Message on the topic of protection of natural reservoirs. Blue Planet: what are people doing to protect rivers and other natural objects? Home of many animals

Krasnodar region is a subject Russian Federation since 1937. It is located in the southwest of the country and is part of the Southern Federal District.

Types of reservoirs

In order to move on to the description of the reservoirs of this territorial unit of the Russian Federation, it is necessary to clarify what this concept is.

A reservoir is a temporary or permanent accumulation of water, standing or with reduced flow, in natural or artificial depressions. This term also applies to seas and oceans, but in a broader sense. Oxbow lakes and puddles can be called temporary, that is, those hydraulic objects that arise during certain periods of the year, most often during spring and autumn floods.

Reservoirs of the region

Permanent objects of this type include lakes, ponds, reservoirs and specific reservoirs of the Krasnodar Territory - estuaries. Reservoirs are divided into artificial and natural. The first include reservoirs, dams, ponds and pools.

All of the above hydro objects are available in Kuban, most which occupies the Krasnodar region. In the southwest and northwest, the territory of the region is washed by the waters of the Black and Azov seas, respectively. These are the largest natural reservoirs in the Krasnodar region.

Seas of the Krasnodar Territory

The Black Sea is washed by the border of the region from which serves as the border with Abkhazia to Cape Tuzla. The Kerch Strait connects it with the Sea of Azov, which is 11 times smaller in area than the Black Sea. The Sea of Azov is the smallest sea in Russia. In ancient times it was called the Maeotian swamp.

These reservoirs of the Krasnodar Territory differ sharply from each other. Thus, the greatest depth of the Black Sea is 2210 (2245) meters, while the Sea of Azov is only 14. The water in the first is very salty and below 200 meters is saturated with hydrogen sulfide, while in the second natural reservoir It, desalinated by large rivers - the Kuban and Don, contains little salt. The shores of the Black Sea are covered mainly with pebbles, while the shores of the Azov Sea are covered with shell rock and sand. And if in the Black Sea there are up to 180 species of fish, 40 of which are commercial, then the Azov Sea, until recently, was generally considered the richest in fish reserves in the country.

The largest freshwater lake

In addition to seas, large natural hydrological objects include lakes. Abrau, Kardyvach and Psenodakh are fresh reservoirs of the Krasnodar Territory of this type. The largest freshwater closed lake in the Krasnodar Territory is the Abrau reservoir, located on the peninsula of the same name (Abrausky), 14 km from Novorossiysk. The reservoir is indeed large - its length is 3,100 meters, width - 630. The depth in some places reaches 11 meters.

The area of the mirror is 0.6 square kilometers. Scientists argue about its origin - some consider it karst, others - formed as a result of a landslide. There are suggestions that the lake is a remnant of the ancient Cimmerian freshwater basin. The lake is very clean, as evidenced by the presence large quantity crayfish on the banks. In addition to them, it is also found here. As noted above, the lake is drainless, and only one river flows into it - Durso, as well as numerous mountain streams. And yet, lacking natural drains, the lake becomes shallow. It becomes shallow and silts up, despite the measures taken. Next to it there is a small Dolphin Lake, the depth of which reaches 7 meters. It is adapted for working with marine animals - a dolphinarium has been built here.

The name of the reservoirs of the Krasnodar Territory, each of them, sounds very beautiful and mysterious and is often shrouded in some kind of legend. Lake Abrau and the Durso River flowing into it, combined in the name of the rural district, are associated with a beautiful legend about unhappy love. And the name of the second largest reservoir in the Krasnodar Territory, Lake Kardyvach, is translated from the Abaza language as “in a clearing inside a hollow.”

Lake Kardyvach

All reservoirs of the Krasnodar Territory are beautiful; Kardyvach is often called the lake of dreams. Located 44 km from the now world famous resort of Krasnaya Polyana, located at an altitude of 1838 meters above sea level, this almost regular oval-shaped reservoir is a favorite place for tourists and part of biosphere reserve. The lake is often called mirror - in addition to its beautiful shores, it reflects snow-capped mountain peaks.

The river flowing from it is the longest of all the rivers and streams flowing into the Black Sea. The length of the lake reaches 500 meters, width - 360, depth - 17 meters. It should be added that the lake, located on the southern slope of the Main Caucasus Range, changes color - from emerald green in the spring to bright blue in the summer.

Lake Psenodakh

The third largest lake is the lake of the Lago-Naki plateau - Psenodakh, located at an altitude of more than 1900 meters. The shape of this lake is interesting - it resembles a smile. The reservoir is shallow - no more than a meter (the greatest depth reaches 3 m). The lake is interesting because periodically, and often for unknown reasons, it disappears and then appears again. And when it is there and filled with water, it presents an amazingly beautiful sight - surrounded by meadows and framed by mountain peaks, it is filled with clear and clean water.

Other lakes of the Krasnodar region

Next to Black and Seas of Azov There are salt lakes that were formed as a result of the appearance of an alluvial ridge that separated the reservoirs from the sea. Healing mud found in lakes such as Khanskoye, Golubitskoye and Solenoye, Chemburka and Sudzhukskoye are used in medicinal purposes. The same salty lakes with healing mud are also found in the steppe zones - near Armavir there are two Ubezhensky lakes - Maloe and Bolshoye.

There are lakes such as Staraya Kuban, which was formed from the old bed of the Kuban River. It is interesting because its waters are used to cool the Krasnodar Thermal Power Plant. It is also used for fish farming, and more recently for recreational purposes (swimming and recreational fishing).

Estuaries

Natural reservoirs of the Krasnodar Territory are also a huge array of lagoon and floodplain natural reservoirs, called estuaries. They are located at the mouth of the Kuban River and occupy an area of 1300 square meters. km. Their depth ranges from 0.5 to 2.5 meters. They occurred as a result of processes of formation of a river delta on the site of a sea bay. This happened as a result of the formation of a shell spit, which fenced off the bay from the seas - the Black and Azov. There are many of them - some are listed below, and Kiziltashsky, Yeisk, Beysugsky and Kirpilsky have always been considered the largest. The entire massif of Kuban estuaries is divided into three systems - Taman, Central and Akhtarsko-Grivenskaya. They combine both lagoonal estuaries located near the sea, and floodplain ones - remote from it. There are edges and floodplains on the territory.

Reservoirs

Artificial reservoirs of the Krasnodar Territory are represented by the following reservoirs - Atakaisky and Varnavinsky, Krasnodar and Kryukovsky, Neberdzhaevsky and Shapsugsky.

In the Kuban basin alone in the Krasnodar Territory there are 10 reservoirs. The largest not only in the region, but throughout the entire North Caucasus is the Krasnodar reservoir, which was finally filled with water and put into operation in 1975. It swallowed up the Tshchikskoe reservoir that was previously located here. The purpose of its formation was to combat floods in the lower reaches of the Kuban (such tributaries of the Kuban as Belaya, Pshish, Marta, Apchas, Shunduk, Psekups flow into it) and rice growing.

Protection and use

The use and protection of reservoirs in the Krasnodar Territory is carried out by services of various departments. Thus, reservoirs are used to maintain the required water level for navigation. All reservoirs, except salty ones, are used to irrigate areas with insufficient moisture, to ensure normal watering of fields, including rice fields.

The condition of reservoirs is constantly monitored within the framework of sanitary and epidemiological surveillance and monitoring. The state of water quality is monitored at 297 sampling points. 42 are located on reservoirs of category I (household and drinking supply), 136 - category II (swimming, sports, recreation for the population), 119 - category III (fishery purposes). From May 15 until the end of the summer holiday season, laboratory control of water quality is carried out every ten days. Constant explanatory work is being carried out with the population about the inadmissibility of polluting water bodies.

Bad ecology

The ecological state of reservoirs in the Krasnodar Territory is determined on the basis of information received by control authorities. It can be stated that there are plenty of problems in the region’s water bodies. These include depletion of fish stocks, degradation of water bodies - shallowing, silting, overgrowing of estuaries, waterlogging. Coastal erosion, discharges of prohibited urban waters, contamination of the natural environment with toxic industrial waste, as well as radioactive contamination of the territory and much more have even resulted in precipitation acid rain. The greatest changes in the Krasnodar Territory occurred as a result of water-chemical reclamation, which negatively affected the condition of the soil - due to its oversaturation, up to 50% of chemical fertilizers were washed into water bodies, which could not but lead to disastrous results.

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Freshwater bodies perform several functions. On the one hand, rivers and lakes form an important part of the water cycle in nature.

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On the other hand, it is an important environment for life on the planet with its own unique complex of living organisms.

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Large rivers and lakes are a kind of heat trap, since water has a high heat capacity. On cold days, the temperature near bodies of water is higher, as the water releases stored heat, and on hot days, the air above lakes and rivers is cooler due to the fact that the water accumulates excess heat. In the spring, lakes and rivers become resting places for migratory waterfowl, which migrate further north, into the tundra, to nesting sites.

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Rivers and lakes serve as the only accessible source of fresh water on our planet. Currently, many rivers are blocked by hydroelectric dams, so the water in the rivers plays the role of a source of energy.

