Thema: Air pollution. Plan

Thema: Air pollution.
Plan:
1. General concept of atmosphere.

2. Sources of air pollution.

3. Negative as a result of air pollution

circumstances and its consequences.

4. Atmospheric protection.


General concept of atmosphere.

The word atmosphere is derived from the Greek (atm-vapor, sphere-shell) meaning air crust and is one of the main sources of life in the biosphere. The atmosphere is a protective layer of the earth, which protects all living organisms from harmful cosmic rays, particles of meteorites falling from the sky. It retains heat on the surface of our planet. If there were no air crust, the temperature on Earth would be + 1000C during the day and -1000C in the evening. It forms clouds, rain, snow, wind, as well as moisturizes the earth, transmits sound, and is a source of vital oxygen.

The atmospheric crust is divided into the following layers.

1. Troposphere - 0-15 km above the Earth's surface

2. Stratosphere - 15-50 km each

3. Mesosphere - 50-80 km each

4. Thermosphere - 80-800 km each

5. Exosphere - above 800-1000 km.

The atmosphere is a whole shell with these layers.

The gas content of the atmosphere is almost constant: mainly nitrogen - 78.09%, oxygen - 20.95%, argon - 0.93%, carbon dioxide - 0.03%. At the same time there are more inert gases: helium, neon, xenon, hydrogen, krypton, methane, ammonia, iodine, radon gases, and in the air there are always 3-4% water vapor, dust.

The air that makes up the atmosphere has a density. As the pressure rises, the density of the gases decreases. The air shell presses on us and everything in the atmosphere with its weight. The mass of the Earth's atmosphere is 5.27. 1015 tons.

Sources of air pollution.

The physical, chemical, and biological changes that take place in the atmosphere affect living organisms. In recent years, changes in the gas balance have been observed as a result of increased human exposure. It has been found that constant changes in the amount of gases in the atmosphere can have negative consequences for our planet.

As the great thinker Abu Ali Ibn Sina said, "If there were no dust and smoke in the air, man would live up to a thousand years."

Atmospheric pollution is a change in the physical and chemical properties of air as a result of the addition of toxic compounds.

At the same time, the atmospheric air, which gives life to all living things, is now polluted mainly by two sources: natural factors and the product of human activity - anthropogenic (artificial) sources. Examples of natural factors include space dust, volcanic eruptions, rock erosion, and soil erosion, plant and animal debris, forest and steppe fires, and salt particles released into the air by sea waves. possible.

Artificial pollution of the atmosphere: motor transport takes the first place (40%), energy industry takes the second place (20%), enterprises and organizations take the third place (14%), agricultural production, household utilities, etc. account for pollution (26%).

Atmospheric air pollution is very significant in different parts of the globe, where there are many chemical plants. For example, in Japan, the United States, Europe, Russia, Tajikistan (TADAZ) and China, and in our country, such cities as Tashkent, Fergana, Chirchik, Bekabad, Navoi, Almalyk.

At present, 500 million tons of sulfur dioxide, sulfur oxides, nitrogen oxides, 6.5-7 billion tons of sulfur dioxide are released into the atmosphere every year in connection with economic activities on Earth. t. carbon dioxide is released. Aircraft also play a major role in atmospheric pollution and the consumption of large amounts of oxygen. When a single jet flies from America to Europe in 8 hours, it burns 50-100 tons of oxygen, which is released by 100,000 hectares of forest in a day, and the ozone layer is depleted within a radius of 16 km for a spacecraft to enter space.

Atmospheric air pollution also contributes to agricultural production, which is more affected by poultry and livestock complexes, meat processing plants, chemical fertilizers, harmful chemicals. In addition, dust, gases and odors from sewers, car wheels, shoes, kitchens, etc. also pollute the atmosphere. Severe air pollution has a negative impact on human health, as well as on all living things. A person breathes an average of 25 kg of air per day. Harmful dust, particles and harmful gases in the air can accumulate in the human body. As a result, it causes an increase in diseases such as skin and eye diseases, liver cirrhosis, increased bleeding, chronic bronchitis, emphysema, shortness of breath, and lung cancer. An increase in overall morbidity among children has been reported.

As a result of high levels of sulfur oxide in the air, people develop bronchitis and gastritis.

Atmospheric air pollution also harms plants and animals. The plant passes to the leaves, and through the soil and water to the root. Polluted air damages plants and disrupts their metabolism and energy. Agricultural crops and fruit trees also remain low-yielding. Harmful gases from industry and transport have a negative impact on the process of photosynthesis. Reduces transpiration up to 3 times.

It lives 300-400 years in slate fields, 120-220 years in city parks, and 40-50 years around highways.

Atmospheric pollution also affects animals, causing them to be poisoned and sometimes killed. Due to the use of chemical weapons in the wars of disease, poisoning and extinction of animal species, especially in the wars waged by the United States in Vietnam and Laos, there are now 24 bird species out of 170 bird species and 5 species out of 55 mammal species.

As a result of the release of billions of tons of SO2 into the atmosphere, the average temperature of the planet has increased by 0.5 degrees Celsius compared to 1850. If the amount of SO2 in the atmosphere continues to increase, its amount could reach 0.0379% by 2025, which is expected to raise the temperature of the planet to 1.8oS. An increase in the temperature of the Earth's atmosphere leads to the melting of glaciers, rising water levels, which reduces cropland, increases precipitation, and changes the climate.

In the last 25-30 years, acid rain has become a real environmental disaster in some countries. When any fossil fuel is burned, the exhaust gases contain sulfur and nitrogen double oxides. These compounds, which release millions of tons into the atmosphere, convert rain into acid. In recent years, large areas of forests in the United States, Canada, Germany, Sweden, Norway, Russia, and other developed countries have begun to dry up under the influence of acid rain. Such rains reduce soil fertility, destroy buildings, historical monuments, and harm human health.

Smog, a toxic fog caused by stagnant air in some areas, has a very negative impact on human health. More than 4,000 people died in a smog in London on December 5-9, 1952. Photochemical smog refers to the formation of hazardous compounds by industrial and transport exhaust gases that react under the influence of sunlight. In particular, the formation and increase in the amount of ozone, formaldehyde and other compounds are transmitted. Necessary measures must be taken immediately to reduce atmospheric air pollution on Earth.

As the American meteorologist Louis Battan said, "Either people reduce the smoke in the air, otherwise the smoke will reduce the number of people on earth."

In developed countries, environmental pollution is caused by toxins emitted by car engines. In some capitalist countries, for example: in Japan, as a result of overcrowding, a police officer controlling street traffic is forced to change his oxygen mask every 2 hours. That's why experts call cars "chemical factories on wheels." Exhaust gases from car engines contain carbon monoxide, carbon dioxide, aldehydes, nitrogen oxides, carbohydrates, lead compounds, which have a negative impact on human health, carbon monoxide binds to hemoglobin in the blood and destroys its oxygen. reduces the transport function. The lead compound is said to pass through the respiratory tract and damage people’s cardiovascular system.

Atmospheric pollution from space is caused by space dust. 10 million tons per year. space dust falls. The most dangerous are the various dusts, meteor particles, radiation streams coming from outer space to Earth. Various particles released into the atmosphere from volcanic eruptions and rock erosion can float in the air for years. For example, in 1883, a powerful volcano erupted in Karakatau, Indonesia, releasing so many dust particles into the atmosphere that it flew in the air for 5 years, covering an altitude of 8-24 km and a thickness of 16 km.

Atmospheric air pollution is one of the main environmental problems in the Republic of Uzbekistan. Ah