We all live on one planet - Earth. We breathe the same air earth's atmosphere. Harmful emissions into the air over any area after some time spread throughout the planet. A sea currents, despite state borders, carry around the globe all the dirt that people dump into the World Ocean.
The problems of exhaustibility of mineral, forest, land and other resources concern all people, no matter where they live - in Europe, Asia, Africa, Australia or America. Therefore, the consequences of environmental exposure caused by economic activity person, is now felt by the whole world. Therefore, the problem of interaction between man, society and nature requires, for its solution, not the efforts of individual countries, but international cooperation.
Remember
Due to what bonds are natural complexes formed?
What is integrity geographic envelope? (See § 59).
Human economic activity is an activity aimed at obtaining useful products. It can be food and clothing, wood and minerals, fish and animal meat, cars and airplanes, and the like.
A significant part of useful products is produced at various industrial enterprises- plants, factories, combines, power plants (Fig. 196), mines and the like.
In addition, agriculture provides many useful products. Its important industries are crop production and livestock farming. Crop farming is associated with the cultivation of cultivated plants, in particular grains, oilseeds, vegetables and the like. The purpose of livestock farming is to breed cattle, pigs, sheep, birds, and fish. These sectors of the economy provide humanity with food and raw materials for industry.
Rice. 196. Thermal power plant
Rice. 197. Road transport
Facts of our time
Pet animals. More than 12 thousand years ago, people began to domesticate animals. In total, about 6,200 different breeds were created. The most beloved domestic animals among birds are chickens, ducks, geese, turkeys, and among mammals - cattle, horses, pigs, buffaloes, donkeys, sheep and goats.
Transport plays an extremely important role in human life and economic activity - railway, road, water, air, etc. (Fig. 197). It is used to transport people and goods.
Changes in the components of nature by man - providing the components with new features and properties. Man has long interfered with nature and changed its individual components, adapting it to his needs. After all, she needs to eat, drink, dress, build housing.
Geography of culture
"Transformers" of nature. How exactly man changed natural components is reflected even in folk tales. So, the heroes of the famous Ukrainian fairy tale“Kotigoroshko” is Vernigora, Vernidub, Krutius. Vernigora could destroy mountains. Vernidub uprooted trees. Crutius blocked the path of the river and returned the water. Nowadays, man is so actively modifying nature that the result of the activities of the modern “Vernigora” can be considered the quarries left after the extraction of minerals, filled with “mountains” from waste. Thanks to the activities of “Vernidub”, huge tracts of tropical forests have now disappeared in South America, Africa and the like. “Krutius” built dams and reservoirs on the rivers and almost dried up the Aral Sea.
Rice. 198. Subway tracks (1), overpass (2)
Changes in the lithosphere. The extraction of various minerals disrupts the relief of the globe. IN different corners world you can see numerous quarries and mines, humps of waste from processing factories. Sometimes due to the formation of voids in the upper part of the lithosphere and on earth's surface subsidence and dips occur, in some places by 2-5 m. Such shifts rocks They are found, in particular, on the territory of Ukraine, in the Donetsk coal and Dnepropetrovsk lignite basins.
The surface of the lithosphere is also greatly modified by embankments, the construction of overpasses, the laying of numerous roads, subway tracks, and the like (Fig. 198).
Changes in the hydrosphere. In order to protect them from river floods, they are often “dressed” in “concrete banks” or sharpened into pipes (Fig. 199). Through the construction of reservoirs and water “roads” - locks - the regime of rivers is disrupted, the conditions of existence change aquatic organisms. Among the artificial reservoirs that man has created, there are numerous bets that are often used for growing fish.
Rice. 199. River encased in concrete (1), locks on the Dnieper (2)
"Sick" lakes. For the well-known Shatsk lakes in Ukrainian Polesie, the difficult times. As a result of the construction of drainage systems near lakes in the surrounding area, the groundwater level has decreased, and the area of the lakes themselves has also decreased. Five lakes of the Shatsk group have already completely disappeared.
Changes in the atmosphere. As a result of human economic activity, the composition of air changes, in particular, the content increases carbon dioxide in the atmosphere. It, like the glass of a greenhouse, retains solar heat at the earth's surface. This causes the temperature to rise throughout globe, and consequently, a gradual warming of the planet’s climate. This phenomenon is called the greenhouse effect.
