The world is 97% salt water. Fresh water is only 3%. Russia is one of the world leaders in terms of water reserves. Our country is distinguished by an abundance of natural waters, a well-developed river network, as well as a unique water coast with a length of about 60 thousand kilometers. Static (century-old) reserves of fresh water in all its sources and forms in our country are about 90 thousand km3/year. However, having such significant water resources and using on average no more than 3% of river flow annually, Russia in a number of regions is experiencing an acute water shortage, primarily due to the uneven distribution of resources across the territory. The most developed areas of the European part of the country, where up to 80% of the population and production potential are concentrated, account for no more than 10% of water resources. As a result, actively developing cities are taking more and more of their already small water reserves for domestic needs every year. Also, a lot of water is wasted on agriculture
economy and industry (in total more than 65% of all water consumed). In addition, almost all surface and some groundwater bodies, especially in the European part of the country and in areas where large industrial and agricultural complexes are located, are significantly polluted by wastewater and surface water, and this leads to the degradation of water bodies and their ecological systems. It is necessary to raise a literate population and develop in students the skill of rational water consumption in order to avoid serious environmental problems associated with water shortage and pollution in the future.
The goal of the All-Russian eco-lesson “Water of Russia” is to develop a responsible attitude of schoolchildren towards the water resources of Russia and to encourage them to take concrete steps to save water and protect nature in everyday life.
Tasks:
● point out to students the important functions of water in biological systems at different levels;
● introduce them to processes that can disrupt the natural water cycle and cause serious environmental consequences;
● understand the meaning of the concept “water footprint”;
● introduce the types of “water footprint”;
● teach actions that can effectively save water and reduce your water footprint;
● contribute to the formation of a responsible attitude towards water resources among schoolchildren.
When scientists exploring other planets ask whether there is life anywhere else in the solar system, the first thing they look at is water. Without water, life cannot exist. There is a lot of it on Earth, about 70% of the planet’s surface is covered by seas and oceans, but this water is salty. All major terrestrial ecosystems depend on the availability of fresh water containing less than 0.01% salts. There is actually very little such water on Earth. The not-so-good news is that our lives depend on having just 3% water. But there is also a good one - this volume is more than enough for all living beings. Due to the fact that there are so few impurities (salts) in it, organisms can use it internally without fear
pickle from the inside.
Water has a number of physical properties that make it so indispensable in our body, and we need so much of it. According to various sources, an adult is 55-65% water, and a child is 75%. These numbers reflect the total water content of the entire body, but you need to understand that individual organs contain different amounts of water. For example, the brain and spinal cord consists of 80% water, bones 20-33%, cartilage includes up to 60%, and blood is water with blood cells and
other elements and substances dissolved in it, and therefore blood is 92% water; in the muscles there is approximately 60-75% water, and in the kidneys - 82%. But that’s not all: in living plants, water makes up up to 95% by weight, and among animals there are also those that generally consist of almost 99% water - these are jellyfish. Water helps transport substances. If there is not enough water in the body, it begins to “dry out”, vital processes and metabolism are disrupted.
Water is a universal solvent for organic and mineral substances. It dissolves vitamins, amino acids, and also safely removes waste products from the body (including toxins). Water is the most important element of the body's thermoregulation process. When the body is hot, it evaporates water (sweats) and cools down. And when it warms up, the heat enters the blood, which, as you know, contains a lot of water. This water then slowly transfers heat to the entire body, so bodies never immediately cool down if the heat source suddenly disappears.
Water is the main assistant of the human digestive system.
Water is necessary for the normal functioning of the human musculoskeletal system and specifically joints - it is the main lubricant and helps prevent arthritis.
Teacher: Water is a universal carrier of electrons throughout the body, so water is a generator of brain function! If you stay hydrated, your brain will always be active because... its activity is also regulated by water. It’s not for nothing that the brain is 85% water. We have convinced you that fresh water is extremely necessary for all living beings.
There is one natural phenomenon that provides the necessary volume of fresh water on Earth so that plants can absorb it and then, for example, pass it along with food to animals. Or so that there would simply be water in rivers and streams, and living beings could drink it on their own.
