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A geochemical comparison of early Palaeozoic felsic magmatic episodes throughout the south-western European margin of Gondwana is made and includes (i) Furongian–Early Ordovician (Toledanian) activities recorded in the Central Iberian and Galicia–Trás-os-Montes zones of the Iberian Massif, and (ii) Early–Late Ordovician (Sardic) activities in the Eastern Pyrenees, Occitan Domain (Albigeois, Montagne Noire and Mouthoumet massifs) and Sardinia. Both phases are related to uplift and denudation of an inherited palaeorelief, and stratigraphically preserved as distinct angular discordances and paraconformities involving gaps of up to 22 million years. The geochemical features of the predominantly felsic Toledanian and Sardic activities point to a predominance of magmatic byproducts derived from the melting of metasedimentary rocks, rich in SiO 2 and K 2 O and with a peraluminous character. Zr / TiO 2 , Zr / Nb, Nb / Y and Zr vs. Ga / Al ratios, and rare-earth element (REE) and ε Nd (t) values suggest the contemporaneity, for both phases, of two geochemical scenarios characterized by arc and extensional features evolving to distinct extensional and rifting conditions associated with the final outpouring of mafic tholeiite-dominant lava flows. The Toledanian and Sardic magmatic phases are linked to neither metamorphism nor penetrative deformation; on the contrary, their unconformities are associated with foliation-free open folds subsequently affected by the Variscan deformation. The geochemical and structural framework precludes subduction-generated melts reaching the crust in a magmatic arc-to-back-arc setting and favours partial melting of sediments and/or granitoids in the lower continental crust triggered by the underplating of hot mafic magmas related to the opening of the Rheic Ocean. [ABSTRACT FROM AUTHOR]

A germination study was carried out on seeds ofClinopodium sandalioticum(Bacch. & Brullo) Bacch. & BrulloexPeruzzi & Conti (Lamiaceae), a wild aromatic plant endemic to Sardinia. Seeds were incubated at a range of constant (5–25°C) and an alternating temperatures regime (25/10°C), with 12 hours of irradiance per day. The results achieved at 10°C were also compared with those obtained after a period of cold stratification at 5°C for three months. Final seed germination ranged from ca. 28% (5°C) to ca. 72% (25/10°C). A base temperature for germination (Tb) of ca. 5°C and a thermal constant for 50% germination (S) of 89.3°Cd were identified and an optimal temperature for germination (To) was estimated to be comprised between 20 and 25°C. Cold stratification negatively affected seed viability and germination at 10°C. Although a typical “Mediterranean germination syndrome”, could not be detected forC. sandalioticumseeds, these results were coherent with those previously reported for other Mediterranean Lamiaceae species. [ABSTRACT FROM AUTHOR]

This article provides a comparison of the vascular alien flora of Sardinia (Italy) and that of Corsica (France), both territories belonging to the Western Mediterranean biogeographic subregion. The study has recorded 598 (90 doubtful) alien taxa in Sardinia (18% of the total flora) while 553 (87 doubtful) in Corsica (17%); six are new report to Sardinia and 27 to Corsica. A total of 234 taxa are common to both islands. Neophytes are 344 taxa (68% of the total) in Sardinia and 399 taxa (73%) in Corsica. The invasive component includes 64 taxa in Sardinia (13% of the alien flora) and 99 taxa (21%) in Corsica, 33 of them common to both territories. The total 740 alien taxa of Sardinia and Corsica are included in 93 families; being Fabaceae the richest. The comparison of the biological spectrum reveals that phanerophytes (202 taxa, 40%) are the most represented in Sardinia and therophytes (149 taxa, 32%) in Corsica. A study of the geographical origin shows supremacy of the American element in Sardinia (170 taxa, 34%) and in Corsica (136 taxa, 29%). The majority of taxa arrived as a result of intentional human introductions, mainly for ornamental use (247 taxa, 49% in Sardinia; 208 taxa, 45% in Corsica). Seminatural, agricultural and synanthropic are the most occupied habitats. These data show the need for joint action to stem the increasingly worrying phenomenon of the alien flora in order to reduce the negative effects on natural habitats and native flora. [ABSTRACT FROM AUTHOR]

