– discontinuous water shell of the Earth, located between the atmosphere and the solid earth's crust and representing the totality of the waters of the World Ocean and the surface waters of the land. The hydrosphere is also called the water shell of the planet. The hydrosphere covers 70% of the earth's surface. About 96% of the mass of the hydrosphere is the waters of the World Ocean, 4% is groundwater, about 2% is ice and snow (mainly Antarctica, Greenland and the Arctic), 0.4% is land surface water (rivers, lakes, swamps). A small amount of water is found in the atmosphere and living organisms. All forms of water masses pass one into another as a result of the water cycle in nature. The annual amount of precipitation falling on the earth's surface is equal to the amount of water evaporated in total from the surface of the land and oceans.

inland waters – part of the discontinuous water shell of the Earth's hydrosphere. These include: groundwater, rivers, lakes, swamps.

The groundwater- waters that are contained in the upper part of the earth's crust (up to a depth of 12-15 km).

Sources - natural outlets to the earth's surface of groundwater. The possibility of finding water in the earth's crust is determined by the porosity of the rocks. Permeable rocks (pebbles, gravel, sands) are those that pass water well. Water-resistant rocks are fine-grained, weakly or completely impervious to water (clays, granites, basalts, etc.).

Groundwater is formed as a result of seepage and accumulation of precipitation at different depths from the earth's surface. Closer to the surface are soil waters, i.e., those that take part in the formation of soils.

ground water- water above the first water-resistant horizon from the surface. Groundwater is non-pressure. Their surface level can constantly fluctuate. In dry areas, groundwater lies at great depths. In areas of excessive moisture - close to the surface.

Interstratal waters- waters located between impermeable layers.

artesian waters- pressure interstratal - usually occupy depressions where atmospheric precipitation seeps from areas where there is no upper water-resistant layer.

According to the chemical composition, groundwater can be:

1) fresh;

2) mineralized, many of which have medicinal value.

Groundwater lying near volcanic foci is often hot. Hot springs that periodically beat in the form of a fountain - geysers.

Rivers.River- a constant water stream flowing in the channel developed by him and feeding mainly on atmospheric precipitation.

Parts of the river: source - the place where the river originates. The source can be a spring, a lake, a swamp, a glacier in the mountains; mouth A place where a river flows into a sea, lake or other river. A depression in relief that extends from the source to the mouth of a river river valley. A depression in which a river constantly flows, channel.floodplain- flat, flooded during the flood bottom of the river valley. Above the floodplain, the slopes of the valley usually rise, often in a stepped form. These steps are called terraces(Fig. 10). They arise as a result of the eroding activity of the river (erosion), caused by a decrease in the erosion base.

river system a river with all its tributaries. The name of the system is given by the name of the main river.

river erosion – the deepening of the watercourse of its channel and its expansion to the sides. Erosion basis- the level to which the river deepens its valley. Its height is determined by the level of the reservoir where the river flows. The ultimate basis for the erosion of all rivers is the level of the World Ocean. With a decrease in the level of the reservoir into which the river flows, the basis of erosion decreases and the increased erosive activity of the river begins, causing the deepening of the channel.

river basin- the area from which the river with all its tributaries collects water.

Watershed – dividing line between basins of two rivers or oceans. Usually some elevated spaces serve as watersheds.

River nutrition. The flow of water into the rivers is called their nourishment. Depending on the source of incoming water, rivers are distinguished with rain, snow, glacial, underground, and when they are combined, with mixed nutrition.

The role of this or that food source depends mainly on climatic conditions. Rain feeding is characteristic of the rivers of the equatorial and most monsoon regions. In countries with a cold climate, snowmelt waters (snow nutrition) are of primary importance. In temperate latitudes, the feeding of rivers is, as a rule, mixed. Glacier-fed rivers originate in the glaciers of the highlands. The ratio between river sources can change throughout the year. So, for example, the rivers of the Ob basin can be fed by groundwater in winter, by melted snow in spring, and by underground and rainwater in summer.

What kind of food predominates depends to a large extent river regime. River regime - natural changes in the state of rivers over time, due to the physiographic properties of the basin and, first of all, climatic conditions. The regime of rivers manifests itself in the form of daily, seasonal and long-term fluctuations in the level and flow of water, ice phenomena, water temperature, the amount of sediment carried by the flow, etc. The elements of the river regime are, for example, low water - the water level in the river during the season of its lowest standing and high water- a prolonged rise in water in the river, caused by the main source of food, repeated from year to year. Depending on the presence of hydraulic structures on rivers (for example, hydroelectric power stations) that affect the regime of the river, there are regulated and natural regimes of rivers.

All the rivers of the globe are distributed among the basins of the four oceans.

The value of the rivers:

1) sources of fresh water for industry, agriculture water supply;

2) sources of electricity;

3) transport routes (including the construction of shipping channels);

4) places of catching and breeding fish; rest, etc.

Reservoirs have been built on many rivers - large artificial reservoirs. The positive consequences of their construction: create water reserves, allow you to regulate the water level in the river and prevent floods, improve transport conditions and allow you to create recreation areas. Negative consequences of the construction of reservoirs on rivers: flooding of large areas with fertile floodplain lands, groundwater rises around the reservoir, which leads to waterlogging of the lands, fish habitat conditions are disturbed, the natural process of floodplain formation is disturbed, etc. The construction of new reservoirs should be preceded by thorough scientific development.

lakes – reservoirs of slow water exchange, located in natural depressions on the land surface.

The location of lakes is influenced by the climate that determines their nutrition and regime, as well as the factors of the emergence of lake basins.

Origin lake basins can be:

1) tectonic(formed in the faults of the earth's crust, usually deep, and have banks with steep slopes - Baikal, the largest lakes in Africa and North America);

2) volcanic(in the craters of extinct volcanoes - Kronotskoye Lake in Kamchatka);

3) glacial(characteristic of areas subjected to glaciation, for example, the lakes of the Kola Peninsula);

4) karst(characteristic of areas of distribution of soluble rocks - gypsum, chalk, limestone, appear in places of failures when rocks are dissolved by groundwater);

5) dammed(they are also called dams; they arise as a result of blocking the riverbed by blocks of rocks during landslides in the mountains - Lake Sarez in the Pamirs);

6) oxbow lakes(a lake on a floodplain or a lower terrace above a floodplain is a section of a river separated from the main channel);

7) artificial(reservoirs, ponds).

Lakes are fed by atmospheric precipitation, groundwater and surface water flowing into them. According to the water regime, they distinguish sewage And drainless lakes. A river (rivers) flows out of waste lakes - Baikal, Onega, Ontario, Victoria, etc. Not a single river flows out of drainless lakes - Caspian, Dead, Chad, etc. Endorheic lakes, as a rule, are more mineralized. Depending on the degree of salinity of the water, the lakes are fresh and salty.

Origin There are two types of lake water mass:

1) lakes, the water mass of which is of atmospheric origin (such lakes prevail in number);

2) relic, or residual, - were once part of the World Ocean (Caspian Lake, etc.)

The distribution of lakes depends on the climate, and therefore the geographical distribution of lakes is to a certain extent zonal.

Lakes are of great importance: they influence the climate of the adjacent territory (humidity and thermal conditions), regulate the flow of rivers flowing from them. The economic significance of lakes: they are used as communication routes (smaller than rivers), for fishing and recreation, and water supply. Salts and healing mud are mined from the bottom of the lakes.

swamps- excessively moist land areas covered with moisture-loving vegetation and having a peat layer of at least 0.3 m. The water in the swamps is in a bound state.

Marshes are formed due to the overgrowth of lakes and the swamping of land.

lowland swamps feed on groundwater or river waters, relatively rich in salts. Consequently, vegetation settles there, which is quite demanding on food substances (sedge, horsetail, reed, green moss, birch, alder).

Raised bogs feed directly on atmospheric precipitation. They are located in watersheds. The vegetation is characterized by a limited species composition, since there is not enough mineral salts (ledum, cranberries, blueberries, sphagnum mosses, pine). Transitional swamps occupy an intermediate position. They are characterized by significant water cut and low flow. Lowland and raised bogs are two stages of the natural development of bogs. The lowland bog through the intermediate stage of the transitional bog gradually turns into a raised one.

The main reason for the formation of huge swamps is the excessive humidity of the climate, combined with a high level of groundwater due to the close occurrence of water-resistant rocks and flat relief to the surface.

The distribution of swamps also depends on the climate, which means that it is also zonal to a certain extent. Most of the swamps are in the forest zone of the temperate zone and in the tundra zone. A large amount of precipitation, low evaporation and permeability of soils, flatness, and weak dissection of interfluves contribute to swamping.

Glaciers– atmospheric water turned into ice. Glaciers are constantly moving due to their plasticity. Under the influence of gravity, the speed of their movement reaches several hundred meters per year. The movement slows down or accelerates depending on the amount of precipitation, warming or cooling of the climate, and in the mountains, the movement of glaciers is influenced by tectonic uplifts.

Glaciers form where more snow falls during the year than it has time to melt. In Antarctica and the Arctic, such conditions are created already at sea level or slightly higher. In equatorial and tropical latitudes, snow can accumulate only at high altitudes (above 4.5 km in equatorial, 5-6 km in tropical). Therefore, the height of the snow line is higher there. snow line- the boundary above which non-melting snow remains in the mountains. The height of the snow line is determined by the temperature, which is associated with the latitude of the area and the degree of continentality of its climate, the amount of solid precipitation.

The total area of ​​glaciers is 11% of the land surface with a volume of 30 million km3. If all the glaciers melted, the level of the World Ocean would rise by 66 m.

Sheet glaciers cover the earth's surface, regardless of landforms in the form of ice caps and shields, under which all the unevenness of the relief is hidden. The movement of ice in them occurs from the center of the dome to the outskirts in radial directions. The ice of these covers is of great thickness and does great destructive work on its bed: it carries detrital material, turning it into moraines. Examples of sheet glaciers are the ice of Antarctica and Greenland. Enormous blocks of ice constantly break off from the edge of these ice caps - icebergs. Icebergs can exist up to 4-10 years until they melt. In 1912, the Titanic sank from a collision with an iceberg in the Atlantic Ocean. Projects are being developed to transport icebergs to supply fresh water to arid regions of the world.

Both at modern and ancient glaciers, melted glacial waters flow out from under the glacier in a wide front, laying sandy deposits.

mountain glaciers much smaller than coverslips. In mountain glaciers the movement of ice occurs along the slope of the valley. They flow like rivers and sink below the snow line. As they move, these glaciers deepen the valleys.

Glaciers are reservoirs of fresh water created by nature. Rivers that start in glaciers are fed by their melt waters. This is especially important for arid regions.

Permafrost. By permafrost, or permafrost, one should understand the strata of frozen rocks that do not thaw for a long time - from several years to tens and hundreds of thousands of years. Water in permafrost is in a solid state, in the form of ice cement. The emergence of permafrost occurs in conditions of very low winter temperatures and low snow cover. Such conditions were in the marginal regions of the ancient ice sheets, as well as in modern conditions in Siberia, where there is little snow in winter and extremely low temperatures. The reasons for the spread of permafrost can be explained both by the legacy of the ice age and by modern harsh climatic conditions. Permafrost is nowhere as widespread as within Russia. The area of ​​continuous permafrost with a layer thickness of up to 600-800 m stands out in particular. This area has the lowest winter temperatures (for example, the Vilyui estuary).

Permafrost influences the formation of natural territorial complexes. It contributes to the development of thermokarst processes, the appearance of heaving mounds, icing, affects the magnitude and seasonal distribution of underground and surface runoff, soil and vegetation cover. In the development of minerals, the exploitation of groundwater, the construction of buildings, bridges, roads, dams, and agricultural work, it is necessary to study frozen soils.

World Ocean- all body of water. The world ocean occupies over 70% of the total surface of the Earth. The ratio between ocean and land in the northern and southern hemispheres is different. In the Northern Hemisphere, the ocean occupies 61% of the surface, in the Southern - 81%.

The world ocean is divided into four oceans - Pacific, Atlantic, Indian, Arctic.

Recently, extensive research has been carried out in the Southern Hemisphere, especially in Antarctica. As a result of these studies, scientists put forward the idea of ​​separating the Southern Ocean as an independent part of the World Ocean. The Southern Ocean, in their opinion, includes the southern parts of the Pacific, Atlantic, Indian oceans, as well as the seas surrounding Antarctica.

The size of the oceans: Pacific - 180 million km2; Atlantic - 93 million km2; Indian - 75 million km2; Arctic - 13 million km2.

The boundaries of the oceans are conditional. The basis for the division of the oceans is an independent system of currents, the distribution of salinity, temperature.

The average depth of the World Ocean is 3,700 m. The greatest depth is 11,022 m (the Mariana Trench in the Pacific Ocean).

Seas- parts of the oceans, to a greater or lesser extent separated from it by land, characterized by a special hydrological regime. Distinguish between inland and marginal seas. inland seas go deep into the interior of the mainland (Mediterranean, Baltic). marginal seas they usually adjoin the mainland on one side, and on the other, they communicate relatively freely with the ocean (Barents, Okhotsk).

gulfs- more or less significant areas of the ocean or sea that cut into the land and have a wide connection with the ocean. Small bays are called bays. Deep, winding, long bays with steep banks - fjords.

Straits- more or less narrow bodies of water that connect two neighboring oceans or seas.

The relief of the bottom of the oceans. The relief of the World Ocean has the following structure (Fig. 11). 3/4 of the area of ​​the World Ocean is occupied by depths from 3000 to 6000 m, i.e. this part of the ocean belongs to its bed.

Salinity of the World Ocean. Different salts are concentrated in ocean water: sodium chloride (gives a salty taste to water) - 78% of the total amount of salts, magnesium chloride (gives water a bitter taste) - 11%, other substances. The salinity of sea water is calculated in ppm (in the ratio of a certain amount of a substance to 1000 weight units), denoted by ‰. The salinity of the ocean is not the same, it varies from 32‰ to 38‰. The degree of salinity depends on the amount of precipitation, evaporation, as well as desalination by the waters of the rivers flowing into the sea. Salinity also changes with depth. Up to a depth of 1500 m, salinity decreases somewhat compared to the surface. Deeper, changes in water salinity are insignificant, it is almost everywhere 35‰. The minimum salinity - 5‰ - in the Baltic Sea, the maximum - up to 41‰ - in the Red Sea.

Thus, the salinity of water depends on:

1) on the ratio of precipitation and evaporation, which varies depending on the geographic latitude (because the temperature and pressure change); less salinity can be where the amount of precipitation exceeds evaporation, where there is a large influx of river waters, where ice melts;

2) from depth.

The maximum salinity of the Red Sea is due to the fact that there is a rift zone. Erupted young basaltic lavas are observed at the bottom, the formation of which indicates the rise of matter from the mantle and the expansion of the earth's crust in the Red Sea. In addition, the Red Sea is located in tropical latitudes - there is a large evaporation and a small amount of precipitation, rivers do not flow into it.

Gases are also dissolved in ocean water: nitrogen, oxygen, carbon dioxide, etc.

Marine (oceanic) currents.sea ​​currents- horizontal movement of water masses in a certain direction. Currents can be classified in many ways. Compared to the temperature of the surrounding ocean water, warm, cold and neutral currents are distinguished. Depending on the time of existence, short-term or episodic, periodic (seasonal monsoon in the Indian Ocean, tidal in the coastal parts of the oceans) and permanent currents are distinguished. Depending on the depth, surface currents (cover a layer of water on the surface), deep and bottom currents are distinguished.

Marine masses of water move due to various reasons. The main cause of sea currents is the wind, however, the movement of water can be caused by the accumulation of water in any part of the ocean, as well as the difference in water density in different parts of the ocean, and other reasons. Therefore, currents in their origin are:

1) drift - caused by constant winds (North and South trade winds, the course of the West Winds);

2) wind - caused by the action of seasonal winds (summer monsoon winds in the Indian Ocean);

3) sewage - formed due to the difference in water levels in different parts of the ocean, flowing from areas of excess water (Gulf Stream, Brazilian, East Australian);

4) compensatory - compensate (compensate) the outflow of water from different parts of the ocean (California, Peru, Benguela);

5) density (convection) - formed as a result of uneven distribution of the density of ocean water due to different temperatures and salinities (Gibraltar current);

6) tidal currents - are formed in connection with the attraction of the moon.

As a rule, sea currents exist due to a combination of several reasons.

Currents have a great influence on the climate, especially coastal areas, passing along the western or eastern coast of the continents.

Currents running along east coasts(waste), carry water from warmer equatorial latitudes to cooler ones. The air above them is warm, saturated with moisture. As you move north or south of the equator, the air cools, approaches saturation, and therefore gives precipitation to the coast, while softening the temperature.

currents passing along western coasts continents (compensatory), go from colder to warmer latitudes, the air heats up, moves away from saturation, does not give precipitation. This is one of the main reasons for the formation of deserts on the western coasts of the continents.

The course of the West Winds pronounced only in the southern hemisphere.

This is explained by the fact that there is almost no land there in temperate latitudes, water masses move freely under the influence of westerly winds of temperate latitudes. In the Northern Hemisphere, the development of a similar current is hindered by the continents.

