Natural zone: variable humid forests of Africa and Australia, characteristics, animals, plants, climate, soils. Plants of the equatorial forest
Remember: 1. What is a natural area? 2. What are the patterns of changing natural zones on the plains? What are they due to? 3. What natural areas do you know?
Patterns of distribution of natural zones in Africa. You already know that within each of the natural zones, similar climate, soils, vegetation and animal world. Since the equator crosses Africa approximately in the middle, it is characterized by a clear alternation of identical natural zones to the north and south of the equator, that is, latitudinal zonality is observed. Moist equatorial forests are replaced by savannahs and woodlands, and those - by tropical deserts and semi-deserts.
By map geographical zones and natural zones of the world (see flyleaf 2 of the textbook), find out in which areas of Africa and for what reasons the latitudinal zonality is violated.
The extreme north and south of the mainland are occupied by subtropical hardwood forests and shrubs.
The location of natural zones on the mainland is determined by climatic conditions that are associated with geographic latitude, altitude, the influence of sea currents, and the redistribution of precipitation depending on the relief. Therefore, the latitudinal zonality is broken in some places and the natural zones are extended along the meridians.
Moist equatorial forests. The zone of humid equatorial forests covers the coast of the Gulf of Guinea to the north of the equator and the basin of the Congo River. It stretches for 1600 km from north to south and 5000 km from west to east. This natural area is original and unique. There are practically no seasons here: both in winter and in summer the air temperature is approximately +24 °C. More than 2000 mm of precipitation falls per year. It rains every day, usually in the afternoon. Water and heat create ideal conditions for the development of all living things, so humid equatorial plants grow here. rain forests- Gilea (from Greek hile - forest). From the plane, they resemble the green sea (ill. 23).
In the zone of humid equatorial forests, rivers are always full-flowing. During floods, they often flood low banks, and water covers vast expanses.
Under the conditions of the equatorial forest, red-yellow ferrallitic soils (from lat, ferrum - iron) were formed. It is iron compounds that give them their red color. These soils are very poor in nutrients, because organic residues are quickly decomposed by microorganisms due to high humidity and heat, and nutrients quickly absorbed by plants. Therefore, the deforestation of equatorial forests causes an ecological catastrophe. The soil in the bare areas is washed away by rains, and the sun turns the surface of the earth into a dry crust, where nothing can grow.
There are over 25,000 plant species in the equatorial forests of Africa. Only trees - almost 1000 species. These forests are always stuffy, humid and dark. The forest is so dense that it is impossible to see something nearby: there are bushes around, trees braided with vines, fallen giant logs.
Rice. 23. Moist equatorial forest
Rice. 24. Layered African hylaea
The equatorial forest has two characteristic features: it is evergreen and multi-tiered.
An evergreen forest because the plants never completely shed their leaves. Due to warm and humid weather throughout the year, the leaves can exist on the shoot for 2-3 years.
Layering is the distribution of plants in height in accordance with the need for light.
In forests temperate zone 3-4 tiers of plants. There are 6-8 of them in gelae (Fig. 24)! Below - the realm of shade-tolerant mosses and creeping plants. Shrubs and young trees, unpretentious to light, rise above. There are many tree ferns, bananas. Even higher grow trees 15-20 m tall, which need more light. Among them are many valuable breeds such as redwood, ebony, sandalwood, yellowwoods. There are also grain, nutmeg trees. Ficuses and various types of palm trees reign even higher. There are light-loving seibi trees that are tall, with spreading crowns reaching 60-80 m. In such tall trees, the leaves are hard and evaporate little water. After all, it is difficult to raise it to such a height even for the most powerful root system. Wide root supports help keep the trunk upright.
The branches of the trees of the lower tier are intertwined so tightly that the crowns of the trees of the upper tier are not visible through them. At the very surface of the earth there is complete darkness. Only 1/120 of the sunlight gets here, so there is no grass at all. But creepers rise from the ground - trees with a flexible and long (up to 300 m) stem, which, wrapping around the trunks, bring leaves and flowers to the light. It is difficult and dangerous to make your way through such a forest without a path.
African hylaea is the birthplace of valuable economic tree species: coffee tree, oil palm. Cocoa is also cultivated here.
The fauna of the humid equatorial forests is rich and varied.
All tiers of the forest are inhabited. Great apes live here - gorillas and chimpanzees. A real giant is a two-meter gorilla (Fig. 25) with thick black hair. She has great physical strength. He spends most of his life on the ground, although from time to time he climbs trees. A chimpanzee is smaller than a gorilla (height is up to 1.5 m), has a large brain volume, and is characterized by complex behavior. Lives in trees. Of the other monkeys, monkeys and baboons are known.
Rice. 25. Gorilla
Rice. 26. Okapi
A variety of birds flutter among the trees: fruit dove, various types of parrots, hornbills, woodpeckers, sunbirds, bananas. A lot of insects: termites, mosquitoes, beetles, butterflies, bees, dragonflies, scorpions, spiders. Some insects are dangerous to humans: malarial mosquitoes carry pathogens of tropical fever, tsetse flies - sleeping sickness.
