Water resources examples. Hydraulic systems and structures. Measures to improve water quality

Looking at our planet from the heights of outer space, a comparison immediately arises with a blue ball, which is completely covered with water. At this time, the continents seem to be small islands in this endless ocean. This is quite natural, because water occupies 79.8% of the entire surface, and 29.2% falls on land. The water shell of the Earth is called the hydrosphere; its volume is 1.4 billion m3.

Water resources and their purpose

Water resources- These are waters from rivers, lakes, canals, reservoirs, seas and oceans that are suitable for use in agriculture. This also includes groundwater, soil moisture, swamps, glaciers, and atmospheric water vapor.

Water appeared on the planet about 3.5 billion years ago and initially it was in the form of vapors that were released during the degassing of the mantle. Today, water is the most important element in the Earth's biosphere, because nothing can replace it. However, recently, water resources have ceased to be considered limited, because scientists have managed desalinate salt water.

Purpose of water resources- support the vital activity of all life on Earth (humans, plants and animals). Water is the basis of all living things and the main supplier of oxygen in the process of photosynthesis. Water also takes part in climate formation - absorbing heat from the atmosphere in order to release it in the future, thereby regulating climate processes.

It would be worth remembering that water sources play an honorable role in the modification of our planet. People have always settled near reservoirs or water sources. Thus, water promotes communication. There is a hypothesis among scientists that if there were no water on Earth, the discovery of America would have been postponed for several centuries. And Australia would still be unknown today.

Types of water resources

As already said water resources- these are all the water reserves on the planet. But on the other hand, water is the most common and most specific compound on Earth, because only it can exist in three states (liquid, gaseous and solid).

The Earth's water resources consist of:

• surface water(oceans, seas, lakes, rivers, swamps) are the most valuable source of fresh water, but the thing is that these objects are distributed quite unevenly over the Earth’s surface. So, in the equatorial belt, as well as in the northern part temperate zone water is in excess (25 thousand m 3 per year per person). And the tropical continents, which consist of 1/3 of the land, are very acutely aware of the shortage of water reserves. Based on this situation, their agriculture develops only under the condition of artificial irrigation;
• groundwater;
• reservoirs created artificially by man;
• glaciers and snowfields (frozen water from glaciers in Antarctica, the Arctic and snowy mountain peaks). This is where most of the fresh water is found. However, these reserves are practically unavailable for use. If all the glaciers are distributed over the Earth, then this ice will cover the earth with a ball 53 cm high, and by melting it, we thereby raise the level of the World Ocean by 64 meters;
• moisture what is found in plants and animals;
• vapor state of the atmosphere.

Water consumption

The total volume of the hydrosphere is amazing in its quantity, however, only 2% of this figure is fresh water, moreover, only 0.3% is available for use. Scientists have calculated the freshwater resources that are necessary for all humanity, animals and plants. It turns out that the supply of water resources on the planet is only 2.5% of the required volume of water.

Around the world, about 5 thousand m3 are consumed annually, while more than half of the consumed water is lost irrevocably. In percentage terms, the consumption of water resources will have the following characteristics:

• agriculture - 63%;

• industrial water consumption - 27% of the total;

• municipal needs take 6%;
• reservoirs consume 4%.

Few people know that in order to grow 1 ton of cotton, 10 thousand tons of water are required, 1 ton of wheat requires 1500 tons of water, the production of 1 ton of steel requires 250 tons of water, and 1 ton of paper requires at least 236 thousand tons of water.

A person should consume at least 2.5 liters of water per day, but on average this same person spends at least 360 liters per day in a large city, since this figure includes all possible uses of water, including watering streets, washing vehicles and even firefighting.

But the consumption of water resources does not end there. This is evidenced, for example, by water transport or the process of breeding both marine and fresh fish. Moreover, for breeding fish you need exclusively clean water, saturated with oxygen and free of harmful impurities.

A great example of the use of water resources is recreational areas. There is no such person who would not like to relax by a pond, relax, and swim. In the world, almost 90% of recreational areas are located near bodies of water.

The need to protect water resources

Considering the current situation, we can conclude that water requires a protective attitude towards itself. Currently, there are two ways to conserve water resources:

• reduce fresh water consumption;
• creation of modern high quality collectors.

Storing water in reservoirs limits its flow into the world's oceans. Storing water underground helps prevent its evaporation. The construction of canals can easily solve the issue of delivering water without penetrating into the ground. Humanity is also thinking about the latest methods of irrigating agricultural land, making it possible to moisten the territory using wastewater.

But each of the above methods actually affects the biosphere. The reservoir system, for example, does not allow the formation of fertile silt deposits; canals interfere with the replenishment of groundwater. Therefore, today one of the most effective ways to conserve water resources is wastewater treatment. Science does not stand still in this regard, and various methods make it possible to neutralize or remove up to 96% of harmful substances.

Water pollution problem

Population growth, the rise of production and agriculture... These factors contributed to the shortage of fresh water. In addition, the share of polluted water resources is also growing.

Main sources of pollution:

• industrial waste;
• municipal wastewater;
• plums from the fields (meaning when they are oversaturated with chemicals and fertilizers;
• burial of radioactive substances near a body of water;
• wastewater coming from livestock complexes (water is characterized by an excess of biogenic organic matter);
• shipping.

Nature provides for self-purification of water bodies. This happens due to the presence of plankton in the water, ultraviolet rays entering the water, and the sedimentation of insoluble particles. But unfortunately there is much more pollution and nature on its own is not able to cope with such a mass of harmful substances that man and his activities provide to water resources.

Unusual sources of drinking water

Recently, humanity has been thinking about how to use unconventional sources of water resources. Here are the main ones:

• tow icebergs from the Arctic or Antarctica;
• carry out desalination of sea waters (actively used at the moment);
• condense atmospheric water.

In order to obtain fresh water by desalinating salt water, desalination stations are installed on sea vessels. There are already about hundreds of such units in the whole world. The world's largest producer of such water is Kuwait.

Fresh water has recently acquired the status of a global commodity; it is transported in tankers using long-distance water pipelines. This scheme works successfully in the following areas:

• the Netherlands gets water from Norway;
• Saudi Arabia receives resource from Philippines;
• Singapore imports from Malaysia;
• water is pumped from Greenland and Antarctica to Europe;
• The Amazon transports drinking water to Africa.

One of the latest achievements is installations with the help of which the heat of nuclear reactors is used simultaneously for desalination of sea water and production of electricity. At the same time, the price of one liter of water costs little, since the productivity of such installations is quite high. It is recommended to use water that has passed through this route for irrigation.

Reservoirs can also help overcome freshwater shortages by regulating river flow. In total, more than 30 thousand reservoirs have been built in the world. In most countries, there are projects for the redistribution of river flow through its transfer. But most of these programs have been rejected due to environmental concerns.

Water resources of the Russian Federation

Our country has a unique water resource potential. However, their main drawback is their extremely uneven distribution. So, if we compare the Southern and Far Eastern federal districts of Russia, then in terms of the size of local water resources they differ from each other by 30 times, and in terms of water supply - by 100 times.

Rivers of Russia

When thinking about the water resources of Russia, first of all, we should note the rivers. Their volume is 4,270 km 3 . There are 4 water basins on the territory of Russia:

• the seas of the Northern and Arctic Oceans, as well as the large rivers flowing into them (Northern Dvina, Pechora, Ob, Yenisei, Lena, Kolyma);
• seas Pacific Ocean(Amur and Anadyr);
• seas of the Atlantic Ocean (Don, Kuban, Neva);
• the internal basin of the Caspian Sea and the flowing Volga and Ural.

Since in the central regions the population density is greater than, for example, in Siberia, this leads to the disappearance of small rivers and water pollution in general.

Lakes and swamps of Russia

Half of all fresh water in the country comes from lakes. Their number in the country is approximately 2 million. Of these, the largest ones are:

• Baikal;
• Ladoga;
• Onega;
• Taimyr;
• Khanka;
• Vats;
• Ilmen;
• White.

A special place should be given to Lake Baikal, because 90% of our fresh water reserves are concentrated in it. In addition to the fact that this lake is the deepest on earth, it is also characterized by a unique ecosystem. Baikal is also included in the UNESCO natural heritage list.

Lakes of the Russian Federation are used for irrigation and as sources for water supply. Some of the listed lakes have a decent supply of medicinal mud and therefore are used for recreational purposes. Just like rivers, lakes are characterized by their uneven distribution. They are mainly concentrated in the Northwestern part of the country ( Kola Peninsula and the Republic of Karelia), the Ural region, Siberia and Transbaikalia.

The swamps of Russia also play a lot important role, although many people disrespect them by draining them. Such actions lead to the death of entire huge ecosystems, and as a result, rivers do not have the opportunity to cleanse themselves naturally. Swamps also feed rivers and act as their controlled object during floods and floods. And of course, swamps are a source of peat reserves.

These elements of water resources are widespread in the North-West and North-Central part of Siberia; the total area of ​​swamps in Russia is 1.4 million km 2.

As we see, Russia has great water resource potential, but we should not forget about the balanced use of this resource and treat it with care, because anthropogenic factors and huge consumption lead to pollution and depletion of water resources.

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If you look at our planet from space, the Earth appears as a blue ball completely covered with water. And the continents are like small islands in this endless ocean. This is understandable. Water occupies 70.8% of the planet's surface, leaving only 29.2% of land. The watery shell of our planet is called the hydrosphere. Its volume is 1.4 billion cubic meters.

