Concept and meaning of water resources
The world's water resources are all the waters of the hydrosphere, including the waters of the world's oceans, surface and underground waters of the continents. These are integral and extremely valuable natural resources of the planet. Water is the most abundant substance on our planet: although in varying quantities, it is available everywhere, and plays a vital role for the environment and living organisms. Fresh water is of greatest importance, without which human existence is impossible, and nothing can replace it. Humans have always consumed fresh water and used it for a variety of purposes, including domestic, agricultural, industrial and recreational use.
Interesting facts about water
Glaciers contain much more water than many people think. So, if they all melted instantly, the sea level would rise by 8 meters, and 13% of the land would be flooded.
It is commonly believed that water freezes at zero temperature, but this is not entirely true. Salt water in the seas, for example, freezes only at -2 °C (or lower). And sometimes it freezes even at above-zero temperatures.
Water is found on many planets of the solar system, on their satellites, and also in comets. True, all this water is presented in the form of ice, or water vapor. But finding it in a liquid state is quite a difficult task.
It is believed that one of Jupiter's satellites (Europe) contains huge reserves of liquid water. Perhaps there are even living organisms there.
Water reserves on Earth
Water exists in three states of aggregation: liquid, solid and gaseous. It forms oceans, seas, lakes, rivers and groundwater located in the upper layer of the Earth's crust and soil cover. In its solid state, it exists in the form of snow and ice in polar and mountainous regions. A certain amount of water is contained in the air in the form of water vapor. Huge volumes of water are found in various minerals in the earth's crust.
Determining the exact amount of water reserves around the world is quite difficult because water is dynamic and in constant motion, changing its state from liquid to solid to gaseous and vice versa. As a rule, the total amount of water resources in the world is estimated as the totality of all waters in the hydrosphere. This is all the free water that exists in all three states of aggregation in the atmosphere, on the Earth's surface and in the earth's crust to a depth of 2000 meters.
Current estimates have shown that our planet contains a huge amount of water - about 1386,000,000 cubic kilometers (1.386 billion km³). However, 97.5% of this volume is salt water and only 2.5% is fresh. Most of the fresh water (68.7%) is found in the form of ice and permanent snow cover in the Antarctic, Arctic, and mountainous regions. Further, 29.9% exists as groundwater, and only 0.26% of the Earth's total fresh water is concentrated in lakes, reservoirs and river systems where it is most easily available for our economic needs.
These figures were calculated over a long period of time, but if shorter periods are taken into account (one year, several seasons or months), the amount of water in the hydrosphere may change. This is due to the exchange of water between the oceans, land and atmosphere. This exchange is usually called the water cycle in nature, or the global hydrological cycle.
Water wealth
| Water resources of our planet | |
| are of natural origin | created artificially |
| ocean | pond |
| sea | channel |
| river | reservoir |
| lake | |
Parts of the river
Source - the beginning of the river
A channel is a depression through which a river flows.
Estuary - a place where a river flows into another river, lake or sea
Tributary - small rivers that flow into the main river.
On the mountain tops, snow and glaciers begin to melt with the arrival of spring. At this time, the temperature rises significantly. This creates water streams that flow down the slopes. A little lower, small streams join together. Having united, small streams gain strength and flow faster, carrying particles of earth and rock fragments with them. A mountain stream appears. Having reached a valley, that is, a more level area, and then a gentle plain, the flow slows down. It turns into a river.
Freshwater resources
Fresh water contains a minimal amount of salts (no more than 0.1%) and is suitable for human needs. However, not all resources are available to people, and even those that are are not always suitable for use. Consider sources of fresh water:
- Glaciers and snow covers cover about 1/10 of the world's land mass and contain about 70% of fresh water. Unfortunately, most of these resources are located far from populated areas and are therefore difficult to access.
- Groundwater is by far the most common and accessible source of fresh water.
- Freshwater lakes are mainly located at high altitudes. Canada contains about 50% of the world's freshwater lakes. Many lakes, especially those in dry areas, become salty due to evaporation. The Caspian Sea, Dead Sea, and Great Salt Lake are among the world's largest salt lakes.
- Rivers form a hydrological mosaic. There are 263 international river basins on Earth, which cover more than 45% of the planet's landmass (with the exception of Antarctica).
