“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
Of the 1018 tons of water on Earth, only 3% is fresh water, of which 80% is unusable because it is ice that forms the polar caps. Fresh water becomes available to humans as a result of participation in the hydrological cycle, or the water cycle in nature, which is schematically depicted in Fig. 12.3. Every year, approximately 500,000 km3 of water is involved in the water cycle as a result of its evaporation and precipitation in the form of rain or snow. Theoretically, the maximum amount of fresh water available for use is approximately 40,000 km3 per year. We are talking about the water that flows from the surface of the earth into the seas and oceans (the so-called runoff).
The water cycle in nature has been known since Old Testament biblical times:
“All the rivers flow into the sea, but the sea does not overflow,
To the place where the rivers flow -
They keep running there."
Book of Ecclesiastes, 1:7.
Rice. 12.3. The water cycle in nature.
The use of fresh water is usually divided into repeated use and irreversible consumption. In accordance with this, fresh water is also sometimes divided into reusable and irretrievably consumed.
Reuse of water can be illustrated through examples such as navigation, fish farming and hydroelectricity.
Irretrievably consumed fresh water becomes no longer available for reuse. This includes fresh water, which, after consumption, was lost as a result of evaporation (including by plant leaves); water included in the products, as well as runoff water that reached the sea (ocean) and mixed with salt water. The consumptive consumption of fresh water worldwide ranges from 2,500 to 3,000 km3 per year, of which approximately 10% is used for domestic purposes, 8% for industry, and the vast majority - 82% - for irrigation in agriculture.
Water consumption
Water consumption for domestic purposes. 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 230 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 and agriculture. Agriculture accounts for 82% of the world's water use. 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 to generate hydropower. Over 50% of the UK's total water supply is used in power stations. Water is used in hydroelectric power plants, as well as in 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 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.
The distillation of water in them is carried out under reduced pressure. However, this method requires a lot of energy and is only economical in countries such as Kuwait, where energy is available at relatively low prices and rainwater is extremely scarce.
Fresh water can also be obtained using electrodialysis (see Section 10.3) from brackish 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.
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 issues
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 back; 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 |
How we use water
Water is our most priceless resource. It is vital. People, plants and animals are mostly made of water. All living things would die if there was no water. We use water for drinking, washing, cleaning, cooking and growing plants, and many other things. The average person uses approximately 150-250 gallons of water daily. Even more water is used by industry to produce electricity, goods and for transporting people and goods.
To meet household needs, a lot of water is needed. A bath may require 30 to 40 gallons. The average toilet uses about 5 gallons at a time. 20-40 gallons goes into a shower. Washing machines use an average of 25 gallons per load. The kitchen sink uses approximately 20 gallons per day for preparing water and washing dishes. The bathroom sink, which is used for washing hands, shaving and brushing teeth, wastes 15 gallons every day.
Most fresh water is also used for watering lawns, flower beds, vegetable gardens, as well as for washing cars and filling swimming pools. We must be careful not to pollute the water we use outdoors. Many people use chemicals on their lawns and gardens and then water them with clean water. The water will wash away the chemicals from the plants and then flow into the sewer system, and then directly into the rivers and tributaries where the fish lay their eggs. This polluted water can kill fish and wildlife. We should always make sure not to pollute the environment.
We must protect water and not abuse it. Every city, small or large, uses water. Cities use water to fight fires, wash streets, and water public spaces such as parks, lawns, trees, shrubs, and flower beds. The water is also used to fill public fountains and drinking water sources, including those located at schools and libraries. Various industries also use water. Think about the water that businesses in your city use. Restaurants, hospitals, laundries, dry cleaners, golf courses. Various hotels, car washes, beauty salons, hairdressers, gas stations, fitness clubs. They all increase water consumption. We need to think about the number of people who need to use the water and conserve it so that there is enough for everyone.
The amount of water required for the farm is amazing. When we think of water on a farm, we think of watering crops, but large amounts of water are also needed for a dairy farm. Chickens, piglets, sheep and all other barnyard animals need drinking water in order to live. They need to grow food, and they also need water to keep the meat fresh in the cooling systems. Vegetables and grains also need water. Water is used to spread fertilizers, herbicides and pesticides, which help produce more crops but can also pollute the water. Most of the water consumed on a farm is used for irrigation. Research shows that with drip irrigation, farmers can save up to 60% of water compared to other irrigation methods.
