Natural and artificial biocenoses. Stability and development of biocenoses When did this concept appear?

In progress Everyday life Not every person notices his interaction with various people. Rushing to work, it is unlikely that anyone, except perhaps a professional ecologist or biologist, will pay special attention to the fact that he crossed a square or park. Well, I passed and passed, so what? But this is already a biocenosis. Each of us can remember examples of such involuntary but constant interaction with ecosystems, if only we think about it. Let's try to consider in more detail the question of what biocenoses are, what they are like and what they depend on.

What is biocenosis?

Most likely, few people remember that they studied biocenoses at school. 7th grade, when they covered this topic in biology, is far in the past, and completely different events are remembered. Let us remind you what a biocenosis is. This word is formed by merging two Latin words: “bios” - life and “cenosis” - general. This term denotes a collection of microorganisms, fungi, plants and animals living in the same territory, interconnected and interacting with each other.

Any biological community includes the following components of the biocenosis:

microorganisms (microbiocenosis);
vegetation (phytocenosis);
animals (zoocenosis).

Each of these components plays an important role and can be represented by individuals different types. However, it should be noted that phytocenosis is the leading component that determines microbiocenosis and zoocenosis.

When did this concept appear?

The concept of “biocenosis” was proposed by the German hydrobiologist Möbius at the end of the 19th century, when he studied the habitats of oysters in the North Sea. During the study, he found that these animals can only live in strictly defined conditions, characterized by depth, flow speed, salinity and temperature of the water. In addition, Möbius noted that, together with oysters, strictly defined species of marine plants and animals live in the same territory. Based on the data obtained, in 1937 the scientist introduced the concept we are considering to denote the unification of groups of living organisms living and coexisting in the same territory, due to historical development species and long-term The modern concept of “biocenosis” is interpreted somewhat differently by biology and ecology.

Classification

Today there are several signs according to which a biocenosis can be classified. Examples of classification based on size:

macrobiocenosis (sea, mountain ranges, oceans);
mesobiocenosis (swamp, forest, field);
microbiocenosis (flower, old stump, leaf).

Biocenoses can also be classified depending on their habitat. The following three types are recognized as the main ones:

nautical;
freshwater;
ground.

Each of them can be divided into subordinate, smaller and local groups. Thus, marine biocenoses can be divided into benthic, pelagic, shelf and others. Freshwater biological communities are river, swamp and lake. Terrestrial biocenoses include coastal and inland, mountain and lowland subtypes.

The simplest classification of biological communities is their division into natural and artificial biocenoses. Among the former, there are primary ones, formed without human influence, as well as secondary ones, which have undergone changes due to the influence of natural elements or the activities of human civilization. Let's take a closer look at their features.

Natural biological communities

Natural biocenoses are associations of living beings created by nature itself. Such communities are natural systems that form, develop and function according to their own special laws. The German ecologist W. Tischler identified the following features characterizing such formations:

1. Communities emerge from ready-made elements that can act as representatives individual species, and entire complexes.

2. Parts of the community may be replaceable. Thus, one species can be supplanted and completely replaced by another that has similar requirements for living conditions, without negative consequences for the entire system.

3. Due to the fact that interests in the biocenosis various types are opposite, then the entire supraorganismal system is based and exists thanks to the balancing of forces directed in the opposite direction.

In addition, in biological communities there are edificators, that is, animal or plant species that create the necessary conditions for life for other creatures. So, for example, in steppe biocenoses the most powerful edificator is feather grass.

In order to assess the role of a particular species in the structure of a biological community, quantitative indicators are used, such as its abundance, frequency of occurrence, Shannon diversity index and species saturation.

Goals and objectives of the lesson:

Formation of knowledge among students:

about biocenosis as a sustainable system;
about natural and artificial biocenoses;
about the obligatory components of the biocenosis:
Introducing students to the reasons for the stability of natural biocenosis and the instability of artificial ones.

Lesson type. Discussion lecture using presentation.

Equipment. Computers, projector, CD "Biology", electronic tests.