The direction of the currents is determined by the general circulation of the atmosphere, the deflecting force of the Earth's rotation around its axis, the topography of the ocean floor, and the outlines of the continents.

Surface water temperature. Ocean water is heated by the influx of solar heat to its surface. The temperature of surface waters depends on the latitude of the place. In some areas of the ocean, this distribution is disturbed by the uneven distribution of land, ocean currents, constant winds, and runoff from the continents. Temperature naturally changes with depth. And at first the temperature drops very quickly, and then rather slowly. The average annual temperature of the surface waters of the World Ocean is +17.5 °С. At a depth of 3-4 thousand m, it usually stays in the range from +2 to 0 °C.

Ice in the oceans . The freezing point of salty ocean water is 1-2 °C lower than that of fresh water. The waters of the World Ocean are covered with ice only in the Arctic and Antarctic latitudes, where the winter is long and cold. Some shallow seas lying in the temperate zone are also covered with ice.

Distinguish between annual and multi-year ice. Ocean ice may be motionless(land-related) or floating(drift ice). In the Arctic Ocean, ice drifts and stays all year round.

In addition to the ice that forms in the ocean itself, there are ices that have broken off from glaciers descending into the ocean from the Arctic islands and the icy continent of Antarctica. Icebergs are formed - ice mountains floating in the sea. Icebergs reach a length of 2 km or more at a height of over 100 m. Icebergs of the Southern Hemisphere are especially large.

The value of the oceans. The ocean moderates the climate of the entire planet. The ocean serves as a heat accumulator. The general circulation of the atmosphere and the general circulation of the ocean are interconnected and interdependent.

The economic importance of the ocean is enormous. The wealth of the organic world of the ocean is divided into benthos- the organic world of the ocean floor, plankton- all organisms passively floating in the thickness of oceanic waters, nekton Actively swimming organisms at the bottom of the ocean. Fish account for up to 90% of all organic resources in the ocean.

Great transport value of the oceans.

The ocean is rich in energy resources. There is a tidal power plant on the coast of France. In the shelf zones of the ocean, oil and gas are being produced. Huge reserves of ferromanganese nodules are concentrated at the bottom of the ocean. Almost all chemical elements are dissolved in sea water. Salt, bromine, iodine and uranium are mined on an industrial scale.

Land in the ocean: islands- relatively small areas of land, surrounded on all sides by water.

Islands by origin are divided into:

1) mainland (parts of the mainland separated by the sea) - Madagascar, British Isles);

2) volcanic (occur during the eruption of volcanoes at the bottom of the sea; ejected products of the eruption form cones with steep slopes that rise above ocean level);

3) coral (associated with marine organisms - coral polyps; the skeletons of dead polyps form huge rocks of dense limestone, from above they are constantly built up with polyps). Coral reefs form along the coasts - underwater or slightly protruding limestone rocks above sea level. Coral islands that are not connected to the coast of the mainland are often ring-shaped with a lagoon in the middle and are called atolls. Coral islands form only in tropical latitudes, where the water is warm enough for polyps to live.

The largest island is Greenland, followed by New Guinea, Kalimantan, Madagascar. In some places there are few islands, in others they form clusters - archipelagos.

peninsulas- parts of land that protrude into the sea or lake. By origin, the peninsulas are distinguished:

1) detached, serving as a continuation of the mainland in geological terms (for example, the Balkan Peninsula);

2) attached, having nothing to do with the mainland in the geological sense (Hindostan).

The largest peninsulas: Kola, Scandinavian, Iberian, Somalia, Arabian, Asia Minor, Hindustan, Korea, Indochina, Kamchatka, Chukchi, Labrador, etc.

Atmosphere

Atmosphere- the air envelope surrounding the globe, connected with it by gravity and taking part in its daily and annual rotation.

atmospheric air consists of a mechanical mixture of gases, water vapor and impurities. The composition of air up to a height of 100 km is 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.03% carbon dioxide, and only 0.01% is accounted for by all other gases: hydrogen, helium, water vapor, ozone. The gases that make up air are constantly mixing. The percentage of gases is fairly constant. However, the content of carbon dioxide varies. Burning oil, gas, coal, reducing the number of forests leads to an increase in carbon dioxide in the atmosphere. This contributes to an increase in air temperature on Earth, since carbon dioxide passes solar energy to the Earth, and the Earth's thermal radiation delays. Thus, carbon dioxide is a kind of "insulation" of the Earth.

There is little ozone in the atmosphere. At an altitude of 25-35 km, a concentration of this gas is observed, the so-called ozone screen (ozone layer). The ozone screen performs the most important protection function - it delays the ultraviolet radiation of the Sun, which is detrimental to all life on Earth.

atmospheric water is in the air in the form of water vapor or suspended condensation products (drops, ice crystals).

Atmospheric impurities(aerosols) - liquid and solid particles located mainly in the lower layers of the atmosphere: dust, volcanic ash, soot, ice and sea salt crystals, etc. The amount of atmospheric impurities in the air increases during strong forest fires, dust storms, volcanic eruptions . The underlying surface also influences the quantity and quality of atmospheric impurities in the air. So, there is a lot of dust over the deserts, over the cities there are a lot of small solid particles, soot.

The presence of impurities in the air is associated with the content of water vapor in it, since dust, ice crystals and other particles serve as nuclei around which water vapor condenses. Like carbon dioxide, atmospheric water vapor serves as the Earth's "insulator": it delays radiation from the earth's surface.

The mass of the atmosphere is one millionth of the mass of the earth.

The structure of the atmosphere. The atmosphere has a layered structure. The layers of the atmosphere are distinguished on the basis of changes in air temperature with height and other physical properties (Table 1)

Table 1. The structure of the atmosphere and the upper boundaries Change in temperature Sphere of the atmosphere The height of the lower depending on the height

Troposphere – the lower layer of the atmosphere containing 80% air and almost all water vapor. The thickness of the troposphere varies. In tropical latitudes - 16-18 km, in temperate latitudes - 10-12 km, and in polar - 8-10 km. Everywhere in the troposphere, the air temperature drops by 0.6 °C for every 100 m of ascent (or 6 °C per 1 km). The troposphere is characterized by vertical (convection) and horizontal (wind) movement of air. All types of air masses are formed in the troposphere, cyclones and anticyclones arise, clouds, precipitation, fogs form. Weather is formed mainly in the troposphere. Therefore, the study of the troposphere is of particular importance. The lower layer of the troposphere is called surface layer, characterized by high dust content and the content of volatile microorganisms.

The transition layer from the troposphere to the stratosphere is called tropopause. It sharply increases the rarefaction of air, its temperature drops to -60 ° C over the poles to -80 ° C over the tropics. The lower air temperature over the tropics is due to powerful ascending air currents and the higher position of the troposphere.

Stratosphere The layer of the atmosphere between the troposphere and mesosphere. The gas composition of the air is similar to the troposphere, but contains much less water vapor and more ozone. At an altitude of 25 to 35 km, the highest concentration of this gas is observed (ozone screen). Up to a height of 25 km, the temperature changes little with height, and above it begins to rise. The temperature varies with latitude and time of year. Mother-of-pearl clouds are observed in the stratosphere, it is characterized by high wind speeds and jet streams of air.

The upper atmosphere is characterized by auroras and magnetic storms. Exosphere- the outer sphere from which light atmospheric gases (for example, hydrogen, helium) can flow into outer space. The atmosphere does not have a sharp upper boundary and gradually passes into outer space.

The presence of an atmosphere is of great importance for the Earth. It prevents excessive heating of the earth's surface during the day and cooling at night; protects the earth from ultraviolet radiation from the sun. A significant part of meteorites burns in the dense layers of the atmosphere.

Interacting with all the shells of the Earth, the atmosphere is involved in the redistribution of moisture and heat on the planet. It is a condition for the existence of organic life.

Solar radiation and air temperature. Air is heated and cooled by the earth's surface, which in turn is heated by the sun. The total amount of solar radiation is called solar radiation. The main part of solar radiation is scattered in the World space, only one two billionth part of solar radiation reaches the Earth. Radiation can be direct or diffuse. Solar radiation that reaches the Earth's surface in the form of direct sunlight emanating from the solar disk on a clear day is called direct radiation. Solar radiation that has undergone scattering in the atmosphere and comes to the surface of the Earth from the entire firmament is called scattered radiation. Scattered solar radiation plays a significant role in the energy balance of the Earth, being in cloudy weather, especially at high latitudes, the only source of energy in the surface layers of the atmosphere. The totality of direct and diffuse radiation entering a horizontal surface is called total radiation.

The amount of radiation depends on the duration of exposure to the surface of the sun's rays and the angle of incidence. The smaller the angle of incidence of the sun's rays, the less solar radiation the surface receives and, consequently, the air above it heats up less.

Thus, the amount of solar radiation decreases when moving from the equator to the poles, since this reduces the angle of incidence of the sun's rays and the duration of illumination of the territory in winter.

The amount of solar radiation is also affected by the cloudiness and transparency of the atmosphere.

The highest total radiation exists in tropical deserts. At the poles on the day of the solstices (at the North - on June 22, at the South - on December 22), when the Sun sets, the total solar radiation is greater than at the equator. But due to the fact that the white surface of snow and ice reflects up to 90% of the sun's rays, the amount of heat is negligible, and the surface of the earth does not heat up.

The total solar radiation entering the Earth's surface is partially reflected by it. Radiation reflected from the surface of the earth, water or clouds on which it falls is called reflected. But still, most of the radiation is absorbed by the earth's surface and turns into heat.

Since the air is heated from the surface of the earth, its temperature depends not only on the factors listed above, but also on the height above the ocean level: the higher the area, the lower the temperature (it drops by 6 ° C with every kilometer in the troposphere).

Affects the temperature and distribution of land and water, which are heated differently. Land heats up quickly and cools down quickly, water heats up slowly but retains heat longer. Thus, the air over land is warmer during the day than over water, and colder at night. This influence is reflected not only in daily, but also in seasonal features of air temperature changes. Thus, in coastal areas, under otherwise identical conditions, summers are cooler and winters are warmer.

Due to the heating and cooling of the Earth's surface day and night, in the warm and cold seasons, the air temperature changes throughout the day and year. The highest temperatures of the surface layer are observed in the desert regions of the Earth - in Libya near the city of Tripoli +58 °С, in Death Valley (USA), in Termez (Turkmenistan) - up to +55 °С. The lowest - in the interior of Antarctica - down to -89 ° C. In 1983, at the Vostok station in Antarctica, -83.6 °C was recorded - the minimum air temperature on the planet.

Air temperature- a widely used and well-studied weather characteristic .. The air temperature is measured 3-8 times a day, determining the average daily; according to the average daily, the average monthly is determined, according to the average monthly - the average annual. Temperature distributions are shown on maps. isotherms. Temperatures in July, January and annual are usually used.

Atmosphere pressure. Air, like any body, has a mass: 1 liter of air at sea level has a mass of about 1.3 g. For every square centimeter of the earth's surface, the atmosphere presses with a force of 1 kg. This average air pressure above ocean level at a latitude of 45 ° at a temperature of 0 ° C corresponds to the weight of a mercury column 760 mm high and 1 cm2 in cross section (or 1013 mb.). This pressure is taken as normal pressure.

Atmosphere pressure - the force with which the atmosphere presses on all objects in it and on the earth's surface. Pressure is determined at each point in the atmosphere by the mass of the overlying column of air with a base equal to one. With increasing altitude, atmospheric pressure decreases, because the higher the point is, the lower the height of the air column above it. As it rises, the air is rarefied and its pressure decreases. In high mountains, the pressure is much less than at sea level. This regularity is used in determining the absolute height of the area by the magnitude of the pressure.

baric stage is the vertical distance at which atmospheric pressure decreases by 1 mm Hg. Art. In the lower layers of the troposphere, up to a height of 1 km, the pressure decreases by 1 mm Hg. Art. for every 10 meters in height. The higher, the slower the pressure decreases.

In the horizontal direction at the earth's surface, the pressure varies unevenly, depending on time.

baric gradient- an indicator characterizing the change in atmospheric pressure above the earth's surface per unit distance and horizontally.

The magnitude of the pressure, in addition to the height of the terrain above sea level, depends on the air temperature. The pressure of warm air is less than that of cold air, because it expands due to heating, and contracts when cooled. As the air temperature changes, its pressure changes.

Since the change in air temperature on the globe is zonal, zoning is also characteristic of the distribution of atmospheric pressure on the earth's surface. A belt of low pressure stretches along the equator, at 30-40 ° latitudes to the north and south - belts of high pressure, at 60-70 ° latitudes the pressure is again low, and in polar latitudes - areas of high pressure. The distribution of zones of high and low pressure is associated with the peculiarities of heating and air movement near the Earth's surface. In equatorial latitudes, the air heats up well throughout the year, rises and spreads towards tropical latitudes. Approaching 30-40° latitudes, the air cools and sinks down, creating a belt of high pressure. In polar latitudes, cold air creates areas of high pressure. Cold air constantly descends, and air from temperate latitudes comes in its place. The outflow of air to the polar latitudes is the reason that a belt of low pressure is created in temperate latitudes.

Pressure belts exist all the time. They only slightly shift to the north or south, depending on the time of year (“following the Sun”). The exception is the low pressure belt of the Northern Hemisphere. It exists only in summer. Moreover, a huge area of ​​low pressure is formed over Asia with a center in tropical latitudes - the Asian Low. Its formation is explained by the fact that over a huge landmass the air is very warm. In winter, the land, which occupies significant areas in these latitudes, becomes very cold, the pressure over it increases, and areas of high pressure are formed over the continents - the Asian (Siberian) and North American (Canadian) winter atmospheric pressure maxima. Thus, in winter, the low pressure belt in the temperate latitudes of the Northern Hemisphere "breaks". It persists only over the oceans in the form of closed areas of low pressure - the Aleutian and Icelandic lows.

The influence of the distribution of land and water on the patterns of changes in atmospheric pressure is also expressed in the fact that throughout the year baric maxima exist only over the oceans: Azores (North Atlantic), North Pacific, South Atlantic, South Pacific, South Indian.

Atmospheric pressure is constantly changing. The main reason for the change in pressure is the change in air temperature.

Atmospheric pressure is measured using barometers. The aneroid barometer consists of a hermetically sealed thin-walled box, inside which the air is rarefied. When the pressure changes, the walls of the box are pressed in or protruded. These changes are transmitted to the hand, which moves on a scale graduated in millibars or millimeters.

On maps, the distribution of pressure on the Earth is shown isobars. Most often, maps indicate the distribution of isobars in January and July.

The distribution of areas and belts of atmospheric pressure significantly affects air currents, weather and climate.

Wind is the horizontal movement of air relative to the earth's surface. It occurs as a result of uneven distribution of atmospheric pressure and its movement is directed from areas with higher pressure to areas where the pressure is lower. Due to the continuous change in pressure in time and space, the speed and direction of the wind is constantly changing. The direction of the wind is determined by the part of the horizon from which it blows (the north wind blows from north to south). Wind speed is measured in meters per second. With height, the direction and strength of the wind change due to a decrease in the friction force, as well as due to a change in baric gradients. So, the reason for the occurrence of wind is the difference in pressure between different areas, and the reason for the difference in pressure is the difference in heating. Winds are affected by the deflecting force of the Earth's rotation. Winds are diverse in origin, character, and significance. The main winds are breezes, monsoons, trade winds.

Breeze– local wind (sea coasts, large lakes, reservoirs and rivers), which changes its direction twice a day: during the day it blows from the side of the reservoir to land, and at night - from land to the reservoir. Breezes arise from the fact that during the day the land heats up more than the water, which is why the warmer and lighter air above the land rises and colder air enters in its place from the side of the reservoir. At night, the air above the reservoir is warmer (because it cools more slowly), so it rises, and air masses from land move in its place - heavier, cooler (Fig. 12). Other types of local winds are foehn, bora, etc.

trade winds- constant winds in the tropical regions of the Northern and Southern Hemispheres, blowing from the high pressure zones (25-35 ° N and S) to the equator (into the low pressure belt). Under the influence of the rotation of the Earth around its axis, the trade winds deviate from their original direction. In the Northern Hemisphere, they blow from the northeast to the southwest; in the Southern Hemisphere, they blow from the southeast to the northwest. The trade winds are characterized by great stability of direction and speed. The trade winds have a great influence on the climate of the territories under their influence. This is especially evident in the distribution of precipitation.

Monsoons – winds that, depending on the seasons of the year, change direction to the opposite or close to it. In the cold season, they blow from the mainland to the ocean, and in the warm season, from the ocean to the mainland.

Monsoons are formed due to the difference in air pressure arising from the uneven heating of land and sea. In winter, the air over land is colder, over the ocean - warmer. Therefore, the pressure is higher over the mainland, lower - over the ocean. Therefore, in winter, the air moves from the mainland (area of ​​​​higher pressure) to the ocean (over which the pressure is lower). In the warm season - on the contrary: monsoons blow from the ocean to the mainland. Therefore, in the areas of monsoon distribution, precipitation usually falls in the summer.

