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Although coppice forests represent a significant part of the European forest area, especially across southern Countries, they received little attention within the Sustainable Forest Management (SFM) processes and scenarios, whose guidelines have been mainly designed to high forests and national scale. In order to obtain “tailored” information on the degree of sustainability of coppices on the scale of the stand, we evaluated (i) whether the main coppice management options result in different responses of the SFM indicators, and (ii) the degree to which the considered SFM indicators were appropriate in their application at stand level. The study considered three different management options (Traditional Coppice TC, coppice under Natural Evolution NE, and coppice under Conversion to high forest by means of periodical thinning CO). In each of the 43 plots considered in the study, which covered three different European Forest Types, we applied a set of eighteen “consolidated” SFM indicators, covering all the six SFM Criteria (FOREST EUROPE, 2020) and, additionally, tested other sixteen novel indicators shaped for agamic forests and/or applicable at stand level. Results confirmed that several consolidated indicators related to resources status (Growing stock and Carbon stock), health (Defoliation and Forest damage), and socio-economic functions (Net revenue, Energy and Accessibility) were highly appropriate for evaluating the sustainability of coppice at stand level. In addition, some novel indicators related to resources status (Total above ground tree biomass), health (Stand growth) and protective functions (Overstorey cover and Understorey cover) proved to be highly appropriate and able to support the information obtained by the consolidated ones. As a consequence, a subset of consolidated SFM indicators, complemented with the most appropriate novel ones, may represent a valid option to support the evaluation of coppice sustainability at stand level. An integrated analysis of the SFM indicators showed that NE and CO display significant higher environmental performances as compared with TC. In addition, CO has positive effects also on socio-economic issues, while TC -which is an important cultural heritage and a silvicultural option that may help to keep local communities engaged in forestry – combines high wood harvesting rates with dense understory cover. Overall, each of the three management options showed specific sustainability values; as a consequence, their coexistence at a local scale and in accordance with the specific environmental conditions and the social-economic context, is greatly recommended since it may fulfill a wider array of sustainability issues.

The effects of reduced nitrogen compounds on epiphytic lichen vegetation have been largely investigated in northern Europe. This paper reports for the first time results of a study carried out on pine trees in the Mediterranean basin. Contrary to the usual acidophytic lichen colonization of pine bark, in this case a nitrophytic lichen vegetation was found, suggesting that the study area is characterized by a diffuse eutrophication. Tree circumference, distance from the stock farms, bark pH and bark electrical conductivity emerged as the main factors influencing the distribution and abundance of epiphytic lichens in the study area. Both Hyperphyscia adglutinata and Xanthoria parietina were suitable local indicator species of high pine bark pH values. However, while X. parietina indicated high nitrogen dust pollution, H. adglutinata occurred also where there was an additional increase in bark pH caused by the release of high amounts of ammonia. The increased nitrogen availability caused by ammonium apparently had no effect on the occurrence of nitrophytes.

The results of long-term biomonitoring of nine elements (Cd, Cr, Ni, Pb, V, Cu, Zn, Fe and Al) with the epiphytic lichen Xanthoria parietina over a seven year time span are reported. A total of 51 sampling stations were monitored in two surveys, obtaining information about heavy metal concentrations in a large area characterized by a high impact of industrial and urban sources of air pollution. The results showed that the approach adopted is indeed a reliable tool to assess environmental alteration, pinpointing not only the trends of the nine elements analysed but also their reciprocal correlations. As a consequence it was possible to characterize changes in air pollution composition and the common origin and behavior of several groups of elements.

High light levels together with Paraquat treatment or exposure to pollutants (e.g. SO2) can cause oxidative stress in epiphytic lichens. In some cases, a significant increase in ascorbic acid and other antioxidant metabolites, sometimes occurring in lichens only, was observed. In this study, usnic acid was measured by HPLC in Parmelia caperata and Parmelia soredians thalli treated with Paraquat, a herbicide which transfers electrons from various transport systems to oxygen, producing O2*- superoxide radicals. In light, Paraquat acts by generating active oxygen species within the chloroplast, thus simulating the oxidative component of environmental stress. The significant increase in the usnic acid content measured in P. soredians thalli (+ 36.3%) is in line with the hypothesis that it has an antioxidant action, but it is in contrast to the limited increase measured in P. caperata thalli (+ 13.7%). These apparently contradictory results confirm those found in the literature, which attribute different functions to usnic acid depending on the lichen species considered and on whether they have other detoxifying substances in their thalli. These studies are of potential application-oriented interest in relation to research into new active principles to be used in the pharmaceutical, food and cosmetic fields and/or in environmental biomonitoring.