This is the water cycle. Water travels across the earth, changing its state of aggregation. As salt water evaporates from the ocean, it ceases to be salty and becomes fresh. In this form, it falls to the ground as precipitation and is absorbed into the soil, ending up in plants or groundwater, or filling fresh water bodies - rivers, lakes, swamps. Numerous travels of water droplets in a circle are constantly taking place. And even the living creatures into which they fall are their temporary shelter. With sweat and other secretions, the water comes out again and goes into
path. It seems to you and me that nothing can affect this cycle. However, in reality today we have a very difficult situation in the world: there is an increasing shortage of fresh water.
In factories, water can be used as a medium for chemical reactions to occur and enable the creation of necessary substances, be part of the product, be used to cool engines, and can be used to remove debris and clean equipment. You can only get water from nature. But the plant not only takes water, it also gives it back, though
it now contains various chemical contaminants, from which it still needs to be cleansed somehow.
People need to eat. To do this, people plant various plants. In order for plants to grow, they need a lot of water to water them. For example, to collect 1 kg of wheat grain, you need 1000 liters of water, and to collect 1 kg of rice, you need to spend 2400 liters of water. Where does it come from?
water for irrigation? Water comes, of course, from nature. Reservoirs are becoming shallow, and what is especially bad is that the water collected is not returned to it. It evaporates from the field directly into the sky or partially seeps into groundwater. 70% of all fresh water withdrawn from the environment by humans is used to irrigate agricultural land. This greatly disrupts the usual cycle and leads to serious consequences. Everyone has heard about the Aral Sea, which no longer exists. The sea disappeared because people began to use water from the Amu Darya and Syr Darya rivers to irrigate their fields. These are two situations of water intake from natural reservoirs. The water is returned either contaminated or not returned at all. This leads to disruption of the natural cycle, deterioration of the condition of living beings and a shortage of much-needed fresh water. All this gives rise to the following three serious environmental problems. First, the spring can only provide a limited amount of water. And immediately related to this is the second one. Downstream ecosystems may suffer as water is diverted in a different direction. It is believed that more than 30% of the average annual river flow cannot be used
flow without the risk of experiencing water shortages on average once every 20 years. The more you take, the more often and sharply the water level will drop. When water is diverted from a river, environmental consequences can affect more than just the river itself. The swamps along many rivers have dried up because they are no longer fed by periodic floods, resulting in the death of huge numbers of aquatic game and other species of plants and animals that lived in these places. The problem also affects estuaries - bays in which fresh river water gradually mixes with sea water. They are among the most productive ecosystems on Earth. These are excellent breeding grounds for many species of fish, shellfish and aquatic birds. When river flows decrease, less fresh water flows into estuaries, their salinity increases and the ecology changes greatly. Thirdly, the water returned to nature is polluted, which is dangerous for both human health and the environment. In order for substances in water to become safe, they must be diluted to the maximum permissible concentration with natural water. But the problem is that sometimes substances get into the water, even a very small amount of which is nevertheless very dangerous for living organisms. In order to estimate how much water people use for their needs and pollute, scientists have come up with a concept called the water footprint. The water footprint includes three different types of water, which we agreed to call conventionally: grey, blue and green. The green water footprint is the amount of rainwater that evaporates or seeps into groundwater during production and crop production. The Blue Water Footprint is the volume of fresh water irrevocably withdrawn from surface or underground sources for use in the production of food and goods, and household life. The gray water footprint is the volume of water required to dilute pollutants discharged during a manufacturing process to a point where water quality meets acceptable standards. Adding these volumes of water together, you and I get a water footprint - the total amount of water that needs to be spent to create something. Let's look at the water footprint of one cup of coffee. It turns out that we
They could drink just one cup of coffee with you, but you had to spend 140 liters of water! This 140 liters includes the water needed to grow the coffee tree, harvest, process, transport and package the coffee beans, sell the coffee, and finally the water used to make the cup of coffee itself. This also includes the volume of water that
