Ecology. Cheat sheet: briefly, the most important

Free technical library

Lecture notes, cheat sheets
Free library / Directory / Lecture notes, cheat sheets

Ecology. Cheat sheet: briefly, the most important

Lecture notes, cheat sheets

Directory / Lecture notes, cheat sheets

Comments on the article

Table of contents

Basic concepts (terms) of ecology. Consistency
Environment and environmental factors, their classification
Living environments and adaptations of organisms to them
Biosphere as a global ecosystem
Organization (structure) of ecosystems
Ecosystem Stability and Resilience
Agrocenoses and natural ecosystems
Dynamics and development of ecosystems. Successions
Population structure
Population dynamics. homeostasis
Social and Applied Ecology
Concepts and terms used in social and applied ecology
Regulations (laws, rules, principles) used in social and applied ecology
Man's place in biospheric processes
Cycles of substances and their violation by man
Environmental crises and environmental situations
Human environment and its components
Modern ecological crisis and its features. The scale of human impact on the environment and the biosphere
Basic concepts of demography
Features of the demography of developed and developing countries
Demographic pyramids and population forecast
The concept of "natural resources", their classification. Problems of exhaustibility of natural resources
Resource use and pollution issues
The main properties of the atmosphere and human impact on it
The problem of the greenhouse effect
The ozone problem
The problem of acid rain
Water as a substance, resource and condition of life
3water reserves on Earth and its global cycle
The problem of pollution or quality depletion of water.
Environmental consequences of the use of mineral fertilizers and pesticides
Biological control measures for unwanted organisms
Ecological consequences of modern animal husbandry practices
Forest fund of the planet and Russia. Parameters and criteria for forest management
The most important ecological functions of forests
Problems of forest sustainability under anthropogenic pressures. Tropical Forest Specific Problems
biological diversity. Red Books. Specially Protected Areas
Environmental monitoring
Environmental problems of cities and settlements
Cities and disasters
Some ways of solving environmental problems of cities.
Environmental problems of energy
Environmental problems of nuclear power
Alternative energy sources
Demographic problems and health of the population of Russia
Water resources of Russia
Soil resources of Russia
Forest resources of Russia
Energy and other types of resources of Russia
Particularly environmentally unfavorable territories of Russia
Destruction of ecosystems. desertification
Ecological lessons. Caspian and Aral Seas
Ecological problems of freshwater lakes
The concept of sustainable development
The concept of the noosphere in the modern sense
Ecological priorities of the modern world

1. Basic concepts (terms) of ecology. Consistency

The basic concept in ecology is "ecosystem". This term was introduced A. Tensley in 1935. An ecosystem is understood as any system consisting of living beings and their habitat, which are combined into a single functional whole.

The main properties of ecosystems are:the ability to carry out the circulation of substances, resistance to external influences, the production of biological products.

Usually, there are: microecosystems (for example, a small reservoir) that exist as long as they contain living organisms capable of cycling substances; meso-ecosystems (for example, a river); macroecosystems (for example, the ocean) as well as the global ecosystem - the biosphere

Larger ecosystems at the same time include ecosystems of a smaller rank.

Ecosystems (biogeocenoses) usually consist of two blocks. The first block, "biocenosis", includes interconnected organisms of different species, the second block, "biotope", or "ecotone", - habitat.

Each biocenosis includes many species, but represented not by individual individuals, but by populations, sometimes by their parts. A population is a separate part of a species that occupies a certain space and is capable of self-regulation, maintaining the optimal number of individuals of the species. In ecology, the term "community" is also often used. Its content is ambiguous. It is understood as a set of interconnected organisms of various species, as well as a similar set of only plant (plant community, phytocenosis), animal (zoocenosis) organisms or microbes (microbocenosis).

Consistency ecology lies in the fact that this science studies systems, their links and members, which are in close interdependence and interconnection. Therefore, many factors must be taken into account when considering various environmental phenomena and when planning any interventions in ecosystems.

There are three types of systems.

1. Isolated, not exchanging matter and energy with neighboring ones.

2. Closed, which exchange energy with neighboring ones, but not matter.

3. Open, exchanging matter and energy with neighboring ones. Most natural (ecological) systems are open.

The functioning of systems is impossible without links. They are divided into direct and reverse. Straight - a connection in which one element acts on another without a response (the effect of a tree layer of a forest on a herbaceous plant that has grown under its crown). Feedback - communication, where one element responds to the action of another.

2. Environment and environmental factors, their classification

Habitat - natural bodies and phenomena that are in direct and indirect relationships with the organism (organisms). The individual elements of the environment are factors.

1. Environment - an environment modified by man. The natural environment, the surrounding nature is an environment that has been changed to a small extent.

2. Or not modified by man.

3. Habitat - the living environment of an organism or species in which the entire cycle of its development takes place.

The influence of the environment on organisms is assessed through environmental factors (any element or environmental condition to which the organism reacts with adaptive reactions).

Classification of factors.

1. Factors of inanimate nature (abiotic): climatic, atmospheric, soil, etc.

2. Factors of living nature (biotic) - the influence of some organisms on others: from plants (phytogenic), animals (zoogenic), etc.

3. Factors of human activity (anthropogenic): direct impact on organisms (fishing) or indirect impact on habitat (environmental pollution).

Modern environmental problems and the growing interest in ecology are associated with the action of anthropogenic factors.

There is a classification of factors of the degree of adaptation of organisms to them according to the frequency (change of day, seasons, tidal phenomena, etc.) and the direction of action (climate warming, swamping of territories, etc.). Organisms most easily adapt to clearly changing factors (strictly periodic, directed). Adaptation to them is often hereditary. Even if the factor changes the frequency, the body continues to adapt to it for some time, to act in the rhythm of the biological clock (when changing time zones). Uncertain factors, such as anthropogenic factors, present the greatest difficulties for adaptation. Many of them act as harmful (pollutants). Of the rapidly changing factors, climate change (in particular, due to the greenhouse effect), changes in aquatic ecosystems (due to land reclamation, etc.) are of great concern today. In some cases, in relation to them, organisms use the mechanisms of pre-adaptation, i.e., adaptations developed in relation to other factors. For example, the resistance of plants to air pollution is to some extent facilitated by structures that slow down the processes of absorption of substances, which are also favorable for drought resistance, in particular the dense integumentary tissues of the leaves. This should be taken into account, for example, when selecting species for cultivation in areas with a high industrial load, as well as for urban greening.

3. Environments of life and adaptation of organisms to them

On Earth, one can conditionally distinguish four environments of life: soil, water, ground-air and the environment of organisms (when some organisms become a medium for others)

Environment-forming factors are those that determine the properties of environments.

Water environment. This environment is the most homogeneous among others. It almost does not change in space; there are no clear boundaries between ecosystems in it. The amplitudes of the factor values are also small. In particular, the temperature amplitudes do not exceed 50 °C (for the ground-air environment - up to 100 °C). The medium is characterized by high density (ocean waters - 1,3 g/cm3, fresh waters - close to unity). The pressure here varies with depth. The limiting factors are oxygen and light. The oxygen content is often not more than 1% by volume. There are few warm-blooded organisms in the water due to two reasons: a small temperature fluctuation and a lack of oxygen. The main adaptive mechanism of warm-blooded animals (whales, seals) is resistance to adverse temperatures. And their existence is also impossible without periodic communication with the air environment.

Most inhabitants of the aquatic environment have a variable body temperature (a group of poikilotherms). Organisms adapt to the high density of water, either using it as a support, or have a density (specific gravity) that differs little from the density of water (plankton group).

Ground-air environment. It is the most complex in terms of properties and diversity in space. Characteristic: low air density, significant temperature fluctuations, high mobility. Limiting factors - lack or excess of moisture and heat. For organisms of the ground-air environment, three mechanisms of adaptation to temperature changes are characteristic: physical (regulation of heat transfer), chemical (constant body temperature), and behavioral.

To regulate the water balance, organisms also use three mechanisms: morphological (body shape), physiological (release of water from fats, proteins and carbohydrates), through evaporation and excretory organs, behavioral (selection of the main location in space).

Soil environment. Its properties are close to the water and ground-air environments.

Many small organisms here are hydrobionts, they live in pore accumulations of free water. Temperature fluctuations are also small in soils. Their amplitudes decay with depth. The presence of pores filled with air is similar to the ground-air environment. Specific properties: dense addition (solid part or skeleton). Limiting factors: lack of heat, as well as lack or excess of moisture.

4. Biosphere as a global ecosystem

Concept "biosphere" introduced into scientific literature in 1875 by an Austrian geologist Eduard Suess He attributed to the biosphere all that space of the atmosphere, hydrosphere and lithosphere (the solid shell of the Earth), where living organisms meet.

Vladimir Ivanovich Vernadsky used this term and created a science with a similar name. In this case, the biosphere is understood as the entire space (the shell of the Earth) where life exists or has ever existed, i.e. where living organisms or products of their vital activity are found. V. I. Vernadsky not only concretized and outlined the boundaries of life in the biosphere, but, most importantly, he comprehensively revealed the role of living organisms in processes on a planetary scale. He showed that in nature there is no more powerful environment-forming force than living organisms and the products of their vital activity. V. I. Vernadsky deduced the primary transforming role of living organisms and the mechanisms of formation and destruction of geological structures, the circulation of substances, changes in solid (lithosphere), one (hydrosphere) and air (the atmosphere) of the Earth's shells. The part of the biosphere where living organisms are currently found is called the modern biosphere, (neobiosphere), the ancient biospheres are referred to (paleobiospheres). As an example of the latter, one can point to lifeless concentrations of organic substances (deposits of coal, oil, oil shale.), stocks of other compounds formed with the participation of living organisms (lime, chalk, ore formations).

The boundaries of the biosphere. The neobiosphere in the atmosphere is located approximately up to the ozone screen over most of the Earth's surface - 20-25 km. Almost the entire hydrosphere, even the deepest Mariana Trench of the Pacific Ocean (11 m), is occupied by life. Life also penetrates into the lithosphere, but for several meters, limited only to the soil layer, although it spreads hundreds of meters through individual cracks and caves. As a result, the boundaries of the biosphere are determined by the presence of living organisms or "traces" of their vital activity. Ecosystems are the main links of the biosphere. At the level of ecosystems, the main properties and patterns of functioning of organisms can be considered in more detail and deeply than is done on the example of the biosphere.

Through the preservation of elementary ecosystems, the main problem of our time is being solved - the prevention or neutralization of the adverse phenomena of the global crisis, the preservation of the biosphere as a whole.

5. Organization (structure) of ecosystems

In order for ecosystems to function for a long time and as a whole, they must have the properties of binding and releasing energy, the circulation of substances. The ecosystem must also have mechanisms to withstand external influences.

There are various models of ecosystems.

1. Block model of the ecosystem. Each ecosystem consists of 2 blocks: biocenosis and biotope.

Biogeocenosis, according to V. N. Sukachev, includes blocks and links. This term is generally applied to terrestrial systems. In biogeocenoses, the presence of a plant community (meadow, steppe, swamp) as the main link is mandatory. There are ecosystems without a plant link. For example, those that are formed on the basis of decaying organic remains, animal corpses. In them, only the presence of zoocenosis and microbiocenosis is sufficient.

Each biogeocenosis is an ecosystem, but not every ecosystem is a biogeocenosis.

Biogeocenoses and ecosystems differ in time factor. Any biogeocenosis is potentially immortal, since it always receives energy from the activity of plant photo- or chemosynthetic organisms. As well as ecosystems without a plant link, ending their existence, release all the energy contained in it in the process of decomposition of the substrate.

2. Species structure of ecosystems. It is understood as the number of species that form an ecosystem, and the ratio of their numbers. Species diversity is in the hundreds and tens of hundreds. It is the more significant, the richer the biotope of the ecosystem. Tropical forest ecosystems are the richest in species diversity. The richness of species also depends on the age of ecosystems. In mature ecosystems, one or 2–3 species of individuals that are clearly predominant in number are usually distinguished. Species that clearly predominate in the number of individuals are dominant (from Latin dom-inans - "dominant"). Also, in ecosystems, species are distinguished - edificators (from the Latin aedifica-tor - "builder"). These are the species that form the environment (spruce in a spruce forest, along with dominance, has high edificatory properties). Species diversity is an important property of ecosystems. Diversity provides a duplication of its sustainability. The species structure is used to assess the conditions of habitat for indicator plants (forest zone - acid, it indicates the conditions of moisture). Ecosystems are called by edificatory plants or dominants and indicator plants.

3. Trophic structure of ecosystems. Food chains. Each ecosystem includes several trophic (food) levels. The first is plants. The second is animals. The last one is microorganisms and fungi.

6. Stability and resilience of ecosystems

Concepts "stability" и "sustainability" in ecology are often considered as synonyms, and they are understood as the ability of ecosystems to maintain their own structure and functional properties under the influence of external factors.

It is more reasonable to distinguish between these terms, understanding sustainability as the ability of an ecosystem to return to its original (or close to that) state under the influence of factors that bring it out of balance. In addition, for a more complete characterization of the response of ecosystems to external factors, it is reasonable to use two more terms in addition to the above: "elasticity" и "plastic".

Elastic system one that is able to perceive significant impacts without significantly changing its structure and properties. But if the ecosystems given as an example are considered in terms of the above differences in sustainability and stability, then they will fall into different categories. Sustainability and stability are the parameters of ecosystems that often depend not so much on the structure of the communities themselves (their diversity), but on the biological and ecological characteristics of the edificatory species and dominants that form these communities. For example, high stability and significant resistance apply to pine forests on poor sandy soils, despite the low species diversity of such ecosystems. This is primarily due to the fact that the pine is very plastic and therefore it reacts to the transformation of conditions, in particular soil compaction, with a decrease in productivity and sometimes with the collapse of the ecosystem. But even in the latter case, due to the scarcity of the substrate in nutrients and moisture, its younger generation does not encounter serious competition from other species, and the ecosystem is very quickly restored again in the same form of edific climax. Other parameters of resistance and stability are typical, for example, for pine forests on rich soils, where they can be replaced by spruce forests, which have stronger edificatory properties. In them, despite the great diversity (species composition, layering, trophic structure, etc.), pine forest ecosystems are characterized by low stability and low resistance. Pine in this case acts as an intermediate link in the successional series. She manages to occupy and hold such habitats for some time only due to some unusual circumstances. For example, after fires, when strong competitors (spruce or deciduous tree species) are destroyed.

