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Virgin Olive Oil (VOO) shelf life is determined by the varietal-specific chemical composition and principally by the of phenolic composition. The aim of this study was to investigate the changes in fatty acid profile, phenolic composition, and quality parameters of nine Italian monovarietal VOOs obtained under the same pedoclimatic, agronomic and technological conditions and stored for 12 months at 15 degrees C in the dark. The varieties with medium-high concentrations of secoiridoids and balanced values between the individual molecules were those with the highest stability. Orthogonal Projections to Latent Structures (OPLS) regression revealed that oleuropein derivatives and phenolic alcohols had the highest antioxidant activity. OPLS discriminant analysis separated well fresh and stored oils. PV, K270, tyrosol, hydroxytyrosol, and oxidated oleacein were the most effective indicators of VOO ageing. Oleacein and oleocanthal decreased after storage, phenolic alcohols, oleacein and ligstroside aglycon increased.

Sustainable forest management (SFM) is crucial for forest ecosystem productivity and conservation, especially in systems such as cork oak (Quercus suber L.) threatened by human activities and biotic and abiotic factors. In this study SFM indicators with particular reference to cork oak forests in the region of Sardinia (Italy) are proposed and tested. Sustainable and responsible management options specifically aimed at cork oak forest management and chain of custody certification are also provided. A set of ten indicators was proposed and assessed by an expert panel in cork oak management. Five indicators were also tested against data on structure, origin, health condition and management in 285 forest compartments managed by FoReSTAS (Regional Forest Agency for Land and Environment of Sardinia, Italy), including 361 sampling plots and 5345 trees. In order to investigate the priorities and perceptions of SFM experts and stakeholders, a survey was also carried out by completion of a questionnaire on the technical issues of cork oak woodland management. The survey results highlighted a need to improve environmental and economic performance by means of SFM and certification. The indicators tested in Sardinian cork oak woodlands showed that about 80% of the stands fulfilled management sustainability requirements. The suggested SFM indicators can effectively support proactive management and conservation measures, representing a valuable tool in the current context of growing environmental and socioeconomic awareness.

A spatially explicit approach for stand-scale economic valuation of current and future potential of cork forests with respect to ecosystem production is developed and presented. The approach, which relies in large part on the mensuration of stand top height and number of trees as main drivers, has been tested on the pure cork forests of Sardinia (Italy). The test was conducted to assess the effects of alternative silvicultural options on cork and fodder production, carbon sequestration, and water yield. Under current conditions, the surveyed pure cork oak forest stands in Sardinia are characterized, on average, by an annual economic production of 93 euro ha-1 yr-1 as concerns cork, 37 euro ha-1 yr-1 as concerns carbon sequestration and 261 euro ha-1 yr-1 as concerns water yield. The value of cork production on an 11-year cycle equals 1023 euro ha-1 on average. The total economic production values among the tested silvicultural alternatives have proven to be characterized by relatively small differences, due to the trade-offs among the considered goods and services. Therefore, at least under conditions similar to those surveyed, managers may safely rely on different stand density options, without any relevant detrimental effect on total economic production. The tested spatial visualization of the economic values of goods and services production can be useful in supporting forest management planning, e.g., to identify priority areas in order to maximize ecosystem production for local communities. The approach proposed here and tested to this end proves to be readily applicable to other cork contexts with similar characteristics under Mediterranean conditions.

The olives are rich in microorganisms that, during the extraction process may persist in the oils and can influence their physicochemical and sensory characteristics. In this work, and for the first time, we isolated and identified microbial species, yeast and bacteria, present during the production process in four Sardinian (Italy) oleic ecosystems. Among these varieties, we found that Nera di Gonnos was associated to the highest microbial biodiversity, which was followed by Bosana, Nocellara del Belice and Semidana. Among the different microbial species isolated, some are specific of olive ecological niches, such as Cryptococcus spp and Serratia spp; and others to olive oils such as Candida spp and Saccharomyces. Some other species identified in this work were not found before in oleic ecosystems. The enzymatic analyses of yeast and bacteria showed that they have good β-glucosidase activity and yeast also showed good β-glucanase activity. The majority of bacteria presented lipolytic and catalase activities while in yeast were species-specific. Interestingly, yeast and bacteria isolates presented a high resistance to bile acid, and about 65% of the yeast were able to resist at pH 2.5 for 2 h. Finally, bacteria showed no biofilm activity compared to yeast.

