OCR
§ Plant and animal associations ] 35 for the resident animals constitutes a space, within which there can be several distinct animal associations. Consider the beech tree, that is but one species in a Fagetum silvaticae association; for animals, it is a higher category, the living space for a rather complex animal association. The lowest category in the taxonomy of plant associations, at least for herbs, is the species but, in the case of animals, there is a further consideration; on a given plant species, there may exist an animal association; the taxonomy of the two does not fully overlap, and plant associations have one category fewer. In this respect, one should recall Dudich’s (1939) arguments, especially that the plant cover has an important role as the generator of the life conditions of a biotope, while this cannot be said of the animals living there. Due to the preceding arguments, the word association will be used exclusively for plant societies while, for animals, the term zoocoenosis will be used. After distinguishing the plant associations from zoocoenoses, let us examine whether there are factors linking zoocoenoses to plant associations? If we find such linkages, we can assume that there is a connection between plant associations and the qualitative composition of zoocoenoses. The plant component of the biocoenosis is, characteristically, rooted to a place, even to a degree that the plant cover can be used to characterise the biotope. The plant cover is present as the same association for long time periods, in the case of woody vegetation for decades; this association-forming plant cover is an essential source of energy for the animals. Hence, the factors sought are present: the relative constancy of the plant association, and its role as energy source. These two necessarily lead to the conclusion that a plant association of a given composition predicts a more-or-less well defined zoocoenosis. Thus, the solution is almost self-evident, that the associational relationships of a zoocoenosis are projected onto the relevant plant association, as its solid foundation. The idea that the zoocoenoses should be linked to plant associations is not new. While Shelford and Tower (1925) suggest that the study of zoocoenoses ought to start from the animal communities themselves, and these are delimited by the area where the dominant species remains dominant, Palmgren (1928, 1930), Krogerus (1932), Rabeler (1937, 1952), Brundin (1934) and Franz (1939) are adamant that the limits of a zoocoenosis, at least in terrestrial habitats, ought to be made considering the plant associations. This is also the standpoint of Hungarian researchers (Balogh and Loksa, 1948; Nagy, 1944, 1947, 1950; Balogh, 1953). All these authors consider the plant associations as the basis for the area occupied by a zoocoenosis, and describe the zoocoenosis by its dominance relations. Theoretically, we are in accordance, but the association-based construction is not elucidated by copying the framework of plant sociology, but in trying to get to the root of the question: what is the causal basis that underlies a given plant association harbours a zoocoenosis of a given species combination?