7. Agrocenoses and natural ecosystems

The main feature of ecosystems is ability of natural development and above all self-healing within 1 - 2 generations.

Can't be considered agrocenoses as an ecosystem or one of the stages (initial or intermediate) of a succession series. Agrocenoses of agricultural crops, in particular annuals, live only under the condition of continuous human intervention. With the termination of this intervention, secondary succession often begins from the stage, which is called weeds. But it is no longer related to agrocenosis.

In other words, agrocenosis is a community completely alien to natural conditions, therefore, it does not have the properties of an ecosystem. Other properties are inherent in agrocenoses created from long-lived forest plants. These works of man can be attributed to ecosystems, if not throughout their existence, then at certain stages of development. Although some properties of this ecosystem are not fully realized in comparison with natural communities. For example, this is found in a lack of stability, which can be explained by a lower diversity compared to natural communities. The second option is associated with habitats (more often - soils) that are characterized by significant wealth and nutrients, moisture. The creation of ecosystems bypassing the intermediate stages of succession will require long-term human intervention in their life until the selected species (spruce, pine, etc.) forms its own environment that prevents competitors (birch, willows, etc.). In most cases, the natural processes of ecosystem development win. The species that man introduces crowd out competitors so that they are not able to organize a full-fledged ecosystem, the one that man wanted to create. It is largely possible to eliminate the shortcomings of artificial ecosystems by creating multi-species communities, with the constant support of the species in which people are interested. As a result, human attempts to create immediately climatic communities, bypassing intermediate ones, are often doomed to failure for various reasons. This must be taken into account when solving specific economic problems. The above examples confirm how diverse are the connections in ecosystems, their dependence on abiotic, biotic and anthropogenic factors, as well as the obligatory nature of a systematic approach in any particular case. The possibilities of modeling and creating ecosystems by man largely depend on the biological properties of species, as well as on the conditions of habitat (habitat).

8. Dynamics and development of ecosystems. Successions

Ecosystems, adapting to changes in the external environment, are in a state of dynamics. This dynamics can apply both to individual links of ecosystems and to the system as a whole. Dynamics is associated with adaptations to external factors to factors that the ecosystem itself creates.

Daily type of dynamics associated with changes in photosynthesis and evaporation of water by plants, with the behavior of animals. Ecosystems change over the years as well. Periodically recurring dynamics - cyclic changes, or fluctuations, and directional dynamics - progressive, development of ecosystems.

succession - change of biocenoses and ecosystems in general.

1. primary succession - development takes place on a lifeless substrate (abandoned sand pits). Succession series end with relatively little changing ecosystems. They are called climax. The characteristic patterns of succession are that each has a set of species that are characteristic of a given region and are most adapted to a certain stage of development of the succession series. The final communities are also different. The species composition of climax communities can vary significantly. Common - ecosystems are united by the similarity of edificatory species.

Before a climax community (ecosystem) is formed, it is preceded by a number of intermediate stages. In the same area, several final ecosystems can form (polyclimax theory). For example, in the forest zone, meadow ecosystems are considered as climax ones. Proponents of the monoclimax theory (one community) believe that meadows in the forest zone exist for a long time only as a result of their use (mowing). When terminated, the existing ecosystem creates unfavorable conditions for the inhabitants. They will be replaced by forest communities. Succession changes are associated with the depletion of the soil and the extinction of organisms in it (soil fatigue). Together with natural factors, the cause of the dynamics of ecosystems is a person. They destroyed many indigenous ecosystems. Ecosystem changes, for example, include such types of human activities as the drainage of swamps, excessive deforestation, etc.

Anthropogenic impacts lead to simplification of ecosystems, digressions.

2. Secondary successions differ from the primary ones in that they do not start from zero values, but arise at the site of destroyed or disturbed ecosystems (after deforestation, fires). The main difference between these successions: - proceed faster than the primary ones, as they begin with intermediate stages (herbs, shrubs) against the background of richer soils.

9. Population structure

Populations are defined as relatively isolated parts of individual species within which interbreeding and transmission of information are more likely than between different populations of that species. An important factor in the isolation of populations within a species is the difference in habitat conditions. The same feature is at the basis of the selection of ecosystems. Usually, populations in which individuals of different ages are represented relatively evenly are distinguished by the greatest viability. Such populations are called normal. In the event that senile individuals prevail in the population, they are considered as regressive, or dying out. Populations represented mainly by young individuals are defined as invading or invasive. In the event that the population is normal or is in a state close to normal, a person can withdraw from it that number of individuals, or biomass (in relation to plant communities), which grows over the time interval between withdrawals. The amount of products withdrawn and the method of its withdrawal depends on the biological characteristics of the populations. For example, in animals leading a group lifestyle, it is impossible to reduce the number of groups to such a state that would entail the loss of their features of optimization of vital processes. For example, in relation to these tasks and in accordance with the ecological and biological properties of ecosystems (populations), foresters have developed various types of logging. First of all, they are divided into two large groups: the main и intermediate use.

During final felling, the entire forest stand that has reached the age of ripeness is removed. This type of farming is defined as soft management of natural processes. At the same time, in the vast forest tracts of the North, Siberia and other regions, so-called concentrated cuttings are often carried out over huge areas without taking into account the potential for restoration by their young generations of the forest. Such cuttings are carried out using heavy equipment, and are accompanied by a strong destruction and compaction of the forest soil cover. This then often leads to chain reactions of all natural processes, in particular, the existing water cycles here are replaced by the accumulation of stagnant waters on the soil surface, followed by the replacement of forest ecosystems with swamp ones. This type of farming is defined as hard intervention in natural processes. It should not have a place in the activities of modern man.

10. Dynamics of populations. homeostasis

Among the main properties of populations is dynamics the number of individuals characteristic of them and the mechanisms of regulation. Any significant deviation in the number of individuals of a species in populations is associated with negative consequences for its existence. In this regard, populations, as a rule, have adaptive mechanisms that contribute both to a decrease in abundance, if it significantly exceeds the optimal one, and to its restoration, if it decreases below normal values. For any population and species as a whole, the so-called biotic potential which is understood as the possible offspring from one pair of individuals in the exercise of the ability of organisms to biologically determined reproduction. The biotic potential is the higher, the lower the level of organization of organisms. It is used by organisms fully only in individual cases and for short periods. The conditions for this are created when organisms reproduce in environments that are rich in nutrients. This type of population growth is called exponential. A type of growth close to exponential is characteristic of the human population in our time. It is determined by a significant decrease in mortality in childhood. Periods of sharp changes in population are called "population waves", "waves of abundance". Large changes in abundance compared to average values mainly have negative consequences for the life of the population (for example, high abundance - the weakening of all individuals due to lack of food).

Distinguish population dynamics independent from the number of its individuals and dependent. The first type is characterized by an exponential growth curve. For the second - logistic. In the population-independent type, the dynamics is determined mainly by abiotic factors, while the density-dependent population dynamics is determined by biotic factors. The larger the number, the stronger the mechanisms that cause its decrease. Competition is also at the basis of intra-population homeostasis. It can manifest itself in hard and soft forms. Softened forms appear more often through the weakening of some individuals. With a high density of individuals in populations, stress phenomena can be a regulating factor in abundance.

Migrations as a factor of homeostasis, they manifest themselves mainly in two forms. The first is a mass exodus of individuals from the population during overpopulation phenomena (especially characteristic of lemmings, squirrels). The second type of migration is associated with the gradual (calm) departure of some of the individuals to other populations.

11. Social and applied ecology

Social and Applied Ecology considers and analyzes issues and problems related to human activity, especially since the period when man began to act as a powerful geological force (according to V. I. Vernadsky). This period is associated mainly with the industrial revolution and in particular with the last 20 years of scientific, technological and information revolutions. Since that time, the term "ecology" has become widely used and focused on man and his environment. If general ecology focuses on factors, their action in natural ecosystems, then social and applied ecology considers mainly anthropogenic factors, the specifics of their action in natural, natural-anthropogenic, social systems. The tasks of social and applied ecology are not limited to stating changes in the world around, which a person voluntarily or involuntarily introduces into it. It is also engaged in the search for scientifically based ways and methods of preventing changes, their neutralization. It is also important to evaluate technical, economic, organizational moral and other means, approaches to solving environmental problems. In the modern world, it is necessary to search for new, often unconventional ways to solve environmental problems and the survival of mankind. This is possible only through a person's coordination of his activity with the possibilities of nature in two directions: technological - the development of new and improvement of existing technologies in accordance with environmental laws and rules; social - through a more rational use of products. The effectiveness of solving social ecology issues directly depends on the extent to which the applied methods are consistent with the laws of general ecology. As a result, the contradictions between man and the environment cannot be removed without deep and versatile environmental knowledge, serious economic costs. Compensation costs increase from year to year, and the range of issues analyzed in social ecology is expanding. They can be combined into three sections: the peculiarity of man as a biosocial species, his place in ecosystems, the scale of his impact on the environment; problems caused by human activities, their content, causes and consequences; modern and predictable ways and means of solving environmental problems.

This section of ecology is closely connected both with general ecology and with a complex of social (culture, sociology, economics), natural (biology, geography) and applied (nature management, energy) sciences.

12. Concepts and terms used in social and applied ecology

Social and applied ecology studies human-modified ecosystems (natural-anthropogenic) or artificially created objects: agrocenoses, settlements, cities, industrial complexes, etc. Concepts that refer to natural objects that surpass the rank of elementary ecosystems are widely used. They are often distinguished within the boundaries of geographical areas. These include natural zones (tundra, forest, etc.) and their elements (watersheds, river terraces, etc.). If various natural components naturally combine in the system, it is considered as a landscape, or a natural-territorial complex (NTC). These concepts are large ecosystems identified according to established geographical criteria.

Objects are isolated on the basis of matter and energy flows.

There are four types of ecosystems:

1) transit, within which the unidirectional flow of matter prevails

2) eluvial (removal), the removal of substances from which prevails over the inflow;

3) transit, the supply and removal of matter and energy in which are approximately balanced. These are most often the slopes of the relief, flowing waters, etc.;

4) accumulative (accumulative), which are characterized by the predominance of the input of matter over its removal. Systems of this type include lowered relief elements (inland water bodies, swamps, seas, oceans). Systems that combine signs of various types are distinguished as intermediate (transit-accumulative, eluvial-accumulative, etc.). Biogeochemical provinces and watersheds are usually distinguished. Biogeochemical provinces characterize the chemical composition and the geological rocks that form them (granites, sandstones, limestones, etc.) or the circulation of substances. In particular, provinces are distinguished with an increased or insufficient content of iodine, calcium, copper, magnesium, sulfur, chlorides, soda, etc. An excess of toxic elements or a lack of biophilic elements often cause a violation of the physiological functions of organisms, lead to low productivity and diseases, such like dwarf growth, rickets, goiter, etc. Biogeochemical provinces have clear boundaries, and they are characterized by all the features of ecosystems. Drainage basins are understood as areas from which water flows into certain bodies of water. These are systems with clear boundaries, which are introduced according to the nature of the relief. In them, the factors that determine the processes are water and the substances carried by it.

In them, the environmental consequences of human activity are studied through monitoring the quality of water in certain parts of watersheds.

13. Regulations (laws, rules, principles) used in social and applied ecology

Provisions general ecology are also important for human-oriented ecology, some of them are borrowed from other sciences (physics, chemistry), some others are formulated by ecologists (V. I. Vernadsky, B. Commoner, N. F. Reimers).

1. The principle of a holistic consideration of phenomena, or holism. Two main approaches to the analysis of phenomena: reductionist and holistic. The reductionist approach is used to solve problems with clearly defined parameters. Holistic is the basis in the study of natural phenomena with numerous connections and interdependencies.

2. The principle of natural chain reactions. It refers to a number of natural phenomena, each of which leads to a change in other phenomena. Chain reactions can be caused by various interventions in ecosystems. Their probability increases under the influence of anthropogenic factors. Any harsh intervention in natural processes is accompanied by chain reactions.

3. Law of internal dynamic balance. Chain reactions are the result of violation of the law of internal dynamic equilibrium. The energy, information and dynamic qualities of some natural systems and their hierarchy are interconnected so that any change in one of the indicators causes changes in others (according to B. Commoner, "everything is connected with everything").

4. The law of reducing the energy efficiency of nature management. The more the system is removed from the state of ecological equilibrium, the more energy costs are required for its restoration.

5. The principle of incomplete information about ecosystems. According to him, our knowledge of ecosystems is always insufficient. This is explained by the multicomponent nature of ecosystems, the dynamics of processes, a large number of connections and interdependencies, etc. As a result, each ecosystem is individual. And also the principle of analogies is practically inapplicable to ecosystems.

6. Rule of ten percent. It is extended to nature management from general ecology. With regard to nature management: more than 10% of a renewable resource cannot be withdrawn from ecosystems at a time.

7. The principle of optimality. Any system with the greatest efficiency functions within certain spatio-temporal limits.

8. The principle of accumulation of pollutants in food chains.

9. The principle of self-purification of ecosystems. Ecosystems and their environment are capable of self-purification. This ability is characterized through the decomposition potential.

10. The concept of maximum permissible concentrations (MPC) of environmental pollution. MPC - the amount of pollutant that does not have a negative impact on a person and his offspring.

14. Man's place in biospheric processes

The main impact of man on the environment is associated with his tool activity, power supply, with the ability to accumulate, store and transmit information to generations. Degree of agreed human activity with the laws and principles of general ecology is determined by the following factors.

1. Changing the boundaries of optimal and limiting factors. A person is able to change the strength of action and the number of limiting factors and expand or narrow the boundaries of the average values of environmental factors.

2. Changes in population regulation factors. Man removed or partially destroyed almost all natural mechanisms of population homeostasis in relation to his population. Abiotic factors practically do not affect its abundance.

3. Impact on the existence of ecosystems. Individual ecosystems and their large blocks (for example, steppes) have been almost completely destroyed by man. In others, he significantly violates their inherent processes, principles and patterns of development (food chains, changing the boundaries of ecological niches, impact on ecosystem dynamics).

4. Human influence on the functions of living matter in the biosphere. One of the major results of human activity was the violation of the mechanisms of functioning of living matter and its functions. Here are some of them:

1) the constancy of living matter;

2) transport and scattering functions of living matter;

3) destructive and concentration functions. Strengthening by man of destructive (destructive) phenomena in the biosphere (thousands of times in comparison with natural processes) occurs as a result of the extraction of resources from the bowels, the use of the surface of the lithosphere.