IN lately education is a growing concern ozone holes. This is associated, in particular, with atmospheric emissions from industrial and household waste, using freons - artificially created substances.
Changes in the biosphere. Since ancient times, man began to grow cultivated plants and breed domestic animals, changing and often destroying wildlife. For example, for the purpose of fertilizing the soil or for happy hunting In the savannas of Africa, shrubs and grasses were burned. As a result, the climate has changed: it has become speculative and arid. After all, the exposed earth warmed up more, and precipitation became extremely rare.
It was man who became responsible for the fact that many plants and animals were artificially relocated from their usual living environment to new conditions. Thus, wheat and corn, cabbage and beets, potatoes and peppers, cucumbers and tomatoes and many other plants that became vital for us were brought to Europe and introduced into cultivation here. Nowadays, the objects of artificial relocation are mainly rare plants and valuable animals that are bred for economic needs or for sale.
Changes in the natural complexes of the Earth - providing complexes with new features and properties. One of the impressive consequences of human activity is, in particular, the reduction in the area of the famous Asian tropical rain forests. This is not only the loss of numerous representatives of wildlife, but also the acceleration of soil destruction. In addition, it has been proven that due to the destruction of forests in the tropics, significant climate changes can occur even in temperate latitudes.
Facts of our time
Forest zones are melting. In Laos, where in the first half of the 20th century. Almost the entire country was covered with impenetrable tropical thickets, the forests had already been cut down by half. More than double compared to the state in the middle of the 20th century. The area under forests has decreased in the Philippines, and in Thailand - by more than three times. One of the largest islands in the world - Kalimantan - 100 years ago, 95% of its area was covered tropical forests. Now they have survived only on 2/3 of the territory.
"Window" to Ukraine
We are losing forests. Ukraine is a sparsely forested state. And, unfortunately, the area of our forests in many regions is steadily decreasing (Fig. 200). Irreparable damage to forests is caused by fires, predatory logging, and emissions of toxic industrial waste. Most forests are dying in the south and southeast of the country.
Overgrazing by livestock, particularly goats, has also destroyed forests in the Mediterranean. There even the expression was born: “The goats ate the Mediterranean.” Also famous expression: “The sheep ate the Asian steppes.” As a result, the climate becomes arid, soil destruction increases and, finally, the onset of deserts.
An example of a noticeable increase in the area of deserts due to human fault can be the region of the Aral Sea-Lake. And this began when more water began to be taken from the Syr Darya and Amudarya rivers, which flowed into the Aral Sea-Lake, than could be done. The sea began to rapidly dry out, and its former bottom turned into a desert.
Rice. 200. Deforestation in the Carpathians
Natural complexes are also disturbed when construction is made on rivers. large reservoirs. As a result, it changes local climate, nearby lands are flooded, soil destruction is intensifying, cases of landslides are becoming more frequent, and the like.
Human economic activity is an activity aimed at obtaining useful products.
Changes in the components of nature and natural complexes of the Earth - providing them with new features and properties.
Questions and tasks for self-test
Explain on specific examples, why not only individual natural ingredients and natural complexes. Give examples of changes in nature in your area under the influence of human economic activity.
Explain how various components of nature might change as a result various types human economic activity.
Give examples of useful products that a person receives due to his economic activities.
In accordance with population density, the degree of human impact on the environment also changes. However, at the current level of development of productive forces, the activities of human society affect the biosphere as a whole. Humanity, with its social laws of development and powerful technology, is quite capable of influencing the centuries-old course of biosphere processes.
Air pollution. In the process of their activities, people pollute air environment. Over cities and industrial areas in the atmosphere, the concentration of gases increases, which rural areas contained in very small quantities or completely absent. Polluted air is harmful to health. In addition, harmful gases, combining with atmospheric moisture and falling in the form of acid rain, deteriorate the quality of the soil and reduce crop yields.
The main causes of air pollution are the combustion of natural fuels and metallurgical production. If in the 19th century those entering environment Since the combustion products of coal and liquid fuel have been almost completely assimilated by the vegetation of the Earth, at present the content of harmful combustion products is steadily increasing. A number of pollutants enter the air from stoves, furnaces, and car exhaust pipes. Among them, sulfur dioxide is especially prominent - a poisonous gas that is easily soluble in water.
