The main pollution of the world's oceans. Pollution of the oceans is one of the most acute environmental problems of our time.

The World Ocean, as it is customary to call the totality of all the seas and oceans of our planet, occupies over 70% of the surface of our planet, as a result of which it has a huge impact on all processes occurring on Earth. Therefore, the problem of increasing every year ocean pollution is one of the main problems facing humanity today.

How do humans pollute the oceans?

With the birth of mankind began the oceans. And if in the early stages of the development of civilization this ocean pollution was not catastrophic and was even somewhat useful (organic waste stimulated the growth of fish and underwater plants), then in the last two centuries, with the development of the chemical and especially the oil industry, this pollution begins to take on a threatening character and, if protective measures are not taken, can lead to the death of all life in the seas and oceans, and then, possibly, on land.

Oil and oil products

The most common pollutants of the World Ocean, entering the water as a result of leaks during oil production by, emergency situations during its transportation by tankers, and as a result of industrial and domestic waste discharges into freshwater reservoirs, from where it also enters the World Ocean with river water.

Another source of pollution of the seas and oceans is the widespread practice of washing the holds of tankers with sea water. As a result of the irresponsible actions of the captains of such ships, more than 20 million barrels of oil were dumped into the World Ocean in previous years. True, in recent years, thanks to the development of satellite tracking systems, most of these cases no longer go unpunished and the volume of this type of ocean pollution is decreasing.

Oil and oil products are dangerous because, despite their organic origin, these substances are practically not processed by ocean microorganisms, they form a film on the surface, which, by changing the composition of the spectrum of sunlight penetrating into the water column and hindering the access of oxygen, significantly changes the conditions for the existence of ocean plants and animals and leads to their mass death. The situation is aggravated by the stability of this film, which can only be removed by mechanical means.

Wastewater

Appearing with the advent of human civilization, sewage at first even had a positive stimulating effect on seaweed and fish, but with the transformation of this source of pollution of the oceans into powerful stinking streams escaping from the sewers of modern cities. To simply approach these modern cesspools, you will have to at least buy a respirator, and even better a gas mask. And all these products of human civilization rush either directly into the seas and oceans, or get there with the flow of rivers, leaving behind real underwater deserts dotted with organic remains.

The problem of sewage pollution is most relevant for coastal waters and inland seas. Thus, studies conducted in the North Sea showed that about 65% of the pollution found in it was brought by rivers. The recent efforts by developed countries to neutralize and liquefy wastewater have brought some effect, but so far it is clearly not enough, coordinated actions are needed from all countries of the world, especially China and India and other Asian countries, where it is considered in the order of things ...

Garbage patches in the oceans

The growth in the consumption of plastic products in recent decades has created a unique and dangerous phenomenon in the oceans, called "garbage patches". These are huge accumulations of pieces of plastic waste, formed as a result of the dumping of garbage from the coastal zones of the continents and from ocean liners, located in the form of huge spots on the surface of the ocean. To date, five giant garbage patches are known - two each in the Pacific and Atlantic oceans and one in the Indian.

Plastic particles floating on the surface, as well as an oil film, change the passage of sunlight, in addition, they often enter the stomach of marine animals and birds along with water, causing mass death of the latter. According to scientists, marine waste in the Pacific causes the death of more than a million seabirds and more than 100,000 marine animals every year.

The largest garbage island is located in the center of the Pacific Ocean, its rapid growth is due to the eddies of underwater ocean currents. The area of the Great Pacific Garbage Patch currently exceeds one million square kilometers. Environmental enthusiasts have created several public organizations to combat ocean pollution with plastic waste, but governments have so far managed to “not notice” the problem - after all, the garbage patch is not visible from the satellite, the plastic is transparent.

Protection of the World Ocean

That is why it is truly vital to protect the seas and oceans from harmful human activities. Many outstanding scientists have devoted themselves to this urgent task, important decisions are made at the government level every year, and I would like to hope that humanity will be able to stop the dangerous process of ocean water pollution and enjoy the blue expanses of the Earth for many years to come.

1. Features of the behavior of pollutants in the ocean

2. Anthropogenic ecology of the ocean - a new scientific direction in oceanology

3. The concept of assimilation capacity

4. Conclusions from the assessment of the assimilation capacity of the marine ecosystem by pollutants on the example of the Baltic Sea

1 Features of the behavior of pollutants in the ocean. Recent decades have been marked by increased anthropogenic impacts on marine ecosystems as a result of pollution of the seas and oceans. The spread of many pollutants has become local, regional and even global scope. Therefore, the pollution of the seas, oceans and their biota has become the most important international problem, and the need to protect the marine environment from pollution is dictated by the requirements rational use natural resources.

Marine pollution is understood as: “the introduction by man, directly or indirectly, of substances or energy into the marine environment (including estuaries), entailing such harmful consequences as damage to living resources, danger to human health, interference with marine activities, including fishing, deterioration sea water and diminishing its beneficial properties. This list includes substances with toxic properties, discharges of heated waters (thermal pollution), pathogenic microbes, solid wastes, suspended solids, nutrients and some other forms of anthropogenic impacts.

The most urgent problem in our time has become the problem of chemical pollution of the ocean.

The sources of pollution of the ocean and seas include the following:

Discharge of industrial and economic waters directly into the sea or with river runoff;

Intake from land of various substances used in agriculture and forestry;

Intentional dumping of pollutants at sea; leakage of various substances during ship operations;

Accidental releases from ships or subsea pipelines;

Development of minerals on the seabed;

Transport of pollutants through the atmosphere.

The list of pollutants received by the ocean is extremely extensive. All of them differ in the degree of toxicity and the scale of distribution - from coastal (local) to global.

More and more pollutants are being found in the oceans. The most dangerous for organisms organochlorine compounds, polyaromatic hydrocarbons and some others are becoming globally widespread. They have a high bioaccumulative capacity, a sharp toxic and carcinogenic effect.

The steady increase in the total impact of many pollution sources leads to progressive eutrophication of coastal marine zones and microbiological water pollution, which significantly complicates the use of water for various human needs.

Oil and oil products. Oil is a viscous oily liquid, usually dark brown in color and with low fluorescence. Oil consists mainly of saturated aliphatic and hydroaromatic hydrocarbons (from C 5 to C 70) and contains 80-85% C, 10-14% H, 0.01-7% S, 0.01% N and 0-7% O 2.

The main components of oil - hydrocarbons (up to 98%) - are divided into four classes.

1. Paraffins (alkanes) (up to 90% of the total composition of oil) are stable saturated compounds C n H 2n-2, the molecules of which are expressed by a straight or branched (isoalkanes) chain of carbon atoms. Paraffins include the gases methane, ethane, propane and others, compounds with 5-17 carbon atoms are liquids, and those with a large number of carbon atoms are solids. Light paraffins have maximum volatility and solubility in water.

2. Cycloparaffins. (naphthenes)-saturated cyclic compounds C n H 2 n with 5-6 carbon atoms in the ring (30-60% of the total oil composition). In addition to cyclopentane and cyclohexane, bicyclic and polycyclic naphthenes are found in oil. These compounds are very stable and difficult to biodegrade.

3. Aromatic hydrocarbons (20-40% of the total composition of oil) - unsaturated cyclic compounds of the benzene series, containing 6 carbon atoms in the ring less than the corresponding naphthenes. The carbon atoms in these compounds can also be replaced by alkyl groups. Oil contains volatile compounds with a molecule in the form of a single ring (benzene, toluene, xylene), then bicyclic (naphthalene), tricyclic (anthracene, phenanthrene) and polycyclic (for example, pyrene with 4 rings) hydrocarbons.

4. Olephips (alkenes) (up to 10% of the total composition of oil) are unsaturated non-cyclic compounds with one or two hydrogen atoms at each carbon atom in a molecule that has a straight or branched chain.

Depending on the field, oils differ significantly in their composition. Thus, Pennsylvania and Kuwaiti oils are classified as paraffinic, Baku and California - mainly naphthenic, the rest of the oils - intermediate types.

Oil also contains sulfur-containing compounds (up to 7% sulfur), fatty acids (up to 5% oxygen), nitrogen compounds (up to 1% nitrogen) and some organometallic derivatives (with vanadium, cobalt and nickel).

Quantitative analysis and identification of oil products in the marine environment present significant difficulties not only because of their multicomponent nature and differences in the forms of existence, but also due to the natural background of hydrocarbons of natural and biogenic origin. For example, about 90% of low molecular weight hydrocarbons such as ethylene dissolved in the surface waters of the ocean is associated with the metabolic activity of organisms and the decay of their residues. However, in areas of intense pollution, the level of content of such hydrocarbons increases by 4-5 orders of magnitude.

Hydrocarbons of biogenic and petroleum origin, according to experimental studies, have a number of differences.

1. Oil is a more complex mixture of hydrocarbons with a wide range of structures and relative molecular weights.

2. Oil contains several homologous series, in which neighboring members usually have equal concentrations. For example, in the C 12 -C 22 series of alkanes, the ratio of even and odd members is equal to one, while biogenic hydrocarbons in the same series contain predominantly odd members.

3. Oil contains a wider range of cycloalkanes and aromatics. Many compounds such as mono-, di-, tri- and tetramethylbenzenes are not found in marine organisms.

4. Oil contains numerous naphtheno-aromatic hydrocarbons, various heterocompounds (containing sulfur, nitrogen, oxygen, metal ions), heavy asphalt-like substances - all of them are practically absent in organisms.

Oil and oil products are the most common pollutants in the oceans.

The routes of entry and forms of existence of petroleum hydrocarbons are diverse (dissolved, emulsified, filmy, solid). M. P. Nesterova (1984) notes the following ways of admission:

discharges in ports and near-port water areas, including losses when loading bunkers of tankers (17%~);

Discharge of industrial waste and sewage (10%);

Storm drains (5%);

Disasters of ships and drilling rigs at sea (6%);

Offshore drilling (1%);

Atmospheric fallout (10%)",

Removal by river runoff in all variety of forms (28%).

