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Like other hypogeal environments, the Roman Houses of the Caelian Hill are prone to unwanted biological growth. Wide conservative interventions have been carried out at the beginning of this millenium to reduce biodeterioration and physical–chemical damages. Retracing the last monitoring work, we assessed the site’s current state of conservation and biodeterioration intending to check the previous treatments’ effectiveness and deepen the common knowledge of the subterranean biota and their possible biodeteriogenic effects. Starting from the past test areas and the previous identifications of the occurring biodeteriogens, we further isolated and identified the main eubacterial, fungal, and phototrophic settlers, focusing on some detrimental traits for wall paintings (i.e., acid production and carbonate precipitation). The achieved results proved the success of the performed interventions in reducing the wall’s water content. Otherwise, the new conditions raise, in the long term, new concerns about lampenflora, carbonate precipitations, and salt efflorescence. Here, the Caelian Houses’ new status is documented. The possible favouring conditions for the different groups of biodeteriogens, along with the taxonomical novelties, additional risks tied to the anthropization of the resident culturable microbial community, and the possible relation between the black fungus Cyphellophora olivacea and roots, are reported and discussed.

Archaeological areas often become hotspots for biodiversity and refugia for plant species. The management activity of a site permits the conservation of natural habitats. This first contribution to the floristic assessment of an Iranian archaeological site, aims to preserve its natural values. The Pasargadae World Heritage Site (sixth century BC) located at the border between the Zagros mountains and the Irano-Turanian region, showed a richness of 244 species, belonging to 38 families and 163 genera. The most represented families are Asteraceae (56), Poaceae (34) and Fabaceae (22). Herbaceous species represented 90% of the flora [therophytes (42%), hemicryptophytes (39%) and geophytes (9%)]. Asiatic, Irano-Turanian and Mediterranean species are the most recurrent species with a high component of endemic ones. Astragalus ghashghaicus, Taraxacum plicatulum, Acantholimon serotinum and Linaria farsensis were among the more interesting floristic elements. The comparison with past data, even if limited in quantity, indicated a good floristic conservation status. This research also showed the need to deepen our knowledge of the taxonomic features of this Iranian flora, sometimes still resulting in an ambiguous or unresolved status. The collected floristic data will help in elaborating management protocols, to enhance the cultural and natural value of the site.

Since the nineteenth century, street trees have become a significant component of urban landscapes, with multiple ecological roles and social-economic functions. However, data about their abundance and diversity, and information about the criteria used for the species selection, are still limited. Besides providing a historical overview, we analyze and compare data on abundance, diversity and criteria of species selection of street trees in 15 Italian cities chosen considering their representa- tiveness along a bioclimatic transect across Italy. The biodiversity of urban street trees resulted quite rich with 277 species (about 60% are exotic); among these, Platanus × hispanica Mill. ex Münchh., Celtis australis L. and Quercus ilex L. resulted as the most common species. Besides the general suitability for the local climatic conditions, several factors seem to concur in the species selection, such as their aesthetic appeal and dimension. Other selection criteria based on the species’ ecology or functionality were not evident.

The conservation of stone monuments is a constant concern due to their continuous weathering, in which biofouling plays a relevant role. To enhance the effectiveness of biocidal treatments and to avoid environmental issues related to their possible toxicity, this research aims at formulating and characterizing a coating charged with an eco-friendly biocide and showing hydrophobic properties. For this purpose, zosteric sodium salt—a natural biocide product—has been encapsulated into two silica nanocontainers and dispersed into a tetraethoxysilane-based (TEOS) coating also containing TiO2 nanoparticles. The coatings were applied on four different types of stone: brick, mortar, travertine, and Carrara marble. The effectiveness of the coating formulations and their compatibility concerning the properties of coated stones were assessed. The results showed that all coatings conferred a hydrophobic character to the substrate, as demonstrated by the increase of the static contact angle and the reduction in the capillary water absorption coefficient. The transmission of water vapor of the natural stones was preserved as well as their natural aspect. Furthermore, the coatings were homogeneously distributed on the surface and crack-free. Therefore, the protective capability of the coatings was successfully demonstrated.

