The distribution of Ambrosia spp. pollen grains through North East of Italy, Slovenia and Carinthia (Austria) in the year 2021

Introduction The data sharing of Ambrosia spp. pollen particles detection among the Environmental Agencies of North East Italy, Carinthia (Austria) and Slovenia has allowed the development of a geographical map showing where ragweed was mostly concentrated in 2021. Materials and Methods Ambrosia spp. pollen grains were identified during the routine microscope analysis of the samples collected in 2021 from n.24 stations belonging to the monitoring networks of the Environmental Agencies involved in the study. Specific training in the recognition of Ambrosia spp pollen was previously carried out to distinguish it from similar genera. Pollen concentration data collected from each station were reported as annual pollen index, i.e. the sum of daily pollen concentration over the year (fig.1). Kriging model was applied to spatialize the punctual annual data and visualize the areas of greatest presence of the pollen. Results and Discussion The annual pollen indexes of Ambrosia spp. from North East of Italy, Carinthia (Austria) and Slovenia, spatialized with the Kriging method are represented in figure 2. On this map, the sampling stations are also reported and since each station represents the main phytoclimatic areas of each territory, it was possible to validate the result obtained. It is evident a higher concentration of Ambrosia pollen in the eastern-south part of the study are