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1.
The geopolitical and socio-economic changes in East-Central Europe that started at the beginning of the 1990s has brought about a fundamental change in the status of frontier areas in this region. The paper examines the new transborder relationships as well as the conditions, forms and dynamics of integration processes on the example of Poland. It discusses some stimuli and barriers to cross-border co-operation, including the creation of new transborder institutional embeddedness (e.g. Euroregions). On the other hand, the paper stresses the role of the informal economy in the current development of border zones in East-Central Europe. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

2.
Paul L. Knox 《Geoforum》1982,13(3):245-250
A weakness of research into urban service delivery has been its ahistorical approach. Historical geographers, on the other hand, have neglected the issue of urban service delivery. This paper illustrates the influence and interaction of urbanization, professionalization and public policy on urban service delivery using the example of medical care in Britain.  相似文献   

3.
 Rock and flow parameters of three karstic-fissured-porous aquifers in the Krakow-Silesian Triassic formations were measured using various methods and compared. Though cavern and fissure porosities are shown to be very low (cavern porosity below 0.5% and fracture porosity below 0.2%), they contribute dominantly to the hydraulic conductivity (from about 1.3×10–6 to about 11×10–6 m/s). Matrix porosity (2–11%) is shown to be the main water reservoir for solute transport and the main or significant contributor to the specific yield (<2%). Though the matrix porosity is shown to be much larger than the sum of the cavern and fissure porosities, its contribution to the total hydraulic conductivity is practically negligible (hydraulic conductivity of the matrix is from about 5×10–11 m/s to about 2×10–8 m/s). On the other hand, the matrix porosity (for neglected cavern and fissure porosities) when combined with tracer ages (or mean travel times) is shown to yield proper values of the hydraulic conductivity (K) by applying the following formula: K≅(matrix porosity×mean travel distance)/(mean hydraulic gradient×mean tracer age). Confirming earlier findings of the authors, this equation is shown to be of great practical importance because matrix porosity is easily measured in the laboratory on rock samples, whereas cavern and fracture porosities usually remain unmeasurable. Received: 21 February 1997 · Accepted: 13 May 1997  相似文献   

4.
The nature and effects of the ‘inverse care law’ are discussed, and past attempts to promote an equitable distribution of medical manpower are assessed. A cognitive-behavioural approach is adopted to examine the practitioner's awareness of spatial inequalities in medical care standards and to identify the major factors underlying locational behaviour. Finally a series of space preference surfaces are constructed at both regional and intra-urban levels. It is suggested that interpretation of these surfaces in conjunction with objectively defined areas of underprovision can provide valuable guidance for future policy initiatives.  相似文献   

5.
Segregation is a central concept in the debate on urban issues, both in scientific literature and in society in general. The process of globalisation is particularly expected to increase polarisation and segregation in cities, resulting in the emergence of ‘ghettos’ or – as they are called in the Netherlands – ‘income neighbourhoods’. This paper tries to judge the situation in Dutch cities by studying changes over time; by looking at segregation within cities as well as between cities and the wider metropolitan area; and by comparing socio-economic differences with socio-cultural and socio-demographic characteristics. The analysis shows that the empirical facts are quite different from the ongoing debate. It establishes that socio-economic segregation is more moderate than segregation with respect to the other two dimensions. Contrary to suggestions from the vernacular debate, segregation within cities is scarcely increasing, but between cities and the surrounding area it is rising with respect to all three dimensions. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

6.
7.
Andrew H. Dawson 《GeoJournal》2000,50(2-3):97-100
In general, the health of Poles improved markedly in the thirty years after the Second World War, but there was some deterioration after 1989 before improvement resumed. Only in the case of cancer is there an upward trend and so Poles are now healthier than they have been at any time in the past. However there are sharp regional variations well exemplified by the incidence of tuberculosis, where there appears to be some correlation with poorer housing and atmospheric pollution. High death rates in Lodz (consistently the highest in the country at the voivodship level between 1989 and 1996), may also be linked with environmental pollution as well as the ageing of the population. Variations between town and country are small, but Poland shows up in a poor light when compared with other European countries. These are important issues for the administration and financing of the welfare services. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