Water resources objects
The main objects of water resources are:
- oceans and seas;
- lakes, ponds and reservoirs;
- swamps;
- rivers, canals and streams;
- soil moisture;
- groundwater (soil, groundwater, interstratal, artesian, mineral);
- ice caps and glaciers;
- precipitation (rain, snow, dew, hail, etc.).
Problems of water use
For many hundreds of years, human impact on water resources was insignificant and of an exclusively local nature. The excellent properties of water - its renewal due to the cycle and the ability to be purified - make fresh water relatively purified and possessing quantitative and qualitative characteristics that will remain unchanged for a long time.
However, these features of water gave rise to the illusion of the immutability and inexhaustibility of these resources. Out of these prejudices arose a tradition of careless use of extremely important water resources.
The situation has changed greatly over the past decades. In many parts of the world, the results of long-term and mismanagement of such a valuable resource have been discovered. This applies to both direct and indirect water use.
Around the world, over the course of 25-30 years, there has been a massive anthropogenic change in the hydrological cycle of rivers and lakes, affecting water quality and their potential as a natural resource.
The volume of water resources, their spatial and temporal distribution, are determined not only by natural climate fluctuations, as before, but now also by the types of economic activities of people. Many parts of the world's water resources are becoming so depleted and heavily polluted that they can no longer meet ever-increasing demands. This can be a major factor hindering economic development and population growth.
Lesson “Water resources of Russia. Water protection" lesson plan in geography (8th grade) on the topic
Geography lesson in 8th grade
Lesson topic: “Water resources. Water protection."
A person does not value water until the source dries up.
(Mongolian proverb)
Lesson Objectives
Educational:
- formation of students’ knowledge about water resources and their importance;
-give an idea of the distribution of water resources across the territory of Russia;
-give an idea of the water cadastre, natural phenomena associated with water;
-develop the ability to extract necessary information from various sources.
Educational:
- formation of the ability to independently work with the atlas;
- formation of skills to extract the necessary information and draw conclusions;
- formation of skills to analyze the information received;
— development of information culture of students;
-developing the ability to listen and engage in dialogue.
Educational:
-developing the ability to participate in a collective discussion of a problem;
-continuation of environmental education of schoolchildren;
-instilling a careful and economical attitude towards water resources;
- instilling in students concern for the environment and their health;
-development of a sense of beauty.
Teaching methods:
explanatory - illustrative, problem - searching, heuristic.
Equipment:
computer presentation, physical map of Russia, lesson plan, atlases, textbook edited by E.M. Domogatskikh N.I. Alekseevsky. Geography. M., “Russian Word”, notebooks.
Lesson type:
combined
Topic study plan (on the board):
- Meaning of water
- Assessment of water resources and their distribution throughout the country
- Water cadastre
- Use of water resources
- Human influence on water quality
- Water protection
- Natural natural phenomena associated with water
Epigraph of the lesson on the board: “A person does not value water until the source dries up” (Mongolian proverb).
During the classes.
1. Organizational moment.
Hello. Sit down. Check if everything is ready for the lesson.
2.Homework survey.
Test survey (3 people at a computer. Time to complete the task - 6 minutes)
Oral response at the board.
Additional questions about the physical map of Russia are asked by class students.
Summing up the survey results, grading
3. Explanation of new material.
Setting goals and objectives for the lesson.
Once people argued about what could be considered wealth: one suggested that it was money and gold, another called love and human relationships wealth, the third argued that wealth is what Mother Nature gives us: water, air, Earth. They argued for a long time. What do you guys think, which one is right? (Students make their own assumptions).
Yes, each of you is right in your own way. But still we cannot do without nature at all. Man cannot live without air and water. We will continue to study the topic “Inland Waters” and today we will talk about Russia’s water resources and their protection.
Children formulate the topic of the lesson and write it down in a notebook (slide 1).
The teacher asks students to formulate the objectives of the lesson based on the proposed lesson plan.
Preparing students to perceive new material.
Today you will learn about the importance of water, try to assess water resources and their distribution on the territory of Russia, get acquainted with the concept of “water cadastre”, consider measures to protect water, remember natural natural phenomena associated with water. Your classmates will be my assistants today.
Explaining new material by the teacher with the help of students
Student message (see appendix to lesson notes).
Tells about the meaning of water….
