Water pollution and protection of the hydrosphere. Topic: Geography of the world's natural resources
Introduction
3. Fresh water problems
3.1 Freshwater resources
Conclusion
Introduction
Water reserves on Earth are enormous; they form the hydrosphere - one of the powerful spheres of our planet. The hydrosphere, lithosphere, atmosphere and biosphere are interconnected, penetrate one another and are in constant, close interaction. All spheres contain water. Water resources are composed of static (secular) reserves and renewable resources. The hydrosphere unites the World Ocean, seas, rivers and lakes, swamps, ponds, reservoirs, polar and mountain glaciers, groundwater, soil moisture and atmospheric vapor.
Water is one of the most important life-supporting natural environments formed as a result of the evolution of the Earth. It is an integral part of the biosphere and has a number of anomalous properties that affect the physical, chemical and biological processes occurring in ecosystems.
1. Hydrosphere and its protection from pollution
Pollution - visible or invisible, on land, air or water - is now an unwelcome but familiar part of our lives. Pollution can be described as the introduction by mankind of substances or materials that degrade the quality of environment. These substances (pollutants) are introduced into the environment by humans and not as a result of natural oil seeps or volcanic eruptions, which can be called natural pollutants. Many pollutants are synthetic substances that are foreign and therefore dangerous to us and other organisms.
The human impact on the living resources of the biosphere, including the World Ocean, in our time is not limited only to the removal of bioproducts, cultivation and changes in the composition and size of populations. Over the past decades, the influence of industrialization and urbanization has been growing and expanding especially rapidly. modern society, intensification and chemicalization Agriculture and other attributes of scientific and technological progress that are associated with pollution of the biosphere and the emergence of new environmental factors. A special place in this complex and multifaceted problem is occupied by the issues of pollution of the World Ocean. Many, if not most, of the toxic substances released from human control on land ultimately end up in marine environment, creating a situation of local, regional or global pollution of the seas and oceans.
Recently, pollution of the seas and the World Ocean as a whole (background pollution) has caused great concern. Global (background) pollution of the hydrosphere is determined mainly by the atmospheric transport and removal of pollutants from the atmosphere. With the exception of crude oil, all pollutants enter the world's oceans largely through the atmosphere. Every year, more than 109 tons of solid, vapor and gaseous compounds are burned and released into the atmosphere. In atmospheric aerosols and ocean deposits, products such as DDT, polychlorinated biphenyls, mercury, lead, and ash were found in noticeable quantities.
The main sources of pollution are domestic and industrial wastewater (60% of large cities are concentrated in coastal areas), oil and oil products, and radioactive substances. Pollution from oil and radioactive substances is especially dangerous. Enterprises in coastal cities throw thousands of tons of various, usually untreated, waste into the sea, including sewage. Polluted river waters are carried into the seas. Oil and petroleum products enter the water as a result of washing tanks and containers in which oil is transported. A huge amount of oil ends up in the ocean and seas during accidents of tankers, oil pipelines in oil fields, and during the exploration and exploitation of oil fields in the continental shelf zone. When oil wells fail, many thousands of tons of oil are released into the sea.
Pollution causes the death of marine animals, crustaceans and fish, waterfowl, and seals. There are known cases of death of about 30 thousand sea ducks, mass death starfish in the early 1990s in the White Sea. There are frequent cases of beach closures due to dangerous concentrations of pollutants in sea water.
Unfortunately, it is practically impossible to preserve the integrity and pristine state of natural waters on a large scale at the current pace of social development and scientific and technological progress, since human activities deeply affect all parts of the biosphere, including the hydrosphere.
1.1 Measures to protect the waters of the seas and the oceans
Measures to protect the waters of the seas and the World Ocean consist of eliminating the causes of deterioration in water quality and pollution. Special measures to prevent seawater pollution should be taken during the exploration and development of oil and gas fields on continental shelves. It is necessary to introduce a ban on the disposal of toxic substances in the ocean and maintain a moratorium on testing nuclear weapons under the water. Rapid action should be taken to eliminate the consequences of accidents and disasters that release toxic products into the ocean. The problem of protecting the waters of the World Ocean is global; it concerns all states of the planet. To protect the waters of the World Ocean, joint efforts of all states of the world community, the UN and its divisions are necessary. To a large extent, such measures can be successful with the participation of states in international environmental programs that are developed and proposed by relevant conventions and provided for by international agreements.
1.2 Protection of water resources from pollution and depletion
The scale of pollution and depletion of water resources has now become alarming. The problem of shortage of fresh water has become acute in densely populated areas, large industrial centers, and in areas of irrigated agriculture. Lack of clean drinking water and pollution of water bodies are the cause of many human diseases and have a detrimental effect on animals and flora Earth. In many places, fresh water pollution is moving from local to regional.
The protection of water resources as an integral part of the protection of the natural environment is a set of measures (technological, biotechnical, economic, administrative, legal, international, educational, etc.) aimed at the rational use of resources, their conservation, prevention of depletion, restoration of natural relationships , balance between human activity and the environment.
Principles of water protection.
Important principles of water protection are:
prevention - preventing the negative consequences of possible depletion and pollution of water;
comprehensiveness of water protection measures - specific water protection measures should be an integral part of the overall environmental program;
ubiquity and territorial differentiation;
focus on specific conditions, sources and causes of pollution;
scientific validity and availability of effective control over the effectiveness of water protection measures.
