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Ministry of Education and Scienceyouth and sports of Ukraine

NTU "KhPI"

Department of Labor and Environment

abstract

on the topic: "Ecological pyramids"

Completed: Art. gr. MT-30b

Mazanova Daria

Checked by Prof. Dreval A. N.

Harkov town

Introduction

1. Pyramids of numbers

2. Pyramids of biomass

3. Pyramids of energy

Conclusion

Bibliography

Introduction

The ecological pyramid is a graphic representation of the relationship between producers and consumers of all levels (herbivores, predators, species that feed on other predators) in an ecosystem. The effect of pyramids in the form of graphic models was developed in 1927 by C. Elton.

The rule of the ecological pyramid is that the amount of plant matter that serves as the basis of the food chain is about 10 times greater than the mass of herbivorous animals, and each subsequent food level also has a mass of 10 times less. This rule is known as the Lindemann rule or the 10% rule.

A chain of interconnected species that sequentially extract organic matter and energy from the original food substance. Each previous link in the food chain is food for the next link.

Here is a simple example of an ecological pyramid:

Let one person during the year can be fed with 300 trout. For their food, 90 thousand frog tadpoles are required. To feed these tadpoles, 27,000,000 insects are needed, which consume 1,000 tons of grass per year. If a person eats plant foods, then all the intermediate steps of the pyramid can be thrown out and then 1,000 tons of plant biomass can feed 1,000 times more people.

1. pyramidsnumbers

To study the relationships between organisms in an ecosystem and to graphically represent these relationships, it is more convenient to use ecological pyramids rather than food web diagrams. In this case, the number of different organisms in a given territory is first calculated, grouping them according to trophic levels.

After such calculations, it becomes obvious that the number of animals progressively decreases during the transition from the second trophic level to the next. The number of plants of the first trophic level also often exceeds the number of animals that make up the second level. This can be displayed as a pyramid of numbers.

For convenience, the number of organisms at a given trophic level can be represented as a rectangle, the length (or area) of which is proportional to the number of organisms living in a given area (or in a given volume, if it is an aquatic ecosystem).

2. pyramidsbiomass

The inconvenience associated with the use of population pyramids can be avoided by constructing biomass pyramids, which take into account the total mass of organisms (biomass) of each trophic level.

Determination of biomass includes not only counting the number, but also weighing individual individuals, so this is a more laborious process, requiring more time and special equipment.

Thus, the rectangles in the biomass pyramids represent the mass of organisms of each trophic level per unit area or volume.

When sampling, in other words, the so-called growing biomass, or standing crop, is always determined at a given point in time. It is important to understand that this value does not contain any information about the rate of biomass formation (productivity) or its consumption; Otherwise, errors may occur for two reasons:

1. If the rate of biomass consumption (loss due to eating) approximately corresponds to the rate of its formation, then the standing crop does not necessarily indicate productivity, i.e., the amount of energy and matter transferred from one trophic level to another over a given period of time, for example in a year.

Thus, on a fertile, intensively used pasture, the yield of grasses on the vine can be lower, and productivity is higher than on a less fertile, but little used for grazing.

2. A small-sized producer, such as algae, is characterized by a high rate of renewal, i.e., a high rate of growth and reproduction, balanced by their intensive consumption by other organisms as food and natural death.

Thus, although standing biomass may be small compared to large producers (eg trees), productivity may not be less because trees accumulate biomass over a long period of time.

In other words, phytoplankton with the same productivity as a tree will have a much lower biomass, although it could support the same mass of animals.

In general, populations of large and long-lived plants and animals have a slower rate of renewal compared to small and short-lived ones, and accumulate matter and energy for a longer time.

Zooplankton have a higher biomass than the phytoplankton they feed on. This is typical for plankton communities in lakes and seas at certain times of the year; phytoplankton biomass exceeds zooplankton biomass during the spring "bloom", but in other periods the reverse ratio is possible. Such apparent anomalies can be avoided by using pyramids of energy.

3. pyramidsenergy

ecosystem population biomass

Organisms in an ecosystem are linked by the commonality of energy and nutrients. The entire ecosystem can be likened to a single mechanism that consumes energy and nutrients to do work. Nutrients originally come from the abiotic component of the system, to which they eventually return either as waste products or after the death and destruction of organisms. Thus, nutrient cycling occurs in the ecosystem, in which both living and non-living components participate. The driving force behind these cycles is, ultimately, the energy of the Sun. Photosynthetic organisms directly use the energy of sunlight and then transfer it to other representatives of the biotic component.

The result is a flow of energy and nutrients through the ecosystem. Energy can exist in various interconvertible forms such as mechanical, chemical, thermal and electrical energy. The transition from one form to another is called the transformation of energy. Unlike the cyclical flow of matter in an ecosystem, the flow of energy is like a one-way street. Ecosystems receive energy from the Sun and, gradually changing from one form to another, it is dissipated in the form of heat, being lost in endless outer space.

It should also be noted that the climatic factors of the abiotic component, such as temperature, atmospheric movement, evaporation and precipitation, are also regulated by the influx of solar energy. Thus, all living organisms are energy converters, and every time energy is converted, part of it is lost in the form of heat. Eventually, all the energy that enters the biotic component of the ecosystem is dissipated as heat. In 1942, R. Lindemann formulated the law of the pyramid of energies, or the law (rule) of 10%, according to which from one trophic level of the ecological pyramid goes to another, higher level (along the "ladder": producer consumer decomposer) on average about 10 % of the energy received at the previous level of the ecological pyramid.

The reverse flow associated with the consumption of substances and the energy produced by the upper level of the ecological pyramid to its lower levels, for example, from animals to plants, is much weaker than no more than 0.5% (even 0.25%) of its total flow, and therefore we can talk about the cycle there is no energy in the biocenosis. If energy is lost tenfold during the transition to a higher level of the ecological pyramid, then the accumulation of a number of substances, including toxic and radioactive ones, increases in approximately the same proportion.

This fact is fixed in the biological amplification rule. It is true for all cenoses. With a constant energy flow in the food web or chain, smaller terrestrial organisms with a high specific metabolism create relatively less biomass than large ones.

Therefore, due to anthropogenic disturbance of nature, the “average” individual living on land is being crushed, large animals and birds are exterminated, in general, all large representatives of the plant and animal kingdom are becoming more and more rarities. This must inevitably lead to a general decrease in the relative productivity of terrestrial organisms and thermodynamic discord in biosystems, including communities and biocenoses.

The disappearance of species composed of large individuals changes the material-energy structure of cenoses. Since the energy flow passing through the biocenosis and the ecosystem as a whole practically does not change (otherwise there would be a change in the type of cenosis), the mechanisms of biocenotic, or ecological, duplication are turned on: organisms of the same trophic group and the level of the ecological pyramid naturally replace each other. Moreover, a small species takes the place of a large one, an evolutionarily lower organized one displaces a more highly organized one, a more genetically mobile one replaces a less genetically variable one. So, when ungulates are exterminated in the steppe, they are replaced by rodents, and in some cases by herbivorous insects.

In other words, it is in the anthropogenic disruption of the energy balance of natural steppe ecosystems that one of the reasons for the increased frequency of locust invasions should be sought. In the absence of predators on the watersheds of South Sakhalin, in the bamboo forests, their role is played by the gray rat.