Discharges into the sea of washing, ballast and bilge water from ships (23%);

The greatest losses of oil are associated with its transportation from production areas. Emergencies, discharge of washing and ballast water overboard by tankers - all this leads to the presence of permanent pollution fields along sea routes.

The property of oils is their fluorescence under ultraviolet irradiation. The maximum fluorescence intensity is observed in the wavelength range 440-483 nm.

The difference in the optical characteristics of oil films and sea water allows remote detection and evaluation of oil pollution on the sea surface in the ultraviolet, visible and infrared parts of the spectrum. For this, passive and active methods. Large masses of oil from land enter the seas along rivers, with domestic and storm drains.

The fate of oil spilled into the sea is determined by the sum of the following processes: evaporation, emulsification, dissolution, oxidation, formation of oil aggregates, sedimentation and biodegradation.

Getting into the marine environment, oil first spreads in the form of a surface film, forming slicks of various thicknesses. By the color of the film, you can approximately estimate its thickness. The oil film changes the intensity and spectral composition of the light penetrating into the water mass. The light transmission of thin films of crude oil is 1-10% (280 nm), 60-70% (400 nm). An oil film with a thickness of 30-40 microns completely absorbs infrared radiation.

In the early days of oil slicks, the evaporation of hydrocarbons was of great importance. According to observations, up to 25% of light oil fractions evaporate in 12 hours; at a water temperature of 15 °C, all hydrocarbons up to C 15 evaporate in 10 days (Nesterova, Nemirovskaya, 1985).

All hydrocarbons have a low solubility in water, which decreases with increasing number of carbon atoms in the molecule. About 10 mg of compounds with C 6, 1 mg of compounds with C 8 and 0.01 mg of compounds with C 12 are dissolved in 1 liter of distilled water. For example, when average temperature sea water, the solubility of benzene is 820 µg/l, toluene - 470, pentane - 360, hexane - 138 and heptane - 52 µg/l. Soluble components, the content of which in crude oil does not exceed 0.01%, are the most toxic for aquatic organisms. They also include substances such as benzo(a)pyrene.

When mixed with water, oil forms two types of emulsions: direct "oil in water" and reverse "water in oil". Direct emulsions, composed of oil droplets with a diameter of up to 0.5 microns, are less stable and are especially characteristic of oils containing surfactants. After removal of volatile and soluble fractions, residual oil often forms viscous inverse emulsions, which are stabilized by high-molecular compounds such as resins and asphaltenes and contain 50-80% water (“chocolate mousse”). Under the influence of abiotic processes, the viscosity of the "mousse" increases and it begins to stick together into aggregates - oil lumps ranging in size from 1 mm to 10 cm (usually 1-20 mm). The aggregates are a mixture of high molecular weight hydrocarbons, resins and asphaltenes. Oil losses for the formation of aggregates are 5-10%. Highly viscous structured formations - "chocolate mousse" and oil lumps - can remain on the sea surface for a long time, be carried by currents, be thrown ashore and settle to the bottom. Oil lumps are often populated by periphyton (blue-green and diatoms, barnacles and other invertebrates).

Pesticides constitute an extensive group of artificially created substances used to control pests and plant diseases. Depending on the intended purpose, pesticides are divided into the following groups: insecticides - to combat harmful insects, fungicides and bactericides - to combat fungal and bacterial plant diseases, herbicides - against weeds, etc. According to economists' calculations, each ruble spent on the chemical protection of plants from pests and diseases, ensures the preservation of the crop and its quality in the cultivation of cereals and vegetable crops an average of 10 rubles, technical and fruit - up to 30 rubles. At the same time, environmental studies have established that pesticides, destroying crop pests, cause great harm to many beneficial organisms and undermine the health of natural biocenoses. Agriculture has long faced the challenge of shifting from chemical (polluting) to biological (environmentally friendly) methods of pest control.

Currently, more than 5 million tons of pesticides enter the world market annually. About 1.5 million tons of these substances have already entered the terrestrial and marine ecosystems by aeolian or aquatic routes. The industrial production of pesticides is accompanied by the appearance a large number by-products polluting wastewater.

In the aquatic environment, representatives of insecticides, fungicides and herbicides are more common than others.

Synthesized insecticides are divided into three main groups: organochlorine, organophosphorus and carbamates.

Organochlorine insecticides are obtained by chlorination of aromatic or heterocyclic liquid hydrocarbons. These include DDT (dichlorodiphenyltrichloroethane) and its derivatives, in the molecules of which the stability of aliphatic and aromatic groups increases in the joint presence, various chlorinated derivatives of cyclodiene (eldrin, dil-drin, heptachlor, etc.), as well as numerous isomers of hexachlorocyclohexane (in -HCCH), of which lindane is the most dangerous. These substances have a half-life of up to several decades and are very resistant to biodegradation.

In the aquatic environment, polychlorinated biphenyls (PCBs) are often found - DDT derivatives without an aliphatic part, numbering 210 theoretical homologues and isomers.

Over the past 40 years, more than 1.2 million tons of PCBs have been used in the production of plastics, dyes, transformers, capacitors, etc. Polychlorinated biphenyls enter the environment as a result of industrial wastewater discharges and solid waste incineration in landfills. The latter source delivers PCBs to the atmosphere, from where they fall out with atmospheric precipitation in all areas the globe. So, in snow samples taken in Antarctica, the content of PCBs was 0.03-1.2 ng/l.

Organophosphate pesticides are esters of various alcohols of phosphoric acid or one of its derivatives, thiophosphoric. This group includes modern insecticides with a characteristic selectivity of action in relation to insects. Most organophosphates are subject to fairly rapid (within a month) biochemical degradation in soil and water. More than 50,000 active substances have been synthesized, of which parathion, malathion, phosalong, and dursban are especially famous.

Carbamates are, as a rule, esters of n-metacarbamic acid. Most of them also have a selective action.

As fungicides used to combat fungal diseases of plants, copper salts and some mineral sulfur compounds were previously used. Then, organomercury substances such as chlorinated methylmercury were widely used, which, due to its extreme toxicity to animals, was replaced by methoxyethylmercury and phenylmercury acetates.

The group of herbicides includes derivatives of phenoxyacetic acid, which have a strong physiological effect. Triazines (for example, simazine) and substituted ureas (monuron, diuron, pichloram) constitute another group of herbicides, quite well soluble in water and stable in soils. Pichloram is the strongest of all herbicides. For the complete destruction of some plant species, only 0.06 kg of this substance per 1 ha is required.

DDT and its metabolites, PCBs, HCH, deldrin, tetrachlorophenol and others are constantly found in the marine environment.

Synthetic surfactants. Detergents (surfactants) belong to an extensive group of substances that lower the surface tension of water. They are part of synthetic detergents (CMC), widely used in everyday life and industry. Together with wastewater, surfactants enter the continental surface waters and the marine environment. Synthetic detergents contain sodium polyphosphates, in which detergents are dissolved, as well as a number of additional ingredients that are toxic to aquatic organisms: fragrances, bleaching agents (persulphates, perborates), soda ash, carboxymethyl cellulose, sodium silicates and others.

The molecules of all surfactants consist of hydrophilic and hydrophobic parts. The hydrophilic part is carboxyl (COO -), sulfate (OSO 3 -) and sulfonate (SO 3 -) groups, as well as accumulations of residues with groups -CH 2 -CH 2 -O-CH 2 -CH 2 - or groups containing nitrogen and phosphorus. The hydrophobic part usually consists of a straight line, including 10-18 carbon atoms, or a branched paraffin chain, from a benzene or naphthalene ring with alkyl radicals.

Depending on the nature and structure of the hydrophilic part of the surfactant molecules, they are divided into anionic (the organic ion is negatively charged), cationic (the organic ion is positively charged), amphoteric (displaying cationic properties in an acidic solution, and anionic in an alkaline solution) and nonionic. The latter do not form ions in water. Their solubility is due to functional groups that have a strong affinity for water and the formation of a hydrogen bond between water molecules and oxygen atoms included in the polyethylene glycol radical of the surfactant.

The most common among the surfactants are anionic substances. They account for more than 50% of all surfactants produced in the world. The most common are alkylarylsulfonates (sulfonols) and alkyl sulfates. Sulfonol molecules contain an aromatic ring, the hydrogen atoms of which are replaced by one or more alkyl groups, and a sulfuric acid residue as a solvating group. Numerous alkylbenzene sulfonates and alkylnaphthalenesulfonates are often used in the manufacture of various household and industrial CMCs.

The presence of surfactants in industrial wastewater is associated with their use in such processes as flotation beneficiation of ores, separation of chemical technology products, production of polymers, improvement of conditions for drilling oil and gas wells, and equipment corrosion control.

In agriculture, surfactants are used as part of pesticides. With the help of surfactants, liquid and powdered toxic substances that are insoluble in water, but soluble in organic solvents, are emulsified, and many surfactants themselves have insecticidal and herbicidal properties.

Carcinogenic substances- these are chemically homogeneous compounds that exhibit transforming activity and are capable of causing carcinogenic, teratogenic (violation of embryonic development processes) or mutagenic changes in organisms. Depending on the conditions of exposure, they can lead to growth inhibition, accelerated aging, toxicogenesis, impaired individual development and changes in the gene pool of organisms. Substances with carcinogenic properties include chlorinated aliphatic hydrocarbons with a short chain of carbon atoms in the molecule, vinyl chloride, pesticides and, especially, polycyclic aromatic hydrocarbons (PAHs). The latter are high molecular weight organic compounds, in the molecules of which the benzene ring is the main element of the structure. Numerous unsubstituted PAHs contain from 3 to 7 benzene rings in the molecule, interconnected in various ways. There are also a large number of polycyclic structures containing a functional group either in the benzene ring or in the side chain. This halogen-, amino-, sulfo-, nitro derivatives, as well as alcohols, aldehydes, esters, ketones, acids, quinones and other aromatic compounds.

