Water resources of the earth. Types of water resources

The meaning of water. Use of water resources

Chemically pure water does not occur in nature. The composition of water usually includes at least 18 substances, including dissolved gases and salts, suspended solid and liquid substances that determine its taste, smell, color and other properties.

Of all liquids, water serves as the best solvent and has the highest heat capacity. Living organisms cannot do without water. It is part of the cells and tissues of all animals (75% of their total mass) and plants (about 90% of their total mass). The most complex reactions in plant and animal organisms can only occur in an aquatic environment. The human digestion process requires 9-10 liters of water per day. Loss of 10-20% of water by an animal leads to death. The role of water in plant photosynthesis is especially important. In the biomass of Earth's organisms, the volume of water reaches 1.1 thousand km 3 .

World water consumption is trending upward. The needs of the planet's population consume 7-8 km 3 of water per day. Natural waters are used in economic activities in the following areas: drinking water supply, food industry, domestic water supply, recreation, tourism, sports, livestock needs, pond fish farming, rain-fed and irrigated agriculture, industrial and thermal power water supply, hydropower, shipping.

Water use is divided into water use And water consumption. The water user does not take water from a natural source (river, reservoir), but only uses it for various purposes without changing the quantity. These are, first of all, hydropower, shipping, timber rafting, fisheries, and recreation. A water consumer, taking water from a source, returns it to a river or reservoir, usually in smaller quantities and of a different quality (water supply).

All types of economic activities can be divided into 2 groups:

activities carried out directly on water bodies(creation of ponds and reservoirs, construction of dams, flow transfer, etc.);

activities within the catchment(cutting down and planting forests, draining swamps, plowing land, using fertilizers, draining stormwater from industrial sites, urban areas, settlements, etc.).

The economic activities of the first group have a greater influence on the quantitative characteristics of water resources, and the second - on the qualitative ones.

In terms of water availability, Belarus is in relatively favorable conditions. Own resources are quite sufficient to meet water needs. The structure of total water intake is dominated by groundwater, whose share currently amounts to about 65%. In Belarus, the total water intake from natural sources (underground and surface) increased until 1991, and in the last 14-15 years there has been a steady decline, which can partly be explained by the rational use of natural resources, their payment, as well as restructuring in the country’s production sector after the collapse of the USSR.

The main water consumers in the country are housing and communal services and industry (75% of total water consumption). Large-scale industry and thermal power engineering are provided primarily by river waters, and the public utility needs of the population and the needs of food and light industry enterprises are provided by groundwater (more than 30 thousand artesian wells are operated).

Even though about 70% of the earth's surface is covered with water, it is still a very valuable resource. Especially when it comes to quality. What are water resources? What is their structure and world reserves? What are the most pressing water problems of our time? All this will be discussed in the article.

What are water resources?

Geographic, as is known, consists of five spheres: litho-, atmospheric-, bio-, techno- and hydrosphere. What are water resources? This is all the water that is contained in the hydrosphere. It is found in oceans and seas, lakes and rivers, glaciers and reservoirs, in the soil and in the air (in the form of water vapor).

About 70% of the earth's surface is covered with water. Only 2.5% of this volume is fresh water, which humanity needs. In absolute terms, this is no less than 30 million cubic kilometers, which is thousands of times greater than the needs of world civilization. However, we should not forget that the bulk of these reserves are contained in the “ice shells” of Antarctica, the Arctic and Greenland. In addition, the state of water resources available to humans is often unsatisfactory.

Structure of planetary water resources

The planet's water resources are divided into two classes:

• waters of the World Ocean;
• terrestrial (or surface) waters.

Rivers, lakes, reservoirs and glaciers hold only four percent of the world's waters. Moreover, most of them (by volume) are confined specifically to glaciers. And the largest “reservoir” of fresh water on the planet is Antarctica. Underground flows are also classified as water resources of the Earth, but their quantitative estimates vary greatly in numbers.

Pure is the most valuable for humans and any other living organisms. Its protection and rational use is one of the most important tasks of mankind at the present stage.

Water resource update

Features of water resources are the possibility of self-purification and renewal. However, the renewability of water depends on several factors, in particular the type of hydrological body.

For example, water in rivers is completely renewed in about two weeks, in a swamp - in five years, and in a lake - in 15-17 years. This process takes the longest time in ice sheets (on average it takes 10 thousand years), and the fastest in the biosphere. In a living organism, water goes through a full renewal cycle in a few hours.

Distribution of water resources by macroregion and country

The Asian region leads the world in terms of total water resources. It is followed by South America, North America and Europe. The poorest corner of the planet in terms of water reserves is Australia.

However, there is one important nuance here. So, if you calculate the volume of water reserves per capita of a continent or part of the world, you get a completely different picture. With this calculation, Australia comes out on top, but Asia comes in last. The thing is that in Asia the population is growing at a rapid pace. Today it has already reached the milestone of four billion people.

