Reducing the biospheric functions of water bodies. Changes in the physical and organoleptic properties of water. Pollution of the hydrosphere and its main types. The main sources of pollution of surface and ground waters. Depletion of underground and surface waters of reservoirs.

St. Petersburg

Humanitarian University of Trade Unions

Control work on the subject:Ekology

Topic: Danger of water pollution for humans

Completed by: Yarov E.N.

Faculty of Culture

Specialty: Social Job

Correspondence faculty

St. Petersburg

1. INTRODUCTION.

2. Pollution of the hydrosphere.

3. Main types of pollution

4. The main sources of pollution of surface and ground waters.

5. Ecological consequences of pollution of the hydrosphere.

6. Depletion of underground and surface waters.

7. Protection of the hydrosphere.

8. Conclusion.

1. INTRODUCTION

Water and life are inseparable concepts. Therefore, the abstract of this topic is immense, and I consider only some, especially topical problems.

The existence of the biosphere and man has always been based on the use of water. Mankind has constantly sought to increase water consumption, exerting a huge multilateral impact on the hydrosphere.

At the current stage of development of the technosphere, when the human impact on the hydrosphere is increasing in the world, and natural systems have largely lost their protective properties, new approaches are obviously needed, ecologolization of thinking, “awareness of the realities and trends that have appeared in the world in relation to nature in as a whole and its components. This fully applies to the awareness of such a terrible evil as pollution and depletion of waters in our time.

2. Pollution of the hydrosphere

To begin with, I want to give a brief definition of such a concept as pollution of water bodies. Pollution of water bodies is understood as a decrease in their biospheric functions and ecological significance as a result of the entry of harmful substances into them.

Water pollution is manifested in a change in physical and organoleptic properties (violation of transparency, color, smell, taste), an increase in the content of sulfates, chlorides, nitrates, toxic heavy metals, a reduction in air oxygen dissolved in water, the appearance of radioactive elements, pathogenic bacteria and other pollutants.

Our country has one of the highest water potentials in the world - each inhabitant of Russia has over 30 thousand m 3 /year of water. At the same time, today, due to pollution or clogging, which in total is the same, about 70% of the rivers and lakes of Russia have lost their qualities as sources of drinking water supply, as a result, about half of the population consumes polluted poor-quality water, which is naturally one of the main reasons for the decline habitability of each person. In 1998 alone, industrial, municipal and agricultural enterprises discharged 60 km 3 of wastewater into the surface water bodies of Russia, 40% of which were classified as polluted. Only a tenth of them underwent regulatory clearance. The historical balance in the water environment of Lake Baikal, the most unique lake on our planet, which, according to scientists, could provide clean water to all mankind for almost half a century, has been disturbed. Over the past 15 years alone, more than 100 km 3 of Baikal water has been polluted. More than 8500 tons of oil products, 750 tons of nitrates, 13 thousand tons of chlorides and other pollutants were annually supplied to the water area of ​​the lake. Scientists believe that only the size of the lake and the huge volume of water mass, as well as the ability of biota to participate in self-purification processes, save the Baikal ecosystem from complete degradation.

It has been established that more than 400 types of substances can cause water pollution. If the permissible norm is exceeded by at least one of the three indicators of harmfulness: sanitary-toxicological, general sanitary or organoleptic, the water is considered contaminated.

There are chemical, biological and physical pollutants. Among the chemical pollutants, the most common are oil and oil products, surfactants (synthetic surfactants), pesticides, heavy metals, dioxins. Biological pollutants, such as viruses and other pathogens, and physical pollutants, radioactive substances, heat, etc., pollute water very dangerously.

3. Main types of pollution

The most common chemical and bacterial pollution of water. Radioactive, mechanical and thermal pollution is observed much less frequently. Chemical pollution is the most common, persistent and far-reaching. It can be organic (phenols, naphthenic acids, pesticides, etc.) and inorganic (salts, acids, alkalis), toxic (arsenic, mercury compounds, lead, cadmium, etc.) and non-toxic. When deposited on the bottom of reservoirs or during filtration in the reservoir, harmful chemicals are sorbed by rock particles, oxidized and reduced, precipitated, etc., however, as a rule, polluted waters do not completely self-purify. The source of chemical contamination of groundwater in highly permeable soils can extend up to 10 km or more. Bacterial pollution is expressed in the appearance of pathogenic bacteria, viruses (up to 700 species), protozoa, fungi, etc. in the water. This type of pollution is temporary.

The content in water, even at very low concentrations, of radioactive substances that cause radioactive contamination is very dangerous. The most harmful are "long-lived" radioactive elements that have an increased ability to move in water (strontium-90, uranium, radium-226, cesium, etc.). Radioactive elements get into surface water bodies when radioactive waste is dumped into them, waste is buried at the bottom, etc. Uranium, strontium and other elements get into groundwater as a result of their fall to the surface of the earth in the form of radioactive products and waste and subsequent seepage into the depths of the earth together with atmospheric waters, and as a result of the interaction of groundwater with radioactive rocks. Mechanical pollution is characterized by the ingress of various mechanical impurities into the water (sand, sludge, silt, etc.). Mechanical impurities can significantly worsen the organoleptic properties of water.

In relation to surface waters, they are also polluted with garbage, timber rafting residues, industrial and domestic wastes, which worsen the quality of waters, negatively affect the living conditions of fish, and the state of ecosystems.

Thermal pollution is associated with an increase in the temperature of waters as a result of their mixing with warmer surface or process waters. With an increase in temperature, a change in the gas and chemical composition in the waters occurs, which leads to the multiplication of anaerobic bacteria, the growth of hydrobionts and the release of toxic gases - hydrogen sulfide, methane. At the same time, the hydrosphere is polluted by the “blooming” of water, as well as the accelerated development of microflora and microfauna, which contributes to the development of other types of pollution.

