Absolute jährliche Pollenniederschlagsmengen an verschiedenen Beobachtungsorten in der Bundesrepublik Deutschland

Abstract

Pollen deposition at nine localities was investigated from 1969 to 1971. The annual pollen catches, made in Tauber pollen collectors (and, too, in some Bergerhoff dust collectors), were analysed with respect to their composition by absolute countings using the method of Jørgensen 1967. The data obtained were compared in different respects, the more general results being as follows: 1. Collectors of the same type, exposed at one locality at distances of only a few meters from each other yielded very different pollen quantities and still more different numbers of the single pollen types. The reason for these “accidental” differences must be a very uneven distribution of the pollen in the air, caused by very different pollen concentrations in the single turbulence elements. 2. The comparision of collectors of different types (Tauber and Bergerhoff vessels) yielded no constant relation between each other; if such a relation existed generally, it would always be concealed by the much greater differences just mentioned between one collector and the other. 3. Much greater than the differences of short time and very local character are those from year to year at one sampling site, caused by different flowering intensity, different frost damages and different meteorological conditions of pollen transport. 4. For some plant species the years of maximum pollen deposition were the same over the whole area under investigation, for other species the maximum pollen years coincided only over a more limited area. 5. The average annual pollen deposition rate, covering all anemophilous pollen types, was very similar for most of the sampling sites (2200 to 3600 pollen grains/cm 2 ). Much lower values were obtained only for an island site (Sylt), higher values, up to more than 11.000 pollen graim/cm 2 , were correlated with urban sampling sites. 6. It was shown that pollen deposition contributes only to low extent (ca. 1–2 %, in all cases less than 5 %) to the whole dust deposition. Some further results concerning the correlations between the actual vegetation of the sampling sites and their average pollen spectra, the amount of local pollen deposition, the differences in pollen deposition between landscapcs poorer and richer in forests etc. will be reported in the following text and tables.