Natural zone: humid equatorial forests or tropical rainforest, features, climate, soils, geographical location. rainforest plants rainforest flora and fauna

Structure and structure. It is almost impossible to give a generalized description of the structure of the tropical rain forest: this most complex plant community exhibits such a variety of types that even the most detailed descriptions. A few decades ago, it was believed that a wet forest is always an impenetrable thicket of trees, shrubs, ground grasses, lianas and epiphytes, since it was mainly judged by descriptions of mountain rainforests. Only relatively recently it became known that in some humid tropical forests, due to the dense closure of the crowns of tall trees, sunlight almost does not reach the soil, so the undergrowth here is sparse, and one can pass through such forests almost unhindered.

It is customary to emphasize the species diversity of the tropical rainforest. It is often noted that it is unlikely to find two specimens of trees of the same species in it. This is a clear exaggeration, but at the same time, it is not uncommon to find 50-100 species of trees on an area of ​​1 hectare.

But there are also relatively species-poor, "monotonous" moist forests. These include, for example, special forests, consisting mainly of trees of the dipterocarpaceae family, growing in areas of Indonesia that are very rich in precipitation. Their existence indicates that in these areas the stage of optimal development of wet rainforest already passed. The extreme abundance of precipitation makes it difficult to aerate the soil, as a result, there was a selection of plants that have adapted to living in such places. Similar conditions of existence can also be found in some damp regions of South America and the Congo basin.

The dominant component of the tropical rainforest is trees of different appearance and different heights; they make up about 70% of all species found here higher plants. There are three tiers of trees - upper, middle and lower, which, however, are rarely clearly expressed. The upper tier is represented by individual giant trees; their height, as a rule, reaches 50-60 m, and the crowns develop above the crowns of trees located below the tiers. The crowns of such trees do not close, in many cases these trees are scattered in the form of individual specimens that seem to be overgrown. On the contrary, the crowns of trees of the middle tier, having a height of 20-30 m, usually form a closed canopy. Due to the mutual influence of neighboring trees, their crowns are not as wide as those of the trees of the upper tier. The degree of development of the lower tree layer depends on the illumination. It is made up of trees reaching an average of about 10 meters in height. A special section of the book will be devoted to lianas and epiphytes found in different tiers of the forest (pp. 100-101).

Often there is also a tier of shrubs and one or two tiers of herbaceous plants, they are representatives of species that can develop under minimal illumination. Since the humidity of the surrounding air is constantly high, the stomata of these plants remain open throughout the day and the plants are not in danger of wilting. Thus, they constantly assimilate.

According to the intensity and nature of growth, the trees of the tropical rainforest can be divided into three groups. The first are species whose representatives grow rapidly, but do not live long; they are the first to develop where light areas are formed in the forest, either naturally or as a result of human activity. These light-loving plants stop growing after about 20 years and give way to other species. Such plants include, for example, the South American balsa tree ( Ochroma lagopus) and numerous myrmecophilous species of cecropia ( Cecropia), an African species Musanga cecropioides and representatives of the Euphorbiaceae family growing in tropical Asia, belonging to the genus Macaranga.

The second group includes species whose representatives on early stages development also grow rapidly, but their growth in height lasts longer, and at the end of it they are able to live for a very long time, probably more than one century. These are the most characteristic trees of the upper tier, the crowns of which are usually not shaded. These include many economically important trees, the wood of which is commonly called "mahogany", for example, species belonging to the genera Swietenia(tropical America), Khaya And Entandrophragma(tropical Africa).

Finally, the third group includes representatives of shade-tolerant species that grow slowly and are long-lived. Their wood is usually very heavy and hard, it is difficult to process it, and therefore it does not find such a wide application as the wood of trees of the second group. Nevertheless, the third group includes species that give noble wood, in particular Tieghemella heckelii or Aucomea klainiana, the wood of which is used as a substitute for mahogany.

Most of the trees are characterized by straight, columnar trunks, which often, without branching, rise to more than 30 meters in height. Only there, a spreading crown develops in isolated giant trees, while in the lower tiers, as already mentioned, the trees, due to their close arrangement, form only narrow crowns.

In some species of trees near the bases of the trunks, board-shaped roots form (see figure), sometimes reaching a height of up to 8 m. They give the trees greater stability, since the root systems that develop shallowly do not provide a strong enough fixation for these huge plants. The formation of plank roots is genetically determined. Representatives of some families, such as Moraceae (mulberry), Mimosaceae (mimosa), Sterculiaceae, Bombacaceae, Meliaceae, Bignoniaceae, Combretaceae, have them quite often, while others, such as Sapindaceae, Apocynaceae, Sapotaceae, do not have them at all.