According to existing sanitary standards, the temperature of the reservoir should not rise by more than 3 ° C in summer and 5 ° C in winter, and the thermal load on the reservoir should not exceed 12--17 kJ / m 3.

4. Main sources of pollutionI surface and ground water

The greatest harm to water bodies and streams is caused by the release of untreated wastewater into them - industrial, domestic, collector-drainage, etc. Industrial wastewater pollutes ecosystems with a wide variety of components, depending on the specifics of industries. It should be noted that today the volume of industrial wastewater discharges into many aquatic ecosystems not only does not decrease, but continues to grow. So, for example, in the lake. Baikal, instead of the planned cessation of wastewater discharges from the pulp and paper mill and their transfer to a closed water consumption cycle, a huge amount of wastewater is being discharged.

Municipal wastewater in large quantities comes from residential and public buildings, laundries, canteens, hospitals, etc. This type of wastewater is dominated by various organic substances as well as microorganisms, which can cause bacterial contamination.

Such hazardous pollutants as pesticides, ammonium and nitrate nitrogen, phosphorus, potassium, etc. are washed away from agricultural areas, including areas occupied by livestock complexes. For the most part, they enter water bodies and streams without any treatment, and therefore have a high concentration of organic matter, nutrients and other pollutants.

Significant danger is posed by gas-smoke compounds (aerosols, dust, etc.) settling from the atmosphere onto the surface of watersheds and directly onto water surfaces. The density of deposition, for example, of ammonium nitrogen in the European territory of Russia is estimated at an average of 0.3 t / km 2, and sulfur from 0.25 to 2.0 t / km 2. The scale of oil pollution of natural waters is enormous. Millions of tons of oil annually pollute marine and freshwater ecosystems during oil tanker accidents, in oil fields in coastal areas, when ballast water is discharged from ships, etc.

In addition to surface water, groundwater is also constantly polluted, primarily in the areas of large industrial centers. Sources of groundwater pollution are very diverse.

Pollutants can penetrate to groundwater in various ways: through seepage of industrial and domestic wastewater from storage facilities, storage ponds, settling ponds, etc., through the annulus of faulty wells, through absorbing wells, sinkholes, etc.

Natural sources of pollution include highly mineralized (salty and brine) groundwater or sea water, which can be introduced into fresh unpolluted water during the operation of water intake facilities and pumping water from wells.

It is important to emphasize that groundwater pollution is not limited to the area of ​​industrial enterprises, waste storage facilities, etc., but spreads downstream to distances of up to 20–30 km or more from the pollution source. This poses a real threat to the drinking water supply in these areas.

It should also be borne in mind that groundwater pollution has a negative impact on the ecological state of surface water, atmosphere, soil, and other components of the natural environment. For example, contaminants found in groundwater can be carried by seepage flow to surface water bodies and pollute them. As emphasized by V.M. Goldberg (1988), the circulation of pollutants in the system of surface and ground waters predetermines the unity of environmental and water protection measures and they cannot be broken. Otherwise, measures to protect groundwater without regard to measures to protect other components of the natural environment will be ineffective.

5. Ecological consequences of hydrosphere pollution

Pollution of aquatic ecosystems is a great danger to all living organisms and, in particular, to humans. In my work, I want to start first of all with freshwater reservoirs.

It has been established that under the influence of pollutants in freshwater ecosystems, there is a drop in their stability, due to the violation of the food pyramid and the breakdown of signaling links in the biocenosis, microbiological pollution, eutrophication and other extremely unfavorable processes. They reduce the growth rate of aquatic organisms, their fertility, and in some cases lead to their death.

Accelerated, or so-called anthropogenic, eutrophication is associated with the entry into water bodies of a significant amount of biogenic substances - nitrogen, phosphorus and other elements in the form of fertilizers, detergents, animal waste, atmospheric aerosols, etc. Under modern conditions, eutrophication of water bodies proceeds in a much shorter period of time - several decades or less.

Anthropogenic eutrophication has a very negative effect on freshwater ecosystems, leading to a restructuring of the trophic relationships of aquatic organisms and a sharp increase in phytoplankton biomass. Due to the mass reproduction of blue-green algae, causing the "bloom" of water, its quality and living conditions of aquatic organisms are deteriorating (besides, they emit toxins dangerous to humans). An increase in the mass of phytoplankton is accompanied by a decrease in the diversity of species, which leads to an irreplaceable loss of the gene pool, a decrease in the ability of ecosystems to homeostasis and self-regulation.

The processes of anthropogenic eutrophication cover many large lakes of the world - the Great American Lakes, Balaton, Ladoga, Geneva, etc., as well as reservoirs and river ecosystems, primarily small rivers. On these rivers, in addition to the catastrophically growing biomass of blue-green algae from the banks, they are overgrown with higher vegetation. The blue-green algae themselves, as a result of their vital activity, produce the strongest toxins that are dangerous for aquatic organisms and humans.

In addition to an excess of biogenic substances, other pollutants also have a detrimental effect on freshwater ecosystems: heavy metals (lead, cadmium, nickel, etc.), phenols, surfactants, etc. chemical compounds of the tributaries of the lake, turned out to be incapable of processing chemical compounds alien to natural waters (petroleum products, heavy metals, salts, etc.). As a result, depletion of aquatic organisms, a decrease in the biomass of zooplankton, the death of a significant part of the population of the Baikal seal, etc., were noted.

Marine ecosystems. The rate at which pollutants enter the oceans has increased dramatically in recent years. Every year up to 300 billion m 3 of sewage is discharged into the ocean, 90% of which is not subjected to preliminary treatment.

Marine ecosystems are exposed to increasing anthropogenic impact through chemical toxicants, which, accumulating by hydrobionts along the trophic chain, lead to the death of consumers of even high orders, including terrestrial animals - seabirds, for example.

Among chemical toxicants, petroleum hydrocarbons, pesticides and heavy metals (mercury, lead, cadmium, etc.) pose the greatest danger to marine biota and humans.