Due to the rotation of the Earth around its axis, the monsoons deviate in the Northern Hemisphere to the right, and in the Southern Hemisphere - to the left from their original direction.

Monsoons are an important part of the general circulation of the atmosphere. Distinguish extratropical And tropical(equatorial) monsoons. In Russia, extratropical monsoons operate on the territory of the Far East coast. Tropical monsoons are more pronounced, they are most characteristic of South and Southeast Asia, where in some years several thousand mm of precipitation falls during the wet season. Their formation is explained by the fact that the equatorial low-pressure belt shifts slightly to the north or south, depending on the season (“following the Sun”). In July it is located at 15-20°N. sh. Therefore, the southeast trade wind of the Southern Hemisphere, rushing to this belt of low pressure, crosses the equator. Under the influence of the deflecting force of the rotation of the Earth (around its axis) in the Northern Hemisphere, it changes its direction and becomes southwestern. This is the summer equatorial monsoon, which carries the sea air masses of the equatorial air to a latitude of 20-28°. Encountering the Himalayas on its way, humid air leaves a significant amount of precipitation on their southern slopes. At Cherrapunja station in North India, the average annual precipitation exceeds 10,000 mm per year, and in some years even more.

From the high pressure belts, the winds also blow towards the poles, but, deviating to the east, they change their direction to the west. Therefore, in temperate latitudes, westerly winds, although they are not as constant as the trade winds.

The prevailing winds in the polar regions are northeasterly winds in the Northern Hemisphere and southeasterly winds in the Southern Hemisphere.

Cyclones and anticyclones. Due to the uneven heating of the earth's surface and the deflecting force of the Earth's rotation, huge (up to several thousand kilometers in diameter) atmospheric vortices are formed - cyclones and anticyclones (Fig. 13).

Cyclone - an ascending vortex in the atmosphere with a closed region of low pressure, in which winds blow from the periphery to the center (counterclockwise in the Northern Hemisphere, clockwise in the Southern Hemisphere). The average speed of the cyclone is 35-50 km/h, and sometimes up to 100 km/h. In a cyclone, the air rises, which affects the weather. With the onset of a cyclone, the weather changes quite dramatically: winds increase, water vapor quickly condenses, giving rise to powerful clouds, and precipitation falls.

Anticyclone- a descending atmospheric vortex with a closed area of ​​high pressure, in which winds blow from the center to the periphery (in the Northern Hemisphere - clockwise, in the Southern - counterclockwise). The speed of movement of anticyclones is 30-40 km/h, but they can linger in one place for a long time, especially on the continents. In the anticyclone, the air descends, becoming drier when warmed up, since the vapors contained in it are removed from saturation. This, as a rule, excludes the formation of clouds in the central part of the anticyclone. Therefore, during the anticyclone, the weather is clear, sunny, without precipitation. In winter - frosty, in summer - hot.

Water vapor in the atmosphere. There is always a certain amount of moisture in the atmosphere in the form of water vapor that has evaporated from the surface of the oceans, lakes, rivers, soil, etc. Evaporation depends on air temperature, wind (even a weak wind increases evaporation by a factor of 3, because all the time carries away the air saturated with water vapor and brings new portions of dry), the nature of the relief, vegetation cover, soil color.

Distinguish volatility - the amount of water that could evaporate under given conditions per unit of time, and evaporation - actually evaporated water.

In the desert, evaporation is high, and evaporation is negligible.

Air saturation. At each specific temperature, air can receive water vapor up to a known limit (until saturation). The higher the temperature, the more water the air can hold. If unsaturated air is cooled, it will gradually approach its saturation point. The temperature at which a given unsaturated air becomes saturated is called dew point. If the saturated air is cooled further, then excess water vapor will begin to thicken in it. Moisture will begin to condense, clouds will form, then precipitation will fall. Therefore, to characterize the weather, it is necessary to know relative humidity - the percentage of the amount of water vapor contained in the air to the amount that it can hold when saturated.

Absolute humidity- the amount of water vapor in grams, which is currently in 1 m3 of air.

Atmospheric precipitation and their formation. Precipitation- water in liquid or solid state that falls from clouds. clouds are the accumulations of water vapor condensation products suspended in the atmosphere - water droplets or ice crystals. Depending on the combination of temperature and degree of moisture, droplets or crystals of various shapes and sizes are formed. Small droplets float in the air, larger ones begin to fall in the form of drizzle (drizzle) or fine rain. At low temperatures, snowflakes form.

The pattern of precipitation formation is as follows: the air cools (more often when rising upwards), approaches saturation, water vapor condenses, and precipitation forms.

Precipitation is measured using a rain gauge - a cylindrical metal bucket 40 cm high and with a cross section of 500 cm2. All rainfall measurements are summed for each month, and the monthly and then the annual rainfall is displayed.

The amount of precipitation in an area depends on:

1) air temperature (affects the evaporation and moisture content of the air);

2) sea currents (over the surface of warm currents, the air heats up and is saturated with moisture; when it is transferred to neighboring, colder areas, precipitation is easily released from it. The opposite process occurs over cold currents: evaporation over them is small; when air that is not saturated with moisture enters more warm underlying surface, it expands, its saturation with moisture decreases, and precipitation does not form in it);

3) atmospheric circulation (where air moves from the sea to land, there is more precipitation);

4) the height of the place and the direction of the mountain ranges (the mountains force the air masses saturated with moisture to rise up, where, due to cooling, water vapor condenses and precipitation forms; there is more precipitation on the windward slopes of the mountains).

Precipitation is uneven. It obeys the law of zoning, that is, it changes from the equator to the poles.

In tropical and temperate latitudes, the amount of precipitation changes significantly when moving from the coasts into the depths of the continents, which depends on many factors (atmospheric circulation, the presence of ocean currents, topography, etc.).

Precipitation over most of the globe occurs unevenly throughout the year. Near the equator during the year, the amount of precipitation will change slightly, in the subequatorial latitudes there is a dry season (up to 8 months) associated with the action of tropical air masses, and a rainy season (up to 4 months) associated with the arrival of equatorial air masses. When moving from the equator to the tropics, the duration of the dry season increases, and the rainy season decreases. In subtropical latitudes, winter precipitation prevails (they are brought by moderate air masses). In temperate latitudes, precipitation falls throughout the year, but in the interior of the continents, more precipitation falls during the warm season. In polar latitudes, summer precipitation also predominates.

Weather- the physical state of the lower layer of the atmosphere in a certain area at a given moment or for a certain period of time.

Weather characteristics - air temperature and humidity, atmospheric pressure, cloudiness and precipitation, wind.

Weather is an extremely variable element of natural conditions, subject to daily and annual rhythms. The daily rhythm is due to the heating of the earth's surface by the sun's rays during the day and cooling at night. The annual rhythm is determined by the change in the angle of incidence of the sun's rays during the year.

The weather is of great importance in human economic activity. The weather is studied at meteorological stations using a variety of instruments. According to the information received at weather stations, synoptic maps are compiled. synoptic map- a weather map on which the fronts of the atmosphere and weather data at a certain moment are applied with conventional signs (air pressure, temperature, wind direction and speed, cloudiness, the position of warm and cold fronts, cyclones and anticyclones, the nature of precipitation). Synoptic maps are compiled several times a day; comparing them allows you to determine the paths of movement of cyclones, anticyclones, and atmospheric fronts.

atmospheric front- the zone of separation of air masses of different properties in the troposphere. Occurs when the masses of cold and warm air approach and meet. Its width reaches several tens of kilometers with a height of hundreds of meters and sometimes thousands of kilometers with a slight slope to the Earth's surface. The atmospheric front, passing through a certain territory, dramatically changes the weather. Among atmospheric fronts, warm and cold fronts are distinguished (Fig. 14)

warm front It is formed by the active movement of warm air towards cold air. Then warm air flows onto the receding wedge of cold air and rises along the interface plane. As it rises, it cools down. This leads to the condensation of water vapor, the emergence of cirrus and nimbostratus clouds and precipitation. With the arrival of a warm front, atmospheric pressure decreases, as a rule, warming and precipitation are associated with it.

cold front formed when cold air moves towards warm air. Cold air, being heavier, flows under warm air and pushes it up. In this case, stratocumulus rain clouds arise, from which precipitation falls in the form of showers with squalls and thunderstorms. The passage of a cold front is associated with cooling, increased winds and an increase in air transparency.

Weather forecasts are of great importance. Weather forecasts are made for different times. Usually the weather is predicted for 24-48 hours. Making long-term weather forecasts is associated with great difficulties.

Climate- the long-term weather regime characteristic of the area. The climate affects the formation of soil, vegetation, wildlife; determines the regime of rivers, lakes, marshes, influences the life of the seas and oceans, the formation of relief.

The distribution of climate on Earth is zonal. There are several climatic zones on the globe.

Climatic zones- latitudinal bands of the earth's surface, which have a uniform regime of air temperatures, due to the "norms" of the arrival of solar radiation and the formation of the same type of air masses with the features of their seasonal circulation (Table 2).

air masses- large volumes of air in the troposphere, which have more or less the same properties (temperature, humidity, dust content, etc.). The properties of air masses are determined by the territory or water area over which they form.

Characteristics of zonal air masses:

equatorial - warm and humid;

tropical - warm, dry;

temperate - less warm, more humid than tropical, seasonal differences are characteristic

arctic and antarctic - cold and dry.

Table 2.Climatic zones and the air masses operating in them

Within the main (zonal) types of VMs, there are subtypes - continental (formed over the mainland) and oceanic (formed over the ocean). An air mass is characterized by a general direction of movement, but within this volume of air there can be different winds. The properties of air masses change. Thus, marine temperate air masses, carried by western winds to the territory of Eurasia, gradually warm up (or cool down) when moving to the east, lose moisture and turn into temperate continental air.

Climate-forming factors:

1) the geographical latitude of the place, since the angle of inclination of the sun's rays depends on it, which means the amount of heat;

2) atmospheric circulation - the prevailing winds bring certain air masses;

3) ocean currents (see about atmospheric precipitation);

4) the absolute height of the place (the temperature decreases with height);

5) remoteness from the ocean - on the coasts, as a rule, less sharp temperature changes (day and night, seasons of the year); more precipitation;

6) relief (mountain ranges can trap air masses: if a moist air mass meets mountains on its way, it rises, cools, moisture condenses and precipitation falls).

Climatic zones change from the equator to the poles, as the angle of incidence of the sun's rays changes. This, in turn, determines the law of zoning, i.e., the change in the components of nature from the equator to the poles. Within the climatic zones, climatic regions are distinguished - a part of the climatic zone that has a certain type of climate. Climatic regions arise as a result of the influence of various climate-forming factors (peculiarities of atmospheric circulation, the influence of ocean currents, etc.). For example, in the temperate climate zone of the Northern Hemisphere, areas of continental, temperate continental, maritime and monsoon climates are distinguished.

General circulation of the atmosphere- a system of air currents on the globe, which contributes to the transfer of heat and moisture from one area to another. Air moves from areas of high pressure to areas of low pressure. Areas of high and low pressure are formed as a result of uneven heating of the earth's surface.

Under the influence of the rotation of the Earth, air flows deviate to the right in the Northern Hemisphere, and to the left in the Southern Hemisphere.

In the equatorial latitudes, due to high temperatures, there is constantly a low-pressure belt with weak winds. The heated air rises and spreads at a height to the north and south. At high temperatures and upward movement of air, with high humidity, large clouds form. There is a lot of rainfall here.

Approximately between 25 and 30 ° N. and yu. sh. air descends to the surface of the Earth, where, as a result, high pressure belts are formed. Near the Earth, this air is directed towards the equator (where the pressure is low), deviating to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is how trade winds are formed. In the central part of the high-pressure belts, there is a calm zone: the winds are weak. Due to the downward currents of air, the air is dried and warmed up. The hot and dry regions of the Earth are located in these belts.

In temperate latitudes with centers around 60 ° N. and yu. sh. pressure is low. The air rises and then rushes to the polar regions. In temperate latitudes, western air transport predominates (the deflecting force of the Earth's rotation acts).

The polar latitudes are characterized by low air temperatures and high pressure. The air coming from temperate latitudes descends to the Earth and again goes to temperate latitudes with northeasterly (in the Northern Hemisphere) and southeasterly (in the Southern Hemisphere) winds. Precipitation is low (Fig. 15).

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Introduction

The rapid growth of the human population and its scientific and technical equipment have radically changed the situation on Earth. If in the recent past all human activity manifested itself negatively only in limited, albeit numerous, territories, and the impact force was incomparably less than the powerful circulation of substances in nature, now the scales of natural and anthropogenic processes have become comparable, and the ratio between them continues to change with acceleration towards an increase in the power of anthropogenic influence on the biosphere.

The danger of unpredictable changes in the stable state of the biosphere, to which natural communities and species, including man himself, are historically adapted, is so great while maintaining the usual ways of managing that the current generations of people inhabiting the Earth have faced the task of urgently improving all aspects of their lives in accordance with the need preservation of the existing circulation of substances and energy in the biosphere. In addition, the widespread pollution of our environment with a variety of substances, sometimes completely alien to the normal existence of the human body, poses a serious danger to our health and the well-being of future generations.

atmosphere hydrosphere lithosphere pollution

1. Air pollution

Atmospheric air is the most important life-supporting natural environment and is a mixture of gases and aerosols of the surface layer of the atmosphere, formed during the evolution of the Earth, human activities and located outside residential, industrial and other premises. The results of environmental studies, both in Russia and abroad, unequivocally indicate that pollution of the surface atmosphere is the most powerful, constantly acting factor influencing humans, the food chain and the environment. Atmospheric air has an unlimited capacity and plays the role of the most mobile, chemically aggressive and all-penetrating agent of interaction near the surface of the components of the biosphere, hydrosphere and lithosphere.

In recent years, data have been obtained on the essential role of the ozone layer of the atmosphere for the preservation of the biosphere, which absorbs the ultraviolet radiation of the Sun, which is harmful to living organisms and forms a thermal barrier at altitudes of about 40 km, which prevents the cooling of the earth's surface.

The atmosphere has an intense impact not only on humans and biota, but also on the hydrosphere, soil and vegetation cover, geological environment, buildings, structures and other man-made objects. Therefore, the protection of atmospheric air and the ozone layer is the highest priority environmental problem and it is given close attention in all developed countries.

The polluted ground atmosphere causes lung, throat and skin cancer, central nervous system disorders, allergic and respiratory diseases, neonatal defects and many other diseases, the list of which is determined by the pollutants present in the air and their combined effects on the human body. The results of special studies carried out in Russia and abroad have shown that there is a close positive relationship between the health of the population and the quality of atmospheric air.

The main agents of the impact of the atmosphere on the hydrosphere are precipitation in the form of rain and snow, and to a lesser extent smog and fog. The surface and ground waters of the land are mainly atmospherically nourished and, as a result, their chemical composition depends mainly on the state of the atmosphere.

The negative impact of the polluted atmosphere on the soil and vegetation cover is associated both with the precipitation of acidic precipitation, which leaches calcium, humus and trace elements from the soil, and with the disruption of photosynthesis processes, leading to a slowdown in the growth and death of plants. The high sensitivity of trees (especially birch, oak) to air pollution has been identified for a long time. The combined action of both factors leads to a noticeable decrease in soil fertility and the disappearance of forests. Acid atmospheric precipitation is now considered as a powerful factor not only in the weathering of rocks and the deterioration of the quality of bearing soils, but also in the chemical destruction of man-made objects, including cultural monuments and land lines. Many economically developed countries are currently implementing programs to address the problem of acid precipitation. Through the National Acid Rainfall Evaluation Program, established in 1980, many US federal agencies began funding research into the atmospheric processes that cause acid rain to assess the effects of acid rain on ecosystems and develop appropriate conservation measures. It turned out that acid rain has a multifaceted impact on the environment and is the result of self-purification (washing) of the atmosphere. The main acidic agents are dilute sulfuric and nitric acids formed during the oxidation reactions of sulfur and nitrogen oxides with the participation of hydrogen peroxide.

Sources of air pollution

Natural sources of pollution include: volcanic eruptions, dust storms, forest fires, space dust, sea salt particles, products of plant, animal and microbiological origin. The level of such pollution is considered as background, which changes little with time.

The main natural process of pollution of the surface atmosphere is the volcanic and fluid activity of the Earth. Large volcanic eruptions lead to global and long-term pollution of the atmosphere, as evidenced by the chronicles and modern observational data (the eruption of Mount Pinatubo in the Philippines in 1991). This is due to the fact that huge amounts of gases are instantly emitted into the high layers of the atmosphere, which are picked up at high altitude by air currents moving at high speed and quickly spread throughout the globe. The duration of the polluted state of the atmosphere after large volcanic eruptions reaches several years.

Anthropogenic sources of pollution are caused by human activities. These should include:

1. Burning fossil fuels, which is accompanied by the release of 5 billion tons of carbon dioxide per year. As a result, over 100 years (1860 - 1960), the content of CO2 increased by 18% (from 0.027 to 0.032%). Over the past three decades, the rates of these emissions have increased significantly. At such rates, by the year 2000 the amount of carbon dioxide in the atmosphere will be at least 0.05%.