The solubility of PAHs in water is low and decreases with increasing molecular weight: from 16 100 µg/l (acenaphthylene) to 0.11 µg/l (3,4-benzpyrene). The presence of salts in water has practically no effect on the solubility of PAHs. However, in the presence of benzene, oil, oil products, detergents, and other organic substances, the solubility of PAHs sharply increases. Of the group of unsubstituted PAHs, 3,4-benzpyrene (BP) is the best known and widespread under natural conditions.

Natural and anthropogenic processes can serve as sources of PAHs in the environment. The concentration of BP in volcanic ash is 0.3-0.9 µg/kg. This means that 1.2-24 tons of BP per year can enter the environment with ash. Therefore, the maximum amount of PAHs in modern bottom sediments of the World Ocean (more than 100 µg/kg of dry matter mass) was found in tectonically active zones subject to deep thermal action.

Some marine plants and animals are reported to be able to synthesize PAHs. In algae and sea grasses near the western coast of Central America, the content of BP reaches 0.44 µg/g, and in some crustaceans in the Arctic, 0.23 µg/g. Anaerobic bacteria produce up to 8.0 μg of BP from 1 g of plankton lipid extracts. On the other hand, there are special types of marine and soil bacteria that decompose hydrocarbons, including PAHs.

According to L. M. Shabad (1973) and A. P. Ilnitsky (1975), the background concentration of BP created as a result of the synthesis of BP by plant organisms and volcanic activity is: in soils 5-10 µg/kg (dry matter), in plants 1-5 µg/kg, in freshwater reservoirs 0.0001 µg/l. Accordingly, gradations of the degree of pollution of environmental objects are also derived (Table 1.5).

The main anthropogenic sources of PAHs in the environment are the pyrolysis of organic substances during the combustion of various materials, wood, and fuel. The pyrolytic formation of PAHs occurs at a temperature of 650-900 °C and a lack of oxygen in the flame. The formation of BP was observed during the pyrolysis of wood with a maximum yield at 300–350°C (Dikun, 1970).

According to M. Suess (G976), the global emission of BP in the 70s was about 5000 tons per year, with 72% coming from industry and 27% from all types of open burning.

Heavy metals(mercury, lead, cadmium, zinc, copper, arsenic and others) are among the common and highly toxic pollutants. They are widely used in various industrial productions, therefore, despite the treatment measures, the content of heavy metal compounds in industrial wastewater is quite high. Large masses of these compounds enter the ocean through the atmosphere. Mercury, lead and cadmium are the most dangerous for marine biocenoses.

Mercury is transported to the ocean with continental runoff and through the atmosphere. During the weathering of sedimentary and igneous rocks, 3.5 thousand tons of mercury are released annually. The composition of atmospheric dust contains about 12 thousand tons of mercury, and a significant part of anthropogenic origin. As a result of volcanic eruptions and atmospheric precipitation, 50 thousand tons of mercury annually enters the ocean surface, and 25-150 thousand tons during degassing of the lithosphere. About half of the annual industrial production of this metal (9-10 thousand tons / year) in various ways falls into the ocean. The content of mercury in coal and oil is on average 1 mg/kg; therefore, when burning fossil fuels, the World Ocean receives more than 2 thousand tons/year. The annual production of mercury exceeds 0.1% of its total content in the World Ocean, but the anthropogenic influx already exceeds the natural removal by rivers, which is typical for many metals.

In areas polluted by industrial wastewater, the concentration of mercury in solution and suspension is greatly increased. At the same time, some benthic bacteria convert chlorides into highly toxic (mono- and di-) methylmercury CH 3 Hg. Contamination of seafood has repeatedly led to mercury poisoning of the coastal population. By 1977, there were 2,800 victims of Minamata disease in Japan. The reason was the waste of enterprises for the production of vinyl chloride and acetaldehyde, in which mercury chloride was used as a catalyst. Insufficiently treated wastewater from enterprises entered the Minamata Bay.

Lead is a typical trace element found in all environmental components: in rocks, soils, natural waters, atmosphere, living organisms. Finally, lead is actively dissipated into the environment during human activities. These are emissions from industrial and domestic effluents, from smoke and dust from industrial enterprises, from exhaust gases from internal combustion engines.

According to V.V. Dobrovolsky (1987), the redistribution of lead masses between land and the World Ocean is as follows. C. river runoff at an average lead concentration in water of 1 μg / l into the ocean of water-soluble lead is carried out about 40 10 3 t / year, in the solid phase of river suspensions about 2800-10 3 t / year, in fine organic detritus - 10 10 3 t /year. Considering that in a narrow coastal strip more than 90% of river suspensions settle on the shelf and a significant part of water-soluble metal compounds are captured by iron oxide gels, then as a result, the ocean pelagial receives only about (200-300) 10 3 tons in the composition of fine suspensions and (25-30) 10 3 tons of dissolved compounds.

The migration flow of lead from the continents to the ocean goes not only with river runoff, but also through the atmosphere. With continental dust, the ocean receives (20-30)-10 3 tons of lead per year. Its entry to the ocean surface with liquid atmospheric precipitation is estimated at (400-2500) 10 3 t/year at a concentration in rainwater of 1-6 µg/l. The sources of lead entering the atmosphere are volcanic emissions (15-30 t/year in the composition of pelitic eruption products and 4 10 3 t/year in submicron particles), volatile organic compounds from vegetation (250-300 t/year), combustion products from fires ((6-7) 10 3 t/year) and modern industry. Lead production increased from 20-10 3 t/year in early XIX in. up to 3500 10 3 t/year by the beginning of the 80s of the XX century. Modern release of lead into the environment with industrial and household waste is estimated at (100-400) 10 3 t/year.

Cadmium, whose world production in the 1970s reached 15 10 3 tons/year, also enters the ocean with river runoff and through the atmosphere. The volume of atmospheric removal of cadmium, according to various estimates, is (1.7-8.6) 10 3 t/year.

Discharge of waste into the sea for the purpose of disposal (dumping). Many countries with access to the sea undertake marine disposal of various materials and substances, in particular soil excavated during dredging, drill cuttings, industrial waste, construction debris, solid waste, explosives and chemicals, radioactive waste, etc. Volume landfills is about 10% of the total mass of pollutants entering the oceans. So, from 1976 to 1980, more than 150 million tons of various wastes were dumped annually for the purpose of burial, which defines the concept of "dumping".

The basis for dumping in the sea is the ability of the marine environment to process a large amount of organic and inorganic substances without much damage to water quality. However, this ability is not unlimited. Therefore, dumping is considered as a forced measure, a temporary tribute to the imperfection of technology by society. Hence, the development and scientific substantiation of ways to regulate waste discharges into the sea are of particular importance.

Industrial sludge contains a variety of organic substances and heavy metal compounds. Household garbage contains on average (on a dry matter basis) 32-40% organic matter, 0.56% nitrogen, 0.44% phosphorus, 0.155% zinc, 0.085% lead, 0.001% cadmium, 0.001 mercury. Sludge from municipal wastewater treatment plants contains (per dry matter weight) up to. 12% humic substances, up to 3% total nitrogen, up to 3.8% phosphates, 9-13% fats, 7-10% carbohydrates and are contaminated with heavy metals. Bottom grab materials have a similar composition.

During the discharge, when the material passes through the water column, part of the pollutants goes into solution, changing the quality of the water, while the other part is sorbed by suspended particles and goes into bottom sediments. At the same time, the turbidity of the water increases. The presence of organic substances often leads to the rapid consumption of oxygen in water and often to its complete disappearance, the dissolution of suspensions, the accumulation of metals in dissolved form, and the appearance of hydrogen sulfide. The presence of a large amount of organic matter creates a stable reducing environment in the soil, in which a special type of interstitial water appears, containing hydrogen sulfide, ammonia, and metal ions in reduced form. In this case, the reduction of sulfates and nitrates, phosphates are released.

Neuston, pelagic and benthos organisms are affected to varying degrees by the discharged materials. In the case of the formation of surface films containing petroleum hydrocarbons and surfactants, gas exchange at the air-water interface is disrupted. This leads to the death of invertebrate larvae, fish larvae and fry, and causes an increase in the number of oil-oxidizing and pathogenic microorganisms. The presence of a polluting suspension in the water worsens the conditions of nutrition, respiration and metabolism of hydrobionts, reduces the growth rate, and inhibits the puberty of planktonic crustaceans. Pollutants entering the solution can accumulate in the tissues and organs of hydrobionts and have a toxic effect on them. The dumping of dumping materials to the bottom and prolonged increased turbidity of the bottom water lead to filling and death from suffocation of attached and inactive forms of benthos. In surviving fish, mollusks and crustaceans, the growth rate is reduced due to the deterioration of feeding and breathing conditions. The species composition of the benthic community often changes.

When organizing a system for controlling waste discharges into the sea, the definition of dumping areas, taking into account the properties of materials and the characteristics of the marine environment, is of decisive importance. The necessary criteria for solving the problem are contained in the "Convention for the Prevention of Marine Pollution by Dumping of Wastes and Other Materials" (London Convention on Dumping, 1972). The main requirements of the Convention are as follows.

1. Assessment of the quantity, condition and properties (physical, chemical, biochemical, biological) of discharged materials, their toxicity, stability, tendency to accumulation and biotransformation in the aquatic environment and marine organisms. Using the possibilities of neutralization, neutralization and recycling of waste.

2. Selection of areas of discharge, taking into account the requirements of maximum dilution of substances, their minimum spread beyond the discharge, a favorable combination of hydrological and hydrophysical conditions.