Water appeared on our planet about 3.5 billion years ago in the form of vapor that was formed as a result of degassing of the mantle. Currently, water is the most important element in the Earth's biosphere, since it cannot be replaced by anything. Fortunately, water resources are considered inexhaustible because scientists have come up with a way to desalinate salt water.

The main purpose of water as a natural resource is to support the life of all living things - plants, animals and humans. It is the basis of all life on our planet, the main supplier of oxygen in important process on Earth - photosynthesis.

Water is the most important factor in climate formation. By absorbing heat from the atmosphere and releasing it back, water regulates climate processes.

It is impossible not to note the role of water sources in the modification of our planet. From time immemorial, people have settled near reservoirs and water sources. Water serves as one of the main means of communication. There is an opinion among scientists that if our planet were entirely dry land, then, for example, the discovery of America would be delayed for several centuries. And we would hardly have learned about Australia for another 300 years.

Types of Earth's water resources

The water resources of our planet are the reserves of all water. But water is one of the most common and most unique compounds on Earth, since it is present in three states at once: liquid, solid and gaseous. Therefore, the Earth's water resources are:

. Surface waters (oceans, lakes, rivers, seas, swamps)

. The groundwater.

. Artificial reservoirs.

. Glaciers and snowfields (frozen water from glaciers in Antarctica, the Arctic and highlands).

. Water contained in plants and animals.

. Atmospheric vapors.

The last 3 points relate to potential resources, because humanity has not yet learned to use them.

Fresh water is the most valuable; it is used much more widely than sea, salt water. Of the total water reserves in the world, 97% of water comes from seas and oceans. 2% of fresh water is contained in glaciers, and only 1% is fresh water reserves in lakes and rivers.

Use of water resources

Water resources - essential component and human life. People use water in industry and at home.

According to statistics, most water resources are used in agriculture (about 66% of all fresh water reserves). About 25% is used by industry and only 9% goes to meet the needs of utilities and households.

For example, to grow 1 ton of cotton, about 10 thousand tons of water are needed, for 1 ton of wheat - 1,500 tons of water. To produce 1 ton of steel, 250 tons of water are required, and to produce 1 ton of paper, at least 236 thousand tons of water are needed.

A person needs to drink at least 2.5 liters of water per day. However, on average, 1 person in large cities spends at least 360 liters per day. This includes the use of water in sewers, water supply, for watering streets and extinguishing fires, for washing vehicles, etc., etc.

Another option for using water resources is water transport. Every year, over 50 million tons of cargo are transported across Russian waters alone.

Don't forget about fisheries. Marine and freshwater fish plays an important role in the economies of countries. Moreover, fish farming requires clean water, saturated with oxygen and free of harmful impurities.

An example of the use of water resources is also recreation. Who among us doesn’t like to relax by the sea, barbecue on the river bank or swim in the lake? In the world, 90% of recreational facilities are located near water bodies.

Water conservation

Today there are only two ways to preserve water resources:

1. Preservation of existing fresh water reserves.

2. Creation of more advanced collectors.

The accumulation of water in reservoirs prevents its flow into the world's oceans. And storing water, for example, in underground cavities, allows you to protect water from evaporation. The construction of canals allows us to solve the issue of delivering water without it seeping into the ground. New methods of irrigating agricultural land are also being developed that make it possible to use wastewater.

But each of these methods has an impact on the biosphere. Thus, the reservoir system prevents the formation of fertile silt deposits. The canals impede the replenishment of groundwater. And water filtration in canals and dams is the main risk factor for swamps, which leads to disturbances in the planet’s ecosystem.

Today, the most effective measure for protecting water resources is considered to be the method of wastewater treatment. Various ways allow you to remove up to 96% of harmful substances from water. But this is often not enough, and the construction of more advanced treatment facilities often turns out to be economically unprofitable.

Water pollution problems

Population growth, development of production and agriculture - these factors have led to a shortage of fresh water for humanity. The share of polluted water resources is growing every year.

Main sources of pollution:

. Industrial wastewater;

. Wastewater from municipal routes;

. Drains from fields (when the water is oversaturated with chemicals and fertilizers);

. Disposal of radioactive substances in water bodies;

. Drains from livestock complexes (such water contains a lot of biogenic organic matter);

. Shipping.

Nature provides for the self-purification of reservoirs, which occurs due to the water cycle in nature, due to the life activity of plankton, irradiation ultraviolet rays, sedimentation of insoluble particles. But all these processes can no longer cope with the mass of pollution that human activity brings to the planet’s water resources.

Which can be used in economic activities.

The total volume of static water resources in Russia is estimated at approximately 88.9 thousand km 3 of fresh water, of which a significant part is concentrated in groundwater, lakes and glaciers, the estimated share of which is 31%, 30% and 17%, respectively. The share of Russian static fresh water reserves in global resources is on average about 20% (excluding glaciers and groundwater). Depending on the type of water sources, this indicator varies from 0.1% (for glaciers) to 30% (for lakes).

Dynamic reserves of water resources in Russia amount to 4,258.6 km 3 per year (more than 10% of the world figure), which makes Russia the second country in the world in terms of gross volume of water resources after Brazil. At the same time, in terms of water resource availability, Russia ranks 28th in the world ().

Russia has significant water resources and annually uses no more than 2% of their dynamic reserves; At the same time, a number of regions are experiencing water shortages, which is mainly due to the uneven distribution of water resources throughout the country - the most developed areas of the European part of Russia, where more than 80% of the population is concentrated, account for no more than 10–15% of water resources.

Rivers

The river network of Russia is one of the most developed in the world: there are about 2.7 million rivers and streams on the territory of the state.

Over 90% of rivers belong to the basins of the Arctic and Pacific oceans; 10% - to the Atlantic Ocean basin (Baltic and Azov-Black Sea basins) and closed inland basins, the largest of which is the Caspian Sea basin. At the same time, about 87% of the population of Russia lives in the regions belonging to the basins of the Caspian Sea and the Atlantic Ocean and the bulk of the economic infrastructure, industrial production capacities and productive agricultural land are concentrated.

The length of the vast majority of Russian rivers does not exceed 100 km; a significant part of them are rivers less than 10 km long. They represent about 95% of the more than 8 million km of the Russian river network. Small rivers and streams are the main element of the channel network of drainage areas. Up to 44% of the Russian population lives in their basins, including almost 90% of the rural population.

The average long-term river flow of Russian rivers is 4258.6 km 3 per year, most of this volume is formed on the territory of the Russian Federation and only a small part comes from the territory of neighboring states. River flow is distributed unevenly across Russian regions - the average annual figure varies from 0.83 km 3 per year in the Republic of Crimea to 930.2 km 3 per year in the Krasnoyarsk Territory.

The average in Russia is 0.49 km/km 2 , while the spread of values ​​of this indicator is uneven for different regions– from 0.02 km/km 2 in the Republic of Crimea to 6.75 km/km 2 in the Altai Republic.

A peculiarity of the structure of the Russian river network is the predominantly meridional direction of flow of most rivers.

The largest rivers in Russia

The question of which river is the largest in Russia can be answered in different ways - it all depends on what indicator is used to compare. The main indicators of rivers are basin area, length, average long-term flow. It is also possible to compare using indicators such as the density of the river network of the basin and others.

The largest water systems in Russia by basin area are the systems of the Ob, Yenisei, Lena, Amur and Volga; the total area of ​​the basins of these rivers is over 11 million km 2 (including the foreign parts of the Ob, Yenisei, Amur and, slightly, Volga basins).

About 96% of all lake water reserves are concentrated in the eight largest lakes of Russia (excluding the Caspian Sea), of which 95.2% is in Lake Baikal.

The largest lakes in Russia

When determining which lake is the largest, it is important to determine the indicator by which the comparison will be made.The main indicators of lakes are surface area and basin area, average and maximum depths, water volume, salinity, altitude, etc.The undisputed leader in most indicators (area, volume, basin area) is the Caspian Sea.

The largest mirror area is in the Caspian Sea (390,000 km2), Baikal (31,500 km2), Lake Ladoga (18,300 km2), Lake Onega (9,720 km2) and Lake Taimyr (4,560 km2).

The largest lakes by drainage area are the Caspian (3,100,000 km2), Baikal (571,000 km2), Ladoga (282,700 km2), Uvs-Nur on the border of Mongolia and Russia (71,100 km2) and Vuoksa (68,500 km 2).

The deepest lake not only in Russia, but also in the world is Baikal (1642 m). Next come the Caspian Sea (1025 m), lakes Khantaiskoye (420 m), Koltsevoe (369 m) and Tserik-Kol (368 m).

The deepest lakes are the Caspian (78,200 km 3), Baikal (23,615 km 3), Ladoga (838 km 3), Onega (295 km 3) and Khantayskoye (82 km 3).

The most salt Lake Russia – Elton (water mineralization in the lake in autumn reaches 525‰, which is 1.5 times more than the mineralization of the Dead Sea) in the Volgograd region.

Lakes Baikal, Lake Teletskoye and Uvs-Nur are included in the UNESCO World Natural Heritage List. In 2008, Lake Baikal was recognized as one of the seven wonders of Russia.

Reservoirs

On the territory of Russia, there are about 2,700 reservoirs in operation with a capacity of over 1 million m 3 with a total useful volume of 342 km 3, and more than 90% of their number are reservoirs with a capacity of over 10 million m 3.

The main purposes of using reservoirs:

• water supply;
• Agriculture;
• energy;
• water transport;
• fisheries;
• timber rafting;
• irrigation;
• recreation (rest);
• flood protection;
• watering;
• shipping.

The flow of rivers in the European part of Russia is most strongly regulated by reservoirs, where there is a shortage of water resources in certain periods. For example, the flow of the Ural River is regulated by 68%, the Don by 50%, and the Volga by 40% (reservoirs of the Volga-Kama cascade).

