The relationship between the components of the biocenosis. Connections in the biocenosis

Question 1. What biocenoses in your area can serve as an example of the interrelations of components?

Question 2. Give examples of the relationships between the components of the biocenosis in an aquarium.

An aquarium can be considered as a model of a biocenosis. Of course, without human intervention, the existence of such an artificial biocenosis is practically impossible, but if certain conditions are met, its maximum stability can be achieved.

Producers in the aquarium are all types of plants - from microscopic algae to flowering plants. Plants in the process of their life produce primary substances under the influence of light. organic matter and release oxygen necessary for the breathing of all inhabitants of the aquarium.

Organic plant products are practically not used in aquariums, since aquariums, as a rule, do not contain animals that are consumers of the first order. The person takes care of feeding second order consumers - fish - with appropriate dry or live food. Very rarely found in aquariums predatory fish, which could play the role of third-order consumers.

Various representatives of mollusks and some microorganisms that process waste products of the inhabitants of the aquarium can be considered as decomposers living in the aquarium. In addition, cleaning work organic waste in the biocenosis of the aquarium is performed by a person.

Question 3. Prove that in an aquarium you can show all types of adaptability of its components to each other.

In an aquarium it is possible to show all types of adaptation of its components to each other only in conditions of very large volumes and with minimal human intervention. To do this, you must initially take care of all the main components of the biocenosis. Provide plants with mineral nutrition; organize aeration of the water, populate the aquarium with herbivorous animals, the number of which could provide food for those consumers of the first order who will feed on them; select predators and, finally, animals that perform the functions of decomposers.

Community is a historically established set of interconnected populations of plants (phytocenosis), animals (zoocenosis), fungi and microorganisms (microbocenosis) living in a certain territory.

Organization of community (biocenosis):

Always composed of ready-made parts (populations different types organisms).

Parts are interchangeable (one type can take the place of another type with similar environmental requirements).

Based on the quantitative regulation of the numbers of some species by others.

The sizes are determined by the conditions of the abiotic environment (biotope).

Biotope is a relatively homogeneous area of ​​the abiotic environment occupied by one community (biocenosis).

The basis for the existence of a community (biocenosis) is the mutual connections between its organisms:

Trophic (food) organisms feed on other organisms, or they dead remains, or products of their vital activity (dragonflies catch insects; gravedigging beetles eat the corpses of small animals and birds; dung beetles feed on droppings, etc.);

Topical: some organisms create a habitat for other organisms (lichens settle on the bark of trees, sea acorns settle on the skin of whales, etc.);

Phoric: some organisms participate in the spread of other organisms (animals carry fruits with attachments on their fur, blackbirds and jays spread tree seeds, etc.);

Factory: some organisms use excretory products or dead remains of other organisms to build their nests and homes (birds use tree branches, animal fur, grass, leaves to build nests; caddis fly larvae build houses from pieces of branches and mollusk shells, etc.)

Community (biocenosis) structure.

Species structure– species diversity and the ratio of species in terms of numbers and population density. There are communities rich in species (coral reef, tropical rain forest, etc.) and poor (arctic tundra, deserts, swamps, etc.).

Species that predominate in numbers are dominant species. Among the dominant species, there are species that create a habitat for the entire community - edificator species (in a spruce forest - spruce, in a birch forest - birch, etc.).

Rare and small species increase the diversity of connections in the community and serve as a reserve for replacing dominant species. The more specific the environmental conditions, the poorer species composition and higher numbers of individual species. Conversely, in rich communities all species are scarce. The higher the species diversity, the more stable the community.

Spatial structure– distribution of organisms (mainly plants) across aboveground and underground layers. The tiers form the above-ground vegetative organs of plants and their root systems. The tiers are well defined in the forest (woody, shrubby, herbaceous, mossy). In addition to the vertical, there is a horizontal distribution of organisms in the community - mosaic. The mosaic pattern is due to the heterogeneity of the microrelief, the activities of plants, animals and humans (soil emissions, trampling of grass, cutting down trees, etc.).

Trophic structure– food chains consisting of individual organisms that are in trophic relationships with each other. Food chains form complex weaves in a community - food (trophic) networks.