Virgin olive oil (VOO) provides an important source of healthy compounds. Its high concentrations of monounsaturated fatty acids and phenolic compounds contribute toward its nutritional, antioxidant, and antimicrobial properties. VOO is used in the preparation of many dishes worldwide and forms a staple of the Mediterranean diet; however, the antimicrobial activity of VOO in food matrices has been investigated very little to date. Considering this and the growing demand to reduce the use of synthetic antimicrobials and chemical food preservatives, especially in minimally processed foods, the aim of this work was to evaluate the antibacterial activity of VOOs obtained from 13 different Italian olive varieties. All olive varieties were harvested and processed in the same area (Oristano, Sardinia, Italy). The in vitro antimicrobial activities of the resulting VOOs were tested against: Listeria monocytogenes DSM 20600, Staphylococcus aureus DSM 20231, Escherichia coli DSM 30083, Salmonella bongori DSM13772, Lacticaseibacillus casei Shirota, Limosilactobacillus reuteri DSM 17938, Lacticaseibacillus casei RI4, and the yeast Candida albicans 3393. Orthogonal Projections to Latent Structures (OPLS) analysis showed a strong correlation between the content of certain phenolic compounds, the contact time of VOOs with the microbial cells, and the antimicrobial activity of the VOOs against the microorganisms tested. The VOOs showing the strongest antimicrobial activities (the Bosana and Sivigliana varieties) were then re-tested against L. monocytogenes DSM 20600 and S. bongori DSM 13772 in artificially contaminated commercial quick salad bags (QSB) of baby green leaf lettuces. The results show that antimicrobial activities of VOO depend on the target microbial species and the concentration of the inoculum. This study provides evidence supporting that VOOs with determinate polyphenols profiles might be used as antimicrobial ingredients in minimally processed foods to significantly reduce the presence of pathogenic bacteria.

The complexity of the Italian Peninsula, characterized by heterogeneous bioclimates, soils, landscapes, and cultures, made possible to preserve the richest world’s olive biological diversity. Most of the Italian varieties are strictly connected to their typical growing areas and well adapted to specific bioclimates. Therefore the Italian olive oil sector is characterized by a high diversity of products, which are the results of varietal-specific interactions with environmental, agronomic, and technological factors. Throughout this chapter the virgin olive oil (VOO) composition of the most relevant Italian varieties and the factors influencing their quality were described. All the Italian varieties contain intrinsic high and unique potential of antioxidant bioactive molecules. Thanks to agronomical and technological innovations, is possible to get the best VOO quality, that really effective in providing benefits for human health.

Wildland fires represent a major threat to Quercus suber L. ecosystems, which provide relevant socioeconomic and ecological services in the Mediterranean Basin. In this work, we analyzed recent wildland fire dynamics in cork oak woodlands along the fire-prone areas of Sardinia (Italy), Corsica (France) and Catalonia (Spain). We first characterized geographic extent and main characteristics of cork oak woodlands in these regions and analyzed how environmental (climate and elevation) and socioeconomic factors (population and land uses) vary in the areas covered by Quercus suber L. We then evaluated how wildfires affected cork oak stands and, by logistic regression analysis, to what extent wildfires in cork oak areas were related to the above set of environmental and anthropic explanatory variables. Results revealed specific variations across study areas in cork oak characteristics as well as in environmental and social factors. We highlighted the spatial and temporal patterns of wildfires on cork oak woodlands, in terms of extent, seasonality, frequency and main driving factors. In the period 2003–2015, the percentage of cork oak woodlands burned ranged from 3.42% in Corsica to 11.30% in Sardinia. A few large and severe wildfires accounted for most of the area burned in cork oak woodlands. The most significant predictive variable that explained the spatial variation in wildland fire ignitions inside or nearby cork oaks was summer precipitation, while the weight of other factors varied depending on the region. This study provides evidence on recent fire dynamics in cork oak woodlands and gives valuable information and insights for the implementation of forest management and planning strategies in the Mediterranean area. This work was supported by the Sardinia Region under the project “Multifunzionalità delle foreste a quercia da sughero in Sardegna” (Multifunctionality of cork oak forests in Sardinia) funded within L.R. n. 7/2007 “Promozione della ricerca scientifica e della innovazione tecnologica in Sardegna,/Tender no. 2″, and by the “Proterina-2” Project funded by the Italia Francia-Marittimo Programme.