2. The operation of thermal power plants, when acid rain is formed during the combustion of high-sulfur coals as a result of the release of sulfur dioxide and fuel oil.

3. Exhausts of modern turbojet aircraft with nitrogen oxides and gaseous fluorocarbons from aerosols, which can damage the ozone layer of the atmosphere (ozonosphere).

4. Production activity.

5. Pollution with suspended particles (when crushing, packing and loading, from boiler houses, power plants, mine shafts, quarries when burning garbage).

6. Emissions by enterprises of various gases.

7. Combustion of fuel in flare furnaces, resulting in the formation of the most massive pollutant - carbon monoxide.

8. Fuel combustion in boilers and vehicle engines, accompanied by the formation of nitrogen oxides, which cause smog.

9. Ventilation emissions (mine shafts).

10. Ventilation emissions with excessive ozone concentration from rooms with high-energy installations (accelerators, ultraviolet sources and nuclear reactors) at MPC in working rooms of 0.1 mg/m3. In large quantities, ozone is a highly toxic gas.

During fuel combustion processes, the most intense pollution of the surface layer of the atmosphere occurs in megacities and large cities, industrial centers due to the wide distribution of vehicles, thermal power plants, boiler houses and other power plants operating on coal, fuel oil, diesel fuel, natural gas and gasoline. The contribution of vehicles to the total air pollution here reaches 40-50%. A powerful and extremely dangerous factor in atmospheric pollution are catastrophes at nuclear power plants (Chernobyl accident) and nuclear weapons tests in the atmosphere. This is due both to the rapid spread of radionuclides over long distances and to the long-term nature of the contamination of the territory.

The high danger of chemical and biochemical industries lies in the potential for accidental releases of extremely toxic substances into the atmosphere, as well as microbes and viruses that can cause epidemics among the population and animals.

Currently, many tens of thousands of pollutants of anthropogenic origin are found in the surface atmosphere. Due to the continued growth of industrial and agricultural production, new chemical compounds, including highly toxic ones, are emerging. The main anthropogenic air pollutants, in addition to large-tonnage oxides of sulfur, nitrogen, carbon, dust and soot, are complex organic, organochlorine and nitro compounds, man-made radionuclides, viruses and microbes. The most dangerous are dioxin, benz (a) pyrene, phenols, formaldehyde, and carbon disulfide, which are widespread in the air basin of Russia. Solid suspended particles are mainly represented by soot, calcite, quartz, hydromica, kaolinite, feldspar, less often sulfates, chlorides. Oxides, sulfates and sulfites, sulfides of heavy metals, as well as alloys and metals in native form were found in snow dust by specially developed methods.

In Western Europe, priority is given to 28 especially dangerous chemical elements, compounds and their groups. The group of organic substances includes acrylic, nitrile, benzene, formaldehyde, styrene, toluene, vinyl chloride, anorganic - heavy metals (As, Cd, Cr, Pb, Mn, Hg, Ni, V), gases (carbon monoxide, hydrogen sulfide, nitrogen oxides and sulfur, radon, ozone), asbestos. Lead and cadmium are predominantly toxic. Carbon disulfide, hydrogen sulfide, styrene, tetrachloroethane, toluene have an intense unpleasant odor. The impact halo of sulfur and nitrogen oxides extends over long distances. The above 28 air pollutants are included in the international registry of potentially toxic chemicals.

The main indoor air pollutants are dust and tobacco smoke, carbon monoxide and carbon dioxide, nitrogen dioxide, radon and heavy metals, insecticides, deodorants, synthetic detergents, drug aerosols, microbes and bacteria. Japanese researchers have shown that bronchial asthma may be associated with the presence of house ticks in the air of dwellings.

The atmosphere is characterized by extremely high dynamism, due to both the rapid movement of air masses in the lateral and vertical directions, and high speeds, a variety of physical and chemical reactions occurring in it. The atmosphere is now viewed as a huge "chemical cauldron" that is influenced by numerous and variable anthropogenic and natural factors. Gases and aerosols released into the atmosphere are highly reactive. Dust and soot generated during fuel combustion, forest fires absorb heavy metals and radionuclides and, when deposited on the surface, can pollute vast areas and enter the human body through the respiratory system.

The tendency of joint accumulation of lead and tin in solid suspended particles of the surface atmosphere of European Russia has been revealed; chromium, cobalt and nickel; strontium, phosphorus, scandium, rare earths and calcium; beryllium, tin, niobium, tungsten and molybdenum; lithium, beryllium and gallium; barium, zinc, manganese and copper. High concentrations of heavy metals in snow dust are due to both the presence of their mineral phases formed during the combustion of coal, fuel oil and other fuels, and the sorption of soot, clay particles of gaseous compounds such as tin halides.

The "lifetime" of gases and aerosols in the atmosphere varies in a very wide range (from 1 - 3 minutes to several months) and depends mainly on their chemical stability of size (for aerosols) and the presence of reactive components (ozone, hydrogen peroxide, etc.). .).

Estimating and even more so forecasting the state of the surface atmosphere is a very complex problem. At present, her condition is assessed mainly according to the normative approach. MPC values ​​for toxic chemicals and other standard air quality indicators are given in many reference books and guidelines. In such guidelines for Europe, in addition to the toxicity of pollutants (carcinogenic, mutagenic, allergenic and other effects), their prevalence and ability to accumulate in the human body and the food chain are taken into account. The shortcomings of the normative approach are the unreliability of the accepted MPC values ​​and other indicators due to the poor development of their empirical observational base, the lack of consideration for the combined effects of pollutants and abrupt changes in the state of the surface layer of the atmosphere in time and space. There are few stationary posts for monitoring the air basin, and they do not allow an adequate assessment of its condition in large industrial and urban centers. Needles, lichens, and mosses can be used as indicators of the chemical composition of the surface atmosphere. At the initial stage of revealing the centers of radioactive contamination associated with the Chernobyl accident, pine needles were studied, which have the ability to accumulate radionuclides in the air. Reddening of the needles of coniferous trees during periods of smog in cities is widely known.

The most sensitive and reliable indicator of the state of the surface atmosphere is the snow cover, which deposits pollutants over a relatively long period of time and makes it possible to determine the location of sources of dust and gas emissions using a set of indicators. Snowfall contains pollutants that are not captured by direct measurements or calculated data on dust and gas emissions.

One of the promising directions for assessing the state of the surface atmosphere of large industrial and urban areas is multichannel remote sensing. The advantage of this method lies in the ability to characterize large areas quickly, repeatedly and in the same way. To date, methods have been developed for estimating the content of aerosols in the atmosphere. The development of scientific and technological progress allows us to hope for the development of such methods in relation to other pollutants.

The forecast of the state of the surface atmosphere is carried out on the basis of complex data. These primarily include the results of monitoring observations, the patterns of migration and transformation of pollutants in the atmosphere, the features of anthropogenic and natural processes of pollution of the air basin of the study area, the influence of meteorological parameters, relief and other factors on the distribution of pollutants in the environment. For this purpose, heuristic models of changes in the surface atmosphere in time and space are developed for a specific region. The greatest success in solving this complex problem has been achieved for the areas where nuclear power plants are located. The end result of applying such models is a quantitative assessment of the risk of air pollution and an assessment of its acceptability from a socio-economic point of view.

Chemical pollution of the atmosphere

Atmospheric pollution should be understood as a change in its composition when impurities of natural or anthropogenic origin enter. There are three types of pollutants: gases, dust and aerosols. The latter include dispersed solid particles emitted into the atmosphere and suspended in it for a long time.

The main atmospheric pollutants include carbon dioxide, carbon monoxide, sulfur and nitrogen dioxide, as well as small gas components that can affect the temperature regime of the troposphere: nitrogen dioxide, halocarbons (freons), methane and tropospheric ozone.

The main contribution to the high level of air pollution is made by enterprises of ferrous and non-ferrous metallurgy, chemistry and petrochemistry, construction industry, energy, pulp and paper industry, and in some cities, boiler houses.

Sources of pollution - thermal power plants, which, together with smoke, emit sulfur dioxide and carbon dioxide into the air, metallurgical enterprises, especially non-ferrous metallurgy, which emit nitrogen oxides, hydrogen sulfide, chlorine, fluorine, ammonia, phosphorus compounds, particles and compounds of mercury and arsenic into the air; chemical and cement plants. Harmful gases enter the air as a result of the combustion of fuel for industrial needs, home heating, transport, combustion and processing of household and industrial waste.

Atmospheric pollutants are divided into primary, entering directly into the atmosphere, and secondary, resulting from the transformation of the latter. So, sulfur dioxide entering the atmosphere is oxidized to sulfuric anhydride, which interacts with water vapor and forms droplets of sulfuric acid. When sulfuric anhydride reacts with ammonia, ammonium sulfate crystals are formed. Similarly, as a result of chemical, photochemical, physico-chemical reactions between pollutants and atmospheric components, other secondary signs are formed. The main source of pyrogenic pollution on the planet are thermal power plants, metallurgical and chemical enterprises, boiler plants that consume more than 170% of the annually produced solid and liquid fuels.

Car emissions account for a large share of air pollution. Now about 500 million cars are operated on Earth, and by the year 2000 their number is expected to increase to 900 million. In 1997, 2400 thousand cars were operated in Moscow, with the standard of 800 thousand cars on existing roads.

Currently, road transport accounts for more than half of all harmful emissions into the environment, which are the main source of air pollution, especially in large cities. On average, with a run of 15 thousand km per year, each car burns 2 tons of fuel and about 26 - 30 tons of air, including 4.5 tons of oxygen, which is 50 times more than human needs. At the same time, the car emits into the atmosphere (kg / year): carbon monoxide - 700, nitrogen dioxide - 40, unburned hydrocarbons - 230 and solids - 2 - 5. In addition, many lead compounds are emitted due to the use of mostly leaded gasoline .

Observations have shown that in houses located near the main road (up to 10 m), residents get cancer 3-4 times more often than in houses located at a distance of 50 m from the road. Transport also poisons water bodies, soil and plants.

Toxic emissions from internal combustion engines (ICE) are exhaust and crankcase gases, fuel vapors from the carburetor and fuel tank. The main share of toxic impurities enters the atmosphere with the exhaust gases of internal combustion engines. With crankcase gases and fuel vapors, approximately 45% of hydrocarbons from their total emission enter the atmosphere.

The amount of harmful substances entering the atmosphere as part of the exhaust gases depends on the general technical condition of the vehicles and, especially, on the engine - the source of the greatest pollution. So, if the carburetor adjustment is violated, carbon monoxide emissions increase by 4 ... 5 times. The use of leaded gasoline, which has lead compounds in its composition, causes air pollution with very toxic lead compounds. About 70% of lead added to gasoline with ethyl liquid enters the atmosphere with exhaust gases in the form of compounds, of which 30% settles on the ground immediately after the cut of the car's exhaust pipe, 40% remains in the atmosphere. One medium-duty truck releases 2.5...3 kg of lead per year. The concentration of lead in the air depends on the lead content in gasoline.

It is possible to exclude the entry of highly toxic lead compounds into the atmosphere by replacing leaded gasoline with unleaded.

The exhaust gases of gas turbine engines contain such toxic components as carbon monoxide, nitrogen oxides, hydrocarbons, soot, aldehydes, etc. The content of toxic components in combustion products significantly depends on the engine operating mode. High concentrations of carbon monoxide and hydrocarbons are typical for gas turbine propulsion systems (GTPU) at reduced modes (during idling, taxiing, approaching the airport, landing approach), while the content of nitrogen oxides increases significantly when operating at modes close to nominal (takeoff , climb, flight mode).

The total emission of toxic substances into the atmosphere by aircraft with gas turbine engines is constantly growing, which is due to an increase in fuel consumption up to 20...30 t/h and a steady increase in the number of aircraft in operation. The influence of GTDU on the ozone layer and the accumulation of carbon dioxide in the atmosphere is noted.

GGDU emissions have the greatest impact on living conditions at airports and areas adjacent to test stations. Comparative data on emissions of harmful substances at airports suggest that the revenues from gas turbine engines into the surface layer of the atmosphere are, in%: carbon monoxide - 55, nitrogen oxides - 77, hydrocarbons - 93 and aerosol - 97. The rest of the emissions emit ground vehicles with internal combustion engines.

Air pollution by vehicles with rocket propulsion systems occurs mainly during their operation before launch, during takeoff, during ground tests during their production or after repair, during storage and transportation of fuel. The composition of combustion products during the operation of such engines is determined by the composition of the fuel components, the combustion temperature, and the processes of dissociation and recombination of molecules. The amount of combustion products depends on the power (thrust) of propulsion systems. During the combustion of solid fuels, water vapor, carbon dioxide, chlorine, hydrochloric acid vapor, carbon monoxide, nitrogen oxide, and Al2O3 solid particles with an average size of 0.1 microns (sometimes up to 10 microns) are emitted from the combustion chamber.

When launched, rocket engines adversely affect not only the surface layer of the atmosphere, but also outer space, destroying the Earth's ozone layer. The scale of the destruction of the ozone layer is determined by the number of launches of rocket systems and the intensity of flights of supersonic aircraft.

In connection with the development of aviation and rocket technology, as well as the intensive use of aircraft and rocket engines in other sectors of the national economy, the total emission of harmful impurities into the atmosphere has increased significantly. However, these engines still account for no more than 5% of toxic substances entering the atmosphere from vehicles of all types.

Atmospheric air is one of the main vital elements of the environment.

The Law “O6 for the Protection of Atmospheric Air” comprehensively covers the problem. He summarized the requirements developed in previous years and justified themselves in practice. For example, the introduction of rules prohibiting the commissioning of any production facilities (newly created or reconstructed) if they become sources of pollution or other negative impacts on the atmospheric air during operation. The rules on the regulation of maximum permissible concentrations of pollutants in the atmospheric air were further developed.

The state sanitary legislation only for atmospheric air established MPCs for most chemicals with isolated action and for their combinations.

Hygienic standards are a state requirement for business leaders. Their implementation should be monitored by the state sanitary supervision bodies of the Ministry of Health and the State Committee for Ecology.

Of great importance for the sanitary protection of atmospheric air is the identification of new sources of air pollution, the accounting of designed, under construction and reconstructed facilities that pollute the atmosphere, control over the development and implementation of master plans for cities, towns and industrial centers in terms of locating industrial enterprises and sanitary protection zones.

The Law "On the Protection of Atmospheric Air" provides for the requirements to establish standards for maximum permissible emissions of pollutants into the atmosphere. Such standards are established for each stationary source of pollution, for each model of vehicles and other mobile vehicles and installations. They are determined in such a way that the total harmful emissions from all sources of pollution in a given area do not exceed the MPC standards for pollutants in the air. Maximum allowable emissions are set only taking into account the maximum allowable concentrations.

The requirements of the Law relating to the use of plant protection products, mineral fertilizers and other preparations are very important. All legislative measures constitute a preventive system aimed at preventing air pollution.

The law provides not only control over the fulfillment of its requirements, but also responsibility for their violation. A special article defines the role of public organizations and citizens in the implementation of measures to protect the air environment, obliges them to actively assist state bodies in these matters, since only broad public participation will make it possible to implement the provisions of this law. Thus, it says that the state attaches great importance to the preservation of the favorable state of atmospheric air, its restoration and improvement in order to ensure the best living conditions for people - their work, life, recreation and health protection.

Enterprises or their separate buildings and structures, the technological processes of which are a source of the release of harmful and unpleasantly smelling substances into the atmospheric air, are separated from residential buildings by sanitary protection zones. The sanitary protection zone for enterprises and facilities can be increased, if necessary and properly justified, by no more than 3 times, depending on the following reasons: a) the effectiveness of the methods for cleaning emissions into the atmosphere provided or possible for implementation; b) lack of ways to clean emissions; c) placement of residential buildings, if necessary, on the leeward side in relation to the enterprise in the zone of possible air pollution; d) wind roses and other unfavorable local conditions (for example, frequent calms and fogs); e) the construction of new, still insufficiently studied, harmful in sanitary terms, industries.

Sizes of sanitary protection zones for individual groups or complexes of large enterprises in the chemical, oil refining, metallurgical, machine-building and other industries, as well as thermal power plants with emissions that create large concentrations of various harmful substances in the air and have a particularly adverse effect on health and sanitary - hygienic living conditions of the population are established in each specific case by a joint decision of the Ministry of Health and the Gosstroy of Russia.

To increase the effectiveness of sanitary protection zones, trees, shrubs and herbaceous vegetation is planted on their territory, which reduces the concentration of industrial dust and gases. In the sanitary protection zones of enterprises that intensively pollute the atmospheric air with gases harmful to vegetation, the most gas-resistant trees, shrubs and grasses should be grown, taking into account the degree of aggressiveness and concentration of industrial emissions. Particularly harmful to vegetation are emissions from chemical industries (sulphurous and sulfuric anhydride, hydrogen sulfide, sulfuric, nitric, fluoric and bromous acids, chlorine, fluorine, ammonia, etc.), ferrous and non-ferrous metallurgy, coal and thermal power industries.