Multi-temporal investigation of biodeterioration patterns (BPs) in cultural heritage sites is crucial for the development of effective management plans. Here, microscopy and biomolecular methods were employed to analyze the BPs, which took place in the Crypt of the Original Sin (Italy) over a wide temporal scale, i.e., from 2001 to 2017. Before restoration interventions, performed in 2002–2003, a variety of BPs was observed, including green patinas (Chlorophyceae), brown-black patinas (Cyanobacteria), rosy discolorations (Actinobacteria) and some colonization by lichens, mosses and ferns. Restoration included biocide treatments as well as structural interventions causing environmental modifications of the site. To interpret the ecological relationships between environmental factors and temporal changes, we combined the analysis of ecological information on the various BPs with the results of a multivariate statistical analysis. Using BPs as bioindicators, humidity maps of the plasters were generated and water infiltration paths reconstructed. Several years after biocide application, a significant reduction of BPs was observed, together with limited colonization by dematiaceous and meristematic fungi. Our observations demonstrate the usefulness of combining structural and environmental interventions for an effective restoration strategy; these interventions reduced the moisture levels of the walls, consequently reducing biological colonization. Moreover, our findings suggest that monitoring BPs during time can be of guidance in the long-term maintenance of cultural heritage, and provide an evidence-based model for preventive interventions and biocide treatments.

bstract Purpose The colonisation of building material by photosynthetic organisms is highly dependent on the environmental conditions and the nature of the substrate. The growths of red-orange phototrophic biofilms have been widely reported in the literature and have commonly been associated with the order Trentepohliales, whose ecological and taxonomical information needs to be improved. Considering the recurrent presence of such biofilms throughout the Lazio region, we would identify the occurring species and define their favourable environmental conditions, through morphological, genetic and ecological analyses. Results Biofilms were collected across an altitude range of 0 to 860 m asl, occurring from the coast to 60-km inland. A dominant presence of the filamentous terrestrial green alga Trentepohlia umbrina (Kützing) Bornet was confirmed in all sites sometimes mixed with cyanobacteria of the genus Gloeocapsa. The distribution of Trentepohliales is generally given as pan-tropical, but some species, such as T. umbrina, are also distributed in temperate climates. Here, it is reported for the first time a Mediterranean occurrence of the species. Low humidity and light conditions, such as those occurring on vertical surfaces with mainly northern aspects, are the preferred environmental conditions. Coastal areas were more favourable for its growth, probably due to the higher nocturnal condensation that occurs here. Concrete and mortars were particularly bioreceptive to T. umbrina, but marble and trachyte were also colonised under favourable conditions. Conclusions The findings better define the ecological range of this species, suggesting a wider biogeographic distribution, and adding information on morphological features and genetic data.

The conservation of underground tombs is affected by several physical-chemical and biological factors, which could be reduced by insulating systems able to maintain the microclimatic stability also decreasing the biodeterioration risk. In Mediterranean areas, wild ephemeral plants, which reduce their cover during the hot season, seem unsuitable for reducing summer overheating. In this study, we wish to assess the influence of vegetation cover and of overlaying soil, after the establishment of an evergreen turf of a cultivar of Cynodon dactylon, on two tombs in the Etruscan Necropolis of Monterozzi, covered by linear-shaped tumuli. Therefore, we evaluated for 10 months the thermo-hygrometric values of these tombs, together with two tombs as controls. We also evaluated the different tumuli’s morphologies and the related received solar radiation. Results confirmed that late summer and early autumn as critical microclimatic periods for the risk factors of hypogeal paintings when peaks of superficial temperature occur. A positive influence of vegetation cover on maintaining constant humidity and internal temperatures was detected, but the mounds orientation, as well as soil depth, seems to have a relevant role. Considering the naturalistic features of the area and the related cultural ecosystem services, a careful selection of wild plants is suggested.

