They enter into a competitive relationship for food. Competition is an example of competitive relationships in nature. Struggle for existence

Competitive relations.

If in an ecological system two or more species (populations) with similar ecological requirements live together, a negative type of relationship arises between them, which is called competition (? ?). In the general sense of the word “competition” means confrontation, rivalry, competition. In fact, when two populations use the same environmental resources, competition inevitably arises between species for the mastery of these resources. Moreover, each population experiences oppression from the other, which negatively affects their growth and survival and can even lead to the displacement and disappearance of one of them, which is less adapted.

Competition is extremely widespread in nature. For example, all plants compete (compete) for light, moisture, soil nutrients and to expand their habitat. Animals fight for food resources and for shelters (if they are in short supply), that is, ultimately, also for territory. However, if the population is not large and consists of a few, rarely occurring species, the ecological significance of competition will be negligible: for example, in arctic or desert areas there is almost no plant competition for light.

Competition cannot be considered simply by organisms using the same thing. natural resource. Negative interaction can only be discussed when this resource is scarce and when joint consumption has an adverse effect on the population.

Types of competitive relationships

Competitive interaction may concern territory, food, light, shelter and all other types of environmental resources. The outcome of the competition represents huge interest not only for ecologists studying the processes of formation of the composition of natural communities, but also for evolutionists studying the mechanisms of natural selection.

Competition is divided into intraspecific and interspecific. Both intraspecific and interspecific competition can play a large role in the formation of species diversity and population dynamics of organisms.

Intraspecific competition. Territoriality

Intraspecific competition? it is a struggle for the same resources that occurs between individuals of the same species. This is an important factor in the self-regulation of population numbers.

Do some organisms, under the influence of intraspecific competition for living space, develop an interesting type of behavior? territoriality. It is characteristic of many birds, some fish, and other animals.

In birds, territoriality manifests itself as follows. At the beginning of the breeding season, the male identifies “his” territory (habitat) and defends it from invasion by males of the same species. Let us note that the loud voices of males, which we hear in the spring, only signal “ownership” of the site they like, and do not at all set themselves the task of entertaining the female, as is usually believed.

A male who strictly guards his territory has a greater chance of successfully mating and building a nest, while a male who is unable to secure a territory for himself will not participate in reproduction. Sometimes the female also takes part in protecting the territory. In a protected area, the difficult care of the nest and young will not be disturbed by the presence of other parental pairs.

Defense of territory is not necessarily accompanied by active struggle. Loud singing and threatening poses are usually enough to drive away a competitor. However, if one of the parent partners dies, it is quickly replaced by a bird from among the individuals that have not yet settled. Thus, territorial behavior can be considered a regulator that prevents both overpopulation and underpopulation.

A striking example of intraspecific competition that everyone could see in the forest? so-called self-thinning in plants. This process begins with the seizure of territory: for example, somewhere in an open place, not far from a large spruce tree that produces many seeds, several dozen seedlings appear? small Christmas trees. Is the first task completed? the population has grown and taken over the territory it needs to survive. Thus, territoriality in plants occurs differently than in animals: a site is occupied not by an individual, but by a group of them (part of the population).

Young trees grow, simultaneously shading and suppressing herbaceous plants located under their crowns (this is an example of interspecific competition (see here)). Over time, an inevitable difference in growth appears between the trees: some, which are weaker, lag behind, others? are overtaking. Because spruce? a very light-loving plant (its crown absorbs almost all the incident light), weaker young fir trees begin to increasingly experience shading from tall trees and gradually dry out and die.

In the end, after many years in a clearing, out of hundreds of fir trees, only two or three trees remain (the strongest individuals of the entire generation). But there are no longer any grasses, the roots of the trees are spread throughout the clearing, and nothing prevents the lush coniferous crown from being pulled even higher towards the sun.

In some species, intraspecific regulation begins long before serious competition is detected. Thus, a high density of animals is a depressive factor that reduces the rate of reproduction of this population even with an abundance of food resources. (See Part II. Population ecology? deecology.)

Intraspecific competition is an important regulator controlling population growth. Thanks to this competition, a certain relationship arises between population density and the rate of death (mortality) or reproduction (fertility) of individuals. This, in turn, leads to the emergence of a certain connection between the number of parental pairs and the number of offspring they produce. Such connections act as regulators of population fluctuations...

