The phenomenon of eutrophication occurs due to temperature differences. Measures to combat eutrophication of water bodies. The water space of the planet

anthropogenic eutrophication of water bodies and watercourses, which means an increase in the level of trophy of water bodies associated with human activity, resulting from excessive intake of nutrients (nitrogen, phosphorus) into them and accompanied by a characteristic complex of ecosystem changes.

To assess the degree of eutrophication of water bodies, biological, chemical and physical indicators are used, which are different for surface and deep waters. The main agents of eutrophication can be nitrogen and phosphorus compounds, mainly in the form of nitrates and phosphates. During eutrophication, an aquatic ecosystem successively goes through several stages. First, there is an accumulation of mineral salts of nitrogen and/or phosphorus in the water. This stage, as a rule, is short-lived, since the incoming limiting element is immediately involved in the circulation and the stage of intensive development of algae begins. Phytoplankton biomass increases, water turbidity increases, oxygen concentration in the upper layers of water increases. Then comes the stage of algae death, aerobic degradation of detritus occurs. Bottom silts with a high content of organic matter are intensively deposited. Changes in zoocenosis are noted (replacement salmon fish cyprinids). Finally, there is a complete disappearance of oxygen in the deep layers and anaerobic fermentation begins. The formation of hydrogen sulfide, organosulfur compounds and ammonia is characteristic.

Ecological consequences of the creation of reservoirs

Environmental consequences of the creation of reservoirs Negative: Flooding of large areas of fertile land, flooding of the adjacent territory; Mode change groundwater(salinization, waterlogging, etc.); Coastal processing; Activation of seismic activity. Positive: Increased sustainable river flow; Reducing the destructive effects of floods; Accumulation of water runoff of the reservoir; Reducing the processes of overgrowth of lakes of bays in the mouths of rivers

Hydrosphere protection

Surface waters are protected from clogging (pollution with large debris), pollution and depletion.

To prevent clogging, measures are taken to prevent the entry of construction debris, solid waste, timber rafting residues and other items into surface water bodies and rivers that adversely affect water quality, fish habitats, etc. The most important and most difficult problem is the protection of surface waters from pollution. The goal provides for the following environmental protection measures: the development of waste-free and water-free technologies; introduction of water recycling systems; wastewater treatment (industrial, municipal, etc.); sewage injection into deep aquifers; purification and disinfection of surface water used for water supply and other purposes. Due to the huge variety of composition of wastewater, there are various ways their treatment: mechanical, physico-chemical, chemical, biological, etc. During mechanical treatment, up to 90% of insoluble mechanical impurities are removed from industrial wastewater by filtering, settling and filtering varying degrees dispersion (sand, clay particles, scale, etc.), and from domestic wastewater - up to 60%. The main chemical methods include neutralization and oxidation. In the first case, to neutralize acids and alkalis in wastewater special reagents are introduced (lime, soda ash, ammonia), in the second - various oxidizing agents. With their help, wastewater is freed from toxic and other components. Physical and chemical treatment uses: coagulation - the introduction of coagulants (ammonium salts, iron, copper, sludge waste, etc.) into wastewater to form flocculent sediments, which are then easily removed; sorption - the ability of certain substances (bentonite clay, activated carbon, zeolites, silica gel, peat, etc.) to absorb pollution. By the sorption method, it is possible to extract valuable soluble substances from wastewater and their subsequent disposal; flotation - passing air through wastewater. Gas bubbles capture surfactants, oil, oils and other contaminants as they move up and form an easily removable foam layer on the surface of the water. biological (biochemical) method. The method is based on the ability of microorganisms to use organic and some inorganic compounds contained in wastewater (hydrogen sulfide, ammonia, nitrites, sulfides, etc.) for their development. Cleaning is carried out in natural conditions (irrigation fields, filtration fields, biological ponds, etc.) and in artificial structures (aerotanks, biofilters, circulating oxidizing channels). To combat the depletion of fresh groundwater reserves suitable for drinking water supply, various measures are envisaged, including: regulation of the groundwater withdrawal regime; more rational distribution of water intakes over the area; determination of the value of operational reserves as the limit of their rational use; the introduction of a crane mode of operation of self-flowing artesian wells. Measures to combat groundwater pollution: are divided into: 1) preventive and 2) special, the task of which is to localize or eliminate the source of pollution.

Aral disaster. Options for solving the Aral problem.

The degradation of the Aral Sea was the result of "planned" technogenic agrarian development for 30 years. And it is not necessary to speak here of an accident, the suddenness of the death of the Aral Sea. The Aral crisis can be called a systematic catastrophe caused by incompetent and environmentally destructive planning for the development of the economy of the Aral region, a vivid manifestation of which was the "cotton monopoly", underestimation and ignoring of long-term negative environmental consequences. For the needs of irrigated agriculture, the vast majority of the water consumed in the region is taken. In conditions of arid climate, water shortage, imperfection of irrigation infrastructure, this leads to almost complete withdrawal of water resources. In recent years, only 4-8 km3 of water has entered the sea, while only 33-35 km3 is required to maintain its level. The number of negative environmental consequences of the Aral Sea crisis include an annual decrease in sea level by 80-100 cm, a decrease in volume by almost 4 times, and an increase in the salt content in water by 2.5 times. The Aral is fed by two rivers - the Syr Darya and the Amu Darya, and in individual years the latter does not reach the sea at all. Extremely dangerous consequences include the huge removal of sand and salt from the exposed bottom of the former sea. Every year about 75 million tons of sand and salt are lifted by the winds and carried hundreds of kilometers around. The diversity of wildlife species has catastrophically decreased. If earlier 178 species of animals lived in the sea region, now this number has decreased to 38! The water in the Aral Sea is extremely polluted with residues of pesticides and mineral fertilizers. This is a consequence of excessive chemicalization of agriculture in the region. The ecological crisis of the Aral Sea region has changed and economic structures region, destroyed many traditional activities. Fish processing plants also closed. The same sad fate befell maritime transport. Dozens of ships stand in the middle of the desert like monuments of the ecological catastrophe of the Aral Sea, dozens of ships stand in the middle of the desert. The ecological and economic crisis of the Aral Sea region has also given rise to such a negative social phenomenon as mass unemployment. Here the most famous project is the transfer of part of the flow Siberian rivers to Central Asia. The following figures speak of the grandeur and cyclopean nature of this project: the length of the canal from Siberia was to be about 2400 km, the width - up to 200 m, the cost in prices of the 80s. - 90 billion rubles. Compared to this channel, the Great Wall of China and Pyramids of Egypt- Kids toys. The transfer project was practically unjustified neither ecologically, nor economically, nor technically.

More realistic seems to be a twin variant that appeared not so long ago: a project to build a canal from the Caspian Sea. It has the same disadvantages as the Siberian version. To implement the project, it is necessary to dig a channel in the desert with a length of 500 km. In addition, due to the inclination of the earth's surface from the Aral Sea to the Caspian Sea, in order for water to flow, it must first be raised to a height of 80 m. This will require enormous energy costs.

Eutrophication is the process of deterioration of water quality due to excessive intake of the so-called "biogenic elements" into the reservoir, primarily nitrogen and phosphorus compounds. Eutrophication, a normal natural process associated with the constant flushing of biogenic elements into water bodies from the catchment area, may be the result of natural aging of a water body. However, in Lately in areas with a high population density or with intensive agriculture, the intensity of this process has increased many times due to the discharge of municipal wastewater, wastewater from livestock farms and food industry enterprises into water bodies, as well as due to the flushing of excessively applied fertilizers from the fields. The mechanism of the impact of eutrophication on the ecosystems of water bodies is as follows.

1. An increase in the content of biogenic elements in the upper water horizons causes the rapid development of plants in this zone (primarily phytoplankton, as well as fouling algae) and an increase in the number of zooplankton feeding on phytoplankton. As a result, water transparency rarely decreases, penetration depth sun rays decreases, and this leads to the death of bottom plants from lack of light. After the death of bottom aquatic plants, it is the turn of the death of other organisms for which these plants create habitats or for which they are an upstream link in the food chain.

