Biogeocenosis is a concept that combines three principles: “bios” (life), “geo” (earth) and “koinos” (general). Based on this, the word “biogeocoenosis” refers to a specific developing system in which living organisms and inanimate objects constantly interact. They are links in the same food chain and are united by the same energy flows. This concerns, first of all, the place of contact between living and inanimate nature. For the first time V.N. spoke about biogeocenosis. Sukachev, famous Soviet scientist and thinker. In 1940, he deciphered this concept in one of his articles, and this term began to be widely used in Russian science.

Biogeocenosis and ecosystem

The concept of “biogeocenosis” is a term that is used only by Russian scientists and their colleagues from the CIS countries. In the West, there is an analogue of the term, authored by the English botanist A. Tansley. He introduced the word “ecosystem” into scientific use in 1935, and by the early 1940s it had already become generally accepted and discussed. At the same time, the concept of “ecosystem” has a broader meaning than “biogeocenosis”. To some extent, we can say that biogeocenosis is a class of ecosystem. So what is an ecosystem? This is the connection of all types of organisms and their habitat into one single system, which is in balance and harmony, lives and develops according to its own laws and principles. At the same time, an ecosystem, unlike a biogeocenosis, is not limited to a piece of land. Therefore, biogeocenosis is part of the ecosystem, but not vice versa. An ecosystem can contain several types of biogeocenosis at once. Let’s say that the ecosystem of the belt includes the biogeocenosis of the continent and the biogeocenosis of the ocean.

Structure of biogeocenosis

The structure of biogeocenosis is a very broad concept that lacks certain indicators. This is explained by the fact that it is based on a variety of organisms, populations, and objects of the surrounding world, which can be divided into biotic (living organisms) and abiotic (environment) components.

The abiotic part also consists of several groups:

• inorganic compounds and substances (oxygen, hydrogen, nitrogen, water, hydrogen sulfide, carbon dioxide);
• organic compounds that serve as food for organisms of the biotic group;
• climate and microclimate, which determines the living conditions for all systems that are located in it.

The concept of “ecosystem” was introduced in 1935 by A. Tansley, an English botanist. With this term he designated any collection of organisms living together, as well as their environment. Its definition emphasizes the presence of interdependence, relationships, cause-and-effect relationships that exist between the abiotic environment and the biological community, combining them into a certain functional whole. An ecosystem, according to biologists, is a collection of all kinds of populations of various species that live in a common territory, as well as the inanimate environment that surrounds them.

Biogeocenosis is a natural formation that has clear boundaries. It consists of a set of biocenoses (living beings) that occupy a certain place. For example, for aquatic organisms this place is water, for those living on land it is the atmosphere and soil. Below we will look at which will help you understand what it is. We will describe these systems in detail. You will learn about their structure, what types they exist and how they change.

Biogeocenosis and ecosystem: differences

To some extent, the concepts of “ecosystem” and “biogeocenosis” are unambiguous. However, they do not always coincide in volume. Biogeocenosis and ecosystem are related as a less broad and broader concept. An ecosystem is not connected to a certain limited area of ​​the earth's surface. This concept can be applied to all stable systems of nonliving and living components in which internal and external circulation of energy and substances occurs. Ecosystems, for example, include a drop of water with microorganisms in it, a flower pot, an aquarium, a biofilter, an aeration tank, and a spaceship. But they cannot be called biogeocenoses. An ecosystem may also contain several biogeocenoses. Let's look at some examples. We can distinguish biogeocenoses of the ocean and biosphere as a whole, continent, belt, soil-climatic region, zone, province, district. Thus, not every ecosystem can be considered a biogeocenosis. We found this out by looking at examples. But any biogeocenosis can be called an ecological system. We hope you now understand the specifics of these concepts. “Biogeocenosis” and “ecosystem” are often used as synonyms, but there is still a difference between them.