2. Hydrosphere

Water has always occupied and will continue to occupy a special position among the natural resources of the Earth. This is the most important natural resource, since it is necessary, first of all, for the life of a person and every living being. Water is used by man not only in everyday life, but also in industry and agriculture.

The aquatic environment, which includes surface and groundwater, is called the hydrosphere. Surface water is mainly concentrated in the World Ocean, which contains about 91% of all water on Earth. The water in the ocean (94%) and underground is salty. The amount of fresh water is 6% of the total water on Earth, and a very small proportion of it is available in places that are easily accessible for extraction. Most of the fresh water is contained in snow, freshwater icebergs and glaciers (1.7%), located mainly in the regions of the southern polar circle, as well as deep underground (4%).

Currently, humanity uses 3.8 thousand cubic meters. km. water annually, and consumption can be increased to a maximum of 12 thousand cubic meters. km. At the current rate of growth in water consumption, this will be enough for the next 25-30 years. The pumping of groundwater leads to subsidence of soil and buildings and a decrease in groundwater levels by tens of meters.

Water is of great importance in industrial and agricultural production. It is well known that it is necessary for the everyday needs of man, all plants and animals. For many living beings, it serves as a habitat.

The growth of cities, the rapid development of industry, the intensification of agriculture, the significant expansion of irrigated land, the improvement of cultural and living conditions, and a number of other factors are increasingly complicating the problem of water supply.

Each inhabitant of the Earth on average consumes 650 cubic meters. m of water per year (1780 liters per day). However, to meet physiological needs, 2.5 liters per day is enough, i.e. about 1 cu. m per year. A large amount of water is required for agriculture (69%) mainly for irrigation; 23% of water is consumed by industry; 6% is spent in everyday life.

Taking into account the needs of water for industry and agriculture, water consumption in our country is from 125 to 350 liters per day per person (in St. Petersburg 450 liters, in Moscow - 400 liters).

In developed countries, each inhabitant has 200-300 liters of water per day. At the same time, 60% of the land does not have enough fresh water. A quarter of humanity (approximately 1.5 million people) lack it, and another 500 million suffer from lack and poor quality of drinking water, which leads to intestinal diseases.

Most of the water after its use for household needs is returned to the rivers in the form of wastewater.

Purpose of the work: to consider the main sources and types of pollution of the Hydrosphere, as well as methods of wastewater treatment.

Fresh water scarcity is already becoming a global problem. The ever-increasing needs of industry and agriculture for water are forcing all countries, scientists of the world to look for various means to solve this problem.

At the present stage, the following areas of rational use of water resources are determined: more complete use and expanded reproduction of fresh water resources; development of new technological processes to prevent pollution of water bodies and minimize the consumption of fresh water.

The structure of the Earth's hydrosphere

The hydrosphere is the water shell of the Earth. It includes: surface and groundwater, directly or indirectly providing the vital activity of living organisms, as well as water falling in the form of precipitation. Water occupies the predominant part of the biosphere. Of the 510 million km2 of the total area of ​​the earth's surface, the World Ocean accounts for 361 million km2 (71%). The ocean is the main receiver and accumulator of solar energy, since water has a high thermal conductivity. The main physical properties of an aqueous medium are its density (800 times higher than air density) and viscosity (55 times higher than air). In addition, water is characterized by mobility in space, which helps to maintain the relative homogeneity of physical and chemical characteristics. Water bodies are characterized by temperature stratification, i.e. change in water temperature with depth. The temperature regime has significant daily, seasonal, annual fluctuations, but in general, the dynamics of water temperature fluctuations is less than that of air. The light regime of water under the surface is determined by its transparency (turbidity). The photosynthesis of bacteria, phytoplankton, and higher plants depends on these properties, and, consequently, the accumulation of organic matter, which is possible only within the euphonic zone, i.e. in the layer where the processes of synthesis prevail over the processes of respiration. Turbidity and transparency depend on the content of suspended substances of organic and mineral origin in water. Of the most significant abiotic factors for living organisms in water bodies, it should be noted the salinity of water - the content of dissolved carbonates, sulfates, and chlorides in it. There are few of them in fresh waters, and carbonates predominate (up to 80%). In ocean water, chlorides and, to some extent, sulfates predominate. Almost all elements of the periodic system, including metals, are dissolved in sea water. Another characteristic of the chemical properties of water is associated with the presence of dissolved oxygen and carbon dioxide in it. Oxygen, which goes to the respiration of aquatic organisms, is especially important. The vital activity and distribution of organisms in water depend on the concentration of hydrogen ions (pH). All the inhabitants of the water - hydrobionts have adapted to a certain level of pH: some prefer an acidic, others - alkaline, and others - a neutral environment. A change in these characteristics, primarily as a result of industrial impact, leads to the death of aquatic organisms or to the replacement of some species by others.

The main types of pollution of the hydrosphere.

Pollution of water resources is understood as any changes in the physical, chemical and biological properties of water in reservoirs due to the discharge of liquid, solid and gaseous substances into them, which cause or may create inconvenience, making the water of these reservoirs dangerous for use, causing damage to the national economy, health and public safety. Sources of pollution are objects from which discharges or otherwise enter water bodies of harmful substances that degrade the quality of surface waters, limit their use, and also negatively affect the state of the bottom and coastal water bodies.

The main sources of pollution and clogging of water bodies are insufficiently treated wastewater from industrial and municipal enterprises, large livestock complexes, production waste from the development of ore minerals; water mines, mines, processing and alloying of timber; water and rail transport discharges; flax primary processing waste, pesticides, etc. Pollutants, getting into natural water bodies, lead to qualitative changes in water, which are mainly manifested in a change in the physical properties of water, in particular, the appearance of unpleasant odors, tastes, etc.); in changing the chemical composition of water, in particular, the appearance of harmful substances in it, the presence of floating substances on the surface of the water and their deposition at the bottom of reservoirs.

Phenol is a rather harmful pollutant of industrial waters. It is found in the wastewater of many petrochemical plants. At the same time, the biological processes of reservoirs, the process of their self-purification, are sharply reduced, the water acquires a specific smell of carbolic acid.

The life of the population of reservoirs is adversely affected by wastewater from the pulp and paper industry. Oxidation of wood pulp is accompanied by the absorption of a significant amount of oxygen, which leads to the death of eggs, fry and adult fish. Fibers and other insoluble substances clog water and impair its physical and chemical properties. From rotting wood and bark, various tannins are released into the water. Resin and other extractive products decompose and absorb a lot of oxygen, causing the death of fish, especially juveniles and eggs. In addition, mole alloys heavily clog rivers, and driftwood often completely clogs their bottom, depriving fish of spawning grounds and food places.

Oil and oil products at the present stage are the main pollutants of inland waters, waters and seas, the World Ocean. Getting into water bodies, they create various forms of pollution: an oil film floating on the water, oil products dissolved or emulsified in water, heavy fractions that have settled to the bottom, etc. This hinders the processes of photosynthesis in water due to the cessation of access to sunlight, and also causes the death of plants and animals. At the same time, the smell, taste, color, surface tension, viscosity of water change, the amount of oxygen decreases, harmful organic substances appear, water acquires toxic properties and poses a threat not only to humans. 12 g of oil makes a ton of water unfit for consumption. Each ton of oil creates an oil film on an area of ​​up to 12 square meters. km. Restoration of affected ecosystems takes 10-15 years.

Nuclear power plants pollute rivers with radioactive waste. Radioactive substances are concentrated by the smallest planktonic microorganisms and fish, then they are transferred along the food chain to other animals. It has been established that the radioactivity of planktonic inhabitants is thousands of times higher than the water in which they live.

Wastewater with increased radioactivity (100 curies per 1 liter or more) is subject to disposal in underground drainless pools and special tanks.

Population growth, the expansion of old and the emergence of new cities have significantly increased the flow of domestic wastewater into inland waters. These effluents have become a source of pollution of rivers and lakes with pathogenic bacteria and helminths. Synthetic detergents widely used in everyday life pollute water bodies to an even greater extent. They are also widely used in industry and agriculture. The chemicals contained in them, entering rivers and lakes with sewage, have a significant impact on the biological and physical regime of water bodies. As a result, the ability of water to saturate with oxygen decreases, and the activity of bacteria that mineralize organic substances is paralyzed.

The pollution of water bodies with pesticides and mineral fertilizers, which come from the fields along with jets of rain and melt water, causes serious concern. As a result of research, for example, it has been proven that insecticides contained in water in the form of suspensions dissolve in oil products that pollute rivers and lakes. This interaction leads to a significant weakening of the oxidative functions of aquatic plants. Getting into water bodies, pesticides accumulate in plankton, benthos, fish, and through the food chain they enter the human body, affecting both individual organs and the body as a whole.

In connection with the intensification of animal husbandry, the effluents of enterprises in this branch of agriculture are increasingly making themselves felt.

Wastewater containing vegetable fibers, animal and vegetable fats, fecal matter, fruit and vegetable residues, waste from the leather and pulp and paper industries, sugar and breweries, meat and dairy, canning and confectionery industries are the cause of organic pollution of water bodies.

In wastewater, there are usually about 60% of substances of organic origin, biological (bacteria, viruses, fungi, algae) pollution in municipal, medical and sanitary waters and waste from leather and wool washing enterprises belong to the same organic category.

A serious environmental problem is that the usual way of using water to absorb heat in thermal power plants is to directly pump fresh lake or river water through a cooler and then return it to natural reservoirs without pre-cooling. A 1000 MW power plant requires a lake with an area of ​​810 hectares and a depth of about 8.7 m.

Power plants can raise the temperature of the water by 5-15 C compared to the environment. Under natural conditions, with slow increases or decreases in temperature, fish and other aquatic organisms gradually adapt to changes in ambient temperature. But if, as a result of the discharge of hot effluents from industrial enterprises into rivers and lakes, a new temperature regime is quickly established, there is not enough time for acclimatization, living organisms receive heat shock and die.

Heat shock is the extreme result of thermal pollution. The discharge of heated effluents into water bodies can have other, more insidious consequences. One of them is the effect on metabolic processes.

As a result of an increase in water temperature, the oxygen content in it decreases, while the need for it by living organisms increases. The increased need for oxygen, its lack cause severe physiological stress and even death. Artificial heating of water can significantly change the behavior of fish - cause untimely spawning, disrupt migration

An increase in water temperature can disrupt the structure of the flora of reservoirs. The algae characteristic of cold water are replaced by more thermophilic ones and, finally, at high temperatures they are completely replaced by them, while favorable conditions arise for the mass development of blue-green algae in reservoirs - the so-called “water bloom”. All of the above consequences of thermal pollution of water bodies cause great harm to natural ecosystems and lead to a detrimental change in the human environment. Damage resulting from thermal pollution can be divided into: - economic (losses due to a decrease in the productivity of water bodies, the cost of eliminating the consequences of pollution); social (aesthetic damage from landscape degradation); environmental (irreversible destruction of unique ecosystems, extinction of species, genetic damage).

The path that will allow people to avoid the ecological impasse is now clear. These are non-waste and low-waste technologies, the transformation of waste into useful resources. But it will take decades to bring the idea to life.

Wastewater Treatment Methods

Wastewater treatment is the treatment of wastewater to destroy or remove harmful substances from it. Cleaning methods can be divided into mechanical, chemical, physico-chemical and biological.

The essence of the mechanical method

purification consists in the fact that existing impurities are removed from wastewater by settling and filtering. Mechanical treatment allows you to isolate up to 60-75% of insoluble impurities from domestic wastewater, and up to 95% from industrial wastewater, many of which (as valuable materials) are used in production.

The chemical method consists in the fact that various chemical reagents are added to the wastewater, which react with pollutants and precipitate them in the form of insoluble precipitates. Chemical cleaning achieves a reduction of insoluble impurities up to 95% and soluble impurities up to 25%.

With the physicochemical method

Treatment of wastewater removes finely dispersed and dissolved inorganic impurities and destroys organic and poorly oxidized substances. Of the physicochemical methods, coagulation, oxidation, sorption, extraction, etc., as well as electrolysis, are most often used. Electrolysis is the destruction of organic matter in wastewater and the extraction of metals, acids and other inorganic substances by the flow of electric current. Wastewater treatment using electrolysis is effective in lead and copper plants, in the paint and varnish industry.

Wastewater is also treated using ultrasound, ozone, ion exchange resins and high pressure. Cleaning by chlorination has proven itself well.

Among the wastewater treatment methods, a biological method based on the use of the laws of biochemical self-purification of rivers and other water bodies should play an important role. Various types of biological devices are used: biofilters, biological ponds, etc. In biofilters, wastewater is passed through a layer of coarse-grained material covered with a thin bacterial film. Thanks to this film, the processes of biological oxidation proceed intensively.

In biological ponds, all organisms inhabiting the reservoir take part in wastewater treatment. Before biological treatment, wastewater is subjected to mechanical treatment, and after biological (to remove pathogenic bacteria) and chemical treatment, chlorination with liquid chlorine or bleach. For disinfection, other physical and chemical methods are also used (ultrasound, electrolysis, ozonation, etc.). The biological method gives the best results in the treatment of municipal waste, as well as waste from oil refineries, the pulp and paper industry, and the production of artificial fiber.

In order to reduce pollution of the hydrosphere, it is desirable to reuse in closed, resource-saving, waste-free processes in industry, drip irrigation in agriculture, and economical use of water in production and at home.

3. Lithosphere

The period from 1950 to the present is called the period of the scientific and technological revolution. By the end of the 20th century, there were huge changes in technology, new means of communication and information technologies appeared, which dramatically changed the possibilities for exchanging information and brought the most remote points of the planet closer together. The world is literally changing rapidly before our eyes, and humanity in its actions does not always keep up with these changes.

Environmental problems did not arise on their own. This is the result of the natural development of civilization, in which the previously formulated rules of human behavior in their relationships with the environment and within human society, which supported a sustainable existence, came into conflict with the new conditions created by scientific and technological progress. In the new conditions, it is necessary to form both new rules of conduct and a new morality, taking into account all natural science knowledge. The greatest difficulty, which determines much in solving environmental problems, is still the insufficient concern of human society as a whole and of many of its leaders with the problems of preserving the environment.

Lithosphere, its structure

Man exists in a certain space, and the main component of this space is the earth's surface - the surface of the lithosphere.

The lithosphere is called the solid shell of the Earth, consisting of the earth's crust and the layer of the upper mantle underlying the earth's crust. The distance of the lower boundary of the Earth's crust from the Earth's surface varies within 5-70 km, and the Earth's mantle reaches a depth of 2900 km. After it, at a distance of 6371 km from the surface, there is a core.

Land occupies 29.2% of the surface of the globe. The upper layers of the lithosphere is called soil. The soil cover is the most important natural formation and component of the Earth's biosphere. It is the soil shell that determines many processes occurring in the biosphere.

Soil is the main source of food, providing 95-97% of food resources for the world's population. The area of ​​land resources in the world is 129 million square meters. km, or 86.5% of the land area. Arable land and perennial plantations in the composition of agricultural land occupy about 10% of the land, meadows and pastures - 25% of the land. Soil fertility and climatic conditions determine the possibility of the existence and development of ecological systems on Earth. Unfortunately, due to improper exploitation, some of the fertile land is lost every year. Thus, over the past century, as a result of accelerated erosion, 2 billion hectares of fertile land have been lost, which is 27% of the total area of ​​land used for agriculture.

Sources of soil pollution.

The lithosphere is polluted by liquid and solid pollutants and wastes. It has been established that annually one ton of waste is generated per inhabitant of the Earth, including more than 50 kg of polymeric, difficult to decompose.

Sources of soil pollution can be classified as follows.

Residential buildings and public utilities. The composition of pollutants in this category of sources is dominated by household waste, food waste, construction waste, waste from heating systems, worn-out household items, etc. All this is collected and taken to landfills. For large cities, the collection and destruction of household waste in landfills has become an intractable problem. The simple burning of garbage in city dumps is accompanied by the release of toxic substances. When burning such objects, for example, chlorine-containing polymers, highly toxic substances are formed - dioxides. Despite this, in recent years, methods have been developed for the destruction of household waste by incineration. A promising method is the burning of such debris over hot melts of metals.

Industrial enterprises. Solid and liquid industrial waste constantly contains substances that can have a toxic effect on living organisms and plants. For example, non-ferrous heavy metal salts are usually present in waste from the metallurgical industry. The engineering industry releases cyanides, arsenic and beryllium compounds into the environment; in the production of plastics and artificial fibers, wastes containing phenol, benzene, styrene are formed; in the production of synthetic rubbers, catalyst wastes, substandard polymer clots get into the soil; in the production of rubber products, dust-like ingredients, soot, which settle on the soil and plants, waste rubber-textile and rubber parts, are released into the environment, and during the operation of tires, worn-out and failed tires, inner tubes and rim tapes. The storage and disposal of used tires is currently an unresolved problem, as it often causes large fires that are very difficult to extinguish. The degree of utilization of used tires does not exceed 30% of their total volume.

Transport. During the operation of internal combustion engines, nitrogen oxides, lead, hydrocarbons, carbon monoxide, soot and other substances are intensively released, deposited on the surface of the earth or absorbed by plants. In the latter case, these substances also enter the soil and are involved in the cycle associated with food chains.

