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1.
The Baltic Sea, particularly its southeastern part, is discussed in the paper. Investigations of regional character as well as specialized studies in the area are reviewed. General historical works are mentioned briefly. Previous surveys since the 1950s are presented by the subject studied. The compilation of geological structure of the SE Baltic Sea bottom and adjacent land of Balticum (Baltic States: Estonia, Latvia, Lithuania) is based on considerable amounts of summarized materials. The crystalline basement, sedimentary cover and Quaternary deposits are characterized in the comprehensive survey of geological structure. From a stratigraphical point of view, geological sequence of the platformal cover is comparatively complete: deposits of all geological systems (from the Archean to Cenozoic) are present in the Baltic Syneclise. Considering geotectonical cycles, the sedimentary cover of the syneclise is subdivided into four structural complexes. The thickness and distribution of Quaternary deposits are closely related to the recent bottom relief of the Baltic Sea that in turn is inherited from the Pre-Quaternary surface. Buried palaeo-valleys are characteristic of the Pre-Quaternary surface in the Baltic region and the Baltic Sea bottom. The Quaternary is characterized by layers of various geneses and by sharp changes of their thicknesses.  相似文献   

2.
In the Baltic countries — Estonia, Latvia and Lithuania — groundwater is the principal and only source of clean drinking water. Its safe yield is rather large — 6.7 mln m3/d. At present, consumption does not reach half of this amount. Therefore, the resources available will be sufficient for a rather remote future, provided that groundwater is not polluted. Under Soviet rule, insufficient attention was paid to ecological problems in the Baltic States. As a result, due to constantly increasing surface pollution, groundwater quality is decreasing. The topmost, unconfined aquifer is unfit for use, especially in many urbanized areas. Moreover, pollutants, especially organics, are starting to enter the lower, artesian aquifers. To determine and forecast groundwater quality, a monitoring system has been worked out. However, in order to protect groundwater, besides monitoring, new laws, regulations, and guarantees for their implementation are necessary.  相似文献   

3.
E. V. Bunkše 《GeoJournal》1992,26(2):203-209
The dominant element in Latvian culture is nature rather than history. Latvians are as bound to place, to landscape, to particular geographies, as other peoples are bound to tribal legends and religions. Incorporation of this Baltic land into the Soviet Union in 1940 occasioned dramatic conflicts between these deeply-rooted orientations to the concrete facts of nature and the abstract formulations of Marxism-Leninism. The nature culture of Latvia, celebrated in daina, folk arts and crafts, is the bedrock on which the current independence movement has been built. Two major challenges are being addressed: the overt political one between Moscow center and the Baltic republics, and a deep intellectual conflict between the closed ideology of Marxism-Leninism and the open-ended nature and place-oriented cultures of the Baltic peoples.  相似文献   

4.
The Quaternary glacial sequences in the Baltic region in Estonia. Latvia and Lithuania are relatively complete and reasonably well studied. The maximum thickness of deposits (200 300 m) is found in the uplands and ancient valleys. Tills of several genetic types have been described and in this paper the present view on the structure of the Pleistocene cover is given. The ice movement and glacial sedimentation were controlled by climate. underlying topography and tectonic processes.  相似文献   

5.
A database consisting of radiocarbon (14C), optically stimulated luminescence (OSL), thermoluminescence (TL) and beryllium (10Be) dates was used for timing the advance of the Late Weichselian Scandinavian Ice Sheet (SIS), determining the age of the Last Glacial Maximum (LGM) and the rate of deglaciation. The study area encompasses the southeastern sector of the last SIS between the Baltic Sea and the LGM position in the western part of the East European Plain, covering the Karelian Ice‐Stream Complex (ISC) area in the east and the Baltic ISC area in the west. The linear advance and recession rates of the last SIS were estimated to be between 110 and 330 m a?1 and between 50 and 170 m a?1, respectively. The onset of the last SIS in the Karelian ISC area reached the western shores of Latvia not before 26 OSL ka, and in the Baltic ISC area, on the southern shores of the Gulf of Finland, not before 21 OSL ka. The last SIS reached close to the LGM position earliest in NW Belarus, not earlier than 22.6 cal. 14C ka BP, and latest in the NE of Belarus, not earlier than 19.1 cal. 14C ka BP. The Baltic ISC area between the LGM position and the western shores of Latvia was deglaciated in about 8 ka, and in the Karelian ISC area, between the LGM position and the southern shores of the Gulf of Finland, in about 2.6 ka. The whole area between the LGM position and the Baltic Sea was deglaciated between 14.2 10Be ka and 13.3 cal. 14C ka BP.  相似文献   

