Comparing pollen data from moss cushions and a volumetric sampler: the study in the city of Florence (Italy)

In Italy, aerobiological monitoring is usually carried out by the regional agencies for environmental protection (ARPA [Agenzia Regionale per la Protezione Ambientale]) using volumetric samplers. Another widespread method for the study of airborne pollen is the analysis of moss cushions, generally used to relate pollen rain to flora and vegetation. In this study, we compare the data coming from these two pollen monitoring methods: volumetric samplers and moss cushions. The study was carried out in the city of Florence (Italy) and took into consideration two different spans of time. The two pollen monitoring methods show quantitative and qualitative differences. The main discrepancy seems to be the direct consequence of the different preservation time of the grains in the moss cushions depending on the features of the pollen grains. The study also provides an estimate of the period of pollen accumulation and preservation in moss cushions, which turned out to be more than five years. The two sampling methods furnish complementary information; volumetric samplers especially suited for aerobiological studies and moss cushions for environmental and palaeobotanical research.