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50 | IL. Biocoenosis and zoocoenosis We shall deal with the concept of biotope in the next section. Here, we only note that it is the biotope that is primarily changed due to human activity, and remains in a continuously disturbed state; consequently, the biocoenosis necessarily changes. From statements relating to the structure of the biocoenosis, it follows that human activity will block succession. When interfering with a biotope, an association is destroyed that was in a phase that was moving towards a climax. On the steppe (grassland) of cultural origin thus created, a succession would restart if the agricultural activities did not repeatedly block the process. Human activity, with its cultivation of crop plants, forces foreign producents into the biotope, creating a “plant association”; however, this new association conceals a further association of ruderal and segetal plant species, and these would start the succession, in the absence of more human intervention (Ubrizsy, 1954). In considering the structural elements outlined above, or the older, threelevel classification, there is no doubt that the agrobiocoenoses contain all constituents. The producents are put there by humans, the consuments arrive by themselves (necessitating the birth of plant protection), and reducents must also be present, otherwise soil fertility would drastically be reduced; without all these elements, crop cultivation, that is already demanding, would be impossible. Human influence is immeasurable: the plant cover is transformed, its fauna changed and, in the soil, the fauna and reducent organisms are exposed to incessant disturbance. Nonetheless, the three life elements are present. The fact that in the soil, which, in our opinion, is the most important component in the life of the biocoenosis, only the species spectrum, andabundance relationships change, as confirmed by only a relative change reported in the results of coenological studies in agricultural soils (Franz, 1950; Scharffenberg, 1951; Jahn, 1951). Consequently, we cannot accept why would one consider a biological association living on a site under agricultural cultivation as structurally, i.e. essentially, different from biocoenoses present at relatively less disturbed (because we cannot consider them undisturbed) habitats. This type of human activity is not as unnatural as many believe. It is certain that humans cause changes to the natural world that, at least to a degree, did not exist before the arrival of humans (Tschegolev, 1951); it cannot be doubted that, even under undisturbed natural conditions, there are transformative effects on nature that are the equivalent to human interventions. Essentially, an anthill does not differ from a human settlement: only things that are tolerated by the ant population remain in the vicinity and, within the hill, only what is useful or indifferent for ant activity is accepted. Fungi-farming ants or scolitid beetles are, essentially, “plant growers”, and the dependence of the farmed fungi on these animals is very like the dependence of domesticated plants on humans as a result of plant breeding. The turning over of soil by a family of wild boar is the same as ploughing, and grazing