Perhaps this is the same mechanism for the emergence of new human infectious diseases. In some cases, a completely new ecological niche appears, while in others, the fight against diseases and the destruction of their pathogens frees up such a niche in human populations. Even 13 years before the discovery of HIV, the likelihood of a “flu-like disease with a high lethality” was predicted.

Conclusion

Obviously, systems that contradict natural principles and laws are unstable. Attempts to preserve them are becoming increasingly costly and complex, and are doomed to fail anyway.

Studying the laws of functioning of ecosystems, we are dealing with the flow of energy passing through a particular ecosystem. The rate of accumulation of energy in the form of organic matter that can be used as food is an important parameter, since it determines the total energy flow through the biotic component of the ecosystem, and hence the number (biomass) of animal organisms that can exist in the ecosystem.

"Harvesting" means the removal from the ecosystem of those organisms or parts thereof that are used for food (or for other purposes). At the same time, it is desirable that the ecosystem produce products suitable for food in the most efficient way. Rational nature management is the only way out of the situation.

The overall goal of natural resource management is to select the best, or optimal, ways to exploit natural and artificial (eg, in agriculture) ecosystems. Moreover, exploitation means not only harvesting, but also the impact of certain types of economic activity on the conditions for the existence of natural biogeocenoses. Therefore, the rational use of natural resources implies the creation of a balanced agricultural production that does not deplete soil and water resources and does not pollute land and food; preservation of natural landscapes and ensuring the cleanliness of the environment, maintaining the normal functioning of ecosystems and their complexes, maintaining the biological diversity of natural communities on the planet.

Listliterature

1. Reimers N. F. Ecology. M., 1994.

2. Reimers N. F. Popular biological dictionary.

3. Nebel B. Environmental Science: How the World Works. In 2 vols. M.: Mir, 1993.

4. M. D. Goldfein, N. V. Kozhevnikov, et al., Problems of Life in the Environment.

5. Revvel P., Revvel Ch. Environment of our habitat. M., 1994.

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Ministry of Education and Science of the Russian Federation

National Research

Irkutsk State Technical University

Correspondence-evening faculty

Department of General Educational Disciplines

Ecology test

completed by: Yakovlev V.Ya

Record book number: 13150837

group: EPbz-13-2

Irkutsk 2015

1. Give the concept of an environmental factor. Classification of environmental factors

2. Ecological pyramids and their characteristics

3. What is called biological pollution of the environment?

4. What are the types of liability of officials for environmental violations?

Bibliography

1. Give the concept of an environmental factor. Classification of environmental factors

The habitat is that part of nature that surrounds a living organism and with which it directly interacts. The components and properties of the environment are diverse and changeable. Any living being lives in a complex changing world, constantly adapting to it and regulating its life activity in accordance with its changes.

Separate properties or parts of the environment that affect organisms are called environmental factors. Environmental factors are diverse. They may be necessary or, conversely, harmful to living beings, promote or hinder their survival and reproduction. Environmental factors have a different nature and specificity of action.

Abiotic factors - temperature, light, radioactive radiation, pressure, air humidity, salt composition of water, wind, currents, terrain - these are all properties of inanimate nature that directly or indirectly affect living organisms. Among them are distinguished:

Physical factors - such factors, the source of which is a physical state or phenomenon (for example, temperature, pressure, humidity, air movement, etc.).

Chemical factors - such factors that are due to the chemical composition of the environment (water salinity, oxygen content in the air, etc.).

Edaphic factors (soil) - a set of chemical, physical, mechanical properties of soils and rocks that affect both the organisms for which they are the habitat and the root system of plants (humidity, soil structure, content of nutrients, etc.) .

Biotic factors are all forms of influence of living beings on each other. Each organism constantly experiences the direct or indirect influence of others, enters into contact with representatives of its own species and other species - plants, animals, microorganisms - depends on them and itself has an impact on them. The surrounding organic world is an integral part of the environment of every living being.

Anthropogenic factors are all forms of activity of human society that lead to a change in nature, as the habitat of other species, or directly affect their lives. In the course of human history, the development of hunting first, and then agriculture, industry, and transport has greatly changed the nature of our planet. The significance of anthropogenic impacts on the entire living world of the Earth continues to grow rapidly.

The following groups of anthropogenic factors are distinguished:

Change in the structure of the earth's surface;

Changes in the composition of the biosphere, circulation and balance of its constituent substances;

Changes in the energy and heat balance of individual sections and regions;

Changes made to the biota.

The conditions of existence are a set of elements of the environment necessary for the organism, with which it is in inseparable unity and without which it cannot exist. Elements of the environment, necessary for the body or adversely affecting it, are called environmental factors. In nature, these factors do not act in isolation from each other, but in the form of a complex complex. The complex of environmental factors, without which the organism cannot exist, is the conditions for the existence of this organism.

All adaptations of organisms to existence in various conditions have developed historically. As a result, groupings of plants and animals specific to each geographical area were formed.

Environmental factors:

Elementary - light, heat, moisture, food, and so on;

Complex;

Anthropogenic;

The influence of environmental factors on living organisms is characterized by certain quantitative and qualitative patterns. The German agricultural chemist J. Liebig, observing the effect of chemical fertilizers on plants, found that limiting the dose of any of them leads to growth retardation. These observations allowed the scientist to formulate a rule that is called the law of the minimum (1840).

2. Ecological pyramids and their characteristics

An ecological pyramid is a graphic representation of the relationship between producers and consumers of all levels (herbivores, predators; species that feed on other predators) in an ecosystem.

The American zoologist Charles Elton proposed in 1927 to schematically depict these relationships.

In a schematic representation, each level is shown as a rectangle, the length or area of \u200b\u200bwhich corresponds to the numerical values \u200b\u200bof the food chain link (Elton's pyramid), their mass or energy. Rectangles arranged in a certain sequence create pyramids of various shapes.

The base of the pyramid is the first trophic level - the level of producers, the subsequent floors of the pyramid are formed by the next levels of the food chain - consumers of various orders. The height of all blocks in the pyramid is the same, and the length is proportional to the number, biomass or energy at the corresponding level.

Ecological pyramids are distinguished depending on the indicators on the basis of which the pyramid is built. At the same time, for all the pyramids, the basic rule is established, according to which in any ecosystem there are more plants than animals, herbivores than carnivores, insects than birds.

Based on the rule of the ecological pyramid, it is possible to determine or calculate the quantitative ratios of different plant and animal species in natural and artificially created ecological systems. For example, 1 kg of the mass of a sea animal (seal, dolphin) needs 10 kg of eaten fish, and these 10 kg already need 100 kg of their food - aquatic invertebrates, which, in turn, need to eat 1000 kg of algae and bacteria to form such a mass. In this case, the ecological pyramid will be stable.

However, as you know, there are exceptions to every rule, which will be considered in each type of ecological pyramids.

Types of ecological pyramids

Pyramids of numbers - at each level, the number of individual organisms is postponed

The pyramid of numbers reflects a clear pattern discovered by Elton: the number of individuals that make up a sequential series of links from producers to consumers is steadily decreasing (Fig. 3).

For example, to feed one wolf, you need at least a few hares that he could hunt; to feed these hares, you need a fairly large number of various plants. In this case, the pyramid will look like a triangle with a wide base tapering upwards.