2. Plants that multiply strongly in the upper water horizons (especially algae) have a much larger total body surface and biomass. At night, photosynthesis in these plants does not occur, while the process of respiration continues. As a result, in the early hours warm days oxygen in the upper water horizons is practically exhausted, and the death of organisms living in these horizons and demanding oxygen content is observed (the so-called “summer freeze” occurs).

3. Dead organisms sooner or later sink to the bottom of the reservoir, where they decompose. However, as we noted in paragraph 1, benthic vegetation dies due to eutrophication, and oxygen production is practically absent here. If we take into account that the total production of the reservoir increases during eutrophication (see paragraph 2), there is an imbalance between the production and consumption of oxygen in the near-bottom horizons, oxygen is rapidly consumed here, and all this leads to the death of oxygen-demanding benthic and benthic fauna. A similar phenomenon observed in the second half of winter in closed shallow water bodies is called "winter freeze".

4. In the bottom soil, deprived of oxygen, anaerobic decay of dead organisms occurs with the formation of such strong poisons, like phenols and hydrogen sulfide, and such a powerful "greenhouse gas" (in its effect in this regard, surpassing carbon dioxide by 120 times), like methane. As a result, the process of eutrophication destroys most species of flora and fauna of the reservoir, almost completely destroying or very strongly transforming its ecosystems, and greatly worsens the sanitary and hygienic qualities of its water, up to its complete unsuitability for swimming and drinking water supply.

5. The main anthropogenic sources of phosphorus and nitrogen: untreated wastewater (especially from livestock complexes) and washout of fertilizers from fields. Many countries have banned the use of sodium orthophosphate in laundry detergents to reduce eutrophication of water bodies.

· Signs such as dead fish can indicate contamination, but there are more sophisticated methods to detect it.

Fresh water pollution is measured in terms of biochemical oxygen demand (BOD)- i.e. how much oxygen the pollutant absorbs from the water. This indicator allows you to assess the degree of oxygen starvation of aquatic organisms. While the BOD norm for European rivers is 5 mg/l, in untreated domestic wastewater this figure reaches 350 mg/l.

· The situation that has developed in the last 20 years is alarming, as a significant part of the reservoirs has become covered with greenery and has become toxic due to their pollution. Fresh water is turning into a breeding ground for potentially dangerous species of bacteria, protozoa and fungi. Bacteria such as salmonella and listeria, as well as protozoa such as cryptosporidium, are no less dangerous to human health than cholera was in Europe in the 19th century.

Algae on the surface of the water acts like a thick forest canopy, blocking sunlight. This has a detrimental effect on oxygen-producing algae, on which the life of aquatic invertebrates and vertebrates depends. In addition, certain types of blue-green algae emit toxic substances that affect fish and other aquatic organisms. As a result, many water activities are banned during the summer months due to algae growth and toxicity. The reason for the flowering of the latter in lakes and reservoirs can also be deforestation and fertilization of forest soil - in both cases, nutrients enter the water.

· Acid rain has caused a number of major environmental disasters in Canada, the United States and Northwestern Europe. The water in 16,000 of the 85,000 lakes in Sweden has oxidized, and in 5,000 of them the fish have completely disappeared. Since 1976, lime has been added to the waters of 4,000 lakes to neutralize the acid and restore the chemical balance. The same measures are resorted to by Scotland and Norway, where, for a similar reason, fish stocks have decreased by 40%. In the eastern United States, the loss of trout caused by the acidification of sport fishing waters is estimated to cost $1 billion annually. However, coastal communities pay for the liming of lakes. So, an excess of calcium led to the death of 90% of the peat moss growing nearby, cuckoo flax and reindeer moss. A significant part of acid rain comes to Scandinavia from the west, where the British industry produces about 3.7 million tons of sulfur dioxide per year.

· As a rule, pollution of water bodies leads to the death of wildlife, primarily fish. But rapid re-colonization and restoration of populations is possible, especially with the help of humans. Some invertebrates migrate to affected areas from upstream areas; others fly here in a matter of hours. Some organisms (such as river limpets, whose gills become clogged with silt) are sensitive to ecological imbalance, while other species (including mayflies) are unaffected by rather high levels of pollution. Tubeworms feed on bacteria and larvae of various bell species, while leeches (among them Helobdella stagnalis) easily tolerate eutrophication and low oxygen levels.

Question 6 river protection

Water protection zone is a territory adjacent to the water areas of rivers, lakes, reservoirs and other surface water bodies, where a special regime of economic or other types of activity is established. Within its limits, a coastal protective strip with a stricter protective regime is distinguished, on which additional restrictions on nature use are introduced. The establishment of water protection zones is aimed at ensuring the prevention of pollution, clogging, silting and depletion of water bodies, as well as the preservation of the habitat of animals and animals. flora reservoirs.

The minimum width of water protection zones for lakes and reservoirs is accepted with a water area of up to 2 sq. km - 300 m, from 2 sq. km and more - 500 m.

Regulations within water protection zones prohibit:

· - Carrying out aviation - chemical works;

- application chemicals control of pests, plant diseases and weeds;

· - use of manure for soil fertilization;

· - placement of warehouses of pesticides, mineral fertilizers and fuels and lubricants; sites for refueling equipment with pesticides, livestock breeding complexes and farms, storage and burial sites for industrial, domestic and agricultural waste, cemeteries and animal burial grounds, sewage storage facilities;

- storage of manure and garbage;

· - refueling, washing and repair of cars and other machines and mechanisms;

· - placement of summer cottages and garden plots with a width of the water protection zone of less than 100 m and a steepness of the slopes of the adjacent territories of more than 3 degrees;

- location of parking lots Vehicle, including in the territories of summer cottages and garden plots;

· - carrying out fellings of the main use;

The minimum width of coastal protective strips is set depending on the types of land and the steepness of the slopes of the territories adjacent to water body, and ranges from 15 to 100 m.

Within coastal protective belts In addition to these restrictions, the following are prohibited:

Plowing land;

Application of fertilizers;

Storage of dumps of eroded soils;

Grazing and organization of summer camps for livestock (except for the use of traditional watering places),

Installation of seasonal stationary tent camps, placement of summer cottages and garden plots and allocation of plots for individual construction;

Movement of cars and tractors, except for special-purpose vehicles

NEUTRALIZATION AND CLEANING OF WASTE WATER. RATIONAL USE OF WATER RESOURCES

In rivers and other bodies of water, a natural process of self-purification of water occurs. However, it runs slowly. While industrial and domestic discharges were small, the rivers themselves coped with them. In our industrial age, due to the sharp increase in waste, it has become necessary to neutralize, purify and dispose of wastewater.

The release of wastewater from pollution is a difficult production.

In it, as in any other production, there are raw materials - wastewater and finished products- purified water.

Wastewater treatment methods can be divided into mechanical, physico-chemical and biological. When they are used together, the method of purification and disposal of wastewater is called combined. The use of one method or another in each case is determined by the nature of the contamination and the degree of harmfulness of the impurities. ;

The essence of the mechanical method is that mechanical impurities are removed from wastewater by settling and filtration. Coarsely dispersed particles, depending on their size, are captured by gratings and sieves of various designs, and surface contaminants - by oil traps, oil and resin traps, etc. Mechanical treatment allows you to separate up to 1/3 of insoluble impurities from domestic wastewater, and more than 9/10 from industrial wastewater.

With the physico-chemical method of treatment, finely dispersed and dissolved inorganic impurities are removed from wastewater and organic non-oxidizable and poorly oxidizable substances are destroyed.

Finds wide application electrolysis. It consists in the destruction of organic substances in wastewater and the extraction of metals, acids and other inorganic substances. Electrolytic wastewater treatment is carried out in special facilities - electrolyzers. It is effective in lead and copper plants, paint and varnish and some other industries. Chemical cleaning achieves a reduction in the content of insoluble impurities up to 95%, soluble - up to 25%.

Physicochemical methods include flotation, extraction, adsorption, ion exchange, oxidation, evaporation, etc.

