Airborne pollen trends in T étouan (NW of Morocco)

AbstractTrends of the airborne annual pollen integral (APIn) and pollen season of principal woody and herbaceous plants in T étouan were analysed over a 10-year monitoring period (2008–2017). Pollen was continuously sampled by means of a 7-day recording volumetric pollen trap by Burkard. Pollen trends were analysed by using Mann–Kendall tests and Sen’s slope. Aerobiological data were correlated with temperature and rainfall. A significant decreasing trend in annual minimum temperature was revealed together with significant decreasing trends in the APIn observed for Cupressaceae,Cannabis,Parietaria,Pinus andQuercus, this being highly significant for Cupressaceae andPinus. On the contrary, the seasonal intensity ofMercurialis,Morus andOlea showed nonsignificant trends. Besides this, 77% of the studied pollen types showed a tendency to decreasing the peaks value, these trends being significant for Cupressaceae ( −204.67 pollen/ m3 per year) andPinus ( −14.33 pollen/ m3 per year). The end of theQuercus pollen season showed a marked tendency to occur earlier across the years ( −4.5 days/year) and the start day ofCannabis, Cupressaceae,Pinus and Poaceae to occur later (+  7.13, 2.33, 1.67 and 2.5 day/year, respectively), shortening the duration of the respective pollen seasons but not with a significant trend. Regarding the association between the pollen season intensity and meteorological parameters, six pollen types showed at least one statistically significant c...
Source: Aerobiologia - Category: Environmental Health Source Type: research