3. Ensuring remoteness of discharge areas from fish feeding and spawning areas, from habitats of rare and sensitive species of hydrobionts, from recreation and economic use areas.

Technogenic radionuclides. The ocean is characterized by natural radioactivity due to the presence in it of 40 K, 87 Rb, 3 H, 14 C, as well as radionuclides of the uranium and thorium series. More than 90% of the natural radioactivity of ocean water is 40 K, which is 18.5-10 21 Bq. The unit of activity in the SI system is the becquerel (Bq), equal to the activity of an isotope in which 1 decay event occurs in 1 s. Previously, the off-system unit of radioactivity, curie (Ci), was widely used, corresponding to the activity of an isotope in which 3.7-10 10 decay events occur in 1 s.

Radioactive substances of technogenic origin, mainly fission products of uranium and plutonium, began to enter the ocean in large quantities after 1945, i.e., from the beginning of tests nuclear weapons and the wide development of the industrial production of fissile materials and radioactive nuclides. Three groups of sources are identified: 1) testing of nuclear weapons, 2) dumping of radioactive waste, 3) accidents of ships with nuclear engines and accidents associated with the use, transportation and production of radionuclides.

Many radioactive isotopes with a short half-life, although found in water and marine organisms after an explosion, are almost never found in global radioactive fallout. Here, first of all, 90 Sr and 137 Cs are present with a half-life of about 30 years. The most dangerous radionuclide from the unreacted remains of nuclear charges is 239 Pu (T 1/2 = 24.4-10 3 years), which is very poisonous as a chemical substance. As fission products 90 Sr and 137 Cs decay, it becomes the main contaminant. By the time of the moratorium on atmospheric tests of nuclear weapons (1963), the activity of 239 Pu in the environment was 2.5-10 16 Bq.

A separate group of radionuclides is formed by 3 H, 24 Na, 65 Zn, 59 Fe, 14 C, 31 Si, 35 S, 45 Ca, 54 Mn, 57.60 Co and others arising from the interaction of neutrons with structural elements and the environment. The main products of nuclear reactions with neutrons in the marine environment are the radioisotopes of sodium, potassium, phosphorus, chlorine, bromine, calcium, manganese, sulfur, and zinc, which originate from elements dissolved in sea water. This is induced activity.

Most of the radionuclides that enter the marine environment have analogs that are constantly present in water, such as 239 Pu, 239 Np, 99 T C) transplutonium are not characteristic of the composition of sea water, and the living matter of the ocean must adapt to them again.

As a result of the processing of nuclear fuel, a significant amount of radioactive waste appears in liquid, solid and gaseous forms. The bulk of the waste is radioactive solutions. Given the high cost of processing and storing concentrates in special storage facilities, some countries choose to dump waste into the ocean with river runoff or dump it in concrete blocks on the bottom of deep ocean trenches. For the radioactive isotopes Ar, Xe, Em and T, reliable methods of concentration have not yet been developed, so they can enter the oceans with rain and sewage.

During the operation of nuclear power plants on surface and underwater vessels, of which there are already several hundred, about 3.7-10 16 Bq with ion-exchange resins, about 18.5-10 13 Bq with liquid waste and 12.6-10 13 Bq due to leaks. Emergencies also make a significant contribution to ocean radioactivity. To date, the amount of radioactivity introduced into the ocean by man does not exceed 5.5-10 19 Bq, which is still small compared to the natural level (18.5-10 21 Bq). However, the concentration and unevenness of radionuclide fallout creates a serious danger of radioactive contamination of water and hydrobionts in certain areas of the ocean.

2 Anthropogenic ocean ecology–new scientific direction in oceanology. As a result anthropogenic impact additional environmental factors appear in the ocean, contributing to the negative evolution of marine ecosystems. The discovery of these factors stimulated the development of extensive fundamental research in the World Ocean and the emergence of new scientific directions. Among them is the anthropogenic ecology of the ocean. This new direction is intended to study the mechanisms of response of organisms to anthropogenic impacts at the level of a cell, organism, population, biocenosis, ecosystem, as well as to study the features of interactions between living organisms and the environment in changed conditions.

The object of study of the anthropogenic ecology of the ocean is the change in the ecological characteristics of the ocean, primarily those changes that are important for the ecological assessment of the state of the biosphere as a whole. These studies are based on complex analysis the state of marine ecosystems, taking into account geographic zoning and the degree of anthropogenic impact.

The anthropogenic ecology of the ocean uses the following methods of analysis for its purposes: genetic (assessment of carcinogenic and mutagenic hazards), cytological (study of the cellular structure of marine organisms in normal and pathological conditions), microbiological (study of the adaptation of microorganisms to toxic pollutants), ecological (knowledge of the patterns of formation and development of populations and biocenoses in specific habitat conditions in order to predict their state in changing environmental conditions), ecological and toxicological (study of the response of marine organisms to the effects of pollution and determination of critical concentrations of pollutants), chemical (study of the entire complex of natural and anthropogenic chemicals in marine environment).

The main task of the anthropogenic ecology of the ocean is to develop the scientific basis for determining critical levels pollutants in marine ecosystems, assessing the assimilation capacity of marine ecosystems, standardizing anthropogenic impacts on the World Ocean, as well as in creating mathematical models ecological processes for predicting ecological situations in the ocean.

Knowledge about the most important ecological phenomena in the ocean (such as production-destruction processes, the passage of biogeochemical cycles of pollutants, etc.) is limited by a lack of information. This makes it difficult to predict the ecological situation in the ocean and the implementation of environmental protection measures. At present, of particular importance is the implementation of ecological monitoring of the ocean, the strategy of which is focused on long-term observations in certain areas of the ocean with the aim of creating a data bank covering global changes in ocean ecosystems.

3 The concept of assimilation capacity. According to the definition of Yu. A. Israel and A. V. Tsyban (1983, 1985), the assimilation capacity of the marine ecosystem A i for this pollutant i(or the sum of pollutants) and for the m-th ecosystem is the maximum dynamic capacity of such a quantity of pollutants (in terms of the entire zone or volume unit of the marine ecosystem), which can be accumulated, destroyed, transformed per unit of time (by biological or chemical transformations ) and removed due to the processes of sedimentation, diffusion or any other transfer outside the volume of the ecosystem without disturbing its normal functioning.

The total removal (A i) of a pollutant from a marine ecosystem can be written as

where K i is the safety factor reflecting the environmental conditions of the pollution process in different zones of the marine ecosystem; τ i - residence time of the pollutant in the marine ecosystem.

This condition is met at , where C 0 i is the critical concentration of the pollutant in sea water. Hence, the assimilation capacity can be estimated by formula (1) at ;.

All quantities included in right side Equations (1) can be directly measured using data obtained in the course of long-term integrated studies of the state of the marine ecosystem. At the same time, the sequence of determining the assimilation capacity of a marine ecosystem for specific pollutants includes three main stages: 1) calculating the balances of the mass and lifetime of pollutants in the ecosystem, 2) analyzing the biotic balance in the ecosystem, and 3) assessing the critical concentrations of the impact of pollutants (or environmental MPCs). ) on the functioning of the biota.

To address the issues of environmental regulation of anthropogenic impacts on marine ecosystems, the calculation of the assimilation capacity is the most representative, since it takes into account the assimilation capacity, the maximum permissible environmental load (MPEL) of the pollutant reservoir is calculated quite simply. So, in the stationary mode of pollution of the reservoir, PDEN will be equal to the assimilation capacity.

4 Conclusions from the assessment of the assimilation capacity of the marine ecosystem by pollutants on the example of the Baltic Sea. Using the example of the Baltic Sea, the values of assimilation capacity for a number of toxic metals (Zn, Сu, Pb, Cd, Hg) and organic substances (PCBs and BP) were calculated (Izrael, Tsyban, Venttsel, Shigaev, 1988).

The average concentrations of toxic metals in sea water turned out to be one or two orders of magnitude lower than their threshold doses, while the concentrations of PCBs and BP were only an order of magnitude lower. Hence, the safety factors for PCBs and BP turned out to be lower than for metals. At the first stage of the work, the authors of the calculation, using the materials of long-term ecological studies in the Baltic Sea and literary sources, determined the concentrations of pollutants in the components of the ecosystem, the rates of biosedimentation, the fluxes of substances at the boundaries of the ecosystem, and the activity of microbial destruction of organic substances. All this made it possible to draw up balances and calculate the “lifetime” of the considered substances in the ecosystem. The "lifetime" of metals in the Baltic ecosystem turned out to be quite short for lead, cadmium and mercury, somewhat longer for zinc, and maximum for copper. The "lifetime" of PCBs and benzo(a)pyrene is 35 and 20 years, which determines the need to introduce a system of genetic monitoring of the Baltic Sea.

At the second stage of research, it was shown that the most sensitive element of the biota to pollutants and changes in the ecological situation are planktonic microalgae, and therefore, the process of primary production of organic matter should be chosen as the “target” process. Therefore, the threshold doses of pollutants established for phytoplankton are applied here.

Estimates of the assimilation capacity of the zones of the open part of the Baltic Sea show that the existing runoff of zinc, cadmium and mercury, respectively, is 2, 20 and 15 times less than the minimum values of the assimilation capacity of the ecosystem for these metals and does not pose a direct danger to primary production. At the same time, the supply of copper and lead already exceeds their assimilation capacity, which requires the introduction of special measures to limit the flow. The current supply of BP has not yet reached the minimum value of the assimilation capacity, while PCBs exceed it. The latter points to the urgent need to further reduce PCB discharges into the Baltic Sea.

