Magnetic and chemical biomonitoring methodologies were applied to the southern slopes of the Palatine Hill archaeological area in Rome, Italy. Plant leaves and lichen transplants were respectively ...sampled and exposed between July 2022 and June 2023 to assess the impact of vehicular particulate matter from Via dei Cerchi, a trafficked road coasting Circus Maximus, towards the archaeological area upon the Palatine Hill. The magnetic properties of leaves and lichens, inferred from magnetic susceptibility, hysteresis loops and first order reversal curves, were combined with the concentration of trace elements. It was demonstrated that the bioaccumulation of magnetite-like particles, associated with tracers of vehicular emissions, such as Ba and Sb, decreased with longitudinal distance from the road, without any important influence of elevation from the ground. Lichens demonstrated to be more efficient biomonitors of airborne PM than leaves, irrespective of the plant species. Conversely, leaves intercepted and accumulated all PM fractions, including road dusts and resuspended soil particles. Thus, plant leaves are suitable for providing preventive conservation services that limit the impact of particulate pollution on cultural heritage sites within busy metropolitan contexts.
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•Multidisciplinary biomonitoring of vehicular PM was applied at the Palatine Hill archaeological area.•The main factor affecting bioaccumulation of vehicular PM is longitudinal distance from road.•Leaves accumulate airborne and resuspended PM, providing preventive conservation services.•Lichen transplants are superior to tree leaves as biomonitors of airborne PM.
Internet of Things (IoT) technologies can facilitate the preventive conservation of cultural heritage (CH) by enabling the management of data collected from electronic sensors. This work presents an ...IoT architecture for this purpose. Firstly, we discuss the requirements from the artwork standpoint, data acquisition, cloud processing and data visualization to the end user. The results presented in this work focuses on the most critical aspect of the architecture, which are the sensor nodes. We designed a solution based on LoRa and Sigfox technologies to produce the minimum impact in the artwork, achieving a lifespan of more than 10 years. The solution will be capable of scaling the processing and storage resources, deployed either in a public or on-premise cloud, embedding complex predictive models. This combination of technologies can cope with different types of cultural heritage environments.
•IoT architecture proposal specific for Heritage Preservation need.•Sensor node life-span of 20 years without battery replacement.•Wireless technology based on subGHz bands capable of passing through tick walls.•Stand-alone sensor based on Sigfox for direct connection to the cloud.•Evaluation done for typical RH and temperature monitoring needs and based on Italian, European and American standards.•All kind of artwork containers covered: single isolated artwork, typical artwork containers (museums, churches, etc.), power supply constrained sites (open-air archaeological sites, etc.).
Magnetic biomonitoring methodologies were applied at Villa Farnesina, Rome, a masterpiece of the Italian Renaissance, with loggias frescoed by renowned artists such as Raffaello Sanzio. Plant leaves ...were sampled in September and December 2020 and lichen transplants were exposed from October 2020 to early January 2021 at increasing distances from the main trafficked road, Lungotevere Farnesina, introducing an outdoor vs. indoor mixed sampling design aimed at assessing the impact of vehicular particulate matter (PM) on the Villa Loggias. The magnetic properties of leaves and lichens - inferred from magnetic susceptibility values, hysteresis loops and first order reversal curves - showed that the bioaccumulation of magnetite-like particles, associated with trace metals such as Cu, Ba and Sb, decreased exponentially with the distance from the road, and was mainly linked to metallic emission from vehicle brake abrasion. For the frescoed Halls, ca. 30 m from the road, the exposure to traffic-related emissions was very limited or negligible. Tree and shrub leaves of the Lungotevere and of the Villa's Gardens intercepted much traffic-derived PM, thus being able to protect the indoor cultural heritage and providing an essential conservation service. It is concluded that the joint use of magnetic and chemical analyses can profitably be used for evaluating the impact of particulate pollution on cultural heritage within complex metropolitan contexts as a preventive conservation measure.
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•Magnetic biomonitoring methodologies were successfully applied at Villa Farnesina, Rome.•The bioaccumulation of vehicular PM decreases with distance from a major road.•Roadside leaves accumulate PM, providing preventive conservation services.•Lichen transplants are suitable for investigating the diffusion of PM indoors.•Villa Farnesina frescoed Halls are preserved from vehicular metallic emissions.