Trees with plank roots most often grow in damp soils. It is possible that the development of plank roots is associated with poor aeration characteristic of such soils, which prevents the secondary growth of wood on inner sides lateral roots (it is formed only from their outer sides). In any case, trees growing on permeable and well-aerated soils of mountain rainforests do not have plank roots.

Trees of other species are characterized by stilted roots; they are formed above the base of the trunk as adnexal and are especially common in trees of the lower tier, also growing mainly in damp habitats.

Differences in the microclimate characteristic of different tiers of the tropical rainforest are also reflected in the structure of the leaves. While upper-story trees typically have elliptical or lanceolate, smooth and dense leathery laurel-like leaves (see figure on page 112) that can tolerate alternating dry and wet periods throughout the day, the leaves of lower-story trees exhibit signs indicating intensive transpiration and rapid removal of moisture from their surface. They are usually larger; their plates have special points on which water collects and then drops from them, so there is no water film on the leaf surface that would prevent transpiration.

The change of foliage in trees of humid tropical forests is not affected by external factors, in particular drought or cold, although here, too, a certain periodicity, which varies in different species, can be replaced. In addition, some independence of individual shoots or branches is manifested, so not the whole tree is leafless at once, but only part of it.

Features of the climate of the humid tropical forest also affect the development of foliage. Since there is no need to protect growing points from cold or drought, as in areas with temperate climate, the kidneys are relatively weakly expressed and are not surrounded by renal scales. With the development of new shoots, many trees of the tropical rainforest experience "drooping" of the leaves, which is caused exclusively by the rapid increase in their surface. Due to the fact that mechanical tissues do not form as quickly, young petioles at first, as if withered, hang down, the foliage seems to droop. The formation of the green pigment - chlorophyll - can also be slowed down, and young leaves turn whitish or - due to the content of the anthocyanin pigment - reddish (see figure above).


"drooping" of the young leaves of the chocolate tree (Theobroma cacao)

The next feature of some tropical rain forest trees is caulifloria, that is, the formation of flowers on the trunks and leafless parts of the branches. Since this phenomenon is observed primarily in trees of the lower tier of the forest, scientists interpret it as an adaptation to pollination, which is often found in these habitats, with the help of bats(chiropterophilia): pollinating animals - bats and flying dogs - when approaching a tree, it is more convenient to grab onto the flowers.

Birds also play a significant role in the transfer of pollen from flower to flower (this phenomenon is called "ornithophilia"). Ornithophilous plants are conspicuous by the bright colors of their flowers (red, orange, yellow), while chiropterophilous plants usually have inconspicuous, greenish or brownish flowers.

A clear distinction between the tiers of shrubs and grasses, as, for example, is typical for the forests of our latitudes, practically does not exist in tropical rainforests. One can only note the upper tier, which, along with tall large-leaved representatives of the banana, arrowroot, ginger and aroid families, includes shrubs and young undergrowth of trees, as well as the lower tier, represented by undersized, extremely shade-tolerant herbs. In terms of the number of species, herbaceous plants in the tropical rainforest are inferior to trees; but there are also such lowland moist forests that have not experienced human influence, in which only one tier of grasses poor in species is generally developed.

Attention is drawn to the fact of variegation, which has not yet found an explanation, as well as the presence of metallic-shiny or matte-velvety surface areas on the leaves of plants living in the subsoil layer of grasses of a humid tropical forest. Obviously, these phenomena are to some extent connected with the optimal use of that minimum sunlight that reaches such habitats. Many "variegated" plants of the lower tier of rainforest grasses have become favorite indoor ornamental plants, such as species of the genera Zebrina, Tradescantia, Setcreasea, Maranta, Calathea, Coleus, Fittonia, Sanchezia, Begonia, Pilea and others (figure on page 101). The deep shade is dominated by various ferns, mosquitoes ( Selaginella) and mosses; the number of their species is especially great here. So, most species of mosquitoes (and there are about 700 of them) are found in tropical rainforests.

Also noteworthy are saprophytic (that is, using decaying organic matter) fungi of the Clathraceae and Phallaceae families living on the soil of tropical rainforests. They have peculiar fruit bodies- "mushroom-flowers" (see picture on page 102).

Lianas. If you swim through the tropical rain forest along the river, the abundance of lianas (plants with woody stems climbing trees) is striking - they, like a dense curtain, cover the trees growing along the banks. Lianas are one of the most amazing components of the vegetation cover of tropical regions: over 90% of all their species are found only in the tropics. Most grow in moist forests, although they require good lighting to thrive. That is why they do not occur everywhere with the same frequency. First of all, they can be seen along the forest edges, in naturally formed light areas of the forest and - at least sometimes - in permeable to sun rays layers of woody plants (see illustration on page 106). They are especially abundant on plantations established in areas of tropical rainforests, and in secondary forests that appear in clearings. In the lowland moist forests, which have not experienced the influence of man, where the dense, well-developed crowns of trees are tightly closed, creepers are relatively rare.