1) Why do competitive relationships arise in nature?

Between organisms different types, making up this or that biocenosis, mutually harmful, mutually beneficial, beneficial for one side and unprofitable or indifferent for the other side and other relationships develop.

One of the forms of mutually harmful biotic relationships between organisms is competition. It occurs between individuals of the same or different species due to limited environmental resources. Scientists distinguish between interspecific and intraspecific competition.

Interspecific competition occurs when different species of organisms live in the same territory and have similar needs for environmental resources. This leads to the gradual displacement of one type of organism by another that has advantages in the use of resources. For example, two species of cockroaches - red and black - compete with each other for habitat - human habitation. This leads to the gradual displacement of the black cockroach by the red one, since the latter has a shorter life cycle, it reproduces faster and uses resources better.

Intraspecific competition is more acute than interspecific competition, since individuals of the same species always have the same resource needs. As a result of such competition, individuals weaken each other, which leads to the death of the less adapted, that is, to natural selection. Intraspecific competition that arises between individuals of the same species for the same environmental resources negatively affects them. For example, birch trees in the same forest compete with each other for light, moisture and soil minerals, which leads to their mutual oppression and self-thinning.

Interactions between different species can take many different forms. Predators hunt their prey, people domesticate animals, populations fight over territory, and much more. For the most part, encounters between different species can be characterized as antagonistic or indifferent. But there are also mutually beneficial partnerships. Some variations of this “cooperation” can be quite unexpected.

10. Crows help wolves hunt

In the past, gray wolves were considered extremely dangerous and, for example, in America they were almost completely destroyed in the 1970s. Since then the populations have recovered. Their reintroduction into Yellowstone Park has had a beneficial effect on the local ecosystem, especially in areas occupied by forest health officials.

Many herbivores die of starvation at the end of winter. At the same time, most of their meat disappears, because predators simply do not have time to eat it before it completely decomposes. With the advent of wolves, herbivores do not die in large numbers at once, but more evenly throughout the year. Moreover, unlike other animals, such as bears, wolves, after they are full, move away from their prey. And the crows enjoy the leftovers from the master’s table. They have learned to take full advantage of the benefits of their proximity to gray predators. With the onset of winter, they sit not far from the future victim and begin to croak loudly, calling wolves and showing them the location of the prey. Perhaps this is why predators are quite loyal to birds feeding near them.

9. Gravedigger beetles and their favorite mites

In nature, the carcass of an animal is a gift that rarely goes unclaimed. Gravediggers, as the name suggests, feed on carrion. Even their body is optimally shaped for moving underground and inside a corpse. The smell of a recently dead and decaying animal soon attracts beetles, sometimes carrying mites on their backs.

The beetles lay their eggs in rotting meat, which will serve as food for their larvae. However, they are far from the only species that do this, so it is quite natural that these larvae will compete with the offspring of other species. Unlike other species, such as various flies, gravediggers need to lay eggs in the corpses of animals, and not in any other place, because only by eating meat can the larvae survive. Adults eat the offspring of competing species, but due to their huge number, they simply cannot cope with them all.

And then their passengers come to their aid. Upon arrival at a fresh corpse, the mites descend from the beetles and consume all eggs and larvae that do not belong to the gravediggers, thereby significantly reducing competition. And then the gravediggers move the ticks to the next corpse. It's possible that the mites also clean bacteria from the beetles' bodies, in exchange for a free ride, so to speak.

8. Daniel Greene and the Seizure Warning Snake

You've probably heard of dogs warning you of an upcoming seizure. What about the snake? Daniel Green Shelton from Washington is the owner of just such a specimen. He uses Bedrock, a 1.5-meter boa constrictor, for exactly this purpose. Green, who suffers from grand mal seizures, often wears Bedrock around his neck. He noticed that as the attack approached, the boa constrictor squeezed his throat a little.

Bedrock always warns of an attack quite accurately and in time, so Daniel has time to calm down, take medicine and take measures to prevent or survive the attack as safely as possible. But the problem is that at night, when Bedrock is sleeping, it is very easy to miss the approaching blow.

