For what needs does a person use fresh water? Rational use and protection of water resources - Knowledge Hypermarket. What determines a person's daily water consumption?

Purpose of the lesson: to form in students an idea of ​​water consumption and the current state of the aquatic environment, as well as the main environmental problems associated with the economic use of fresh water sources, and rational water use.

Equipment and materials: technical teaching aids (projector, computer, electronic presentation of lessons), illustrative material, task cards, Whatman sheets, markers.

Completing tasks

Exercise 1. Remember the properties of fresh water.

List the physical and chemical properties of water that you know and write them down on whatman paper. Remember the meaning of key concepts: water cycle, water supply, wastewater discharge. ( Three states of aggregation of water, water density 1 g/cm 3, ice formation at a temperature of 0° C, boiling at 100° C, transparency, ability to dissolve substances, necessity for life support.)

Task 2. What bodies of water are considered fresh?

Remember and list the types of fresh water bodies. ( Rivers, streams, lakes, ponds, swamps, canals, groundwater. It should be recalled that bodies of water can be either of natural origin - rivers, lakes, swamps, or created by man for a specific purpose - ponds, reservoirs, canals). Which of the listed reservoirs may be suitable for water use, and which are not, and why? ( The most suitable are rivers and underground springs.)

Task 3. How and for what is fresh water used?

List all possible household needs for which a person uses water, and arrange them in the form of a pyramid.

Explanation of new material

1. Sources and uses of fresh water

People use fresh water for various economic needs, the main ones being agricultural irrigation and energy production. To a lesser extent, water is consumed in industry and for domestic needs, including drinking water. Terrestrial natural waters (mainly rivers, lakes) and groundwater are used as sources of fresh water.

2. We “borrow” water from Nature

All the water we use is removed from the natural water cycle and returned to it already polluted, with a large amount of waste. Domestic and municipal wastewater enters rivers, bays and seas through the city sewerage system. Industrial enterprises, as a rule, are located on large natural reservoirs, where they receive an unlimited amount of water, use it and discharge it along with waste. Water runoff from fields, along with the fertilizers and chemicals contained therein, also pollute natural waters.

3. Environmental problems

Using water for economic purposes gives rise to the following problems.

A. Natural springs can only provide a limited amount of water. There is a danger of overuse of river water and significant changes in the ecosystems of the catchment areas. For example, draining water from a river can affect the condition of adjacent swamps and floodplain meadows - they dry out because... are not fed by periodic floods; as a result, the species composition of such ecosystems changes.

B. The use of groundwater leads to a reduction in its supply and subsidence of the soil. Groundwater is 70 to 80 times larger than surface water, but groundwater is also depleted if it is consumed faster than it is replenished. As the volume of groundwater decreases, a gradual lowering of the land surface, called subsidence, can occur. In populated areas, this leads to the destruction of roads, building foundations, water supply and sewerage networks, and on the coasts - to flooding and destruction of the coastal zone.

IN. The water that returns to nature is heavily polluted. This is dangerous both for human health and for the environment, especially water bodies. The wastewater of an average-sized city contains the following pollutants:

– soil washed away during the destruction process;
– residues of fertilizers, insecticides and herbicides used in gardens and parks;
– various chemical compounds formed during road surface wear;
– soot and toxic substances from vehicle exhaust gases;
– fuel and engine oil from roads and parking lots;
– garbage and plant debris;
– waste water from residential premises and enterprises;
– waste from industrial enterprises that use water (the largest amount of pollutants comes from pulp and paper production).

Surface and groundwater pollution

G. Bioaccumulation of toxic substances contained in water. The greatest problem in the pollution of natural waters is caused by various toxic chemicals contained in domestic, industrial, agricultural and other wastewater. They are present in low concentrations, are difficult to remove from waters, and can accumulate for a long time in living organisms.

Most pollutants belong to two groups: heavy metals (lead, mercury, cadmium, iron, chromium, etc.) and synthetic organic compounds (benzene, phenol, dioxins, hexachlorocyclohexanes, chlorinated biphenyls and many others). All toxic chemicals present in the environment in small doses over a long period are dangerous due to their ability to accumulate in the body, which leads to mutations, cancer, and various pathologies.

In nature, toxins move through food chains, at the last links of which their concentrations can increase hundreds of thousands of times compared to the environment.

Completing tasks

Task 4. Draw up a diagram of the water cycle, taking into account all types of its “withdrawal”, use and discharge of polluted water (various types of pollution - industrial, agricultural, household, etc.) back into natural reservoirs. You can complete this task first on whatman paper or a blackboard, and then in notebooks. Start your diagram with a typical water source—a river.