Land cover change analyses are common and, especially in the absence of explanatory variables, they are mainly carried out by employing qualitative methods such as transition matrices or raster operations. These methods do not provide any estimation of the statistical significance of the changes, or the uncertainty of the model and data, and are usually limited in supporting explicit biological/ecological interpretation of the processes determining the changes. Here we show how the original nearest-neighbour contingency table, proposed by Dixon to evaluate spatial segregation, has been extended to the temporal domain to map the intensity, statistical significance and uncertainty of land cover changes. This index was then employed to quantify the changes in cork oak forest cover between 1998 and 2016 in the Sa Serra region of Sardinia (Italy). The method showed that most statistically significant cork oak losses were concentrated in the centre of Sa Serra and characterised by high intensity. A spatial binomial-logit generalised linear model estimated the probability of changes occurring in the area but not the type of change. We show how the spatio-temporal Dixon’s index can be an attractive alternative to other land cover change analysis methods, since it provides a robust statistical framework and facilitates direct biological/ecological interpretation.

Virgin olive oils (VOOs) merceological, sensorial, and nutritional quality factors have been widely investigated in the last decades. While the effects of genetic, transformation related and agronomic factors on quality oil production seem clear, more uncertainties or discordant results show the influence of cultivation environment and, in particular, of soil characteristics and climatic conditions [1,2]. We present the research results of the last three years on chemical and nutritional characteristics of monovarietal VOOs of some of the varieties included in the PDO 'Sardegna'. Within these varieties, genetic groups expressed some specific characteristics (phenolic profile, fatty acid or sterolic composition) and may contribute in different way to the quality of VOOs: high content of polar phenols, particularly secoiridoids; high content in oleic acid and MUFA/PUFA ratio. Local cultivars have proved also to be a good source of squalene and sterols. Furthermore, datasets of specific cultivars were analyzed to verify the influence cultivation environment on VOOs quality. VOOs from Sardinia (Italy) were studied through an NMR-based metabolomics approach, in order to distinguish the samples based on the olive growing areas, classified on the basis of FAO-UNEP. NMR profiling presents a connection between environmental factors of Sardinian cultivation areas and the chemical composition of EVOO. An NMR-based metabolomic approach that uses six "one-to-one" OPLS-DA models allowed us to discriminate the different influence of evapotranspiration, solar exposure, and altitude on the chemical composition of VOOs [3]. Regarding the influence of soil composition on quality oil, statistical filtering was used to identify year influence on data, and transform old dataset obtaining a new dataset in which year influences are minimized and soil effects are maximized. Statistical analysis showed the influence of soil composition on phenolic molecules which are responsible of aromatic and nutraceutical properties. NMR and HPLC methodologies were confirmed as an important tools for characterizing virgin olive oil and determining the influence of environmental factors on oil quality.

Fatty acids, phenolic compounds, and tocopherols of Coratina, Bosana, Semidana, and Tonda di Cagliari virgin olive oils, were measured over a 45-day harvest period. Phenolic composition was the primary factor distinguishing Bosana, Tonda di Cagliari, and Semidana, whereas fatty acids differentiated Coratina and the other cultivars. Harvest period principally influenced oleacein, oleocanthal, oleuropein and ligstroside aglycones, and flavonoids. High phenolic content was observed for Coratina (1039–688 mg/kg) and Bosana (788–592 mg/kg). A drastic decrease in phenolic content was observed in Semidana (529–134 mg/kg) and Tonda di Cagliari (507–142 mg/kg) during the harvest period. These two cultivars also had low MUFA/PUFA (6.0–4.0 and 4.9–3.2 respectively), suggesting that these varieties should be harvested earlier in the season. These results provide information to producers for improved management of the harvesting process, which is strongly affected by varietal factors.