Agriculture. Soil pollution in agriculture occurs due to the introduction of huge amounts of mineral fertilizers and pesticides. Some pesticides are known to contain mercury.

Soil contamination with heavy metals. Heavy metals are non-ferrous metals whose density is greater than that of iron. These include lead, copper, zinc, nickel, cadmium, cobalt, chromium, mercury.

A feature of heavy metals is that in small quantities, almost all of them are necessary for plants and living organisms. In the human body, heavy metals are involved in vital biochemical processes. However, exceeding the allowable amount leads to serious diseases.

...

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In order to determine the basic properties of the biosphere, we must first understand what we are dealing with. What is the form of its organization and existence? How does it work and interact with the outside world? Ultimately, what is it?

From the appearance of the term at the end of the 19th century to the creation of a holistic doctrine by the biogeochemist and philosopher V.I. Vernadsky, the definition of the concept of "biosphere" has undergone significant changes. It has moved from the category of a place or territory where living organisms live to the category of a system consisting of elements or parts, functioning according to certain rules to achieve a specific goal. It is on how to consider the biosphere that it depends on what properties are inherent in it.

The term is based on ancient Greek words: βιος - life and σφαρα - sphere or ball. That is, it is some shell of the Earth, where there is life. Earth, as an independent planet, according to scientists, arose about 4.5 billion years ago, and a billion years later life appeared on it.

Archean, Proterozoic and Phanerozoic eon. Eons are made up of eras. The latter consists of the Paleozoic, Mesozoic and Cenozoic. Eras from periods. Cenozoic from the Paleogene and Neogene. Periods from epochs. The current - Holocene - began 11.7 thousand years ago.

Borders and layers of propagation

The biosphere has a vertical and horizontal distribution. Vertically, it is conventionally divided into three layers where life exists. These are the lithosphere, hydrosphere and atmosphere. The lower boundary of the lithosphere reaches 7.5 km from the Earth's surface. The hydrosphere is located between the lithosphere and the atmosphere. Its maximum depth is 11 km. The atmosphere covers the planet from above and life in it exists, presumably, at an altitude of up to 20 km.

In addition to vertical layers, the biosphere has a horizontal division or zoning. This is a change in the natural environment from the Earth's equator to its poles. The planet has the shape of a ball and therefore the amount of light and heat entering its surface is different. The largest zones are geographical zones. Starting from the equator, it goes first equatorial, above tropical, then temperate, and finally, near the poles - arctic or antarctic. Inside the belts are natural zones: forests, steppes, deserts, tundras, and so on. These zones are characteristic not only for land, but also for the oceans. The horizontal location of the biosphere has its own altitude. It is determined by the surface structure of the lithosphere and differs from the foot of the mountain to its top.

To date, the flora and fauna of our planet has about 3,000,000 species, and this is only 5% of the total number of species that have managed to "live" on Earth. About 1.5 million animal species and 0.5 million plant species have found their description in science. There are not only undescribed species, but also unexplored regions of the Earth, the species content of which is unknown.

Thus, the biosphere has a temporal and spatial characteristic, and the species composition of living organisms that fills it varies both in time and in space - vertically and horizontally. This led scientists to the conclusion that the biosphere is not a planar structure and has signs of temporal and spatial variability. It remains to determine, under the influence of what external factor, it changes in time, space and structure. That factor is solar energy.

If we accept that the species of all living organisms, regardless of the spatial and temporal framework, are parts, and their totality is the whole, then their interaction with each other and with the external environment is a system. L von Bertalanffy and F.I. Peregudov, defining a system, argued that it is a complex of interacting components, or a set of elements that are in relationship with each other and with the environment, or a set of interconnected elements that are isolated from the environment and interact with it as a whole.

System

The biosphere as a single integral system can be conditionally divided into its constituent parts. The most common such division is species. Each type of animal or plant is taken as an integral part of the system. It can also be recognized as a system, with its own structure and composition. But the species does not exist in isolation. Its representatives live in a certain territory, where they interact not only with each other and the environment, but also with other species. Such a residence of species, in one area, is called an ecosystem. The smallest ecosystem, in turn, is included in the larger one. That in even more and so to the global - to the biosphere. Thus, the biosphere, as a system, can be considered as consisting of parts, which are either species or biospheres. The only difference is that a species can be identified because it has features that distinguish it from others. It is independent and in other types - parts are not included. With biospheres, such a distinction is impossible - one part of the other.

signs

The system has two more significant features. It was created to achieve a specific goal and the functioning of the whole system is more effective than each of its parts separately.

Thus, the properties as a system, in its integrity, synergy and hierarchy. Integrity lies in the fact that the connections between its parts or internal connections are much stronger than with the environment or external ones. Synergy or systemic effect is that the capabilities of the entire system are much greater than the sum of the capabilities of its parts. And, although each element of the system is a system itself, nevertheless, it is only a part of the general and larger one. This is its hierarchy.

The biosphere is a dynamic system that changes its state under external influence. It is open because it exchanges matter and energy with the environment. It has a complex structure, as it consists of subsystems. And finally, it is a natural system - formed as a result of natural changes over many years.

Thanks to these qualities, she can regulate and organize herself. These are the basic properties of the biosphere.

In the middle of the 20th century, the concept of self-regulation was first used by the American physiologist Walter Cannon, and the English psychiatrist and cybernetician William Ross Ashby introduced the term self-organization and formulated the law of required diversity. This cybernetic law formally proved the need for a large species diversity for the stability of the system. The greater the diversity, the higher the probability of the system to maintain its dynamic stability in the face of large external influences.

Properties

Responding to external influence, resisting and overcoming it, reproducing itself and restoring, that is, maintaining its internal constancy, such is the goal of a system called the biosphere. These qualities of the whole system are built on the ability of its part, which is the species, to maintain a certain number or homeostasis, as well as each individual or living organism to maintain its physiological conditions - homeostasis.

As you can see, these properties developed in her under the influence and to counteract external factors.

The main external factor is solar energy. If the number of chemical elements and compounds is limited, then the energy of the Sun is constantly supplied. Thanks to it, the migration of elements along the food chain from one living organism to another and the transformation from an inorganic state to an organic one and vice versa takes place. Energy accelerates the course of these processes inside living organisms and, in terms of the reaction rate, they occur much faster than in the external environment. The amount of energy stimulates the growth, reproduction and increase in the number of species. Diversity, in turn, provides an opportunity for additional resistance to external influences, since there is a possibility of duplication, hedging or replacement of species in the food chain. The migration of elements will thus be additionally ensured.

Human influence

The only part of the biosphere that is not interested in increasing the species diversity of the system is man. He strives in every possible way to simplify ecosystems, because in this way he can more effectively monitor and regulate it, depending on his needs. Therefore, all biosystems artificially created by man or the degree of his influence, on which is significant, are very scarce in terms of species. And their stability and ability to self-healing and self-regulation tends to zero.

With the advent of the first living organisms, they began to change the conditions of existence on Earth to suit their needs. With the advent of man, he already began to change the biosphere of the planet so that his life was as comfortable as possible. It is comfortable, because we are not talking about survival or saving life. Following logic, something should appear that will change the person himself for its own purposes. I wonder what it will be?

Video - Biosphere and noosphere

5. Agroecosystems. Comparison with natural ecosystems.

6. The main types of anthropogenic impacts on the biosphere. Their strengthening in the second half of the 20th century.

7. Natural hazards. Their impact on ecosystems.

8. Modern environmental problems and their significance.

9. Environmental pollution. Classification.

11. Greenhouse effect. Ecological functions of ozone. Ozone destruction reactions.

12. Help. Photochemical smog reactions.

13. Acid precipitation. Their effect on ecosystems.

14. Climate. Modern climate models.

16. Anthropogenic impact on groundwater.

17. Ecological consequences of water pollution.

19. Ecological and hygienic regulation of the quality of the environment.

20. Sanitary - hygienic standards for environmental quality. summation effect.

21. Control of physical influences: radiation, noise, vibration, emi.

22. Rationing of chemicals in food.

23. Industrial and economic and complex environmental quality standards. Pdv, pds, pdn, szz. Ecological capacity of the territory.

24. Some shortcomings of the system of normalized indicators. Some shortcomings of the environmental regulation system.

25. Environmental monitoring. Types (by scale, objects, methods of observation), monitoring tasks.

26. Gsmos, egsem and their tasks.

27. Ecotoxicological monitoring. Toxicants. The mechanism of their action on the body.

28. Toxic effect of some inorganic superoxidants.

29. Toxic effect of some organic superoxidants.

30. Biotesting, bioindication and bioaccumulation in the environmental monitoring system.

Prospects for the use of bioindicators.

31. Risk. Classification and general characteristics of risks.

Risk. General characteristics of risks.

Types of risks.

32. Environmental risk factors. The situation in the Perm region, in Russia.

33. The concept of zero risk. Acceptable risk. Risk perception by different categories of citizens.

34. Environmental risk assessment for man-made systems, natural disasters, natural ecosystems. Stages of risk assessment.

35. Analysis, environmental risk management.

36. Environmental risk to human health.

37. The main directions of engineering protection of ops from man-caused impacts. The role of biotechnology in the protection of ops.

38. Basic principles for creating resource-saving industries.

39. Protection of the atmosphere from man-made impacts. Purification of gas emissions from aerosols.

40. Purification of gas emissions from gaseous and vaporous impurities.

41. Wastewater treatment from insoluble and soluble impurities.

42. Neutralization and disposal of solid waste.

2. Natural environment as a system. Atmosphere, hydrosphere, lithosphere. Composition, role in the biosphere.

A system is understood as a certain conceivable or real set of parts with connections between them.

natural environment- that system whole, consisting of various functionally connected and hierarchically subordinated ecosystems, united in the biosphere. Within this system, there is a global exchange of matter and energy between all its components. This exchange is realized by changing the physical and chemical properties of the atmosphere, hydrosphere, lithosphere. Any ecosystem is based on the unity of living and non-living matter, which manifests itself in the use of elements of inanimate nature, from which, thanks to solar energy, organic substances are synthesized. Simultaneously with the process of their creation, the process of consumption and decomposition into initial inorganic compounds takes place, which ensures the external and internal circulation of substances and energy. This mechanism operates in all the main components of the biosphere, which is the main condition for the sustainable development of any ecosystem. The natural environment as a system develops due to this interaction, therefore, the isolated development of the components of the natural environment is impossible. But the various components of the natural environment have different, inherent features only to them, which allows them to be identified and studied separately.

Atmosphere.

This is the gaseous shell of the Earth, consisting of a mixture of various gases, vapors and dust. It has a clearly defined layered structure. The layer closest to the Earth's surface is called the troposphere (height from 8 to 18 km). Further, at an altitude of up to 40 km, there is a layer of the stratosphere, and at an altitude of more than 50 km, the mesosphere, above which the thermosphere is located, which does not have a definite upper boundary.

The composition of the Earth's atmosphere: nitrogen 78%, oxygen 21%, argon 0.9%, water vapor 0.2 - 2.6%, carbon dioxide 0.034%, neon, helium, nitrogen oxides, ozone, krypton, methane, hydrogen.

Ecological functions of the atmosphere:

Protective function (against meteorites, cosmic radiation).

Thermoregulatory (in the atmosphere there is carbon dioxide, water, which increase the temperature of the atmosphere). The average temperature on earth is 15 degrees, if there were no carbon dioxide and water, the temperature on earth would be 30 degrees lower.

Weather and climate are formed in the atmosphere.

The atmosphere is a habitat, because it has life-sustaining functions.

the atmosphere weakly absorbs weak short-wave radiation, but delays long-wave (IR) thermal radiation of the earth's surface, which reduces the heat transfer of the Earth and increases its temperature;

The atmosphere has a number of features inherent only to it: high mobility, variability of its constituent components, originality of molecular reactions.

Hydrosphere.

This is the water shell of the Earth. It is a collection of oceans, seas, lakes, rivers, ponds, swamps, groundwater, glaciers and atmospheric water vapor.

The role of water:

is a component of living organisms; living organisms cannot do without water for a long time;

affects the composition in the surface layer of the atmosphere - supplies oxygen to it, regulates the content of carbon dioxide;

affects the climate: water has a high heat capacity, therefore, heating up during the day, it cools down more slowly at night, which makes the climate milder and more humid;

chemical reactions take place in the water, which ensure the chemical purification of the biosphere and the production of biomass;

The water cycle links together all parts of the biosphere, forming a closed system. As a result of it, the accumulation, purification and redistribution of the planetary water supply occurs;

Evaporating water from the earth's surface forms atmospheric water in the form of water vapor (greenhouse gas).

Lithosphere.

This is the upper solid shell of the Earth, includes the earth's crust and the upper mantle of the Earth. The thickness of the lithosphere is from 5 to 200 km. The lithosphere is characterized by area, relief, soil cover, vegetation, subsoil and space for human economic activity.

The lithosphere consists of two parts: the parent rock and the soil cover. The soil cover has a unique property - fertility, i.e. the ability to provide plant nutrition and their biological productivity. This determines the indispensability of the soil in agricultural production. The soil cover of the Earth is a complex environment containing solid (mineral), liquid (soil moisture) and gaseous components.

Biochemical processes in the soil determine its ability to self-purify, i.e. the ability to convert complex organic substances into simple - inorganic. Soil self-cleaning occurs more efficiently under aerobic conditions. In this case, two stages are distinguished: 1. Decay of organic substances (mineralization). 2. Synthesis of humus (humification).

The role of the soil:

the basis of all terrestrial and freshwater ecosystems (both natural and man-made).

Soil - the basis of plant nutrition provides biological productivity, i.e. it is the basis for the production of food for humans and other bionts.

The soil accumulates organic matter and various chemical elements and energy.

Cycles are not possible without soil - it regulates all the flows of matter in the biosphere.

The soil regulates the composition of the atmosphere and hydrosphere.

Soil is a biological absorber, destroyer and neutralizer of various contaminants. Soil contains half of all known microorganisms. When the soil is destroyed, the functioning that has developed in the biosphere is irreversibly disrupted, i.e., the role of the soil is colossal. Since the soil has become an object of industrial activity, this has generated a significant change in the state of land resources. These changes are not always positive.

Let us examine in more detail the components of the biosphere.

Earth's crust - it is a solid shell transformed in the course of geological time, which makes up the upper part of the Earth's lithosphere. A number of minerals in the earth's crust (limestone, chalk, phosphorites, oil, coal, etc.) arose from the tissues of dead organisms. It is a paradoxical fact that relatively small living organisms could cause phenomena of a geological scale, which is explained by their highest ability to reproduce. For example, under favorable conditions, the cholera virion can create a mass of matter equal to the mass of the earth's crust in just 1.75 days! It can be assumed that in the biospheres of previous eras, colossal masses of living matter moved around the planet, forming reserves of oil, coal, etc. as a result of death.

The biosphere exists by repeatedly using the same atoms. At the same time, the share of 10 elements located in the first half of the periodic system (oxygen - 29.5%, sodium, magnesium - 12.7%, aluminum, silicon - 15.2%, sulfur, potassium, calcium, iron - 34.6 %) accounts for 99% of the entire mass of our planet (the mass of the Earth is 5976 * 10 21 kg), and 1% is accounted for by the rest of the elements. However, the significance of these elements is very great - they play an essential role in living matter.

IN AND. Vernadsky divided all the elements of the biosphere into 6 groups, each of which performs certain functions in the life of the biosphere. First group – inert gases (helium, krypton, neon, argon, xenon). Second group – noble metals (ruthenium, palladium, platinum, osmium, iridium, gold). In the earth's crust, the elements of these groups are chemically inactive, their mass is insignificant (4.4 * 10 -4% of the mass of the earth's crust), and participation in the formation of living matter is poorly studied. The third group - lanthanides (14 chemical elements - metals) make up 0.02% of the mass of the earth's crust and their role in the biosphere has not been studied. Fourth group – radioactive elements are the main source of formation of the internal heat of the Earth and affect the growth of living organisms (0.0015% of the mass of the earth's crust). Some elements fifth group - scattered elements (0.027% of the earth's crust) - play an essential role in the life of organisms (for example, iodine and bromine). the biggest sixth group constitute cyclic elements , which, having undergone a series of transformations in geochemical processes, return to their original chemical states. This group includes 13 light elements (hydrogen, carbon, nitrogen, oxygen, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, potassium, calcium) and one heavy element (iron).

biota It is the totality of all types of plants, animals and microorganisms. Biota is an active part of the biosphere, which determines all the most important chemical reactions, as a result of which the main gases of the biosphere (oxygen, nitrogen, carbon monoxide, methane) are created and quantitative relationships are established between them. Biota continuously forms biogenic minerals and maintains a constant chemical composition of ocean waters. Its mass is no more than 0.01% of the mass of the entire biosphere and is limited by the amount of carbon in the biosphere. The main biomass is made up of green land plants - about 97%, and the biomass of animals and microorganisms - 3%.

