Environmental problems of Africa. Man: settlement and influence on the nature of Africa In San Francisco, air from China

Human influence on nature. Back in the 19th century. Africa was presented as a continent of virgin nature. However, even then the nature of Africa was significantly changed by man. The area of ​​forests, which had been uprooted and burned for arable land and pastures for centuries, has decreased. Especially great damage to the nature of Africa was caused by European colonialists. Hunting, carried out for profit, and often for sport, led to the mass extermination of animals.

Many animals were completely destroyed (for example, some species of antelope, zebra), and the number of others (elephants, rhinoceroses, gorillas, etc.) was greatly reduced. Europeans exported expensive wood to their countries. Therefore, in a number of states (Nigeria, etc.) there is a danger of complete disappearance of forests. The territories in place of cleared forests were occupied by plantations of cocoa, oil palm, peanuts, etc. Thus, savannas were formed in place of equatorial and variable-humid forests (Fig. 59). The nature of primary savannas has also changed significantly. There are huge areas of plowed land and pastures here.

Due to poor agricultural practices (burning, overgrazing, and cutting down trees and shrubs), savannas have been giving way to deserts for many centuries. Over the last half century alone, the Sahara has moved significantly south and increased its area by 650 thousand km 2. The loss of agricultural land leads to the death of livestock and crops, and to starvation of people.

To save savannas from the onset of deserts, a wide forest belt in the Sahara, 1,500 km long, is being created, which will shield agricultural areas from the dry winds of the desert. There are several projects for watering the Sahara. Great changes in natural complexes have occurred in connection with the development of mineral resources and the development of industry.

Rice. 59. Boundaries of natural zones in Africa: A - in the past, B - modern. Using the maps, determine how the area of ​​each natural zone in Africa is changing. Which areas were hit the hardest?

Natural disasters. Natural disasters (earthquakes, droughts, floods, hurricanes, etc.) can bring enormous disasters to the population. One of Africa's most devastating natural disasters is recurrent droughts. This especially affects the population of savannas adjacent to the Sahara. As a result of droughts, people, livestock and other living organisms die. The cause of worsening droughts is the cutting down of bushes and trees, as well as excessive grazing.

Some countries suffer disasters from floods, plant diseases, and locust invasions, which can destroy the entire harvest of fields or plantations in a few hours.

Nature reserves and national parks. Currently, humanity increasingly understands the need to protect nature on Earth. For this purpose, nature reserves (territories where natural complexes are preserved in their natural state) and national parks are organized on all continents. Only people leading research work. National parks, unlike nature reserves, can be visited by tourists who are required to comply with the rules established there. In many African countries, the protection of wild animals and the most interesting natural complexes (forests, savannas, volcanic areas, etc.) is given priority great importance. Nature reserves and national parks on the mainland occupy large areas. There are especially many of them in Southern and Eastern Africa. A number of them are world famous, for example the Serengeti and Kruger national parks. Thanks to the measures taken, the numbers of many animals have now been restored.

1. Why is it important to know the geographical location of the continent? What are the features geographical location Africa?
2. Name the researchers of Africa and indicate what the role of each of them was in the study of the continent.
3. Why are Africa dominated by plains?
4. What are the features of the nature (terrain, climate, rivers, natural areas) of Africa?
5. Why is latitudinal zonation clearly visible in Africa? How does it manifest itself?
6. Based on the analysis of maps, indicate what relationship exists between climatic regions and natural zones.
7. On the map of Africa, find nature reserves and national parks, indicate which ones natural areas they are located and what the largest of them are called.
8. What activities do you think should be done in Africa to reduce disasters caused by droughts?
9. What changes have occurred in the nature of Africa due to economic activity person?

Changes in the nature of the African continent negatively affect the ecosystem of the entire planet. The rulers of states conduct policies in such a way that issues of protection environment is not given due attention. Africa's environmental problems are a global disaster.

Environmental threats

Worldwide scientific discoveries and developments in the field of environmental and environmental activities are not being implemented in African countries. There are no projects to reduce harmful emissions from industrial production into the environment. Toxic waste is not disposed of in the prescribed manner. The consequences of uncontrolled use of natural resources, overpopulation, unemployment and illiteracy are affecting the environmental situation in Africa.

