Topical connections: definition, features and interesting facts

The scientific theory of biogeocenosis was created by the Russian scientist V. Sukachev. It provides an exhaustive description of natural complexes, as well as various types of interactions between parts of the ecosystem are studied: plants, animals, microorganisms. Particularly serious studies of the forms of biotic relations were conducted by another Russian scientist - V. Beklemishev, who identified four of their types. It should be noted that topical links are one of the most common types of interactions of natural biocomplexes in ecology. They will be studied in this article.

The concept of consortium

Before studying the question of how the topical links are formed in the biocenosis, it is necessary to get acquainted with the biological essence of the concept of consortium. It means long-existing, interrelated relations of several organisms, which depend on individuals of a productive species - the consort. The most common organisms that perform this role are plants or animals. They serve as the nucleus providing individuals of other species, especially food and protection. Living individuals in relation to an inconsorant may be endoconsorts, for example, round or tapeworms-helminths of domestic animals and humans. Ecoconcorts are organisms that live on the surface (individuals that are the core, for example, fish cleaners that live on the shark's body).

If they occasionally come into contact with an inconsorant, they are called exoconsorts (for example, honey bees harvesting nectar from certain plant species).

Trophic and topical links in various consortia

If the nucleus is represented by one organism, then such a community is called individual, and if the whole population or even representatives of the whole biological species, then such a consortium is called population. Trophic and topical connections occur particularly quickly in individuals in a sinus consortium. In this case, one ecobiomorph - a group of autotrophic plant organisms, similar to anatomical and physiological characters and living in similar abiotic conditions - is formed. For example, a group of moderately hygrophilous plants of the gymnosperm section - conifers (fir, spruce, larch) growing on a common area - the area, forms a sinus consortium.

The works of V. Beklemishev

To describe all the complex and diverse interrelationships of organisms that arise within the biogeocoenosis, taking into account the spatial location of individuals relative to each other, the Russian scientist Beklemishev applied the term topical connections. Examples illustrating their education prove that some organisms affect others due to changes in environmental factors. As the scientist himself said, the result of topical relations is the conditioning of the abiotic factors of the external environment, that is, the formation, by one living organism, of certain special physico-chemical conditions for the existence of individuals of a different species. Thus, in the modern science the concept of topical relations was introduced by Beklemishev. So in the freshwater biocenosis - the lake, you can count more than 125 examples of the topical connections of plant and animal organisms.

For example, the dragonfly species Lutka lays eggs in the parenchyma of the leaves of aquatic plants, such as the arrowhead, yellow egg, and the specimen of the Arrow species on the lower part of the leaf blade of the same plants. The hydrobionts living in the freshwater lake mainly use plants as a substrate for the conservation of eggs and feeding of the larvae, and adult specimens of the same species, hydrobionts, inhabit the leaves, stems and roots of aquatic plant producers.

The role of plants in the formation of topical links

Representatives of the flora not only create the basic conditions for the vital activity 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 areas in a special microclimate created by plants-photosynthetic.

It is characterized by a more comfortable temperature regime and optimum humidity. This has a beneficial effect on the livelihoods of mammals, birds and insects - the inhabitants of the tropical jungle and taiga. The topical links, the examples of which we reviewed above, indicate that along with trophic interactions they play a dominant role in natural ecosystems.

Interrelations between organisms in the Arctic biocenosis

Interesting facts about the topical links can be cited by studying the natural complex of the Arctic. In spring, a large number of seabirds fly to the tundra and the islands of the Arctic Ocean: guillemots, eiders, geese. They arrange bird markets. During the laying of eggs (late May - early June) birds occupy steep cliffs, sitting on bare protuberances very close to each other. Neighbors of water birds are typical predators - white owls.

They not only feed young animals or guillemots, but at the same time protect the entire nesting area of waterfowl from the attacks of arctic foxes and other predators. The topical links, the examples of which we considered above, contribute to the survival of individuals of various species living in the extreme climatic conditions of the Arctic zone.

Features of the formation of topical links in the biocenosis of the taiga

By V. Beklemishev's research it was proved that the basis of topical links between organisms is the change in the parameters of existence of individuals of one biological species as a result of the vital activity of organisms of another species. For example, the areas 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 a nutcracker. Individuals of this species are brightly colored with a long and pointed beak of birds. 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 - the Siberian cedar.

Types of relationships between organisms in deciduous forests

The topical connections studied by us, examples of formation of which we have considered in the ecosystems of the Arctic and taiga, will be incomplete, if we do not clarify, the fact that such relationships can have a negative value. So, in the oak forests inhabited by small hymenoptera insects - walnut. With their ovipositor females pierce the peel of oak leaves and inject an egg into their parenchyma. The larva that hatch out of it secrete saliva, under the influence of which a pathological growth of the leaf occurs, called "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 pest larvae.

Topical links between organisms - hydrobionts

A vivid example of the interactions named by the Russian scientist Beklemishev, the topical, can be the vital activity of some species of fish, called "cleaners" on the surface of the body of large aquatic inhabitants - sharks and whales. For example, a species such as the jaws or some species of marine shrimp are the sanitarians of the majority of the inhabitants of warm seas. The skin of sharks and whales is often damaged by parasitic invertebrates, for example, crustaceans, amphipods, isopods. Eating them, cleaners save their "customers" 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 influence its metabolism, as well as vital activity.

Summing up, it can be confidently asserted that the topical connections, examples and formations of which we examined in this article, provide complex and diverse types of interactions, both direct and indirect, between individuals of different species that are part of natural ecosystems-biocenoses.