The most important technological measures for the protection of water resources are the improvement of production technologies and the introduction of waste-free technologies. The recycling water supply system is currently being used and improved, or reuse water.
Since it is impossible to completely avoid water pollution, biotechnical measures for the protection of water resources are used - wastewater treatment from pollution. The main cleaning methods are mechanical, chemical and biological.
During mechanical wastewater treatment, insoluble impurities are removed using grates, sieves, grease traps, oil traps, etc. Heavy particles settle in settling tanks. Mechanical cleaning It is possible to free water from insoluble impurities by 60-95%.
During chemical treatment, reagents are used that convert soluble substances into insoluble ones, bind them, precipitate them and remove them from wastewater, which is purified by another 25-95%.
Biological treatment is carried out in two ways. The first - in natural conditions - on specially prepared filtration (irrigation) fields with equipped maps, main and distribution canals. Purification occurs naturally by filtering water through the soil. The organic filtrate is subjected to bacterial decomposition, exposure to oxygen, sunlight and is subsequently used as fertilizer. A cascade of settling ponds is also used, in which self-purification of water occurs naturally. Second - accelerated method wastewater purification - produced in special biofilters through porous materials of gravel, crushed stone, sand and expanded clay, the surface of which is covered with a film of microorganisms. The process of wastewater treatment on biofilters occurs more intensively than on filtration fields. Currently, almost no city can do without treatment facilities, and all these methods are used in combination. This gives a good effect.
In many countries, the problem of protecting water from pollution began to be addressed at the government level, and large funds were allocated to solve it. However, some industrial countries have approached establishing order in their inland waters in a very unique way. They, on the one hand, developed measures to prevent or eliminate pollution, investing large amounts of money in this, and on the other hand, they began to transfer enterprises that most heavily pollute water bodies to developing countries. This helped improve the situation in the most industrialized countries, but did not solve the problem on the planet as a whole, since catastrophic pollution of rivers and reservoirs began in developing countries, and pollution of the World Ocean continued.
2. Features of pollution of the World Ocean and surface waters
Sources of pollution of the World Ocean are many objects of human economic activity. Main pollutants: industrial and municipal waste, oil and petroleum products, vehicle emissions, agricultural and livestock waste, including pesticides and mineral fertilizers, radioactive substances.
The main types of pollution are: physical (identified by smell, color); chemical (increased mineralization - the presence of chlorides, sulfates, nitrates, heavy metal ions, dissolved hydrogen sulfide and other gases); organic (hydrocarbons - oil and petroleum products, phenol); biological (Escherichia coli, bacteria and other microorganisms); radioactive, thermal, mechanical (turbidity, presence of immiscible liquids). It should be taken into account that many substances accumulate in organisms; their concentration increases in animals located at the tops of trophic pyramids.
Pollutants can be divided into mineral and organic or, more logically, into: organic non-toxic, mineral and organic toxic (including radioactive), mixed.
2.1 Organic and mineral contamination
Organic non-toxic pollutants include fecal waste, timber rafting waste, cellulose fibers in discharges from paper mills and some others. They can cause the death of aquatic organisms through deterioration of the oxygen regime, the formation of hydrogen sulfide, or due to mechanical impact.
Of the mineral substances discharged into water, cyanide, arsenic, lead and copper compounds are especially toxic to hydrobionts. Some acids and alkalis, the lethal concentrations of which are usually expressed in grams per liter, are noticeably less harmful to hydrobionts. Of the toxic organic pollutants discharged into water bodies, the most harmful to aquatic organisms are synthetic detergents, phenol, creosol and naphthenic acids, the lethal doses of which are 10-100 mg/l. Petronic acids are especially dangerous, since oil and its products containing them enter the water in huge quantities. During the cleaning of tankers and ships whose engines run on oil alone, more than 3 million m3 of oil products are discharged into the water annually.
The most widespread pollutants of surface and, in some cases, groundwater are mercury and lead. In Sweden, many of the freshwater and marine fish contain mercury in the range of 200-1000 ng/kg. An increased content of mercury was noted in the formed elements and blood plasma and hair of people who ate fish. Mercury has been found in the meat of eagles, pheasants and other animals. An increase in mercury along the links of the food chain has been established. Rivers annually carry about 5,000 tons of mercury and its compounds into the oceans, of which, for example, methylmercury has a higher toxicity and intensely glows in the tissues of hydrobions. The average concentration of mercury in seawater today is 0.03 µg/l, and bottom sediments are even more enriched in mercury.
Lead also plays an important role in water pollution. Rain alone removes 250,000 tons of lead from the atmosphere annually over the ocean and 100,000 tons over land. 150,000 tons of lead come from soils annually. In this regard, over 45 years, the lead content in sea water has increased from 0.01-0.02 to 0.07 mg/kg.
Other metals, such as zinc, nickel, cadmium, and chromium, also enter water bodies in significant quantities. With their participation, the active centers of a number of enzymes are neutralized and some proteins are destructured. Arise cardiovascular diseases.