Terrestrial animals include lizards, shrews, earth vipers, pythons, whalers and forest pigs, African deer (40 cm high), and forest antelopes. To the amazing creatures of nature, the okapi (Fig. 26) is an animal with striped hind limbs, like a zebra. In fact, this is a pygmy giraffe, three times lower than its tall relative. Occasionally there is a pygmy hippopotamus, which weighs 10-12 times less than a real one.
As if a giant chain envelops moist equatorial forests from the north and south, a zone of variable-humid forests. This is a transitional zone from moist equatorial forests to open savannahs. The flora and fauna of this zone are similar to the equatorial forest, but the rhythm of their life is determined by the seasons (wet and dry).
Variable- moist forests mastered by man more than the equatorial ones. The population living near or in the forests themselves is not numerous. Local tribes are engaged in hunting and fishing. Large areas of forests are cut down for valuable tree species. Animals die along with the forest.
Briefly about the main thing!
In Africa, the latitudinal zonality of natural zones is clearly traced, which is mirrored on both sides of the equator. The main natural zones of the mainland are humid equatorial forests (hylaea), savannahs and light forests, tropical deserts and semi-deserts.
The humid equatorial forests of Africa grow mainly on the coast of the Gulf of Guinea and in the Congo River basin in warm and humid conditions. equatorial climate. Nutrient-poor red-yellow ferralitic soils have formed here.
Moist equatorial forests are evergreen and multi-tiered. They amaze with richness of vegetation.
The most common representatives of the animal world are monkeys (gorillas, chimpanzees, monkeys), birds (parrots, hornbills, sunbirds, bananas), and numerous insects.
1. What are the features of the change of natural zones in Africa?
2. Name and show on the map the main natural areas of the mainland.
3. What kind of soils were formed in the gelae?
4. Name the representatives of flora and fauna of the zone of humid equatorial forests.
5. Think about how plants have adapted to living conditions in humid equatorial forests.
would. Do you think that animals that live in humid equatorial forests can survive if they are relocated to temperate forests? Justify the answer.
Africa is an amazing continent, where a large number of geographical zones are combined. Nowhere else are these distinctions so visible.
The natural areas of Africa are very clearly visible on the map. They are distributed symmetrically about the equator and depend on uneven precipitation.
Characteristics of the natural zones of Africa
Africa is the second largest continent on Earth. It is surrounded by two seas and two oceans. But the most main feature- this is its symmetry in position in relation to the equator, which divides Africa into two parts along the horizon.
Hard-leaved evergreen moist forests and shrubs are located in the north and south of the mainland. Next come deserts and semi-deserts, then savannahs.
In the very center of the continent there are zones of variable-moist and permanent-moist forests. Each zone is characterized by its climate, flora and fauna.
Zone of variable-moist and humid evergreen equatorial forests of Africa
The zone of evergreen forests is located in the Congo Basin and runs along the Gulf of Guinea. Over 1000 plants can be found here. In these zones, predominantly red-yellow soils. Many types of palm trees grow here, including oilseeds, tree ferns, bananas, and creepers.
Animals are placed in tiers. In these places, the animal world is very diverse. A huge number of shrews, lizards and snakes live in the soil.
A huge number of monkeys live in the zone of humid forests. In addition to monkeys, gorillas and chimpanzees, more than 10 species of individuals can be found here.
Dog-headed baboons cause a lot of anxiety to local residents. They are destroying the plantations. This species is distinguished by ingenuity. They can only be frightened by weapons, they are not afraid of a person with a stick.
African gorillas in these places grow up to two meters and weigh up to 250 kilograms. Elephants, leopards, small ungulates, forest pigs live in the forests.
Good to know: The tsetse fly lives in the eucalyptus regions of Africa. It is very dangerous for humans. Its bite infects with deadly sleeping sickness. The person begins to worry strong pain and fever.
savannah zone
About 40% of the entire territory of Africa is occupied by savannahs. The vegetation is represented by tall grasses and umbrella trees towering above them. The main one is the baobab.
This is the tree of life, which is of great importance to the people of Africa. , leaves, seeds - everything is eaten. The ash from the burnt fruit is used to make soap.
In dry savannahs, aloes grow with fleshy and prickly leaves. In the rainy season, the savannah is very abundant vegetation, but in the dry season it turns yellow, fires often occur.
The red soils of the savannah are much more fertile than those in the rainforest zone. This is due to the active accumulation of humus during the dry period.
In the territory African savannah inhabited by large herbivores. Giraffes, elephants, rhinos, buffaloes live here. The savannah area is the habitat of predators, cheetahs, lions, leopards.
Tropical and semi-desert zones
Savannahs are replaced by zones of tropical deserts and semi-deserts. Precipitation in these places is very irregular. In certain areas, it may not rain for several years.
The climatic features of the zone are characterized by excessive dryness. Often occur sandstorms There are significant temperature differences throughout the day.
The relief of the deserts is a placer of stones and salt marshes in those places where once there were seas. There are practically no plants here. There are rare spines. There are types of vegetation with short term life. They grow only after the rains.
Zones of evergreen hard-leaved forests and shrubs
The most extreme zone of the continent is the territory of evergreen hard-leaved leaves and shrubs. These areas are characterized by wet winters and hot dry summers.