was required to dilute to the maximum permissible concentration the amount of pollutants that entered the water as a result of transportation and operation of the enterprise. The water footprint increases even further when milk and sugar are added to coffee. Because they also need to be cooked, and for this you need to raise and feed a cow, grow sugar cane, and all this requires water. If coffee is sold to-go in a disposable cup, the volume of water used to produce the cup will also be added to the coffee's water footprint. And then the water footprint of one cup of coffee will already be 200 liters. We don't suspect it with you, but every object around us was created using water. The process of creating any item can be divided into stages:
resource extraction, material processing, making things (giving shape, color), transportation. When creating a tin can, most of the water will be spent on processing the ore at the metal processing plant and extracting from it the pure metal that is needed to create the can. In this case, the water will become very polluted and will need to be diluted 10,000 times to purify it. When creating a notebook, like any other paper product, you need
a lot of water to soften the wood and create a paper pulp. At this stage, the future paper consists of almost 98% water. When we put on jeans, we don't think about the fact that it was once a plant - cotton. To grow cotton, you need a very large amount of water. Cotton is one of the most expensive crops in the world in terms of the amount of water required. To grow 1 kg of cotton you need 5,263 liters of water. Each person eats, uses things and does so many other things that contribute to the blue, gray or green water footprint and
forms each person's own water footprint. But not only every person has their own water footprint. Every country has it too. Moreover, depending on how the country’s residents live and whether they think about saving water, this footprint will be large or small. Of the national water footprints, China, India, the United States and Russia have the largest: together they account for 38% of global water consumption. This is due to the fact that, in addition to the personal water footprint of the population and agriculture, a lot of industrial enterprises from different parts of the world are also concentrated in these countries. In the world, a lot of water is used to produce things and grow food, but there is another “line of consumption” of fresh water by humans - everyday life.
The question arises as to how people can use water and at the same time reduce their water footprint, otherwise fresh water could soon become a very valuable resource, maybe even more valuable than gold. According to expert estimates, in 1995, 1.8 billion people. lived in areas experiencing severe water stress. By 2025, about two-thirds of the world's population—approximately 5.5 billion people—is expected to live in areas experiencing moderate or
severe water stress. We can try to prevent this if all people around the world change their habits in relation to water and begin to truly save and use it wisely. But it is very important to understand that it is not enough to just turn off the tap and use a cup when brushing your teeth. Our water footprint also consists of products, things, and transport.
Now we know how important it is to use water sparingly.
Over the past decades, improving the efficiency of water use, especially in agricultural production, has been one of the main goals of the international community in solving water problems. The International Natural Resources Institute, the World Water Council, the World Wildlife Fund and other scientific organizations have been using the concept of the water ecological footprint in their research in recent years. This concept has been around since the mid-1990s. developed at the initiative of FAO and UNEP by a group of specialists led by A. Hoekstra at Twenty University, the Netherlands. Ecological water footprint(Water Ecological Footprint), by analogy with the land ecological footprint, represents the share of water withdrawal and accumulation in the process of production of various types of products used by the population 1. Water footprint calculations make it possible to determine the main flows and volumes of withdrawn water and reservoirs of their concentration in manufactured products. The total anthropogenic component of the global water cycle is approximately 22%.
The water footprint consists of the following components.
Blue water trail- the volume of water irrevocably withdrawn from surface or underground sources for household needs and water supply to the population. The bulk of the blue footprint is made up of agricultural water consumption - the use of water for irrigation, as well as for the production of various industrial and household goods (Fig. B10).
Green water footprint- the volume of rainwater falling into the soil and evaporating from the surface of fields, meadows, pastures and forests; this water is involved in the process of transpiration by plants and their creation of biomass (including crops).
Gray water trail- the volume of water required to dilute treated or incompletely treated wastewater generated during the production process. Effluents, which have been treated to varying degrees, must be diluted with clean water in order to comply with agreed sanitary standards.