According to the method of fixing on the plants that serve as their support, creepers can be divided into different groups. For example, leaning creepers can be held on other plants with the help of supporting (clinging) shoots or leaves, thorns, thorns, or special outgrowths such as hooks. Typical examples of such plants are rattan palms of the genus Calamus, 340 species of which are distributed in the tropics of Asia and America (see the figure on page 103).

Rooted creepers are held on a support with the help of many small adventitious roots or cover it with longer and thicker roots. These are many shade-tolerant vines from the aroid family, for example, species of the genera Philodendron, Monstera, Raphidophora, Syngonium, Pothos, Scindapsus, as well as vanilla ( vanilla) is a genus from the orchid family.

Curly vines cover the support with internodes that grow strongly in length. Usually, as a result of subsequent thickening and lignification, such shoots are fixed tightly. Most tropical vines belong to the climbing group, for example, representatives of the mimosa family and the related Caesalpinia family, rich in species and common throughout the tropics, in particular climbing entada ( Entada scandens); the beans of the latter reach 2 m in length (see drawing on page 104). To the same group belong the so-called monkey ladder, or sarsaparilla bauginia ( Bauhinia smilacina), forming thick woody shoots, as well as creepers with bizarre flowers (species of kirkazon, Aristolochia; kirkazon family) (see figure on page 103).

Finally, the vines attached with tendrils form lignified tendrils - with which they cling to the plants that serve as their support. These include representatives of the genus distributed throughout the tropics. Cissus from the Vinogradov family, different types of legumes, in particular (see figure), as well as types of passionflower ( Passiflora; family of passionflowers).

Epiphytes. Extremely interesting are the adaptations to the conditions of existence in tropical rainforests in the so-called epiphytes - plants that live on trees. The number of their species is very large. They abundantly cover the trunks and branches of trees, due to which they are quite well lit. Developing high on trees, they lose the ability to get moisture from the soil, so the supply of water becomes a vital factor for them. It is not surprising that there are especially many types of epiphytes where precipitation is plentiful and the air is humid, but for their optimal development, it is not the absolute amount of precipitation that is decisive, but the number of rainy and foggy days. The unequal microclimate of the upper and lower tree layers is also the reason why the communities of epiphytic plants living there are very different in species composition. In the outer parts of the crowns, light-loving epiphytes dominate, while shade-tolerant ones dominate inside, in constantly wet habitats. Light-loving epiphytes are well adapted to the change of dry and wet periods of time that occurs during the day. As the examples below show, they use different possibilities to do this (picture on page 105).

In orchids, represented by a huge number of species (and most of the 20,000-25,000 orchid species are epiphytes), organs that store water and nutrients, serve as thickened areas of shoots (the so-called bulbs), leaf blades or roots. This lifestyle is also facilitated by the formation of aerial roots, which are covered on the outside with layers of cells that quickly absorb water (velamen).

Tropical rainforest plants growing in the ground layer

The bromeliad or pineapple family (Bromeliaceae), whose representatives are common, with one exception, in Northern and South America, consists almost entirely of epiphytes, whose funnel-like rosettes of leaves serve as water-collecting reservoirs; of these, water and nutrients dissolved in it can be absorbed by scales located at the base of the leaves. Roots serve only as organs that attach plants.

Even cacti (for example, species of genera Epiphyllum, Rhipsalis, Hylocereus And Deamia) grow as epiphytes in mountain rainforests. With the exception of a few species of the genus Rhipsalis, also found in Africa, Madagascar and Sri Lanka, they all grow only in America.

Some ferns, such as the bird's nest fern, or nesting asplenium ( Aspleniumnidus), and deer-antler fern, or deer-horned platicerium ( Platycerium), due to the fact that the first leaves form a funnel-shaped rosette, and the second has special leaves adjacent to the trunk of the supporting tree, like patch pockets (picture on page 105), they are even able to create a soil-like, constantly moist substrate in which their roots grow.

Epiphytes that develop in shaded habitats are primarily represented by the so-called hygromorphic ferns and mosses, which have adapted to existence in a humid atmosphere. The most characteristic components of such communities of epiphytic plants, which are especially pronounced in mountain moist forests, are hymenophyllous, or thin-leaved, ferns (Hymenophyllaceae), for example, representatives of the genera Hymenophyllum And Trichomanes. As for lichens, they do not play such a big role because of their slow growth. Of the flowering plants in these communities, there are species of the genera Peperomia And Begonia.

