Environmental factors. Limiting factor

Environmental factors always act on organisms in combination. Moreover, the result is not the sum of the influence of several factors, but is difficult process their interactions. At the same time, the vitality of the organism changes, specific adaptive properties arise that allow it to survive in certain conditions and tolerate fluctuations in the values ​​of various factors. The influence of environmental factors on the body can be represented in the form of a diagram ().

The most favorable intensity of the environmental factor for the body is called optimal or optimum.

Deviation from the optimal action of the factor leads to inhibition of the body’s vital functions.

The limit beyond which the existence of an organism is impossible is called endurance limit.

These boundaries are different for different types and even for different individuals of the same species. For example, the upper layers of the atmosphere, thermal springs, and the ice desert of Antarctica are beyond the limits of endurance for many organisms.

An environmental factor that goes beyond the limits of the body's endurance is called limiting.

It has upper and lower limits. So, for fish the limiting factor is water. Outside the aquatic environment, their life is impossible. A decrease in water temperature below 0 °C is the lower limit, and an increase above 45 °C is the upper limit of endurance.

Scheme of the action of an environmental factor on the body
Thus, the optimum reflects the characteristics of living conditions various types. In accordance with the level of the most favorable factors, organisms are divided into heat- and cold-loving, moisture-loving and drought-resistant, light-loving and shade-tolerant, adapted to life in salt and fresh water, etc. The wider the limit of endurance, the more plastic the organism. Moreover, the limit of endurance in relation to various environmental factors varies among organisms. For example, moisture-loving plants can tolerate large temperature changes, while the lack of moisture is detrimental to them. Narrowly adapted species are less plastic and have a small limit of endurance, widely adapted species are more plastic and have large range fluctuations in environmental factors. For fish living in the cold seas of Antarctica and the Arctic Ocean, the temperature range is 4–8 °C. As the temperature rises (above 10 °C), they stop moving and fall into thermal stupor. On the other hand, fish from equatorial and temperate latitudes tolerate temperature fluctuations from 10 to 40 °C. Warm-blooded animals have a wider range of endurance. Thus, arctic foxes in the tundra can tolerate temperature changes from -50 to 30 °C. Temperate plants tolerate temperature fluctuations of 60–80 °C, while tropical plants have a much narrower temperature range: 30–40 °C. Interaction of environmental factors is that changing the intensity of one of them can narrow the limit of endurance to another factor or, conversely, increase it. For example, optimal temperature increases tolerance to lack of moisture and food. High humidity significantly reduces the body's resistance to high temperatures. The intensity of exposure to environmental factors is directly dependent on the duration of this exposure. Long lasting high or low temperatures are detrimental to many plants, while plants tolerate short-term changes normally. The limiting factors for plants are the composition of the soil, the presence of nitrogen and other nutrients in it. Thus, clover grows better in soils poor in nitrogen, and nettle does the opposite. A decrease in nitrogen content in the soil leads to a decrease in the drought resistance of cereals. Plants grow worse on salty soils; many species do not take root at all. Thus, the organism’s adaptability to individual environmental factors is individual and can have both a wide and narrow range of endurance. But if the quantitative change in at least one of the factors goes beyond the limit of endurance, then, despite the fact that other conditions are favorable, the organism dies.

The set of environmental factors (abiotic and biotic) that are necessary for the existence of a species is called ecological niche.

An ecological niche characterizes the way of life of an organism, its living conditions and nutrition. In contrast to a niche, the concept of habitat denotes the territory where an organism lives, i.e. its “address”. For example, the herbivorous inhabitants of the steppes, cows and kangaroos, occupy the same ecological niche, but have different habitats. On the contrary, the inhabitants of the forest - squirrel and elk, also classified as herbivores, occupy different ecological niches. The ecological niche always determines the distribution of an organism and its role in the community.

The body is simultaneously influenced by numerous diverse and multidirectional environmental factors. In nature, the combination of all influences in their optimal, most favorable values ​​is practically impossible. Therefore, even in habitats where all (or leading) environmental factors are most favorably combined, each of them most often deviates somewhat from the optimum. To characterize the action of factors external environment in animals and plants, it is essential that in relation to certain factors, organisms have a wide range of endurance and can withstand significant deviations in the intensity of the factor from the optimal value.

