Anthropogenic impact on the environment. Anthropogenic impact on nature

In South America, there are many environmental problems caused by technological progress and economic development. Forests are being destroyed and water bodies are being polluted, biodiversity is being reduced and soil is being depleted, the atmosphere is being polluted and wildlife areas are shrinking. All this can lead to an ecological catastrophe in the future.
In the cities of South American countries, environmental problems of the following nature have formed:

• the problem of unsanitary conditions;
• water pollution;
• the problem of garbage and municipal solid waste disposal;
• air pollution;
• the problem of energy resources, etc.

Deforestation problem

A significant part of the mainland is covered with tropical forests, which are the lungs of the planet. Trees are constantly cut down, not only to sell timber, but also to create farmland and pastures. All this leads to a change in the forest ecosystem, the destruction of some species of flora and the migration of fauna. To save the forest, many countries regulate logging activities at the legislative level. There are entire zones where it is prohibited, forests are being restored and new trees are being planted.

Problems of the hydrosphere

There are many problems in the coastal areas of the seas and oceans:

• overfishing;
• water pollution with garbage, oil products and chemicals;
• housing and communal and industrial effluents.

All these wastes negatively affect the state of water bodies, flora and fauna.

In addition, many rivers flow through the mainland, including the largest river in the world, the Amazon. The rivers of South America are also affected by human activity. In the waters, many species of fish and animals are disappearing. The life of local tribes, who have lived on the banks of rivers for millennia, has also become very complicated, they are forced to look for new habitats. Dams and various structures have led to changes in river regimes and water pollution.

Biosphere pollution

The source of air pollution is greenhouse gases emitted by vehicles and industries:

• mines and deposits;
• enterprises of the chemical industry;
• oil refineries;
• energy facilities;
• metallurgical plants.

Soil pollution contributes to agriculture, which uses pesticides, chemical and mineral fertilizers. The soil is also depleted, which leads to soil degradation. Land resources are being destroyed.

§one. Classification of anthropogenic impacts

Anthropogenic impacts include all environmentally depressing impacts created by technology or directly by man. They can be combined into the following groups:

1) pollution, i.e. the introduction of physical, chemical and other elements uncharacteristic for it into the environment or an artificial increase in the existing natural level of these elements;

2) technical transformations and destruction of natural systems and landscapes in the process of extraction of natural resources, construction, etc.;

3) withdrawal of natural resources - water, air, minerals, fossil fuels, etc.;

4) global climate impacts;

5) violation of the aesthetic value of landscapes, i.e. change in natural forms, unfavorable for visual perception.

One of the most significant negative impacts on nature are pollution, which are subdivided according to type, source, consequences, control measures, etc. Sources of anthropogenic pollution are industrial and agricultural enterprises, energy facilities, and transport. A significant share in the overall balance is made by household pollution.

Anthropogenic pollution can be local, regional and global. They are divided into the following types:

biological,

mechanical,

chemical,

physical,

physical and chemical.

biological, as well as microbiological pollution occurs when biological waste enters the environment or as a result of the rapid multiplication of microorganisms on anthropogenic substrates.

mechanical pollution is associated with substances that do not have physical and chemical effects on organisms and the environment. It is typical for the processes of production of building materials, construction, repair and reconstruction of buildings and structures: it is waste from stone sawing, production of reinforced concrete, bricks, etc. The cement industry, for example, ranks first in air emissions of solid pollutants (dust), followed by sand-lime brick factories, lime factories and porous aggregate factories.

Chemical pollution can be caused by the introduction of some new chemical compounds into the environment or by an increase in the concentrations of substances already present. Many of the chemicals are active and can interact with the molecules of substances inside living organisms or actively oxidize in the air, thus becoming toxic to them. The following groups of chemical contaminants are distinguished:

1) aqueous solutions and sludges with acidic, alkaline and neutral reactions;

2) non-aqueous solutions and sludges (organic solvents, resins, oils, fats);

3) solid pollution (reactive dust);

4) gaseous pollution (vapours, exhaust gases);

5) specific - especially toxic (asbestos, compounds of mercury, arsenic, lead, phenol-containing pollution).

According to the results of international studies, which were carried out under the auspices of the UN, a list of the most important substances polluting the environment was compiled. It included:

§ sulfur trioxide (sulfuric anhydride) SO 3;

§ suspended particles;

§ carbon oxides CO and CO 2

§ nitrogen oxides NOx;

§ photochemical oxidizers (ozone О 3 , hydrogen peroxide Н 2 О 2 , OH - hydroxyl radicals, PAN peroxyacyl nitrates and aldehydes);

§ mercury Hg;

§ lead Pb;

§ cadmium Cd;

§ chlorinated organic compounds;

§ toxins of fungal origin;

§ nitrates, more often in the form of NaNO 3;

§ ammonia NH 3;

§ individual microbial contaminants;

§ radioactive contamination.

According to the ability to persist under external influence, chemical contaminants are divided into:

a) persistent and

b) degradable by chemical or biological processes.

To physical contaminants include:

1) thermal, arising from an increase in temperature due to heat losses in industry, residential buildings, in heating mains, etc.;

2) noise as a result of increased noise from enterprises, transport, etc.;

3) light, arising as a result of unreasonably high illumination created by artificial light sources;

4) electromagnetic from radio, television, industrial installations, power lines;

5) radioactive.

Pollution from various sources enters the atmosphere, water bodies, lithosphere, after which they begin to migrate in different directions. From the habitats of a separate biotic community, they are transmitted to all components of the biocenosis - plants, microorganisms, animals. Directions and forms of pollution migration can be as follows (Table 2):

table 2

Forms of pollution migration between natural environments

Direction of migration

Migration forms

Atmosphere - atmosphere Atmosphere - hydrosphere Atmosphere - land surface Atmosphere - biota Hydrosphere - atmosphere Hydrosphere - hydrosphere Hydrosphere - land surface, bottom of rivers, lakes Hydrosphere - biota Land surface - hydrosphere Land surface - land surface Land surface - atmosphere Land surface - biota Biota - atmosphere Biota - hydrosphere Biota - land surface Biota - biota

Atmospheric transport Deposition (washout) on water surface Deposition (washout) on land surface Deposition on plant surfaces (foliar intake) Evaporation from water (oil products, mercury compounds) Transport in aquatic systems Transfer from water to soil, filtration, self-purification of water, sedimentation pollution Transfer from surface waters to terrestrial and aquatic ecosystems, entry into organisms with drinking water Runoff with precipitation, temporary streams, during snowmelt Migration in soil, glaciers, snow cover Blowing off and transport by air masses Root entry of pollutants into vegetation Evaporation Ingress into water after death organisms Entry into the soil after the death of organisms Migration through food chains

The construction industry is a powerful tool destruction of natural systems and landscapes. The construction of industrial and civil facilities leads to the rejection of large areas of fertile land, a reduction in the living space of all inhabitants of ecosystems, and a serious change in the geological environment. Table 3 illustrates the results of the impact of construction on the geological structure of the territories.

Table 3

Changes in the geological situation at construction sites

Violations of the natural environment are accompanied by the extraction and processing of minerals. This is expressed as follows.

1. The creation of large quarries and embankments leads to the formation of a technogenic landscape, reduction of land resources, deformation of the earth's surface, depletion and destruction of soils.

2. Drainage of deposits, water intake for the technical needs of mining enterprises, discharge of mine and waste waters violate the hydrological regime of the water basin, deplete the reserves of underground and surface waters, and worsen their quality.

3. Drilling, blasting, loading of the rock mass is accompanied by a deterioration in the quality of atmospheric air.

4. The above processes, as well as industrial noise, contribute to the deterioration of living conditions and the reduction in the number and species composition of plants and animals, and the reduction in crop yields.

5. Mining, dewatering of deposits, extraction of minerals, burial of solid and liquid wastes lead to a change in the natural stress-strain state of the rock mass, flooding and flooding of deposits, and pollution of the subsoil.

Now disturbed territories appear and develop in almost every city; territories with a threshold (supercritical) change in any characteristic of engineering-geological conditions. Any such change limits the specific functional use of the area and requires the implementation of reclamation, i.e. a set of works aimed at restoring the biological and economic value of disturbed lands.

One of the main reasons depletion of natural resources is the extravagance of the people. Thus, according to some experts, explored mineral reserves will be completely depleted in 60-70 years. Known oil and gas fields may be exhausted even faster.

At the same time, only 1/3 of the consumed raw materials are directly spent on the production of industrial products, and 2/3 is lost in the form of by-products and waste polluting the environment (Fig. 9).