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Picturesque banks of rivers and lakes allow people to enjoy the beauty of nature. That is why one of the most important meanings of land-based bodies of water is a source of beauty.

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In the Arkhangelsk region, in addition to the listed functions, rivers play the role of transport routes along which various goods are transported.

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Previously, timber rafting was carried out along the Onega, Northern Dvina and other rivers. With this method, a large number of logs were independently floated downstream during the spring flood. Thus, wood was delivered free of charge from logging areas to large sawmills in Arkhangelsk. This method of floating trees caused irreparable damage to nature. The bottom of the rivers where moth rafting was carried out was heavily clogged with rotting logs. Such rivers became unnavigable in the summer. As a result of wood rotting, there was a low oxygen content in the water.

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Consequences of mole alloy.

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Despite its high economic efficiency, this method of transporting wood caused great harm to the environment. Therefore, it has now been abandoned. Nowadays, wood is transported along rivers in the form of large rafts. In this case, there is no loss of logs, and therefore, rivers and the sea are not polluted.

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Timber rafting along the Northern Dvina.

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Northern rivers are famous for their abundance of diverse fish. They are inhabited by whitefish, char, omul, and herring. In the spring, the valuable commercial fish northern salmon, or salmon, comes to the rivers flowing into the White and Barents Seas to spawn. Currently, the number of this species has greatly decreased due to poaching. To preserve salmon, the state regulates fishing standards for special fishing teams. But sometimes residents catch salmon with nets on their own without permission from fisheries conservation organizations, and in connection with this, the problem of poaching in northern rivers is particularly acute.

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SALMON is an anadromous fish of the salmon family. Length up to 150 cm, weighs up to 39 kg. After feeding in the sea, it migrates to rivers to breed. There are two known races of salmon in the White Sea: autumn and summer. The Northern Dvina salmon run begins in the spring and continues until freeze-up.

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The main negative impact of humans on the condition of rivers and lakes is their pollution by chemical waste. The Northern Dvina is the most polluted. The largest pulp and paper mills in Europe are located on this river. One of them is located near Kotlas, in the city of Koryazhma, and the other two are in Novodvinsk and Arkhangelsk.

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The total pollution of the Northern Dvina is so high that in summer it is not recommended to swim in the river within the city of Arkhangelsk. The problem of water pollution in Arkhangelsk is particularly acute, since in this city the river is the only source of drinking water. To control the quality of fresh water, the state has developed a Water Code. The Law of the Russian Federation “On the Protection of the Natural Environment” has a separate article on the protection of fresh waters. In Russia, maximum permissible concentrations and maximum permissible standards for discharges of harmful substances from industrial enterprises have been developed. The Main Directorate is responsible for the implementation of these laws and for monitoring the quality of wastewater. natural resources and environmental protection.

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Another source of pollution of rivers and lakes is domestic wastewater. Most of the large cities in the Arkhangelsk region are located on the banks of large rivers. Therefore, large amounts of insufficiently treated wastewater can end up in rivers and then into the sea. To maintain high water quality in the rivers of the Arkhangelsk region and preserve the diverse flora and fauna, industrial enterprises must comply with pollutant emission standards, and the population must comply with environmental laws and take care of the wealth that nature has awarded.

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Literature
Ecology of the Arkhangelsk region: Textbook for students in grades 9-11 secondary school/ Under. Ed. Batalova A. E., Morozova L. V. - M.: Publishing house - Moscow State University, 2004. Geography of the Arkhangelsk region ( Physiography) 8th grade. Textbook for students. / Edited by N. M. Byzova – Arkhangelsk, Pomeranian International Publishing House pedagogical university named after M.V. Lomonosov, 1995. Regional component of general education. Biology. - Department of Education and Science of the Administration of the Arkhangelsk Region, 2006. PSU, 2006. JSC IPPC RO, 2006

REPORT ON THE TOPIC: “PROTECTION OF RESERVOIRS”

Plan:

Meaning, role in nature.

Causes of pollution.

Protection of water bodies:

So that you can take action.

What is a pond???

Water - permanent or temporary accumulation of standing or reduced in natural or artificial depressions ( , , etc.). In a broad sense, also the designation And . Science studies water bodies .

By the way, about 71% of the surface covered with water ( , , , , ice) - 361.13 million km. On Earth, approximately 96.5% of water comes from the oceans, 1.7% of the world's reserves are groundwater, another 1.7% are glaciers and ice caps And , a small part is found in rivers, lakes and , and 0.001% in clouds (formed from airborne particles of ice and liquid water) .

There are bodies of water: artificial and natural

Natural bodies of water include: stream, river, lake, sea

Artificial reservoirs include: reservoirs, pond, canal

Meaning, role in nature.

The importance of reservoirs is great. Reservoirs are reservoirs of water, which is necessary for all living things. In addition, the water of reservoirs participates in the water cycle.The role of water in the emergence and maintenance of on Earth, in the chemical structure of living organisms, in the formation And . Water is the most important substance for all living things on the planet . And for those plants and animals that live in reservoirs, this is the only home.

When you approach a body of water in warm weather, you only see some of its inhabitants. It is impossible to see everyone. But there are a lot of them! A body of water is a place where a wide variety of living creatures live.

The role of plants in a reservoir is great. They serve plants and animals and release oxygen into the water, which is necessary for the respiration of organisms. Underwater thickets of plants serve as a refuge for animals.

There are many known animals whose life is connected with water. These are animals, birds, fish, various small animals. Each body of water has its own living conditions. They depend on the size of the reservoir, its depth, water temperature, river flow and many other reasons. But all the animals living in the reservoir have adapted to its conditions.

When plants and animals in a body of water die, their remains fall to the bottom. Here, under the influence of microbes, the dead remains rot and are destroyed. Salts are formed from them. These salts dissolve in water and can then be used to feed new plants.

Natural water pollution - this is a decrease in their biosphere functions and economic significance as a result of the entry of harmful substances into them.

Causes of pollution.

There are natural and anthropogenic pollution. Natural pollution occurs as a result of natural causes - volcanic eruptions, earthquakes, catastrophic floods and fires. Natural (natural) pollution - environmental pollution, the source of which is natural processes and phenomena not directly caused by human activity: volcanic eruptions, dust storms, floods, natural fires, etc.

Anthropogenic (artificial) pollution

- the result of human activity. Currently, the total power of anthropogenic pollution sources in many cases exceeds the power of natural ones.

Artificial (anthropogenic) pollution of water bodies is mainly the result of the discharge of wastewater from industrial enterprises and populated areas into them. Pollution entering a reservoir, depending on its volume and composition, can have different effects on it:

1) change physical properties water (transparency and color changes, smells and tastes appear);

2) floating substances appear on the surface of the reservoir and sediments form (sediment at the bottom);

3) changes chemical composition water (the reaction, the content of organic and inorganic substances changes, harmful substances appear, etc.);

4) the content of dissolved oxygen in water decreases due to its consumption for the oxidation of incoming organic substances;

5) the number and types of bacteria change (pathogenic ones appear) introduced into the reservoir along with wastewater. Polluted water bodies become unsuitable for drinking and sometimes for technical water supply; fish die in them.

In the first decade of the 21st century, anthropogenic pollution of natural waters became global in nature and significantly reduced the available exploitable fresh water resources on Earth.

Humanity consumes huge amounts of fresh water for its needs. Its main consumers are industry and agriculture. The most water-intensive industries are mining, steel, chemicals, petrochemicals, pulp and paper, and food processing. They consume up to 70% of all water spent in industry.

One of the main water pollutants is oil and petroleum products. Oil can enter water as a result of natural seeps in areas where it occurs. But the main sources of pollution are associated with human activity: oil production, transportation, refining and use of oil as fuel and industrial raw materials.

Among industrial products, it has a special place in its negative impact Toxic synthetic substances occupy the aquatic environment and living organisms. They are increasingly used in industry, transport, and household services. The concentration of these compounds in wastewater is usually 5-15 mg/l with a MPC of 0.1 mg/l. These substances can form a layer of foam in reservoirs, which is especially noticeable on rapids, riffles, and sluices. The ability to foam in these substances appears already at a concentration of 1-2 mg/l.

Other pollutants include metals (for example, mercury, lead, zinc, copper, chromium, tin, manganese), radioactive elements, pesticides from agricultural fields, and runoff from livestock farms. Slight danger for aquatic environment metals include mercury, lead and their compounds.

Table 1. Main pollutants of aquatic ecosystems in various industries

Industry

Main types of pollutants

Oil and gas production, oil refining

Petroleum products, synthetic surfactants, phenols, ammonium salts, sulfides

Forestry industry, pulp and paper industry

Sulfates, organic substances, lignins, resins and fatty substances

Mechanical engineering, metalworking, metallurgy

Heavy metals, fluorides, cyanides, ammonium compounds, petroleum products, phenols, resins

Chemical industry

Phenols, petroleum products, synthetic surfactants, aromatic hydrocarbons, inorganic

Mining and coal industry

Flotation reagents, inorganics, phenols

Light, textile and food industries

Synthetic surfactants, petroleum products, organic dyes, other organic substances

A significant amount of dangerous pollutants such as pesticides, ammonium and nitrate nitrogen, phosphorus, potassium, etc. are washed off from agricultural areas. Basically, they end up in water bodies and drains without any treatment, and therefore contain a high concentration of organic substances, nutrients and other pollutants.