During the classes:

I. Updating knowledge.

Individual survey:

1. What is the evidence that natural selection is the leading cause of animal evolution?

2. Why is the emergence of habitats in nature and their types the result of the adaptation of animals?

3. What are the patterns of distribution of animals in nature?

II. Learning new material.

Children, looking at the topic of the lesson, formulate the goals and objectives of the lesson.

! (suggested answer):

find out what biocenosis is;
What does artificial and natural biocenosis mean?

Word to the teacher:

We are all concerned about a serious question:
What is biocenosis?
I will solve this problem, friends, -
It's like this big family:
Animals and birds, beetles, spiders,
Forest, there are birches, aspens, oaks,
Worms and mice, air, earth,
Fallen leaves, maybe pine needles,
Even the path where you carried mushrooms,
This is what biocenosis is.

What do you think, based on the poem you read, what definition can be given to the concept of “biocenosis”?

Biocenosis is a community (totality) of plants, animals and other organisms.

There are 2 types (types) of biocenosis: natural and artificial (see slide 3). Try to determine what is the difference between these biocenoses. Give examples.

A natural biocenosis is one that nature created. For example, a lake, a forest.

An artificial biocenosis is one created by man. For example, a garden, a vegetable garden.

Natural biocenoses.

The composition of the inhabitants in each of them is not accidental; it depends on the conditions of the given territory and is adapted to them. Biocenoses can be rich in species and poor, for example: in the tundra there is a poor species composition, and in tropical forests– rich (see slides 4-7)

The higher the number of species, the more resistant the biocenosis is to various interventions.

The stability of biocenoses is also determined by their tiering - spatial and temporal (see slide 8).

What do you think these concepts mean?

Tiers - floors.

Spatial – located in space (triple dimension).

Temporal – located in time (changes over time)

Spatial layering (see slide 9) is characteristic of both animals and plants. Each tier is inhabited by individuals of its own species, but this does not prevent various animals from being in other tiers. However, the main stages of animal life take place in certain tiers. For example, bird nests are located in some tiers, and the search for food can occur in others.

If producers are organisms that produce a substance, then who are consumers?

! Consumers are those organisms that consume a substance.

Herbivores that create organic matter, but of animal origin, are called consumers of the first order (see slide 13).

So, we found out who the producers and consumers are. Think and tell me, who are decomposers and what role should they play?

! Decomposers are organisms that process the remains of dead animals and plants.

Decomposers are organisms that feed on the remains of dead plants and animals (see slide 14). These include bacteria, fungi and some animals, such as worms.

In a natural biocenosis, self-regulation of the number of individuals of each group occurs.

What features do you think the artificial biocenosis will have?

! Only what man has planted will grow there, and only a few species of animals will live.

Agriculture led to the destruction of natural and creation of artificial biocenoses (agrobiocenoses). Growing large areas of plants of the same species, for example, potatoes, wheat, led to a sharp reduction in connections between species. The agrobiocenosis is characterized by insignificant stability, because there is no tiering (both temporal and spatial).

Cultivated plants form a specific composition of the inhabitants of the animal world with a predominance of herbivorous species, mainly insect pests. All individuals are characterized by good adaptability to rapid changes in vegetation cover and omnivory.

To combat them, people use various methods, uses pesticides, polluting the environment, destroying both harmful and beneficial animals. To maintain the sustainability of artificial biocenoses, large financial costs are required.

For example, consider the biocenosis of a reservoir (see slide 16) .

Producers here are all types of plants, which in most cases are located in the upper layers. Microscopic algae form phytoplankton.

First order consumers are microscopic animals that form zooplankton, which feed on phytoplankton and directly depend on its development.

Second order consumers are fish that feed on crustaceans and insects.

Second order consumers are predatory fish.

Consumers can live at various depths, including at the bottom.

The remains of the vital activity of all organisms sink to the bottom and become food for decomposers, which decompose them into inorganic substances.

III. Physical exercise.

One two three four.
Biofamilies were studied
Learned a lot of new things
And a little tired.
We turn our eyes
Let's shake our heads.
Hands, legs pulled,
Take a good breath,
They leaned over once and twice.
Are you feeling dizzy?
Well, if everything is okay with you,
Let's work in a notebook.