Flotation makes it possible to accelerate the clarification of industrial wastewater and remove from them both suspended solids and oil, oil products, fats and surface-active substances (surfactants). The essence of this process is to saturate the effluent with air, to the bubbles of which particles of solid substances stick, together with them floating to the surface.

Extraction wastewater is released from organic substances that are concentrated in solvents (carbon tetrachloride, chloroform, dibutyl ether, butylisobutyl acetate, benzene, chlorobenzene, nitrobenzene, etc.).

Adsorption used for low content of organic matter in wastewater. As an adsorbent, activated carbon and organic, synthetic sorbents are used.

Ion exchange methods industrial wastewater treatment makes it possible to extract and return valuable substances: zinc, nickel, phenols, detergents, radioactive compounds, etc. Synthetic ion-exchange resins are used for these purposes. In the ion-exchange method, light hydrogen ions or alkali metal ions are replaced by non-ferrous and heavy metals. It is valuable in that the substance removed is concentrated rather than destroyed.

Oxidation - one of the promising methods of wastewater treatment. Ozone, chlorine, chlorine dioxide, potassium permanganate and other oxidizing agents are used to oxidize residual organic substances dissolved in water that are resistant to biological destruction.

At evaporation waste water is heated to a boil. Saturated water vapor extracts impurities from wastewater. Then the steam is passed through a heated absorber, in which impurities are retained.

If necessary, additional treatment of wastewater that has undergone mechanical and biological treatment is used. Therefore, it is considered the third stage of purification. The most common methods for post-treatment of wastewater include filtration through sand filters and long-term storage of wastewater in storage ponds.

Thickets of reeds should be protected from extermination, since, along with bacteria and algae, they act as living filters that absorb many pollutants and destroy pathogenic bacteria with their secretions. Dense thickets of reeds on an area of 1 ha absorb from water and soil and accumulate in their tissues up to 5-6 tons of various salts, healing rivers and reservoirs.

The soil of irrigation systems cleans wastewater well; reuse of treated wastewater reduces the need for clean water by reducing the amount of wastewater discharged into the sewer. The total area of irrigation systems in the country that use wastewater is 230,000 ha. This makes it possible to prevent pollution of 10 km 3 of water per head.

In semi-desert conditions, wastewater is disposed of in filtration fields, which in waterless areas, where irrigation water is especially valued, cannot be considered rational, since according to a number of irrigation indicators, wastewater is suitable for irrigating tree plantations of various categories. Besides. the concentration of wastewater in large volumes significantly worsens the condition of the territory adjacent to the filtration fields. Therefore, it is advisable to grow tree plantations instead of creating filtration fields. In this case, as a result of transpiration, an ideal purification of industrial wastewater, humidification of the air basin and, in general, an improvement in the microclimate and sanitary condition of cities occur.

Contaminated wastewater is also cleaned using ultrasound. ozone and high pressure. Cleaning by chlorination has proven itself well.

An important role should be played by the biological method of wastewater treatment, based on the use of the laws of biochemical and physiological self-purification of rivers and other water bodies. There are several types of biological wastewater treatment devices: biofilters, biological ponds and aeration tanks.

IN biofilters wastewater is passed through a layer of coarse-grained material covered with a thin bacterial film. Thanks to this film, the processes of biochemical oxidation proceed intensively. They serve as the active principle in biofilters.

IN biological ponds all organisms inhabiting the reservoir participate in wastewater treatment.

Aerotanks - huge concrete tanks. The cleansing principle here is activated sludge from bacteria and microscopic animals. All these living creatures are developing rapidly, which is facilitated by the organic matter of sewage and the excess of oxygen entering the aerotanks with the flow of supplied air. Bacteria stick together into flakes and secrete enzymes that mineralize organic compounds. Silt with flakes quickly settles, separating from the purified water. Infusoria, flagellates, amoebae, rotifers and other smallest animals, devouring bacteria that do not stick together into flakes, rejuvenate the bacterial mass of sludge.

Before biological treatment, wastewater is subjected to mechanical treatment, and after it, to remove pathogenic bacteria, it is subjected to chemical treatment, chlorination with liquid chlorine or bleach. For disinfection, other physical and chemical methods are also used (ultrasound, electrolysis, ozonation, etc.).

biological method gives good results in the treatment of domestic wastewater. It is also used for cleaning waste from oil refineries, the pulp and paper industry, and the production of artificial fibers.

In the complex of tasks of water protection from pollution importance has their sanitary and hygienic condition. The water used for drinking must be harmless. Therefore, the biological, chemical and bacteriological state of water supply sources is under constant supervision.

Sources of water pollution, as already noted, are mainly industrial and partly domestic wastewater. The scale of sewage entering water bodies is increasing.

runoff quality on a number of rivers.

Circulating water supply is a significant reserve for saving water and keeping reservoirs clean. But it should be carried out while improving the technological processes of production, contributing to the reduction of harmful effluents.

Drain wastewater into water bodies, taking into account the sanitary and technical requirements for water quality, regulated by the Rules for the Protection of Surface Water from Pollution by Wastewater. In accordance with these Rules, the maximum allowable concentration (MPC) of impurities in water is considered to be such, at which its harmful effect on the human body is completely excluded, the smell, taste and color of water do not change. These requirements vary depending on the type of water use. The maximum permissible concentrations of harmful substances for drinking water bodies are many times less than for water bodies intended for swimming, recreation and industrial purposes.

Particular attention is paid to sources of drinking water supply. The current state standard in the Republic of Belarus ensures the high quality of drinking water. It must fully comply with MPC standards, do not contain pathogens, films, mineral oils. Drinking water must be treated at waterworks.

Control over the protection of water resources from pollution is carried out by several government agencies. They conduct state interdepartmental control over the use and protection of water resources from pollution and depletion. The main industrial, agricultural and municipal enterprises that discharge tens of millions of cubic meters of wastewater per day into water bodies were taken into account. At controlled facilities, the implementation of water protection measures is systematically checked, the composition of wastewater is analyzed, and measures are developed to improve the operation of existing treatment facilities.

The bodies of the sanitary and epidemiological service exercise control over the preservation of the purity of waters used as sources of drinking water supply, and reservoirs serving as objects of cultural and community use.

In the integrated protection of water resources, great importance is attached to saving clean water. To this end, they reduce the consumption rates for technological processes, introduce recycling water supply, fight against leakage, replace water cooling with air, etc. great attention they pay for the conservation of vegetation, the water protection value of which is great.

Water is one of the crop factors. In the conditions of irrigated agriculture, it is necessary to direct all means to saving it, to keep rivers and reservoirs clean. It is necessary to achieve an increase in the efficiency of irrigation systems, to combat seepage and other moisture losses. Important reserves for saving irrigation water are a further increase in crop yields, a reduction in water consumption per unit of plant mass, mechanization of irrigation.

To conserve water on non-irrigated lands, high agricultural technology is of particular importance. Autumn tillage and agroforestry measures contribute to the accumulation of moisture. Unfortunately, this feature of the water management balance of non-irrigated lands is often not taken into account when planning the use and protection of water resources. Meanwhile, an increase in the productivity of rainfed agriculture is associated with an increase in water consumption and a decrease in river runoff of surface origin.

Every year, the areas of irrigation systems using waste water (WWS) are expanding - specialized reclamation systems for receiving pre-treated waste water in order to use them for irrigation and fertilization of agricultural land, as well as post-treatment in natural conditions.

The impact of wastewater on natural complexes has not been studied enough. The main goal of the ongoing research is to establish the impact of these flows on the soil cover, natural waters, atmosphere, changes in the quality of agricultural products, human and animal health.

Most researchers believe that the decisive factor that excludes or weakens the negative impact of wastewater on environment, - irrigation mode. Ensuring the maximum efficiency of agricultural irrigation fields (AIF) as a water protection and reclamation measure (the presence of an irrigation network, drainage, buffer sites, forest plantations, etc.) largely depends on the culture of their operation and the degree of improvement.

