926 resultados para Central Europe


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Many studies have examined whether communities are structured by random or deterministic processes, and both are likely to play a role, but relatively few studies have attempted to quantify the degree of randomness in species composition. We quantified, for the first time, the degree of randomness in forest bird communities based on an analysis of spatial autocorrelation in three regions of Germany. The compositional dissimilarity between pairs of forest patches was regressed against the distance between them. We then calculated the y-intercept of the curve, i.e. the ‘nugget’, which represents the compositional dissimilarity at zero spatial distance. We therefore assume, following similar work on plant communities, that this represents the degree of randomness in species composition. We then analysed how the degree of randomness in community composition varied over time and with forest management intensity, which we expected to reduce the importance of random processes by increasing the strength of environmental drivers. We found that a high portion of the bird community composition could be explained by chance (overall mean of 0.63), implying that most of the variation in local bird community composition is driven by stochastic processes. Forest management intensity did not consistently affect the mean degree of randomness in community composition, perhaps because the bird communities were relatively insensitive to management intensity. We found a high temporal variation in the degree of randomness, which may indicate temporal variation in assembly processes and in the importance of key environmental drivers. We conclude that the degree of randomness in community composition should be considered in bird community studies, and the high values we find may indicate that bird community composition is relatively hard to predict at the regional scale.

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Peat deposits from an ombrotrophic bog (north-eastern Poland) were analysed to reconstruct peatland development and environmental changes. This paper presents reconstructions of hydrological changes and plant succession over the last 6000 years. The methods included the high-resolution analysis of plant macrofossils, pollen and testate amoebae, supported by radiocarbon dating. Three main phases were identified in the history of the bog and surrounding woodland vegetation: 4000–400 BC, 400 BC–AD 1700 and AD 1700–2011. Except for terrestrialisation and the fen-to-bog transition phase, the development of bog vegetation was mainly dependent on the climate until approximately AD 1700. The dominant taxon in Gązwa bog was Sphagnum fuscum/rubellum. Woodland development was significantly affected by human activity at several time periods. The most visible human activity, manifested by the decline of deciduous species, occurred ca. 350 BC, ca. AD 250, ca. AD 1350 and after AD 1700. These events correspond to phases of human settlement in the area. During 400–300 BC, the decline of deciduous trees, primarily Carpinus, coincided with an increase in indicators of human activity and fire frequency. At ca. AD 200, Carpinus and Tilia abundance decreased, corresponding to an increased importance of cereals (Secale and Triticum). Since ca. AD 1350, the impact of Teutonic settlement is apparent, and after AD 1700, deciduous forests largely disappeared.

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Cyclones, which develop over the western Mediterranean and move northeastward are a major source of extreme weather and known to be responsible for heavy precipitation over the northern side of the Alpine range and Central Europe. As the relevant processes triggering these so-called Vb events and their impact on extreme precipitation are not yet fully understood, this study focuses on gaining insight into the dynamics of past events. For this, a cyclone detection and tracking tool is applied to the ERA-Interim reanalysis (1979–2013) to identify prominent Vb situations. Precipitation in the ERA-Interim and the E-OBS data sets is used to evaluate case-to-case precipitation amounts and to assess consistency between the two data sets. Both data sets exhibit high variability in precipitation amounts among different Vb events. While only 23 % of all Vb events are associated with extreme precipitation, around 15 % of all extreme precipitation days (99 percentile) over the northern Alpine region and Central Europe are induced by Vb events, although Vb cyclones are rare events (2.3 per year). To obtain a better understanding of the variability within Vb events, the analysis of the 10 heaviest and lowest precipitation Vb events reveals noticeable differences in the state of the atmosphere. These differences are most pronounced in the geopotential height and potential vorticity field, indicating a much stronger cyclone for heavy precipitation events. The related differences in wind direction are responsible for the moisture transport around the Alps and the orographical lifting along the northern slopes of the Alps. These effects are the main reasons for a disastrous outcome of Vb events, and consequently are absent in the Vb events associated with low precipitation. Hence, our results point out that heavy precipitation related to Vb events is mainly related to large-scale dynamics rather than to thermodynamic processes.

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Throughout the last millennium, mankind was affected by prolonged deviations from the climate mean state. While periods like the Maunder Minimum in the 17th century have been assessed in greater detail, earlier cold periods such as the 15th century received much less attention due to the sparse information available. Based on new evidence from different sources ranging from proxy archives to model simulations, it is now possible to provide an end-to-end assessment about the climate state during an exceptionally cold period in the 15th century, the role of internal, unforced climate variability and external forcing in shaping these extreme climatic conditions, and the impacts on and responses of the medieval society in Central Europe. Climate reconstructions from a multitude of natural and human archives indicate that, during winter, the period of the early Spörer Minimum (1431–1440 CE) was the coldest decade in Central Europe in the 15th century. The particularly cold winters and normal but wet summers resulted in a strong seasonal cycle that challenged food production and led to increasing food prices, a subsistence crisis, and a famine in parts of Europe. As a consequence, authorities implemented adaptation measures, such as the installation of grain storage capacities, in order to be prepared for future events. The 15th century is characterised by a grand solar minimum and enhanced volcanic activity, which both imply a reduction of seasonality. Climate model simulations show that periods with cold winters and strong seasonality are associated with internal climate variability rather than external forcing. Accordingly, it is hypothesised that the reconstructed extreme climatic conditions during this decade occurred by chance and in relation to the partly chaotic, internal variability within the climate system.

