls annually. Although treeless landscapes predominate in the center of Hindustan, and landscapes with dry deciduous monsoon forests prevail on its eastern outskirts, it is advisable to consider them together, since they often alternate. Forests are usually confined to elevations . In addition to Hindustan, such landscapes are common in the interior of Indochina, in the southwest of the Philippine Islands, in the eastern part of the island of Java and in the Lesser Sunda Islands (in the southern hemisphere, the wet period occurs mainly in December - April).
Red-brown soils of the savannas formed on the weathering crust. Often with ferruginous-manganese nodules, low in humus, poor in bases, phosphorus, and nitrogen. Under the variable-moist forests are formed red ferritic (ferruginous) soils with a thick but weakly differentiated profile, with ferruginous concretions, sometimes with dense lateritic layers. There is also little humus in them. On volcanic rocks (basalts) are widespread black tropical (montmorillonite) soils, or regura , up to 1 m thick, clayey. These soils are characterized by high moisture capacity and swell strongly during rains. common alluvial soils, solonchaks are found.
Vegetation cover is severely disturbed. V savanna landscapes proper dominated by a cover of tall (1-3 m) hard grasses - emperors, temedy, wild sugar cane and other species or shrubs and ferns. Often there are bamboo groves, single teak trees, palmyra palms. Variable-moist deciduous forests characteristic of elevated regions (especially mountains) and richer soils. In these forests, species with valuable wood predominate - teak and sal . In teak forests, the entire tree layer and 90% of the undergrowth are deciduous. Lard has a very short leafless period. Under typical conditions, teak forms the upper tier (35–45 m). In the middle tier, red and white sandalwood, satin tree, arborvitae, iron tree, several types of palm trees grow; in the lower - terminalia, mimosa, bamboo.
Teak forests are intensively cut down. On the plains, they are almost completely reduced and, as a result of repeated burning, they are replaced by shrubs and grass communities, which are difficult to distinguish from natural savannahs. Teak can regenerate under the shade of bamboo. The Deccan Plateau is characterized by multi-stemmed banyans , whose crowns reach 200–500 m in circumference.
Animal world diverse: some monkeys (including gibbon), three species of bear, panda, several species of deer, buffalo, wild bull, elephant, rhinoceros, tiger, leopard, peacocks, banker chickens, pheasants, hornbills, weavers, nectaries, etc.
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