Limits Of Europe Research Articles

Physiological Performance of Beech (Fagus sylvatica L.) at its Southeastern Distribution Limit in Europe: Seasonal Changes in Nitrogen, Carbon and Water Balance

To assess the physiological performance of drought-sensitive European beech ( Fagus sylvatica L.) under the dry Mediterranean climate prevailing at its southeastern distribution limit in Europe, we analyzed seasonal changes in carbon, nitrogen and water balance of naturally grown adult trees. We determined the foliar C and N contents, delta13C and delta18O signatures, total soluble non-protein nitrogen compounds (TSNN) in xylem, leaves, and phloem, as well as leaf water potential and photosynthetic quantum yield in northern Greece during 2003. Tissue sampling was performed in May, July, and September, while field measurements were conducted regularly. Climatic conditions for the 2003 growing season fall within the typical range of the studied area. The N- and C-related parameters displayed distinct seasonal courses. TSNN was highest in May in all tissues, and asparagine (Asn) was then the most abundant compound. Thereafter, TSNN decreased significantly in all tissues and both its concentration and composition remained constant in July and September. In both months, glutamate (Glu) prevailed in leaves, gamma-aminobutyric acid (GABA) in phloem exudates from twigs and trunks, and arginine (Arg) in the xylem sap, where loading with amino acids was rather low during that period, amounting to only 0.8 micromol N ml-1 in September. Highest total foliar N and C contents were detected in May, and the elevated abundance of nutrients as well as an increased foliar delta13C signature at the beginning of the growing season is attributed to remobilization processes. The signatures of delta18O, quantum yield and leaf water potentials varied only slightly throughout the growing season. Although summer precipitation at the study site was considerably lower compared to what is usual for typical central European beech forests, no intensive drought responses of the physiological apparatus were detected in the studied beech trees. This suggests efficient internal regulation mechanisms, constantly ensuring a favourable physiological status under the relatively dry Mediterranean climate.

Impact of Electromagnetic Field Exposure Limits in Europe: Is the Future of Interventional MRI Safe? 1

The European Union (EU) has recently introduced a directive that aims to protect workers from adverse effects of exposure to electromagnetic fields. All countries within the EU are required to incorporate this directive into their national law by 2008. This legislation applies to all types of occupational exposure to electromagnetic fields with frequencies from 0 Hz to 300 GHz. It has dramatic implications for interventional magnetic resonance (MR) imaging, because workers who are close to the MR scanner while scanning is taking place are exposed at levels substantially above the exposure limits. This is especially the case for time-varying magnetic fields in the 110 Hz-5 kHz range, which includes the field from the imaging gradients. In this article, the scientific evidence on which the limits are based is brought into question. It is concluded that an urgent review of the directive is required and that more research, especially at MR gradient frequencies, is needed.

An overview of occupational benzene exposures and occupational exposure limits in Europe and North America

Benzene has become one of the most intensely regulated substances in the world. Its ubiquitous use as a solvent has led to many working populations being exposed; in the early days often in uncontrolled conditions, leading to high exposures. Current occupational exposures are tightly controlled and are largely confined to workers in the petrochemical industry, vehicle mechanics, firefighters, workers exposed to automobile emissions, and some other occupational groups. Typically, occupational exposure levels are currently at or below 3.25 mg/m 3 (1 ppm), and environmental exposures are typically below 50 μg/m 3 (15 ppb). Smoking remains a significant source of exposure in both occupationally and non-occupationally exposed individuals. The early experiences of high occupational exposures led to the identification of haematopoietic effects of benzene and the need for improved control and regulation. As with most occupational standards, there has been a reduction in exposure limits as effects have been identified at ever-lower levels, accompanied by a societal concern for improved standards of occupational health. In 1946, the United States occupational exposure limit for benzene, promulgated by the American Conference of Governmental Industrial Hygienists, was 325 mg/m 3 (100 ppm), but nowadays most European and North American countries have harmonised at 1.63–3.25 mg/m 3 (0.5–1 ppm). This latter figure was agreed within the European Union in 1997 and was adopted within national legislation by all Member States. The data on which this limit is set are essentially the same as those used by other standard-setting committees; this is an excellent example of how standards are set using science, pragmatism and societal values in the absence of complete information.

The effect of climate on the phenology, acorn crop and radial increment of pedunculate oak (Quercus robur) in the middle Volga region, Tatarstan, Russia

Our data, collected in the extreme east of Europe, show that a significant biological effect of climate change has been experienced even in territories where temperature increase has been the lowest. This study documents the climatic response of pedunculate oak (Quercus robur) growing near its north-eastern limits in Europe. It demonstrates the potential of oak trees in old-growth forest to act as proxy climate indicators. Many factors may influence the temporal stability of the growth-climate, acorn crop-climate and first leafing-climate relationships. Climate data, climatic fluctuations, reproduction, genetics and tree-age may relate to this instability. Our results stress that an increase in climate variability or climatic warming resulting from warmer winters or summers could affect the oak population in eastern Europe in a similar way to that in western Europe. These findings, from remnants of oak forest in the middle Volga region of Russia, allow a further understanding of how species could be affected by future climates.

