Luigia Ruga

An integrated use of aerobiological and phenological data to analyse flowering in olive groves

Aerobiological and phenological investigation has been linked to analyse the flowering phenomena of olive (Olea europaea L.), a tree of economic importance, in Umbria, central Italy. Olive tree flowering was analysed by phenological observations in olive groves. Aerobiological monitoring was carried out with pollen traps that captured the pollen grains in the atmosphere by remote distances. This combined study of flowering was useful in overcoming the principal limit of phenological observations caused by their geographical narrowness. Eleven phenological stations in Perugia province were used and periodic observations were carried out during the flowering season. Two aerobiological stations located near the cities of Perugia and Spoleto were utilized to trap olive pollen grains in the atmosphere. Graphic and statistical analyses were used in order to study flowering dynamics, and to compare the methodological approaches. The phenological areas, according to their characteristics, were divided in two clusters each one related to a different pollen monitoring station. Statistical analyses showed the presence of a three ‐ four‐day period during which pollen released in the groves is persistent in the narrowness and resulted in a high correlation with the pollen monitored by the pollen traps. On the other hand, the phenological data considered along with the daily pollen concentrations permit the pollen peaks to be attributed to particular olive areas or olive cultivars. This demonstrates that both methodologies can be used effectively as integrated research tools in this kind of study.

Analysis of the potential fungal biodeteriogen effects in the “Doctorate Library” of the University of Perugia, Italy

Historical collections held in ancient archives and libraries constitute a cultural and artistic heritage of inestimable value. These collections contain a series of organic materials which may alter and perish in time, especially if they are conserved in inadequate environmental conditions and without any specific precautionary devices to protect them from damage caused by chemical, biological and physical factors. It is essential to prevent ‘at risk’ situations to conserve library and archive heritage. Early detection of fungal spores and moulds in conservation environments will permit us to intervene at the infection site at the right moment and also to detect the micro‐environments where climatic parameters are not suitable for conservation purposes. The aim of this study is to examine potentially biodeteriogen fungal micro‐flora in the environment of the “Doctorate Library”, one of the most important buildings of the University of Perugia, which contains frescos and library collection of great value. The study was carried out through quantitative and qualitative analysis of airborne fungal species and through the evaluation of viable aerobiological particles as potential agents of biodeterioration. The airspore monitoring was made using the active method (by Personal Volumetric Air Sampler Spore Trap, Burkard Company Ltd.) and the passive one (by sedimentation technique on Petri dishes). The results obtained by both methods allowed us to detect numerous potentially biodeteriogen species, to determine their quantity and influence and to evaluate the levels of their variability in time.

Phenological investigations of different winter-deciduous species growing under Mediterranean conditions

Phenological stages are the result of biorhythms and environmental factors, these last are probably the same ones that caused, during evolution, adjustments of the species to different climate. The present study was carried out in a Phenological Garden located in central Italy (Perugia, Umbria Region) which contains indicator species, common to all International Phenological Gardens. The aim of this study was to determine and analyse the average trends of development of eight plant species and their phenological adjustment to the Mediterranean environment, over a nine-year period (1997–2005). The results of the statistical analyses show a strong relationship between the temperature trends and vegetative seasonal evolutions interpreted by phenological data for all the species considered. Moreover, it was demonstrated that the plants studied may approach or close completely the timing gaps eventually created during the first phenological phases, adjusting thus the beginning of subsequent phenophases.RésuméLes stades phénologiques résultent des biorythmes et des facteurs environnementaux qui sont probablement ceux là même qui ont provoqué les changements d’aires de répartition des espèces pendant leur évolution, en réponse aux changements climatiques. La présente étude a été réalisée dans un Jardin phénologique situé dans le centre de l’Italie (Perugia, Ombrie) où l’on trouve des espèces indicatrices communes à tous les Jardins phénologiques internationaux. Le but de cette étude a été de déterminer et d’analyser les tendances moyennes de développement de huit espèces de plantes et leur ajustement phénologique à l’environnement méditerranéen, dans une période de neuf ans (1997–2005). Les résultats des analyses statistiques montrent une forte corrélation entre les tendances des températures et le développement végétatif saisonnier, pour toutes les espèces étudiées. On a également démontré que les plantes étudiées peuvent réduire ou éliminer les décalages temporels entre les premières phases phénologiques, en ajustant le début des phénophases suivantes.

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.

An applied aerobiological study to test the efficacy of pollen filters in limiting indoor pollen contamination

Abstract A simultaneous indoor and outdoor aerobiological monitoring was conducted to test the efficacy of a special pollen filter in impeding the entrance of aerobiological particles into living spaces and other structures marked by specific health needs. The efficacy levels of these membranes were tested through aerobiological monitoring carried out outdoors and indoors, in a special simulator located in the nearness and realised as a small-scale building model for simulating real indoor environments. The pollen monitoring carried out during approximately four months indicated a reduction in pollen concentration registered inside the special building simulator in comparison with the outdoor concentrations. The pollen reductions were different on the base of the different plant taxa. In particular, the highest percentages of reduction were recorded for the pollen of Poaceae and Cupro/Taxaceae (about 80%), while the lowest were those related to Urticaceae pollen (about 50%). These results can well be justified in consideration of the pollen size even if the artificial membranes were able to partially restrain the entering pollens utilising a special tissue with a uniform and consistent mesh width of about 70 μm, which is larger than the largest pollen deposited on the indoor monitoring apparatus.