Features of biogeocenosis

Many species usually live in any of the limited spaces. A complex and permanent relationship is established between them. In other words, different types of organisms that exist in a certain space, characterized by a set of special physical and chemical conditions, represent a complex system that persists for a more or less long time in nature. To clarify the definition, we note that a biogeocenosis is a community of organisms of various species (historically established), which are closely related to each other and to their surroundings, the exchange of energy and substances. A specific characteristic of a biogeocenosis is that it is spatially limited and quite homogeneous in the species composition of the living creatures included in it, as well as in the complex of various Existence as an integral system ensures a constant supply of solar energy to this complex. As a rule, the boundary of a biogeocenosis is established along the boundary of a phytocenosis (plant community), which is its most important component. These are its main features. The role of biogeocenosis is great. At its level, all processes of energy flow and circulation of substances in the biosphere occur.

Three groups of biocenosis

The main role in the interaction between its various components belongs to the biocenosis, that is, living beings. They are divided according to their functions into 3 groups - decomposers, consumers and producers - and closely interact with the biotope (inanimate nature) and with each other. These living beings are united by the food connections that exist between them.

Producers are a group of autotrophic living organisms. By consuming the energy of sunlight and minerals from the biotope, they thereby create primary organic substances. This group includes some bacteria, as well as plants.

Decomposers decompose the remains of dead organisms, and also break down organic substances into inorganic substances, thereby returning mineral substances “removed” by producers to the biotope. These are, for example, some types of unicellular fungi and bacteria.

Dynamic equilibrium of the system

Types of biogeocenosis

Biogeocenosis can be natural and artificial. The types of the latter include agrobiocenoses and urban biogeocenoses. Let's take a closer look at each of them.

Natural biogeocenosis

Let us note that every natural biogeocenosis is a system that has developed over a long period of time - thousands and millions of years. Therefore, all its elements are “ground in” to each other. This leads to the fact that the resistance of the biogeocenosis to various changes occurring in the environment is very high. The "strength" of ecosystems is not unlimited. Profound and abrupt changes in living conditions, a reduction in the number of species of organisms (for example, as a result of large-scale fishing of commercial species) lead to the fact that the balance can be disturbed and it can be destroyed. In this case, a change in biogeocenoses occurs.

Agrobiocenoses

Agrobiocenoses are special communities of organisms that develop in areas used by people for agricultural purposes (plantings, crops of cultivated plants). Producers (plants), in contrast to natural biogeocenoses, are represented here by one type of crop grown by humans, as well as a certain number of weed species. Diversity (rodents, birds, insects, etc.) determines the vegetation cover. These are species that can feed on plants growing on the territory of agrobiocenoses, as well as be in conditions of their cultivation. These conditions determine the presence of other species of animals, plants, microorganisms and fungi.

Agrobiocenosis depends, first of all, on human activities (fertilization, mechanical tillage, irrigation, treatment with pesticides, etc.). The stability of the biogeocenosis of this species is weak - it will collapse very quickly without human intervention. This is partly due to the fact that cultivated plants are much more demanding than wild ones. Therefore, they cannot compete with them.

Urban biogeocenoses

Urban biogeocenoses are of particular interest. This is another type of anthropogenic ecosystem. An example is parks. The main ones, as in the case of agrobiocenoses, are anthropogenic. The species composition of plants is determined by humans. He plants them and also cares for and processes them. Changes in the external environment are most pronounced in cities - an increase in temperature (from 2 to 7 ° C), specific features of soil and atmospheric composition, a special regime of humidity, light, and wind action. All these factors form urban biogeocenoses. These are very interesting and specific systems.

Examples of biogeocenosis are numerous. Different systems differ from each other in the species composition of organisms, as well as in the properties of the environment in which they live. Examples of biogeocenosis, which we will dwell on in detail, are a deciduous forest and a pond.

