The negative impact of transport on the environment. The impact of transport on the environment (2) - Abstract What are the features of the negative impact on the atmosphere of transport

Introduction

pollution emission gas motor vehicle

A powerful source of environmental pollution is road transport. Exhaust gases contain an average of 4 - 5% CO, as well as unsaturated hydrocarbons, lead compounds and other harmful compounds.

The close proximity of the road adversely affects the components of agrophytocenosis. The practice of agriculture still does not fully take into account the impact of such a powerful anthropogenic factor on field crops. Pollution of the environment with toxic components of exhaust gases leads to large economic losses in the economy, since toxic substances cause disturbances in plant growth and reduce quality.

The exhaust gases of internal combustion engines (ICE) contain about 200 components. According to Yu. Yakubovsky (1979) and E.I. Pavlova (2000) the average composition of exhaust gases from spark ignition and diesel engines are as follows: nitrogen 74 - 74 and 76 - 48%, O 2 0.3 - 0.8 and 2.0 - 18%, water vapor 3.0 - 5.6 and 0.5 - 4.0%, CO 2 5.0 - 12.0 and 1.0 - 1.0%, nitric oxide 0 - 0.8 and 0.002 - 0.55%, hydrocarbons 0.2 - 3.0 and 0.009 - 0.5%, aldehydes 0 - 0.2 and 0.0001 - 0.009%, soot 0 - 0.4 and 0.001 - 1.0 g/m 2, benz (a) pyrene 10 - 20 and up to 10 mcg / m 3respectively.

On the territory of the SHPK "Rus" there is a federal highway "Kazan - Yekaterinburg". During the day, a large number of vehicles pass along this road, which are a source of constant environmental pollution with exhaust gases from internal combustion engines.

The purpose of this work is to study the impact of transport on the pollution of natural and artificial phytocenoses of the SHPK "Rus" in the Perm Territory, located along the federal highway "Kazan - Yekaterinburg".

Based on the goal, the following tasks were set:

• according to literary sources, to study the composition of exhaust gases of internal combustion engines, the distribution of emissions from motor vehicles; to study the factors influencing the distribution of exhaust gases, the influence of the components of these gases on roadside sections;
• to investigate the intensity of car traffic on the federal highway "Kazan - Yekaterinburg";
• calculate vehicle emissions;
• take soil samples and determine the agrochemical indicators of roadside soils, as well as the content of heavy metals;
• determine the presence and species diversity of lichens;
• to identify the effect of soil pollution on the growth and development of radish plants of the rose-red variety with a white tip;
• determine the economic damage from vehicle emissions.

The material for the thesis was collected during the industrial practice in the village. Bolshaya Sosnova, Bolshesosnovsky district, SHPK "Rus". The studies were carried out in 2007-2008.

1. The impact of motor transport on the state of the environment (literature review)

1.1 Factors affecting the spread of exhaust gases

The issue of the influence of factors contributing to the spread of exhaust gases of internal combustion engines (ICE EG) was studied by V.N. Lukanin and Yu.V. Trofimenko (2001). They found that the level of ground concentration of harmful substances in the atmosphere from vehicles with the same mass emission can vary significantly depending on technogenic and natural and climatic factors.

Technogenic factors:intensity and volume of exhaust gas (EG) emissions, the size of the territories where pollution is carried out, the level of development of the territory.

Natural and climatic factors:characteristics of the circular regime, thermal stability of the atmosphere, atmospheric pressure, air humidity, temperature regime, temperature inversions and their frequency and duration; wind speed, frequency of air stagnation and weak winds, fog duration, terrain relief, geological structure and hydrogeology of the area, soil and plant conditions (soil type, water permeability, porosity, granulometric composition, soil cover erosion, vegetation condition, rock composition, age, bonitet ), the background value of indicators of pollution of natural components of the atmosphere, the state of the animal world, including the ichthyofauna.

In the natural environment, the air temperature, speed, strength and direction of the wind are constantly changing, so the spread of energy and ingredient pollution occurs in constantly changing conditions.

V.N. Lukanin and Yu.V. Trifomenko (2001) established the relationship between the change in the concentration of nitrogen oxides and the distance from the road and the direction of the wind: when the wind had a direction parallel to the road, the highest concentration of nitrogen oxide was observed on the road itself and within 10 m from it, and its distribution to longer distances occurs in smaller concentrations compared to the concentration on the road itself; if the wind is perpendicular to the road, then the nitric oxide distance occurs over long distances.

Higher surface temperatures during the day cause the air to rise upwards, resulting in additional turbulence. Turbulence is a vortex chaotic movement of small volumes of air in the general wind flow (Chirkov, 1986). At night, the ground temperature is cooler, so turbulence is reduced, so exhaust gas dispersion is reduced.

The ability of the earth's surface to absorb or radiate heat affects the vertical distribution of temperature in the surface layer of the atmosphere and leads to temperature inversion. Inversion is an increase in air temperature with altitude (Chirkov, 1986). An increase in air temperature with height leads to the fact that harmful emissions cannot rise above a certain ceiling. For a surface inversion, the repeatability of the heights of the upper boundary is of particular importance, for an elevated inversion, the repeatability of the lower boundary.

A certain potential for self-healing of environmental properties, including air purification, is associated with the absorption of up to 50% of natural and man-made CO2 emissions by water surfaces. 2 to the atmosphere.

The most deeply studied issue of the influence on the propagation of exhaust gases of internal combustion engines V.I. Artamonov (1968). Various biocenoses play an unequal role in cleaning the atmosphere from harmful impurities. One hectare of forest produces gas exchange 3-10 times more intense than field crops occupying a similar area.

A.A. Molchanov (1973), studying the issue of the impact of the forest on the environment, noted in his work the high efficiency of the forest in cleaning the environment from harmful impurities, which is partly associated with the dispersion of toxic gases in the air, since in the forest the air flow over uneven tree crowns contributes to the change the nature of the flows in the very part of the atmosphere.

Tree plantations increase air turbulence, create an increased displacement of air currents, as a result of which pollutants disperse more quickly.

Thus, the distribution of exhaust gases of internal combustion engines is influenced by natural and man-made factors. The most priority natural factors include: climatic, soil orographic and vegetation cover. A decrease in the concentration of harmful emissions from vehicles in the atmosphere occurs in the process of their dispersion, sedimentation, neutralization and binding under the influence of abiotic factors of biota. ICE exhaust gases are involved in environmental pollution at the global, regional and local levels.

1.2 Contamination of roadside soils with heavy metals

Anthropogenic load during technogenic intensification of production causes soil pollution. The main pollutants are heavy metals, pesticides, oil products, toxic substances.

Heavy metals are metals that cause soil pollution by chemical indicators - lead, zinc, cadmium, copper; they enter the atmosphere and then into the soil.

Motor transport is one of the sources of heavy metal pollution. Heavy metals get on the soil surface, and their further fate depends on chemical and physical properties. Soil factors that significantly influence are: soil granulometric composition, soil reaction, organic matter content, cation exchange capacity, and drainage (Bezuglova, 2000).

An increase in the concentration of hydrogen ions in the soil solution led to the transition of poorly soluble lead salts into more soluble salts. Acidification reduces the stability of lead-humus complexes. The pH value of a buffer solution is one of the most important parameters that determines the amount of sorption of heavy metal ions in the soil. With an increase in pH, the solubility of most heavy metals increases and, consequently, their mobility in the solid phase soil-solution system. Studying the mobility of cadmium in aerobic soil conditions, it was found that in the pH range of 4-6, the mobility of cadmium is determined by the ionic strength of the solution, at pH more than 6 sorption by manganese oxides acquires leading importance.

Soluble organic compounds form only weak complexes with cadmium and affect its sorption only at pH 8.

The most mobile and plant-accessible part of the heavy metal compounds in the soil is their content in the soil solution. The amount of metal ions entering the soil solution determines the toxicity of the element in the soil. The state of equilibrium in the system solid phase - solution determines the sorption processes, the nature and direction depends on the composition and properties of soils.

Liming reduces the mobility of heavy metals in the soil and their entry into plants (Mineev, 1990; Ilyin, 1991).

The maximum permissible concentration (MAC) of heavy metals should be understood as such concentrations that, with prolonged exposure to the soil and the growth of plants on it, do not cause any pathological changes or anomalies in the course of biological soil processes, and also do not lead to the accumulation of toxic elements. in agricultural crops (Alekseev, 1987).

The soil, as a component of the natural complex, is extremely sensitive to pollution by heavy metals. According to the danger of impact on living organisms, heavy metals are in second place after pesticides (Perelman, 1975).

Heavy metals enter the atmosphere with vehicle emissions in slightly soluble forms: - in the form of oxides, sulfides and carbonates (in the series cadmium, zinc, copper, lead - the proportion of soluble compounds increases from 50 - 90%).

The concentration of heavy metals in soils increases year by year. Compared to cadmium, lead in soils is associated mainly with its mineral content (79%) and forms less soluble and less mobile forms (Obukhov, 1980).

The level of roadside soil pollution by vehicle emissions depends on the traffic intensity of vehicles and the duration of road operation (Nikiforova, 1975).

Two zones of accumulation of transport pollution in roadside soils have been identified. The first zone is usually located in the immediate vicinity of the road, at a distance of up to 15–20 m, and the second at a distance of 20–100 m; a third zone of anomalous accumulation of elements in soils may appear, located at a distance of 150 meters from the road (Golubkina, 2004).

The distribution of heavy metals over the soil surface is determined by many factors. It depends on the characteristics of pollution sources, meteorological features of the region, geochemical factors and landscape conditions.

Air masses dilute emissions and carry particulate matter and aerosols over distances.

Airborne particles are dispersed in the environment, but most of the unrestricted lead is deposited on the ground in the immediate vicinity of the road (5-10 m).

Soil pollution is caused by cadmium contained in vehicle exhaust gases. In soils, cadmium is an inactive element, so cadmium contamination persists for a long time after the cessation of fresh intake. Cadmium does not bind to humic substances in the soil. Most of it in soils is represented by ion-exchange forms (56-84%), therefore this element is actively accumulated by the terrestrial parts of plants (the absorption of cadmium increases with soil acidification).

Cadmium, like lead, has a low solubility in soil. The concentration of cadmium in the soil does not cause changes in the content of this metal in plants, since cadmium is poisonous and living matter does not accumulate it.

On soils contaminated with heavy metals, a significant decrease in yield was observed: grain crops by 20-30%, sugar beets by 35%, potatoes by 47% (Kuznetsova, Zubareva, 1997). They found that crop depression occurs when the cadmium content in the soil becomes more than 5 mg/kg. At a lower concentration (within 2 mg/kg), only a downward trend in yield is observed.

V.G. Mineev (1990) notes that the soil is not the only link in the biosphere from which plants draw toxic elements. Thus, atmospheric cadmium has a large share in various cultures, and, consequently, in its absorption by the human body with food.

Yu.S. Yusfin et al. (2002) proved that zinc compounds accumulate in barley grain near the highway. Investigating the ability of legumes to accumulate zinc in the area of ​​highways, they found that the average concentration of the metal in the immediate vicinity of the highway is 32.09 mg/kg of air-dry mass. With distance from the route, the concentration decreased. The greatest accumulation of zinc at a distance of 10 m from the road was observed in alfalfa. And the leaves of tobacco and sugar beet almost did not accumulate this metal.

Yu.S. Yusfin et al. (2002) also believe that soil is more susceptible to heavy metal contamination than the atmosphere and aquatic environment, since it does not have such property as mobility. The levels of heavy metals in soils depend on the redox and acid-base properties of the latter.

When snow melts in spring, there is some redistribution of the components of GO fallout in the biocenosis, both in the horizontal and vertical directions. The distribution of metals in the biocenosis depends on the solubility of the compounds. This issue was studied by I.L. Varshavsky et al. (1968), D.Zh. Berinya (1989). The results obtained by them give some ideas about the total solubility of metal compounds. So, 20-40% of strontium, 45-60% of cobalt, magnesium, nickel, zinc compounds and more than 70% of lead, manganese, copper, chromium and iron in precipitation are in a sparingly soluble form. Easily soluble fractions were in the largest quantities in the zone up to 15 m from the roadbed. The easily soluble fraction of elements (sulphur, zinc, iron) tends to settle not near the road itself, but at some distance from it. Easily soluble compounds adsorb into plants through the leaves, enter into exchange reactions with the soil-absorbing complex, and sparingly soluble compounds remain on the surface of plants and soil.

Soils contaminated with heavy metals are the source of their entry into groundwater. Research I.A. Shilnikov and M.M. Ovcharenko (1998) showed that soils polluted with cadmium, zinc, lead are cleared by natural processes (harvest removal and leaching with infiltration waters) very slowly. The introduction of water-soluble salts of heavy metals increased their migration only in the first year, but even in this it was insignificant in quantitative terms. In subsequent years, water-soluble salts of heavy metals are transformed into less mobile compounds, and their leaching from the root layer of soils sharply decreases.

Pollution of plants with heavy metals occurs in a fairly wide band - up to 100 meters or more from the roadbed. Metals are found in both woody and herbaceous vegetation in mosses and lichens.

According to Belgian data, the degree of metal pollution in the environment is in direct proportion to the intensity of traffic on the roads. So, with a traffic flow intensity of less than 1 thousand and more than 25 thousand cars per day, the concentration of lead in the leaves of plants of roadside areas is 25 and 110 mg, respectively, iron - 200 and 180, zinc - 41 and 100, copper - 5 and 15 mg /kg dry weight of leaves. The greatest soil contamination is observed near the roadway, especially on the dividing strip, and as it moves away from the roadway, it gradually decreases (Evgeniev, 1986).

Settlements can be located near the road, which means that the action of the ICE exhaust gas will affect human health. The effect of OG components was considered by G. Fellenberg (1997). Carbon monoxide is dangerous to humans, primarily because it can bind to blood hemoglobin. The content of CO-hemoglobin exceeding 2.0% is considered harmful to human health.

According to the effect on the human body, nitrogen oxides are ten times more dangerous than carbon monoxide. Nitrogen oxides irritate the mucous membranes of the eyes, nose, and mouth. Inhalation with air of 0.01% oxides for 1 hour can cause serious illness. A secondary reaction to the effects of nitrogen oxides is manifested in the formation of nitrites in the human body and their absorption into the blood. This causes the conversion of hemoglobin to metahemoglobin, which leads to a violation of cardiac activity.

Aldehydes irritate all mucous membranes and affect the central nervous system.

Hydrocarbons are toxic and have an adverse effect on the human cardiovascular system. Hydrocarbon compounds of GO, in particular benz (a) pyrene, have a carcinogenic effect, that is, they contribute to the emergence and development of malignant tumors.

The accumulation of cadmium in the human body in excess amounts leads to the emergence of neoplasms. Cadmium can cause loss of calcium by the body, accumulating in the kidneys, bone deformity and fractures (Yagodin, 1995; Oreshkina, 2004).

Lead affects the hematopoietic and nervous systems, the gastrointestinal tract and the kidneys. Causes anemia, encephalopathy, mental retardation, nephropathy, colic, etc. Copper in excess amounts in the human body leads to toxicosis (gastrointestinal disorders, kidney damage) (Yufit, 2002).

Thus, the exhaust gases of internal combustion affect crops, which are the main component of the agricultural system. The impact of exhaust gases ultimately leads to a decrease in the productivity of ecosystems, a deterioration in the presentation and quality of agricultural products. Some components of GO can accumulate in plants, which creates an additional hazard to human and animal health.

1.3 Composition of exhaust gases

The number of various chemical compounds present in vehicle emissions is about 200 items, which include compounds that are very dangerous for human health and the environment. At present, during the combustion of 1 kg of gasoline in a car engine, more than 3 kg of atmospheric oxygen is almost irretrievably consumed. One passenger car emits about 60 cm into the atmosphere every hour 3exhaust gases, and cargo - 120 cm 3(Drobot et al., 1979).

It is almost impossible to accurately determine the amount of harmful emissions into the atmosphere by engines. The amount of emissions of harmful substances depends on many factors, such as: design parameters, the processes of preparation and combustion of the mixture, the mode of operation of the engine, its technical condition, and others. However, based on data on the average statistical composition of the mixture for certain types of engines and the corresponding values ​​of emissions of toxic substances per 1 kg of fuel consumed, knowing the consumption of individual types of fuel, it is possible to determine the total emission.

SOUTH. Feldman (1975) and E.I. Pavlova (2000), the exhaust gases of internal combustion engines were combined into groups according to the chemical composition and properties, as well as the nature of the impact on the human body.

First group. It includes non-toxic substances: nitrogen, oxygen, water vapor, and other natural components of atmospheric air.

Second group. This group includes only one substance - carbon monoxide, or carbon monoxide (CO). Carbon monoxide is formed in the engine cylinder as an intermediate product of the transformation and decomposition of aldehydes. Lack of oxygen is the main cause of increased carbon monoxide emissions.

