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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.

Due to the specific microclimatic conditions, mural paintings placed in hypogean monuments occur to biological attack. The application of natural biocides, safe and eco-friendly, is the bet- ter solution to prevent biodeterioration phenomena in this context. Lately, many new green biocides have been developed but applied in the conservative intervention only to a minor ex- tent; because of the fewer data about the interaction of the new products with the substrate. This study aimed to investigate the interference test of four green biocides on mural painting in Etruscan tombs (Necropolis of Monterozzi, Tarquinia). Mock-ups of Etruscan mural painting were reproduced and tested in similar hypogean microclimatic conditions. Colorimeter, contact sponge method and portable optical microscope were applied.

il pino domestico è il vero simbolo di albero italico. Non a caso gli inglesi lo chiamano Italian stone pine e in Francia Pin d’Italie. È l’albero di casa nostra perché il paesaggio mediterraneo non è umile né dimesso. È grandioso, solenne, rifiuta la pompa dei colori esotici tropicali. Il pino, questo grande e maestoso albero, dall’odore penetrante, caratterizza, fino a diventarne l’icona, la macchia mediterranea dei litorali tirrenici, adriatici e ionici e delle isole di Sardegna e di Sicilia.

Scientific culture is part of our culture, our origins and roots, and cultural heritage allows awareness of how much we are immersed in scientific knowledge. Rome is a rich natural and historical laboratory where we have proposed on-field activities to transmit scientific culture to primary and high schools. The multidisciplinary project From cosmos to the earth, to life, to culture. A resilient strategy for the dissemination of natural, physical and mathematical sciences: a proposal for a diffused museum for the city of Rome (Principal Investigator Prof. Settimio Mobilio) was written by the Departments of Architecture, of Mathematics and Physics and of Science of Roma Tre University, and was funded by the Italian Ministry of Education in 2016. It involves Architecture, Physics, Botany, Geology, and Mathematics. Digital resources cannot replace on-field experience, especially as scientific approach. Our motto is “The earth beneath your feet, the sky above your head, architecture on the premises”. The languages of art and science cooperate to tell to school audiences about the geological features of the center of Rome and the ornamental stones of medieval Basilicas; about the richness of the natural elements of the imperial Ara Pacis of Augustus, both decorative, and symbolic-allegorical, and finally about the extraordinary botanical biodiversity that converged in Rome from all over the world, and changed along history with geographical discoveries, illustrated in the festoons of the Renaissance Loggia di Amore e Psiche. Astronomy in the educational Astrogarden of Roma Tre unusually links myths and direct observations. URL, http://museodiffuso.uniroma3.it/index.php/it/

This contribution updates the methodological approach currently applied in Europe for interventions in the field of stone conservation. Firstly, we describe the advancements in physical methods, which encompasses several already tested methods, such as Ultravi- olet rays and Laser cleaning, and new ones, such as Ice cleaning systems, Microwaves, and Heat shock treatments. Specifically, we discuss the efficacy of Heat shock treatments, which is an innovative and eco-friendly method, indicated their suitability especially against lichens and mosses colonization in wet conditions. Secondly, we describe the ad- vancements in the selection and use of biocides, which considers overall Natural biocides, such “green and blue” biocides, produced from plants or marine organisms. These biocides are safer compared to the traditional chemical ones, and that gave interesting results as regards efficacy for target species. We also provide comments about other chemical com- pounds, such as Multifunctional biocides with Self-cleaning properties, using primarily titanium dioxide. Among new products and techniques, we highlight functionalized Nano- materials, which have more pronounced characteristics compared to the same materialwithout nanoscale features, and seem to be a new challenging type of chemicals whose application is growing. The Bio-cleaning with microorganisms, such as the Cleaning of bi- ological patinas with enzymes and solvents, is also receiving attention and is getting more and more used. Long-lasting interventions with paired treatments, such Consolidants or Water-repellent products and biocides, also seem promising. Pigments, polysaccharide in- hibitors and permeabilizers with biocides, gave interesting results in the laboratory, even if the advantages of such treatments need further evaluation. Finally, for a management plan of archaeological areas or monumental sites, we underline the importance of preventive conservation strategies, and the need of further research, especially to define the ecological limits of the different biological colonizations.

In the archaeological Khmer complex (Cambodia), an unusual black patina covering both the exterior and interior walls of the Neang Khmau temple, has been observed during a recent conservative survey. In fact, it is present over all the four facades of the temple, covers a relevant part of the vertical surfaces protected from rainfall and is also homogeneously distributed on the interior of the monument. The upper and the lower areas show, on the contrary, a relevant lichen growth. The temple was built by using laterite bricks, a natural material common in tropical areas as a weathering product of pre-existing rocks. A preliminary investigation on the patina samples together with ecological considerations excluded a biological origin of the black alteration, thus prompting a more detailed study. In this work, we have investigated the physico-chemical origin of this unusual patina by identifying its mineralogical and chemical composition. Raman and FTIR spectroscopies, SEM-EDS, micro-XRF and XRPD have been applied to characterize the alteration products. Analyses have been performed both on single fragments and on polished cross sections collected from all four temple facades and from one area in the temple interior. Optical observations of the cross sections have evidenced irregularities in the thickness of the patina. Raman and FTIR spectra have revealed that the black layers are mainly composed of manganese minerals (hollandite, romanechite and manganite). This peculiar alteration pattern is interpreted as because of the tropical climatic conditions of Cambodia. Indeed the variation of wet and dry seasons favours the migration of iron and manganese ions and their successive immobilization in regions not directly subject to leaching.

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