The hypogeal cultural heritage due to their favourable environmental conditions can be subject to microbial attack usually controlled using biocides. Recently the number of products allowed in the restoration practice has been reduced because, in addition to their effectiveness, the biocidal product should not have effects on the treated surfaces, and it should be safe for the operator and environment. Following this field research, we propose a reconstruction experiment in which we tested 4 different natural products (Clove oil, Oregano Oil, Usnic Acid, IPA+ DMSO + Usnic Acid) on tiles, reproducing the substrate of Etruscan hypogeal tombs (Macco) of Monterozzi Necropolis, inoculated with a selection of fungal/bacterial strains. After one month from the biocide’s application, we evaluated their efficiency by image analysis and by culture analysis. The achieved results evidenced a clear gradient between the four tested biocides and gave suggestions for further improvements.

The high humidity characterizing subterranean environments promotes biological growth, de- spite their low irradiance and oligotrophy. Microbial metabolism can have a negative impact on cultural heritage artworks, necessitating the use of effective biocides to control them. Among biodeteriogens, fungi are particularly difficult to manage due to their diverse metabolic pat- terns and high dissemination rate. In a recent study performed on two painted Etruscan tombs in Tarquinia some dark discolorations were investigated to determine the possible causative agents of color changes, and tomb door seals were investigated as a possible route of contam- ination. Among the widest culturable fraction found we focused on eighteen dark-pigmented fungi. Assessing their metabolic skills and tolerance to two formulations of benzalkonium chlo- ride-based products revealed a risk for hypogea that extends far beyond their color.

Street trees are key elements in urban ecosystems from several points of view, and different species can have different functions (i.e., ecological, socio-economic). As such, a careful biodiversity assessment is pivotal. We evaluated urban street trees in 15 Italian cities along a geographical and bioclimatic gradient. The data was obtained from scientific literature and Garden Service Offices of the cities. The distribution patterns of the species were analyzed in terms of taxonomy, chorology, and tree size. We registered 277 tree species belonging to 48 families. The species richness is very variable in analyzed cities, and it is not directly correlated with the city’s size. Only three species (Platanus × hispanica, Celtis australis and Quercus ilex) are common to almost all cities, while 41.52% of the species are present only in one city. The comparative analysis of species, considering the floristic and city distribution, showed different results, highlighting Pinaceae as the most common family. The chorological analysis shows a predominance of exotic species and a good relationship with the bioclimatic conditions of cities. A selection of the species, as street trees to maximize their ecological and socio-economic functions, is pivotal in urban landscaping and green management.

In cultural heritage field, significant research efforts have been recently made to improve the efficacy of anti-vegetative treatments and to reduce the environmental impact caused by biocides high concentration. According to the pro-ecological approach, this work reports a novel approach based on the encapsulation/incorporation of environmentally-friendly biocides in different silica nanosystems in order to control the development of biological patinas on outdoor cultural heritage. Two different green biocides have been selected and tested in silica nanosystems: the zosteric acid sodium salt (ZS), a natural antifoulant compound produced by Zostera marina (eelgrass), and the usnic acid (UA), a secondary metabolite produced by some saxicolous lichens. ZS was previously successfully encapsulated but never entrapped in mesoporous silica; instead, UA is, for the first time, encapsulated and in situ entrapped into the silica nanosystems in order to control the release over time. Both silica nanosystems have been characterized as far as their dimensions and superficial properties and loading capability. The antifouling activity was assessed against microorganisms from biopatinas colonising the Aurelian Walls in Rome. Our results have shown that the two nanosystems have complementary properties, thus it is possible to tune the antifouling efficiency by combining the two in different proportions.

According to projects and practices that the Italian botanists and ecologists are carrying out for bringing “more nature in the city”, new insights for a factual integration between ecological perspectives and more consolidated aesthetic and agronomic approaches to the sustainable planning and management of urban green areas are provided.

The use of symbols in architecture of the past centuries is evident, even if sometimes cryptic. The reasons behind the representation of plants in artistic and architectural contexts are of great interest as they help in their understanding. We analysed the plants carved in the Fountain of Four Rivers (Rome), designed by G.L. Bernini (mid-seventeenth century), through iconographic and historical documents. The carved plants (about 34 species) creates a natural and symbolic association with the selected rivers and continents. Some species are chosen to characterise various geographic contexts or fluvial and rupestrian habitats or are referred to the papal coats of arms (Innocent X Pamphilj). A certain number has auspicious connotation and takes a strong symbolic salvific meaning and protective against the evil’s threat. The Kircherian influence emerges in several iconographic choices, as well as the river selection and orientation, in a philosophical-religious logic linked to the Papacy and Christianity role.