Deciduous forest as an example of biogeocenosis

Deciduous forest is a complex ecological system. The biogeocenosis in our example includes plant species such as oaks, beeches, lindens, hornbeams, birches, maples, rowan trees, aspens and other trees whose leaves fall in the fall. Several of their tiers stand out in the forest: low and high trees, moss ground cover, grasses, shrubs. Plants inhabiting the upper tiers are more light-loving. They withstand fluctuations in humidity and temperature better than representatives of the lower tiers. Mosses, grasses and shrubs are shade-tolerant. They exist in the summer in the twilight formed after the leaves of the trees unfold. The litter lies on the surface of the soil. It is formed from semi-decomposed remains, twigs of bushes and trees, fallen leaves, and dead grass.

Forest biogeocenoses, including deciduous forests, are characterized by a rich fauna. They are inhabited by many burrowing rodents, predators (bear, badger, fox), and burrowing insectivores. There are also tree-dwelling mammals (chipmunk, squirrel, lynx). Roe deer, moose, and deer are part of the group of large herbivores. Boars are widespread. Birds nest in different layers of the forest: on trunks, in bushes, on the ground or on the tops of trees and in hollows. There are many insects that feed on leaves (for example, caterpillars), as well as wood (bark beetles). In addition to insects, the upper layers of the soil, as well as the litter, contain a huge number of other vertebrates (ticks, earthworms, insect larvae), many bacteria and fungi.

Pond as a biogeocenosis

Let's now consider a pond. This is an example of a biogeocenosis, in which the living environment of organisms is water. Large floating or rooting plants (pondweed, water lilies, reeds) settle in the shallow waters of ponds. Small floating plants are distributed throughout the water column, to the depth where light penetrates. These are mainly algae called phytoplankton. Sometimes there are a lot of them, as a result of which the water turns green and “blooms.” A variety of blue-green, green and diatom algae are found in phytoplankton. Tadpoles, insect larvae, and crustaceans feed on plant debris or living plants. Fish and predatory insects eat small animals. And herbivorous and smaller predatory fish are hunted by large predatory fish. Organisms that decompose organic matter (fungi, flagella, bacteria) are widespread throughout the pond. There are especially many of them at the bottom, since the remains of dead animals and plants accumulate here.

Comparison of two examples

Having compared examples of biogeocenosis, we see how different the ecosystems of a pond and a forest are in both species composition and appearance. This is due to the fact that the organisms inhabiting them have different habitats. In a pond it is water and air, in a forest it is soil and air. Nevertheless, the functional groups of organisms are of the same type. In the forest, producers are mosses, grasses, shrubs, and trees; There are algae and floating plants in the pond. In the forest, consumers include insects, birds, animals and other invertebrates that inhabit the litter and soil. Consumers in the pond include various amphibians, insects, crustaceans, predatory and herbivorous fish. In the forest, decomposers (bacteria and fungi) are represented by terrestrial forms, and in a pond - by aquatic ones. Let us also note that both the pond and the deciduous forest are a natural biogeocenosis. We gave examples of artificial ones above.

Why do biogeocenoses replace each other?

Biogeocenosis cannot exist forever. It will inevitably sooner or later be replaced by another. This occurs as a result of changes in the environment by living organisms, under the influence of humans, in the process of evolution, and with changing climatic conditions.

An example of a change in biogeocenosis

Let us consider, as an example, the case when living organisms themselves cause a change in ecosystems. This is the colonization of rocks with vegetation. Weathering of rocks is of great importance in the first stages of this process: partial dissolution of minerals and changes in their chemical properties, destruction. At the initial stages, the first settlers play a very important role: algae, bacteria, blue-greens. The producers are free-living algae and lichens. They create organic matter. Blue-greens take nitrogen from the air and enrich it with it in an environment that is still unsuitable for habitation. Lichens dissolve rock with secretions of organic acids. They contribute to the gradual accumulation of mineral nutrition elements. Fungi and bacteria destroy organic substances created by producers. The latter are not completely mineralized. A mixture consisting of mineral and organic compounds and nitrogen-enriched plant residues gradually accumulates. Conditions are created for the existence of bushy lichens and mosses. The process of accumulation of nitrogen and organic matter accelerates, and a thin layer of soil is formed.