Even the leaves, and above all the leaves of the trees of the lower tiers of the humid tropical forest, where the humidity of the air is constantly high, can be inhabited by various lower plants. This phenomenon is called epiphylly. Lichens, hepatic mosses and algae mainly settle on the leaves, forming characteristic communities.

A kind of intermediate step between epiphytes and vines are hemiepiphytes. They either grow first as epiphytes on tree branches, and as aerial roots form, reaching the soil, they become plants that strengthen themselves in the soil, or in the early stages they develop as lianas, but then lose contact with the soil and thus turn into epiphytes. The first group includes the so-called strangler trees; their aerial roots, like a net, cover the trunk of the support tree and, growing, prevent its thickening to such an extent that the tree eventually dies off. And the totality of aerial roots then becomes, as it were, a system of "trunks" of an independent tree, in the early stages of development of the former epiphyte. The most characteristic examples of strangler trees in Asia are species of the genus Ficus(mulberry family), and in America - representatives of the genus Clusia(St. John's wort family). The second group includes species of the aroid family.

Lowland evergreen tropical rainforests. Although the floristic composition of tropical rainforests in different areas the globe is very different, and the three main areas of such forests show only a slight similarity in this respect, yet similar modifications of the main type can be found everywhere in the nature of their vegetation cover.

The prototype of the tropical rainforest is considered to be an evergreen tropical rainforest of unflooded lowlands that are not damp for a long time. This is, so to speak, a normal type of forest, the structure and features of which we have already spoken about. Forest communities of river floodplains and flooded lowlands, as well as swamps, differ from it in usually less rich species composition and the presence of plants that have adapted to existence in such habitats.

Floodplain rainforests found in close proximity to rivers in regularly flooded areas. They develop in habitats formed as a result of the annual deposition of nutrient-rich river sediment - tiny particles brought by the river suspended in water and then settled. This muddy water the so-called "white water" rivers bring mainly from the treeless regions of their basins *. The optimal content of nutrients in the soil and the relative supply of running water with oxygen determine the high productivity of plant communities developing in such habitats. Floodplain rainforests are difficult to access for human development, so they have largely retained their originality to this day.

* (Rivers, called "white water" by the authors of this book, in Brazil are usually called white (rios blancos), and "black water" - black (rios negros). White rivers carry muddy water rich in suspended particles, but the color of the water in them can be not only white, but also gray, yellow, etc. In general, the rivers of the Amazon basin are characterized by an amazing variety of water colors. Black rivers are usually deep; the waters in them are transparent - they seem dark only because there are no suspended particles in them that reflect light. Humic substances dissolved in water only enhance this effect and, apparently, affect the color shade.)

Tropical rainforest vines

Moving from the very bank of the river across the floodplain to its edge, one can identify a characteristic succession of plant communities due to the gradual lowering of the soil surface level from high riverbeds to the edge of the floodplain. Riverside forests rich in lianas grow on seldom flooded riverbanks, further from the river turning into a real flooded forest. At the farthest edge of the floodplain, there are lakes surrounded by reed or grass marshes.

Swampy rain forest. In habitats whose soils are almost constantly covered with stagnant or slowly flowing water, marshy tropical rain forests. They can be found mainly near the so-called "black-water" rivers, the sources of which are located in forested areas. Therefore, their waters do not carry suspended particles and have a color from olive to black-brown due to the content of humic substances in them. The most famous "black-water" river is the Rio Negro, one of the most important tributaries of the Amazon; it collects water from a vast area with podzolic soils.

In contrast to the floodplain rainforest, swampy forest usually covers the entire river valley. Here there is no deposition of pumps, but, on the contrary, only uniform washing out, therefore the surface of the valley of such a river is even.

Due to the insecurity of habitats, marshy rain forests are not as lush as floodplain forests, and due to the lack of air in the soil, plants with aerial and stilted roots are often found here. For the same reason, the decomposition of organic matter occurs slowly, which contributes to the formation of thick peat-like layers, most often consisting of more or less decomposed wood.

Semi-evergreen lowland moist forests. Some areas of tropical rain forests experience short dry spells that cause leaf changes in the upper forest layer trees. At the same time, the lower tree tiers remain evergreen. Such a transitional stage to dry forests leafy during the rainy season (see p. 120) has been called "semi-evergreen or semi-deciduous lowland moist forests". During dry periods, there can be movement of moisture in the soil from the bottom up, so these forests receive enough nutrients and are very productive.

Epiphytes of the tropical rainforest


Above Asplenium nest Asplenium nidus and below Cattleya citrina

Montane tropical rainforests. The forests described above, whose existence is determined by the presence of water, can be contrasted with those variants of the tropical rainforest, the formation of which is associated with a decrease in temperature; they are mainly found in moist habitats located in different altitudinal zones mountainous areas tropical regions. In the foothill zone, at an altitude of about 400-1000 m above sea level, the tropical rainforest almost does not differ from the lowland forest. It has only two tiers of trees, and the top tier trees are not as tall.