Greene's method of preventing seizures, unfortunately, often causes difficulties. For example, some store managers are not at all happy with a customer with a snake around his neck. As a service animal, Bedrock is legally free to accompany its owner in public places. Green says he doesn't mind leaving the store if asked politely. But he gets offended when managers try to argue that Bedrock is not a real service animal.

7. Badgers and coyotes team up

Badgers and coyotes share the same food preferences in the form of a variety of rodents. But they hunt differently. Squirrels and prairie dogs have no chance of escaping from a coyote unless they hide in their burrows. A badger, on the other hand, can dig and drag the rodent out of its home unless it digs another way out. A team of badger and coyote may be able to tip the scales in their favor and successfully capture the animal, if only the competing species can work together.

As it turns out, that's exactly what they do. The Indians have been talking about such cooperation for years, and in Lately scientists have attested to this. When coyotes and badgers work together to catch prey, they complement each other. The badger hunts underground while the coyote chases down its prey. Such friendships most likely take place between single individuals rather than packs.

6. Frogs protect spider eggs for shelter.

The huge Colombian tarantula can easily eat a small animal, such as a frog the size of a hummingbird. But he doesn't do this. It's unlikely that small frogs taste bad to a spider. But there are things more important than food. The spider and the frog were found in the hole made by the former. There is evidence that some Colombian spiders cohabit even more closely with one amphibian.

Often these frogs have to crawl under or slide over the tarantula to get into the hole without being attacked. Spiders take them, study them, and then release them. Most likely, they recognize frogs by some kind of chemical signature.
The two species entered into a mutually beneficial agreement. Many predators who are not averse to feasting on tiny amphibians do not dare to enter the habitat of a huge hunting tarantula. And frogs have the opportunity to feast on small invertebrates left over from the feast of the owner of the house. In addition, a favorable microenvironment has been created for the frog in the spider nest. How do these animals pay the rent? They eat ants, including those that could destroy the spider's eggs.

5. The all-seeing eye of bulls

The pistol shrimp is so named for its ability to retract its claw at lightning speed, creating high water pressure that can repel a predator or stun its prey. This arthropod always needs to be on guard, because it can only be safe in its own burrow. The matter is further complicated by the fact that the shrimp has very poor eyesight.

Some types of gobies come to their aid. They, with their much sharper vision, replace the eyes of the pistol shrimp. In many ways, they perform the same function for shrimp as a guide dog does for humans. Its caudal fin is in constant contact with the antennae of the crustacean. If a predator appears, the fish will warn its companion about the need to retreat. And the goby spends the night in a shrimp hole. This couple does not leave home without each other.

4. The CIA trains ravens in espionage

Operant learning theory B.F. Skinner's (classic example - a dog will receive food in exchange for some action) has proven to be very useful. On its basis, many interesting objects were formed, such as, for example, a seemingly harmless landmark in Hot Springs (Arkansas), which appeared in 1960.

The so-called IQ Zoo is a theme park where animals live, trained to perform human actions. For example, chickens play baseball, pigs play the piano, and raccoons play basketball.

This fun IQ Zoo was also used as a platform to explore other possibilities of animal training, its application, for example, in espionage. The Ravens appeared to be the most promising in this regard. In addition to being able to deliver surprisingly heavy loads, they could perform very specific tasks, such as opening folders with documents.

It was quite simple to train the ravens to fly to the desired location, indicated by a laser, and carry various loads, including video surveillance devices. They even knew how to take pictures using a camera located in their beak. The birds went to the indicated window and pressed a button. Each press took a photo.

3. Rock perches and moray eels

Perhaps the collaboration between coyotes and badgers, who lead essentially similar lifestyles, is not so surprising. What about two significantly less sociable fish? Groupers and moray eels are like night and day. Sea bass hunt during the day in the open. Of course, the pursued prey can escape from the predator by hiding in a crevice. Moray eels, on the other hand, are nocturnal, sneaking through narrow passages in coral reefs to grab their dinner.

In the Red Sea, some groupers have learned to ask moray eels for help. If the intended victim sea ​​bass hides from him in a crevice, he will go straight to the moray eel’s lair. The grouper begins to quickly shake its head towards the entrance of the shelter, calling the moray eel, despite the daytime. Well, the one, led by the perch, heads to where the victim is hiding. She then slips inside and kills her prey. Sometimes she eats it herself, and in other cases she gives what she catches to the perch. This type of cooperation has never been seen before between the two various types fish Biologists have noted that the behavior of fish is variable, which does not suggest that only instinct takes place in their relationships.