The concentration of sulfur dioxide in the atmosphere is especially high in the vicinity of copper smelters. It causes the destruction of chlorophyll, underdevelopment of pollen grains, drying and falling of pine leaves. Some SO 2 is oxidized to sulfuric anhydride. Solutions of sulfuric and sulfuric acids, falling with rain on the surface of the Earth, cause harm to living organisms and destroy buildings. The soil becomes acidic, and humus (humus) is washed out of it - an organic substance containing components necessary for the development of plants. In addition, it reduces the amount of calcium, magnesium, and potassium salts. In acidic soils, the number of animal species living in it decreases, and the rate of decomposition slows down. All this creates unfavorable conditions for plant growth.
Every year, billions of tons of CO 2 are released into the atmosphere as a result of fuel combustion. Half of the carbon dioxide produced by the combustion of fossil fuels is absorbed by the ocean and green plants, while half remains in the air. The CO 2 content in the atmosphere is gradually increasing and has increased by more than 10% over the past 100 years. CO 2 prevents thermal radiation into outer space, creating the so-called “greenhouse effect”. Changes in CO 2 content in the atmosphere significantly affect the Earth's climate.
Industrial enterprises and cars cause the release of many toxic compounds into the atmosphere - nitrogen oxide, carbon monoxide, lead compounds (each car emits 1 kg of lead per year), various hydrocarbons - acetylene, ethylene, methane, propane, etc. Together with droplets of water they form a toxic fog - smog, which has a harmful effect on the human body and the vegetation of cities. Liquid and solid particles (dust) suspended in the air reduce the amount of solar radiation reaching the Earth's surface. Thus, in large cities, solar radiation decreases by 15%, ultraviolet radiation– by 30% (and in winter months it may disappear completely).
Fresh water pollution. Extent of use water resources are increasing rapidly. This is due to population growth and improvement of sanitary and hygienic conditions of human life, the development of industry and irrigated agriculture. Daily water consumption for household needs in rural areas is 50 liters per person, in cities – 150 liters.
Huge amounts of water are used in industry. To melt 1 ton of steel, 200 m 3 of water is required, and to produce 1 ton of synthetic fiber - from 2500 to 5000 m 3. Industry absorbs 85% of all water used in cities.
Even more water is needed for irrigation. During the year, 12-14 m3 of water is consumed per 1 hectare of irrigated land. In our country, more than 150 km 3 is spent annually on irrigation.
The constant increase in water consumption on the planet leads to the danger of “water famine”, which necessitates the development of measures for the rational use of water resources. In addition to the high level of consumption, the shortage of water is caused by its growing pollution due to the discharge of industrial and especially chemical waste into rivers. Bacterial pollution and toxic chemicals (for example, phenol) lead to the death of water bodies. The rafting of timber along rivers, which is often accompanied by congestion, also has harmful consequences. When wood stays in water for a long time, it loses business qualities, and the substances washed out from it have a detrimental effect on fish.
They are also washed out of the soil by rain and enter rivers and lakes. mineral fertilizers- nitrates and phosphates, which in high concentrations can dramatically change the species composition of water bodies, as well as various pesticides - pesticides used in agriculture to control insect pests. For aerobic organisms living in fresh waters, the discharge of warm water by enterprises is also an unfavorable factor. Oxygen is poorly soluble in warm water and its deficiency can lead to the death of many organisms.
Pollution of the World Ocean. The waters of the seas and oceans are subject to significant pollution. WITH river flow, as well as from maritime transport, pathogenic waste, oil products, salts enter the seas heavy metals, toxic organic compounds, including pesticides. Pollution of the seas and oceans reaches such proportions that in some cases caught fish and shellfish are unsuitable for consumption.
Anthropogenic changes in the soil. The fertile layer of soil takes a very long time to form. At the same time, tens of millions of tons of nitrogen, potassium, and phosphorus, the main components of plant nutrition, are removed from the soil every year along with the harvest. Humus, the main factor of soil fertility, is contained in chernozems in an amount of less than 5% of the mass of the arable layer. On poor soils there is even less humus. In the absence of soil replenishment with nitrogen compounds, its supply can be used up in 50-100 years. This does not happen, since cultural farming involves the introduction of organic and inorganic (mineral) fertilizers into the soil.