Organisms are adapted to other factors only within a narrow range of changes and can withstand only small deviations from the optimum. For example, some cold-adapted Antarctic fish species have a temperature tolerance range of only 4 °C (-2 to +2 °C). As the temperature rises to 0 °C, metabolic activity increases, but with a further increase, the metabolic intensity drops and at +1.9 °C the fish stop moving, falling into thermal stupor. Animals living in high latitudes have a wide range of tolerance to temperature fluctuations. Thus, arctic foxes in the tundra can tolerate temperature fluctuations within 80 °C (from +30 to -55 °C). Siberian plants are resistant to cold. For example, Daurian larch near Verkhoyansk can withstand winter frosts down to -70 °C. Plants of tropical forests can exist within rather narrow limits of temperature change: its decrease to +5...+8 °C has a detrimental effect on them.

In relation to environmental factors, species are distinguished between heat-loving and cold-loving, moisture- and dry-loving, adapted to high or low salinity of water. For aquatic animals great importance has the concentration of oxygen in water. Some species can only exist within narrow ranges of oxygen content fluctuations. Juvenile brook trout develop well at an oxygen concentration of 2 mg/l; when it decreases to 1.6 mg/l, all trout die. Other fish species - catfish, carp, adapted to living in stagnant waters, tolerate low oxygen levels well.

At different stages of ontogenesis, organisms may exhibit unequal tolerance to one or another factor. For example, the mill moth, one of the pests of flour and grain products, has a critical minimum temperature for caterpillars of -7 °C, for adult forms -22 °C, and for eggs -27 °C. Frost - 10 °C will kill the caterpillars, but will be harmless to eggs and adult forms.

Deviation of the intensity of one factor from the optimal value can narrow the limits of resistance to another factor. Thus, with a decrease in nitrogen content in the soil, the drought resistance of cereals decreases. A factor that is in deficiency or excess compared to the optimal value is called limiting, since it makes it impossible for the species to flourish under given conditions. The existence of limiting factors was first pointed out by the German chemist J. Liebig (1840). The nature of these factors is different: lack of a chemical element in the soil, lack of heat or moisture. Biotic relationships can also be limiting factors for distribution: occupation of territory by a stronger competitor or lack of pollinators for plants (Fig. 25.6). For the distribution of species, two indicators are of great importance: the temperature threshold for development and the sum of effective temperatures.

Many factors become limiting during the breeding season. Hardiness limits for seeds, eggs, embryos, and larvae are usually narrower than for adult plants and animals. For example, many crabs can enter rivers far upstream, but their larvae cannot develop in river water. The range of game birds is often determined by the effects of climate on eggs or chicks rather than on adults.

Identifying limiting factors is very important in practical terms. Thus, wheat does not grow well in acidic soils, but adding lime to the soil can significantly increase yields.

Rice. 25.6. Liebig barrel. The factor in the deficiency (lowest hole)

is limiting

Anchor points

• Of the many environmental factors that influence the body, only a few are characterized by optimal values ​​for life.
• Animals and plants, fungi and prokaryotes acquire adaptations to living conditions in the process of evolution.

Questions and tasks for review

• 1. What is called a narrow and wide range of endurance of organisms?
• 2. What do the terms “cold-tolerant” and “heat-loving” organisms indicate?
• 3. What is the sum of effective temperatures?
• 4. Explain how the limiting effect of an environmental factor can manifest itself.
• 5. Why do you think the adaptation of living organisms to abiotic environmental conditions cannot be endless?
• 6. Based on knowledge about the interaction of environmental factors and the limiting factor, try to create a model of artificial agricultural production for growing cultivated plants during the whole year.

Environmental factors always act on organisms in combination. Moreover, the result is not the sum of the influence of several factors, but is a complex process of their interaction. At the same time, the vitality of the organism changes, specific adaptive properties arise that allow it to survive in certain conditions and tolerate fluctuations in the values ​​of various factors.

The influence of environmental factors on the body can be represented in the form of a diagram (Fig. 94).

The most favorable intensity of the environmental factor for the body is called optimal or optimum.

Deviation from the optimal action of the factor leads to inhibition of the body’s vital functions.

The limit beyond which the existence of an organism is impossible is called endurance limit.

These boundaries are different for different species and even for different individuals of the same species. For example, the upper layers of the atmosphere, thermal springs, and the ice desert of Antarctica are beyond the limits of endurance for many organisms.