In the entire history of human society, about 20 billion tons of ferrous metals have been smelted, and in structures, machines, transport, etc. they sold only 6 billion tons. The rest is dispersed in the environment. Currently, more than 25% of the annual production of iron is dissipated, and even more of some other substances. For example, dispersion of mercury and lead reaches 80 - 90% of their annual production.

NATURAL DEPOSITS

Retrieved Leftovers

Losses

Recycling Partial refund

Partial return

Products

Failure, wear, corrosion

Scrap Pollution

Fig.9. Resource cycle diagram

The balance of oxygen on the planet is on the verge of disruption: at the current rate of deforestation, photosynthetic plants will soon be unable to replenish its costs for the needs of industry, transport, energy, etc.

Global climate change caused by human activities are characterized primarily by global temperature rise. Experts believe that in the next decade, the heating of the earth's atmosphere may increase to a dangerous level: in the tropics, the temperature is predicted to rise by 1-2 0 C, and near the poles by 6-8 0 C.

Due to the melting of the polar ice, the level of the World Ocean will rise markedly, which will lead to the flooding of vast populated areas and agricultural areas. Associated mass epidemics are predicted, especially in South America, India, and the Mediterranean countries. The number of oncological diseases will increase everywhere. The power of tropical cyclones, hurricanes, and tornadoes will increase significantly.

The root cause of all this is the greenhouse effect, due to an increase in the concentration in the stratosphere at an altitude of 15-50 km of gases that are usually not present there: carbon dioxide, methane, nitrogen oxides, chlorofluorocarbons. The layer of these gases plays the role of an optical filter, passing the sun's rays and delaying the thermal radiation reflected from the earth's surface. This causes an increase in temperature in the surface space, like under the roof of a greenhouse. And the intensity of this process is growing: over the past 30 years alone, the concentration of carbon dioxide in the air has increased by 8%, and in the period from 2030 to 2070, its content in the atmosphere is expected to double compared to pre-industrial levels.

Thus, the global increase in temperature in the coming decades and the adverse events associated with it are beyond doubt. At the current level of development of civilization, it is only possible to slow down this process in one way or another. Thus, every possible saving of fuel and energy resources directly contributes to slowing down the rate of atmospheric heating. Further steps in this direction are the transition to resource-saving technologies and devices, to new construction projects.

Significant warming has already been delayed by 20 years, by some estimates, due to the almost complete cessation of the production and use of chlorofluorocarbons in industrialized countries.

At the same time, there are a number of natural factors hindering climate warming on Earth, for example, stratospheric aerosol layer, formed by volcanic eruptions. It is located at an altitude of 20-25 km and consists mainly of sulfuric acid droplets with an average size of 0.3 microns. It also contains particles of salts, metals, and other substances.

The particles of the aerosol layer reflect solar radiation back into space, which leads to some decrease in temperature in the surface layer. Despite the fact that particles in the stratosphere are about 100 times smaller than in the lower layer of the atmosphere - the troposphere - they have a more noticeable climatic effect. This is due to the fact that stratospheric aerosol mainly lowers the air temperature, while tropospheric aerosol can both lower and increase it. In addition, each particle in the stratosphere exists for a long time - up to 2 years, while the lifetime of tropospheric particles does not exceed 10 days: they are quickly washed out by rains and fall to the ground.

Violation of the aesthetic value of landscapes It is typical for construction processes: the construction of buildings and structures that are not large-scale natural formations makes a negative impression, worsens the historically established view of landscapes.

All technogenic impacts lead to a deterioration in the quality indicators of the environment, which are characterized by conservatism, since they were developed over millions of years of evolution.

To assess the activity of anthropogenic impact on the nature of the Kirov region for each area, an integral anthropogenic load was established, obtained on the basis of assessments of the impact on the environment of three types of pollution sources:

§ local (household and industrial waste);

§ territorial (agriculture and forest exploitation);

§ local-territorial (transport).

It has been established that the areas with the highest environmental stress include: the city of Kirov, the district and the city of Kirovo-Chepetsk, the district and the city of Vyatskiye Polyany, the district and the city of Kotelnich, the district and the city of Slobodskoy.

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1. The zone of equatorial forests occupies in South America giant areas of the Amazonian lowland, the adjacent foothills of the Eastern Andes, the northern part of the Pacific coast in the region of the equatorial climatic zone. These forests are called selvas, which means “forests” in Portuguese. A. Humboldt suggested calling them hylaea (from the Greek. "Gileion" - forest).

2. Zones of savannas, light forests and shrubs are located mainly in the subequatorial and partly in the tropical climatic zones. The savannahs occupy the Orinoc lowland, where they are called llanos, as well as the hinterland of the Guiana and Brazilian highlands (campos).

3. The zone of subtropical steppes, which are called pampas here, is located south of the savannas of the tropical belt. The soils in the pampa are reddish-black, formed as a result of the decay of dense vegetation from turf grasses - pampas grass, feather grass, bluegrass, etc. These soils have a significant humus horizon (up to 40 cm) and are very fertile. For the natural areas of the pampas, fast running animals are typical - pampas deer, pampas cat, llamas. There are many rodents along the banks of rivers and lakes - nutria, viscacha. At present, the natural landscapes in the pampas are little preserved: convenient lands are plowed up (fields of wheat, corn), dry steppes are divided into huge pens for cattle.

4. The zone of semi-deserts of the temperate belt prevails on the territory of the southern - narrowed part of the mainland, in Patagonia. Patagonia is located in the "rain shadow" of the Andes. In the conditions of dry continental climate, on serozems and gray-brown soils (saline in some places), open vegetation cover is common. It is formed by densely sod grasses (bluegrass, feather grass, fescue) and shrubs that form prickly pillows (undersized cacti, ephedra, verbena). Among the endemic representatives of the animal world of Patagonia, it should be noted skunk, Magellanic dog (similar to a fox), Darwin's ostrich (southern species of rhea). There are pampas cat and armadillos, small rodents (tuco-tuco, mara, etc.).

5. The Andes are characterized by altitudinal zonality of landscapes. Sections of the Andes, lying at different latitudes, differ in the number and composition of altitudinal belts. The most complete range of altitudinal belts is presented in the equatorial region.

6. Zone of deciduous and coniferous forests (this is in southern Chile)

Along the Pacific coast, there is a special change in meridional natural zones: in tropical latitudes, a zone of deserts and semi-deserts of the tropical belt is formed (in the Atacama, a loma formation is formed, which is characterized by bulbous and tuberous ephemeroids); in the subtropical zone between 32-38 ° S. sh. there is a zone of dry hard-leaved Mediterranean forests and shrubs. South of 38°S sh. in the subtropical zone - a zone of constantly moist evergreen forests (hemigile zone), which extends to the south and within the temperate zone up to 46 ° S. sh. Hemihylaea consist of evergreen southern beeches, Chilean araucaria, “Chilean cypresses” and other tree species.

"Brazil" - Sloth - also a resident of Brazil. From Liverpool harbour, always on Thursdays, Ships sail to the distant begers. The armadillo lives in burrows. And in case of danger, the armadillo can curl up into a ball like a hedgehog. They speak Portuguese in Brazil. The sloth has long and thin paws with 3 toes with very long claws.

"Natural areas of South America" ​​- Relief. Changing the nature of the mainland under the influence of man. Probably you have already guessed. That's right, the unique nature of South America On the verge of gradual destruction. Why do we say so. Hundreds of species are listed in the Red Book. Soils. Climate. Crocodile living in South America. 11, Rubber tree. 12.

"Lessons South America" ​​- Useful links on the Internet. Lesson objectives: Development of methods of algorithmic and logical thinking. Natural wealth (announcer, text, map, video). Multimedia textbook. Contents Handbook Tests Practice Online. The content of the multimedia textbook. Fauna of South America -10 min. Lesson conclusions.

"Geography Grade 7 South America" ​​- Table. Lesson progress: South America. GP South America. Common features and differences in GP. Lesson topic. Introductory remarks by the teacher…………. SOUTH AMERICA Grade 7. Working with a table. explorers and travelers.

"Mainland South America" ​​- Oil is produced on the shores of Lake Maracaibo. 11. Task 3: "Do you believe - do not believe?". Put a "+" sign if true, and "-" if the statement is not true. General lesson

human impact on nature

1. Settlement of mankind on the territory of the Earth

2. Anthropogenic impact on the nature of Africa

3. Anthropogenic impact on the nature of Eurasia

4. Anthropogenic impact on the nature of North America

5. Anthropogenic impact on the nature of South America

6. Anthropogenic impact on the nature of Australia and Oceania

* * *

1. THE SETTLEMENT OF HUMANITY ON EARTH

Africa is considered the most likely ancestral home modern man.