Third group. It contains nitrogen oxides, mainly NO - nitric oxide and NO 3- nitrogen dioxide. Nitrogen oxides are formed as a result of a reversible thermal oxidation reaction of nitrogen in the air under the action of high temperature and pressure in the engine cylinders. Of the total amount of nitrogen oxides, the exhaust gases of gasoline engines contain 98 - 99% of nitrogen oxides and only 1 - 2% of nitrogen dioxide, in the exhaust gases of diesel engines - approximately 90% and 10%, respectively.

Fourth group. This group, the most numerous in composition, includes various hydrocarbons, that is, compounds of type C X H at . The exhaust gases contain hydrocarbons of various homologous series: alkanes, alkenes, alkadienes, cyclanes, as well as aromatic compounds. The mechanism of formation of these products can be reduced to the following stages. In the first stage, the complex hydrocarbons that make up the fuel are decomposed under the action of thermal processes into a number of simple hydrocarbons and free radicals. In the second stage, under conditions of oxygen deficiency, atoms are split off from the formed products. The resulting compounds combine with each other into more and more complex cyclic, and then into polycyclic structures. Thus, at this stage, a number of polycyclic aromatic hydrocarbons, including benzo(a)pyrene, arise.

Fifth group. It consists of aldehydes - organic compounds containing an aldehyde group associated with a hydrocarbon radical. I.L. Warsaw (1968), Yu.G. Feldman (1975), Yu. Yakubovsky (1979), Yu.F. Gutarevich (1989), E.I. Pavlova (2000) found that out of the sum of aldehydes, exhaust gases contain 60% formaldehyde, 32% aliphatic aldehydes, and 3% aromatic aldehydes (acrolein, acetaldehyde, acetaldehyde, etc.). The largest amount of aldehydes is formed at idle and low loads, when the combustion temperatures in the engine are low.

Sixth group. It includes soot and other dispersed particles (engine wear products, aerosols, oils, soot, etc.). SOUTH. Feldman (1975), Yu. Yakubovsky (1979), E.I. Pavlova (2000), note that soot is a product of cracking and incomplete combustion of fuel, contains a large amount of adsorbed hydrocarbons (in particular, benzo (a) pyrene), so soot is dangerous as an active carrier of carcinogens.

Seventh group. It is a sulfur compound - inorganic gases such as sulfur dioxide, which appear in the composition of the exhaust gases of engines if fuel with a high sulfur content is used. Significantly more sulfur is present in diesel fuels compared to other types of fuels used in transport (Varshavsky 1968; Pavlova, 2000). The presence of sulfur increases the toxicity of diesel exhaust gases and is the cause of the appearance of harmful sulfur compounds in them.

Eighth group. The components of this group - lead and its compounds - are found in the exhaust gases of carburetor vehicles only when using leaded gasoline, which has an additive that increases a dangerous octane number. The composition of the ethyl liquid includes an antiknock agent - tetraethyl lead Pb (C 2H 5)4. during the combustion of leaded gasoline, the scavenger helps to remove lead and its oxides from the combustion chamber, turning them into a vapor state. They, together with the exhaust gases, are released into the surrounding space and settle near the road (Pavlova, 2000).

Under the influence of diffusion, harmful substances spread into the atmosphere, enter into the processes of physical and chemical effects between themselves and with the components of the atmosphere (Lukanin, 2001).

All pollutants are divided according to the degree of danger:

Extremely hazardous (tetraethyl lead, mercury)

Highly hazardous (manganese, copper, sulfuric acid, chlorine)

Moderately hazardous (xylene, methyl alcohol)

Low-hazard (ammonia, fuel gasoline, kerosene, carbon monoxide, etc.) (Valova, 2001).

The most toxic to living organisms are carbon monoxide, nitrogen oxides, hydrocarbons, aldehydes, sulfur dioxide and heavy metals.

1.4 Mechanisms of pollution transformation

IN AND. Artamonov (1968) revealed the role of plants in the detoxification of harmful environmental pollutants. The ability of plants to purify the atmosphere from harmful impurities is determined, first of all, by how intensively they absorb them. The researcher assumes that the pubescence of plant leaves, on the one hand, helps to remove dust from the atmosphere, and on the other hand, it inhibits the absorption of gases.

Plants detoxify harmful substances in various ways. Some of them are bound by the cytoplasm of plant cells and become inactive due to this. Others are converted in plants to non-toxic products, which are sometimes included in the metabolism of plant cells and used for plant needs. It is also found that the root systems emit some harmful substances absorbed by the above-ground part of the plants, such as sulfur-containing compounds.

IN AND. Artamonov (1968) notes the importance of green plants, which lies in the fact that they carry out the process of utilization of carbon dioxide. This is due to a physiological process that is characteristic only of autotrophic organisms - photosynthesis. The scale of this process is evidenced by the fact that during the year plants bind in the form of organic substances about 6-7% of the carbon dioxide contained in the Earth's atmosphere.

Some plants are highly gas-absorbing and at the same time are resistant to sulfur dioxide. The driving force behind the uptake of sulfur dioxide is the diffusion of molecules through the stomata. The more pubescent the leaves, the less they absorb sulfur dioxide. The intake of this phytotoxicant depends on the humidity of the air and the saturation of the leaves with water. If the leaves are moist, they absorb sulfur dioxide several times faster than dry leaves. Air humidity also affects this process. At a relative air humidity of 75%, bean plants absorbed sulfur dioxide 2-3 times more intensively than plants growing at a humidity of 35%. In addition, the rate of absorption depends on the illumination. In the light, elm leaves absorbed sulfur 1/3 faster than in the dark. Absorption of sulfur dioxide is related to temperature: at a temperature of 32 O This gas was intensively absorbed from the bean plant compared to the temperature of 13 o C and 21 O WITH.

The sulfur dioxide absorbed by the leaves is oxidized to sulfates, due to which its toxicity is sharply reduced. Sulfate sulfur is included in the metabolic reactions occurring in the leaves, it can partially accumulate in plants without the occurrence of functional disorders. If the rate of intake of sulfur dioxide corresponds to the rate of its transformation by plants, the effect of this compound on them is small. The root system of plants can remove sulfur compounds into the soil.

Nitrogen dioxide can be taken up by the roots and green shoots of plants. Uptake and conversion of NO 2leaves occurs at a high speed. The nitrogen recovered by the leaves and roots is then incorporated into amino acids. Other nitrogen oxides are dissolved in the water contained in the air, and then absorbed by plants.

The leaves of some plants are able to absorb carbon monoxide. Assimilation and transformation of it occurs both in the light and in the dark, however, in the light these processes are carried out much faster, as a result of primary oxidation, carbon dioxide is formed from carbon monoxide, which is consumed by plants during photosynthesis.

Higher plants are involved in the detoxification of benzo(a)pyrene and aldehydes. They metabolize benzo(a)pyrene through roots and leaves, converting it into various open chain compounds. And aldehydes undergo chemical transformations in them, as a result of which the carbon of these compounds is included in the composition of organic acids and amino acids.

The seas and oceans play a huge role in sequestering carbon dioxide from the atmosphere. IN AND. Artamonov (1968) in his work describes how this process occurs: gases dissolve better in cold water than in warm water. For this reason, carbon dioxide is intensively absorbed in cold areas, and precipitates in the form of carbonates.

Particular attention to V.I. Artamonov (1968) focused on the role of soil bacteria in the detoxification of carbon monoxide and benzo(a)pyrene. Soils rich in organic matter show the highest CO-binding activity. Soil activity increases with temperature, reaching a maximum at 30 O C, temperature above 40 O C contributes to the release of CO. The scale of absorption of carbon monoxide by soil microorganisms is estimated differently: from 5-6 * 10 8t/year up to 14.2*10 9t/year. Soil microorganisms break down benzo(a)pyrene and convert it into various chemical compounds.

V.N. Lukanin and Yu.V. Trofimenko (2001) studied the mechanisms of transformation of ICE exhaust gas components in the environment. Under the influence of transport pollution, changes in the environment can occur at the global, regional and local levels. Such road pollutants as carbon dioxide, nitrogen oxides are "greenhouse" gases. The mechanism of the "greenhouse effect" is as follows: solar radiation reaching the Earth's surface is partially absorbed by it, and partially reflected. Some of this energy is absorbed by "greenhouse" gases, water vapor and does not pass into outer space. Thus, the global energy balance of the planet is disturbed.

Physical and chemical transformations in local territories. Such harmful substances as carbon monoxide, hydrocarbons, oxides of sulfur and nitrogen, spread in the atmosphere under the influence of diffusion and other processes and enter into processes of physical and chemical interaction between themselves and with the components of the atmosphere.

Some processes of chemical transformations begin immediately from the moment emissions enter the atmosphere, others - when favorable conditions appear for this - the necessary reagents, solar radiation, and other factors.

Carbon monoxide in the atmosphere can be oxidized to carbon dioxide in the presence of impurities - oxidizing agents (O, O 3), oxide compounds and free radicals.

Hydrocarbons in the atmosphere undergo various transformations (oxidation, polymerization), interacting with other pollutants, primarily under the influence of solar radiation. As a result of these reactions, pyroxides are formed. Free radicals, compounds with oxides of nitrogen and sulfur.

In a free atmosphere, sulfur dioxide after some time is oxidized to SO 3or interacts with other compounds, in particular hydrocarbons, in the free atmosphere during photochemical and catalytic reactions. The end product is an aerosol or solution of sulfuric acid in rainwater.

Acid precipitation falls on the surface in the form of acid rain, snow, fog, dew, and is formed not only from sulfur oxides, but also nitrogen oxides.

Nitrogen compounds released into the atmosphere from transport facilities are mainly represented by nitrogen oxide and nitrogen dioxide. When exposed to sunlight, nitric oxide is rapidly oxidized to nitrogen dioxide. The kinetics of further transformations of nitrogen dioxide is determined by its ability to absorb ultraviolet rays and dissipate into nitric oxide and atomic oxygen in the processes of photochemical smog.

Photochemical smog is a multiple mixture of gases and aerosol particles of primary and secondary origin. The composition of the main components of smog includes ozone, nitrogen and sulfur oxides, numerous organic peroxide compounds, collectively called photooxides. Photochemical smog occurs as a result of photochemical reactions under certain conditions: the presence in the atmosphere of a high concentration of nitrogen oxides, hydrocarbons and other pollutants; intense solar radiation and calm or very weak air exchange in the surface layer with a powerful and increased inversion for at least a day. Sustained calm weather, usually accompanied by inversions, is necessary to create a high concentration of reactants. Such conditions are created more often in June-September and less often in winter. In prolonged clear weather, solar radiation causes the breakdown of nitrogen dioxide molecules with the formation of nitric oxide and atomic oxygen. Atomic oxygen with molecular oxygen give ozone. It would seem that the latter, oxidizing nitric oxide, should again turn into molecular oxygen, and nitric oxide into dioxide. But that doesn't happen. The nitric oxide reacts with the olefins in the exhaust gases, which break down the double bond to form molecular fragments and excess ozone. As a result of the ongoing dissociation, new masses of nitrogen dioxide are split and give additional amounts of ozone. A cyclic reaction occurs, as a result of which ozone gradually accumulates in the atmosphere. This process stops at night. In turn, ozone reacts with olefins. Various peroxides are concentrated in the atmosphere, which in total form oxidants characteristic of photochemical fog. The latter are the source of what are called free radicals, which are reactive.

Pollution of the earth's surface by transport and road emissions accumulates gradually and persists for a long time even after the elimination of the road.

A.V. Staroverova and L.V. Vashchenko (2000) studied the transformation of heavy metals in soil. They found that heavy metals that got into the soil, primarily their mobile form, undergo various transformations. One of the main processes affecting their fate in the soil is fixation with humic matter. Fixation is carried out as a result of the formation of salts of heavy metals with organic acids. Adsorption of ions on the surface of organic colloidal systems or their complexing with humic acids. At the same time, the migration possibilities of heavy metals decrease. This is what largely explains the increased content of heavy metals in the upper, that is, the most humus layer.

The components of the exhaust gases of internal combustion engines, entering the environment, undergo transformation under the influence of abiotic factors. They can break down into simpler compounds, or, interacting with each other, form new toxic substances. Plants and soil bacteria also participate in the transformation of GO, which include toxic components of GO in their metabolism.

Thus, it should be noted that the contamination of phytocenoses with various pollutants is ambiguous and needs further study.

2. Place and methods of research

.1 Geographic location of SHPK "Rus"

Agricultural production cooperative "Rus" is located in the north-eastern part of the Bolshesonovsky district. The central estate of the economy is located in the village of Bolshaya Sosnova, which is the regional center. The distance from the center of the cooperative to the regional center is 135 km, the railway station is 34 km. Communication within the farm is carried out on roads with asphalt, gravel and dirt roads.

2.2 Natural and climatic conditions

The land use of the cooperative is located in the southwestern agro-climatic zone. This zone is favorable for agricultural crops in terms of heat balance and the length of the growing season, but there is a danger of the upper soil horizon drying out in spring due to soil evaporation.

The territory of the cooperative belongs to the western foothills of the Urals. The geomorphological region is the eastern branch of the Verkhnekamsk Upland. The relief of the SHPK "Rus" is represented by the Ocher and Sosnovka watersheds. The watershed is divided by the blast furnaces of the rivers But and Melnichnaya, Chernaya into watersheds of the second order, the provision of the economy with water is sufficient.

The results of economic activity are greatly influenced by economic conditions: the location of the economy, the availability of land, labor resources, and means of production.

The sum of positive air temperatures, with temperatures above 10 O C is 1700-1800 O , HTC = 1.2. The amount of precipitation during the growing season is 310 mm. The duration of the frost-free period is 111-115 days, it starts from May and ends on September 10-18. Summer is moderately warm, the average monthly air temperature in July is + 17.9 O C. winter is cold, the average monthly temperature in January is 15.4 O C. The average height of snow cover in the fields is 50-60 cm.

This area is located in a zone of sufficient moisture. During the year precipitation falls 475 - 500 mm. The reserves of productive moisture in the soil during the sowing of early spring crops are sufficient, optimal and amount to about 150 mm in a meter layer, which makes it possible to cultivate spring and winter cereals and perennial grasses in this area with the correct use of agricultural technology.

Type of water regime - washing. The significance of climate as a factor in soil formation is determined by the fact that the influx of water into the soil is associated with climate.

The soil cover of the territory of the economy is very diverse and finely contoured, which explains the heterogeneity of the relief, soil-forming rocks, and vegetation. The most common soils on the farm are soddy-podzolic, occupying an area of ​​4982 hectares or 70% of the entire territory of the farm. The predominant among them are sod-shallow - and fine podzolic. Somewhat less common are sod-weakly podzolic and sod-deep-podzolic.

The territory of the economy is located in the forest zone, in the subzone of mixed forests, in the region of the southern taiga, fir-spruce forests with small-leaved species and linden in the tree layer.

The most common species are: fir, spruce, birch, aspen. In the undergrowth are found along the edges: mountain ash, bird cherry. In the shrub layer - wild rose, honeysuckle. The grassy cover in the forests is represented by herbs: forest geranium, raven eye, hoof, high wrestler, common gout, marsh marigold and numerous cereals - timothy, bent grass.

Natural fodder lands are represented by continental upland and lowlands, as well as floodplain meadows of high and low levels. Continental upland meadows with normal moisture and atmospheric precipitation have grass-forb, forb-grass vegetation. It consists of the following species: cereals - meadow bluegrass, mouse peas, red clover; forbs - yarrow, nivyanik, caustic ranunculus, large rattle, strawberries, horsetail, sprawling bell.

Meadow productivity is low. Feeding value is average, due to the large amount of undernourished forbs.

Lowland meadows are located in the valleys of small rivers, streams with moisture due to atmospheric and groundwater. They are dominated by a grass-forb type of vegetation with a dominance of meadow fescue, cocksfoot, soft bedstraw, common cuff, yarrow.

The use of these types of land - as pastures, hayfields. Floodplain meadows of a high level are represented by forb-grass-legume vegetation.

Abundantly found: meadow bluegrass, fescue, cocksfoot, couch grass. The productivity of these meadows is average, the fodder value is good, they are convenient for use for hayfields.

The main part of the territory is occupied by agricultural crops, most of which are perennial grasses and cereals.

The fields of the state farm are littered, mostly with perennial weeds. Of the rhizomatous species, horsetail, coltsfoot, couch grass, creeping wheatgrass, of root shoots: field sow thistle, field bindweed, of annuals: spring - shepherd's purse, beautiful pikulnik, wintering: blue cornflower, odorless chamomile.

2.3 Characteristics of the economic activity of SHPK "Rus"

SHPK "Rus" is one of the largest farms in the Bolshesosnovsky district. For more than a decade, the farm has been steadily engaged in agricultural activities, the main directions of which are elite seed production and dairy breeding.

The total land area of ​​the cooperative is 7114 hectares, including agricultural land 4982 hectares, of which arable land 4548 hectares, hayfields 110 hectares, pastures 324 hectares. For three years, the cooperative has used the land in various ways. A slight decrease in the used lands occurs from their cooperative members - shareholders.