In addition to these three main categories of aquatic ecological footprint, the concept of virtual water footprint. It denotes the volume of water accumulated in manufactured products and transported through trade or other migration flows between different regions and regions. This is not the physical volume of water intake, but the calculated amount of gross water consumption spent on the production of a certain product and its movement across the territory 1. At international conferences (for example, at the World Water Forum, held in 2015 in South Korea), the idea of taking into account the volume of virtual water in products when concluding trade deals on world markets is expressed and discussed.
Water footprint indicators (both total and its components) are calculated for different periods of time (per year, by season), and in territorial terms - by river basins, countries or continents. The structure of the footprint and its parameters make it possible to judge both the severity of the water management situation in the region and ways to introduce priority and more efficient methods of water use. According to calculations by the International Water Institute (Table 9.3), most of the anthropogenic part of the global water cycle is the green footprint (almost 6,700 km or 74%), i.e. on crop production, transpiration of plants on arable land and grasses on pastures, and evaporation from the soil surface. Water withdrawal is estimated at 11% of the anthropogenic component (blue footprint), and 15% of clean water is required to dilute runoff (gray footprint) (Figure 9.5).
Research has established that in order to maintain the prosperous state of landscape systems, it is necessary that they spend at least 80% of the monthly total flow for their bioproduction needs. If domestic water intake exceeds 20% of the total flow in a particular landscape system, a situation of “water stress” arises in it. In Fig. B11 shows regions of the world with different tensions of the water situation.
Economically developed countries are located mainly in areas of humid climate and have considerable water reserves. However, the rate of increase in water consumption is increasing, and the nature of water use is so irrational that in these regions
Global Water Footprint by Production (1996-2005) 1
Table 9.3
|
Global Water Footprint, million m3/year |
Agricultural production |
Industrial production |
Household water supply |
Total |
||
|
crops on arable land |
pastures |
water supply livestock farms |
||||
|
Water footprint in export products, million m3/year | ||||||
|
Water footprint in export products, % of total volume | ||||||
1 Based on: Mekonnen M. M., Hoekstra A. Y. The green, blue and gray water footprint of crops and derived crop products.
Rice. 9.5.
1 - green trace; 2 - blue trace; 3 - gray trace
serious water problems arose. Of these, the main one is a sharp deterioration in the quality of surface water sources as a result of the discharge of insufficiently treated wastewater, acid precipitation and the infiltration of various pollutants from soil and ground. Surveys show that the volume of gray water in these countries remains very significant (see Figure 9.5). Noteworthy is the fact that huge volumes of water (virtual water) accumulate in various production products - in agricultural goods (food), industrial and household goods, which are concentrated in a limited area in the process of local production and consumption or through export-import flows of produced goods. goods move across land around the globe. This complicates the calculation of production withdrawals of water masses (gross water consumption) and their subsequent anthropogenic migrations (volumes of virtual water). However, such calculations give an idea of the real tension of the water management situation in regions of the world (Fig. 9.6).
They are trying to fill the deficit of high-quality fresh water in different ways. In a number of land areas (Saudi Arabia, the US Great Plains, Iran, etc.) there are significant groundwater resources that are intensively pumped. So, only in the river basin. The Yellow River annually produces 30 km 3 of water from underground horizons, and up to 12 km 3 from the Ogalalla artesian basin in the USA. Aquifers are severely depleted, and groundwater pumping is accompanied by ground subsidence and a decrease in river levels in drainage basins.
Another way to solve the water management problem is desalination of salty sea or lake waters. In the 2000s. The scale of desalination of such waters in the world has reached 1 15 km 3 . Since the technology of desalination of salt water is a very expensive and energy-intensive undertaking, it is still used on a small scale, in limited areas of land, where the issue of obtaining clean drinking water is especially acute: in the Middle East, northern Africa, the USA and other areas.
An increase in water reserves is achieved in a number of regions of the world by transferring runoff from one river basin to another.
Rice. 9.6.
Water trail is the total volume of fresh water used to produce goods and services. The water footprint is measured by the volume of water used or polluted per unit of time and includes not only direct, but also indirect use of water resources. The concept of a water footprint was developed in 2002 by specialists from the Dutch University of Twente Erien Hoekstra and Mesfin Mekonnen and is a further development of the concept of virtual water.