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

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

Many anthropologists consider Australopithecus as a stage of human evolution, preceding the appearance of the most ancient people. However, the discovery by R. Leakey in 1960 of the Olduvai locality made significant changes to the solution of this problem. In the natural section of the Olduvai Gorge, located in the southeast of the Serengeti Plateau, near the famous Ngorongoro Crater (northern Tanzania), remains of primates close to Australopithecus were found in the thickness of volcanic rocks of Villafranchian age. They got the name Zinjanthropes. Below and above the Zinjanthropes, the skeletal remains of a prezinjanthropus, or Homo habilis (Handy Man), were found. Together with the presinjanthropus, primitive stone products were found - roughly upholstered pebbles. In the overlying layers of the Olduvai locality, the remains of African archanthropes, and on the same level with them - Australopithecus. The mutual position of the remains of prezinjanthropus and zinjantrops (australopithecus) suggests that the australopithecines, previously considered the direct ancestors of the most ancient people, actually formed a non-progressive branch of hominids that existed for a long time between Villafranchian and the middle Pleistocene. This thread is over dead end.

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Anthropogenic impact on nature

environmental atmosphere pollutant

Introduction

5. Radiation in the biosphere

Conclusion

Introduction

Man has always used the environment mainly as a source of resources, but for a very long time his activity did not have a noticeable impact on the biosphere. Only at the end of the last century, changes in the biosphere under the influence of economic activity attracted the attention of scientists. In the first half of the 20th century, these changes were growing and at present they have fallen like an avalanche on human civilization. In an effort to improve the conditions of his life, a person constantly increases the pace of material production, without thinking about the consequences. With this approach, most of the resources taken from nature are returned to it in the form of waste, often poisonous or unsuitable for disposal. This poses a threat to the existence of the biosphere, and of man himself.

Mankind in the process of life, of course, affects various ecological systems. Examples of such, most often dangerous, impacts are the drainage of swamps, deforestation, the destruction of the ozone layer, the diversion of the flow of rivers, and the discharge of waste into the environment. In this way, a person destroys the existing ties in a stable system, which can lead to its destabilization, that is, to an ecological catastrophe.

Currently, the entire territory of our planet is subject to various anthropogenic influences.

Anthropogenic impact on nature - various forms of influence of human activity on nature. Its impact covers individual components of nature and natural complexes. Anthropogenic impacts can be both positive and negative; the latter necessitates the application of special environmental measures.

1. Current state of the natural environment

With the advent and development of mankind, the process of evolution has noticeably changed. In the early stages of civilization, cutting down and burning forests for agriculture, grazing, fishing and hunting for wild animals, wars devastated entire regions, led to the destruction of plant communities, and the extermination of certain animal species. As civilization developed, especially the end of the Middle Ages, which was turbulent after the industrial revolution, mankind seized more and more power, an ever greater ability to involve and use huge masses of matter to satisfy its growing needs - both organic, living, and mineral, inert.

Population growth and the expanding development of agriculture, industry, construction, and transport caused massive deforestation in Europe and North America. Livestock grazing on a large scale led to the death of forests and grass cover, to the erosion of the soil layer (Central Asia, North Africa, southern Europe and the USA). Exterminated dozens of animal species in Europe, America, Africa.

Scientists suggest that soil depletion in the territory of the ancient Central American Mayan state as a result of slash-and-burn agriculture was one of the reasons for the death of this highly developed civilization. Similarly, in ancient Greece, vast forests disappeared as a result of deforestation and immoderate grazing. This increased soil erosion and led to the destruction of the soil cover on many mountain slopes, increased the aridity of the climate and worsened agricultural conditions.

Construction and operation of industrial enterprises, mining have led to serious violations of natural landscapes, pollution of soil, water, air with various wastes.

Real shifts in biospheric processes began in the 20th century. as a result of the next industrial revolution. The rapid development of energy, mechanical engineering, chemistry, and transport has led to the fact that human activity has become comparable in scale with the natural energy and material processes occurring in the biosphere. The intensity of human consumption of energy and material resources is growing in proportion to the population and even ahead of its growth.

As a result of the combustion of various fuels, about 20 billion tons of carbon dioxide are released into the atmosphere annually and a corresponding amount of oxygen is absorbed. The natural supply of CO2 in the atmosphere is about 50,000 billion tons. This value fluctuates and depends, in particular, on volcanic activity. However, anthropogenic emissions of carbon dioxide exceed natural ones and currently account for a large proportion of its total amount. An increase in the concentration of carbon dioxide in the atmosphere, accompanied by an increase in the amount of aerosol, can lead to noticeable climate changes and, accordingly, to disruption of the equilibrium relationships that have developed over millions of years in the biosphere.

The result of the violation of the transparency of the atmosphere, and hence the heat balance, may be the emergence of a "greenhouse effect", that is, an increase in the average temperature of the atmosphere by several degrees. This can cause the melting of glaciers in the polar regions, an increase in the level of the World Ocean, a change in its salinity, temperature, global climate disturbances, flooding of coastal lowlands, and many other adverse consequences.

The release of industrial gases into the atmosphere, including compounds such as carbon monoxide, nitrogen oxides, sulfur, ammonia and other pollutants, leads to the inhibition of the vital activity of plants and animals, metabolic disorders, poisoning and death of living organisms.

Uncontrolled influence on the climate in combination with irrational agriculture can lead to a significant decrease in soil fertility, large fluctuations in crop yields. According to UN experts, in recent years, fluctuations in agricultural production have exceeded 1%. But a decrease in food production even by 1% can lead to the death of tens of millions of people from starvation.

The forests on our planet are catastrophically reduced. Irrational deforestation and fires have led to the fact that in many places, once completely covered with forests, by now they have survived only on 10-30% of the territory. The area of ​​tropical forests in Africa has decreased by 70%, in South America - by 60%, in China only 8% of the territory is covered with forest.

At present, the total power of anthropogenic pollution sources in many cases exceeds the power of natural ones. Thus, natural sources of nitric oxide emit 30 million tons of nitrogen per year, and anthropogenic - 35-50 million tons; sulfur dioxide, respectively, about 30 million tons and more than 150 million tons. As a result of human activity, lead enters the biosphere almost 10 times more than in the process of natural pollution.

Pollutants resulting from human activities and their impact on the environment are very diverse. These include: compounds of carbon, sulfur, nitrogen, heavy metals, various organic substances, artificially created materials, radioactive elements and much more.

Thus, according to experts, about 10 million tons of oil enter the ocean every year. Oil on water forms a thin film that prevents gas exchange between water and air. Settling to the bottom, oil enters bottom sediments, where it disrupts the natural life processes of bottom animals and microorganisms. In addition to oil, there has been a significant increase in the release of domestic and industrial wastewater into the ocean, containing, in particular, such dangerous pollutants as lead, mercury, and arsenic, which have a strong toxic effect. Background concentrations of such substances in many places have already been exceeded by dozens of times.

Each pollutant has a certain negative impact on nature, so their entry into the environment must be strictly controlled. The legislation establishes for each pollutant the maximum allowable discharge (MPD) and the maximum allowable concentration (MPC) of it in the natural environment.

Maximum allowable discharge (MPD) is the mass of a pollutant emitted by individual sources per unit of time, the excess of which leads to adverse effects in the environment or is dangerous to human health.

The maximum allowable concentration (MAC) is understood as the amount of a harmful substance in the environment that does not adversely affect human health or its offspring through permanent or temporary contact with it. Currently, when determining MPC, not only the degree of influence of pollutants on human health is taken into account, but also their impact on animals, plants, fungi, microorganisms, as well as on the natural community as a whole.

Special environmental monitoring (surveillance) services monitor compliance with the established standards for MPC and MPC of harmful substances. Such services have been established in all regions of the country. Their role is especially important in large cities, near chemical plants, nuclear power plants and other industrial facilities. Monitoring services have the right to apply measures provided by law, up to the suspension of production and any work, if environmental protection standards are violated.

In addition to environmental pollution, anthropogenic impact is expressed in the depletion of the natural resources of the biosphere. The enormous use of natural resources has led to a significant change in landscapes in some regions (for example, in the coal basins). If at the dawn of civilization man used only about 20 chemical elements for his needs, at the beginning of the 20th century. about 60, now more than 100 - almost the entire periodic table. About 100 billion tons of ore, fuel, and mineral fertilizers are annually mined (extracted from the geosphere).

The rapid growth in demand for fuel, metals, minerals and their extraction led to the depletion of these resources. Thus, according to experts, while maintaining current rates of production and consumption, the explored reserves of oil will be exhausted in 30 years, gas - in 50 years, coal - in 200. A similar situation has developed not only with energy resources, but also with metals (depletion of reserves aluminum is expected in 500-600 years, iron - 250 years, zinc - 25 years, lead - 20 years) and mineral resources such as asbestos, mica, graphite, sulfur.