The main consumer of fresh water is agriculture: 60-80% of all fresh water is used for its needs. Moreover, its irrevocable consumption is high (especially for irrigation).

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

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

Initially, the number of microscopic algae in such a reservoir sharply increases. With increase food base the number of crustaceans, fish and other aquatic organisms. Then a huge number of organisms die off. It leads to the consumption of all oxygen reserves contained in the water and the accumulation of hydrogen sulfide. The situation in the reservoir changes so much that it becomes unsuitable for the existence of any form of organisms. The reservoir is gradually “dying.”

Pollutants can also penetrate into groundwater: when industrial and agricultural waste seeps from storage facilities, storage ponds, settling tanks, etc. Groundwater pollution is not limited to the territories of industrial enterprises, waste storage facilities, etc., but spreads downstream to distances of up to 20 - 30 km or more from the source of pollution. All this creates real threat for drinking water supply in these areas.

Moreover, groundwater pollution negatively affects ecological condition surface waters, soils and other components of the natural environment. In particular, pollutants contained in groundwater, can be carried out by flow into surface water bodies and pollute them.

Lake Baikal

Almost in the center of the huge continent of Eurasia there is a narrow blue crescent - Lake Baikal. In Baikal mountainous region, surrounded on all sides by high ridges, it stretches over 636 kilometers in length and up to 80 kilometers in width. Baikal's area is equal to Belgium with its almost 10 million population, many cities and industrial centers, highways and railways. 336 permanent rivers and streams flow into Baikal, while half of the volume of water entering the lake comes from the Selenga. The only river that flows out of Baikal is the Angara. In order to understand the enormity of Baikal’s water body, imagine that the Angara, which annually removes 60.9 km3 of water from the lake, would need 387 years of continuous work to drain its bowl. Provided, of course, that during this time not a liter of water gets into it and not a drop evaporates from its surface.

Pollution of Lake Baikal by the waters of the Selenga River

The largest influx Lake Baikal is the Selenga River. The main sources of pollution of the Selenga River are located in Buryatia. There are large industrial cities of Ulan-Ude and Selenginsk. The treatment facilities of the city of Ulan-Ude provide 35% of the total amount of waste discharged into the Selenga.

In 1973, not far from the city of Selenginsk and 60 kilometers from Lake Baikal, the Selenginsky pulp and cardboard mill was opened. Since 1991, a closed water circulation system has been used there.

As the management of the plant assures, the discharge of production waste into the river. Selenga has been completely stopped. But at the same time, the enterprise continues to pollute the air; more than 10,000 cubic meters are emitted per year solid waste, which seep and end up in the waters of the Selenga, and then in Baikal. Chemical substances, used in agriculture, are washed into the Selenga with rains. In addition, the quality of water pollution in Lake Baikal is negatively affected by the discharge of livestock waste and soil erosion. In the deltas of the Selenga River, according to the results of a 2006 study, the concentration of heavy metals such as zinc, lead and copper exceeded the norm by one and a half to two times.

Severe pollution of the river delta. Selenga is the main cause of death of omul eggs.

Consequences of the construction of the Irkutsk hydroelectric power station for Lake Baikal

In 1950, construction began on the Irkutsk hydroelectric power station - the first hydroelectric power station of the Angarsk cascade. The hydroelectric dam increased the water level in Lake Baikal by a meter.

Sudden changes in the water level in Lake Baikal cause enormous harm to the flora and fauna of Lake Baikal. With a rapid decline in the water level of Lake Baikal, the spawning grounds dry out valuable species fish, eggs die. The dam of the Irkutsk hydroelectric power station, which does not have fish passages, blocks the migration routes of fish that go to spawn in the upper reaches of the Angara. Valuable breeds of sturgeon and whitefish are being replaced by sorog, perch, and ruff. Buryat scientists came to the conclusion: a sharp change in water level affects the entire Baikal ecosystem, leading to mixing of water masses and severe destruction of the banks. Spawning sites and fish reproduction are in danger.

Water pollution from waste from coastal settlements

More than 80 thousand people live in small towns and villages in the coastal zone of Lake Baikal.

Together, all these settlements They dump about 15 million cubic meters of waste per year. Treatment facilities for domestic and industrial wastewater in settlements near Lake Baikal are either completely absent or of very low quality.

“The laws” of ecology by B. Kammoner are very clear and concise: 1) everything is connected to everything; 2) everything has to go somewhere; 3) nature “knows” better; 4) nothing is given for free.

Causes of pollution of Lake Issyk-Kul.

What measures are already being taken.

What I would like to do.

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Functions of fresh water bodies

Freshwater bodies perform several functions. On the one hand, rivers and lakes form an important part of the water cycle in nature.

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On the other hand, it is an important environment for life on the planet with its own unique complex of living organisms.

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Fresh water sources

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Nature of reservoirs

Picturesque banks of rivers and lakes allow people to enjoy the beauty of nature. That is why one of the most important meanings of land-based bodies of water is a source of beauty.

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Transport function of rivers

In the Arkhangelsk region, in addition to the listed functions, rivers play the role of transport routes along which various goods are transported.

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Consequences of mole alloy

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Wood transportation

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Timber rafting along the Northern Dvina

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River fish

Northern rivers are famous for their abundance of diverse fish. They are inhabited by whitefish, char, omul, and herring. In the spring, the valuable commercial fish northern salmon, or salmon, comes to the rivers flowing into the White and Barents Seas to spawn. Currently, the number of this species has greatly decreased due to poaching. To preserve salmon, the state regulates fishing standards for special fishing teams. But sometimes residents catch salmon with nets on their own without permission from fisheries conservation organizations; in this regard, the problem of poaching in the northern rivers is especially acute.

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Salmon

Salmon is an anadromous fish of the salmon family. Length up to 150 cm, weighs up to 39 kg.
After feeding in the sea, it migrates to rivers to breed. There are two known races of salmon in the White Sea: autumn and summer. The Northern Dvina salmon run begins in the spring and continues until freeze-up.

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Human influence on water bodies

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Sources of environmental danger

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Pollution of the Northern Dvina

The total pollution of the Northern Dvina is so high that in summer it is not recommended to swim in the river within the city of Arkhangelsk. The problem of water pollution in Arkhangelsk is particularly acute, since in this city the river is the only source of drinking water. To control the quality of fresh water, the state has developed a Water Code. The Law of the Russian Federation “On the Protection of the Natural Environment” has a separate article on the protection of fresh waters. In Russia, maximum permissible concentrations and maximum permissible standards for discharges of harmful substances from industrial enterprises have been developed. The General Directorate of Natural Resources and Environmental Protection is responsible for the implementation of these laws and for monitoring the quality of wastewater.

Ecology of the Arkhangelsk region: Textbook for students of grades 9-11 of secondary schools / Ed. Ed. Batalova A. E., Morozova L. V. - M.: Publishing house - Moscow State University, 2004.

Geography of the Arkhangelsk region (physical geography) 8th grade. Textbook for students. / Edited by Byzova N.M. - Arkhangelsk, publishing house of the Pomeranian International Pedagogical University named after M.V. Lomonosov, 1995.

Regional component of general education. Biology. - Department of Education and Science of the Administration of the Arkhangelsk Region, 2006. PSU, 2006. JSC IPPC RO, 2006

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Our reservoirs and their protection (E. S. Liperovskaya)

Water protection and school

The importance of reservoirs in the national economy. School curricula pay little attention to such an important object National economy like bodies of water.

Meanwhile, the water resources of our country are enormous. In the Soviet Union there are more than 250 thousand lakes with an area of over 20 million hectares and 200 thousand rivers. The total length of our medium-sized rivers is 3 million kilometers. The annual flow of rivers in the USSR reaches 4000 billion cubic meters. Hundreds of thousands of kilometers of rivers are used for water transport. Since ancient times, rivers have been the main routes of communication, trade and cultural connections between peoples, and cities arose along their banks.

The USSR ranks first in the world in terms of hydraulic energy reserves. Hydroelectric power stations with a capacity of about 300 million kilowatts can be built on large and medium-sized rivers of the USSR. Even on small rivers there is an energy reserve of 20-30 million kilowatts, which ensures the construction of collective farm power plants.

The construction of dams, locks, hydroelectric power stations contributes to integrated use rivers: navigation conditions are improved, field irrigation is improved, river flow is regulated, and settlements are provided with water. The construction of large dams and hydroelectric power stations is transforming the entire region. Construction of the canal named after. Moscow allowed part of the Volga waters to turn towards Moscow and created a shipping route, turning Moscow into a major river port of three seas: the Caspian, White and Baltic. The construction of a powerful hydroelectric power station named after Lenin in the area of the city of Kuibyshev and the Volgograd hydroelectric power station, producing about 10 billion kilowatts per year each, will supply energy to Moscow, Donbass, the Urals, Kuibyshev, electrify railways, ensure land irrigation and shipping.