A significant share of regulated flow falls on the rivers of the Asian part of Russia, primarily Eastern Siberia - Krasnoyarsk Territory and Irkutsk region (reservoirs of the Angara-Yenisei cascade), as well as Amur region in the Far East.

The largest reservoirs in Russia

Due to the fact that the filling of reservoirs seriously depends on seasonal and annual factors, comparison is usually made based on the indicators achieved by the reservoir at (NFL).

The main tasks of reservoirs are the accumulation of water resources and the regulation of river flow, therefore, the important indicators by which the size of reservoirs are determined are full and. You can also compare reservoirs according to such parameters as FSL value, dam height, surface area, length coastline and others.

The largest reservoirs by their full volume are located in eastern regions Russia: Bratskoye (169,300 million m3), Zeyaskoye (68,420 million m3), Irkutskoye and Krasnoyarsk (63,000 million m3 each) and Ust-Ilimskoye (58,930 million m3).

The largest reservoirs in Russia in terms of useful volume are Bratskoye (48,200 million m3), Kuibyshevskoye (34,600 million m3), Zeyaskoye (32,120 million m3), Irkutsk and Krasnoyarsk (31,500 million m3 each) - also almost all located in the east; The European part of Russia is represented by only one reservoir, the Kuibyshevsky reservoir, located in five regions of the Volga region.

The largest reservoirs by surface area: Irkutsk on the river. Angara (32,966 km 2), Kuibyshevskoye on the river. Volga (6,488 km 2), Bratskoe on the river. Angare (5,470 km 2), Rybinskoye (4,550 km 2) and Volgogradskoye (3,309 km 2) on the river. Volga.

Swamps

Swamps play an important role in the formation of the hydrological regime of rivers. Being a stable source of river nutrition, they regulate floods and floods, extending them in time and height, and within their tracts contribute to the natural purification of river waters from many pollutants. One of important functions swamps are carbon sequestration: swamps sequester carbon and thus reduce the concentration of carbon dioxide in the atmosphere, weakening the greenhouse effect; Every year, Russian swamps sequester about 16 million tons of carbon.

The total area of ​​marshes in Russia is more than 1.5 million km 2, or 9% of the total area. Swamps are distributed unevenly across the country: greatest number swamps are concentrated in the northwestern regions of the European part of Russia and in the central regions of the West Siberian Plain; further south the process of marsh formation weakens and almost stops.

The most swampy region is the Murmansk region - swamps make up 39.3% of the total area of ​​the region. The least swamped areas are the Penza and Tula regions, the Republics of Kabardino-Balkaria, Karachay-Cherkessia, North Ossetia and Ingushetia, the city of Moscow (including new territories) - about 0.1%.

The areas of swamps range from several hectares to thousands of square kilometers. The swamps contain about 3,000 km 3 of static water reserves, and their total average annual flow is estimated at 1,000 km 3 /year.

An important element of swamps is peat - a unique combustible mineral of plant origin, which has... Russia's total peat reserves are about 235 billion tons, or 47% of world reserves.

The largest swamps in Russia

The largest swamp in Russia and one of the largest in the world is the Vasyugan swamp (52,000 km 2), located on the territory of four regions of the Russian Federation. – Salymo-Yugan swamp system (15,000 km 2), Upper Volga wetland complex (2,500 km 2), Selgon-Kharpinsky swamps (1,580 km 2) and Usinsk swamp (1,391 km 2).

The Vasyugan swamp is a candidate for inclusion in the list of UNESCO World Natural Heritage sites.

Glaciers

The total number of glaciers in the Russian Federation is over 8 thousand, the area of ​​island and mountain glaciers is about 60 thousand km 2, water reserves are estimated at 13.6 thousand km 3, which makes glaciers one of the largest accumulators of water resources in the country.

In addition, large reserves of fresh water are preserved in the Arctic ice, but their volumes are constantly decreasing and, according to recent estimates, this strategic fresh water reserve may disappear by 2030.

Most of Russia's glaciers are represented by the ice sheets of the islands and archipelagos of the Arctic Ocean - about 99% of Russia's glacial water resources are concentrated in them. Mountain glaciers account for slightly more than 1% of the glacial water supply.

The share of glacial feeding in the total flow of rivers originating from glaciers reaches 50% of the annual volume; The average long-term glacial runoff feeding the rivers is estimated at 110 km 3 /year.

Glacial systems of Russia

In terms of glaciation area, the largest are the mountain glacial systems of Kamchatka (905 km 2), the Caucasus (853.6 km 2), Altai (820 km 2), the Koryak Highlands (303.5 km 2) and the Suntar-Khayata ridge (201.6 km 2).

The largest reserves of fresh water are contained in the mountain glacial systems of the Caucasus and Kamchatka (50 km 3 each), Altai (35 km 3), Eastern Sayan (31.8 km 3) and the Suntar-Khayata ridge (12 km 3).

The groundwater

Groundwater accounts for a significant portion of fresh water reserves in Russia. In the face of increasing deterioration in quality surface waters fresh groundwater is often the only source of food supply for the population drinking water high quality, protected from contamination.

Natural groundwater reserves in Russia are about 28 thousand km 3 ; forecast resources, according to state monitoring of the state of the subsoil, are about 869,055 thousand m 3 /day - from approximately 1,330 thousand m 3 /day in the Crimean to 250,902 thousand m 3 /day in the Siberian Federal District.

The average provision of predicted groundwater resources in Russia is 6 m 3 /day per person.

HYDRAULIC SYSTEMS AND STRUCTURES

Hydraulic structures (HTS) are structures for the use of water resources, as well as for combating the negative effects of water. Dams, canals, dikes, shipping locks, tunnels, etc. GTS make up a significant part of the water management complex of the Russian Federation.

In Russia there are about 65 thousand hydraulic structures of water management, fuel and energy complexes and transport infrastructure.

To redistribute river flow from areas with excess river flow to areas with deficit, 37 large water management systems were created (the volume of transferred flow is about 17 billion m 3 /year); To regulate river flow, about 30 thousand reservoirs and ponds with a total capacity of more than 800 billion m 3 were built; To protect settlements, economic facilities and agricultural lands, over 10 thousand km of protective water barrier dams and shafts were built.

The reclamation and water management complex of federal property includes more than 60 thousand various hydraulic structures, including over 230 reservoirs, more than 2 thousand regulating waterworks, about 50 thousand km of water supply and discharge canals, over 3 thousand km of protective shafts and dams .

Transport hydrosystems include more than 300 navigable hydraulic structures located on inland waterways and are federally owned.

Hydraulic structures of Russia are under the jurisdiction of the Federal Agency for Water Resources, the Ministry of Agriculture of the Russian Federation, the Ministry of Transport of the Russian Federation, and the constituent entities of the Russian Federation. Some of the hydraulic structures are privately owned, over 6 thousand are ownerless.

Channels

Artificial riverbeds and canals are an important part of the water system of the Russian Federation. The main tasks of canals are flow redistribution, navigation, irrigation and others.

Almost all operating shipping canals in Russia are located in the European part and, with some exceptions, are part of the Unified Deep-Water System of the European part of the country. Some canals have historically been combined into waterways, for example, the Volga-Baltic and North Dvina, consisting of natural (rivers and lakes) and artificial (canals and reservoirs) waterways. There are also sea canals created to reduce the length of sea roads, reduce the risks and dangers of navigation, and increase the passability of seas. water bodies.

The bulk of economic (reclamation) canals with a total length of over 50 thousand km are concentrated in the Southern and North Caucasus Federal Districts, and to a lesser extent in the Central, Volga and southern Siberian Federal Districts. The total area of ​​reclaimed lands in Russia is 89 thousand km 2. Irrigation is of great importance for Russian agriculture, since arable land is located mainly in the steppe and forest-steppe zones, where agricultural yields fluctuate sharply from year to year depending on weather conditions and only 35% of arable land is in favorable conditions for moisture supply.

The largest channels in Russia

The largest waterways in Russia: the Volga-Baltic waterway (861 km), which includes, in addition to natural routes, the Belozersky, Onega bypass, Vytegorsky and Ladoga canals; White Sea-Baltic Canal (227 km), Volga-Caspian Canal (188 km), Moscow Canal (128 km), North Dvina Waterway (127 km), including Toporninsky, Kuzminsky, Kishemsky and Vazerinsky canals; Volga-Don Canal (101 km).

The longest economic canals in Russia that abstract water directly from water bodies (rivers, lakes, reservoirs): North Crimean Canal - , - a legal act regulating relations in the field of water use.

In accordance with Article 2 of the Water Code, the water legislation of Russia consists of the Code itself, other federal laws and laws of the constituent entities of the Russian Federation adopted in accordance with them, as well as by-laws adopted by executive authorities.

Water legislation (laws and regulations issued in accordance with them) is based on the following principles:

Part of the Russian legal system in the field of use and protection of water bodies are international treaties of Russia and ratified international conventions, such as the Convention on Wetlands (Ramsar, 1971) and the UN Economic Commission for Europe Convention on the Protection and Use of Transboundary Watercourses and International Lakes (Helsinki, 1992).

Water management

The central link in the field of use and protection of water resources is the Ministry of Natural Resources and Ecology of the Russian Federation (Ministry of Natural Resources of Russia), which exercises the authority to develop public policy and legal regulation in the field of water relations in Russia.

Russia's water resources are managed at the federal level by the Federal Agency for Water Resources (Rosvodresursy), which is part of the Russian Ministry of Natural Resources.