Ecological structure– the ratio of ecological groups of organisms that make up the community. The diversity and abundance of representatives of a particular ecological group depend on environmental conditions (in deserts, xerophytic plants and xerophilic animals predominate; in aquatic communities, hydrophytic plants and hydrophilic animals, etc.) communities with a similar ecological structure may have different species composition, so how the same ecological niches are occupied by different species (the same ecological niche is occupied by the marten in the European taiga, and by the sable in the Siberian taiga).

two populations of animals cannot be classified as the same species if the individuals of these populations a) do not interbreed with each other b) are different

from each other in size c) have a common habitat d) inhabit different tiers

Choose one correct statement from the four given
.1. Correctly composed power supply circuit:
a) rotten stump - honey fungus - mouse - snake - hawk;
b) mouse - rotten stump - honey fungus - snake - hawk;
c) hawk - snake - mouse - rotten stump - honey fungus;
d) honey fungus - rotten stump - mouse - snake - hawk.
2. Graphic representation of the relationship between producers, consumers and decomposers in a biocenosis, expressed in units of mass, number of individuals or energy:
a) power circuit;
b) power supply network;
c) ecological pyramid;
d) ecological column.
3. Effective use The energy of sunlight by forest plants is achieved thanks to:
A) a large number stomata in the skin of leaves;
b) the presence of hairs on the surface of the leaves
c) multi-tiered arrangement of plants;
d) flowering of plants before leaves form.
4. All food relationships between organisms in biocenoses
a) power circuit;
b) power supply network;
c) ecological pyramid;
d) ecological column.
5. Environmental factors should be considered:
a) factors causing changes in the genotype of living organisms;
b) factors causing adaptation of organisms to a changing environment;
c) any factors acting on the body;
d) elements of the environment that allow the organism to survive in the struggle for existence.
6. Air temperature, air humidity, sunlight are: a) abiotic factors;
b) abiotic factors of relief; c) biotic factors;
d) anthropogenic factors.
7. Pine forest, spruce forest, meadow, swamp - examples of: a) biocenoses; b) biogeocenoses; c) agrocenoses; d) biomes.
8. Second-order consumers include: a) hamster, b) lizard; c) grasshopper; d) vole.
9. The transfer of matter and energy from one type of organism to another is called: a) a pyramid of numbers; b) food chain; c) energy pyramid; d) ecological pyramid.
10. Consumers of the first order include: a) wolf, b) jackal; c) lynx; d) vole.
II. Choose three correct statements from the six given.
1. Factors regulating the number of species in biocenoses: a) change in the amount of food; b) change in the number of predators; c) commercial hunting; d) infectious diseases; e) fishing with a rod; e) construction of a country house
.2. Biocenoses include: a) meadow; b) apple orchard; c) lake; G) pine forest; e) wheat field; e) park.
3. Agrocenoses include: a) meadow; b) apple orchard; c) lake; d) pine forest; e) wheat field; e) park.
III. Find the matches. Write the numbers of statements corresponding to the given concepts.
1. Components of a biocenosis.A) Decomposers: ____________________________B) Producers ___________________________C) First order consumers:____________D) Second order consumers:_________________1) herbivorous organisms; 2) carnivorous organisms; 3) green plants; 4) organisms that destroy organic compounds
.2. Environmental factors:A) Biotic:___________________________B) Abiotic:___________________________1) light; 2) temperature; 3) terrain; 4) plants; 5) animals; 6) person.IV. Read the text. Using the words below for reference (word list is redundant), fill in the missing terms (endings may change).1. Environmental conditions affecting living organisms of biocenoses are called __________ factors. They come in three types: _________ -- influence inanimate nature, ________ - interactions with other organisms, ___________ - generated by human activity. The latter can be direct and ___________ factors. a) environmental; b) optimal; c) biotic; d) biotic; e) limiting; f) anthropogenic; h) periodic; g) indirect; i) indefinite. Word numbers: ________________________.2. The functional groups of organisms in the biocenosis are: _________, or producers; ____________, or consumers; ___________, or destroyers. a) producers; b) parasites; c) decomposers; d) consumers; d) saprophytes. Word numbers:_______________________________________.

In this way, the transfer of energy and matter occurs, which underlies the cycle of substances in nature. There can be a lot of such chains in a biocenosis; they can include up to six links.

