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§ The question of balance in the biocoenosis | 57 ask whether we are misleading ourselves by believing that the number of gradations is higher in agrobiocoenoses than in natural ones? Even if it were so, we cannot conclude that this phenomenon can be explained by a disturbed balance, when it is obvious that fluctuations in population abundance do occur in other biocoenoses. Could this mean that the equilibrium can also be upset in these biocoenoses? If gradations and disequlibrium are equivalent, this suggests no less than that there is only a difference of degree between an agrobiocoenosis and a natural biocoenosis; thus, the criterion of equilibrium cannot be included in the definition of the biocoenosis, as its essence is not the presence or absence of equilibrium, but something else. This “something else” cannot be anything other than the interaction, necessarily present in every association, because this is what creates a coenosis from coexistence. The interaction extends to abiotic factors as well and, the poorer the biocoenosis is in energy sources, and more uniform in ecological life conditions, the more gaps it will contain. For this reason, only populations with special capacities for adaptationcan survive there. The higher the influence of the macroclimate, the less the biocoenosis can dampen these effects, and the more obvious these gaps become. A field of maize has one plant energy base, the macroclimate is unimpeded; there is no canopygenerated shade nor water-storing litter as in the oak forest further away. How could we expect the same conditions and interactions in these two biocoenoses? The result cannot be other than Phyllotreta beetles and beet curculionids will be present on the beet field, and corn borers in the maize as suitably adapted corrumpents, while several obstants that otherwise would feed on them, will not be present due to lack of appropriate adaptations. To explain these differences, why would it be necessary to invoke the fiction of equilibrium (Friederichs, 1930: “Das Gleichgewicht is [...] bemüglich der Lebensgemeinschaft als eines Ganzen nur eine Fiktion, ein gedachter Zustand, von dem die Wirklichkeit immer sehr weit entfernt ist”), when they can be much more simply and incontrovertibly explained by species interactions? The interactions are, without doubt, also present in agrobiocoenoses and explains why crop plant will attract corrumpents, and these their own obstant elements. The soil fauna is in interaction with what happens at above-ground levels, and will become impoverished not only due to less organic debris, but also because it is defenceless against macroclimatic extremes. At the highest level, macroclimate determines the qualitative and quantitative composition of every biocoenosis. On the surface, it supports the fiction of equilibrium but, in reality, destroys it. It is an attractive view that whatever is in a biome, it is in equilibrium with the macroclimate. Essentially, the plants and animals living in a given area are adapted to the conditions provided by the ecosystem, and the macroclimate will be transformed and modified into an ecoclimate, that will affect the association in this form. In addition, the weather extremes of the macroclimate can devastate even living beings that have occupied the space continuously and