The powers of Rosvodresurs to provide public services and manage federal property in the regions are exercised by the agency's territorial divisions - basin water departments (BWU), as well as 51 subordinate institutions. Currently, there are 14 commercial banks operating in Russia, the structure of which includes departments in all regions of the Russian Federation. The exception is the regions of the Crimean Federal District - in accordance with the agreements signed in July - August 2014, part of the powers of Rosvodresursov was transferred to the relevant structures of the Council of Ministers of the Republic of Crimea and the Government of Sevastopol.

Management of regionally owned water resources is carried out by the relevant structures of regional administrations.

Management of federal facilities of the reclamation complex is under the jurisdiction of the Ministry of Agriculture of the Russian Federation (Department of Reclamation), water bodies of transport infrastructure - the Ministry of Transport of the Russian Federation (Federal Agency of Sea and River Transport).

State accounting and monitoring of water resources is carried out by Rosvodresursy; for maintaining the State Water Register - with the participation of the Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet) and the Federal Agency for Subsoil Use (Rosnedra); for maintaining the Russian Register of Hydraulic Structures - with the participation of the Federal Service for Environmental, Technological and Nuclear Supervision (Rostekhnadzor) and the Federal Service for Supervision of Transport (Rostransnadzor).

Supervision of compliance with legislation regarding the use and protection of water bodies is carried out by the Federal Service for Natural Resources Management (Rosprirodnadzor), and of hydraulic structures - by Rostechnadzor and Rostransnadzor.

According to the Water Code of the Russian Federation, the main unit of the management structure in the field of use and protection of water bodies is basin districts, however, today the existing structure of Rosvodresurs is organized on an administrative-territorial principle and in many ways does not coincide with the boundaries of basin districts.

Public policy

The basic principles of state policy in the field of use and protection of water bodies are enshrined in the Water Strategy of the Russian Federation until 2020 and include three key areas:

• guaranteed provision of water resources to the population and economic sectors;
• protection and restoration of water bodies;
• ensuring protection from negative impact water

As part of the implementation of the state water policy, the federal target program “Development of the water management complex of the Russian Federation in 2012–2020” (Federal Target Program “Water of Russia”) was adopted in 2012. The federal target program “Clean Water” for 2011–2017, the federal target program “Development of reclamation of agricultural lands in Russia for 2014–2020”, and target programs in Russian regions were also adopted.

Message on the topic

Water resources of the Earth

students

Ι course group 251(b)

Sazonova Daria

Kazan 2006.

1. General characteristics of water resources

2. Water balance of the Earth

3. Hydrosphere as a natural system

4. Oceans

5. Water sushi

6. Water management

7. Sources of water pollution

8. Measures for the protection and economical use of water resources

9. International Decade: “Water for Life”.

1. General characteristics of water resources.

The watery shell of the globe - oceans, seas, rivers, lakes - is called the hydrosphere. It covers 70.8% of the earth's surface. The volume of the hydrosphere reaches 1370.3 million km3, which is 1/800 of the total volume of the planet. 96.5% of the hydrosphere is concentrated in the oceans and seas, 1.74% in polar and mountain glaciers and only 0.45% in fresh waters. rivers, swamps and lakes.

The aquatic environment includes surface and groundwater. Surface water is mainly concentrated in the ocean, containing 1 billion 338 million km3 - about 98% of all water on Earth. The ocean surface (water area) is 361 million km2. It is approximately 2.4 times larger than the land area of ​​the territory, occupying 149 million km2. The water in the ocean is salty, and most of it (more than 1 billion km3) maintains a constant salinity of about 3.5% and a temperature of approximately 3.7° C. Noticeable differences in salinity and temperature are observed almost exclusively in the surface layer of water, as well as in the marginal and especially in Mediterranean seas. The content of dissolved oxygen in water decreases significantly at a depth of 50-60 meters.

Groundwater can be saline, brackish (less salinity) and fresh; existing geothermal waters have an elevated temperature (more than 30 ° WITH.). For production activities Humanity and its domestic needs require fresh water, the amount of which is only 2.7% of the total volume of water on Earth, and a very small share of it (only 0.36%) is available in places that are easily accessible for extraction. Most of the fresh water is contained in snow and freshwater icebergs, found in areas mainly in the Antarctic Circle. The annual global river flow of fresh water is 37.3 thousand km3. In addition, a part of groundwater equal to 13 thousand km3 can be used. Unfortunately, most of the river flow in Russia, amounting to about 5000 km3, occurs in the infertile and sparsely populated northern territories. In the absence of fresh water, salty surface or underground water is used, desalinating it or hyperfiltrating it: passing it under a high pressure difference through polymer membranes with microscopic holes that trap salt molecules. Both of these processes are very energy-intensive, so an interesting proposal is to use freshwater icebergs (or parts thereof) as a source of fresh water, which for this purpose are towed through the water to shores that do not have fresh water, where they are organized to melt. According to preliminary calculations by the developers of this proposal, obtaining fresh water will be approximately half as energy intensive as desalination and hyperfiltration. An important circumstance inherent in the aquatic environment is that it is mainly transmitted infectious diseases(approximately 80% of all diseases). However, some of them, for example, whooping cough, chickenpox, tuberculosis, are transmitted through the air. In order to combat the spread of diseases through aquatic environment The World Health Organization (WHO) has declared the current decade the decade of drinking water.

2. Water balance of the earth.

To imagine how much water is involved in the cycle, let’s characterize the different parts of the hydrosphere. More than 94% of it is made up of the World Ocean. The other part (4%) is groundwater. It should be taken into account that most of them belong to deep brines, and fresh water makes up 1/15 of the share. The volume of ice of the polar glaciers is also significant: when converted to water, it reaches 24 million km, or 1.6% of the volume of the hydrosphere. Lake water is 100 times less - 230 thousand km, and river beds contain only 1200 m of water, or 0.0001% of the entire hydrosphere. However, despite the small volume of water, rivers play a very important role: they, like groundwater, satisfy a significant part of the needs of the population, industry and irrigated agriculture. There is quite a lot of water on Earth. The hydrosphere makes up about 1/4180 of the mass of our planet. However, the share of fresh water, excluding water trapped in polar glaciers, accounts for a little more than 2 million km, or only 0.15% of the total volume of the hydrosphere.

3. Hydrosphere as a natural system

The hydrosphere is the discontinuous water shell of the Earth, a collection of seas, oceans, continental waters (including groundwater) and ice sheets. Seas and oceans occupy about 71% of the earth's surface, containing about 96.5% of the total volume of the hydrosphere. The total area of ​​all inland water bodies is less than 3% of its area. Glaciers account for 1.6% of the water reserves in the hydrosphere, and their area is about 10% of the area of ​​the continents.

The most important property of the hydrosphere is the unity of all types of natural waters (the World Ocean, land waters, water vapor in the atmosphere, groundwater), which occurs in the process of the water cycle in nature. The driving forces behind this global process The thermal energy of the Sun and the force of gravity entering the Earth's surface serve to ensure the movement and renewal of natural waters of all types.

Under influence solar heat Water in nature undergoes a continuous cycle. Water vapor, which is lighter than air, rises to the upper layer of the atmosphere, condenses into tiny droplets, forming clouds, from which water returns to the surface of the earth in the form of precipitation - rain, snow. The water that falls on the surface of the globe partially arrives

directly into natural reservoirs, partially collected in the upper layer

soils, forming surface and groundwater.

Evaporation from the surface of the World Ocean and from the surface of land is the initial link in the water cycle in nature, ensuring not only the renewal of its most valuable component - fresh land waters, but also their high quality. An indicator of the activity of water exchange in natural waters is high speed their renewal, although different natural waters are renewed (replaced) at different rates. The most mobile agent of the hydrosphere is river water, the renewal period of which is 10-14 days.

The predominant part of hydrosphere waters is concentrated in the World Ocean. The world ocean is the main closing link of the water cycle in nature. It releases most of the evaporated moisture into the atmosphere. Aquatic organisms inhabiting the surface layer of the World Ocean provide the return of a significant part of the planet’s free oxygen to the atmosphere.

The huge volume of the World Ocean indicates the inexhaustibility of natural resources planets. In addition, the World Ocean is a collector of river waters on land, receiving about 39 thousand m3 of water annually. The pollution of the World Ocean that has emerged in certain areas threatens to disrupt the natural process of moisture circulation in its most critical link - evaporation from the ocean surface.

4. World Ocean.

The average depth of the World Ocean is 3700 m, the greatest is 11022 m (Mariana Trench). The volume of water in the World Ocean, as mentioned above, is cubic. km.

Almost all substances known on Earth are dissolved in sea water, but in different quantities. Most of them are difficult to detect due to their low content. The main part of the salts dissolved in sea water are chlorides (89%) and sulfates (almost 11%), significantly less carbonates (0.5%). Salt ( NaCl) gives water a salty taste, magnesium salts (MqCl) - bitter. The total amount of all salts dissolved in water is called salinity. It is measured in thousandths - ppm (%o).

The average salinity of the World Ocean is about 35%.

The salinity of ocean water depends primarily on the ratio of precipitation and evaporation. River waters and water from melting ice reduce the salinity. IN open ocean The distribution of salinity in the surface layers of water (up to 1500 m) is zonal. In the equatorial zone, where there is a lot of precipitation, it is low, in tropical latitudes it is high.