Reservoirs are sources of water supply, fishing, hunting, and useful aquatic animals and plants.

Rivers and lakes are also places of recreation and tourism.

Participation of schoolchildren in the protection of water bodies. We must be well aware of, protect and increase our water resources.

Article 12 of the Law on Nature Protection of the RSFSR, dedicated to the protection of water bodies, poses tasks of enormous importance to every Soviet citizen.

Promoting the protection of natural waters among schoolchildren is of great importance. Already in the elementary grades, the teacher must instill in students an attentive and careful attitude towards water sources, teach them to keep wells and other water supply sources clean, not pollute the water with garbage when boating, and explain the importance of water sources for health and the national economy.

In secondary schools, the topic of water protection can be the subject of special excursions, during which the teacher must show the relationship of reservoirs with the surrounding landscape and the dependence of aquatic animals and plants on the state of pollution of reservoirs.

In high school, students can not only get acquainted with the life of reservoirs, but also actively contribute to their protection. Regular observations of the regime of local reservoirs by schoolchildren can bring considerable benefit.

The Main Directorate of the Hydrometeorological Service under the Council of Ministers of the USSR is responsible for recording all water resources, including rivers. Monitoring of rivers and their regime is carried out at special hydrometeorological posts and hydrometeorological stations. The number of such stations was 5510 in 1957 and has now increased greatly. At these stations, water levels, flow rates, temperature, ice phenomena, sediment, water chemistry and other data are recorded daily. All this information is summarized and published in a periodical publication of the Hydrometeorological Publishing House, called the “Hydrological Yearbook”. The data obtained is used for planning the national economy. Along with this, the study of rivers by local organizations, including school organizations, can be very important, and all observations obtained in this way should be reported to hydrometeorological service organizations - preferably to the nearest water-measuring station.

To successfully familiarize students with the life of our reservoirs and participate in their protection, the teacher must himself acquire basic information about this area.

Nature and life of reservoirs

River flow. Movement of water in the river. The movement of water in rivers has a number of features and is characterized by complex phenomena specific only to rivers.

River flow is formed from atmospheric precipitation flowing into the river along the surface (surface runoff) and seeping through the soil (underground runoff). Unevenness of precipitation and snow melting both within one year and in different years causes continuous changes in flow rates and water levels in rivers. In accordance with this, rivers experience periods of prolonged low levels, the so-called low water, when the river is fed mainly by groundwater, and seasonal long-term rises in levels (usually with the release of water onto the floodplain), caused by snowmelt, called floods. In contrast to floods, irregular, relatively short-term significant rises in water levels can also occur in the river - floods resulting from heavy downpours or heavy rains. Floods can occur at any time of the year, depending on local geographic and climatic conditions. They reach particular strength when destroying forests in the river basin, regulating spring snowmelt and weakening erosion from the soil surface. That is why the protection and proper exploitation of forests is one of the most important tasks in regulating river flow.

The main force determining forward movement water in rivers is the force of gravity due to the slope of the river from source to mouth. In addition to gravity, the mass of water in the river is affected by inertial forces called Coriolis forces, which arise as a result of the rotation of the Earth, since points on the surface of the globe located closer to the poles move in a circle more slowly than those lying near the equator. The mass of water in a stream flowing in the northern hemisphere from north to south will move from lower to higher speeds, that is, it will receive acceleration. Since the Earth's rotation occurs from west to east, acceleration will be directed to the east, and inertial forces in the opposite direction - to the west and will press the flow towards the western (right) bank. When the flow moves from south to north, it will receive negative acceleration directed against the direction of the Earth's rotation - from east to west. In this case, inertial forces will press the river to the eastern, i.e., also right, bank. Also, the stream flowing along the parallel will be pressed against the right bank. Thus, it turns out that Coriolis forces in the northern hemisphere always push the flow to the right bank, regardless of the direction of the river flow, and in the southern hemisphere - vice versa. Coriolis acceleration, acting on a moving mass of water, causes the appearance of a transverse slope of the water surface of the flow.

The centrifugal force acting during the river flow at turns, similar to the Coriolis force, also creates a transverse slope in the river. As a result, water begins to move in the plane of the living section of the river. In this case, near the concave shore, water particles move from top to bottom, then along the bottom to the convex shore and further, near the surface, from the convex shore to the concave one. These internal currents are called transverse circulations. The movement of water in the river in the longitudinal direction combines with transverse circulations, and as a result, the paths of movement of individual water particles take the form of spirals elongated along the riverbed (Fig. 1).

River bed formation. Despite the fact that the transverse velocities of water movement are many times lower than the longitudinal velocity of the flow, they have a serious impact on the internal structure of the flow and on the deformation of river channels. Since soils are usually heterogeneous, in the place where they are most susceptible to erosion, the shore will begin to collapse. The river will take on a characteristic meandering shape. The bends of river channels, formed in the process of erosion and deposition by the flow of soil particles, are called meanders (meo in Latin - flow, move).

In the process of their gradual development, the branches of the meander can become so close to each other at the base that at high water levels (during floods and floods), the remaining isthmus will break through (Fig. 2), the channel will straighten in this area and the flow will be directed along a shorter path. The flow velocities in the bend that remains to the side will drop sharply, and sediment deposition will begin at the beginning and end of it. These sediments can eventually completely separate the bend from the main channel. An isolated section of the old channel is formed - an oxbow lake. A flow moving along a straightened section with a greater slope will increase its speed, the process of meandering the channel will continue, and the formation of new bends will begin.

As a result of intense water circulation at bends, the concave banks are washed away and deep-water sections of the channel-reaches are formed near them, and near the convex banks the flow slows down and shallow sections - shoals - are created. Gradually growing downstream, they can lead to the formation of shoals and spits near the convex bank. Since the reaches are formed alternately at the right and left banks, the transverse circulation of one direction is transformed into circulation of the opposite direction. This leads to the fact that the transverse circulations at the point of transition from one reach to another are weakened and break up into two (or more) independent equally directed circulations. Sediment begins to settle across the entire width of the river and forms shallow areas - riffles that cross the river from bank to bank and completely or partially connect two adjacent shallows. The river seems to slide down the river valley and gradually recycles all the soils that make up the floodplain.

Floodplains can be of different widths. On the Oka River near Kashira the width of the floodplain is 1 km, near Ryazan - 15 km, and on the Volga between Volgograd and Astrakhan there is the Volga-Akhtuba floodplain, the width of which ranges from 30 to 60 km.

Flood meadows are very fertile, as they are fertilized every year with river silt. In small floodplains that mostly dry up in summer, a lot of aquatic animals breed, which are washed into the river during floods.

Lake formation. A lake is a natural body of water, which is a large mass of water inside a closed pit, constantly at rest or slowly flowing. The formation of lake depressions (otherwise called beds or pits) in the Moscow region depends on the following main reasons:

1) damming of the river with accumulated sediment; 2) the formation of failures in place of dissolving calcareous rocks; 3) excavation of soil from quarries; 4) glacier activity.

Most lakes in the Moscow region are of glacial origin. As the glacier moved, it created a channel, rolling stones, sometimes of considerable size. Glacial lakes can be recognized by the presence of ridges of huge smooth boulders along the shores and at the bottom of the lake.

Over time, the lake changes, causing significant impacts on its shores. As a result of the processes of erosion and sedimentation, the following series of zones are formed in the lake in the direction from the shore to depth (Fig. 3):

1) surf zone (already) - at the water’s edge;

2) coastal shallows (zhz);

3) underwater slope (sg);

4) deep-water zone - in the middle of the lake (gd).

Lake inhabitants. The bottom and water column of the lake are inhabited by animals and plants; Among them, two main groups are distinguished depending on their habitat: bottom - benthos and organisms of the water column - plankton. The benthos (animals and plants) spend their entire lives at the bottom of the lake. Planktonic organisms float or seem to float in water without sinking to the bottom (A. N. Lipin, 1950).

Plants in the reservoir are distributed in the so-called littoral zone, which is located along the coastal shallows and partially extends onto the underwater slope. Littoral is limited by penetration range sunlight under water. As can be seen in Figure 4, plants grow closer to the shore, rooting at the bottom, whose hard leaves rise above the water: reeds, reeds, lake horsetail, cattails.

Further, in the direction from the shore to the middle of the reservoir, there are plants with floating leaves: water lilies, egg capsules, duckweed, and even further submerged plants - pondweed, villain, hornwort, which are completely under water and expose only flowers to the air.

The smallest lower plants, such as blue-green algae, green algae and diatoms, form plant plankton, which during periods of their strong reproduction causes the so-called bloom of the reservoir. During flowering, all the water appears green.

Chemistry of water. Fresh water contains small amounts of salts - from 0.01 to 0.2 g per liter, in contrast to sea water, where the salt concentration reaches 35 g per liter.

Fresh waters are dominated by calcium salts, which form the skeletons of fish and the shells of some invertebrates. Iron salts are also present in water. Iron deposits can be seen as rusty spots along the banks of rivers or lakes where springs come to the surface. If there is a high iron content in drinking water, an unpleasant rusty taste occurs and a brown precipitate forms.

