990 resultados para Mediterranean region


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Moderate resolution remote sensing data, as provided by MODIS, can be used to detect and map active or past wildfires from daily records of suitable combinations of reflectance bands. The objective of the present work was to develop and test simple algorithms and variations for automatic or semiautomatic detection of burnt areas from time series data of MODIS biweekly vegetation indices for a Mediterranean region. MODIS-derived NDVI 250m time series data for the Valencia region, East Spain, were subjected to a two-step process for the detection of candidate burnt areas, and the results compared with available fire event records from the Valencia Regional Government. For each pixel and date in the data series, a model was fitted to both the previous and posterior time series data. Combining drops between two consecutive points and 1-year average drops, we used discrepancies or jumps between the pre and post models to identify seed pixels, and then delimitated fire scars for each potential wildfire using an extension algorithm from the seed pixels. The resulting maps of the detected burnt areas showed a very good agreement with the perimeters registered in the database of fire records used as reference. Overall accuracies and indices of agreement were very high, and omission and commission errors were similar or lower than in previous studies that used automatic or semiautomatic fire scar detection based on remote sensing. This supports the effectiveness of the method for detecting and mapping burnt areas in the Mediterranean region.

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Introduction. In recent years, the global discussion on migration and asylum has evolved from polarization of perspectives and mistrust, to improving partnerships and fostering cooperation between countries and regions. The paradigm has shifted from control and security exclusively to an increased awareness of the ramifications of migration in development and labour markets, the increasing demographic gap1 and the dangers of exclusion faced by migrant workers (regular or irregular). Eastern Europe will suffer the biggest population decline in the coming years, and Nigeria’s population will reach one billion by 2100. In Europe, the work replacement ratio will be two pensioners for one active worker. It has become clear that these facts cannot be ignored and that there is a need for greater convergence of policies (migration/mobility, fundamental rights, and economic growth), with a migrant-centred approach.2. The assumption that Europe will remain a geopolitical and economic hub that attracts immigrants at all skill levels might not hold water in the long run. The evolving demographic and economic changes have made it evident that the competitiveness of the EU (Europe 2020 Strategy) is also at stake, particularly if an adaptable workforce with the necessary skills is not secured in view of shortfalls in skill levels and because of serious labour mismatches. Therefore, it is the right moment to develop more strategic and long-term migration policies that take into account the evolving position of Europe and its neighbours in the world. By the same token, labour market strategies that meet needs and promote integration of regular migrants are still a pending task for the Member States (MS) in terms of the free movement of people, but also in relation with neighbouring and partner countries.

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This MEDPRO Technical Report confirms the importance of commercial openness and macroeconomic performance (i.e. the control of inflation and stability of current account balance and exchange rate) on growth dynamics in the south Mediterranean countries. In particular, the positive impact of capital account liberalisation is conditioned by the imperative reinforcement of institutional quality, country risk reduction, and government stability. An examination of the Tunisian case shows that only sectors subject to tariff dismantlement within the framework of the Association Agreement with the EU appear to benefit from capital account liberalisation. Furthermore, the report shows that a scenario of capital account liberalisation requires the anticipation of monetary policy reaction functions. It follows that the mechanisms for interest rate adjustment, or inter alia, the interest rates’ reaction to price fluctuations, are weakly volatile. In turn, the analysis shows that an active control of inflation mismatches occurs essentially through exchange rate corrections, thus highlighting the greater interest central banks have in exchange rate stability over real stability. A capital account liberalisation scenario would hence impose a tightening of monetary policy.

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Aim To examine the distributional patterns of vertebrates (including birds, bats, carnivores and lagomorphs) along landscape composition and configuration gradients to better understand the effects of landscape modification on occurrence patterns at both species and community level. Location The region of Alentejo, a forest-dominated area of southern Portugal. Methods The study area was framed using 1647 hexagonal plots, each of 259 ha in size. Composition and configuration gradients were obtained for each plot by integrating the proportions of the main land cover types and their configuration patterns using multivariate analyses. Species-specific vertebrate responses were investigated using data from 75 plots in which carnivores, bats and lagomorphs were sampled, and from 135 plots in the case of birds. Community- level responses were investigated through changes in species richness and beta-diversity in 57 plots where all vertebrate groups were simultaneously sampled. At the species-level, an information-theoretic approach was used to determine the effects of landscape gradients on species’ responses. At the community level, Mantel tests were used to determine between-plot differences in species composition using the Sørensen dissimilarity index. Results We found that the occurrence patterns of most vertebrate species were best predicted by composition-related gradients, although configuration gradients were also frequently included in species-specific occurrence models. We also found a weak correlation between species richness and most landscape gradients suggesting a turnover in the identity of species, something that was corroborated by the stronger correlation between environmental gradients and beta-diversity measures. The amount of forest cover and landscape complexity (estimated as the heterogeneity in the size and number of land cover types) were the main composition and configuration gradients determining vertebrate responses at both species and community level. Main conclusions Our work contributes to a more refined understanding of the mechanisms underlying species distributional patterns in real-world human-modified landscapes. By uncovering generalities of species with multiple ecological requirements and by describing the entire landscape mosaic through landscape gradients, we also suggest that our work greatly helps to fill the gap between existing conceptual landscape models aimed to understand species distributional patterns in human-modified landscapes.