Such a climate favorably affects the condition of the soil. In these places it is very fertile. Lebanese cedar, beech, oak grow here.
In this zone, the highest points of the mainland are located. On the peaks of Kenya and Kilimanjaro, even in the hottest period, there is always snow.
Table of Natural Areas of Africa
The presentation and description of all the natural zones of Africa can be visualized in the table.
| Name of the natural area | Geographic location | Climate | Vegetable world | Animal world | The soil |
| Savannah | Neighboring zones from equatorial forests to the north, south and east | subequatorial | Herbs, cereals, palms, acacias | Elephants, hippos, lions, leopards, hyenas, jackals | Ferrolitic red |
| Tropical semi-deserts and deserts | Southwest and north of the mainland | Tropical | Acacias, succulents | Turtles, beetles, snakes, scorpions | Sandy, rocky |
| Variable-humid and humid forests | north of the equator | Equatorial and subequatorial | Bananas, palm trees. coffee trees | Gorillas, chimpanzees, leopards, parrots | brown yellow |
| Hardwood evergreen forests | Far north and far south | Subtropical | Arbutus, oak, beech | Zebras, leopards | brown, fertile |
Position climatic zones mainland is very clearly demarcated. This applies not only to the territory itself, but also to the definition of fauna, flora and climate types.
Equatorial rainforests
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 expressed. Drops out at least 1500 mm precipitation, since here the area reduced pressure(see Atmospheric pressure), 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 lush evergreen vegetation with a complex layered structure of the forest. 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 rain. In plants of the lower tier, the leaves, on the contrary, are thin and delicate.
equatorial forests South America called selva (port. - forest). This zone here occupies much larger areas than in Africa. 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).
The equatorial forest is the birthplace of many valuable plants such as the oil palm, from 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, to Madagascar.
The main share of equatorial forests is located in Africa and South America, but they are also found in Eurasia, mainly on the islands. As a result of significant deforestation, the area under them is sharply reduced.
equatorial forests
Moist evergreen forests are located in narrow bands and patches along the equator. "Green Hell" - this is what many travelers of past centuries called these places, who had to be here. High multi-tiered forests stand like a solid wall, under the dense crowns of which dusk, monstrous humidity, constant heat, there is no change of seasons, showers regularly fall in an almost continuous stream of water. The forests of the equator are also called permanent rainforests. The traveler Alexander Humboldt called them "hylaea" (from the Greek hyle - forest - approx. from geoglobus.ru). Most likely this is what the wet forests looked like. carboniferous period with giant ferns and horsetails. Subequatorial forests are distinguished by the fact that among evergreens there are also those that drop their leaves for several weeks a year.
Life in the rainforest is located "vertically" - plants and animals occupied different "high-rise floors" of this wonderful world adapting to its conditions. In such forests there can be up to five such levels.
The upper floors are at a height of up to 45 m and do not have a closed cover. As a rule, the wood of these trees is the most durable. Below, at a height of 18-20 m, there are tiers of plants and trees that form a continuous closed canopy and almost do not let the sunlight down to the ground. The rarer lower belt is located at a height of about 10 m. Shrubs and herbs grow even lower, such as pineapples and bananas, ferns. Tall trees have thickened overgrown roots (they are called plank-shaped), helping the gigantic plant maintain a strong connection with the soil.
What plants grow in equatorial forests?
Such plants are called "epiphytes", i.e. living at a distance. Such, for example, orchids. Their exquisite flowers with an intoxicating aroma are nothing more than an attempt in a tough competitive struggle to attract insects and birds for pollination and thus support their future life. In the depths of the forest, in constant dampness, the largest flower on the planet, Rafflesia Arnoldi, blooms, exuding a heavy smell of rotting meat. Its flower reaches a diameter of 1 m.
In a warm and humid climate, the decomposition of dead plants occurs very quickly. From the resulting nutrient composition, substances are taken for the life of the gilea plant.
The rainforests of South America are called "selva". In my own way species composition(the number of plant species is 2500-3000) The Amazon selva ranks first in the world. Not much, but still inferior to her African equatorial forests. The land in the rain forest is the realm of mosses, mushrooms, algae, plants with broad leaves that catch and retain moisture, insects, including poisonous ones. To survive in the jungle, travelers need the knowledge of local residents who build houses on stilts and sleep in hammocks.
All habitual life is concentrated "between heaven and earth", on the wide branches of trees intertwined with vines. Among such landscapes flow the most full-flowing rivers of our planet - the Amazon in the selva of South America, the Congo in Africa, the Brahmaputra in Southeast Asia.
Selva of the Amazon, as well as the equatorial forests of the Congo, Guinea, Uganda, the forests of the equatorial islands of Oceania, going to the sea coasts, create amazing natural communities- mangrove forests. The aerial roots of plants in such a forest are in themselves impenetrable thickets. Numerous aerial roots trap every opportunity to get air, making their way from wet sand and liquid mud, and at high tides - from sea water. The width of such a mangrove border can reach 10-20 meters.