2. Meat ants and caterpillars

Meat ants, also known as gravel ants, live exclusively in Australia. They furiously patrol the clearly defined boundaries of their territories, which practically do not overlap with the territories of other colonies. If this suddenly happened, then two colonies of meat ants meet, stand on their front paws and hit their opponents in the stomach with their hind paws. This ritual can last for several days, despite the fact that some of the insects die.

They are so irreconcilable not only towards other ant colonies, but also towards other invertebrates. If someone encroaches on inhabited territories, the ants gather together, kill and eat the uninvited guests. A large number of these workers can drive away even a very large animal, despite the absence of stingers. They release foul-smelling substances and bite repeatedly. The areas around the colonies (which are approximately 650 meters) are often cleared of all extraneous species that cannot coexist with meat ants.

However, some types of caterpillars can not only coexist peacefully with ants, but also extremely welcome such a neighborhood. The caterpillars secrete a sweet liquid that the ants happily consume. And in exchange, they protect the caterpillars from predators.
By the way, farmers can also benefit from the proximity of meat ants. Dead livestock is placed on an anthill, and in the near future the bones are cleared of meat - a convenient way of disposal.

1. Old Tom Killer Whale Helps Whalers

Twofold Bay, near Eden (in Australia), is the third deepest natural harbor in the Southern Hemisphere and a famous gathering point for whales - an ideal hunting ground for these mammals. In the 1860s, the Davidson family operated a whaling station on these shores.

Every year, as winter approached, a small pod of killer whales appeared in the bay. Initially, the Davidsons were afraid that they would hunt whales themselves, but things turned out differently. The pod, led by a male later named Old Tom, trapped the whales in the bay. Then Old Tom swam to the whaling station, beat his tail and attracted the attention of the whalers.

People on their boats went to catch the giant. Some say killer whales have even protected people from sharks. When a whale was caught and killed, its carcass was left tethered in the water overnight. Old Tom and his crew ate the lips and tongue, leaving the more valuable meat for the Davidsons. This union came to be called the “Law of Language.”
The Platypus: Nature's Swiss Army Knife

Antibiosis is a form of relationship in which both interacting species or one of them experiences a harmful, life-suppressing influence from the other.

Neutrality is a form of relationship in which there are no direct interactions between species and they do not significantly influence each other.

In nature, such relationships between organisms are quite difficult to detect, since the complexity of biocenotic connections leads to the fact that most species at least indirectly influence each other.

For example, many forest animals (shrews, small rodents, squirrels, woodpeckers) are not directly related within the biocenosis, but all depend on the supply of coniferous seeds and on this basis they indirectly influence each other.

Relations of neutralism are characteristic of species-rich communities.

Competition (- -).

Competition(from Latin concurro - collide, knock) - This is a form of relationship that is observed between organisms when they share environmental resources, the quantity of which is not enough for all consumers.

Competitive relationships play an extremely important role in the formation of species composition, the distribution of species in space and the regulation of the number of species in a community.

Distinguish intraspecific and interspecific competition.

Intraspecific competition - This is a struggle for the same environmental resources that occurs between individuals of the same species.

Intraspecific competition is the most important form of struggle for existence, which significantly increases the intensity of natural selection.

In this case, interspecific competition manifests itself more sharply, the more similar the ecological needs of competitors are.

There are two forms of interspecific competitive relations: direct and indirect competition.

Direct (active) competition - suppression of one species by another.

With direct competition between species, directed antagonistic relationships develop, which are expressed in different forms mutual oppression (fights, blocking access to a resource, chemical suppression of a competitor, etc.).

Moreover, in many birds and animals aggression is the main form of relationship that determines the competitive displacement of one species by another in the process of struggle for common resources.