IV. Consolidation of new material.

1. Work in a notebook (consolidating the concepts of “biocenosis”, “natural biocenosis”, “artificial biocenosis”).

RT. Page 132, no. 1, no. 2.

2. Independent work(working out concepts).

Strong students consider the biocenosis of a reservoir (work on sheets - templates).

Weak students watch the film “Ants” and answer questions (work on sheets - templates).

A certain time is given for work. After time has passed, students answer the questions posed (comment on the display of their material).

3. This is interesting.

Sheets (with different information) are distributed to students. After 2–3 minutes, you are asked to read out your 2 favorite facts.

Performing test tasks in the “Knowing” program. Students open the “Knowing” folder on the Desktop, select the “Biocenosis” test and begin testing.

IV. Lesson summary. Reflection. D/z.

All living nature that surrounds us - animals, plants, mushrooms and other living organisms - is a whole biocenosis or part, for example, of a regional biocenosis or the biocenosis of a separate part. All biocenoses have different conditions and may differ in the types of organisms and plants.

In contact with

Biocenosis is community, a set of living organisms in the nature of a certain territorial area. The concept also implies the conditions environment. If a separate territory is taken, then within its boundaries there should be approximately the same climate. The biocenosis can extend to the inhabitants of land, water and.

All organisms in the biocenosis are closely related to each other. There are food connections, or with the habitat and distribution. Some populations use others to build their own shelters.

There is also a vertical and horizontal structure of the biocenosis.

Attention! The biocenosis can be natural or artificial, that is, man-made.

In the 19th century, biology was actively developing, like other branches of science. Scientists continued to describe living organisms. In order to simplify the task of describing groups of organisms that inhabit a specific territory, Karl August Moebius was the first to introduce the term “biocenosis”. This happened in 1877.

Signs of biocenosis

There are the following signs of biocenosis:

There is a close relationship between the populations.
The biotic connection between all components is stable.
Organisms adapt to each other and in groups.
A biological cycle is observed in this area.
Organisms interact with each other, so they are mutually necessary.

Components

The components of a biocenosis are all living organisms. They are divided into three large groups:

consumers - consumers of finished substances (for example, predators);
producers - can produce nutrients independently (for example, green plants);
decomposers are those organisms that are the final link food chain, that is, they decompose dead organisms (for example, fungi and bacteria).

Components of biocenosis

Abiotic part of the biocenosis

Abiotic environment- this is climate, weather, relief, landscape, etc., that is, this is the inanimate part. Conditions will differ on different parts of the continents. The harsher the conditions, the fewer species will be present in the area. IN equatorial belt The most favorable climate is warm and humid, so endemic species are most often found in such areas (many of which can be found on the Australian mainland).

A separate area of the abiotic environment called a biotope.

Attention! The richness of species within the biocenosis depends on the conditions and nature of the abiotic environment.

Types of biocenosis

In biology, types of biocenosis are classified according to the following characteristics.

By spatial location:

Vertical (tiered);
Horizontal (mosaic).

By origin:

Natural (natural);
Artificial (man-made).

By connection type species within the biocenosis:

Trophic (food chains);
Factory (arrangement of habitats of an organism with the help of dead organisms);
Topical (individuals of one species serve as habitats or influence the lives of other species);
Phoric (participation of some species in the distribution of the habitat of others).

Spatial structure of the biocenosis

Natural biocenosis

Natural biocenosis is characterized by the fact that it has a natural origin. A person does not interfere with the processes occurring in it. For example: the Volga River, forest, steppe, meadow, mountains. Unlike artificial ones, natural ones have a larger scale.

If a person interferes with the natural environment, the balance between species is disrupted. Irreversible processes are taking place - the extinction and disappearance of some species of plants and animals, they are indicated in "". Those species that are on the verge of extinction are listed in the Red Book.

Let's look at examples of natural biocenosis.

River

The river is natural biocenosis. It is home to various animals, plants and bacteria. The views will vary depending on the location of the river. If the river is located in the north, then the diversity of the living world will be poor, but if it is closer to the equator, then the abundance and diversity of species living there will be rich.