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1. Oil pollution of the oceans

World Ocean, a continuous water shell of the Earth, surrounding the land (continents and islands) and having a common salt composition. Takes about 71% earth's surface(in the northern hemisphere - 61%, in the southern - 81%). The average depth is 3795m, the maximum depth is 11022m. (Marian Trench in the Pacific Ocean), the volume of water is approximately 1370 million km3. The world ocean is divided into 4 parts: Pacific, Atlantic, Indian and Arctic oceans. Less than 20% of the total number of species of living organisms found so far on Earth lives in the oceans. The total biomass of the World Ocean is about 30 billion tons. dry organic matter. Even more revealing is this comparison: the oceans account for 98.5% of water and ice on Earth, while inland waters account for only 1.5%. While the average height of the continents is only 840m, the average depth of the World Ocean is 3795m.

Pollution of the waters of the World Ocean has taken catastrophic proportions over the past 10 years. This was largely facilitated by the widespread opinion about the unlimited possibilities of the waters of the World Ocean for self-purification. Many understood this to mean that any waste and garbage in any quantity in the waters of the ocean is subjected to biological processing without harmful consequences for the waters themselves.

Regardless of the type of pollution, whether it is pollution of the soil, atmosphere or water, everything ultimately comes down to pollution of the waters of the World Ocean, where all toxic substances eventually enter, turning the World Ocean into a “global garbage dump”.

There are the following sources of their discharge:

- in tankers, washing tanks and draining ballast water;

- in dry cargo ships, bilge water discharge, leakage from tanks or pump rooms;

- spillage during loading and unloading;

- accidental outflow during collision of ships;

- in underwater production, the appearance is not from the surface, but from the bottom.

Oil is a viscous oily liquid that is dark brown in color and has low fluorescence. Oil consists mainly of saturated aliphatic and hydroaromatic hydrocarbons. The main components of oil - hydrocarbons (up to 98%) - are divided into 4 classes:

1. Paraffins (alkenes) - (up to 90% of the total composition) - stable substances, the molecules of which are expressed by a straight and branched chain of carbon atoms. Light paraffins have maximum volatility and solubility in water.

2. Cycloparaffins - (30 - 60% of the total composition) saturated cyclic compounds with 5-6 carbon atoms in the ring. In addition to cyclopentane and cyclohexane, bicyclic and polycyclic compounds of this group are found in oil. These compounds are very stable and difficult to biodegrade.

3. Aromatic hydrocarbons - (20 - 40% of the total composition) - unsaturated cyclic compounds of the benzene series, containing 6 carbon atoms in the ring less than cycloparaffins. Oil contains volatile compounds with a molecule in the form of a single ring (benzene, toluene, xylene), then bicyclic (naphthalene), semicyclic (pyrene).

4. Olefins (alkenes) - (up to 10% of the total composition) - unsaturated non-cyclic compounds with one or two hydrogen atoms at each carbon atom in a molecule that has a straight or branched chain.

Oil and oil products are the most common pollutants in the oceans. Getting into the marine environment, oil first spreads in the form of a film, forming layers of various thicknesses. By the color of the film, you can determine its thickness:

The oil film changes the composition of the spectrum and the intensity of light penetration into the water. The light transmission of thin films of crude oil is 11-10% (280nm), 60-70% (400nm). A film with a thickness of 30-40 microns completely absorbs infrared radiation. When mixed with water, oil forms an emulsion of two types: direct oil in water and reverse water in oil. Direct emulsions, composed of oil droplets with a diameter of up to 0.5 microns, are less stable and are typical for oils containing surfactants. When volatile fractions are removed, oil forms viscous inverse emulsions, which can remain on the surface, be carried by the current, wash ashore and settle to the bottom.

Oil slicks cover: vast areas of the Atlantic and Pacific oceans; the South China and Yellow Seas, the Panama Canal zone, a vast area along the coasts are completely covered North America(up to 500-600 km wide), the water area between the Hawaiian Islands and San Francisco in the North Pacific Ocean and many other areas. Such oil films are especially harmful in semi-enclosed, inland and northern seas, where they are brought by current systems. Thus, the Gulf Stream and the North Atlantic Current carry hydrocarbons from the shores of North America and Europe to the areas of the Norwegian and Barents Seas. Especially dangerous is the ingress of oil into the seas of the Arctic Ocean and the Antarctic, since low air temperatures slow down the processes of chemical and biological oxidation of oil even in summer. Thus, oil pollution is global.

It is estimated that even 15 million tons of oil is enough to cover the Atlantic and Arctic oceans with an oil film. But the content of 10 g of oil in 1 m3 of water is detrimental to fish eggs. An oil film (1 ton of oil can pollute 12 km2 of the sea area) reduces the penetration of sunlight, which has a detrimental effect on the photosynthesis of phytoplankton, the main food base for most living organisms of the seas and oceans. One liter of oil is enough to deprive 400,000 liters of sea water of oxygen. pollution world ocean oil

Oil films can: significantly disrupt the exchange of energy, heat, moisture, gases between the ocean and the atmosphere. But the ocean plays a big role in shaping the climate, produces 60-70 oxygen, which is necessary for the existence of life on Earth.

When oil evaporates from the surface of the water, the presence of its vapor in the air adversely affects human health. Particularly distinguished are the water areas: the Mediterranean, Northern, Irish, Java Seas; Mexican, Biscay, Tokyo bays.

Thus, almost the entire area of the coast of Italy, washed by the waters of the Adriatic, Ionian, Pyrrhenian, Ligurian seas, with a total length of about 7,500 km, is polluted with waste from oil refineries and waste from 10 thousand industrial enterprises.

The North Sea is no less polluted with waste. But this is a shelf sea - its average depth is 80 m, and in the Dogger Bank area - until recently, a rich fishing area - 20 m. At the same time, the rivers flowing into it, especially the largest ones, such as: The Thames does not supply the North Sea with clean fresh water, but, on the contrary, they carry thousands of tons of toxic substances into the North Sea every hour.

The danger of the "oil plague" is nowhere so great as in the area between the Elbe and the Thames. This section, where about half a billion tons of crude oil and oil products are transported annually, accounts for 50% of all collisions of ships with a displacement of more than 500 register tons. The sea is also threatened by thousands of kilometers of pipelines carrying oil. There are also accidents on drilling platforms.

If oil covers the gently sloping marshy shores of the southeastern North Sea, the consequences will be much worse. This segment of the coast from the Danish Esbjerg to the Dutch Helder is a unique region of the World Ocean. On the mudflats and in the narrow channels between them, many small marine animals live. Here millions of seabirds nest and find their food, spawn different kinds fish, here, before going out to the open sea, their juveniles are fattened. Oil will destroy everything.

The public rightly pays great attention to tanker disasters, but we must not forget that nature itself pollutes the seas with oil. According to a common theory, oil, one might say, originated in the sea. So, it is believed that it arose from the remains of myriads of the smallest marine organisms, after the death of settling to the bottom and buried by later geological deposits. Now the child threatens the life of the mother. The use of oil by man, its extraction at sea and its transportation by sea are all often considered as deadly danger for the oceans.

In 1978, there were about 4 thousand tankers in the world, and they transported approximately 1,700 million tons of oil by sea (about 60% of world oil consumption). Now approximately 450 million tons of crude oil (15% of world production per year) comes from deposits located under the seabed. Now more than 2 billion tons of oil is extracted from the sea and transported through it. According to the US National Academy of Sciences, of this amount, 1.6 million tons, or one thousand three hundredth, end up in the sea. But these 1.6 million tons make up only 26% of the oil that, in total, enters the sea in a year. The rest of the oil, about three-quarters of the total pollution, comes from bulk carriers (bilge water, residues of fuel and lubricants accidentally or intentionally dumped into the sea), from natural sources, and most of all from cities, especially from enterprises located on coast or on rivers flowing into the sea.

The fate of oil that has entered the sea cannot be described in detail. Firstly, mineral oils that enter the sea have different composition and different properties; secondly, in the sea they are affected by different factors: wind of various strengths and directions, waves, air and water temperature. It is also important how much oil got into the water. The complex interactions of these factors have not yet been fully explored.

When a tanker crashes near the shore, seabirds die: oil glues their feathers. Coastal flora and fauna suffer, beaches and rocks are covered with a hard-to-remove layer of viscous oil. If oil is thrown into the open sea, the consequences are completely different. Significant masses of oil may disappear before reaching the shore.

The relatively rapid absorption of oil by the sea is due to several reasons.

The oil evaporates. Gasoline completely evaporates from the surface of the water in six hours. At least 10% of crude oil evaporates per day, and in about 20 days - 50%. But heavier oil products hardly evaporate.

Oil is emulsified and dispersed, that is, broken into small droplets. Strong sea waves promote the formation of oil-in-water and water-in-oil emulsions. In this case, a continuous carpet of oil breaks, turns into small droplets floating in the water column.

Oil dissolves. It contains substances that are soluble in water, although their share is generally small.

The oil that has disappeared from the surface of the sea due to these phenomena is subjected to slow processes leading to its decomposition - biological, chemical and mechanical.

Biodegradation plays an important role. More than a hundred species of bacteria, fungi, algae and sponges are known to be capable of converting oil hydrocarbons into carbon dioxide and water. Under favorable conditions, due to the activity of these organisms on square meter per day at a temperature of 20--30 ° decomposes from 0.02 to 2 g of oil. Light fractions of hydrocarbons decompose in a few months, but lumps of bitumen disappear only after a few years.

There is a photochemical reaction. Under the action of sunlight, oil hydrocarbons are oxidized by atmospheric oxygen, forming harmless, water-soluble substances.

Heavy oil residues can sink. So, the same lumps of bitumen can be so densely populated by small sessile marine organisms that after a while they sink to the bottom.

Mechanical decomposition also plays a role. Over time, bitumen lumps become brittle and break into pieces.