However, this form of a pyramid of numbers is not typical for all ecosystems. Sometimes they can be reversed, or inverted. This applies to forest food chains, when trees serve as producers, and insects as primary consumers. In this case, the level of primary consumers is numerically richer than the level of producers (a large number of insects feed on one tree), so the pyramids of numbers are the least informative and least indicative, i.e. the number of organisms of the same trophic level largely depends on their size.

Biomass pyramids - characterizes the total dry or wet mass of organisms at a given trophic level, for example, in units of mass per unit area - g / m2, kg / ha, t / km2 or per volume - g / m3 (Fig. 4)

Usually, in terrestrial biocenoses, the total mass of producers is greater than each subsequent link. In turn, the total mass of first-order consumers is greater than second-order consumers, and so on.

In this case (if the organisms do not differ too much in size), the pyramid will also look like a triangle with a wide base tapering upwards. However, there are significant exceptions to this rule. For example, in the seas, the biomass of herbivorous zooplankton is significantly (sometimes 2-3 times) greater than the biomass of phytoplankton, which is represented mainly by unicellular algae. This is explained by the fact that algae are very quickly eaten away by zooplankton, but the very high rate of division of their cells protects them from complete eating.

In general, terrestrial biogeocenoses, where producers are large and live relatively long, are characterized by relatively stable pyramids with a wide base. In aquatic ecosystems, where producers are small in size and have short life cycles, the biomass pyramid can be reversed or inverted (pointed downwards). So, in lakes and seas, the mass of plants exceeds the mass of consumers only during the flowering period (spring), and in the rest of the year the situation may be reversed.

Pyramids of numbers and biomass reflect the statics of the system, i.e., they characterize the number or biomass of organisms in a certain period of time. They do not provide complete information about the trophic structure of the ecosystem, although they allow solving a number of practical problems, especially those related to maintaining the stability of ecosystems.

The pyramid of numbers makes it possible, for example, to calculate the allowable value of catching fish or shooting animals during the hunting period without consequences for their normal reproduction.

Pyramids of energy - shows the amount of energy flow or productivity at successive levels (Fig. 5).

In contrast to the pyramids of numbers and biomass, which reflect the statics of the system (the number of organisms at a given moment), the pyramid of energy, reflecting the picture of the speed of passage of a mass of food (amount of energy) through each trophic level of the food chain, gives the most complete picture of the functional organization of communities.

The shape of this pyramid is not affected by changes in the size and intensity of metabolism of individuals, and if all sources of energy are taken into account, then the pyramid will always have a typical appearance with a wide base and a tapering top. When building a pyramid of energy, a rectangle is often added to its base, showing the influx of solar energy.

In 1942, the American ecologist R. Lindeman formulated the law of the pyramid of energies (the law of 10 percent), according to which, on average, about 10% of the energy received by the previous level of the ecological pyramid passes from one trophic level through food chains to another trophic level. The rest of the energy is lost in the form of thermal radiation, movement, etc. Organisms, as a result of metabolic processes, lose about 90% of all the energy that is expended to maintain their vital activity in each link of the food chain.

If a hare ate 10 kg of plant matter, then its own weight could increase by 1 kg. A fox or a wolf, eating 1 kg of hare, increases its mass by only 100 g. In woody plants, this proportion is much lower due to the fact that wood is poorly absorbed by organisms. For grasses and algae, this value is much higher, since they do not have hard-to-digest tissues. However, the general regularity of the process of energy transfer remains: much less energy passes through the upper trophic levels than through the lower ones.

Consider the transformation of energy in an ecosystem using the example of a simple pasture trophic chain, in which there are only three trophic levels.

level - herbaceous plants,

level - herbivorous mammals, for example, hares

level - predatory mammals, for example, foxes

Nutrients are created in the process of photosynthesis by plants, which from inorganic substances (water, carbon dioxide, mineral salts, etc.) using the energy of sunlight form organic substances and oxygen, as well as ATP. Part of the electromagnetic energy of solar radiation is then converted into the energy of chemical bonds of synthesized organic substances.

All organic matter created during photosynthesis is called gross primary production (GPP). Part of the energy of gross primary production is spent on respiration, resulting in the formation of net primary production (NPP), which is the very substance that enters the second trophic level and is used by hares.

Let the runway be 200 conventional units of energy, and the costs of plants for respiration (R) be 50%, i.e. 100 conventional units of energy. Then the net primary production will be equal to: NPP = WPP - R (100 = 200 - 100), i.e. at the second trophic level, hares will receive 100 conventional units of energy.

However, for various reasons, hares are able to consume only a certain proportion of NPP (otherwise, resources for the development of living matter would disappear), but a significant part of it, in the form of dead organic residues (underground parts of plants, hard wood of stems, branches, etc. .) is not able to be eaten by hares. It enters detritus food chains and (or) is decomposed by decomposers (F). The other part goes to building new cells (population size, growth of hares - P) and ensuring energy metabolism or respiration (R).

In this case, according to the balance approach, the balance equation of energy consumption (C) will look like this: C = P + R + F, i.e. The energy received at the second trophic level will be spent, according to Lindemann's law, for population growth - P - 10%, the remaining 90% will be spent on breathing and removing undigested food.

Thus, in ecosystems with an increase in the trophic level, there is a rapid decrease in the energy accumulated in the bodies of living organisms. From this it is clear why each subsequent level will always be less than the previous one and why food chains usually cannot have more than 3-5 (rarely 6) links, and ecological pyramids cannot consist of a large number of floors: to the final link of the food chain in the same way as to the top floor of the ecological pyramid will receive so little energy that it will not be enough in case of an increase in the number of organisms.

Such a sequence and subordination of groups of organisms connected in the form of trophic levels is the flow of matter and energy in the biogeocenosis, the basis of its functional organization.

3. What is called biological pollution of the environment?

Ecology is the theoretical basis of rational nature management, it plays a leading role in developing a strategy for the relationship between nature and human society. Industrial ecology considers the violation of natural balance as a result of economic activity. At the same time, environmental pollution is the most significant in its consequences. The term "environment" is commonly understood as everything that directly or indirectly affects human life and activities.

The role of yeasts in natural ecosystems should also be assessed in a new way. For example, long considered harmless commensals, many epiphytic yeasts that abundantly seed the green parts of plants may not be so “innocent” if we consider that they represent only a haploid stage in the life cycle of organisms closely related to phytopathogenic smut or rust fungi. Conversely, yeast pathogenic for humans, causing dangerous and intractable diseases - candidiasis and cryptococcosis - in nature have a saprotrophic stage and are easily isolated from dead organic substrates. It can be seen from these examples that to understand the ecological functions of yeast, it is necessary to study the complete life cycles of each species. Autochthonous soil yeasts with specific functions important for the formation of soil structure have also been found. Inexhaustible in variety and connection of yeast with animals, especially with invertebrates.

Atmospheric pollution can be associated with natural processes: volcanic eruptions, dust storms, forest fires.

In addition, the atmosphere is polluted as a result of human production activities.

Sources of air pollution are smoke emissions from industrial enterprises. Emissions are organized and unorganized. Emissions coming from the pipes of industrial enterprises are specially directed and organized. Before entering the pipe, they pass through treatment facilities, in which some of the harmful substances are absorbed. From windows, doors, ventilation openings of industrial buildings, fugitive emissions enter the atmosphere. The main pollutants in emissions are particulate matter (dust, soot) and gaseous substances (carbon monoxide, sulfur dioxide, nitrogen oxides).