The main direction of the livestock industry is the cultivation of cattle for meat and milk production.

Animal husbandry is the main direction for obtaining animal feed.

The main part of the grown products of the farm is used as feed, part remains for seeds, and a very small part remains for sale. Grain for sale can only be sold for fodder purposes, because it is low in protein and fiber, it has a high moisture content, and therefore it is not profitable to grow grain for sale.

There is enough forage on the farm. Hay, silage, green mass are used as feed. Oats and clover are used for green mass. Silage is prepared from clover and oats, hay from clover and forbs and cereal grasses on natural hayfields. Straw is not used for livestock feed, as there is enough fodder.

Over the past three years, complex fertilizers, as well as phosphorus, potash, and organic fertilizers, have been introduced on the territory of the SHPK Rus.

Manure is stored in open-air manure storages. Pesticides are used little, carried by hang gliders, not stored.

Agricultural machinery imported. For the storage of fuel, lubricating oils, there is a gas station - a gas station, which is located outside the settlement. It is fenced, green embankment is made to prevent the flow of melt and rain water, as well as spilled fuel from the territory of the gas station.

2.4 Objects and methods of research

The studies were carried out in 2007-2008. The objects of study are phytocenoses located along the highway of the federal highway "Ekaterinburg - Kazan", belonging to the SHPK "Rus" of the Bolshesonovskoye district. Experience options - distance from the road: 5 m, 30 m, 50 m, 100 m, 300 m.

In the Bolshesonovsky region, the prevailing winds blow in a south-westerly direction, so the ICE exhaust gas is transferred to the study area. Due to the low speed and strength of the wind, subsidence occurs near the federal highway.

To study the impact of vehicles on the roadside sections of the federal highway, the following methods were used:

Determining the traffic intensity of motor vehicles on the federal highway.

The intensity of the traffic flow was determined by the method of Begma as presented by A.I. Fedorova (2003). Previously, the entire traffic flow was divided into the following groups: light trucks (this included trucks with a carrying capacity of up to 3.5 tons), medium trucks (with a carrying capacity of 3.5 - 12 tons), heavy trucks (with a carrying capacity of more than 12 tons).

The counting was carried out in autumn (September) and spring (May) for 1 hour in the morning (from 8 to 9 a.m.) and in the evening (from 19 to 20 p.m.). The repetition was 4-fold (weekdays) and 2-fold (weekends).

Determination of agrochemical indicators and the content of mobile forms of heavy metals in the soil.

Sampling was carried out at a distance of 5 m, 30 m, 50 m, 100 m and 300 m from the road. At these distances, samples were taken in four replicates. Soil samples for determining agrochemical indicators were taken to the depth of the arable layer, for determining heavy metals to a depth of 10 cm. The weight of each soil sample was about 500 g.

Chemical analysis was carried out in the laboratory at the Department of Ecology, PGSHA. From agrochemical indicators, the following was determined: humus content, pH, content of mobile forms of phosphorus; of heavy metals, mobile forms of cadmium, zinc, and lead were identified in the soil.

· pH of the salt extract according to the TsINAO method (GOST 26483-85);

· mobile compounds of phosphorus by the photometric method according to Kirsanov (GOST 26207-83);

Determination of phytotoxicity

The method is based on the reaction of test cultures. This method makes it possible to reveal the toxic effect of heavy metals on the development and growth of plants. The experiment was carried out in four repetitions. As a control, soil soil based on biohumus, purchased in a store, was used with agrochemical indicators: nitrogen not less than 1%, phosphorus not less than 0.5%, potassium not less than 0.5% on dry matter, pH 6.5-7, 5. 250 g of soil is placed in the vessels, and it is moistened to 70% of the PV, and this humidity is maintained throughout the entire experiment. 25 radish seeds (Rose-red with a white tip) are sown in each vessel. On the fourth day, the vessels are placed on a light rack with illumination for 14 hours a day. Radishes were grown under these conditions for two weeks.

During the experiment, observations are made according to the following indicators: the time of emergence of seedlings and their number per day are recorded; evaluate the overall germination (by the end of the experience); measure regularly the length of the ground mass (plant height). At the end of the experiment, the plants are carefully separated from the ground, tapped, the remnants of the soil are shaken off and the final length of the above-ground part of the plants, the length of the roots, is measured. Then the plants are dried in air and the biomass of the above-ground parts and roots is weighed separately. Comparison of these data makes it possible to reveal the fact of phytotoxicity or stimulating action (Orlov, 2002).

The phytotoxic effect can be calculated according to different indicators.

FE = M To - M Hm To *100,

where M To - weight of the control plant (or all plants per vessel);

M X is the mass of plants grown on a presumably phytotoxic medium.

Lichen indication was carried out according to the method of Shkraba (2001).

The determination of lichens is carried out on trial sites. At each site, at least 25 mature trees of all species represented in the forest stand are taken into account.

The palette is made from a transparent two-liter bottle of 10-30 cm, on which a grid is drawn with a sharp object through each centimeter. First, the total coverage is calculated, i.e. the area occupied by all types of lichens, and then, the coverage of each individual lichen species is determined. The amount of coverage using a grid is determined by the number of grid squares in which lichens occupy more than half of the area of ​​the square (a), conditionally attributing to them a coverage equal to 100%. Then count the number of squares in which lichens occupy less than half the area of ​​the square (b), conditionally attributing to them a coverage equal to 50%. The total projective cover (K) is calculated by the formula:

K \u003d (100 a + 50 b) / C,

where C is the total number of grid squares (Pchelkin, Bogolyubov, 1997).

After determining the total coverage, the coverage of each lichen species presented on the accounting site is established in the same way.

3. Research results

.1 Characteristics of the intensity of traffic on the federal highway

From the results obtained, we can conclude that the intensity of vehicles for the autumn and spring periods is different, and the intensity also changes during the working and weekend days, depending on the time of day. In the autumn, 4080 cars pass through a 12-hour working day, and in the spring 2448 cars, i.e. 1.6 times less. In autumn, 2880 units of vehicles pass through a 12-hour day off, in spring 1680 units, i.e. 1.7 times less. In autumn, the average for 1 hour of the working day of light freight transport is 124 units, in the spring 38, which is 3.2 times less. The number of heavy freight transport in the spring decreased, and in the autumn it increased.

In autumn, on a day off, passenger vehicles increased by 1.7 times in 1 hour. In the spring on a working day, the average freight transport increased by 1.8 times. The average number of cars per day in autumn was 120 units, in spring - 70, which is 1.7 times less.

The intensity of vehicles on the federal highway is greater per day in the autumn period than in the spring. The highest intensity of medium freight transport was observed in the spring period on working days, and in autumn on a day off. The intensity of passenger car traffic in autumn on a working day is 1.6 times higher than in spring, and on weekends it is 1.7 times less than in autumn. Heavy trucks are observed more on weekdays in autumn, and in spring - on weekends. Buses run the most in autumn.

The ratio of the number of road transport on different days and seasons is shown in Figures 1.2.

Rice. 1 The ratio of the number of vehicles,% (autumn)

Rice. 2 The ratio of the number of vehicles,% (spring)

In the autumn on working days, the first place in the traffic flow is occupied by cars (47.6%), the second place is light trucks (34.9%), then heavy trucks (12%), medium trucks (3.36%) and buses ( 1.9%). In autumn, on weekends, the number of cars was (48.9%), light trucks - 31.5%, medium trucks - 9.9%, heavy trucks - 7.3% and buses - 2.1%. During the spring period (working days) passenger vehicles - 48.7%, heavy trucks - 20.2%, light trucks - 18.4%, medium trucks - 10.6%, buses - 1.9%. And on weekends, passenger vehicles make up 48.1%, medium and heavy trucks - 7%, and 18%, respectively, light trucks - 25% and buses - 1.5%.

3.2 Characteristics of motor transport emissions of the federal highway

Analyzing the data on vehicle emissions (Appendix 1,2,3,4) and tables 2,3,4,5,6, we can draw the following conclusions: in the autumn period for a 12-hour working day on the Kazan-Yekaterinburg federal highway 1 km is emitted: carbon monoxide - 30.3 kg, nitrogen oxides - 5.06 kg, hydrocarbons - 3.14 kg, soot - 0.13 kg, carbon dioxide - 296.8 kg, sulfur dioxide - 0.64 kg; for a 12-hour day off: carbon monoxide - 251.9 kg, nitrogen oxides - 3.12 kg, hydrocarbons - 2.8 kg, soot - 0.04 kg, carbon dioxide - 249.4 kg, sulfur dioxide - 0 .3 kg.

Analysis of data for the spring period shows that on a working day, the following pollution is formed per 1 km of the federal highway: carbon monoxide - 26 kg, nitrogen oxides - 8.01 kg, hydrocarbons - 4.14 kg, soot - 0.13 kg, carbon dioxide - 325 kg, sulfur dioxide - 0.60 kg. On a day off: carbon monoxide - 138.2 kg, nitrogen oxides - 5.73 kg, hydrocarbons - 3.8 kg, soot - 0.08 kg, carbon dioxide - 243 kg, sulfur dioxide - 8 kg.

It can be said that of all six components in the exhaust gas of the internal combustion engine, carbon dioxide prevails in terms of the amount of carbon dioxide, its largest amount is observed in autumn on a working day. Also during this period, the largest amount of carbon monoxide, nitrogen oxides and hydrocarbons is observed, and the smallest - on spring holidays.

Thus, on the working days of the autumn period, the greatest environmental pollution of the ICE exhaust gas occurs, and on the spring days, the least.

On the working days of autumn, the largest amount of carbon is emitted by passenger cars, less - by medium trucks, and the smallest by buses. On a day off in spring, the largest amount of nitrogen oxides is emitted by a heavy cargo type of car, less by light trucks, medium trucks and cars, and the smallest by buses.

On autumn days off, the largest amount of carbon monoxide is formed by cars and light trucks, and the least by buses and heavy trucks. On a working day in spring, a large amount of carbon monoxide is emitted by a passenger car, the least by buses.

3.3 Agrochemical analysis of the studied soils

The results of the chemical analysis of soils selected on the roadside sections of the federal highway are presented in the table.

Agrochemical indicators

Distance from the road KCI Humus, %P 2ABOUT 5,mg/kg5 m 30 m 50 m 100 m 300 m5.4 5.1 4.9 5.4 5.22.1 2.5 2.7 2.6 2.4153 174 180 189 195

Agrochemical analysis showed that the soil of the studied area is slightly acidic, the studied areas did not differ from each other in acidity. According to the humus content, the soils are slightly humus.

It can be noted that the phosphorus content increases with distance from the road.

Thus, the characteristics of soils according to agrochemical indicators indicate that only soils located at a distance of 100 m and 300 m from the road are optimal for the growth and development of plants.

The analysis of soil samples for the content of heavy metals in them showed that (Table 7) if we take into account that the MPC of cadmium in the soil is 0.3 mg/kg (Staroverova, 2000), then in the soil located at a site of 5 m from the road , the content of cadmium exceeded this MPC by 1.3 times. With distance from the road, the content of cadmium in the soil decreases.

Distance from the roadCd, mg/kgZn, mg/kgPb, mg/kg5 m 30 m 50 m 100 m 300 m0.4 0.15 00.7 0.04 0.0153.3 2.4 2.0 1.8 1 .05.0 2.0 1.5 1.0 0.2PDK-236

The MPC index for zinc is 23 mg/kg (Staroverova, 2000), therefore, it can be said that roadside areas are not contaminated with zinc in this area. The highest zinc content in 5 m is 3.3 mg/kg from the road, the lowest in 300 m is 1.0 mg/kg.

On the basis of the above, we can conclude that road transport is a source of soil contamination of the studied roadside areas on the federal highway, only with cadmium. Moreover, a regularity is observed: with increasing distance from the road, the amount of heavy metals in the soil decreases, that is, part of the metals settles near the road.

3.4 Determination of phytotoxicity

Analyzing the data obtained in the study of the phytotoxicity of soil polluted with vehicle emissions (Fig. 3), we can say that the greatest phytotoxic effect was manifested at 50 and 100 m from the road (43 and 47%, respectively). This can be explained by the fact that the largest amount of pollutants settles 50 and 100 m from the road, due to the peculiarities of their distribution. This pattern was noted by a number of authors, for example, by N.A. Golubkina (2004).

Rice. Fig. 3. Influence of soil phytotoxicity on the length of seedlings of radish cv. Rosovo-red with a white tip

After testing this technique, it should be noted that we do not recommend using radish as a test culture.

A study of the data obtained when determining the radish germination energy showed that, in comparison with the control variant, in the variants with a distance of 50 and 100 m, the W was 1.4 and 1.3 times less, respectively.

The radish germination energy did not differ significantly from the control variant only at a distance of 300 m from the federal highway.

It should be noted that the same trend is observed in the analysis of data on the germination of the studied culture.

The highest germination was obtained in the control variant (97%), and the smallest - in the variant 50 m from the road (76%), which is 1.3 times less than in the control variant.

Dispersion analysis of the obtained data showed that the difference is observed only at 50 m and 30 m from the road, in other cases the difference is insignificant.

3.5 Lichen indication

The results of the study of the species composition and the state of lichens are presented in Table 11.

When studying lichens, two of their species were found in the studied areas: Platysmatia glauca and Platysmatia glauca.

Lichen coverage of the trunk varies from Hypohymnia swollen (Platysmatia glauca) ranged from 37.5 to 70 cm 3, Platysmatia glauca (Platysmatia glauca) from 20 to 56.5 cm3 .

The influence of the federal highway on the state of lichens

From the trial plot Species and number of the tree Name of the lichen species Place and record on the trunk Stem cover, cm 3Total coverage, % Total coverage score11 - birch Hypogymnia physodes (Hypogymnia physodes) Strip 702352 - birch-----3 - spruce-----4 - birch Platism gray (Platismatia Forest protection strip 55,59,235 - spruce Platism gray forest protection strip 35,55,9321 - spruce Forest protection strip 56,59,433 - birch Hypohymous swollen -0--4 - spruce Hypohymous swollen-0--5 - birchHypohymous swollen-0--31 - birch Platization gray-gray forest protection strip 37,56,242 - spruce Hypohymical swollen-0--3 - birch Hypohymical swollen forest protection strip 451544 - spruce Platization gray-gray co-construction Strip20,53,425 - spruceHypohymnaya swollen-0--41 - birchHypohymous swollen forest protection strip 421442 - birch Strip 12,52,0151 - spruce Strip 15533 - birch Hypohymous swollen-0--4 - birch Platization gray-gray Forest protection Strip 35,55,935 - spruce Hypohymous swollen-0--

The total coverage was: Hypohymnia swollen (Platysmatia glauca) from 2% to 23%, and Platysmatia glauca from 5% to 9%.

When using a ten-point scale (Table 12), we can conclude that there is pollution by vehicle emissions. The total coverage of Hypohymnia swollen (Platysmatia glauca) is from 1 to 5 points, and Platysmatia glauca is from 1 to 3 points.

4. Economic section

.1 Calculation of economic damage from emissions

The criteria for the ecological and economic efficiency of agricultural production is the maximization of the solution of the problem of meeting the public demand for agricultural products obtained with optimal production costs while preserving and reproducing the environment.

The determination of the environmental and economic efficiency of agricultural production is carried out on the basis of calculations of the indicator of environmental and economic damage.

Ecological and economic damage is the actual or possible losses, expressed in value, caused to agriculture as a result of the deterioration of the quality of the natural environment, with additional costs to compensate for these losses. The ecological and economic damage caused to the land used in agriculture as the main means of production is manifested in the cost of assessing the qualitative deterioration of its condition, which is expressed primarily in the reduction of soil fertility and loss of agricultural land productivity (Minakov, 2003).

The purpose of this section is to determine the damage from vehicle emissions on the federal highway "Kazan - Yekaterinburg" from agricultural use.

An allotment strip runs along the federal highway. The territory on which it is located belongs to SHPK "Rus". There is a shelterbelt next to the right of way, then there is a field. The company uses it in agricultural production.

It is known that plants growing in this area accumulate some components of GHG, and they, in turn, move along the links of the food chain (grass - farm animals - humans), thereby reducing the quality of feed, reducing yields, livestock productivity and the quality of livestock products. deterioration of animal and human health.

In order to make calculations, it is necessary to know the average hay yield per 1 hectare and the cost of 1 centner of hay for the last 3 years (2006-2007). The average yield of hay over the past 3 years was: 17.8 q/ha, the cost of 1 q of hay was 64.11.

Ecological - economic damage (E) from the withdrawal of the ROW from agricultural use is calculated by the formula:

where B is the gross collection of hay from the withdrawn area; C - the cost of 1 centner of hay, rub.

Gross hay harvest is calculated by the formula:

B = Ur * P

where R - average yield for 3 years, c/ha; P - withdrawn area, ha

B \u003d 17.8 * 22.5 \u003d 400 c

Y \u003d 400 * 64.11 \u003d 25676 rubles.