Inland seas differ noticeably in salinity. The salinity of water in the Baltic Sea is up to 11%o, in the Black Sea - up to 19%o, and in the Red Sea - up to 42%o. This is explained by the different ratio of inflow (precipitation, river runoff) and outflow (evaporation) of fresh water, i.e., climatic conditions. Ocean - heat regulator

The highest temperature at the surface of the water in the Pacific Ocean is 19.4 ° C; Indian Ocean has 17.3 °C; Atlantic - 16.5 °C. At these average temperatures, water in the Persian Gulf regularly reaches 35°C. As a rule, water temperature decreases with depth. Although there are exceptions due to the rise of deep warm waters. An example would be West Side The Arctic Ocean, where the Gulf Stream invades. At a depth of 2 km throughout the entire waters of the World Ocean, the temperature usually does not exceed 2-3 °C; in Northern Arctic Ocean she's even lower.

The world's oceans are a powerful heat accumulator and regulator of the Earth's thermal regime. If there were no ocean, the average temperature of the Earth's surface would be - 21 °C, that is, it would be 36 ° lower than what actually exists.

Currents of the World Ocean

Ocean waters are in constant motion under the influence of various forces: cosmic, atmospheric, tectonic, etc. The most pronounced are surface sea currents, mainly of wind origin. But 3 currents are very common, arising due to different mass densities. Currents in the World Ocean are divided according to their prevailing direction into zonal (going to the west and east) and meridional (carrying water to the north and south). Currents moving towards neighboring, more powerful currents are called countercurrents. Equatorial currents (along the equator) are specially distinguished. Currents that change their strength from season to season, depending on the direction of the coastal monsoons, are called monsoon currents.

The most powerful in the entire World Ocean is the Circumpolar, or Antarctic, circular current, caused by strong and stable westerly winds. It covers a zone 2500 km wide and kilometer deep, carrying about 200 million tons of water every second. For comparison, the world's largest river, the Amazon, carries only about 220 thousand tons of water per second.

In the Pacific Ocean, the strongest is the Southern Trade Wind Current, moving from east to west, at a speed of 80-100 miles per day. To the north of it there is a countercurrent, and even further north there is the Northern Trade Wind Current from east to west. Knowing the direction of the currents, local residents have long used them for their movements. Following them, T. Heyerdahl used this knowledge for his famous trip to the Kon-Tiki. There are analogues of trade wind (literally “favorable for movement”) currents and countercurrents in the Indian and Atlantic oceans.

Of the meridional currents, the most famous are the Gulf Stream and Kuroshio, which transport 75 and 65 million tons of water per second, respectively.

Many areas of the World Ocean (the western shores of North and South America, Asia, Africa, Australia) are characterized by upwelling, which can be caused by wind driven surface waters from the coast. Rising deep waters often contain large amounts of nutrients, and upwelling sites are associated with a zone of high biological productivity.

The role of the ocean in people's lives

It is difficult to overestimate the role of the World Ocean in the life of mankind. It largely determines the face of the planet as a whole, including its climate and the water cycle on Earth. The ocean contains vital waterways connecting continents and islands. Its biological resources are colossal. The World Ocean is home to more than 160 thousand species of animals and about 10 thousand species of algae. Annually reproduced quantity commercial fish estimated at 200 million tons, of which approximately 1/3 is caught. More than 90% of the world's catch comes from the coastal shelf, especially in the temperate and high latitudes of the Northern Hemisphere. The share of the Pacific Ocean in the world catch is about 60%, the Atlantic - about 35%.

The shelf of the World Ocean has huge reserves of oil and gas, large reserves of iron-manganese ores and other minerals. Humanity is just beginning to use the energy resources of the World Ocean, including tidal energy. The World Ocean accounts for 94% of the volume of the hydrosphere. The desalination of sea waters is associated with the solution to many water problems of the future.

Unfortunately, humanity does not always wisely use the natural resources of the World Ocean. In many areas its biological resources have been depleted. A significant part of the water area is polluted by waste anthropogenic activities, primarily petroleum products.

Land waters include waters, rivers, lakes, swamps, glaciers. They contain 3.5% of the total waters of the hydrosphere. Of these, only 2.5% are fresh waters.

Groundwater is found in the rock strata of the upper part of the earth's crust in liquid, solid and vapor states. The bulk of them is formed due to the seepage of rain, melt and river water from the surface.

According to the conditions of occurrence, groundwater is divided into:

1) soil, located in the uppermost soil layer;

2) soil, lying on the first permanent waterproof layer from the surface;

3) interstratal, located between two impermeable layers;

The latter are often pressure and are then called artesian.

Groundwater feeds rivers and lakes.

Rivers are constant water streams flowing in the depressions they themselves develop - channels.

The most important characteristic of rivers is their nutrition. There are four sources of nutrition: snow, rain, glaciers and underground.

The regime of the rivers largely depends on the feeding of rivers, i.e. changes in the amount of water flow according to the seasons of the year, fluctuations in level, changes in water temperature. The water regime of a river is characterized by water flow and runoff. Flow rate is the amount of water passing through the cross-section of the flow in one second. Water consumption over a long period of time - a month, a season, a year - is called runoff. The volume of water that rivers carry on average per year is called their water content. The most abundant river in the world is the Amazon, at its mouth the average annual water flow is 220,000 cubic meters. m./s. In second place is Congo (46,000 cubic meters per second), then the Yangtze. In our country, the most abundant river is the Yenisei (19,800 cubic meters per second). Rivers are characterized by a very uneven distribution of flow over time. Most rivers in Russia carry 60-70% of the volume of water in a relatively short period spring flood. At this time, melt water flows over the frozen and well-moistened surface of the catchment areas with minimal losses due to filtration and evaporation.

It is during the flood period that rivers most often overflow their banks and flood the surrounding areas. In summer and winter, there is usually low water - low water, when rivers are fed by groundwater, the resources of which are also significantly replenished in spring period. In summer, most of the precipitation is spent on evaporation; only a small part of the precipitation reaches the groundwater level and, especially, reaches the rivers. In winter, precipitation accumulates in the form of snow. Only in autumn there are small floods on Russian rivers.

The rivers of the Far East and the Caucasus differ from the lowland rivers of Russia in their hydrological regime. The first ones flood in the fall - during the monsoon rains; On Caucasian rivers, maximum water flows are observed in the summer, when high-mountain glaciers and snowfields melt.

River flow varies from year to year. Low-water and high-water periods often occur when the river is characterized by low or, on the contrary, high water content. For example, in the 1970s, there was low water on the Volga, due to which the level of the endorheic Caspian Sea, for which the Volga is the main supplier of water, quickly fell. Since 1978, a phase of increased humidity began in the Volga basin, its runoff annually began to exceed the long-term average, and the level of the Caspian Sea began to rise, as a result of which coastal areas were flooded. Most of Russia's rivers are covered with ice every year. The duration of freeze-up in northern Russia is 7-8 months (from October to May). The opening of rivers from ice - ice drift - is one of the most impressive spectacles, often accompanied by flooding.

Rivers have played an outstanding role in the history of mankind; the formation and development of human society is associated with them. Since historical times, rivers have been used as routes of communication, for fishing and fish farming, timber rafting, field irrigation and water supply. People have long settled along the banks of rivers - this is confirmed by folklore, in which the Volga is called “mother”, and the Amur is called “father”. The river is the main source of hydropower and the most important transport route. Rivers are of great aesthetic and recreational importance as an integral element of the environment. The widespread involvement of rivers in economic circulation has led to the complete transformation of many of them. The flow of rivers such as the Volga, Dnieper, and Angara is largely regulated by reservoirs. Many of them, especially those occurring in the southern regions where the need for irrigation is great, are dismantled for irrigation needs. For this reason, the Amu Darya and Syr Darya practically no longer flow into the Aral Sea, and it is rapidly drying up.

One of the most negative results of anthropogenic impact on rivers is their massive pollution by sewage and other waste from economic activities. The threat of qualitative depletion of river water resources can be avoided if a set of water management measures is implemented, including not only traditional wastewater treatment, but also such drastic measures as changing production technology in order to significantly reduce water consumption and waste generation.

Lakes are natural bodies of water in depressions of land (basins), filled within the lake bowl (lake bed) with heterogeneous water masses and without a one-way slope. Lakes are characterized by the absence of a direct connection with the World Ocean. Lakes occupy about 2.1 million km2, or almost 1.4% of the land area. This is approximately 7 times the surface of the Caspian Sea, the largest lake in the world.

A swamp is an area of ​​land with excessive stagnant soil moisture, overgrown with moisture-loving vegetation. Swamps are characterized by the accumulation of undecomposed plant debris and the formation of peat. Swamps are distributed mainly in the Northern Hemisphere, especially in lowland areas where permafrost soils are developed, and cover an area of ​​about 350 million hectares

Glaciers are moving natural accumulations of ice of atmospheric origin on the earth's surface; are formed in those areas where more solid atmospheric precipitation is deposited than melts and evaporates. Within the glaciers, areas of feeding and ablation are distinguished. Glaciers are divided into terrestrial, shelf and mountain ice sheets. The total area of ​​modern glaciers is approx. 16.3 million km2 (10.9% land area), total ice volume approx. 30 million km3.

6. Water resources management.

One of the directions for solving water problems is to attract currently underutilized water resources from desalinated waters of the World Ocean, groundwater and glacier waters for the purpose of water supply. Currently, the share of desalinated water in the total volume of water supply in the world is small - 0.05%, which is explained by the high cost and significant energy intensity of desalination processes. Even in the United States, where the number of desalination plants has increased 30 times since 1955, desalinated water accounts for only 7% of water consumption.