The selection and identification of microorganisms with useful properties for a certain production is a very important work from an ecological point of view, since their use can intensify the process or more fully utilize the components of the substrate.

The essence of the methods of bioremediation, biological treatment, bioprocessing and biomodification is the use of various biological agents in the environment, primarily microorganisms. In this case, it is possible to use both microorganisms obtained by traditional breeding methods and those created using genetic engineering, as well as transgenic plants that can affect the biological balance of natural ecosystems.

The environment may contain industrial strains of various microorganisms - producers of the biosynthesis of certain substances, as well as products of their metabolism, which act as a biological pollution factor. Its action may be to change the structure of biocenoses. Indirect effects of biological pollution are manifested, for example, when antibiotics and other medicines are used in medicine, when strains of microorganisms appear that are resistant to their action and dangerous for the human internal environment; in the form of complications when using vaccines and sera containing impurities of substances of biological origin; as an allergenic and genetic effect of microorganisms and their metabolic products.

Biotechnological large-scale productions are a source of emission of bioaerosols containing cells of non-pathogenic microorganisms, as well as products of their metabolism. The main sources of bioaerosols containing living cells of microorganisms are the stages of fermentation and separation, and of inactivated cells - the stage of drying. With a massive release, microbial biomass, entering the soil or a water body, changes the distribution of energy and substance flows in trophic food chains and affects the structure and function of biocenoses, reduces the activity of self-purification and, therefore, affects the global function of the biota. At the same time, it is possible to provoke the active development of certain organisms, including microorganisms of sanitary-indicative groups.

The dynamics of introduced populations and indicators of their biotechnological potential depend on the type of microorganism, the state of the soil microbial system at the time of introduction, the stage of microbial succession, and the dose of the introduced population. At the same time, the consequences of the introduction of microorganisms new to soil biocenoses can be ambiguous. Due to self-purification, not every microbial population introduced into the soil is eliminated. The nature of the population dynamics of introduced microorganisms depends on the degree of their adaptation to new conditions. Unadapted populations die, adapted ones survive.

The biological pollution factor can be defined as a set of biological components, the impact of which on humans and the environment is associated with their ability to reproduce in natural or artificial conditions, produce biologically active substances, and, if they or their metabolic products enter the environment, have adverse effects on the environment. , people, animals, plants.

Biological pollution factors (most often microbial) can be classified as follows: live microorganisms with a natural genome that do not have toxicity, saprophytes, live microorganisms with a natural genome that have infectious activity, pathogenic and opportunistic pathogens that produce toxins, live microorganisms obtained by genetic methods. engineering (genetically modified microorganisms containing foreign genes or new combinations of genes - GMMOs), infectious and other viruses, toxins of biological origin, inactivated cells of microorganisms (vaccines, dust of thermally inactivated biomass of microorganisms for feed and food purposes), metabolic products of microorganisms, organelles and organic cell compounds are the products of its fractionation.

The purpose of our work was the isolation and identification of yeast microorganisms in the laboratory of biotechnology of the Gorsky State Agrarian University, belonging to the first group of the above organisms. Since these are microorganisms with a natural genome and do not have toxicity, their impact on the environment is very organic and not significant.

Sources of microorganisms, including opportunistic and pathogenic ones, are sewage (household fecal, industrial, urban storm drains). In rural areas, faecal pollution comes from residential runoff, pastures, livestock and bird pens, and wildlife. In the process of wastewater treatment, the number of pathogenic microorganisms in them decreases. The scale of their impact on the environment is insignificant, however, since this source of microbial cell emission exists, it must be taken into account as a factor in environmental pollution.

The water used in the course of our work for the preparation of media, flushes, autoclave heating and thermostats can be treated at municipal wastewater treatment plants along with municipal wastewater in an aerobic or anaerobic manner.

Biological pollutants in terms of environmental properties differ significantly from chemical ones. In terms of chemical composition, technogenic biological pollution is identical to natural components; they are included in the natural cycle of substances and trophic food chains without accumulation in the environment.

All microbiological and virological laboratories must be equipped with a wastewater receiver, where the collected effluents must be neutralized by a chemical, physical or biological method or a combined method before being discharged into the city sewer.

4. What are the types of liability of officials for environmental violations?

Environmental and legal liability is a kind of general legal liability, but at the same time differs from other types of legal liability.

Environmental and legal responsibility is considered in three interrelated aspects:

as state coercion to fulfill the requirements prescribed by law;

as a legal relationship between the state (represented by its bodies) and offenders (who are subject to sanctions);

as a legal institution, i.e. a set of legal norms, various branches of law (land, mining, water, forest, environmental, etc.). Environmental offenses are punished in accordance with the requirements of the legislation of the Russian Federation. The ultimate goal of environmental legislation and each of its individual articles is to protect against pollution, to ensure the lawful use of the environment and its elements protected by law. The scope of environmental legislation is the environment and its individual elements. The object of the offense is an element of the environment. The requirements of the law require the establishment of a clear causal relationship between the violation and the deterioration of the environment.

The subject of environmental offenses is a person who has reached the age of 16, to whom the relevant official duties are assigned by regulatory legal acts (compliance with the rules of environmental protection, control over compliance with the rules), or any person who has reached the age of 16 who has violated the requirements of environmental legislation.

An environmental offense is characterized by the presence of three elements:

wrongful conduct;

causing environmental harm (or real threat) or violation of other legal rights and interests of the subject of environmental law;

a causal relationship between unlawful behavior and environmental damage or a real threat of causing such damage or violation of other legal rights and interests of subjects of environmental law.

Liability for environmental offenses is one of the main means of ensuring compliance with the requirements of legislation on environmental protection and the use of natural resources. The effectiveness of this tool largely depends, first of all, on state bodies authorized to apply legal liability measures to violators of environmental legislation. In accordance with Russian legislation in the field of environmental protection, officials and citizens for environmental offenses bear disciplinary, administrative, criminal, civil and material liability, and enterprises - administrative and civil liability.

Disciplinary liability arises for non-fulfillment of plans and measures for the protection of nature and the rational use of natural resources, for violation of environmental standards and other requirements of environmental legislation arising from a labor function or official position. Disciplinary responsibility is borne by officials and other guilty employees of enterprises and organizations in accordance with the regulations, charters, internal regulations and other regulations (Article 82 of the Law "On Environmental Protection"). In accordance with the Code of Labor Laws (as amended and supplemented on September 25, 1992), the following disciplinary sanctions may be applied to violators: reprimand, reprimand, severe reprimand, dismissal from work, other punishments (Article 135).

Liability is also regulated by the Labor Code of the Russian Federation (Articles 118-126). Such liability is borne by officials and other employees of the enterprise, through whose fault the enterprise incurred the costs of compensation for damage caused by an environmental offense.

The application of administrative responsibility is regulated by both environmental legislation and the RSFSR Code of Administrative Offenses of 1984 (with amendments and additions). The Law “On the Protection of the Environment” has expanded the list of elements of environmental offenses, in the commission of which guilty officials, individuals and legal entities bear administrative responsibility. Such liability arises for exceeding the maximum allowable emissions and discharges of harmful substances into the environment, failure to fulfill the obligations to conduct the state environmental review and the requirements contained in the conclusion of the environmental review, providing deliberately incorrect and unreasonable conclusions, untimely provision of information and provision of distorted information, refusal to provide timely, complete, reliable information about the state of the natural environment and the radiation situation, etc.