Radioactive isotopes, or radionuclides, are of great importance in the pollution of water bodies. Radiation from radionuclides is capable of moving electrons from one atom to another, as a result of which each of them acquires a charge. The magnitude of contamination of water bodies with radionuclides can be judged by the fact that the United States alone dumped several tens of thousands of curies of waste into the Pacific and Atlantic oceans from 1946 to 1963. Radioactive contamination of water bodies also occurs as a result of the deposition of radionuclides from the atmosphere. The surface of the water is 1.5-2 times more effective collector of radioactive aerosols than land.
2.2 Organic liquids and gases, carcinogenic substances
In addition to the well-known groups of global toxicants (oil and petroleum products, heavy metals, organochlorine compounds), two more types of substances should be mentioned, the release of which into the environment has become very widespread - organic liquids and gases (dichroethane, freons, solvents) and carcinogenic substances, having blastomogenic properties (polycyclic aromatic hydrocarbons such as benzopyrene).
We must also not forget about the processes of eutrophication associated with the removal of organic substances, fertilizers, detergents and other compounds of phosphorus and nitrogen into coastal waters, leading to the intensive development of phytoplankton and some types of bottom algae and secondary pollution of the sea with the products of their metabolism and decay.
In the last decade, along with eutrophication, pollution of both surface and groundwater has increased significantly as a result of the ingress of toxic components that are alien to aquatic ecosystems and deeply disrupt their normal functioning. The danger of pollution is associated not only with the direct negative effect of toxicants on the functioning of aquatic organisms, but also with the fact that in the aquatic environment toxic components are transformed, form complexes of metallographic and inorganic compounds, and are converted into other substances, often more toxic than the original ones. For example, metals in the form of ions in some cases turn out to be less toxic to aquatic organisms than their organometallic compounds containing methyl, ethyl or phenyl radicals. Similar changes in the aquatic environment occur with polyphenols, which turn into quinones, which are more toxic than the original compounds.
Oil and petroleum products play an equally important role in the pollution of continental water bodies and the World Ocean. The amount of oil entering the World Ocean is estimated at 5-10 million tons per year.
Significant factors of pollution of natural water bodies include pesticides (chlorinated hydrocarbons, including the DDT group, organic phosphates, arsenic-containing preparations and carbamates) entering water bodies with surface and subsurface runoff, as well as wastewater.
It is impossible not to mention household waste, which, along with the eutrophication effect, can also cause pollution of natural waters. Thus, in the USA, 15 kg are dumped into the sewer every year. solid waste per person.
Consequently, despite the gigantic volumes of water masses on our planet, man has become one of the essential links in the formation of their qualitative and often quantitative indicators.
3. Fresh water problems
The problem of provision fresh water Currently, it is one of the most pressing issues, since water shortage in some cases becomes a limiting factor in the process of technical progress and the future of humanity largely depends on its solution.
Heavy use water reserves surface and underground sources in industrial, domestic and drinking water supply, their pollution, eutrophication, warming lead to a reduction in available globe relatively small resources of clean fresh water (3% of all terrestrial moisture), a sharp deterioration in its quality and an increase in water deficit. With the current scale of anthropogenic influence on the biosphere, the quality of natural waters is formed not only as a result of the functioning of natural ecosystems, but also due to the production activities of society, and the human influence on the hydrosphere is multifaceted, significant and often negative.
As a result, today more than 200 million people in the world are completely deprived of clean drinking water.
The total water reserve on the globe is over 1370 million km3 and is composed mainly of the water of the World Ocean. The volume of fresh water is only 32.2 million km3, including glaciers (25 million km3), groundwater and groundwater (3,720 thousand km3), soil moisture (90 thousand km3), lakes (120 thousand km3) , rivers (12 thousand km3) and atmospheric vapor (14 thousand km3).
3.1 Freshwater resources
The existing reserves of water resources and a number of ambitious technical solutions to water problems make it possible today to ensure global water supply in almost the required volume while simultaneously discharging 450 km3 of wastewater into rivers and lakes, for dilution of which more than 5500 km3 of clean river water is needed, that is, 1/7 world reserves.
Fresh waters make up an insignificant (about 2% of the hydrosphere) share of the total water reserves in nature. Fresh water available for use is found in rivers, lakes and groundwater. Its share of the entire hydrosphere is 0.3%. Fresh water resources are distributed extremely unevenly; often the abundance of water does not coincide with areas of increased economic activity. In this regard, the problem of lack of fresh water arises. It is aggravated by the ever-increasing volumes of its use. Current water consumption is national economy quantitatively exceeds the total use of all other natural resources, since production in major industries consumes huge amounts of fresh water. Thus, to process 1 ton of oil it is necessary to spend about 60 tons of water, to produce 1 ton of conventional fabric products - 1100 tons, synthetic fiber - up to 5000 tons of water. To grow and obtain 1 ton of wheat grain, 2 tons are spent, and rice - over 25 tons of water. Water turns into the most precious raw material, which cannot be replaced. The reserves and availability of water resources dictate the location of new industries, and the problem of water supply is becoming one of the most important in the life and development of human society.