In Kazakhstan, in 1963, the first pilot industrial desalination plant came into operation in Aktau (Shevchenko). Due to the high cost, desalination is used only where surface or groundwater fresh water resources are completely absent or extremely difficult to access, and their transportation is more expensive compared to desalination.

increased mineralization directly on site. In the future, water desalination will be carried out in a single technical complex with the extraction of useful components from it: sodium chloride, magnesium, potassium, sulfur, boron, bromine, iodine, strontium, non-ferrous and rare metals, which will increase the economic efficiency of desalination plants.

An important reserve of water supply is groundwater. Fresh groundwater is of greatest value to society, accounting for 24% of the volume of the fresh part of the hydrosphere. Brackish and saline groundwater can also serve as a reserve for water supply when used in a mixture with fresh water or after its artificial desalination. Factors limiting underground water intake include:

1) the unevenness of their distribution over the territory of the earth;

2) difficulties in processing saline groundwater;

3) rapidly decreasing rates of natural regeneration with

increasing the depth of aquifers.

The utilization of water in the solid phase (ice, ice sheets) is assumed, firstly, by increasing the water yield of mountain glaciers, and secondly, by transporting ice from the polar regions. However, both of these methods are practically difficult to implement and the environmental consequences of their implementation have not yet been studied.

Thus, on modern stage development opportunities to attract additional volumes of water resources are limited. It should also be noted that the distribution of water resources across the globe is uneven. The highest availability of river and underground runoff resources is in equatorial belt South America and Africa. In Europe and Asia,

Where 70% of the world's population lives, only 39% of river waters are concentrated. The largest rivers in the world are the Amazon (annual flow 3780 km3), Congo (1200 km3), Mississippi (600 km3), Zamberi (599 km3), Yangtze (639 km3), Irrawaddy (410 km3), Mekong (379 km3), Brahmaputra ( 252 km3) . In Western Europe, the average annual surface runoff is 400 km3, including about 200 km3 in the Danube, 79 km3 on the Rhine, 57 km3 on the Rhone. The largest lakes in the world are the Great American Lakes (total area - 245 thousand km3), Victoria (68 thousand km3), Tanganyika (34 thousand km3), Nyasa (30.8 thousand km3).

The Great American Lakes contain 23 thousand km3 of water, the same as Lake Baikal. To characterize the distribution of hydro resources, the volume of total river flow per unit of territory (1 km3) and population is calculated. Per 1 million inhabitants of the USSR there is 5.2 km3 of total sustainable flow (including that regulated by reservoirs) versus 4 km3 for the total

globe; 19 km3 of total river flow versus 13 km3; 4.1 sustainable underground flow versus 3.3 km3. The average water supply per 1 km2 is 212 thousand m3 in the CIS, and 278 thousand m3 on the globe. The main methods of water resource management are the creation of reservoirs and territorial transfer of flow.

7. Sources of water pollution.

The Earth's hydrosphere is of great importance in the exchange of oxygen and carbon dioxide with the atmosphere. Oceans and seas have a softening, regulating effect on air temperature, accumulating heat in summer and releasing it to the atmosphere in winter. The circulation and mixing of warm and cold waters occurs in the ocean. The biomass of vegetation of the oceans and seas is many times

less than sushi, but the animal biomass is at least an order of magnitude greater. Oceans and seas absorb carbon dioxide. The hydrosphere is an important source of food for humans and other land inhabitants. The fish catch, which amounted to 3 million tons per year at the beginning of this century, currently reaches 80 million tons. This growth is associated with the progress of technology, the widespread use of special trawlers, seiners with hydroacoustic devices for detecting accumulations of fish, equipment for impact on her

light, electric current.

Fish pumps, nylon nets, trawling, freezing and canning of fish on board appeared. As a result of the increased catch, its composition deteriorated, the specific gravity of herring decreased,

Sardines, salmon, cod, flounder, halibut and an increased proportion of tuna, mackerel, sea ​​bass and bream. With significant investments, it is realistically possible to increase seafood catches to 100-130 million tons. These figures include, for example, krill, small crustaceans, the reserves of which are huge in the southern seas. Krill contains protein; these crustaceans can be used for food and other purposes. A large number of the fish being caught goes. Not for food, but for food

livestock or processed into fertilizers. Over a number of years, especially post-war, a significant part of the whales have been exterminated, and some of their species are on the verge of complete destruction. By international agreement, further whale catches are limited. The destruction of the inhabitants of the oceans and seas as a result of their unreasonable fishing raises the question of the advisability of the transition from extensive fishing to artificial fish farming. In this regard, we can recall the transition from hunting and collecting fruits and roots in the earlier stages of social development to the breeding of animals and plants.

8. Measures for the protection and economical use of water resources.

Serious measures are being taken to prevent the growing pollution of water bodies by wastewater. Wastewater is water discharged after use in human household and industrial activities. By their nature, pollution is divided into mineral, organic, bacteriological and biological. The criterion for the harmfulness of wastewater is the nature and degree of limitation of water use. The quality of natural waters in Kazakhstan is standardized in places of water use. The developed standard indicators are extremely permissible concentrations the content of harmful substances in the water of water bodies for various purposes - relates to the composition of water in reservoirs, and not to the composition of wastewater.

In accordance with the Regulations on state accounting of waters and their

In use (1975), the primary accounting of wastewater discharged into water bodies is carried out by water users themselves. This control is carried out unsatisfactorily by the majority of water users. This is evidenced by the fact that only 20% of discharged wastewater is controlled by hydraulic engineering

equipment, and the rest - by indirect methods. Currently, a transition to a system of maximum permissible emissions (MPE) standards is underway. MAC values ​​are determined for each specific emission source in such a way that total emissions from all sources in the region do not exceed the MAC standard. The use of MPE standards will facilitate planning and control of environmental activities, increase

responsibility of the enterprise for compliance with environmental requirements will eliminate conflict situations. Of the total amount of wastewater, 69% is conditionally clean, 18% is polluted and 13% is purified to standard standards. There are no strict criteria for dividing industrial wastewater into standard-treated, polluted and conditionally clean. Untreated wastewater requires repeated dilution with clean

water. The oil refining, pulp and paper and chemical industries are especially polluting. Standard purified water

The main market method of regulating environmental activities is payment for pollution. There are two types of fees per unit of emissions and fees for the use of public wastewater treatment plants. The level of payment in the first case is determined by the desired quality of the environment. The mechanism of such a board automatically ensures optimal resource allocation. The fee for the use of treatment facilities includes

a basic fee for the discharge of standard wastewater, an additional fee for excess discharge, a fee for water transportation and a fee for service by the water inspectorate. To assess river water pollution, a conditional pollution indicator is used. The size of the fee depends on the age of the treatment facilities, the ability of reservoirs to self-purify, and the composition of the wastewater. The board mechanism is most effective in conditions of pure competition, when each firm strives to minimize costs per unit

release. Under conditions of monopolies, firms may not set themselves such a goal, therefore, in monopolized industries, methods of direct administrative regulation gain advantages.

10. International Decade "Water for Life"

4,000 children die every day due to diseases caused by undrinkable water; 400 million children do not have even the bare minimum of safe water they need to live; As many as 2.6 billion people live without sanitation - all of which challenges the UN's fight for clean water.

The United Nations Children's Fund (UNICEF) has highlighted the fact that a lack of clean water is responsible for at least 1.6 million of the 11 million avoidable child deaths each year. Almost three children die every minute due to diseases caused by undrinkable water, such as diarrhea and typhoid fever. IN African countries In the sub-Saharan region, where one in five children die before their fifth birthday, 43% of children drink unsafe water, risking illness and death with every sip.

The Office of the United Nations High Commissioner for Refugees (UNHCR) spoke about the situation in Zhegriyad - the “Valley of Death” in Somalia. It got its name because people die of thirst here every year, primarily drivers whose trucks or cars break down on the way to Djibouti.

This is just a small part of the challenge facing UNHCR, an organization that tries to help 17 million people in more than 116 countries. In Tindouf, Algeria, a project is currently underway to improve the water supply of the Smara camp in the middle of the Sahara Desert, where tens of thousands of refugees from Western Sahara live.

In another camp in eastern Chad, where more than 200,000 refugees are fleeing conflict in Sudanese Darfur, UNHCR continues to work to provide water to refugees by delivering water, drilling boreholes, digging wells and helping high technology is looking for additional sources of water.

On March 22, 2005, the UN celebrated World Water Day, proclaiming Messrs. International Decade “Water for Life”. Data on the scale of the problem and the stories of specific people is what, in addition to the speeches of UN leaders, brings home just how difficult it will be for the world to meet one of the Millennium Development Goals: to halve the number of people living in poverty by 2015. clean drinking water and minimum sanitation conditions.

List of used literature:

1. Geography. A complete exam preparation course. Moscow. AST-press; 2004

2. , “Environmental protection”

3. B. Nebel “Environmental Science” Moscow. "Science" 2002

4. Great Soviet Encyclopedia. Moscow. "Soviet Encyclopedia", 1972

Introduction

Water is the only substance that is present in nature in liquid, solid and gaseous states. Meaning liquid water varies significantly depending on location and application. Fresh water is more widely used than salt water. Over 97% of all water is concentrated in the oceans and inland seas. Another about 2% comes from fresh water contained in cover and mountain glaciers, and only less than 1% comes from fresh water in lakes and rivers, underground and groundwater.

The harmonious cooperation of man with nature, his rational social activity, which regulates and controls the exchange of substances between nature and society, has become one of the most pressing tasks in the modern era. Increase material goods society, which is accompanied by anthropogenic pressure, has led to serious environmental pollution. This is especially noticeable in the field of natural resource use.