We are encouraged to conserve water resources. What are water resources? (students try to define it themselves). Let's compare your definition and what is given in the textbook on p. 123. Copy it in your notebook.
Let's consider the diagram “Natural waters and people” (textbook p. 123). What mutual influence does “man on water” and “water on man” have? What conclusion can we draw from this diagram?
Activation of mental activity.
Open the physical map of Russia in the atlas.
What types of water resources are shown on the map of Russia? (discussion of student answers).
What water resources are not shown on the map, but we use them all the time? (The groundwater)
Where are the most large rivers? (In Siberia) What is this connected with? (climate and terrain)
What conclusion can we draw? Is Russia well supplied with water resources?
Conclusion: our country is rich in water resources.
Posing a problematic question to students.
Do you think a country rich in surface water can suffer from a lack of fresh water and why? (Not all water is safe to drink)
Now we will find out how fresh water is used. Consider the diagram on p. 124 of the textbook.
Explaining new material using ICT.
The main consumer of water resources is industry. It consumes on average about 22% of all water intake. With a well-developed industry, this figure can increase to 56%. Water consumption in the production of cast iron, chemical fibers, and cellulose sometimes amounts to hundreds of cubic meters of water. To produce 1 ice cream, 5 liters of water are required, to produce fabric for one shirt - 15 liters of water, and to produce 1 kg of sugar - 100 liters of water. Human water consumption exceeds the consumption of other natural resources hundreds of times. Increased consumption causes depletion of these resources. And although our planet is 70% covered with water and water resources, fortunately, are renewable, you should understand that you need to take care of water resources and remember that they are still limited.
Working with terminology.
A full assessment of water resources is given in the Water Cadastre (slide). Water Cadastre is a systematic collection of information about water resources (slide). It summarizes the materials of long-term observations of water resources and evaluates them.
Write the definition in your notebook.
Explaining new material by the teacher with the help of students
How much water we spend at home will be told by ……………(slides).
Explaining new material based on previously acquired knowledge.
The source of water resources is river flow, and its main value is that it is renewable. In terms of river flow reserves, Russia ranks 2nd in the world after Brazil. Remember the name of the most abundant river in the world, flowing in Brazil. (Amazon). Its river flow is 2 times greater than the river flow of all Russian rivers combined. However, in terms of the volume of water flow per person, Russia is in 4th place, and in terms of 1 sq. km - only 9th. (Russia slide map)
Water reserves in lakes and swamps are of certain importance. On the territory of our country there is the largest source of fresh water, which contains 19% of the world's fresh water reserves - Lake Baikal. (slide). Let's consider some problems associated with the use of water resources in our country. These problems are associated not so much with water shortages, but with the characteristics of hydrosphere objects and the peculiarities of economic management within Russia. (slide map of Russia with water cadastre)
Explaining new material using an interactive map
Firstly, Russia is characterized by an uneven distribution of water resources. Most (2/3) of water resources are concentrated in the basins of the Arctic and Pacific oceans, where 1/5 of the country's population lives and the basins of the largest rivers are located: Ob, Yenisei, Lena, Amur. At the same time, the main part of the country’s economic potential is concentrated in the basins of the Black, Caspian and Azov seas. These areas account for less than 10% of the country's river flow. But more than 80% of Russia’s population lives here, and it is here that the shortage of water resources clearly manifests itself.
Secondly, annual and seasonal fluctuations in the flow of rivers in our country are significant. For example, in high-water years, the flow of many rivers can exceed the norm by 1.5-2 times. And in low-water years it becomes the same amount lower. Seasonal fluctuations in flow are even more significant. For example, under natural conditions, before the construction of reservoirs, the Volga and Don rivers accounted for 60-70% of the annual flow during the spring flood period, and 10% during the winter low water period. Seasonal fluctuations in river flow complicate the operation of transport, the operation of power plants, and water intake for industrial and household needs. Reservoirs are built to regulate river flow.
Thirdly, using large amounts of water leads to water loss. The use of water by humans on an industrial scale leads to a decrease in the river flow of the Volga by 10%, and of the Don, Kuban and Terek - from 25 to 40%. The flow of small rivers, for example, such as the rivers of our region, has decreased by more than 50%. Every year, about 80 cubic meters are withdrawn from all sources in Russia. m. water. This is approximately the same amount as the annual flow of the Yana, Indigirka, and Neva rivers. After using the water, 60 cubic meters are returned. m. of water, and 20 cubic meters. m. is lost.