The environmental consequences of pollution of marine ecosystems are expressed in the following processes and phenomena:

Violation of the stability of ecosystems;

Progressive eutrophication;

The appearance of "red tides";

Accumulation of chemical toxicants in biota;

Decreased biological productivity;

The emergence of mutagenesis and carcinogenesis in the marine environment;

Microbiological pollution of coastal areas of the sea.

To a certain extent, marine ecosystems can withstand the harmful effects of chemical toxicants using the accumulative, oxidizing and mineralizing functions of aquatic organisms. For example, bivalve mollusks are able to accumulate one of the most toxic pesticides, DDT, and, under favorable conditions, remove it from the body. (DDT is known to be banned in Russia, the United States and some other countries, however, it enters the World Ocean in significant quantities.) Scientists have also proved the existence of intense biotransformation of benzapyrene in the waters of the World Ocean, due to the presence in open and semi-enclosed water areas heterotrophic microflora. It has also been established that the microorganisms of reservoirs and bottom sediments have a sufficiently developed mechanism of resistance to heavy metals, in particular, they are able to produce hydrogen sulfide, extracellular exopolymers and other substances that, interacting with heavy metals, convert them into less toxic forms.

At the same time, more and more toxic pollutants are entering the ocean, and the problems of eutrophication and microbiological pollution of coastal zones of the ocean are becoming increasingly acute. In this regard, it is important to determine the allowable anthropogenic pressure on marine ecosystems, to study their assimilation capacity as an integral characteristic of the ability of biogeocenosis to dynamically accumulate and remove pollutants.

For human health, the adverse effects of the use of polluted water, as well as contact with it (bathing, washing, fishing, etc.) are manifested either directly when drinking, or as a result of biological accumulation in authentic food chains such as water - plankton - fish - - man or water - soil - plants - animals - man, etc.

In modern conditions, the danger of such epidemic diseases as cholera, typhoid fever, dysentery, etc., caused by bacterial contamination of water, is also increasing.

6. Depletion of ground and surface waters

Water depletion should be understood as an unacceptable reduction in their reserves within a certain territory (for groundwater) or a decrease in the minimum allowable flow (for surface waters). Both of them lead to unfavorable ecological consequences, violate the established ecological ties in the human-biosphere system.

Practically in all large industrial cities of the world, including Moscow, St. Petersburg, Kyiv, Kharkov, Donetsk and other cities, where groundwater was exploited by powerful water intakes for a long time, significant depression funnels (depressions) with radii of up to 20 km or more . For example, increased groundwater abstraction in Moscow led to the formation of a huge regional depression with a depth of up to 70–80 m, and in some areas of the city up to 110 m or more. All this ultimately leads to a significant depletion of groundwater.

According to the State Water Cadastre, in the 1990s, over 125 million m 3 /day were taken in our country during the operation of water intakes. As a result, in large areas, the conditions for the relationship of groundwater with other components of the natural environment have changed dramatically, and the functioning of terrestrial ecosystems has been disrupted. Intensive exploitation of groundwater in areas of water intake and powerful drainage from mines and quarries leads to a change in the relationship between surface and groundwater, to significant damage to river flow, to the cessation of the activity of thousands of springs, many dozens of streams and small rivers. In addition, due to a significant decrease in groundwater levels, other negative changes in the environmental situation are also observed: wetlands with a large species diversity of vegetation are being drained, forests are drying up, moisture-loving vegetation is dying - hygrophytes.

So, for example, at the Aidos water intake in Central Kazakhstan, a decrease in groundwater occurred, which caused the drying and death of vegetation, as well as a sharp reduction in transpiration flow. Hydrophytes (willow, reed, cattail, chaevik) died out rather quickly, even plants with a deeply penetrating root system (wormwood, wild rose, Tatar honeysuckle, etc.) partially died; tugai thickets have grown. The artificial lowering of the groundwater level, caused by intensive pumping, also affected the ecological state of the parts of the river valley adjacent to the water intake. The same anthropogenic factor can lead to an acceleration of the succession series change time, as well as to the loss of its individual stages.

Long-term intensification of water intakes in certain geological and hydrogeological conditions can cause slow subsidence and deformation of the earth's surface. The latter negatively affects the state of ecosystems, especially coastal areas, where low areas are flooded, and the normal functioning of natural communities of organisms and the entire human habitat is disrupted.

To all of the above, groundwater is being depleted. The depletion of groundwater is also facilitated by the long-term uncontrolled self-discharge of artesian water from wells.

The depletion of surface waters is manifested in a progressive decrease in their minimum allowable flow. On the territory of Russia, the surface runoff of water is distributed extremely unevenly. About 90% of the total annual runoff from the territory of Russia is discharged to the Arctic and Pacific oceans, while the internal runoff basins (Caspian and Azov Seas), where over 65% of the Russian population lives, account for less than 8% of the total annual runoff.

It is in these areas that the depletion of surface water resources is observed, and the shortage of fresh water continues to grow. This is due not only to unfavorable climatic and hydrological conditions, but also to the intensification of human economic activity, which leads to ever-increasing water pollution, a decrease in the ability of water bodies to self-purify, depletion of groundwater reserves, and, consequently, to a decrease in spring flow that feeds watercourses and reservoirs.

Let's not forget about one of the main environmental problems - the restoration of water content and cleanliness of small rivers (no more than 100 km long), the most vulnerable link in river ecosystems. They were the most susceptible to anthropogenic impact. The ill-conceived economic use of water resources and adjacent land has caused their depletion (and often disappearance), shallowing and pollution.

At present, the state of small rivers and lakes, especially in the European part of Russia, as a result of a sharply increased anthropogenic load on them, is catastrophic. The flow of small rivers has decreased by more than half, the water quality is unsatisfactory. Many of them have completely ceased to exist.

Other very significant types of human impact on the hydrosphere include: the creation of large reservoirs that radically transform the natural environment in the adjacent territories, and the withdrawal for economic purposes of a large amount of water from rivers flowing into water bodies, which leads to the reduction and drying up of many inland water bodies (Aral sea, Dead Sea, etc.).