On the other hand, the tropical rain forest of the mountain belt, or, as they say, the mountain rain forest, growing at an altitude of 1000-2500 m, reveals more significant differences. It also has two tree layers, but they are often difficult to identify, and their upper limit often does not exceed 20 m. In addition, there are fewer tree species here than in lowland moist forests, and some characteristics trees of such forests, in particular stilted roots, as well as caulifloria. Tree leaves are usually smaller and do not have points to remove water droplets.

The shrub and grass layers are often dominated by ferns and bamboo species. Epiphytes are very abundant, while large creepers are rare.

For more high altitudes In the constantly humid tropics (2500-4000 m), mountain rain forests are replaced by subalpine mountain forests that develop at cloud level (see t. 2).

Tropical forests are forests that grow in tropical and subtropical regions. Tropical forests cover about six percent of the Earth's land surface. There are two main types of rainforest: tropical rainforests (such as those in the Amazon or the Congo Basin) and dry rainforests (such as those in southern Mexico, the plains of Bolivia, and the western regions of Madagascar).

Rainforests typically have four distinct layers that define the structure of the forest. The tiers include forest floor, undergrowth, top canopy (forest canopy) and top tier. Forest floor, the darkest place in the rainforest, where little sunlight penetrates. The undergrowth is the layer of forest between the ground and up to a height of about 20 meters. It includes shrubs, herbs, small trees and trunks. large trees. Forest canopy - is a canopy of tree crowns at a height of 20 to 40 meters. This tier is made up of tall tree tops that are home to a variety of rainforest animals. Most of the food resources in the rainforest are in the upper canopy. The upper tier of the rainforest includes the crowns of the tallest trees. This tier is located at an altitude of about 40-70 meters.

The main characteristics of the rainforest

The following are the main characteristics of tropical forests:

  • tropical forests are located in the tropical and subtropical regions of the planet;
  • rich in species diversity of flora and fauna;
  • drops out here a large number of precipitation;
  • rainforests are threatened with extinction due to clearing for timber, farming and grazing;
  • The rainforest structure consists of four layers (forest floor, undergrowth, canopy, topstory).

Tropical forest classification

  • Tropical rainforests, or tropical rainforests, are forest habitats that receive abundant rainfall throughout the year (usually over 200 cm per year). wet forests located close to the equator and receive sufficient sunlight to maintain average annual temperature enough air high level(between 20° and 35° C). Tropical rainforests are among the most species-rich habitats on earth. They grow in three main areas around the world: Central and South America, West and Central Africa, and Southeast Asia. Of all tropical rainforest regions, South America is the largest in the world: it covers about 6 million square kilometers.
  • Tropical dry forests are forests that receive less rainfall than tropical rainforests. Dry forests usually have a dry season and a rainy season. Although rainfall is sufficient to support vegetation growth, trees must be able to withstand long periods of drought. Many tree species that grow in tropical dry forests are deciduous and shed their leaves during the dry season. This allows the trees to reduce their water needs during the dry season.

rainforest animals

Examples of several animals that inhabit rainforests:

  • (Panthera onca) is a large feline that lives in the tropical forests of Central and South America. The jaguar is the only panther species found in the new world.
  • Capybara, or capybara (Hydrochoerus hydrochaeris) is a semi-aquatic mammal that inhabits the forests and savannas of South America. Capybaras are the largest rodents living today.
  • Howler monkeys (Aloautta) - a genus of monkeys, which includes fifteen species inhabiting tropical forests throughout Central and South America.

You can find out more information about the animals of the Amazon rainforest in the article "".

The most useful plants of the rainforest, exotic fruits, medicinal plants. Encyclopedia of the 54 most interesting views plants that can be useful to humans in a tropical rainforest. ATTENTION! I recommend that all unfamiliar plants be considered poisonous by default! Even the ones you're just not sure about. Tropical rainforests are the most diverse ecosystem on our planet, and therefore here I have collected only those plants that can somehow be useful to humans.

1) Coconut tree

Plant sea ​​coasts preferring sandy soils. In a lot of useful substances: vitamins A, C and group B; minerals: calcium, sodium, potassium, phosphorus, iron; natural sugars, proteins, carbohydrates, fatty oil, organic acids. Coconut milk is often used as an alternative to physical. solution for the high content of various salts and trace elements in it. Coconut milk will help you regulate the body's salt balance.