Fourthly, high pollution of the water surface.
Working with a video fragment covering regional environmental problems.
There are many environmental problems related to water sources in the Plavsky region. Look at the story that was shown on Tula television less than a year ago.
(video) State Television and Radio Broadcasting Company TULA Death of fish in the Plava River.mp4 Discussion of the video fragment.
-Let’s imagine an extreme situation: the water will disappear or will be unsuitable for human use. Where it leads?
Expected answers from students (every living thing will disappear).
-What needs to be done to prevent such a situation?
Suggested student responses (preserve, save, cleanse, etc.)
One of the methods of preserving water is its purification.
— In addition to water purification, a number of measures must be observed to protect clean water.
Developing the ability to participate in a collective discussion of a problem and finding ways to solve it
What measures can you suggest to protect water from pollution? Now look at the screen (slide).
Currently, the problem with the construction of treatment facilities at the Plavsky distillery has been practically solved, but we will feel the consequences of unreasonable human behavior for a long time.
Using students' practical experience
There is a legend that the saint in whose honor the Plavskaya Church is named, Sergius of Radonezh, founded his monastery far from the water. He wanted to perform this difficult duty, carrying water, for the glory of God. But when the monastery grew and people from all over Russia began to flock, it became difficult for the monks to carry water. They complained. Sergius entered the dense forest, struck the Earth with his staff, and a spring began to flow out of it, giving rise to a river.
Unfortunately, in our country, most people still live in accordance with the words of the proverb, which I took as the epigraph to our lesson (the proverb is read out).
But is water always good? Look at the screen, what unites the concepts indicated on the screen? (flood, mudslides, ice, ice, rain, drought). All these are natural phenomena associated with water. Every year people suffer from them.
Now watch a short video about the flood (while watching the video, the teacher accompanies the image with text).
Text to accompany the video fragment:
Flooding on a river is a terrible phenomenon. Usually calm rivers swell and become powerful water streams. The water rushes with monstrous force: swift, treacherous, terrible, with whirlpools, bubbling, roaring, destroying everything in its path. It crushes bridges, washes away roads, houses, overturns cars, trains, washes out roads, and paralyzes life in a limited area. People tolerate everything. On the rivers of our country, floods occur frequently and are sometimes catastrophic. The following cities suffer from Volga floods: Tver, Nizhny Novgorod, Kazan, Samara, Astrakhan. In April of this year, the Tula region was hit by the strongest flood in the last few years. The water level in the river immediately rose by 5 meters. Due to rains and sudden melting of snow, several streets of Tula and its suburbs were flooded. 14 bridges were under water. 46 settlements were left without direct transport links. Residents were transported by boat, food, goods and even pensions were delivered to them by water. On northern rivers, flooding is caused by ice jams formed during ice drift. (The teacher’s story is accompanied by a display of photographic material)
Using interdisciplinary connections when explaining new material
Guys, what do you think, can a person predict a flood now? How to avoid loss of life? You will learn how to behave in emergency situations in a life safety lesson. Remember the major floods that have occurred recently and their consequences. (Summer flood in the Kuban - the cities of Krymsk and Novorossiysk were heavily damaged; in 2012, there were also floods in Slovenia, Great Britain, Spain, and Venice)
4. Fastening
Working with a crossword puzzle on the topic “Water resources of Russia.”
A crossword puzzle will help you figure out what you remember well and what you need to pay attention to. The crossword puzzle time is 3 minutes.
Now check yourself with the answers indicated on the screen.
Raise your hand for those who gave less than 10 correct answers. From 10 to 15, from 15 to 20? Are there anyone who managed to answer all the crossword questions?
5. Lesson summary
I would like to end the lesson with one instructive legend that will remind us of the difference between true, eternal values and imaginary, passing values.
On the island of Sri Lanka in the 5th century AD. King Dhatusen reigned. His state was captured by rebels who demanded that the king show them hiding places with royal treasures. The king led his enemies to the artificial lake he had created. This lake saved the lives of the island's inhabitants during a drought. The king scooped up a handful of water and said: “My friends, this is my wealth.” Let's take care of the wealth given to us by nature - water!
So, we have considered all the questions planned for the lesson. What new did you learn today? Is water wealth?
