Long-Term Air Quality Assessment: Modeling Sources Contribution and Scenarios In Ivrea And Torino Areas

An evaluation of the air quality based on the combined use of monitoring data, dynamic emission inventories, and three-dimensional modeling has been performed in an area in North West Italy. Yearly maps of the pollutants of most concern have been produced by means of an Eulerian modeling system, run for two nested domains. The system is based on MINERVE diagnostic meteorological model, TREFIC (TRaffic Emission Factors Improved Calculation) traffic emission module, and farm air quality regional chemical-transport model. The zooming approach has allowed to correctly reproduce local concentrations in the small urban area in the inner domain as well as to quantify the role played by selected local sources respect to distant ones. The study of the impact of the future car fleet, pointing out the expected improvement for nitrogen oxides and the persisting problem of PM, provides a rationale for air quality governance.     

Response of zooxanthellae in symbiosis with the Mediterranean corals Cladocora caespitosa and Oculina patagonica to elevated temperatures

Scleractinian symbiotic corals living in the Ligurian Sea (NW Mediterranean Sea) have experienced warm summers during the last decade, with temperatures rapidly increasing, within a few days, to 3–4°C above the mean value of 24°C. The effect of elevated temperatures on the photosynthetic efficiency of zooxanthellae in symbiosis with temperate corals has not been well investigated. In this study, the corals, Cladocora caespitosa and Oculina patagonica were collected in the Ligurian Sea (44°N, 9°E), maintained during 2 weeks at the mean summer temperature of 24°C and then exposed during 48 h to temperatures of 24 (control), 27, 29 and 32°C. Chlorophyll (chl) fluorescence parameters [F _v/F _m, electron transport rate (ETR), non-photochemical quenching (NPQ)] were measured using pulse amplitude modulated (PAM) fluorimetry before, during the thermal increase, and after 1 and 7 days of recovery (corals maintained at 24°C). Zooxanthellae showed a broad tolerance to temperature increase, since their density remained unchanged and there was no significant reduction in their maximum quantum yield (F _v/F _m) or ETR up to 29°C. This temperature corresponded to a 5°C increase compared to the mean summer temperature (24°C) in the Ligurian Sea. At 32°C, there was a significant decrease in chl contents for both corals. This decrease was due to a reduction in the chl/zooxanthellae content. For C. caespitosa, there was also a decrease in ETR_max, not associated with a change in F _v/F _m or in the non-photochemical quenching (NPQ); for O. patagonica, both ETR_max and F _v/F _m significantly decreased, and NPQ_max showed a significant increase. Damages to the photosystem II appeared to be reversible in both corals, since F _v/F _m values returned to normal after 1 day at 24°C. Zooxanthellae in symbiosis with the Mediterranean corals investigated can therefore be considered as resistant to short-term increases in temperature, even well above the maximum temperatures experienced by these corals in summer.     

Competition for the home and aggressive behaviour in the chiton Acanthopleura gemmata (Blainville) (Mollusca: Polyplacophora)

Summary Computerized screening of all the positions recorded during a synodic month on 120 individually marked chitons (Acanthopleura gemmata) pinpointed their preferential resting points. Unlike the majority of intertidal chitons so far studied, A. gemmata rests in well-defined homes actively dug in the rock. Homes proved to be not strictly individual and periodically interchangeable. A complex aggressive behaviour was recorded in the field when two animals came in contact at home. When competing for ownership of a resting site rival chitons may suppress their nocturnal feeding activity. Despite its strong home-related territoriality A. gemmata showed no mutual exclusion on the feeding area. The highly specialized resting habits clearly protects A. gemmata from its most important predator, the toad fish Arothron immaculatus. The behaviour of A. gemmata is compared to that of other chitons and gastropods, and the current hypotheses concerning the adaptive value of the homing behaviour in littoral molluscs are discussed.     

Analysis of heavy metals in atmospheric particulates in relation to their bioaccumulation in explanted Pseudevernia furfuracea thalli

Lichens explants and airborne particulates were analysed for Cr, Zn, Cd, Pb, Ni, Fe, Mn and Cu content in a rural site in the province of Vercelli (Piedmont, N. Italy). Thalliof the fruticose lichen Pseudevernia furfuracea were collected from an uncontaminated area and exposed for one yearusing two different techniques. Particulates were collected using a continuously operating particulate sampler set up nearthe lichens explanted throughout the experiment survey.The results confirm both the importance of assessing contamination in rural areas corroborated by the analysis of the presence of the heavy metals in particulates in relationto the main wind directions and the validity of this lichen asbiomonitor of airborne metal pollution, although meaningfuldifferences were pointed out between the two different techniques of exposure. The significant correlation between most of the metals accumulated by lichens and the metal air concentrations shows a good evidence of their ability to represent atmospheric contamination.     