5. Consequence of differences in the rates of social and technological progress. The social component has now become decisive in human activity, its influence on the environment. Social and related technogenic structures are characterized by low environmental efficiency. Only 2-3% of the product needed by a person is extracted from the resources. Such phenomena are largely explained by the discrepancy between the rates of development of technical and social structures, the advance of the former by the latter.

6. Change in the time factor in the development of biospheric processes. The time of development of the biosphere associated with human activity is considered as noogenesis. It was preceded by the time of biogenesis. These periods cannot be compared either in duration or intensity of the modification of biospheric processes.

7. Alienation of man from nature. Human actions are characterized both by a violation of the time factor in the development of biospheric processes, and by alienation from nature, subordinating it to their goals.

15. Cycles of substances and their violation by man

There are two types of cycles of matter: large (between land and ocean), and small (within ecosystems). Small cycles are more often disturbed as a result of a discrepancy between the mass of substances supplied to the environment and the potentials of organisms for their decomposition.

The carbon cycle. The carbon contained in the atmosphere in the process of photosynthesis is introduced into the organic matter of plants, and then into the food chain. The release of carbon from organic matter occurs in the process of respiration of organisms. A large mass of carbon is released from dead organic matter by decomposer organisms. The disruption of carbon cycles is associated with its release from geological structures and as a result of changes in the area and productivity of plant communities, etc. Part of the carbon accumulates in the atmosphere in the form of carbon dioxide and methane, creating a greenhouse effect.

The nitrogen cycle. The main source of this element is the atmosphere, from where nitrogen enters the soil and then enters plant organisms only as a result of its conversion into an assimilable compound - nitrates. The latter are formed as a result of the activity of nitrogen-fixing organisms. These include certain types of bacteria, blue-green algae and fungi. A large proportion of nitrogen entering the ocean is used by aquatic photosynthetic organisms, enters the food chains of animals, returns to land with products of marine fishery, birds fertilizers) and unintentionally (high temperatures, e.g. generated by internal combustion engines). The negative consequences of the violation of the nitrogen cycle are manifested through pollution with oxides, ammonia, other compounds of atmospheric air and water, and the accumulation of nitrates in food products.

Sulfur cycle. Sulfur is one of the most aggressive and common environmental pollutants. Violations of the sulfur cycle are associated with the combustion of organic matter, the processing of sulfur-containing ores. Sulfur enters the atmosphere in the form of toxic compounds, dioxides.

Phosphorus cycle. After repeated consumption of phosphorus by organisms on land and in the aquatic environment, it is excreted in bottom sediments. The return of phosphorus with the organisms of the ocean does not compensate for its needs on land. A negative consequence of the violation of the phosphorus cycle is its entry into aquatic ecosystems with mineral fertilizers and synthetic detergents.

16. Environmental crises and environmental situations

Man and other creatures live in an environment that is the result of anthropogenic factors. It is different from the environment that is considered in general ecology. Man's visible change in the environment began from the time when he moved from gathering to more active activities: hunting, domesticating animals and growing plants. Since that time, the principle of "ecological boomerang" began to work: any action on nature that nature could not perceive returned to man as a negative factor. Man began to separate himself more and more from nature and enclose himself in a shell of an environment formed by himself. Since the modern environment and the ecological situation are the result of the action of anthropogenic factors, several specific features of the action of the latter can be distinguished: irregularity of action and unpredictability for organisms, high intensity of changes, almost unlimited possibilities of action on organisms up to their complete destruction, natural disasters, cataclysms. Human influences can be both purposeful and unintentional.

Crisis - one of the negative states of the environment, nature or biosphere. It is preceded or followed by other states, ecological situations Ecological crisis - changes in the biosphere or its parts over a large area, which are accompanied by a change in the environment and systems as a whole and a transition to a new quality. The biosphere has repeatedly experienced acute crisis times due to natural phenomena (for example, at the end of the Cretaceous period, five orders of reptiles died out in a short period of time - dinosaurs, pterosaurs, ichthyosaurs, etc.).

Crisis phenomena have been repeatedly generated by climate change, glaciation or desertification. Human activity repeatedly contradicted nature, giving rise to crises of various scales. But due to the small population, poor technical equipment, they never took on a global scale.

For example, Sahara 5 - 11 thousand years ago was a savannah with rich vegetation, a system of large rivers. The destruction of the ecosystems of this region is explained, on the one hand, by excessive pressure on nature, and, on the other hand, by climate change (desiccation).

The Romans, after the conquest of North Africa, brought its lands to a critical state by predatory plowing and grazing of huge herds of horses used for military purposes.

Common to all anthropogenic crises is that the way out of them is accompanied by a decrease in the population, its migration, and social upheavals.

17. Human environment and its components

In the environment that surrounds a person, there are four components.

1. Direct natural environment ("first nature", N. F. Reimers), or slightly modified by man, or modified to such an extent that it has not yet lost its basic properties - self-healing, self-regulation). The natural environment itself is very close to that which is called "ecological space". Now such a space is about 1/3 of the land. However, these are mainly territories with harsh conditions that are not suitable for human life (wetlands of the north, high mountain regions, glaciers, etc.), which are located in Antarctica, North America (Canada), Russia, Australia and Oceania and some other areas .

2. Natural environment transformed by people ("second nature"), otherwise the environment is quasi-natural (from Latin quasi - "as if"). She is incapable of self-maintenance for a long time. These are various types of "cultural landscapes" (pastures, gardens, arable land, vineyards, parks, etc.).

3. Man-made environment ("third nature"), artenatural environment (from Latin arte - "artificial"). It includes residential premises, industrial complexes, urban developments, etc. This environment can only exist if it is constantly maintained by a person. Otherwise, it is inevitably doomed to destruction. Within its boundaries, the cycles of substances are sharply disturbed. This environment is characterized by the accumulation of waste and pollution.

4. Social environment. It has a great influence on a person. This environment includes relationships between people, the degree of material security, the psychological climate, health care, general cultural values, etc. "Pollution" of the social environment with which a person is in continuous contact is also dangerous for people, even more than environmental pollution natural. The social environment can act as a limiting factor, preventing others from showing up. However, it should be taken into account that the social environment is mediated by other environments, and vice versa.

As civilization develops, man isolates himself more and more from the natural environment. Large expenditures are required for the preservation of the natural environment itself, as well as for the maintenance of the second, third environments, which are not capable of self-regulation. Low-waste production, closed cycles, treatment facilities, etc. will not be able to solve the problem of optimizing the relationship between man and the environment, if a set of issues that relate to the protection of the first nature and the improvement of the social environment are not resolved

18. Modern ecological crisis and its features. The scale of human impact on the environment and the biosphere

The main feature of the current ecological crisis is its global nature. It is spreading and threatening to cover the entire planet. In this regard, the usual methods of overcoming crises by resettlement to new territories are not feasible. Modification of production methods, norms and volumes of consumption of natural resources remains ideal. The latter has now reached grandiose proportions. Man has approached the maximum allowable limits for the withdrawal of water from rivers (about 10% of the runoff). In general, a person today involves in the production and consumption of such an amount of matter and energy that is hundreds of times greater than his biological needs. The consumption of resources and energy for industrial purposes is much greater. About 300 million tons of matter and materials are mined and processed daily, 30 million tons of fuel are burned, and they are withdrawn from rivers, sources of about 2 billion m3 of water, more than 65 billion m3 of oxygen.

Man has almost completely destroyed some landscapes within natural zones. Almost completely disappeared, for example, such large ecosystems as steppes. There are also few virgin forests left: 2/3 of their area has been destroyed, and the rest, to a greater or lesser extent, bear traces of human activity. The area occupied by forests has now decreased from 75 to 25%. The complexity of the current environmental situation is also due to the fact that humanity is not able to abandon the achievements of technological progress and the use of natural resources. With the rapidly increasing technical equipment and the explosive growth of the world population, the influence of man on the environment is increasing. Rejected plans to divert water from northern rivers to the southern regions of the former Soviet Union are currently being considered. They provided for the movement of about 150 km3 of water per year (more than half of the annual flow of the Volga River). Even larger water redistribution projects exist in other countries. For example, one of them provides for the transfer of water of about 100-300 km3/year from the northern rivers of Canada to the USA and Mexico. At the same time, the implementation of this project will require the construction of dams up to 500 m high. With the help of such measures, it is planned to increase the area of irrigated land in the United States by 70%, and in Canada by 15%. There is a project to flood the Sahara by building a dam in the lower reaches of the Congo River and turning its flow back. One of the projects involves the delivery of 200 billion m3 of water in the form of icebergs from Antarctica.

19. Basic concepts of demography (2)

Demography (from the Greek demos - "people", grapho - "I write") is a science that studies the population, in particular its structure, dynamics and reproduction (birth rate, life expectancy, mortality), composition in their connection with socio-historical development .

In recent years, a new direction in demography has been created - demography ecological, or socio-ecological demography, which studies the relationship between demographic processes and the human environment.

The following generally accepted concepts and terms are widely used in ecological demography.

1. The total fertility rate (CFR) is the average number of children born per year per one thousand people in the population.

2. The average fertility rate (TFR) is the average number of children a woman has in her lifetime. In China, government policy has long focused on birth control. As a result, the average birth rate here has decreased from 4 5 in the 1970s. to 2,6 in the 1980s and up to 2,4 - 2,3 - in modern times. Measures to limit the birth rate are also carried out in some other countries, but they are not always sufficiently effective.

3. Crude mortality rate (CDR) is the average number of people who die per year per one thousand people of the population.

4. Natural population growth - shows the difference between TFR and RAC. In order to show the natural increase as a percentage, its value should be divided by 10.

5. Demographic transition - this concept characterizes the period of population growth in a particular country or in the world, which is due to high birth rates while significantly reducing mortality, especially child mortality.

6. Demographic potential is an indicator of population growth, not taking into account the reduction in the birth rate to the level of simple reproducibility.

7. A population explosion is a sharp increase in population growth, which, as a rule, is due to an intensive decrease in mortality, especially among children, while maintaining a high birth rate. The human population today is characterized by an unprecedented demographic explosion. It is mainly clearly expressed in the countries of Asia, Latin America, Africa, which belong to the group of developing countries. They are also called the countries of the poor South.

20. Features of the demography of developed and developing countries

population growth observed in recent decades. If it took more than 2 million years to reach the first billion of the population, then the growth of each subsequent billion required less and less time: the second - 100 years, the third - 30, the fourth - 15, and the fifth - only 12 years.

The production of industrial and food products, the extraction of natural resources, energy, the accumulation and storage of information are also growing. This indicates a close relationship between population size, scientific and technological progress, and human impacts on the environment. In the 1970s - 1980s. the world population has increased by 2,0 - 2,2% per year. In recent years, this indicator has decreased to 1% But due to the increased population, its absolute increase now clearly exceeds the values that were available at growth rates of 7% or more. At present, it is about 2 million people per year. Moreover, the growth, as well as the population, is mainly in developing countries. Approximately 90 billion people live in them, and the average increase is about 3,9% (OKR - 2,1, OKS - 31), or 10 million people per year. For comparison: about 83 billion people live in developed countries, and the average increase is 1,2 0% (OCR - 6 OCS - 15) or 9 billion people / year.

Population growth is sometimes estimated by its doubling time. In developing countries, doubling occurs in 33 years, while in developed countries it takes only 117 years. Zero population growth occurs with simple reproducibility (when a family has two parents and two children). In fact, taking into account child mortality, now the simple reproduction of the population provides TFR, which is equal to 2,20 in developing countries and 2,03 in developed countries. In reality, in developed countries the TFR is about 2, and in developing countries it is about 4. In a number of developed countries, the growth has completely stopped or has negative values. The population is decreasing in countries such as England, Germany, Denmark, Russia, Hungary. On average, in Europe, population growth is currently no more than 0,23%. Here is also the most unfavorable age composition of the population for increasing the number. In addition to mortality and fertility, population changes in certain regions and countries occur due to emigration or immigration. In the United States, in particular, a 1/3 increase in the population is due to immigration. That's not even counting illegal immigrants.

21. Demographic pyramids and population forecast

For forecast population in the future, its age composition is of great importance. The latter is usually represented graphically as pyramids

For developed countries, a columnar pyramid is characteristic. A small proportion of the younger generation indicates a general aging of the population and the lack of prospects for population growth. The age pyramid for developing countries expands strongly downwards with a large proportion of the generation that is in childbearing age or younger. From which it follows that the population explosion continues, and the gap in the population of developed and developing countries will increase.

The increase in the world population is not unlimited. It is assumed that its stabilization will begin after the population reaches 10-12 billion people.

Economist Thomas Malthus assumed that humanity would meet with crises as a result of food shortages. To reduce the rate of population growth, T. Malthus proposed to legalize late marriages. But the achievements of science and practice today, the great opportunities for increasing yields, indicate that food shortages will not become a limiting factor in population growth in the coming decades. At present, humanity is not facing the problem of hunger, but the limited resources of the environment and its pollution. But this does not exclude the possibility of regulating the birth rate by legislative acts and other individual measures.

There are the following theories of a way out of the current demographic situation.

1. Demographic maximalism - the larger the country's population, the better. In the 1950s - 1960s, this concept was embodied in China.

2. Demographic utopianism - a way out will be found, for example, through the settlement of space, the World Ocean, etc.

3. Demographic finalism - population growth will lead to the depletion of resources and environmental pollution, the problem will be solved through the death of part of humanity.

4. Demographic fatalism - problems will be solved by themselves thanks to the mechanisms of biological self-regulation.

The above concepts are based on biological criteria and do not take into account the social patterns of the development of society, in connection with which the population explosion is limited in time. Purposeful regulation of the human population occurs mainly through changes in the birth rate, often at the level of public policy.

22. The concept of "natural resources", their classification. Problems of exhaustibility of natural resources

Natural resources - natural objects used by man and contributing to the creation of material wealth. Natural conditions affect human life and activity, but do not participate in material production (air until a certain time was only a natural condition, now it is both a condition and a resource).