Nitrogen fertilizers applied to the soil are used by plants by 40-50%. The rest is reduced by microorganisms to gaseous substances, evaporates into the atmosphere or is washed out of the soil. Thus, mineral nitrogen fertilizers are quickly consumed, so they have to be applied annually. With insufficient use of organic and inorganic fertilizers, the soil is depleted and yields fall. Unfavorable changes in the soil also occur as a result of incorrect crop rotations, i.e., annual sowing of the same crops, for example potatoes.
Anthropogenic soil changes include erosion (corrosion). Erosion represents destruction and demolition soil cover by currents of water or wind. Widespread and most destructive water erosion. It occurs on slopes and develops due to improper cultivation of the land. Together with melt and rainwater, millions of tons of soil are carried away from fields into rivers and seas every year. If nothing prevents erosion, small gullies turn into deeper ones and, finally, into ravines.
Wind erosion occurs in areas with dry, bare soil and sparse vegetation cover. Excessive grazing in steppes and semi-deserts contributes to wind erosion and rapid destruction of grass cover. It takes 250-300 years to restore a 1 cm thick layer of soil under natural conditions. Consequently, dust storms bring irreparable loss of fertile soil layer.
Significant territories with formed soils are withdrawn from agricultural use due to the open-pit mining method for minerals lying at shallow depths. The open-pit mining method is cheap, as it eliminates the need to build expensive mines and a complex communications system, and is also safer. Dug deep quarries and dumps of soil destroy not only the lands to be developed, but also the surrounding areas, while the hydrological regime of the area is disrupted, water, soil and atmosphere are polluted, and agricultural yields are reduced.
Human influence on plant and fauna. Human impact on wildlife consists of direct influence and indirect changes in the natural environment. One form of direct impact on plants and animals is forest cutting. Selective and sanitary cuttings, which regulate the composition and quality of the forest and are necessary to remove damaged and diseased trees, do not significantly affect the species composition of forest biocenoses. Another thing is clear cutting of trees. Finding themselves suddenly in open habitat conditions, plants in the lower tiers of the forest experience the adverse effects of direct solar radiation. In shade-loving plants of the herbaceous and shrub layers, chlorophyll is destroyed, growth is inhibited, and some species disappear. Light-loving plants that are resistant to elevated temperatures and lack of moisture settle in the felled areas. The animal world is also changing: species associated with the tree stand disappear or migrate to other places.
Mass visits to forests by vacationers and tourists have a noticeable impact on the state of vegetation. In these cases harmful influence consists of trampling, soil compaction and contamination. Direct influence man's influence on the animal world consists in the extermination of species that provide him with food or other material benefits. It is believed that since 1600, more than 160 species and subspecies of birds and at least 100 species of mammals have been exterminated by humans. The long list of extinct species includes the aurochs, a wild bull that lived throughout Europe. In the 18th century was exterminated, described by the Russian naturalist G.V. Steller's sea cow (Steller's cow) is an aquatic mammal belonging to the order Sirenidae. A little over a hundred years ago, the wild Tarpan horse, which lived in southern Russia, disappeared. Many animal species are on the verge of extinction or are preserved only in nature reserves. Such is the fate of the bison, which inhabited the prairies of North America by the tens of millions, and the bison, formerly widespread in the forests of Europe. In the Far East, sika deer have been almost completely exterminated. Intensified fishing for cetaceans has brought several species of whales to the brink of destruction: gray, bowhead, and blue.
The number of animals is also influenced by human economic activities not related to fishing. The number of Ussuri tigers has sharply decreased. This occurred as a result of the development of territories within its range and a reduction in the food supply. IN Pacific Ocean Every year, several tens of thousands of dolphins die: during the fishing season, they get caught in nets and cannot get out of them. Until recently, before fishermen took special measures, the number of dolphins dying in nets reached hundreds of thousands. The effects of water pollution are very unfavorable for marine mammals. In such cases, a ban on catching animals is ineffective. For example, after the ban on catching dolphins in the Black Sea, their numbers have not recovered. The reason is that in the Black Sea from river water and through the straits from the Mediterranean Sea comes a lot toxic substances. These substances are especially harmful to baby dolphins, whose high mortality rate prevents the growth of the population of these cetaceans.