General characteristics of the world's water resources

Planet Earth has a colossal volume of water, about 1.5 billion cubic meters. km. However, 98% of this volume is the salty waters of the World Ocean, and only 28 million cubic meters. km - fresh waters. Since technologies for desalination of salty sea waters are already known, the waters of the World Ocean and salt lakes can be considered as potential water resources, the use of which in the future is quite possible. Annually renewable reserves of fresh water are not so large; according to various estimates, they range from 41 to 45 thousand. cube km (full river flow resources). The world economy uses about 4-4.5 thousand cubic meters for its needs. km, which is equal to approximately 10% of the total water supply, and, therefore, subject to the principles of rational water use, these resources can be considered as inexhaustible. However, if these principles are violated, the situation can sharply worsen, and even on a planetary scale there may be a shortage of clean fresh water. In the meantime, the natural environment annually “gives” humanity 10 times more water than he needs to satisfy a wide variety of needs.

Water resources are of utmost importance economic importance. They are considered inexhaustible, but in their placement they are directly and indirectly influenced by other components natural complex, as a result, they are characterized by great variability and uneven distribution.

The uniqueness of natural resources is determined mainly by the continuous mobility of water participating in the cycle. In accordance with their place in this cycle, water on Earth appears in various forms that have unequal value in terms of satisfaction human needs, i.e. as resources.

Water resources are characterized by strong regime variability in time, ranging from daily to secular fluctuations of each source. The complex interaction of many factors gives runoff fluctuations the character of a random process. Therefore, calculations related to water resources inevitably take on a probabilistic, statistical nature.

Water resources differ greatly complexity of territorial forms. Many features of water resources arise from unique ways of using them. With rare exceptions, water is not used directly to create any materials, converted into another substance and permanently removed from natural cycle, as happens with mineral or forest resources. On the contrary, during use, water resources either remain in natural flow channels (water transport, hydropower, fisheries, etc.) or return to the water cycle (irrigation, all types of economic and domestic water supply). Therefore, in principle, the use of water resources does not lead to their exhaustion.

However, in practice the situation is more complicated. Use of water for dissolution and transportation useful substances or waste, cooling of heat-generating units or as a coolant leads to qualitative changes (pollution, heating) of waste water and (when discharged) the water supply sources themselves. When water is used for irrigation, it is only partially (and often in a changed qualitative state) returned to local drainage channels; mainly, as a result of evaporation from the soil, it goes into the atmosphere, being included in the ground phase of the cycle in other, usually very remote, areas.

Due to the rapid increase in water consumption as water shortages arise in more and more areas, the situation has begun to change. There is a need for a mechanism to regulate the use of limited water resources and their distribution between consumers - economic or administrative.

Characteristic possibility of multi-purpose use water resources, carried out by many industries that have specific requirements for their quantity and quality. Since in most cases the same water sources serve to satisfy different needs, certain water management combinations (complexes) are formed in river basins (spontaneously or systematically), including all consumers and users of a given basin.

One of the main water consumers - irrigated agriculture. By withdrawing significant volumes of water from sources of surface or underground water resources, it essentially turns them into agricultural resources, artificially replenishing the water consumption for transpiration that is insufficient for the normal development of cultivated plants. The next type of water consumption is water supply, covering a wide range of different uses of water resources. Common property for them there is a high proportion of irrecoverable losses. The differences are determined by the specific requirements of water consuming industries.

The discharge of sewage and industrial wastewater is directly related to municipal and industrial water supply. Their volume is proportional to the scale of water consumption. Depending on the role of water in the technological process, a significant portion comes from contaminated wastewater. This creates a problem of qualitative depletion of water resources that is becoming increasingly worse as the scale of production grows. In this problem, two aspects can be distinguished: the actual qualitative and the quantitative. In the economic aspect, this is expressed either in additional costs that are necessary to process water and bring it to the required condition by other consumers, or in losses resulting from the inability to use this source of water resources due to its pollution.

However, in essence, the specific measures included in this concept actually represent water supply to waterless or low-water areas. The latter circumstance is associated with the allocation of water supply to a special water management task, usually attributed to a certain area, although in fact it means the provision of water to specific points - centers of water consumption.

Hydropower imposes its own specific quality requirements on water resources. In addition to water content, which determines the total value of the energy potential, the water flow regime - the change in water flow over time - is of great importance.

Specific form of energy use - development of underground thermal water resources, serving to some extent as fuel, but one that must be consumed immediately, at the place of its extraction from the bowels.

Water transport has virtually no effect on other uses of water resources (except for relatively weak and easily removable pollution and the impact of waves raised by ships on the shores).

Fisheries uses water resources as a means of subsistence for another type of natural resource - biological. In this it is similar to irrigated agriculture, but unlike it, it is not associated with the withdrawal of water from natural sources.

One of the types of water consumption is often considered watering.

It should be noted that water resources are used for rest and treatment. This function is becoming increasingly important, although neither its technical requirements nor its economic basis have yet been defined. As a rule, each water management complex includes different types of water resource use and consumption. However, the set of types of use and their quantitative ratio vary widely. It follows from this great option organization of water management complexes. Differences in the structure of individual options are determined by natural features each basin and the economic structure of the corresponding region.

Water resources are fresh water suitable for consumption contained in rivers, lakes, glaciers, and underground horizons. Atmospheric vapors, ocean and sea salt waters are not yet used in the economy and therefore constitute potential water resources.

The importance of water in the world economy is difficult to overestimate. It is used in almost all sectors of the economy: in the energy sector, for irrigation of agricultural land, for industrial and municipal water supply. Often water sources serve not only for water intake purposes, but are also objects of economic use as transport routes, recreational areas, and reservoirs for the development of fisheries."

The volume of water contained in rivers, lakes, glaciers, seas and oceans, in underground horizons and in the atmosphere reaches almost 1.5 billion km 3. This is the water potential of our planet. However, 98% of the total water volume is salt water and only 28.3 million km 3. "for fresh water (with mineralization less than 1 g/l). In general, the volume of fresh water is a very significant value, especially when compared with modern global consumption, which reached 4-4.5 thousand cubic meters per year in the 90s It would seem that humanity does not need to worry about fresh water, since there is 10,000 times more of it than required. But the bulk of fresh water (almost 80%) is water from glaciers, snow covers, underground ice permafrost, deep layers of the earth's crust. Currently they are not used and are considered as potential water resources. Their future development depends not only on improving water extraction techniques and its economic feasibility, but also on solving the often negative unpredictable environmental problems that unexpectedly arise when using unconventional water sources.

The one-time volume of river waters on land is small - it is estimated at only 2000 km3, but thanks to the cycle, rivers annually discharge about 40-41 thousand km3 into the World Ocean. According to calculations by M.I. Lvovich (1986), the total river flow is 38,830 km3. In addition, 3000 km3 flows from land to the ocean. fresh water in the form of ice and melt water from the glaciers of Greenland and Antarctica and 2400 km3. - in the form of underground flow (bypassing rivers). Thus, about 44.5 thousand cubic meters of water enters the ocean from land annually.

So, the volume of fresh water reserves in the world is small in general and is distributed very unevenly across the continents. In addition, surface runoff is subject to sharp seasonal fluctuations, reducing the possibility of its economic development.

Figure 1 shows the availability of river flow resources per capita (thousand cubic meters/year) by continent and part of the world.

Figure 1. Availability of river flow resources per capita.

The available water resources of rivers are made up of two categories - surface and underground flow. The most economically valuable is the underground component of the runoff, since it is less susceptible to seasonal or daily fluctuations in volume. In addition, groundwater is less likely to become polluted. They form the predominant part of the “sustainable” flow, the development of which does not require the construction of special control devices. The surface component of runoff includes flood and flood waters, which usually flow quickly along river beds.

In areas with seasonal atmospheric humidification, the ratio of water flows in river beds in dry and wet periods of the year can reach 1:100 and even 1:1000. In such areas, when developing surface runoff, it is necessary to construct reservoirs for seasonal or even long-term regulation.

The greater the proportion of the sustainable component of the flow, the higher the economic value or quality of the water resource potential of a region. Its value is quantitatively determined by the volume of underground flow and low-water channel flow. The world's total available water resources are estimated; 41 thousand cubic km per year, of which only 14 thousand cubic km. constitute their stable part (M. I. Lvovich, 1986).

Rice. 2. Average water flow of the largest rivers (m3/s)

Water balance and its categories. In modern economies, the main consumers of water are industry, agriculture and public utilities. They withdraw certain volumes of water from natural and artificial reservoirs for their needs, which constitute water intake. Thus, according to new calculations by M.I. Lvovich, the total water intake in 2000 will be 4780 cubic km.

During use, a certain amount of withdrawn water is lost through evaporation, seepage, technological binding, etc., and the scale of such consumption varies among different consumers. For small areas, these losses are considered as irrevocable. Their volume is most significant (up to 80-90%) for agricultural use. In some industries, schemes for closed or multiple water use have been developed and continue to be intensively improved, with the help of which both the volume of water intake in general and the amount of irretrievable losses are significantly reduced.

Utilities and agriculture, industry; and hydropower have different requirements for water quality. Water used for drinking purposes and in some industries (food, chemical, etc.) should have the highest sanitary and taste qualities. Metallurgical or, for example, mining production can use water Low quality, use circulating water supply systems.

Repeated use of the same volume of water reduces water intake, but forces one more category to be introduced into the water balance - water consumption - the total volume of water used by a given sector of the economy over a certain period of time.

In the public utilities sector, water consumption and water intake are equal, because recycling water supply in this industry is practically not carried out at the current level. In industry, water intake is much lower than water consumption due to the use of closed water supply cycles, when water is taken from sources only to compensate for irretrievable losses.