Recent genetic studies suggest a Sardinian type of amyotrophic lateral sclerosis (ALS). Thus, ALS incidence, prevalence and survival were investigated in a large population of Sardinians aimed to disclose population-specific patterns and their temporal changes. This is a population-based incidence and prevalence study in northern and central Sardinia, insular Italy (over 700,000 population). Incidence rates were computed for the time interval 1995-2009 and by quinquennia. Prevalence was computed for prevalence days 31 December 2004 and 2009. Onset-based survival for 1995-2009 is also reported. All ALS patients (El Escorial Criteria) in the study area were retrospectively included. The ALS crude incidence from 2005-2009 was 2.5 (95 % CIs: 0.1, 4.9), 3.4 in men and 1.6 in women. Onset occurred most often between the age of 65-74 years in men and 55-64 years in women. The ALS incidence tended to increase over the period 1995-2009. The mean age at onset was 61.7 years with no difference based on gender, varying significantly from 59.9 years in 1995-1999 to 63.9 years in 2005-2009. On December 31, 2009, the ALS crude prevalence was 10.8 per 100,000 (95 % CIs: 8.6, 13.1), 13.8 in men and 8.0 in women, whereas it was 6.3 per 100,000 (95 % CIs: 4.1, 8.6) on December 31, 2004 (M:F ratio of 0.95). Mean survival from onset was 37.0 months, with no difference based on gender, and a tendency to decrease during the period 1995-2009, in relation to type and age of onset. The population-based incidence and prevalence data of ALS in Sardinians indicate an increase of the disease occurrence over the past 40 years, providing support for a population-specific variant of ALS in Sardinia. [ABSTRACT FROM AUTHOR]

The Mediterranean basin is one of the most important biodiversity hotspots. However, only 5% of its original vegetation is still in place, and the landscape has been managed and transformed by humans for at least the last two millennia. In the last century the mechanization of agriculture and the over-use of semi-natural habitats have influenced the region even more than before, with huge consequences, especially on islands. Sardinia is the second largest island in the Mediterranean basin, and it has been considered for long as a semi-natural area with an economy based on traditional agroforestry and pastoral practices. Considering four maps covering Sardinia and ranging from 1935 to 2007, we measured the rate of forest changes demonstrating a constant trend towards forest increase, and with a complete recovery of the total forest surface compared to the late 1800s. The traditional agroforestry practices decrease in time due to socio-economic reasons, with deeper consequences for the mosaic of traditional agricultural areas and semi-natural habitats, as well as for the conservation of the unique biodiversity of Sardinia. Species typically linked to Mediterranean forests recovered and are recovering, while species linked to traditional semi-natural landscapes decreased, facing conservation problems. We suggest that the current challenges for biodiversity conservation in the island should be focused together with the agricultural policies towards the preservation and improvement of traditional open areas, even important in the history of the entire Mediterranean hotspot. [ABSTRACT FROM AUTHOR]

Temporary rivers are characterized by recurrent dry phases, and global warming will stress their hydrology by amplifying extreme events. Microbial degradation and transformation of organic matter (OM) in riverbed sediment are key processes with regard to carbon and nutrient fluxes. In this study, we describe structural and functional changes of benthic microbial communities in a riverine environment subject to hydrological fluctuation. Sampling was carried out in the outlet section of the Mulargia River (Sardinia, Italy) under various water regimes, including one flood event. Overall, sediments were characterized by low bacterial cell abundance (range 0.6-1.8 × 10 cell g) as a consequence of their low nutrient and OM concentrations. No major differences were found in the community composition. Alpha- Proteobacteria dominated during the whole year (range 21-30%) followed by Beta- Proteobacteria, Gamma- Proteobacteria, and Cytophaga- Flavobacteria which always contributed <18%. Planctomycetes and Firmicutes were found in smaller amounts (<7%). In spring, when the highest total organic carbon content was also detected (0.42% w/w), both bacterial abundance and C production (BCP, 170 nmol C h g) reached relatively high values. During the flood event, an increase in BCP and the highest values of community respiration (CR, 74 nmol C h g) were observed. Moreover, most of the extracellular enzyme activities (EEA) changed significantly during the flood. The variation of the water flow itself can explain part of these changes and other factors also come into play. The presence of different patterns of functional parameters could suggest that the quality of the OM could be the major driving force in nutrient flux. [ABSTRACT FROM AUTHOR]