6.
Atmospheric pollution in the Baltic countries of Estonia, Latvia, and Lithuania has been mapped using measurements of pollutant concentrations in mosses, topsoil and precipitation. Air masses from western Europe deposit industrial pollutants in the Baltic region and concentrations depend on meteorological conditions. Superimposed on this background is the pattern of deposits from local sources. Large areas receive neutral to basic precipitation due to cement industries and fly ash emissions from fossil fuel combustion. The burning of oil-shale in NE Estonia results in precipitation with pH values over 7.0, and high concentrations of V, Fe, and Cd. Heavy metal concentrations in the topsoil around large cities indicate ecologically unsound city planning and insufficient control of pollutants. The Chernobyl effect in the form of radioactive deposition depended on rainfall events during the accident.  相似文献   

7.
Lin  Jan  Robinson  Paul 《GeoJournal》2005,64(1):51-61
Suburban Chinatowns are intriguing subjects for study and comparison. These ethnic suburbs, or ethnoburbs, have emerged to coexist or compete with the older downtown Chinatowns traditionally found in American central cities. Their growth since the 1960s challenges many traditional assumptions regarding the spatial and cultural assimilation of immigrants in U.S. society, namely that ethnicity would decline with the geographic and socioeconomic mobility of immigrants from the inner city into the suburbs. We examined recent growth trends in the Chinese ethnoburb of the San Gabriel Valley region of Greater Los Angeles, through analysis and mapping of U.S. Census data, and discovered ethnic persistence rather than spatial and cultural assimilation. We also discovered the ethnoburb is differentiated between a lower-class core and two middle-to-upper class fringe districts. Though there is some linguistic assimilation on the northwest fringe, the majority of the ethnoburban population continues to speak Chinese. Linguistic isolation is not a barrier to achieving a higher socioeconomic class position in the Chinese ethnoburb of Los Angeles. An earlier version of this paper was presented at the American Sociological Association Annual Meeting, San Francisco, California, August 2004.  相似文献   

8.
Heikkilä, M. & Seppä, H. 2010: Holocene climate dynamics in Latvia, eastern Baltic region: a pollen‐based summer temperature reconstruction and regional comparison. Boreas, Vol. 39, pp. 705–719. 10.1111/j.1502‐3885.2010.00164.x. ISSN 0300‐9483. A pollen‐based summer temperature (Tsummer) reconstruction reveals the Holocene climate history in southeastern Latvia and contributes to the limited understanding of past climate behaviour in the eastern sector of northern Europe. Notably, steady climate warming of the early Holocene was interrupted c. 8350–8150 cal. yr BP by the well‐known 8.2 ka cold event, recorded as a decrease of 0.9 to 1.8 °C in Tsummer. During the Holocene Thermal Maximum, c. 8000–4000 cal. yr BP, the reconstructed summer temperature was ~2.5–3.5 °C higher than the modern reconstructed value, and subsequently declined towards present‐day values. Comparison of the current reconstruction with other pollen‐based reconstructions in northern Europe shows that the 8.2 ka event is particularly clearly reflected in the Baltic region, possibly as a result of distinct climatic and ecological gradients and the sensitivity of the vegetation growth pattern to seasonal temperature change. The new reconstruction also reveals that the Holocene Thermal Maximum was warmer in Latvia than in central Europe and Fennoscandia. In fact, a gradient of increasing positive temperature anomalies is detected from northernmost Fennoscandia towards the south and from the Atlantic coast in Norway towards the continental East European Plain. The dynamics of the temperate broadleaved tree species Tilia and Quercus in Latvia and adjacent northern Europe during the mid‐Holocene give complementary information on the multifaceted climatic and environmental changes in the region.  相似文献   

9.
A GIS-based palaeogeographic reconstruction of the development of the Baltic Ice Lake (BIL) in the eastern Baltic during the deglaciation of the Scandinavian Ice Sheet is presented. A Late Glacial shoreline database containing more than 1000 sites from Finland, NW Russia, Estonia, Latvia and modern digital terrain models were used for palaeoreconstructions. The BIL occupied five different levels, represented by 492 shoreline features. The study shows that at about 13.3 cal. ka BP the BIL extended to the ice-free areas of Latvia, Estonia and NW Russia, represented by the highest shoreline in this region. Reconstructions demonstrate that BIL initially had the same water level as the Glacial Lakes Peipsi and Võrtsjärv, because these water bodies were connected via strait systems in central Estonia. These strait systems were closed at about 12.8–11.7 cal. ka BP prior to the final drainage of the BIL due to isostatic uplift. Glacial Lake Võrtsjärv was isolated from the BIL at about 12.4–12.0 cal. ka BP. Exact timing of Glacial Lake Peipsi isolation is not clear, but according to the altitude of the threshold in northeast Estonia and shore displacement data it was completed at about 12.4–11.7 cal. ka BP.  相似文献   