Let us assume that the farm will fulfill the deficiency by purchasing it at the market price. Then, the cost of its acquisition can be calculated by the formula:

Zpr = K*C,

where Z etc - the cost of purchasing hay at the market price, rubles; K - the required amount to buy hay, q; C - market price of 1 centner of hay.

Z value etc is equal to the unreceived hay due to land withdrawal, that is, 400 centners, the market price is 1 centner, the market price of 1 centner of hay is 200 rubles.

Then, Z pr \u003d 17.8 * 200 \u003d 80.100 rubles.

Thus, the land area was 17.8 hectares. The loss of hay in physical weight will be 400 centners. With the withdrawal of the right of way of the road from agricultural use, the annual loss amounted to 25,676 rubles. the cost of buying hay not received will be 80100.

conclusions

Based on the conducted research, the following conclusions can be drawn:

1. The composition of the exhaust gases of internal combustion engines includes 200 components, the most toxic to living organisms include carbon monoxide, nitrogen oxides, hydrocarbons, aldehydes, dioxides, sulfur dioxide and heavy metals.
2. Exhaust gases affect crops, which are the main component of the agroecosystem. The impact of exhaust gases leads to a decrease in yield and quality of agricultural products. Some substances from emissions can accumulate in plants, which creates an additional hazard to human and animal health.
3. In autumn, 4,080 vehicles pass through a 12-hour working day, which emitted about 3.3 tons of harmful substances into the environment per 1 km of the road, and 1.2 tons of harmful substances in the spring. In autumn, during a 12-hour day off, 2880 vehicles were observed, which formed 3.2 tons of harmful substances, and in the spring - 1680 tons, which formed 1.7 tons of harmful substances. The greatest pollution occurs due to cars and light trucks.
4. An agrochemical analysis of the soil showed that the study area in this area is slightly acidic, in the experimental variants it ranged from 4.9 to 5.4 pH KCI, the soils have a low humus content and are slightly contaminated with cadmium.
5. The economic damage from vehicle emissions on the federal highway "Kazan - Yekaterinburg" is 25,676 rubles.

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Interaction of transport objects with the environment

Transport is one of the main sources of air pollution in the atmosphere. Environmental problems associated with the impact of various transport facilities on the environment are determined by the amount of emissions of toxicants by engines, and also consist in the pollution of water bodies. Solid waste generation and noise pollution contribute their share of negative impacts. At the same time, it is road transport that ranks first as an environmental pollutant and consumer of energy resources. An order of magnitude lower is the negative effect of railway transport facilities. Pollution - in decreasing order - from air, sea and inland water transport is even less.

Impact of road transport on the environment

By burning a huge amount of petroleum products, cars harm both the environment (primarily the atmosphere) and human health. The air is depleted of oxygen, saturated with harmful substances of exhaust gases, the amount of dust suspended in the atmosphere and settled on the surface of various substrates increases.

Wastewater from the enterprises of the motor transport complex is usually saturated with oil products and suspended solids, and surface runoff from the roadway contains additional heavy metals (lead, cadmium, etc.) and chlorides.

Cars are also intensive factors in the elimination of vertebrates and invertebrates, they are also dangerous for humans, causing many deaths and severe injuries.

Remark 1

Owners of personal vehicles often wash their cars on the banks of water bodies using synthetic detergents that enter the water.

Damage to natural ecosystems is caused by the chemical method of eliminating snow and ice from road surfaces with the help of reagents - chloride compounds (through direct contact and through the soil).

The dangerous effect of these salts is manifested in the process of corrosion of the metal that is part of the car, the destruction of road machines and structural elements of road signs and roadside barriers.

Example 1

The share of cars operated, despite the excess of modern standards for toxicity and opacity of emissions, averages 20 - 25%.

The local geo-ecological impact of transport is manifested in the intensive accumulation of carbon monoxide, nitrogen oxides, hydrocarbons or lead in the vicinity of pollution sources (along highways, main streets, in tunnels, at intersections). Part of the pollutants is transported from the place of emission, causing regional geoecological impacts. Carbon dioxide and other gases that have a greenhouse effect, spreading throughout the atmosphere, causing global geoecological impacts that are unfavorable for humans.

Example 2

Approximately 15% of the samples in the areas affected by transport exceeded the MPCs of heavy metals hazardous to health.

The main motor transport wastes are batteries (lead), interior upholstery elements (plastic), car tires, fragments of car bodies (steel).

Influence of rail transport

The main source of air pollution is exhaust gases emitted by diesel locomotives containing carbon monoxide, nitrogen oxides, various types of hydrocarbons, sulfur dioxide, and soot.

In addition, up to 200 m³ of wastewater containing pathogenic microorganisms per year from passenger cars per kilometer of track, in addition, up to 12 tons of dry garbage are thrown out.

In the process of washing the rolling stock, detergents are thrown into the water along with wastewater - synthetic surfactants, various petroleum products, phenols, hexavalent chromium, acids, alkalis, various organics and inorganic suspended solids.

Noise pollution from moving trains causes negative health effects and generally affects the quality of life of the population.

Impact of air transport

Air transport saturates the atmosphere with carbon monoxide, hydrocarbons, nitrogen oxides, soot, and aldehydes. The engines of aviation and rocket transport objects have a negative effect on the troposphere, stratosphere, and outer space. Emissions that contribute to the destruction of the planet's ozone layer account for about 5% of toxic substances entering the atmosphere from the entire transport sector.

Fleet impact

The river and, in particular, the marine fleet seriously pollutes the atmosphere and hydrosphere. Transport shipping saturates the atmosphere with freons, which destroy the ozone layer of the Earth's atmosphere, and the fuel emits oxides of sulfur, nitrogen, and carbon monoxide during combustion. It is known that 40% of the negative impacts of water transport are due to air pollution. 60% “share” among themselves noise pollution, vibrations unusual for the biosphere, solid waste and corrosion processes of transport facilities, oil spills during tanker accidents and some other things. Mortality of juvenile fish and many other hydrobionts is associated with waves occurring during the operation of sea vessels.

Road transport is the most aggressive in comparison with other modes of transport in relation to the environment. It is a powerful source of its chemical (supplies a huge amount of toxic substances into the environment), noise and mechanical pollution. It should be emphasized that with the increase in the car park, the level of the harmful impact of vehicles on the environment increases intensively. So, if in the early 70s, hygienists determined the share of pollution introduced into the atmosphere by road transport, on average, equal to 13%, now it has already reached 50% and continues to grow. And for cities and industrial centers, the share of vehicles in the total volume of pollution is much higher and reaches 70% or more, which creates a serious environmental problem that accompanies urbanization.

There are several sources of toxic substances in cars, the main ones are three:

• exhaust gases
• crankcase gases
• fuel vapors

Rice. Sources of toxic emissions

The largest share of chemical pollution of the environment by road transport is accounted for by the exhaust gases of internal combustion engines.

Theoretically, it is assumed that with the complete combustion of fuel, as a result of the interaction of carbon and hydrogen (which are part of the fuel) with atmospheric oxygen, carbon dioxide and water vapor are formed. In this case, the oxidation reactions have the form:

С+О2=СО2,
2H2+O2=2H2.

In practice, due to the physical and mechanical processes in the engine cylinders, the actual composition of the exhaust gases is very complex and includes more than 200 components, a significant part of which are toxic.

Table. Approximate composition of exhaust gases of automobile engines

The composition of the exhaust gases of engines using the example of passenger cars without their neutralization can be represented in the form of a diagram.

Rice. Components of exhaust gases without the use of neutralization

As can be seen from the table and figure, the composition of the exhaust gases of the considered types of engines differs significantly, primarily in the concentration of products of incomplete combustion - carbon monoxide, hydrocarbons, nitrogen oxides and soot.

Toxic components of exhaust gases include:

• carbon monoxide
• hydrocarbons
• nitrogen oxides
• sulfur oxides
• aldehydes
• benzo(a)pyrene
• lead compounds

The difference in the composition of the exhaust gases of gasoline and diesel engines is explained by the large excess air coefficient α (the ratio of the actual amount of air entering the engine cylinders to the amount of air theoretically required for combustion of 1 kg of fuel) for diesel engines and better fuel atomization (fuel injection). In addition, in a gasoline carburetor engine, the mixture for different cylinders is not the same: for cylinders located closer to the carburetor, it is rich, and for those farther from it, it is poorer, which is a disadvantage of gasoline carburetor engines. Part of the air-fuel mixture in carburetor engines enters the cylinders not in a vapor state, but in the form of a film, which also increases the content of toxic substances due to poor combustion of the fuel. This disadvantage is not typical for gasoline engines with fuel injection, since the fuel is supplied directly to the intake valves.

The reason for the formation of carbon monoxide and partially hydrocarbons is the incomplete combustion of carbon (the mass fraction of which in gasoline reaches 85%) due to an insufficient amount of oxygen. Therefore, the concentrations of carbon monoxide and hydrocarbons in the exhaust gases increase with the enrichment of the mixture (α 1, the probability of these transformations in the flame front is small and the exhaust gases contain less CO, but there are additional sources of its occurrence in the cylinders:

• low-temperature sections of the flame of the fuel ignition stage
• fuel droplets entering the chamber at the late stages of injection and burning in a diffusion flame with a lack of oxygen
• soot particles formed during the propagation of a turbulent flame along a heterogeneous charge, in which, with a general excess of oxygen, zones with its deficiency can be created and reactions of the type can be carried out:

2С+О2 → 2СО.

Carbon dioxide CO2 is a non-toxic, but harmful substance due to the recorded increase in its concentration in the planet's atmosphere and its impact on climate change. The main share of CO formed in the combustion chamber is oxidized to CO2 without leaving the chamber, because the measured volume fraction of carbon dioxide in the exhaust gases is 10-15%, i.e. 300 ... 450 times more than in atmospheric air. The irreversible reaction makes the greatest contribution to the formation of CO2:

CO + OH → CO2 + H

Oxidation of CO to CO2 occurs in the exhaust pipe, as well as in the exhaust gas converters that are installed on modern cars for the forced oxidation of CO and unburned hydrocarbons to CO2 due to the need to comply with toxicity standards.

hydrocarbons

Hydrocarbons - numerous compounds of various types (for example, C6H6 or C8H18) consist of the original or decayed fuel molecules, and their content increases not only with enrichment, but also with depletion of the mixture (a > 1.15), which is explained by an increased amount of unreacted (unburned) ) fuel due to excess air and misfires in individual cylinders. The formation of hydrocarbons also occurs due to the fact that at the walls of the combustion chamber the temperature of the gases is not high enough to burn the fuel, so the flame is extinguished here and complete combustion does not occur. The most toxic polycyclic aromatic hydrocarbons.

In diesel engines, light gaseous hydrocarbons are formed during the thermal decomposition of fuel in the flame failure zone, in the core and in the leading front of the flame, on the wall on the walls of the combustion chamber and as a result of secondary injection (post-injection).

Solid particles include insoluble (solid carbon, metal oxides, silicon dioxide, sulfates, nitrates, asphalts, lead compounds) and soluble in organic solvent (resins, phenols, aldehydes, varnish, soot, heavy fractions contained in fuel and oil) substances.

Solid particles in the exhaust gases of supercharged diesel engines consist of 68 ... 75% of insoluble substances, 25 ... 32% of soluble substances.

Soot

Soot (solid carbon) is the main component of insoluble particulate matter. It is formed during bulk pyrolysis (thermal decomposition of hydrocarbons in the gas or vapor phase with a lack of oxygen). The mechanism of soot formation includes several stages:

• nucleation
• growth of nuclei to primary particles (hexagonal plates of graphite)
• increase in particle size (coagulation) to complex formations - conglomerates, including 100 ... 150 carbon atoms
• burnout

The release of soot from the flame occurs at α = 0.33…0.70. In tuned engines with external carburetion and spark ignition (petrol, gas), the likelihood of such zones is negligible. In diesel engines, local over-fueled zones are formed more often and the listed soot formation processes are fully realized. Therefore, soot emissions from the exhaust gases of diesel engines are greater than those of spark ignition engines. The formation of soot depends on the properties of the fuel: the greater the C/H ratio in the fuel, the higher the soot yield.

The composition of solid particles, in addition to soot, includes compounds of sulfur and lead. Nitrogen oxides NOx represent a set of the following compounds: N2O, NO, N2O3, NO2, N2O4 and N2O5. In the exhaust gases of automobile engines, NO prevails (99% in gasoline engines and more than 90% in diesel engines). In the combustion chamber, NO can form:

• at high-temperature air nitrogen oxidation (thermal NO)
• as a result of low-temperature oxidation of nitrogen-containing fuel compounds (fuel NO)
• due to the collision of hydrocarbon radicals with nitrogen molecules in the combustion reaction zone in the presence of temperature pulsation (fast NO)

The combustion chambers are dominated by thermal NO formed from molecular nitrogen during the combustion of a lean air-fuel mixture and a mixture close to stoichiometric behind the flame front in the zone of combustion products. Predominantly during the combustion of lean and moderately rich mixtures (α > 0.8), reactions occur according to a chain mechanism:

O + N2 → NO + N
N + O2 → NO + O
N+OH → NO+H.

In rich mixtures< 0,8) осуществляются также реакции:

N2 + OH → NO + NH
NH + O → NO + OH.

In lean mixtures, the NO output is determined by the maximum temperature of the chain-thermal explosion (maximum temperature 2800 ... 2900 ° K), i.e., the kinetics of formation. In rich mixtures, the NO yield ceases to depend on the maximum explosion temperature and is determined by the decomposition kinetics, and the NO content decreases. During the combustion of lean mixtures, the formation of NO is significantly affected by the uneven temperature field in the zone of combustion products and the presence of water vapor, which is an inhibitor in the NOx oxidation chain reaction.

The high intensity of the process of heating and then cooling the mixture of gases in the ICE cylinder leads to the formation of significantly nonequilibrium concentrations of the reactants. There is a freezing (hardening) of the formed NO at the level of maximum concentration, which is found in the exhaust gases due to a sharp slowdown in the rate of decomposition of NO.

The main lead compounds in vehicle exhaust gases are chlorides and bromides, as well as (in smaller amounts) oxides, sulfates, fluorides, phosphates and some of their intermediate compounds, which are in the form of aerosols or solid particles at temperatures below 370 ° C. About 50% of lead remains in the form of soot on engine parts and in the exhaust pipe, the rest goes into the atmosphere with exhaust gases.

A large number of lead compounds are released into the air when this metal is used as an antiknock agent. Currently, lead compounds are not used as antiknock agents.

Sulfur oxides

Sulfur oxides are formed during the combustion of sulfur contained in the fuel by a mechanism similar to the formation of CO.

The concentration of toxic components in exhaust gases is estimated in volume percent, ppm by volume - ppm -1, (parts per million, 10,000 ppm \u003d 1% by volume) and less often in milligrams per 1 liter of exhaust gases.

In addition to exhaust gases, crankcase gases (in the absence of closed crankcase ventilation, as well as evaporation of fuel from the fuel system) are sources of environmental pollution by cars with carburetor engines.

The pressure in the crankcase of a gasoline engine, with the exception of the intake stroke, is much less than in the cylinders, so part of the air-fuel mixture and exhaust gases break through leaks in the cylinder-piston group from the combustion chamber into the crankcase. Here they mix with oil and fuel vapors washed off the cylinder walls of a cold engine. Crankcase gases dilute the oil, contribute to water condensation, aging and contamination of the oil, and increase its acidity.

In a diesel engine, during the compression stroke, clean air breaks into the crankcase, and during combustion and expansion, exhaust gases with concentrations of toxic substances proportional to their concentrations in the cylinder. In diesel crankcase gases, the main toxic components are nitrogen oxides (45 ... 80%) and aldehydes (up to 30%). The maximum toxicity of crankcase gases of diesel engines is 10 times lower than that of exhaust gases, therefore the proportion of crankcase gases in a diesel engine does not exceed 0.2 ... 0.3% of the total emission of toxic substances. Given this, forced crankcase ventilation is usually not used in automotive diesel engines.

The main sources of fuel vapors are the fuel tank and the power system. Higher engine compartment temperatures, due to more loaded engine operating conditions and the relative crampedness of the vehicle's engine compartment, cause significant fuel evaporation from the fuel system when a hot engine is stopped. Given the large emission of hydrocarbon compounds as a result of fuel evaporation, all car manufacturers are currently using special systems for their capture.

In addition to hydrocarbons coming from the car fuel system, significant atmospheric pollution with volatile hydrocarbons of car fuel occurs when cars are refueled (on average, 1.4 g of CH per 1 liter of filled fuel). Evaporation also causes physical changes in the gasolines themselves: due to a change in the fractional composition, their density increases, starting qualities deteriorate, and the octane number of thermal cracking and direct distillation gasolines decreases. In diesel vehicles, fuel evaporation is practically absent due to the low volatility of diesel fuel and the tightness of the diesel fuel system.