A primitive community is formed that can exist in this unfavorable environment. The first settlers were well adapted to the harsh conditions of the rocks - they withstood frost, heat, and dryness. Gradually they change their habitat, creating conditions for the formation of new populations. After herbaceous plants (clover, grasses, sedges, bellflowers, etc.) appear, competition for nutrients, light, and water becomes more intense. In this struggle, the pioneer settlers are replaced by new species. Shrubs settle behind herbs. They hold the emerging soil together with their roots. Forest communities are replaced by grass and shrub communities.

During the long process of development and change of biogeocenosis, the number of species of living organisms included in it gradually increases. The community becomes more complex, it becomes more and more branched. The variety of connections that exist between organisms increases. The community uses the resources of the environment more and more fully. This is how it turns into a mature one, which is well adapted to environmental conditions and has self-regulation. In it, species populations reproduce well and are not replaced by other species. The described change of biogeocenoses lasts for thousands of years. However, there are changes that occur before the eyes of just one generation of people. For example, this is the overgrowing of small bodies of water.

So, we talked about what biogeocenosis is. The examples with descriptions presented above give a clear idea of ​​it. Everything we have talked about is important for understanding this topic. Types of biogeocenoses, their structure, features, examples - all this should be studied in order to have a complete understanding of them.

All communities of plants, animals, microorganisms, fungi, which are in close connection with each other, creating an inextricable system of interacting organisms and their populations - biocenosis, which is also called community.

Producers in the forest are trees, shrubs, grasses, and mosses.

Consumers are animals, birds, insects.

Decomposers are terrestrial.

Producers in the pond are floating plants, algae, and blue-green ones.

Consumers are insects, amphibians, crustaceans, herbivores and predatory fish.

Decomposers are aquatic forms of fungi and plants.

An example of an ecosystem is a deciduous forest. Deciduous forests include beeches, oaks, hornbeams, lindens, maples, aspens and other trees whose leaves fall in the fall. There are several tiers of plants in the forest: high and low woody, shrubs, grasses and moss ground cover. Plants in the upper tiers are more light-loving and better adapted to fluctuations in temperature and humidity than plants in the lower tiers. Shrubs, grasses and mosses in the forest are shade-tolerant; in summer they exist in twilight, which forms after the leaves of the trees have fully expanded. On the surface of the soil lies a litter consisting of semi-decomposed remains, fallen leaves, twigs of trees and shrubs, and dead grass.

The fauna of deciduous forests is rich. There are many burrowing rodents, burrowing insectivores, and predators. There are mammals that live in trees. Birds nest in different layers of the forest: on the ground, in bushes, on trunks or in hollows and on the tops of trees. There are many insects that feed on leaves and wood. A huge number of invertebrate animals, fungi and bacteria live in the litter and upper soil horizons.

Properties of biogeocenoses.

Sustainability.

Resilience is the ability of a community and ecosystem to withstand changes created by external influences. The ability of organisms to tolerate unfavorable conditions and high reproduction potential ensure the preservation of populations in the ecosystem, which guarantees its sustainability.

Self-regulation.

Biogeocenosis (using the example of an oak forest)
1. Dubrava as a natural community (biogeocenosis), characterized by integrity and sustainability

• The type of natural community we examined during the excursion, the oak forest, is one of the most complex among terrestrial biogeocenoses. Well, first of all, what is biogeocenosis? Biogeocenosis is a complex of interconnected species (populations of different species) living in a certain territory with more or less homogeneous living conditions. This definition will be needed for future use. Oak grove is a perfect and sustainable ecological system, capable of existing for centuries under constant external conditions. The oak forest biogeocenosis consists of more than a hundred plant species and several thousand animal species. It is clear that with such a diversity of species inhabiting the oak forest, it will be difficult to shake the stability of this biogeocenosis by exterminating one or several species of plants or animals. It is difficult, because as a result of the long coexistence of plant and animal species, from disparate species they became a single and perfect biogeocenosis - an oak forest, which, as mentioned above, is capable of existing for centuries under constant external conditions.