The Corsican red deer, a sub-species of the European red deer endemic to Sardinia and Corsica, was abundant on both islands at the beginning of 1900. It went extinct in Corsica and reached a minimum of 100 individuals in Sardinia by 1970. Numbers have recovered in Sardinia with more than 1,000 rutting males now present; in the 1980s the deer was reintroduced to Corsica, but the Sardinian population remains fragmented. We developed a potential distribution model in Sardinia using Ecological Niche Factor Analysis. To assess the deer's protection status we compared the model with the existing and proposed conservation areas and investigated different conservation scenarios in relation to the expansion of its current range and resilience to future changes in land use and predicted trends of desertification. According to our results over 70% of Sardinia is unsuitable to the deer, nevertheless high suitability areas (Mediterranean forests away from main roads) are available throughout the island, particularly in the south and in the central-eastern part. Existing protected areas do not provide for the conservation of the deer but public owned forests, where hunting is prohibited, extend some level of protection, and the protected areas proposed by the Regional administration, if implemented, will be increasing this protection. Three main areas have emerged as conservation priorities to guarantee adequate conservation potential in the future. Our approach provides valuable data to inform conservation policy, and could be easily replicated in other parts of the Mediterranean. [ABSTRACT FROM AUTHOR]

With the development of intensive care, the survival of extremely low-birthweight (ELBW) infants (<1,000 g) has greatly improved. The aim of our study was to report the incidence of epilepsy after a follow-up of >7 years in a population of ELBW children, born in central and southern Sardinia between 1991 and 2000. We analyzed data of 104 children. All infants had had serial cranial ultrasound echography (CUE) in the neonatal period and some also had magnetic resonance imaging (MRI). At last follow-up we evaluated the occurrence of epilepsy through a review of clinical charts and a structured telephone interview. In 11 (10.6%) of 104 of children we observed febrile seizures (FS). Epilepsy occurred in 9 (8.6%) of 104 ELBW children, and in these patients a frequent positive family history for epilepsy and/or FS was present. In four epilepsy patients CUE was highly pathologic, showing intraventricular hemorrhage (IVH) of grade IV and in two mildly abnormal (IVH of grade I–II). In three additional children with normal neonatal ultrasound scan, a later magnetic resonance imaging (MRI) study revealed lesions related to neonatal insult. In our ELBW population, epilepsy had an incidence clearly superior to that expected in infancy (8.6% vs. 0.6–0.8% ). A frequent positive familiar history for epilepsy and/or FS suggests that a genetic predisposition may also play a role. Subjects with highly abnormal CUE are a subgroup with high risk for seizures; however, epilepsy can occur even with normal CUE. [ABSTRACT FROM AUTHOR]

A new project was recently initiated for the realization of the “Land Unit and Soil Capability Map of Sardinia” at a scale of 1:50,000 to support land use planning. In this study, we outline the general structure of the project and the methods used in the activities that have been thus far conducted. A GIS approach was used. We used the soil-landscape paradigm for the prediction of soil classes and their spatial distribution or the prediction of soil properties based on landscape features. The work is divided into two main phases. In the first phase, the available digital data on land cover, geology and topography were processed and classified according to their influence on weathering processes and soil properties. The methods used in the interpretation are based on consolidated and generalized knowledge about the influence of geology, topography and land cover on soil properties. The existing soil data (areal and point data) were collected, reviewed, validated and standardized according to international and national guidelines. Point data considered to be usable were input into a specific database created for the project. Using expert interpretation, all digital data were merged to produce a first draft of the Land Unit Map. During the second phase, this map will be implemented with the existing soil data and verified in the field if also needed with new soil data collection, and the final Land Unit Map will be produced. The Land Unit and Soil Capability Map will be produced by classifying the land units using a reference matching table of land capability classes created for this project. [Copyright &y& Elsevier]