For aquatic organisms, gases dissolved in water - oxygen and carbon dioxide - are of great importance. Oxygen comes from the air and is released by aquatic plants; it is consumed during the respiration processes of organisms. Carbon dioxide is produced by respiration and fermentation and is consumed by plants to assimilate carbon. As the temperature rises, the amount of gases dissolved in water decreases. By boiling water, you can free it from all dissolved gases, including oxygen, and therefore fish dropped into boiled cooled water instantly dies from suffocation.

Reservoirs are sources of water for drinking and technical water supply systems. At the point where water is collected for the water pipeline, a security zone is established, within which the release of sewage, swimming, livestock watering, and any pollution of the banks is prohibited. The water intake site should be located along the river above the city, away from large factories, bathhouses, sewers, and also, if possible, away from tributaries that can introduce pollution from the upper reaches. The degree of purity is controlled by water tests. At the site where water is taken from the reservoir, pumps are installed to pump water. Water is taken from a depth of at least 2.5 m, passes through large gratings to retain plant residues and large suspended matter, and then flows through pipes for purification. Aluminum sulfate is usually added to precipitate turbidity. After partial separation from turbidity in settling tanks, the water enters the filters. Slowly passing through sand layer, it is freed from suspended particles and algae. Purified water is disinfected by chlorination and supplied to a clean water reservoir, and from there it is pumped into the water supply network.

Fishes of our waters. Numerous lakes and rivers of the USSR are rich in valuable rocks commercial fish. IN large rivers There are, for example, sturgeon, stellate sturgeon, beluga, sterlet, pike perch, carp, and bream. However big fish It is caught only with special gear, and amateur fishermen, including schoolchildren, usually catch smaller fish: roach, bleak, rudd, dace, asp, perch, pike, ruffe, crucian carp, burbot, tench.

In order to protect fish stocks in reservoirs and catch fish correctly, you need to know how fish live. Unfortunately, there are still frequent cases of predatory fishing - poaching. Often children also fish using illegal methods. Therefore, in those schools where there are many amateur fishermen among the students, the teacher must either explain to them the rules of fishing himself, or invite a knowledgeable fisherman to do this.

Schoolchildren need to be educated in the spirit of fighting poaching. Catching juveniles of valuable fish species causes great damage to fisheries; Likewise, predatory fishing by poachers during spawning undermines the fishery. Therefore, the law prohibits fishing with a small-mesh net, fishing with a spear, and fishing for large fish during spawning periods.

A teacher in the Moscow region should have an idea of the main types of local fish (Fig. 5, 6, 7); it can be compiled from the literature (Cherfas B.I., 1956, Eleonsky A.N., 1946).

Fish are bottom-dwelling (for example, bream, crucian carp, tench, burbot) and pelagic, that is, living in the water column (pike perch, pike, roach, dace). There are also peaceful and predatory fish. Predatory fish are those that feed on other fish, while peaceful fish eat algae and invertebrate animals such as mollusks, worms, and insect larvae.

Bream It has a strongly laterally compressed body, its head and mouth are small, and there is a characteristic narrow keel in front of the dorsal fin. It is found both in lakes and rivers, lives in reservoirs near the bottom, and sometimes reaches a length of 45 cm.

crucian carp usually lives near the bottom in low-flow ponds. This fish is sluggish, inactive, but extremely hardy. Crucian carp are easily distinguished by the golden hue of their scales and the jagged ray of their dorsal fin.

Asp distinguished by a long lower lip, which is curved like a bird's beak; There is a notch in the upper lip where this beak fits. The fins are gray or slightly reddish. The fish is strong and lives in fast currents. It feeds on dace, gudgeon, and bleak.

Som- a voracious predator, eats not only live prey, but also carrion. Caught on pieces of meat and frogs. Usually it lies in holes under snags, only in hot weather it swims out to the middle of the pool. Slow sedentary fish. Reaches a weight of 20 kg.

Zander also a predator (Fig. 6). Its scales are grayish on its back, its sides are golden with dark stripes. The dorsal fin is in the form of a spiny fan. It is found in rivers and lakes in deep places and holes, on clean sandy or rocky soil. Spawns in mid-May. It is caught only at dawn using small live fish: bleak, gudgeon, ruff.

Pike characterized by spotted sides, while the back is black and the belly is white (Fig. 7). The fins are orange. The elongated head ends with a flattened, duck-like nose. The mouth is full of many very sharp teeth of different sizes - from the smallest to large fangs with hard enamel. The teeth are curved inwards towards the throat. Each of the teeth is movable, as if on a hinge, but does not fall out. Pike - large predator. Pike can be found everywhere, but it prefers calm water near grass and snags, where it hides, lying in wait for prey. It is caught with live bait, even with small squints.

Rudd distinguished by red fins. The eyes are red-yellow. Lives in thickets of plants.

Tench has rounded fins and a small mouth directed upward. The body is dark, always thickly covered with mucus, the eyes are red. Lives in lakes, bays and oxbow lakes on muddy bottoms. The fish is calm and lethargic, but strong and tenacious (Fig. 5).

At the burbot very small scales are covered on the outside with a thick layer of mucus. The body is dark with light spots, the eyes are also dark, it lives in rivers at the bottom under driftwood. It feeds on fish and caviar, of which it eats a lot. Hunts at night. Caught on pieces of fish or frogs. The fish is strong.

Ruff - small fish, up to 15 cm in length. It has one dorsal fin, the front part of which is spiny and the back part is soft. There is a spine on the ventral fin. In spring it eats fish eggs. Caught with an earthworm.

Perch has two dorsal fins and small scales. The body is green-yellow with black stripes on the sides. Eats caviar and small fish.

Pike and pike perch feed on young fish. Pike, eating up to 30 kg of small fish from other fish, increases in weight by only 1 kg. Pike perch makes better use of food: it gives a gain of 1 kg in exchange for 15 kg of small items eaten. Pike perch is advantageous in that it does not stay in the coastal strip, but on the stretch and feeds on low-value fish species (verkhovka).

In relation to harmful, i.e. predatory, fish, measures must be taken to reduce their numbers by catching them during the spawning period. But also for peaceful fish control is needed, since overpopulation of a reservoir with them can lead to their grinding due to lack of food.

Fish ponds. Many fish ponds have been built in the USSR, but many collective farm ponds and peat quarries can also be equipped for fish farming and stocked with fish, thereby increasing the country’s fish output.

About 250 thousand quintals of fish are currently produced in ponds alone; however, this does not reach even 1% of all fish production in the USSR. And by the end of the seven-year plan, in 1965, it is planned to increase the yield of pond fish to 2.6 million centners (Gribanov L.V., Gordon L.M., 1961).

A common form of fish ponds is carp farming (Eleonsky A.N., 1946). For carp spawning, standing or low-flowing, shallow, well-warmed by the sun reservoirs located on fertile soil with aquatic vegetation are suitable. Carp spawning occurs at the end of May, when the water warms up to 18-20°. The eggs attach to aquatic plants, and after 4-6 days tiny fry emerge from them and soon begin to feed on small aquatic animals. As they grow up, they switch to feeding on worms and larvae. The favorite food of adult carp is red bloodworm. Carp is characterized by rapid growth: in the spring it weighs 20-30 g, and by autumn it reaches 500-700 g.

Carp ponds have an average productivity of 2 quintals of fish per 1 hectare, in other words, 300 pieces weighing up to 600 g. A pond can produce such products due to the use of fish for feeding living aquatic organisms. But thanks to the use of measures to intensify the economy - fertilizing ponds, fertilizing with grain, vitamins, microelements, combined compacted planting (carp along with silver carp, crucian carp and tench) - it is possible to increase the productivity of ponds by five, ten or more times. For example, on the collective farm in the village of Dedinova, Podolsk district, Moscow region, they raised about 9 centners of fish and received an income of 5.7 thousand rubles per 1 hectare of pond (Gribanov L.V., Gordon L.M., 1961). And at the fish farm "Para" in Sarajevo district Ryazan region in ponds with an area of 140 hectares they even grew 19.1 centners of fish per 1 hectare of pond (Pravda dated July 4, 1962).

Water pollution and water purification. Enormous harm to fishing, water supply and the use of reservoirs for any other economic purposes is caused by pollution caused by waste effluents from factories and enterprises. A number of our rivers (this especially applies to small rivers) are extremely polluted. In many places, fish have ceased to be found, livestock watering places are dangerous, swimming is prohibited, and pollution threatens to reach such proportions that even after the cessation of wastewater discharge, such reservoirs will be unsuitable for national economic purposes for a long time. Pollution of water bodies is continuously increasing. The variety of wastewater is increasing. If in pre-revolutionary Russia the main pollutants were household, textile and leather waste, now, in connection with the development of industry, oil, artificial fiber, detergent, metallurgy, and paper and cellulose waste have become important. Industrial wastewater may contain toxic substances: compounds of arsenic, copper, lead and other heavy metals, as well as organic substances: formaldehyde, phenol, petroleum products, etc.