Defining Greek and Turk: Uncertainties in the search for European and Muslim identities*

If accepted, Turkey would become the first EU member state with a Muslim majority. Greek objections no longer present the major barrier to Turkey's application. Mutual antagonism between Greeks and Turks, however, goes beyond politics, and has deep social, cultural and religious roots. This paper addresses the question of whether Greeks and Turks have constructed their identities by defining themselves as against each other, and whether there has been a parallel use of the Islamic constituent in Turkish identity to exclude Turkey from definitions of what it is to be European, and of the Christian constituent in Greek identity to define the furthest limits of Europe. The article concludes by assessing whether Islam poses a threat to European identity or whether it is part of the European cultural, social, political and religious experience.

Land application of sewage sludge: scientific perspectives of heavy metal loading limits in Europe and the United States

Heavy metals in sewage sludges accumulate in soils after successive sludge applications and can be toxic to plants, soil organisms, as well as humans and animals along the food chain. Because of this potential threat, many countries have set limits to the additions of metals in sludges to agricultural land, based on (i) the concentrations of metals in sludge itself, (ii) the loading, or total amount, of metal that can be added and often how quickly this can be applied, and (iii) the maximum concentrations of metals in soil which are allowed to build up after sludge applications. This review, based on regulations in the United States and some west European countries, shows that at present three basic approaches to setting limits can be distinguished: (i) a comprehensive analysis of the pathways of pollutant transfer to selected target organisms and an assessment of the likely harmful effects that metals may have on the target; (ii) setting limits consistent with the lowest observed adverse effect concentrations, which are actual cases of effects due to metals, but not necessarily derived from studies that involved land application of sewage sludge; and (iii) attempting to match the metal inputs to soil to the small losses of metals due to crop removal, soil erosion, and leaching ("metal balance approach"). These approaches are shown to result in widely different numerical limits being set for the same constituent, which is creating unease among the regulatory authorities worldwide. These differences appear to arise from at least two main sources. The first is whether, by a policy decision, zero impact is desired. This leads to very low limits, and is the philosophy behind the metal balance approach. The second is that those approaches that allow some increase in metal concentrations in soils often adopt different target organisms and these models suffer from the limited supply of relevant toxicity data, particularly information obtained from metals applied in sewage sludge. Differences in the philosophy behind environmental protection and in the choices of which organisms to protect explain the different metal limits for sewage sludge which have been adopted in the countries examined.Key words: zinc, cadmium, copper, chromium, nickel, lead, mercury, soil microbes, ecotoxicology, soil protection.

Wie christlich wird Europa sein?

Abstract The article discusses the topic- based upon the confessional situation of Common Europe- under which political conditions the historical stability ofthe profile of confessions in Europe is changing. Further on this topic is beeing discussed with regard to the cultural consequences of Christianity refering to economy, democracy and >>multiculturalism« and it is more concretely explained refering to the speciallegal order of churches. This deals with perspectives and limits of Europe in future.

"I Know Thee not, I Loathe Thy Race": Romantic Orientalism in the Eye of the Other

Napoleon's Egyptian campaign, conceived in a spirit of rivalry to British imperialism in India, extended French military ambitions beyond the limits of Europe and initiated a legacy of colonialism in Africa that would produce, among other less commendable cultural artifacts, a rich Orientalist literature, of which Flaubert's Salammbo, with its luridly sensual evocations of decadence and the corrupt grandeur of power, might be considered typical. Napoleon, too, seems to have gone to Egypt pursuing a mirage of Oriental glory that would contribute to his career as an aspirant to Empire and confer on him the status of world-historical figure that Hegel and others would later fabricate for him as the outstanding political leader of the age. The campaign itself was characterized by extremes of violence and bloodshed that surpass even the usual sanguinary passages of Napoleon's military exploits and rival the surrealistic excesses of Flaubert's novel; and the desert conditions and brutal methods of warfare taxed Napoleon's capacity for leadership. But it was an uneven contest at best, as the fully modernized French forces clashed with quasi-medieval Muslim hordes lacking arms and military discipline. Victory for the French here, as in Europe, was simply a matter of the triumph of the modern imperial nation-state, with its institutionalized techniques of political organization, over peoples still living in traditional forms of social life. Napoleon, with his talent for stage-managing political events, was

Europe—Quo Vadis?

