HET OPPERVLAKTEMONSTER: DE RELATIE TUSSEN STUIFMEELREGEN EN VEGETATIE

Samenvatting

Analysis of modern pollen precipitation is most­ly done from samples collected in moss. Moss polsters are thought to preserve pollen for a fairly long period. Thus accidental peak repre­sentation of certain species is avoided. In the absence of mosses, the upper half and one and a half centimetres of the soil in a dandelion meadow on the Es fields of Yde (province of Drenthe) and a mass polster that developed af­ter 1970 in a newly constructed ditch have been analysed for their pollen content. The pollen spectra represent a vegetation that must have grown there at least one century ago: Plaggen­wirtschaft conditions with buckwheat, cornflower, rye and heather pollen are dominant. A comparable picture is obtained from the twenty­one-year-old pollen precipitation in a farmyard at 1 km from the first samples. The samples in­form us about a past vegetation rather than about the present pollen rain. A reason may be the acid condition of the soils in such farming areas, which was caused either by the applica­tion of heather sods in the manuring system or, in the case of the farmyard, by the presence of a heather podzol, indicating former heath. The transportation of pollen of such past vegetations into modern samples was prabably done by splash water.