An environmental factor that goes beyond the limits of the body's endurance is called limiting.

It has upper and lower limits. So, for fish the limiting factor is water. Outside the aquatic environment, their life is impossible. A decrease in water temperature below 0 °C is the lower limit, and an increase above 45 °C is the upper limit of endurance.

Rice. 94. Scheme of the action of an environmental factor on the body

Thus, the optimum reflects the characteristics of the living conditions of various species. In accordance with the level of the most favorable factors, organisms are divided into heat- and cold-loving, moisture-loving and drought-resistant, light-loving and shade-tolerant, adapted to life in salt and fresh water, etc. The wider the limit of endurance, the more plastic the organism. Moreover, the limit of endurance in relation to various environmental factors varies among organisms. For example, moisture-loving plants can tolerate large temperature changes, while the lack of moisture is detrimental to them. Narrowly adapted species are less plastic and have a small limit of endurance; widely adapted species are more plastic and have a wide range of fluctuations in environmental factors.

For fish living in the cold seas of Antarctica and the Arctic Ocean, the range of tolerated temperatures is 4-8 °C. As the temperature rises (above 10 °C), they stop moving and fall into thermal stupor. On the other hand, fish from equatorial and temperate latitudes tolerate temperature fluctuations from 10 to 40 °C. Warm-blooded animals have a wider range of endurance. Thus, arctic foxes in the tundra can tolerate temperature changes from -50 to 30 °C.

Temperate plants can withstand temperature fluctuations of 60-80 °C, while tropical plants have a much narrower temperature range: 30-40 °C.

Interaction of environmental factors is that changing the intensity of one of them can narrow the limit of endurance to another factor or, conversely, increase it. For example, optimal temperature increases tolerance to lack of moisture and food. High humidity significantly reduces the body's resistance to high temperatures. The intensity of exposure to environmental factors is directly dependent on the duration of this exposure. Long-term exposure to high or low temperatures is detrimental to many plants, while plants tolerate short-term changes normally. The limiting factors for plants are the composition of the soil, the presence of nitrogen and other nutrients in it. So, clover grows better in soils poor in nitrogen, and nettle does the opposite. A decrease in nitrogen content in the soil leads to a decrease in the drought resistance of cereals. Plants grow worse on salty soils; many species do not take root at all. Thus, the organism’s adaptability to individual environmental factors is individual and can have both a wide and narrow range of endurance. But if the quantitative change in at least one of the factors goes beyond the limit of endurance, then, despite the fact that other conditions are favorable, the organism dies.

The set of environmental factors (abiotic and biotic) that are necessary for the existence of a species is called ecological niche.

An ecological niche characterizes the way of life of an organism, its living conditions and nutrition. In contrast to a niche, the concept of habitat denotes the territory where an organism lives, i.e. its “address”. For example, the herbivorous inhabitants of the steppes, cows and kangaroos, occupy the same ecological niche, but have different habitats. On the contrary, the inhabitants of the forest - squirrel and elk, also classified as herbivores, occupy different ecological niches. The ecological niche always determines the distribution of an organism and its role in the community.

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§ 67. Impact of certain environmental factors on organisms§ 69. Basic properties of populations

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Limiting factors can include any environmental factors: lighting, temperature, humidity, microenvironment, soil composition, etc. The doctrine of limiting factors is based on two fundamental postulates: Liebig's law (1840) and Shelford's law (1913).

Each species of plants, microorganisms and animals exists in conditions under which their life is most comfortable. In order for representatives of each population to be able to fully feed, develop and reproduce, it is necessary for each environmental factor to correspond to certain values ​​that fall within a more or less wide range. This applies to insects to the same extent as to other living organisms, so in the future we will consider the influence of limiting factors using the example of this class.

For the viability of organisms, both a decrease and an excess of optimal values ​​of temperature, humidity, etc. are dangerous. Exceeding their endurance limits leads to the death of an organism, a population or even an ecosystem.

For example, if the soil lacks a certain microelement, this causes a decrease in plant productivity. Due to the lack of food, the insects that fed on these plants die. The latter, in turn, affects the survival of entomophagous predators: other insects, birds, some amphibians, etc.

Each organism is characterized by a certain ecological minimum and maximum, between which there is a zone of normal life activity (or optimum). The further a factor deviates from the optimum value, the more noticeable it is. negative impact. Beyond critical points (extreme values ​​of the limiting factor), the existence of an organism is impossible.

