Seite 32 [32]
30 | IL. Biocoenosis and zoocoenosis
advanced biocoenoses can speed this process up (e.g. the arrival of pioneer
plants).
The formation of the biocoenosis is, therefore, also influenced by the
environment, but the impact of the space that it occupies is also decisive.
From the first minute, there is a tight interaction between the biocoenosis
and its non-living environment, which only becomes more and more complex;
Schwenke (1953) was right to notice that the biocoenosis is a manifestation
of the abiotic-biotic factor complex that is inseparable from the biocoen, and
which is characterised by the organisms present.
The complex relationships present in a biocoenosis pose a formidable
problem for the researcher. The fact that the biocoenosis can be divided into
structural elements, allows that we start the exploration of the biocoenosis
with the analysis of one of these groups, especially the links that binds this
group to the others. However, precious little attention has been afforded in
this direction, because the living world appears to us in the form of two major
groups, one being the macroflora, and the other the macrofauna. Naturally,
biocoenological research started (and continues, practically, even today) on
these easily defined groups.
It follows from the unity of the biocoenosis, that both the animal and plant
associations are entirely embedded in it, cannot be separated from it, nor be
removed, but occur as a regularly repeating, identifiable phenomenon that
can be observed and analysed. During such study, one should not forget that
the biocoenosis contains unbreakable bonds throughout the plant and animal
associations; for example, the obstant elements within a zoocoenosis are
represented not only by animals, but obstants of plant origin also find their
way into animal bodies and that, without sustinents of plant origin (symbionts,
the bacterial flora of digestive tracts, etc.), animal life is hardly imaginable.
The tight integration of structural components is obvious, and manifests
itself in the mixed plant and animal membership in the groups of corrumpents,
obstants and sustinents.
Just as one can distinguish plant and animal associations that differ in
structure, as well as in evolutionary origin, there also exist biocoenoses that
are not merely the sum of those two, but include additional, microbiotic
elements and, with them, form more complex associational units of higher
order. This tiny world, whose membership includes producents, but is mostly
composed of reducents, obstants and sustinents, has vital links to both the
animals and the world of higher plants; they form as indispensable an element
of communal life as do the producents represented by higher plants (see
Sukatchev, 1950).
The biocoenosis is bound together effectively by these components, more
so as life on earthalso started with such tiny organisms (Sod, 1953), and the
rich tapestry of life, with its expanded morphological richness of higher
plants and animals, has developed from them. It would be much more logical
to define the units of association starting from these microorganisms, and