Clean water shortage

One of global problems Africa - shortage drinking water. Because of this, third world countries account for 80% of infectious diseases. However, in Africa there are so many clean water that it will be enough for the population of the entire continent.

The main reserves are in Libya, Algeria and Chad.

The problem is that the water is deep underground. To extract it, the state will need tens of billions of dollars.

The governments of underdeveloped countries do not have that kind of money. There is not enough finance even to import clean water.

Cleaning problem

The continent's 55 countries have virtually no wastewater treatment facilities, with the exception of Egypt, Tunisia and Algeria. The flow of tourists forced the leaders of these states to establish a water supply system. In Egypt the source fresh water became the Nile River. But the country is not ready to share reserves with its neighbors. In the rest of Africa, 180,000 children die every year from unfiltered water and poor personal hygiene.

Deforestation

An environmental problem not only for Africa, but also for the planet is the destruction of evergreen forests. The tropics are considered the “lungs of the planet” because they produce the bulk of oxygen. Africa contains 17% of the world's forests. Every year millions of hectares of valuable species are cut down to make furniture, millions of trees are destroyed for mining palm oil.

Treeless areas are used for growing fodder crops. But such land quickly loses its fertile layer, and after 2-3 years of use it turns into a desert.

Consequences of deforestation

The decline of Africa's evergreen forests reduces rainfall. Plants slow climate change because they absorb most of the carbon dioxide from the earth's surface. Therefore, their destruction threatens not only the inhabitants of the forests themselves, but also all life on the planet.

In the equatorial belt of Africa it rains most of the year. Trees absorb rainwater and gradually release it to rivers and lakes. As vegetation is cleared, precipitation spills over the surface of the earth, causing floods. Flooding is replaced by drought. This situation leads to famine and mass death. If forest destruction is not stopped, more than 1 billion people will die from hunger over the next three decades.

Waste disposal

Every year, Europe sends ships to Africa under the guise of humanitarian aid. In fact, they are filled to the brim with toxic waste. Mostly broken electronic equipment. To recycle it, specialized plants are needed, which simply do not exist in many civilized countries. And sending garbage to Africa is cheaper.

The scale of landfills

Nigeria's largest city, Lagos, has been turned into a dumping ground. Just 25 years ago, garbage was dumped far from the city. But for last years The volume of garbage has increased, and the city has grown, and now hospitals, kindergartens, and residential buildings are located directly in the landfill.

The impact of landfills on humans

The population of Lagos is 21 million people. The landfill became a place of work for children aged 12 and older and adults. For 10 hours a day they wander through mountains of garbage in search of non-ferrous metals. Smelting is underway, and the entire city is shrouded in thick toxic smog. The permanent residents of landfills are rats, carriers of dangerous diseases.

Due to weakened immunity from air pollution and frequent outbreaks of infection, millions of people are dying in Africa.

This ecological situation is observed in all major cities African states.

Disappearance of flora and fauna

The main reason for the loss of biodiversity in Africa is environmental problems. Uncontrolled mining in prohibited areas pollutes the air. People drain swamps and cut down forests, which leads to soil erosion. Due to the reduction of forest areas, animals and plants are forced to migrate, some simply die.

To protect crops, birds of prey, ground squirrels, and coyotes are deliberately destroyed. The disruption of the food chain has led to many species of plants and animals being on the verge of extinction, and some being completely destroyed.

Poverty of the population

Environmental problems are a major factor in the poverty of the African population. Desertification of vast areas leads to famine and migration to inhabited parts of the continent. As a result, there is not enough food and clean drinking water for everyone, and clashes occur, sometimes even armed. Africa has large reserves of oil, gas and other minerals. However, 60% of the cultivated area is still cultivated with a hoe. Corruption in all government structures and reluctance to invest money in development has led to poverty and environmental disaster.

Environmental measures

Exacerbation environmental problems in Africa poses a threat to all humanity. Representatives of the UN and UNESCO, together with the governments of African countries, propose ways to solve them. At the conference in Stockholm, environmental issues were discussed with the participation of representatives from 34 African countries. The result was the creation of departments to combat environmental instability in 25 countries.