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This paper addresses the urgent need for a sustainable energy transition in the southern and eastern Mediterranean region. It analyses the unsustainable burden of universal energy subsidies and calls for new development paths unlocking the huge potential for low-cost energy efficiency and demand-side management as well as for renewable energy. It argues that a new structure of regional and interconnected energy markets is needed. It then proposes some original approaches regarding the financing of this sustainable energy transition and finally calls for an ambitious, Euro-Mediterranean Energy Roadmap, which should contribute not only to the economic and environmental development of the region, but also to its social and political stability.

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This paper presents kinematic analysis on the motion of Adria, which is the continental mass that bridges Africa and Europe in the central Mediterranean. Palaeomagnetic data show a general coherence between the motion of Adria and Africa since the Late Paleozoic. This mutual motion, for the period from 120 Ma and the present, is verified by comparing inferred palaeolatitudes from relatively stable parts of Adria (Apulia, Gargano, Istria, and the Southern Alps) and the Hyblean Plateau, with latitudinal changes that are calculated from the motion of Africa with respect to hotspots. Additional constraints on the motion of Adria are provided from the Late Paleozoic-Early Mesozoic passive margin of Adria in the Ionian Sea. The seismic structure of the floor of the Ionian Sea resembles the structure of the oceanic crust in marginal back-arc basins, suggesting that it formed as a small ocean basin. Furthermore, the Ionian lithosphere in the Calabrian arc has been subjected to rapid rollback, which commonly occurs only when the subducting slab is made of oceanic lithosphere. This oceanic domain marks the Pennian-Triassic to Jurassic plate boundary between Adria and Africa, suggesting that a small amount of independent motion between Adria and Africa took place at that time. Since the Jurassic, Adria and Africa have shared a relatively coherent motion path. (C) 2004 Lavoisier SAS. All rights reserved.

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An earlier study revealed the strong phylogeographical structure of the lesser white-toothed shrew (Crocidura suaveolens group) within the northern Palaearctic. Here, we aim to reconstruct the colonization history of Mediterranean islands and to clarify the biogeography and phylogeographical relationships of the poorly documented Middle East region with the northern Palaearctic. We performed analyses on 998-bp-long haplotypes of the mitochondrial cytochrome b gene of 143 samples collected around the Mediterranean basin, including islands and the Middle East. The analyses suggest that the Cypriot shrew belongs to the rare group of relict insular Pleistocene mammal taxa that have survived to the present day. In contrast, the Cretan, Corsican and Menorcan populations were independently introduced from the Middle East during the Holocene. The phylogeographical structure of this temperate Palaearctic species within the Middle East appears to be complex and rich in diversity, probably reflecting fragmentation of the area by numerous mountain chains. Four deeply divergent clades of the C. suaveolens group occur in the area, meaning that a hypothetical contact zone remains to be located in central western Iran.

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The location and timing of domestication of the olive tree, a key crop in Early Mediterranean societies, remain hotly debated. Here, we unravel the history of wild olives (oleasters), and then infer the primary origins of the domesticated olive. Phylogeography and Bayesian molecular dating analyses based on plastid genome profiling of 1263 oleasters and 534 cultivated genotypes reveal three main lineages of pre-Quaternary origin. Regional hotspots of plastid diversity, species distribution modelling and macrofossils support the existence of three long-term refugia; namely the Near East (including Cyprus), the Aegean area and the Strait of Gibraltar. These ancestral wild gene pools have provided the essential foundations for cultivated olive breeding. Comparison of the geographical pattern of plastid diversity between wild and cultivated olives indicates the cradle of first domestication in the northern Levant followed by dispersals across the Mediterranean basin in parallel with the expansion of civilizations and human exchanges in this part of the world.