The Mediterranean basin has been a refugium for relict plant taxa and native laurophyllic forests. The Latium coasts and, especially, the Antica Lavinium site, host relict forest communities, whose natural importance is enriched by their cultural value. Here, we aim at investigating the ecological framework, cultural and historical values, and management over time, of relict communities that have Laurus nobilis and Celtis australis as their priority habitats. To achieve this, we performed vegetation surveys and we conducted statistical analyses (PCA, NMDS). Among the 45 vegetation surveys, 25 were characterized by the two target species. The PCA analysis highlighted how the L. nobilis formations and the mixed formations with C. australis present some differences but are not sufficient to describe different coenosis. The comparison among similar forests in central and southern Italy confirmed the wide coenological amplitude of L. nobilis with respect to other laurophyllic species. Antica Lavinium has an overall good preservation of laurel forest formations, but also of mixed formation with C. australis. In the area, historical, cultural, and natural characteristics mutually contributed to the development of human civilizations and plant communities, highlighting their deep linkage.

In the last decade, worldwide research has focused on innovative natural biocides and the development of organic and inorganic nanomaterials for long-lasting reliability. In this work, the biocide effects of two different biocides encapsulated in two different silica nanosystems for a multifunctional coating have been performed through in vitro tests, by using Chlorococcum sp. as a common stone biodeteriogen. Zosteric sodium salt (ZS), a green biocide, was compared with the commercial biocide, 2-mercaptobenzothiazole (MBT), widely used in the treatment of cultural heritage. The analyzed systems are the following: silica nanocapsules (NC) and silica nanoparticles (MNP) not loaded with biocides, two nanosystems loaded with ZS and MBT, and free biocides. The qualitative and quantitative evaluations of biocide efficiency were performed periodically, analyzing pigment autofluorescence to discriminate between active and inactive/dead cells. The analyses showed multiple differences. All the nanocontainers presented an initial reduction in chlorophyll’s autofluorescence. For the free biocide, the results highlighted higher efficiency for MBT than ZS. Finally, the nanosystems loaded with the different biocides highlighted a higher activity for nanocontainers loaded with the commercial biocide than the green product, and better efficiency for MNP in comparison with NC.

A study was carried out on biodeterioration processes at six Jewish cemeteries in north-eastern Italy, which were generally subject to very poor maintenance. Several crustose lichens, as well as ruderal wooden plants, were found growing differentially on stone types in the various cemeteries. Lichens colonizing gravestones and woody plants were examined through field observations and several microscopic analyses. Evaluations were carried out on selected species and some damage risk indices were applied. The Index of Lichen Potential Biodeteriogenic Activity (LPBA) was calculated for Nanto stone, which suffered the highest degree of deterioration. The Hazard Index (HI), which is independent from the lithotype, was calculated for all the wooden plants. We also analyzed the ecological relationships of such colonization in order to evaluate indirect conservation treatments. The various lichen species were causing differential interactions with the stone, sometimes contributing in cracking and detachment of fragments. Their potential aggressiveness is mainly attributable to the different lithotypes, but also to changes in maintenance, tree canopy cover, and eutrophication. We have made suggestions for an appropriate plant management that considers their environmental, ornamental and symbolic importance in such context. For the stone conservative treatments against lichens, we also carried out tests on selected biocides.