Flora protection

In some states, forest reserves are being assessed. They create reserves by restoring forest and grass cover. Pasture areas are sown with grasses. In deserted areas, where improvement of pastures does not produce results, they switch to nomadic cattle breeding. Cultivated areas have been taken under control. Land cultivation technologies are being introduced that do not lead to depletion of the soil composition. Rational irrigation of crops is monitored.

Fauna protection

To stop the extermination of animals, nature reserves are being created on the African continent. Since the 2000s, 4% of Africa has been protected. Industrial mining and forestry activities are not carried out on these lands. National parks preserve historical monuments, protected areas, flora and fauna.

World Heritage

Of the 601 protected areas, 26 belong to the World Heritage of Humanity. This list includes the following objects:

• Serengeti Park;
• Ngorongoro;
• Tassili-Ajer;
• Pelvis;
• Toubkal.

Monuments of the Sahara are also taken under protection. For more than 10 thousand years, the desert area had a humid climate, and the lands were covered with lush grasses. Before today Only rock paintings of the inhabitants of that time have survived.

Measures at the legislative level

Since 1986, laws have been adopted to protect the environment. Conferences are convened annually to discuss pressing environmental problems and propose measures to eliminate them. Large-scale awareness-raising events are being carried out on the importance of environmental conservation. Some countries have a forest law that provides for 2 years imprisonment or a large fine for burning forests.

Today, the sad truth is no longer a secret to anyone - our planet is in danger, and plants and animals have to survive in conditions of anthropogenic pollution. Even photographs that appear in the press from time to time are not able to convey the seriousness and scale of the pollution problem. This review contains little-known and shocking facts that make it possible to understand the seriousness of the problem.

1. 3 million plastic bottles

Earth
Every year, more than 6 billion kilograms of garbage are dumped into the world's oceans. Most of this trash is plastic, which is toxic to marine life. In America alone, 3 million are thrown away every hour. plastic bottles. But each such bottle decomposes within 500 years.

2. “Garbage Continent”

Pacific Ocean
Few people know about this, but Pacific Ocean there is an entire “continent” of plastic waste known as the Great Pacific Garbage Patch. According to some estimates, the size of this plastic “garbage continent” could be twice the size of the United States.

3. 500 million cars

Earth
There are more than 500 million cars in the world today, and by 2030 this number is expected to rise to more than a billion. This means that pollution caused by cars could potentially double in 14 years.

4. 30% of the world's waste

USA
Americans make up only 5% of the world's population. At the same time, they produce 30% of the world's waste and use about a quarter of the world's waste. natural resources.

5. Oil spills

World Ocean
Everyone knows that massive, deadly oil spills occur after accidents with tankers or drilling rigs. At the same time, it is practically unknown that for every million tons of oil shipped there is always one ton of spilled oil (and this without any accidents).

6. Clean Antarctica

Antarctica
The only relatively clean place on Earth is Antarctica. The continent is protected by the Antarctic Treaty, which prohibits military activity, mining, nuclear explosions and nuclear waste disposal.

7. Beijing air

China
The Celestial Empire is one of the countries with the most high level air pollution in the world. Simply breathing the air in Beijing increases your risk of lung cancer by exactly the same amount as smoking 21 cigarettes a day. In addition, nearly 700 million Chinese (about half the country's population) are forced to drink contaminated water.

8. Ganges River

India
Water pollution is even worse in India, where nearly 80% of all urban waste is dumped into the Ganges River, the most sacred river of Hindus. Poor Indians also bury their dead family members in this river.

9. Lake Karachay

Russia
Lake Karachay - a dump of radioactive waste of the former Soviet Union, which is located in the Chelyabinsk region, is the most polluted place on Earth. If a person spends just an hour in this lake, he is guaranteed to die.

10. Electronic waste

Earth
Since computers, televisions, Cell phones and other electronic devices are becoming more and more available in the world, electronic waste has been a growing problem in recent years. For example, in 2012 alone, people threw away almost 50 million tons of electronic waste.