For example:

- in forest biocenoses, competition between wood mice and bank voles leads to regular changes in the habitats of these species. In years with increased numbers, wood mice inhabit a variety of biotopes, displacing bank voles to less favorable places. And, conversely, voles, with their numerical superiority, widely settle in places from which they were previously driven out by mice. It was shown that the mechanism of competitive habitat division is based on aggressive interactions;

- sea urchins that have settled in coastal algae physically eliminate other consumers of this food from their pastures. Experiments with removal sea ​​urchins showed that algae thickets are immediately colonized by other animal species;

- in European human settlements, the gray rat, being larger and more aggressive, completely replaced another species - the black rat, which now lives in steppe and desert areas.

Indirect (passive) competition - consumption of environmental resources needed by both species.

Indirect competition is expressed in the fact that one of the species worsens the conditions of existence of another species that has similar environmental requirements, without having a direct impact on the competitor.

With indirect competition, success in competition is determined by the biological characteristics of the species: intensity of reproduction, growth rate, population density, intensity of resource use, etc.

For example:

- broad-toed and narrow-toed crayfish cannot co-exist in the same reservoir. Usually the winner is the narrow-fingered crayfish, as the most prolific and adapted to modern conditions life;

- in human settlements, the small red Prussian cockroach replaced the larger black cockroach only because it is more fertile and better adapted to the specific conditions of human housing.

A classic example of indirect interspecific competition are laboratory experiments conducted by the Russian scientist G.F. Gause, based on the joint maintenance of two types of ciliates with a similar feeding pattern.

It turned out that when two types of ciliates were grown together, after some time only one of them remained in the nutrient medium. At the same time, ciliates of one species did not attack individuals of another species and did not release harmful substances to suppress a competitor. This was explained by the fact that these species were distinguished by unequal growth rates and the faster growing and reproducing species won in the competition for food.

Model experiments conducted by G.F. Gause, led him to formulate the widely known principle of competitive exclusion (Gause’s theorem):

Two ecologically identical species cannot exist together in the same territory, i.e. cannot occupy exactly the same ecological niche. Such species must necessarily be separated in space or time.

From this principle it follows, that coexistence of closely related species in the same territory is possible in cases where they differ in their ecological requirements, i.e. occupy different ecological niches.

For example:

- insectivorous birds avoid competition with each other by searching for food in different places: on tree trunks, in bushes, on stumps, on large or small branches, etc.;

- hawks and owls, which feed on approximately the same animals, avoid competition due to the fact that they hunt at different times of the day: hawks hunt during the day, and owls hunt at night.

Thus, interspecific competition that occurs between closely related species can have two consequences:

- displacement of one species by another;

- different ecological specialization of species, allowing them to exist together.

One of the leading processes shaping the species and spatial structure of a plant community is competition. In essence, this is competition that arises between populations or individual plants when they interfere with each other: there is not enough light, moisture, nutrients, etc. for everyone. Moreover, the mutual influence of woody plants can be very different.

Competition

Competition occurs when interactions between two or more plants or populations with similar ecological needs adversely affect the growth, development, and survival of each. Basically, this happens when there is a lack of any vital resource necessary for everyone - light, moisture, nutritional components.

Competition may be symmetrical (competing plants mutually limit resource consumption approximately equally) or asymmetrical (different mutual restrictions on resource consumption, i.e. one type has a greater influence on the other).

The dominant and the oppressed

The result of competitive relationships is clearly visible in the appearance of woody plants. In any forest (mixed, single- or different-aged), differentiation of trees in growth and development is observed.

• The strongest, largest specimens and with a powerful developed crown - dominant. There are few of them, but they are distinguished by the most intensive consumption of shared resources.
• The bulk of the forest consists of less strong, but normally developed trees of average size and relatively equal needs - indeterminate.
• Along with this, there are also clearly weak specimens that are lagging behind in development - oppressed.

During long-term competitive relationships, oppressed organisms die, and indeterminate ones become either dominant or oppressed. In forestry this phenomenon is called self-destruction. Similar interactions can be observed in an old even-aged spruce forest. All types of differentiation are clearly visible here - from strong developed trees to weak, dying ones, which find themselves in conditions of strong shading and after some time die from lack of light.

Tree competition using the example of a spruce forest

Suppression of competitors can occur due to the release of toxic compounds by underground and above-ground parts, the mutual interception of mineral nutrients and soil moisture by the root system and sunlight leaf apparatus, due to mechanical interactions.

Brother on brother

Competition is noted as between plants of the same species (intraspecific struggle), and between individuals of different species (interspecific).