Resource classifications. In addition to natural resources, there are material resources (vehicles, industrial facilities, buildings), labor resources. Among the signs of natural resources, there are: atmospheric aquatic plants. There is also a classification of natural resources according to their exhaustibility: animals, soil, bowels, energy. Exhaustible resources are those that can be exhausted in the near or long term. These are subsoil and wildlife resources. Usually, a resource is considered exhausted when its extraction and use (including processing) becomes economically unprofitable. The latter depends on the level of technology (for example, oil, coal). In other cases, the use of the resource is cost-effective until it is completely exhausted. In particular, the extermination of certain species of animals and plants. Inexhaustible resources are resources that can be used indefinitely. These are the resources of solar energy, marine wind tides. Water has a special position among the resources. It is exhaustible due to pollution (qualitatively), but quantitatively inexhaustible. The problem of the exhaustibility of natural resources becomes more urgent every year. The growth rate of resource consumption is an order of magnitude higher than the population growth rate. Every year, as many fossil fuels are burned as nature accumulated them over millions of years. According to one of the forecasts, if such rates of growth in the use of fossil fuels continue, then oil reserves will last for about 30-40 years, gas - 40-45 years, coal - 70-80 years. Potassium salts and phosphates will be exhausted after 2100, manganese ore - by 2090. Iron and aluminum remain the most promising metals. Iron in terms of consumption currently occupies the first place and the second in terms of distribution in the earth's crust (after aluminum). The difficulties of its use are due to the fact that its bulk is contained in compounds with a small amount. Iron smelting is associated with atmospheric pollution by harmful compounds such as sulfur dioxide and carbon dioxide. Aluminum smelting is associated with a significant energy intensity of production. In particular, in the United States, about 3% of the energy produced in the country is spent on obtaining aluminum.

23. Resource use and pollution problems

Under environmental pollution understand the introduction of unusual substances into it or an increase in the concentration of existing ones (chemical, physical, biological) above the natural level, leading to negative consequences. A pollutant can be either a toxic or harmless substance or a substance necessary for organisms, the content of which will go beyond the optimal concentration values. In particular, high-quality natural water, but in excess, can act as a pollutant, for example, when soils are over-irrigated.

Pollution is often defined as any natural resource or element that is misplaced.

Pollution is classified according to various parameters.

1. By origin: natural and artificial.

2. According to sources: industrial, agricultural, transport, point (pipe of an enterprise), object (enterprise), scattered (agricultural field, ecosystem), transgressive (spread from other regions).

3. By the scale of impact: global, regional, local; by elements of the environment: atmosphere, hydrosphere, soil.

4. By place of action: rural environment, urban environment within industrial enterprises, etc.

5. By the nature of the action: chemical, physical, thermal, electromagnetic noise.

6. According to the frequency of action: primary, secondary; according to the degree of resistance: stable, resistant, unstable

The level of persistence of pollutants depends on their ability to be decomposed by various agents or move to another environment where they will not be a pollutant. The more persistent the pollutant is, the more pronounced its cumulative effect in the environment.

Pollution parameters.

1. By the volume of receipts on Wednesday.

2. By aggressiveness (poisonousness).

3. According to the degree of pollution.

Of the extracted resources, only 2 - 3% is used as a useful product, and the rest are waste (waste rock, slag, etc.). A useful product is often an unfavorable environmental pollutant, as it is treated with various substances (antiseptics, coatings) against destruction by biological agents. When such items are removed from use, they often become long-lasting contaminants in the environment. Also dangerous are the results of human activity on the removal of substances unusual for it and alien to living organisms (xenobiotics) into the natural environment. In nature, there are about 2 thousand inorganic and about 2 million organic compounds. Man has learned to synthesize more than 8 million compounds. Every year their number increases by several thousand. About 50 thousand such substances enter the biosphere

24. The main properties of the atmosphere and human impact on it

Atmosphere is a complex system that consists of air, water vapor and chemical impurities. This is an important factor in the meteorological regime and a condition for physicochemical and biological processes in the biosphere. The balance of individual components in the atmosphere determines its effect on thermal, water, radiation regimes, and the ability to self-purify. The gas composition of the atmosphere, water vapor, various suspensions contained in it determine the degree of radiation of solar radiation to the Earth's surface and the conservation of heat in near-Earth space. If the atmosphere did not contain impurities, the average annual temperature of the Earth's surface would be 18 C. Important properties atmosphere are its ability to rapidly mix and move over vast distances, communication with other areas, especially with the ocean. These qualities, as well as the absence of a pronounced cumulative effect of pollutants, determine the global nature of atmospheric processes, as well as its high ability to self-purify. Thus, the ocean absorbs large masses of carbon dioxide and monoxide, sulfur dioxide, and other compounds from the atmosphere. A significant amount of atmospheric impurities is absorbed by plants. Man has an impact on various properties of the atmosphere: thermal regime, chemical composition, movement, radioactivity, electromagnetic background, etc. Man's noticeable impact on the atmosphere began from the time when he began to actively interfere in biospheric processes, destroy forests, burn them out, plow land and drain it, build cities, etc. The most dangerous are human impacts on the atmosphere, which have acquired global significance. Carbon dioxide occupies the first place in terms of emissions into the atmosphere. High chemical aggressiveness combined with high stability with significant emissions (150-200 million tons/year) is also characteristic of sulfur dioxide (SO2), sulfur dioxide. It is a colorless gas with a pungent odor. The products of its compounds with water (sulfuric and sulphurous acids) cause damage to the respiratory tract in animals and humans. Other harmful sulfur compounds also enter the atmosphere. These include hydrogen sulfide (H2S), a highly toxic, colorless gas with a rotten egg odor. Even in the initial stages of poisoning with it, a person loses his sense of smell, large doses of poisoning lead to pulmonary edema, respiratory paralysis, and death. Sulfur and its compounds enter the atmosphere from both natural and anthropogenic sources. A large influx of anthropogenic sulfur into the atmosphere occurs when fuel is burned.

25. The problem of the greenhouse effect

Greenhouse effect - possible increase in global temperature on Earth as a result of changes in the heat balance of greenhouse gases.

B. Nebel sees the greenhouse effect as the greatest catastrophe to come. A similar catastrophe occurred about 60 million years ago, which led to the extinction of entire groups of animals and plants. The main greenhouse gas is carbon dioxide (50-65%). Also, greenhouse gases include methane (20%), nitrogen oxides (5%), ozone, freons and other gases (10-25% of the greenhouse effect). In total, about 30 greenhouse gases are emitted. The warming effect depends not only on the amount of greenhouse gases in the atmosphere, but also on their relative activity per molecule. Greenhouse gases are a significant obstacle to the escape of heat rays into outer space. They, as it were, fall into a trap and thereby increase the air temperature. Due to greenhouse gases, the average annual air temperature over the past century has increased by 0,3 - 0,6 °C. It is predicted that as a result of climate warming, eternal snow and ice will begin to melt and the ocean level will rise by about 1,5 m. The release of a mass of water accumulated in glaciers will be able to raise the ocean level by 60-70 m. sea level rise is seen as an environmental threat of unparalleled proportions. It is predicted that with an increase in the ocean level by 1,5 - 2 m, about 5 million km2 of land will be flooded. In addition, climate warming will be accompanied by an increase in the degree of weather instability, an increase in the number of hurricanes and storms, a shift in the boundaries of natural zones, and an acceleration in the rate of extinction of animals and plants. At the International Conference on Climate Change in Toronto in 1979, the opinion was expressed "that the final consequences of the greenhouse effect can only be compared with a global nuclear war." Along with technogenic processes, ecosystems themselves are becoming more and more significant suppliers of greenhouse gases, in which a person violates the formed cycles that release carbon dioxide, methane and other gases.

There are factors that act in the opposite direction of the greenhouse effect. Increasing dustiness prevents solar radiation and its thermal component from reaching the earth's surface. The extreme manifestation of the inverse greenhouse effect is nuclear winter, or the nuclear night of the planet, due to a sharp increase in the dustiness of the atmosphere.

26. Ozone problem

The problem of ozone in the atmosphere is two aspects: its destruction in the upper layers (ozone screen) and an increase in concentration in near-Earth space.

The ozone screen is located at the poles at an altitude of 9-30 km, at the equator - at 18-32 km. The concentration of ozone in it is about 0,01 - 0,06 mg/m3. Its layer is approximately 3 - 5 mm. Ozone in the upper atmosphere is formed when an oxygen molecule (O2) breaks down into two oxygen atoms under the action of ultraviolet rays. The condition for the occurrence of this reaction is the presence of ultraviolet rays and their conversion into infrared thermal. Ozone absorbs rays with a wavelength of 200-320 nm. Some of them reach the Earth. Recently, there has been a trend towards a decrease in the ozone content in the upper atmosphere. In the middle and high latitudes of the northern hemisphere, it was about 3%. Reducing the ozone content by 1% will lead to an increase in the incidence of skin cancer by 5 - 7%. The most significant loss of ozone is recorded over Antarctica. Here, its content has decreased by 30-40% over the past 50 years. The space within which a decrease in ozone concentration is recorded is called "the ozone hole". The size of the ozone-depleted hole is growing at about 4% per year. At present, it is larger than the area of the United States. A slightly smaller hole over the Arctic. Wandering holes with an area of 10 to 100 thousand km2 appear in other zones, where ozone losses reach 20-40% of the usual level.

Causes The appearance of ozone holes is not fully understood. They were first discovered in the early 1980s.

Freons (freons) are currently considered the main anthropogenic factor that destroys ozone. In a number of countries (USA, Great Britain, France), freons are replaced by hydrochlorofluorocarbons.

Other ways to increase the stability of the ozone layer are also being sought. For example, the formation and accumulation of ozone is facilitated by electromagnetic radiation, laser beams. They stimulate the photodissociation of oxygen, promote the formation and accumulation of ozone.

Intensively the ozone layer is destroyed in the spring. Low temperatures, increased cloudiness in winter contribute to the release of chlorine from freons, and chlorine acts on ozone more intensely when the temperature rises slightly. Now scientists have begun to speak out that there is not enough evidence that the appearance of ozone holes is the result of human activity. Similar phenomena occurred before and are explained exclusively by natural processes, for example, 11-year cycles of solar activity.

27. Acid rain problem

Sulfur dioxide - a pollutant that causes the appearance of acid precipitation. Combining with water vapor, sulfur dioxide turns into a solution of sulfuric acid. Nitric and carbonic acids are also formed from carbon dioxide and nitrogen oxides. Together with organic acids and other compounds, they form a solution with an acidic reaction (acid precipitation)

The proportion of SO in acid precipitation is approximately 70%. 20-30% of acid precipitation is other emissions. CO2 also contributes to the formation of acid precipitation. Due to its constant presence in the atmosphere, the normal pH of precipitation is 5,6.

They were first registered in 1907-1908. in England. To date, there have been cases of precipitation with acidity close to lemon juice or household vinegar.

Acid precipitation is most common in the northern hemisphere, since there are significant emissions of acidic substances and favorable conditions for their deposition in the form of rain, snow, and fog. Long periods of low temperatures increase the duration of acid precipitation. The latter are largely neutralized by ammonia, and in winter its release from soils, organic matter, and other sources is very insignificant due to the inaction of ammonia-forming microorganisms.

Acid precipitation is typical for the Scandinavian countries, England, Germany, Belgium, Poland, Canada, northern regions of the USA. In Russia, areas of acid precipitation formation: the Kola Peninsula, Norilsk, Krasnoyarsk and other areas. Today in St. Petersburg the pH of rain is from 4,8 to 3,7, in Kazan it is from 4,8 to 3,3. In cities, up to 70-90% of air pollution, including for the formation of acid precipitation, is supplied by vehicles.

The negative impact of acid precipitation is very diverse. They affect soils, aquatic ecosystems, architectural monuments, buildings and other objects.

Acid precipitation has a tangible negative impact on soils in both northern and tropical regions. This is due to the fact that podzolic soils are acidified. These soils do not contain natural compounds that neutralize acidity (calcium carbonate, dolomite, etc.).

Tropical soils, although often neutral and alkaline, also do not contain acid neutralizing substances due to intense and constant washing by heavy rains. Getting into the soil, acid precipitation significantly increases the mobility and leaching of cations, reduces the activity of decomposers, nitrogen fixers and some other organisms in the soil environment.

28. Water as a substance, resource and condition of life

All the waters of the Earth are one. They, together with the atmosphere and lithosphere, are an independent sphere - hydrosphere, which is characterized by distinctive features. It is she who acts as an independent environment of life (along with the ground-air, organismic, soil). At the same time, it permeates other spheres (atmosphere, lithosphere) and life environments.

Water - an indispensable condition and factor of life, and in fact it is affected by a person on a large scale.

Significant attention is paid to the causes, environmental consequences and potential solutions to environmental problems.

The main unique properties of water, which determine its influence on the most important processes in the biosphere, are as follows.

1. Inexhaustibility as a natural resource and as a substance; all other natural resources are destroyed or dispersed.

2. Only water is characterized by expansion during solidification (freezing) and a decrease in volume during the transition to a liquid state.

3. The highest density at a temperature of +4 ° C and the associated very important properties for natural and biological processes, in particular, the exclusion of deep freezing of water bodies.

4. High heat capacity and significant thermal conductivity.

5. The ability to very easily pass into a gaseous state both at positive and negative temperatures.

6. Absorption of heat during melting and evaporation, its release during condensation from steam and freezing.

7. Water is a universal solvent. Under laboratory conditions, absolutely pure water is not available. These and other properties of water have a huge impact on biospheric processes, all living beings and their habitat.

Water - almost the only source of replenishment of atmospheric oxygen during its decomposition in photosynthetic processes. It is also a condition for the migration of chemical elements and compounds, large and small cycles of substances.

Life on Earth originated in water. Until now, organisms (algae, etc.) have been preserved, in the body of which the amount of water depends on the degree of watering of the environment. The proportion of water in the human body is about 60%. Some biologically important properties of water are still poorly understood. Water is an important biological and social factor for human life. To meet biological needs, a person needs 2-5 liters of water per day. The determining factor of primitive human settlements and the centers of the origin of civilizations was water. Most often, settlements arose in the floodplains of rivers. Water is an essential element and condition of almost all technological processes.

29. Water reserves on Earth and its global circulation

World water reserves on Earth are equal to 1 thousand km353. If all the waters of the hydrosphere are distributed evenly over the surface of the Earth, its layer will have a thickness of about 985 km. Although the largest mass of water on Earth is salt water (3%), the volume of fresh water is also colossal, approximately 2,5 million km97,5.

The water balance of the Earth is formed as follows. Precipitation falling on the planet is balanced by evaporation. Both of these values are close to 577 km000/yr. Evaporation from the ocean exceeds precipitation by 3 km47/year. On land, on the contrary, evaporation is less than precipitation by 000 km3. Moisture returns to the ocean through river runoff.