This is a far from complete picture of the ecological situation on our planet at the present time. Even individual successes in environmental protection activities cannot noticeably change the general course of the process of the harmful influence of civilization on the state of the biosphere.

2. Atmosphere - the outer shell of the biosphere. Air pollution

The mass of the atmosphere of our planet is negligible - only one millionth of the mass of the Earth. However, its role in the natural processes of the biosphere is enormous. The presence of the atmosphere around the globe determines the general thermal regime of the surface of our planet, protects it from harmful cosmic and ultraviolet radiation. Atmospheric circulation has an impact on local climatic conditions, and through them - on the regime of rivers, soil and vegetation cover and the processes of relief formation.

The modern gas composition of the atmosphere is the result of a long historical development of the globe. It is mainly a gas mixture of two components - nitrogen (78.09%) and oxygen (20.95%). Normally, it also contains argon (0.93%), carbon dioxide (0.03%) and small amounts of inert gases (neon, helium, krypton, xenon), ammonia, methane, ozone, sulfur dioxide and other gases. Along with gases, the atmosphere contains solid particles coming from the Earth's surface (for example, products of combustion, volcanic activity, soil particles) and from space (cosmic dust), as well as various products of plant, animal or microbial origin. In addition, water vapor plays an important role in the atmosphere.

The three gases that make up the atmosphere are of greatest importance for various ecosystems: oxygen, carbon dioxide and nitrogen. These gases are involved in the main biogeochemical cycles.

Oxygen plays an essential role in the life of most living organisms on our planet. It is necessary for everyone to breathe.

Oxygen has not always been part of the earth's atmosphere. It appeared as a result of the vital activity of photosynthetic organisms. Under the influence of ultraviolet rays, it turns into ozone. As ozone accumulated, an ozone layer formed in the upper atmosphere. The ozone layer, like a screen, reliably protects the Earth's surface from ultraviolet radiation, which is fatal to living organisms. The modern atmosphere contains hardly a twentieth of the oxygen available on our planet. The main reserves of oxygen are concentrated in carbonates, in organic substances and iron oxides, part of the oxygen is dissolved in water. In the atmosphere, apparently, there was an approximate balance between the production of oxygen in the process of photosynthesis and its consumption by living organisms. But recently there has been a danger that, as a result of human activity, oxygen reserves in the atmosphere may decrease. Of particular danger is the destruction of the ozone layer, which has been observed in recent years. Most scientists attribute this to human activity.

The oxygen cycle in the biosphere is extremely complex, since a large number of organic and inorganic substances, as well as hydrogen, react with it, combining with which oxygen forms water.

· Carbon dioxide (carbon dioxide) is used in the process of photosynthesis to form organic substances.

It is thanks to this process that the carbon cycle in the biosphere closes. Like oxygen, carbon is a part of soils, plants, animals, and participates in various mechanisms of the circulation of substances in nature. The content of carbon dioxide in the air we breathe is about the same in different parts of the world. The exception is large cities in which the content of this gas in the air is above the norm.

Some fluctuations in the content of carbon dioxide in the air of the area depend on the time of day, the season of the year, and the biomass of vegetation. At the same time, studies show that since the beginning of the century, the average content of carbon dioxide in the atmosphere, although slowly, but constantly increases.

Nitrogen is an indispensable biogenic element, since it is part of proteins and nucleic acids.

The atmosphere is an inexhaustible reservoir of nitrogen, but the majority of living organisms cannot directly use this nitrogen: it must first be bound in the form of chemical compounds.

Part of the nitrogen comes from the atmosphere to ecosystems in the form of nitric oxide, which is formed under the action of electrical discharges during thunderstorms. However, the main part of nitrogen enters the water and soil as a result of its biological fixation. There are several types of bacteria and blue-green algae (fortunately, very numerous) that are able to fix atmospheric nitrogen. As a result of their activities, as well as due to the decomposition of organic residues in the soil, autotrophic plants are able to absorb the necessary nitrogen.

The nitrogen cycle is closely related to the carbon cycle. Although the nitrogen cycle is more complex than the carbon cycle, it tends to be faster.

Other constituents of the air do not participate in biochemical cycles, but the presence of a large amount of pollutants in the atmosphere can lead to serious violations of these cycles.

Various negative changes in the Earth's atmosphere are mainly associated with changes in the concentration of minor components of atmospheric air.

There are two main sources of air pollution: natural and anthropogenic.

· The natural source is volcanoes, dust storms, weathering, forest fires, processes of decomposition of plants and animals.

· The main anthropogenic sources of air pollution include enterprises of the fuel and energy complex, transport, and various machine-building enterprises.

According to scientists, every year in the world as a result of human activity, 25.5 billion tons of carbon oxides, 190 million tons of sulfur oxides, 65 million tons of nitrogen oxides, 1.4 million tons of chlorofluorocarbons (freons ), organic lead compounds, hydrocarbons, including carcinogenic ones.

In addition to gaseous pollutants, a large amount of particulate matter enters the atmosphere. These are dust, soot and soot. Contamination of the natural environment with heavy metals poses a great danger. Lead, cadmium, mercury, copper, nickel, zinc, chromium, vanadium have become almost constant components of the air in industrial centers. The problem of air pollution with lead is particularly acute.

Global air pollution affects the state of natural ecosystems, especially the green cover of our planet. Forests are one of the most obvious indicators of the state of the biosphere.

Acid rains, caused mainly by sulfur dioxide and nitrogen oxides, cause great harm to forest biocenoses. It has been established that conifers suffer from acid rain to a greater extent than broad-leaved ones.

Only on the territory of our country the total area of ​​forests affected by industrial emissions has reached 1 million hectares. A significant factor in forest degradation in recent years is environmental pollution with radionuclides. Thus, as a result of the accident at the Chernobyl nuclear power plant, 2.1 million hectares of forests were affected.

Particularly affected are green spaces in industrial cities, the atmosphere of which contains a large amount of pollutants.

The air environmental problem of ozone depletion, including the appearance of ozone holes over Antarctica and the Arctic, is associated with the excessive use of freons in production and everyday life.

3. Soil is an important part of the biosphere. Soil pollution

Soil - the top layer of land, formed under the influence of plants, animals, microorganisms and climate from the parent rocks on which it is located. This is an important and complex component of the biosphere, closely related to its other parts.

The following main components interact in a complex way in the soil:

mineral particles (sand, clay), water, air;

detritus - dead organic matter, the remains of vital activity of plants and animals;

· many living organisms - from detritus feeders to decomposers, decomposing detritus to humus.

Thus, the soil is a bioinert system based on the dynamic interaction between mineral components, detritus, detritus feeders and soil organisms.

Soils go through several stages in their development and formation.

Young soils are usually the result of weathering of parent rocks or the transport of sedimentary deposits (eg alluvium). Microorganisms, pioneer plants - lichens, mosses, grasses, small animals settle on these substrates. Gradually, other species of plants and animals are introduced, the composition of the biocenosis becomes more complicated, a whole series of relationships arise between the mineral substrate and living organisms. As a result, a mature soil is formed, the properties of which depend on the original parent rock and climate.

The process of soil development ends when equilibrium is reached, the correspondence of the soil with the vegetation cover and climate, that is, a climax state occurs. Thus, the changes in the soil that occur during its formation resemble the successional changes in ecosystems.

Each type of soil corresponds to certain types of plant communities. Thus, pine forests, as a rule, grow on light sandy soils, while spruce forests prefer heavier and nutrient-rich loamy soils.

The soil is like a living organism, within which various complex processes take place. In order to maintain the soil in good condition, it is necessary to know the nature of the metabolic processes of all its constituents.

The surface layers of the soil usually contain many remains of plant and animal organisms, the decomposition of which leads to the formation of humus. The amount of humus determines the fertility of the soil.

A great many different living organisms live in the soil - edaphobionts, which form a complex food detritus network: bacteria, microfungi, algae, protozoa, mollusks, arthropods and their larvae, earthworms and many others. All these organisms play a huge role in the formation of the soil and changing its physical and chemical characteristics.

Plants absorb the necessary minerals from the soil, but after the death of plant organisms, the removed elements return to the soil. Soil organisms gradually process all organic residues. Thus, under natural conditions, there is a constant circulation of substances in the soil.

In artificial agrocenoses, such a cycle is disrupted, since a person withdraws a significant part of agricultural products, using it for their own needs. Due to the non-participation of this part of the production in the cycle, the soil becomes barren. To avoid this and increase soil fertility in artificial agrocenoses, a person makes organic and mineral fertilizers.

Under normal natural conditions, all processes occurring in the soil are in balance. But often a person is to blame for the violation of the equilibrium state of the soil. As a result of the development of human activities, pollution, changes in the composition of the soil and even its destruction occur. Currently, there is less than one hectare of arable land for every inhabitant of our planet. And these insignificant areas continue to shrink due to inept human activities.