To indicate the degree of tolerance (resistance) of species to different meanings limiting factors, they are usually divided into low-hardy - stenobionts- and hardy, or eurybionts. Stenobionts include lower insects that live in caves (Bessyazhkovye, etc.), as well as most tropical orders that exist only in conditions of high temperature and humidity. For example, Lepidoptera of the order Morpho (photo) live only in the dense tropical forests of Central and South America and are very poorly bred in artificial conditions. In particular, they are very picky about the light regime: each species of these butterflies flies only at a certain time of the day.

Limiting factors of inanimate nature

Among all abiotic factors insects are most sensitive to temperature, light and humidity.

As for the first, on the territory of our country, most species are able to live in the temperature range from 3 to 40 degrees, although some have adaptation mechanisms that allow them to exist outside the zone of normal life activity. Thus, a number of highly developed insects show resistance to freezing, since the liquid in their body does not turn into crystals, but vitrifies - it becomes like glass. It is common among some beetles, Lepidoptera and Diptera. For example, swallowtail butterflies (photo) can tolerate deep freezing down to almost -200 degrees.

Lighting is also important. Under the influence of optimal doses of ultraviolet radiation, important biochemical processes occur in the body of insects: the release of hormones, the formation of pigment, and even the absorption of certain minerals. Adherence to a certain light regime determines their lifestyle (day, night), as well as their preferred habitat. Thus, click beetles living in the soil cannot tolerate bright light and die under the influence of intense ultraviolet radiation.

Such a limiting factor as humidity affects insects very differently. Some of them, for example, mosquitoes, midges or primitive orders like mayflies, live mainly near bodies of water, which are associated not only with the most comfortable conditions for their life, but also with the process of life. For this reason, draining swamps is one of the most effective methods of controlling the spread of mosquitoes. Among insects there are also xerophytes that prefer arid areas, for example, ants inhabiting semi-deserts.

Limiting factors of wildlife

The life activity of insects can be limited not only by inanimate natural phenomena, but also by factors of biological origin. Biological limiting factors in the form of predators threaten all herbivorous species: for example, for butterflies, even within a class, dozens of predators can pose a threat, from mantises and ants to lacewings and some grasshoppers.

Under normal conditions, each species and population strives to occupy its own ecological niche, but sometimes conditions arise that two or more species compete with each other. In this case, they become limiting factors for each other. Most often, competition develops due to a lack of food resources; It often occurs between flying insects that pollinate the same plants.

U social forms- ants and termites - competition is noticeable not only outside the species, but also within it. These insects live in autonomous colonies, and each family poses a potential threat to every other by destroying available food and occupying its potential home.

In this work I will cover in detail the topic “Limiting factors”. I will consider their definition, types, laws and examples.

Different environmental factors have different significance for living organisms.

For organisms to live, a certain combination of conditions is necessary. If all environmental conditions are favorable, with the exception of one, then this condition becomes decisive for the life of the organism in question.

Of the variety of limiting environmental factors, the attention of researchers is primarily attracted to those that inhibit the vital activity of organisms and limit their growth and development.

Main part

In the total pressure of the environment, factors are identified that most strongly limit the success of the life of organisms. Such factors are called limiting or limiting.

Limiting factors - This

1) any factors inhibiting population growth in the ecosystem; 2) environmental factors, the value of which greatly deviates from the optimum.

In the presence of optimal combinations of many factors, one limiting factor can lead to oppression and death of organisms. For example, heat-loving plants die at negative air temperatures, despite the optimal content of nutrients in the soil, optimal humidity, light, and so on. Limiting factors are irreplaceable if they do not interact with other factors. For example, a lack of mineral nitrogen in the soil cannot be compensated for by an excess of potassium or phosphorus.

Limiting factors for terrestrial ecosystems:

Temperature;

Nutrients in the soil.

Limiting factors for aquatic ecosystems:

Temperature;

Sunlight;

Salinity.

Typically, these factors interact in such a way that one process is limited simultaneously by several factors, and a change in any of them leads to a new equilibrium. For example, an increase in food availability and a decrease in predation pressure can lead to an increase in population size.

Examples of limiting factors are: outcrops of uneroded rocks, erosion base, valley sides, etc.

Thus, the factor limiting the spread of deer is the depth of the snow cover; moths of the winter armyworm (a pest of vegetable and grain crops) - winter temperature, etc.