At present, the world water balance is shifted towards the ocean. It receives more water than it evaporates at 430-550 km3/year. The result is a gradual rise in sea level. About 75% of the additional moisture in the ocean comes from melting glaciers, 18% from groundwater, and 7% from lakes. Underevaporation of precipitation on land (47 km000) is not associated with a lack of heat, but with the regulatory role of ecosystems. In the event that terrestrial ecosystems would lose the ability to regulate moisture circulation, this would inevitably lead to a colossal catastrophe: a decrease in fresh water reserves, the loss of mechanisms for its purification, and a sharp disruption of biological and other biospheric processes. Soil and vegetation cover are factors of water regulation in ecosystems. They form the conditions for water absorption into the soil and runoff along the soil surface. Therefore, part of the moisture of precipitation almost everywhere is fed to water sources and groundwater.

There are problems of water resources in terms of the volume of their entry into sources, as well as improving the qualitative composition.

Today such questions are solved mainly by purely technical methods. Among them are the construction of reservoirs, water purification by technical means, the redistribution of water resources between individual regions (through canals, water conduits), etc., although many of the water management tasks can also be solved at the level of ecosystems, within the framework of natural natural cycles. For example, almost the only source of moisture on the land surface is precipitation and partly condensation phenomena (dew, hoarfrost, etc.), and the consumption is evaporation and runoff. Thus, by changing the total evaporation, it is possible to change the runoff and moisture inflow to sources due to the replacement of some ecosystems by others or by influencing some structural components of existing ecosystems.

30. The problem of pollution or qualitative depletion of water.

Eutrophication of waters

All categories of water are subject to pollution, but to varying degrees.

Water quality indicators and their chemical composition

Water contains dissolved substances. The most common calcium, sodium, chlorine, potassium. The salinity of water is estimated by the total content of chemicals in it. The following categories of waters are distinguished: fresh, brackish, slightly saline, saline and very saline, brines. The waters contain organic matter and various suspensions. A person evaluates water depending on the purpose of its use: drinking, technical, etc. To assess the quality of water, maximum permissible concentrations (MPCs) are used. In addition to chemical, bacteriological and organoleptic (smell, color, turbidity, taste) criteria are used to assess the quality of drinking water.

Important water quality indicator - the presence of oxygen in them, which is expressed through the indicator of biological oxygen demand (BOD).

More and more non-biodegradable substances (organic solvents) appear in the waters. Their content is estimated through chemical oxygen demand (COD). The ratio of BOD to COD is the degree of water's ability to self-purify.

Distinguish primary и secondary water pollution. Primary associated with the release of pollutants into water bodies Secondary is a consequence of chain reactions occurring under the influence of primary pollutants. A large number of pollutants bring atmospheric precipitation. Oil and oil products are among the most dangerous and common pollutants. Thermal water pollution is a consequence of both water consumption and water use. Thermal and nuclear power plants are the most important supplier of heated water.

Significant negative environmental impacts are associated with reservoirs. Secondary pollution, such as eutrophication, also causes great damage to aquatic ecosystems. Under eutrophication waters understand their enrichment with biogenic elements, especially nitrogen and phosphorus. The consequence of eutrophication is the intensive growth of algae and other plants, the accumulation of organic matter and other products of the death of organisms in water bodies. This creates conditions for an increase in the number of decomposer organisms that feed on dead organic matter. Reducers intensively absorb oxygen. The end result is the deoxygenation of the aquatic environment. The result of anaerobic processes is the release of hydrogen sulfide, methane and other toxic pollutants into the environment.

31. Environmental consequences of the use of mineral fertilizers and pesticides

Mineral Fertilizers - an inevitable consequence of intensive farming. At present, their world production is 200-220 million tons/year, about 35-40 kg/year. per person. The environmental consequences of the use of mineral fertilizers are considered from three points of view: the local impact of fertilizers on ecosystems and soils into which they are applied; impact on other ecosystems, their links; impact on product quality, human health

Changes occur in the soil that lead to loss of fertility. To neutralize this, mineral fertilizers have to be applied to the soil. But many of them contain foreign impurities. In particular, the application of fertilizers can increase the radioactive background and lead to the accumulation of heavy metals. The main way to reduce these consequences is their moderate and scientifically substantiated use (the best doses, the least amount of harmful impurities, alternation with organic fertilizers, etc.). The effect of fertilizers on atmospheric air, as well as water, is mainly associated with nitrogen forms.

Nitrogen losses from fertilizers range from 10 to 50% of its application. Chlorine-containing fertilizers have a negative impact on the waters and their inhabitants. Phosphorus forms of fertilizers contain fluorine, heavy metals and radioactive elements. Mineral fertilizers have a negative impact on both plants and product quality, as well as on the organisms that use it.

At high doses of nitrogen fertilizers, the risk of plant diseases increases. Phosphorus and potassium, soften the harmful effects of nitrogen. But at high doses, they also cause mild types of plant poisoning. Chlorine-containing fertilizers (ammonium chloride, potassium chloride) have a negative effect on animals and humans through water. Pesticides are a group of substances that are used to kill or reduce the number of organisms that are undesirable to humans. Herbicides are substances used to kill plants; insecticides - insects; fungicides - mushrooms; acaricides - ticks. Pesticides include substances that repel organisms that harm a person or his products (clothes, buildings). Only about 1% of the poisons introduced into the environment have direct contact with the organisms against which they are used. The environmental hazard of pesticides depends on their toxicity, life expectancy. From an environmental point of view, the annual increase in the use of pesticides is of particular concern. This is due not only to the expansion of cultivated areas, but also to the habituation of organisms to pesticides.

32. Biological control measures for unwanted organisms

Biological methods for regulating the number of organisms undesirable for humans are based primarily on a deep knowledge of their biology and ecology. Pesticide-free technologies are increasingly being used in agriculture. In this case, the use of mineral fertilizers, growth stimulants, etc. is sharply reduced or eliminated. Such products are usually sold at higher prices, but this does not hinder their sale.

Biological control measures are as follows.

1. Predators and parasites of unwanted species, their breeding and introduction into ecosystems. Such organisms include ladybugs, ants, ground beetles, parasitic insects, and other species. About 300 species of antagonist organisms are currently bred on Earth.

2. Bacterial and viral preparations. The share of such drugs is about 10% of all biological means of combating unwanted species.

3. The introduction into the population of such individuals that are not able to produce offspring or transmit unviable lines to offspring. This genetic method is now being used more and more.

4. Preparations with a physical nature that have pesticidal properties:

1) Insect control with "diatomaceous earth" (dust from diatoms). The disastrous effect of this dust on insects is obviously associated with the clogging of the trachea during respiration. It is believed that this principle of pest control is used by birds bathing in the dust;

2) powders (silicone, etc.) are also used to control household insects.

5. Methods of dealing with unwanted species, organisms:

1) breeding methods, which are based on the breeding of varieties resistant to pests;

2) genetic engineering methods that increase the resistance of organisms to diseases and pests. This is possible by introducing foreign genes into the genome of organisms of interest to humans, which determine deterrent or poisonous properties. In particular, the resistance of tomatoes was significantly increased by the introduction into their genome of bacteria that produce proteins that can kill caterpillars and insect pests;

3) integrated methods. The use of combinations of biological, agrotechnical, breeding techniques with a significant reduction in the use of chemicals. These are transitional methods on the way to the complete abandonment of chemicals;

4) in the system of biological control methods, significant attention is also paid to increasing the diversity of cultivated plants and animals. It also reduces the chance of their loss by conserving resistant species (varieties or breeds).

33. Ecological consequences of modern animal husbandry practices

Have a great impact on the environment large livestock complexes. Cattle farms with 10 heads supply the same amount of pollution as the waste of a city with a population of 100-150 people. Raising only seven chickens is equivalent to one person in terms of waste. A 100-head pig farm emits about 1,5 billion microorganisms, 160 kg of ammonia, about 14 kg of hydrogen sulfide and 25 kg of dust into the atmosphere every hour. Large animal husbandry complexes are one of the main examples of putting economic interests ahead of environmental interests. Here, the cost of the products obtained is often noticeably reduced, production processes are mechanized and automated, and animal husbandry is being transferred to an industrial basis. But environmental costs are not always taken into account. This is due not to animal waste, but primarily to their quantity. In particular, manure has always been a blessing and a condition for the well-being of peasant farms. The manure taken to the fields was included in the circulation processes, without polluting the environment, and ensured an increase in productivity. When grazing livestock, there were also no big problems with environmental pollution, this was due to the fact that excrement was distributed evenly over pastures and thus included in natural cycles. But at large enterprises, with the concentrated maintenance of animals, positive phenomena began to turn into negative ones. In this case, there was an accumulation of harmful waste that has a devastating effect on ecosystems.

The negative impact of animal waste is reduced when it is used in a recycled form: composted or turned into manure by mixing them with straw, peat or small wood waste. Thus, waste is included in the cycle processes and in food chains. It is also important not to build livestock complexes near the places where people live, to preserve the most productive (in particular, forest) ecosystems around them. Zones near livestock complexes are called sanitary protection zones.

For poultry farms for 400-500 thousand heads, such zones, as a rule, should have a width of about 2,5 km, for pig farms for 100 thousand heads, about 5 km, and for pig farms for 200-400 thousand heads, already 10-15 km and more.

34. Forest fund of the planet and Russia. Parameters and criteria for forest management

Total area of forest land a little more than 4 billion hectares. Thus, there is about 1 ha of forest land per person. forest cover - this is the ratio of the total land area to the area that is occupied by forests, and expressed as a percentage. For our planet as a whole, this figure is close to 32,2% (according to other sources, about 25%). The area of all forests in our country is approximately 870 million hectares, and the forest cover of Russia is 44,8%. The area of Russia covered with forest is less than the total forest area by 105 million hectares and amounts to 765 million hectares. For each inhabitant of Russia, there are now about 5,8 hectares of total forest area and approximately 5,1 hectares of area that is covered with forest. During its history, people have destroyed approximately 2/3 of the entire forest area. Recently, great attention has been paid to the preservation and accounting of areas that are not affected or slightly affected by human economic activity. These zones are represented mainly by forest lands. In the world, the share of these lands is about 20%, in Russia - more than 60%. In some countries it is close to zero, and for Europe it averages 4%.

About 1,65 - 1,96 trillion m3 of biomass are concentrated in the forests of the planet. It includes the entire above-ground (leaves, trunks, branches) and underground mass. The wood of the trunks in the total mass is approximately 50%. One of the main indicators is the annual growth of forest timber. In order for the use of the forest not to be exhausting, it is possible to remove no more than such a volume of wood per year that grows in this area (calculations are based on stem wood). From the forests of the world it is permissible to withdraw annually about 5,5 billion m3 of wood (i.e., their annual growth), and from the forests of our country about 500 million m3. And in the first and second cases, the allowable cutting area is used only by 50-60%. But this does not mean that in Russia and in the world the problem of depletion of forest resources is completely absent. As a rule, forest management is calculated for all forests, and cuttings are carried out in forests where it is economically beneficial for a person. In particular, in Russia the main logging sites are located in the European-Ural region, and the main forest zones and thus the increase in timber are in Siberia and the Far East. Therefore, in the first region, the removal of wood is 2–2,5 times higher than the permissible limits, and in the second, all mature wood is not cut down. The extent of deforestation comparable to logging is often associated with forest fires. According to official data, every year Russia's forests are cut down on an area of 2 - 2,5 million hectares. On average, the same amount of forest suffers from fires.

35. The most important ecological functions of forests

When assessing the ecological functions of forests, there are two types of impact on the environment: biogeochemical and mechanical. Biochemical activity is physiological processes (photosynthesis, mineral nutrition, etc.). Mechanical activity carried out through biomass Biomass - the mass of living organisms or individual components contained per unit area or volume of ecosystems.

Productivity - the rate of biomass formation.

Carbon function of forests. Great hopes for removing excess carbon from the atmosphere and solving the problem of the greenhouse effect are associated with forest ecosystems. In the formation of 1 ton of plant products, 1,5 - 1,8 tons of carbon dioxide are used and 1,1 - 1,3 tons of oxygen are released. The concentration of large masses of carbon in forests is associated with a large biomass of forest stands. Of the entire mass of carbon concentrated in the plants of the globe, 92% is contained in forest ecosystems.

Air purifying functions of forests. Forests are able to remove other foreign substances besides carbon from the air. The purification of air from pollutants is carried out both as a result of their absorption and through physical precipitation. 1 kg of leaves can absorb in one season about 50-70 g of sulfur dioxide, 40-50 g of chlorine and 15-20 mg of lead.

Forest plantings significantly reduce the noise effect. They also protect roads from snow drifts, reduce air flow resistance to traffic.

Climatic and meteorological functions of forests. Forests affect atmospheric phenomena and thus create their own specific environment, microclimate. This property is used to protect soils, roads, crops, settlements, etc. The forest is characterized by high humidity of the air and upper soil layers. In the depths of the forest, there is usually almost no wind at all. At night, you can observe air currents of the opposite direction. These air movements are of great ecological importance. Thanks to them, the concentration of carbon dioxide is leveled.

Water protection functions of forests. Forests have a positive impact on groundwater recharge. This is due to the transition of a significant part of surface water into groundwater. Groundwater, feeding the rivers, provides a high level of water in them both in winter and in summer. The main reason for the increase in groundwater runoff by forests is the preservation of good water permeability of soils under them. The positive impact of forests on water quality is associated with the process of their filtration through the soil-ground layer, as well as the water-purifying ability of plants.

36. Problems of forest sustainability under anthropogenic pressures. Tropical Forest Specific Problems

The function of cleansing the environment, which forests perform, leads to their damage, decrease in stability and death. The death of forests from atmospheric pollution is one of the main environmental problems of our time.

The most general patterns of destruction and destruction of forests and measures to reduce the damage of this phenomenon are as follows.

1. Exposure to sulfur dioxide and its derivatives. Significant damage is also caused by nitrogen oxides, fluorine, ozone, chlorine, and photochemical smog substances. Poisons act on plants either as dry precipitation or as acid precipitation. Integumentary tissues of trees, cellular structures are destroyed to the greatest extent. Acid rain acts by leaching nutrients from various parts of plants, poisoning and destroying root systems. Coniferous forests are most susceptible to damage. The main reason for this is the poisoning of long-lived (5-7 years) needles. Soft-deciduous tree species (birch, alder, aspen) are more resistant. Near cities and industrial centers, it is they who replace coniferous forests. To reduce the effect of pollution, soil fertility is increased (fertilizers, irrigation), accelerate the renewal of phytocenoses, create edges around forests - a barrier to the penetration of pollutants.

