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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.
The pollinic spectrum of the Madeira region is dominated by grass pollen, which also represents an important aeroallergen in Europe. The present work aims to analyze the main features of the Poaceae pollen season in the Madeira region to determine the allergic risk. The study took place in Funchal city, the capital of Madeira Island, over a period of 10 years (2003–2012). The airborne pollen monitoring was carried out with a Hirst type volumetric trap, following well-established guidelines. In the atmosphere of Funchal, the mean annual Poaceae pollen index was 229. The mean Poaceae pollen season lasts 275 days, with an onset date in January/March and an end date in November/December. Poaceae counts showed a seasonal variation with 2 distinct peaks: a higher peak between March and June, and the second one in autumn. The peak values occurred mainly between April and June, and the highest peak was 93 grains/m3, detected on the 27th May of 2010. The Poaceae pollen remaining at low levels during the whole growing season, presenting a nil to low allergenic risk during most of the study period. Higher critical levels of allergens have been revealed after 2006. In general, the pollen risk from Poaceae lasted only a few days per year, despite the very long pollen season and the abundance of grasses in the landscape of Madeira Island.
This paper analyses pollen deposition in Lublin (Poland) and Skien (Norway). The studies were conducted in the years 1999 and 2000 using the gravimetric method and a Durham sampler. The study results varied both between years and cities. 10 more plant taxa were identified in Lublin than in Skien. In Lublin the highest airborne pollen concentrations were recorded in April, whereas in Skien in May and July. Betula, Pinaceae and Poaceae were the dominant taxa at the sampling site in Poland, while in Norway these were Pinaceae, Betula and Urtica. During the period of two years, annual pollen sums for most taxa were higher in the conditions of Poland, and the maximum pollen concentrations of Betula and Poaceae were higher in Poland, while for Pinaceae the pollen counts were higher in Norway.
Medical observations show that the level of pollinosis increased by 34.6% in central Russia in 2005–2012. This paper presents the results of 6-year pollen monitoring carried out with a Hirst-type pollen trap (Burkard Manufacturing Co. Ltd) between 2010 and 2015 in Perm Krai (Russia). Usually, sensitization of allergic people occurs in three periods: (i) spring due to the pollen of Betula, (ii) early summer due to Poaceae pollen, and (iii) late summer as a result of Artemisia pollen. Betula pollen, which is dominant (26.9–65.2% of total pollen counts), is recorded in large numbers in the period of flowering and occasionally during the entire period of pollination. Among herbaceous plants, the pollen of Poaceae, Urticaceae and Artemisia dominates in airborne pollen. The concentration of allergenic pollen grains in the air of Perm Krai is lower than in other European geographical regions.
Alder (Alnus Mill.), as an anemophilous species, produces large quantities of easily dispersed pollen. Annual pollen sums recorded in south-eastern Poland (by the volumetric method – Lanzoni trap) and in the area of the village of Guciów in the Central Roztocze region (pollen deposition in Tauber traps) were compared. The height at which the respective trap sites were located as well as local and regional vegetation and the distance from the nearest alder communities differ in both cases, likewise, the climate of these two regions differ. The analysed pollen data series cover the years 1998-2007 in Roztocze and 2001-2007 in Lublin. Large differences have been noted in Alnus pollen deposition values between particular years. Among them, there were observed years of very high annual sums (2001, 2003, 2006), as well as years of very low pollen deposition values in both regions (2002, 2005, 2007). In the period in question, the mean value of annual Alnus pollen count for Lublin was 5372 alder pollen grains in m3 of air, and in Roztocze 1647 grains per cm2 of area. During the seven-year period of monitoring (2001-2007), very similar trends were noted with respect to airborne alder pollen concentrations at both trap sites. Pollen data have been analysed against meteorological factors affecting alder pollen production and deposition. These are total precipitation and mean monthly air temperature in June, July and August in the year preceding pollen emission and the same weather elements in January and February in the year of pollen emission. In Roztocze a statistically signifi cant negative correlation has been found between Alnus pollen annual sums and total precipitation in August in the year preceding alder pollen emission and in February in the year of pollen emission. In both regions, the Spearman’s correlation coeffi cient does not show any statistically signifi cant values when comparing annual Alnus pollen sums with mean monthly temperatures of both January and February and summer months in the year preceding alder pollen emission.