Which countries don't have to worry about water? Below are the top five states with the largest fresh water reserves. This:

1. Brazil (6950 km 3).
2. Russia (4500 km 3).
3. Canada (2900 km 3).
4. China (2800 km 3).
5. Indonesia (2530 km 3).

It is worth noting the uneven distribution of water resources on Earth. Thus, in the equatorial and temperate climate zones they are even found in abundance. But in the so-called “arid” (tropical and subtropical climate) the population experiences an acute shortage of life-giving moisture.

Water resources and people

Water is in demand in everyday life, energy, industry, and recreation. The use of this resource may be accompanied by its extraction from a natural source (for example, from a river bed) or without it (for example, for the operation of water transport).

The largest consumers of water resources are:

• Agriculture;
• industrial and energy enterprises;
• communal sphere.

The volumes of municipal water consumption are constantly growing. According to environmentalists, in large cities of economically developed countries, one person uses at least 300 liters of liquid daily. This level of consumption may lead to a shortage of this resource in the near future.

Pollution and depletion of world waters

Pollution of water resources is very acute. Today it has reached catastrophic levels in some regions of the planet.

Every year, millions of tons of chemicals, oil and petroleum products, phosphorus compounds, and municipal solid waste enter the World Ocean. The latter form huge ones out of garbage. The waters of the Persian Gulf, North and Caribbean seas are very polluted with oil. Already about 3% of the surface of the North Atlantic is covered with an oil film, which has a detrimental effect on living organisms of the ocean.

A big problem is also the reduction of the planet's water resources. However, the deterioration of the quality of life-giving moisture is no less dangerous. After all, one cubic meter of untreated sewage can fall into the natural riverbed and spoil tens of cubic meters of clean water.

In the developing countries of the world, according to statistics, every third inhabitant suffers from poor-quality drinking water. It is the main cause of many diseases in the population of the "arid belt" of Africa and Latin America.

Main types and sources of pollution of world waters

In ecology, water pollution is understood as the excess of the maximum permissible concentrations of substances contained in them (harmful chemical compounds). There is also such a thing as the depletion of water resources - the deterioration of water quality under constant activity.

There are three main types of water pollution:

• chemical;
• biological;
• thermal;
• radiation.

Any substance that enters a hydrological object as a result of human activity can act as a pollutant. At the same time, this substance significantly worsens the natural quality of water. One of the most dangerous modern pollutants is oil, as well as products from it.

Sources of pollution can be permanent, periodic or seasonal. They can be of both anthropogenic and natural origin, be point, linear or areal.

The largest source of pollution are the so-called That is, those that are formed as a result of industrial, construction or municipal human activities. They are usually oversaturated with harmful organic and inorganic substances, heavy metals and microorganisms. There are industrial (including mine), municipal, agricultural and other types of wastewater.

Characteristics of water resources in Russia

Russia is one of the countries in the world that does not experience water shortages. The modern water resources of the country are 2.5 million rivers and streams, about two million lakes and hundreds of thousands of swamps. The territory of Russia is washed by twelve seas. A huge amount of fresh water is stored in glaciers (mountain and polar).

To improve water supply, thousands of reservoirs of various sizes have been created on the territory of our state. In total, they contain about 800 km 3 of fresh water. These objects not only serve as artificial reservoirs of a valuable natural resource, but also regulate the regime of rivers and prevent floods and floods. Thus, their importance cannot be overestimated.

Among the main problems of water resources in Russia, the following should be highlighted:

• irrational water use;
• deterioration in the quality of drinking water;
• unsatisfactory condition of waterworks and hydraulic structures.

Finally...

What are water resources? This is all the water that is contained in the hydrosphere. Countries such as Brazil, Russia, Canada, China, Indonesia and the USA have the largest reserves of water resources.

In modern realities, the problem of pollution and irrational use of world waters is becoming very urgent, and in some regions - especially acute. Its solution is impossible without consolidating the efforts of all countries on the planet and effectively implementing joint global projects.

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

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

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

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

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

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

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

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

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

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

Sources of replenishment of drinking water.open reservoirs - rivers, lakes, springs. To obtain drinking water from these sources, additional purification is required.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

5. Comment on whether water is an inexhaustible resource.

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

7. Describe the water cycle in nature.

Water is one of the irreplaceable sources of existence of any living creature on Earth. With the development of new technologies, the need for it is growing every day.

Water resources of the Earth: general characteristics

The world's water resources (hydrosphere) are the totality of all possible sources of water on planet Earth. It is no secret that any sphere of life requires water components. Statistics show that the volume of the hydrosphere is quite large - 1.3 billion km. However, this figure does not reflect the sufficiency of water in the world, since fresh drinking water plays a strategic role, and its amount ranges from 2 to 2.6%.

The world's water resources (fresh) include ice blocks in Antarctica and the Arctic, natural lakes and mountain rivers. However, it is unfortunately impossible to gain full access to these sources.