The reservoir has the ability to self-purify. Organic contaminants entering water are subject to bacterial decay. The bacteria are consumed by ciliates, worms and insect larvae, which in turn are eaten by fish, and organic pollution disappears from the reservoir. It is much more difficult to get rid of toxic substances: some substances, when absorbed by fish, make the fish meat taste unpleasant or even harmful to eat. Therefore, the sanitary inspection provides for standards for the release of toxic substances into bodies of water, above which descent is prohibited, and monitors their implementation.

Wastewater containing a lot of organic pollutants is treated biochemically. Depending on the nature of the contaminants, wastewater treatment proceeds in two ways: 1) oxidation of pollutants with air oxygen or 2) oxygen-free fermentation with the release of methane formed from the carbon of organic compounds.

Among the oxidative cleaning methods, the oldest is cleaning in irrigation fields. The disadvantage of this method is that the field area is too large. Soviet scientists have developed more intensive cleaning methods in structures that occupy a smaller area: aeration tanks or biofilters, where cleaning is carried out using activated sludge when blown with air. Activated sludge is similar to sludge from the bottom of reservoirs: the same microorganisms (ciliates, rotifers and flagellates) that can usually be found at the bottom of a reservoir develop in it, but, thanks to the abundant continuous influx of organic matter with the waste liquid, which serves as food for microorganisms, and good condition aeration, an excessively large number of bacteria and protozoa develop in the aeration tank. They intensively consume organic matter and thereby purify waste liquid. After being in the aeration tanks, the water settles to separate from the silt and, already purified in this way, is discharged into the reservoir.

Excursions to reservoirs

Purposes of excursions. Students can be introduced to bodies of water on one-day school excursions, in summer camps, during agricultural practice, and on hiking trips. To explore different types of reservoirs (lake, reservoir, pond, river), you need to conduct at least 3-4 excursions. It is also advisable to visit a fish farm, waterworks and wastewater treatment plant.

The goals of excursions with students to bodies of water are as follows:

1. Show the importance of reservoirs in the life of the region - the benefits they bring and the beauty they add to the native nature.

2. Instill in schoolchildren a love for water bodies, the habit of treating them with care and striving to increase their natural wealth.

3. In the process of observing aquatic animals and plants, develop students’ powers of observation, the ability to analyze nature and establish the patterns of life of organisms in communities.

4. Show how communities of animals and plants are closely related to the surrounding habitat conditions and landscape.

5. Involve students in the proper use of this reservoir.

Preparing for excursions. Equipment. When organizing an excursion to a reservoir, the teacher must first familiarize himself with it and find out what the surrounding landscape is like, especially vegetation and soil, the nature of the banks, and, if possible, determine the origin of the reservoir. He must find out from the local population the prevailing depths, dangerous places and holes, muddy banks, the nature of the bottom soil, find out the possibility of traveling by boat.

From a conversation with fishermen, the teacher finds out what types of fish are found in the reservoir, what were found before, what are the reasons for their disappearance; where industrial wastewater or domestic wastewater is located along the banks.

It is advisable to collect some of the most common species from plants and animals and identify them yourself using keys or find out their names from specialists.

Before going on an excursion, the teacher conducts a conversation in which he explains its purpose - getting to know bodies of water, their life and significance for humans.

The teacher explains how each excursion participant should keep a diary. The recording must be accurate and is always done immediately, on the spot, under the fresh impression of the observed phenomenon. The initiative of students in searching for new original forms of recordings should be welcomed.

In advance, together with the students, the teacher prepares equipment for the excursion (Fig. 8, 9, 10).

To take a plan of the lake you need: tape measure, milestones. You should stock up on special sticks as milestones instead of breaking trees; you also need a homemade compass. To make a compass, you need to take a ruler, draw a straight line on it and attach a compass in the middle so that the north-south arrow of the compass coincides with it. At the ends of the line, two pins should be inserted strictly vertically. The resulting compass needs to be mounted on a tripod.

To measure depths you need a lot. To do this, the rope is marked with colored ribbons at meters and half meters, and a weight or stone is tied to the end. The lower surface of the load is rubbed with lard so that pieces of soil stick when the load falls to the bottom.

It is better to take a thermometer with divisions in tenths of a degree or at least half a degree. The end of the thermometer is tied with hemp from a rope, like a tassel. Then, when quickly raised from a depth, the thermometer retains the temperature of the water in which it was immersed for several minutes while it is counting degrees.

A Secchi disk is used to measure water transparency. A metal round plate the size of a plate is painted with white oil paint and tied horizontally in the center with a rope. When immersing a disk, the depth at which it is not visible is taken into account.

The plankton mesh is made from silk mill gas, which is distinguished by its strength and uniform size of holes (cells); The gas number corresponds to the number of cells per 10 mm of fabric. To collect daphnia, you can use gas No. 34, and for small plankton - No. 70. The mesh consists of a metal ring with a diameter of 25 cm, bent from thick copper wire, and a fabric cone. A funnel (like a kerosene) made of stainless material with a clamp or tap at the end is attached to the end of the cone. The mesh pattern is made from a square piece of fabric (Fig. 8). Before sewing both halves of the cone, you need to use the same pattern to make arc strips (a) from calico or canvas and sew them onto the gasket.

A dredge for collecting benthos consists of a metal frame to which a bag made of rare burlap and a rope are attached. The frame is made from an iron strip 2 mm thick, 30 mm wide and 1 m long, bent into a triangle and fastened at one end.

The net is made from a metal hoop with a diameter of 20-30 cm. The hoop is attached to a stick. The net bag is made of burlap or mill gas, rounded towards the end (for its pattern, see the first article).

The scraper is used to collect fouling and organisms living in plant thickets. It is a type of net, but has a flat steel strip 2-3 cm wide. To attach the bag, holes are made on one side of the steel strip. The bag is made of coarse mill gas. To collect organisms, you need to have several jars with stoppers and alcohol or formaldehyde.

Excursion to the well. You can start the cycle of excursions by getting acquainted with the nearest well, from which they take drinking water. A well is different from artesian well shallower depth of the aquifer. In this regard, contamination from the soil can penetrate into the well, and when constructing wells, they are located away from garbage cesspools, cemeteries and sewage drains.

By examining the well, you can become familiar with the influx of groundwater. To do this, you need to measure the depth of the well using a rope with a heavy metal glass at the end, attached to it with the bottom up. When you hit the water in the well, a loud sound is made. In the morning and evening, the water levels in the well are different due to water consumption and groundwater inflow. A bottle of water is taken from the well for chemical analysis in the school office.

Excursion to the river. When going on an excursion to the river, you need to familiarize yourself with a map of the river and its basin. If this river is small, with high school students you can measure the speed of the flow and its flow.

Current speed is measured with floats. Two alignments are selected - upper and lower. The distance between the gates is taken such that the duration of the float's travel along the river core between them is at least 25 seconds. Above the upper target at a distance of 5-10 m, another launch target is selected. It is done so that the float thrown in this alignment, when approaching the upper alignment, takes on the speed of the flow jets. After setting out the alignments, the living cross-sectional areas on two alignments are measured. The measurement of live sections is carried out by measuring the depths with a rod or pole with divisions at equal intervals, usually at 1/50 or 1/20 of the width of the river, along the towline, which is pulled at each section from bank to bank. The living cross-sectional area can be calculated using the formula: W = (n 1 + n 2 + n 3 ... n n ⋅ b, where n are the measured depths, b are the intervals between measurements in meters. Wooden circles are used as floats, sawed off from a log with a diameter of 10-25 cm and having a height of 2-5 cm. For better visibility, the floats are painted with bright paint or equipped with flags. It is advisable that the float protrudes as little as possible above the surface of the water to avoid the effects of wind.

On rivers up to 20 m wide with a more or less fast current, at the launch point, 10-15 floats are sequentially thrown into the pitch area. The moments of passage of each float through the upstream and downstream alignments are noted with a stopwatch, and the duration of the float's travel T between the alignments is calculated.

The float speed Vpop is found using the formula

V pop	L	,

	T

where L is the distance between the targets, T is the time it takes for the float to pass in seconds. Of all the floats, select the two with the highest speeds and derive Vmax from them. pov - average maximum surface speed of water in the river. Then calculate the average flow speed of the entire river V av = 0.6 V max. pov and the average living section area W for two sections - upstream and downstream. River flow Q is determined by the formula

Q = V avg × W.

For example, let us point out that the flow of the Moscow River at Pavshin is on average about 50 m 3 per second.

On the river, the temperature and transparency of water are measured in deep places, near the shore, near springs and tributaries. The differences indicate the presence of current jets.

It is useful to have students talk to local fishermen. It is advisable to attend net fishing conducted by the local population and see representatives of the local ichthyofauna.

When observing small river organisms, you should pay attention to adaptations to life in fast-flowing water. Thus, mayfly larvae, which can be found under stones, have a flattened shape that protects them from being moved by the current. Mayfly larvae differ from similar stonefly larvae by three tail filaments.

