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The occurrence of airborne fungal spores is driven by several biogeographic and climatic factors. In addition, the occurrence of fires near fungal ecosystems seems to play an important role on the aerobiology of fungal spores. Wildfires are prevalent throughout the world and particularly so in several South European countries with Mediterranean climate. The present survey aimed at analysing the impact of urban and forest fires on the airborne fungal spore content of Madeira Island. Data suggest that after a fire occurrence, the concentration of fungal spores tends to increase in the air, peaking on the 10th day after a fire event. It is likely that fire-induced convections promote release of fungal spores from their natural habitat and that the soil heating conditions could trigger the germination of fungi colonizing post-fire plant residues and soil. It is also possible that the registered low precipitation and wind intensity could help increase the concentration of fungal spores in the atmosphere during 1–2 weeks. These findings need further research, not only at a regional but also at a larger scale, in order to clarify the specific impact of fires on such biological particles and the possible consequences on public health.

This study presents the findings of a 10-year survey carried out by the Portuguese Aerobiology Network (RPA) at seven pollen-monitoring stations: five mainland stations (Oporto, Coimbra, Lisbon, Évora and Portimão) and two insular stations [Funchal (Madeira archipelago) and Ponta Delgada (Azores archipelago)]. The main aim of the study was to examine spatial and temporal variations in the Annual Pollen Index (API) with particular focus on the most frequently recorded pollen types. Pollen monitoring (2003–2012) was carried out using Hirst-type volumetric spore traps, following the minimum recommendations proposed by the European Aerobiology Society Working Group on Quality Control. Daily pollen data were examined for similarities using the Kruskal–Wallis nonparametric test and multivariate regression trees. Simple linear regression analysis was used to describe trends in API. The airborne pollen spectrum at RPA stations is dominated by important allergenic pollen types such as Poaceae, Olea and Urticaceae. Statistically significant differences were witnessed in the API recorded at the seven stations. Mean API is higher in the southern mainland cities, e.g. Évora, Lisbon and Portimão, and lower in insular and littoral cities. There were also a number of significant trends in API during the 10-year study. This report identifies spatial and temporal variations in the amount of airborne pollen recorded annually in the Portuguese territory. There were also a number of significant changes in API, but no general increases in the amount of airborne pollen.