An example would be oak, it is a producer. Caterpillars of the oak leaf roller butterfly, eating green leaves, receive the energy accumulated in them. The caterpillar is the primary consumer, or consumer of the first order. Part of the energy found in the leaves is lost when they are processed by the caterpillar, part of the energy is spent by the caterpillar on vital activity, part of the energy goes to the bird that pecked the caterpillar - this is a secondary consumer, or secondary consumer. If a bird becomes a victim of a predator, its carcass will become a source of energy for a tertiary consumer. Bird of prey in the future it may die, and its corpse may be eaten by a wolf, crow, magpie or carrion-eating insects. Their work will be completed by microorganisms - decomposers.

They are very rare in nature, but there are organisms that eat only one type of plant or animal. They are called monophages, for example, the Apollo caterpillar butterfly feeds only on sedum leaves (Fig. 2), and giant panda- only with bamboo leaves of several types (Fig. 2).

Rice. 2. Monophages ()

Oligophages- these are organisms that feed on representatives of a few species, for example, a caterpillar wine hawkmoth eats fireweed, bedstraw, impatiens and several other plant species (Fig. 3). Polyphages capable of eating a variety of foods, the tit is a characteristic polyphagous (Fig. 3).

Rice. 3. Representatives of oligophages and polyphages ()

When feeding, each subsequent link food chain loses part of the substances obtained from food and loses part of the energy received; about 10% of the energy is spent on increasing one’s own mass total mass of food eaten, the same happens with energy, a food pyramid is obtained (Fig. 4).

Rice. 4. Food pyramid ()

About 10% goes to each tier of the food pyramid potential energy feed, the rest of the energy is lost during the digestion of food and is dissipated in the form of heat. The food pyramid allows you to assess the potential productivity of natural biocenoses. IN artificial biocenoses it allows you to assess the efficiency of management or the need for some changes.

Food, or trophic, connections of animals can manifest themselves directly or indirectly, direct connections- This is the animal directly eating its food.

Indirect trophic connections- this is either competition for food, or, conversely, involuntary assistance of one species to another in capturing food.

Each biocenosis is characterized by its own special set of components, various species of animals, plants, fungi and bacteria. Close connections are established between all these living beings; they are extremely diverse and can be divided into three large groups: symbiosis, predation and amensalism.

Symbiosis- this is a close and long-term coexistence of representatives of different biological species. With long-term symbiosis, these species adapt to each other, their mutual adaptation.

Mutually beneficial symbiosis is called mutualism.

Commensalism- these are relationships that are useful to one, but indifferent to the other symbiont.

Amensalism- a type of interspecific relationship in which one species, called the amensal, undergoes inhibition of growth and development, and the second, called the inhibitor, is not subject to such tests. Amensalism is fundamentally different from symbiosis in that neither species benefits; such species, as a rule, do not live together.

These are forms of interaction between organisms of different species (Fig. 4).

Rice. 5. Forms of interaction between organisms of different species ()

The long-term coexistence of animals in the same biocenosis leads to the division of food resources between them, which reduces competition for food. Only those animals survived that found their food and specialized, adapting to eat it. Can be highlighted environmental groups based on the predominant food items, for example, herbivorous animals are called phytophages(Fig. 6). Among them we can highlight phyllophagous(Fig. 6) - animals that eat leaves, carpophagous- eating fruits, or xylophages- wood eaters (Fig. 7).

Rice. 6. Phytophages and phyllophages ()

Rice. 7. Carpophagous and xylophagous ()

Today we discussed the relationship between the components of a biocenosis, got acquainted with the variety of relationships between the components in a biocenosis and their adaptability to life in one community.

References

1. Latyushin V.V., Shapkin V.A. Biology Animals. 7th grade, - Bustard, 2011
2. Sonin N.I., Zakharov V.B. Biology. Diversity of living organisms. Animals. 8th grade, - M.: Bustard, 2009
3. Konstantinov V.M., Babenko V.G., Kuchmenko V.S. Biology: Animals: Textbook for 7th grade students of general education institutions / Ed. prof. V.M. Konstantinov. - 2nd ed., revised. - M.: Ventana-Graf.

Homework

1. What relationships exist between organisms in a biocenosis?
2. How do relationships between organisms affect the stability of a biocenosis?
3. In connection with what are ecological groups formed in a biocenosis?

1. Internet portal Bono-esse.ru ( ).
2. Internet portal Grandars.ru ().
3. Internet portal Vsesochineniya.ru ().

BASICS OF GENERAL ECOLOGY

1.1. STRUCTURE OF MODERN ECOLOGY

All environmental sciences can be systematized either by objects of study or by the methods they use.