8.
Geometric modeling of the geological layers in the Channel Tunnel area employed local variography and kriging for computing meaningful predictions and confidence intervals. The results were used to design the alignment of the tunnel, and tunneling was completed on March 28, 1991, 1 month ahead of the initial schedule. Data from 85 borehole pairs drilled during tunneling enable the geostatistical prediction to be compared with the reality, which is seldom possible. They fully validate the geostatistical approach.  相似文献   

9.
This article describes the well-exposed landform/sediment assemblage of a Pliocene palaeouvala and Pleistocene (Saalian) ice-pushed ridge in a large quarry in Upper Cretaceous marls near Rejowiec, eastern Poland. The site provides a rare opportunity to study the development of glacial depositional and deformational processes on morphologically and structurally variable bedrock. The internal structures of both chronostratigraphic units which comprise this assemblage provide evidence of two principal stages of deformation associated with an ice advance on a karstified foreland, each stage preceded by stabilization of the ice mass. The first deformational stage was characterized by the development of imbricate structures in outwash sediments (the initial ice-pushed ridge) and listric faults at the contact between the bedrock and palaeouvala fills (caused by an increasing ice load). Shallow subglacial folding of the proximal fan deposits, and a listric thrust which limited the extent of the ice-pushed ridge under development occurred in the second deformational stage. The data assembled indicate that the formation of push moraines (in a general sense) during ice-sheet advance is controlled by the substratum undulations. Closed depressions with loose fills in the foreland of advancing ice sheets can control the deformational style, geometry and extent (both lateral and vertical) of the push moraines.  相似文献   

10.
The crystalline basement of the Tatra Mountains in the Central Western Carpathians, forms part of the European Variscides and contains fragments of Gondwanan provenance. Metabasite rocks of MORB affinity in the Tatra Mountains are represented by two suites of amphibolites present in two metamorphic units (the Ornak and Goryczkowa Units) intercalated with metapelitic rocks. They are interpreted as relics of ocean crust, with zircon δ18OVSMOW values of 4.97–6.96‰. Zircon REE patterns suggest oxidizing to strongly oxidizing conditions in the parent mantle-derived basaltic magma. LA-MC-ICP-MS U-Pb dating of magmatic zircon cores yields a crystallization age of c. 560 Ma, with inherited components at c. 600 Ma, corresponding to the Pannotia break-up event and to the formation of the Eastern Tornquist–Paleoasian Ocean.However, the zircon rims of both suites yield evidence for two different geological histories. Zircon rims from the Ornak amphibolites record two overgrowth phases. The older rims, dated at 387 ± 8 Ma are interpreted as the result of an early stage of Variscan uplift while the younger rims dated at 342 ± 9 Ma are attributed to late Variscan collisional processes. They are characterized by high δ18OVSMOW values of 7.34–9.54‰ and are associated with migmatization related to the closure of the Rheic Ocean.Zircon rims from the Goryczkowa amphibolites yield evidence of metamorphism at 512 ± 5 Ma, subsequent Caledonian metamorphism at 447 ± 14 Ma, followed by two stages of Variscan metamorphism at 372 ± 12 Ma and 339 ± 7 Ma, the latter marking the final closure of the Rheic Ocean during late-Variscan collision.The presented data are the first direct dating of ocean crust formation in the eastern prolongation of the Tornquist Ocean, which formed a probable link to the Paleoasian Ocean.  相似文献   

11.
12.
This study deals with an issue of thermo-mechanical facies, reflecting specific thermal and mechanical properties of the subglacial environment. The main objective of this study was to develop a model of glacitectionic deformation and its sedimentary record beneath fast and slow flowing ice sheets, based on investigations conducted in Wielkopolska (west central Poland). Sedimentary structures, mainly at the contact between subglacial tills and glacifluvial sediments, were recognized to delineate typical facies associations in a Weichselian glacigenic succession. Each association was interpreted as a record of the different depositional environments related to different subglacial conditions. Those investigations suggest the substratum was composed of frozen and dry, and wet and mobile spots, and four thermo-mechanical facies were distinguished: A – is representative of slower ice flow, dry and cold subglacial conditions, where driving stresses and normal effective pressure were high; B – is also related to slow ice flow and occurrence of cold subglacial permafrost, but with little amount of unfrozen water (however, higher than in facies A), with similar physical characteristics of the ice sheet as facies A; thermo-mechanical facies C and D represent wet and warm ice sole, with low normal effective pressure and driving stresses, thus lowering sediments’ shear strength and enabling high ice-flow velocities. We suggest that these facies have specific and non-random location, thereby revealing the relationship between subglacial thermo-mechanical conditions and ice sheet dynamics. Slow moving, cold-based ice occurred along ice sheet margins and inter-stream areas, whereas fast-moving, warm-based, well-lubricated ice, was typical of the axial parts of ice streams.  相似文献   