10.
A total of 45 subfossil reindeer (Rangifer tarandus) antlers and bones - artefacts excluded - have been found over the years in the Baltic countries of Estonia, Latvia and Lithuania. The relatively high number of specimens suggests a stable residence of the species in the eastern Baltic region. For the first time, 12 of these finds were radiocarbon-dated. The ages of the samples range between 12 085 and 9970 14C yr BP (14 180-11 280 cal. yr BP), and cover the Lateglacial and early Holocene, a time period during which climatic conditions shifted from periglacial to temperate. The dates suggest a rapid colonization of the area during the deglaciation period and a local extinction around the Pleistocene-Holocene boundary. The results of the study do not support the theory that the recent wild reindeer populations of northern Europe had their origin in the Late Weichselian reindeer populations of the eastern Baltic region.  相似文献   

11.
The dispersion of fundamental-mode Rayleigh waves for several paths in Fennoscandia is consistent with the geological setting for the Baltic shield. Additional dispersion data indicate that the Barents Sea is a shield as well. The dispersion under the Baltic Sea is similar to the north-central United States, suggesting the extension of the mantle shield structure beneath the continental Paleozoic sedimentary cover.  相似文献   

12.
A statistical downscaling approach is applied to the output of five different global climate model simulations driven by twenty-first century future scenarios of greenhouse gas concentrations. The contribution of sea-level pressure (SLP) and precipitation changes to regional future winter sea-level changes is estimated for four Baltic sea-level stations by establishing statistical relationships between sea level as predictand and large-scale climate fields as predictors. Using SLP as predictor for the central and eastern Baltic Sea level stations, three climate models lead to statistically significant twenty-first century future trends in the range of the order of 1–2 mm/year. Using precipitation as predictor for the stations in the southern Baltic coast all five models lead to statistically significant trends with a range of the order of 0.4 mm/year. These numbers are smaller, but of the order of magnitude as the predicted global sea-level rise.  相似文献   

13.
Explaining divided cities in China   总被引:1,自引:0,他引:1  
Explanations of the existence of socio-spatial divisions in Western Europe and the United States revolve around the importance of economic, demographic, political, and socio-cultural macro developments and often also on the role of globalization. Much of the literature also emphasizes the role of institutions, especially the national and local state as well as individual and household constraints and opportunities. Many authors explain socio-spatial divisions by a mix of these factors and developments. This paper provides an account of the current state of affairs concerning the literature and theory on divided cities in China. Concentrating on a selection of 88 articles published in international journals during the last decade, we examine how authors explain urban socio-spatial divisions in Chinese cities. The paper indicates that a five-category framework of trends, policies, players, position, and preferences are useful in addressing the complexity of explanations attributed to current urban divisions and inequalities in Chinese cities. While the spatial patterns in the Western and Chinese contexts share rather similar characteristics, the interplay of mechanisms is significantly different. The influence of the state, its institutions, and the cultural background has a much stronger explanatory power in China than in the West.  相似文献   

14.
Ethnic enterprises are growing rapidly in urban areas across the United States. Anecdotal evidence from around the country reports many success stories of how ethnic businesses transform communities; however, researchers have not provided a systematic review of the role of ethnic businesses in community developing. In practice, ethnic businesses have not been formally incorporated in local planning and development process. This article provides a systematic review of the multi-faceted ways ethnic businesses contribute to community building and neighborhood development. In addition to surveying the current literature, we also chose three communities for a focused review: Buford Highway in Atlanta, Monterey Park in Los Angeles, and Sunset Park in New York. A framework is developed to evaluate the economic, physical, social/cultural, and political effects that ethnic businesses exert on communities. We find that ethnic businesses can serve local economic interests and community-level cohesion and accrue economic, social, physical, and political benefits to their respective communities. These include serving the unmet market needs of certain neighborhoods and households, creating job opportunities and generating revenues, revitalizing and fueling the commercial development of abandoned communities, organizing and promoting social life and cultural diversity, as well as contributing their collective interest and voice in local communities. We argue that ethnic businesses should be better incorporated into urban policies in community economic development.  相似文献   

