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156 | VII. Agrobiocoenoses and their zoocoenoses
in the activity of corrumpents that, in turn, gives rise to plant protection.
Therefore, we see no biological reason that the organisms living in culturally¬
influenced biocoenoses - more specifically, agrobiocoenoses - should not
be considered as essentially similar biocoenoses to those living elsewhere.
There is only one difference: the impossibility of succession, which provides
the conditions necessary for crop plants to flourish.
In attempting to classify cultural biocoenoses, one should recognise that,
because of human activities, the place of ancient, primer biotopes is occupied
by secondary, culturally-influenced biotopes. Their biocoenosis is a cultural
one, in which the producents are mostly cultivated plants, frequently of
species that were introduced from distant lands. The corrumpents and obstants
are, mostly, members of the autochthonous fauna, but also include domesticated
and introduced species. If these biotopes are arranged according to the degree
of human influence, it is obvious that the agrobiotopes are the ones that are
most heavily influenced.
Among agrobiotopes, we count arvideserta, agrilignosa and, also - following
Balogh (1953) - fish ponds, even ifthis may seem strange. Human influence
can cease to operate, temporarily or definitively, in all three, in which case
ruderal biotopes or biocoenoses are formed in the first two, that are not new
formations, but ones that gradually return to the original biocoenosis
determined by the biotope, unless they again become cultivated. According
to Balogh, the essence of ruderal biocoenoses is that their production is not
used, but remains in situ. This, however, does not always happen, so we would
not make this a criterion of the ruderal biocoenosis, because their species
composition can vary. In our definition, ruderal biocoenoses are associations
where human influence has ceased, and succession restarted. Here we are
faced with a conscious, directional human influence.
Hay meadows and grazing lands, as agrobiotopes sensu lato, deserve special
attention because a unique feature is that their soil is not disturbed, unlike
in other agrobiotopes. This difference is very important because, once human
influence stops, instead of forming a ruderal biocoenosis, the community is
enriched by the reappearance of species that are intolerant of regular grazing
or cutting. The stand remains, only it becomes more species-rich. One can
assume that the original ancient conditions will never return, unless the
extinct plant species can recolonise from nearby refugia.
The third group of culturally-influenced biotopes are represented by areas
where human influence is merely the introduction of species foreign to the
biotope (for example, spruce in the Matra Mountains, or Scots pine plantations
of the Buda Hills). These differ from agrobiotopes in that their soil is only
disturbed - slightly - during the planting of the saplings, otherwise remaining
undisturbed for a long period.
A few more words about the agrobiocoenosis sensu stricto. It be incorrect
to consider the areas under dominant crop plants as separate biotopes, given
that the whole arvideserta or agrilignosa is, essentially, under the same