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Background Forced displacement related to persecution and violent conflict has reached a new peak in recent years. The primary aim of this study is to provide an initial overview of the acute and chronic health care problems of asylum seekers from the Middle East, with special emphasis on asylum seekers from Syria. Methods Our retrospective data analysis comprised adult patients presenting to our emergency department between 01.11.2011 and 30.06.2014 with the official resident status of an “asylum seeker” or “refugee” from the Middle East. Results In total, 880 patients were included in the study. Of these, 625 (71.0%) were male and 255 (29.0%) female. The median age was 34 (range 16–84). 222 (25.2%) of our patients were from Syria. The most common reason for presentation was surgical (381, 43.3%), followed by medical (321, 36.5%) and psychiatric (137, 15.6%). In patients with surgical presentations, trauma-related problems were most common (n = 196, 50.6%). Within the group of patients with medical presentation, acute infectious diseases were most common (n = 141, 43.9%), followed by neurological problems (n = 70, 21.8%) and gastrointestinal problems (n = 47, 14.6%). There were no differences between Syrian and non-Syrian refugees concerning surgical or medical admissions. The most common chronic disorder of unclear significance was chronic gastrointestinal problems (n = 132, 15%), followed by chronic musculoskeletal problems (n = 108, 12.3%) and chronic headaches (n = 78, 8.9%). Patients from Syria were significantly younger and more often suffered from a post-traumatic stress disorder than patients of other nationalities (p<0.0001, and p = 0.05, respectively). Conclusion Overall a remarkable number of our very young group of patients suffered from psychiatric disorders and unspecified somatic symptoms. Asylum seekers should be carefully evaluated when presenting to a medical facility and physicians should be aware of the high incidence of unspecified somatic symptoms in this patient population.In general, there is no major difference between asylum seekers from Syria when compared to other nationalities of asylum seekers from the Middle East.

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Puumala virus (PUUV) is one of the predominant hantavirus species in Europe causing mild to moderate cases of haemorrhagic fever with renal syndrome. Parts of Lower Saxony in north-western Germany are endemic for PUUV infections. In this study, the complete PUUV genome sequence of a bank vole-derived tissue sample from the 2007 outbreak was determined by a combined primer-walking and RNA ligation strategy. The S, M and L genome segments were 1,828, 3,680 and 6,550 nucleotides in length, respectively. Sliding-window analyses of the nucleotide sequences of all available complete PUUV genomes indicated a non-homogenous distribution of variability with hypervariable regions located at the 3′-ends of the S and M segments. The overall similarity of the coding genome regions to the other PUUV strains ranged between 80.1 and 84.7 % at the level of the nucleotide sequence and between 89.5 and 98.1 % for the deduced amino acid sequences. In comparison to the phylogenetic trees of the complete coding sequences, trees based on partial segments revealed a general drop in phylogenetic support and a lower resolution. The Astrup strain S and M segment sequences showed the highest similarity to sequences of strains from geographically close sites in the Osnabrück Hills region. In conclusion, a primer-walking-mediated strategy resulted in the determination of the first complete nucleotide sequence of a PUUV strain from Central Europe. Different levels of variability along the genome provide the opportunity to choose regions for analyses according to the particular research question, e.g., large-scale phylogenetics or within-host evolution.

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68 lakes (63 Swiss, 2 French and 3 Italian) located in an altitudinal range between 334 and 2339m spanning a wide range of land-use have been investigated. The aim of the study was to discuss influences of geographic location, vegetation and land-use in the catchment area on the water and sediment chemistry of small lakes. Detailed quantitative description of land-use, vegetation, and climate in the watershed of all lakes was established. Surface and bottom water samples collected from each lake were analyzed for major ions and nutrients. Correlations were interpreted using linear regression analysis. Chemical parameters of water and sediment reflect the characteristics of the catchment areas. All lakes were alkaline since they were situated on calcareous bedrock. Concentrations of nitrogen and phosphorus strongly increase with increasing agricultural land-use. Na and K, however, are positively correlated with the amount of urbanization within the catchment area. These elements as well as dissolved organic carbon (DOC), Mg, Ca, and alkalinity, increase when the catchment is urbanized or used for agriculture. Total nitrogen and organic carbon in the sediments decrease distinctly if large parts of the catchment consist of bare land. No correlations between sediment composition and maximum water depth or altitude of the lakes were found.¶Striking differences in the water compositions of lakes above and below approximately 700 m of altitude were observed. Concentrations of total nitrogen and nitrate, total phosphorus, DOC, Na, K, Mg, Ca, and alkalinity are distinctly higher in most lakes below 700 m than above, and the pH of the bottom waters of these lakes is generally lower. Estimates of total nitrogen concentrations, even in remote areas, indicate that precipitation is responsible for increased background concentrations. At lower altitudes nitrogen concentrations in lakes is explained by the nitrogen loaded rain from urban areas deposited on the catchment, and with high percentages of agricultural land-use in the watershed.