The equatorial forests of our planet are often called its lungs. Indeed, a huge number of hylaea trees emit such an amount of oxygen into the atmosphere that their reduction threatens humanity with a significant deterioration in the composition of the air. Some of the rainforests have already been cleared. In their place, man cultivates various crops, including coffee, oil and rubber palms.
Flora and fauna Tropical Africa
The vegetation in Africa is rich and varied. Its nature is determined by the amount of precipitation and the duration of the wet season due to the flat relief and the position of the mainland between the tropics. In the equatorial climate zone species-rich evergreen multi-tiered forests grow. Herbaceous vegetation predominates in subequatorial belts. AT tropical zones vegetation is poor in species, sparse or absent altogether.
Equatorial climate zone
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Plants of equatorial forests. Features and meaning
Plants of equatorial forests cannot but arouse increased interest not only among specialists, but also among ordinary inquisitive travelers from all over the world. And there is nothing surprising in this.
Agree, many of us tend to visit overseas countries precisely for the sake of these exotic representatives of the flora. For example, the plants of the equatorial forests of South America or Africa are very different from those herbs, flowers, trees and shrubs that we are used to seeing outside the window of our hometown. They look, smell and bloom completely differently, which means they cause mixed emotions. They want to take a closer look, touch and photograph.
Plants of the equatorial forests is a topic that can be talked about indefinitely. This article aims to acquaint readers with the most characteristic properties and living conditions of these representatives of the world of flora.
general information
First of all, let's try to define such a concept as humid equatorial forests. Plants whose habitats are regions with a pronounced equatorial, subequatorial and tropical climate inhabit this type of natural zone. It is worth paying attention to the fact that in this case, not only herbs, but also numerous trees and shrubs can be attributed to various kinds of representatives of the flora.
At first glance, it's hard to even imagine, but there is up to 2000 or even 10,000 mm of precipitation per year.
These land areas are characterized by huge biodiversity, it is here that 2/3 of all plants and animals of our planet live. By the way, not everyone knows that millions of species are still not described.
On the lower tier in tropical rainforests, there is not enough light, but the undergrowth, as a rule, is weak, so a person can easily move along it. However, in the event that for some reason the deciduous canopy is absent or weakened, the lower tier can quickly become covered with impenetrable thickets of vines and intricately woven trees. This is called the jungle.
The climate of the equatorial forest
Animals and plants of the equatorial forests, as we have already said, are diverse. This is due to the prevailing climate, which means that we need to talk about it in more detail.
This zone stretches along the equator with a shift to the south. The average year-round temperature is 24-28 degrees. The climate is quite hot and humid, although the seasons are implicitly expressed.
This area belongs to the area of low pressure, and precipitation here falls evenly throughout the year. Such climatic conditions contribute to the development of evergreen vegetation, which is characterized by the so-called complex structure of the forest.
Related videos
The flora of the equatorial territories of the planet
As a rule, moist evergreen forests, located in narrow stripes or peculiar spots along the equator, are diverse and have a huge number of species. It is difficult to imagine that today there are more than a thousand of them only in the Congo Basin and on the coast of the Gulf of Guinea.
Plants of the equatorial forests of the upper tier are represented by giant ficuses and palm trees, of which there are over 200 species. In the lower ones, mainly bananas and tree ferns grow.
The largest plants are often entwined with vines, blooming orchids. By the way, it is worth noting that sometimes in the equatorial forests there are up to six tiers. Among the plants there are also epiphytes - mosses, lichens, ferns.
But in the depths of the forest you can find the largest flower of our planet - Rafflesia Arnoldi, the transverse diameter of which reaches 1 meter.
Fauna of the equatorial forest
It is unlikely that anyone will be surprised if we note that the fauna of the equatorial forests, first of all, is rich in monkeys. Monkeys, chimpanzees, gorillas, howler monkeys and bonobos are especially common and in huge numbers.
Of the land inhabitants, you can often meet small ungulates, for example, in Africa, tourists often admire okapi, African deer and other unusual animals. The most common predators of the selva of South America, of course, are the jaguar and puma. But in the African tropics, the owners are fast leopards and huge tigers.
Due to the humid environmental conditions, many frogs, lizards and insects live in the equatorial forests. The most common birds are hummingbirds, parrots and toucans.
As for reptiles, who does not know about the pythons of Africa and Asia or the anaconda from the Amazon jungle? In addition, in the equatorial forests are common Poisonous snakes, alligators, caimans and others at least dangerous representatives fauna world.
What will happen if the plants of the equatorial forests are destroyed?
During the deforestation of the equatorial forest, a person, sometimes without realizing it, destroys the habitat of many animals and takes away food from termites. In addition, this forest also holds back the onset of deserts that are detrimental to all living things.
But that's not all. The fact is that humid equatorial forests, although they occupy a relatively small part of the Earth, are the so-called green lungs our planet. It is here that about 1/3 of the Earth's oxygen is produced, so the destruction of the equatorial forest will cause irreversible environmental consequences, including an increase in carbon dioxide. The latter, in turn, will lead to an increase in the average temperature, increase the likelihood of glacier melting, and therefore entail the subsequent flooding of many fertile lands.
