Attempt to accurate the palaeophytosociological method in peat deposit investigations

Productivity of fruits and seeds of some more important plant associations of lowland mires in the valley of Biebrza river has been investigated. The results obtained were compared with results of stratigraphic analyses. These investigations aimed into accuration of the palaeophytosociological method of reconstruction of the subfossil plant association. The productivity of fruits and seeds of some species is in accordance with quantities occurring in peat-samples. Some other species do not exhibit such an accordance. Reasons are diversified. Of great importance is that the modern quantitetive data explain reasons why seeds of given species dominate in peat-samples and clearly show that the subfossil plant communities can be reconstructed, especially if accompanying species represented by seeds and vegetative remnants are also considered. Data on productivity of seeds and fruits of all peat-forming with regard to the particular plant association should be elaborated. This would make interpretation of results of stratigraphic analyses easier and the reconstruction of subfossil plant associations more reliable.