11. A third of British fish change sex

England
Around a third of fish in British rivers change sex due to water pollution. Scientists believe that the main reason for this is hormones from waste products in wastewater, including birth control pills.

12. 80 thousand synthetic chemicals

Earth
In modern days, up to 500 have been found in the human body chemical substances, which it did not have until 1920. Today, there are a total of almost 80 thousand synthetic chemicals on the market.

13. San Francisco gets air from China

Environmental problem: light pollution.

Earth
Light pollution generally does not have a significant effect on humans, but it causes serious problems for many animals. Birds often confuse day and night, and scientists have found that light pollution can even change the migration patterns of some animal species.

Today people are looking for different ways make your life safer and production more environmentally friendly. So, .

MAN: SETTLEMENT AND INFLUENCE ON NATURE OF AFRICA

(see the map of the physical-geographical zoning of Africa with links to photographs of the nature of this region)

Africa is considered the most likely ancestral home modern man (Fig. 23).

Rice. 23. Centers of human development and ways of his settlement around the globe(according to V.P. Alekseev): 1 - the ancestral home of humanity and resettlement from it; 2 - primary western focus of race formation and settlement of proto-Australoids; 3 - settlement of proto-Europeans; 4 - settlement of protonegroids; 5 - primary eastern focus of race formation and settlement of proto-Americanoids; 6 - North American tertiary focus and dispersal from it; 7 - Central South American focus and resettlement from it.

Many features of the continent’s nature speak in favor of this position. African apes - especially chimpanzees - have, compared to other anthropoids, the largest number of biological characteristics in common with modern man. Fossils of several forms of great apes have also been discovered in Africa. pongid(Pongidae), similar to modern apes. In addition, fossil forms of anthropoids have been discovered - australopithecus, usually included in the family of hominids.

Remains Australopithecus found in the Villafran sediments of South and East Africa, i.e. in those strata that most researchers attribute to the Quaternary period (Eopleistocene). In the east of the continent, along with the bones of australopithecines, stones with traces of rough artificial chipping were found.

Many anthropologists view Australopithecus as a stage of human evolution that preceded the appearance of the earliest humans. However, the discovery of the Olduvai location by R. Leakey in 1960 made significant changes in solving this problem. In a natural section of the Olduvai Gorge, located in the southeast of the Serengeti plateau, near the famous Ngorongoro crater (northern Tanzania), the remains of primates close to australopithecines were discovered in the thickness of volcanic rocks of Villafranca age. They got the name Zinjanthropes. Below and above the Zinjanthropus, the skeletal remains of Prezinjanthropus, or Homo habilis (Habilitative Man), were found. Along with the prezinjanthropus, primitive stone products were found - rough pebbles. In the overlying layers of the Olduvai site, remains of African archanthropes, and on the same level with them - Australopithecus. The relative position of the remains of Prezinjanthropus and Zinjanthropus (Australopithecus) suggests that Australopithecus, previously considered the direct ancestors of the earliest people, actually formed a non-progressive branch of hominids that existed for a long time between the Villafranchian and the mid-Pleistocene. This thread has ended dead end.

Simultaneously with it and even somewhat earlier existed progressive form - prezinjanthropus, which may be direct and immediate ancestor of the earliest people. If this is so, then the opinion is fair that the homeland of Prezinjanthropus - the region of the continental rifts of East Africa - can be considered the ancestral home of man.

R. Leakey discovered in the vicinity of Lake Rudolf (Turkana) the remains of human ancestors, whose age is 2.7 Ma. In recent years, there have been reports of finds that are even older.

The remains of archanthropes, except for Olduvai, were found in northern Africa, in Algeria. The local name for North African archanthropes is atlantrops.

Modern man(Homo sapiens) appeared on the territory of Africa during the last, Hamblian pluvial, which corresponded approximately to the end of the last glaciation of the northern regions of the Earth.