Birds are most affected by oil, especially when coastal waters are polluted. The oil glues the plumage, it loses its heat-insulating properties, and, moreover, a bird stained with oil cannot swim. Birds freeze and drown. Even cleaning feathers with solvents does not save all the victims. The rest of the inhabitants of the sea suffer less. Numerous studies have shown that oil that has entered the sea does not pose any permanent or long-term danger to organisms living in the water and does not accumulate in them, so that its entry into a person the food chain excluded.

According to the latest data, significant damage to flora and fauna can be inflicted only in special cases. For example, much more dangerous than crude oil are petroleum products made from it - gasoline, diesel fuel, and so on. Dangerous high concentrations of oil in the littoral (tidal zone), especially on the sandy coast.

In these cases, the concentration of oil remains high for a long time, and it does a lot of harm. But fortunately, such cases are relatively rare. Usually, during tanker accidents, oil quickly disperses in water, dilutes, and begins to decompose. It has been shown that oil hydrocarbons can pass through their digestive tract and even through tissues without harm to marine organisms: such experiments were carried out with crabs, bivalves, various types of small fish, and no harmful effects were found for experimental animals.

Oil pollution is a formidable factor affecting the life of the entire oceans. Pollution of high-latitude waters is especially dangerous, where, due to low temperatures, oil products practically do not decompose and are, as it were, “preserved” by ice, so oil pollution can cause serious damage to the environment of the Arctic and Antarctic.

Oil products that have spread over large areas of water basins can change the moisture, gas and energy exchange between the ocean and the atmosphere. Moreover, in the seas of tropical and middle latitudes, the influence of oil pollution should be expected on a smaller scale than in the polar regions, since thermal and biological factors in low latitudes contribute to a more intensive process of self-purification. These factors are also decisive in the kinetics of the decomposition of chemicals. Regional features of the wind regime also cause a change in the quantitative and qualitative composition of oil films, since the wind contributes to the weathering and evaporation of light fractions of oil products. In addition, the wind acts as a mechanical factor in the destruction of film pollution. On the other hand, the effect of oil pollution on the physical and chemical characteristics of the underlying surface in different geographical areas will also not be unambiguous. For example, in the Arctic, oil pollution changes the reflective radiation properties of snow and ice. A decrease in the albedo value and a deviation from the norm in the processes of melting glaciers and drifting ice is fraught with climatic consequences.

Summing up the above, we can draw conclusions about how the pollution of the World Ocean mainly occurs:

1. During offshore drilling, collection of oil in local reservoirs and pumping through main oil pipelines.

2. As offshore oil production grows, the number of its transportation by tankers increases sharply, and, consequently, the number of accidents also increases. In recent years, the number of large tankers carrying oil has increased. The share of supertankers accounts for more than half of the total volume of oil transported. Such a giant, even after turning on emergency braking, travels more than 1 mile (1852 m) to a complete stop. Naturally, the risk of catastrophic collisions for such tankers increases several times. In the North Sea, where the density of tanker traffic is the highest in the world, about 500 million tons of oil are transported annually, 50 (of all collisions) occur.

3. The removal of oil and oil products to the sea with the waters of rivers.

4. The influx of oil products with precipitation - light oil fractions evaporate from the sea surface and enter the atmosphere, thus about 10 (oil and oil products of the total amount) enter the World Ocean.

5. Drainage of untreated water from factories and oil depots located on the sea coasts and in ports.

Literature

1 E.A. Sabchenko, I.G. Orlova, V.A. Mikhailova, R.I. Lisovsky - Oil pollution of the Atlantic Ocean // Priroda.-1983.-No5.-p.111.

2 V.V. Izmailov - The impact of petroleum products on the snow and ice cover of the Arctic // Proceedings of the All-Union Geographical Society. -1980 (March-April).

3 D.P. Nikitin, Yu.V. Novikov, Environment and Man - Moscow: Higher School.-1986.-416p.

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Major ocean pollutants in the world

The main problem is the chemicals that are thrown away by various enterprises. The main contaminants are:

Oil.
Petrol.
Pesticides, fertilizers and nitrates.
Mercury and other harmful chemicals .

Oil is the biggest scourge for the ocean.

As we saw, the first on the list is oil, and this is no coincidence. Oil and petroleum products are the most common pollutants in the oceans. Already at the start 80syears thrown into the ocean every year 15.5 million tons of oil, and this 0.22% of global production. Oil and oil products, gasoline as well as pesticides, fertilizers and nitrates, even mercury and other harmful chemical compounds - all of them during emissions from enterprises enter the oceans. All of the above leads the ocean to the fact that pollution forms its fields to the maximum intensively, and especially in areas of oil production.

Pollution of the World Ocean - what it can lead to

The most important thing to understand is that hocean pollution is an action that is directly related to a person. Accumulated perennial chemicals and toxins are already affecting the development of pollutants in the ocean, and they in turn have a negative impact on marine organisms and the human body. The consequences to which the actions and inaction of people lead are horrendous. Destruction of many species of fish as well as other inhabitants of the ocean waters- this is not all that we get because of the indifferent attitude of man to the Ocean. We should think that the loss can be much, much more than we might think. Do not forget that the oceans have a very important role, he has planetary functions, the ocean is powerful thermal regulator and moisture circulation Earth and the circulation of its atmosphere. Pollution can lead to an irreparable change in all these characteristics. The worst thing that such changes are already observed today. A person can do a lot, he can both save nature and destroy it. We should think about how humanity has already harmed nature, we must understand that much is already irreparable. Every day we become colder and more callous to our home, to our Earth. But we and our descendants still live on it. Therefore we must cherish World Ocean!

Skorodumova O.A.

Introduction.

Our planet could well be called Oceania, since the area occupied by water is 2.5 times the land area. Oceanic waters cover almost 3/4 of the surface of the globe with a layer about 4000 m thick, making up 97% of the hydrosphere, while land waters contain only 1%, and only 2% are bound in glaciers. The oceans, being the totality of all the seas and oceans of the Earth, have a huge impact on the life of the planet. A huge mass of ocean water forms the climate of the planet, serves as a source of precipitation. More than half of the oxygen comes from it, and it also regulates the content of carbon dioxide in the atmosphere, as it is able to absorb its excess. At the bottom of the World Ocean there is an accumulation and transformation of a huge mass of mineral and organic substances, therefore the geological and geochemical processes occurring in the oceans and seas have a very strong influence on the entire earth's crust. It was the Ocean that became the cradle of life on Earth; now it is home to about four-fifths of all living beings on the planet.

Judging by the photographs taken from space, the name “Ocean” would be more suitable for our planet. It has already been said above that 70.8% of the entire surface of the Earth is covered with water. As you know, there are 3 main oceans on Earth - the Pacific, Atlantic and Indian, but the Antarctic and Arctic waters are also considered oceans. Moreover, the Pacific Ocean is larger than all the continents combined. These 5 oceans are not isolated water basins, but a single oceanic massif with conditional boundaries. Russian geographer and oceanographer Yuri Mikhailovich Shakalsky called the entire continuous shell of the Earth - the World Ocean. This is the modern definition. But, besides the fact that once all the continents rose from the water, in that geographical era, when all the continents had already basically formed and had outlines close to modern ones, the World Ocean took possession of almost the entire surface of the Earth. It was a global flood. Evidence of its authenticity is not only geological and biblical. Written sources have come down to us - Sumerian tablets, transcripts of the records of the priests of Ancient Egypt. The entire surface of the Earth, with the exception of some mountain peaks, was covered with water. In the European part of our mainland, the water cover reached two meters, and in the territory of modern China - about 70 - 80 cm.

resources of the oceans.

In our time, the “epoch of global problems”, the World Ocean plays an increasingly important role in the life of mankind. Being a huge pantry of mineral, energy, plant and animal wealth, which - with their rational consumption and artificial reproduction - can be considered practically inexhaustible, the Ocean is able to solve one of the most pressing problems: the need to provide a rapidly growing population with food and raw materials for a developing industry, danger of an energy crisis, lack of fresh water.

The main resource of the World Ocean is sea water. It contains 75 chemical elements, among which are such important ones as uranium, potassium, bromine, magnesium. And although the main product of sea water is still table salt - 33% of world production, magnesium and bromine are already being mined, methods for obtaining a number of metals have long been patented, among them copper and silver, which are necessary for industry, the reserves of which are steadily depleted, when, as in oceanic their waters contain up to half a billion tons. In connection with the development of nuclear energy, there are good prospects for the extraction of uranium and deuterium from the waters of the World Ocean, especially since the reserves of uranium ores on earth are decreasing, and in the Ocean there are 10 billion tons of it, deuterium is practically inexhaustible - for every 5000 atoms of ordinary hydrogen there is one heavy atom. In addition to the isolation of chemical elements, sea water can be used to obtain fresh water necessary for humans. Many commercial desalination methods are now available: chemical reactions are used to remove impurities from water; salt water is passed through special filters; finally, the usual boiling is performed. But desalination is not the only way to obtain potable water. There are bottom sources that are increasingly being found on the continental shelf, that is, in areas of the continental shelf adjacent to the shores of land and having the same geological structure as it. One of these sources, located off the coast of France - in Normandy, gives such an amount of water that it is called an underground river.