The level of air pollution is assessed by comparing the measured and the maximum allowable concentration (MAC). MPC values ​​are set for various toxic substances with constant, average daily and one-time actions. The table shows the average daily MPC values ​​for some toxic substances.

Table. Permissible concentrations of toxic substances

According to research, a passenger car with an average annual mileage of 15 thousand km "inhales" 4.35 tons of oxygen and "exhales" 3.25 tons of carbon dioxide, 0.8 tons of carbon monoxide, 0.2 tons of hydrocarbons, 0.04 tons of oxides nitrogen. Unlike industrial enterprises, the emission of which is concentrated in a certain area, a car disperses the products of incomplete combustion of fuel throughout almost the entire territory of cities, and directly in the surface layer of the atmosphere.

The share of pollution by cars in large cities reaches large values.

Table. The share of road transport in the total air pollution in the largest cities of the world, %

Toxic components of exhaust gases and fumes from the fuel system adversely affect the human body. The degree of exposure depends on their concentrations in the atmosphere, the state of the person and his individual characteristics.

carbon monoxide

Carbon monoxide (CO) is a colorless, odorless gas. The density of CO is less than air, and therefore it can easily spread in the atmosphere. Entering the human body with inhaled air, CO reduces the function of oxygen supply, displacing oxygen from the blood. This is due to the fact that the absorption of CO by the blood is 240 times higher than the absorption of oxygen. CO has a direct effect on tissue biochemical processes, resulting in a violation of fat and carbohydrate metabolism, vitamin balance, etc. As a result of oxygen starvation, the toxic effect of CO is associated with a direct effect on the cells of the central nervous system. An increase in the concentration of carbon monoxide is also dangerous because, as a result of oxygen starvation of the body, attention is weakened, the reaction slows down, the efficiency of drivers decreases, which affects road safety.

The nature of the toxic effects of CO can be traced from the diagram shown in the figure.

Rice. Diagram of the effects of CO on the human body:
1 - death; 2 - mortal danger; 3 - headache, nausea; 4 - the beginning of the toxic effect; 5 - the beginning of a noticeable action; 6 - imperceptible action; T, h - exposure time

It follows from the diagram that even with a low concentration of CO in the air (up to 0.01%), prolonged exposure to it causes a headache and leads to a decrease in performance. A higher concentration of CO (0.02...0.033%) leads to the development of atherosclerosis, the occurrence of myocardial infarction and the development of chronic lung diseases. Moreover, the effect of CO on people suffering from coronary insufficiency is especially harmful. At a CO concentration of about 1%, loss of consciousness occurs after a few breaths. CO also has a negative effect on the human nervous system, causing fainting, as well as changes in the color and light sensitivity of the eyes. Symptoms of CO poisoning are headache, palpitations, shortness of breath and nausea. It should be noted that at relatively low concentrations in the atmosphere (up to 0.002%), CO associated with hemoglobin is gradually released and human blood is cleared of it by 50% every 3-4 hours.

Hydrocarbon compounds

Hydrocarbon compounds have not yet been sufficiently studied in terms of their biological action. However, experimental studies have shown that polycyclic aromatic compounds have caused cancer in animals. Under certain atmospheric conditions (calm, intense solar radiation, significant temperature inversion), hydrocarbons serve as the initial products for the formation of extremely toxic products - photooxidants, which have a strong irritating and general toxic effect on human organs, and form photochemical smog. Carcinogenic substances are especially dangerous from the group of hydrocarbons. The most studied is the polynuclear aromatic hydrocarbon benzo(a)pyrene, also known as 3,4 benzo(a)pyrene, a substance that is a yellow crystal. It has been established that malignant tumors appear in places of direct contact of carcinogenic substances with tissue. If carcinogenic substances deposited on dust-like particles enter the lungs through the respiratory tract, they are retained in the body. Toxic hydrocarbons are also gasoline vapors that enter the atmosphere from the fuel system, and crankcase gases escaping through ventilation devices and leaks in the connections of individual engine components and systems.

Nitric oxide

Nitric oxide is a colorless gas, and nitrogen dioxide is a red-brown gas with a characteristic odor. Nitrogen oxides, when ingested, combine with water. At the same time, they form compounds of nitric and nitrous acids in the respiratory tract, irritating the mucous membranes of the eyes, nose and mouth. Nitrogen oxides are involved in the processes leading to the formation of smog. The danger of their impact lies in the fact that the poisoning of the body does not appear immediately, but gradually, and there are no neutralizing agents.

Soot

Soot, when it enters the human body, causes negative consequences in the respiratory organs. If relatively large soot particles of 2…10 microns in size are easily excreted from the body, then small ones of 0.5…2 microns in size linger in the lungs, respiratory tract, and cause allergies. Like any aerosol, soot pollutes the air, impairs visibility on the roads, but, most importantly, heavy aromatic hydrocarbons, including benzo(a)pyrene, are adsorbed on it.

Sulfur dioxide SO2

Sulfur dioxide SO2 is a colorless gas with a pungent odor. The irritant effect on the upper respiratory tract is due to the absorption of SO2 by the moist surface of the mucous membranes and the formation of acids in them. It disrupts protein metabolism and enzymatic processes, causes eye irritation, cough.

CO2 carbon dioxide

Carbon dioxide CO2 (carbon dioxide) - does not have a toxic effect on the human body. It is well absorbed by plants with the release of oxygen. But if there is a significant amount of carbon dioxide in the earth's atmosphere that absorbs the sun's rays, a greenhouse effect is created, leading to the so-called "thermal pollution". As a result of this phenomenon, the air temperature in the lower layers of the atmosphere rises, warming occurs, and various climatic anomalies are observed. In addition, an increase in the content of CO2 in the atmosphere contributes to the formation of "ozone" holes. With a decrease in the concentration of ozone in the earth's atmosphere, the negative impact of hard ultraviolet radiation on the human body increases.

The car is also a source of air pollution with dust. During driving, especially when braking, as a result of the friction of tires on the road surface, rubber dust is formed, which is constantly present in the air on highways with heavy traffic. But tires are not the only source of dust. Solid particles in the form of dust are emitted with exhaust gases, are brought into the city in the form of dirt on car bodies, are formed from abrasion of the road surface, are lifted into the air by vortex flows that occur when the car is moving, etc. Dust adversely affects human health, has a detrimental effect on the plant world.

In urban conditions, the car is a source of warming the surrounding air. If 100,000 cars move simultaneously in a city, this is equal to the effect produced by 1 million liters of hot water. Exhaust gases from vehicles containing warm water vapor contribute to climate change in the city. Higher steam temperatures increase heat transfer by the moving medium (thermal convection), resulting in more precipitation over the city. The influence of the city on the amount of precipitation is especially clearly seen in their regular increase, which occurs in parallel with the growth of the city. For a ten-year observation period, in Moscow, for example, 668 mm of precipitation fell per year, in its vicinity - 572 mm, in Chicago - 841 and 500 mm, respectively.

Among the side effects of human activity are acid rain - products of combustion dissolved in atmospheric moisture - oxides of nitrogen and sulfur. This mainly applies to industrial enterprises, the emissions of which are diverted high above the surface level and which contain a lot of sulfur oxides. The harmful effect of acid rain is manifested in the destruction of vegetation and the acceleration of corrosion of metal structures. An important factor here is the fact that acid rains, together with the movement of atmospheric air masses, can overcome distances of hundreds and thousands of kilometers, crossing the borders of states. In the periodical press, there are reports of acid rain falling in different countries of Europe, in the USA, Canada and seen even in such protected areas as the Amazon basin.

Temperature inversions, a special state of the atmosphere, in which the air temperature increases with height, rather than decreases, have an adverse effect on the environment. Surface temperature inversions are the result of intense heat radiation from the soil surface, as a result of which both the surface and the adjacent air layers are cooled. This state of the atmosphere prevents the development of vertical air movements, so water vapor, dust, gaseous substances accumulate in the lower layers, contributing to the formation of layers of haze and fog, including smog.

The widespread use of salt to combat icing on roads leads to a reduction in the life of cars, causes unexpected changes in roadside flora. So, in England, the appearance along the roads of plants characteristic of sea coasts was noted.

The car is a strong polluter of water bodies, underground water sources. It has been determined that 1 liter of oil can make several thousand liters of water unfit for drinking.

A large contribution to environmental pollution is made by the maintenance and repair of rolling stock, which require energy costs and are associated with high water consumption, the emission of pollutants into the atmosphere, and the generation of waste, including toxic ones.

When performing maintenance of vehicles, divisions, zones of periodic and operational forms of maintenance are involved. Repair work is carried out at production sites. Technological equipment, machine tools, mechanization and boiler plants used in maintenance and repair processes are stationary sources of pollutants.

Table. Sources of release and composition of harmful substances in production processes at operational and repair enterprises of transport

Wastewater

During the operation of vehicles, sewage is generated. The composition and quantity of these waters are different. Waste water is returned back to the environment, mainly to the objects of the hydrosphere (river, canal, lake, reservoir) and land (fields, reservoirs, underground horizons, etc.). Depending on the type of production, wastewater at transport enterprises can be:

• wastewater from car washes
• oily effluents from production sites (washing solutions)
• wastewater containing heavy metals, acids, alkalis
• wastewater containing paint, solvents

Waste water from car washing is from 80 to 85% of the volume of industrial effluents of motor transport organizations. The main pollutants are suspended solids and oil products. Their content depends on the type of car, the nature of the road surface, weather conditions, the nature of the cargo being transported, etc.

Wastewater from washing units, assemblies and parts (waste cleaning solutions) is distinguished by the presence of a significant amount of oil products, suspended solids, alkaline components and surfactants.

Wastewater containing heavy metals (chromium, copper, nickel, zinc), acids and alkalis are most typical for auto repair industries using galvanic processes. They are formed during the preparation of electrolytes, surface preparation (electrochemical degreasing, etching), electroplating and washing of parts.

In the process of painting work (by pneumatic spraying), 40% of paint and varnish materials enter the air of the working area. When carrying out these operations in spray booths equipped with hydraulic filters, 90% of this amount settles on the elements of the hydraulic filters themselves, 10% is carried away with water. Thus, up to 4% of the used paint and varnish materials get into the wastewater of the painting areas.

The main direction in the field of reducing pollution of water bodies, groundwater and groundwater by industrial waste is the creation of systems for recycling water supply to production.

Repair work is also accompanied by soil pollution, accumulation of metal, plastic and rubber waste near production sites and departments.

During the construction and repair of communication lines, as well as production and household facilities of transport enterprises, water, soil, fertile soils, and mineral resources are withdrawn from ecosystems, natural landscapes are destroyed, and flora and fauna are interfered with.

Noise

Along with other modes of transport, industrial equipment, household appliances, a car is a source of artificial noise background of the city, which, as a rule, negatively affects a person. It should be noted that even without noise, if it does not exceed the permissible limits, a person feels discomfort. It is no coincidence that Arctic researchers have repeatedly written about “white silence”, which has a depressing effect on a person, while the “noise design” of nature has a positive effect on the psyche. However, artificial noise, especially loud noise, has a negative effect on the nervous system. The population of modern cities faces a serious problem of noise control, since strong noise not only leads to hearing loss, but also causes mental disorders. The danger of noise exposure is exacerbated by the property of the human body to accumulate acoustic irritation. Under the influence of noise of a certain intensity, changes occur in blood circulation, the work of the heart and endocrine glands, and muscle endurance decreases. Statistics show that the percentage of neuropsychiatric diseases is higher among people working in environments with high noise levels. The reaction to noise is often expressed in increased excitability and irritability, covering the entire sphere of sensitive perceptions. People who are constantly exposed to noise often become difficult to communicate with.

Noise has a harmful effect on the visual and vestibular analyzers, reduces the stability of clear vision and reflex activity. The sensitivity of twilight vision weakens, the sensitivity of daytime vision to orange-red rays decreases. In this sense, noise is an indirect killer of many people on the world's highways. This applies both to drivers of vehicles working in conditions of intense noise and vibration, and to residents of large cities with high noise levels.

Noise in combination with vibration is especially harmful. If a short-term vibration tones the body, then a constant one causes the so-called vibration disease, i.e. a whole range of disorders in the body. The driver's visual acuity is reduced, the field of view narrows, color perception or the ability to judge the distance to an oncoming vehicle may change. These violations, of course, are individual, but for a professional driver they are always undesirable.

Infrasound is also dangerous, i.e. sound with a frequency of less than 17 Hz. This individual and inaudible enemy causes reactions that are contraindicated for a person behind the wheel. The impact of infrasound on the body causes drowsiness, deterioration of visual acuity and a slow reaction to danger.

Of the sources of noise and vibration in a car (gearbox, rear axle, cardan shaft, body, cab, suspension, as well as wheels, tires), the main one is the engine with its intake and exhaust, cooling and power systems.

Rice. Truck noise source analysis:
1 – total noise; 2 - engine; 3 – system of release of the fulfilled gases; 4 - fan; 5 - air inlet; 6 - the rest

However, at vehicle speeds over 50 km/h, tire noise is predominant and increases in proportion to vehicle speed.

Rice. The dependence of the noise of the car on the speed of movement:
1 - range of noise dispersion due to different combinations of road surfaces and tires

The cumulative effect of all sources of acoustic radiation leads to those high noise levels that characterize a modern car. These levels also depend on other reasons:

• pavement condition
• speed and change of direction
• engine speed changes
• loads
• etc.

There are horse-drawn, automobile, agricultural (tractors and combines), railway, water, air and pipeline transport. The length of the world's main roads with hard surface exceeds 12 million km, air lines - 5.6 million km, railways - 1.5 million km, main pipelines - about 1.1 million km, inland waterways - more than 600 thousand km. Sea lines are many millions of kilometers.

All vehicles with autonomous prime movers pollute the atmosphere to some extent with chemical compounds contained in exhaust gases. On average, the contribution of certain types of vehicles to air pollution is as follows:

automobile - 85%;

sea ​​and river - 5.3%;

air - 3.7%;

railway - 3.5%;

agricultural - 2.5%.

In many large cities, such as Berlin, Mexico City, Tokyo, Moscow, St. Petersburg, Kiev, air pollution from automobile exhausts, according to various estimates, is from 80 to 95% of all pollution.

As for air pollution by other modes of transport, the problem is less acute here, since vehicles of these types are not concentrated directly in cities. So, in the largest railway junctions, all traffic has been switched to electric traction, and diesel locomotives are used only for shunting work. River and sea ports, as a rule, are located outside the residential areas of cities, and the movement of ships in the port areas is almost negligible. Airports, as a rule, are 20-40 km away from cities. In addition, large open spaces over airfields, as well as over river and sea ports, do not pose a danger of high concentrations of toxic impurities emitted by engines. Along with environmental pollution by harmful emissions, one should note the physical impact on the atmosphere in the form of the formation of anthropogenic physical fields (increased noise, infrasound, electromagnetic radiation). Of these factors, increased noise has the most massive impact. Transport is the main source of acoustic pollution of the environment. In large cities, the noise level reaches 70-75 dBA, which is several times higher than the permissible norms.

10.2. Automobile transport

The total global fleet of vehicles is more than 800 million units, of which 83-85% are cars, and 15-17% are trucks and buses. If the growth trends in the production of motor vehicles remain unchanged, then by 2015 the number of vehicles may increase to 1.5 billion units. Motor transport, on the one hand, consumes oxygen from the atmosphere, and on the other hand, it emits exhaust gases, crankcase gases and hydrocarbons into it due to their evaporation from fuel tanks and leakage of fuel supply systems. The car negatively affects almost all components of the biosphere: the atmosphere, water resources, land resources, the lithosphere and humans. An assessment of the environmental hazard through the resource and energy variables of the entire life cycle of a car from the moment of extraction of the mineral resources needed for its production to the recycling of waste after the end of its service showed that the environmental "cost" of a 1-ton car, in which approximately 2/3 of the mass is metal, equal to 15 to 18 tons of solid and 7 to 8 tons of liquid waste placed in the environment.

Emissions from motor vehicles are distributed directly to the streets of the city along the roads, having a direct harmful effect on pedestrians, residents of nearby houses and vegetation. It was revealed that zones with exceeding the MPC for nitrogen dioxide and carbon monoxide cover up to 90% of the urban area.

The car is the most active consumer of air oxygen. If a person consumes up to 20 kg of air (15.5 m 3) per day and up to 7.5 tons per year, then a modern car consumes about 12 m 3 of air or about 250 liters of oxygen in oxygen equivalent to burn 1 kg of gasoline. Thus, all road transport in the United States consumes 2 times more oxygen than nature regenerates it throughout their territory.

Thus, in large metropolitan areas, road transport absorbs ten times more oxygen than their entire population. Studies conducted on the highways of Moscow have shown that in calm calm weather and low atmospheric pressure on busy highways, the combustion of oxygen in the air often rises to 15% of its total volume.

