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Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record covering the past ~ 8,000 years from Lago di Baratz, north-west Sardinia. Vegetation and fire history are reconstructed by pollen, spores, macrofossils and charcoal analyses and environmental dynamics by high-resolution element geochemistry together with pigment analyses. During the period 8,100–7,500 cal bp, when seasonality was high and fire and erosion were frequent, Erica arborea and E. scoparia woodlands dominated the coastal landscape. Subsequently, between 7,500 and 5,500 cal bp, seasonality gradually declined and thermo-mediterranean woodlands with Pistacia and Quercus ilex partially replaced Erica communities under diminished incidence of fire. After 5,500 cal bp, evergreen oak forests expanded markedly, erosion declined and lake levels increased, likely in response to increasing (summer) moisture availability. Increased anthropogenic fire disturbance triggered shrubland expansions (e.g. Tamarix and Pistacia) around 5,000–4,500 cal bp. Subsequently around 4,000–3,500 cal bp evergreen oak-olive forests expanded massively when fire activity declined and lake productivity and anoxia reached Holocene maxima. Land-use activities during the past 4,000 years (since the Bronze Age) gradually disrupted coastal forests, but relict stands persisted under rather stable environmental conditions until ca. 200 cal bp, when agricultural activities intensified and Pinus and Eucalyptus were planted to stabilize the sand dunes. Pervasive prehistoric land-use activities since at least the Bronze Age Nuraghi period included the cultivation of Prunus, Olea europaea and Juglans regia after 3,500–3,300 cal bp, and Quercus suber after 2,500 cal bp. We conclude that restoring less flammable native Q. ilex and O. europaea forest communities would markedly reduce fire risk and erodibility compared to recent forest plantations with flammable non-native trees (e.g. Pinus, Eucalyptus) and xerophytic shrubland (e.g. Cistus, Erica). [ABSTRACT FROM AUTHOR]

A non-invasive characterization study has been performed and here presented for the first time on the masonry altar of S. Maria ad Undas, a parish medieval church on the Idro (Brescia, Italy) lakeshore. The determination of painting materials and of alteration products represent the one of the first steps, together with art history studies, of a wider project aimed to the valorization of the site. Images collected under UV light in fluorescence and reflectance mode provided useful information about the presence of organic residual materials attributable to the application of lost gilding details, while the readability of some particulars was greatly improved with respect to what observable in visible light. Moreover, near infrared (NIR) images led to hypothesize the presence of green earths in green painted areas. Raman and reflectance spectroscopy allowed the identification of the pigments and of several alteration products, such as plattnerite, which derived by the degradation of the lead-based ones, hydromagnesite, gypsum, and niter, as well as of carbon-based depositions. [ABSTRACT FROM AUTHOR]

Chronological and stylistic studies of Roman wall paintings and mosaics were based for a long time only on optical direct analysis and current analogue or digital photographic reproduction. The aims of fresco research today remain the same as in the past — i.e. pigment types and sources, painting subjects and styles, application methods, and the relationship between paintings and the function of their locations. Modern technologies, however, have now been developed which can finally improve our knowledge about ancient decorative taste and workshops. New methodologies such as highly accurate colour reproduction of paintings and mosaics, digital reconstruction of fragmentary decorations, or chemical analyses of pigments or plasters are increasingly being used to fill important research gaps. Some of these techniques are illustrated in this article as solutions to obstacles in the archaeological documentation of an unpublished first-century ad painting (Late Flavian period) on the Caelian Hill in Rome. With relation to Fourth Style decorations, the problematic question as to whether there was an intentional ratio between the component parts of the fresco is also discussed, linking for the first time the Vitruvian architectural concept of Commodulatio (meaning ‘with symmetry/proportion’) to wall paintings. [ABSTRACT FROM PUBLISHER]