The disappearance of a relatively small number of animal and plant species may not seem very significant. Each species occupies a certain place in the biocenosis, in the chain, and no one can replace it. The disappearance of one or another species leads to a decrease in the stability of biocenoses. More importantly, each species has unique properties that are unique to it. The loss of genes that determine these properties and were selected during long-term evolution deprives a person of the opportunity in the future to use them for his practical purposes (for example, for selection).
Radioactive contamination of the biosphere. The problem of radioactive contamination arose in 1945 after the explosion of atomic bombs dropped on Japanese cities Hiroshima and Nagasaki. Nuclear weapons tests carried out in the atmosphere before 1963 caused global radioactive contamination. When atomic bombs explode, very strong ionizing radiation is generated; radioactive particles are scattered over long distances, contaminating the soil, water bodies, and living organisms. Many radioactive isotopes have a long half-life, remaining dangerous throughout their existence. All these isotopes are included in the cycle of substances, enter living organisms and have a detrimental effect on cells.
Testing nuclear weapons (and even more so when using these weapons for military purposes) has another negative side. During a nuclear explosion, a huge amount of fine dust is formed, which remains in the atmosphere and absorbs a significant part of solar radiation. Calculations by scientists from around the world show that even with limited, local application nuclear weapons the resulting dust will block most of the solar radiation. There will be a long cold snap (“ nuclear winter"), which will inevitably lead to the death of all life on Earth.
Currently, almost any territory of the planet from the Arctic to Antarctica is subject to diverse anthropogenic influences. The consequences of the destruction of natural biocenoses and environmental pollution have become very serious. The entire biosphere is under increasing pressure from human activity, so environmental protection measures are becoming an urgent task.
Acidic atmospheric deposition on land. One of the most pressing global problems of our time and the foreseeable future is the problem of increasing acidity of atmospheric precipitation and soil cover. Areas of acidic soils do not experience droughts, but their natural fertility is reduced and unstable; They are quickly depleted and their yields are low. Acid rain causes more than just acidification surface waters and upper soil horizons. Acidity with downward flows of water spreads across the entire soil profile and causes significant acidification of groundwater. Acid rain occurs as a result of human economic activity, accompanied by the emission of colossal amounts of oxides of sulfur, nitrogen, and carbon. These oxides, entering the atmosphere, are transported over long distances, interact with water and turn into solutions of a mixture of sulfuric, sulfuric, nitrous, nitric and carbonic acids, which fall in the form of “acid rain” on land, interacting with plants, soils, and waters. The main sources in the atmosphere are the combustion of shale, oil, coal, gas in industry, in agriculture, in everyday life. Human economic activity has almost doubled the release of oxides of sulfur, nitrogen, hydrogen sulfide and carbon monoxide into the atmosphere. Naturally, this affected the increase in acidity of atmospheric precipitation, ground and ground waters. To solve this problem, it is necessary to increase the volume of systematic representative measurements of compounds of air pollutants over large areas.
1Currently, humanity lives in an era scientific and technological progress providing great influence on natural environment. Over the past decades, measures have been taken to protect, preserve and restore it, but still, in general, the state of the natural environment continues to gradually deteriorate. In this era, the area of influence of human economic activity on the natural environment is becoming even larger.
Economic activity affects not only directly, but also indirectly the atmosphere and the processes occurring in it. Human economic activity has a particularly strong impact on the climate of entire regions - deforestation, plowing of land, large reclamation works, mining, burning of fossil fuels, military operations, etc. Human economic activity does not disrupt the geochemical cycle, and also has a significant impact on the energy balance in nature. As a result of human economic activity, various chemical compounds, which are tens of times higher than the appearance of substances during the weathering of rocks and volcanoes. In some regions with large populations and industrial production the volumes of generated energy have become comparable to the energy of the radiation balance and have a great influence on changes in the microclimate. Based on the results of studies, checking the amount of oxygen in the atmosphere, it was determined that the decrease occurs by more than 10 million tons per year. Consequently, the carbon dioxide content in the atmosphere can reach critical situation. According to the calculations of some scientists, it is known that doubling the amount of CO 2 in the atmosphere will increase average temperature Earth by 1.5-2 degrees due to " greenhouse effect. Due to rising temperatures, glaciers are rapidly melting, which leads to a serious change in the entire surrounding world, and a possible rise in the level of the World Ocean by 5 m.
Thus, human economic activities have a detrimental effect on the natural environment.