  • Coconut palm has a reputation as a strong aphrodisiac and normalizes the reproductive system. Milk and pulp of coconut well restores strength and improves eyesight;
  • Improve work digestive system and liver;
  • Normalize the function of the thyroid gland;
  • Relax muscles and help with joint problems;
  • Increase immunity and resistance to various infections, reduce the adaptability of bacteria to antibiotics;
  • Pulp and coconut oil, thanks to their lauric acid (this is the main fatty acid found in breast milk), normalize blood cholesterol levels;
  • Help the body with flu and colds, AIDS, diarrhea, lichen and gallbladder disease
  • They have anthelmintic, antimicrobial, antiviral wound-healing effects;
  • Reduce the risk of atherosclerosis and other diseases of the cardiovascular system, as well as cancer and degeneration processes.

ATTENTION! Dropping a coconut on your head can be fatal! This is the cause of death for many people!

2) Banana

If you want to quickly restore your body's low energy level, there is no better snack than a banana. Studies have proven that just two bananas provide enough energy for 1.5 hours of vigorous work. Good food product, due to the content of a large amount of carbohydrates, it can be eaten instead of the potatoes we are used to. Helps with many diseases such as anemia, ulcers, lowers blood pressure, Improves mental capacity Helps with constipation, depression, heartburn. The peel helps to get rid of warts. One banana contains an average of 60-80 calories. The composition of the banana includes such chemical elements as iron, potassium, sodium, magnesium, phosphorus and calcium. Eating 2 bananas during the day, you will fill the body's need for potassium and two-thirds - for magnesium. In addition, the banana contains vitamins A, B1, B2, B3, B6, B9, E, PP. The substance ephedrine contained in bananas, when used systematically, improves the activity of the central nervous system, and this directly affects overall performance, attention and mood.

3) Papaya

Papaya leaves, depending on their age, processing method and, in fact, the recipe itself, are used to reduce high blood pressure, treatment of kidney infection, stomach pain and bowel problems. Papaya fruits are used in the treatment of fungal diseases and ringworm. The papaya fruit and leaves also contain the alkaloid carpaine, an anthelmintic alkaloid that can be dangerous in large doses. Papaya fruits are not only appearance, but also by chemical composition very close to melon. They contain glucose and fructose, organic acids, proteins, fiber, beta-carotene, vitamins C, B1, B2, B5 and D. Minerals are represented by potassium, calcium, phosphorus, sodium, and iron.

4) Mango

Mangoes normalize bowel function, two green mangoes a day will save you from diarrhea, constipation, hemorrhoids, as well as prevent bile stasis and disinfect the liver. When eating green fruits (1-2 per day), the elasticity of blood vessels improves, due to the high content of iron in fruits, mango is useful for anemia. And the high content of vitamin C makes it an excellent remedy for beriberi. When using more than two unripe fruits per day, colic, irritation of the mucosa of the gastrointestinal tract and throat may occur. Overeating ripe fruits can lead to intestinal upset, constipation, and allergic reactions. Mango contains a large amount of vitamin C, B vitamins, as well as vitamins A, E, contains folic acid. Mango is also rich in minerals such as potassium, magnesium, zinc. Regular consumption of mango strengthens the immune system. Due to the content of vitamins C, E, as well as carotene and fiber, the use of mango helps prevent cancer of the colon and rectum, is the prevention of cancer and other organs. Mango is an excellent antidepressant, improves mood, relieves nervous tension.

The flora of the tropical forests is extremely diverse. Among the trees that grow on the coasts, you can find a coconut palm. Their fruits - coconuts are very useful, used in cooking and cosmetology.

Here you can find different types of banana plants that people use as fruits and vegetables, depending on the stage of ripening.

banana plant

One of tropical plants is a mango, among which the most famous type of Indian mango.

The melon tree, better known as papaya, grows in forests and is of great economic importance.

melon tree, papaya

Breadfruit is another representative of the forests, where nutritious fruits are highly valued.

One of the family mulberry trees is marang.

In tropical rainforests, the durian plant can be found. Their flowers grow directly on the trunks, and the fruits are protected by thorns.

In South Asia, the citrus-leaved morinda grows, has edible fruits that are part of the diet of the population of some Pacific islands.

Pitaya is a vine-like rainforest cactus that has sweet and edible fruits.

One of the interesting tropical plants is the rambutan tree. It reaches a height of 25 meters and is evergreen.

Rambutan

Small evergreen trees of the guava species grow in tropical forests.

The fast growing evergreen tropical tree Perseus americana is nothing but the avocado plant found in many forests.

perseus americana, avocado

Various types of ferns, mosses and lichens, creepers and epiphytes, bamboos, sugarcane, cereals grow in tropical forests.