The specific amount of the fine is determined by the body imposing the fine, depending on the nature and type of the offense, the degree of guilt of the offender and the harm caused. Administrative fines are imposed by authorized state bodies in the field of environmental protection, sanitary and epidemiological supervision of the Russian Federation. In this case, the decision to impose a fine may be appealed to a court or arbitration court. The imposition of a fine does not release the perpetrators from the obligation to compensate for the harm caused (Article 84 of the Law “On Environmental Protection”).

In the new Criminal Code of the Russian Federation, environmental crimes are singled out in a separate chapter (Chapter 26). It provides for criminal liability for violation of environmental safety rules in the course of work, violation of the rules for storage, disposal of environmentally hazardous substances and waste, violation of safety rules when handling microbiological or other biological agents or toxins, pollution of water, atmosphere and sea, violation of legislation on continental shelf, damage to land, illegal harvesting of aquatic animals and plants, violation of the rules for the protection of fish stocks, illegal hunting, illegal felling of trees and shrubs, destruction or damage to forests.

The application of measures of disciplinary, administrative or criminal liability for environmental offenses does not release the perpetrators from the obligation to compensate for harm caused by an environmental offense. The Law "On Environmental Protection" takes the position that enterprises, organizations and citizens that cause harm to the environment, health or property of citizens, the national economy by environmental pollution, damage, destruction, damage, irrational use of natural resources, destruction of natural ecological systems and other environmental offenses are obliged to compensate it in full in accordance with applicable law (Article 86).

Civil liability in the sphere of interaction between society and nature consists mainly in imposing on the offender the obligation to compensate the injured party for property or moral damage as a result of violation of legal environmental requirements.

Responsibility for environmental offenses performs a number of main functions:

encouraging compliance with environmental law;

compensatory, aimed at compensating for losses in the natural environment, compensation for harm to human health;

preventive, which consists in punishing the person guilty of committing an environmental offense.

Environmental legislation provides for three levels of punishment: for violation; violation that caused significant damage; a violation resulting in the death of a person (serious consequences). The death of a person as a result of an environmental crime is assessed by law as negligence (committed through negligence or frivolity). The types of punishment for environmental violations can be a fine, deprivation of the right to hold certain positions, deprivation of the right to engage in certain activities, correctional labor, restriction of liberty, imprisonment.

One of the most serious environmental crimes is ecocide - the mass destruction of the flora (plant communities of the land of Russia or its individual regions) or the animal world (the totality of living organisms of all kinds of wild animals inhabiting the territory of Russia or a certain region of it), poisoning the atmosphere and water resources ( surface and ground waters that are used or can be used), as well as the commission of other actions that can cause an environmental catastrophe. The social danger of ecocide consists in the threat or causing great harm to the natural environment, the preservation of the gene pool of the people, flora and fauna.

An ecological catastrophe manifests itself in a serious violation of the ecological balance in nature, the destruction of a stable species composition of living organisms, a complete or significant reduction in their numbers, and in violation of the cycles of seasonal changes in the biotic circulation of substances and biological processes. Ecocide may be motivated by misunderstood military or state interests, the commission of actions with direct or indirect intent.

Success in establishing environmental law and order is achieved by a gradual increase in public and state influence on persistent offenders, by an optimal combination of educational, economic and legal measures.

environmental pollution offense

Bibliography

1. Akimova T.V. Ecology. Man-Economy-Biota-Environment: Textbook for university students / T.A. Akimova, V.V. Khaskin; 2nd ed., revised. and additional - M.: UNITI, 2009.- 556 p.

Akimova T.V. Ecology. Nature-Man-Technology.: A textbook for students of tech. direction and spec. universities / T.A. Akimova, A.P. Kuzmin, V.V. Haskin ..- Under the total. ed. A.P. Kuzmina. M.: UNITI-DANA, 2011.- 343 p.

Brodsky A.K. General ecology: A textbook for university students. M.: Ed. Center "Academy", 2011. - 256 p.

Voronkov N.A. Ecology: general, social, applied. Textbook for university students. M.: Agar, 2011. - 424 p.

Korobkin V.I. Ecology: Textbook for university students / V.I. Korobkin, L.V. Peredelsky. -6th ed., add. And revised. - Roston n / D: Phoenix, 2012. - 575s.

Nikolaikin N.I., Nikolaykina N.E., Melekhova O.P. Ecology. 2nd ed. Textbook for high schools. M.: Bustard, 2008. - 624 p.

Stadnitsky G.V., Rodionov A.I. Ecology: Uch. allowance for st. chemical-technological and tech. cn. universities. / Ed. V.A. Solovieva, Yu.A. Krotova. - 4th ed., corrected. - St. Petersburg: Chemistry, 2012. -238s.

Odum Yu. Ecology vol. 1.2. World, 2011.

Chernova N.M. General ecology: A textbook for students of pedagogical universities / N.M. Chernova, A.M. Bylov. - M.: Bustard, 2008.-416 p.

Ecology: A textbook for students of higher education. and avg. textbook institutions, educational according to tech. specialist. and directions / L.I. Tsvetkova, M.I. Alekseev, F.V. Karamzinov and others; under total ed. L.I. Tsvetkova. Moscow: ASBV; St. Petersburg: Himizdat, 2012. - 550 p.

Ecology. Ed. prof. V.V. Denisov. Rostov-on-D.: ICC "Mart", 2011. - 768 p.

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There are three ways of compiling ecological pyramids:

1. The pyramid of numbers reflects the numerical ratio of individuals of different trophic levels of the ecosystem. If organisms within the same or different trophic levels vary greatly in size, then the pyramid of numbers gives distorted ideas about the true ratios of trophic levels. For example, in a plankton community, the number of producers is tens and hundreds of times greater than the number of consumers, and in the forest, hundreds of thousands of consumers can feed on the organs of one tree - the producer.

2. The biomass pyramid shows the amount of living matter, or biomass, at each trophic level. In most terrestrial ecosystems, the biomass of producers, i.e., the total mass of plants, is the largest, and the biomass of organisms of each subsequent trophic level is less than the previous one. However, in some communities, the biomass of consumers of the first order is greater than the biomass of producers. For example, in the oceans, where the main producers are unicellular algae with a high reproduction rate, their annual production can exceed the biomass reserve by tens and even hundreds of times. At the same time, all the products formed by algae are so quickly involved in the food chain that the accumulation of algae biomass is small, but due to high reproduction rates, their small reserve is sufficient to maintain the rate of organic matter reproduction. In this regard, in the ocean, the biomass pyramid has an inverse relationship, i.e., “inverted”. At the highest trophic levels, the tendency to accumulate biomass prevails, since the life span of predators is long, the turnover rate of their generations, on the contrary, is low, and a significant part of the substance that enters the food chains is retained in their body.

3. The pyramid of energy reflects the amount of energy flow in the food chain. The shape of this pyramid is not affected by the size of the individuals, and will always be triangular with a wide base at the bottom, as dictated by the second law of thermodynamics. Therefore, the pyramid of energy gives the most complete and accurate idea of the functional organization of the community, of all metabolic processes in the ecosystem. If the pyramids of numbers and biomass reflect the statics of the ecosystem (the number and biomass of organisms at a given moment), then the pyramid of energy reflects the dynamics of the passage of a mass of food through the food chain. Thus, the base in the pyramids of numbers and biomass can be larger or smaller than the subsequent trophic levels (depending on the ratio of producers and consumers in different ecosystems). The pyramid of energy always narrows upwards. This is due to the fact that the energy spent on respiration is not transferred to the next trophic level and leaves the ecosystem. Therefore, each subsequent level will always be less than the previous one. In terrestrial ecosystems, a decrease in the amount of available energy is usually accompanied by a decrease in the abundance and biomass of individuals at each trophic level. Due to such large losses of energy for the construction of new tissues and the respiration of organisms, food chains cannot be long; usually they consist of 3-5 links (trophic levels).