Inhabitants of river biocenoses: beluga, perch, crucian carp, pike, sterlet, herring, ide, bream, pike perch, ruffe, smelt, burbot, crayfish, asp, carp, carp, catfish, roach, track, silver carp, sabrefish, various freshwater algae and many other living organisms.

Forest

Forest is example of a natural look. The forest biocenosis is rich in trees, shrubs, grass, animals that live in the air, on the ground and in the soil. Here you can find mushrooms. Various bacteria also live in the forest.

Representatives of the forest biocenosis ( animal world): wolf, fox, elk, wild boar, squirrel, hedgehog, hare, bear, elk, tit, woodpecker, chaffinch, cuckoo, oriole, black grouse, wood grouse, thrush, owl, ant, ladybug, pine silkworm, grasshopper, tick and many other animals.

Representatives of the forest biocenosis ( vegetable world): birch, linden, maple, elderberry, corydalis, oak, pine, spruce, aspen, lily of the valley, kupir, strawberry, blackberry, dandelion, snowdrop, violet, forget-me-not, lungwort, hazel and many other plants.

The forest biocenosis is represented by the following mushrooms: boletus, boletus, White mushroom, toadstool, fly agaric, oyster mushroom, puffball, chanterelle, oiler, honey fungus, morel, russula, champignon, saffron milk cap, etc.

Natural and artificial biocenosis

Artificial biocenosis

An artificial biocenosis differs from a natural one in that it created by human hands to satisfy their needs or the needs of the whole society. In such systems, a person himself designs the required conditions. Examples of such systems are: garden, vegetable garden, field, forest plantation, apiary, aquarium, canal, pond, etc.

The emergence of artificial environments led to the destruction of natural biocenoses, the development Agriculture and the agricultural sector of the economy.

Examples of artificial classification

For example, in a field, greenhouse, garden or vegetable garden, a person grows cultivated plants (vegetables, grain crops, fruitful plants, etc.). So that they don't die, certain conditions are created: Irrigation systems for watering, lighting. The soil is saturated with the missing elements with the help of fertilizers. Plants are treated with chemicals to protect them from being eaten by pests, etc.

Forest belts are planted near fields, on the slopes of ravines, near railways and roads. Near the fields they are needed in order to reduce evaporation and retain snow in the spring, i.e. to control the water regime of the earth. Trees also protect seeds from being blown away by the wind and protect the soil from erosion.

Trees are planted on the slopes of ravines in order to prevent and slow down their growth, since the roots will hold the soil.

Trees along roads are necessary to prevent snow, dust, and sand from driving transport routes.

Attention! Man creates artificial biocenoses in order to improve the life of society. But excessive interference with nature is fraught with consequences.

Horizontal structure of biocenosis

The horizontal structure of a biocenosis differs from the tiered one in that the abundance of species living on its territory changes not vertically, but horizontally.

For example, we can consider the most global example. The diversity, abundance and richness of the living world varies by zone. In the zone arctic deserts, in the Arctic climatic zone, the flora and fauna are sparse and poor. As we approach the tropical forest zone, in the tropical climate zone, the number and diversity of species will increase. So we were able to trace changes in the number of species within the biocenosis, and even changes in their structure (since they have to adapt to different climate conditions). This is a natural mosaic.

And artificial mosaic occurs under human influence on the environment. For example, deforestation, sowing meadows, draining swamps, etc. In a place where people have not changed the conditions, the organisms will remain. And those places where conditions have changed will be inhabited by new populations. The components of the biocenosis will also differ.

Biocenosis

The concept of biogeocenosis and ecosystem

Conclusion

Let's summarize: biocenosis has different classifications depending on its origin, relationships between organisms and location in space. They differ in territorial scale and the species that live within their boundaries. Signs of biocenosis can be classified separately for each area.

K. Mobius and G.F. Morozov formulated rule of mutual adaptation, Whereby species in a biocenosis are so adapted to each other that their community constitutes an internally contradictory, but unified and mutually interconnected whole . In other words, in natural biocenoses there are no beneficial and harmful birds, beneficial and harmful insects; there everything (even predators like the wolf) serves each other and is mutually adapted.