When the Local Cuisine Still Incorporates Wild Food Plants: The Unknown Traditions of the Monti Picentini Regional Park (Southern Italy). Wild food plants are still part of the culinary traditions of many rural areas in the Mediterranean. This study aims to document these traditions and the food uses of wild plants in an area of the Monti Picentini Regional Park. We performed an ethnobotanical survey between 2013 and 2015 using standard ethnographic methods. We analyzed the gathered data using ethnobotanical indices, and we compared our results with relevant literature pertaining to uses of wild food plants in Central and Southern Italy. We interviewed 64 key informants, whose ages ranged between 40 and 93 years, and we gathered about 1900 use citations about the traditional food uses of 84 wild plant species. Many of these species are still incorporated into traditional dishes. We recorded the previously unknown food use of four plant species (Rubus hirtus Waldst. & Kit.; Petasites hybridus [L.] G. Gaertn., B. Mey. & Scherb.; Asphodelus macrocarpus Parl.; and Oenanthe fistulosa L.). We also highlighted several rare food uses as well as many other uses that are common across Central and Southern Italy. Knowledge concerning the uses of wild food plants is part of Italy’s history and culture, and it should be preserved before modernization of lifestyles and homogenization of food habits extinguish this realm of food and culinary knowledge.

Vegetation management of archaeological sites is a recurrent problem when considering the conservation of historic structures and biodiversity. In the UNESCO site of the Etruscan necropolis “La Banditaccia” (Cerveteri, Italy), several plants grow on the ancient tumuli, which are subjected to different management practices. In order to assess the influence of interventions on plant colonisation, a comparative analysis of several tumuli was performed, through structural, chorological, phytosociological and statistical evaluations. This investigation identified and defined an ecological gradient among the tumuli. The cover values of Therophytes and Hemicryptophytes decreased by half with regular cutting, while those of Geophytes and Phanerophytes increased. Mesophilic field plants (MFP), both ephemeral and perennial, represented the most abundant group. Mediterranean bushes and forests (MBF) showed a positive trend from the entrance to the last tumuli of the necropolis. This trend was clearly defined by PCA, and it seems community changes were caused by the absence of mowing activities and to a lower tourist frequentation. SIMPER analysis highlighted which species on each tumulus mainly influence their dissimilarity. This knowledge, when combined with the evaluation of the potential risk of the different plant communities growing on the tumuli, can help to identify the best management practices.

Green roofs provide a number of environmental advantages like increasing urban biodiversity, reducing pollution, easing burdens on drainage systems, and lowering energy costs thanks to thermal insulation. Frankenia laevis, Dymondia margaretae and Iris lutescens were tested in a green roof installation. For all three species, we assessed two minimal irrigation treatments and one rain-fed treatment to resemble Mediterranean climate conditions analyzing the thermal and hydrological performance of all three species and their substrates through an evaluation of green cover, mortality, and biomass. The most influential factors registered for all three species are the relationship between air and water in the substrate and the interaction between green cover and substrate, respectively, for summer and winter seasons. In particular, D. margaretae preserved more water in its substrate than the other species both in summer and winter and after each rainfall event. F. laevis registered the highest level of variation in terms of substrate water content and of rainwater retention. I. lutescens achieved low hydrological performance, a limited amount of green cover, and slow growth. Our results suggest the absolute need of additional irrigation, managed in accordance with specific functional objectives, for all three species analyzed under Mediterranean conditions and different water regime info:eu-repo/semantics/publishedVersion

In April 2016, William Kentridge realized the bio-artwork “Triumphs and Laments” along the Tiber embankments, representing a figures procession, chosen as relevant steps of Roman history. The drawing rose in negative after applying a stencil onto the homogeneous black biopatinas and removing them through a low-pressure washer. The patinas, growing on the travertine surfaces, were dominated by cyanobacteria communities, mainly composed by Chroococcus lithophilus, Myxosarcina spectabilis, Tolypothrix byssoidea, and Synechocistis pevalekii. To collect precise data on the dynamic of biological recolonization, we monitored the figure's life by 2016–2020, analyzing the progressive darkening, which gave rise to the artwork disappearance. By image analysis and color variation values (ΔE), using a detailed photographic survey (every 3–4 months) and colorimetric sampling (once in the year), we assessed the recolonization phenomena and their seasonal dynamics. A progressive relevant increase of black intensity started from the 3rd year and usually 4–5 years were sufficient for a complete recolonization. We also collected climatic data and performed elaborations on Cold and Drought Stress, which provided evident correlation among biological colonization and climatic data, with their seasonal fluctuations. When a longer duration of such bio-artwork would be required, such information will be useful in suggesting treatments.