The creation of large reservoirs, especially of the flat type, for the accumulation and regulation of surface runoff leads to multidirectional consequences in the natural environment.

It should be taken into account that the creation of reservoirs by blocking the channel of watercourses by dams is fraught with serious negative consequences for most hydrobionts. Due to the fact that many fish spawning grounds are cut off by dams, the natural reproduction of many salmon, sturgeon and other anadromous fish is drastically worsened or stopped.

The withdrawal of a large amount of water from rivers flowing into reservoirs for economic purposes also leads to very serious negative environmental consequences. Thus, the level of the once abundant Aral Sea, starting from the 1960s, has been catastrophically decreasing due to the unacceptably high water withdrawal from the Amudarya and Syrdarya. As a result, the volume of the Aral Sea has decreased by more than half, the sea level has decreased by 13 m, and the salinity of the water (mineralization) has increased by 2.5 times.

Academician B.N. Laskarin spoke about the tragedy of the Aral Sea as follows: “We stopped at the very edge of the abyss ... The Aral was destroyed, one might say purposefully. There was even a certain anti-scientific hypothesis, according to which the Aral Sea was considered a mistake of nature. Allegedly, he interfered with the development of the water resources of the Syr Darya and Amu Darya (they said that, taking their water, the Aral evaporates it into the air). The supporters of this idea did not think about fish, nor that the Aral Sea is the center of an oasis.”

The drained bottom of the Aral Sea is becoming the largest source of dust and salts today. In the delta of the Amudarya and Syrdarya, in place of dying tugai forests and reed beds, barren solonchaks appear.

The transformation of phytocenoses on the shores of the Aral Sea and in the deltas of the Amudarya and Syrdarya occurs against the background of the drying up of lakes, channels, swamps and the widespread decrease in the level of groundwater due to a drop in sea level. In general, water re-absorption from the Amudarya and Syrdarya and the drop in sea level caused such ecological changes in the Aral landscape, which can be characterized as desertification.

In order to preserve and restore the Aral Sea, normalize the ecological, sanitary-hygienic and socio-economic situation in the Aral Sea region, joint efforts of the states of Central Asia and Kazakhstan are necessary to restructure the economies of these countries (refusal to focus on extremely water-intensive agricultural crops, reduce irrigated areas, etc. .), a constant focus on environmentally sustainable development.

7. Protection of the hydrosphere

And of course we must not forget about measures to protect the hydrosphere. Surface waters are protected from clogging, pollution and depletion. To prevent clogging, measures are taken to prevent the entry of construction debris, solid waste, timber rafting residues and other items into surface water bodies and rivers that adversely affect water quality, fish habitats, etc.

Depletion of surface water is prevented by strict control of the minimum allowable runoff.

The most important and most difficult problem is the protection of surface waters from pollution. To this end, the following environmental protection measures are envisaged:

Development of non-waste and waterless technologies; introduction of water recycling systems;

Wastewater treatment (industrial, municipal, etc.);

Injection of sewage into deep aquifers;

Purification and disinfection of surface waters used for water supply and other purposes.

The main pollutant of surface waters is sewage, so the development and implementation of effective wastewater treatment methods seems to be a very urgent and environmentally important task.

The most effective way to protect surface waters from pollution by sewage is the development and implementation of an anhydrous and waste-free production technology, the initial stage of which is the creation of a circulating water supply.

When organizing a recycling water supply system, it includes a number of treatment facilities and installations, which makes it possible to create a closed cycle for the use of industrial and domestic wastewater. With this method of water treatment, wastewater is always in circulation and their entry into surface water bodies is completely excluded.

Due to the huge variety of wastewater composition, there are various methods for their treatment: mechanical, physico-chemical, chemical, biological, etc. Depending on the degree of harmfulness and the nature of the pollution, wastewater treatment can be carried out by any one method or a set of methods (combined method). The treatment process involves the treatment of sludge (or excess biomass) and disinfection of wastewater before discharging it into a reservoir.

During mechanical treatment, up to 90% of insoluble mechanical impurities of various degrees of dispersion (sand, clay particles, scale, etc.) are removed from industrial wastewater by straining, settling and filtering, and up to 60% from domestic wastewater. For these purposes, gratings, sand traps, sand filters, sedimentation tanks of various types are used. Substances floating on the surface of wastewater (oil, resins, oils, fats, polymers, etc.) are retained by oil traps and other types of traps or burned out.

Chemical and physico-chemical treatment methods are the most effective for industrial wastewater treatment.

The main chemical methods include neutralization and oxidation. In the first case, special reagents (lime, soda ash, ammonia) are introduced into wastewater to neutralize acids and alkalis, in the second case, various oxidizing agents. With their help, wastewater is freed from toxic and other components.

For physical and chemical treatment, the following are used:

Coagulation - the introduction of coagulants (ammonium salts, iron, copper, sludge waste, etc.) into wastewater to form flocculent sediments, which are then easily removed; -- sorption -- the ability of certain substances (bentonite clay, activated carbon, zeolites, silica gel, peat, etc.) to absorb pollution. By the sorption method, it is possible to extract valuable soluble substances from wastewater and their subsequent disposal;

Flotation is the passage of air through wastewater. Gas bubbles capture surfactants, oil, oils, and other contaminants as they move upwards and form an easily removable foamy layer on the surface of the water.

Biological (biochemical) method is widely used for purification of municipal wastewater from pulp and paper, oil refineries, and food enterprises. The method is based on the ability of artificially introduced microorganisms to use organic and some inorganic compounds contained in wastewater (hydrogen sulfide, ammonia, nitrites, sulfides, etc.) for their development. Cleaning is carried out using natural methods (irrigation fields, silt pads, filtration fields, biological ponds, etc.) and artificial methods (aerotanks, metatanks, biofilters, circulating oxidizing channels), biological modules, etc.