At the same time, changes that for one reason or another (for example, due to changes climatic conditions) arise in biocenoses and influence their stability in different ways. So, if one species displaces another, then significant changes in the biocenosis will not occur, especially in the case when this species is not among the mass species. Therefore, when replacing one predator (marten) in the forest with another (sable), which is able to obtain food for itself both on the ground and in trees, the forest biocenosis will retain all its main features.

In case of loss of rare and small species, the main biocenotic connections do not change significantly until a certain time. Thus, a spruce forest near a city can survive for a relatively long time and even renew itself despite constant anthropogenic pressure and the resulting disappearance of many species of plants, birds, and insects. However, the species composition of such forests is gradually becoming poorer, and their stability is weakening. Such a weakened, depleted biocenosis can collapse unnoticed, for example, due to the depletion of mineral nutrition reserves by trees, as well as due to a sudden and massive attack by pests. The basis for the stability of biocenoses is their complex species composition.

In cases where the main species - environment-formers - drop out of the biocenosis, this leads to the destruction of the entire system and a change in communities. Sometimes such changes in nature are made by humans by cutting down forests, overfishing in water bodies, etc.

In fairness, it is necessary to point out that the sudden “landslide” destruction of previously stable communities is a property inherent in all complex systems in which internal connections have gradually weakened. Identifying these patterns is extremely important both for creating artificial communities and maintaining natural biocenoses. Thus, if it is necessary to restore forests, steppes, or establish forest parks, they try to create a complex species and spatial structure of communities, for which they select species of organisms that complement each other and get along together.

Dynamism- this is one of the main properties of biocenoses. Long-term observation of an abandoned field shows that it is successively conquered first by perennial grasses, then by shrubs and, finally, by woody vegetation.

Any biocenosis depends on its biotope and, conversely, every biotope is influenced by the biocenosis. Since climatic, geological and biotic factors are subject to change, the development or dynamics of biocenoses is simply inevitable. Another thing is that in each specific case it occurs at different speeds.

The influence that a biotope has on the biocenosis is called share. Manifesting itself in a very diverse manner, for example, through the influence of climate, it can cause a variety of consequences: morphological, physiological and ecological adaptations, the preservation or extinction of species, as well as the regulation of their numbers.

The influence exerted, in turn, by the biocenosis on the biotope is called reaction. The latter can be expressed in the destruction, creation or change of the biotope. There are many examples of destructive reactions caused by plants. Mosses and lichens settle on a wide variety of rocks. The roots of higher plants enlarge the crevices formed in these rocks and, in addition, have a chemical effect with acidic secretions. Many marine invertebrates (molluscs, sea urchins, sponges) “drill” into rocks. Digging animals mix the soil to a considerable depth. Wherein main role play here earthworms and termites.

On the contrary, the creative reaction in terrestrial conditions is expressed in the accumulation of animal (corpses) and plant (fallen leaves) residues, which, due to a series of chemical changes (bacterial decay), gradually turn into humus. Finally, biocenoses transform the local climate, creating a microclimate.

A review of various interactions between biocenoses and biotopes shows that the main reasons that cause the development of biocenoses are climatic, geological, edaphic (soil) and biotic factors.

The level of impact of climatic factors can be assessed using the example of the changes that occurred in Europe during the glacial and interglacial periods. Then, in the Quaternary period, with the maximum advance of the glacier, Central Europe was a tundra with dwarf willows, dryads and saxifrage, and all the flora of the temperate climate was forced to the extreme south. The fauna of that time included mammoths, hairy rhinoceroses, musk oxen and small rodents. The warming that occurred during interglacial periods contributed to the return of grapes to the areas north of the Alps, and the “heat-loving fauna”, incl. the ancient elephant and hippopotamus managed to settle in Europe.

As for geological phenomena (erosion, sedimentation, mountain building and volcanism), they can also greatly change the biotope, which, in turn, will cause significant shifts in biocenoses. The ongoing development of soils (edaphic factors), which is determined by the combined action of climate and living organisms, entails in parallel the development of flora.

