Plant phenological observations in rural and industrial central Italy areas.

The physiological stress caused by particular pollution conditions can result in phenological phase shifts that can include a block in vegetative or reproductive development. The main aim of the present study was to determine and analyse the mean development trends of some winter deciduous species in comparison to the climate tendencies, as calculated within two phenological gardens in the Arezzo and Perugia areas of central Italy. Moreover, a phenological comparison between the guide species of the two phenological gardens, one located in an industrial area, and the other in a farming area, was carried out. The phenological evidences showed significant phase displacements for the common guide species present in both the gardens which however may be explained by the meteorological performances above all in the Perugia not polluted area. In these terms, there were no evident phenological effects on the plants from the industrial area pollutants in the Arezzo garden. Moreover, also the temperature reduction tendencies at the end of spring not influenced significantly the phenological behaviours of the plant species not inducing them toward a predictable delay of reproductive and adult leaves phases.