It takes about 26 gallons of water to grow one ear of corn, while it takes 2,000 to 2,500 gallons of water to produce one pound of beef. Approximately 120 gallons of water are needed to produce one egg. Approximately 300 gallons of water are required for one loaf of bread and approximately 12,000 gallons to grow one bushel (about 9.3 gallons) of wheat. Believe it or not, approximately 1,400 gallons of water are used in the process of preparing a fast food item, including a sandwich, fried meat, and soft drink.
Hydroelectric power plants are the consumers of the largest amount of water.
Hydroelectric power plants capture the kinetic energy of the supply water in order to produce electricity. They do this with the help of a dam. A dam causes water to rise and thus the water will have more energy when falling. The force of the falling water puts pressure on the turbines, causing them to begin to rotate. Rotating turbines transfer the kinetic energy of falling water to generators. The generators spin when the turbines spin, thereby producing electricity that is then transmitted through power lines to homes and businesses.
Of the total electricity in the world, approximately 20% comes from hydroelectric power plants. Approximately 10% of all electricity is produced by hydroelectric power plants. Hydroelectric power generation prevents much of the pollution. Hydroelectric power generation is by nature a clean production method and does not leave any waste. Electricity produced by hydroelectric dams reduces the amount of oil and coal needed to meet electricity needs. It eliminates the need to burn approximately 22 billion gallons of oil or 120 million tons of coal each year. The amount of energy a hydroelectric plant can supply depends on two things: the height at which the falling water is located and the amount of falling water. The higher the dam, the longer the water falls and the more energy is produced. If the height is doubled, then the amount of energy produced will be doubled. The amount of water falling also affects the amount of energy produced. The more water that flows through the turbines, causing them to spin, the greater the amount of energy produced.
Water is also needed in industry. It is heated, and the steam is used to start the equipment. Water is used to cool hot metals, such as in steel production.
Water is also used to cool the air. It is an important element in many chemicals, such as medicines, lotions, shampoos, cosmetics, cleaning products and also drinks. Water is used in food preparation and countless processes in factories, including paper production. Water used in processing food and drinks must be absolutely clean. And manufacturing enterprises may use water of lower quality.
Recreation is another area where we use and enjoy water. Many people enjoy fishing, boating, sailing, canoeing, rafting, swimming, and many other recreational activities that depend on the water. Most of us enjoy at least one of these holidays and would be disappointed if we were never able to enjoy any of them again. If our water is constantly polluted, then it becomes dangerous to simply swim, and the extinction of fish in reservoirs would deprive us of fishing. No one would be able to enjoy boating, sailing, canoeing, or rafting in polluted water. We must remember that it is very important to protect water from pollution.
Transportation is another way to use water. Many people use boats and ferries to get to and from work. People also enjoy cruising or just sailing. Shipping damage includes fuel spills that coat the water with oil and coal dust, and shoreline erosion that harms fish and other aquatic life.
Instructions
First of all, a person uses water for food: he quenches his thirst with it, and prepares dishes with it. Scientists have found that for the normal physical condition of all human organs, it is necessary to drink 1.5-2 liters of water per day, not counting the juices and other liquids drunk during the day.
Personal hygiene cannot be accomplished without water. Washing requires up to 10 liters of water per person, when using a toilet in a house with forced sewerage - up to 45 liters daily, on average up to 190 liters are allocated.
Owners use water to clean their premises. It is estimated that on average, up to 180-200 liters of water per day are spent on washing dishes, floors, windows, laundry, and watering indoor flowers.
Water is used widely in rural areas and in agriculture. Also, every year during the season, summer residents use large quantities of water to water their gardens.
When extinguishing fires, it is impossible to do without large volumes of water, since water in such cases is used both as a coolant and as an insulating liquid in the foam composition (it does not allow air flow to the open fire).
Water is also used as the main coolant. For this purpose, it is used in heating networks and heating mains. Water is used as ice to cool various catering systems and for medical purposes.
It is difficult to imagine many sports without water, such as swimming, water polo, rowing, hockey, curling, and others. Healthy relaxation also includes the opportunity to visit a bathhouse, sauna, water park, swimming pool, where you can’t do without water.
note
Fresh water occupies only 3% of the total volume of water resources in the world. The largest portion of all fresh water on earth is contained in glaciers in the polar regions.