• Within the same species, plants are similar and have similar requirements for the environment. In this case, the result of intraspecific competition will depend on the physiological characteristics and individual heredity of each individual organism, as well as on the inequality of individual development conditions, in particular the conditions of the microenvironment that will surround a particular plant (microlows and microhighs of relief, excess or lack of moisture, protection from frost and sunshine, etc.).
• For example, within the same species or breed, the hereditary properties of seeds can vary significantly. Thus, oak seedlings growing from larger mature acorns, all other things being equal, grow more energetically and quickly overtake their weaker competitors. That is, even small initial differences between individuals of the same species will be decisive for their further development.

Ours and others

Competition is much more complex and varied in mixed forest phytocenoses, consisting of several species and species of trees, numerous shrubs, grasses, mosses, and lichens. In this case, the antagonism between plants is often so strong that it leads to the depression of a significant part of the species and their death.

Moreover, the outcome of interspecific competitive relationships is determined not only by the conditions environment, but also by the species characteristics of organisms, their ability to adapt. Even closely related species, with general similarity in requirements for growing conditions, always differ from each other in some way. With more intensive development of one of them, an increasing amount of necessary resources is captured and the less competitive neighbor is gradually displaced.

For example, for mixed even-aged larch-spruce crops, spruce dieback occurs during dry periods. Thanks to a deeper root system, larch could use moisture from deeper soil horizons, which were inaccessible to the spruce root system.

Often the result of competition between different species depends on their numerical ratio. Thus, with the predominance of birches in young pine-birch trees, the pine gradually dies, and the predominance of pines leads to a lag in the growth and development of young birches. In oak forests, with an increase in the proportion of ash admixture (more than 30%), a weakening of the growth of the main species is observed. Ash has a higher transpiration capacity, which leads to more intense soil drying and worsening conditions for joint development.

In forest phytocenoses, competition between entire structural units – different layers of forest vegetation – is clearly visible. The denser the tree canopy, the less developed the underlying subordinate layers and the more depressed the individual plants that form them.

Paradoxical, but what better conditions existence in a phytocenosis, the more intense the struggle for life and the more intense the competition. This pattern is confirmed by data from foresters. In a comfortable environment, arboreal trees grow faster, the processes of crown closure, separation and death of oppressed specimens begin earlier. As a result, there is a higher percentage of dead specimens per unit surface area and fewer mature trees remain, but each individual organism will be better developed and will occupy a larger area.

Unfavorable relationships between plants will affect their appearance and viability (size, leaf color, degree of foliage and decorativeness change sharply), which can lead to the destruction of the planned grouping.

What do they use to hit the enemy?

Competing plants are able to actively influence each other. Suppression of competitors can occur due to the release of toxic compounds by underground and above-ground parts, the mutual interception of mineral nutrients and soil moisture by the root system and sunlight by the leaf apparatus, due to mechanical interactions.

Since lighting plays an important role in the life of plant organisms, competition for light– one of the most acute and pronounced. With different degrees of light transmission, trees that provide stronger shading gradually begin to overtake and suppress competitors. Lack of light can lead to falling branches and leaves, slower growth and development, and ultimately the death of plants. Similar relationships are observed in nature between shade-tolerant and light-loving breeds. Thus, dark coniferous species (spruce, pine, cedar) with dense crowns eventually displace the fast-growing but light-loving birch.

Tree competition: displacement of light-loving trees

Mechanical interactions are characteristic of dense co-growth of trees and manifest themselves in the form of mechanical damage to buds and leaves, as well as in the form of wounds and dry holes formed due to mutual friction of trunks and branches. In species that have flexible branches (birch, aspen, alder), it is common whipping– when swayed by the wind, their branches cause strong blows to the crowns of their neighbors, as a result of which they become noticeably thinner. In this case, young conifers are especially affected; their needles and apical buds are knocked off, growth slows down, and double or triple tips are formed.

An example of a strong root competition can be observed in a swamp pine forest, where the situation is aggravated by the extreme poverty of the soil of the raised swamp in nutritional components. Under such conditions, a sparse tree stand is formed, in which the root systems of neighboring trees overlap many times, forming a dense network.