2. The main components of biogeocenosis and the connections between them; Plants are the main link in the ecosystem.

• The basis of the vast majority of biogeocenosis are green plants, which, as is known, are producers of organic matter (producers). And since in biogeocenosis there are necessarily herbivorous and carnivorous animals - consumers of living organic matter (consumers) and, finally, destroyers of organic residues - mainly microorganisms that bring the breakdown of organic substances to simple mineral compounds (decomposers), it is not difficult to guess why plants are the main link in the ecosystem. But because in a biogeocenosis everyone consumes organic substances, or compounds formed after the breakdown of organic substances, and it is clear that if plants, the main source of organic matter, disappear, then life in the biogeocenosis will practically disappear.

3. The circulation of substances in biogeocenosis. Importance in the cycle of plants using solar energy

• The circulation of substances in biogeocenosis is a necessary condition for the existence of life. It arose in the process of the formation of life and became more complex during the evolution of living nature. On the other hand, in order for the circulation of substances to be possible in a biogeocenosis, it is necessary to have in the ecosystem organisms that create organic substances from inorganic ones and convert the energy of solar radiation, as well as organisms that use these organic substances and convert them again into inorganic compounds. All organisms are divided into two groups according to their method of nutrition - autotrophs and heterotrophs. Autotrophs (mainly plants) use inorganic compounds from the environment to synthesize organic substances. Heterotrophs (animals, humans, fungi, bacteria) feed on ready-made organic substances that were synthesized by autotrophs. Therefore, heterotrophs depend on autotrophs. In any biogeocenosis, all reserves of inorganic compounds would very soon dry up if they were not renewed during the life activity of organisms. As a result of respiration, decomposition of animal corpses and plant debris, organic substances are transformed into inorganic compounds, which return again to the natural environment and can again be used by autotrophs. Thus, in a biogeocenosis, as a result of the vital activity of organisms, there is a continuous flow of atoms from inanimate nature to living nature and back, closing in a cycle. For the circulation of substances, an influx of energy from outside is necessary. The source of energy is the Sun. The movement of matter caused by the activity of organisms occurs cyclically; it can be used many times, while the flow of energy in this process is unidirectional. The radiation energy of the Sun in biogeocenosis is converted into various forms: into the energy of chemical bonds, into mechanical and, finally, into internal energy. From all that has been said, it is clear that the circulation of substances in a biogeocenosis is a necessary condition for the existence of life and plants (autotrophs); the most important link in it.

4. Diversity of species in the biogeocenosis, their adaptability to living together.

• A characteristic feature of the oak forest is the species diversity of vegetation. As mentioned above, the oak forest biogeocenosis consists of more than a hundred plant species and several thousand animal species. There is intense competition between plants for the basic living conditions: space, light, water with minerals dissolved in it. As a result of long-term natural selection, oak forest plants have developed adaptations that allow different species to exist together. This is clearly manifested in the layering characteristic of oak forests. The upper tier is formed by the most light-loving tree species: oak, ash, linden. Below are the accompanying less light-loving trees: maple, apple, pear, etc. Even lower is a layer of undergrowth formed by various shrubs: hazel, euonymus, buckthorn, viburnum, etc. Finally, a layer of herbaceous plants grows on the soil. The lower the tier, the more shade-tolerant the plants that form it. Tiering is also expressed in the location of root systems. Trees in the upper layers have the deepest root system and can use water and minerals from the deeper layers of the soil.