13.
The future availability and sustainability of fresh groundwater resources in the South West district of the national capital territory (NCT) Delhi, India, have been projected. Due to a rapid decline in groundwater level and quality, the district has been required by the Government of India to regulate development of groundwater resources. Shallow groundwater is mostly saline and water resources in the area are limited. The methodology applied here involves microzonation of the district in terms of thickness of fresh groundwater and then quantification of present and future availability of freshwater in different freshwater zones, including tentative timescales. The calculation method has been aided by data on historic trends in water level at representative groundwater monitoring stations, located either in fresh groundwater zones or near to them. It is estimated that the presently available 481 million m3 of resources will be reduced to 374 million m3 by year 2007 and to 303 million m3 by the year 2012, and by the year 2022 the district will have only 176 million m3 of available fresh groundwater resources.  相似文献   

14.
The classical correlation by kossmat (1927) of the Saxothuringian belt of Germany with the West Sudetes of Poland is re-evaluated with special reference to the crystalline massifs of Munchberg and the Góry Sowie and the surrounding areas. Important common features are: Cambro-Ordovician magmatism and sedimentation; Silurian to Devonian radiolarian cherts in the low grade to unmetamorphosed units; Early Devonian (and older?) pressure-dominated metamorphism followed by rapid uplift; the incorporation of high pressure and mantle rocks; and Early Carboniferous mass flow deposits with ‘Saxothuringian’ clasts. Differing features in the West Sudetes are: tectonic contacts in and around the Góry Sowie are mostly subvertical and mainly (semi-)brittle (in contrast with subhorizontal and ductile contracts in the Münchberg); the Góry Sowie has undergone late re-equilibration of the earlier tectonic fabrics; an ophiolite juxtaposed with the Góry Sowie crystallized in (?) Devonian time and became only statically metamorphosed, as opposed to the regionally metamorphosed Cambro-Ordovician mafic rocks of the Saxothuringian belt; localized depocenters with Upper Devonian to Lower Permian elastic rocks relating to north-west trending strike-slip faults instead of the north-east trending cylindroidal foreland basin in the Saxothuringian. It is possible that the West Sudetes originated as an easterly continuation of the Saxothuringian belt, but then became involved, from the Late Devonian onwards, in a strike-slip system parallel with the margin of the East European Platform.  相似文献   

15.
According to recent geological interpretations, the border of the East-European Craton (EEC) in SE Poland is located in the NE foreland of the Holy Cross Mts. Results of gravity and magnetic anomaly interpretations presented herein confirm this. According to 3D and 2D gravity and magnetic modelling, the EEC borders the SW flank of the regional crystalline feature with increased magnetic and density properties, which occur in the SE part of the Teisseyre–Tornquist Zone (TTZ). This flank rests near a deep fracture delimiting the TTZ on SW. The feature is a cause of the regional magnetic gradient observed there. Two SE–NW belts of residual gravity anomalies (dislocations) are also identified in the magnetic gradient zone, cutting Mesozoic and Palaeozoic formations. Results of geophysical and geological investigations show the importance of this dislocation zone and confirm that it occurs in all crustal complexes and the upper mantle.  相似文献   