After clarification of wastewater, a precipitate is formed, which is fermented in reinforced concrete tanks (methane tanks), and then removed to sludge sites for drying.

Dried sludge is usually used as a fertilizer. At the same time, many harmful substances (heavy metals, etc.) have been detected in wastewater in recent years, which excludes this method of sludge disposal. The clarified part of the wastewater is treated in aeration tanks - special closed tanks, through which wastewater enriched with oxygen and mixed with activated sludge is slowly passed. Activated sludge is a collection of heterotrophic microorganisms and small invertebrates (molds, yeasts, aquatic fungi, rotifers, etc.), as well as a solid substrate. It is important to choose the right temperature, pH, additives, mixing conditions, oxidizing agent (oxygen) in order to maximize the intensification of the hydrobiocenosis that makes up activated sludge.

After secondary settling, wastewater is disinfected (disinfected) using chlorine compounds or other strong oxidizing agents. With this method (chlorination), pathogenic bacteria, viruses, and pathogens are destroyed.

In wastewater treatment systems, the biological (biochemical) method is the final one, and after its application, wastewater can be used in circulating water supply or discharged into surface water bodies.

In recent years, new effective methods have been actively developed to promote the ecologization of wastewater treatment processes:

Electrochemical methods based on the processes of anodic oxidation and cathodic reduction, electrocoagulation and electroflotation;

Membrane purification processes (ultrafilters, electrodialysis, etc.);

Magnetic treatment to improve suspended solids flotation;

Radiation purification of water, which makes it possible to subject pollutants to oxidation, coagulation and decomposition in the shortest possible time;

Ozonation, in which wastewater does not form substances that adversely affect natural biochemical processes;

The introduction of new selective types of sorbents for the selective separation of useful components from wastewater for recycling, etc.

It is known that a significant role in the pollution of water bodies is played by pesticides and fertilizers washed off by surface runoff from agricultural land. To prevent the ingress of polluting effluents into water bodies, a set of measures is required, including:

1) compliance with the norms and terms of applying fertilizers and pesticides;

2) focal and tape treatment with pesticides instead of continuous;

3) application of fertilizers in the form of granules and, if possible, together with irrigation water;

4) replacement of pesticides by biological methods of plant protection, etc.

It is very difficult to dispose of livestock waste, which has a detrimental effect on aquatic ecosystems. Currently, the technology is recognized as the most economical, in which harmful effluents are separated by centrifugation into solid and liquid fractions. At the same time, the solid part turns into compost and is taken out to the fields. The liquid part (slurry) with a concentration of up to 18% passes through the reactor and turns into humus. When organics decompose, methane, carbon dioxide and hydrogen sulfide are released. The energy of this biogas is used to produce heat and energy.

One of the promising ways to reduce pollution of surface waters is the injection of wastewater into deep aquifers through a system of absorption wells (underground disposal). With this method, there is no need for expensive treatment and disposal of wastewater and for the construction of treatment facilities.

At the same time, according to many leading experts in this field, this method is appropriate for isolating only small amounts of highly toxic wastewater that cannot be treated by existing technologies. These concerns are related to the fact that it is very difficult to assess the possible environmental impacts of increased flooding of even well-isolated deep groundwater aquifers. In addition, it is technically very difficult to completely exclude the possibility of the penetration of removed highly toxic industrial effluents onto the earth's surface or into other aquifers through the annulus of wells. And yet, in the foreseeable future, such a solution to environmental problems is inevitable as the lesser evil.

Among the water protection problems, one of the most important is the development and implementation of effective methods of disinfection and purification of surface water used for drinking water supply. Inadequately purified drinking water is dangerous both from an environmental and social point of view.

Since 1896 and up to the present time, the method of water disinfection with chlorine has been the most common method of combating bacterial pollution in our country. At the same time, it turned out that chlorination of water carries a serious danger to human health.

It is possible to eliminate this effect hazardous to human health and achieve a reduction in the content of carcinogens in drinking water by replacing primary chlorination with ozonation or treatment with ultraviolet rays, by refusing primary chlorination, as well as by using chemical-free cleaning methods in biological reactors (State Report "Drinking Water", 1995).

It should be noted that water treatment with ozone or ultraviolet rays has almost completely replaced chlorination at water treatment plants in many countries of Western Europe. In our country, the use of these environmentally efficient technologies is limited due to the high cost of retrofitting water treatment plants.

The modern technology of purification of drinking water from other environmentally hazardous substances - petroleum products, surfactants, pesticides, organochlorine and other compounds is based on the use of sorption processes using activated carbons or their analogues - graphite-mineral sorbents.

Agroforestry and hydrotechnical measures are becoming increasingly important in the protection of surface waters from pollution and clogging. With their help, it is possible to prevent siltation and overgrowth of lakes, reservoirs and small rivers, as well as the formation of landslide erosion, bank collapse, etc. The implementation of a set of these works will reduce polluted surface runoff and contribute to the cleanliness of water bodies. In this regard, great importance is attached to reducing the processes of eutrophication of water bodies, in particular reservoirs of such hydrotechnical cascades as Volokamsky and others.

An important protective function in any water body is performed by water protection zones. The width of the water protection zone of rivers can range from 0.1 to 1.5-2.0 km, including the river floodplain, terraces and the slope of the river banks. The purpose of the water protection zone is to prevent pollution, clogging and depletion of the water body. Plowing of land, grazing, the use of pesticides and fertilizers, construction work, etc., are prohibited within the water protection zones.

The surface hydrosphere is organically connected with the atmosphere, underground hydrosphere, lithosphere and other components of the natural environment. Given the inseparable interconnection of all its ecosystems, it is impossible to ensure the purity of surface water bodies and watercourses without protection from atmospheric pollution, groundwater nights, etc.

In order to protect surface waters from pollution, in some cases it is necessary to take drastic measures: the closure or re-profiling of polluting industries, the complete transfer of wastewater to a closed water consumption cycle, etc.