Problems of world water resources

At the moment, only a few countries in the world are sufficiently supplied with water, and according to statistical data, about 89 countries generally suffer from water deficiency. The role of water is difficult to overestimate, and its poor quality is the cause of 31% of diseases on Earth. The problems of the world's water resources should not be ignored by any state in the world, but should be resolved promptly and collectively.

Every year the demand for water increases, this is directly related to population growth and economic development. Many states are now introducing new methods for obtaining water, purifying it, and enriching it with minerals. Unfortunately, water accumulates very slowly, and therefore belongs to the group of non-renewable resources.

World water use

Water resources on planet Earth are distributed extremely unevenly. If the equatorial regions (Brazil, Peru, Indonesia) and the northern temperate zones are provided with water above the norm, then all tropical regions (accounting for 63% of the total area of ​​the globe) experience an acute shortage of water.

Global water use is generally stable. The largest percentage of water comes from agriculture and heavy industry (metallurgy, oil refining, automotive, chemical and woodworking industries). Modern thermal power plants are no less competitive with these sources of use. Despite their cheapness, obtaining energy by this method not only significantly reduces the amount of target water, but also pollutes and makes water in nearby bodies of water unsuitable for consumption.

The World Water Council was founded in 1996 with the support of 50 countries and 300 international organizations. This is a universal international platform whose main goal is to solve global water problems. To attract the attention of the international community, the Council periodically holds the World Water Forum. Once every three years (May 22), members of this organization nominate competent specialists and professors who propose new methods for solving present and future problems, demonstrate existing indicators and other information about water resources.

The world's water resources come from a variety of sources: mountains, oceans, rivers, glaciers. The vast majority of them offer low quality water due to natural and anthropogenic factors:

• drainage of used (polluted) waters into rivers and seas;
• use of fresh water for domestic needs (washing cars in reservoirs);
• entry of petroleum products and chemicals into water bodies;
• imperfect water purification system;
• inaction of environmental protection authorities;
• lack of financial resources.

Only 4% of the world's water resources are polluted from natural sources. This is usually the release of aluminum from the earth's crust.

Contaminated water is a source of infectious diseases

Clean fresh water resources of the countries of the world currently exist in nature in practically inaccessible sources (glaciers, mountain lakes), and therefore people more often resort to purifying simple river water. However, if it is poorly processed, then the risk of getting an infectious disease is extremely high. Dirty water is a source of severe, intractable diseases, such as typhus, tuberculosis, cholera, dysentery, glanders, etc. During the 18th and 19th centuries, most terrible pandemics began with the consumption of dirty water.

The statistics on this issue are quite disappointing, since about half of humanity suffers from bad water. Residents of Africa and Central Asia not only do not have access to fresh water, but also do not have the ability to purify the available water.

World Water Day

World Water Day was introduced by the UN in 1993 and is celebrated annually on May 22. In honor of this day, the UN Secretary-General holds various forums, meetings, round tables, and meetings on global water problems. Also on May 22, UN statistics show new data on the increase or decrease in the level of water resources in various countries of the world (geography of world water resources).

Each year, a new topic is chosen that is of most concern to international consumers. These include questions about the amount of water in modern water basins, water diseases, water natural disasters, water resource shortages, fresh water sources, and water supply problems in cities.

Ways to overcome deficit

The characteristics of the world's water resources show that this resource is non-renewable, therefore most civilized countries of the world are trying to use water rationally in various ways. Ways to overcome water deficit include:

1. Installation of meters that will correctly and accurately calculate the amount of water used.

2. Creation of a strong information base, dissemination of information about water shortages in society through the media, journalism, etc.

3. Improvement of the sewer system.

4. Savings. Simple rules for saving water by the population can help significantly reduce its consumption for more useful purposes.

5. Creation of reservoirs for fresh water.

6. Introduction of sanctions for violation of water legislation.

7. Desalination of salt water or detoxification of dirty water with chemicals. If previously aggressive chemicals were used to destroy microbes, now, as a rule, harmless compounds of iodine or chlorine are common.

Water resources play a significant role in the life of modern society. Its quality, quantity, physical condition, temperature and other characteristics directly affect the life activity of all living things on planet Earth. However, modern society has abandoned this valuable resource, and therefore the urgent issue is the creation of an effective mechanism for the purification and rational use of water.

Water resources consist of many sources, but they all make up the hydrosphere. Its unsatisfactory condition can lead to the extinction of people, animal populations, the disappearance of plants, and the spread of infectious diseases.

The problem of water in the world is urgent and requires prompt intervention. If the international community ignores such issues, then there is a threat of a complete shortage of water resources on 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.

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 global hydrological cycle.

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. It may
become a major factor hindering economic development and population growth.

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 contamination, 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 characteristics of water associated with excessive enrichment with nutrients.

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.