The mineral resources of the World Ocean are represented not only by sea water, but also by what is “under water”. The bowels of the ocean, its bottom are rich in mineral deposits. On the continental shelf there are coastal placer deposits - gold, platinum; there are also precious stones - rubies, diamonds, sapphires, emeralds. For example, near Namibia, diamond gravel has been mined underwater since 1962. On the shelf and partly on the continental slope of the Ocean, there are large deposits of phosphorites that can be used as fertilizers, and the reserves will last for the next few hundred years. the very same interesting view The mineral resources of the World Ocean are the famous ferromanganese nodules, which cover vast underwater plains. Concretions are a kind of "cocktail" of metals: they include copper, cobalt, nickel, titanium, vanadium, but, of course, most of all iron and manganese. Their locations are well known, but the results of industrial development are still very modest. But the exploration and production of oceanic oil and gas on the coastal shelf is in full swing, the share of offshore production is approaching 1/3 of the world production of these energy carriers. On an especially large scale, deposits are being developed in the Persian, Venezuelan, Gulf of Mexico, and in the North Sea; oil platforms stretched off the coast of California, Indonesia, in the Mediterranean and Caspian Seas. The Gulf of Mexico is also famous for the sulfur deposit discovered during oil exploration, which is melted from the bottom with the help of superheated water. Another, as yet untouched pantry of the ocean are deep crevices, where a new bottom is formed. So, for example, hot (more than 60 degrees) and heavy brines of the Red Sea depression contain huge reserves of silver, tin, copper, iron and other metals. The extraction of materials in shallow water is becoming more and more important. Around Japan, for example, underwater iron-bearing sands are sucked out through pipes, the country extracts about 20% of coal from sea mines - an artificial island is built over rock deposits and a shaft is drilled that reveals coal seams.

Many natural processes occurring in the World Ocean - movement, temperature regime of waters - are inexhaustible energy resources. For example, the total power of the tidal energy of the Ocean is estimated at 1 to 6 billion kWh. This property of ebbs and flows was used in France in the Middle Ages: in the 12th century, mills were built, the wheels of which were driven by a tidal wave. Today in France there are modern power plants that use the same principle of operation: the rotation of the turbines at high tide occurs in one direction, and at low tide - in the other. The main wealth of the World Ocean is its biological resources (fish, zool.- and phytoplankton and others). The biomass of the Ocean has 150 thousand species of animals and 10 thousand algae, and its total volume is estimated at 35 billion tons, which may well be enough to feed 30 billion! Human. Catching annually 85-90 million tons of fish, it accounts for 85% of the used marine products, shellfish, algae, humanity provides about 20% of its needs for proteins of animal origin. The living world of the Ocean is a huge food resource that can be inexhaustible if used properly and carefully. The maximum fish catch should not exceed 150-180 million tons per year: it is very dangerous to exceed this limit, as irreparable losses will occur. Many varieties of fish, whales, and pinnipeds have almost disappeared from ocean waters due to immoderate hunting, and it is not known whether their population will ever recover. But the population of the Earth is growing at a rapid pace, increasingly in need of marine products. There are several ways to increase its productivity. The first is to remove from the ocean not only fish, but also zooplankton, part of which - Antarctic krill - has already been eaten. It is possible, without any damage to the Ocean, to catch it in much larger quantities than all the fish caught at the present time. The second way is to use the biological resources of the open ocean. biological productivity The ocean is especially large in the region of the rise of deep waters. One of these upwellings, located off the coast of Peru, provides 15% of the world's fish production, although its area is no more than two hundredths of a percent of the entire surface of the World Ocean. Finally, the third way is the cultural breeding of living organisms, mainly in coastal zones. All these three methods have been successfully tested in many countries of the world, but locally, therefore, the fish catch, which is detrimental in terms of volume, continues. At the end of the 20th century, the Norwegian, Bering, Okhotsk, and Sea of Japan were considered the most productive water areas.

The ocean, being a pantry of the most diverse resources, is also a free and convenient road that connects distant continents and islands. Maritime transport provides almost 80% of transportation between countries, serving the growing global production and exchange. The oceans can serve as a waste recycler. Thanks to the chemical and physical effects of its waters and the biological influence of living organisms, it disperses and purifies the main part of the waste entering it, maintaining the relative balance of the Earth's ecosystems. For 3000 years, as a result of the water cycle in nature, all the water in the oceans is renewed.

Pollution of the oceans.

Oil and oil products

a). Paraffins (alkenes). (up to 90% of the total composition) - stable substances, the molecules of which are expressed by a straight and branched chain of carbon atoms. Light paraffins have maximum volatility and solubility in water.

b). Cycloparaffins. (30 - 60% of the total composition) saturated cyclic compounds with 5-6 carbon atoms in the ring. In addition to cyclopentane and cyclohexane, bicyclic and polycyclic compounds of this group are found in oil. These compounds are very stable and difficult to biodegrade.

c). Aromatic hydrocarbons. (20 - 40% of the total composition) - unsaturated cyclic compounds of the benzene series, containing 6 carbon atoms in the ring less than cycloparaffins. Oil contains volatile compounds with a molecule in the form of a single ring (benzene, toluene, xylene), then bicyclic (naphthalene), polycyclic (pyrone).

G). Olefins (alkenes). (up to 10% of the total composition) - unsaturated non-cyclic compounds with one or two hydrogen atoms at each carbon atom in a molecule that has a straight or branched chain.

Oil and oil products are the most common pollutants in the oceans. By the beginning of the 1980s, about 16 million tons of oil were annually entering the ocean, which accounted for 0.23% of world production. The greatest losses of oil are associated with its transportation from production areas. Emergencies, discharge of washing and ballast water overboard by tankers - all this leads to the presence of permanent pollution fields along sea routes. In the period 1962-79, about 2 million tons of oil entered the marine environment as a result of accidents. Over the past 30 years, since 1964, about 2,000 wells have been drilled in the World Ocean, of which 1,000 and 350 industrial wells have been equipped in the North Sea alone. Due to minor leaks, 0.1 million tons of oil are lost annually. Large masses of oil enter the seas along rivers, with domestic and storm drains. The volume of pollution from this source is 2.0 million tons / year. Every year, 0.5 million tons of oil enters with industrial effluents. Getting into the marine environment, oil first spreads in the form of a film, forming layers of various thicknesses.

The oil film changes the composition of the spectrum and the intensity of light penetration into the water. The light transmission of thin films of crude oil is 11-10% (280nm), 60-70% (400nm). A film with a thickness of 30-40 microns completely absorbs infrared radiation. When mixed with water, oil forms an emulsion of two types: direct oil in water and reverse water in oil. Direct emulsions, composed of oil droplets with a diameter of up to 0.5 μm, are less stable and are typical for oils containing surfactants. When volatile fractions are removed, oil forms viscous inverse emulsions, which can remain on the surface, be carried by the current, wash ashore and settle to the bottom.

Pesticides

Pesticides are a group of man-made substances used to control pests and plant diseases. Pesticides are divided into the following groups:

Insecticides to control harmful insects,

Fungicides and bactericides - to combat bacterial plant diseases,

Herbicides against weeds.

It has been established that pesticides, destroying pests, harm many beneficial organisms and undermine the health of biocenoses. In agriculture, there has long been a problem of transition from chemical (polluting) to biological (environmentally friendly) methods of pest control. Currently, more than 5 million tons of pesticides enter the world market. About 1.5 million tons of these substances have already entered the terrestrial and marine ecosystems by ash and water. The industrial production of pesticides is accompanied by the appearance of a large number of by-products that pollute wastewater. In the aquatic environment, representatives of insecticides, fungicides and herbicides are more common than others. Synthesized insecticides are divided into three main groups: organochlorine, organophosphorus and carbonates.

Organochlorine insecticides are obtained by chlorination of aromatic and heterocyclic liquid hydrocarbons. These include DDT and its derivatives, in the molecules of which the stability of aliphatic and aromatic groups in the joint presence increases, various chlorinated derivatives of chlorodiene (eldrin). These substances have a half-life of up to several decades and are very resistant to biodegradation. In the aquatic environment, polychlorinated biphenyls are often found - derivatives of DDT without an aliphatic part, numbering 210 homologues and isomers. Over the past 40 years, more than 1.2 million tons of polychlorinated biphenyls have been used in the production of plastics, dyes, transformers, and capacitors. Polychlorinated biphenyls (PCBs) enter the environment as a result of industrial wastewater discharges and the incineration of solid waste in landfills. The latter source delivers PBCs to the atmosphere, from where they fall out with atmospheric precipitation in all regions of the globe. Thus, in snow samples taken in Antarctica, the content of PBC was 0.03 - 1.2 kg. / l.

Synthetic surfactants

Detergents (surfactants) belong to an extensive group of substances that lower the surface tension of water. They are part of synthetic detergents (SMC), widely used in everyday life and industry. Together with wastewater, surfactants enter the mainland waters and the marine environment. SMS contain sodium polyphosphates, in which detergents are dissolved, as well as a number of additional ingredients that are toxic to aquatic organisms: flavoring agents, bleaching agents (persulphates, perborates), soda ash, carboxymethylcellulose, sodium silicates. Depending on the nature and structure of the hydrophilic part of the surfactant molecules, they are divided into anionic, cationic, amphoteric, and nonionic. The latter do not form ions in water. The most common among the surfactants are anionic substances. They account for more than 50% of all surfactants produced in the world. The presence of surfactants in industrial wastewater is associated with their use in such processes as flotation beneficiation of ores, separation of chemical technology products, production of polymers, improvement of conditions for drilling oil and gas wells, and equipment corrosion control. In agriculture, surfactants are used as part of pesticides.

Compounds with carcinogenic properties

Carcinogenic substances are chemically homogeneous compounds that exhibit transforming activity and the ability to cause carcinogenic, teratogenic (violation of embryonic development processes) or mutagenic changes in organisms. Depending on the conditions of exposure, they can lead to growth inhibition, accelerated aging, disruption of individual development, and changes in the gene pool of organisms. Substances with carcinogenic properties include chlorinated aliphatic hydrocarbons, vinyl chloride, and especially polycyclic aromatic hydrocarbons (PAHs). The maximum amount of PAHs in present-day sediments of the World Ocean (more than 100 µg/km of dry matter mass) was found in tectonically active zones subject to deep thermal impact. The main anthropogenic sources of PAHs in the environment are the pyrolysis of organic substances during the combustion of various materials, wood, and fuel.