2. Recreation - restoring the health and working capacity of a person by resting outside the home. Forests and forest landscapes are widely used as recreational objects. The task of recreational forestry is to develop measures to regulate the pressure on forests, reduce damage to ecosystems and forestry in general. The most important activities: planting forests of small-leaved species (birch, aspen), which are more resistant to stress than coniferous forests.

Tropical forests account for 5% of the land, about 20% of the total forest area. At the same time, more than 50% of the total plant mass of land is in tropical forests. Tropical forests are being destroyed at a rate of 20-25 hectares every minute for the use of timber and in order to free up areas for agricultural land. The biomass of the world's forests now contains about 1,5 times more carbon than in the atmosphere, in the humus of forest soils it is 4 times more than in the atmosphere. If in northern forests the bulk of carbon is in forest soils and litter, then in tropical forests carbon is mainly in wood. As a result, when tropical forests are destroyed, carbon is almost completely released from these spaces.

37. Biodiversity. Red Books. Specially Protected Areas

Preservation biodiversity is of great ecological importance. To date, several thousand species have been registered that are suitable for use in the human diet. But in reality, no more than 200-250 species of animals and plants are used in significant quantities. The main part of agricultural production, people receive in the process of using only 12-15 plant species. Wild species are an invaluable source for obtaining products from natural ecosystems, especially for breeding new breeds and varieties of agricultural plants and animals. Biodiversity is a source of energy and technical resources for a very long time. Diversity is one of the main factors and conditions for sustainable relationships in ecosystems. Species saturation is the most important, although by no means the only component of ecosystem diversity.

Red Books. One of the measures to attract people's attention to environmental problems and the conservation of biological diversity are the Red Books. There is a Red Book of the entire planet. Within individual states - regional Red Books. Red Books are also compiled separately for plants.

Rare and endangered organisms are listed in the Red Books. Usually their approximate number and reasons for its reduction, ranges in the past and at the present time, necessary measures for protection are indicated.

Specially protected objects or territories - these are areas of the biosphere, completely or partially excluded from economic use. The categories of protected areas in Russia include nature reserves, wildlife sanctuaries, national parks, biosphere reserves, and especially valuable objects.

nature reserves Territories completely withdrawn from economic use are called. Their visits and tourism are limited. Biosphere reserves are reserves that have an international status and are used to monitor changes in biospheric processes. Now biosphere reserves have been identified in the territories of more than 60 countries of the world, their number exceeds 300. In 1991, there were 75 reserves on the territory of Russia.

В national parks allocate reserved, recreational and economic zones. There are now more than 2300 national parks in the world.

Territories with a less strict protection regime - reserves. They restrict economic activities in order to protect one or more species of living beings. There are more than 1,5 thousand reserves in Russia.

The share of all protected objects in Russia accounts for approximately 10% of the territory.

38. Environmental monitoring

Monitoring - tracking any objects or phenomena. Environmental monitoring -

observation and forecast of the state of the natural environment, assessment of its changes under the influence of human activities. The data obtained is used to eliminate or reduce the possibility of negative environmental situations, the protection of natural objects, the preservation of the environment, and human health.

Types of environmental monitoring.

1. On a territorial basis: local, regional and global types of monitoring.

2. By observation methods: space, aviation, ground.

3. By methods of research physical, chemical, biological.

Observations from space make it possible to get an idea about changes in the biosphere that cannot be detected with other methods, about the degree of pollution of the ocean, other water bodies, to reveal the nature of pollution (oil film, detergents, etc.). Observations of this type are used to detect certain catastrophic phenomena (eg, landslides, fires, etc.).

Aviation observations are oriented, in contrast to space ones, to regional or local phenomena.

Ground monitoring carried out for two purposes:

1) To clarify the data obtained from space or aviation observations;

2) observations that cannot be performed by other methods (determination of the chemical characteristics of the surface layer of air, soils).

RџSЂRё ground monitoring often use biological methods of observation, plants that are most sensitive to individual influences. These types are called bioindicators. For biological observations, the concentration function of living organisms is also used - their ability to accumulate certain pollutants. The analysis of this material makes it possible to identify such pollutants that are difficult to determine by other methods due to their low content in the environment. Together with observations of indicator plants in natural conditions, the method of exposure of some indicator plants in cities, industrial enterprises, indoors, etc. is often used.

Plants - indicators and pollutants: lichens, mosses - heavy metals; plum, common bean - sulfur dioxide; spruce, alfalfa - hydrogen fluoride; warty birch, strawberry - ammonia; sunflower, horse chestnut - hydrogen sulfide; spinach, peas - photochemical smog; soybean, touchy common - hydrocarbons.

39. Environmental problems of cities and settlements

Among the most significant phenomena of our time, which determine the characteristic environmental problems, include rapid urban growth and urban population. Today, the proportion of the world's urban population is approximately 45% (2,5 billion people). The number of metropolitan cities is intensively increasing. In 1950 there were three of them (New York, London, Shanghai), now there are more than 20. The population of Mexico City is 15 million people, and according to some forecasts, by 2010 it will increase to 30 million. By 2020, about 40% of the land will be under urban development in the world. Cities are human creations, adaptation to which is associated with significant costs to human health.

Atmospheric air pollution. In large cities, up to 60-80% of atmospheric air pollution is accounted for by motor vehicles. On average, one car in the city emits about 200 kg of carbon monoxide, 40 kg of hydrocarbons, 60 kg of nitrogen oxides, 3 kg of metal dust, 2 kg of sulfur dioxide per year.

Smog - this is the result of the complex action of various pollutants. Previously, it was understood as a mixture of dust particles and fog droplets. Now the term has a broader meaning.

There are three types of smog.

1. London (or wet) smog - a mixture of dust particles (soot, ash), fog and some chemical pollutants. It usually forms at 0°C and calm weather. At the same time, the concentration of harmful substances in the surface layer quickly reaches dangerous values for human health. Smog affects the respiratory system, disrupts blood circulation.

2. Ice (or Alaskan) smog. It is formed more often at low temperatures and a small amount of solar radiation. Its action is similar to London.

3. Los Angeles (or photochemical) smog - a consequence of secondary air pollution under the influence of photochemical reactions. A prerequisite for its formation is the presence of pollutants, temperature inversion and a significant amount of solar radiation. This phenomenon is typical for the subtropics.

dust pollution are also a product of the urban environment. The air of an average city has a concentration of dust 150 times greater than the air over the ocean, and 15 times more than the air in the countryside.

Noises. Excessive noise leads to headaches, insomnia, hearing damage, nervous disorders, constriction of blood vessels and increased blood pressure. It also causes or enhances stressful phenomena, stimulates aggressiveness, leads to a reduction in life expectancy.

40. Cities and disasters

The overcrowding of the population in cities leads to greater deaths in disasters, in particular earthquakes, than in rural areas. Megacities themselves often provoke catastrophic events due to their strong impact on the natural environment. The amount of damage from disasters increases by 6% every year. There is a very clear pattern: the lower the socio-economic and technical level of urban development, the greater the probability of death in disasters. For example, in the cities of Asia, in relation to the total population, death is twice as high as in Europe. Now about 250 thousand people die every year from disasters on the planet, and the damage from disasters is about 40 billion dollars annually. Despite the increase in the protection of the population from disasters, the damage from them does not decrease. One of the main reasons for this is the increase in disasters caused by man-made phenomena associated with cities, either directly or indirectly.

Causes of disasters.

1. Lowering of territories and flooding. These phenomena often lead to subsidence of the soil, the destruction of buildings. For example, in Tokyo, due to groundwater pumping, the earth's surface was observed to sink by 4,5 m in 50 years. In Mexico City, soil subsidence reached 9 m. In California, the lowering of the terrain occurs by 30-70 cm per year due to oil and gas production. Flooding of urban areas is often observed. In Russia, this phenomenon is experienced by about 2/3 of all cities with a population of about 100 thousand inhabitants each. The loss from them in 1994 was estimated at 60 trillion rubles.

2. Karst-suffosion failures. They are primarily observed where the geological structures consist of soluble rocks (chalk, limestone, gypsum).

3. Technogenic physical fields are associated with stray currents, vibrations, thermal pollution. At the same time, currents accelerate the corrosion of metals by 5–10 times.

4. Induced seismicity is caused or accelerated by technogenic processes. These processes include the injection of various substances into the deep layers of the lithosphere, underground atomic explosions, etc. Today, there are repeated confirmations of the connection between the beginning of earthquakes and the construction of reservoirs. Such a connection was recorded in Australia, Brazil, Canada, the former USSR. Underground nuclear explosions can have a twofold effect. They are capable of provoking an earthquake, but on the other hand, they can also prevent them by removing the stresses existing in the earth's layers.

41. Some ways of solving environmental problems of cities.

Ecopolises

Since the growth of cities is an inevitable phenomenon of modern times, humanity must look for ways to ease the pressure of urban civilization on the environment and its health. The main ways to solve this problem are the greening of the urban environment through the formation or preservation of natural or artificially created ecosystems (botanical gardens, forest parks, squares, etc.) within the boundaries of urban settlements. Such settlements, where urban development and natural landscapes are combined, are today called ecopolises or ecocity In urban construction, the term "ecological architecture" is often used. We are talking about the development of urban areas, in which the social and environmental needs of a person are taken into account as much as possible: bringing him closer to nature, freeing him from the monotony of space. At the same time, some eco-urban developments are very interesting, in which an increase in the share of ecological space in cities is achieved, as a rule, not due to the development of new territories. Here, such activities are carried out as moving non-residential (communal and other) premises to underground structures, transferring dwellings to autonomous energy supply, creating green walls and hanging gardens, greening the roofs of houses. The construction of houses elevated above the soil, which is used for landscaping, is being introduced into practice, the water permeability of road surfaces and other areas is increased, noise-protective green walls are created, natural materials are used for construction, etc. Modern architects also propose the creation of an additional drinking water supply system, into which high-quality water is supplied with a volume of no more than 3 - 4 l / day per person.

The second way to bring a person closer to the natural environment is the expansion of suburban areas and their formation according to the type of ecopolises. They are becoming more and more widespread around large cities, especially due to the rapid development of communications and transport routes. In the US, more than 50% of city dwellers have homes in the suburbs.

However, it must be remembered that this is an extensive way of greening cities. It also has negative consequences. Thus, the expansion of suburban developments is likely to exacerbate rather than solve environmental problems. The development of cottages in the suburbs is associated with a significant alienation of land, the extermination of natural ecosystems, and their destruction. Construction in the suburbs is inevitably associated with the use of large spaces for laying roads, water pipes, sewers and other communications.

42. Environmental problems of energy

In today's world, energy needs are met mainly by three types of energy resources: organic fuel (gas, coal), water and atomic nucleus. A person uses the energy of water and atomic energy after turning it into electricity. At the same time, a large amount of energy contained in organic fuel is used by humans in the form of heat, and only part of it is converted into electrical energy. At the same time, both in the first and in the second cases, the release of energy from organic fuel is associated with its combustion and, thus, with the release of combustion products into the environment.

Energy today is decisive for both the economy and the environment. It is on it that the economic potential of all states and the well-being of people largely depend. It also has a very strong impact on the environment of the ecosystem, the biosphere as a whole. The most pressing environmental problems (climate change, acid rain, general environmental pollution) are directly or indirectly related to the use or production of energy. It is energy that holds the first place, both in chemical and other types of pollution: thermal, electromagnetic, aerosol, radioactive. Therefore, it would not be an exaggeration to say that the possibilities of solving the main environmental problems depend on the solution of energy problems.

By burning fuel (including firewood and other natural resources), approximately 90% of energy is produced today. The share of heat sources is reduced to 80-85% in electricity generation. In industrialized countries, oil and oil products are mainly used for transport needs. In particular, in the United States, oil in the country's total energy balance is 44%, and for electricity generation - only 3%. For coal, the opposite pattern is inherent. In the general energy balance - 22%, but as the main source for obtaining electricity - (52%). In China, the share of coal in electricity generation is about 75%. In Russia, the predominant source for generating electricity today is natural gas (approximately 40%), coal accounts for only 18% of the generated energy, and the share of oil is no more than 10%.

On a global scale, hydro resources are used to produce about 5-6% of electricity (but in Russia - 20,5%). Nuclear power generates 17-18% of electricity. In Russia, its share is about 12%, although in some countries it is predominant in the energy balance (France - 74%, Belgium - 61%, Sweden - 45%).

43. Environmental problems of nuclear power

Energetics - an industry that is developing at an unusually fast pace. If the population in a population explosion doubles in 40-50 years, then the production and consumption of energy doubles in total every 12-15 years, including per capita.

The pace of energy production and consumption will not change significantly in the near future (some slowdown in industrialized countries is offset by an increase in the power supply of third world countries) element on earth. Energy is contained within each atom. It is one of the main sources of energy that is not associated with fossil fuels. Unlike oil and coal, energy produces electricity without smoke, but hazardous radioactive waste is generated at every step of the nuclear process. Nuclear power is associated with an increased danger to people. In this regard, it is necessary to solve safety problems (prevention of accidents with a reactor runaway, localization of an accident within the limits of bioprotection, reduction of radioactive emissions, etc.) at the reactor design stage. Nuclear power plants emit very dangerous nuclear waste that can cause cancer, mutation (DNA changes) and even death. Before radioactivity disappears, 80 years must pass, provided that during this time its causes are eliminated. Today, liquid waste is simply pumped into the seas, gaseous waste into the air. The stock of solid waste is being cared for. A small part of them is now dumped into the sea. Basically, hazardous waste is buried and also stored on the ground in containers, in which gaps can appear at any time. Therefore, it is worth considering such proposals to improve the safety of nuclear power facilities, such as building nuclear power plants underground, sending nuclear waste into outer space.

44. Alternative energy sources

Wind energy. A significant disadvantage of wind energy is its variability and variability over time, but these factors can be compensated for by a certain location of wind turbines. If, under conditions of complete autonomy, several dozen large wind turbines are combined, then their average power will be constant, and mechanical energy can be directly obtained from the wind turbine. Working wind turbines have a number of negative phenomena. For example, the spread of wind turbines makes it difficult to receive TV programs and creates powerful sound vibrations.