It is known that at an oxygen concentration in the air below 17%, people develop symptoms of malaise, at 12% or less there is a danger to life, at a concentration below 11%, loss of consciousness occurs, and at 6%, breathing stops. On the other hand, there is not only little oxygen on these highways, but the air is still saturated with harmful substances from automobile exhaust. A feature of automobile emissions is also that they pollute the air at the height of human growth, and people breathe these emissions.

Composed of vehicle emissions includes about 200 chemical compounds, which, depending on the characteristics of the impact on the human body, are divided into 7 groups.

IN 1st group includes chemical compounds contained in the natural composition of atmospheric air: water (in the form of steam), hydrogen, nitrogen, oxygen and carbon dioxide. Motor transport emits such a huge amount of steam into the atmosphere that in Europe and the European part of Russia it exceeds the evaporation mass of all reservoirs and rivers. Because of this, cloudiness is growing, and the number of sunny days is noticeably reduced. Gray, without sun, days, unheated soil, constantly high humidity - all this contributes to the growth of viral diseases, a decrease in crop yields.

In 2nd group included carbon monoxide (maximum concentration limit 20 mg/m3; class 4). It is a colorless gas, odorless and tasteless, very slightly soluble in water. Inhaled by a person, it combines with blood hemoglobin and inhibits its ability to supply oxygen to body tissues. As a result, oxygen starvation of the body occurs and disturbances occur in the activity of the central nervous system. The effects of exposure depend on the concentration of carbon monoxide in the air; so, at a concentration of 0.05%, after 1 hour, signs of mild poisoning appear, and at 1%, loss of consciousness occurs after several breaths.

IN 3rd group includes nitric oxide (MPC 5 mg / m 3, 3 cells) - a colorless gas and nitrogen dioxide (MPC 2 mg / m 3, 3 cells) - a reddish-brown gas with a characteristic odor. These gases are impurities that contribute to the formation of smog. Getting into the human body, they, interacting with moisture, form nitrous and nitric acids (MPC 2 mg / m 3, 3 cells). The consequences of exposure depend on their concentration in the air, so, at a concentration of 0.0013%, there is a slight irritation of the mucous membranes of the eyes and nose, at 0.002% - the formation of methemoglobin, at 0.008% - pulmonary edema.

IN 4th group includes hydrocarbons. The most dangerous of them is 3,4-benz (a) pyrene (MPC 0.00015 mg / m 3, 1 class) - a powerful carcinogen. Under normal conditions, this compound is a needle-shaped yellow crystals, poorly soluble in water and well - in organic solvents. In human serum, the solubility of benzo(a)pyrene reaches 50 mg/ml.

IN 5th group includes aldehydes. The most dangerous for humans are acrolein and formaldehyde. Acrolein is an aldehyde of acrylic acid (MPC 0.2 mg / m 3, 2 cells), colorless, with the smell of burnt fat and a very volatile liquid that dissolves well in water. A concentration of 0.00016% is the threshold of odor perception, at 0.002% the smell is difficult to tolerate, at 0.005% it is unbearable, and at 0.014 death occurs after 10 minutes. Formaldehyde (MPC 0.5 mg / m 3, 2 cells) is a colorless gas with a pungent odor, easily soluble in water.

At a concentration of 0.007%, it causes slight irritation of the mucous membranes of the eyes and nose, as well as the upper respiratory organs, at a concentration of 0.018%, the breathing process is complicated.

IN 6th group includes soot (MPC 4 mg / m 3, 3 cells), which has an irritating effect on the respiratory system. Studies conducted in the United States have revealed that 50-60 thousand people die every year from soot pollution in the air. It was found that soot particles actively adsorb benzo(a)pyrene on its surface, as a result of which the health of children suffering from respiratory diseases, people with asthma, bronchitis, pneumonia, as well as the elderly deteriorates sharply.

IN 7th group includes lead and its compounds. Tetraethyl lead (MAC 0.005 mg/m 3 , 1 cell) is introduced into gasoline as an anti-knock additive. Therefore, about 80% of lead and its compounds that pollute the air enter it when using leaded gasoline. Lead and its compounds reduce the activity of enzymes and disrupt the metabolism in the human body, and also have a cumulative effect, i.e. ability to accumulate in the body. Lead compounds are especially harmful to the intellectual abilities of children. Up to 40% of the compounds that have got into it remain in the child's body. In the United States, the use of leaded gasoline is prohibited everywhere, and in Russia - in Moscow, St. Petersburg and a number of other large cities.

TOPIC: Impact of road transport on the environment

PLAN:

1.3.2 Consequences of TDC influence on biota of ecosystems

2. Problems of urban transport

2.1. The impact of vehicles on the urban environment

2.2. World level of motorization

2.3. Ways of greening urban transport

2.4. Municipal experience in personal vehicle mileage management

2.5. The role of public transport

2.6. The problem of recycling old cars

3.1. Aviation and rocket carriers

The transport complex, in particular in Russia, which includes automobile, sea, inland waterway, rail and air transport, is one of the largest pollutants of the atmospheric air; its impact on the environment is expressed mainly in the emissions of toxicants into the atmosphere with exhaust gases engines and harmful substances from stationary sources, as well as pollution of surface water bodies, the formation of solid waste and the impact of traffic noise.

The main sources of environmental pollution and consumers of energy resources include road transport and the infrastructure of the motor transport complex.

Air pollutant emissions from cars are more than an order of magnitude larger than emissions from rail vehicles. Next come (in descending order) air transport, maritime and inland water transport. The non-compliance of vehicles with environmental requirements, the continued increase in traffic flows, the poor condition of roads - all this leads to a constant deterioration of the environmental situation.

1. Impact of road transport on the environment

Recently, due to the rapid development of road transport, the problems of environmental impact have become much more acute.

Road transport should be considered as an industry associated with the production, maintenance and repair of vehicles, their operation, the production of fuel and lubricants, the development and operation of the road transport network.

From this position, the following negative impacts of cars on the environment can be formulated.

The first group is related to the production of automobiles:

– high resource and raw materials and energy capacity of the automotive industry;

– own negative impact on the environment of the automotive industry (foundry, tool-mechanical production, bench tests, paint and varnish production, tire production, etc.).

The second group is due to the operation of cars:

– fuel and air consumption, emission of harmful exhaust gases;

- Abrasion products of tires and brakes;

– noise pollution of the environment;

– material and human losses as a result of transport accidents.

The third group is associated with the alienation of land for highways, garages and parking lots:

– development of car service infrastructure (gas stations, service stations, car washes, etc.);

– maintenance of transport routes in working condition (use of salt to melt snow in winter periods).

The fourth group combines the problems of regeneration and disposal of tires, oils and other process fluids, the most used cars.

As already noted, the most urgent problem is air pollution.

1.1. Atmospheric pollution by motor vehicles

According to the state report "On the State of the Environment of the Russian Federation in 1995," 10,955 thousand tons of pollutants were emitted into the atmosphere by road transport. Motor transport is one of the main sources of environmental pollution in most large cities, while 90% of the impact on the atmosphere is associated with the operation of motor vehicles on highways, the rest is contributed by stationary sources (workshops, sites, service stations, parking lots, etc.)

In large cities of Russia, the share of emissions from motor transport is commensurate with emissions from industrial enterprises (Moscow and the Moscow Region, St. in some cases it reaches 80% 90% (Nalchik, Yakutsk, Makhachkala, Armavir, Elista, Gorno-Altaisk, etc.).

The main contribution to air pollution in Moscow is made by vehicles, the share of which in the total emission of pollutants from stationary and mobile sources increased from 83.2% in 1994 to 89.8% in 1995.

The motor vehicle fleet of the Moscow region has approximately 750 thousand vehicles (of which 86% are in individual use), the emission of pollutants from which is about 60% of the total emissions into the atmospheric air.

The contribution of motor transport to the pollution of the air basin of St. Petersburg exceeds 200 thousand tons/year, and its share in total emissions reaches 60%.

The exhaust gases of automobile engines contain about 200 substances, most of which are toxic. In the emissions of carburetor engines, the main share of harmful products is carbon monoxide, hydrocarbons and nitrogen oxides, and in diesel engines - nitrogen oxides and soot.

The main reason for the adverse impact of vehicles on the environment remains the low technical level of the rolling stock in operation and the lack of an exhaust gas aftertreatment system.

Indicative is the structure of sources of primary pollution in the United States, presented in Table 1, from which it can be seen that road transport emissions for many pollutants are dominant.

The impact of car exhaust gases on public health. The exhaust gases of internal combustion engines (EGD) contain a complex mixture of more than 200 compounds. These are mainly gaseous substances and a small amount of solid particles in suspension. A gas mixture of solid particles in suspension. The gas mixture consists of inert gases passing through the combustion chamber unchanged, combustion products and unburned oxidizer. Solid particles are fuel dehydrogenation products, metals, and other substances that are contained in the fuel and cannot be burned. According to the chemical properties, the nature of the impact on the human body, the substances that make up OG are divided into non-toxic (N 2, O 2, CO 2, H 2 O, H 2) and toxic (CO, C m H n, H 2 S, aldehydes and others).

The variety of ICE exhaust compounds can be reduced to several groups, each of which combines substances that are more or less similar in their effect on the human body or are related in chemical structure and properties.

Non-toxic substances are included in the first group.

The second ipyrare includes carbon monoxide, the presence of which in large quantities up to 12% is typical for the exhaust gas of gasoline engines (BD) when operating on rich air-fuel mixtures.

The third group is formed by nitrogen oxides: oxide (NO) and dioxide (NO:). Of the total amount of nitrogen oxides, the DU EG contains 98–99% NO and only 12% N02, and diesel engines 90 and 100%, respectively.

The fourth, most numerous group includes hydrocarbons, among which representatives of all homologous series were found: alkanes, alkenes, alkadienes, cyclic hydrocarbons, including aromatic hydrocarbons, among which there are many carcinogens.

The fifth group consists of aldehydes, with formaldehyde accounting for 60%, aliphatic aldehydes 32%, and aromatic 3%.

The sixth group includes particles, the main part of which is soot, solid carbon particles formed in a flame.

Of the total amount of organic components contained in the ICE exhaust gas in a volume of more than 1 %, saturated hydrocarbons account for 32%, unsaturated 27.2%, aromatic 4%, aldehydes, ketones 2.2%. lead (when using tetraethyl lead (TES) as an antiknock agent).

So far, about 75 % gasoline produced in Russia are leaded and contain from 0.17 to 0.37 g/l of lead. There is no lead in diesel transport emissions, however, the content of a certain amount of sulfur in diesel fuel causes the presence of 0.003 0.05% sulfur dioxide in the exhaust gas. Thus, motor transport is a source of emissions into the atmosphere of a complex mixture of chemical compounds, the composition of which depends not only on the type of fuel, type of engine and its operating conditions, but also on the effectiveness of emission control. The latter especially stimulates measures to reduce or neutralize toxic components of exhaust gases.

Once in the atmosphere, the components of the ICE exhaust gas, on the one hand, are mixed with pollutants present in the air, on the other hand, they undergo a series of complex transformations leading to the formation of new compounds. At the same time, the processes of dilution and removal of pollutants from the atmospheric air by wet and dry planting on the ground are underway. Due to the huge variety of chemical transformations of pollutants in the atmospheric air, their composition is extremely dynamic.

The risk of harm to the body from a toxic compound depends on three factors: the physical and chemical properties of the compound, the dose interacting with the tissues of the target organ (the organ that is harmed by the toxicant), and the time of exposure, as well as the biological response of the body to exposure to the toxicant.

If the physical state of air pollutants determines their distribution in the atmosphere, and when inhaled with air - in the respiratory tract of an individual, then the chemical properties ultimately determine the mutagenic potential of the toxicant. Thus, the solubility of a toxicant determines its different placement in the body. Compounds soluble in biological fluids are quickly transferred from the respiratory tract throughout the body, while insoluble compounds are retained in the respiratory tract, in the lung tissue, adjacent lymph nodes, or, moving towards the pharynx, are swallowed.

Inside the body, the compounds undergo metabolism, during which their excretion is facilitated, and toxicity is also manifested. It should be noted that the toxicity of the resulting metabolites can sometimes exceed the toxicity of the parent compound, and generally complements it. The balance between metabolic processes that increase toxicity, reduce it, or favor the elimination of compounds is an important factor in the sensitivity of an individual to toxic compounds.

The concept of "dose" to a greater extent can be attributed to the concentration of the toxicant in the tissues of the target organ. Its analytical definition is quite difficult, since it is necessary, along with the identification of the target organ, to understand the mechanism of interaction of the toxicant at the cellular and molecular level.

The biological response to the action of OG toxicants includes numerous biochemical processes, which are at the same time under complex genetic control. Summing up such processes, determine the individual susceptibility and, accordingly, the result of exposure to toxic substances.

Below are the data of studies of the impact of individual components of the ICE exhaust gas on human health.

Carbon monoxide (CO) is one of the predominant components in the complex composition of vehicle exhaust gases. Carbon monoxide is a colorless, odorless gas. The toxic effect of CO on the human body and warm-blooded animals is that it interacts with hemoglobin (Hb) of the blood and deprives it of the ability to perform the physiological function of oxygen transfer, i.e. the alternative reaction that occurs in the body when exposed to an excessive concentration of CO leads primarily to a violation of tissue respiration. Thus, O 2 and CO compete for the same amount of hemoglobin, but the affinity of hemoglobin for CO is about 300 times greater than for O 2, so CO is able to displace oxygen from oxyhemoglobin. The reverse process of dissociation of carboxyhemoglobin proceeds 3600 times slower than that of oxyhemoglobin. In general, these processes lead to a violation of oxygen metabolism in the body, oxygen starvation of tissues, especially cells of the central nervous system, i.e. carbon monoxide poisoning of the body.

The first signs of poisoning (headache in the forehead, fatigue, irritability, fainting) appear at 20-30% conversion of Hb to HbCO. When the transformation reaches 40 - 50%, the victim faints, and at 80% death occurs. Thus, long-term inhalation of CO at a concentration of more than 0.1% is dangerous, and a concentration of 1% is fatal if exposed for several minutes.

It is believed that the effect of ICE exhaust gas, the main share of which is CO, is a risk factor in the development of atherosclerosis and heart disease. The analogy is related to the increased morbidity and mortality of smokers, who expose the body to prolonged exposure to cigarette smoke, which, like ICE exhaust gas, contains a significant amount of CO.

nitrogen oxides. Of all known nitrogen oxides in the air of highways and the area adjacent to them, oxide (NO) and dioxide (NO 2) are mainly determined. In the process of fuel combustion in the internal combustion engine, NO is first formed, the concentration of NO 2 is much lower. During the combustion of fuel, three ways of NO formation are possible:

1. 
   At high temperatures inherent in a flame, atmospheric nitrogen reacts with oxygen, forming thermal NO, the rate of formation of thermal NO is much less than the rate of combustion of the fuel and it increases with the enrichment of the air-fuel mixture;
2. 
   The presence of compounds with chemically bound nitrogen in the fuel (in the asphaltene fractions of purified fuel, the nitrogen content is 2.3% by mass, in heavy fuels 1.4%, in crude oil the average nitrogen content by mass is 0.65%) causes the formation of fuel during combustion. N0. Oxidation of nitrogen-containing compounds (in particular, simple NH3, HCN) occurs! quickly, in a time comparable to the combustion reaction time. The yield of fuel NO depends little on temperature;
3. 
   Formed at the flame fronts N0 (not from atmospheric N2 and Oi) called fast. It is believed that the regime proceeds through intermediate substances containing CN groups, the rapid disappearance of which near the reaction zone leads to the formation of NO.

2 NO + O2 -» 2NO 2; NO + Oz

At the same time, at solar noon, photolysis of NO2 occurs with the formation of NO:

N0 2 + h -> N0 + O.

Thus, in the atmospheric air there is a conversion of NO and NO2, which involves organic pollutant compounds in interaction with nitrogen oxides with the formation of very toxic compounds. for example, nitro compounds, nitro-PAHs (polycyclic aromatic hydrocarbons), etc.

Exposure to nitrogen oxides is mainly associated with irritation of the mucous membranes. Prolonged exposure leads to acute respiratory diseases. In acute nitrogen oxide poisoning, pulmonary edema may occur. Sulfur dioxide. The proportion of sulfur dioxide (SO2) in the exhaust gas of internal combustion engines is small compared to oxides of carbon and nitrogen and depends on the sulfur content in the fuel used, during the combustion of which it is formed. Particularly noteworthy is the contribution of vehicles with diesel engines to air pollution with sulfur compounds, because. the content of sulfur compounds in the fuel is relatively high, the scale of its consumption is huge and is increasing every year. Elevated levels of sulfur dioxide can often be expected near idling vehicles, namely in parking lots, near regulated intersections.