Enormous areas of fertile lands are lost during mining operations, during the construction of enterprises and cities. The destruction of forests and natural grass cover, repeated plowing of the land without observing the rules of agricultural technology leads to soil erosion - the destruction and washing away of the fertile layer by water and wind. Erosion has now become a worldwide evil. It is estimated that in the last century alone, as a result of water and wind erosion, 2 billion hectares of fertile lands of active agricultural use have been lost on the planet.

One of the consequences of increased human production activity is the intense pollution of the soil cover. The main soil pollutants are metals and their compounds, radioactive elements, as well as fertilizers and pesticides used in agriculture.

Mercury and its compounds are among the most dangerous soil pollutants. Mercury enters the environment with pesticides, industrial waste containing metallic mercury and its various compounds.

Lead pollution of soils is even more widespread and dangerous. It is known that during the smelting of one ton of lead, up to 25 kg of lead is released into the environment with waste. Lead compounds are used as additives to gasoline, so motor vehicles are a serious source of lead pollution. Especially a lot of lead in soils along major highways.

Near large centers of ferrous and non-ferrous metallurgy, soils are contaminated with iron, copper, zinc, manganese, nickel, aluminum and other metals. In many places, their concentration is tens of times higher than the MPC.

Radioactive elements can get into the soil and accumulate in it as a result of precipitation from atomic explosions or during the removal of liquid and solid waste from industrial enterprises, nuclear power plants or research institutions associated with the study and use of atomic energy. Radioactive substances from soils get into plants, then into the organisms of animals and humans, accumulate in them.

Modern agriculture, which widely uses fertilizers and various chemicals to control pests, weeds and plant diseases, has a significant impact on the chemical composition of soils. At present, the amount of substances involved in the cycle in the process of agricultural activity is approximately the same as in the process of industrial production. At the same time, the production and use of fertilizers and pesticides in agriculture is increasing every year. Inept and uncontrolled use of them leads to disruption of the circulation of substances in the biosphere.

Of particular danger are persistent organic compounds used as pesticides. They accumulate in the soil, in water, bottom sediments of reservoirs. But most importantly, they are included in ecological food chains, pass from soil and water to plants, then to animals, and ultimately enter the human body with food.

4. Water is the basis of life processes in the biosphere. Pollution of natural waters

Water is the most common inorganic compound on our planet. Water is the basis of all life processes, the only source of oxygen in the main driving process on Earth - photosynthesis. Water is present throughout the biosphere: not only in water bodies, but also in the air, and in the soil, and in all living beings. The latter contain up to 80-90% water in their biomass. Losses of 10-20% of water by living organisms lead to their death.

In its natural state, water is never free from impurities. Various gases and salts are dissolved in it, there are suspended solid particles. 1 liter of fresh water can contain up to 1 g of salts.

Most of the water is concentrated in the seas and oceans. Fresh water accounts for only 2%. Most of the fresh water (85%) is concentrated in the ice of the polar zones and glaciers. Renewal of fresh water occurs as a result of the water cycle.

With the advent of life on Earth, the water cycle became relatively complex, since more complex processes associated with the vital activity of living organisms were added to the simple phenomenon of physical evaporation (turning water into steam). In addition, the role of man, as he develops, becomes more and more significant in this cycle.

The water cycle in the biosphere occurs as follows:

Water falls to the Earth's surface as precipitation from atmospheric water vapor.

§ A certain part of the precipitation evaporates directly from the surface, returning to the atmosphere as water vapor.

§ The other part penetrates the soil, is absorbed by the roots of plants and then, after passing through the plants, evaporates in the process of transpiration.

§ The third part seeps into the deep layers of the subsoil to impervious horizons, replenishing groundwater.

§ The fourth part in the form of surface, river and underground runoff flows into water bodies, from where it also evaporates into the atmosphere.

§ Finally, a part is used by animals and consumed by man for his needs.

All the water evaporated and returned to the atmosphere condenses and falls again as precipitation.

Thus, one of the main ways of the water cycle - transpiration, that is, biological evaporation, is carried out by plants, supporting their vital activity. The amount of water released as a result of transpiration depends on the plant species, the type of plant communities, their biomass, climatic factors, seasons, and other conditions.

The intensity of transpiration and the mass of water evaporating in this case can reach very significant values. In communities such as forests (with a large phytomass and leaf surface) or swamps (with a water-saturated moss surface), transpiration is generally quite comparable with the evaporation of open water bodies (ocean) and often even exceeds it.

The value of total evaporation (from the soil, from the surface of plants and through transpiration) depends on the physiological characteristics of plants and their biomass, therefore it serves as an indirect indicator of the vital activity and productivity of communities.

Pollution of water bodies is understood as a decrease in their biospheric functions and economic significance as a result of the entry of harmful substances into them.

One of the main water pollutants is oil and oil products. Oil can get into the water as a result of its natural outflows in the areas of occurrence. But the main sources of pollution are associated with human activities: oil production, transportation, processing and use of oil as fuel and industrial raw materials.

Among industrial products, toxic synthetic substances occupy a special place in terms of their negative impact on the aquatic environment and living organisms. They are increasingly being used in industry, in transport, and in public utilities. The concentration of these compounds in wastewater, as a rule, is 5-15 mg/l at MPC - 0.1 mg/l. These substances can form a layer of foam in reservoirs, which is especially noticeable on rapids, rifts, locks. The ability to foam in these substances appears already at a concentration of 1-2 mg / l.

Other contaminants include metals (eg mercury, lead, zinc, copper, chromium, tin, manganese), radioactive elements, pesticides from agricultural fields, and runoff from livestock farms.

Expanded production (without treatment facilities) and the use of pesticides in the fields lead to severe pollution of water bodies with harmful compounds. Pollution of the aquatic environment occurs as a result of the direct introduction of pesticides during the treatment of water bodies for pest control, the ingress of water flowing down from the surface of cultivated agricultural land into water bodies, when waste from manufacturing enterprises is discharged into water bodies, as well as as a result of losses during transportation, storage and partially with atmospheric precipitation.

Along with pesticides, agricultural effluents contain a significant amount of fertilizer residues (nitrogen, phosphorus, potassium) applied to the fields. In addition, large amounts of organic compounds of nitrogen and phosphorus enter with runoff from livestock farms, as well as with sewage. An increase in the concentration of nutrients in the soil leads to a violation of the biological balance in the reservoir.

Initially, in such a reservoir, the number of microscopic algae sharply increases. With an increase in the food supply, the number of crustaceans, fish and other aquatic organisms increases. Then there is the death of a huge number of organisms. It leads to the consumption of all the reserves of oxygen contained in the water, and the accumulation of hydrogen sulfide. The situation in the reservoir changes so much that it becomes unsuitable for the existence of any forms of organisms. The reservoir gradually "dies".

One of the types of water pollution is thermal pollution. Power plants, industrial enterprises often discharge heated water into a reservoir. This leads to an increase in the temperature of the water in it. With an increase in temperature in the reservoir, the amount of oxygen decreases, the toxicity of impurities polluting the water increases, and the biological balance is disturbed.

In polluted water, as the temperature rises, pathogenic microorganisms and viruses begin to multiply rapidly. Once in drinking water, they can cause outbreaks of various diseases.

In a number of regions, groundwater was an important source of fresh water. Previously, they were considered the purest. But at present, as a result of human activities, many sources of groundwater are also being polluted. Often this pollution is so great that the water from them has become undrinkable.

Mankind consumes a huge amount of fresh water for its needs. Its main consumers are industry and agriculture. The most water-intensive industries are mining, steel, chemicals, petrochemicals, pulp and paper, and food. They take up to 70% of all water used in industry. The main consumer of fresh water is agriculture: 60-80% of all fresh water is used for its needs.

In modern conditions, human needs for water for household needs are greatly increasing. The volume of water consumed for these purposes depends on the region and standard of living, ranged from 3 to 700 liters per person. In Moscow, for example, about 650 liters per inhabitant, which is one of the highest rates in the world.

From the analysis of water use over the past 5-6 decades, it follows that the annual increase in irretrievable water consumption, in which the used water is irretrievably lost to nature, is 4-5%. Forward-looking calculations show that if such consumption rates are maintained and taking into account population growth and production volumes, by 2100 mankind can exhaust all fresh water reserves.

Already at the present time, not only the territories that nature has deprived of water resources are experiencing a lack of fresh water, but also many regions that until recently were considered prosperous in this regard. Currently, the need for fresh water is not met by 20% of the urban and 75% of the rural population of the planet.