Bibliographic link
Kalyakin S.I., Chelyshev I.S. IMPACT OF HUMAN ECONOMIC ACTIVITIES ON THE NATURAL ENVIRONMENT // Advances modern natural science. – 2010. – No. 7. – P. 11-12;URL: http://natural-sciences.ru/ru/article/view?id=8380 (access date: 03/31/2019). We bring to your attention magazines published by the publishing house "Academy of Natural Sciences"
In accordance with population density, the degree of human impact on the environment also changes. However, at the current level of development of productive forces, the activities of human society affect the biosphere as a whole. Humanity, with its social laws of development and powerful technology, is quite capable of influencing the centuries-old course of biosphere processes.
Air pollution. In the course of their activities, people pollute the air. Over cities and industrial areas in the atmosphere, the concentration of gases increases, which in rural areas are contained in very small quantities or are completely absent. Polluted air is harmful to health. In addition, harmful gases, combining with atmospheric moisture and falling in the form of acid rain, deteriorate the quality of the soil and reduce crop yields.
The main causes of air pollution are the combustion of natural fuels and metallurgical production. If in the 19th century the products of combustion of coal and liquid fuel entering the environment were almost completely assimilated by the vegetation of the Earth, now the content of harmful combustion products is steadily increasing. A number of pollutants enter the air from stoves, furnaces, and car exhaust pipes. Among them, sulfur dioxide is especially prominent - a poisonous gas that is easily soluble in water.
The concentration of sulfur dioxide in the atmosphere is especially high in the vicinity of copper smelters. It causes the destruction of chlorophyll, underdevelopment of pollen grains, drying and falling of pine leaves. Some SO 2 is oxidized to sulfuric anhydride. Solutions of sulfuric and sulfuric acids, falling with rain on the surface of the Earth, cause harm to living organisms and destroy buildings. The soil becomes acidic, and humus (humus) is washed out of it - an organic substance containing components necessary for the development of plants. In addition, it reduces the amount of calcium, magnesium, and potassium salts. In acidic soils, the number of animal species living in it decreases, and the rate of decomposition of litter is slowed down. All this creates unfavorable conditions for plant growth.
Every year, billions of tons of CO 2 are released into the atmosphere as a result of fuel combustion. Half of the carbon dioxide produced by the combustion of fossil fuels is absorbed by the ocean and green plants, while half remains in the air. The CO 2 content in the atmosphere is gradually increasing and has increased by more than 10% over the past 100 years. CO 2 prevents thermal radiation into outer space, creating the so-called “greenhouse effect”. Changes in CO 2 content in the atmosphere significantly affect the Earth's climate.
Industrial enterprises and cars cause the release of many toxic compounds into the atmosphere - nitrogen oxide, carbon monoxide, lead compounds (each car emits 1 kg of lead per year), various hydrocarbons - acetylene, ethylene, methane, propane, etc. Together with droplets of water they form a toxic fog - smog, which has a harmful effect on the human body and the vegetation of cities. Liquid and solid particles (dust) suspended in the air reduce the amount of solar radiation reaching the Earth's surface. Thus, in large cities, solar radiation decreases by 15%, ultraviolet radiation by 30% (and in the winter months it may completely disappear).
Fresh water pollution. The use of water resources is increasing rapidly. This is due to population growth and improvement of sanitary and hygienic conditions of human life, the development of industry and irrigated agriculture. Daily water consumption for household needs in rural areas is 50 liters per person, in cities – 150 liters.
Huge amounts of water are used in industry. To melt 1 ton of steel, 200 m 3 of water is required, and to produce 1 ton of synthetic fiber - from 2500 to 5000 m 3. Industry absorbs 85% of all water used in cities.
Even more water is needed for irrigation. During the year, 12-14 m3 of water is consumed per 1 hectare of irrigated land. In our country, more than 150 km 3 is spent annually on irrigation.
The constant increase in water consumption on the planet leads to the danger of “water famine”, which necessitates the development of measures for the rational use of water resources. In addition to the high level of consumption, the shortage of water is caused by its growing pollution due to the discharge of industrial and especially chemical waste into rivers. Bacterial pollution and toxic chemicals (for example, phenol) lead to the death of water bodies. The rafting of timber along rivers, which is often accompanied by congestion, also has harmful consequences. When wood remains in water for a long time, it loses its commercial qualities, and the substances washed out of it have a detrimental effect on fish.