The main groundwater protection measures taken today are to prevent the depletion of groundwater reserves and protect them from pollution. As for surface waters, this large and complex problem can only be successfully solved in close connection with the protection of the entire environment.

To combat the depletion of fresh groundwater reserves suitable for drinking water supply, various measures are envisaged, including: regulation of the groundwater withdrawal regime; more rational distribution of water intakes over the area; determination of the value of operational reserves as the limit of their rational use; introduction of a crane mode of operation of self-flowing artesian wells.

Water pollution

Any actions performed by a person with water lead to a change in both its physical properties (for example, when heated) and its chemical composition (in places of industrial effluents). Over time, the substances that have fallen into the water are grouped and remain in it already in the same state. The first category includes domestic and most industrial effluents. The second group includes various types of salts, pesticides, dyes. Let's take a closer look at some of the polluting factors.

Settlements

This is one of the main factors affecting the state of water. Liquid consumption per person per day in America is 750 liters. Of course, this is not the amount that you need to drink. A person consumes water when washing, using it for cooking, using the toilet. The main drain goes to the sewer. At the same time, water pollution increases depending on the number of inhabitants living in the settlement. Each city has its own treatment facilities, in which sewage is cleaned from bacteria and viruses that can seriously harm the human body. The purified liquid is dumped into the rivers. Pollution of water with domestic wastewater is also enhanced because, in addition to bacteria, it contains food residues, soap, paper and other substances that negatively affect its condition.

Industry

Any developed state should have its own plants and factories. This is the largest factor in water pollution. The liquid is used in technological processes, it serves both for cooling and for heating the product, various aqueous solutions are used in chemical reactions. More than 50% of all discharges come from the four main consumers of the liquid: oil refineries, steel and blast furnace shops, and the pulp and paper industry. Due to the fact that the disposal of hazardous waste is often an order of magnitude more expensive than their primary treatment, in most cases, along with industrial effluents, a large amount of a wide variety of substances is discharged into water bodies. Chemical pollution of water leads to a violation of the entire ecological situation in the whole region.

thermal effect

Most power plants operate using steam energy. Water in this case acts as a coolant, after passing through the process, it is simply discharged back into the river. The temperature of the current in such places can rise by several degrees. Such an impact is called thermal water pollution, but there are a number of objections to this term, since in some cases an increase in temperature can lead to an improvement in the environmental situation.

Oil pollution of water

Hydrocarbons are one of the main sources of energy on the entire planet. The collapse of tankers, gusts on oil pipelines form a film on the water surface through which air cannot enter. Spilled substances envelop marine life, which often leads to their death. Both volunteers and special equipment are involved in the elimination of pollution. Water is a life-giving resource. It is she who gives life to almost every creature on our planet. A negligent and irresponsible attitude towards it will lead to the fact that the Earth will simply turn into a desert scorched by the sun. Already, some countries are experiencing water shortages. Of course, there are projects to use the Arctic ice, but the best solution to the problem is to reduce the overall water pollution.

The presence of fresh clean water is a necessary condition for the existence of all living organisms on the planet.

The share of fresh water suitable for consumption accounts for only 3% of its total amount.

Despite this, a person in the process of his activity mercilessly pollutes it.

Thus, a very large volume of fresh water has now become completely unusable. A sharp deterioration in the quality of fresh water occurred as a result of contamination with chemical and radioactive substances, pesticides, synthetic fertilizers and sewage, and this is already.

Types of pollution

It is clear that all types of pollution that exist are also present in the aquatic environment.

This is quite an extensive list.

In many ways, the solution to the problem of pollution will be .

heavy metals

During the operation of large factories, industrial effluents are discharged into fresh water, the composition of which is replete with various kinds of heavy metals. Many of them, getting into the human body, have a detrimental effect on it, leading to severe poisoning, death. Such substances are called xenobiotics, that is, elements that are alien to a living organism. The class of xenobiotics includes such elements as cadmium, nickel, lead, mercury and many others.

Sources of water pollution by these substances are known. These are, first of all, metallurgical enterprises, automobile plants.

Natural processes on the planet can also contribute to pollution. For example, harmful compounds are found in large quantities in the products of volcanic activity, which from time to time enter lakes, polluting them.

But, of course, the anthropogenic factor is of decisive importance here.

radioactive substances

The development of the nuclear industry has caused significant harm to all life on the planet, including fresh water reservoirs. During the activities of nuclear enterprises, radioactive isotopes are formed, as a result of the decay of which particles with different penetrating abilities (alpha, beta and gamma particles) are released. All of them are capable of causing irreparable harm to living beings, since when they enter the body, these elements damage its cells and contribute to the development of cancer.

Sources of pollution can be:

• atmospheric precipitation falling in areas where nuclear tests are carried out;
• wastewater discharged into the reservoir by nuclear industry enterprises.
• ships operating using nuclear reactors (in case of an accident).

Inorganic pollution

Compounds of toxic chemical elements are considered to be the main inorganic elements that worsen the quality of water in reservoirs. These include toxic metal compounds, alkalis, salts. As a result of the ingress of these substances into the water, its composition changes to be consumed by living organisms.

The main source of pollution is wastewater from large enterprises, factories, and mines. Some inorganic pollutants enhance their negative properties when in an acidic environment. Thus, acidic wastewater coming from a coal mine carries aluminum, copper, zinc in concentrations that are very dangerous for living organisms.

Every day, a huge amount of water from sewage flows into reservoirs.

Such water contains a lot of pollutants. These are particles of detergents, small remnants of food and household waste, feces. These substances in the process of their decomposition give life to numerous pathogenic microorganisms.

If they enter the human body, they can provoke a number of serious diseases, such as dysentery, typhoid fever.

From large cities, such effluents enter rivers and the ocean.