The adaptations of caddisfly larvae consist of the formation of strong houses from the surrounding material (grains of sand, leaves, sticks), due to which the animal is protected from damage when rolling along the bottom. In addition, caddisfly larvae have strong hooks with which they can cling to plants or other hard substrate. There are predators among caddisfly larvae, so it is dangerous to place them in the same aquarium with fish fry.

Along the banks of rivers you can find large bivalve mollusks (toothless and pearl barley) crawling along the bottom in places with silt rich in organic matter. They partially bury themselves in the mud, exposing their respiratory siphons into the water above the mud to draw clean water to their gills.

Excursions to a lake or pond. There are several excursions available to the lake:

1) for shooting a plan; 2) for measuring depth; 3) to get acquainted with plants and animals. An excursion to the lake can be replaced by a visit to a quiet backwater of the river, which is approaching it according to its regime.

The first excursion to the lake is carried out along the shores.

If the lake or pond is small, then it is quite possible to film its plan with high school students. It is recommended that you familiarize yourself with the methodology for this case according to Lipin’s book and use the method that uses a compass. Two people work with the compass, the rest set up milestones and measure distances. Coastal places are plotted on the plan: villages, arable lands, vegetable gardens, forests, streams flowing into a reservoir. At home, students draw a plan to a certain scale. The task is given to calculate the area of the lake.

The next excursion to the lake is by boat. This excursion, like the previous one, should be carried out with older schoolchildren. Having chosen a stable flat-bottomed boat, they sail across the lake in a straight line. If we measure the depth at several points along the course of the boat, we will obtain data for compiling a longitudinal profile of the lake.

During the next trip, temperature and water clarity are measured and living material is collected. To work on collecting material, five students are needed, a minimum of three students and a teacher: a rower, a helmsman, a planktonist, a collector of plants and benthic organisms, and one person for all records. Under no circumstances should the boat be overloaded with extra people.

The work is distributed as follows: the rower rows and at certain intervals, at the command of the leader, stops the boat. It is good to have an anchor that holds the boat in place during work. The helmsman gives the direction of the boat, he can also make entries in the diary and write labels. When the boat stops, one person measures the temperature (first of the air in the shade, then of the water), depth, and transparency.

The planktonist lowers the plankton net into the water while the boat is moving slowly and, holding it barely under the surface of the water for 5-7 minutes, pulls it behind the boat. After this, he takes out the mesh, concentrates the contents in the lower funnel of the mesh, washes it into a bottle and fixes it with alcohol right there on the boat, adding 1 part alcohol to 2 parts water. It can also be fixed with formalin (5 cm 3 per 100 cm 3 of water) or even with a solution of table salt (about 1 teaspoon per 100 cm 3 of water). Organisms are well preserved in formaldehyde, but you need to work with it with caution and under no circumstances give it undiluted to children, as it is very caustic; This fixative can be used when working only with those students who can be relied upon.

One of the participants on the boat trip must be busy collecting plants, as some plants cannot be obtained from the shore. When collecting plants, the teacher draws students' attention to the arrangement of plants in zones.

Plants on the boat can be collected in damp pieces of gauze, labeled with pencil on parchment paper, and placed in a herbarium folder upon return to shore.

In order to beautifully arrange small filamentous algae on paper, you must first immerse them together with the paper in water and then carefully remove them; then the individual threads will lie evenly on the sheet, after which you can dry them.

While going around on a boat, the teacher draws attention to the flowering of the reservoir. If the bloom is intense and gives the water a thick color, you can directly scoop the water into a bottle, fix it with alcohol and then examine it in the laboratory under a microscope.

A special excursion is carried out along the shore on foot to examine the littoral zone of the lake, i.e., the coastal zone of higher vegetation. Plants are collected for the herbarium, the rhizomes of aquatic plants are dug up, and green filaments are taken into jars. Plant identification can be done using the books of Yu. V. Rychin (1948) and A. N. Lipin (1950) or other plant identification books. Not only older, but also younger schoolchildren (IV grade) can participate in such an excursion, but the teacher can change the excursion program in accordance with the level of knowledge of the students.

The littoral zone with thickets of plants is the most lively and rich in organisms, since plants provide a solid substrate for the attachment of organisms, release oxygen necessary for respiration and, when they die, provide organic remains that serve as food for aquatic animals.

Among the vegetation you can find water beetles and other insects, as well as their larvae, visible with the naked eye or through a magnifying glass.

Before catching animals, the student observes their behavior underwater. He records on what plants or on what soil the specimen was found. On a quiet summer day, the underwater population is clearly visible along the banks of shallow reservoirs. Let students try, by observing a beetle, worm, or insect larva, to decide how this organism feeds, how it breathes, whether it is a predator or whether it itself becomes a victim of others. Back at school, you can look at the characteristics of each organism in more detail under a microscope.

Approximate tasks for individual groups of excursionists may be the following: 1) fishing with nets between plants; 2) scrapings of organisms attached to stems, leaves of plants and underwater rocks; 3) collection by dredging of benthic organisms living in the mud. The material obtained in this way can be easily systematized according to the habitats of animals and relate the distribution of organisms to living conditions.

To extract organisms, the dredged sludge is washed through a sieve (sieve side size 0.5 mm). The sludge should be taken from the surface layer, since this is where the most organisms are found. Usually red bloodworm larvae, worms and small mollusks live in the silt, which need to be examined through a tripod magnifying glass and under a microscope, preferably alive, and before that kept in a jar of water. If the day is hot and the laboratory is far away, they should be preserved in alcohol or other fixing liquid.

When examining the water surface, water striders and small dark shiny whirling bugs catch the eye. Examine a bug's eye under a magnifying glass: when swimming, the lower half of their eye is immersed in water, and therefore is structured differently than the upper half. Of the large beetles, the most common beetles are the water lover, the diving beetle, and their larvae. Water bugs breathe atmospheric air. They are good swimmers, as evidenced by the structure of their limbs (Fig. 11).

Water bugs - smooth bugs, comb bugs, water scorpions - are distinguished by their sucking proboscis at the mouth.

Mollusks crawl on the floating leaves of plants (a large pointed pond snail, a reel, a meadow - all these mollusks belong to gastropods) and the eggs of the mollusks are sometimes attached in the form of transparent mucous strands and rings.

Familiarization with signs of water pollution. When walking around the banks and collecting material, you need to pay attention to whether there are signs of pollution of the reservoir. The teacher, together with the students, can provide direct benefit by reporting the presence of pollution in a given location to the district sanitary inspectorate or the branch of the Society for the Conservation of Nature.

Cemeteries, villages, factories, farmyards - all these are sources of pollution. However, both high school and junior high school students should be aware that river currents sometimes carry pollutants downriver far from sources of pollution and deposit them in quiet pools.

According to the requirements of the state standard (GOST) pure water the reservoir should not have any foreign odor, its color when observed in a layer 10 cm high should not be clearly expressed, and continuous floating films should not form on the surface of the reservoir. These GOST requirements must be taken into account. During the excursion, you can take some water with you into a bottle for testing in the laboratory.

If traces of oil are noticeable on coastal plants and rocks near the shore of a reservoir, if a foreign odor is felt, for example phenol, hydrogen sulfide, oil, etc., films of oil and debris float on the surface of the water, or even clusters of blue-green or black cakes form - this is means that the reservoir is polluted. You cannot drink water from contaminated bodies of water, you cannot swim in them, and samples must be collected carefully so as not to cause harm. A sample from clusters of blue-green algae on the surface of the water should be collected in a jar for viewing under a microscope. Taking into account the degree of contamination by chemical analysis or microscopy of samples is available for students of at least VII grade.

One of the methods for distinguishing clean water bodies from polluted ones is a microscopic analysis of the composition of coastal fouling that forms a border on underwater objects at the water's edge.

Almost clean reservoirs are characterized by bright green fouling of algae from the green group (cladophora, edogonia, etc.) or a brownish coating of diatoms. In clean water bodies there is never the white flocculent fouling characteristic of polluted water bodies.

Blue-green fouling, consisting of algae of the blue-green group (a number of oscillatory species), characterizes not clean, but polluted water (with excess organic pollution). Similar fouling occurs in runoff with excess total salinity.

Fecal wastewater produces white-grayish flocculent fouling consisting of attached ciliates (carhesium, suvoika). Such fouling indicates poor treatment of wastewater after treatment facilities.

Almost no different from them in appearance whitish-fawn mucous deposits of filamentous spherotilus bacteria, also developing in areas contaminated with organic matter. Spherotilus sometimes produces powerful, felt-like cushions.

The entry of toxic waste into a body of water in large concentrations can cause complete or partial death of living organisms. Therefore, comparing the composition of animals above and below the release of polluted water will give us an idea of the degree of harmful influence of the runoff on the reservoir. The complete absence of fouling below the drain also indicates a strong (poisonous, toxic) effect of the drain.

When examining, you should pay attention to the state of higher (flowering) aquatic vegetation - pondweed, reeds, reeds, etc. Toxic wastewater can inhibit vegetation, and, conversely, the presence of biogenic salts (nitrogen, phosphorus, as is the case, for example, in wastewater phosphorite mines) causes excessive development of vegetation.