Knowledge of the laws of ecosystem productivity, the ability to quantify the flow of energy are of great practical importance, since the products of natural and artificial communities (agroenoses) are the main source of food for mankind. Accurate calculations of the energy flow and the scale of ecosystem productivity make it possible to regulate the cycle of substances in them in such a way as to achieve the greatest yield of products necessary for humans.

Successions and their types.

The process by which communities of plant and animal species are replaced over time by other, usually more complex, communities is called ecological succession, or just succession.

Ecological succession usually continues until the community is stable and self-sustaining. Ecologists distinguish two types of ecological succession: primary and secondary.

primary succession- this is the consistent development of communities in areas devoid of soil.

Stage 1 - the emergence of a place devoid of life;

2nd stage - resettlement of the first plant and animal organisms at this place;

3rd stage - survival of organisms;

4th stage - competition and displacement of species;

5th stage - transformation of habitat by organisms, gradual stabilization of conditions and relationships.

A well-known example of primary succession is the colonization of hardened lava after a volcanic eruption or a slope after an avalanche that destroyed the entire soil profile, open-pit mining areas from which the topsoil was removed, etc. In such barren areas, primary succession from bare rock to mature forest can take hundreds to thousands of years.

secondary succession- consistent development of communities in an area in which natural vegetation has been eliminated or severely disturbed, but the soil has not been destroyed. Secondary succession begins at the site of the destroyed biocenosis (forest after a fire). Succession is fast because seeds, parts of food links are preserved in the soil, and a biocenosis is formed. If we consider succession on abandoned lands that are not used in agriculture, we can see that the former fields are quickly covered with a variety of annual plants. Seeds of tree species: pine, spruce, birch, aspen, can also get here, sometimes overcoming long distances with the help of wind or animals. In the beginning, change happens quickly. Then, as more slowly growing plants emerge, the rate of succession decreases. Birch sprouts form a dense growth that shades the soil, and even if spruce seeds germinate along with birch, its sprouts, being in very unfavorable conditions, lag far behind birch trees. The birch is called the "pioneer of the forest" as it is almost always the first to settle in disturbed lands and has a wide range of adaptability. Birches at the age of 2-3 years can reach a height of 100-120 cm, while fir-trees at the same age barely reach 10 cm. Changes also affect the animal component of the considered biocenosis. At the first stages, May-bearers, birch moths settle, then numerous birds appear: finches, warblers, warblers. Small mammals settle: shrews, moles, hedgehogs. Changing lighting conditions begin to have a positive effect on young Christmas trees, which accelerate their growth.

The stable stage of succession, when the community (biocenosis) has fully formed and is in balance with the environment, is called climax. The climax community is capable of self-regulation and can be in equilibrium for a long time.

Thus, succession occurs, in which at first a birch, then a mixed spruce-birch forest is replaced by a pure spruce forest. The natural process of changing birch forest to spruce forest lasts for more than 100 years. That is why the process of succession is sometimes called secular change.

18. Functions of living matter in the biosphere. living matter - it is the totality of living organisms (biomass of the Earth). It is an open system which is characterized by growth, reproduction, distribution, exchange of matter and energy with the external environment, accumulation of energy and its transfer in food chains. Living matter performs 5 functions:

1. Energy (the ability to absorb solar energy, convert it into the energy of chemical bonds and transfer it through food chains)

2. Gas (the ability to maintain the constancy of the gas composition of the biosphere as a result of the balance of respiration and photosynthesis)

3. Concentration (the ability of living organisms to accumulate certain elements of the environment in their body, due to which the elements were redistributed and minerals were formed)

4. Redox (the ability to change the oxidation state of elements and create a variety of compounds in nature to maintain the diversity of life)

5. Destructive (the ability to decompose dead organic matter, due to which the circulation of substances is carried out)

The water function of living matter in the biosphere is associated with the biogenic water cycle, which is of great importance in the water cycle on the planet.

Performing the listed functions, living matter adapts to the environment and adapts it to its biological (and if we are talking about a person, then also social) needs. At the same time, living matter and its habitat develop as a whole, but control over the state of the environment is carried out by living organisms.

The main process that occurs in all ecosystems is the transfer and circulation of matter or energy. However, losses are inevitable. The magnitude of these losses from level to level is what the rules of ecological pyramids reflect.

Some academic terms

The exchange of matter and energy is a directed flow in the chain of producers - consumers. Simply put, the eating of some organisms by others. At the same time, a chain or sequence of organisms is built, which, as links in the chain, are connected by the relationship "food - consumer". This sequence is called the trophic or food chain. And the links in it are trophic levels. The first level of the chain is producers (plants), because only they can form organic substances from inorganic ones. The next links are consumers (animals) of various orders. Herbivores are consumers of the 1st order, and predators that feed on herbivores will be consumers of the 2nd order. The next link in the chain will be decomposers - organisms whose food is the remains of life or the corpses of living organisms.

Graphic pyramids

The British ecologist Charles Elton (1900-1991) in 1927, based on the analysis of quantitative changes in food chains, introduced the concept of ecological pyramids into biology as a graphic illustration of the ratios in the ecosystem of producers and consumers. Elton's pyramid is depicted as a triangle divided by the number of links in the chain. Or in the form of rectangles standing on top of each other.

Patterns of the pyramid

C. Elton analyzed the number of organisms in chains and found that there are always more plants than animals. Moreover, the ratio of levels in quantitative terms is always the same - a decrease occurs at each next level, and this is an objective conclusion, which is reflected in the rules of ecological pyramids.

Elton's rule

This rule states that the number of individuals in a sequence decreases from level to level. The rules of the ecological pyramid are the quantitative ratio of the products of all levels of a particular food chain. It says that the chain level indicator will be approximately 10 times less than that of the previous level.

Given a simple example that will dot the "and". Consider the trophic chain of algae - invertebrate crustaceans - herring - dolphin. A 40 kg dolphin needs to eat 400 kg of herring to live. And in order for these 400 kilograms of fish to exist, about 4 tons of their food is needed - invertebrate crustaceans. For the formation of 4 tons of crustaceans, 40 tons of algae are already needed. This is what the rules of the ecological pyramid reflect. And only in such a ratio will this ecological structure be sustainable.

Types of ecopyramids

Based on the criterion that will be taken into account when evaluating the pyramids, there are:

Numeric.
Biomass estimates.
Energy costs.

In all cases, the rule of the ecological pyramid reflects a decrease in the main evaluation criterion by 10 times.

Number of individuals and trophic steps

In the pyramid of numbers, the number of organisms is taken into account, which is reflected in the rule of the ecological pyramid. And the example with the dolphin fully fits the description of this type of pyramids. But there are exceptions - a forest ecosystem with a chain of plants - insects. The pyramid will become inverted (a huge number of insects feeding on one tree). That is why the pyramid of numbers is considered not the most informative and indicative.

