Variación interanual y estacional del polen de Urticaceae en la atmósfera de San Miguel de Tucumán, Argentina

Background and Aims: In the atmosphere of San Miguel de Tucumán, Urticaceae pollen is relevant due to its abundance and permanence in the pollen cloud, as well as for its allergenic character. Quantitatively, it ranks third after Broussonetia papyrifera and Morus sp. This research aims to evaluate the changes in the concentration of Urticaceae pollen in order to establish its interannual and seasonal variation and its relationship with some meteorological parameters.Methods: Pollen capture was performed using a volumetric aerobiological sampler between the winter of 2008 and the autumn of 2016. Sample processing followed the standard method of the Spanish Aerobiology Network. Exploratory analysis and bivariate inferential analysis were performed to determine correlations between pollen concentrations and selected meteorological factors.Key results: Urticaceae pollen presented an annual average of 743.03 g/m3, which represents 11% of the total amount found in the analyzed period. The Main Pollination Period (PPP) varied between 58 and 232 days, starting in the months of August, September and November. The high spring tem-peratures combined with winter precipitation determine the anticipation of the PPP start date. The changes in the Urticaceae pollen load are related to the mean temperature and total precipitation recorded during PPP. Conclusions: Urticaceae is one of the best represented families in the pollen spectrum of the atmosphere of San Miguel de Tucumán. In addition to the meteorological parameters discussed in this research, other factors such as the changes in the amount and location of emitting sources, wind direction and CO2 concentrations, should be considered to better understand the annual and seasonal variations described in this work.