Main conclusion: clean water is taken from a closed cycle of the water cycle, and contaminated water is returned; pollution enters natural reservoirs, from where water is taken back for use. Increasing levels of pollution in natural water bodies have a detrimental effect on living organisms and the quality of drinking water.

Task 5. Survey students in your group using the following questionnaire and analyze the situation with drinking water consumption.

– Who drinks tap water at home, and who buys it in bottles?
– Who has ever drunk water in other Russian cities? In other countries? How different is our water from foreign water?
– Do you use filters to purify water at home?

Explanation of new material

4. Delivery of water to the consumer

(To be carried out using handouts.)

Water used for domestic purposes is usually taken from a river or from underground sources in the area of ​​water intake. In the Kaliningrad region this is the Pregolya River, a group of drinking lakes and groundwater in some places in the region. Water purification and preparation usually follows the following scheme:

reservoir ––> coarse filters to remove large impurities ––> reservoir for settling water (small impurities are removed) ––> water disinfection to destroy pathogenic microorganisms (usually chlorination) ––> flocculation (sedimentation of suspended substances in water on aluminum hydroxide sediment ) ––> passing through sand filters ––> purified water reservoirs ––> water supply network ––> consumer.

Figures and facts:

– the average Russian consumes 272 liters of water per day;
– about 50 million people in our country drink water with a high iron content;
– in recent years, about 750 chemical compounds have been discovered in water bodies, of which 600 are carcinogens and are practically not neutralized at water supply stations.

5. Be careful! Tap water!

The main reasons for the low quality of drinking water from the tap are:

– contamination of water intakes;
– use of chlorination;
– poor quality of water supply networks;
– imperfection of sand filters.

The greatest danger in the preparation of drinking water is the technology of chlorination, since it leads to the appearance of so-called “bound chlorine” in the water - the result of the interaction of chlorine and some organic compounds. Among the products of chlorination there are carcinogenic and toxic compounds that are odorless and practically cannot be removed by boiling and settling water (these include substances such as lindane, dioxins, butyl chloride, trichlorophenol, etc.).

The contamination of drinking water also depends on what material the water pipes are made of. For example, cast iron water pipes laid more than 80 years ago still work properly. But the steel pipes laid in the 1970s. have already caused a lot of trouble. In addition, due to the poor quality of the pipes, the iron content in the water exceeds GOST standards.

Final tasks

Task 6 (performed in groups). On the already analyzed “water withdrawal” diagram, find the areas that correspond to the greatest contribution to water pollution (both natural and consumer). Suggest how you can minimize the harm caused to nature and human health.

Task 7. Alternative water sources.

(Students are given cards with images of alternative sources of water supply: forest lakes, swamps, underground sources.)

Provide an analysis of the pros and cons of a particular alternative source compared to those currently in use using the following criteria:

– purity of water at the source;
– source power (whether there is enough water to supply the city);
– convenience of water intake;
– delivery of water to consumers.

Main conclusion: the optimal solution to water supply problems is to improve the environmental condition of currently existing water sources.

Task 8. Purifying tap water at home.

At home, you can very simply organize water purification using the freezing method (recrystallization). Choose an enamel pan with a lid that fits in the freezer compartment of the refrigerator. Fill the pan with boiled water at room temperature so that there is a gap of 3 cm between the lid and the water (in this case, the water will freeze from the bottom and sides, but under the lid itself will not have time to freeze in a day). The water should freeze by half or two thirds. In the center of the pan there will be unfrozen brown water containing impurities. This water must be drained, the remaining ice must be washed and melted. It should be remembered that the resulting water is close in composition to distilled water, and does not contain calcium, magnesium, etc. salts, so before using this water for drinking, it is necessary to compensate for their deficiency.

Handouts for the lesson

Water intake station - lifting water to treatment plants	Using Pumps	Consumes a lot of energy
Removing large debris and particles contained in water	Passing water through special grates
Water settling tank	Small impurities are removed
Water disinfection (chlorination)	Adding chlorine from cylinders, chloramine or sodium hypochlorite	Chemical consumption
Flocculation	Precipitation of impurities using aluminum hydroxide	Chemical consumption
Passing through sand filters	Removal of residual suspended particles and impurities
Purified water tank	Water is prepared for sending to the water supply network
Water supply network – sending water to the consumer	Pumps pump purified water into the water supply network	Consumes a lot of energy

Humanity consumes huge amounts of fresh water. The most water-intensive industries are: mining, steel, chemicals, petrochemicals, pulp and paper, and food processing. They consume 70% of all water used in industry. But still, the main consumer of fresh water is agriculture, which takes 60–80% of the fresh water used by humans.