Fossil remains of modern humans found in different areas of the continent show significant racial differences. Obviously, the main races existing in Africa at the present time emerged already in the late (Upper) Paleolithic era. Further differentiation of races continued during the Neolithic. In North Africa, judging by the bone remains, there was an ancient Caucasian type, in South Africa - the so-called Boskopian type, ancestor of modern Bushmen and Hottentots. In the west, sub-Saharan Africa itself developed Negroid(Negro) type. During the Neolithic, it was apparently formed Ethiopian contact race, and in the equatorial forests of the Congo basin a race of African pygmies developed ( Negrillian).

Modern indigenous population North Africa, including almost all of the Sahara, consists of representatives of the southern Caucasoid (Mediterranean) race, which is older than the formation of the branch of the large Caucasian race.

Anthropologically, the Caucasian population of North African countries is distinguished by a large homogeneity. It is characterized by dark skin, dark hair and eye coloring, a dolicho- or mesocephalic skull, an average height of about 170 cm. There are deviations from this type: lighter skin, Brown hair and blue eyes, which may be the result of localized depigmentation in mountainous areas with harsher climates. The southern Caucasian race belongs to the ancient Berber population North Africa and the majority of the modern population of North African countries, historically formed as a result of the Arab invasion and Arabization of the indigenous Berber population. Most of the continent south of the Sahara, with the exception of the areas adjacent to the Red Sea and the Somali peninsula, is inhabited by peoples belonging to the African branch of the great equatorial race. It contains three second order races: actually Negro (Negroid), Negrill and Bushman (Khoisan).

Traits of the Negro race proper are especially pronounced among the population of the Niger and Congo basins. These peoples have very dark skin, curly hair, pronounced prognathism, a wide nose with a low bridge, swollen lips, a dolicho- and mesocephalic head. In other areas, Negroids have deviations from these classically expressed characteristics. For example, in South-East Africa some peoples have lighter skin color, while the peoples of the Upper Nile and Senegal have almost black skin; Prognathism is expressed to varying degrees in different peoples. The differences in height are very large. The inhabitants of the Nile basin are especially tall.

At the border of the areas of southern Caucasians and Negroids, contact racial groups formed already in the Early Neolithic. This - Ethiopian race, to which the peoples of Ethiopia, Somalia and neighboring areas belong. Representatives of the Ethiopian race express almost all characteristic features Negroids, but as if in a softened form. Their skin is brown in color, but lighter than that of the most lightly colored blacks, their hair is curly and even kinky, but to a lesser extent than that of blacks, their lips are full, but not swollen, there is no prognathism, their nose is narrow, with a protruding bridge, their narrow, high face . In Western Sudan, on the border between the areas of Caucasians and Negroids, transitional forms with a combination of anthropological characteristics of both of these races also developed.

A special place within the African branch of the equatorial race is occupied by pygmies (negrilly). They live in small groups in the equatorial forests of the Congo Basin. Their average height is 141-142 cm, the maximum is 150 cm. The skin color is generally lighter than that of typical Negroids, the hair is curly, the nose is wide, with a low bridge, the mouth is wide with thin lips, facial hair is more abundant than that of tall Negroids. The fact that pygmies, on the one hand, have features that bring them closer to blacks, and, on the other hand, significant differences from the latter, suggests that these races had a common ancestor. The anthropological characteristics of the pygmies probably developed in the Neolithic under the influence of the specific natural environment of the equatorial forests, within which they still live.

Groups live in southwest Africa Bushmen and Hottentots, united according to some common anthropological characteristics into one Khoisan or South African, race, or racial group. This race also has characteristics in common with other dark-skinned Africans (wide nose and curly hair); some features bring her closer to representatives of the Mongoloid race (relatively light, yellowish-brown skin color and epicanthus); other signs are specific to the Khoisan race: accumulation of fat in the buttocks (steatopygia), severe wrinkling of the skin. The features of anthropological similarity with blacks are explained by the fact that at the early stages of development all races of the African branch had a common ancestor. Mongoloid traits do not depend on the connection with the Mongoloids, which obviously never existed and could not have existed, but on the similar environmental conditions in which these races were formed. The arid areas of the interior of South Africa are to some extent similar to those of Central Asia. This similarity, for example, explains the presence of epicanthus among the Bushmen, which is considered a characteristic feature of the Mongoloids.