3.2 Causes of lack of fresh water
The problem of fresh water shortage arises for several reasons, the main of which are: uneven distribution of water in time and space, the increase in its consumption by humanity, water losses during transportation and use, deterioration of water quality and its pollution. Anthropogenic causes of freshwater depletion and pollution include the following: withdrawal of surface and groundwater; spillway from mines, adits; development of deposits - solid minerals, oil and gas, industrial waters, sulfur smelting; urbanization - residential development, energy facilities (nuclear power plants, thermal power plants). Fresh waters are heavily polluted by industrial enterprises: chemical, food, pulp and paper, ferrous and non-ferrous metallurgy, oil refining, construction materials, engineering. Pollution enters water bodies during the construction of pits, tunnels, subways, hydraulic structures, and during drainage work. Water is polluted by transport, water, heat, gas communications, sewerage, and power lines. The most important water pollutant is agricultural production: farming, land reclamation, livestock farming. The danger of fresh water pollution is associated with the storage of raw materials, household, industrial and radioactive waste, mineral fertilizers, pesticides, and petroleum products. Pollution occurs when gases and liquids are pumped into the subsurface and oil deposits are flooded. Disposal of highly toxic waste. Grandiose projects for the transformation of nature do not take into account the possible pollution of fresh water: river flow diversion, land reclamation, shelterbelts. Freshwater pollution is associated with military exercises, testing and disposal of nuclear, chemical and other types of weapons.
The growth in fresh water consumption by the population on the planet is determined by 0.6-2% per year. IN beginning of XXI century, the total water intake is expected to be 12-24 thousand km3. Water consumption increases due to increasing prosperity, as can be seen in the following example. Water consumption by one urban resident in the southern regions of Russia is: in a house without sewerage 75, in a house with sewerage 120, with a gas water heater 210 and with all amenities 275 l/day. For a city in central Russia, the water consumption rate according to the “Household and Drinking Consumption Standards for Settlements” (SNiP-II.31 - 74) is: in houses without bathtubs 125-160, with bathtubs and heaters 160-230 and with central hot water water supply 250-350 l/day.
Fresh water losses increase with the growth of per capita consumption and are associated with the use of water for household needs. Most often this is due to imperfect technology in industrial, agricultural production and public services. Water losses from water-carrying communications in Russian cities amount to 30-35%. In cities of regional significance, water losses amount to approximately 10-15 million tons per year and double every 5 years. Large losses of fresh water occur during the development of mineral deposits and during construction drainage of urban areas. Water losses are largely due to lack of knowledge natural conditions(geological-lithological and hydrogeolithological, climatic and meteorological, biological properties), internal patterns and mechanisms of ecosystem development. When creating reservoirs, the increase in filtration on their sides and the increase in evaporation with an increase in the water surface are not always taken into account. The creation of a cascade of ponds on rivers damages river flow. Drainage of swamps leads to a decrease in groundwater reserves, disrupts the established moisture balance and circulation for centuries, changes the species composition of biocenoses, etc. The construction and use of canals contributes to severe soil salinization, waterlogging and huge losses of fresh water.
In some cases, the lack of fresh water is associated with the unpredictability of the negative consequences of human activity. Thus, the construction of canals (Volga-Chogray, Volga-Ural), cascades of reservoirs, irrigation and watering of pastures, drainage of swamps, etc. did not lead to the expected positive effects; on the contrary, these projects resulted in the loss and pollution of water resources.
The deterioration of water quality is associated with the ingress of human activity products directly into water from rivers and other surface water bodies, groundwater, and through the atmosphere and soil. The deterioration of freshwater quality is the most dangerous and becomes threatening to human health and the spread of life on Earth. Its extreme condition is catastrophic water pollution.
Deterioration of water quality and pollution, depletion of water resources occurs constantly. This is due to contact with water and the transfer of various substances. Changes are cyclical, less often spontaneous: they are associated with volcanic eruptions, earthquakes, tsunamis, floods and other catastrophic phenomena. Under anthropogenic conditions, such changes in the state of water are unidirectional: foreign substances that enter the water accumulate in it, worsening its organoleptic properties. Water pollution occurs when the amount of foreign substances contained in water, especially those that have an adverse effect on humans, animals and plants, reaches critical levels.
Conclusion
What can we expect in the near future for the World Ocean, for most important seas?
In general, pollution of the World Ocean is expected to increase by 1.5-3 times over the next 20-25 years. Accordingly, the environmental situation will worsen. Concentrations of many toxic substances can reach a threshold level, followed by degradation of the natural ecosystem. It is expected that the primary biological production of the ocean may decrease in some large areas by 20-30% compared to the current level.
The path that will allow people to avoid an environmental dead end is now clear. These are waste-free and low-waste technologies, turning waste into useful resources. But it will take decades to bring the idea to life.
Future biological resources The world's oceans are under serious threat and require effective measures to protect them from pollution. The world's oceans should be an arena international cooperation in the field of rational use and protection of its resources, involving participation in international programs all states interested in preserving the World Ocean as the most important ecosystem of the world.
List of used literature
1. Goldberg V.M. The relationship between groundwater pollution and the natural environment. - L.: Gidrometeoizdat, 1987. - 248 p.
2. Elkin A.V. Water pollution and problems of their protection // elkin52. narod.ru
3. Konstantinov A.S. General hydrobiology. M.: Higher School, 1967. - 432 p.
4. Konstantinov V.M. Nature conservation: Textbook. Allowance for students. Higher Ped. Proc. Institutions. - M.: Academy, 2000. - 240 p.