Distinguish between production and consumption water footprints . Industrial water footprint takes into account direct and indirect costs of water resources necessary for the production of goods and provision of services. Consumer water footprint takes into account the total water footprint of all goods and services consumed. Consumer water footprint territories, in turn, are divided into interior, taking into account the use of own water resources, and external, taking into account the use of water resources by the party providing goods or services, imported virtual water.
The water footprint can be calculated for an individual or a group of people, a specific product or service, an enterprise or an entire economic sector, an administrative unit, a territory or an entire state.
There are also three gradations of the water footprint:
Russia's industrial water footprint is about 400 billion m 3 /year (4.4% of the world), and its consumer water footprint is about 270.5 billion m 3 /year (3.2% of the world), of which 12.4% is external water footprint The average water footprint of one resident of Russia is about 1.85 thousand m 3 /year per person. For comparison: domestic water consumption per capita in Russia is about 58 m 3 /year per person, which is only 0.3% of the water footprint!
In 2014, the International Standards Organization published the ISO 14046:2014 standard “Environmental management. Water trail. Principles”, containing recommendations for measuring water footprints for companies and government organizations. Calculating the water footprint allows you to assess the potential risks of using water resources, identify the most effective ways to reduce the environmental impact of water consumption, and increase the efficiency of economic activity.
Popular science encyclopedia “Water of Russia”
March 20 2015 DetailsEach of us has our own “water footprint” - the amount of clean water we use daily for our needs. At the same time, water is also necessary for the production of a wide variety of goods and things that we use or eat. Water consumption in a home or office is easier to track thanks to meters and monthly bills that we have to pay. Often when we talk about water consumption, we're talking about how long we shower, how often we run the dishwasher, or how long it's been since we've had a leaky faucet fixed.
But it’s even more important not to forget about the “water footprint” our consumption of certain products and goods leaves, since it may turn out to be much larger than you think. Below we give just a few examples of how much water is required to produce a particular product (based on materials from www.greenword.ru):
Tea
30 liters of water for 1 cup of tea, 250 ml
From 1 kg of fresh tea leaves, the production of which takes 2600 liters of water, 260 g of tea leaves are obtained. A cup of tea contains 3 g of this brew.
Orange
50 liters of water for 1 orange, 100 g
Growing 1 kg of oranges requires 500 liters of water. Water consumption for 1 glass of orange juice (200 ml) is about 170 liters.
Apple
140 liters of water per apple, 250 g
Growing 1 kg of apples takes about 700 liters of water (depending on the variety). The cost for a glass of apple juice (200 ml) is about 190 liters.
Egg
200 liters of water per chicken egg, 60 g
On average, producing a ton of eggs requires about 3,300 m3 of water. Most of it goes to feed the chickens (see below).
Coffee
280 l of water per coffee pot, 250 ml
1 kg of roasted coffee beans requires 21,000 liters of water; a coffee pot requires 14 g of coffee, i.e. Each drop of drink is 11,000 drops of water.
Corn
450 liters of water per ear of corn, 500 g
Growing maize around the world annually requires 550 billion m3 of water - 8% of total water costs for growing crops
Wheat
1000 liters of water per 1 kg of wheat
Growing wheat around the world annually requires 790 billion m3 of water - 12% of total water costs when growing crops.
Milk
1000 liters of water per 1 liter of milk
It takes about 200 liters of water to produce 1 glass of milk (200 ml). 1 glass of drinking water uses only a little more water than is poured into it.
Chick
1170 l of water per 300 g fillet
The chicken is raised for 10 weeks, and 1.8 kg of meat is obtained from the carcass. During his life, he eats 33 kg of grains, drinks 20 liters of water, and another 10 liters are spent on keeping him clean. Total water costs - 7000 l.
Goat meat
1200 l of water for 1 steak, 300 g
The goat is raised for 2 years, and the carcass produces 20 kg of meat. During her life, she eats 55 kg of grain and 165 kg of roughage, drinks 2 m3 of water, and another 1.5 m3 is spent on keeping it clean. Total water costs - 80,000 l.