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These interesting plants, so readily bred for the beauty of their originally built flowers and familiar to all, also belong predominantly to the tropics. Most often they come across in the mountains. equatorial belt; there you can always find a few representatives of innumerable forms of orchids. They grow along trunks, branches, along branching branches, developing especially magnificently on fallen trunks, covering rocks and cliffs from top to bottom; some, like our northern species, grow on the ground between other herbs. Many trees, the bark of which is especially conducive to the growth of orchids, are completely covered with them and thus form, as it were, natural orchid gardens. Some orchids are particularly fond of the rotted petioles of palm leaves and tree ferns. Many grow most readily near the water, while others, on the contrary, need air and the light of high tree tops. Everyone knows the original diversity of the structure of orchids and the beautiful colors of their flowers, but our richest orchid collections do not give any complete idea of the whole multitude of their species that come across under the tropics; however, many of them have flowers too plain to be worth breeding. More than 30 years ago Lindley (Lindley) estimated the number of orchid species known at that time at about 3000, Bentham and Hooker in Genera plantarum estimate them already at 5000; it is very likely that in our time the number known species orchids reaches 6000.
Vegetation of the equatorial forests
But no matter how great the number of species already collected and described, the number still to be discovered must be colossal.
Orchid Grammatophyllum speciosum (Java)
In contrast to ferns, individual species of orchids have a relatively small distribution; therefore, for an exhaustive acquaintance with all the species belonging to only one more or less extensive area, for example, an island the size of Java, many years of work by a good botanist would be required. It is very possible that this remarkable family will eventually prove to be the most species-rich of all the flowering plants.
Despite the fact that any orchid can be recognized by its peculiar appearance, even not during flowering, yet both their size and appearance are extremely diverse. Some small climbing species do not exceed moss in size, while the large Grammatophyllum from the island of Borneo, growing in the forks of tree branches, have densely leafed trunks up to 10 feet long; some terrestrial species, such as the American Sobraliae, reach the same size. Most orchids look extremely peculiar due to their fleshy aerial roots, which often hang far down, crawl along rocks, or are slightly attached to the bark of a tree; They feed on rainfall and atmospheric moisture in general. Despite so many various kinds orchids in the equatorial forests, their flowers are relatively few striking. This is partly because in many orchids they are generally inconspicuous, and partly because the flowering time of each species lasts only a few weeks and falls on different months for different species. In addition, the very type of growth of orchids, which are found in most cases separately, in separate specimens or in groups that rarely reach a large size and therefore do not stand out among the mass of plants surrounding them, also has an influence. Only rarely does a traveler find himself in a place where orchids remind him of the beauties of our orchid greenhouses and exhibitions. Slender golden Oncidiae of the flooded forests of the upper Amazon, magnificent Cattleya of drier forests, marsh Caelogynae, and finally, the wonderful Vanda lowii of the wooded hills of Borneo - these are the main examples of beautiful orchids, especially etched into the memory of the author of these lines during his 12 years of wandering through the tropical forests. The Vanda mentioned above stands out decisively from all orchids: from a relatively small tuft of its foliage, numerous pedicels protrude, hanging down like cords up to 8 feet long, and completely dotted with large star-shaped, red-speckled flowers.
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PandanusesBamboo
Tropical forests are overflowing with flora and fauna. Representatives of ancient groups of mammals have been preserved here - the most primitive marsupials - possums, woolly wings. Also in the forests there is a multiple variety of monkeys and semi-monkeys (lemurs, lorises). The lizards of the Old World and the armadillos and anteaters live in the tropical forests. Among the birds that live in the crowns, there are many that do not fly very well, but mostly jump and climb (toucans, turacos, hornbills, birds of paradise). And Nicobar pigeons, crowned pigeons, bowerbirds are excellent flyers, and parrots (cockatoo, macaws, Amazon, Jaco) climb well and fly. Tree-dwelling animals can be divided into two groups: gliders, which have a well-developed flying membrane (large flying possum, woolly wing, spiny tail) and climbers, which, in addition to strong and dexterous paws, have a tenacious tail used as a fifth full-fledged limbs (kinkajou, anteaters, howler monkeys, pangolins). Among them are leaf-eating (sloths, colobus), frugivorous forms (gulda, kalong, little flying fox, kinkajou) and animals with a wider range plant food(monkeys, ratuf, woolly wing, kangaroo, spiketail). Others, such as the gorilla, mandrill, porcupine, although they can climb trees, are often found on the ground. Insects, goulda, kalong, little flying fox, some birds are pollinators of rainforest flowers. There are also the most large inhabitants tropics, which control the number of animals - these are jaguars, leopards and tigers. The boa constrictor, which can swallow prey whole, is also very dangerous. It could be like big monkey, and a small hippo.
Trees in tropical rainforests have several general characteristics, which are not observed in plants of less humid climates.
The base of the trunk in many species has wide, woody ledges. Previously it was assumed that these ledges help the tree to maintain balance, but now it is believed that water with dissolved nutrients flows down these ledges to the roots of the tree. Broad leaves are also common in lower forest trees, shrubs and grasses. Tall young trees that have not yet reached the topstory also have broader foliage, which then decreases with height.