5. Kostin S.N. Problems of environmental pollution // www.ecosystema.ru
6. Patin S.A. chemical pollution and its influence on aquatic organisms // Biology of the Ocean. T.2. Biological productivity of the ocean / ed. M.E. Vinogradova. - M.: Nauka, 1977. - P.322-331.
7. Sirenko L.A., Gavrilenko M.Ya. “Blooming” of water and eutrophication. - Kyiv: Naukova Dumka, 1978. - 232 p.
Water resources.
Water, occupying 71% of the Earth's surface, is the most abundant and valuable resource. The world's water reserves are enormous - about 1389 million km 3 . If they were distributed equally, then there would be 280 billion liters for each inhabitant of the planet. However, 97% of water resources come from oceans and seas where the water is too salty. The remaining 3% is fresh water. They are distributed as follows:
Water makes up between 50-97% of the weight of all plants and animals and about 70% of the weight of the human body.
Of all fresh water, humanity can use only 0.003%, because... it is either heavily contaminated or lies at great depths and cannot be removed by reasonable prices, or contained in icebergs, polar ice, in the atmosphere and in the soil.
Water is in a constant cycle, Fig. 1. This natural process recycling occurs until water consumption becomes more intensive than its reserves are replenished and until the volume of waste is exceeded, making the water unusable. There are two sources of fresh water: surface water and groundwater.
Rice. 1. The water cycle in the biosphere.
Surface water is fresh water flowing from a certain area into streams, lakes, swamps and reservoirs. The area from which surface water, which may carry sediment and pollutants, flows into the main river and its tributaries is called a spillway, or drainage basin. But only part of the annual flow can be used.
Some of the runoff flows at such a speed that it is impossible to retain it, while the other part must be left in the rivers to maintain life in them. In dry years, the total volume of runoff is significantly reduced.
Groundwater. Part of the atmospheric precipitation seeps into the ground and accumulates there in the form of soil water, filling the pores of the soil and soil. Ultimately, most of the soil moisture evaporates and returns to the atmosphere.
Under the influence of gravity, some of the water moves deeper and fills pores and cracks in layers of sand, gravel and sandstone. The zone in which all pores are filled with water is called the saturation zone. Permeable, water-saturated sediments are called aquifers, and the water contained in them is called groundwater. If the rate at which water is withdrawn from an aquifer exceeds the rate at which it is stored, groundwater will go from being a slowly renewable resource to a non-renewable resource within a human lifetime.
Groundwater can be non-pressure and pressure. Unconfined groundwater is found above a layer of impermeable rock or clay. To collect free-flow groundwater, boreholes and wells are used and the water is extracted by pumps.
Pressurized groundwater forms between two impermeable layers (for example, clay) and is under excess pressure. When opening wells, water can spontaneously flow to the surface. Such wells are called artesian wells. In other wells the pressure is lower and the water must be pumped out.
Use of water. The criteria for water use are indicators of water intake and water consumption. Almost three-quarters of the water produced in the world is used for irrigation, the rest of the water is used in industry and public utilities, for cooling equipment in power plants, etc.
Growing one ton of wheat requires 1,500 tons of water, one ton of rice requires more than 7,000 tons, and one ton of cotton requires 10,000 tons.
Huge amounts of water are required for food production and various industrial products. Before it appears in the store liter jar canned fruits or vegetables, it will use 40 liters of water. To produce the daily norm of food per person, about 6 m 3 of water is required.
Water problems
Water shortage. The problem of providing the population with a sufficient amount of fresh water is relevant for many areas of the world. Every year about 25 million people suffer from drought, of which about 20 thousand die. Severe droughts, leading to famine and disease, periodically occur in 80 countries, most of them in Asia and Africa, which are home to 40% of the world's population. Almost 150 out of 214 largest rivers world are used by two or more countries. In these states, disputes and conflicts arise over the use of water.
Excess water. Excess rainfall leads to floods. In India, for example, 90% of precipitation falls from June to September. In the 1980s, about 15 million people were affected by severe floods. About 5,000 people died annually, and property damage amounted to tens of billions of dollars. Floods and droughts are considered natural disasters. However, since the 1960s, human activity has been responsible for the sharp increase in the number of deaths caused by floods. The destruction of vegetation and soils that retain moisture, the construction of roads and other structures contribute to the rapid drainage of rainwater.
Contaminated drinking water. In 1983 World organization Health (WHO) estimates that 61% of the rural and 26% of the urban population of developing countries, i.e. 1.5 billion people use dirty water. Every year, about 5 million people die from cholera, dysentery and other water-borne diseases (an average of 13,700 people per day).
Main sources of water pollution. Of the total volume of withdrawn water, only 1/4 is used irrevocably, 3/4 of the water is returned with wastewater. Even after treatment, wastewater must be diluted clean water. Worldwide, 5,500 km 3 of clean water is spent on wastewater disposal, i.e. 30% of the planet's runoff. The main sources of water pollution are shown in Fig. 2
Pollution can be divided into several groups. By physical condition– insoluble, colloidal and soluble. Composition: mineral, organic, bacterial and biological.
Minerals are represented by sand, clay, mineral salts, solutions of acids, alkalis, etc.
Organic - can be of plant or animal origin, and also contain oil and products derived from it, synthetic surfactants (surfactants).