Community gardening is a current global phenomenon and the general purposes of these horticultural areas in cities are to provide food but also for food security needs. Other ecosystem services, such as improving people’s quality of life, the urban environment and social relations, are also often underlined. Despite the increasing phenomenon of urban community gardens, planning guidelines concerning specific objectives are still needed. Literature underlines five principal aims in setting up urban community gardening, and we suggest “Cultural values” as an additional one. Moreover, we propose a set of 12 basic indicators to support the best choice for the six aims. We also discuss the importance of these indicators which come within three broad categories: A) environmental parameters: morphology, soil, sunlight, water supply, biodiversity value; B) risk factors due to urban pollution, which needs to be investigated further: local pollution linked to urban traffic, local pollution derived from previous activities on the site; C) accessibility and social context: accessibility, schools, community centres, green areas. Since each parameter has a different influence in relation to the various identified aims, we suggest their relative weights, which have to be considered in the different cases, and their needed minimum values. Last of all, we apply the proposed evaluation criteria in several municipal areas of Rome. Our data show that these indicators can easily be applied in selecting the best solutions for this type of urban planning.

The weathering role of Wind-Driven Rain (WDR) on buildings is widely recognised from a physical point of view, but the influence of WDR on Biological Growth (BG) on stone materials to cause biodeterioration is still not well studied. Following our previous results from the Roman area, the UNESCO site of Pompeii for its importance was selected to further test relationships between WDR and BG. We collated and analysed climatic data (rainfall, direction and intensity of winds) between 2010 and 2015 to delineate the thermo-pluvial diagram and extrapolate Dominant Winds (DW) and WDR. Data on BG, consisting mainly of cyanobacteria, algae and lichens, were also collected through sampling, direct observations and analysis of high-quality photos. The climatic elaborations highlighted a dominance of the West wind influencing WDR. The BG was more prominent on the northern and western exposures, while it was considerably less extensive on the southern walls. Our results also showed that water from WDR, together with the lower temperature in the northern exposure and poor ventilation, can all affect wetness and had a profound role in the promotion of BG. Our analyses suggest that the protection of building walls should be different according to the exposure conditions in the formulation of preventive strategies for conservation.

The archaeological site of Herculaneum (Campania, Italy), which was buried as a result of the eruption of Mt. Vesuvius in the first Century C.E., was first excavated in the XVIII century. It has been included on the UNESCO World Heritage List since 1997, and in 2001 the Herculaneum Conservation Project (HCP) was started, which has carried out, among other activities, studies and conservation interventions across the site. Up until this time, little data has been available on the growth of biological agents that could cause biodeterioration of wall paintings and archaeological structures. Particularly, the presence of rosy discoloration is frequent on ancient monuments of the Vesuvian area, even if such phenomenon has so far been largely neglected. In this study, we describe, for the first time, the pink patina distribution and the microbial species isolated from the House of the Bicentenary in Herculaneum. By combining culture-based approaches with molecular and phylogenetic analyses we reliably isolated the pink-producing bacterial species and attributed them primarily to Arthrobacter agilis, and secondarily to Rhodococcus corynebacterioides, and Methylobacterium extorquens. Strains closely related to Dietzia maris and Gordonia rubripertincta were also isolated. With the exception of M. extorquens, a proteobacterium, all of the other isolates belong to the phylum Actinobacteria. All isolates produced carotenoid pigments, suggesting that they can participate in the development of such peculiar coloration. Our data indicate the presence of a large number of pink-pigmented bacterial species in the community, even if the presence of bacteria in viable but not-culturable state, such as Rubrobacter radiotolerans, is not excludible. The culture-based approach had the advantage of (i) obtaining bacterial isolates, (ii) showing their differential ability to produce pink discolorations, and (iii) testing conditions for in vitro growth. Moreover, field observations showed an association of pink patinas with dry conditions, saline efflorescence and moderate solar radiation. Some seasonal variations were also detected, with an increase in late spring and summer.

