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Cupressaceae is one of the most widespread families in the Mediterranean region, widely used as ornamental trees both in cities and extra urban areas. The family is also known to produce a considerable amount of pollen grains. Nevertheless, Cupressaceae pollen is generally scarce in sediments and it is attested to be one of the most underrepresented pollen in ancient spectra. Cupressaceae pollen diffusion was detected by means of two sampling methods: moss cushions, which are able to accumulate pollen grains for several successive years, and volumetric sampler, which records the airborne pollen day by day. The study was conducted in the city of Florence (Italy), repeating moss samplings at the same sites for three times. The comparison between the two sampling methods revealed the low preservation of this pollen type and suggested that even low quantities of this pollen may indicate the local presence of the source plants. In order to test the contribution of the local pollen sources to the background of the airborne pollen, the pollen content of moss cushions was also related to the number of Cupressaceae plants surroundings each sampling site. The results indicate a noticeable influence of the plants growing in a short-range distance. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]