And what's left?

The biomass pyramid uses the dry (rarely wet) mass of individuals of the same level as an evaluation criterion. Units of measurement - gram / square meter, kilogram / hectare or gram / cubic meter. But even here there are exceptions. The rules of ecological pyramids, which reflect a decrease in the biomass of consumers in relation to the biomass of producers, are carried out for biocenoses, where both are large and have a long life cycle. But for water systems, the pyramid can again be inverted. For example, in the seas, the biomass of zooplankton feeding on algae is sometimes 3 times greater than the biomass of plant plankton itself. saves the high rate of reproduction of phytoplankton.

Energy flow is the most accurate indicator

Pyramids of energy show the speed of passage of food (its mass) through trophic levels. The law of the pyramid of energy was formulated by the outstanding ecologist from America Raymond Lindeman (1915-1942), after his death in 1942 he entered biology as a rule of ten percent. According to it, 10% of the energy from the previous one goes to each subsequent level, the remaining 90% are losses that go to support the body's vital functions (breathing, heat regulation).

The meaning of the pyramids

We have analyzed what the rules of ecological pyramids reflect. But why do we need this knowledge? Pyramids of numbers and biomass make it possible to solve some practical problems, since they describe the static and stable state of the system. For example, they are used in calculating the allowable values of the catch of fish or counting the number of animals for shooting, so as not to disturb the stability of the ecosystem and determine the maximum size of a particular population of individuals for a given ecosystem in its entirety. And the pyramid of energies gives a clear idea of the organization of functional communities, allows you to compare different ecosystems in terms of their productivity.

Now the reader will not be at a loss, having received a task like “describe what the rules of ecological pyramids reflect”, and boldly answer that these are the loss of matter and energy in a specific trophic chain.

1. Pyramids of numbers- at each level, the number of individual organisms is plotted.

The pyramid of numbers reflects a distinct pattern discovered by Elton: the number of individuals that make up a sequential series of links from producers to consumers is steadily decreasing (Fig. 3).

However, this form of the pyramid of numbers is not typical for all ecosystems. Sometimes they can be reversed, or inverted. This applies to forest food chains, when trees serve as producers, and insects as primary consumers. In this case, the level of primary consumers is numerically richer than the level of producers (a large number of insects feed on one tree), so the pyramids of numbers are the least informative and least indicative, i.e. the number of organisms of the same trophic level largely depends on their size.

2. biomass pyramids- characterizes the total dry or wet mass of organisms at a given trophic level, for example, in units of mass per unit area - g / m 2, kg / ha, t / km 2 or per volume - g / m 3 (Fig. 4)

3. energy pyramids- shows the magnitude of the energy flow or productivity at successive levels (Fig. 5).

Consider the transformation of energy in an ecosystem using the example of a simple pasture trophic chain, in which there are only three trophic levels.

1. Level - herbaceous plants,

2. Level - herbivorous mammals, for example, hares

3. Level - predatory mammals, for example, foxes

In this case, according to the balance approach, the balance equation of energy consumption (C) will look like this: C = P + R + F, i.e. the energy received at the second trophic level will be spent, according to Lindemann's law, for population growth - P - 10%, the remaining 90% will be spent on breathing and removing undigested food.

Such a sequence and subordination of groups of organisms connected in the form of trophic levels is the flow of matter and energy in the biogeocenosis, the basis of its functional organization.

The most important type of relationship between organisms in a biocenosis, which actually form its structure, is the food connections of a predator and prey: some are eaters, others are eaten. At the same time, all organisms, living and dead, are food for other organisms: a hare eats grass, a fox and a wolf hunt hares, birds of prey (hawks, eagles, etc.) are able to drag and eat both a fox cub and a wolf cub. Dead plants, hares, foxes, wolves, birds become food for detritivores (decomposers or otherwise destructors).

A food chain is a sequence of organisms in which each eats or decomposes the other. It represents the path of a unidirectional flow of a small part of the highly efficient solar energy absorbed during photosynthesis, which came to Earth, moving through living organisms. Ultimately, this circuit is returned to the natural environment in the form of low-efficiency thermal energy. Nutrients also move along it from producers to consumers and then to decomposers, and then back to producers.

Each link in the food chain is called a trophic level. The first trophic level is occupied by autotrophs, otherwise referred to as primary producers. Organisms of the second trophic level are called primary consumers, the third - secondary consumers, etc. Usually there are four or five trophic levels and rarely more than six (Fig. 1).

There are two main types of food chains - grazing (or "eating") and detrital (or "decaying").

Rice. 1. Food chains of biocenosis according to N.F. Reimers: generalized (a) and real (b)

The arrows in Figure 1 show the direction of energy movement, and the numbers show the relative amount of energy coming to the trophic level.

In grazing food chains, the first trophic level is occupied by green plants, the second by grazing animals (the term "grassland" covers all organisms that feed on plants), and the third by predators.

So, pasture food chains are:

PLANT MATERIAL (e.g. nectar) => FLY => SPIDER =>

=> SHREDDER => OWL

ROSE BUSH JUICE => APHIDS => LADYBUG => SPIDER =>

=> INSECTIVORUS BIRD => BIRD OF PREY.

The detrital food chain begins with detritus according to the scheme:

DETRIT-> DETRITOPHY -> PREDATOR

Typical detrital food chains are:

FOREST LITTER => EARTHWORM => BLACKDRUS =>

=> SPARROW HAWK

DEAD ANIMAL \u003d\u003e CARRIER FLY LARVIES \u003d\u003e GRASS FROG \u003d\u003e ORDINARY SNAIL.

The concept of food chains allows us to further trace the cycle of chemical elements in nature, although simple food chains like those depicted earlier, where each organism is represented as feeding on organisms of only one type, are rarely found in nature.

Real food relationships are much more complicated, because an animal can feed on organisms of different types that are part of the same food chain or different chains, which is especially characteristic of predators (consumers) of higher trophic levels. The relationship between pasture and detritus food chains is illustrated by the energy flow model proposed by Yu. Odum (Fig. 2).

Omnivorous animals (in particular, humans) feed on both consumers and producers. Thus, in nature, food chains intertwine, form food (trophic) networks.

Rice. 2. Scheme of pasture and detrital food chains (according to Yu. Odum)

Lindemann's rule (10%)

The through flow of energy, passing through the trophic levels of the biocenosis, is gradually extinguished. In 1942, R. Lindemann formulated the law of the pyramid of energies, or the law (rule) of 10%, according to which from one trophic level of the ecological pyramid it moves to another, higher level (along the "ladder": producer - consumer - decomposer) on average about 10% of the energy received at the previous level of the ecological pyramid. The reverse flow associated with the consumption of substances and the energy produced by the upper level of the ecological pyramid of energy by its lower levels, for example, from animals to plants, is much weaker - no more than 0.5% (even 0.25%) of its total flow, and therefore we can say about the cycle of energy in the biocenosis is not necessary.

If energy is lost tenfold during the transition to a higher level of the ecological pyramid, then the accumulation of a number of substances, including toxic and radioactive ones, increases in approximately the same proportion. This fact is fixed in the biological amplification rule. It is true for all cenoses. In aquatic biocenoses, the accumulation of many toxic substances, including organochlorine pesticides, correlates with the mass of fats (lipids), i.e. clearly has an energy background.