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.
In 1997-1998, annual variations in the concentration of pollen in the atmosphere of Lublin, Poland, were analysed by the volumetric and gravimetric methods. To determine the concentration of pollen, a volumetric VST-trap was used, whereas for pollen fall - a gravimetric Durham trap. The following taxa were chosen for pollen analysis: Alnus, Corylus, Populus, Betula, Poaceae, Rumex, Plantago, Urtica, Chenopodiaceae and Artemisia. It was found that the length of pollen season, as well as pollen count increase and decrease tendencies determined by the two methods, were similar. Maximum concentrations of pollen grains occurred on the same dates for arboreous plants, Artemisia and Poaceae in 1997. In the case of other herbal plants, the maximum dates might be different, yet abundant occurrence of pollen grains was registered at the same time.
Birch pollen contains allergens belonging to those with the strongest allergenic properties. In order to trace pollen season patterns of this taxon and pollen annual sums at a wider regional scale, cooperation was established with the University of Latvia in Riga (Latvia). A comparison of the results obtained in the years 2003-2008 in Lublin and in Riga, using volumetric samplers, shows that there was a similar trend in the abundance of birch pollen. The highest sums were noted at both sites in 2003. In all the study years, more birch pollen grains were recorded in Lublin than in Riga, on the average by 7110. The birch pollen seasons started earlier in Lublin than in Riga, on the average by 6 days, and they ended earlier in Lublin, on the average by 18 days. In Riga the birch pollen seasons were longer and less abundant than in Lublin. In addition, in both the regions, i.e. in SE Poland (the Roztocze area) and in Latvia (the area of Marupe near Riga, Taurene, Teici and Rucava), there is pollen data series available obtained from annual pollen deposition monitoring conducted using the modified Tauber traps. These pollen counts have been carried out under the Pollen Monitoring Programme (http://pmp.oulu.fi) since 1998. The 11- year data series in Roztocze and the 10-year data series in Latvia allowed the trends in the occurrence of years of abundant or poor birch pollen release to be traced. In Roztocze maximum Betula pollen deposition occurred in the year 2003, in Latvia – in 1999. The absence of a significant correlation between SE Poland and Latvia with regard to the trends in the occurrence of years of abundant Betula pollen deposition induced the authors to seek climatic factors responsible for increased birch pollen production. The analysis of the Spearman’s rank correlation coefficients between annual Betula pollen sums in Roztocze and mean air temperature in June, July and August in the year preceding pollen emission as well as in spring (January-April) of the year of pollen emission showed a statistically significant negative correlation with air temperature in February of the year of pollen emission.
In Poland birch belongs to the most important taxa producing allergenic pollen, therefore information on the start dates, duration and severity of the pollen season is very important for allergists and their patients as well as for climatologists. Birch pollen monitoring was conducted in Lublin using the volumetric method during the period 2001-2010. A Lanzoni VPPS 2000 trap was placed at a height of 18 m in the city centre. The pollen season was determined using three methods: 98%, 95%, and 90%. The present study also investigated correlations between the birch pollen season parameters and meteorological factors. A comparison of the above-mentioned methods shows that, in the conditions prevailing in Lublin, the most appropriate method to determine the birch pollen season is the 98% method, since in the case of the two other methods too large quantities of pollen grains are eliminated. Based on a comparative analysis of the meteorological data from the study period and the long-term averages, it can be concluded that in the recent years a clear increase in air temperature has been recorded in Lublin. The study found a statistically significant negative correlation of seasonal pollen concentration with rainfall and air humidity. When the pre-peak and post-peak periods were separated, these correlations were larger and related to different meteorological factors. The start of the pollen season was negatively correlated with temperature in February and March. The season duration depended on temperature (a positive correlation). The date of the seasonal maximum was positively correlated with seasonal temperature and negatively with temperature in April.
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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