The biota is mainly composed of cyclic elements. Particularly important is the role of such elements as carbon, nitrogen and hydrogen, the percentage of which in biota is higher than in the earth's crust (60 times carbon, 10 times nitrogen and hydrogen). The figure shows a diagram of a closed carbon cycle. Only thanks to the circulation of the main elements in such cycles (primarily carbon), the existence of life on Earth is possible.

Pollution of the lithosphere. Life, the biosphere and the most important link in its mechanism - the soil cover, commonly called the earth - make up the uniqueness of our planet in the universe. And in the evolution of the biosphere, in the phenomena of life on Earth, the importance of the soil cover (land, shallow waters and shelf) as a special planetary shell has invariably increased.

The soil cover is the most important natural formation. Its role in the life of society is determined by the fact that the soil is the main source of food, providing 95-97% of food resources for the world's population. A special property of the soil cover is its fertility , which is understood as a set of soil properties that ensure the yield of agricultural crops. The natural fertility of the soil is associated with the supply of nutrients in it and its water, air and thermal regimes. The soil provides the need for plants in water and nitrogen nutrition, being the most important agent of their photosynthetic activity. Soil fertility also depends on the amount of solar energy accumulated in it. The soil cover belongs to a self-regulating biological system, which is the most important part of the biosphere as a whole. Living organisms, plants and animals inhabiting the Earth fix solar energy in the form of phyto- or zoomass. The productivity of terrestrial ecosystems depends on the heat and water balances of the earth's surface, which determines the variety of forms of energy and matter exchange within the geographic envelope of the planet.

Particular attention should be paid to land resources. The area of ​​land resources in the world is 149 million km2, or 86.5% of the land area. Arable land and perennial plantations as part of agricultural land currently occupy about 15 million km 2 (10% of land), hayfields and pastures - 37.4 million km 2 (25%). The total area of ​​arable land is estimated by various researchers in different ways: from 25 to 32 million km 2. The planet's land resources make it possible to provide more people with food than is currently available and will be in the near future. However, due to population growth, especially in developing countries, the amount of arable land per capita is declining. Even 10-15 years ago, the mental security of the Earth's population with arable land was 0.45-0.5 hectares, at present it is already 0.35-37 hectares.

All usable material components of the lithosphere used in the economy as raw materials or energy sources are called mineral resources . Minerals can be ore if metals are extracted from it, and nonmetallic , if non-metallic components (phosphorus, etc.) are extracted from it or used as building materials.

If the mineral wealth is used as a fuel (coal, oil, gas, oil shale, peat, wood, nuclear energy) and at the same time as an energy source in engines to produce steam and electricity, then they are called fuel and energy resources .

Hydrosphere . Water occupies the predominant part of the Earth's biosphere (71% of the earth's surface) and makes up about 4% of the mass of the earth's crust. Its average thickness is 3.8 km, average depth - 3554 m, area: 1350 million km 2 - oceans, 35 million km 2 - fresh water.

The mass of ocean water accounts for 97% of the mass of the entire hydrosphere (2 * 10 21 kg). The role of the ocean in the life of the biosphere is enormous: the main chemical reactions occur in it, which determine the production of biomass and the chemical purification of the biosphere. So, in 40 days, the surface five-hundred-meter layer of water in the ocean passes through the plankton filtration apparatus, therefore (taking into account mixing) all the oceanic water of the ocean undergoes purification during the year. All components of the hydrosphere (atmospheric water vapor, waters of the seas, rivers, lakes, glaciers, swamps, groundwater) are in constant motion and renewal.

Water is the basis of the biota (living matter is 70% water) and its importance in the life of the biosphere is decisive. The most important functions of water can be named as:

1. biomass production;

2. chemical purification of the biosphere;

3. ensuring carbon balance;

4. climate stabilization (water plays the role of a buffer in thermal processes on the planet).

The great importance of the world ocean lies in the fact that it produces almost half of the total oxygen in the atmosphere with its phytoplankton, i.e. is a kind of "lung" of the planet. At the same time, the plants and microorganisms of the ocean in the process of photosynthesis absorb annually a much larger part of carbon dioxide than plants on land absorb.

living organisms in the ocean – hydrobionates - are divided into three main ecological groups: plankton, nekton and benthos. Plankton - a set of passively floating and carried by sea currents of plants (phytoplankton), living organisms (zooplankton) and bacteria (bacterioplankton). Nekton - this is a group of actively swimming living organisms moving over considerable distances (fish, cetaceans, seals, sea snakes and turtles, octopus squids, etc.). Benthos - these are organisms that live on the seabed: sessile (corals, algae, sponges); burrowing (worms, mollusks); crawling (crustaceans, echinoderms); floating freely at the bottom. The coastal areas of the oceans and seas are the richest in benthos.

The oceans are a source of huge mineral resources. Already, oil, gas, 90% bromine, 60% magnesium, 30% salt, etc. are being extracted from it. The ocean has huge reserves of gold, platinum, phosphorites, oxides of iron and manganese, and other minerals. The level of mining in the ocean is constantly growing.

Pollution of the hydrosphere. In many regions of the world, the state of water bodies is of great concern. Pollution of water resources, not without reason, is now regarded as the most serious threat to the environment. The river network actually functions as the natural sewer system of modern civilization.

The most polluted are inland seas. They have a longer coastline and are therefore more prone to pollution. The accumulated experience of the struggle for the purity of the seas shows that this is an incomparably more difficult task than the protection of rivers and lakes.

The processes of water pollution are caused by various factors. The main ones are: 1) discharge of untreated wastewater into water bodies; 2) flushing of pesticides with heavy rainfall; 3) gas and smoke emissions; 4) leakage of oil and oil products.

The greatest harm to water bodies is caused by the release of untreated wastewater into them - industrial, domestic, collector and drainage, etc. Industrial wastewater pollutes ecosystems with various components, depending on the specifics of industries.

The level of pollution of the Russian seas (with the exception of the White Sea), according to the State report "On the state of the environment of the Russian Federation", in 1998. exceeded the MPC for the content of hydrocarbons, heavy metals, mercury; surfactants (surfactants) on average 3-5 times.

The ingress of pollution to the ocean floor has a serious impact on the nature of biochemical processes. In this regard, the assessment of environmental safety in the planned extraction of minerals from the ocean floor, primarily iron-manganese nodules containing manganese, copper, cobalt and other valuable metals, is of particular importance. In the process of raking the bottom, the very possibility of life on the ocean floor will be destroyed for a long period, and the ingress of substances extracted from the bottom to the surface can adversely affect the air atmosphere of the region.

The huge volume of the World Ocean testifies to the inexhaustibility of the planet's natural resources. In addition, the World Ocean is a collector of land river waters, annually receiving about 39 thousand km 3 of water. The emerging pollution of the World Ocean threatens to disrupt the natural process of moisture circulation in its most critical link - evaporation from the surface of the ocean.

In the Water Code of the Russian Federation, the concept " water resources ” is defined as “reserves of surface and ground waters located in water bodies that are used or can be used” . Water is the most important component of the environment, a renewable, limited and vulnerable natural resource, used and protected in the Russian Federation as the basis of life and activity of the peoples living on its territory, ensures the economic, social, environmental well-being of the population, the existence of flora and fauna.

Any body of water or water source is associated with its external environment. It is influenced by the conditions for the formation of surface or underground water runoff, various natural phenomena, industry, industrial and municipal construction, transport, economic and domestic human activities. The consequence of these influences is the introduction of new, unusual substances into the aquatic environment - pollutants that degrade water quality. Pollution entering the aquatic environment is classified in different ways, depending on the approaches, criteria and tasks. So, usually allocate chemical, physical and biological pollution. Chemical pollution is a change in the natural chemical properties of water due to an increase in the content of harmful impurities in it, both inorganic (mineral salts, acids, alkalis, clay particles) and organic nature (oil and oil products, organic residues, surfactants, pesticides).

Despite the huge funds spent on the construction of treatment facilities, many rivers are still dirty, especially in urban areas. Pollution processes have even touched the oceans. And this does not seem surprising, since all caught in the rivers pollutants eventually rush to the ocean and reach it if they are difficult to decompose.

The environmental consequences of pollution of marine ecosystems are expressed in the following processes and phenomena:

violation of the stability of ecosystems;

progressive eutrophication;

the appearance of "red tides";

accumulation of chemical toxicants in biota;

decrease in biological productivity;

the occurrence of mutagenesis and carcinogenesis in the marine environment;

microbiological pollution of the coastal regions of the world.

Protecting the aquatic ecosystem is a complex and very important issue. To this end, the following environmental protection measures:

– development of waste-free and water-free technologies; introduction of water recycling systems;

– wastewater treatment (industrial, municipal, etc.);

– injection of sewage into deep aquifers;

– purification and disinfection of surface water used for water supply and other purposes.

The main pollutant of surface waters is wastewater, therefore, the development and implementation of effective wastewater treatment methods is a very urgent and environmentally important task. The most effective way to protect surface waters from pollution by sewage is the development and implementation of an anhydrous and waste-free production technology, the initial stage of which is the creation of a circulating water supply.

When organizing a recycling water supply system, it includes a number of treatment facilities and installations, which makes it possible to create a closed cycle for the use of industrial and domestic wastewater. With this method of water treatment, wastewater is always in circulation and their entry into surface water bodies is completely excluded.

Due to the huge variety of wastewater composition, there are various methods for their treatment: mechanical, physico-chemical, chemical, biological, etc. Depending on the degree of harmfulness and the nature of the pollution, wastewater treatment can be carried out by any one method or a set of methods (combined method). The treatment process involves the treatment of sludge (or excess biomass) and the disinfection of wastewater before being discharged into a reservoir.

In recent years, new effective methods have been actively developed that contribute to the environmental friendliness of wastewater treatment processes:

– electrochemical methods based on the processes of anodic oxidation and cathodic reduction, electrocoagulation and electroflotation;

– membrane purification processes (ultrafilters, electrodialysis, and others);

– magnetic treatment, which improves the flotation of suspended particles;

– radiation purification of water, which makes it possible to subject pollutants to oxidation, coagulation and decomposition in the shortest possible time;

- ozonation, in which wastewater does not form substances that adversely affect natural biochemical processes;

- introduction of new selective types for the selective separation of useful components from wastewater for the purpose of recycling, and others.

It is known that pesticides and fertilizers washed off by surface runoff from agricultural land play a role in the contamination of water bodies. To prevent the ingress of polluting effluents into water bodies, a set of measures is required, including:

compliance with the norms and terms of applying fertilizers and pesticides;

focal and tape treatment with pesticides instead of continuous;

application of fertilizers in the form of granules and, if possible, together with irrigation water;

replacement of pesticides by biological methods of plant protection.

Measures for the protection of waters and seas and the World Ocean are to eliminate the causes of deterioration in the quality and pollution of waters. Special measures to prevent pollution of sea water should be envisaged in the exploration and development of oil and gas fields on the continental shelves. It is necessary to introduce a ban on the dumping of toxic substances in the ocean and maintain a moratorium on nuclear weapons testing.

Atmosphere - the air environment around the Earth, its mass is about 5.15 * 10 18 kg. It has a layered structure and consists of several spheres, between which there are transitional layers - pauses. In the spheres, the amount of air and temperature change.

Depending on the distribution of temperature, the atmosphere is divided into:

– troposphere (its length in height in the middle latitudes is 10-12 km above sea level, at the poles - 7-10, above the equator - 16-18 km, more than 4/5 of the mass of the earth's atmosphere is concentrated here; due to the uneven heating of the earth's surface in powerful vertical air currents are formed in the troposphere, instability of temperature, relative humidity, pressure is noted, the air temperature in the troposphere decreases in height by 0.6 ° C for every 100 m and ranges from +40 to -50 ° C);

– stratosphere (has a length of about 40 km, the air in it is rarefied, the humidity is low, the air temperature is from -50 to 0 ° C at altitudes of about 50 km; in the stratosphere, under the influence of cosmic radiation and the short-wave part of the ultraviolet radiation of the sun, air molecules are ionized, resulting in the formation ozone layer located at an altitude of 25-40 km);

– mesosphere (from 0 to -90 o C at altitudes of 50-55 km);

– thermosphere (it is characterized by a continuous increase in temperature with increasing altitude - at an altitude of 200 km 500 ° C, and at an altitude of 500-600 km it exceeds 1500 ° C; in the thermosphere, gases are very rarefied, their molecules move at high speed, but rarely collide with each other and therefore cannot cause even a slight heating of the body located here);

– exosphere (from several hundred km).

Uneven heating contributes to the general circulation of the atmosphere, which affects the weather and climate of the Earth.

The gas composition of the atmosphere is as follows: nitrogen (79.09%), oxygen (20.95%), argon (0.93%), carbon dioxide (0.03%) and a small amount of inert gases (helium, neon, krypton, xenon ), ammonia, methane, hydrogen, etc. . The lower layers of the atmosphere (20 km) contain water vapor, the amount of which decreases rapidly with height. At an altitude of 110-120 km, almost all oxygen becomes atomic. It is assumed that above 400-500 km and nitrogen is in the atomic state. The oxygen-nitrogen composition persists approximately up to an altitude of 400-600 km. The ozone layer, which protects living organisms from harmful short-wave radiation, is located at an altitude of 20-25 km. Above 100 km, the proportion of light gases increases, and at very high altitudes, helium and hydrogen predominate; part of the gas molecules break down into atoms and ions, forming ionosphere . Air pressure and density decrease with height.

Air pollution. The atmosphere has a huge impact on biological processes on land and in water bodies. The oxygen contained in it is used in the process of respiration of organisms and during the mineralization of organic matter, carbon dioxide is consumed during photosynthesis by autotrophic plants, and ozone reduces the ultraviolet radiation of the sun harmful to organisms. In addition, the atmosphere contributes to the preservation of the Earth's heat, regulates the climate, perceives gaseous metabolic products, transports water vapor around the planet, etc. Without an atmosphere, the existence of any complex organisms is impossible. Therefore, the issues of preventing air pollution have always been and remain relevant.

To assess the composition and pollution of the atmosphere, the concept of concentration (C, mg/m 3) is used.

Pure natural air has the following composition (in % vol): nitrogen 78.8%; oxygen 20.95%; argon 0.93%; CO 2 0.03%; other gases 0.01%. It is believed that such a composition should correspond to air at a height of 1 m above the ocean surface away from the coast.

As for all other components of the biosphere, there are two main sources of pollution for the atmosphere: natural and anthropogenic (artificial). The entire classification of pollution sources can be represented according to the above structural diagram: industry, transport, energy are the main sources of air pollution. According to the nature of the impact on the biosphere, atmospheric pollutants can be divided into 3 groups: 1) affecting global climate warming; 2) destroying biota; 3) destroying the ozone layer.

Let us note the brief characteristics of some atmospheric pollutants.

To pollutants first group should include CO 2, nitrous oxide, methane, freons. Into the creation greenhouse effect » The main contributor is carbon dioxide, whose concentration increases by 0.4% annually (for more on the greenhouse effect, see chapter 3.3). Compared with the middle of the XIX century, the content of CO 2 increased by 25%, nitrous oxide by 19%.

Freons - chemical compounds that are not characteristic of the atmosphere, used as refrigerants - are responsible for 25% of the creation of the greenhouse effect in the 90s. Calculations show that, despite the Montreal Agreement of 1987. on limiting the use of freons, by 2040. the concentration of the main freons will increase significantly (chlorofluorocarbon from 11 to 77%, chlorofluorocarbon - from 12 to 66%), which will lead to an increase in the greenhouse effect by 20%. The increase in the content of methane in the atmosphere was insignificant, but the specific contribution of this gas is about 25 times higher than that of carbon dioxide. If you do not stop the flow of "greenhouse" gases into the atmosphere, the average annual temperatures on Earth by the end of the 21st century will rise by an average of 2.5-5 ° C. It is necessary: ​​to reduce the burning of hydrocarbon fuels and deforestation. The latter is dangerous, in addition to leading to an increase in carbon in the atmosphere, it will also cause a decrease in the assimilating capacity of the biosphere.

To pollutants second group should include sulfur dioxide, suspended solids, ozone, carbon monoxide, nitric oxide, hydrocarbons. Of these substances in the gaseous state, sulfur dioxide and nitrogen oxides cause the greatest damage to the biosphere, which, in the course of chemical reactions, are converted into small crystals of sulfuric and nitric acid salts. The most acute problem is air pollution with sulfur-containing substances. Sulfur dioxide is harmful to plants. Entering the leaf during respiration, SO 2 inhibits the vital activity of cells. In this case, the leaves of the plants are first covered with brown spots, and then dry up.

Sulfur dioxide and its other compounds irritate the mucous membranes of the eyes and the respiratory tract. Prolonged action of low concentrations of SO 2 leads to chronic gastritis, hepatopathy, bronchitis, laryngitis and other diseases. There is evidence of a relationship between the content of SO 2 in the air and the death rate from lung cancer.

In the atmosphere, SO 2 is oxidized to SO 3. Oxidation occurs catalytically under the influence of trace metals, mainly manganese. In addition, SO 2 gaseous and dissolved in water can be oxidized with ozone or hydrogen peroxide. Combining with water, SO 3 forms sulfuric acid, which forms sulfates with the metals present in the atmosphere. The biological effect of acid sulfates at equal concentrations is more pronounced compared to SO 2 . Sulfur dioxide exists in the atmosphere from several hours to several days, depending on humidity and other conditions.