Bacterial and biological pollution - wastewater from food and light industry enterprises, household wastewater (runoff from toilets, kitchens, showers, laundries, canteens, etc.). At many industrial enterprises, water is used as a coolant, solvent, is included in products, and is used for washing, enrichment, and purification of raw materials and products.
In addition, in many technological processes synthetic surfactants (surfactants) are used. It is currently one of the most common chemical pollutants and is difficult to control. Surfactants can have a negative impact on water quality, the self-purifying ability of water bodies, the human body, and also enhance the adverse effects of other substances.
An important source of pollution are pesticides that enter water bodies with rain and melt water from the soil surface. During aerial cultivation of fields, drugs are carried away by air currents and deposited on the surface of the reservoir.
A significant source of pollution of water bodies with oil and oil products is the oil industry. Oil enters water bodies when oil products spilled onto the surface of the earth are washed away by rain and melt water, when oil pipelines break, with wastewater from enterprises, etc.
Acid rain poses a great danger to water bodies.
The influence of oil on a reservoir.
Poorly treated oil-containing wastewater contributes to the formation of an oil film 0.4-1 mm thick on the surface of the reservoir.
One ton of oil can cover from 150 to 210 hectares of a reservoir. In the presence of an oil film, the amount of oxygen dissolved in water drops sharply, because the oxygen contained in the water is spent on the oxidation of petroleum products, and the new portion does not dissolve.
A decrease in O2 has a dramatic effect on the life of organisms and fish. Depression of fish respiration is observed at an O2 content of 4.5 mg/l, and some even at 6-7.5 mg/l.
From the oil film on the surface of a reservoir, light fractions evaporate, water-soluble fractions dissolve in water, and heavy fractions stick to solid particles suspended in water and settle to the bottom and accumulate there.
The heavy residues that have sunk to the bottom continue to depress the life of the reservoir: some of them decompose at the bottom, polluting the water with soluble decay products, and some are brought back to the surface with gases released from the bottom. Each bubble of bottom gas, coming to the surface of the water, bursts, forming an oil slick.
The formation of bottom sediment leads to the poisoning of zoo- and phytoplankton, which serves as food for fish.
Oil and petroleum products give water an oily smell and taste, as a result of which the water in the reservoir becomes unsuitable for water supply.
If there is 0.2-0.4 mg/l of oil in water, the water acquires an oily smell, which is not eliminated even with filtration and chlorination. Oil smell travels longer distances than any other pollutant.
Light fractions of oil, especially aromatic hydrocarbons, are the most toxic to fish. They are able to accumulate in fish tissues and, when entering the human body, cause the formation of a carcinogenic protein complex in fat cells. Fry hatched from the eggs of contaminated fish have mutagenic disorders (absence of gills, two heads, etc.)
PROTECTION OF THE HYDROSPHERE
Surface water protects against clogging, pollution and depletion. To protect against clogging, prevent various solid waste and other objects from entering surface water bodies and rivers. To protect against depletion, the minimum permissible water flows are controlled. Used to protect against contamination next events:
- ? development of waste-free and water-free technologies and recycling water supply;
- ? wastewater treatment (industrial, municipal, etc.);
- ? injection of wastewater into deep aquifers (underground disposal);
- ? purification and disinfection of surface water used for water supply and other purposes.
Waste-free and water-free technologies and recycling water supply. The main pollutant of surface waters is wastewater. Most in an efficient way protection of surface waters from pollution by wastewater are waterless and waste-free technologies. On initial stage is created recycling water supply. Its system includes a number of treatment facilities and installations, which creates a closed cycle of wastewater use, which with this method is constantly in circulation and does not end up in surface water bodies.
Cleaning of drains. Exist various ways wastewater treatment: mechanical, physical-chemical, chemical, biological and thermal. Depending on the type of wastewater, its purification can be carried out using one or a combination of methods, including treatment of sludge (or excess biomass) and disinfection of wastewater before discharging it into a reservoir.
Mechanical cleaning based on straining, settling and filtering. At the same time, insoluble mechanical impurities are removed from wastewater: sand, clay particles, scale, etc. Physico-chemical cleaning involves coagulation, sorption, flotation, extraction and other methods. Fine suspended particles, mineral and organic matter. Chemical cleaning based on the processes of neutralization, oxidation, ozonation, chlorination. Wastewater is purified from toxic substances and microorganisms. Biological (biochemical) treatment is based on the ability of microorganisms to use many organic and inorganic compounds from wastewater (hydrogen sulfide, ammonia, nitrites, etc.) for their nutrition. TO thermal methods are used for the treatment of industrial wastewater containing mainly highly toxic organic components that are destroyed at high temperatures.
All wastewater treatment methods require treatment and disposal of the resulting sludge and sediment (especially when treating toxic industrial wastewater). For this purpose, they are stored in special landfills, processed in biological structures, processed using plants (hyacinths, reeds, etc.) or burned in special furnaces.
Wastewater is pumped into deep aquifers (underground disposal) through a system of absorption wells. With this method, there is no need for expensive treatment and disposal of wastewater and the construction of treatment facilities.
Agroforestry and hydraulic engineering measures protect surface waters from pollution and clogging. They prevent eutrophication of lakes, reservoirs and small rivers, erosion, landslides, bank collapse, and reduce polluted surface runoff.