5. Food connections, ecological pyramid.

6. Populations of plants and animals; factors causing changes in numbers; self-regulation in biogeocenosis.

7. Changes in biogeocenosis in spring: in the life of plants and animals.

8. Possible directions of change in biogeocenosis.

• Any biogeocenosis develops and evolves. The leading role in the process of changing terrestrial biogeocenoses belongs to plants, but their activity is inseparable from the activity of other components of the system, and the biogeocenosis always lives and changes as a single whole. Change occurs in certain directions, and the duration of existence of various biogeocenoses is very different. An example of a change in an insufficiently balanced system is the overgrowing of a reservoir. Due to the lack of oxygen in the bottom layers of water, part of the organic matter remains unoxidized and is not used in the further cycle. In the coastal zone, the remains of aquatic vegetation accumulate, forming peaty deposits. The reservoir is becoming shallow. Coastal aquatic vegetation spreads to the center of the reservoir, and peat deposits form. The lake is gradually turning into a swamp. The surrounding ground vegetation is gradually moving towards the site of the former reservoir. Depending on local conditions, a sedge meadow, forest, or other type of biogeocenosis may appear here. The oak forest can also turn into a different type of biogeocenosis. For example, after cutting down trees, it can turn into a meadow, field (agrocenosis) or something else.

9. The influence of human activity on biogeocenosis; measures that need to be taken to protect it.

• Man has recently begun to very actively influence the life of the biogeocenosis. Human economic activity is a powerful factor in the transformation of nature. As a result of this activity, unique biogeocenoses are formed. These include, for example, agrocenoses, which are artificial biogeocenoses that arise as a result of human agricultural activity. Examples include artificially created meadows, fields, and pastures. Artificial biogeocenoses created by man require tireless attention and active intervention in their lives. Of course, there are many similarities and differences in artificial and natural biogeocenoses, but we will not dwell on this. Humans also influence the life of natural biogeocenoses, but, of course, not as much as they influence agrocenoses. An example is forestry created to plant young trees, as well as to limit hunting. An example can also be nature reserves and national parks created to protect certain species of plants and animals. Mass societies promoting the conservation and protection of the environment are also being created, such as the “green” society, etc.

10. Conclusion: using the example of an excursion walk through a natural biogeocenosis - an oak grove, we found out and analyzed why the oak grove is holistic and stable, what are the main components of the biogeocenosis, what is their role and what connections exist between them, we also analyzed why the circulation of substances in a biogeocenosis is a necessary condition for existence life, also found out how the entire diversity of species living in the oak grove does not conflict with each other, allowing each other to develop normally, analyzed what food connections exist in the oak grove and analyzed such a concept as an ecological pyramid, substantiated the factors causing changes in numbers and such a phenomenon as self-regulation, found out what changes occur in biogeocenosis in the spring and analyzed the possible directions of evolution of biogeocenosis, as well as how humans influence life in biogeocenoses. In general, using the example of oak groves, the life of biogeocenoses was completely analyzed

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a system capable of self-regulation and maintaining its composition at a certain constant level

• characterized by the circulation of substances
• an open system for the entry and exit of energy, the main source of which is the Sun
• Biogeocenosis = biocenosis + biotope.

Basic indicators

• Species composition- the number of species living in the biogeocenosis.
• Species diversity- the number of species living in a biogeocenosis per unit area or volume.

In most cases, species composition and species diversity do not coincide quantitatively, and species diversity directly depends on the study area.

• Biomass- the number of organisms of the biogeocenosis, expressed in units of mass. Most often, biomass is divided into:
  • biomass producers
  • biomass of consumers
  • biomass of decomposers
• Productivity
• Sustainability
• Self-regulation ability

Spatial characteristics

The transition of one biogeocenosis to another in space or time is accompanied by a change in the states and properties of all its components and, consequently, a change in the nature of biogeocenotic metabolism. The boundaries of a biogeocenosis can be traced on many of its components, but more often they coincide with the boundaries of plant communities (phytocenoses). The thickness of a biogeocenosis is not homogeneous either in the composition and state of its components, or in the conditions and results of their biogeocenotic activity. It is differentiated into above-ground, underground, underwater parts, which in turn are divided into elementary vertical structures - bio-geohorizons, very specific in composition, structure and state of living and inert components. To denote the horizontal heterogeneity, or mosaic nature of the biogeocenosis, the concept of biogeocenotic parcels was introduced. Like biogeocenosis as a whole, this concept is complex, since the parcel includes vegetation, animals, microorganisms, soil, and atmosphere as participants in metabolism and energy.