Rivers and lakes also receive mineral fertilizers washed out of the soil by rain - nitrates and phosphates, which in high concentrations can dramatically change the species composition of water bodies, as well as various pesticides - pesticides used in agriculture to control insect pests. For aerobic organisms living in fresh waters, discharge from enterprises is also an unfavorable factor. warm waters. Oxygen is poorly soluble in warm water and its deficiency can lead to the death of many organisms.
Pollution of the World Ocean. The waters of the seas and oceans are subject to significant pollution. With river runoff, as well as from sea transport, pathogenic waste, petroleum products, salts of heavy metals, toxic organic compounds, including pesticides, enter the seas. Pollution of the seas and oceans reaches such proportions that in some cases caught fish and shellfish are unsuitable for consumption.
Anthropogenic changes in the soil. The fertile layer of soil takes a very long time to form. At the same time, tens of millions of tons of nitrogen, potassium, and phosphorus, the main components of plant nutrition, are removed from the soil every year along with the harvest. Humus, the main factor of soil fertility, is contained in chernozems in an amount of less than 5% of the mass of the arable layer. On poor soils there is even less humus. In the absence of soil replenishment with nitrogen compounds, its supply can be used up in 50-100 years. This does not happen, since cultural farming involves the introduction of organic and inorganic (mineral) fertilizers into the soil.
Nitrogen fertilizers applied to the soil are used by plants by 40-50%. The rest is restored by microorganisms to gaseous substances, evaporates into the atmosphere or is washed out of the soil. Thus, mineral nitrogen fertilizers are quickly consumed, so they have to be applied annually. With insufficient use of organic and inorganic fertilizers, the soil is depleted and yields fall. Unfavorable changes in the soil also occur as a result of incorrect crop rotations, i.e., annual sowing of the same crops, for example potatoes.
Anthropogenic soil changes include erosion (corrosion). Erosion is the destruction and removal of soil cover by water flows or wind. Water erosion is widespread and most destructive. It occurs on slopes and develops due to improper cultivation of the land. Together with melt and rainwater, millions of tons of soil are carried away from fields into rivers and seas every year. If nothing prevents erosion, small gullies turn into deeper ones and, finally, into ravines.
Wind erosion occurs in areas with dry, bare soil and sparse vegetation cover. Excessive grazing in steppes and semi-deserts contributes to wind erosion and rapid destruction of grass cover. It takes 250-300 years to restore a 1 cm thick layer of soil under natural conditions. Consequently, dust storms bring irreparable loss of fertile soil layer.
Significant territories with formed soils are withdrawn from agricultural use due to the open-pit mining method for minerals lying at shallow depths. The open-pit mining method is cheap, as it eliminates the need to build expensive mines and a complex communications system, and is also safer. Dug deep quarries and dumps of soil destroy not only the lands to be developed, but also the surrounding areas, while the hydrological regime of the area is disrupted, water, soil and atmosphere are polluted, and agricultural yields are reduced.
Human influence on flora and fauna. Human impact on wildlife consists of direct influence and indirect changes in the natural environment. One form of direct impact on plants and animals is forest cutting. Selective and sanitary cuttings, which regulate the composition and quality of the forest and are necessary to remove damaged and diseased trees, do not significantly affect the species composition of forest biocenoses. Another thing is clear cutting of trees. Finding themselves suddenly in an open habitat, plants in the lower tiers of the forest experience the adverse effects of direct solar radiation. In shade-loving plants of the herbaceous and shrub layers, chlorophyll is destroyed, growth is inhibited, and some species disappear. Light-loving plants that are resistant to elevated temperatures and lack of moisture settle in the felled areas. The animal world is also changing: species associated with the tree stand disappear or migrate to other places.