In the conditions of extremely limited water resources of the arid zone, the use of household wastewater (WW) of cities for field fodder production on light soils of the WPO allows simultaneously solving a set of urgent problems: rational use water.

Under certain conditions, the use of high irrigation norms of wastewater is accompanied by the formation of a desalinated “spreading mound” of groundwater under the WPA and can cause secondary salinization of soils. Therefore, the need to build a drainage system is determined by the specific hydrogeological situation (the depth of the perch, the composition of water-bearing rocks, the conditions for the outflow of groundwater, etc.). Drainage water is sent for reuse at the ZPO.

Separate categories of wastewater, characterized by the complexity of the chemical composition, the presence of a number of toxic substances, are not used for irrigation of crops. Thus, chemically contaminated wastewater from the Volga Chemical Plant, after passing through mechanical and biological treatment systems, is directed to natural evaporation, which required the allocation of about 5,000 hectares of valuable agricultural land for the evaporator. The accumulation of large volumes of chemically polluted water poses a serious danger to the environment.

It is advisable to use such categories of wastewater for irrigation of tree plantations. The presence in these waters of residual substances that have cumulative and carcinogenic properties, in this case it does not matter, these plantings are not intended for food and feed purposes.

The most reliable and cost-effective method of sludge disposal is the use of SS as a fertilizer for crops, provided that the possibility of soil contamination must be excluded.

To preserve soil fertility, the volumes of traditional types of organic fertilizers are insufficient. Their deficit is especially great in suburban farms. According to most experts, the agricultural use of waste is one of the ways that will solve a number of problems: prevent pollution of the biosphere; eliminate the threat of fresh water shortage; to increase the production and use of organic fertilizers, to turn sewage treatment plants and waste processing plants into self-sustaining profitable enterprises.

The technology of sludge disposal at WWS is as follows. The sludge is fermented in digesters at a temperature of 50 "C, then it is dried on sludge pits. With this technological process, the water content in the sludge is reduced, its transportation is simplified and all helminths are practically destroyed, due to which, in terms of sanitary and hygienic terms, the sludge does not pose a danger when it is used as a fertilizer.The sediment dried on silt pits is stored in heaps, it has a moisture content of up to 50%, a dark or dark gray color, a specific smell.After appropriate analyzes for the presence of salts of heavy metals, it can be used as a fertilizer.According to the content of nitrogen, phosphorus, it superior to manure, but inferior to it in potassium content. Foreign experience indicates that 70-80% of sewage sludge the waters are coming for fertilizers, thus getting higher yields.

According to field experiments, when applying SS to the soil at a dose of 40–60 t/ha, the increase in spring wheat yield on leached chernozem ranges from 27.7 to 48.6%. The results of three-year vegetation experiments with corn, potatoes, tomatoes, Sudanese grass show that in the variants using pure precipitation and their mixtures with soil, the biomass of crops is 2-3 times higher than in the control. The results of the chemical analysis of agricultural crops grown on pure sludge show that the concentration of heavy metal salts in them does not exceed the maximum allowable norms and control indicators.

In order to avoid the negative aftereffect of precipitation and in order to limit the introduction of harmful compounds into the soil, the use of WWS in the same field is allowed no more than once every 5 years.

Insufficient study at the pre-project stage as a result of poor environmental training of specialists often leads to negative consequences, to imaginary savings. Here is an example. The state farm "Krasnodonsky" has a pig farm for 108 thousand heads (the largest in the Volgograd region). However, due to the fact that the design did not take into account the possibility of agricultural use of wastewater, the state farm does not have enough water and land resources to organize irrigation. Currently, there are only two irrigation lines with a total area of 505 hectares, which is clearly insufficient for the disposal of the entire volume of manure. Irrigation fields are under heavy load. In addition, the irrigation fields are not supplied with river water and are irrigated with manure without dilution. This poses a threat of contamination of soil, plants and groundwater.

Proved that chemical composition wastewater from complexes of large cattle allows using them for subsoil irrigation of alfalfa after preliminary clarification and threefold dilution. This leads to savings in mineral fertilizers and increases soil fertility.

The experience of developing sands in Syria, Libya, Algeria and other countries shows that when growing many fruit and agricultural crops on sands, water with a mineralization level of up to 10 g/l can be used. In some of these countries, due to the small supply of fresh water, which is also characteristic of the Caspian Sea, a law has been passed obliging farmers to mix fresh and mineral water for irrigation purposes. This allows more rational use of water resources. At the same time, in Israel and Algeria, irrigation on sandy lands is carried out by sprinkling and exclusively at night, which reduces evaporation processes, increases the productivity of photosynthesis and, in general, improves water consumption of plants.

Self-purification of water occurs not only in agricultural irrigation fields and filtration fields, but also in the riverbed itself. Biochemical and physico-chemical processes take place here, due to which the chemical and biological qualities of water are restored. Waste liquid and sewage, getting into reservoirs, are diluted with water. Part of the microbes settles to the bottom and is destroyed there. Pathogenic bacteria die under the influence of light, unfavorable temperature for them, and the bactericidal action of oxygen dissolved in water. A huge number of bacteria are devoured by unicellular protozoa, crustaceans and other zooplankton organisms.

The full flow and degree of pollution of any river largely depend on its tributaries. Small rivers are a kind of capillaries that feed large waterways and therefore require special care. An example of a master's attitude to small rivers is the experience of the Bryansk region. Dozens of rivers flow or originate here on its territory. Behind recent decades they got sloppy. In order to improve the health of these rivers and give them a second life, a set of measures has been developed and is being implemented. The destruction of vegetation along the banks of reservoirs is not allowed, the banks of rivers, gullies and ravines are being planted and fixed, the protection of reservoirs from pollution has been strengthened, and water-regulating dams are being built. Collective members of the Society for the Protection of Nature - collective farms and state farms - actively participate in the improvement of small rivers.

However, such an attitude towards small rivers is not shown everywhere. Coastal forests and shrubs are often cut down, which creates conditions for erosion. This is completely unacceptable, since floodplain forests, as water and soil protection, belong to the first category, where felling, except for sanitary felling, is prohibited.

eutrophication- eutrophication. Excess flow of organic and mineral substances into water bodies, preim. nitrogen and phosphorus. E. manifests itself with the active development of hydrophytes. During the mass extinction of algae, their decomposing remains are deposited in large quantities at the bottom of reservoirs, for the oxidation of which a large amount of oxygen is spent. Oxygen deficiency often leads to the death of fish and other hydrobionts.

The process of eutrophication of water bodies is the most studied. This natural process, characteristic of the entire geological past of the planet, usually proceeds very slowly and gradually, but in recent decades, due to the increased anthropogenic impact, the rate of its development has increased dramatically. Accelerated, or so-called anthropogenic eutrophication, is associated with the entry into water bodies of a significant amount of biogenic substances - nitrogen, phosphorus and other elements in the form of fertilizers, detergents, animal waste, atmospheric aerosols, etc. Under modern conditions, eutrophication of water bodies proceeds significantly shorter periods - several decades or less. Anthropogenic eutrophication has a very negative effect on freshwater ecosystems, leading to a restructuring of the trophic relationships of hydrobionts, a sharp increase in phytoplankton biomass due to the mass reproduction of blue-green algae, causing "blooming" of water, worsening its quality and living conditions of hydrobionts (moreover, emitting dangerous not only for aquatic organisms, but also toxins for humans). An increase in the mass of phytoplankton is accompanied by a decrease in the diversity of species, which leads to an irreplaceable loss of the gene pool, a decrease in the ability of ecosystems to homeostasis and self-regulation (Yablokov, 1983). The processes of anthropogenic eutrophication cover many large lakes of the world - the Great American Lakes, Balaton, Ladoga, Geneva, etc., as well as reservoirs and river ecosystems, primarily small rivers. On these rivers, in addition to the catastrophically growing biomass of blue-green algae, their banks are overgrown with higher vegetation. The blue-green algae themselves, as a result of their vital activity, produce the strongest toxins that are dangerous for hydrobionts and humans.