Mechanisms of stability of biogeocenoses

One of the properties of biogeocenoses is the ability to self-regulate, that is, to maintain its composition at a certain stable level. This is achieved thanks to the stable circulation of substances and energy. The stability of the cycle itself is ensured by several mechanisms:

• sufficiency of living space, that is, such a volume or area that provides one organism with all the resources it needs.
• richness of species composition. The richer it is, the more stable the food chain and, consequently, the circulation of substances.
• a variety of species interactions that also maintain the strength of trophic relationships.
• environment-forming properties of species, that is, the participation of species in the synthesis or oxidation of substances.
• direction of anthropogenic impact.

Thus, the mechanisms ensure the existence of unchanging biogeocenoses, which are called stable. A stable biogeocenosis that exists for a long time is called climax. There are few stable biogeocenoses in nature; stable ones are more common - changing biogeocenoses, but capable, thanks to self-regulation, of returning to their original, starting position.

Populations in nature do not live in isolation. They interact with populations of other species, forming together with them integral systems of even higher supraspecific organization level - biotic communities, ecosystems.

Community (biocenosis) is a collection of species of plants and animals that coexist for a long time in a certain space and represent a certain ecological unity.

These formations develop according to their own laws. One of the main tasks of ecology is to identify these laws; to find out how the sustainable existence and development of communities is maintained, what impact changes in various environmental factors have on them.

The fact that communities are not random formations is evidenced by the fact that similar communities arise in areas of similar geographical location and natural conditions.

Example:

The lakes of the middle zone are characterized by great similarity of fauna and flora. Among the fish population you can easily find such well-known species as roach, perch, pike, ruff, etc.

A careful study reveals not only the similarity of species in biocenoses, but also the similarity of connections between them. These connections are extremely diverse. The species included in the community supply each other with everything necessary for life - food, shelter, conditions for reproduction. The interaction of species ensures the efficient use of community resources and prevents uncontrolled growth in the number of certain organisms, i.e. plays the role of regulators that support the sustainable functioning of complex natural systems.

Biogeocenosis is a historically established set of living organisms (biocenosis) and abiotic environment, together with the area of ​​the earth's surface (biotope) they occupy.

The border of the biogeocenosis is established, as a rule, along the border of the plant community (phytocenosis) - the most important component of the biogeocenosis.

Plant communities usually do not have sharp boundaries and gradually transform into each other as natural conditions change.

Transition zones between communities are called ecotones.

Example:

On the border of forests and tundra in the north of our country there is a transition zone - forest-tundra. There are alternating woodlands, shrubs, sphagnum bogs, and meadows. At the border of forest and steppe there is a forest-steppe zone. The more humid areas of this zone are occupied by forest, while the drier areas are occupied by steppe.

From site to site, not only the composition of vegetation changes, but also the animal world, the features of material and energy exchange between organisms and their physical environment.

An ecosystem (from the Greek oikos - dwelling and systema - association) is any community of living organisms along with their physical habitat, united by metabolism and energy into a single complex.

Consideration of an ecosystem is important in cases where we are talking about the flows of matter and energy circulating between living and nonliving components of nature, the dynamics of elements that support the existence of life, and the evolution of communities. Neither an individual organism, nor a population, nor a community as a whole can be studied in isolation from the environment. An ecosystem is essentially what we call nature.

Example:

An example of an ecosystem is a pond, including the community of its inhabitants, the physical properties and chemical composition of the water, the features of the bottom topography, the composition and structure of the soil, the atmospheric air interacting with the surface of the water, and solar radiation.

Ecosystem and biogeocenosis are close concepts, but if the term “ecosystem” is suitable for designating systems of any rank, then “biogeocenosis” is a territorial concept, referring to such areas of land that are occupied by certain units of plant cover - phytocenoses.

Pay attention!

Not every ecosystem is a biogeocenosis, but every biogeocenosis is an ecosystem.

Ecosystem is a very broad concept and applies to both natural (for example, tundra, ocean) and artificial complexes (for example, an aquarium).