Archaeological sites can represent a refuge for plant and animal species, protecting them from the pressures of urbanisation. However, sometimes these environmental resources can lead to negative consequences for the monuments. In order to investigate such contrasting effects, we selected the UNESCO World Heritage Site Etruscan necropolis known as “La Banditaccia” (Cerveteri, Italy). We performed floristic and phytosociological analyses, and observations on roots interactions with monuments on several tombs (9 tumuli and 5 cube-shaped tombs) and applied commonly used indices to evaluate damages to the structures. The study revealed rich biodiversity of the site and the presence of rare plants, but also of some invasive species. The analysis of the phytosociological sets showed differences among vegetation types found on the tumuli as a function of the varying degrees of anthropization. Abundant plant colonisation was detected on the top of the tumuli, sometimes causing damages to the structures. The results of the Impact Index analysis showed that the dynamic evolution of vegetation constitutes a significant risk to the archaeological structures. We suggest that careful management of vegetation should achieve equilibrium between the management requirements for the monuments and conservation of naturalistic values. A deeper evaluation of the interactions between plants and monuments is however necessary.

The Uzumlu Church is an unusual soft tuff formation located in central Turkey (Cappadocia) dated around the 7th century. The rocks on its external surfaces show a severe erosion with an evident surface detachment. Moreover, the widely distributed black-grey crusts mainly consisting of lichens point out the need of evaluating their deteriorative effects. This research was focused on lichen deterioration by indicating the biodeterioration processes and on selecting the most appropriate preservation treatments suitable for stone conservation. The interaction of lichens with stone was studied by evaluating through microscopic analyses, the spread and the depth of fungal hyphae penetration, and by applying the LPBA Index. The SEM analysis of all fragments shows a dramatic loss of the stone matrix and a dense network of fungal hyphae within the rock. Nevertheless, both the high penetration of fungal hyphae, and the consequent difficulty in their removal without a strong peeling effect, both the relevant loss of the stone matrix and finally the evident reduction of water penetration when crusts are present in the surfaces, advise against their removal. Further chemical treatments of consolidation should be carefully evaluated.

In this study, we support the hypothesis that wall plant species come mainly from rocky habitats, taking into account that ancient walls show similar characteristics to rocks. The occurrence of wall species in natural habitats was investigated. The main literature concerning wall and natural vegetation of central-southern Italy was viewed. Vegetation synoptic tables were analysed through statistical procedures for comparing occurrence and behaviour of wall species in ruderal habitats as archaeological sites and natural ones.The study pointed out that wall species show similar ecological and coenological features in both habitats. This confirms that the main natural habitat from which wall species come from are rocks, but secondarily also ephemeral Mediterranean meadows and garrigues. Particularly, some wall species belonging to Parietarietea judaicae class are participating in the formation of natural rocky communities of Asplenietea trichomanis. Species occurring on emerging ruins form ephemeral meadows belonging to Helianthemetea guttati, also found in natural Mediterranean environment. On wide tops of ruins, where community dynamism is higher, some perennial herbaceous and shrubby species participate in the formation of impoverished communities matching to natural aspects of Mediterranean maquis. The knowledge of the natural habitat of wall species can be useful for a better management of archaeological sites.

Ivy (Hedera helix L.) growing on monuments is a common issue in the study of nature’s relationship with artefacts in the Euro-Mediterranean area. This is due to its pervasiveness and its double role as protective and as deteriogen. We studied the effect of ivy colonization within the archaeological site of Villa of Massentius. We applied a quantitative method derived from monument mapping method by Fitzner, to evaluate deterioration due to ivy colonization on vertical surfaces. Instead, the capping ivy effects was investigated through a multi-parameter evaluation. We recognized three different damage categories: the superficial loss of surface (W), ivy residues on wall after the removal event (I), and the loss of compact stone fragments (P/O). Mean W corresponded to 58% and P/O to 14%. The total damage rate was positively correlated to the amount of ivy cover and to favourable shady conditions. For the capping ivy, we calculated an average loss of 4.34 cm3/m2 and a high level of soil deposit, which led to a secondary ivy colonization process. This paper proposes a contribution to the identification and quantification of ivy deteriogen activity. The application of the proposed method also provides a useful tool for planning restoration activity.