15.
Qingfang Wang  Wei Li 《GeoJournal》2007,68(2-3):167-182
Previous research suggests that entrepreneurship can provide ethnic minorities a springboard for economic advancement and social integration. However, self-employment rates vary significantly among ethnic groups, between men and women, and in different places. The prevailing literature suggests that personal characteristics, including human capital attributes, ethnic networking, institutional regulations, societal structures and discrimination, all contribute to the differential ethnic entrepreneurship rates. However, very few recent studies have analyzed how different urban socio-economic contexts influence this process. Using the 2000 Public Usable Microdata Samples (PUMS), this study examines how Hispanic entrepreneurs perform in three different metropolitan areas in the US South. The results show that the ethnic diversity, history of immigration, and the economic structure in each local area have provided different opportunities and challenges for Hispanics to start up and maintain their own businesses. This study suggests that the process of economic incorporation of ethnic minorities and immigrants depends significantly on the institutional capacity and social, cultural and political resources of local communities.  相似文献   

16.
Dear and others associated with the ‘Los Angeles School of Urbanism’ have presented a series of challenging ideas regarding changes in urban form as a consequence of the shift from modernism to post-modernism. Some of those challenges relate to a city’s ethnic diversity and residential segregation, with Los Angeles presented as a paradigm exemplar of an emerging new urban form. This paper evaluates the arguments that Los Angeles in particular, and Californian metropolitan areas more generally, differ from metropolitan areas elsewhere in the United States in the nature of ethnic residential segregation there. Regression analyses provide little support for the argument, but graphical analyses show that although Los Angeles does not differ from the general, US-wide trends, its almost unique nature in terms of its ethnic diversity means that it clearly stands out as a place with a different pattern shared by very few others.  相似文献   

17.
Estonia may be taken as an example of how cartography has developed in the national languages of the Baltic States. Late in the 17th century the first survey of Estonian and Latvian territories was carried out by the Swedes. Masterpieces of the 18th century and the first half of the 19th century are the Atlas of Livonia by L. A. Mellin and a special map of Livonia by C. G. Rücker. The first maps in Estonian appeared more than one hundred years ago. The short period of independence, 1918–1940, was one of rapid development in cartography, interrupted by occupation of the Baltic States by the USSR. Maps were destroyed or declared secret; use of maps was limited. From the beginning of the 1990s, a rapid renaissance of national cartography began.  相似文献   

18.
The occurrence of seals in the Finnish prehistoric fauna and in the Baltic since the end of the last glaciation is discussed on the basis of subfossil remains in refuses at cultural sites, and stray finds. The species represented are the harp ( Phoca groenlandica Müller), the ringed seal ( Phoca hispida Schreb.), and the grey seal ( Halicoerus grypus (Fabr.)), of which the latter two are native in the recent fauna, whereas the former has since become extinct in the Baltic. The earliest seals, which probably immigrated to the Yoldia Sea, were ringed seals, whereas the subfossil harp seals are solely found in sediments of the Litorina Sea stage.  相似文献   

19.
Doumenge JP 《GeoJournal》1988,16(2):143-156
Demographic, sociocultural, economic, and political trends in the French islands of the South Pacific are examined. Consideration is given to population distribution, internal and interisland migration, economical assets and weaknesses, political relationship with France, and cultural traditions unique to New Caledonia, French Polynesia, and Wallis and Futuna Islands.  相似文献   

20.
The study investigates the mechanism of glacial meltwater recharge under the Fennosciandian Ice Sheet during the last glacial maximum (LGM) and its impact on regional groundwater flow in the northern Baltic Artesian Basin (BAB) in Estonia and Latvia. The current hypothesis is that a flow reversal occurred in the BAB due to subglacial recharge during the LGM. This hypothesis is supported by an extensive dataset of geochemical and isotopic measurements in the groundwater of northern Estonia, exhibiting significant depletion in δ18O with respect to modern precipitation. To verify the consistency of this hypothesis and better understand groundwater flow dynamics during the LGM period, a numerical model is developed for this area. Two cross-sectional models have been created across the northern BAB, in which groundwater flow and the transport of δ18O have been simulated from the beginning of the LGM to present-day. Several simulations were performed with different subglacial boundary conditions, to investigate the uncertainty related to subglacial recharge of meltwater during the LGM and the subsequent flow reversal in the northern BAB. Several simulations provide a satisfying fit between computed and observed values of δ18O, which means that the hypothesis of subglacial recharge of meltwater is consistent with δ18O distribution. The numerical model suggests that preservation of meltwater in northern Estonia is controlled by confining layers and the proximity to the outcrop area of aquifers, located in the Gulf of Finland. The results also suggest that glacial meltwater has been preserved under the Baltic Sea in the Gulf of Riga.  相似文献   

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