Mass visits to forests by vacationers and tourists have a noticeable impact on the state of vegetation. In these cases, the harmful effect is trampling, compaction of the soil and its pollution. The direct influence of man on the animal world is the extermination of species that provide food or other material benefits to him. It is believed that since 1600, more than 160 species and subspecies of birds and at least 100 species of mammals have been exterminated by humans. The long list of extinct species includes the aurochs, a wild bull that lived throughout Europe. In the 18th century was exterminated, described by the Russian naturalist G.V. Steller's sea cow (Steller's cow) is an aquatic mammal belonging to the order Sirenidae. A little over a hundred years ago, the wild Tarpan horse, which lived in southern Russia, disappeared. Many animal species are on the verge of extinction or are preserved only in nature reserves. Such is the fate of the bison, which inhabited the prairies of North America by the tens of millions, and the bison, formerly widespread in the forests of Europe. In the Far East, sika deer have been almost completely exterminated. Intensified fishing for cetaceans has brought several species of whales to the brink of destruction: gray, bowhead, and blue.
The number of animals is also influenced by human economic activities not related to fishing. The number of Ussuri tigers has sharply decreased. This occurred as a result of the development of territories within its range and a reduction in the food supply. In the Pacific Ocean, several tens of thousands of dolphins die every year: during the fishing season, they get caught in nets and cannot get out of them. Until recently, before fishermen took special measures, the number of dolphins dying in nets reached hundreds of thousands. The effects of water pollution are very unfavorable for marine mammals. In such cases, a ban on catching animals is ineffective. For example, after the ban on catching dolphins in the Black Sea, their numbers have not recovered. The reason is that many toxic substances enter the Black Sea with river water and through straits from the Mediterranean Sea. These substances are especially harmful to baby dolphins. high mortality rate which prevents the growth of the population of these cetaceans.
The disappearance of a relatively small number of animal and plant species may not seem very significant. Each species occupies a certain place in the biocenosis, in the chain, and no one can replace it. The disappearance of one or another species leads to a decrease in the stability of biocenoses. More importantly, each species has unique properties that are unique to it. The loss of genes that determine these properties and were selected during long-term evolution deprives a person of the opportunity in the future to use them for his practical purposes (for example, for selection).
Radioactive contamination of the biosphere. The problem of radioactive contamination arose in 1945 after the explosion of atomic bombs dropped on the Japanese cities of Hiroshima and Nagasaki. Nuclear weapons tests carried out in the atmosphere before 1963 caused global radioactive contamination. When atomic bombs explode, very strong ionizing radiation is generated; radioactive particles are scattered over long distances, contaminating the soil, water bodies, and living organisms. Many radioactive isotopes have long half-lives, remaining dangerous throughout their existence. All these isotopes are included in the cycle of substances, enter living organisms and have a detrimental effect on cells.
Testing nuclear weapons (and even more so when using these weapons for military purposes) has another negative side. At nuclear explosion A huge amount of fine dust is formed, which remains in the atmosphere and absorbs a significant part of solar radiation. Calculations by scientists from around the world show that even with limited, local use of nuclear weapons, the resulting dust will block most of the solar radiation. There will be a long-term cooling (“nuclear winter”), which will inevitably lead to the death of all life on Earth.
Currently, almost any territory of the planet from the Arctic to Antarctica is subject to diverse anthropogenic influences. The consequences of the destruction of natural biocenoses and environmental pollution have become very serious. The entire biosphere is under increasing pressure from human activity, so environmental protection measures are becoming an urgent task.
Acidic atmospheric deposition on land. One of the most pressing global problems of our time and the foreseeable future is the problem of increasing acidity of atmospheric precipitation and soil cover. Areas of acidic soils do not experience droughts, but their natural fertility is reduced and unstable; They are quickly depleted and their yields are low. Acid rain not only causes acidification of surface waters and upper soil horizons. Acidity with downward flows of water spreads across the entire soil profile and causes significant acidification of groundwater. Acid rain occurs as a result of human economic activity, accompanied by the emission of colossal amounts of oxides of sulfur, nitrogen, and carbon. These oxides, entering the atmosphere, are transported over long distances, interact with water and turn into solutions of a mixture of sulfuric, sulfuric, nitrous, nitric and carbonic acids, which fall in the form of “acid rain” on land, interacting with plants, soils, and waters. The main sources in the atmosphere are the combustion of shale, oil, coal, and gas in industry, agriculture, and everyday life. Human economic activity has almost doubled the release of oxides of sulfur, nitrogen, hydrogen sulfide and carbon monoxide into the atmosphere. Naturally, this affected the increase in acidity of atmospheric precipitation, ground and ground waters. To solve this problem, it is necessary to increase the volume of systematic representative measurements of compounds of air pollutants over large areas.