Rainforest levels

Typically, a tropical forest has 4-5 tiers. At the very top, trees grow up to 70 meters. These are evergreen trees. In seasonal forests, they shed their leaves during the drought period. These trees protect the lower levels from wind, rain and cold. Then the crown layer (canopy) begins at the level of 30-40 meters. Here the leaves and branches are very close to each other. It is very difficult for people to reach this height in order to explore the world of flora and fauna of the canopy. They use special techniques and aircraft. Average level forests are undergrowth. A kind of living world has formed here. Then comes the padding. These are various herbal plants.

The flora of tropical forests is very diverse. Scientists have not studied these forests yet, because they are very difficult to pass. In the future, new plant species will be discovered in tropical forests.

About half of all forests on our planet are tropical forests (hylaea) that grow in Africa, Southeast Asia, South and Central America. Tropical forests are located between 25° northern latitude and 30° south latitude, where heavy rains are frequent. The rainforest ecosystem covers less than two percent of the Earth's surface, but 50 to 70 percent of all life forms on our planet are found here.

The largest rainforests are found in Brazil (South America), Zaire (Africa) and Indonesia (Southeast Asia). Also, the rainforest is found in Hawaii, the islands Pacific Ocean and the Caribbean.

Rainforest climate

The climate in the rainforest is very warm, characterized and humid. From 400 to 1000 cm of precipitation falls here annually. The tropics are characterized by a uniform annual distribution of precipitation. The change of seasons is almost non-existent, and average temperature air is 28 degrees Celsius. All these conditions have significantly influenced the formation of the richest ecosystem on our planet.

Soil in the rainforest

The soil of the tropics is poor in minerals and nutrients - there is a lack of potassium, nitrogen and other trace elements. Usually it has a red and red-yellow color. Due to frequent precipitation, nutrients are absorbed by the roots of plants or go deep into the soil. That is why the natives of the rainforests used a slash-and-burn agricultural system: in small areas, all vegetation was cut down, it was subsequently burned, then the soil was cultivated. The ash acts as a nutrient. When the soil begins to turn infertile, usually after 3-5 years, the inhabitants of tropical settlements moved to new areas for farming. Agriculture. It is a sustainable farming method that ensures that the forest is constantly regenerated.

rainforest plants

Warm humid climate The rainforest provides the perfect environment for a vast abundance of amazing plant life. The rainforest is divided into several tiers, which are characterized by their own flora and fauna. Most tall trees tropics, receive the largest number sunlight, as they reach a height of over 50 meters. Here, for example, include the cotton tree.

The second tier is the dome. It is home to half of the rainforest's wildlife - birds, snakes and monkeys. This includes trees with a height of less than 50 m with wide leaves, hiding sunlight from the lower floors. These are philodendron, poisonous strychnos and rattan palms. Lianas usually stretch along them towards the sun.

The third tier is inhabited by shrubs, ferns and other shade-tolerant species.

The last tier, the lower one, is usually dark and damp, since the sun's rays hardly penetrate here. It consists of overripe foliage, fungi and lichens, as well as young shoots of plants of higher tiers.

In each of the regions where tropical forests grow, there are different types of trees.

Tropical trees of Central and South America:
  • Mahogany (Sweitinia spp.)
  • Spanish cedar (Cedrella spp.)
  • Rosewood and Cocobolo (Dalbergia retusa)
  • Purple tree (Peltogyne purpurea)
  • Kingwood
  • Cedro Espina (Pochote spinosa)
  • Tulipwood
  • Gaiacan (Tabebuia chrysantha)
  • Pink tabebuya (Tabebuia rosea)
  • Bokote
  • Jatoba (Hymenaea courbaril)
  • Guapinol (Prioria copaifera)
Tropical trees of Africa:
  • Bubinga
  • Ebony
  • Zebrano
  • Pink tree
Tropical trees of Asia:
  • Malaysian maple

In the rainforest, they are widespread, which feed on caught insects and small animals. Among them, it should be noted nepentes (Pitcher Plants), sundew, oilwort, pemphigus. By the way, plants of the lower level, with their bright flowering, attract insects for pollination, since there is practically no wind in these layers.

Valuable crops are grown in the places of clearing of tropical forests:

  • mango;
  • bananas;
  • papaya;
  • coffee;
  • cocoa;
  • vanilla;
  • sesame;
  • sugar cane;
  • avocado;
  • cardamom;
  • cinnamon;
  • turmeric;
  • nutmeg.

These cultures play important role in cooking and cosmetology. Some tropical plants serve as raw materials for drugs, in particular, anti-cancer drugs.

Adaptation of tropical plants for survival

Any flora needs moisture. There is no lack of water in the rainforest, but often there is too much of it. Rainforest plants must survive in areas where there is constant rainfall and flooding. The leaves of tropical plants help to beat off raindrops, and some species are armed with a drip tip designed to quickly drain rain.

Plants in the tropics need light to live. The dense vegetation of the upper tiers of the forest transmits little sunlight to the lower tiers. Therefore, rainforest plants must either adapt to life in constant twilight or grow rapidly upwards in order to "see" the sun.