Our lesson has come to an end. Today we received grades in class. For the oral answer at the board………, for working with tests…………, for messages…………..
6.Reflection
There is a questionnaire on your desk. It will help me find out your opinion about today's lesson. To do this, answer the questions
-Were there any moments of the lesson that particularly interested you? (Not really)
-Is knowledge of documents on environmental legislation important? (Not really)
-What questions on the topic are you still interested in?
-Did the pace of the lesson seem comfortable to you?
7. Homework assignment paragraph 22. Practical part: find out from your parents how much cold and hot water costs, are there water meters installed in the apartment? How much does it cost to pay for water? Do you have any questions for me about homework?
Additional material for the lesson “Water resources. Water protection."
Each of us knows that without water there is no life. An adult consists of 60% water, and a child is 80%. Every cell in the body needs water. The most water is found in the brain - 80% and in the blood - 90%. Water is the medium where digestion processes take place. Water flushes waste metabolic products from the body and removes them from the body. With a loss of water in the amount of 6% of body weight, a person’s temperature rises, with a loss of 10%, the swallowing reflex is impaired, hallucinations begin, and with a loss of 12% of fluid, a person dies.
The human body needs constant replenishment of water supplies. For normal life, each person needs to consume approximately 2.5 liters of water per day. This can be done by not only drinking water, but also eating. The most water is found in mushrooms, vegetables and fruits. It is also recommended to drink juices and fruit drinks made from vegetables and fruits.
Water is the most important, most important substance in the world around us. About 70% of the Earth's surface is covered by the World Ocean. But most of the water is salty, and there is only about 5 million kW of fresh water suitable for life. km or 2.8%. Every year, people need more and more fresh, clean water. Some countries are already experiencing shortages of clean fresh water and are forced to import it from abroad. Therefore, the water resources of our country must be protected!
Recently, the rate of water pollution with various wastes has increased. The most important water problem is the pollution of water sources with industrial, domestic and wastewater. A danger to water bodies is runoff from fields, where environmentally hazardous technologies are often used. Gross violations in the use of mineral and organic fertilizers are allowed. Stagnant zones often arise and pollution accumulates in wastewater discharge areas. As a result, fish die, the species composition changes, and their numbers decrease. Water pollution causes poisoning of livestock, damage to gardens and vegetable gardens. Such waters are not suitable for drinking. In addition, transportation impacts water quality. They clog the waters with household waste, garbage, drain oil, waste fuel. All these factors exceed the ability of water to self-purify.
To purify water, it is passed through screens and sent to a settling tank, where it is filtered. A layer of sand and gravel serves as a cleaning filter. Chlorination is used to disinfect drinking water. The chlorination method is also used in our region for water purification, although it is outdated and environmentally unsafe for health. Chlorination of water primarily affects the digestive organs, liver, and kidneys.
It is calculated that 1 cu. m of untreated wastewater entering a natural water body can pollute hundreds of cubic meters of clean water, thereby creating unacceptable conditions for the life of aquatic organisms (organisms living in water). Therefore, technologies that either do not use water at all or do not produce polluted wastewater are promising. Their successful implementation into practice would completely solve the problem of protecting water bodies from pollution. Currently, a number of chemical industries have switched from water cooling of high-temperature gas mixtures to air cooling.
Water supply technologies that are characterized by minimal consumption of fresh water are also promising. With closed technology, an enterprise takes water from a natural source, uses it to produce products, after which the resulting wastewater undergoes deep purification and is returned to the cycle.
At the end of the 19th century, one and a half buckets a day were enough for a city dweller - both for washing and even for extinguishing a fire. The current norm is over 18 buckets, i.e. 220 l. In fact, we do not meet this standard either, spending 30-40 buckets of water per person.
A gentle stream of water fills a 12-liter bucket in a minute. You stood in the shower for 5 minutes - 60 liters of water ran down the drain. This would be more than enough to carefully wash an elephant.
A match-thick stream fills a liter jar in 3 minutes. This experiment allows us to establish that at least 500 liters of water leak out of a faulty tap per day.
There is an opinion that industry wastes most of the water. In fact, industry takes only a quarter of the water supplied to the city every day. The same amount goes to canteens, kindergartens, and hospitals. The rest goes to residential buildings.