1. In accordance with the size of the objects of study, the following directions are distinguished:

Autoecology (Greek autos - himself) is a section of ecology that studies the relationship of an individual organism (an artificially isolated organism) with the environment;

Demecology (Greek demos - people) - studies the population and its environment;

Eidecology (Greek eidos - image) - ecology of species;

Synecology (Greek syn - together) - considers communities as integral systems;

Landscape ecology - studies the ability of organisms to exist in different geographic environments;

Megaecology or global ecology is the science of the Earth's biosphere and the position of man in it.

2. In accordance with the relationship to the object of study, the following sections of ecology will be distinguished:

Ecology of microorganisms;

Ecology of mushrooms;

Plant ecology;

Animal ecologists;

Social ecology - examines the interaction of man and human society with the environment;

Human ecology - includes the study of the interaction of human society with nature, the ecology of the human personality and the ecology of human populations, including the doctrine of ethnic groups;

Industrial or engineering ecology - examines the mutual influence of industry and transport on nature;

Agricultural ecology - studies ways to obtain agricultural products without depletion natural resources;

Medical ecology - studies human diseases associated with environmental pollution and methods of their prevention and treatment.

3. In accordance with the environments and components, the following disciplines are distinguished:

Ecology of land;

Ecology of the seas;

Ecology of rivers;

Ecology of deserts;

Forest ecology - studies ways to use forest resources while constantly restoring them;

Ecology of the highlands;

Urban ecology (lat. urbanus - urban) - ecology of urban planning;

4. In accordance with the methods used, the following applied environmental sciences are distinguished:

Mathematical ecology - creates mathematical models for the purpose of predicting the state and behavior of populations and communities when environmental conditions change;

Chemical ecology - develops methods for analyzing pollutants and ways to reduce harm from chemical pollution;

Economic ecology - creates economic mechanisms for rational environmental management;

Legal ecology - aims to develop a system of environmental laws.

1.2.LEVELS OF ORGANIZATION OF LIVING MATTER

In order to get a holistic understanding of ecology and understand the role it plays among the sciences that study living organisms, it is necessary to become familiar with the concept of the levels of organization of living matter and the hierarchy of biological systems (Fig. 1).

Biosystems are systems in which biotic components (all living organisms) different levels organizations interact with their environment in an orderly manner biotic environment, i.e. abiotic components (energy and matter).

Fig.1. Hierarchy of levels of organization of living matter:

Molecular - processes such as metabolism and energy conversion, transmission hereditary information;

Cellular - the cell is the basic structural and functional unit of all life on planet Earth;

Organismic - organism (lat. organizo - arrange, give a harmonious appearance) is used in the narrow sense - individual, individual, “ living creature”, and in the broadest, most in a general sense- a complexly organized whole. This is a real carrier of life, characterized by all its signs;

Population-species - population (lat. populus - people), according to the definition of academician S. S. Schwartz, is an elementary grouping of organisms of a certain species, possessing all necessary conditions to maintain its numbers is boundless long time in constantly changing conditions. The term “population” was introduced by V. Yogasen in 1903. A population is a specific form of existence of a species in nature. A biological species is a collection of individuals that have common features, capable of freely interbreeding with each other and producing fertile offspring, occupying a certain area (Latin area - area, space) and delimited from other species by non-crossing in natural conditions. The idea of ​​species as the main structural and classification unit in the system of living organisms was introduced by C. Linnaeus, who published his work “Systems of Nature” in 1735;

Biocenotic - biocenosis (Greek bios - life, koinos - general) - a collection of organisms of different species and of varying complexity organization with all the factors of a specific environment. The term “biocenosis” was proposed by K. Möbius in 1877. The habitat of a biocenosis is called a biotope. A biotope (Greek bios - life, topos - place) is a space with homogeneous conditions (relief, climate) inhabited by a certain biocenosis. Any biocenosis is inextricably linked with a biotope, forming together with it a stable biological macrosystem of an even higher rank - a biogeocenosis. The term “biogeocenosis” was proposed in 1940 by Vladimir Nikolaevich Sukachev. According to V.N. Sukachev, biogeocenosis is a collection over a certain extent earth's surface homogeneous natural phenomena: atmosphere, rock, hydrological conditions, vegetation, fauna, microorganisms and soil. Thus, the concept of biocenosis is used to refer only to terrestrial ecosystems, the boundaries of which are determined by the boundaries of the phytocenosis (vegetation). Biogeocenosis is special case large ecosystem;