It is worth noting that in the tropics trees grow with thin and smooth bark, which is able to accumulate moisture. Some types of plants in the lower part of the crown have leaves wider than at the top. This helps to pass more sunlight to the soil.

As for the epiphytes themselves, or air plants that grow in the rainforest, they get their nutrients from plant debris and bird droppings that land on their roots and do not depend on poor soil forests. In tropical forests, there are such air plants as orchids, bromeliads, ferns, large-flowered selenicereus and others.

As mentioned, the soil in most rainforests is very poor and lacks nutrients. To capture nutrients at the top of the soil, most rainforest trees have shallow roots. Others are wide and powerful, as they must hold a massive tree.

rainforest animals

Animals of the rainforest amaze the eye with their diversity. It is in this natural area that you can meet the largest number of representatives of the fauna of our planet. Most of them are in the Amazon rainforest. For example, there are 1800 species of butterflies alone.

In general, the tropical forest is the habitat of most amphibians (lizards, snakes, crocodiles, salamanders), predators (jaguars, tigers, leopards, cougars). All animals of the tropics are brightly colored, as the spots and stripes are the best camouflage in the dense thicket of the jungle. The sounds of the rainforest are provided by the polyphony of songbirds. In the forests of the tropics, the world's largest population of parrots, among others interesting birds there are South American harpies belonging to one of the fifty species of eagles and on the verge of extinction. No less bright birds are peacocks, the beauty of which has long been legendary.

More monkeys also live in the tropics: arachnids, orangutans, chimpanzees, monkeys, baboons, gibbons, red-bearded jumpers, gorillas. In addition, there are sloths, lemurs, Malay and sun bears, rhinos, hippos, tarantulas, ants, piranhas and other animals.

Tropical forest loss

Tropical timber has long been synonymous with exploitation and plunder. giant trees are the goal of entrepreneurs who use them for commercial purposes. How are forests exploited? The most obvious use of rainforest trees is in the furniture industry.

According to the European Commission, about one-fifth of EU wood imports come from illegal sources. Every day, thousands of products from the international wood mafia pass through store shelves. Tropical wood products are often labeled as "luxury wood", "hardwood", "natural wood" and "solid wood". Usually these terms are used to disguise tropical wood from Asia, Africa and Latin America.

The main tropical tree exporting countries are Cameroon, Brazil, Indonesia and Cambodia. most popular and expensive breeds The tropical woods that are on sale are mahogany, teak and rosewood.

To inexpensive breeds tropical tree include meranti, ramin, gabun.

The consequences of deforestation in the rainforest

In most tropical rainforest countries, illegal logging is common and a serious problem. Economic losses reach billions of dollars, and environmental and social damage is incalculable.

Deforestation results in deforestation and profound ecological changes. Tropical forests contain the largest in the world. As a result of poaching, millions of species of animals and plants are losing their habitat and, as a result, disappear.

According to the Red List of the International Union for Conservation of Nature (IUCN), over 41,000 species of plants and animals are threatened, including big monkeys such as gorillas and orangutans. Scientific estimates of lost species vary widely, ranging from 50 to 500 species per day.

In addition, logging equipment used for timber removal destroys sensitive upper layer soil, damages the roots and bark of other trees.

Mining iron ore, bauxite, gold, oil and other minerals also destroy large areas of tropical forests, for example, in the Amazon.

Importance of the rainforest

Tropical rainforests play an important role in the ecosystem of our planet. The cutting of this natural area leads to the formation of the greenhouse effect and, subsequently, to global warming. The largest tropical forest in the world, the Amazon forest, plays the most important role in this process. 20 percent of global greenhouse gas emissions are attributed to deforestation. The Amazon rainforest alone stores 120 billion tons of carbon.

Tropical forests also contain vast amounts of water. Therefore, another consequence of deforestation is a disturbed water cycle. This in turn could lead to regional droughts and changes in global weather patterns, with potentially devastating consequences.

The rainforest is home to unique flora and fauna.

How to protect tropical forests?

To prevent Negative consequences deforestation, it is necessary to expand forest areas, strengthen control over forests at the state and international levels. It is also important to raise people's awareness of the role forests play on this planet. Ecologists say it is also worth encouraging the reduction, recycling and reuse forest products. Go to alternative sources energy, such as fossil gas, can in turn reduce the need to exploit forests for heating.

Deforestation, including tropical deforestation, can be carried out without harming this ecosystem. In Central and South America and Africa, trees are cut down selectively. Only trees that have reached a certain age and thickness of the trunk are cut down, and the young ones remain untouched. This method causes minimal damage to the forest, because it allows it to recover quickly.

mob_info