Human intervention in natural processes has affected even large rivers (such as the Volga, Don, Dnieper), changing downward the volume of transported water masses (river runoff). Most of the water used in agriculture is used for evaporation and the formation of plant biomass and therefore is not returned to the rivers. Already now, in the most populated areas of the country, the flow of rivers has decreased by 8%, and in such rivers as the Don, Terek, Ural - by 11-20%. The fate of the Aral Sea is very dramatic, which, in fact, ceased to exist due to the excessive intake of the waters of the Syrdarya and Amudarya rivers for irrigation.

Limited fresh water supplies are further reduced due to pollution. Wastewater (industrial, agricultural and domestic) poses the main hazard, since a significant part of the used water is returned to water basins in the form of wastewater.

5. Radiation in the biosphere

Radiation pollution have a significant difference from others. Radioactive nuclides are the nuclei of unstable chemical elements that emit charged particles and short-wave electromagnetic radiation. It is these particles and radiation that, when entering the human body, destroy cells, as a result of which various diseases can occur, including radiation.

There are natural sources of radioactivity everywhere in the biosphere, and man, like all living organisms, has always been exposed to natural radiation. External exposure occurs due to radiation of cosmic origin and radioactive nuclides in the environment. Internal exposure is created by radioactive elements that enter the human body with air, water and food.

To quantify the impact of radiation on a person, units are used - the biological equivalent of a roentgen (rem) or sievert (Sv): 1 Sv \u003d 100 rem. Since radioactive radiation can cause serious changes in the body, each person must know its permissible doses.

As a result of internal and external exposure, a person receives an average dose of 0.1 rem during the year and, consequently, about 7 rem throughout his life. In these doses, radiation does not harm a person. However, there are areas where the annual dose is above average. So, for example, people living in high-mountainous regions, due to cosmic radiation, can receive a dose several times greater. Large doses of radiation can be in areas where the content of natural radioactive sources is high. So, for example, in Brazil (200 km from Sao Paulo) there is a hill where the annual dose is 25 rem. This area is uninhabited.

The greatest danger is the radioactive contamination of the biosphere as a result of human activities. At present, radioactive elements are widely used in various fields. Negligence in the storage and transportation of these elements leads to serious radioactive contamination. Radioactive contamination of the biosphere is also associated with the testing of atomic weapons.

In the second half of our century, nuclear power plants, icebreakers, and submarines with nuclear power plants began to be put into operation. During the normal operation of nuclear power facilities and industry, environmental pollution with radioactive nuclides is a negligible fraction of the natural background. A different situation develops in case of accidents at nuclear facilities.

Thus, during the explosion at the Chernobyl nuclear power plant, only about 5% of nuclear fuel was released into the environment. But this led to the exposure of many people, large areas were so polluted that they became hazardous to health. This required the relocation of thousands of residents from the contaminated areas. An increase in radiation as a result of radioactive fallout was noted hundreds and thousands of kilometers from the accident site.

At present, the problem of warehousing and storage of radioactive waste from the military industry and nuclear power plants is becoming more and more acute. Every year they pose an increasing danger to the environment. Thus, the use of nuclear energy has posed new serious problems for mankind.

6. Ecological problems of the biosphere

Human economic activity, acquiring an increasingly global character, begins to have a very tangible impact on the processes taking place in the biosphere. Fortunately, up to a certain level, the biosphere is capable of self-regulation, which makes it possible to minimize the negative consequences of human activity. But there is a limit when the biosphere is no longer able to maintain balance. Irreversible processes begin, leading to ecological disasters. Humanity has already encountered them in a number of regions of the planet.

Mankind has significantly changed the course of a number of processes in the biosphere, including the biochemical cycle and migration of a number of elements. Currently, although slowly, a qualitative and quantitative restructuring of the entire biosphere of the planet is taking place. A number of the most complex ecological problems of the biosphere have already arisen, which must be resolved in the near future.

"The greenhouse effect". The earth is growing at an alarming rate. Over the next 20-25 years, it will increase by 0.2-0.4 degrees, and by 2050 - by 2.5 degrees. Scientists attribute this increase in temperature primarily to an increase in the content of carbon dioxide (carbon dioxide) and aerosols in the atmosphere. This leads to excessive absorption of the Earth's thermal radiation by the air. A certain role in creating the "greenhouse effect" is played by the heat released from thermal power plants and nuclear power plants.

Climate warming can lead to intense melting of glaciers and rising sea levels. The changes that may result from this are simply difficult to predict.

This problem could be solved by reducing carbon dioxide emissions into the atmosphere and establishing a balance in the carbon cycle.

Depletion of the ozone layer. In recent years, scientists have noted with increasing alarm the depletion of the ozone layer of the atmosphere, which is a protective screen against ultraviolet radiation. This process occurs especially quickly over the poles of the planet, where the so-called ozone holes have appeared. The danger lies in the fact that ultraviolet radiation is detrimental to living organisms.

The main reason for the depletion of the ozone layer is the use by people of chlorofluorocarbons (freons), which are widely used in production and everyday life as refrigerants, foaming agents, solvents, and aerosols. Freons intensively destroy ozone. They themselves are destroyed very slowly, within 50-200 years. In 1990 more than 1300 thousand tons of ozone-depleting substances were produced in the world.

Under the action of ultraviolet radiation, oxygen molecules (O 2) decompose into free atoms, which in turn can join other oxygen molecules to form ozone (O 3). Free oxygen atoms can also react with ozone molecules to form two oxygen molecules. Thus, an equilibrium is established and maintained between oxygen and ozone.

However, freon-type pollutants catalyze (accelerate) the process of ozone decomposition, breaking the balance between it and oxygen in the direction of reducing the ozone concentration.

Mass deforestation is one of the most important global environmental problems of our time.

Forest communities play an essential role in the normal functioning of natural ecosystems. They absorb atmospheric pollution of anthropogenic origin, protect the soil from erosion, regulate the normal flow of surface water, prevent the decrease in the level of groundwater and the silting of rivers, canals and reservoirs.

Reducing the area of ​​forests disrupts the cycle of oxygen and carbon in the biosphere.

Despite the fact that the catastrophic consequences of deforestation are already widely known, their destruction continues. Currently, the total area of ​​forests on the planet is about 42 million km2, but it is decreasing by 2% annually. Tropical rainforests are being destroyed especially intensively in Asia, Africa, America and some other regions of the world. So, in Africa, forests used to occupy about 60% of its territory, and now - only about 17%.

The reduction of forests entails the death of their richest flora and fauna. Man impoverishes the appearance of his planet.

In recent years, artificial afforestation and the organization of highly productive forest plantations have been successfully carried out in many countries of the world.

Waste production. Waste from industrial and agricultural production has become a serious environmental problem. Efforts are currently being made to reduce the amount of waste polluting the environment. For this purpose, the most complex filters are being developed and installed, expensive treatment facilities and settling tanks are being built. But practice shows that although they reduce the risk of pollution, they still do not solve the problem. It is known that even with the most advanced treatment, including biological, all dissolved minerals and up to 10% of organic pollutants remain in the treated wastewater. Waters of this quality can become suitable for consumption only after repeated dilution with clean water.

Calculations show that 2200 km 3 of water per year is spent on all types of water use. Almost 20% of the world's fresh water resources are used to dilute wastewater. Calculations for 2012 show that even if the treatment covers all wastewater, it will still require 30-35 thousand km 3 of fresh water to dilute them. This means that the resources of the total world river flow will be close to exhaustion. But in many areas such resources are already in acute shortage.

Obviously, the solution to the problem is possible with the development and introduction into production of completely new, closed, non-waste technologies. When applied, water will not be discharged, but will be reused in a closed cycle. All by-products will not be thrown away as waste, but will be subjected to deep processing. This will create conditions for obtaining additional products that people need and will protect the environment.

Agriculture. In agricultural production, it is important to strictly observe the rules of agricultural technology and monitor the norms of fertilization. Since chemical pest and weed control products lead to significant ecological imbalances, there are several ways to overcome this crisis.

Work is underway to develop plant varieties that are resistant to agricultural pests and diseases: selective bacterial and viral preparations are being created that affect, for example, only insect pests. Ways and means of biological control are being sought, that is, a search is being made for natural enemies that destroy harmful insects. Highly selective drugs are being developed from among hormones, antihormones and other substances that can act on the biochemical systems of certain insect species and not have a noticeable effect on other insect species or other organisms.

Energy production. Very complex environmental problems are associated with the production of energy at thermal power plants. The need for energy is one of the basic human needs. Energy is needed not only for the normal activity of a modern, complexly organized human society, but also for the simple physical existence of every human organism. Currently, electricity is mainly obtained from hydroelectric power plants, thermal and nuclear power plants.