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Materials and colloids science can provide significant contributions to the conservation of Cultural Heritage. Hybrid systems made of a castor oil-derived polymeric network and a ...disperse phase of zinc oxide particles (ZnO/COPs) can be more effective absorbers of acetic acid (AcOH, a major pollutant harmful to artifacts in museums and art collections) than state-of-the-art materials, provided the acid uptake mechanism by the hybrids is elucidated and optimized. The starting hypothesis was that the polymer matrix might act as transporter, while acid adsorption would take place at the ZnO particles surface. The effect of particles size was expected to play a significant role.
The adsorption kinetics of the hybrids were studied in the 23-45˚C range, in comparison with activated charcoal, the benchmark employed by conservators. Morphological and fractal dimension of ZnO micro- and nano-particles in the hybrid networks were investigated and correlated to the adsorption kinetics.
The presence of a two-steps mechanism for AcOH uptake by the hybrids was demonstrated for the first time: a combination of Fickian diffusion and Case-II transport occurs in the COP matrix, and adsorption dominates acid uptake (followed by neutralization) at the particles surface. This mechanism is likely key to explain the enhanced performances of the hybrids vs activated charcoal and state-of-the-art tools to remove AcOH. The hybrids have high uptake capacity, and lower activation energies for the removal process than materials where the uptake of acid relies solely on adsorption. The size of the ZnO particles contributes to the process, i.e. nanoparticles form smaller and ramified fractal clusters that are able to adsorb AcOH more effectively than microparticles. These insights demonstrated the efficacy of the novel hybrids in art conservation, where the control of minimal concentrations of VOCs is crucial for the preventive conservation of masterpieces, and can be useful to other fields where efficient capture of acetic acid is critical (food industry, textile dyeing/printing, etc.).
El presente artículo describe el estado de conservación del edificio La Quinta desde el dictamen patológico y la valoración de riesgos, con la finalidad de conformar el plan de conservación ...preventiva, según metodologías internacionales. Se recurre al análisis de riesgo, amenaza y vulnerabilidad mediante la matriz de Leopold. A nivel patológico presenta: (a) 2 % de afección en cielo raso, (b) 7 % en mampostería, (c) 1.5 % de afección en pisos, y (d) 2.06 % en cubierta. Si bien predominan las afecciones asociadas a la presencia de agua, existen otros factores de deterioro como la vegetación parásita, la acción antrópica y el desuso, que desembocan en 4 acciones emergentes, 26 acciones correctivas y 21 acciones de mantenimiento.
This paper tells us a complex story on the historic evolution of preventive conservation of architectural heritage in Italy. Firstly, it introduces Cesare Brandi's Theory of Restoration, pointing out ...the peculiar sense of the word Restoration in Brandi's system other than the common sense in the international discourse, the limits of Brandi's theory to architectural conservation and his prophecy on preventive restoration. Then it talks about the different framework and practices of preventive conservation in the field of built heritage compared to the museum sector, the milestone of Giovanni Urbani's pilot project on programmed conservation and the leading role of the Risk Map of Cultural Heritage. Finally, based on the discussions of the durable change in the architectural conservation field after the Venice Charter, including the teaching in Milan School, the debate and re-definition of architectural conservation and the advance definitions of conservation, prevention, maintenance and restoration in the 2004 National Code of Cultural Heritage and Landscape, it gives us an agenda for future trends of planned conservation with aims to conserve the material authenticity and promote the co-evolutional strategy.
