Format: ORAL

Guillermo Guada, Mara Fernndez-Gonzlez, Rubn Amigo, Duarte A. Dias Lorenzo, Kenia C. Snchez Espinosa, F. Javier Rodrguez-Rajo

Department of Vegetal Biology and Soil Sciences, Faculty of Sciences, University of Vigo, 32004 Ourense, Spain

We studied the relationship between the occurrence of Betula spp. airborne pollen and climate, during the main pollen season, as well as before and in the preceding year. Our aim was to understand how environmental conditions can influence the main pollen season and the intensity of airborne pollen presence at the meridional boundary of the Betula forest distribution in Europe. For this purpose, pollen monitoring was conducted using Lanzoni VPPS 2000 volumetric trap and nearby meteorological data. The study area was located in the northwest of the Iberian Peninsula, specifically in three cities with diverse mesoclimate: Vigo (Atlantic), Ourense (Mediterranean) and Lugo (Cantabrian), which had a distinct oceanic influence. Aerobiological data was conducted based on the Spanish aerobiology network protocol. Weather variables precipitation, maximum, minimum and mean temperature were selected for three time windows: 1st the main pollen season period, 2nd from 5 to 90 days before the onset of pollen presence, with a cumulative five-day interval, and 3rd the average monthly climate of the previous year. Precipitation delays the onset of the main pollination season and also delays the end of the season, increasing pollen counts in the post-peak interval at all three areas. Temperature during the pollen season affects the duration and pollen integral differently among area. The pollen integral shows an increasing trend over the last decades at all three sites, and the increase in the minimum temperature of the previous summer explains this increase at all three areas from a climatic point of view. In conclusion, the effect of weather before and during the main pollen season has varied effects on the date-related data across the mesoclimate, while the increase in temperature during the summer of the last few decades results in a spring with higher airborne pollen loads for all three locations.