Plants of equatorial forests. Moist equatorial forests
The wide leaves help the plants absorb sunlight better under the tree edges of the forest, and they are protected from the wind from above. The leaves of the upper tier, forming a canopy, usually smaller size and heavily indented to reduce wind pressure. On the lower floors, the leaves are often tapered at the ends so that this allows the water to drain quickly and prevents microbes and moss from growing on them that destroy the leaves.
The tops of trees are often very well connected with each other with the help of vines or plants - epiphytes, fixed on them.
Other characteristics of the tropical rainforest are unusually thin (1-2 mm) tree bark, sometimes covered with sharp thorns or thorns; the presence of flowers and fruits growing directly on tree trunks; a wide variety of juicy fruits that attract birds, mammals and even fish that feed on the sprayed particles.
In humid tropical forests, there are edentulous (families of sloths, anteaters and armadillos), broad-nosed monkeys, a number of families of rodents, bats, llamas, marsupials, several orders of birds, as well as some reptiles, amphibians, fish and invertebrates. Many animals with tenacious tails live on trees - tenacious monkeys, pygmy and four-toed anteaters, opossums, tenacious porcupines, sloths. A lot of insects, especially butterflies (one of the richest fauna in the world) and beetles; many fish (as many as 2000 species - this is approximately one third of the freshwater fauna of the world).
In the very center of Africa in the basin of the great African river Congo to the north and south of the equator line and along the shores of the Gulf of Guinea are the humid equatorial forests of Africa. The forest zone is located in the equatorial climate zone. It is hot and humid here all year round. Usually in the morning the weather is hot and clear. The sun rises higher and bakes more and more. As the temperature rises, evaporation increases. It becomes damp and stuffy, like in a greenhouse. In the afternoon, cumulus clouds appear in the sky and merge into heavy lead clouds. The first drops fell, and a violent thunderstorm broke out. It rains for an hour or two, sometimes more. Rushing streams of rainwater rush through the forest. Countless streams merge into wide rivers. By evening the weather clears up again. And so almost every day from year to year.
There is an abundance of water everywhere. The air is saturated with moisture, plants and soil are saturated with water. Vast areas are swampy or subject to flooding. The abundance of heat and moisture favors the lush development of dense evergreen woody vegetation. Plant life in the equatorial forests never stops. Trees bloom, bear fruit, shed old foliage and put on new ones throughout the year.
Eternal twilight reigns under the multi-storey green vault of the forest. Only in some places a ray of the sun breaks through the foliage. Oil palm grows in bright places. The palm vulture likes to eat its fruits. 100 or more species of trees can be counted on 1 hectare of the equatorial forest. Among them are many valuable species: ebony (ebony), red, rosewood. Their wood is used to make expensive furniture and is exported in large quantities.
The forests of Africa are the birthplace of the coffee tree. Bananas are also indigenous Africans. And the cocoa tree was brought here from America. Large areas are occupied by plantations of cocoa, coffee, bananas, pineapples.
Most animals have adapted to life in trees. Mammals are characterized by a variety of monkeys. The lord of the African equatorial forest, the world's largest ape - the gorilla. The favorite food of gorillas is the core of banana stalks. There are very few gorillas left and hunting for them is strictly prohibited. There is a forest antelope bongo, an African wild boar, in the depths of the forest you can meet a very rare hoofed animal akapi. Of the predators, there is a leopard, which climbs trees perfectly.
The world of birds is very rich: kalao - a hornbill, a parrot, a Congolese peacock, tiny sunbirds that feed on flower nectar. Many snakes, incl. poisonous, chameleons that feed on insects.
The inhabitants of the equatorial forest zone are excellent hunters. The significance of hunting is all the more great because the development of cattle breeding is hindered by the spread of the tsetse fly. The bite of this fly is detrimental to livestock and causes severe illness in humans. Rivers abound in fish. And fishing is more important than hunting. But swimming is dangerous. There are many crocodiles here.
Africa is one of the largest continents of the Old World, the second largest after Eurasia. Its area with islands is 30.3 million km 2.
The total forest area is 826.1 million hectares (or 8.26 million km 2). The average forest cover is 27.5%. According to the nature of forests and the degree of forest cover, Africa is divided into four major district(or areas): Northern - subtropical, Western - tropical (most forested), Eastern - mountainous tropical and Southern - subtropical.
For northern region, which includes the forests of Morocco, Algeria, Tunisia, Libya and ARE, are characterized subtropical forests along the slopes of the Atlas Mountains, valleys, plateaus and the southern coast of the Mediterranean Sea.
Hard-leaved evergreen forests and maquis grow in the lower part of the slopes, dominated by holm and cork oaks, Atlantic pistachio, strawberry tree, tree-like heather, wild olive, jujube, etc.
Higher in the mountains grow forests of Aleppo pine, the most widespread in Algeria and Tunisia, and even higher (from 1300 to 2300 m) - coniferous, quite productive forests of Atlas cedar, maritime pine, juniper and sandarak tree. Plots of cedar forests often have a timber reserve of 300-350 m 3 / ha and an annual increase of 2.5-3 m 3 / ha.