Abstract Changes in Europe require the West to take more interest in and more responsibility for developments in Eastern Europe. Dangerous instability in that region might result from its economic decline and political disintegration contrasting with growing attraction of the Common Market for its peoples. The West's ability to influence Eastern European countries depends on their own reforms, which seem to be pointing from rather than towards socialism. Its involvement should be conditioned and targeted to specific projects, extension of exchange and selective transfer of know‐how. At the same time prospects for European reunification raise military security issues, as the Soviet approach is directed at excluding the USA. On the other hand the consolidation and redefinition of the limits of Europe requires the role of the super powers in its security system to be reassessed.

Some observations on shell-shape variation in North American populations of Nucella lapillus (L.)

This paper considers shell-shape variation in samples of the dog-whelk/dog-winkle, ucella lapillus, from the southern half of its North American range, between 41 and 46N, and compares it with the pattern seen in Europe. At the extreme southern limit of its American range, to the south of Cape Cod, the species exhibits features to be expected in an animal close to an environmental limit. It is generally rare and has a patchy distribution. There is little variation in the shell: almost all adult individuals have rather large, thick, white, elongated shells. This contrasts sharply with the situation in Portugal, at the southern limit in Europe, where the animals have small thin, coloured shells of intermediate shape. Away from the marginal situation, north of Nahant (42CN) in America, the species shows much the same range of variability in shell size, shape and colour on both sides of the Atlantic. Most populations appear to show the same pattern of shape variation in asociation with the exposure of their habitat to wave action. Animals from exposed sites tend to have shorter, squatter shells than their compatriots in shelter. However, in America as in some parts of Europe, there are occasional enclaves which do not fit the usual pattern. It is interesting to note that the form normally associated with extremely exposed shores from Brittany to Faroe in Europe is found in Atlantic Canada but is apparently absent from southern populations in both the U.S.A and the Iberian Peninsula.

The Tube-WormSpirorbis Vitreusand its Distribution in Britain

Spirorbis vitreus(Fab.), an arctic form, seems to be absent from Wales and most of England, but is generally abundant off the west coast of Scotland and also occurs in certain localities off Ireland, the Isle of Man, Cornwall and Brittany (which is probably its southern limit in Europe). Its range thus extends farthest down our western coasts, a distribution which is characteristic of various other northern and southern forms that are near the limits of their geographical ranges. Such species presumably benefit from the equable temperatures, adjoining deep water, and this winter-breeding species ofSpirorbisalso needs freedom from abrasion.The tubes of juvenileS. vitreusare very different from those of adults. The distribution of uncini on the abdomen shows a remarkable bilateral asymmetry, as inS. spirillum.

Alternating Pleistocene Morphogenetic Systems

AbstractAlternation of morphogenetic systems conditioned by wide swinging of climatic belts equatorward and poleward has been used to explain otherwise puzzling relict forms in many regions. A characteristic finely dissected landscape relief prevalent in some middle-latitude regions is in strong contrast with smoothed, coarse-textured, whalebacked, relatively featureless relief in others, notably western Europe, which are now in the humid-temperate zone. This latter is believed to be relict from the periglacial regimes of Pleistocene ice ages. In New Zealand where the former landscape type is typically developed, there has also been quite strong “periglaciation”, and in Europe running-water erosion cannot but have operated to some extent in interglacial ages. It appears that the periglacial smoothing has been pushed to the extreme limit in Europe but that its effects have been neutralized in New Zealand by the vigour of dissection in the alternating warm ages. Periglacial smothering, or “fossilization”, of fine-textured relief, which has been followed by renewed fine dissection, is very common at Wellington, New Zealand. The reasons are not clear why running water should have been (and should still be) more efficient in dissecting the New Zealand landscape than that of Europe, so that the relict periglacial landscape remains intact in the latter region.

Musical Instruments of the Early Middle Ages

THE TURMOIL caused by the migration of barbarian hordes into Europe completely annihilated the highly developed musical instruments of the ancient cultures. It is true that the finest of the stringed instruments of ancient Greece and Rome, the kithara, led a shadowy existence for some centuries in those areas of Western Europe which were still dependent on classical tradition; it is true that there is a slight connection between the organ of Franconia and the Alexandrian hydraulis; yet on the whole we can safely assert that the musical instruments of the early Middle Ages-the basis, that is to say, of the non-vocal music of modern times-had no direct connection with the instruments of ancient Greece and Rome. The Middle Ages saw a new beginning as far as musical instruments were concerned. The home of our Occidental instruments lay beyond the limits of Europe. The instruments were developed in Europe and brought to their present stage in that continent; but their roots go back to the East. We owe our modern instruments mainly to importations from Asia.