Sulfur dioxide is a colorless gas, with a characteristic suffocating smell of burning sulfur, quite easily soluble in water. In the atmosphere, sulfur dioxide causes water vapor to condense into a mist even under conditions where the vapor pressure is less than that required for condensation. Dissolving in the moisture available on plants, sulfur dioxide forms an acidic solution that has a detrimental effect on plants. Coniferous trees located near cities are especially affected by this. In higher animals and humans, sulfur dioxide acts primarily as a local irritant of the mucous membrane of the upper respiratory tract. The study of the process of absorption of SO2 in the respiratory tract by inhalation of air containing certain doses of this toxicant showed that the countercurrent process of adsorption, desorption and removal from the body of SO2 after desorption during exhalation reduces its total load in the upper respiratory tract. In the course of further research in this direction, it was found that an increase in the specific response (in the form of bronchospasm) to the effect of SO2 correlates with the size of the area of ​​the respiratory tract (in the pharyngeal region) that adsorbed sulfur dioxide.

It should be noted that people with respiratory diseases are very sensitive to the effects of exposure to air contaminated with SO2. Particularly sensitive to inhalation of even the lowest doses of SO2 are asthmatics who develop acute, sometimes symptomatic bronchospasm during even brief exposure to low doses of sulfur dioxide.

The study of the synergistic effect of exposure to oxidants, in particular, ozone and sulfur dioxide, revealed a significantly greater toxicity of the mixture compared to individual components.

Lead. The use of lead-containing anti-knock fuel additives has led to the fact that motor vehicles are the main source of lead emissions into the atmosphere in the form of an aerosol of inorganic salts and oxides. The share of lead compounds in the ICE exhaust gas is from 20 to 80% of the mass of emitted particles and it varies depending on the particle size and engine operation mode.

The use of leaded gasoline in heavy traffic leads to significant lead pollution of the atmospheric air, as well as soil and vegetation in areas adjacent to highways.

The replacement of TES (tetraethyl lead) with other more harmless antiknock compounds and the subsequent gradual transition to unleaded gasoline help to reduce the lead content in the atmospheric air.

In our country, unfortunately, the production of leaded gasoline continues, although a transition to the use of unleaded gasoline by motor vehicles is envisaged in the near future.

Lead enters the body either with food or with air. Symptoms of lead intoxication have been known for a long time. Thus, under conditions of long-term industrial contact with lead, the main complaints were headache, dizziness, increased irritability, fatigue, and sleep disturbance. Particles of lead compounds with a size of less than 0.001 mm can enter the lungs. Larger ones linger in the nasopharynx and bronchi.

According to the data, from 20 to 60% of inhaled lead is located in the respiratory tract. Most of it is then removed from the respiratory tract by the flow of body fluids. Of the total amount of lead absorbed by the body, atmospheric lead accounts for 7-40%.

There is still no single idea about the mechanism of action of lead on the body. It is believed that lead compounds act as a protoplasmic poison. At an early age, lead exposure causes irreversible damage to the central nervous system.

organic compounds. Among the many organic compounds identified in the exhaust gas of the internal combustion engine, 4 classes are distinguished in toxicological terms:

Aliphatic hydrocarbons and products of their oxidation (alcohols, aldehydes, acids);

Aromatic compounds, including heterocycles and their oxidized products (phenols, quinones);

• 
  alkyl-substituted aromatic compounds and their oxidized
• 
  products (alkylphenols, alkylquinones, aromatic carboxyaldehydes, carboxylic acids);

It should be noted that toxicological studies of most inhaled compounds included in the list of atmospheric pollutants were carried out mainly in pure form, although most of the organic compounds emitted into the atmosphere are adsorbed on solid, relatively inert and insoluble particles. Particulate matter is soot, a product of incomplete combustion of fuel, particles of metals, their oxides or salts, as well as dust particles, always present in the atmosphere. It is known that 20 30 % particulate matter in urban air are microparticles (less than 10 microns in size) emitted from the exhaust gases of trucks and buses.

The emission of solid particles from the exhaust gas depends on many factors, among which the design features of the engine, its mode of operation, technical condition, and the composition of the fuel used should be highlighted. The adsorption of organic compounds contained in the ICE exhaust gas on solid particles depends on the chemical properties of the interacting components. In the future, the degree of toxicological effects on the body will depend on the rate of separation of associated organic compounds and solid particles, the rate of megabolism and neutralization of organic toxicants. Particulate matter can also affect the body, and the toxic effect can be as dangerous as cancer.

Oxidizers. The composition of GO compounds that enter the atmosphere cannot be considered in isolation due to the ongoing physical and chemical transformations and interactions that lead, on the one hand, to the transformation of chemical compounds, and on the other hand, to their removal from the atmosphere. The complex of processes occurring with primary ICE emissions includes:

Dry and wet deposition of gases and particles;

Chemical reactions of gaseous emissions of EG of internal combustion engines with OH, ICHO3, radicals, Oz, N2O5 and gaseous HNO3; photolysis;

Reactions of organic compounds adsorbed on particles with compounds in the gas phase or in adsorbed form; - reactions of various reactive compounds in the aqueous phase, leading to the formation of acid precipitation.

The process of dry and wet precipitation of chemical compounds from ICE emissions depends on the particle size, the adsorption capacity of the compounds (adsorption and desorption constants), and their solubility. The latter is especially important for compounds that are highly soluble in water, the concentration of which in the atmospheric air during rain can be brought to zero.

The physical and chemical processes occurring in the atmosphere with the initial EG compounds of the internal combustion engine, as well as their impact on people and animals, are closely related to their lifetime in atmospheric air.

Thus, in the hygienic assessment of the impact of ICE exhaust gas on public health, it should be taken into account that the compounds of the primary composition of exhaust gases in the atmospheric air undergo various transformations. During photolysis of GO of ICE, the dissociation of many compounds (NO2, O2, O3, HCHO, etc.) occurs with the formation of highly reactive radicals and ions that interact both with each other and with more complex molecules, in particular, with compounds of the aromatic series, which quite a lot in OG.

As a result, dangerous air pollutants such as ozone, various inorganic and organic peroxide compounds, amino-, nitro- and nitroso compounds, aldehydes, acids, etc. appear among the compounds newly formed in the atmosphere. Many of them are strong carcinogens.

Despite extensive information about the atmospheric transformations of chemical compounds that make up GO, these processes have not been fully studied to date, and, consequently, many products of these reactions have not been identified. However, even what is known, in particular, about the impact of photooxidants on public health, especially on asthmatics and people weakened by chronic lung diseases, confirms the toxicity of ICE exhaust gases.

Standards for emissions of harmful substances from exhaust gases of cars- one of the main measures is to reduce the toxicity of automobile emissions, the ever-increasing amount of which has a threatening effect on the level of air pollution in large cities and, accordingly, on human health. Attention was first drawn to automobile emissions in the study of the chemistry of atmospheric processes (1960s, USA, Los Angeles), when it was shown that photochemical reactions of hydrocarbons and nitrogen oxides can form many secondary pollutants that irritate the mucous membranes of the eyes, airways and impair visibility.

Due to the fact that the main contribution to the total air pollution with hydrocarbons and nitrogen oxides is made by ICE exhaust gases, the latter were recognized as the cause of photochemical smog, and the society faced the problem of legislative limitation of harmful automobile emissions.

As a result, in the late 1950s, California began developing emission standards for pollutants contained in vehicle air quality as part of state air quality legislation.

The purpose of the standard was "to establish maximum allowable levels of pollutants in vehicle emissions, linked to the protection of public health, the prevention of irritation of the senses, deterioration of visibility and damage to vegetation."

In 1959, the world's first standards were established in California - limit values ​​for exhaust gas CO and CmHn, in 1965 - the law on the control of air pollution by motor vehicles was adopted in the USA, and in 1966 - the US state standard was approved.

The state standard was, in essence, a technical task for the automotive industry, stimulating the development and implementation of many measures aimed at improving the automotive industry.

At the same time, this allowed the US Environmental Protection Agency to regularly tighten standards that reduce the quantitative content of toxic components in exhaust gases.

In our country, the first state standard for the restriction of harmful substances in the exhaust gases of cars with gasoline engines was adopted in 1970.

In subsequent years, various regulatory and technical documents were developed and are in force, including industry and state standards, which reflect a gradual reduction in the emission standards for harmful exhaust gas components.

1.2. Reducing emissions from vehicles

At present, many methods have been proposed to reduce harmful emissions from motor vehicles: the use of new (H 2 , CH4 and other gas fuels) and combined fuels, electronics for controlling engine operation on lean mixtures, improving the combustion process (prechamber-flare), catalytic purification of exhaust gases, etc.

When creating catalysts, two approaches are used - systems are developed for the oxidation of carbon monoxide and hydrocarbons and for complex ("three-component") purification based on the reduction of nitrogen oxides with carbon monoxide in the presence of oxygen and hydrocarbons. Complete purification is most attractive, but expensive catalysts are required. In two-component purification, platinum-palladium catalysts showed the highest activity, and in three-component purification, platinum-rhodium or more complex catalysts containing platinum, rhodium, palladium, cerium on granular alumina.

For a long time, the impression was created that the use of diesel engines contributes to environmental cleanliness. However, despite the fact that diesel engines are more economical, they emit no more substances such as CO, NO X than gasoline engines, they emit much more soot (the purification of which still has no cardinal solutions), sulfur dioxide. Combined with the noise generated, diesel engines are no more environmentally friendly than gasoline engines.

The shortage of liquid fuel of petroleum origin, as well as a sufficiently large amount of harmful substances in the exhaust gas during its use, contribute to the search for alternative fuels. Taking into account the specifics of road transport, five main conditions for the prospects of new types of fuel are formulated: the availability of sufficient energy and raw materials resources, the possibility of mass production, technological and energy compatibility with transport power plants, acceptable toxic and environmental indicators of the energy use process, safety and harmlessness of operation. Thus, a promising automotive fuel can be that chemical energy source that allows solving the energy and environmental problem to some extent.

According to experts, hydrocarbon gases of natural origin and synthetic fuel-alcohols satisfy these requirements to the greatest extent. In a number of works, hydrogen and nitrogen-containing compounds such as ammonia and hydrazine are named as promising fuels. Hydrogen as a promising automotive fuel has long attracted the attention of scientists, due to its high energy performance, unique kinetic characteristics, the absence of most harmful substances in combustion products, and a virtually unlimited resource base.

The hydrogen engine is environmentally friendly, because during the combustion of hydrogen-air mixtures, water vapor is formed and the formation of any toxic substances is excluded, except for nitrogen oxides, the emission of which can also be reduced to an insignificant level.

Hydrogen is obtained mainly during the processing of natural gas and oil, gasification of coal under pressure on steam-oxygen blast is considered as a promising method, and the use of excess energy from power plants to produce hydrogen by electrolysis of water is also being studied.

Numerous schemes for the possible use of hydrogen in a car are divided into two groups: as the main fuel and as an additive to modern motor fuels, and hydrogen can be used in its pure form or as part of secondary energy carriers. Hydrogen as the main fuel is a distant prospect associated with the transition of motor transport to a fundamentally new energy base.

More realistic is the use of hydrogen additives, which improve the economic and toxic performance of automobile engines.

Of greatest interest as secondary energy carriers is the accumulation of hydrogen in the composition of metal hydrides. To charge a metal hydride battery through the hydride of some metals at low temperatures, I pass! hydrogen and remove heat. When the engine is running, the hydride is heated by hot water or exhaust gas with the release of hydrogen.

As studies have shown on transport installations, it is most expedient to use a combined storage system that includes iron-titanium and magnesium-nickel hydrides.

Compared to hydrogen, which is currently considered as a promising type of gas motor fuel (since industrial methods for its production in sufficient quantities for mass use have not been developed), natural and petroleum hydrocarbon gases are the most acceptable alternative fuels for motor vehicles that could cover the ever-increasing shortage of liquid motor fuels.

Tests of operation of engines on liquefied gas show that, compared with the use of gasoline, EG contains 24 times less CO, 1.4 -1.8 times less NO X . At the same time, hydrocarbon emissions, especially when operating at low speeds and low loads, increase by 1.2 - 1.5 times.

The introduction of gas fuel in road transport is stimulated not only by the desire to diversify energy sources in the face of an increasing shortage of oil, as well as the environmental friendliness of this type of fuel, which is extremely important in the context of tightening toxic emissions standards, but also by the absence of any serious technological processes for preparing this type of fuel for use.

From the point of view of environmental cleanliness, an electric car is the most promising. The current problems (creation of reliable electrochemical power sources, high cost, etc.) may well be solved in the future.

The general ecological state in cities is also determined by the proper organization of vehicle traffic. The greatest emission of harmful substances occurs during braking, acceleration, additional maneuvering. Therefore, the creation of road "junctions", high-speed highways with a network of underground passages, the correct installation of traffic lights, traffic control according to the "green wave" principle in many respects reduce the release of harmful substances into the atmosphere and contribute to the safety of transport.

Noise from road transport - this is the most common type of adverse environmental impact on the human body. In cities, up to 60% of the population lives in areas with increased noise levels associated specifically with road transport. The noise level depends on the structure of the traffic flow (share of trucks), traffic intensity, quality of the road surface, the nature of the development, the behavior of the driver while driving, etc.

Reducing the noise level from road transport can be achieved on the basis of the technical improvement of the car, anti-noise enclosing structures and green spaces. The rational organization of traffic, as well as the restriction of car traffic in the city, can help solve the problem of noise reduction.

1.3. The influence of the transport and road complex on biocenoses

The anthropic effect of TDA is due to numerous factors. Among them, however, two are predominant:

Land acquisition and related disruption of natural systems,

Environmental pollution. Land acquisition is carried out in accordance with SNiPs for road design. Land acquisition rates take into account their value and depend on the category of the projected road.

Thus, 2.1-2.2 ha of agricultural land or 3.3-3.4 ha of non-agricultural land are allocated per 1 km of a highway of the V (lowest) category with one lane, for roads of the 1st category - 4.7-6.4 ha or 5.5-7.5 ha, respectively.

In addition, significant areas are allocated for car parking, road crossings, interchanges, etc. For example, to accommodate transport interchanges at different levels at the intersection of highways, from 15 hectares are allotted per interchange in the case of the intersection of two two-lane roads to 50 hectares in the case of the intersection of two eight-lane roads.

These land allotment lines ensure the quality of construction and operation of roads, and hence traffic safety. Therefore, they should be considered as inevitable losses with an increase in the level of civilization.

The road network of the Russian Federation is about 930 thousand km, incl. 557 thousand km of public use. With a conditional allotment of 4 hectares of land per 1 km, it turns out that 37.2 thousand km2 are occupied by roads.

The car park in Russia is about 20 million units (of which only 2% of cars use gas fuel). About 4 thousand large and medium-sized motor transport enterprises, many small ones, which are mainly privately owned, are engaged in transportation.

Of all substances polluting the atmosphere, 53% are formed by various types of vehicles. Of these, 70% is accounted for by road transport (I.I. Mazur, 1996). The total emission of harmful substances into the atmosphere by mobile and stationary sources of TDA is about 18 million tons per year. The greatest danger is CO, hydrocarbons, NO 2 , soot, SO 2 Pb, dusty substances of various origins.

TDK enterprises annually release millions of tons of industrial wastewater into the environment. The most significant of them are suspended solids, oil products, chlorides and household water.

Pollution of the environment by transport and TDK enterprises is not equivalent, however, their combined impact on the environment is colossal and is considered to be the most significant today.

Among the reasons for the decisive contribution of TDC to the environmental pollution of the Russian Federation, the following can be distinguished:

1. There is no effective system for regulating the technogenic impact of TDK on the environment;

2. There are no manufacturers' guarantees for the stability of environmental performance;

3. Insufficient control over the quality of fuels and lubricants produced and sold to consumers;

4. Low level of repair work at the TDK and, in particular, road transport (according to I.I. Mazur et al., 1996);

5. The low legal and moral-cultural level of a significant part of the persons serving the TDC of the Russian Federation. To improve the current situation in the Russian Federation, a targeted comprehensive program "Ecological Safety of Russia" has been developed and is being implemented.

1.3.2 Consequences of TDC influence on biota of ecosystems

The impact of TDC on the biosphere or individual ecosystems is only a part of the anthropogenic impact on the environment. Therefore, it is characterized by all the features determined by the consequences of scientific and technological progress, urbanization and agglomeration. However, there is a special feature.

The actions of transport systems and transport on the environment can be divided into:

1. Permanent

2. Destroying

3. Damaging.

A permanent effect on the ecosystem leads to periodic changes that do not bring it out of balance. This applies to some types of pollution (such as moderate acoustic) or increased episodic recreational load.

In accordance with the Law (rule), 1% change in the energy of a natural system up to 1% does not bring it out of equilibrium. The ecosystem is capable of self-preservation and self-recovery under the specified conditions.

The destructive effect on the biota leads to its complete or significant extermination. Species diversity and the amount of biomass are sharply reduced. It is carried out during the construction of transport systems and TDK enterprises, as well as as a result of man-made accidents.