Biosphere (Greek bios - life, spharia - ball) - a global ecosystem of everything globe, the shell of the Earth, consisting of the totality of all living organisms (biota), substances, their components and their habitat. The biosphere is the area of ​​distribution of life on Earth, including the lower part of the atmosphere, the entire hydrosphere and top part lithosphere. The term “biosphere” was introduced by the Austrian geologist E. Suess in 1873. The main provisions of the doctrine of the biosphere were published by V. I. Vernadsky in 1926. In his work, which is called “Biosphere,” V. I. Vernadsky develops the idea of ​​the evolution of the surface the globe as a holistic process of interaction between inanimate or “inert” matter and living matter.

1.4. BASIC CRITERIA FOR THE TYPE

Total number biological species on Earth, according to various estimates, range from 1.5 to 3 million. To date, about 0.5 million plant species and approximately 1.5 million animal species have been described. Man is one of the known biological species on Earth today.

The evolutionary stability of a species is ensured by the existence of genetically diverse populations within the species. The species differ from each other in many ways.

Species criteria are characteristics and properties characteristic of a species. There are morphological, genetic, physiological, geographical and environmental criteria for the species. To establish whether individuals belong to the same species, it is not enough to use any one criterion. Only the application of a set of criteria with mutual confirmation of various characteristics and properties of individuals in their totality characterizes a species.

The morphological criterion is based on the similarity of external and internal structure individuals of the same species. But individuals within a species are sometimes so variable that only by morphological criterion It is not always possible to determine the species. In addition, there are species that are morphologically similar, but individuals of such species do not interbreed - these are twin species.

Genetic criteria are a set of chromosomes characteristic of each species, their strictly defined number, size and shape. It is the main characteristic of the species. Individuals of different species having different sets of chromosomes cannot interbreed. However, in nature there are cases when individuals of different species interbreed and produce fertile offspring.

The physiological criterion is the similarity of all life processes in individuals of the same species, first of all, the similarity of the reproductive processes.

The geographical criterion is a certain area (territory, water area) occupied by a species in nature.

Ecological criterion is a combination of factors external environment, in which the species exists.

1.5. POPULATION AND TYPES OF INTERACTIONS CHARACTERISTIC FOR IT

In the life of any living creature, relationships with representatives of their own species play an important role. These relationships are carried out in populations.

The following types of populations are distinguished:

An elementary (local) population is a group of individuals of the same species occupying a small area of ​​homogeneous living conditions.

Ecological population is a set of elementary populations. These are mainly intraspecific groups confined to specific ecosystems.

Geographic populations - totality ecological populations, inhabiting a territory with geographically homogeneous living conditions.

Relationships in populations are intraspecific interactions. The nature of these interactions makes populations of different species extremely diverse. In populations there are all types of connections inherent in living organisms, but the most common are mutually beneficial and competitive relations. In some species, individuals live alone, meeting only to reproduce. Others create temporary or permanent families. Some, within populations, unite into large groups: flocks, herds, colonies. Others form clusters during unfavorable periods, surviving winter or drought together. A population has characteristics that characterize the group as a whole, rather than the individual individuals in the group. Such characteristics are the structure, size and density of the population. Population structure is the quantitative ratio of individuals of different sexes, ages, sizes, genotypes, etc. Accordingly, sex, age, size, genetic and other population structures are distinguished.

Population structure depends on various reasons. For example, the age structure of a population depends on two reasons:

From features life cycle type;

From external conditions.

There are species with a very simple age population structure, which consist practically of representatives of the same age (annual plants, locusts). Complex age structures of populations arise when all age groups(a flock of monkeys, a herd of elephants).

Unfavorable external conditions can change the age composition of the population due to the death of the weakest individuals, but the most stable age groups survive and then restore the population structure. The spatial structure of a population is determined by the nature of the distribution of individuals in space and depends both on the characteristics environment, and on the behavioral characteristics of the species itself. Any population has a tendency to disperse. Dispersal continues until the population encounters any obstacle. The main parameters of a population are its size and density.

Population size is total quantity individuals in a given territory or in a given volume. The level of population size that guarantees its conservation depends on the specific biological species.