The idea of ​​limiting factors is based on two laws of ecology: the law of the minimum and the law of tolerance.

Law of the minimum

In the mid-19th century, the German organic chemist Liebig, studying the effect of various microelements on plant growth, was the first to establish the following: plant growth is limited by an element whose concentration and significance is at a minimum, that is, present in a minimal amount. The so-called “Liebig barrel” helps to represent the law of the minimum figuratively. This is a barrel with wooden slats of different heights, as shown in the figure. It is clear that no matter what the height of the other slats, you can pour exactly as much water into the barrel as the height of the shortest slats. Likewise, a limiting factor limits the life activity of organisms, despite the level (dose) of other factors. For example, if yeast is placed in cold water, low temperature will become a limiting factor in their reproduction. Every housewife knows this, and therefore leaves the yeast to “swell” (and actually multiply) in warm water with a sufficient amount of sugar.

Heat, light, water, oxygen, and other factors can limit or limit the development of organisms, if their movement corresponds to the ecological minimum. For example, the tropical fish angelfish dies if the water temperature drops below 16 °C. And the development of algae in deep-sea ecosystems is limited by the depth of penetration of sunlight: there are no algae in the bottom layers.

Later (in 1909), the law of the minimum was interpreted by F. Blackman more broadly, as the action of any ecological factor that is at a minimum: environmental factors that have the worst significance in specific conditions especially limit the possibility of the existence of a species in these conditions in spite of and in spite of optimal combination of other hotel conditions.

In its modern formulation, the law of the minimum sounds like this: the body's endurance is determined by the weakest link in the chain of its environmental needs .

To successfully apply the law of limiting factors in practice, two principles must be observed:

The first is restrictive, that is, the law is strictly applicable only under stationary conditions, when the inflow and outflow of energy and substances are balanced. For example, in a certain body of water, the growth of algae is limited under natural conditions by a lack of phosphates. Nitrogen compounds are found in excess in water. If they start dumping into this reservoir wastewater with a high content of mineral phosphorus, then the reservoir may “bloom”. This process will progress until one of the elements is used up to the restrictive minimum. Now it may be nitrogen if phosphorus continues to be supplied. At the transition moment (when there is still enough nitrogen and enough phosphorus), the minimum effect is not observed, i.e., none of these elements affects the growth of algae.

The second takes into account the interaction of factors and the adaptability of organisms. Sometimes the body is able to replace the deficient element with another, chemically similar one. Thus, in places where there is a lot of strontium, in mollusk shells it can replace calcium when there is a deficiency of the latter. Or, for example, the need for zinc in some plants is reduced if they grow in the shade. Therefore, a low zinc concentration will limit plant growth less in the shade than in bright light. In these cases, the limiting effect of even an insufficient amount of one or another element may not manifest itself.

Law of Tolerance

The concept that, along with a minimum, a maximum can also be a limiting factor was introduced 70 years later in 1913 after Liebig by the American zoologist W. Shelford. He drew attention to the fact that not only those environmental factors whose values ​​are minimal, but also those that are characterized by an ecological maximum can limit the development of living organisms, and formulated the law of tolerance: “ The limiting factor for the prosperity of a population (organism) can be either a minimum or a maximum of environmental impact, and the range between them determines the amount of endurance (tolerance limit) or the ecological valency of the organism to this factor)" (Fig. 2).

Figure 2 - Dependence of the result of an environmental factor on its intensity

The favorable range of action of an environmental factor is called optimum zone (normal life activities). The more significant the deviation of a factor’s action from the optimum, the more this factor inhibits the vital activity of the population. This range is called zone of oppression or pessimism . The maximum and minimum transferable values ​​of a factor are critical points beyond which the existence of an organism or population is no longer possible. The tolerance limit describes the amplitude of factor fluctuations, which ensures the most fulfilling existence of the population. Individuals may have slightly different tolerance ranges.

Later, tolerance limits for various environmental factors were established for many plants and animals. The laws of J. Liebig and W. Shelford helped to understand many phenomena and the distribution of organisms in nature. Organisms cannot be distributed everywhere because populations have a certain tolerance limit in relation to fluctuations in environmental environmental factors.