The Baltic Sea is vulnerable and faces many challenges. This summer, we once again had the opportunity to see how far the process of eutrophication of the Baltic Sea has gone, and the "bloom" of the water due to the massive development of blue-green algae is just one of good examples how serious the situation is. Other negative effects of eutrophication are manifested in a decrease in the transparency of sea water and a decrease in biological diversity. The diversity of life forms in the Baltic Sea is decreasing, because at the moment some parts of the seabed are dead, and some biotopes are completely destroyed. This, in turn, has led to a decrease in the number of populations of some species, while the number of others is increasing uncontrollably. The observed imbalance indicates that eutrophication is one of the most serious problems facing the natural component of the Baltic Sea.

Eutrophication, or eutrophication, is the process of enrichment of water bodies with nutrients, especially nitrogen and phosphorus, mainly of biogenic origin. As a result, the lake gradually overgrows and turns into a swamp filled with silt and decaying plant remains, which eventually dries up completely. Under natural conditions, this process takes tens of thousands of years, but as a result of anthropogenic pollution, it proceeds very quickly. So, for example, in small ponds and lakes, under the influence of man, it ends in just a few decades.

Eutrophication is enhanced when plant growth in a water body is stimulated by nitrogen and phosphorus found in fertilizer-laden runoff from agricultural land, cleaning and detergents, and other wastes. The waters of the lake that receives these effluents are a fertile environment in which there is a rapid growth of aquatic plants, occupying the space in which fish usually live. Algae and other plants, dying, fall to the bottom and are decomposed by aerobic bacteria that consume oxygen for this, which leads to the death of fish. The lake is filled with floating and attached algae and other aquatic plants, as well as small animals that feed on them. Blue-green algae, or cyanobacteria, make the water look like pea soup with a foul smell and fishy taste, and also cover the stones with a slimy film.

Eutrophication- an increase in the level of primary productivity of water bodies due to an increase in the concentration of biogenic substances in them, mainly nitrogen and phosphorus; often leads to blooming waters.

Eutrophication of water bodies

Once in natural water bodies (for example, phosphorus and nitrogen compounds), biogenic elements become a breeding ground for microorganisms, including blue-green algae. The waste products of blue-greens are allergens, toxins that have a direct effect on humans. Algae breed especially intensively in well-heated water, that is, in summer. That is why some of us find red spots on our bodies after swimming in the bay. And if you drink such water, even if it is boiled, you can get very poisoned. The process of anthropogenic eutrophication, causing rapid and sometimes irreversible disruption of the functional relationships of the ecosystem, leads to a deterioration in water quality, undermining useful productivity, and sometimes to a complete loss of the natural resources of the lake. The main negative consequences of this process are the massive development of planktonic algae, the appearance of an unpleasant odor and taste of water, an increase in the content of organic substances, a decrease in transparency and an increase in the color of water. Supersaturation of water with organic matter stimulates the development of saprophytic bacteria, including pathogens, as well as aquatic fungi. As a result of the vital activity of some algae, especially blue-green ones, toxic effects occur, leading to diseases in animals, and in some cases in humans (“Gaff” and “Sartland” diseases).

A significant part of the dissolved oxygen contained in lake water is consumed for the oxidation of a huge amount of newly formed organic matter. As a result, commercially valuable fish species (salmon, whitefish), demanding high water quality, are being replaced by low-grade species that are less sensitive in this respect.

"Water Bloom"- mass development (outbreak) of phytoplankton, causing a change in water color from green (green and blue-green algae) and yellow-brown (diatoms) to red (dinoflagellates). The intensity of this process is determined by the biomass of algae: weak (0.5 - 0.9 mg / l), moderate (1 - 9.9 mg / l), intensive (10 - 99.9 mg / l) and "hyperbloom" - more than 100 mg/l.

These phenomena have been known since ancient times, but recently they have become frequent and very intense as a result of the increased anthropogenic impact on marine ecosystems. This is mainly due to the significant intake of organic substances (nitrogen, phosphorus, potassium, etc.)

This leads to a deterioration of the oxygen regime (up to freezes), to the accumulation of toxic organic compounds in the aquatic environment, which causes the appearance of red tides in the seas.

Eutrophication(eutrophication, eutrophication) - an increase in the biological productivity of water bodies as a result of the accumulation of biogenic substances in water under the influence of natural and mainly anthropogenic factors. The main reasons are the influx of huge amounts of biogenic components (especially nitrogen and phosphorus), which are supplied to the environment by agricultural production (the use of fertilizers), as well as various detergents (more than 30 million tons of soap are used annually in the world), etc.

According to B. Henderson-Sellers, the main criteria for characterizing the process of eutrophication of water bodies are: - a decrease in the concentration of dissolved oxygen in water; - increase in the content of biogenic components; - increase in the content of suspended particles, especially of organic origin; - successive change of algae populations with a predominance of blue-green and green; - increase in water turbidity (reduction of light penetration); - a significant increase in phytoplankton biomass (with a simultaneous decrease in species diversity), etc. . Eutrophication processes have covered many large freshwater reservoirs in the USA and Canada (Great American Lakes), Japan, Europe (Lake Geneva, Ladoga, Onega, Balaton, etc.), as well as many marine basins (Mediterranean, Black, Baltic, etc.). Since the eutrophication of water bodies has become a serious global environmental problem, UNESCO has begun work on monitoring inland waters and controlling the eutrophication of the world's water bodies.

red tide - an environmental phenomenon caused by the excessive discharge of organic matter into the ocean and mass outbreak pyrophytic algae. Studies have shown that after heavy rains, a large amount of nutrients (especially nitrogen and phosphorus) are washed off the coasts and at the same time the influx of fresh water lowers the salinity of the ocean, and the rise of deep water brings additional organic substances to the surface, which stimulate the growth and mass reproduction of pyrophytic algae. . All this leads to great economic losses, as the beaches are empty, which are covered with a mass of decaying fish. In recent years, in the World Ocean, as a result of the release of a huge amount of organic matter, red tides have become more frequent, which are observed off the coast of India, Australia, Japan, Scandinavia, in the Black and mediterranean seas. In this regard, it is necessary to organize monitoring of the content of toxic species of phytoplankton in the ocean waters, causing eutrophication and red tides.

Negative environmental consequences of eutrophication of water bodies

EUTROPHICATION PROCESSES IN THE VOLGOGRAD RESERVOIR AND WAYS TO PREVENT THEM

eutrophication processes

in the Volgograd reservoir

and ways to prevent them

Mamontova A.S. (PR-051), Shepeleva E.S. (Assistant of the Department of E&P), Supervisor – Novikov V.V., Candidate of Agricultural Sciences, Associate Professor

Volga Humanitarian Institute (branch) VolSU

In the lake section of the Volgograd reservoir with stagnant zones, the processes of overgrowing with aquatic vegetation (eutrophication) are intensifying, which is the reason for the deterioration of water quality and depletion of the species composition of the ecosystem. Eutrophication leads to the development of blue-green algae Cyanophyta, which cause the "bloom" of water, worsening its quality. Therefore, this problem is relevant for the city of Volzhsky, which draws water from the Volgograd reservoir.

To combat blue-green algae, modern methods of biological, physical and chemical treatment of surface waters are used, as well as the method of algolization - the introduction of a unicellular green algae - chlorella, which exhibits antagonism to blue-green algae. The latter method is used in the Volgograd branch of GosNIORKh, whose scientists have shown an improvement in the state of the reservoir (Fig. 1).

The above method is being tested on the Volgograd and Tsimlyansk reservoirs, where positive results have been obtained. In the future, with the confirmation of positive results, it is planned to be widely used in the reservoirs of the Volga-Kama cascade, including the Kuibyshev reservoir and other reservoirs, where this problem also exists.

The purpose of our work was to trace the dynamics of the water bloom of the Volgograd reservoir in connection with the ongoing algolization.

During the period greatest development biomass of blue-green algae, we took samples of phytoplankton at 73 points of the Volgograd reservoir in July 2006 and 2007. and analyzed in the ecological educational laboratory of VGI VolSU according to GOST 17.1.4.02 - 90.