Mangroves

Food chains can be divided into two types. The pasture chain starts from a green plant and goes on to grazing herbivores and then to predators. Examples of grazing chains are shown in the illustrations in paragraph 4.2. The detritus chain goes from dead organic matter (detritus) to decomposer microorganisms and animals that eat dead remains (detritivores), and then to predators that feed on these animals and microbes. This figure shows an example of a detritus food chain from the tropics; this is a chain starting from the falling leaves of mangroves - trees and shrubs growing on sea coasts periodically flooded by tides and in estuaries. Their leaves fall into brackish waters overgrown with mangrove trees and are carried by the current across a vast area of bays. Mushrooms, bacteria and protozoa develop in the water on fallen leaves, which, together with the leaves, are eaten by numerous organisms: fish, mollusks, crabs, crustaceans, insect larvae and roundworms - nematodes. These animals are fed by small fish (for example, minnows), and they, in turn, are eaten by large fish and predatory fish-eating birds.

FOOD CHAIN(trophic chain, food chain), the relationship of organisms through the relationship of food - consumer (some serve as food for others). In this case, the transformation of matter and energy from producers(primary producers) through consumers(consumers) to decomposers(converters of dead organics into inorganic substances digestible by producers).

There are 2 types of food chains - pasture and detrital. The pasture chain begins with green plants, goes to grazing herbivorous animals (consumers of the 1st order) and then to predators that prey on these animals (depending on the place in the chain - consumers of the 2nd and subsequent orders). The detrital chain starts with detritus (a product of the decomposition of organic matter), goes to microorganisms that feed on it, and then to detritus feeders (animals and microorganisms involved in the process of decomposition of dying organic matter).

An example of a pasture chain is its multi-channel model in the African savannah. Primary producers are herbage and trees, consumers of the 1st order are herbivorous insects and herbivores (ungulates, elephants, rhinos, etc.), 2nd order - predatory insects, 3rd order - carnivorous reptiles (snakes, etc.), 4th - predatory mammals and birds of prey. In turn, detritivores (scarab beetles, hyenas, jackals, vultures, etc.) at each stage of the pasture chain destroy the carcasses of dead animals and the remains of predators' food. The number of individuals included in the food chain consistently decreases in each of its links (the rule of the ecological pyramid), i.e., the number of victims each time significantly exceeds the number of their consumers. Food chains are not isolated from each other, but are intertwined with each other, forming food webs.

The maintenance of the vital activity of organisms and the circulation of matter in ecosystems, that is, the existence of ecosystems, depends on the constant influx of energy necessary for all organisms for their vital activity and self-reproduction (Fig. 12.19).

Rice. 12.19. Energy flow in an ecosystem (according to F. Ramad, 1981)

Unlike substances that continuously circulate through different blocks of the ecosystem, which can always be reused, enter the cycle, energy can only be used once, i.e., there is a linear flow of energy through the ecosystem.

One-way influx of energy as a universal phenomenon of nature occurs as a result of the laws of thermodynamics. First law states that energy can change from one form (such as light) to another (such as the potential energy of food), but cannot be created or destroyed. Second law argues that there can be no process associated with the transformation of energy, without the loss of some of its part. A certain amount of energy in such transformations is dissipated into inaccessible thermal energy, and therefore is lost. Hence, there can be no transformations, for example, of food substances into the substance that makes up the body of an organism, going with 100 percent efficiency.

Thus, living organisms are energy converters. And every time energy is converted, some of it is lost as heat. Ultimately, all the energy entering the biotic cycle of the ecosystem is dissipated in the form of heat. Living organisms do not actually use heat as a source of energy to do work - they use light and chemical energy.

Food chains and webs, trophic levels

Within an ecosystem, energy-containing substances are created by autotrophic organisms and serve as food for heterotrophs. Food bonds are mechanisms for transferring energy from one organism to another.

A typical example: an animal eats plants. This animal, in turn, can be eaten by another animal. In this way, energy can be transferred through a number of organisms - each subsequent one feeds on the previous one, supplying it with raw materials and energy (Fig. 12.20).

Rice. 12.20. Biotic cycling: the food chain

(according to A. G. Bannikov et al., 1985)

This sequence of energy transfer is called food (trophic) chain, or power circuit. The place of each link in the food chain is trophic level. The first trophic level, as noted earlier, is occupied by autotrophs, or the so-called primary producers. Organisms in the second trophic level are called primary consumers, third - secondary consumers etc.

Generally, there are three types of food chains. The food chain of predators begins with plants and moves from small organisms to organisms of ever larger sizes. On land, food chains consist of three to four links.

One of the simplest food chains looks like (see Fig. 12.5):

plant ® hare ® wolf

producer ® herbivore ® carnivore

The following food chains are also widespread:

plant material (e.g. nectar) ® fly ® spider ®

shrew ® owl.

rose bush juice ® aphid ® ladybug ®

® spider ® insectivorous bird ® bird of prey.

- (brought in by the current - lake, sea; brought in by man - agricultural land, carried by wind or precipitation - plant remains on eroded mountain slopes).

The differences between an ecosystem and a biogeocenosis can be reduced to the following points:

1) biogeocenosis - a territorial concept, refers to specific areas of land and has certain boundaries that coincide with the boundaries of phytocenosis. A characteristic feature of biogeocenosis, which N.V. Timofeev-Resovsky, A.N. Tyurukanov (1966) - not a single significant biocenotic, soil-geochemical, geomorphological and microclimatic boundary passes through the territory of biogeocenosis.

The concept of an ecosystem is broader than the concept of biogeocenosis; it is applicable to biological systems of varying complexity and size; ecosystems often do not have a certain volume and strict boundaries;

2) in biogeocenosis, organic matter is always produced by plants, therefore the main component of biogeocenosis is phytocenosis;

In ecosystems, organic matter is not always created by living organisms, it often comes from outside.

(brought in by the current - lake, sea; brought in by man - agricultural land, carried by wind or precipitation - plant remains on eroded mountain slopes).

3) biogeocenosis is potentially immortal;

The existence of an ecosystem can end with the cessation of the arrival of matter or energy into it.

4) an ecosystem can be both terrestrial and aquatic;

Biogeocenosis is always a terrestrial or shallow-water ecosystem.

5) - in the biogeocenosis there should always be a single edificator (edificatory grouping or synusia), which determines the whole life and structure of the system.

There may be several in an ecosystem.

In the early stages of development, the slope ecosystem is the future forest cenosis. It consists of groupings of organisms with different edificators and rather heterogeneous environmental conditions. Only in the future, the same grouping can be influenced not only by its edifier, but also by the edifier of the cenosis. And the second will be the main one.

Thus, not every ecosystem is a biogeocenosis, but each biogeocenosis is an ecosystem, which fully corresponds to Tensley's definition.

Ecological structure of biogeocenosis

Each biogeocenosis is composed of certain ecological groups of organisms, the ratio of which reflects the ecological structure of the community, which has been developing for a long time in certain climatic, soil-ground and landscape conditions in a strictly regular manner. For example, in biogeocenoses of different natural zones, the ratio of phytophages (animals that feed on plants) and saprophages naturally changes. In steppe, semi-desert and desert regions, phytophages prevail over saprophages, while in forest communities, on the contrary, saprophagy is more developed. In the depths of the ocean, the main type of food is predation, while on the illuminated surface of the reservoir, filter feeders that consume phytoplankton or species with a mixed diet predominate.

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