Various biological communities colonize the Khmer temples in Angkor (Cambodia), which had lain abandoned for many centuries. These biodeterioration patterns change in response to different environmental conditions, and the aim of this study is to quantify their frequency and ecological characteristics according to a forest canopy gradient. The descriptive and multivariate statistical analysis applied to data collected from the four temples in the study identifies various biological communities along with a temple-specific ecological succession. The initial pioneer community is primarily composed of a reddish biofilm of the green alga Trentepohlia sp., and it occurs in xeric and shady environmental conditions, becoming dominant in forested areas. Cyanobacteria biofilm, consisting of species belonging to the genera Scytonema and Gloeocapsa , sometimes in combination with the lichen Endocarpon sp., prevails in xeric and sunny conditions. With the progressive increase of the availability of edaphic water, typical of forested areas, various lichen communities are able to establish themselves (dominated by Lepraria , Pyxine coralligera and Cryptothecia subnidulans respectively), followed by moss and higher plant communities. Understanding these relationships appears to be a very useful way of identifying the best microclimatic conditions for stone conservation.

The biological colonization present on the temples of the UNESCO World Heritage site of Angkor is wide and relevant, but a debate on its biodeteriorative and bioprotective effects is now developing. We investigated the biological patterns observed on two temples (Ta Nei and Ta Keo) exposed to different microclimatic conditions, in order to assess the damage caused by the communities present on the stone. We analyzed the penetration (depth and spread) into the stone, and the degree of decohesion of seven communities (green algae, cyanobacteria, lichens and mosses). The microscopic analyses highlighted a clear interaction between organism and stone, displaying a trend of increasing harmfulness from the community of the green algae (Trentepohlia) up to the moss communities. All the lichen communities show biodeterioration abilities: the Pyxine community seems more aggressive than the Lepraria and Cryptothecia communities, and more also than the cyanobacterial communities. The positive effects of the lichen cover in reducing dangerous evaporation processes cannot outweigh the negative effects of their hyphal penetration. Light forest cover seems beneficial for the conservation of the Angkor monuments since it reduces evaporation processes, but further studies should be carried out so as to find an optimal balance between contrasting factors.

Poly(ethylene terephthalate) (PET) / poly(ethylene) (PE) granules coming from a post-industrial packaging stream were directed to new applications. The collected material was first characterized through selective extractions followed by infrared analysis. After the characterization work the presence of poly(ethylene-co-vinyl acetate) (EVA) copolymer was evidenced. Moreover the degree of yellowing was shown to increase by increasing the PE content in the granules batch. The blending of PET/PE with a stabilizer allowed to control its thermal stability, moreover the addition of compatibilizers resulted in the possibility of modulating both rheological and mechanical properties. Hence the use of stabilizers and compatibilizers allowed to upgrade postindustrial PET/PE based materials for the use in different industrial applications

[EN] One promising way to improve the efficiency of borehole heat exchangers (BHEs) in shallow geothermal applications is to enhance the thermal properties of the materials involved in its construction. Early attempts, such as using metal tubes in the 1980s or the utilization of thin-foil hoses, did not succeed in being adopted by the market for diverse reasons (cost, corrosion, fragility, etc...). In parallel, the optimization of pipe size, the use of double-U-tubes, thermally enhanced grout, etc. were able to bring the measure for the BHE efficiency, the borehole thermal resistance, from 0.20 to 0.15 K/(Wm) down to 0.08-0.06 K/(Wm) in the best solutions today. A further improvement cannot be expected without development of new, dedicated materials, combining the versatility of plastic like PE with an increased thermal conductivity that matches the respective properties of the rock and soil. This goal was included in the Strategic Research and Innovation Agenda of the European Technology Platform on Renewable Heating and Cooling in 2013. Within an EU supported project, both BHE pipes and grouting materials have been produced prototypically in small amounts, suitable for the first tests in the intended environment. The present work explains the research pathways envisaged and the resulting sensitivity analysis to highlight the influence of some of the most critical parameters that affect the overall performance of a GSHP system. The results have allowed guiding the real development of more efficient new advanced materials for different scenarios representative of different European regions. Finally the developed materials and their properties are discussed, including a comparative assessment about their compliance with reference material properties as currently seen in the BHE market., This article is part of a project that has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 727583.