This study analyses the extent and spatial distribution of the forest resources and their energy potential in the province of Nuoro (Sardinia, Italy). The aim is to create a data base which will help decision makers to make a plan for the sustainable use of the resources of the territory. A GIS-based model was used to assess the energy capacity and suitability of the area. This model used four basic information layers: (1) slope, (2) hydro-geological constraints, (3) protected areas, (4) forest districts under regional forest management. These four criteria are of great importance when attempting to assess the quantity of available sustainable biomass. Based on their potential energy production, 140 basins were identified, which could provide enough forest biomass to fuel all the heating systems currently installed in public buildings of the Provincial administration.

The chemical composition affects the sensory properties and quality of Extra Virgin Olive Oil (EVOO). In addition, its knowledge can supply valuable information about the cultivar and its geographical origin. The goal of this study is to obtain a protocol in order to be able to recognize the composition of various Sardinian oils and to consequently correlate them with their production areas. High-resolution 1H NMR spectroscopy was used to analyze 100 (82 training + 18 test sets) samples of EVOO from the Bosana cultivar, collected from different growing areas in Sardinia (Italy). Growth areas were classified on the basis of FAO-UNEP aridity index. NMR data were processed with multivariate statistical analysis. NMR profiling presents a connection between environmental factors of Sardinian cultivation areas and the chemical composition of EVOO. An NMR-based metabolomic approach that uses six “one-to-one” OPLS-DA models allowed us to discriminate the different influence of evapotranspiration, solar exposure, and altitude on the chemical composition of Bosana EVOO. Practical Applications: Detailed knowledge of NMR spectra pattern variations could have a potential impact on olive oil market. The application of the 1H NMR metabolomic, based on chemometric models, can be a useful tool in order to certificate the geographical origin of EVOO. An NMR-based metabolomic approach,using “one-to-one” OPLS-DA models, allows to identify biomarkers of different production zones in “Bosana” Sardinian EVOO.

The Congress is intended as a forum for sharing Mediterranean experiences in the cork industry: from the conservation and sustainable management of cork forests to the aspects of industrial processes and alternative uses to cork stopper production. The Congress is held in Sardinia, an island in the centre of the Western Mediterranean, where many rural landscapes are characterised by cork trees, which thus have environmental and economic value, and, hence also social value.

People perceive living landscapes in different ways: a car driver does not have the same view of landscape as a passenger; a person on a boat experiences landscape and seascape differently from a person on shore. Moreover, the perception of living landscapes depends on the way people are aware of landscape experience.

Cork oak is one of the most valuable natural forest genera in the Mediterranean basin. Modelling cork oak growth has been a challenge for foresters in recent years because of strong site and genetic influences, below-ground competition, management regimes and age effects. Because cork productivity is related to forest height, which is, in turn, related directly with site characteristics, an increase in the accuracy of height prediction implies improved productivity estimation. A Bayesian maximum entropy (BME) geostatistical model was applied to characterize the space-time pattern of height of young cork oak in a forest stand from central Sardinia in the years 2000, 2002, 2003, 2006 and 2008. Cork oak height maps were produced for each of the 5 years. The main goals were to analyse and interpret through time (i) the changes in spatial correlation and (ii) the changes in spatial distribution of cork oak height. The plantation was characterized by an increasing spatial dependence through time, whereas the temporal range was 2 years. Cork oak height was significantly correlated with wind speed (reduced by a neighbouring forest) in all the years implying a single trend. The correlations were larger for 2006 and 2008 than for previous years. Three other environmental variables (shade, elevation and slope) were less significant and their influence restricted to 2 years only. This research has several implications for the management of cork oak in the young phase.