Synthetic fertilizers

Synthetic fertilizers used by humans contain many harmful substances such as nitrates and phosphates. Their entry into the reservoir provokes the excessive growth of a specific blue-green algae. Growing to a huge size, it prevents the development of other plants in the reservoir, while the algae itself cannot serve as food for living organisms that live in the water. All this leads to the disappearance of life in the reservoir and its swamping.

How to solve the problem of water pollution

Of course, there are ways to solve this problem.

It is known that most of the pollutants enter the water bodies together with wastewater from large enterprises. Water purification is one of the ways to solve the problem of water pollution. Business owners should attend to the installation of high-quality treatment facilities. The presence of such devices, of course, is not capable of completely stopping the release of toxic substances, but they can significantly reduce their concentration.

Also, household filters that will clean it in the house will help fight drinking water pollution.

The person himself should take care of the purity of fresh water. Following a few simple rules will help to significantly reduce the level of water pollution:

• Use tap water sparingly.
• Avoid getting household waste into the sewer system.
• Clean up nearby waterways and beaches whenever possible.
• Do not use synthetic fertilizers. The best fertilizers are organic household waste, grass clippings, fallen leaves, or compost.
• Dispose of discarded trash.

Despite the fact that the problem of water pollution is now reaching alarming proportions, it is quite possible to solve it. To do this, each person must make some efforts, treat nature more carefully.

Classmates

2 Comments

Everyone knows that the percentage of water in the human body is large and our metabolism and overall health will depend on its quality. I see ways to solve this environmental problem in relation to our country: cutting water consumption rates to a minimum, and what is over - so at inflated tariffs; the received funds should be used for the development of water treatment facilities (cleaning with activated sludge, ozonation).

Water is the source of all life. Neither humans nor animals can live without it. I did not think that the problems with fresh water are so great. But it is impossible to live a full life without mines, sewers, factories, etc. In the future, of course, humanity will have a solution to this problem, but what to do now? I believe that people should actively address the issue of water and take some action.

Oddly enough, but as civilization develops, the threat to environmental security for the entire planet grows. In particular, this concerns the pollution of water sources. It's no secret that effects of water pollution can be catastrophic for all mankind. As progress increases, the number of human needs increases, and it is possible to fully satisfy them only by increasing the volume of industrial production. But it is industrial waste that causes such sad consequences, since the current state of treatment facilities leaves much to be desired, or the necessary systems are completely absent.

According to the reports of UN experts, which are published annually on the eve of World Water Day (March 22), the number of people who get sick and die just because they use contaminated water is almost equal to the number of victims of various types of violence. And with the development of industrialization and urbanization, the degree of water pollution is only increasing. According to independent experts, at least 1.8 million children worldwide die every year from diseases caused by drinking excessively polluted water. Moreover, their age does not exceed five years.

Thus, the consequences of drinking contaminated water for humans are various intestinal and infectious diseases - cholera, typhoid, hepatitis, dysentery, gastroenteritis. In addition, water pollution leads to a deterioration in the condition of the skin, adversely affects the condition of the hair, and leads to damage to the teeth. Chlorine, which is used for drinking water in central water supply systems, very often does not react with some elements. For example, chlorine has absolutely no effect on fluorine and phenol compounds, which have a negative effect on the activity of the liver and kidneys. The kidneys and liver are the risk zone for which drinking contaminated water has the most detrimental consequences.

Negative effects of water pollution, namely, the high content of lead, cadmium, chromium, benzopyrene in it for a person is expressed in a rapid deterioration in health. The critical accumulation of these harmful elements in the body often causes oncological diseases, as well as disorders of the central and peripheral nervous systems. E. coli, enteroviruses are harmful microorganisms that have a negative impact on the functioning of the gastrointestinal tract. If water is not subjected to additional treatment, then the consequences are easy to predict - this is the development of urolithiasis and cholelithiasis, disruption of the cardiovascular system, etc. There is also a high probability of diseases with chronic nephritis and hepatitis.

In our country, today more than 50 percent of urban water supply systems have exhausted their operational life and are in an emergency-dangerous state. This, so to speak, is a consequence of their long use. Moreover, as the results of the inspections show, the vast majority of domestic industrial enterprises do not have any kind of facilities, so they dump their waste into open water bodies. Needless to say, what consequences these actions have for nature.

Therefore, in order to avoid poisoning and other negative consequences of drinking polluted water, it is necessary to take care of its purification ourselves. Of course, it is not yet a fact that water with impurities flows from your tap, but without analysis it is impossible to say with certainty that there are no impurities in it.

As for water bodies such as rivers and lakes, pollution occurs in them due to the use of various modern chemicals and fertilizers. According to scientists, 80 percent of them did not pass any tests, so it is even difficult to say what the consequences will be.

Pollutants can enter the water at any stage of the cycle, and effects of water pollution, namely its use, may not appear immediately, but after some time, while a large number of harmful elements accumulate in the body. Therefore, it is highly recommended to take care of your health by installing water purification systems in your homes.

For a long time, the problem of water pollution was not acute for most countries. The available resources were sufficient to meet the needs of the local population. With the growth of industry, the increase in the amount of water used by man, the situation has changed dramatically. Now the issues of its purification and preservation of quality are being dealt with at the international level.

Methods for determining the degree of pollution

Water pollution is commonly understood as a change in its chemical or physical composition, biological characteristics. This defines restrictions on further use of the resource. The pollution of fresh waters deserves great attention, because their purity is inextricably linked with the quality of life and human health.

In order to determine the state of water, a number of indicators are measured. Among them:

• chromaticity;
• degree of turbidity;
• smell;
• pH level;
• the content of heavy metals, trace elements and organic substances;
• coli titer;
• hydrobiological indicators;
• the amount of oxygen dissolved in water;
• oxidizability;
• the presence of pathogenic microflora;
• chemical oxygen demand, etc.

In almost all countries, there are supervisory authorities that must determine the quality from the contents at certain intervals, depending on the degree of importance of a pond, lake, river, etc. If deviations are found, the reasons that could provoke water pollution are identified. Then steps are taken to eliminate them.