Water is a necessary component of human life. How does a person use water?

Water is a universal solvent; all biochemical and metabolic reactions in a living organism occur with its participation.

1. A person should drink from 0.5 to 2 liters of water per day.

2. Water is necessary to maintain hygiene of the body, home, and street.

3. Water circulates in heating plants of cities and towns.

4. Mineral waters are consumed internally and for baths, using their healing properties.

5. Hot water from thermal springs is used to heat housing, greenhouses, greenhouses, and generate electricity.

The growth of cities, the rapid development of industry, the intensification of agriculture, the expansion of irrigated areas, and the improvement of cultural and living conditions are increasingly complicating the problem of water supply. The demand for water is enormous, and its costs are increasing every year. So, if for household needs in houses without sewerage a person consumes about 50 liters of water per day, then in modern buildings the water consumption per person per day is 200–500 liters.

Most of the water, after being used for household needs, is returned to rivers in the form of wastewater. The shortage of fresh water is already becoming a problem; countries such as Germany, France, England, Belgium and others (more than 50 countries in total) are already experiencing water shortages. Some African countries import fresh water in the form of icebergs.

Sources of replenishment of drinking water.Open waters – rivers, lakes, springs. To obtain drinking water from these sources, additional purification is required.

Precipitation - almost distilled water, which does not contain essential trace elements. In addition, when passing over populated areas, precipitation becomes contaminated with dust, dirt, gases, and various microorganisms. As a result, such water is not suitable for drinking.

Artesian waters, formed from groundwater - as a rule, this is clean water, but characterized by increased hardness. Even artesian water can be contaminated through cracks in the earth's rocks, abandoned mines, etc.

People are concerned about the quality of the water they use, since this is one of the components of the environmental health of the population. The main “environmental” diseases come from air and water pollution. Causative agents of infectious diseases (typhoid fever, cholera, dysentery, tularemia) can be transmitted through water. Water can also be a source of infection with helminths and malaria. If in some area there is not enough iodine in the water, then the residents of the area suffer from endemic goiter. An excess of fluoride in water causes endemic fluorosis, i.e., human teeth and bones become fragile, the osseous-ligamentous apparatus is affected, and a lack of fluoride increases the incidence of dental caries, mainly in children.

Sea water pollution. The quality of water used by humans has sharply decreased due to the discharge of chemical plants, household waste and other pollutants into fresh and sea waters. As a result of the entry of significant amounts of toxic and anthropogenic waste into the waters of the seas and the World Ocean, the self-purifying properties of sea waters are reduced and their biological productivity is reduced. There are three types of sea water pollution: chemical, household waste, and radioactive.

Chemical pollutants – This is mainly oil and oil products that have entered the sea as a result of drilling wells or tanker accidents.

Pollution from household waste leads to the occurrence of infectious diseases in swimmers, changes in aquatic flora and fauna.

Nuclear pollution - this is pollution in which the concentration of radionuclides accumulated by planktonic organisms is several times higher than the radioactivity of water; sources of pollution: waste from nuclear submarines, uranium ore purification plants, nuclear power plants.

Pollution of inland water bodies. Due to the rapid development of industry, deep rivers and lakes are disappearing, and their salt composition is changing dramatically. Thus, Rhine water cannot be used for drinking; it is even dangerous to brush your teeth with this water, since German and French concerns dump untreated waste there. The Weser River has been turned into a sewer, and the waters of the Elbe are saturated with toxic substances. Almost all rivers in England are polluted. None of the Moscow rivers meets sanitary standards.

Harmful pollutants of inland waters are phenol and its derivatives, as well as surfactants contained in modern detergents. The pollution of water bodies with pesticides and mineral fertilizers coming from fields with rain and melt water is of serious concern.

Ways to protect water resources– introduction of new technological processes, transition to closed (drainless) water supply cycles, where wastewater is not discharged, but is reused.

Currently, wastewater treatment is carried out using mechanical, chemical and biological methods.

With the mechanical method They use a system of settling tanks and various types of traps (sieves, grates, sand traps, grease traps, etc.).

With the chemical method Reagents are added to wastewater to form an insoluble sediment with pollutants.

With the biological method For the mineralization of organic pollutants, aerobic (i.e., occurring in an oxygen environment) biological processes carried out by microorganisms are used. Thus, in sugar factories, wastewater is purified using the single-celled green algae chlorella. Specially prepared areas are created - irrigation fields, biological filters. This method gives the best results.