Thermodynamics of irreversible processes and quantum field theory: An interplay for the understanding of ecosystem dynamics

Ecological modelling has not yet received from basic “hard” sciences, like conventional physics and chemistry, an adequate conceptual support. Mechanistic simulation techniques are very far from achieving a satisfactory understanding of ecosystem dynamics.     

Glacier response to current climate change and future scenarios in the northwestern Italian Alps

We analyze longtime series of annual snout positions of several valley glaciers in the northwestern Italian Alps, together with a high-resolution gridded dataset of temperature and precipitation available for the last 50 years. Glacier snout fluctuations are on average negative during this time span, albeit with a period of glacier advance between about 1970 and 1990. To determine which climatic variables best correlate with glacier snout fluctuations, we consider a large set of seasonal predictors, based on our climatic dataset, and determine the most significant drivers by a stepwise regression technique. This in-depth screening indicates that the average glacier snout fluctuations strongly respond to summer temperature and winter precipitation variations, with a delay of 5 and 10 year, respectively. Snout fluctuations display also a significant (albeit weak) response to concurrent (same year) spring temperature and precipitation conditions. A linear regressive model based on these four climatic variables explains up to 93 % of the variance, which becomes 89 % when only the two delayed variables are taken into account. When employed for out-of-sample projections, the empirical model displays high prediction skill, and it is thus used to estimate the average glacier response to different climate change scenarios (RCP4.5, RCP8.5, A1B), using both global and regional climate models. In all cases, glacier snout fluctuations display a negative trend, and the glaciers of this region display an accelerated retreat, leading to a further regression of the snout position. By 2050, the retreat is estimated to be between about 300 and 400 m with respect to the current position. Glacier regression is more intense for the RCP8.5 and A1B scenarios, as it could be expected from the higher severity of these emission pathways.     

Governance objectives and instruments,ecosystem management and biodiversity conservation: the Chianti case study

The complex relationships between governance processes, ecosystem management and biodiversity conservation are receiving growing attention by the scientific community. The scope of research in this field is generally that of identifying main governance factors leading to success or failure in the sustainable management of ecosystems and biodiversity conservation, so to develop appropriate sectoral and intersectoral policies fostering sustainable use of natural resources. In this paper, a methodological approach is first presented and then applied to analyse the impacts of agriculture and rural policies on agro-ecosystem services and biodiversity conservation in the central hills of Tuscany, the Chianti area. This approach is focusing in particular on governance objectives and instruments used in the management of ecosystem services. A share-farming system based on multifunctional agriculture ruled Chianti until World War II. Then, after the abandonment of rural areas by share-farmers, governance objectives and ecosystem management were oriented towards the production of commodities such as wine and olive oil almost ignoring the provision of public goods such as soil erosion and water run-off control and biodiversity conservation. In order to achieve a more sustainable ecosystems management in Chianti, there is the need to develop a multifaceted governance strategy to reward appropriately the supplying of environmental goods and services by farmers.     

Accelerated carbonation of wood combustion ash for CO<Subscript>2</Subscript> removal from gaseous streams and storage in solid form

In this work, ash generated by the combustion of wood in a central heating plant was used to remove and permanently store by accelerated carbonation CO₂ contained in a gas mixture simulating biogas. The process was studied as an alternative treatment to the ones currently available on the market for biogas upgrading. The process was investigated at laboratory scale by setting up a facility for directly contacting the wood ash and the synthetic biogas in a fixed bed reactor. The process was able to completely remove CO₂ during its initial phase. After about 30 h, CO₂ started to appear again in the outlet stream and its concentration rapidly increased. The specific CO₂ uptake achieved in solid carbonate form was of about 200 g/kg of dry wood ash. This value is an order of magnitude higher than the ones found for waste incineration bottom ash carrying out similar experiments. The difference was ascribed to the physicochemical properties of the ash, characterized by a fine particle size (d₅₀ <?0.2 mm) and high content of reactive phases with CO₂ (e.g., Ca hydroxides). The leaching behavior of the wood ash was examined before and after the accelerated carbonation process showing that the release of several elements was lower after the treatment; Ba leaching in particular decreased by over two orders of magnitude. However, the release of the critical elements for the management of this type of residues (especially Cr and sulfates) appeared not to be significantly affected, while V leaching increased.