Recently, significant forestry activities have taken place in Sardinia thanks to EU Regulation 2080/92 funds. Some 80% of the afforestated surface has been planted with holm oak and cork oak. The latter also characterizes 89% of the reforestation area. Given the funding source, plantations have been established on farmlands. Growth performances of these recent cork oak stands have been quantitatively evaluated and compared with the performances of two experimental plots. In Gallura (north-east of Sardinia), that is the traditional cork production area and still is economically the most important cork district of the island, these new cork oak plantations have an average size of 28 ha. They have been established on lands that, before plantation, were either pastures (30%) or arable lands (70%). Plantation failures are limited to 8.8% of the total (in term of mass) and seem independent of environmental factors or plantations species composition (conifers have been frequently used as secondary species). Average growth of the stem, measured above cork at collar height, is in the range 4 to 8mm/year with a mean value of 5.5mm/year. No correlation appears with either environmental conditions or species composition of the plantations. In the first experimental plot, soil management practices (natural vegetation removal vs. its cutting and mulching) does not differentiate young plants growth trends. In the control subplots (no removal) stem collar diameter is 20% smaller. Localized manual hoeing around trunk base increased the diameters by 13% but reduced cork thickness by 21%. The second experimental plot allows comparisons among 27 Mediterranean proveniences of cork oak. The trial exhibits reduced genetic influence: diameters and heights growth are significantly different only among extreme groups. In conclusion, reduced growth performances of the plantations established in farmlands is due, to some extent, to the limitations inherent with private land management (constrained to costs minimization) and, on the other hand, to the generally very limited thickness of Gallura soils. Demand for good quality commercial cork is steadily raising. To sustain the request, in the short term, it would be necessary to extend financial support for plantations care, from 5 to 10 years, or even up to the first stripping (virgin cork).

Geostatistics provides tools to model, estimate, map and predict spatial patterns of tree size and growth. Variogram models were used to study spatial dependence of basal diameter in young cork oak plantation. Our objective was to determine the spatial dependence of stand by studying the related spatial stochastic model. Despite the fact that high nugget effects affect the model for whole area, cork oak diameter shows a better spatial dependence in the two different geological classes that divide the area. An isotropic exponential and an isotropic spherical variogram were the models chosen to represent granite and quartzite subareas. In both models, cork oak diameter was spatially autocorrelated over distances no greater than 8 m, a measure of average patch diameter in this forest ecosystem. The results of survey suggest that geology exerts a strong control on cork oak diameter variation, and in the whole area that other factors are also involved, such as elevation, soil depth, catchment area, slope, hillshade and aspect are creating a general random effect. Simulation models and area estimates of tree performance in young or old-growth forests may be improved by including geostatistical components to summarize ecological spatial dependence.

The objective of this paper is to present the results of a long-term research project carried out in north-east Sardinia, which aims to evaluate the effects of three different kinds of forest management (traditional trunk coppicing, branch pruning, and no sylvicultural practice) on the post-fire recovery of a cork oak (Quercus suber L.) stand. The most and the least effective forestry operations appeared to be traditional trunk coppicing and the branch pruning, respectively. Where traditional trunk coppicing is considered strictly necessary, the opportunity of thinning some of the new suckers should be carefully considered, as modern harvesting techniques should be combined with appropriate strategies to protect the soil from erosion.