Water protection zones protect surface waters from pollution, clogging and depletion. They are created on all water bodies. Their width on rivers ranges from 0.1 to 1.5-2.0 km, including the river floodplain, terraces and coastal slope. Within these zones, plowing of land, grazing of livestock, use of pesticides and fertilizers, construction work, etc. are prohibited.
Groundwater is protected from pollution and depletion. To protect against exhaustion use:
- ? regulation of groundwater intake regime;
- ? rational placement of water intakes by area;
- ? determining the amount of operational reserves as the limit of their rational use;
- ? introduction of a crane mode for the operation of self-flowing artesian wells, etc.
To protect groundwater from pollution, two groups of measures are used: preventive and special.
Preventive actions aimed at preventing pollution. They provide a device sanitary protection zones (SZZ) - territories around sources of centralized drinking water supply, created to eliminate the possibility of groundwater pollution.
Special Events aimed at localizing or eliminating the source of pollution. They provide for the isolation of sources of pollution from the rest of the aquifer (curtains, impervious walls), as well as for the interception of contaminated groundwater using drainage. To eliminate local sources of pollution, long-term pumping of contaminated groundwater is carried out.
The fundamentals of water legislation prohibit the design, construction and commissioning of enterprises that are not equipped with water treatment devices. Discharge of waste water is permitted only with the permission of water quality control authorities.
Test questions and assignments
- 1. What are the main anthropogenic impacts on the hydrosphere?
- 2. What is water pollution called?
- 3. What causes natural and anthropogenic water pollution?
- 4. Describe the main types of water pollution.
- 5. Describe environmental impact pollution of freshwater and marine ecosystems.
- 6. Highlight the causes, negative consequences and ways to prevent the development of eutrophication and algal blooms, “red tides”.
- 7. Describe the environmental consequences of groundwater and surface water depletion.
- 8. Describe the main measures aimed at protecting the hydrosphere.
The hydrosphere includes all the Earth's water resources:
- World Ocean;
- The groundwater;
- swamps;
- rivers;
- lakes;
- seas;
- reservoirs;
- glaciers;
- atmospheric steam
All these resources belong to the conditionally inexhaustible benefits of the planet, but anthropogenic activities can significantly worsen the condition of water. For the hydrosphere global problem represents pollution of all water areas. Water environment polluted by petroleum products and agricultural, industrial and solid fertilizers household waste, heavy metals and chemical compounds, radioactive waste and biological organisms, warm, municipal and industrial wastewater.
Water purification
In order to preserve water resources on the planet and not deteriorate water quality, it is necessary to protect the hydrosphere. To do this, it is necessary to rationally use resources and purify water. Depending on the purification methods, you can obtain drinking or industrial water. In the first case, it is cleared of chemical substances, mechanical impurities and microorganisms. In the second case, it is necessary to remove only harmful impurities and those substances that cannot be used in the area in which process water will be used.
There are quite a few methods of water purification. IN various countries Various methods of water purification are used. Today, mechanical, biological and chemical methods of water treatment are relevant. Oxidation and reduction purification, aerobic and anaerobic methods, sludge treatment, etc. are also used. The most promising purification methods are physicochemical and biochemical water purification, but they are expensive and therefore are not widely used.
Closed water cycles
To protect the hydrosphere, closed water circulation cycles are created, and for this, natural waters are used, which are pumped into the system once. After use, the water is returned to natural conditions, and it is either purified or mixed with water from the natural environment. This method allows you to reduce water consumption by up to 50 times. In addition, already used recycled water, depending on its temperature, is used as a coolant or coolant.
Thus, the main measures to protect the hydrosphere are its rational use and purification. In accordance with the technologies used, the optimal amount of water resources is calculated. The more economically water is used, the higher its quality in nature will be.
Geography tests, grade 10
Option 1
1) Polymetallic ores
2) Nuclear energy
3) Sea water
4) Forest resources
A2 Which statement about the availability of natural resources is true?
1) Cultivable lands occupy 70% of the world's land fund
2) Fresh water resources account for 40% of the total volume of the hydrosphere
3) Arable lands are mainly distributed in forest, forest-steppe and steppe zones
4) There are about 6 thousand coal mines in the world
A3 The “tin belt” includes states
1) Algeria, Egypt
2) Thailand, Malaysia
3) Zambia, Zimbabwe
4) Iraq, Kuwait
A4 The most effective way to overcome water shortages is
1) Rational use of water resources
2) Desalination of the waters of the World Ocean
3) Transportation of icebergs
4) Reducing water consumption by the population
A5 Contributes to nature conservation
1) Widespread development of electric transport
2) Creation of cascades of hydroelectric power stations on rivers
3) Conversion of thermal power plants from gas to coal
4) Development of intensive agriculture in the wet zone equatorial forests
A6 Contributes to the protection of the hydrosphere
1) Limiting the use of mineral fertilizers
2) Irrigation of fields
3) Draining swamps
4) Creation of artificial channels
A7 Soil salinity is typical for natural area
1) Deserts and semi-deserts
4) Wet tropical forests
A8 An example of rational environmental management is
1) Transportation of petroleum products on sea vessels
2) Land reclamation in coal mining areas
3) Disposal of nuclear waste at landfills
4) Creation of reservoirs on lowland rivers
A9 Areas of cultivated land prevail in countries
1) North Africa
2) South Asia
3) Australia
4) Latin America
A10 Which statement about environmental management is true?