Hydroelectric power plants at first glance are environmentally friendly enterprises that do not harm nature. It has been thought so for many decades. In our country, many of the largest hydroelectric power plants have been built on the great rivers. Now it became clear that this construction caused great damage to both nature and people.

· First of all, the construction of dams on large flat rivers leads to the flooding of vast areas for reservoirs. This is due to the resettlement of a large number of people and the loss of pasture land.

· Secondly, blocking the river, the dam creates insurmountable obstacles on the migration routes of migratory and semi-anadromous fish rising to spawn in the upper reaches of the rivers.

· Thirdly, the water in the reservoirs stagnates, its flow slows down, which affects the lives of all living creatures that live in the river and near the river.

· Fourthly, local water rise affects groundwater, leads to flooding, waterlogging, bank erosion and landslides.

This list of negative consequences of the construction of hydroelectric power stations on lowland rivers can be continued. Large high-altitude dams on mountain rivers are also sources of danger, especially in areas with high seismicity. In world practice, there are several cases when the breakthrough of such dams led to huge destruction and death of hundreds and thousands of people.

From an environmental point of view, nuclear power plants (nuclear power plants) are the cleanest among other currently operating energy complexes. The danger of radioactive waste is fully recognized, therefore, both the design and operating standards of nuclear power plants provide for reliable isolation from the environment of at least 99.999% of all radioactive waste generated.

It should be taken into account that the actual volumes of radioactive waste are relatively small. For a standard nuclear power unit with a capacity of 1 million kW, this is 3-4 m 3 per year.

Not everyone knows that coal has a small natural radioactivity. Since TPPs (thermal power plants) burn huge amounts of fuel, its total radioactive emissions are higher than those of nuclear power plants. But this factor is secondary in comparison with the main disaster from the installation on organic fuel, which is applied to nature and people - emissions into the atmosphere of chemical compounds that are products of combustion.

Although nuclear power plants are more environmentally friendly than mere power plants, they carry great potential hazards in the event of serious reactor accidents.

Conclusion

Warning about the possible consequences of the expanding human intrusion into nature, half a century ago Academician V.I. Vernadsky wrote: "Man becomes a geological force capable of changing the face of the Earth." This warning was prophetically justified. The consequences of anthropogenic activity are manifested in the depletion of natural resources, pollution of the biosphere with industrial waste, radionuclides, destruction of natural ecosystems, changes in the structure of the Earth's surface, and climate change. Anthropogenic impacts lead to disruption of almost all natural biogeochemical cycles.

Due to the increase in the scale of anthropogenic impact, especially in the 20th century, the balance in the biosphere is disturbed, which can lead to irreversible processes and raise the question of the possibility of life on the planet. This is due to the development of industry, energy, transport, agriculture and other human activities without taking into account the possibilities of the Earth's biosphere. Serious environmental problems have already arisen before humanity, requiring immediate solutions.

List of used literature

1. Shilov I.A. Ecology - M.: Higher school, 1998.

2. Golubev G.E., Neoecology - M.: ed. Moscow State University, 1999.

3. Kriksunov E.A., Pasechnik V.V., Sidorin A.P. Ecology - M.: Drofa Publishing House, 1995.

4. Potapov A.D. Ecology - M.: Higher school, 2003.

5. Agadzhanyan, N.A., Torshin V.I. Human Ecology - M.: MMP "Ecocenter", 1994.

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Anthropogenic impacts on individual components of nature. All components of nature to one degree or another experienced the impact of man. In this case, we do not touch on the positive results of human activity: the construction of complex and environmentally friendly reclamation systems, which made it possible to significantly

increase crop yields; introducing new types of cultivated plants into local landscapes; creating wonderful examples of landscape and architectural creativity, etc. We are talking about negative anthropogenic impacts on the environment.
It is generally accepted that vegetation cover serves as a kind of indicator of anthropogenic changes. It is he (however, like the animal world) who first takes the “blow” of a person who decides to develop the territory. In the past, not only farmers, but also nomadic tribes, developing the territory, first of all “intruded” into the natural vegetation cover, often destroying it completely.
It is well known that in order to transform a landscape, it is not at all necessary to change all its components - it is enough to transform one of them, and the balance in the material system will be disturbed, and its other components will also change. In this regard, the role of vegetation is especially noteworthy, which is one of the main factors of soil formation, which has a huge impact on the microclimate, surface runoff, fauna, the cycle of oxygen, carbon dioxide and other biophilic elements.
Soils that were created under conditions that have now disappeared have suffered greatly in historical time, but the fertility of some soils has improved significantly. Cultivated are, for example, anthropogenic old-irrigated soils of oases, soils under vineyards and other agricultural crops. However, to the extent that modern technical possibilities make the soil a well-managed component of the landscape, they also make soil defenseless in case of their unreasonable use.
However, the destruction of soils occurred and occurs sometimes without the use of "ultramodern" technology. Perhaps the most graphic illustration of this is the reduction of vegetation in the arid zone. It is known that the vast expanses of the African savannas are of anthropogenic origin. The leading role in the violation of the ecological balance in this case belongs to the degradation of the soil and vegetation cover.
Today, not only the Sahara is advancing, but the deserts of Southwest Asia, North and South America are also growing. At the same time, deserts advance on steppes, steppes - on savannas, savannas - on moist equatorial forests. The “overload” of fields with agricultural crops and their improper cultivation, deforestation and overgrazing of livestock have led to an increase in the area of ​​arid zones and ongoing soil degradation.
Degradation of cultivated lands, their withdrawal from agricultural circulation occur not only as a result of desertification. They are also "threatened" by human settlements and industry. Cities and villages, industries, power lines and pipelines are quietly crowding croplands, which in turn are encroaching on forests and pastures. Every year, in many countries of the world, the number of territories destroyed by quarries, covered with dumps, formed in the process of extracting mineral raw materials, increases. Many arable lands are flooded by the created reservoirs. The lands withdrawn from agricultural use make up about 10% of the land (Table 2).

Among the anthropogenic impacts on the environment, there are also changes in the Earth's relief associated with mining, agriculture, urban planning and other human activities. Even geomorphologists, along with other forms of relief, often distinguish anthropogenic ones: waste heaps, quarries, dumps, embankments of railway tracks, dams, canals, anti-tank ditches, etc. The indirect influence of man on relief formation is also great, manifested, for example, in the accelerated development of erosion and, respectively, ravines as a result of the intensive use of inconvenient lands without observing the elementary rules of agricultural technology. Without human participation, the formation of many aeolian (with the destruction of vegetation that fixes the sands), thermokarst (with increased thawing of permafrost), biological and other landforms is not complete.

The scale of the transformation of the planet's river network has greatly increased due to the increasing water needs of industry, agriculture, public utilities, etc. .). In themselves, these new anthropogenic landscapes are sometimes admirable, but many data indicate an extremely negative indirect impact of some of them on nature (cutting down forests on watersheds, withdrawing fertile floodplain lands from agricultural use, dehydration of neighboring (often foreign) territories, etc.). P.).

At first glance, the inclusion of human influence on climate in the present topic may seem inappropriate. However, it is well known that the city's atmosphere, which is more polluted than its surroundings, has an effect on reducing the number of hours of sunshine. For example, in winter, Moscow loses about a quarter of sunshine and has a higher air temperature, since numerous heating systems and power plants play the role of heaters.

Finally, anthropogenic activity has had a tremendous impact on the animal world, many of whose representatives have either already been destroyed or are on the verge of extinction. By impoverishing the natural complex, we grossly violate the historically established links between the animal world and vegetation, the animal world and soils, etc. In other words, man interferes with the traditional course of biochemical cycles of substances in the earth's crust (Table 2).

Land category	Square
	million km 2	%
Glaciers	16,3	11,0
Polar and alpine subnival deserts	5,0	3,3
Tundra and forest tundra	7,0	4,7
Swamps outside the tundra	4,0	2,7
Lakes, swamps, rivers, reservoirs	3,2	2,1
Non-irrigated arid deserts, rocky soils and coastal sands	18,2	12,2
Forests, including those planted by man	40,3	27,0
Herbaceous-shrub pastures and natural meadows	28,5	19,0
Agricultural areas - arable lands, gardens, plantations, sown meadows, including villages, country roads, roadsides, etc.	19,0	13,0
Industrial and urban lands, including mining and ground communications	3,0	2,0
Anthropogenic badlands (lands subject to erosion, salinization and waterlogging, etc.)	4,5
Land in general	149	100

1. Compare the natural areas of South America and Africa. What are their similarities and differences?

Since the equator crosses Africa in the middle, the placement of natural zones will be symmetrical, and South America is crossed by the equator in its northern part, therefore, the placement of natural zones will occur in a latitudinal direction.

