Oldal 152 [152]
OCR
150 IVII. Zoocoenological characteristics populations are visibly active, while the other populations of the catenarium are endophytobionts, or even endozoobionts, and for their census, the methods used so far, are insufficient. It is striking, although an entirely logical phenomenon, that the abundance of the semaphoront groups Episyrphus and N. maculaalba greatly increases. This is natural, because each female lays many eggs, thus the number of larvae are, necessarily, higher than those of adults, which is a characteristic of every intra-cyclical dynamic. The initial abundance of adults is always lower than that of their larval progeny, but the latter will also gradually decrease (see “Artgleichgewicht’, Schwenke, 1953). Could we gain such an insight, even into the quantitative structure of this catenarium, not to mention other features, had we only censused the adult semaphoronts? This is obviously impossible, as a collection using sweep nets, or sampling quadrats, would have lead, unavoidably, to the result that the poppy seed-head weevil disappeared without a trace after flowering, leaving only the aphids with a noticeable population. From this, it also follows that a full census of a zoocoenosis is only possible by applying a multitude of census methods, even if their comparison, due to the methodological differences, can only be imperfect. In our case, it became clear that the seed weevil’s disappearance was not real, and its larval semaphoront is really active at a higher abundance; we also detected semaphoront groups that we had not registered during the previous aspectus - even though they were present, but below the detection threshold. The obstant elements connected to the larvae of N. maculaalba are, obviously, already active in the aspectus, as well as the endozoobionts of the A. fabae population. We only censused them during the subsequent aspectus, but also indicated their presence here. The parenthesis indicates that these are not data obtained by direct studies, but retrospectively from the values found during the A. fabae aspectus. We have to assume that they were also active during the preceding period, and it is likely that their number washigher, as these obstants are not exempt from various mortality factors. Accordingly, the dominance values of the larval aspectus of the N. maculaalba increased. While the dominance value of the first aspectus was 2.17, this jumped to 51.52 during the second aspectus, indicating that this is the most dynamic stage in the life of the catenarium. Had we not considered the endophytobiont populations, most species would have to be deleted from the list, which is not permitted from an ecofaunistic point of view and, in zoocoenology, it does not make sense. Merely, a semaphoront has disappeared, but not the species itself that continues to be present, only represented by a different semaphoront. The obstants whose data are in parentheses, were already there, thus we cannot omit them. The futility of a viewpoint from production biology is exemplified in Woynarovich’s (1954) opinion, who states that the ecto- and endoparasites are on the same level as their host. From the perspective of energetics, this cannot be faulted, yet it is unacceptable to a zoocoenologist, because what occurred here is very important form a