In addition to direct negative consequences, it is obvious that any economic action that leads to the direct destruction of the environment leads to undesirable consequences that ultimately affect microeconomic and social processes. This pattern was first expressed by P. Dancero (1957) and is called the Law of feedback of interaction "man-biosphere". B. Commoner in this regard expressed one of his environmental "postulates" - "you have to pay for everything." And, finally, the damaging effect on ecosystems manifests itself in conditions when the energy change exceeds 1% of the energy potential of the system (see above), but does not destroy it. In conditions of TDK, it manifests itself in the construction and operation of transport systems.

Nature is constantly striving to restore the lost balance, using the mechanism of succession for this, and man is trying to maintain the benefits gained, for example, by repairing and restoring communications and the territories serving them.

What are the consequences of damage to natural ecosystems by TDCs for the biota of ecosystems?

1. Some species of living beings may disappear. All of them are renewable resources for humans. But according to the Law of irreversibility of the interaction "man-biosphere" (P.Dancero, 1957), in case of irrational use of nature, they become non-renewable and exhaustible.

2. The number of existing populations is decreasing. One of the reasons for this for producers is the decrease in soil fertility and environmental pollution. It has been established that heavy metals, traditional road pollutants, are found in quantities exceeding the permissible limits at a distance of 100 m from the road. They delay the development of many plant species, reduce their ontogeny. For example, lime trees (Tilia L.) growing along highways die 30-50 years after planting, while in city parks they grow for 100-125 years (E.I. Pavlova, 1998). The number of consumers is decreasing due to the reduction of food and water sources, as well as opportunities for movement and reproduction (see lecture No. 5).

3. The integrity of natural landscapes is violated. Since all ecosystems are interconnected, damage or destruction of at least one of them as a result of the impact of TDCs or other structures inevitably affects the existence of the biosphere as a whole.

Note: this lecture is intended for students studying the specialization "Engineering Environmental Protection in Transport".

2. Problems of urban transport

The central problem of urban ecology is air pollution by vehicles, the "contribution" of which ranges from 50 to 90%. (The share of motor transport in the global balance of air pollution is -13.3%.)

2.1. The impact of vehicles on the urban environment

A car burns a significant amount of oxygen and emits an equivalent amount of carbon dioxide into the atmosphere. Car exhaust contains about 300 harmful substances. The main air pollutants are carbon oxides, hydrocarbons, nitrogen oxides, soot, lead, and sulfur dioxide. Among the hydrocarbons, the most dangerous are benzopyrene, formaldehyde, and benzene (Table 45).

During the operation of the car, rubber dust, which is formed due to the abrasion of tires, also enters the atmosphere. When using gasoline with the addition of lead compounds, the car pollutes the soil with this heavy metal. There is pollution of water bodies when washing cars and when used engine oil gets into the water.

Asphalt roads are needed for the movement of cars, a significant area is occupied by garages and parking lots. The greatest harm is caused by private cars, since environmental pollution when traveling by bus in terms of one passenger is about 4 times less. Cars (and other vehicles, especially trams) are a source of noise pollution.

2.2. World level of motorization

There are about 600 million cars in the world (in China and India - 600 million bicycles). The leader in motorization is the United States, where there are 590 cars per 1,000 people. In different cities of the United States, one resident uses from 50 to 85 gallons of gasoline per year to travel around the city, which costs 600-1000 dollars (Brown, 2003). In other developed countries, this figure is lower (in Sweden - 420, in Japan - 285, in Israel - 145). At the same time, there are countries with a low level of motorization: in South Korea, there are 27 cars per 1,000 people, in Africa - 9, in China and India - 2.

Reducing the number of private cars can be achieved with higher prices for vehicles equipped with electronic environmental controls and with an environmentally friendly tax system. For example, in the US, an ultra-high "green" tax on motor oil has been introduced. In a number of European countries, parking fees are constantly increasing.

In Russia, over the past 5 years, the car park has increased by 29%, and their average number per 1,000 Russians has reached 80

(in large cities - over 200). If the current trends in urban motorization continue, this could lead to a sharp deterioration in the state of the environment.

A special task, especially relevant for Russia, is to reduce the number of obsolete cars that continue to be used and pollute the environment more than new ones, as well as the recycling of cars entering landfills.

2.3. Ways of greening urban transport

Reducing the negative impact of the car on the environment is an important task for urban ecology. The most radical way to solve the problem is to reduce the number of cars and replace them with bicycles, however, as noted, it continues to increase throughout the world. And therefore, for the time being, the most realistic measure to reduce harm from a car is to reduce fuel costs by improving internal combustion engines. Work is underway to create car engines from ceramics, which will increase the combustion temperature of fuel and reduce the amount of exhaust gases. Japan and Germany are already using cars equipped with special electronic devices that ensure more complete combustion of fuel. Ultimately, all this will reduce fuel consumption per 100 km of track by about 2 times. (In Japan, Toyota is preparing to release a car model with a fuel consumption of 3 liters per 100 kilometers.)

Fuel is being ecologized: gasoline without lead additives and special additives-catalysts for liquid fuel are used, which increases the completeness of its combustion. Atmospheric pollution by cars is also reduced by replacing gasoline with liquefied gas. New types of fuel are also being developed.

Electric vehicles, which are being developed in many countries, do not have disadvantages of cars with internal combustion engines. The production of such vans and cars has begun. To serve the urban economy, electric minitractors are being created. However, in the coming years, electric vehicles are unlikely to play a significant role in the global car fleet, as they require frequent recharging of batteries. In addition, the disadvantage of an electric vehicle is the inevitable pollution of the environment with lead and zinc, which occurs during the production and processing of batteries.

Various variants of hydrogen fuel vehicles are being developed, as a result of which water is formed as a result of combustion, and thus there is no pollution of the environment at all.

Wednesdays. Since hydrogen is an explosive gas, a number of complex technological safety problems must be solved in order to use it as a fuel.

As part of the development of physical options for solar energy, models of solar vehicles are being developed. While these vehicles are going through the stages of experimental samples, nevertheless, their rallies are regularly held in Japan, in which Russian creators of new vehicles also participate. The cost of champion models is still 5-10 times higher than the cost of the most prestigious car. The disadvantage of solar cars is the large size of solar cells, as well as dependence on the weather (the solar car is supplied with a battery in cases where the sun is hidden behind clouds).

In large cities, bypass roads are being built for intercity buses and freight transport, as well as underground and elevated transport routes, since a lot of exhaust gases are released into the atmosphere when traffic jams occur at street intersections. In a number of cities, the movement of cars is organized according to the "green wave" type.

2.4. Municipal experience in personal vehicle mileage management

A large number of cars in many cities of the world not only leads to air pollution, but also causes traffic disruption and the formation of traffic jams, which is accompanied by excessive consumption of gasoline and loss of time for drivers. Particularly impressive are the data for US cities, where the level of motorization of the population is very high. In 1999, the total cost of traffic congestion in the United States amounted to $300 per year per American, or $78 billion in total. In some cities, these figures are especially high: in Los Angeles, Atlanta and Houston, each car owner loses " traffic jams for more than 50 hours a year and consumes an additional 75-85 gallons of gasoline, which costs him $850-1000 (Brown, 2003).

Municipal authorities are doing everything possible to reduce these losses. So, in the USA, a number of states encourage joint trips of neighbors in the same car to work. In Milan, to reduce the mileage of private cars, it is practiced to use them every other day: on even days, cars with even numbers are allowed to leave, and on odd days, with odd ones. In Europe* since the late 1980s, the popularity of “shared car parks” has been on the rise. The European network of such parks today includes 100,000 members in 230 cities in Germany, Austria, Switzerland and the Netherlands. Each collective car replaces 5 personal ones, and in general, the total mileage is reduced by more than 500 thousand km annually.

2.5. The role of public transport

In many cities, it was possible to achieve a reduction in the mileage of private cars due to the perfect organization of the work of public transport (the specific fuel consumption in this case decreases by about 4 times). The share of public transport is maximum in Bogota (75%), Curitiba (72%), Cairo (58%), Singapore (56%), Tokyo (49%). In most US cities, the role of public transport does not exceed 10%, but in New York this figure reaches 30% (Brown, 2003).

The most perfect organization of public transport is in Curitiba (Brazil). In this city of 3.5 million people, three-section buses run on five radial routes, two-section buses run on three circular routes, and single-section buses run on shorter routes. The movement takes place strictly according to the schedule, the stops are equipped so that passengers quickly get on and off the buses. As a result, despite the fact that the number of private cars among residents is no less than in other cities, they rarely use them, preferring public transport. In addition, the number of bicycles in the city is increasing year by year, and the length of cycle paths has exceeded 150 km. Since 1974, the population of the city has doubled, and the flow of cars on the roads has decreased by 30%.

2.6. The problem of recycling old cars

End-of-life vehicles are one of the most voluminous and difficult-to-recycle household waste fractions (see 7.5). In the countries of the "golden billion" their processing has been established. If earlier it was necessary to pay a significant amount of money for scrapping a car, now it is done free of charge: the cost of recycling an old car is included in the price of a new one. Thus, the costs of disposing of automobile "remains" are borne by manufacturing companies and buyers. In Europe, 7 million cars are processed annually, and all new models include “easy disassembly” into components as a mandatory engineering solution - Renault is the leader in this.

In Russia, the recycling of old cars is still poorly organized (Romanov, 2003). This is one of the reasons why the share of cars older than 10 years in the current fleet exceeds 50%, and they are known to be the main pollutants of the urban environment. The "remains" of old cars are scattered everywhere and pollute the environment. Where the recycling of old cars is organized, it is primitive: either old bodies are pressed into briquettes (in this case, during remelting, the environment is polluted by plastic burning waste), or the heaviest parts of the car are collected as scrap metal, and everything else is thrown into lakes and forests.

Recycling with car fractionation is not only more environmentally friendly, but also cost-effective. Only by recycling batteries can Russia solve the problem of lead supply. In developed countries, no more than 10% of tires end up in landfills, 40% of them are burned to generate energy, the same amount is subjected to deep processing and 10% is ground into crumbs, which are used as a valuable component of road surfaces. In addition, some of the tires are retreaded. With deep processing, 400 liters of oil, 135 liters of gas and 140 kg of steel wire are obtained from each ton of tires.

However, the situation in Russia is beginning to change. The leader is the Moscow region, where a number of industries have been created, which are headed by the Noginsk and Lyubertsy scrap metal processing plants. 500 firms and "firms" were included in the processing process.

It is clear that Russia needs a new legal framework to regulate the fate of old cars.

3. Other modes of transport and their impact on the environment

3.1. Aviation and rocket carriers

Studies of the composition of combustion products of engines installed on Boeing-747 aircraft showed that the content of toxic components in combustion products significantly depends on the engine operating mode.

High concentrations of CO and CnHm (n is the rated engine speed) are typical for gas turbine engines in reduced modes (idling, taxiing, approaching the airport, landing approach), while the content of nitrogen oxides NOx (NO, NO2, N2O5) increases significantly at work in modes close to nominal (takeoff, climb, flight mode).

The total emission of toxic substances by aircraft with gas turbine engines is constantly growing, which is due to an increase in fuel consumption up to 20–30 t/h and a steady increase in the number of aircraft in operation.

Gas turbine emissions have the greatest impact on living conditions at airports and areas adjacent to test stations. Comparative data on emissions of harmful substances at airports show that the receipts from gas turbine engines into the surface layer of the atmosphere are:

Carbon oxides - 55%

Nitrogen oxides - 77%

Hydrocarbons - 93%

Aerosol - 97

The rest of the emissions come from ground vehicles with internal combustion engines.

Air pollution by transport with rocket propulsion systems occurs mainly during their operation before launch, during takeoff and landing, during ground tests during their production and after repair, during storage and transportation of fuel, as well as during refueling of aircraft. The operation of a liquid rocket engine is accompanied by the release of products of complete and incomplete combustion of fuel, consisting of O, NOx, OH, etc.

During the combustion of solid fuels, H2O, CO2, HCl, CO, NO, Cl, as well as Al2O3 solid particles with an average size of 0.1 µm (sometimes up to 10 µm) are emitted from the combustion chamber.

Space Shuttle engines burn both liquid and solid propellants. As the ship moves away from the Earth, the products of fuel combustion penetrate into various layers of the atmosphere, but mostly into the troposphere.

Under launch conditions, a cloud of combustion products, water vapor from the noise suppression system, sand and dust form at the launch system. The volume of combustion products can be determined from the time (usually 20 s) of operation of the facility on the launch pad and in the surface layer. After launch, the high-temperature cloud rises to a height of up to 3 km and moves under the influence of the wind to a distance of 30-60 km, it can dissipate, but can also cause acid rain.

During launch and return to Earth, rocket engines adversely affect not only the surface layer of the atmosphere, but also outer space, destroying the Earth's ozone layer. The scale of the destruction of the ozone layer is determined by the number of launches of rocket systems and the intensity of flights of supersonic aircraft. During the 40 years of the existence of cosmonautics in the USSR and later in Russia, more than 1,800 launches of carrier rockets have been carried out. According to the forecasts of the company Aerospace in the XXI century. to transport cargo into orbit, up to 10 rocket launches per day will be carried out, while the emission of combustion products from each rocket will exceed 1.5 t/s.

According to GOST 17.2.1.01 - 76 emissions into the atmosphere are classified:

According to the aggregate state of harmful substances in emissions, these are gaseous and vaporous (SO2, CO, NOx hydrocarbons, etc.); liquid (acids, alkalis, organic compounds, solutions of salts and liquid metals); solid (lead and its compounds, organic and inorganic dust, soot, resinous substances, etc.);

By mass emission, distinguishing six groups, t/day:

Less than 0.01 incl.;

Over 0.01 to 0.1 incl.;

Over 0.1 to 1.0 incl.;

Over 1.0 to 10 incl.;

Over 10 to 100 incl.;

Over 100.

In connection with the development of aviation and rocket technology, as well as the intensive use of aircraft and rocket engines in other sectors of the national economy, their total emission of harmful impurities into the atmosphere has increased significantly. However, these engines still account for no more than 5% of toxic substances entering the atmosphere from vehicles of all types.

3.2. Ship pollution

In order to reduce gas pollution during diesel operation with metals, soot and other solid impurities, diesel engines and shipbuilders are forced to equip ship power plants and propulsion complexes with exhaust gas cleaning equipment, more efficient separators of oily bilge water, sewage and domestic water purifiers, modern incinerators.

Refrigerators, tankers, gas and chemical carriers, and some other ships are sources of air pollution with freons (nitrogen oxides0 used as a working fluid in refrigeration plants. Freons destroy the ozone layer of the Earth's atmosphere, which is a protective shield for all living things from the harsh ultraviolet radiation.

Obviously, the heavier the fuel used for thermal engines, the more heavy metals it contains. In this regard, the use of natural gas and hydrogen, the most environmentally friendly types of fuel, on ships is very promising. The exhaust gases of diesel engines running on gas fuel practically do not contain solid substances (soot, dust), as well as sulfur oxides, contain much less carbon monoxide and unburned hydrocarbons.

Sulfuric gas SO2, which is part of the exhaust gases, oxidizes to the state of SO3, dissolves in water and forms sulfuric acid, and therefore the degree of harmfulness of SO2 to the environment is twice as high as that of nitrogen oxides NO2, these gases and acids disrupt the ecological balance.

If we take as 100% all the damage from the operation of transport ships, then, as analysis shows, the economic damage from pollution of the marine environment and the biosphere is on average 405%, from vibration and noise of the equipment and the ship's hull - 22%, from corrosion of the equipment and hull -18 %, from the unreliability of transport engines -15%, from the deterioration of the health of the crew -5%.

IMO rules from 1997 limit the maximum sulfur content in fuel to 4.5%, and in limited water areas (for example, in the Baltic region) to 1.5%. As for nitrogen oxides Nox, for all new ships under construction, limit values ​​for their content in exhaust gases are set depending on the speed of the diesel crankshaft, which reduces atmospheric pollution by 305. At the same time, the value of the upper limit for the content of Nox, for low-speed diesel engines, is higher, than medium and high-speed ones, since they have more time to burn fuel in the cylinders.

As a result of the analysis of all the negative factors affecting the environment during the operation of transport ships, it is possible to formulate the main measures aimed at reducing this impact:

The use of higher quality grades of motor fuels, as well as natural gas and hydrogen as an alternative fuel;

Optimization of the working process in a diesel engine in all operating modes with the widespread introduction of electronically controlled fuel injection systems and variable valve timing and fuel supply, as well as optimization of oil supply to diesel cylinders;

Complete prevention of fires in utilization boilers by equipping them with temperature control systems in the boiler cavity, fire extinguishing, soot blowing;

Mandatory equipment of ships with technical means for quality control of exhaust gases escaping into the atmosphere and oily, waste and domestic waters removed overboard;

Complete prohibition of the use on ships for any purpose of nitrogen-containing substances (in refrigeration plants, fire fighting systems, etc.)

Leak prevention in gland and flange connections and ship systems.

Efficient use of shaft-generator units as part of ship power systems and transition to the operation of diesel generators with variable speed.