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The results of palynological analyses of the Holocene deposits and modern pollen deposition in Poland and Finland are used to illustrate the progress in pollen analysis - the main palaeoecological method. The increased potential of modern palaeoecology for reconstruction of vegetation and for drawing conclusions on other environmental variables (climate, water conditions, landscape, anthropogenic disturbances) is demonstrated. Pollen analysis - develops at present interpretive tools for precise reconstruction of the structure and composition of vegetation and climate conditions. The progress consists in the quantitative presentation of pollenvegetation-climate relationships based on the examination of modern pollen deposition. The application of numerical analyses to pollen data allows correlating pollen spectrum features with the landscape/vegetation type. Special attention is paid to the Holocene vegetation changes of the transitional zone between boreal forest and tundra in the areas subjected to weak anthropopression (e.g. Lapland), which reflect climatic changes. Databases of modern pollen analogues are based on analysis of samples of surface mosses and contents of Tauber traps. These traps are used in Poland in investigations conducted as a part of the Pollen Monitoring Programme (http://pmp.oulu.fi). The correlation of Tauber-trap data with aerobiological ones contributes to understanding of the relationship between pollen production and climate elements. Additionally, the precise C14 dating allows a near-annual resolution in fossil deposits to be obtained more frequently. Due to time scales comprising hundreds of years, pollen analysis can provide means to resolve questions inaccessible for direct observation.
Pollen deposition of alder has been measured at ground level by means of nine modified Tauber traps in different plant communities according to rules of the Pollen Monitoring Programme (http://pmp.oulu.fi). The series of data covers the period 1998-2006. The area under investigation is situated in the Roztocze (surroundings of the Guciów village) within the protective zone of the Roztocze National Park. During nine years of monitoring, significant variations were observed between single years of deposition. The occurrence of peak years (1998, 2001, 2003 and 2006) connected with higher production of Alnus pollen was observed at many pollen monitoring sites, but its relationship with different proportions of alder within the surrounding vegetation seems rather weak. The average value of annual pollen deposition of Alnus for the whole region was calculated at ca. 1370 grains · cm⁻². At the sites situated within the open landscape, pollen influx values ranged from 442 (in 2005) to 6894 (in 1998). It seems that other factors than the proportion of alder within the vegetation control the deposition of Alnus pollen. Long-distance transport and meteorological factors such as wind speed and direction should be taken into account in future studies.
Anemophilous trees of Betula and Alnus genera produce very high amount of easily spreading pollen. Carpinus and Fagus discharge lower amount of pollen to the atmosphere. Trees belonging to the mentioned genera occur in vegetation cover of Lublin and the Roztocze region where the comparative studies were carried out in the years 1998-2004. The objective of these studies was to determine pollen concentration of four tree taxa in these study areas located 120 km apart. Annual pollen sums, obtained by means of three methods, were compared in order to find similarity of alternating high and low pollen production by trees in particular years. In the Roztocze region the studies were continued during the mentioned seven years as a part of Pollen Monitoring Programme, which provides multi-annual data for the palaeoecological reconstructions of Quaternary and the interpretations of phenologic-climatic nature. Standard Tauber traps were used in the Roztocze area. In Lublin the gravimetric method was used in the years 1999-2000, and the volumetric method — in the years 2001- 2004. Similar trends were found in Lublin and in the Roztocze region as to the concentrations in the air of pollen of the mentioned four taxa in particular years of the research period. Betula and Alnus discharged the greatest amount of pollen. In 1999 the great similarity of annual pollen sums of three taxa was recorded by means of the gravimetric method in all measurement points. Fagus was an exception, as its pollen concentration was much higher in the Roztocze region than in Lublin. In the case of Carpinus the enhanced pollen concentration was recorded in both study areas in 2002, and the highest concentration of Fagus occurred in 2003. During several years of studies we recorded great similarity of the obtained results in two study areas far apart.
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