Within the boundaries of the earth's biosphere, water is the most common substance. It is found in both free and bound states. This liquid is the basis of life on the planet. The remarkable properties of water have become the reason for its widespread use in everyday life, production and many other areas of human activity.
Instructions
Water is not only the source of existence for most living organisms; since ancient times it has been one of those substances without which economic processes cannot operate. Rarely does any technical system operate without the participation of this universal liquid. Water is one of those substances that naturally exists on the planet in all three states of aggregation: liquid, gaseous and solid.
Experts know that the main feature of water is the uniqueness of its properties. Almost all of these characteristics are anomalous from a scientific point of view. Water easily changes its states, for example, moving from the liquid phase to the solid or gaseous phase. This liquid is sensitive to magnetic fields and is capable of conducting electricity.
One of the main properties of water is that it increases its volume by about 9%. If this process takes place in a confined space, colossal forces develop, which are successfully used in technical devices, for example, in ice jacks or cold welding machines. This property allows you to develop significant pressure in a small space.
The most common liquid on the planet also has high thermal conductivity, becoming a kind of thermal energy accumulator. There are original heating systems that use this property. In summer, the water in such installations is heated by interaction with the exhaust gases of diesel engines, after which the liquid is pumped into underground storage. In winter, the remaining warm water is supplied to the heating system of the houses.
Water absorbs gases very well. At the same time, up to several tens and even hundreds of volumes of various gases can be dissolved in one conventional unit. If gas is present in the water, a cavitation effect may occur. In places where liquid moves at high speed in a narrow space, water boils and gas bubbles form.
It is difficult to find a solvent better than water. Almost all elements of the periodic table are found in the waters of the planet in a dissolved state. This quality is explained by the high dielectric constant of this liquid. Absolutely pure water is extremely difficult to obtain; it will almost always contain impurities of other substances.
Water has a truly magical property. It has been established that under the influence of a magnetic field, water can change its characteristics. At the same time, the rate of chemical reactions accelerates, salts dissolve faster, and crystals precipitate more rapidly from supersaturated aqueous solutions. Engineers know: to make the technological process in which water is involved more intensive, it is necessary to introduce a magnetic field into the system.
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Water is the basis of all life on planet Earth. It occupies 2/3 of the surface of the entire planet and is involved in many processes and reactions. It’s not for nothing that water is called the source of life.
Instructions
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Water as a substance is used in many areas of human life. It is used in utilities, manufacturing, industry, air conditioning systems, etc.
Instructions
Water is the most valuable natural resource of great importance in the life of mankind. It is the only substance in nature that can exist in three physical states: ice, liquid and gas. Water is capable of absorbing large amounts of thermal energy without significantly increasing its own temperature, which ultimately determines the planet's climate. Ordinary clean water contains hydrogen and oxygen. It has a bluish tint and is very difficult to compress.
Water has many uses, each of which has a major impact on the physical and economic well-being of humanity. The largest amount of water is used by public utilities. In particular, the air humidity necessary for the normal functioning of mankind is maintained, air conditioning is provided, and water is required for the operation of such equipment. It cools the heat exchangers of air conditioners and creates the necessary indoor climate in hot weather. It heats houses and public buildings. The maintenance of plant life is based on water, which is provided to them by nature itself.
Man cannot live without water. It cleanses the blood and removes waste products from the kidneys. It is used for preparing food and drinks, during bathing, washing, washing dishes and food. Plumbing equipment requires the use of water as a carrier for waste from sewer systems. There is nothing to replace it when irrigating lawns, bushes and trees in the summer months. Water is used in fire protection. It is important to ensure uninterrupted supply, sufficient capacity and appropriate power of water mains for its unhindered delivery to all places of human settlement and protection from fire.
A fairly large number of outdoor activities involve the use of water. Examples include rowing, swimming, fishing and other water sports. Water is widely used in production and industry, as well as in medicine. There is a whole area called hydrotherapy. It involves the external use of water at different temperatures for therapeutic and prophylactic purposes. The physiology of the action of hydrotherapy procedures is determined by the nature of the irritations that they exert on the skin, and through it on the entire body of the patient.
Scientists have proven that water is capable of carrying information. She has a memory, so water is often used in magical rituals and conspiracies. It is believed that “living” water, found naturally in Tibet, can improve a person’s aura. And “dead” - poison the body and contribute to its early aging.
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