In agricultural irrigation fields, contaminated water is filtered through the soil, and a significant amount of valuable organic fertilizers accumulates.

Water is the main component of the hydrosphere, the main environment-forming component, an integral part of living matter. Despite the large reserves of fresh water on Earth, their shortage for humans and many ecosystems is real. By depleting and polluting water, a person not only deprives himself of this resource, but also destroys the living environment of many organisms and disrupts their inherent connections.

1. Give examples of the features of the aquatic habitat and the characteristic features of the inhabitants.

2. Justify why pollution of aquatic habitats is dangerous for living organisms, give examples.

3. Explain the importance of water in the life of any organism; support your answer with examples.

4. Prove that water is the most severe limiting factor.

5. Comment on whether water is an inexhaustible resource.

6. Name where the reserves of accessible and inaccessible fresh water are concentrated.

7. Describe the water cycle in nature.

“Water pollution and protection” - Article 77. Article 76. 1 geography textbook – 0.5 cubic meters. Water pollution. Antoine de Saint-Exupery. Water, you have no taste, no color, no smell. Untreated wastewater from populated areas threatens the spread of dangerous infectious diseases. Water protection. You are the greatest wealth in the world. Article 78. Water needs purification.

"Baltic Sea" - Oil pollution. Problems of the Baltic Sea. Action plan for the protection of BM. Death of natural fauna. Location of the Baltic Sea. Pollution is distributed fairly evenly. The concentration of pollution almost everywhere remains within 200 grams per 1 square meter. meter. High degree of toxic pollution.

“Ocean Pollution” - Construction of wastewater treatment plants at enterprises. Ocean pollution is the result of human activity. People, don't hurt Nature! Causes of pollution of the World Ocean. The topic of our research is “Pollution of the World Ocean.” The work was carried out by 4th grade students of Municipal Educational Institution Secondary School No. 6. Effective chemicals are used to destroy traces of petroleum products.

"Water and Pollution" - Pollutants can be divided into several different classes. The fourth class is infectious organisms and pathogenic microorganisms. Water pollution. Many petroleum products are poisonous to animals. Nitrates can cause death from anemia in infants. And the last class (fifth) is thermal pollution.

“Water pollution by humans” - In this way, surface, underground, and groundwater are polluted. Water in human life. Causes and sources of pollution. Water pollution has many causes. The origin of pollution can be: municipal (sewage), industrial, agricultural, natural. Types of water pollution and diseases caused.

“Water pollution” - 1) biological. (when polluted by surface wastewater). Thirdly, water from the thermal power plant, entering the reservoir, leads to an increase in t 0 C of the water in it. No. 3. discharge of undissolved materials – clays, as industrial waste – into water bodies. Thermal pollution. Secondly, the fine clay fraction settling to the bottom will destroy the spawned fish eggs.

There are 11 presentations in total

Domestic water consumption. For domestic purposes, water is used for drinking, cooking, washing, washing, flushing sewage into sewers and watering gardens and streets. In Europe, the average domestic water consumption per capita is approximately 250 liters per day. This is approximately the same as during the Roman Empire. Approximately 10% of all water consumed by humanity is consumed for domestic purposes..

Water consumption for industrial purposes. Over 85% of water used for industrial purposes is consumed in cooling processes. The rest is consumed in washing processes, gas scrubbing, for hydraulic transport and as a solvent. Approximately half a million liters of water are used to produce each passenger car; this amount includes both wasted water and reused water. Approximately 8% of all water used in the world is consumed for industrial purposes.

Water consumption in agriculture. Agriculture accounts for 82% of water use worldwide. This water is used for irrigation. Growing one ton of cotton requires 11,000 million liters of water. Growing a ripe pumpkin requires 150 liters of water.

Water consumption for hydropower generation. Over 50% of the UK's total water supply is used in power stations. Water is used in hydroelectric power plants, as well as thermal power plants, to create steam that rotates turbines, and for cooling purposes. Although power plants consume huge amounts of water, it is used with virtually no losses, in a closed cycle. It is estimated that by the mid-twenty-first century, water consumption throughout the world is expected to exceed natural supply. To solve this problem, various methods of obtaining fresh water are being developed, which are described below.

Increased freshwater inflow. Most of the water flowing from the surface of the earth into the oceans is wasted, useless for human needs. Building reservoirs and drilling wells to extract groundwater increases the amount of water used by humans before it ends up in the oceans. During hot weather, large quantities of water are lost from lakes and reservoirs through evaporation. This can be prevented by covering the surface of the water with a thin film of 1-hexadecanol alcohol.

