Comparative aerobiological study between two stations located at different points in a coastal city in Southern Spain

Due to the increase in allergies, aerobiological studies carried out in cities are essential to keep the population informed about the pollen atmospheric concentrations detected. However, the high cost and complexity of aerobiological studies often mean that the information is generated from a single sampling point that may not be representative of the entire city. In this study, the data obtained by two volumetric pollen traps, located in the coastal city of Malaga (Spain) were analyzed. One of the pollen traps was situated in the city center while the other was located on the city outskirts, 5 km away from the first. This was complemented with a meteorological and land use analysis to determine their influence on the pollen concentrations. Despite being located within the same city, the data obtained from both collectors showed significant differences in the relative abundance and annual integrals of the main pollen types, as well as in the periods in which elapse their main pollen seasons. These differences were more notable in the case of Amaranthaceae, Casuarina, Parietaria and Plantago pollen types due to the asymmetric distribution of green areas, agro-forestry areas and urban surfaces within the city, as well as the influence of local wind dynamics on the airborne pollen detected. Despite that, some differences were also observed in the other pollen types. For all the above, we consider that it is important to keep operational several sampling points in cities of a certain magnitude to provide more detailed information about atmospheric pollen concentrations.