Cork oak forests occupy relatively large areas and are concentrated along the northern slopes of the mountains and along the coast. In Morocco, they are distributed over an area of more than 370 thousand hectares and annually produce 15-18 thousand tons of cork. In Algeria, the area of cork oak forests is 440,000 ha, and 35,000 to 40,000 tons of cork are harvested here annually. In Tunisia, such forests occupy about 120 thousand hectares, and the annual harvesting of cork is approximately 5 thousand tons. The average forest cover of the region is 1.6% and ranges from 0.3% in Libya (excluding the ARE, where there are almost no natural forests) up to 12.3% in Morocco. Artificial forests in these countries occupy approximately 120 thousand hectares and consist of plantations of eucalyptus, various acacias, pines and poplars.
The total volume of timber harvesting in the region is 6.6 million m 3, including in Morocco - 2.9 million m 3, in Algeria - 1.3 million, in Tunisia - 1.8 million, in Libya - 0.4 million and in Egypt - 0.2 million m 3.
The bulk of the blanks is firewood, and industrial wood is 13-14%. The total import of industrial timber is 350 thousand m 3 (Morocco - 220 thousand m 3).
Most Valuable forest areas in North Africa include 17 national parks and 93 nature reserves. Of these, Morocco has two national parks - Tazzeka and Toubkal, where areas of Atlas cedar, evergreen oaks (including cork), juniper and endemic fauna - mouflon, maned sheep, mountain gazelle, etc. are preserved.
In Algeria, in a number of parks - Akfadou, Babor, Jebel Guraiya, Dzhur Dzhura, Warsenis - Atlas cedar, Alep pine, sandarac tree, Mirbek oak and cork, Numidian fir and endemic fauna are also preserved. In Tunisia, in the Jebel Bou Hedma park, areas with gum acacia and alpha grass are preserved.
In the Western Tropical Region, the most valuable are the green equatorial evergreen forests. They are concentrated in two large areas along the coast of the Gulf of Guinea and occupy the southwestern and southern regions of the territories of Senegal, Gambia, Guinea-Bissau, Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana, Togo, Benin, Nigeria, Cameroon, Central -African Republic, Equatorial Guinea, Gabon, as well as the northern parts of the Congo, Zaire and Angola. The total area of closed forests is about 170 million hectares. Over 3,000 species of trees and shrubs are distributed in them (over 1,000 species of trees, often reaching a height of 40-50 m). More than 40 species have valuable wood, such as ebony, santal, red, high lofira, high chlorophora, or iroko, and regal chlorophora, kaya; several types of entandophragma - sipo, sapeli, tyama, kosipo; fragrant guards, avodira, lush terminalia, or limbo, as well as framirae, Haeckel's mimusops, uapaca, okume and many others.
According to the studies of A. Obreville, virgin evergreen forests survived only in the remote mountainous regions of Cameroon, in the basins of the upper tributaries of the Congo (Zaire) away from roads, in areas where slash-and-burn agriculture was not carried out. In a significant part of the territory of the zone of moist equatorial forests, derivative, or secondary, forests are widespread. In their composition, trees with soft wood predominate, the stand is less productive. These are the iroko, limbo, framiré, illomba, oil palm, oil tree, or butyrospermum, and guinea ceiba groups. Palm trees are found in the river valleys, coconut palm groves along the sea coast, and mangrove forests in areas of gentle, silty ocean shores.
To the south and north of the moist equatorial forests stretch variable-humid, partially deciduous tropical forests. They are characterized by lush terminalia, high chlorophora, as well as brilliant baffia, or Angolan tree, hard-resin triplochiton, or obech, Angolese pterocarpus, high monsonia, copal tree, brilliant cola, Guinean olive, oil tree, fuzrugoz ebony, African mimosops, or duka, etc. The most extensive areas of variable-moist tropical forests are found in the Congo, Zaire, Angola, as well as in the Central African Republic, Cameroon, Nigeria, the Ivory Coast and Guinea.
To the south of the zone of variable-humid deciduous tropical forests in the Western region, dry closed and sparse forests are common. They are heterogeneous in composition and productivity. In closed forests of the “mabwati” type, common in Zaire and in the east of Angola, burkea, huapaca, isoberline, mahogany, African afselia, or lingua, etc. predominate. Legumes (types of isoberline) and brachystegia, there are various acacias and a copal tree.
In the northern part of the Western region stretches a zone of tropical savanna sparse forests. They occupy southern Mauritania, northern Senegal, Guinea, Ivory Coast, Ghana, Togo, Upper Volta, northern Benin, Nigeria, Cameroon and the Central African Republic. Savanna forests and acacia savannas are southern parts Mali, Niger, Chad, which are also included in the Western region, and penetrate into the Eastern region in the territory of Sudan, Ethiopia, Kenya, Tanesh. Uganda and Somalia, alternating with tropical xerophilous woodlands and shrubs.
In these dry sparse forests with a lot of acacias, baobabs, oil trees, oilseeds, you can often find groups of trees whose main tree canopy consists of bauginia, parkia, large-winged tesminalia, blue germinalia, senegalese kaya, African mimosa, kapok tree, African piptadenia, tofnra lanceolate. There are two types of coffee tree, which have become the initial forms for many zeultury varieties. Strophanthus liana and rubber-bearing landolphia also grow here.