Use of sea water and brackish waters. Fresh water can be obtained from sea water by desalting as a result of vacuum distillation in evaporators.

Fresh water can also be obtained using electrodialysis from salt water. Such water is found in river mouths; it has a salinity intermediate between fresh river water and salt sea water.

There are currently over 2,000 desalination plants operating worldwide. To desalt water, not only vacuum distillation and electrodialysis methods are used, but also freezing methods, ion exchange and reverse osmosis.

O.V.Mosin

Water.

Filtering fields. Biofilters.

Azrotenki.

Careful use of fresh water, timely and effective wastewater treatment, and protection of water resources reduce their scarcity and increase their potential.

use.

■ Examples and additional information

1. The main part of water resources used by humans is river runoff. The total annual flow of rivers on our planet is 37 thousand km3. An underground river flows under almost every river, and the underground annual flow is 13 thousand km3. The supply of fresh water varies from country to country. The richest countries in fresh water are Brazil (5668 km3 per year) and Canada (9740 km3 per year). In our country, the annual river flow is 4384 km3 per year. Many countries lack fresh water and import it. Water is transported tens and hundreds of kilometers through pipelines, transported by ships, vehicles and even airplanes. Residents of Algeria, Holland, Hong Kong, and Singapore use imported water. According to the World Health Organization, approximately 1.2 billion people suffer from a lack of clean drinking water.

2. In agriculture, water is used in huge quantities: 70% of all water consumption. The following irrigation standards have been established for the main agricultural crops (R M,! on

1 ha): grains - 1500-3500, perennial grasses - 2000-8000, cotton - 5000-8000, rice - 8000-15,000.

3. In public utilities, water is used for household needs of the population, for the operation of consumer service enterprises, washing streets and watering green spaces, and for fire prevention measures. This represents approximately 15% of industrial water consumption.

It is believed that in a well-maintained city, each resident uses 200-300 liters of water per day for personal needs. One resident of Moscow needs over 400 liters of water per day, and one resident of St. Petersburg - more than 300 liters. In London, each resident uses 170 liters of water per day, in Paris - 160 liters, in Brussels - 85 liters.

4. Methods for determining the degree of pollution of water bodies are different. This can be a direct measurement of the concentration of pollutants (for example, heavy metal salts). The content of organic substances is often determined by the amount of 02 absorbed by a certain volume of water per unit of time; during bacteriological analysis, the number of bacteria in 1 cm* of water is determined when colonies are grown on

nutrient media in the laboratory. The degree of water pollution can be

also determine the species diversity of aquatic biocenoses. About 800 inhabitants of freshwater bodies are very sensitive to the presence of organic substances in water, they serve as indicators of well-being in aquatic ecosystems.

5. After a high-profile trial in 1971, the well-known Ku-

Minamata disease became a mulative (cumulative) disease. In the 1950s the ore processing plant dumped waste,

containing mercury into the waters of Minamata Bay (Japan). Bacteria processed it into dimethylmercury. It entered the food chain and accumulated in fish up to 50 mg/kg. People eating fish suffered severe poisoning, nerve diseases, and more than 50 people died. From 1955 to 1959, every third child here was born with mental and physical abnormalities. Fishing in the bay is still prohibited; It is believed that there is about 600 tons of mercury at the bottom of the bay. Minamata disease is included in all reference books as an example of a disease caused by environmental pollution and the accumulation of mercury along food chains.

6. An example of the successful use of recycled water in motor vehicles is the closed-loop system “Crystal”. In it, the water used for washing cars is supplied to vibration filters, where it is cleaned of coarse suspensions and sand. Then it enters filter columns filled with synthetic material - siprone, which absorbs petroleum products. Purified water is collected in tanks and reused for car washing. Reuse

of post-treated wastewater reduces the consumption of fresh water by 20-25 times

water and reduces wastewater discharge into water bodies.

Q Questions. 1. Find in the reference book a description of the physical and chemical properties

1 in water: states of aggregation, density of water and ice, boiling and melting points, specific heat, heat of evaporation, dielectric

permeability, etc. How do these properties determine the role and functions of water in nature and living organisms? 2. For what needs does a person use fresh water?

3. What substances are most dangerous when polluting water bodies and why? 4.

How can you determine the degree of pollution of a river or lake? 5. How is the regionality rule applied when using water resources? 6. Why is water consumption