In general, aerosols of salts and acids penetrate into sensitive tissues of the lungs, devastate forests and lakes, reduce crops, destroy buildings, architectural and archaeological monuments. Suspended particulate matter poses a public health hazard that outweighs that of acid aerosols. Basically, this is the danger of big cities. Particularly harmful solids are found in the exhaust gases of diesel engines and two-stroke gasoline engines. Most particulate matter in the air of industrial origin in developed countries is successfully captured by all sorts of technical means.

Ozone in the surface layer appears as a result of the interaction of hydrocarbons formed during the incomplete combustion of fuel in automobile engines and released during many production processes, with nitrogen oxides. It is one of the most dangerous pollutants affecting the respiratory system. It is most intense in hot weather.

Carbon monoxide, nitrogen oxides and hydrocarbons mainly enter the atmosphere with vehicle exhaust gases. All of these chemical compounds have a devastating effect on ecosystems at concentrations even lower than those permissible for humans, namely: they acidify water basins, killing living organisms in them, destroy forests, and reduce crop yields (ozone is especially dangerous). Studies in the United States have shown that current concentrations of ozone reduce the yield of sorghum and corn by 1%, cotton and soybeans by 7%, and alfalfa by more than 30%.

Of the pollutants that destroy the stratospheric ozone layer, freons, nitrogen compounds, exhausts of supersonic aircraft and rockets should be noted.

Fluorochlorohydrocarbons, which are widely used as refrigerants, are considered the main source of chlorine in the atmosphere. They are used not only in refrigeration units, but also in numerous household aerosol cans with paints, varnishes, insecticides. Freon molecules are resistant and can be transported almost unchanged with atmospheric masses over great distances. At altitudes of 15–25 km (the zone of maximum ozone content), they are exposed to ultraviolet rays and decompose with the formation of atomic chlorine.

It has been established that over the past decade, the loss of the ozone layer amounted to 12–15% in the polar and 4–8% in the middle latitudes. In 1992, stunning results were established: areas with a loss of the ozone layer up to 45% were found at the latitude of Moscow. Already now, due to increased ultraviolet insolation, there is a decrease in yields in Australia and New Zealand, an increase in skin cancer.

Technogenic substances of the biosphere that have a harmful effect on biota are classified as follows (a general classification is given that is valid not only for gaseous substances). According to the degree of danger, all harmful substances are divided into four classes (Table 2):

I - extremely dangerous substances;

II - highly hazardous substances;

III - moderately hazardous substances;

IV - low-hazard substances.

The assignment of a harmful substance to a hazard class is carried out according to the indicator, the value of which corresponds to the highest hazard class.

Here: A) is a concentration that, during daily (except weekends) work for 8 hours, or another duration, but not more than 41 hours a week, during the entire working experience cannot cause diseases or deviations in the state of health detected by modern research methods in the process of work or in the remote periods of life of the present and subsequent generations;

B) - the dose of a substance that causes the death of 50% of animals with a single injection into the stomach;

C) - dose of a substance that causes the death of 50% of animals with a single application to the skin;

D) - the concentration of a substance in the air, causing the death of 50% of animals with a 2-4 hour inhalation exposure;

E) - the ratio of the maximum allowable concentration of a harmful substance in the air at 20 ° C to the average lethal concentration for mice;

E) - the ratio of the average lethal concentration of a harmful substance to the minimum (threshold) concentration that causes a change in biological indicators at the level of the whole organism, beyond the limits of adaptive physiological reactions;

G) - The ratio of the minimum (threshold) concentration that causes a change in biological parameters at the level of the whole organism, beyond the limits of adaptive physiological reactions, to the minimum (threshold) concentration that causes a harmful effect in a chronic experiment for 4 hours, 5 times a week for at least 4 -x months.

Table 2 Classification of harmful substances

Indicator	Norm for hazard class
(A) Maximum permissible concentration (MPC) of harmful substances in the air of the working area, mg / m 3
(B) Mean lethal dose when injected into the stomach (MAD), mg/kg				over 5000
(B) Mean lethal dose when applied to the skin (MTD), mg/kg				over 2500
(D) Mean lethal concentration in air (TLC), mg/m 3				more than 50000
(E) Inhalation Poisoning Possibility Ratio (POI)
(E) Acute action zone (ZAZ)
(G) Chronic zone (ZZhA)	over 10.0

The danger of atmospheric pollutants for human health depends not only on their content in the air, but also on the hazard class. For a comparative assessment of the atmosphere of cities, regions, taking into account the hazard class of pollutants, the air pollution index is used.

Single and complex indices of air pollution can be calculated for different time intervals - for a month, a year. At the same time, the average monthly and average annual concentrations of pollutants are used in the calculations.

For those pollutants for which MPCs have not been established ( maximum allowable concentration ), is set estimated safe exposure levels (SHEETS). As a rule, this is explained by the fact that there is no experience gained in their use, sufficient to judge the long-term consequences of their impact on the population. If in technological processes substances are released and enter the air environment for which there are no approved MPCs or SHELs, enterprises are required to apply to the territorial bodies of the Ministry of Natural Resources to establish temporary standards. In addition, for some substances that pollute the air from time to time, only one-time MPCs have been established (for example, for formalin).

For some heavy metals, not only the average daily content in the atmospheric air (MPC ss) is normalized, but also the maximum allowable concentration during single measurements (MPC rz) in the air of the working area (for example, for lead - MPC ss = 0.0003 mg / m 3, and MPC pz \u003d 0.01 mg / m 3).

Permissible concentrations of dusts and pesticides in the atmospheric air are also standardized. So, for dust containing silicon dioxide, MPC depends on the content of free SiO 2 in it; when the content of SiO 2 changes from 70% to 10%, MPC changes from 1 mg/m 3 to 4.0 mg/m 3 .

Some substances have a unidirectional harmful effect, which is called the summation effect (for example, acetone, acrolein, phthalic anhydride - group 1).

Anthropogenic atmospheric pollution can be characterized by the duration of their presence in the atmosphere, by the rate of increase in their content, by the scale of influence, by the nature of the influence.

The duration of the presence of the same substances is different in the troposphere and stratosphere. So, CO 2 is present in the troposphere for 4 years, and in the stratosphere - 2 years, ozone - 30-40 days in the troposphere, and 2 years in the stratosphere, and nitric oxide - 150 years (both there and there).

The rate of accumulation of pollution in the atmosphere is different (probably related to the utilization capacity of the biosphere). So the content of CO 2 increases by 0.4% per year, and nitrogen oxides - by 0.2% per year.

Basic principles of hygienic regulation of atmospheric pollutants.

The hygienic standardization of atmospheric pollution is based on the following criteria for the harmfulness of atmospheric pollution :

1. Only such a concentration of a substance in the atmospheric air can be recognized as permissible, which does not have a direct or indirect harmful and unpleasant effect on a person, does not reduce his working capacity, does not affect his well-being and mood.

2. Addiction to harmful substances should be considered as an unfavorable moment and proof of the inadmissibility of the studied concentration.

3. Such concentrations of harmful substances that adversely affect the vegetation, the climate of the area, the transparency of the atmosphere and the living conditions of the population are unacceptable.

The solution of the issue of the permissible content of atmospheric pollution is based on the idea of ​​the presence of thresholds in the action of pollution.

When scientifically substantiating the MPC of harmful substances in the atmospheric air, the principle of a limiting indicator is used (rationing according to the most sensitive indicator). So, if the smell is felt at concentrations that do not have a harmful effect on the human body and the environment, the rationing is carried out taking into account the threshold of smell. If a substance has a harmful effect on the environment in lower concentrations, then in the course of hygienic regulation, the threshold of action of this substance on the environment is taken into account.

For substances polluting the atmospheric air, two standards have been established in Russia: one-time and average daily MPC.

The maximum one-time MPC is set to prevent reflex reactions in humans (sense of smell, changes in the bioelectrical activity of the brain, light sensitivity of the eyes, etc.) with short-term (up to 20 minutes) exposure to atmospheric pollution, and the average daily one is set to prevent their resorptive (general toxic, mutagenic, carcinogenic, etc.) influences.

Thus, all components of the biosphere experience a colossal technogenic influence of man. At present, there is every reason to speak of the technosphere as a "sphere of unreason".

Questions for self-control

1. Group classification of elements of the biosphere V.I. Vernadsky.

2. What factors determine soil fertility?

3. What is the "hydrosphere"? Distribution and role of water in nature.

4. In what forms are harmful impurities present in wastewater, and how does this affect the choice of wastewater treatment methods?

5. Distinctive features of different layers of the atmosphere.

6. The concept of a harmful substance. Hazard classes of harmful substances.

7. What is MPC? Units of measurement of MPC in air and in water. Where are MPCs of harmful substances controlled?

8. How are the sources of emission and emissions of harmful substances into the atmosphere divided?

3.3 Circulation of substances in the biosphere . Biospheric carbon cycle. Greenhouse effect: the mechanism of occurrence and possible consequences.

The processes of photosynthesis of organic substances continue for hundreds of millions of years. But since the Earth is a finite physical body, any chemical elements are also physically finite. Over millions of years, they should, it would seem, be exhausted. However, this does not happen. Moreover, man constantly intensifies this process, increasing the productivity of the ecosystems he has created.

All substances on our planet are in the process of biochemical circulation of substances. There are 2 main circuits big or geological and small or chemical.

big circuit lasts for millions of years. It lies in the fact that rocks are destroyed, the products of destruction are carried away by water flows into the oceans or partially return to land along with precipitation. The processes of subsidence of the continents and the uplift of the seabed for a long time lead to the return of these substances to land. And the process starts again.

Small circuit , being part of a larger one, occurs at the ecosystem level and lies in the fact that soil nutrients, water, carbon are accumulated in plant matter and are spent on building the body and life processes. The decomposition products of the soil microflora again decompose to mineral components available to plants and are again involved in the flow of matter.

The circulation of chemicals from the inorganic environment through plants and animals back to the inorganic environment using solar energy of chemical reactions is called biochemical cycle .

The complex mechanism of evolution on Earth is determined by the chemical element "carbon". Carbon - an integral part of rocks and in the form of carbon dioxide is contained in part of the atmospheric air. Sources of CO2 are volcanoes, respiration, forest fires, fuel combustion, industry, etc.

The atmosphere intensively exchanges carbon dioxide with the world's oceans, where it is 60 times more than in the atmosphere, because. CO 2 is highly soluble in water (the lower the temperature, the higher the solubility, i.e. it is more in low latitudes). The ocean acts like a giant pump: it absorbs CO 2 in cold areas and partially "blows it out" in the tropics.

Excess carbon monoxide in the ocean combines with water to form carbonic acid. Combining with calcium, potassium, sodium, it forms stable compounds in the form of carbonates, which settle to the bottom.

Phytoplankton in the ocean absorb carbon dioxide during photosynthesis. Dead organisms fall to the bottom and become part of the sedimentary rocks. This shows the interaction of large and small circulation of substances.

Carbon from the CO 2 molecule during photosynthesis is included in the composition of glucose, and then in the composition of more complex compounds from which plants are built. Subsequently, they are transferred along food chains and form the tissues of all other living organisms in the ecosystem and are returned to the environment as part of CO 2 .

Carbon is also present in oil and coal. By burning fuel, a person also completes the cycle of carbon contained in the fuel - this is how biotechnical carbon cycle.

The remaining mass of carbon is found in carbonate deposits of the ocean floor (1.3-10t), in crystalline rocks (1-10t), in coal and oil (3.4-10t). This carbon takes part in the ecological cycle. Life on Earth and the gas balance of the atmosphere is maintained by a relatively small amount of carbon (5-10 tons).

There is a widespread opinion that global warming and its consequences threaten us due to industrial heat generation. That is, all the energy consumed in everyday life, industry and transport heats the Earth and the atmosphere. However, the simplest calculations show that the heating of the Earth by the Sun is many orders of magnitude higher than the results of human activity.

Scientists also consider the increase in the concentration of carbon dioxide in the Earth's atmosphere to be the probable cause of global warming. It is he who causes the so-called « greenhouse effect ».

What is the greenhouse effect ? We encounter this phenomenon very often. It is well known that at the same daytime temperature, the nighttime temperature is different, depending on the cloudiness. Cloudiness covers the earth like a blanket, and a cloudy night is 5-10 degrees warmer than a cloudless one at the same daytime temperature. However, if clouds, which are the smallest droplets of water, do not allow heat to pass both outside and from the Sun to the Earth, then carbon dioxide works like a diode - heat from the Sun comes to the Earth, but not back.

Humanity is consuming a huge amount of natural resources, burning more and more fossil fuels, as a result of which the percentage of carbon dioxide in the atmosphere increases, and it does not release infrared radiation from the heated surface of the Earth into space, creating a “greenhouse effect”. The consequence of a further increase in the concentration of carbon dioxide in the atmosphere may be global warming and an increase in the temperature of the Earth, which, in turn, will lead to such consequences as the melting of glaciers and the rise in the level of the world ocean by tens or even hundreds of meters, many coastal cities of the world.

This is a possible scenario for the development of events and the consequences of global warming, the cause of which is the greenhouse effect. However, even if all the glaciers of Antarctica and Greenland melt, the level of the world ocean will rise by a maximum of 60 meters. But this is an extreme, hypothetical case, which can only occur with the sudden melting of the glaciers of Antarctica. And for this, a positive temperature must be established in Antarctica, which can only be a consequence of a catastrophe on a planetary scale (for example, a change in the inclination of the earth's axis).

Among the supporters of the "greenhouse catastrophe" there is no unanimity about its likely scale, and the most authoritative of them do not promise anything terrible. The marginal warming, in the case of doubling the concentration of carbon dioxide, can be a maximum of 4°C. In addition, it is likely that with global warming and rising temperatures, the level of the ocean will not change, or even, on the contrary, will decrease. After all, with an increase in temperature, precipitation will also intensify, and the melting of the margins of glaciers can be compensated by increased snowfall in their central parts.

Thus, the problem of the greenhouse effect and the global warming it causes, as well as their possible consequences, although it exists objectively, the scale of these phenomena is clearly exaggerated today. In any case, they require very thorough research and long-term observation.

An international congress of climatologists, held in October 1985, was devoted to the analysis of the possible climatic consequences of the greenhouse effect. in Villach (Austria). The congress participants came to the conclusion that even a slight warming of the climate will lead to a noticeable increase in evaporation from the surface of the World Ocean, resulting in an increase in the amount of summer and winter precipitation over the continents. This increase will not be uniform. It is calculated that a strip will stretch across the south of Europe from Spain to Ukraine, within which the amount of precipitation will remain the same as now, or even slightly decrease. To the north of 50 ° (this is the latitude of Kharkov) both in Europe and in America it will gradually increase with fluctuations, which we have been observing over the past decade. Consequently, the flow of the Volga will increase, and the Caspian Sea is not threatened by a decrease in the level. This was the main scientific argument, which finally made it possible to abandon the project of transferring part of the flow of northern rivers to the Volga.

The most accurate, convincing data on the possible consequences of the greenhouse effect are provided by paleogeographic reconstructions compiled by specialists studying the geological history of the Earth over the past million years. After all, during this “recent” time of geological history, the climate of the Earth was subjected to very sharp global changes. In epochs colder than today, continental ice, like those that now hold down Antarctica and Greenland, covered all of Canada and the whole of northern Europe, including the places where Moscow and Kyiv now stand. Herds of reindeer and shaggy mammoths roamed the tundra of the Crimea and the North Caucasus, where the remains of their skeletons are now found. And in the intermediate interglacial epochs, the climate of the Earth was much warmer than the current one: the continental ice in North America and Europe melted, in Siberia the permafrost thawed for many meters, the sea ice near our northern shores disappeared, forest vegetation, judging by the fossil spore-pollen spectra , extended to the territory of modern tundra. Powerful river streams flowed across the plains of Central Asia, filling the basin of the Aral Sea with water up to a mark of plus 72 meters, many of them carried water to the Caspian Sea. The Karakum desert in Turkmenistan is the scattered sand deposits of these ancient channels.

In general, the physical-geographical situation during the warm interglacial epochs throughout the entire territory of the former USSR was more favorable than now. It was the same in the Scandinavian countries and the countries of Central Europe.

Unfortunately, until now, geologists studying the geological history of the last million years of the evolution of our planet have not been involved in the discussion of the problem of the greenhouse effect. And geologists could make valuable additions to existing ideas. In particular, it is obvious that for a correct assessment of the possible consequences of the greenhouse effect, paleographic data on past epochs of significant global climate warming should be more widely used. An analysis of such data, known today, allows us to think that the greenhouse effect, contrary to popular belief, does not bring any disasters for the peoples of our planet. On the contrary, in many countries, including Russia, it will create more favorable climatic conditions than now.

Questions for self-control

1. The essence of the main biochemical circulations of substances.

2. What is the biochemical carbon cycle?

3. What is meant by the term "greenhouse effect" and what is it associated with? Your brief assessment of the problem.

4. Do you think there is a threat of global warming? Justify your answer