RESUMO
The aim of the study was to determine the characteristics of temporal and space-time autocorrelation of pollen counts of Alnus, Betula, and Corylus in the air of eight cities in Poland. Daily average pollen concentrations were monitored over 8 years (2001-2005 and 2009-2011) using Hirst-designed volumetric spore traps. The spatial and temporal coherence of data was investigated using the autocorrelation and cross-correlation functions. The calculation and mathematical modelling of 61 correlograms were performed for up to 25 days back. The study revealed an association between temporal variations in Alnus, Betula, and Corylus pollen counts in Poland and three main groups of factors such as: (1) air mass exchange after the passage of a single weather front (30-40 % of pollen count variation); (2) long-lasting factors (50-60 %); and (3) random factors, including diurnal variations and measurements errors (10 %). These results can help to improve the quality of forecasting models.
RESUMO
The aim of the study was to compare the airborne concentrations of allergenic pollen produced by three early flowering tree taxa (Corylus, Alnus, Betula) in the cities of Warsaw (central Poland), Lublin (eastern Poland) and Szczecin (western Poland) during the years 2000-2001. Measurements were performed by the volumetric method. Pollen seasons were defined as the periods in which 95% of the total catch occurred. The highest concentration and annual pollen count of Corylus was measured in Lublin in both seasons, while the highest annual pollen counts of Alnus and Betula were noted in Warsaw, where the annual pollen count of Betula in 2001 was four times higher than in 2000 and equalled 5,376 grains in m3 per 24 h. Significant differences in the pollen count of the examined taxa were observed between two seasons: the pollen count of Corylus was higher in 2000 than in 2001, while for Alnus and Betula the opposite was the case. The longest pollen seasons were observed at low annual pollen counts for the pollen of Corylus. Results of the study reveal significant differences between the seasons and the cities. The differences concern the dates of the appearance of pollen grains in the air, the duration of the presence of sporomorphs and the maximum concentrations in particular seasons. The pollen counts of alder, birch and hazel trees are determined by the weather, diversity of local flora and specific rhythm of pollination of particular taxa.