The content of chlorophyll A in the samples varied from 0.95 µg/l in the upper reaches of Pichuga Bay to 8.87 µg/l in the middle of the dam area. In a number of bays and sections in 2007, the level of biomass decreased compared to 2006. However, in the dam area, on the contrary, an increase in the level of biomass was observed. This trend can be traced in 2007-2008 as well. (Fig. 2). In a number of bays - Erzovka, Dubovka, where the anthropogenic impact is especially high, an increase in biomass is noted.

III. Aquatic ecosystems.

Limiting factors of aquatic ecosystems:

1. Salinity - the content of soluble salts, mainly sodium chloride, in the water mass;

2. Depth of penetration of sunlight;

3. The amount of oxygen;

4. Availability of nutrients;

5. Water temperature.

According to the degree of water salinity, aquatic ecosystems are divided into two large classes.

brackish(Marine) Freshwater

Oceans - lakes, reservoirs

Mouths of rivers (estuaries) - ponds

Coastal marshes - swamps

Coral reefs - rivers and streams (watercourses)

main areas of the ocean.

In any of the oceans of the globe, two main zones can be distinguished: coastal and open ocean.

Eutrophication 5

The mechanism of the impact of eutrophication on ecosystems of water bodies 10

Conclusion 12

List of sources used 14

Introduction

The theme of the control work is formulated as: "Eutrophication of water bodies." I believe that it is most relevant today, since the pollution of aquatic ecosystems poses a great danger to all living organisms and, in particular, to humans.

In my work, I want to consider this term "eutrophication", as well as the mechanism of its impact on the ecosystems of water bodies.

Eutrophication (Greek eutrophia - good nutrition) - enrichment of rivers, lakes and seas with nutrients, accompanied by an increase in the productivity of vegetation in water bodies. The main chemical elements contributing to eutrophication are phosphorus and nitrogen. It is the main part of the natural process called succession. In a few thousand years, the lake can change naturally and turn from oligotrophic to eutrophic, or, in other words, “grow old”. However, anthropogenic activities lead to similar consequences in just a few decades. Therefore, it is customary to talk about anthropogenic eutrophication, contrasting it with natural.

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

Eutrophication - good example the fact that not all negative problems of our time are associated with the industrial release of "toxic" compounds, because in this case, the cause is often the entry into the natural ecosystem of such "harmless" substances as soil particles and nutrients. On the this example it is clearly seen that a change in any environmental factor can upset the balance in the ecosystem.

Eutrophication

Eutrophication creates acute economic and environmental problems. Clean water is essential for many industrial processes, people and livestock, commercial and sport fishing, resort operations and navigation.

Eutrophic water bodies are characterized by rich littoral and sublittoral vegetation and abundant plankton. Artificially unbalanced eutrophication can lead to the rapid development of algae (“blooming” of waters), oxygen deficiency, and the death of fish and animals. This process can be explained by the low penetration of sunlight into the depths of the reservoir (due to phytoplankton on the surface of the reservoir) and, as a result, the lack of photosynthesis in bottom plants, and hence oxygen. one

Typical "oxygen depletion" curves: the effect of organic matter discharge into the river on the concentration of dissolved oxygen in water.

The life cycle of phytoplankton is very short. Its rapid reproduction is compensated by death, leading to the accumulation of detritus. Dead phytoplankton enters the deep zone, where decomposers feed on it, which also consume oxygen and reduce its concentration in the water. When there is no dissolved oxygen left, decomposer bacteria survive by anaerobic fermentation, and this can continue as long as there is detritus to feed on.
Thus, near the surface, the amount of dissolved oxygen can be very high due to phytoplankton photosynthesis, while at depth its reserves are depleted by decomposers.

The “rain” of phytoplankton transfers the biogenic elements assimilated by them to the bottom, where, as the detritus decomposes, they are released again. Ascending convective currents return nutrients to the surface, and the described process is repeated many times. 2 A natural reservoir is a biologically balanced ecological system tuned to self-purification and self-healing. This natural state of the biological balance of a closed or low-flowing reservoir: a pond, a lake, can be disturbed both as a result of the natural aging of the reservoir, the accumulation of natural organic matter in the reservoir: foliage, branches, excrement of fish and waterfowl, dead aquatic plants, and as a result of intense pollution reservoir with organic substances and nutrients (biogenic) elements: garbage, storm sewage, sediment from fields and roads, poorly treated wastewater, sewage, fertilizers in abundance deliver organic matter to the reservoir. 3

As already mentioned in the introduction, eutrophication is the process of enrichment of water bodies with nutrients, especially nitrogen and phosphorus, mainly of biogenic origin. As a result, the lake gradually overgrows and turns into a swamp filled with silt and decaying plant remains, which, in the end, completely dries up. Under natural conditions, this process takes tens of thousands of years, but as a result of anthropogenic pollution, it proceeds very quickly. So, for example, in small ponds and lakes, under the influence of man, it ends in just a few decades.

Anthropogenic eutrophication of water bodies caused by: discharges of nutrients (primarily phosphates), changes in the hydrological regime (the rate of water flow in reservoirs slows down; when the level of lakes falls, nutrients are mobilized from bottom sediments), washout of the surface layer of soil, etc. Anthropogenic eutrophication of water bodies leads, as a rule, to a violation of biological balance: the algal flora (species composition of algae) changes, and the density of algae populations changes. The population density of mixotrophic species increases sharply. The density of green algae populations is declining. Later, when these species die off, the oxygen content decreases, and the content of hydrogen sulfide increases. In addition, a number of algae release toxins that directly kill aquatic organisms. 4

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

Non-anthropogenic eutrophication of water bodies observed when the direction of sea currents changes, with seasonal changes in illumination and temperature. Notorious are the "red tides" (rapid reproduction of pyrophytic algae), which lead to the accumulation of toxins in the tissues of mollusks and other aquatic organisms. This leads to the mass death of these organisms and to food poisoning of the population that eats these organisms. five

Eutrophication is enhanced when plant growth in a water body is stimulated by nitrogen and phosphorus found in fertilizer-laden runoff from agricultural land, cleaning and detergents, and other wastes. The waters of the lake that receives these effluents are a fertile environment in which there is a rapid growth of aquatic plants, occupying the space in which fish usually live. Algae and other plants, dying, fall to the bottom and are decomposed by aerobic bacteria that consume oxygen for this, which leads to the death of fish. The lake is filled with floating and attached algae and other aquatic plants, as well as small animals that feed on them. Blue-green algae, or cyanobacteria, make the water look like pea soup with a bad smell and fishy taste, and also cover the stones with a slimy film. The main anthropogenic sources of phosphorus and nitrogen are untreated wastewater (especially from livestock farms) and fertilizer runoff from fields. Many countries have banned the use of sodium orthophosphate in laundry detergents to reduce eutrophication of water bodies. 6

Pollution of a reservoir first of all negatively affects the key element of the biological balance and self-purification of the reservoir - the composition of the useful microflora of the reservoir (biocenosis). The number of beneficial microorganisms in 1 ml. polluted water is sharply reduced, depleted and their species composition changes, at the same time, potentially dangerous microorganisms functioning at + 30-37 C are actively developing in dirty water, thus microbial and other types of self-purification are suppressed by pollution.

Due to the insufficiency of our knowledge about the patterns of eutrophication and its nature, the methods used to combat this phenomenon are still imperfect. Copper sulphate, some pesticides, coagulants, polyacrylamide used for these purposes are toxic to fish and aquatic organisms, therefore, they cannot be recommended for combating water bloom in fisheries.

The most expedient is the collection of blue-green algae by sucking them from the surface layers of water using floating pumping units and transporting the mass to filtration fields or to sedimentation pools. Once freed from excess water, they can be used as fertilizers in agriculture.