Biological factors are the most common and fastest-acting factors. One can point out, for example, the role of bison, whose number previously amounted to tens of millions of heads, in the development of biocenoses of the American prairies. An environmental factor such as interspecific competition also plays a huge role in this process.

Currently, the determining factor in the development of biocenoses is economic, as well as military activities person. Fires, deforestation, construction of roads, pipelines, rocket launches, introduction (conscious or accidental) of new species of animals (especially microorganisms) or plants are just some examples of human invasion of nature. They can lead to the rapid evolution of biocenoses, and sometimes to the extinction of certain species of organisms.

Question 6. What are the reasons for migrations? Give examples.

The reasons for migration are changes in the living conditions of animals. Examples include the migration of birds, locusts to places where there is enough food, etc.
^ 53. Natural and artificial biocenoses

Question 1 Prove that spatial and temporal tiers increase the stability of the biocenosis.

Spatial and temporal tiering allows a large number species coexist in the same territory, as it ensures a wider use of light, heat, moisture and thereby reduces competition. And a community with greater species diversity has a greater ability to adapt to changing living and inanimate nature, i.e. higher stability.

Question 2. Give examples known to you that confirm the presence of temporal or spatial tiers in animals.
An example of spatial tiering in animals is the distribution of nesting sites in birds. There are bird species that nest on the ground (chickens, grouse, buntings, pipits, etc.), in the bush layer (bullfinches, warblers, nightingales, song thrushes, etc.), in the crowns of trees (crests, goldfinches, finches, etc.) .

Temporal layering is illustrated by different calendar dates of nesting. For example, finches hatch chicks in the spring, and crossbills hatch in winter.

Question 3. Why are there consumers of the second and more orders, but no producers of the second order?

Producers are organisms that produce primary organic substances from inorganic ones. For example, plants use the energy of the sun to produce them from carbon dioxide and water. Therefore, there cannot be second order producers. All of them belong to the first trophic level.

Consumers are consumers of organic substances. They can be divided into herbivores and carnivores, i.e., classified as order I and II.

Question 4. Why are cases of mass reproduction of pests observed in natural biocenoses much less often than in artificial ones?

This is explained by the fact that in natural biocenoses the species composition and relationships between species are balanced. The introduction of a foreign species into a stable system of natural biocenosis and its mass reproduction is difficult. In an artificial biocenosis, the laws of interaction between species are directionally violated (to obtain high productivity of one species) and there are no natural barriers to the mass reproduction of pests.

^ 54. Environmental factors and their influence on biocenoses

Question 1 . What local examples can you confirm the direct and indirect influence of biotic factors?

The impact of biotic factors can be direct and indirect.

Typical examples of direct influence are food connections. For example, owls directly regulate the number of mouse-like rodents by feeding on them.

Indirect influence occurs when animals of a given species are expelled from burrows or other habitats, when their food supply is destroyed, or when there is constant disturbance. For example, a poor grass harvest in a dry summer indirectly affects the state of the owl population, since in such conditions fewer mouse-like rodents, which are food for owls, survive.

Question 2. Prove that moles change their habitat.

Moles change the state of the soil environment in which they live by creating a system of underground passages and periodically throwing soil to the surface in the form of molehills. As a result, the aeration of the soil changes and its layers are mixed.

Question 3. Give examples of the positive and negative impact of humans on nature as a result of economic activity.

Artificial breeding, protection of certain species of rare animals and

plants can serve as a positive example.

There are much more negative examples. This includes the destruction of natural biocenoses when using land for economic needs, and pollution of the environment with huge amounts of waste from industrial enterprises, many of which are toxic and lead to the death of land, soil and aquatic inhabitants, and, finally, the direct extermination of many plants and animals that are objects of fishing .

^ 55. Power circuits. Energy flow

Question 1 What does the length of the power chain indicate?

The food chain usually cannot consist of more than 4-6 links, including organisms that consume animal corpses, which is explained by the loss of energy at each level (in each link). The length of the power chain indicates the efficiency of energy use in its links (the more fully the energy is used, the longer the chain).