Tree competition: swamp pine roots

To live in peace and harmony

When creating artificial plantings, the principle of mitigating the severity of competition between plant organisms is used.

The problem of combining incompatible things can be solved by selecting appropriate conditions and careful care.

• When choosing plants for planting, the biological characteristics of growth, development and adaptability of their species, breeds and forms are taken into account.
• You should also pay attention to their height, depth of penetration and shape of the root system, optimal timing of vegetation, flowering and fruiting, and uneven use of habitat resources by plants.

Otherwise, unfavorable relationships between plants will affect their appearance and viability (size, leaf color, degree of foliage and decorativeness change sharply), which can lead to the destruction of the intended grouping.

• In mixed plantings, it is good to combine light-loving and shade-tolerant species, species with shallow and deep root systems, with different periods of intensification of the absorption of nutritional components, demanding and unpretentious species.
• To reduce mutual negative influence between tree species with pronounced competitive relationships, appropriate accompanying neutral species or shrubs can be planted as a kind of buffer.
• When planting, using sufficiently mature seedlings can significantly reduce competition between them at the initial stage of development and avoid significant losses.
• An important role in the formation of tree plantations is played by the choice of optimal planting density and the nature of the placement of trees, taking into account not only their decorative qualities, but also the individual species characteristics of transformation over time.
• It is useful to pay attention to the origin of planting material - seed or vegetative. In the first years of life, trees of vegetative origin (root shoots, coppice) grow faster; during this period they successfully compete with seedlings, which, if not cared for, can fall out of the composition. Subsequently, after reaching the upper tiers, seed trees become biologically more stable.

In general, the topic of plant compatibility with each other and the search for the most harmonious combinations is very extensive, since the nature of the relationships between plant organisms is very complex, can manifest itself in various forms and varies depending on the age of plant organisms, changes in climatic and soil conditions.

It is possible to list only a few well-known specific examples of the unwanted proximity of different breeds and species.

Paradoxically, the better the living conditions in a phytocenosis, the more intense the competition.

Undesirable neighborhood

Do not create mixed plantings birch trees And some conifers. Birch, as a rule, grows faster than conifers and drowns them out. Birch waste products can have a negative impact on the intensity of enzymatic processes in pine and larch. In addition, birch has a powerful root system, consumes a lot of water and deprives all neighboring plants in this regard. Similar effects can also be had maples. It is better to plant shade-loving and unpretentious plants under them.

Ate They are capable of strongly acidifying the soil, so only lovers of acidic soils can get along with them. Among them are ferns, hydrangeas, callas, and begonias.

“Poison” the soil, i.e. cause so-called soil fatigue, decaying leaves chestnutA, nut. This is due to the fact that the leaves of these plants contain phenolic compounds, which begin to be released during the process of decomposition.

An aggressive plant is considered sea ​​​​buckthorn, clogging the space surrounding it with its growth.

Intensively growing poplar is able to quickly overtake and suppress light-loving birches, elms, ash trees, and maples mixed with it, which develop poorly and take on an ugly or curved shape.

Depending on growing conditions, it adversely affects the growth of tree species caragana tree. On dry soils, its root system is located in the upper layers of the soil and, when planted together with oak, pine, and ash, displaces their roots into the lower, less fertile layers.

Under certain conditions oak can drown out ash, maple, white acacia, birch, elm.

Should not be planted among linden and maple trees rhododendrons, since these trees have a shallow root system that quickly intertwines the roots of rhododendrons and intercepts moisture. In addition, their spreading crowns retain precipitation.

Some plants ( beech, sucker, many conifers) have very high allelopathic activity (from the Greek. allelon– “mutually” and pathos- “suffering”), therefore they rarely form single-species plantings. They experience suppression of their own youth due to the accumulation of toxic substances, as a result of which the species displaces itself.

Many herbs (some faster, others slower) as they grow, they choke out neighboring plants, both herbaceous and tree-like, especially creeping varieties of junipers. First of all, this applies to grasses with long rhizomes or forming numerous root suckers, since it is very difficult to combat their expansion.

Suppresses the growth of other plants barberry. This shrub, like white acacia, horse chestnut, fir, viburnum, rose, lilac, rose hip And mock orange, actively suppresses the growth of other plants and belongs to the group of monoplants.

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