Both the indirect control of microclimate conditions and the direct application of preservative products to contrast stone bioreceptivity may contribute to limit lithobiontic recolonization of ...cultural heritage surfaces after cleaning interventions. However, the priority deserved by these different preventive approaches has still been poorly evaluated, particularly in outdoor environments. This work dealt with the engraved sandstone surfaces of the National Park of Rock Engravings of Naquane (Italy, UNESCO WHS), widely colonized by lichens, mosses and a dark cyanobacterial biofilm, and thus requiring frequent cleaning interventions to preserve their legibility for visitors and scholars. In particular, post-cleaning recolonization by the different lithobionts was seasonally monitored along 54 months in different zones of an engraved outcrop, primarily differing in levels of shading, on parcels exposed to nine different conservative treatments. These included (or not) a pre-cleaning devitalization of lithobionts and the post-cleaning application of biocidal (benzalkonium chloride, plant essential oils, usnic acid) and other restoration products (nanocrystalline anatase, polysiloxane-based water repellent, ethyl-silicate-based consolidant). The combination of surface image analyses, fluorimetric and colorimetric measurements showed that mosses and the cyanobacterial biofilm rapidly recolonized all the parcels in the more shaded zone, irrespective of conservative treatments. In the other areas, recolonization significantly differed depending on the treatment. The post-cleaning application of biocides determined the best results through two vegetative seasons, but only nanocrystalline anatase and the polysiloxane-based water repellent maintained the surfaces lighter than uncleaned controls along the whole monitoring period. Recolonization primarily proceeded by the uncleaned surfaces surrounding the parcels and, at least in the examined case of lichens, did not show substantial shifts in community composition, although some nitrophytic species increased their frequency. In conclusion, the effectiveness of preservative treatments to prevent a rapid recolonization of heritage stone surfaces appeared subordinate to the presence of microenvironmental conditions less favourable to lithobionts.
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•Biofilms, mosses and lichens monitored by image analysis, fluorimetry and colorimetry.•Effectiveness of preservative treatments dependent on microenvironmental conditions•Lowest after cleaning re-darkening with polysiloxane water repellent and nano-anatase•Delayed recolonization also with the application of synthetic and natural biocides•No change in lichen diversity but increased nitrophytic species after some treatments.
This work presents an approach for the preventive conservation of historical constructions by means of Historical Building Information Modelling (HBIM) strategies. To this end, the methodology ...exploits the latest advances in inspection protocols, digitalization tools -by means of the novel back-pack mapping systems- as well as wireless monitoring networks. All this information is integrated in the HBIM environment by using ad-hoc families and interoperable communication protocols that allow obtaining a complete knowledge of the conservation status of the site. Additionally, the approach uses key performance indicators in order to evaluate the environmental conditions of the different assets presented in the site. All these features have been validated in one of the most representative heritage buildings in Spain: The General Historical Library of the University of Salamanca.
•A novel HBIM platform for heritage preventive conservation is presented.•The combination of IoT and remote sensing strategies is exploited for conservation.•KPI has been introduced inside the HBIM environment.•A wearable mobile mapping system is used for generate the as-built model.•The protocol is validated in one of the most outstanding heritage building in Spain.
In the Armenian context, most of the architectural heritages are monasteries often subjected to geological hazards and degradation of materials due to the environmental conditions. The aim of this ...study, in collaboration between the Ca’ Foscari University of Venice and the National University of Architecture and Construction of Armenia, was a preliminary analysis of the state of conservation of the UNESCO heritage site of Geghard Monastery. Specifically, this research reports the results of the multi-disciplinary investigation on the internal stone surfaces of the caved "Proshian family room" belonging to the XIII century. In situ analyses that consisted of a careful visual survey of the stone surface, environmental monitoring, water absorption and ultrasonic measurements were conducted.The collected data constitute a starting point for monitoring the degradation phenomena, which is helpful for future preventive conservative interventions.
•Long-term monitoring of microclimatic parameters in a historic building.•Risk-based analysis to evaluate degradation phenomena.•Hygrothermal capacity of historic buildings to achieve microclimatic ...targets.•Real risks associated to natural indoor climates in temperate climate.•New classification to evaluate degradation risks and building response.
Historic buildings are usually characterized by a particular microclimate due to their high thermal inertia that may require the use of mechanical systems to control the environment. The guidelines used to define the indoor climate have evolved in recent years, with new methods and deepening the knowledge of the behaviour of materials, resulting in the publication of several risk-based methods.
Despite the risk-based methods, the use of guidelines continue to play a leading role on the science of preventive conservation with the progressive assumption of less demanding targets. However these guidelines were usually defined for specific climates so that when extrapolated to other locations their application may not be positive.
This research aims to analyze the hygrothermal behaviour of an unheated historic building in a temperate climate (Lisbon, Portugal) using a long-term monitoring and applying a risk-based analysis to the natural climate and to the climate limited by the historic set-point of 20°C – 50% and the targets defined by the standards EN 15757 and PAS 198. Finally a classification was defined to assist in the decision-making processes and to verify if it is safe to impose less demanding targets in temperate climates, improving therefore energy economy.
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