Question 2. Why is the number (number of species) of consumers in the food chain decreasing?

In the food chain, each subsequent link loses part of the organic matter -

va obtained from food, and part of the energy extracted from it. Only 10% of the total mass of food eaten is digested. Therefore, the transition from one link to another is accompanied by a sharp reduction in the number of consumers in the food chain. If the number of predators is greater than the number of their prey, they will destroy their entire food supply and themselves will begin to die of starvation.

Question 3. How do nature users determine the productivity of a natural biocenosis?

Nature users evaluate the productivity of a natural biocenosis by quantitative indicators, using biomass pyramids (food pyramids, energy pyramids).

Question 4. What is your opinion about the productivity of natural and artificial biocenoses on the same territory? Justify your answer.

Pyramids of biomass, or food, and energy make it possible to assess the productivity of a biocenosis and the possibility of using part of the biomass for human needs. Comparing natural and artificial biocenoses in terms of productivity, we can say that the primary productivity of an artificial biocenosis (agrocenosis) is higher than

than natural. As for the next steps of the pyramid, agrocenoses, as a rule, do not have animal consumers of the second order and higher, since their place is taken by humans. Considering that it is necessary to spend certain resources, including energy, to combat natural consumers (for humans - agricultural pests), the question of management efficiency arises.

^ 56. The relationship between the components of the biocenosis and their adaptability to each other

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 activity, produce primary organic substances under the influence of light 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, aquariums contain predatory fish that 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, the work of cleaning organic waste in the biocenosis of the aquarium is performed by humans.

Question 3. Prove that in an aquarium you can demonstrate 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 mineral nutrition to the plants; 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.
^ 57. Impact of humans and their activities on animals

Question 1 . Use local examples to show that human impacts on habitats have greater consequences than the extermination of a species.

To answer this question, it should be noted that there are very few species in nature whose functions in biocenoses could not be taken over by representatives of other species. The negative impact of humans on the environment, as a rule, is complex in nature, since it affects all organisms living in a given territory. For example, drainage of swamps, plowing of virgin lands, and deforestation lead to a sharp reduction in the ranges of wild ungulates. Following them, the number of predators decreases, and the number of rodents increases.

There is a complete, irreversible destruction of the biocenosis.

Question 2. What can the residents of your area be proud of in terms of wildlife conservation, and what should they be ashamed of?

We can be proud that many environmental technologies have already been created (for wastewater treatment, recycling industrial waste, neutralization of pesticides, etc.) and new, more and more advanced ones continue to be developed; a methodology for the conservation and captive breeding of endangered animals has been developed; there is positive experience in restoring the numbers of specific animal species (for example, bison, bison, beavers, etc.) in protected areas.

And it is unforgivable when we do not apply these developed methods and technologies for environmental protection in all cases where it is necessary.

Question 3. Are there any fisheries in your area? Are they effective? Justify your answer with calculations.

By trade refers to the removal of animals from nature by humans through the capture of prey. Trades differ by the name of the group of animals or the products of their vital activity, for example: fur trade, fishing, bee farming, fishing for crabs, oysters, sea cucumbers, pearl mussels, etc. There are groups of animals that are considered commercial. In each locality one can name examples of commercial fish, birds and animals.

Let's look at the efficiency of fishing using the example of recreational fishing.

Let’s assume that the family’s costs are mainly related to the purchase of gear and transportation costs and amount to about 15% of the cost of the fish caught. If on average a family consumes 45 kg of fish per year (the average price of 1 kg is 40 rubles), then by providing themselves with the caught fish, they will save 1,530 rubles.

Question 4. What is poaching? What is its harm?

Poaching - hunting or destruction of wild animals in violation of current laws regulating animal hunting, as well as the requirements of legislation on the protection of wildlife.

Poaching leads to the unregulated capture of game animals on a scale that does not take into account the possibilities of their natural restoration, and also negates efforts to preserve rare species in nature.

^ 58. Domestication of animals

Question 1 . Which ways of domesticating animals seem more reliable to you?