The mechanism of the impact of eutrophication on ecosystems of water bodies

The mechanism of the impact of eutrophication on the ecosystems of water bodies:

1. An increase in the content of biogenic elements in the upper water horizons causes the rapid development of plants in this zone (primarily phytoplankton, as well as fouling algae) and an increase in the number of zooplankton feeding on phytoplankton. As a result, the transparency of water rarely decreases, the depth of penetration of sunlight decreases, and this leads to the death of bottom plants from lack of light. After the death of bottom aquatic plants, it is the turn of the death of other organisms for which these plants create habitats or for which they are an upstream link in the food chain.

2. Plants that multiply strongly in the upper water horizons (especially algae) have a much larger total body surface and biomass. At night, photosynthesis does not occur in these plants, while the respiration process continues. As a result, in the early morning hours of warm days, oxygen in the upper water horizons is practically exhausted, and the death of organisms living in these horizons and demanding oxygen content is observed (the so-called “summer freeze” occurs).

4. In the bottom soil, devoid of oxygen, anaerobic decay of dead organisms occurs with the formation of such strong poisons as phenols and hydrogen sulfide, and such a powerful "greenhouse gas" (in its effect in this regard that is 120 times superior to carbon dioxide) as methane. As a result, the process of eutrophication destroys most of the flora and fauna of the reservoir, almost completely destroying or very strongly transforming its ecosystems, and greatly worsens the sanitary and hygienic qualities of its water, up to its complete unsuitability for swimming and drinking water supply. 7

Conclusion

When presenting the material in my work, I tried to give the most detailed concept of "eutrophication of water bodies". This issue was considered, as far as possible, in sufficient detail. On this issue, we can formulate brief conclusions:

Eutrophication- (from the Greek eutrophia - good nutrition), an excessive increase in the content of nutrients in water bodies, accompanied by an increase in their productivity. It represents a change from a rich ecosystem based on benthic vegetation to a simple one based on phytoplankton.

On geological time scales, reservoirs are constantly enriched with biogens and filled with sediments coming from land. Over many centuries, silt and detritus accumulate in the lake, gradually filling the initially deep bowl of the lake.

In this work, the types of eutrophication were also noted:

Anthropogenic eutrophication of water bodies

Non-anthropogenic eutrophication of water bodies

In paragraph 2 of the work, the mechanism of the impact of eutrophication on the ecosystems of water bodies was considered.

Thus, summing up, we can say that the violation or distortion of the mechanisms of self-purification of water bodies leads to eutrophication (bogging) and degradation of the water body - a gradual change in the types of aquatic ecosystems, when each subsequent type of ecosystem is a more primitive model compared to the previous one. To save and restore the reservoir, it is necessary to intensively clean the water and bottom sediments from decaying organic matter and biogenic elements, restore the oxygen regime and the mechanisms of biological self-purification of the reservoir. The fight against pollution of the reservoir, eutrophication, massive growth of blue-green algae, mud, duckweed should not be considered separately from the purification of the reservoir from organic and biogenic pollution, restoration of biological balance and self-purification.

List of sources used

Ecology and economics of environmental management: Textbook for universities / Ed. prof. E.V. Girusov, prof.V.N. Lopatina, - 2nd ed., revised. and additional -M.: UNITY-DANA, Unity, 2003. - 519s

Wikipedia: http://ru.wikipedia.org/wiki/Eutrophication

Eutrophication of water bodies. Ecology of Russia: http://www.eco-net.ru/content/evtrofikacija-vodoemov

Ecological biotechnology: http://www.microzym.ru/pondtreatment.htm

Electronic ecological dictionary

Algae: http://afonin-59-bio.narod.ru/4_evolution/4_evolution_self/es_13_algy.htm

Biodiversity - Eutrophication: http://www.biodiversity.ru/coastlearn/bio-rus/boxes/eutro.html

1 http://ru.wikipedia.org/wiki/Eutrophication

2 http://www.eco-net.ru/content/evtrofikacija-vodoemov

3 http://www.microzym.ru/pondtreatment.htm

4 Electronic ecological dictionary

5 http://afonin-59-bio.narod.ru/4_evolution/4_evolution_self/es_13_algy.htm

6 Ecology and economics of environmental management: Textbook for universities / Ed. prof. E.V. Girusov, prof.V.N. Lopatina, - 2nd ed., revised. and additional -M.: UNITY-DANA, Unity, 2003. - 519s

7 http://www.biodiversity.ru/coastlearn/bio-rus/boxes/eutro.html

On the Diploma work >> Ecology

dumping them in reservoirs without prior purification are harmful impact on the water of the latter. In... farms and food industries. Mechanism impact eutrophication on the ecosystems reservoirs next. 1. Increasing the content of nutrients ...

Eutrophication is the saturation of a reservoir with biologically active elements that are not characteristic of its ecosystem. Unfortunately, the time has come when environmentalists have to sound the alarm and call for water purification in order to save all the species living in this world.

people and planet

Man is the only living being on Earth who could not establish harmonious relations with her. If you carefully study the emergence and development of each species, you can trace how they either adapted to the conditions of the planet or disappeared from its face, and only a person decided that the existence was created exclusively for him, and exploited it for his own purposes. Today's generation sees how people disposed of the awareness of their superiority over other living beings. Flowering reservoirs, dead seas, advancing deserts - this is only a small fraction of what mankind has done during its existence.

The greatest damage to nature was inflicted in the 20th century, and it was caused by the development of such industries as:

The chemical industry, which has taken a leading place in the food, textile, engineering, pharmaceutical, agricultural and many other industries.
Land reclamation, in which the improper distribution of water resources, the construction of dams and other structures led to violations of the usual ecosystem of water bodies. Often the result of this is subsequent eutrophication (this is the enrichment or poisoning of water with elements that are not characteristic of its composition). So it was with the Aral Sea, when in the 60s of the last century, due to the extremely high water intake from the Amu Darya and Syr Darya, which feed it, it became shallow by 13 meters. How the Aral Sea looks today is known to all ecologists of the world.
The electrification of the country, carried out in the 30s of the XX century, also became the cause of the subsequent eutrophication of water bodies, as it led to the construction of artificial reservoirs. Cut off by a dam from the main river flow, they blocked the movement of water and natural spawning grounds for fish, which disrupted the ecosystem of the rivers, and subsequent stocking of fish could not change much.

Man has not become "friends" with the planet, since only a small part of people are aware of the scale of the global catastrophe and are members of parties and organizations involved in protecting the environment.

The water space of the planet

The concept of the hydrosphere includes the waters of both the World Ocean and water bodies located on land. Among the latter are not only swamps, lakes and rivers, but also the glaciers of the mountains, Antarctica, Greenland and groundwater.

Most of the water is concentrated in the seas and oceans (94%) in a liquid or solid state. The remaining 6% is in land waters. The fact that the entire hydrosphere of the planet is a single whole that cannot be violated is evidenced by the commonality of its waters:

Through atmospheric vapors and the water cycle in nature, they can communicate with each other.
The surface of the World Ocean is almost the same in its level.
The composition of the water of the seas and oceans on Earth is almost identical and consists of 35% salts, giving it a bitter-salty taste.

Since everything on the planet to one degree or another contains liquid in its composition, its significance in the ecosystem is the most important: no water - no life. This is evidenced by deserts, some of which were previously the bottom of the ocean.

It would be strange to hope that the “reversal of the rivers”, which they tried to carry out in the USSR for the sake of the industrialization of the country, or emissions chemical waste in other countries will not entail the consequences that manifested themselves in the form of natural disasters in different regions peace. The reasons for the eutrophication of the oceans today are just the result of what mankind has done in the 20th century.

Important: such games of "gods", when people violate the planet's ecosystem for their own profit, concern not only its hydrosphere. Deforestation in the Amazon has led to the formation of ozone holes in the atmosphere and climate change throughout the Earth.

Unfortunately, humanity has not understood that the entire ecological system of the planet is a single organism, consisting of millions of elements, each of which is important for overall survival. Attempts to stop the eutrophication of water bodies today are pathetic attempts to return them to their original state, similar to what was created by nature itself.