The international network of provenance and progeny trials was established in 1998 benefiting from homogeneous plant raising and standardize experimental design. The trials include 34 provenances that are being characterised by several teams. France 2008. Provenance PT 23 and PT+ES 25 had the lowest survival rate. In 2008 the mean height was 48.73 cm and the form keeps plagiotropic. Italy- Sardinia, 2010 - The average mortality was 7%. Mean height and trunk DBH over cork were respectively 273 and 5.1 cm. MO I-2, TU II, ES 4-CR are above mean on height (302-309 cm), and the Italian provenances are under mean (237-249cm). Italy- Roccarespampani, Lazio- The mortality is about 45% and it is the only plantation site where the French provenance FR3 has a growth above mean. Portugal. Results show significant differences among populations on survival and growth. The Moroccan provenances show good adaptive characteristics in terms of growth, vigour and stem form. Italian provenances present lower height but higher survival. The overall mortality is around 26%. The highest growth is being observed in the Moroccan provenances and French ones showed lowest survival. Provenances and plantation sites are characterised for rainfall regime. The provenances Morocco MA27 and Tunisia TU33 that are from sites of high rainfall are among the best on growth at sites of considerable more xerothermic climate. If persistent at older age these results indicate that fast adaptation of cork oak populations to cope with climate changes leading to drier and warmer conditions seems possible. Concerted Action FAIR 202 “European network for the evaluation of genetic resources of cork oak for appropriate use in breeding and gene conservation strategies” info:eu-repo/semantics/publishedVersion

Cork harvesting and stopper production represent a major forest industry in Sardinia (Italy). The target of the present investigation was to evaluate the ‘‘classification tree’’ as a tool to discover possible relationships between microsite characteristics and cork quality. Seven main cork oak (Quercus suber) producing areas have been identified in Sardinia, for a total of more than 122,000 ha. Sixty-three sample trees, distributed among different geographical locations and microsite conditions, were selected. A soil profile near each sample tree was described, soil samples were collected and analysed. After debarking, cork quality of each sample tree was graded by an independent panel of experts. Microsites where trees had more than 50% of the extracted cork graded in the best quality class, according to the official quality standard in Italy, were labelled as prime microsites, the others as nonprime microsites. Relationships between a binary dummy variable (0 for nonprime microsites, 1 for prime microsites) and site factors were investigated using classification tree analysis to select the relevant variables and to define the classification scheme. Prime quality microsites for cork production proved to be characterised by elevation, soil phosphorus content and sandiness. Results have been compared with those of the more conventional parametric approach by logistic regression. The work demonstrates the advantages of the classification tree method. The model may be appropriate for classifications at landscape and stand mapping levels, where it is possible to sample a number of microsites and to evaluate distributional characteristics of model output, while its precision is only indicative when estimating the prime quality of single microsites. L'articolo è disponibile sul sito dell'editore www.springerlink.com

Considering the very high socio economic value of cork oak (Quercus suber L.) in Mediterranean areas, a better knowledge of local genetic resources is necessary in order to reach a good balance between the conservation issues and the need of an efficient cork production network. In such frame, local germplasm of Q. suber from the main cork production areas of Sardinia was analysed for DNA and isozyme polymorphisms and for cork quality in relation to some environmental parameters. A total number of 24 sample stands of cork oak were selected, representing typical vegetation, sylvicultural and cork quality features within the eight identified cork growing areas in Sardinia. Considerable variation was found between cork oak stands of the different areas. Results of the principal component analysis performed on the cork quality data and environmental characters of the eight areas, showed that the first three components explain 72.2% of the variation. The major characters involved in this differentiation were cork quality characters such as dimensional recover, moisture and Mg content of the cork and also elevation of stands m a.s.l. for the first component. The second component appears to be determined by some climatic parameters (average annual temperature and average of the minimum temperatures of coldest month) and by the Fe and Zn in the cork. For the third component, major characters involved in differentiation are average annual rainfall, bark thickness and Ca content in the cork.

The island of Sardinia is the biggest producer of natural cork in Italy. In this study, cork oak cover change is investigated in a typical agro-silvopastoral system where the main activities are cereal fodder and wheat cultivation, sheep rearing and cork exploitation. The research method is based on the comparison of two land use maps produced by photo-interpretation of digitised aerial photographs taken in 1954 and 1998, combined with interviews with local farmers, field surveys, and data collected from literature, administrative documentation and decadal censuses (at council level). The results show that the cork oak woodland surface decreased (-29%). It was substituted by other forest, ploughed land, and mixed grassland and shrubland. Apart from the transformation of the cork oak woodland to other forest, other changes have happened probably because of an increase in agricultural and pastoral activities as described by the documental material available for the same area.