The scientific theory of biogeocenosis was created by the Russian scientist V. Sukachev. It provides an exhaustive description of natural complexes, and also studies the diverse types of interactions between parts of the ecosystem: plants, animals, microorganisms. Particularly serious studies of the forms of biotic relationships were carried out by another Russian scientist - V. Beklemishev, who identified four of their types. It should be noted that topical connections are one of the most common types of interactions of natural biocomplexes in ecology. They will be studied in this article.
Consortium Concept
Before studying the question of how topical bonds are formed in a biocenosis, it is necessary to get acquainted with the biological essence of the concept of consortium. By it is meant the long-existing, interrelated relationships of several organisms that depend on individuals of a productive species - consort. The most common organisms performing this role are plants or animals. They serve as the core, providing individuals of other species, primarily food and protection. Living individuals in relation to inconsort can be endoconsorts, for example, round or tapeworms - helminths of domestic animals and humans. Ecoconsorts - organisms that live on the surface (individuals that are the core, for example, fish cleaners that live on the body of a shark).
If they occasionally come into contact with inconsort, they are called exoconsorts (for example, honey bees collecting nectar from certain plant species).
Trophic and topical ties in various consortia
If the core is represented by one organism, then such a community is called individual, and if the whole population or even representatives of the entire biological species, then such a consortia is called population. Trophic and topical connections arise especially quickly in individuals in a sinusial consortium. In this case, one ecobiomorph is formed - a group of autotrophic plant organisms that are similar in anatomical and physiological characters and live in similar abiotic conditions. For example, a group of moderately hygrophilous plants of the gymnosperms department - conifers (fir, spruce, larch), growing on a common territory - area, forms a sinusial consortium.
The works of V. Beklemishev
To describe all the complex and diverse relationships of organisms that occur within the biogeocenosis, taking into account the spatial arrangement of individuals in relation to each other, the Russian scientist Beklemishev used the term topical connections. Examples illustrating their formation prove that some organisms act on others due to changes in environmental factors. As the scientist himself said, the result of topical ties is the conditioning of abiotic environmental factors, that is, the formation by one living organism of some special physicochemical conditions for the existence of individuals of another species. Thus, in modern science, the concept of topical connections introduced Beklemishev. So in a freshwater biocenosis - a lake, you can count more than 125 examples of topical relationships of plant and animal organisms.
For example, the Lyutka dragonfly species lays eggs in the parenchyma of leaves of aquatic plants, such as arrowhead leaves, yellow capsule, and individuals of the Strelka species - on the lower part of the leaf blade of the same plants. The hydrobionts that live in the freshwater lake mainly use plants as a substrate for the preservation of eggs and the nutrition of larvae, while adults of the same species - hydrobionts live on the leaves, stems and roots of aquatic plants - producers.
The role of plants in the formation of topical bonds
Representatives of the flora not only create the basic conditions for the life of other organisms, but also themselves actively influence abiotic factors. So, thanks to the vast forests of tropical and Siberian forests, a huge number of organisms live in these territories in a special microclimate created by photosynthetic plants.
It is characterized by a more comfortable temperature and optimal humidity. This favorably affects the life of mammals, birds and insects - the inhabitants of the tropical jungle and taiga. Topical connections, the examples of which we examined above, indicate that they, along with trophic interactions, play a dominant role in natural ecosystems.
Relations between organisms in the Arctic biocenosis
Interesting facts about topical connections can be given by studying the natural complex of the Arctic. In spring, a huge number of seabirds flies into the tundra and the islands of the Arctic Ocean: guillemots, eider, and chistiks. They arrange bird markets. During egg laying (late May - early June), birds occupy steep cliffs, sitting on bare ledges very close to each other. Neighboring waterfowl are typical predators - white owls.
They not only feed on young chistiks or guillemots, but at the same time protect the entire territory of nesting waterfowl from attacks by arctic foxes and other predators. Topical connections, the examples of which we examined above, contribute to the survival of individuals of various species living in extreme climatic conditions of the Arctic zone.
Features of the formation of topical links in the taiga biocenosis
The research of V. Beklemishev proved that the basis of topical connections between organisms is a change in the parameters of the existence of individuals of one biological species as a result of the vital activity of organisms of another species. For example, the ranges of Siberian pine (Siberian cedar) attract many inhabitants of the taiga: squirrels, chipmunks, sables, and, of course, various species of birds. One of them is cedar. The individuals of this species are brightly colored birds with a long and pointed beak. They feed on pine nuts and store them under a layer of taiga moss. Forgetting about these supplies, birds contribute to the spread of the most valuable species - Siberian cedar.
Types of relationships of organisms in deciduous forests
The topical relationships we have studied, the formation examples of which we have examined in the ecosystems of the Arctic and the taiga, will be incomplete if we do not find out the fact that such relationships can also have a negative value. So, small hymenopteran insects - nut growers live in oak forests. Females pierce the skin of oak leaves with their ovipositor and inject an egg into their parenchyma. The larva that hatches from it secretes saliva, under the influence of which there is a pathological proliferation of the leaf, called a “gall”. In it, the larva is well protected from many enemies, but the plant itself reduces photosynthetic activity, since the leaves are affected by the larvae of the pest.
Topical connections arising between organisms - hydrobionts
A vivid example of the interactions, called topical by the Russian scientist Beklemishev, is the vital activity of some fish species, called “cleaners” on the surface of the body of large aquatic inhabitants - sharks and whales. For example, a species such as a guban or some species of sea shrimp are the orderlies of most inhabitants of warm seas. The skin of sharks and whales is often damaged by parasitic invertebrates, for example, amphipod crustaceans, isopods. Eating them, cleaners save their "clients" from infectious diseases caused by pathogenic skin parasites. Thus, one biological species can form not only food interactions with individuals of another species, but also affect its metabolism, as well as vital activity.
Summing up, we can confidently state that the topical relationships, the examples and formation of which we have considered in this article, provide complex and diverse types of interactions - both direct and indirect between individuals of various species that are part of natural ecosystems - biocenoses.