If familiarization with a lake or river can be continued in winter, then the degree of pollution can be more reliably established. Winter season is, as it were, a touchstone, since in winter the reservoir is isolated from the air by ice and the supply of oxygen in the event of severe pollution may be insufficient for a long winter. With a lack of oxygen, death occurs, and the sleeping fish floats up in the ice holes.

The hottest time for schoolchildren and youth to protect water bodies should be spring, before the flood. At this moment, the snow melts and all the pollution along the banks of reservoirs is exposed. If you do not take care of cleaning the banks in time, then the spring melt water and flood will wash away all the dirt into the reservoir, harming the fishery, and depriving the population of the opportunity to use water for a long time. The task of schoolchildren is to, together with the teacher, under the guidance of a sanitary doctor, organize local residents for timely cleaning of industrial and household waste from the banks of the reservoir.

Pollution of water bodies has a detrimental effect on fish. From a lack of oxygen in the water or a large amount of toxic substances, fish die - suffocation, without visible changes in organs and tissues. When heavily contaminated with toxic substances, fish sometimes rush about randomly, float to the surface, lie on their sides, make sharp movements in a circle or jump out of the water and, as if exhausted, sink to the bottom with their gill covers wide open.

In cases of chronic poisoning of carp, bream, and ide, the phenomenon of dropsy is observed: ruffling of the scales with a large accumulation of liquid under it. Bulging eyes are often noticeable. Noticeable changes and internal organs: the liver, instead of the normal cherry color and relatively dense consistency, becomes dirty-whitish, sometimes marbled, flabby, and in some cases a shapeless mass. The buds also often have an off-white color and a flabby consistency. However, similar changes are also observed when fish become infected with rubella.

All these signs of poisoning can be observed in fish, which the guys can either catch themselves or examine from fishermen. It is also useful to tell fishermen about the listed signs of fish poisoning. Seventh grade students familiar with fish anatomy can lead these conversations themselves.

Processing excursion material

Material Definition. After the excursion, the collected material must be put in order and processed at the school.

Sixth grade students identify aquatic plants using keys. It can be determined not only by flowering specimens, but also by leaves alone (according to the book by Yu. V. Rychin, 1948).

To quickly understand the structural features of organisms, the teacher himself first determines the mass forms, writes down their main characteristics and then distributes to each of the students a specimen of the same species for examination under a magnifying glass or microscope.

As an example, let us consider the larvae of “rocker” dragonflies (with students in grades VI-VII). This is a large larva. It has three pairs of segmented legs, like all insects. The shell of the larva is hard chitinous. Let's plant a living larva in a deep saucer of water and observe its movement. It has a reactive method of movement: a stream of water is ejected from the rear end of the intestine, and the larva thereby jumps forward. Sometimes you can find empty larval skins from which an adult dragonfly has already emerged. The larva has a mask on the underside of its head that covers the lower jaw. If you carefully take a non-living larva into left hand, then you can use tweezers or a stick to pull the mask forward. It serves the larva to catch prey.

If students, due to lack of time, cannot use determiners, then it is enough to tell them the names of individual major representatives fauna and indicate only some of the most characteristic features. It is very useful to sketch animals, at least 2-3 copies. Sketches must be approached strictly: the drawing must be made not from a book, but from nature, resemble the object and reflect characteristic features.

Sixth grade students can examine beetles, water bugs, insect larvae, small mollusks, and leeches under a tripod magnifying glass.

Independent work with a microscope and sketching preparations can be entrusted to older schoolchildren only after they have acquired the skill in a circle.

Under a microscope, they examine: 1) algae that create a bloom in the reservoir; 2) contaminated films with accumulations of algae; 3) filamentous algae; 4) contaminated fouling removed from objects in the coastal part of lakes and rivers; 5) small organs of aquatic animals that are characteristic features species such as mayfly gill filaments; 6) daphnia (they are examined entirely and preferably alive); 7) plankton (considered live or fixed in alcohol in a drop).

Under a microscope, it can be seen that the fouling, which is green in color, consists of filamentous green algae (should be viewed under a high magnification of the microscope; the teacher prepares the specimen). Filamentous algae in each cell have a green chromatophore in the form of a plate, spiral or grain.

Colorless threads of fungi, molds or filamentous bacteria are found in the contaminated area. These threads are very thin, sometimes their diameter reaches only a few microns (1 micron is equal to 1/1000 of a millimeter). The threads show cell division (at high magnification).

Whitish fouling is also found in the contaminated area. Under a microscope, among them one can distinguish ciliates - suvoek, and others that have the shape of a bell, attached by a thread-like leg to a solid substrate.

Observations and experiments on living objects. Some animals can be placed in an aquarium to observe their movement, breathing and feeding. This can be done with beetles, dragonfly larvae, water bugs, mollusks, coil and pond snails. To determine the toxicity of river water as a result of industrial runoff flowing into it, in high schools it is quite possible to conduct a three-day experiment on the survival of aquatic organisms in this water. For testing, it is best to use daphnia, but leeches or mollusks can also be used; Mayfly larvae and bloodworms are not suitable for this, since these latter do not live well in laboratory conditions. Daphnia is caught in any small pond and kept in a jar of clean water until experiment. The water from the reservoir that they want to test for toxicity is poured into small flasks. For comparison, obviously pure river water is poured into other exactly the same flasks. 10-12 daphnia are placed in each cone. Daphnia should be replanted with a small, sparse mesh quickly and carefully, trying not to dry out or crush the crustaceans. Immediately after transplantation, check whether the crustaceans are well preserved, and exclude those flasks where they are poorly preserved from the experiment. In the remaining flasks, observe the state of the organisms for 2-3 days. If daphnia swim normally both in the experiment and in the control, it means that the water is harmless to the reservoir.

Chemical water tests. If the school has a chemical laboratory, it is possible to conduct some chemical analyzes of water, for example, determining the active reaction (acidity and alkalinity) of water. To do this, take one sample from a reservoir near the wastewater discharge and, for comparison, another from its clean area. To both samples add 2-3 drops of the indicator methyl orange, which changes color from red in an acidic environment to yellow in an alkaline environment. In case of contamination with industrial wastewater, the color of the test and control samples will be different.

The color of water is determined in cylinders 10 cm high, comparing contaminated water with distilled water.

Determination of the hardness of water from a well is carried out with soap foam. You need to make a solution of soap in alcohol. Pour water from different wells into a row of cones or bottles, and distilled water into one of them. Then you should gradually add a soap solution from a burette or pipette, shaking the liquid in the flask. In distilled water, foam is formed from a few drops of soap, and the harder the water, the more soap is needed to form foam.

Material design. The materials collected during the excursion are prepared for the school museum as follows.

Aquatic flowering plants are collected in a herbarium on sheets in a folder or on a stand under glass. You can make a poster diagram of the distribution of aquatic vegetation of a pond by zone (see Fig. 4).

The results of surveying the plan of the pond and measuring the depths are drawn in the form of a schematic drawing, as well as a model of the pond, with the coastal landscape and coastal settlements depicted.

Calculations of the area of the lake, the amount of water in the lake, water flow in the river, and river flow speed can be compared with measurement data from the regional water metering station.

Collections of aquatic insects are made dry on pins in boxes; insect larvae are stored in test tubes or jars with alcohol, filled with paraffin, with labels.

Drawings of microscopically small forms and drawings made when identifying species, indicating distinctive features, are issued in the form of an album. An album or exhibition of photographs taken by the students themselves at the pond is also compiled.

The final conversation of the teacher is devoted to the national economic significance of this reservoir, the possibility of raising fish or fishing in it, the degree of pollution of the reservoir and measures for its protection.

Literature

Gribanov L.V., Gordon L.M., Increasing intensity is the main thing in the development of pond fish farming in the USSR, Sat. "The use of ponds for intensive fish farming, M., 1961.

Dorokhov S. M., Lyaiman E. M., Kastin B. A., Solovyov T. T., Agricultural fish farming, ed. USSR Ministry of Agriculture, M., 1960.

Eleonsky A.N., Pond fish farming, Pishchepromizdat, M., 1946.

Life of fresh waters of the USSR, ed. Zhadina V.I., ed. USSR Academy of Sciences, M. - L., 1940-1956.

Kulsky A. A., Chemistry and water treatment technology, 1960.

Landyshevsky V.P., School and fish farming. State uch. ped. ed., M., 1960.

Lipin A.N., Fresh waters and their life, M., 1950.

Martyshev G.V. et al., Pond fish farming on collective and state farms, 1960.

Polyakov Yu. D., A manual on hydrochemistry for fish farmers, Pishchepromizdat, M., 1960.

Raikov B. E. and Rimsky-Korsakov M. N., Zoological excursions, 1938.

Rychin Yu. V., Flora of hygrophytes, 1948.

Skryabina A., My work with the young people, ed. "Young Guard", 1960.

Cherfas B.I., Fish farming in natural reservoirs, Pishchepromizdat, M., 1956.

Zhadin V.I., Gerd S.V., Rivers, lakes and reservoirs of the USSR, their fauna and flora, Uchpedgiz, 1961.

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