The movement of peoples around the Earth, which occurred from ancient times and intensified during the era of the Great Geographical Discoveries, during the period of colonization of Africa by Europeans, led to further mixing races and the formation of mixed anthropological types. The Arab invasion of Africa, their penetration not only to the north, but also to the south, deep into the continent, into the very thick of the Negroid peoples, led to the formation of mixed types of population of South Sudan, very close in anthropological characteristics to the Ethiopian contact race.

As a result of the mixing of races in the Middle Ages, the population was formed Madagascar. It apparently developed as a result of contacts between Negroids and the Southern Mongoloids (Indonesians) who penetrated the island.

Currently there are about 800 million people. This population is distributed extremely unevenly across the continent. Vast areas are almost completely uninhabited, many are very sparsely populated. For example, in the Sahara, Kalahari, Namib Desert population density 1 person per 1 km2. The population of the tropical forests of the Congo Basin and many mountainous regions of East Africa is very low. The population density of the northern, southwestern and southeastern coasts of the mainland and the coast of the Gulf of Guinea is significantly higher. The Nile Valley in Egypt stands out especially - it is one of the most densely populated areas not only in Africa, but throughout the world. The population density there exceeds 200 people, and in some places reaches 1000 people per 1 km 2. In some areas of Africa, the highlands and mountainous areas are more densely populated than the lowlands, which have less favorable conditions for human life and activity. About 40% of the continent's total population lives at an altitude of more than 500 m above sea level.

A big problem for Africa is such natural focal diseases, like malaria, trypanosomiasis, leishmaniasis, yellow fever, schistosomiasis, etc. Many of them are associated with vector habitats (mosquitoes, tsetse flies, shellfish). In recent decades, in many African countries, especially south of the equator, widespread got AIDS. In 2001 there was a pandemic in Africa HIV infection and AIDS claimed lives 2.3 million people. The continent has the highest rate of HIV infection and the highest proportion of people living with HIV and AIDS. In 2001, there were 28.1 million people living with HIV and AIDS in sub-Saharan Africa, representing 70 % of the total number registered worldwide. Over the past 20 years, the disease has significantly affected the average life expectancy in the region, with countries such as Botswana and Malawi no longer exceeding 40 years. It is now officially believed that in Botswana 35% of the adult population are HIV-infected. Every year the number of HIV carriers and AIDS patients is growing steadily. A large role in this is played by tribal traditions that encourage early onset of sexual activity, as well as the orientation of some developing countries towards the mining industry - mining villages with many dormitories arise around the mines, in which workers isolated from their families predominate. In North African countries this problem is not so acute.

In Africa, the dominant position is occupied by rural population, the countries of this continent are the least urbanized compared to other regions of the world. IN agriculture Plantation or slash-and-burn agriculture and pastoralism predominate, often combined with a nomadic or semi-nomadic lifestyle. Long years of colonialism left an indelible mark on the distribution of the population, methods of farming and the nature of the use of natural resources.

Sharply reflected on the state of the natural environment African countries also have socio-demographic processes in recent decades: high rates of population reproduction, which is associated with the expansion of acreage and pastures, excessive and not always rational use of natural resources, urban growth. All this taken together has led to the fact that at present relatively few areas of Africa have preserved their pristine nature. Changes in the composition of forests under the influence of felling and burning, or even displacement of forests by anthropogenic savanna, desertification of savannas in zones bordering deserts, the spread of introduced plants and animals of other continents and the extermination of local species - all these results of human activity have become widespread not only in the most developed and populated areas. the outskirts of the mainland, but also in its interior regions. In 1990-1995 The rate of deforestation in Africa was 0.7% per year. Over 15 years (from 1980 to 1995), the area of ​​African forests decreased by 66 million hectares. The rate of deforestation is highest in southern West Africa.

Over the past 100 years in Africa there has been a significant worsened state of terrestrial and freshwater ecosystems. Rapid population growth, agricultural intensification, urbanization and industrial growth have increased environmental degradation and depletion of natural resources. Some of the most pressing environmental problems include loss of soil fertility, accelerated erosion processes, deforestation, decline in biodiversity, increasing water scarcity, and deterioration in water and air quality (Fig. 110).