Tidal energy. The tides raise and lower the Earth's oceans twice a day. Tidal power plants use this water to generate electricity. A dam is being built across the mouth of the rivers. Inside the dam, water turns turbines and generates electricity.

solar energy. The main source of most of the energy is the Sun. It helps plants grow, controls the wind and waves, and makes water evaporate. The upper boundary of the Earth's atmosphere in a year reaches a huge flow of solar energy. The Earth's atmosphere reflects 35% of this energy back into space, and the rest of the energy is spent on heating the earth's surface, the formation of waves in the seas and oceans.

The annual amount of solar heat is equivalent to the energy received from 60 billion tons of oil. In California, in 1994, a solar-gas station with 480 MW of electric power was put into operation. At night and in winter, energy is provided mainly by gas, and in summer during the daytime - by the sun.

One of the leaders in the practical use of solar energy is Switzerland. About 2600 solar installations based on silicon photoconverters have been built here, with a power of 1 to 1000 kW. Solar installations practically do not require operating costs, they do not need repairs. They can work indefinitely.

Just one hundredth of solar energy, used at 5% efficiency, will give every country in the world as much energy as the United States currently consumes. The problem is how to use it.

Coal and other fossil fuels are very easy to use as they carry energy that has been concentrated for millions of years. Sunlight can be converted into electricity using solar cells, but since it spreads over vast areas, it is difficult to collect it in large quantities. The same problems arise when trying to "subdue" the wind, as a result, these types of energy are difficult to use in industrial volumes.

45. Demographic problems and health of the population of Russia

Russia has its own specific demographic problems: the life expectancy of the country's inhabitants is rapidly decreasing. In 1987, the average maximum life expectancy was recorded for men - 65 years, and for women - 75 years; in 1994 - less than 60 years (and now - 57-58 years) for men, which is 15-20 years less than in Germany, France, Japan.

Russia is not the only country with negative population growth. This phenomenon is typical for Germany, England, etc. But if in these European countries the decrease in the birth rate is considered as a natural process of a consumer society, then in Russia it is the result of a deterioration in well-being.

The decrease in the birth rate and life expectancy is more pronounced in the central regions of the Russian Federation. The children's health is of concern. The decrease in the birth rate is accompanied by high infant mortality. Only 14% of the examined selectively children were recognized as practically healthy, 50% had deviations in their state of health, and 35% had chronic diseases. From 30 to 40% of childhood diseases are associated with air pollution and the consumption of poor quality water. The relationship between the incidence of hepatitis, acute intestinal diseases and water quality is clearly expressed. About 20% of the waters used in the country for drinking needs are recognized as poor-quality in terms of chemical indicators and 11% - in terms of bacteriological indicators. A large number of diseases are determined by the use of poor-quality products. From 5 to 10% of food products contain heavy metals, 8 - 10% are of poor quality in terms of bacteriological indicators. The concern of doctors is associated with the deterioration of the genetic fund of the population.

The decrease in life expectancy, the deterioration of health is more significant in cities with a high degree of environmental pollution. These cities include, for example, Kemerovo, Nizhny Tagil, Norilsk, Cherepovets, Sterlitomak, etc.

Specific to Russia ratio of life expectancy of rural and urban population. In many other countries, life expectancy in rural areas is much or significantly longer than in cities. In Russia, the opposite trend is taking place. This is probably due to the fact that the negative aspects of industrial civilization are concentrated in the Russian countryside (the use of imperfect equipment, the lack of the necessary control over compliance with safety regulations, etc.). Very often rural residents do not receive medical care.

46. Water resources of Russia

Russia has significant water resources. Average annual runoff of rivers in Russia accounts for about 10% of the global, more than 4200 km3

The largest river in Russia is the Yenisei. Its average annual runoff is about 630 km3/year, the second largest is the Lena (532 km3), then the Ob (404 km3), Amur (344 km3). In the European part of the country, the largest river is the Volga (254 km3), the catchment of which is about 70% of this territory. Reserves of usable groundwater in Russia are also large. Approximately 230 km3 of these resources are used annually, which is only 15-17% of their reserves (80% is consumed from surface sources).

In addition to direct consumption from sources, a large amount of water is in the water circulation of consumers and is used repeatedly (about 160 km3/g). As a result, the total water use in the country is close to 280 km3/year, about 2000 m3/year. per person (approximately 5 m3/day).

In relation to total water resources, water consumption in the country is low. Water abstraction from surface sources is only 3% of the annual flow (on average in the world about 7 - 8%).

The problems of water resources security typical for Russia are determined by several important reasons.

1. Uneven distribution and use of water across the country. The Caspian and Azov-Black Sea basins, where 80% of the country's population lives, account for only 9% of Russia's total river flow. The water supply here is only 5,5 thousand m3/g per person. In the northern and eastern regions, the water supply is 82 thousand m3/g per person. The lack of water resources in the European territory of the country is aggravated by large withdrawals of water. Groundwater is also used more in the European region. In places of intensive water intake, depletion of groundwater reserves is observed.

2. High degree of water pollution. About 70% of the rivers and lakes in Russia have lost their original qualities as sources of drinking water supply. Part of the groundwater is also polluted. About half of the Russian population consume poor quality water.

3. A large proportion of pollution or their consequences from the alloy of wood, transportation of petroleum products, spills of fuels and lubricants.

4. Uneconomical, wasteful use of water resources in all sectors of the economy: in agriculture, in everyday life and in certain industries. In cities, sometimes up to 400-500 liters of water per day per person are spent for domestic needs. Although in many countries daily expenses are not more than 200-250 liters per person.

47. Soil resources of Russia

In almost all categories of land, their area per capita in Russia is higher than in the world. Area of arable and other cultivated land

about 150 million hectares. On a per capita basis, this is 4 times higher than the world average. There are also significant differences across forest lands. In Russia, the forested area alone is 765 million hectares, about 5,1 hectares per person (the world average is 0,77 hectares). In addition to those covered with forests, the forest fund includes part of the land that is currently under swamps, shrubs, hayfields and other lands - about 940 million hectares (6,3 ha / person). Many soil areas are characterized by low fertility. These are primarily the soils of the southern part of the steppe and semi-desert zones, the forest zone. Their melioration (improvement) will require the investment of significant funds and energy, a high culture of agriculture.

In most of the country's soils, a low level of agricultural culture and a lack of real interest in their conservation remain. Of the 140-150 million hectares of arable land, at least 60 million hectares are damaged by erosion. The area of irrigated land is about 6 million hectares, drained - 6,3 million hectares. Approximately 1/4 of these soils is severely disturbed (secondary salinization, waterlogging, erosion) and requires reconstruction.

The tendency of soils to lose the main factor of fertility - humus - continues. Some arable chernozems have lost it up to 50% of the original. Large areas of soil are polluted by industrial emissions. As a result of the accident at the Chernobyl nuclear power plant, soils on an area of approximately 2 million hectares were subjected to radioactive contamination.

The loss of land as a result of their use for various types of construction is very high. Thus, as a result of the construction of hydroelectric power stations on the rivers of the European territory of Russia, more than 6 million hectares of land were flooded or heavily flooded, although about 50% of them are the most fertile floodplains. In general, for the period 1960-1980 - s. the arable fund of the former USSR lost at least 30 million hectares of land (most of them are in Russia).

In the 1970s-1980s. it was natural to strive to reduce the area of arable land by about 0,01 ha/g. per capita. If this trend continued, then the country would be threatened with a complete loss of arable land within the next century. Recently, this process has stopped, but, unfortunately, not as a result of a more reasonable use of land, but due to a significant slowdown in industrial and other types of construction, the cessation of population growth, and for some other similar reasons.

48. Forest resources of Russia

Despite the huge amount of forests, Russia is faced with exhaustion problem forest resources. This phenomenon is especially characteristic of the European-Ural region, as well as the forests of the eastern regions of the country, which are largely accessible for transport. The presence of vast forest areas, unaffected or slightly affected by human activity, hardly changes the situation; these are either low-productive forests or forests that are located in hard-to-reach areas.

The timber industry is one of the most wasteful industries. Only 20-30% of the harvested wood is used. In addition to leaving a large part of the wood in the cutting areas and losses during transportation, there are very large losses of wood during processing.

The country also continues to export wood in the form of logs, which is considered to be the most irrational way of trading wood raw materials (low prices, lack of development of domestic wood processing). With significant volumes of harvested timber, Russia ranks only 32nd in the world in paper production per capita (40 kg/g). The wastefulness of forestry and the timber industry is manifested not only in the loss of timber and its mismanagement. These include unreasonably large areas of deforestation, destruction of forest soils, swamping of territories, shallowing of rivers and other environmental violations. After irrational logging, forests lose their ecological functions for a long time, recover very slowly or are replaced by less productive ecosystems.

In most farms of the European-Ural region, the scientifically based norms for the removal of timber have long been exhausted, although even today approximately 2/3 of the total volume of timber is harvested in this region. An inevitable consequence of the use of heavy machinery in felling is a decrease in its fertility, an increase in the processes of waterlogging or soil erosion. The reduction of forested areas often occurs as a result of fires. Restoration of forests is slower than their destruction. Forest plantations are carried out annually on an area of only 0,5 - 0,6 million hectares / year. But such measures often do not reach their goal, as the plantings die due to lack of care for them. Shrubs and low-value deciduous tree species also grow in their place. Environmentally more acceptable soft methods of forest management. These include non-continuous felling or felling by small cutting areas. Most often, the main reason for negative human activity in forests is the prevalence of short-term practical goals over long-term environmental ones.

49. Energy and other types of resources of Russia

Today, more than 2/3 of electricity in the country is generated at thermal power plants. To share hydropower and nuclear power accounts for about 1/3 of the energy received.

Prior to the accident at the Chernobyl nuclear power plant in Russia, priority was given to nuclear energy as cleaner. Energy production at nuclear power plants in the country reached approximately 12,3% (with 46 operating reactors). Now 28 nuclear reactors are operating in Russia, the share of nuclear energy in the energy balance is about 11%. The pace of construction of nuclear power plants has slowed down significantly. In the future, the development of thermal power plants.

The most promising energy sources for the country are natural gas and coal. The share of oil and oil products for generating electricity is gradually decreasing. Russia has significant reserves of natural gas. They are equal to 31 trillion m3, which is about 40% of the world. It is likely that in the future the share of coal as a source of energy will increase. Coal can be used as an energy carrier for 150-200 years. More than 40% of the world's coal reserves are concentrated in Russia. But, if the share of coal in energy production will increase, then the severity of the problems of environmental pollution will increase dramatically. The situation will be aggravated by the fact that the main coal reserves are high-ash types with a high concentration of sulfur and other impurities. In many countries there is a restriction on the use of coal by ash content. The losses of fuels and other minerals during their extraction are great. For example, the extraction of oil from fields, as a rule, does not exceed 30% of its reserves in the subsoil. The main production methods are often associated with the injection of water to increase the pressure in the reservoirs. This is usually followed by a sharp rise in the cost of the extracted raw materials, the extraction of a large amount of water to the surface along with oil, which becomes an unpleasant pollutant for soils, ecosystems, and water bodies. About 30% of the world's iron ore reserves are concentrated in Russia. Significant reserves of other ores, including non-ferrous metals. The extraction and use of these resources also cannot be assessed satisfactorily. The metal consumption of products is high. A large number of valuable products are lost with waste and slag. Their share included in processing is extremely low. In general, environmental costs from the extraction and use of energy and other resources are often due to the very insufficient use of low-waste, resource-saving and environmentally friendly technologies.

50. Particularly environmentally unfavorable territories of Russia

The unfavorable ecological situation in many regions of Russia is evidenced by the allocation ecological disaster zones и zones of emergency environmental situations. Their allocation is provided for by the Federal Law of January 10.01.2002, 7 No. XNUMX-FZ "On Environmental Protection". According to this Law, areas where human activity has caused profound irreversible changes, resulting in a significant deterioration in public health, disruption of natural balance, destruction of natural ecosystems, degradation of flora and fauna, can be declared zones of ecological disaster.

Areas with an unfavorable ecological situation.

Black Sea. Many experts assess his condition as critical. The main reason for it is contamination with phenols and surfactants. In some natural waters, the maximum allowable concentrations of these pollutants are often exceeded by 30-50 times.

Barents Sea. The ecological state of the sea is assessed as crisis-critical, and in some places as catastrophic. The main reasons are severe pollution (phenols and oil slicks) and unacceptably high exploitation of biological resources.

Baltic Sea. This sea experiences large anthropogenic loads, while it has a reduced ability to self-purify. It receives a lot of effluents, sources of both chemical and thermal pollution. The sea is also characterized by a high level of pollution with phenols, phosphorus, and heavy metals.

North and White Seas. The state of the seas is assessed as pre-crisis, and in some places as crisis and catastrophic. It is associated with pollution by oil, phenols and products of the forestry complex, reduced self-cleaning ability due to low temperatures.

Waters washing the shores of Russia in the east and northeast. The ecological situation is very unfavorable in some parts of the coast of Kamchatka. Thus, in the Kamchatka Bay, oil pollution reaches 4-6 MPC.

The Volga River and its basin. Both the water artery itself and its basin are ecologically overloaded. The river practically ceased to exist as a dynamic transit ecosystem. The incidence of fish has increased sharply. At present, due to the crisis in industry and agriculture, the condition of the Volga, like other rivers, has noticeably improved.

On the territory of Russia there are at least 70 cities where the MPC for the content of harmful substances is regularly exceeded by 5,10 or more times. Among them are Moscow, Volgograd, Saratov, Samara, Ufa, etc.

51. Destruction of ecosystems. desertification

Among the environmental damages that have the longest history and brought the most damage to the biosphere, include destruction of ecosystems, & lt; / RTI & gt; desertification, i.e., the loss of the ability to self-regulate and self-heal. Vegetation in this case is destroyed, and soils lose their main quality - fertility.

Desertification accompanied man from the moment of his transition to a primitive economy. This was facilitated by 3 processes: soil erosion, removal of chemical elements from the soil with the harvest, secondary soil salinization during irrigated agriculture.

Often these processes were superimposed on adverse climate change, its aridity. Vast sandy expanses located in the river valleys of the steppe zone have repeatedly been subjected to soil erosion by wind and complete or partial desertification.

Such phenomena of destruction and formation of ecosystems could be repeated more than once, which was reflected in the relief, landscapes, and structure of the soil cover.

The most common cause of destruction was overgrazing and then wind erosion. In later times - the impact of technology, plowing virgin soils. In the 1960s, during the development of virgin and fallow lands, almost all plowed light soils - about 5 million hectares - were turned into mobile substrates. Enormous efforts were required to stop this process by afforestation, grass planting, etc. The return of such lands to intensive use (pastures) will take a long time.