The total area of savanna forests and acacia savannas in the Western region is 316.5 million hectares.
Protected forest areas in the Western region are represented by 30 national parks and 75 reserves with a total area of about 25 million hectares. They preserve the most characteristic forest landscapes (wet evergreen, deciduous, dry forests, forest savannas and savanna forests). different types) with a particularly remarkable fauna. These are great apes - gorillas and chimpanzees (Duala Edea Park), giraffes, elephants, buffaloes, ostriches, marabou, rhinos, antelopes, lions, leopards, crocodiles. Here are the parks Vaza, Benue, Bubanjida - in Cameroon; Nimba - on the territory of Guinea and the Ivory Coast; Double "B" ("W") - in the territory of Benin, Upper Volta and Niger, etc.
In the Iona National Park, which is located in the Namib Desert (Angola), the original gymnosperm "tree" is preserved - amazing velvichia, which has a trunk up to 0.5 m high and two perennial leaves. Angola has planned forestry and great work on the introduction of tree species (mainly conifers) in order to sharply increase the productivity of forests.
For the Eastern region of Africa, valuable evergreen tropical forests are most characteristic. Their total area (approximately) is 3.5-4.0 million hectares. They are common in Kenya, Tanzania, Uganda, Rwanda, Burundi, Mozambique, Ethiopia, and also in the eastern part of Madagascar. Particularly famous here are such species as okotea, or East African camphor tree, ebony, brahilena, Zanzibar copal tree, high chlorophore. In the mountains (2100-2700 m) of Ethiopia, Kenya, Rwanda, coniferous forests grow from slender juniper, close to our J. excelsa, various podocarpus with an admixture of broad-leaved deciduous species.
In Kenya, coniferous forests occupy about 800 thousand hectares, and above them forests of large bamboo extend, occupying about 200 thousand hectares. In the mountains of Malawi (on the border with Zambia) at an altitude of 1800-2000 m, there are patches of coniferous forests (2 thousand hectares) from White's widdringtonia.
The total area of closed forests in the Eastern region of Africa is 19 million hectares, savannas and savannah forests - 232.5 million hectares.
More than 40 national parks (12.5 million ha), 90 forest reserves and over 450 forest reserves (15 million hectares). These are the reserves of Madagascar, where moist mountain forests, tropical rainforests with a "tree of travelers", tamarind and endemic fauna (lemurs, etc.) are protected; national parks of Kenya: Aberdare, Ambose-li, Tsavo - with park savannas represented by baobab, tree-like euphorbia, endemic acacias, mountain savanna and acacia forests with original fauna - lions, giraffes, gazelles, antelopes, hippos, buffaloes, etc. ; national parks of Tanzania, including the Serengeti (1.5 million hectares) with acacia savannah and original fauna (lions, cheetahs, elephants, giraffes, zebras); crater Ngo-rongoro (780 thousand hectares) with mountain wet tropical forests in which black rhinos, leopards, etc. are found; highest mountain Africa's Kilimanjaro (5895 m) with picturesque landscapes, as well as the parks of Southern Rhodesia with widdringtonia, podocarpus, etc.
In the southern region of Africa, in the mountain ranges and on the coast, subtropical evergreen forests are common, in which endemics of the Cape flora have been preserved: legcarps, or podocarpus, Thunberg and elongated, bay leaf olive, Kamassa gonionoma, tree fern - bearded todea, as well as small areas of forests from widdringtonia (two species) and Haeckel's podocarpus. Among hard-leaved evergreen shrubs there are silver tree, proteaceae, heather, rhinoceros bush, etc. The total area of closed forests of the southern region of Africa is small - a little more than 250 thousand hectares, savannahs and savannah forests - 23.7 million hectares.
In the Southern region there are several national parks and reserves (about 13 million hectares). The Kruger Park (1.8 million hectares) stands out with its park savannah and valuable South African fauna (lions, leopards, cheetahs, black rhinos, giraffes, several species of antelopes, monkeys and various birds). No less interesting are the parks of Natal, Mountain Zebra, Falls Bay with mangrove and mountain forests and endemic fauna, as well as the Kalahari Gemsbok Park (900 thousand hectares) in the Kalahari Desert. A large national park - Etosha-Pan (7 million hectares) - is also in the Namib Desert (Namibia).
In addition to natural forests in Africa, forest plantations from introduced tree species are widespread, the area of which in 2009 was 2798 thousand hectares. From coniferous trees mainly pines are planted: American - radiant, Caribbean, incense, drooping, as well as Canarian and long-coniferous. Of the hardwoods, Australian eucalyptus and various acacias are especially popular.
Logging in many African countries is carried out mainly to meet local needs for fuel and household timber; their total volume - 310 million m3, including business - 54 million m3. In a number of countries (Angola, Cameroon, Congo, Gabon, Ghana, Ivory Coast, Liberia, Nigeria) valuable colored wood is harvested for export. Quite often preparations are carried out by foreign firms. In 2008, the total volume of harvesting of commercial timber for export reached 8.5 million m 3 . Research work on forestry is being carried out at a number of institutes and forest stations in the Western, Eastern, and partly Southern regions.