16.
The erosion of rocks rich in organic matter typically leads to the complete mineralization of the organic material. However, in some cases, it is re-deposited to become a part of sediments once more. This process should be considered to be a part of global carbon cycle, possibly much more significant than assumed to-date. The research presented here aims to characterize re-worked organic matter occurring in post-glacial sediments of southern part of Poland, in the Oder river valley (the Racibórz town region, Miocene, Pleistocene and Holocene age). Organic substances extracted from the sediments originated from organic matter that had resided in rocks eroded by glaciers. Sediments were sampled in two boreholes which sediments were correlated. Sediments were extracted and extracts analyzed with gas chromatography-mass spectrometry (GC-MS) to assess distributions of biomarker groups. Organic matter of selected samples was pre-concentrated and analyzed with Py/GC-MS. In the extracts several biomarker parameters of source/environment and thermal maturity were calculated. Organic substances in the investigated sediments come from variable re-deposited organic matter occurring in rocks eroded by glaciers. Three main parent types of re-deposited organic material are identified showing variable geochemical features: 1) organic matter of recent or almost recent age being the source of polar labile compounds; probably formed in situ, 2) re-deposited organic matter of the middle diagenesis showing features similar to lignites (huminite reflectance Rf ~ 0.25–0.35%) deriving from angiosperm remains, mainly monocotyledons and to the lower extend also deciduous trees, 3) re-deposited organic matter at the middle catagenesis (Rf ~ 0.65–0.75%) being the source of most of aromatic hydrocarbons and biomarkers such as steranes, hopanes of the more thermally advanced distribution type. Its geochemical properties and assumed directions of sediment transport indicate bituminous coals of Upper Silesian Coal Basin together with coaly shales as a possible source of this organic matter. Such mixed origin of organic matter caused large discrepancies in values of thermal maturity parameters depending on input from the particular sources and occurrence both geochemical biomarkers and their biochemical precursors in the same samples.  相似文献   

17.
18.
The objectives of this study are to investigate the levels of noise pollution in some hospitals in Taiwan and to study the effects of noise pollution on the physiological and psychological reactions and annoyance response of medical care staff, patients and visitors in these hospitals. An instrument for the measurement of sound level was used and a self-answered survey questionnaire on noise pollution was administered. Results showed that the daily average sound levels measured inside these hospitals during daytime were between 52.6 and 64.6 decibels. These are higher than the current daytime environmental noise limit of 50 decibels in Taiwan. Most nursing staff members expressed that “talking of visitors or patient’s family members” is the major source of noise inside the wards, whereas “talking of visitors or patient’s family members” and “children playing” are the two major noise sources outside the wards. However, most patients or visitors claimed that “doors opening or closing” and “patients moaning or crying” are the two major sources of noise inside the wards. “Footsteps,” “renovation of hospitals,” “talking of visitors or patient’s family members,” “shouting of nursing staff” and “doors opening or closing” are the five major noise sources outside the wards. To conclude, noise pollution inside and outside the wards either directly or indirectly affects, in a simultaneous manner, the subjective perception of noise, emotions, physiology and experience of noise inside and outside the wards of both the medical care staff and the patients and visitors.  相似文献   

19.
20.
Origin of the Kupferschiefer polymetallic mineralization in Poland   总被引:2,自引:0,他引:2  
The Kupferschiefer ore series, between the Lower Permian (Rotliegendes) terrestrial redbeds/volcanics and the Upper Permian (Zechstein) marine sequence, is developed as dark-grey organic matter-rich and metal sulphide-containing deposits (reduced zone) and as red-stained organic matter-depleted and iron oxide-bearing sediments (oxidized zone?=?Rote Fäule). The transition zone from oxidized to reduced rocks occurs both vertically and horizontally. This zone is characterized by sparsely disseminated remnant copper sulphides within hematite-bearing sediments, replacements of copper sulphides by iron oxides and covellite, and oxide pseudomorphs after framboidal pyrite. These textural features and copper sulphide replacements after pyrite in reduced sediments imply that the main oxide/sulphide mineralization postdated formation of an early-diagenetic pyrite. Hematite-dominated sediments locally contain enrichments of gold and PGE. The Kupferschiefer mineralization resulted from upward and laterally flowing fluids which oxidized originally pyritiferous organic matter-rich sediments to form hematitic Rote Fäule areas, and which emplaced base and noble metals into reduced sediments. It is argued that long-lived and large-scale lateral fluid flow caused the cross-cutting relationships, expansion of the hematitic alteration front, redistribution of noble metals at the outer parts of oxidized areas, and the location of copper orebodies directly above and around oxidized and gold-bearing areas. The Rote Fäule may be a guide to favourable areas for both the Cu-Ag and new Au-Pt-Pd Kupferschiefer-type deposits.  相似文献   

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