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Continental climate evolution of Central Europe has been reconstructed quantitatively for the last 45 million years providing inferred data on mean annual temperature and precipitation, and winter and summer temperatures. Although some regional effects occur, the European Cenozoic continental climate record correlates well with the global oxygen isotope record from marine environments. During the last 45 million years, continental cooling is especially pronounced for inferred winter temperatures but hardly observable from summer temperatures. Correspondingly, Cenozoic cooling in Central Europe is directly associated with an increase of seasonality. In contrast, inferred Cenozoic mean annual precipitation remained relatively stable, indicating the importance of latent heat transport throughout the Cenozoic. Moreover, our data support the concept that changes in atmospheric CO2 concentrations, although linked to climate changes, were not the major driving force of Cenozoic cooling.

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This layer is a georeferenced raster image of the historic paper map entitled: Routes des postes et des voitures pour les marchandises et pour les voyages par l'Empire dans les principaux Etats de l'Europe, T. Stemmers, sculp. It was published by chez Reinier & Iosue Ottens, between 1730 and 1739. Scale [ca. 1:2,500,000]. Covers the Central Europe region. Map in French. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Europe Lambert Conformal Conic coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, territorial and administrative boundaries, shoreline features, and more. Relief shown pictorially. Depths shown by shading.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

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This layer is a georeferenced raster image of the historic paper map entitled: Deutschland und der gröste Theil der umliegenden Staaten : oder Mittel-Europa in 35 Blättern : nach astronomischen Ortsbestimmungen und den besten Special-Karten, mit Rücksicht auf die neuesten Grenz-Bestimmungen entworfen, zufolge der Wiener Congress-Akte, des Pariser Friedens vom 21ten Nov. 1815, und der neuesten Austauschungen 1816, von H.H. Gotthold ; geschrieben und gestochen von H. Kliewer ; sämtliche Gebürge im Atlas sind gezeichnet und gestochen von Paulus Schmidt, so wie auch die Sectionen 3,11,16,18,19,21,25,26,31 von demselben gestochen worden. It was published by Simon Schropp & Co., ca. 1816. Scale [ca. 1:1,100,000]. Covers the Central Europe region. Map in German. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Europe Lambert Conformal Conic coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, ground cover, territorial boundaries, shoreline features, and more. Relief shown by hachures. Depths shown by shading. Includes also inset index map.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

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This layer is a georeferenced raster image of the historic paper map entitled: Neueste Eisenbahn-Karte von Central-Europa : mit genauer Angabe aller Stationen und den influirenden Post-Verbindungen, nach dem neuesten und zuverlässigsten Quellen bearbeitet von U. Hendschel. It was published by Carl Jügel's Verlag in 1859. Scale 1:1,900,000. Covers the Central Europe region. Map in German.The image inside the map neatline is georeferenced to the surface of the earth and fit to the Europe Lambert Conformal Conic coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, railroads, territorial and administrative boundaries, shoreline features, and more. Relief shown by hachures. Includes also scale comparison chart and index of political units.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

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This layer is a georeferenced raster image of the historic paper map entitled: Neueste Eisenbahn-Karte von Central-Europa : mit genauer Angabe aller Stationen und den influirenden Post-Verbindungen, nach dem neuesten und zuverlässigsten Quellen bearbeitet von U. Hendschel. It was published by Carl Jügel's Verlag in 1872. Scale 1:1,900,000. Covers the Central Europe region. Map in German. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Europe Lambert Conformal Conic coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, railroads, territorial and administrative boundaries, shoreline features, and more. Relief shown by hachures. Includes also scale comparison chart and index of political units.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

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This layer is a georeferenced raster image of the historic paper map entitled: L'Empire d'Allemagne, divisé en tous ses estats : a l'usage de Monseigneur Le Duc De Bourgogne = Nova Imperii Germanici descriptio, in omnes suos circulos, electoratus, &c divisi : ad usum serenissimi Burgundiae Ducis, par ... H. Iaillot. It was published by H. Jaillot in 1695. Scale [ca. 1:2,400,000]. Covers the Central Europe region. Map in French and Latin. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Europe Lambert Conformal Conic coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, territorial and administrative boundaries, shoreline features, and more. Relief shown pictorially.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.