1) Floating wood along rivers is the most environmentally friendly way to transport it
2) Waste disposal is an environmentally friendly technology
3) Only animals are protected in nature reserves
4) The construction of reservoirs on rivers does not have any negative impact on nature
A11 A special type of protected areas with little changed picturesque landscapes, with rich flora and fauna, where nature protection is combined with the recreational functions of the territory, is called
1) Reserve
3) Reserve
4) National natural park
1) Exhaustible non-renewable A) solar energy
2) Inexhaustible B) fresh water
3) Exhaustible renewable B) uranium
Q2 Which three natural resources are considered inexhaustible?
1) Climatic
2) Flow energy
3) Wind energy
4) Soil
Q3 Arrange regions according to their increasing share in global geological reserves natural gas
1) America
2) Foreign Europe
3) Foreign Asia
Q4 Select from the listed countries three countries that are leaders in proven oil reserves
1) Saudi Arabia
2) Venezuela
6) Australia
Q5 Which three countries are the leaders in the world in terms of arable land area?
1) USA 4) Mexico
2) Niger 5) Russia
3) India 6) Argentina
Q6 Rank the regions of the world by decreasing forest area
1) Foreign Europe
2) Foreign Asia
4) Latin America
C1. What are the negative consequences of the construction of reservoirs on lowland rivers? Specify at least two consequences _________________________________________________
C2 It is known that among the economic regions of Russia, the leader in air pollution with sulfur dioxide is the East Siberian economic region. Which sectors of the economy are associated with such pollution? Please provide at least two reasons.
Option 2
Choose one correct answer
A1 An example of an exhaustible renewable natural resource is
1) Brown coal
2) Nuclear power
3) Forest resources
4) Sea water
A2 Which statement about the provision of natural resources to the countries of the world is true?
1) China has the largest coal reserves
2) On the territory Saudi Arabia the largest bauxite deposits are located
3) The rivers of Southern Europe have hydroelectric potential
4) Mexico is a leader in industrial timber harvesting
A3 The main area of phosphorite mining among those listed is
1) India, Madagascar
2) O. Nauru, Morocco
3) Argentina, Australia
4) Suriname, Venezuela
A4 Specially protected areas, completely withdrawn from them economic use, where systematic scientific observations are carried out, are
2) Reserves
3) Wildlife sanctuaries
4) Natural monuments
A5 Flooding and waterlogging of land most often occurs
1) When open mining mineral
2) As a result of deforestation
3) When creating reservoirs
4) As a result of improper soil treatment
A6 Soil salinity is mainly caused by
1) Incorrect plowing
2) Improper irrigation
3) Draining swamps
4) Violation of crop rotation
A7 The main source of ocean pollution is
1) Fish processing waste
2) Household waste
3) Oil transport
4) Harvesting sea animals
A8 Pasture areas predominate in
1) North Africa
2) South Asia
3) Australia
A9 Has a high share of forests per capita
A10 An example of rational environmental management is
1) Conversion of road transport to gas
2) Draining swamps
3) Creation of closed cycles in production
4) Construction of high pipes in enterprises
A11 Areas of territory permanently withdrawn from economic use to preserve everything in its natural state natural complex, called
1) Wildlife sanctuaries
2) Forestries
3) National natural parks
4) Nature reserves
B1 Establish a correspondence between the types of natural resources and the natural resources to which they belong
Type of natural resources Natural resources
1) Exhaustible non-renewable A) geothermal energy
2) Inexhaustible B) fish
3) Exhaustible renewable B) apatites
Q2Rank lands according to their decreasing share in the area of the world land fund
1) Arable land, gardens
2) Unproductive lands
3) Meadows, pastures
Q3 Select from the listed countries three countries that are leaders in total geological coal reserves
1) Indonesia 4) Venezuela
2) Libya 5) China
3) USA 6) Australia
Q4 Rank the regions of the world by decreasing share of world oil reserves
2) Latin America
3) Foreign Asia
4) Australia and Oceania
Q5 Rank the regions of the world by decreasing share of the world's fresh water resources
Q6 Select three examples of unsustainable environmental management
1) Conversion of thermal power plants to gas
2) Use of waste as secondary raw materials
3) Terracing of slopes
4) Burial of toxic substances in deep-sea depressions
5) Increasing the size of whaling
6) Creation of mine waste heaps
C1 It is known that the application of nitrogen fertilizers to the soil has negative consequences, especially in cases where the dose of these fertilizers is significant. Indicate at least two negative consequences that such chemical reclamation leads to
C2 Being a powerful stimulus for the development of global transport, road transport is one of the main sources of environmental pollution. Which negative consequences leads to an increase in the number of road transport? Please provide at least two reasons
Option 1
A1 – 4 B1 – 1-B, 2-A, 3 - B
A2 -3 B2 – 1,2,3
A3-2 B3 – 2,4,1,3
A4- 1 B4 -1,2,4
A5 – 1 B5 – 1,3,5
A6- 1 B6 – 4,2,3,1
A8 -2 A10 – 2 A 11 – 4
C1 – Leads to disruption of the ecological balance in the area. Consequences: rising groundwater, changes in microclimate, changes in river flow speed, changes in flora and fauna, destruction of banks
Loading...