Both continents are located in the natural zone of moist equatorial forests. On both continents, red-yellow ferralitic soils have formed in the zone of equatorial forests. These territories on both continents are characterized by rich multi-layered vegetation and wildlife.

The savannah zone is formed in a subequatorial climate. Savannahs in South America occupy a much smaller area than in Africa. This is due to the fact that Africa has a large extent from west to east and lies on both sides of the equator. Also, in South America, the flora and fauna of this natural area is poorer than in Africa. In the savannas of South America, there are no large animals, such as elephant, giraffe, rhinoceros, which are found in Africa.

The steppe zone is present only on the mainland of South America. It is characterized by a drier climate and grassy vegetation.

There is a zone of tropical deserts on both continents. In Africa, deserts occupy a huge area, including the Sahara Desert. There are no inland deserts in South America, only coastal ones.

2. Do practical work. According to the ecological map (see Fig. 106), select the areas and centers of the greatest and least anthropogenic impact on nature. Please rate these facts.

The greatest changes in nature are in those natural zones where the population is large. these are the natural zones of the savannas and pampas, as well as the variable-moist forests of the Atlantic coast.

3. In what natural areas have the largest number of national parks and reserves been created? Why?

In humid equatorial forests, because these areas are most exposed to human influence.

4. Geographers consider South America the mainland of many natural "records". Name at least six of them, if you have difficulty, refer to the text of the textbook.

1. The river with the largest water flow in the world is the Amazon.

3. The largest biodiversity - Amazonian equatorial forests (tree species only - 800)

4. The highest mountain lake in the world is located in the caldera of the dormant volcano Ojos del Salado at an altitude of 6680 m above sea level

5. The longest land mountain range in the world is the Andes (there are longer ones, if we talk about the Earth at all - the Mid-Atlantic Ridge)

6. Chile is the only major country on the continents of the world where there are no poisonous snakes at all.

7. The strongest earthquake in the observation period - the Great Valdivian earthquake, May 20-22, 1960, Valdivia province, Chile, magnitude 9.5.

8. The highest active volcano in the world - Llyullyalyaiko (Chile).

9. The highest volcano on Earth - Aconcagua - is located on the border of Argentina and Chile. This is the highest point in Argentina.

10. Chuquicamata - the largest operating copper mine in the world (Chile, Calama province)

5. Play a game: write a description of a natural area on behalf of a scientist who is exploring this area. Determine the winner of the best description.

We are going to the selva - a zone of humid equatorial forests. We immediately enter the world of greenery. These forests are multi-tiered, evergreen. They are very hot and humid. The first tier is made up of huge trees, entwined with lianas of different thicknesses. They often have very beautiful orchids. You can find a melon tree, hevea, cocoa. The largest water lily on Earth, Victoria Regia, grows in rivers. Everywhere a huge number of insects, among them giant butterflies. Among large animals, you can meet tapirs and the largest rodent on Earth - the capybara. On the trees we see birds with multi-colored plumage, many monkeys. Here you can meet the largest boa constrictor - the anaconda, and among the predators - the jaguar, puma, ocelot.

In the last 100 years, humanity has begun to have a noticeable impact on the functioning of the biosphere.

In the prehistoric phase, people lived in conditions of energy deficiency and were forced to protect a huge fodder territory, in which they periodically or constantly wandered. And, despite this, for a long time they were within a very modest energy balance.

Energy consumption per person (kcal / day) in the Stone Age was about 4 thousand, in an agrarian society - 12 thousand, in the industrial era - 70 thousand, and in advanced developed countries of the late twentieth century - 230-250 thousand, tons .e. 58-62 times more than our distant ancestors.

Population growth requires an increase in food, the creation of new jobs and the expansion of industrial production. At the first stages, a person interacted with the natural environment as an ordinary biological species, as an animal, and as a whole was part of the ecosystem, as its constituent element. Man mainly used the resources surrounding him and practically did not affect either their quantity or their quality, and could not have any tangible impact on nature, both due to its small number and the presence of any significant means of influencing the components of the environment. .

Having formed a human society, it went through the following stages of interaction with nature:

The transition to the production and use of tools as the first (link in the relationship between people and nature;

The transition to artificial energy production has expanded (opportunities in the transformation of nature;

Industrial and scientific and technological revolution;

Artificial reproduction and preservation of the environment - protonosphere.

At the end of the second millennium, population growth, and mainly a qualitative leap in the development of science and technology, led to the fact that anthropogenic impacts, in terms of their significance for the biosphere, reached the same level as natural planetary ones. The transformation of landscapes into cities and other human settlements, into agricultural lands and industrial complexes has already covered more than 20% of the land area. Oxygen consumption in industry and transport is on the scale of the entire biosphere about 10% of the planetary production of photosynthesis; in some countries, man-made oxygen consumption exceeds its production by plants. In our time, anthropogenic impact is becoming the guiding force for the further evolution of ecosystems.

Anthropogenic impacts subdivided into:

pollution- introduction into the environment of new physical, chemical or biological agents (elements, compounds, substances, objects) that are not characteristic of it or exceeding the existing natural level of these agents;

technical transformations and destruction of natural systems and landscapes - in the process of extracting natural resources, during agricultural work, construction, etc.;

depletion of natural resources(minerals, water, air, biological components of ecosystems);

global climate impacts(climate change due to human economic activity);

aesthetic disturbances(change in natural forms, unfavorable for visual and other perception; destruction of historical and cultural values, etc.).

As a result, a person affects the biosphere and changes the composition, circulation and balance of substances; heat balance of the near-surface part of the Earth; the structure of the earth's surface (during agricultural work, moving exposed rocks; quarrying, as a result of urban development, during road construction; during the construction of artificial reservoirs - canals, reservoirs, land reclamation, etc.); exterminating, as well as moving a number of animal species and plant varieties to new habitats.

Under the conditions of anthropogenic loads, for the sustainable functioning of ecosystems, a person must himself play the role of a compensatory regulator, planting trees on the ground in places of cut forests, purifying water, air, etc.

pollution subdivided depending on the type, source, consequences and control measures into: sewage and other sewage that absorb oxygen; carriers of the infection; substances of nutritional value for plants; minerals and inorganic acids and salts; solid drains; radioactive substances, etc.

It should be noted that, in principle, pollution can be natural, arising as a result of powerful natural processes - volcanic eruptions with huge emissions of dust, ash, gases, steam, etc.; forest and steppe fires; floods; dust and sand storms, etc.

It is necessary to dwell on such an important concept, which is widely used in modern ecological and environmental literature, as pollutant. It refers to any physical agent, chemical substance or biological species (mainly microorganisms) entering or appearing in the environment in quantities beyond the ordinary, and causing environmental pollution. Allocate natural (natural , anthropogenic, as well as primary (directly from the source of pollution and secondary (during the decomposition of primary, or chemical reactions with them). It also distinguishes between persistent (non-decomposing pollutants that accumulate in trophic chains.

The entry of various pollutants into the natural environment can have a number of undesirable consequences: damage to vegetation and wildlife (decrease in the productivity of forests and cultivated plants, extinction of animals); violation of the stability of natural biogeocenoses; damage to property (corrosion of metals, destruction of architectural structures, etc.); harm to human health, etc.

Many of the pollutants (pesticides, polychlorinated biphenyls, plastics) decompose extremely slowly in natural conditions, and toxic compounds (mercury, lead) are not neutralized at all.

If until the 40s of the 20th century natural products still dominated (cotton, silk, wool, soap, rubber, food free of additives, etc.), then at present in industrialized countries, they are replaced by synthetic ones, which difficult or incompletely decompose and pollute the environment. These are primarily synthetic fibers, detergents (detergents, bleaches), food with additives, mineral fertilizers, synthetic rubber, etc.

Especially a lot of pollutants entering the environment are formed when energy is obtained from the combustion of fossil fuels. A person, releasing solar energy in this way, accelerates the circulation of substances and energy in nature. Production waste and atmospheric pollutants (carbon monoxide, nitrogen oxides, hydrocarbons, solid particles, etc.) disrupt the natural carbon cycle, contributing to a number of negative consequences (greenhouse effect, photochemical smog, etc.). A large number of pollutants enter the atmosphere from various industries, in particular, the metallurgical enterprises of the world annually emit more than 150 thousand tons of copper, 120 thousand tons of zinc, 90 thousand tons of nickel, cobalt, mercury. Thus, the Norilsk Mining and Metallurgical Plant annually emits up to 2200 thousand tons of sulfur compounds alone into the atmosphere, which leads to the death of a significant number of plant communities, creating a significant threat to the health and life of many other living organisms. Within a radius of up to 120 km from the plant there is no natural regeneration of trees, and the annual growth and primary biological productivity are minimal.