Economic and Life Cycle Analysis of Passive and Active Monitoring of Ozone for Forest Protection

At forest sites, phytotoxic tropospheric ozone (O3) can be monitored with continuously operating, active monitors (AM) or passive, cumulative samplers (PM). For the first time, we present evidence that the sustainability of active monitoring is better than that of passive sensors, as the environmental, economic, and social costs are usually lower in the former than in the latter. By using data collected in the field, environmental, social, and economic costs were analyzed. The study considered monitoring sites at three distances from a control station in Italy (30, 400, and 750 km), two forest types (deciduous and Mediterranean evergreen), and three time windows (5, 10, and 20 years of monitoring). AM resulted in more convenience than PM, even after 5 years, in terms of O3 depletion, global warming, and photochemical O3 creation potential, suggesting that passive monitoring of ozone is not environmentally sustainable, especially for long time periods. AM led to savings ranging from a minimum of EUR 9650 in 5 years up to EUR 94,796 in 20 years in evergreen forests. The resulting social cost of PM was always higher than that of AM. The present evaluation will help in the decision process for the set-up of long-term forest monitoring sites dedicated to the protection of forests from O3

Trust me, I am the social media manager! Public sector communication’s trust work in municipality social media channels

Purpose: The study aims at investigating the role of social media managers (SMMs) as trust mediators and access points in the context of local government. Little empirical work is devoted to this issue and the purpose of the paper is to provide a better understanding of the trust work routines. Design/methodology/approach: This paper presents the results of a pilot study. Authors adopt a qualitative approach, using semi-structured in-depth interviews with a selected panel of PR professionals, managing social media channels on behalf of eleven Italian municipalities. Findings: SMMs are aware of having a key-role in nurturing trust, and trust is a design value of their work. This article shows many “signs of trust” that SMMs perceive as important to foster trust in the digital environment and in relations with citizens within the municipal context. Research limitations/implications: This pilot study draws upon a small sample and a single country-focus. Practical implications: The detected “signs of trust” can be useful for further investigations and provide SMMs with practical suggestions to integrate into their strategies. Originality/value: Two main fields – the use of social media and the impact on public sector communication and the institution/citizen trust relationships – are connected to the specific role played by SMMs: an emerging figure as yet little analyzed by scholars

NSKY-CD: A System for Cloud Detection Based on Night Sky Brightness and Sky Temperature

Cloud cover is important meteorological information that still requires expensive equipment to be monitored from the ground, especially at night. The use of artificial lights at night causes light pollution, and clouds amplify this by reflecting light downward. In addition, cloud thermal radiation emissions affect sky temperature. In this study, we describe a system (NSKY-CD) that can be used to detect clouds at night since it integrates a sky quality meter that measures night sky brightness (NSB) and an air temperature and an infrared temperature sensor that measure sky temperature. We defined a cloud detection method based on fixed threshold values determined with two different procedures that we called ‘optimal’ and ‘antimode’. We then quantitatively assessed the performance of these methods in detecting the presence or absence of clouds in the urban area of Florence during two full moon cycles. Accuracy for the ‘optimal’ method varied between 87% and 91%, while for the ‘antimode’ method, it varied between 86% and 89%. Our results suggest that the two parameters are complementary since NSB has a better performance on moonless nights, and the difference between air temperature and sky temperature has a better performance on moonlit nights. Our method can also be used to analyze historical series of NSB to estimate cloud presence backwards, thus providing important information for meteorological, environmental and astronomical studies

Impaired stomatal control is associated with reduced photosynthetic physiology in crop species grown at elevated [CO2]

Physiological control of stomatal conductance (Gs) permits plants to balance CO2-uptake for photosynthesis (PN) against water-loss, so optimising water use efficiency (WUE). An increase in the atmospheric concentration of carbon dioxide ([CO2]) will result in a stimulation of PN and reduction of Gs in many plants, enhancing carbon gain while reducing water-loss. It has also been hypothesised that the increase in WUE associated with lower Gs at elevated [CO2] would reduce the negative impacts of drought on many crops. Despite the large number of CO2-enrichment studies to date, there is relatively little information regarding the effect of elevated [CO2] on stomatal control. Five crop species with active physiological stomatal behaviour were grown at ambient (400 ppm) and elevated (2000 ppm) [CO2]. We investigated the relationship between stomatal function, stomatal size and photosynthetic capacity in the five species, and then assessed the mechanistic effect of elevated [CO2] on photosynthetic physiology, stomatal sensitivity to [CO2] and the effectiveness of stomatal closure to darkness. We observed positive relationships between the speed of stomatal response and the maximum rates of PN and Gs sustained by the plants; indicative of close co-ordination of stomatal behaviour and PN. In contrast to previous studies we did not observe a negative relationship between speed of stomatal response and stomatal size. The sensitivity of stomata to [CO2] declined with the ribulose-1,5-bisphosphate limited rate of PN at elevated [CO2]. The effectiveness of stomatal closure was also impaired at high [CO2]. Growth at elevated [CO2] did not affect the performance of photosystem II indicating that high [CO2] had not induced damage to the photosynthetic physiology, and suggesting that photosynthetic control of Gs is either directly impaired at high [CO2], sensing/signalling of environmental change is disrupted or elevated [CO2] causes some physical effect that constrains stomatal opening/closing. This study indicates that while elevated [CO2] may improve the WUE of crops under normal growth conditions, impaired stomatal control may increase the vulnerability of plants to water deficit and high temperatures

The functional significance of the stomatal size to density relationship: Interaction with atmospheric [CO2] and role in plant physiological behaviour

International audienc

La costa della Provincia di Sassari

L’analisi proposta dagli autori è particolarmente interessante per la Sardegna in quanto l’Isola, con circa 2000 km di coste comprese le isole minori, è la regione italiana con il maggiore perimetro costiero; le coste sono per lo più alte e a falesia (circa il 76 %). Le coste della Sardegna sono ben diverse da quelle della Penisola. L’unico litorale ampio e sicuro è quello di Cagliari, tutti gli altri sono: o archi sabbiosi con dune e stagni pa-lustri (un tempo malarici), o approdi chiusi da barriere montuose, o approdi rocciosi e ino-spitali, o piccoli porti naturali esposti al vento di Maestrale. Il primato di inviolabilità spetta alla costa orientale: una sorta di bastione ostile che intimorisce i naviganti e che solamente nella sua parte settentrionale si frastaglia in mille insenature e si frantuma in mille isolotti pericolosi a causa degli scogli sommersi. Certamente questa tipologia di costa, poco attrattiva, non ha favorito l’insediamento della popolazione isolana che si è progressivamente concentrata verso l’interno. Ciò ha, per contro, favorito l’insediamento di popolazioni allogene che si sono fermate, quando possibile, sulle coste proprio per non incontrare i barbari indigeni

Publisher Correction: Impaired photosynthesis and increased leaf construction costs may induce floral stress during episodes of global warming over macroevolutionary timescales.

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