Desertification is still going on. In particular, the most valuable chernozems of Kalmykia are being destroyed. With a grazing rate of no more than 750 thousand heads of sheep, 1 million 650 thousand heads were grazing here all the time. In addition, more than 200 thousand saigas lived here. Pastures were overloaded 3 times. As a result, out of 3 million hectares of pastures, 650 thousand hectares have turned into shifting sands. The desertification of the northern outskirts of the Sahara, the Sahel (the transitional zone between the desert and the savannah), is acquiring catastrophic proportions. Its desertification is also caused by large pressures on ecosystems, intensified by long droughts in the 1960s and 1970s. Successful control of the tsetse fly also contributed to desertification. This made it possible to sharply increase the number of livestock, followed by overgrazing, the impoverishment of pastures, and, as a result, the destruction of ecosystems.

About 53% of Africa and 34% of Asia are affected by desertification to some extent. In general, in the world every year about 20 million hectares of land turns into deserts.

52. Ecological lessons. Caspian and Aral Seas

Caspian Sea - a closed internal reservoir, rare in terms of its richness in fish. In the past, it provided about 90% of the world's sturgeon catch. Now sturgeons are endangered. The reason for this is poaching fishing, water pollution, disruption of spawning sites due to the construction of dams on rivers. The sea is today in a state of crisis, it is deprived of the properties of self-regulation and self-purification.

For the Caspian, periodic fluctuations in water levels were natural. From 1820 to 1930 sea levels remained relatively stable. But in the 1930s began an intense drop in the sea level. By 1945 it had fallen by 1,75 m, and by 1977 it had fallen by 3 m below the mark of the beginning of the century. The surface area of the sea has decreased. It was expected that by the year 2000 the water level in the sea would drop by another 3-5 m, and the reservoir would lose its fishery importance, collapse as an ecosystem, and large economic investments would be needed in connection with the transfer of ports, villages, etc.

It was decided to take measures to stop or slow down the fall in sea level. But even before the completion of construction, the water level in the Caspian began to decrease rapidly. It was clear that the main cause of sea level fluctuations was not anthropogenic, but natural factors. The main conclusion from this environmental lesson is that any large-scale decisions on the impact on the natural environment must be preceded by a full analysis of the phenomena. Good intentions did not reach the goal, but aggravated the negative phenomena of the destruction of the Kara-Bogaz-Gol Bay as an ecosystem.

Aral Sea was an inland reservoir with slightly saline waters. It was second in size after the Caspian Sea. The drop in sea level has increased significantly since the 1960s, when water began to be withdrawn for irrigation. In addition, a significant amount of it was diverted to the Karakum Canal. By the mid-1980s, the sea level dropped by 8 m, in the 1990s - by 14-15 m. The volume of water in the sea decreased by more than 50%.

So, due to the lowering of the water level, the sea as an ecosystem ceased to exist. It broke up into two reservoirs, the salinity of the water in it increased 3 times. This was followed by the death of the most productive ecosystems, the impoverishment of the species composition of flora and fauna. Serious environmental costs in the Aral Sea region are associated with the construction and operation of the Karakum Canal. This is the result of irrational and mismanagement of the most valuable water resources. In the area of the Aral Sea and the Aral Sea region, an environment of an ecological disaster zone has been created.

53. Ecological problems of freshwater lakes

The problems of freshwater lakes are in many ways similar to those of inland seas.

Lake Baikal - a unique body of water in the world. The largest body of water in terms of volume of fresh water contained in it. The water in Baikal is exceptionally clean. Of the 2500 species of animals and plants living in it, more than 50% live only in this reservoir.

The ecosystem of Baikal is characterized by high sensitivity to various kinds of influences. The reasons for this are the poverty of waters in nutrients, low temperatures and the sensitivity of many organisms to environmental changes. The greatest concern of scientists for the fate of the lake is associated with the work of the Baikal Pulp and Paper Mill. From the beginning of its operation, Baikal waters have been intensively polluted. The destruction of forests in the catchment area caused a violation of the hydrological regime and the destruction of soils. The part of the lake adjacent to the plant has pollution exceeding the permissible limits (MAC).

Ladoga and Onega lakes - a large reservoir of fresh water. Its volume is about 900 km3, and the area of the lake is larger than the territory of Great Britain. The Ladoga and Onega lakes together contain as much fresh water as all the rivers of the European part of the country. But the state of Lake Ladoga is assessed as a crisis. Significant damage to the lake was caused by the Priozersk Pulp and Paper Mill. Domestic and industrial effluents enter the lake, there is an increased content of phosphorus, hydrogen sulfide, and nitrates.

Lake Erie is part of the Great Lakes system of the United States (area 52,7 thousand km2, depth up to 64 m). This lake is one example of the destruction of a large ecosystem by human activity. In the XNUMXth century the shores of the lake were occupied by forests, prairies and wetlands. By the middle of the second half of the XIX century. where they were replaced by agricultural land.

The large size of the lake symbolized the inviolability of nature. As a result, people did not take any measures to limit the impact on the reservoir and its catchment area. In addition to agricultural land, industrial enterprises, fisheries, and large cities are located around the lake. By the 1970s, the amount of substances dissolved in water had increased to 183 mg/l, and the content of nitrogen and phosphorus had tripled. The number of algae has sharply increased (15-20 times). In general, the diversity of fish has decreased. The most valuable of them have disappeared. As a result of pollution, the lake began to turn into a stinking cesspool very intensively. The biological balance of Lake Erie is broken.

54. The concept of sustainable development |

Under sustainable understand a development in which humanity can meet its needs without compromising the ability of future generations to also meet their needs.

The concept is based on the assertion that the environment and socio-economic development cannot be considered as isolated areas. Therefore, only in a world with a healthy socio-economic environment can there be a healthy environment. The Program of Action that was adopted at the World Conference in Rio de Janeiro (1992) noted "that in a world where there is so much need and where the environment is deteriorating, a healthy society and economy is impossible." While this does not mean that economic development has to stop, it can take "a different path by not being so aggressive to the environment."

At the same time, environmental problems, such as climate change and desertification, will have to be prevented. The concept also involves the development of environmental education, the work of various environmental associations, etc. It is supposed to solve other problems that are indirectly related to environmental: the development of industrial and agricultural technologies, the fight against poverty, changes in consumption patterns, the development of sustainable settlements and other issues. They are grouped into four sections of the Program of Action. A Statement and two Concepts were also adopted, which deal with such fundamental problems as climate change prevention and conservation of forests, conservation of biological diversity. Perhaps, these documents for the first time at a high level emphasized the role of the bioecological element in solving the problems of preserving the environment.

Having proclaimed the concept of sustainable development, the UN conference called on the governments of the world to adopt national concepts of sustainable development. In accordance with this, the Decree of the President of the Russian Federation of April 1, 1996 "On the concept of the transition of the Russian Federation to sustainable development" was issued. The "Concept of the Russian Federation's transition to sustainable development" presented by the Government of the Russian Federation was approved. The documents outline the main directions for the implementation of the state environmental policy in Russia. They include measures to ensure environmental safety, protect the environment, improve disturbed ecosystems and participate in solving global environmental problems.

55. The concept of the noosphere in the modern sense

V. I. Vernadsky with the concept "noosphere" linked the stage of development of the biosphere, when a person acts as a determining geological force.

Currently, various interpretations of the concept of "noosphere" are used. Some believe that the essence of the noosphere is manifested in the current environmental situation associated with human activity. Others argue that the noosphere should be understood as such a period in the development of the biosphere, when a person takes control of its processes, etc.

Modern views about the noosphere are presented mainly by statements N. N. Moiseeva in the following provisions.

1. The noosphere is inevitably preceded by a long pre-noosphere period, during which humanity must comprehend the laws of the existence of the biosphere, and find its place in the biospheric processes. This is the modern period.

2. In the pre-noospheric period, people should follow the principle "do no harm" Figuratively comparing humanity with a ship, N. N. Moiseev suggests that at the first transitional stage, his crew should behave in such a way as to keep the ship afloat, not stumble on reefs and not drown. And only having solved the tasks of the first stage, one should proceed to the second: how to bring the ship to the cherished goal - the noosphere, understanding by it the co-evolutionary (joint) path of development of man and nature, the refusal to use force in relation to the biosphere. At the same time, the solution of a task of paramount importance falls on humanity - the mind must take responsibility for the fate of the planet, which life took upon itself billions of years ago and successfully carried out before the appearance of man on the arena as a powerful biological and geological force.

3. An indispensable condition for the noospherization of all processes of human life is organizational measures. In particular, the creation of international ecological or noospheric institutions (perhaps within the framework of existing ones, but with clear coordination of actions) and the development of international environmental law. On the basis of the latter, environmentally sound decisions should be made, primarily following the recommendations of these institutions. These decisions are binding on all members (states) of the community.

You can not do without established very strict prohibitions on environmental issues, imperatives. Their task is to mitigate inevitable upheavals and conflicts on the way to finding difficult and not always unambiguous solutions.

56. Ecological priorities of the modern world

The solution of global environmental problems is impossible without the combined efforts of the entire world community.

Relevant are proposals aimed at the formation of new moral principles. For example, the rejection of only economic priorities in assessing different types of people's activities. When assessing the level of development of the state and its well-being, it is also proposed to use indicators such as measures to protect against air and water pollution, the completeness of the use of natural resources, as well as other criteria characterizing the quality of the environment. Thus, instead of gross domestic product (GDP) and per capita income, the UN recommends using the Human Development Index (HDI), as well as the index of sustainable economic well-being (SWEI). These indices directly or indirectly take into account the quality of life determined by the natural and social environment. For example, the Human Development Index should take into account the level of education, average life expectancy of people, the level of resource use for ensuring the well-being of people, etc. According to these criteria, countries with high per capita incomes may have a low Human Development Index Much attention is paid to finding ways to reduce carbon emissions in atmosphere. Over the next 30 years, carbon input into the atmosphere from technogenic sources should be reduced from 6 billion to 2 billion tons per year. Energy production should be provided mainly by non-carbon energy carriers (wind, sun, geothermal heat, etc.).

In the same context, it is necessary to consider proposals to introduce a tax on environmental pollution as a means of combating harmful emissions into the atmosphere. This tax is intended to increase the use of low-carbon and carbon-free energy sources.

It is also proposed to reduce the consumption of products by developed countries, especially meat food, and transfer it to developing countries, as well as increase in the diet of plant foods. This will solve the environmental aspects of the food problem.

Saving natural resources and reducing environmental impact can also be achieved through a more complete use of resources at the stage of their extraction and processing and by saving products of resource processing.

Great opportunities for energy and resource savings lie in the transition to knowledge-intensive technologies. This is primarily computerization, a decrease in paper production, new means of accumulating and storing information, etc.

Author: Zubanova S.G.

We recommend interesting articles Section Lecture notes, cheat sheets:

▪ Logistics. Lecture notes

▪ Sociology. Crib

▪ Financial right. Crib

See other articles Section Lecture notes, cheat sheets.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Artificial leather for touch emulation 15.04.2024

In a modern technology world where distance is becoming increasingly commonplace, maintaining connection and a sense of closeness is important. Recent developments in artificial skin by German scientists from Saarland University represent a new era in virtual interactions. German researchers from Saarland University have developed ultra-thin films that can transmit the sensation of touch over a distance. This cutting-edge technology provides new opportunities for virtual communication, especially for those who find themselves far from their loved ones. The ultra-thin films developed by the researchers, just 50 micrometers thick, can be integrated into textiles and worn like a second skin. These films act as sensors that recognize tactile signals from mom or dad, and as actuators that transmit these movements to the baby. Parents' touch to the fabric activates sensors that react to pressure and deform the ultra-thin film. This ... >>

Petgugu Global cat litter 15.04.2024

Taking care of pets can often be a challenge, especially when it comes to keeping your home clean. A new interesting solution from the Petgugu Global startup has been presented, which will make life easier for cat owners and help them keep their home perfectly clean and tidy. Startup Petgugu Global has unveiled a unique cat toilet that can automatically flush feces, keeping your home clean and fresh. This innovative device is equipped with various smart sensors that monitor your pet's toilet activity and activate to automatically clean after use. The device connects to the sewer system and ensures efficient waste removal without the need for intervention from the owner. Additionally, the toilet has a large flushable storage capacity, making it ideal for multi-cat households. The Petgugu cat litter bowl is designed for use with water-soluble litters and offers a range of additional ... >>

The attractiveness of caring men 14.04.2024

The stereotype that women prefer "bad boys" has long been widespread. However, recent research conducted by British scientists from Monash University offers a new perspective on this issue. They looked at how women responded to men's emotional responsibility and willingness to help others. The study's findings could change our understanding of what makes men attractive to women. A study conducted by scientists from Monash University leads to new findings about men's attractiveness to women. In the experiment, women were shown photographs of men with brief stories about their behavior in various situations, including their reaction to an encounter with a homeless person. Some of the men ignored the homeless man, while others helped him, such as buying him food. A study found that men who showed empathy and kindness were more attractive to women compared to men who showed empathy and kindness. ... >>

Random news from the Archive

Impregnation against fire 01.05.2003

For those who "work" with fire, special non-combustible clothing is very necessary. Impregnations for fabrics are already being used to protect them from fire.

Scientists from the Institute of Chemistry of Solutions (Ivanovo) came up with new polymeric flame retardants based on nitrogen-containing derivatives of alkyl phosphoric acid. The main difference between these substances and those already known is that they slow down the flame, actively participating in the combustion process itself.

The result of ongoing chemical reactions is a carbon residue that prevents air from reaching the material - and the fire recedes. In addition, the new moderators and their combustion products are non-toxic, all reactions proceed without the release of harmful substances. Fabrics and other materials impregnated with solutions of such retarders become resistant to burning, destruction of fibers, smoldering - and this is a very important quality for overalls.

Any flammable materials can be treated with similar compounds: wood, wallpaper, linoleum, furniture upholstery, building, finishing, paint and varnish materials.

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Biographies of great scientists. Article selection

▪ article The essence and nature of manifestations of riots. Basics of safe life

▪ article Which mammals are able to completely regenerate the skin at the site of wounds? Detailed answer

▪ Article Warehouse Manager. Job description

▪ article High frequency signal generator. Encyclopedia of radio electronics and electrical engineering

▪ article Conductive compositions. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews