Environmental factors affecting the start of pollen season and concentrationsof airborne Alnus pollen in two localities of Galicia (NW Spain).
Victoria Jato 1, Angeles Dopazo 1, Francisco Javier Rodriguez-Rajo 2 1 - 2 - Dr. F. Javier Rodriguez Rajo, University of Vigo, Sciences Faculty of Ourense,Department of Plant Biology and Soil Sciences, Ourense 32004, Spain. firstname.lastname@example.org Ann Agric Environ Med 2004; 11 (1): ICID: 142691
Alnus pollen is an early component of the annual atmospheric aerosol ofthe north-west regions of Spain, which causes the first occurrence of allergic symptoms. Seasonal andintra-daily variation of Alnus pollination, and the influence that main meteorological parameters exert,was studied in this paper. Monitoring was carried out from 1993-2002, by using two Lanzoni VPPS 2000volumetric samplers. Once the atmospheric behaviour of this pollen had been identified, the final objectivewas to elaborate predictive models to determine the onset of the Alnus pollen season and its concentrationsduring the pollination period in two localities of north-west Spain (Santiago and Ourense). Winter chillingrequired to overcome the bud-dormancy period was similar in both cities, with around 800 Chilling Hours(C.H.) and 5.5 degrees C threshold temperature. Calculation of heat requirement for bud growth was carriedout with maximum temperature, with around 50 Growth Degree Days (G.D.D. degrees C) needed, with 6 degreesC threshold temperature. Data from 2002 were used in order to determine the real validity of the models.This year was not taken into account to establish the aforementioned models. The variation between thepredicted start of the pollen season and the observed season was smallest in Ourense. Verifying the proposedmodels for predicting daily mean concentrations of Alnus pollen during the pollen season shows that thepredicted curves fits the observed variations of daily mean concentrations.