Oldal 31 [31]
§ The concept of biocoenosis | 29
Links among these structural elements elucidate the community relationship
that unites these organisms as a biocoenosis. Irrespective of considering the
traditional triad, or the above-detailed elementary categories, as the essence
of a biocoenosis, it is certain that the concept must refer to an overarching
unit, expressing some sort of totality that is also physically recognisable.
Observing the development of the concept of biocoenosis, we can clearly see
that a large majority of authors aim to express something similarly extensive
and, apparently, want to avoid its use for a small segment of a habitat. By
excluding the “community” interpretation of the biocoenosis, we squarely
fall into this camp ourselves.
Delimiting a biocoenosis is, however, not an easy task, and from the desire
that this concept be restricted to a larger, physiognomically recognisable
unit, it follows that the additional concepts of biological equilibrium and its
consequent homeostasis became included in most definitions. These will be
dealt with in a separate chapter; at this stage, only the following needs to be
acknowledged.
As only the producent organisms can generate organic material, it is without
doubt that the basis of all biocoenoses can only be formed by producents.
The essential point of a biocoenosis is not being, or not being, in equilibrium,
but whether it contains producent organisms; in their absence, a biocoenosis
cannot be formed nor sustained. Additionally, as with life itself, the biocoenosis,
as a form of life, has development potential, starts from a small beginning,
and gradually expands. It follows from the principle of development, that all
biocoenoses start when a producent appears in each space. Therefore, once
a producent is present, we see the start of a biocoenosis that is gradually
enriched by the other structural components, and will reach a climax state
permitted by edaphic and climatic constraints, according to the rules of
succession.
Definitions that emphasise the equilibrium criterion contain the basic
error that they totally ignore the principles of development/evolution, and
that such a definition can only refer to an advanced, complex, climax
association, containing all the component structural elements. An island just
emerged from the sea, or the bare soil of a fresh landslide, is gradually
colonised by organisms. When can we name such an area an “independent”
biocoenosis; when can we apply to them the concept of an equilibrium and
the ability to self-regulate? There are no certain answers to these questions.
A biocoenosis is, therefore, an association of plants and animals that is
gradually formed by various structural elements, but always around producent
organisms, its components are in living interactions with each other, and it is
formed in a definable space of the biosphere, as a physiognomically recognisable
unit.
In theory, all biocoenoses start with the tiniest of producents that make
the soil suitable for a richer community of organisms, but it also follows from
the concept of the biosphere, that the influences from neighbouring, more