What causes resource pollution?

There are many reasons that can cause water pollution. It is not always associated with human activities or industrial enterprises. Natural disasters that occur periodically in different areas can also disrupt environmental conditions. The most common reasons are considered to be:

• Domestic and industrial waste water. If they do not pass the system of purification from synthetic, chemical elements and organic substances, then, getting into water bodies, they are capable of provoking a water-environmental catastrophe.
• . This problem is not spoken about so often, so as not to provoke social tension. But the exhaust gases that enter the atmosphere after the emissions of road transport, industrial enterprises, along with rains, end up on the ground, polluting the environment.
• Solid waste, which can not only change the state of the biological environment in the reservoir, but also the flow itself. Often this leads to flooding of rivers and lakes, obstruction of the flow.
• Organic pollution associated with human activities, natural decomposition of dead animals, plants, etc.
• Industrial accidents and man-made disasters.
• Floods.
• Thermal pollution associated with the production of electricity and other energy. In some cases, water is heated up to 7 degrees, which causes the death of microorganisms, plants and fish, which require a different temperature regime.
• Avalanches, mudflows, etc.

In some cases, nature itself is able to clean up water resources over time. But the period of chemical reactions will be long. Most often, the death of inhabitants of reservoirs and pollution of fresh water cannot be prevented without human intervention.

The process of moving pollutants in water

If we are not talking about solid waste, then in all other cases, pollutants can exist:

• in a dissolved state;
• in a balanced state.

They may be droplets or small particles. Biocontaminants are observed in the form of live microorganisms or viruses.

If solid particles get into the water, they will not necessarily settle to the bottom. Depending on the current, storm events, they are able to rise to the surface. An additional factor is the composition of the water. In the sea, it is almost impossible for such particles to sink to the bottom. As a result of the current, they easily move over long distances.

Experts draw attention to the fact that due to the change in the direction of the current in coastal areas, the level of pollution is traditionally higher.

Regardless of the type of pollutant, it can enter the body of fish that live in a reservoir, or birds that are looking for food in the water. If this does not lead to the direct death of the creature, then it can affect the further food chain. There is a high probability that this is how water pollution poisons people and worsens their health.

The main results of the impact of pollution on the environment

Regardless of whether the pollutant enters the body of a person, fish, animal, a protective reaction is triggered. Some types of toxins can be neutralized by immune cells. In most cases, a living organism needs help in the form of treatment so that the processes do not become serious and do not lead to death.

Scientists determine, depending on the source of pollution and its influence, the following indicators of poisoning:

• Genotoxicity. Heavy metals and other trace elements are ways to damage and change the structure of DNA. As a result, serious problems are observed in the development of a living organism, the risk of diseases increases, etc.
• Carcinogenicity. The problems of oncology are closely related to what kind of water a person or animals consumes. The danger lies in the fact that a cell, having turned into a cancer cell, is able to quickly regenerate the rest in the body.
• neurotoxicity. Many metals, chemicals can affect the nervous system. Everyone knows the phenomenon of the release of whales, which is provoked by such pollution. The behavior of sea and river inhabitants becomes inadequate. They are not only able to kill themselves, but also begin to devour those who were previously uninteresting to them. Getting into the human body with water or food from such fish and animals, chemicals can provoke a slowdown in the reaction of the brain, destruction of nerve cells, etc.
• Violation of energy exchange. By acting on mitochondrial cells, pollutants are able to change the processes of energy production. As a result, the body ceases to carry out active actions. Lack of energy can cause death.
• reproductive insufficiency. If water pollution causes the death of living organisms not so often, then it can affect the state of health in 100 percent of cases. Scientists are especially concerned that their ability to reproduce a new generation is being lost. Solving this genetic problem is not easy. Requires artificial renewal of the aquatic environment.

How does water control and treatment work?

Realizing that pollution of fresh water endangers human existence, government agencies at the national and international levels create requirements for the implementation of enterprises and people's behavior. These frameworks are reflected in the documents regulating the procedures for water control and the operation of purification systems.

There are the following cleaning methods:

• Mechanical or primary. Its task is to prevent large objects from entering the reservoirs. To do this, special gratings and filters are installed on the pipes through which the drains go. It is required to clean the pipes in a timely manner, otherwise the blockage can cause an accident.
• Specialized. Designed to capture pollutants of a single type. For example, there are traps for fats, oil slicks, flocs, which are deposited with the help of coagulants.
• Chemical. It implies that wastewater will be reused in a closed cycle. Therefore, knowing their composition at the outlet, they select chemicals that are able to return water to its original state. Usually this is technical water, not drinking water.
• Tertiary cleaning. In order for water to be used in everyday life, agriculture, and in the food industry, its quality must be impeccable. To do this, it is treated with special compounds or powders that are capable of retaining heavy metals, harmful microorganisms and other substances in the process of multi-stage filtration.

In everyday life, more and more people are trying to install powerful filters that eliminate pollution caused by old communications and pipes.

Diseases that dirty water can provoke

Until it became clear that pathogens and bacteria can enter the body with water, humanity was faced with. After all, epidemics observed periodically in a particular country claimed the lives of hundreds of thousands of people.

The most common diseases that bad water can lead to include:

• cholera;
• enterovirus;
• giardiasis;
• schistosomiasis;
• amoebiasis;
• congenital deformities;
• mental anomalies;
• intestinal disorders;
• gastritis;
• skin lesions;
• mucous burns;
• oncological diseases;
• decrease in reproductive function;
• endocrine disorders.

The purchase of bottled water and the installation of filters is a means of preventing diseases. Some use silver items, which also partially disinfect the water.

Water pollution has the power to change the planet and make the quality of life completely different. That is why the issue of water conservation is constantly raised by environmental organizations and research centers. This makes it possible to draw the attention of enterprises, the public, and government agencies to existing problems and stimulate the start of active actions to prevent a catastrophe.