But saving water without any hygienic damage is not at all difficult. For example, after brushing, you can rinse your teeth from a glass by closing the tap. Saving 5 liters. For one person – cleaning. While shaving, instead of opening a tap with hot water, you can pour water from a kettle into a glass, as in the old days; shaving will take not 5-10 liters, but only 200 ml, and there are millions of people shaving...
Housewives believe that they should rinse clothes after washing in running water. Of course, this way the laundry is rinsed faster, but the water consumption is high. Modern detergents are washed out of clean laundry even after it has been left in standing water for 10-15 minutes. By the way, in washing machines, clothes are also rinsed in 2-3 waters, but not in running water.
It is better to wash dishes in a sink with two compartments and drain plugs. You can also wash vegetables.
In our country, state control over the use of water resources is carried out by the Ministry of Natural Resources. The main task of the Ministry is state control over compliance with the requirements of water legislation, standards, and rules. State inspectors are vested with broad powers: they have the right to visit facilities and organizations that are water users and consumers, give instructions to eliminate identified violations of the regime for using water bodies and monitor their implementation, inspect and detain vessels that have allowed the illegal release of pollutants, and impose administrative penalties against persons guilty of violating water legislation. Decisions of state control bodies are binding on all water users and can only be appealed in court.
Water pollution
The main causes of water pollution are:
Wastewater
Domestic, industrial and agricultural wastewater pollutes many rivers and lakes.
Disposal of waste in seas and oceans
Burying garbage in the seas and oceans can cause huge problems, because it negatively affects living organisms that live in the waters.
Industry
Industry is a huge source of water pollution, producing substances harmful to people and the environment.
Radioactive substances
Radioactive pollution, in which there is a high concentration of radiation in the water, is the most dangerous pollution and can spread into ocean waters.
Oil spill
An oil spill poses a threat not only to water resources, but also to human settlements located near a contaminated source, as well as to all biological resources for whom water is a habitat or a vital necessity.
Leaks of oil and petroleum products from underground storage facilities
Large quantities of oil and petroleum products are stored in tanks made of steel, which corrode over time, causing harmful substances to leak into the surrounding soil and groundwater.
Precipitation
Precipitation, such as acid precipitation, occurs when air is polluted and changes the acidity of water.
Global warming
Rising water temperatures cause the death of many living organisms and destroy a large number of habitats.
Eutrophication
Eutrophication is a process of reducing the quality of water associated with excessive enrichment of nutrients.
Reservoirs
Reservoirs are not just additional “reservoirs” of water resources, but also play important functions:
- flood control;
- flood control;
- creating the necessary conditions for recreation and irrigation (necessary to ensure the population and agriculture);
- ensuring the operation of hydroelectric power plants (producing more than 1600 billion kWh of electricity).
The largest number of reservoirs and, as a result, hydroelectric power stations are located in the Eastern regions of the country.
Reservoirs and their operation can lead to unfavorable ecological conditions in the region. Deformation of river banks can be observed, landslides occur, and emergency situations are possible due to the poor general condition of waterworks. That is why the work of reservoirs and hydroelectric power stations is closely monitored by special services.
Water resources are not unlimited, although they are renewable. In general, the Russian Federation uses 87.3 km3 of water per year (with total strategic reserves of 97 thousand km3 per year), including 71.0 km3 from surface sources, 11.9 km3 from underground sources and 4.3 km3 of sea water . Every resident of the country uses about 1 m3 of water per year (at the rate of 2.5 -3 liters per day). Also, for each resident of the Russian Federation per year there is an average of 30 thousand m3 of total river flow, 530 m3 of total water intake and 90-95 m3 of domestic water supply (i.e. 250 liters per day).
The protection of water resources is the responsibility of the state, but environmental education of the population also plays an important role in their preservation. Scientists have proven that in Russia, unlike other countries in the world, fresh water is used extremely uneconomically.
Rational use and protection of water resources
Water resources require rational use and protection, ranging from individuals to enterprises and states. There are many ways we can reduce our impact on the aquatic environment. Here are some of them:
Saving water
Factors such as climate change, population growth and increasing aridity are increasing pressure on our water resources. The best way to conserve water is to reduce consumption and avoid increased wastewater.
At the household level, there are many ways to save water, such as taking shorter showers, installing water-saving appliances, and washing machines with low water consumption. Another approach is to plant gardens that do not require much water.