Many organisms are capable of changing tolerance to individual factors if conditions change gradually. You can, for example, get used to the high temperature of the water in the bath if you get into warm water, and then gradually add hot. This adaptation to a slow change in factor is a useful protective property. But it can also be dangerous. Unexpectedly, without warning signs, even a small change can be critical. A threshold effect occurs: the last straw could be fatal. For example, a thin twig can cause a camel's already overloaded back to break.

The principle of limiting factors is valid for all types of living organisms - plants, animals, microorganisms and applies to both abiotic and biotic factors. For example, competition from another species may become a limiting factor for the development of organisms of a given species. In agriculture, pests and weeds often become the limiting factor, and for some plants the limiting factor in development is the lack (or absence) of representatives of another species. In accordance with the law of tolerance, any excess of matter or energy turns out to be a pollutant. Thus, excess water, even in arid areas, is harmful, and water can be considered a common pollutant, although it is essential in optimal quantities. In particular, excess water prevents normal soil formation in the chernozem zone.

The following was found:

· organisms with a wide range of tolerance to all factors are widespread in nature and are often cosmopolitan, for example, many pathogenic bacteria;

· Organisms may have a wide range of tolerance for one factor and a narrow range for another. For example, people are more tolerant to the absence of food than to the lack of water, i.e., the tolerance limit for water is narrower than for food;

· if conditions for one of the environmental factors become suboptimal, then the tolerance limit for other factors may also change. For example, when there is a lack of nitrogen in the soil, cereals require much more water;

· the limits of tolerance in breeding individuals and offspring are less than in adult individuals, i.e. females during the breeding season and their offspring are less hardy than adult organisms. Thus, the geographic distribution of game birds is more often determined by the influence of climate on eggs and chicks, rather than on adult birds. Caring for offspring and careful attitude towards motherhood are dictated by the laws of nature. Unfortunately, sometimes social “achievements” contradict these laws;

· extreme (stressful) values ​​of one of the factors lead to a decrease in the tolerance limit for other factors. If heated water is released into a river, fish and other organisms spend almost all their energy coping with stress. They lack energy to obtain food, protect themselves from predators, and reproduce, which leads to gradual extinction. Psychological stress can also cause many somatic (gr. soma- body) diseases not only in humans, but also in some animals (for example, dogs). With stressful values ​​of the factor, adaptation to it becomes more and more “expensive”.

It is possible to identify probable weak links in the environment that may turn out to be critical or limiting. With targeted influence on limiting conditions, it is possible to quickly and effectively increase plant yields and animal productivity. Thus, when growing wheat on acidic soils, no agronomic measures will be effective unless liming is used, which will reduce the limiting effect of acids. Or, if you grow corn in soils with very low phosphorus content, then even with enough water, nitrogen, potassium and other nutrients she stops growing. Phosphorus in this case is the limiting factor. And only phosphorus fertilizers can save the harvest. Plants can also die from too much water or excess fertilizer, which in this case are also limiting factors.

If a change in the value of the limiting factor leads to a much larger (in compared units) change in the output characteristics of the system or other elements, then the limiting factor is called control element in relation to these latter controlled characteristics, or elements.

Often in a good way identifying limiting factors is the study of the distribution and behavior of organisms on the periphery of their range. If we agree with the statement of Andrevarta and Birch (1954) that distribution and abundance are controlled by the same factors, then studying the periphery of the range should be doubly useful. However, many ecologists believe that the abundance in the center of the range and the distribution on its periphery can be controlled by completely different factors, especially since, as geneticists have discovered, individuals in peripheral populations may differ from individuals in central populations at the genotype level.

Conclusion

In this work, I examined in detail the definition, types, laws and examples of limiting factors.

After analyzing the work, I drew conclusions.

Identification of limiting factors is an approximation technique that reveals the roughest, most significant features of the system.

Identification of limiting links allows one to significantly simplify the description, and in some cases, to qualitatively judge the dynamic states of the system.

Knowledge of limiting factors provides the key to ecosystem management, so only skillful regulation of living conditions can give effective management results.

The concept of limiting factors, originating from the classical works of Liebig, is actively used in biochemistry, physiology, agronomy, as well as in quantitative genetics.

A key role in evolution is played by limiting factors of organization that limit the possibilities of certain directions of evolution.

The value of the concept of limiting factors is that it provides a starting point for exploring complex situations.

Identifying limiting factors is the key to controlling the life activity of organisms.

Identifying limiting factors is very important for many activities, especially Agriculture.

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