Heavy metals

Heavy metals (mercury, lead, cadmium, zinc, copper, arsenic) are among the common and highly toxic pollutants. They are widely used in various industrial productions, therefore, despite the treatment measures, the content of heavy metal compounds in industrial wastewater is quite high. Large masses of these compounds enter the ocean through the atmosphere. Mercury, lead and cadmium are the most dangerous for marine biocenoses. Mercury is transported to the ocean with continental runoff and through the atmosphere. During the weathering of sedimentary and igneous rocks, 3.5 thousand tons of mercury are released annually. The composition of atmospheric dust contains about 121 thousand. tons of mercury, and a significant part is of anthropogenic origin. About half of the annual industrial production of this metal (910 thousand tons / year) ends up in the ocean in various ways. In areas polluted by industrial waters, the concentration of mercury in solution and suspension is greatly increased. At the same time, some bacteria convert chlorides into highly toxic methyl mercury. Contamination of seafood has repeatedly led to mercury poisoning of the coastal population. By 1977, there were 2,800 victims of Minomata disease, which was caused by waste products from factories for the production of vinyl chloride and acetaldehyde, which used mercury chloride as a catalyst. Insufficiently treated wastewater from enterprises entered the Minamata Bay. Pigs are a typical trace element found in all components of the environment: in rocks, soils, natural waters, the atmosphere, and living organisms. Finally, pigs are actively dispersed into the environment during human activities. These are emissions from industrial and domestic effluents, from smoke and dust from industrial enterprises, from exhaust gases from internal combustion engines. The migration flow of lead from the continent to the ocean goes not only with river runoff, but also through the atmosphere.

With continental dust, the ocean receives (20-30) * 10 ^ 3 tons of lead per year.

Dumping of waste into the sea for the purpose of disposal

Many countries with access to the sea carry out marine burial of various materials and substances, in particular soil excavated during dredging, drill slag, industrial waste, construction waste, solid waste, explosives and chemicals, and radioactive waste. The volume of burials amounted to about 10% of the total mass of pollutants entering the World Ocean. The basis for dumping in the sea is the ability of the marine environment to process a large amount of organic and inorganic substances without much damage to the water. However, this ability is not unlimited. Therefore, dumping is considered as a forced measure, a temporary tribute to the imperfection of technology by society. Industrial slags contain a variety of organic substances and heavy metal compounds. Household waste contains on average (by weight of dry matter) 32-40% of organic matter; 0.56% nitrogen; 0.44% phosphorus; 0.155% zinc; 0.085% lead; 0.001% mercury; 0.001% cadmium. During the discharge, the passage of the material through the water column, part of the pollutants goes into solution, changing the quality of the water, the other is sorbed by suspended particles and goes into bottom sediments. At the same time, the turbidity of the water increases. The presence of organic substances purely leads to the rapid consumption of oxygen in water and not caustically to its complete disappearance, the dissolution of suspensions, the accumulation of metals in dissolved form, and the appearance of hydrogen sulfide. The presence of a large amount of organic matter creates a stable reducing environment in the soil, in which a special type of interstitial water appears, containing hydrogen sulfide, ammonia, and metal ions. Benthic organisms and others are affected to varying degrees by the discharged materials. In the case of the formation of surface films containing petroleum hydrocarbons and surfactants, gas exchange at the air-water interface is disturbed. Pollutants entering the solution can accumulate in the tissues and organs of hydrobionts and have a toxic effect on them. The dumping of dumping materials to the bottom and prolonged increased turbidity of the given water leads to the death of inactive forms of benthos from suffocation. In surviving fish, mollusks and crustaceans, the growth rate is reduced due to the deterioration of feeding and breathing conditions. The species composition of a given community often changes. When organizing a system for controlling waste emissions into the sea, the determination of dumping areas, the determination of the dynamics of pollution of sea water and bottom sediments is of decisive importance. To identify possible volumes of discharge into the sea, it is necessary to carry out calculations of all pollutants in the composition of the material discharge.

thermal pollution

Thermal pollution of the surface of reservoirs and coastal marine areas occurs as a result of the discharge of heated wastewater from power plants and some industrial production. The discharge of heated water in many cases causes an increase in water temperature in reservoirs by 6-8 degrees Celsius. The area of heated water spots in coastal areas can reach 30 square meters. km. A more stable temperature stratification prevents water exchange between the surface and bottom layers. The solubility of oxygen decreases, and its consumption increases, since with increasing temperature, the activity of aerobic bacteria that decompose organic matter increases. The species diversity of phytoplankton and the entire flora of algae is increasing. Based on the generalization of the material, it can be concluded that the effects of anthropogenic impact on the aquatic environment are manifested at the individual and population-biocenotic levels, and the long-term effect of pollutants leads to a simplification of the ecosystem.

Protection of the seas and oceans

The most serious problem of the seas and oceans in our century is oil pollution, the consequences of which are detrimental to all life on Earth. Therefore, in 1954, an international conference was held in London to work out concerted action to protect the marine environment from oil pollution. It adopted a convention defining the obligations of states in this area. Later, in 1958, four more documents were adopted in Geneva: on the high seas, on the territorial sea and the contiguous zone, on the continental shelf, on fishing and the protection of living resources of the sea. These conventions have legally fixed the principles and norms of maritime law. They obligated each country to develop and enforce laws prohibiting the pollution of the marine environment with oil, radio waste and other harmful substances. A conference held in London in 1973 adopted documents on the prevention of pollution from ships. According to the adopted convention, each ship must have a certificate - evidence that the hull, mechanisms and other equipment are in good condition and do not cause damage to the sea. Compliance with certificates is checked by the inspection when entering the port.

Drainage of oily waters from tankers is prohibited; all discharges from them must be pumped out only to onshore reception points. Electrochemical installations have been created for the treatment and disinfection of ship wastewater, including household wastewater. The Institute of Oceanology of the Russian Academy of Sciences has developed an emulsion method for cleaning sea tankers, which completely excludes the ingress of oil into the water area. It consists in adding several surfactants (ML preparation) to the wash water, which allows cleaning on the ship itself without discharging contaminated water or oil residues, which can be subsequently regenerated for further use. It is possible to wash up to 300 tons of oil from each tanker. In order to prevent oil leaks, the designs of oil tankers are being improved. Many modern tankers have a double bottom. If one of them is damaged, the oil will not spill out, it will be delayed by the second shell.

Ship captains are obliged to record in special logs information about all cargo operations with oil and oil products, to note the place and time of delivery or discharge of contaminated wastewater from the ship. For the systematic cleaning of water areas from accidental spills, floating oil skimmers and side barriers are used. Also, in order to prevent the spread of oil, physical chemical methods. A preparation of a foam group has been created, which, when in contact with an oil slick, completely envelops it. After pressing, the foam can be reused as a sorbent. Such drugs are very convenient due to ease of use and low cost, but their mass production has not yet been established. There are also sorbent agents based on plant, mineral and synthetic substances. Some of them can collect up to 90% of spilled oil. The main requirement for them is unsinkability. After oil is collected by sorbents or mechanical means, a thin film always remains on the surface of the water, which can be removed by spraying chemicals that decompose it. But at the same time, these substances must be biologically safe.

In Japan, a unique technology has been created and tested, with the help of which it is possible to eliminate a giant spot in a short time. Kansai Sagge Corporation has released ASWW reagent, the main component of which is specially treated rice hulls. Sprayed on the surface, the drug absorbs the ejection within half an hour and turns into a thick mass that can be pulled off with a simple net. The original cleaning method was demonstrated by American scientists in the Atlantic Ocean. A ceramic plate is lowered under the oil film to a certain depth. An acoustic record is connected to it. Under the action of vibration, it first accumulates in a thick layer above the place where the plate is installed, and then mixes with water and begins to gush. An electric current applied to the plate sets fire to the fountain, and the oil burns completely.

To remove oil stains from the surface of coastal waters, American scientists have created a modification of polypropylene that attracts fat particles. On a catamaran boat, a kind of curtain made of this material was placed between the hulls, the ends of which hang down into the water. As soon as the boat hits the slick, the oil sticks firmly to the "curtain". All that remains is to pass the polymer through the rollers of a special device that squeezes the oil into a prepared container. Since 1993, the dumping of liquid radioactive waste (LRW) has been banned, but their number is steadily growing. Therefore, in order to protect the environment, in the 1990s, projects for the treatment of LRW began to be developed. In 1996, representatives of Japanese, American and Russian firms signed a contract for the construction of an installation for the processing of liquid radioactive waste accumulated in Far East Russia. The government of Japan allocated 25.2 million dollars for the implementation of the project. However, despite some success in finding effective means to eliminate pollution, it is too early to talk about solving the problem. It is impossible to ensure the cleanliness of the seas and oceans only by introducing new methods of cleaning water areas. The central task that all countries need to solve together is the prevention of pollution.

Conclusion

The consequences, to which the wasteful, careless attitude of mankind towards the Ocean leads, are terrifying. The destruction of plankton, fish and other inhabitants of ocean waters is far from all. The damage could be much greater. Indeed, the World Ocean has general planetary functions: it is a powerful regulator of the moisture circulation and thermal regime of the Earth, as well as the circulation of its atmosphere. Pollution can cause very significant changes in all these characteristics, which are vital for the climate and weather regime on the entire planet. Symptoms of such changes are already observed today. Severe droughts and floods are repeated, destructive hurricanes appear, severe frosts come even to the tropics, where they never happened. Of course, it is not yet possible to even approximately estimate the dependence of such damage on the degree of pollution. Oceans, however, the relationship undoubtedly exists. Be that as it may, the protection of the ocean is one of the global problems of mankind. The Dead Ocean is a dead planet, and therefore all of humanity.

Bibliography

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2. Textbook on geography. Yu.N.Gladky, S.B.Lavrov.

3. "Ecology of the environment and man", Yu.V. Novikov. 1998

4. "Ra" Thor Heyerdahl, "Thought", 1972

5. Stepanovskikh, "Environmental Protection".