Population density is the number of individuals per unit area or volume. The higher the number, the higher the adaptability of organisms in a given population. The population size is never constant and depends on the ratio of reproduction intensity (fertility) and mortality, i.e. the number of individuals that died during a certain period. Population density is also variable, depending on the number. As numbers increase, density does not increase only if expansion of the population range is possible. In nature, the size of any population is extremely dynamic.

The population regulates its numbers and adapts to changing environmental conditions by updating and replacing individuals. Individuals appear in a population through birth and immigration and disappear through death and emigration.

The population size is also influenced by the age composition, the total life expectancy of individuals, the period of reaching sexual maturity, and the duration of the breeding season.

For the population of each species there are upper and lower density limits, beyond which it cannot go. These resource limits are called the carrying capacity of the environment for specific populations. In natural conditions, due to the ability of self-regulation, the population size usually fluctuates around a certain level corresponding to the capacity of the environment.

BIOCENOSIS AND CHARACTERISTIC RELATIONSHIPS

Biocenoses are not random gatherings different organisms. In similar natural conditions and with a similar composition of fauna and flora, similar, naturally repeating biocenoses arise. Biocenoses have a species and spatial structure.

The species structure of a biocenosis means the number of species in a given biocenosis. The diversity of species reflects the diversity of habitat conditions. Species that dominate in numbers in a community are called dominants. Dominant species determine the main connections in the biocenosis, create its basic structure and appearance. Typically, terrestrial biocenoses are named by their dominant species (birch grove, spruce forest, feather grass steppe). Part mass species- these are species without which other species cannot exist. They are called edificators (environment formers); their removal will lead to the complete destruction of the community. Usually the dominant species is also the edificator. The most diverse species in biocenoses are rare and small in number. Few species constitute a reserve of the biocenosis. Their predominance is a guarantee sustainable development. In the richest biocenoses, basically all species are small in number, but the less diversity, the more dominants there are.

The spatial structure of the biocenosis is determined by the characteristics of the atmosphere, the rock of the soil and its waters. During a long evolutionary transformation, adapting to certain conditions, living organisms are located in biocenoses in such a way that they practically do not interfere with each other. The basis of this distribution is formed by vegetation. Plants create tiers in biocenoses, placing foliage under each other in accordance with their growth form and photophilia.

Each tier develops its own system of relationships, so the tier can be considered as a structural unit of the biocenosis.

In addition to tiers, mosaicism is observed in the spatial structure of the biocenosis - a horizontal change in the vegetation of the animal world.

Neighboring biocenoses usually gradually transform into one another; a clear boundary cannot be drawn between them. In the border zone, the typical conditions of neighboring biocenoses intertwine, some species of plants and animals disappear and others appear. Species that have adapted in the border zone are called ecotones. The abundance of plants attracts a variety of animals here, so that the border zone turns out to be more diverse and rich in species than each of the adjacent biocenoses. This phenomenon is called the edge effect and is often used when creating parks where they want to restore species diversity.

The species structure of a biocenosis, the spatial distribution of species within a biotope, is mainly determined by the relationships between species and the functional role of the species in the community.

ECOLOGICAL NICHE

To determine the role that a particular species plays in the composition of an ecosystem, J. Grinnell introduced the concept of “ecological niche.” An ecological niche is a set of all environmental parameters within which the existence of a species in nature is possible, its position in space and its functional role in the composition of the ecosystem. Yu. Odum figuratively presented an ecological niche as an occupation, a “profession” of an organism in a biocenosis, and its habitat is the “address” of the species where it lives. In order to study an organism, you need to know not only its address, but also its profession. G. E. Hutchinson quantified the ecological niche. In his opinion, the niche must be determined taking into account all the physical, chemical and biotic environmental factors to which the species must be adapted. G. E. Hutchinson distinguishes two types of ecological niche: fundamental and realized. Ecological niche defined only physiological characteristics organisms is called fundamental (potential), and that within which the species actually occurs in nature is called realized. The latter is that part of the potential niche that this type able to stand up to competition. Species coexist in one ecosystem as part of a biocenosis in cases where they diverge in environmental requirements and thereby weaken competition with each other. Two species in the same biocenosis cannot occupy the same ecological niche. Often even closely related species, living nearby in the same biocenosis, occupy different ecological niches. This leads to a decrease in competitive tension between them. Moreover, the same type different periods its development can occupy different ecological niches.

Intraspecific and interspecific relationships of organisms in a biocenosis

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