Pork
1440 l of water for 1 steak, 300 g
The pig is raised for 10 months, and the carcass produces 90 kg of meat. During her life, she eats 385 kg of grain, drinks 7 m3 of water, and another 4 m3 is spent on keeping it clean. Total water costs - 435,000 l.
Cheese
2500 l of water per 0.5 kg
To produce 0.5 kg of cheese, 5 liters of milk are needed, that is, 5000 liters of water (see above). The process also produces about 3.6 liters of whey, which is comparable in cost to the resulting cheese. Thus, the water consumption of 5000 liters can be divided into two.
Rice
3400 l of water per 1 kg
Growing 1 kg of wild rice requires an average of 2,400 liters of water; further industrial processing requires another 1,100 liters. Rice fields around the world use about 1,350 billion m3 of water per year - 21% of the total water consumption when growing crops.
Beef
4500 liters of water for 1 steak
The cow is raised for 3 years before slaughter, and the carcass yields about 200 kg of boneless meat. During her life, she eats 1300 kg of grain and 7200 kg of roughage, drinks 24 m3 of water, and another 7 m3 is spent on keeping it clean. Total water costs - 3 million 1500 liters of water.
Professor Arjen Hoekstra, one of the creators of the “water footprint” concept, notes: “Many countries, by importing goods whose production requires huge amounts of water, shift their “water footprint” onto others. In regions that export such goods, the pressure on water resources is growing, and they often do not have an effective water management system and modern water-saving equipment.”
It is clear that we will not be able to give up all goods or products at once, but everyone can limit their choice and become a more responsible consumer. Reduce your meat consumption or become a vegetarian, avoid buying extra cotton T-shirts and drink less coffee. Don't forget that more than 2.7 billion people have problems with access to clean water at least one month a year. And millions of people survive with minimal amounts of water every day. Water is a priceless gift that we must protect and preserve for the sake of our future and the future of life on Earth.
Timur Idrisov, Environmental organization “Little Earth”
Based on materials from: Treehugger and www.greenword.ru
The total amount of fresh water used for production and domestic consumption - water footprint - The term was coined in 2002 by Dutch professor Arjen Hoekstra, and since then data has been collected from different countries in order to know about all water footprints.
Human-generated water footprints affect water stress—in 50 countries around the world, populations currently suffer from a lack of fresh water. In these places, the demand for water is greater than the amount of water available. By 2025, two-thirds of the world's population is expected to live in water-stressed areas.
We use more water in our daily activities than we realize. Water is used for food (drinking and washing), in production and technological processes.
There are three types of water trail:
The average annual global water footprint is 1,240 cubic meters per capita. To get an idea of the amount of water that countries consume, we have the example of Spain, with an annual consumption of 2325 m3 of water per person, or the USA, where each person uses 2500 m3 of water per year.
1. 16,000 liters of water are needed to obtain 1 kg of meat and 700 liters for 10 apples. 3000 liters of water are needed for 1 kg of rice.
2. Lack of drinking water causes the death of 4,500 children every day in developing countries.
3. The Aral Sea dried up due to cotton production. The impact of cotton crops in Uzbekistan is terrible: intensive irrigation has led to the drying up of the Aral Sea. Interestingly, the cotton is then exported. It is estimated that the EU is indirectly responsible for 20% of the drying up of the Aral Sea.
4. About 1800 million people suffer from water shortages. 50 countries currently suffer from severe water shortages, but this number could increase as a result of climate change.
5. Grains, meat and milk need water the most.
6. The faucet drips - losses up to 75 liters per day.
7. China, India and the USA are the countries that use the most water (38% of the total).
According to Arjen Hoekstra, “many countries significantly export their water footprint by importing water-intensive goods from elsewhere. This puts pressure on water resources in export regions, where mechanisms for wise management and conservation of water resources are too often lacking.”
- Be economical when you take a shower, wash dishes, turn on the washing machine, flush the toilet, water the garden plants. .