Abiotic constituents of water

It is not only a habitat for millions of living organisms, but also a solar energy accumulator due to its properties:

Its density is 800 times higher than that of air, and its viscosity is 55 times higher.
Water has the highest level of heat capacity, which affects the formation of the climate on Earth.
Water masses, due to their movement in space (circulation in nature), maintain their chemical and physical composition.
Abiotic factors also include temperature changes (warming level) depending on the depth of water bodies.
The degree of saturation of water with oxygen depends on the survival of breathing organisms in it.
Acidity is also an important indicator, since the inhabitants of reservoirs, accustomed to and surviving at one of its levels, die if its indicator changes in one direction or another.
The transparency of the water surface determines the depth of its light regime.

Important: the last factor affects the development, photosynthesis and distribution of green microorganisms, phytoplankton, organic nutrients and the level of their accumulation.

The process of eutrophication of water bodies starts if one or several abiotic factors are disturbed. Let us assume that the reason for the death of living organisms in it is associated with the turbidity of water, caused by an increase in the amount of mineral and organic substances in it, delivered to it by industrial effluents. To change this, it is necessary to eliminate the cause that caused the turbidity (shut off the flow), after which the water is purified, followed by its saturation with substances and organisms characteristic of its ecosystem.

Eutrophication is the certain death of all living creatures, not only in water, but also in the surrounding area. Since coastal animals and plants directly depend on the cleanliness of the surrounding water area, which is not only their home, but also a feeding and breeding area, their habitat disappears with its destruction.

Mutual activity of living organisms in water

Over millions of years of life on this planet, close relationships have arisen between its inhabitants, violating which you can destroy not just one kind of animal, but an entire ecosystem. Such fluctuations in one direction or another always cause a response from nature. Take, for example, the island of St. Helena, whose forests were almost completely destroyed by goats brought here at the beginning of the 16th century. Together with them, animals and birds - endemic to this place - died out. The same picture can be observed on some islands in Oceania.

It is not always possible to see such obvious changes in water in time, because the reasons for the accelerated eutrophication of water bodies are not always obvious. For example, washing away the upper layers of soil fertilized with organic matter during floods does not seem dangerous until the lake or river blooms and the fish floats belly up.

The need for cleaning appears when there is a violation biotic factors characteristic of the area. These phenomena mean the relationship of living organisms living in a reservoir, which are divided into indirect and direct. The first includes factors on which their life activity does not directly depend. For example, algae are not food for some organisms, but their presence in a reservoir affects the saturation of water with oxygen, which they need.

Direct dependence is when the connection between them is so close that it is enough for one link in the food chain to disappear in order for several species associated with it to be destroyed at once. For example, an oil spill in the ocean causes the death of plankton, the disappearance of which leads to starvation of many organisms for which it is food.

Such natural disasters cause eutrophication of this area of water. To restore the former balance, it is necessary to create a favorable environment for the growth and reproduction of plankton at the place of its death - this is an extremely long and expensive process that could have been avoided if people had used the power of wind, sun or tides as fuel, and not natural resources.

The structure of the oceans

Both terrestrial land and water bodies are divided into natural areas, each of which is characterized by a separate ecosystem. It is known that the inhabitants of the seas, rivers and lakes live at different depths, forming "communities", which include both the simplest microorganisms and plants, fish and animals.

Each tier has its own temperature regime, the level of saturation of water with oxygen and light, and its inhabitants do not leave their territory, being an integral part of its inherent environment. So the inhabitants of the depths do not survive, rising to the surface of the water, the same happens with those who leave their zone and sink to the bottom.

In the event that any component of such a tier is violated, all its inhabitants receive damage. For example, even a slight increase in ocean water temperature by long time leads to bleaching and death of coral reefs, along with which their inhabitants die. The vacated space is occupied by algae, which leads to a complete replacement of the existing ecosystem, which, as a rule, cannot be restored. This applies not only to corals, but also to the inhabitants of fresh water bodies, which are dying out due to the rapid bloom of algae.

Scientists believe that eutrophication is the most fast way ecosystem disturbance, but far from the only one. There are several types of water pollution, after some of which it is not subject to subsequent recovery, because it is not enough to “feed” water bodies with the necessary microorganisms and bioactive elements. Efforts are required to restore their living conditions, taking into account all biotic and abiotic factors which is extremely difficult to do.

Types of biological pollution

If it takes 8-10 days to naturally clean the atmosphere, then it will take 2500 years for the World Ocean, polluted groundwater can become cleaner in 1400 years, for a lake this period is at least 17-20 years, and for rivers - up to 20 days. That is why it is so important to prevent water eutrophication.

If the volume of the World Ocean decreases on the planet, then a person will face the same gradual extinction as marine life. The Earth's climate will change forever, leading to the onset of the desert, and, as apocalyptic authors show their readers, water will cost more than a human life.

There are several reasons for eutrophication of water bodies:

biological pollution;
chemical change in the composition of water;
physical pollution.

Most nutrients enter water bodies through industrial effluents and municipal sewers, and into groundwater with rain and decomposition elements in food waste dumps. Farming is especially damaging. For example, a livestock fattening complex alone with up to 10,000 livestock produces the same amount of biogenic waste per year as a city with a population of 100,000.

No less harm is caused by organic and mineral fertilizers washed off the fields by rains. All this leads to an accelerated enrichment of water with bioactive elements, and the first signs of eutrophication appear in the form of the growth of blue-green algae and their rapid reproduction. After a while, the entire reservoir is filled with their flowering, which causes the burning of oxygen and the complete destruction of all life in it.

Such anthropogenic eutrophication is not caused by contamination with toxic waste, but by an increase in seemingly safe nutrients in the composition of water, which leads the area to a state of ecological disaster with all the ensuing consequences: the destruction of flora and fauna, an increase in such diseases among people as cholera, hepatitis and intestinal diseases. infections.

Types of chemical pollution

The greatest danger is the contamination of water with lead, mercury or salts of other heavy metals, which leads to eutrophication of lakes and rivers, on the banks of which there are industrial enterprises. Oil and derivatives from it cause no less harm. Pollution of the seas and oceans by them for a year is estimated at 10 million tons, and today the total coverage area is 1/5 of the Earth's water surface.

Important: 10 m 2 of oil film on the surface of the water causes death not only of organisms living in the affected area, but also of animals and birds living within it.

Another source that causes eutrophication is nitrates and phosphates, 1 mg/l of which destroys plankton, and 5 mg/l leads to the death of fish.

Since the defeat of water bodies by chemicals causes the inhibition of all natural biological processes in them, such situations are also called environmental disasters that lead to the death of the environment.

Types of physical water pollution

Another way to influence water is to physically change its properties. Hunting within water bodies has a particularly strong effect on its composition. Scientists have calculated that a million hunters who have fired just one shot release more than 30 tons of lead into the water, resulting in its eutrophication.

No less harm is caused by the heating of the surface of reservoirs of warm water discharged into them by the waste heat and power plant. At the same time, its saturation with oxygen gradually decreases, and in return the number of pathogens increases, which leads to the complete destruction of life in the infection zone.

The consequences of eutrophication of water bodies are the most deplorable. As a rule, their restoration requires a lot of efforts and financial investments, since it includes not only water purification and reproduction of the former ecosystem in it, but also putting the entire territory adjacent to it in order. Only in highly developed countries there are special legal regulations and money in the budget.

What to do?

To date, there are many ways to kill all life in the oceans, but there are only two ways to fix everything:

Destroying algae plantations, which in turn will lower the dissolved oxygen in the water.
Eliminate the causes of eutrophication.

The implementation of these measures requires the adoption of appropriate laws, the development of long-term programs and financial investments. If this is not done today, then subsequent generations of people will live in a world described by many science fiction writers.

Tragedy on a global scale

Awareness of the magnitude of the ecological catastrophe and its consequences is the primary task of the governments of all countries on the planet. Returning nature to its originality is much more difficult than destroying it, therefore people, who are an integral part of the Earth's unified ecosystem, must take full responsibility for what is happening in the world, only after that changes for the better are possible.