To date, several routes of domestication have been proposed. Each of them can be considered reliable. Firstly, animals were caught during the hunt, and then kept on a leash or in a pen, gradually tamed. Secondly, they tamed the cubs left alive after the hunt. Hunters gave them as toys to children, who looked after their pets, fed them, and played together. Thirdly, in some cases, domestication was facilitated by religious veneration of the animal and, as a consequence, its inviolability (for example, cows in India, cats in Egypt).

Question 2. Why is the domestication process so slow?

It can be assumed that the duration of the domestication process is due to the fact that the first domestic animals appeared in humans by chance. Knowledge had to be accumulated about the peculiarities of their way of life and experience in successfully keeping and breeding them in captivity. Then there was a long selection of animals with traits useful to humans.

Question 3. Prove that domesticated animals are more productive than their wild relatives.

The body weight of wild geese is 5-6 kg, domestic geese - up to 12 kg. The egg production of wild chickens is from 6 to 16 eggs per year, domestic chickens - up to 40 eggs per year.

Question 4. What areas of selection of pets do you know? Give examples from your area.

Most often, selection is carried out to obtain products from a given animal. For example, in birds it is usually carried out in two directions: for egg production and for rapid growth - increasing large body weight. In sheep, selection is carried out in several directions: to increase the number of lambs; for increasing body weight - meat, meat and fat breeds; for fleece or milk. In cattle, selection is carried out for milk production, body weight and early maturity.

^ 59. Laws of Russia on the protection of wildlife. Monitoring system

Question 1 For what purpose do countries pass laws to protect wildlife?

Laws on the protection of wildlife are adopted in order to regulate the relationship between the protection and use of wildlife, its habitat, and preserve biological diversity.

Question 2. Why is international cooperation on environmental monitoring necessary?

Environmental pollution has become planetary. The international cooperation on environmental monitoring issues is necessary because in nature there are no boundaries in the state understanding of the word. Thanks to monitoring at the international level, it is possible to obtain more complete and reliable information about the state of the environment.

Question 3. What reasons, other than poaching, can explain the decline in the numbers of some game animals in 1995?

A decrease in the number of game animals is observed annually. In addition to poaching, this is due to the fact that the habitats of these animals are being destroyed due to environmental pollution, as well as as a result of human development of these territories for various objects (construction of roads, buildings, etc.).

Question 4. Do you need monitoring of your territory? Justify your answer.

Monitoring are called observation, assessment and forecast of the state of the environment in connection with human economic activities. Monitoring is appropriate in any territory - with a developed economic structure and a protected area. The more widely it is carried out, the more complete data on the dynamics of the state of the environment we have.
^ 60. Protection and rational use of wildlife

Question 1 What types of protected areas do you know?

In order to preserve natural landscapes as habitats for numerous wild animals in our country, territories with varying degrees of protection are defined by law. These are nature reserves, sanctuaries, natural monuments, National parks. All of them constitute a system of reference, specially protected territories and objects.

Question 2. What objects in your area do you consider necessary to protect?

In the context of human economic activity, any natural objects require protection. Particular attention should be paid to those objects that have not yet been disturbed, and they should be given the status of specially protected areas. The remaining objects should be restored and their maximum preservation should be strived for.

Question 3. Is there a Red Book for the area where you live? What do you know about her?

The International Red Book was established by the decision International Union nature conservation and natural resources(IUCN) in 1966. In 1980, the Red Book of the USSR was established, in 1982 - the Red Book of the RSFSR. Currently there is a Red Book of Russia. All Red Books are built according to the same plan - these are lists of animal species in five categories: endangered; declining in numbers; rare; little-studied; restored.

The main goals of the Red Book are to attract the attention of humanity to saving endangered species and restoring rare ones, to unite the efforts of all interested individuals and organizations in saving animals and preserving their species diversity.

Question 4. Why is it necessary to periodically review and republish the Red Books?

Depending on the environmental measures taken by humanity, the status of a particular biological species in the Red Book may change. Therefore, the Red Books must be periodically revised and republished.

Question 5. What does sustainable animal management mean?

Animal stewardship involves obtaining maximum benefit from them while maintaining their existing numbers and biological diversity.