In agriculture, water consumption can also quantitatively exceed water intake from sources, since organic wastewater from urban municipal systems or partially treated wastewater from some industrial enterprises is often used for irrigation.

The structure of water intake and water consumption, i.e. the distribution of withdrawn volumes of water between consumers, can vary significantly from area to area, reflecting general level economic development of the economy, and its specialization, and, to a large extent, the specifics natural conditions. Any economic use water by various consumers is accompanied by the appearance waste water or effluent. They are overloaded with a huge amount of foreign substances of industrial, agricultural or municipal origin, changing the physical and chemical properties of the water mass. Even if the most advanced waste water treatment methods known to modern science are used (mechanical, chemical, biological), to dilute 1 m 3 of such wastewater it is necessary to spend at least 8-10 m 3 of pure natural water. If untreated wastewater is discharged, the water consumption increases several times. Currently, in the world, among household wastewater discharged into natural reservoirs, the categories of weakly treated or generally untreated water prevail.

As a result, crisis phenomena affect not only areas that were initially depleted in water reserves, but also those where there are favorable natural conditions for the formation of significant volumes of water. Uncontrolled technogenic transformation of the quality of water geosystems poses the threat of “water famine” to the economies of such countries.

World water consumption. According to estimates (Lvovich, 1986), in the early 80s, about 4.5 thousand cubic kilometers were used in the world for various economic needs, and in 1987 - 3.3 thousand cubic kilometers. water. This volume represents almost 8% of the total total flow from the land surface to the ocean. It can be concluded that, on the whole, the world economy is fully provided with fresh water in the amount necessary to meet its needs. However, attention should be paid to the very sharp, almost uncontrollable increase in underconsumption in the second half of the 20th century. Over the past 80 years, agricultural water use has increased 6 times, municipal water use 7 times, industrial use 20 times, and general use 10 times.

For individual components of the world's water balance modern period develops as follows.

Municipal water supply. In the early 80s, about 200 km3 were spent on the needs of the population, and at the same time 100 km3. was lost forever. In 1990, more than 300 cubic kilometers were withdrawn for these purposes. Water consumption standards per person average 120-150 liters per day. In reality they fluctuate a lot. In cities in industrialized countries, water consumption is especially high. For example, in European countries it rises to 300-400 l/day. In cities of developing countries located in subarid or arid regions, standards are reduced to 100-150 l/day. A rural resident uses much less water. In humid areas in developed countries, it consumes up to 100-150 liters of water per day, and in dry tropical areas - no more than 20-30 liters.

According to the data World Organization Health (WHO) currently more than 1.5 billion people in the world are not provided with clean, safe water, and by 2000 their number could reach 2 billion people.

Industrial water supply. The unique properties of water as a natural body allow it to be used very widely in a variety of industries. It is used for energy purposes, as a solvent, coolant, and a component of many technological processes. The water intensity of various industries varies depending on the type of product, the technical means used and technological schemes. The production of 1 ton of finished products currently consumes the following amount of fresh water: paper 900-1000 m3, steel - 15-20 m3, nitric acid - 80-180 m3, cellulose - 400-500 m3, synthetic fiber 500 m 3, cotton fabric 300-1100 m 3, etc. Huge volumes of water are consumed power plants for cooling power units. Thus, for the operation of a thermal power plant with a capacity of 1 million kW, 1.2-1.6 km 3 of water per year is required, and for the operation of a nuclear power plant of the same capacity - up to 3 km 3 (Rozanov, 1984). Only for energy needs is it taken from water sources of 320 km 3 of water, while 20 km 3 is lost.

Thermal power engineering widely uses circulating water supply systems, using part of the waste and purified water from other industrial production, since relatively low quality water can be used for cooling. Water consumption for energy purposes produces 300 km 3 of thermal runoff, which requires 900 km 3 of free fresh water for dilution.

The share of other industries in total water consumption for industrial needs is even greater - 440 km 3 ; Due to recycling water supply systems, they consume 700 km 3, while simultaneously losing more than 10% of this volume. It is in industrial installations that wastewater is generated that is enriched with particularly toxic compounds that are difficult to remove from waste water. The total volume of wastewater is 290 km 3 . Since modern water treatment technology is still far from perfect and many enterprises in various countries discharge their wastewater into water bodies insufficiently or poorly purified, then as a result, 5800 km 3 of free water is required to dilute this volume of polluted water, i.e. 20 times more.

Water supply for agriculture. The largest water consumer is agriculture. According to rough calculations, in 1990 this sector of the world economy consumed more than 3000 km 3, i.e. 3.5 times more than industry. Almost all of this volume was used for watering irrigated lands and only 55 km 3 for water supply to livestock.

By the beginning of the 1980s, 230 million hectares of land were irrigated in the world. With an average irrigation rate of 12-14 thousand m 3 /ha, from 2500 to 2800 km 3 of clean free water and a significant part (about 600 km 3) of purified and diluted wastewater from the domestic sector and some industrial production were spent on irrigation. According to very rough estimates, approximately 1900 km 3 evaporated from the surface of irrigated lands and was transported by vegetation, 500 km 3 drained into underground horizons. Thus, in contrast to industrial water consumption, the use of water for irrigation sharply increases irrecoverable losses due to unproductive evaporation from the surface of irrigated lands and creates runoff in the form of irrigation or return water, which is difficult to capture, purify and reuse. At the same time, their volume is huge, they are saturated with biostrong (nitrogen, phosphorus) and other easily soluble compounds, due to which the mineralization of water increases. The appearance of significant volumes of mineralized groundwater in subarid or arid landscapes with irrigated lands creates the danger of secondary soil salinization and degradation.

Runoff from livestock farms is a particular problem. Although their total volume in global water consumption for agricultural needs is small (only 10 km 3), they are extremely overloaded with organic compounds, are difficult to restore and cause particularly rapid pollution of water bodies.

According to calculations by M.I. Lvovich (1994), modern water intake from various sources (rivers, lakes, reservoirs, underground horizons) for industrial and domestic needs, irrigation and livestock complexes is more than 4000 km 3, and the volume of waste is approximately 2000 km 3. If we assume that all wastewater is purified according to standards, then in this case at least 8300 km 3 of clean water will be required to dilute it (20% of the total flow and 60% of the sustainable flow). But as a result of imperfections in modern water use and treatment, much more water is polluted. Thus, if quantitative depletion of water reserves from traditional sources on a global scale does not threaten humanity in the near future, a qualitative deterioration is already evident today.

The sharp tension in the water balance and crisis situations in water use increase immeasurably in countries with limited water resource potential, where there are actually no free water reserves for diluting waste and treated water. Such phenomena are typical in many industrialized countries of the world, where underconsumption practically consumes all water resources. This is the situation in foreign European countries and in many areas of the United States. The problem of water supply is even more acute in developing countries, where there is often a shortage of high-quality drinking water, and existing watercourses and surface reservoirs serve as collectors for the discharge of completely untreated industrial wastewater.

Water consumption and its structure are different on individual continents. The features of modern water management depend both on natural factors (primarily the availability of river flow, climatic features, surface structure) and on socio-economic structures. The largest volumes of water are consumed by the economies of Asian countries. Almost 90% of this volume in Asia is spent on agricultural needs. A similar situation is typical for South America and Africa, although in general the participation of these continents in global water consumption is insignificant. IN North America and in Europe, industrial and agricultural water consumption are approximately equal.

Forecasts of future water consumption. There are several options for global forecasts of the use of natural waters by the world economy. One of the options for the world’s water balance at the end of this century was developed by M.I. Lvovich (1986). According to his calculations, the world population, which had increased to 6.2 billion people by 2000 (of which 3.2 billion people will live in cities and use centralized systems water supply) will consume about 480 km 3 of water for municipal and domestic needs, and 320 km 3 of wastewater will appear. If the wastewater is completely treated, then only about 1000 km 3 of water will be required for its subsequent dilution. If modern water consumption practices continue (discharge of untreated or untreated wastewater into water bodies), 6,000 km 3 of water will be polluted.

Energy production in the world, according to the MIREK-HP forecast, will reach 300-330 thousand J by the end of the century. Approximately, about 200 km 3 of water will be withdrawn for energy needs and at the same time 140 km 3 of thermal drains will be formed. Their dilution will require approximately 400 km3 of free water. The remaining industries, taking into account the growth in the volume of their production, by 2000 will need 1800 km 3 of water. Improving closed recycling water supply systems, developing low-water or “dry” technologies, reducing the practice of drainage from industrial enterprises, and improving treatment technology will make it possible, as assumed in this forecast, to limit water intake for industrial purposes to 500 km 3 . The irreversible flow rate will be 120 km 3 , and the waste effluent will be 380 km 3 . 5,700 km 3 will be spent on their dilution. water.

In agriculture, the total area of ​​irrigated land will presumably increase to 320-350 million hectares, and the irrigation rate will be reduced to 9.5 thousand m 3 /ha due to water-saving irrigation methods (sprinkling, drip, etc.). As a result, up to 3000 km3 of water will be withdrawn for irrigation needs, of which 2600 km3 will be spent on evaporation and infiltration. Water consumption in livestock farming will increase to 110 km. Although the volume of wastewater will increase slightly, due to more advanced treatment and disposal, it will pollute much less clean water - about 180 km 3 .

Calculations indicate that the situation will remain tense in the near future. The world economy as a whole at the end of this century will absorb approximately 5.7 thousand km 3 of water (16%) of the total flow), and wastewater in a volume of 1300 km 3 will pollute 8.5 thousand km 3, which is equal to 21% of the total and 61%) sustainable flow.