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1.
Anton Gosar 《GeoJournal》1989,19(3):277-283
This paper outlines the structure of international tourism in Yugoslavia and then discusses thevarious impacts its development has had, notably changes in the population structure. The growth of international tourism has enabled a nontraumatic restructuring of the younger generation island and coastal population away from fishing and farming to employment in tourism. Tourism has revived some Yugoslav regions, especially the Adriatic Coast, in a demographic and economic sense and has made possible further development.  相似文献   

2.
Nature based tourism (NBT) as an effective instrument for sustainable use of biodiversity is an interesting issue to be studied in order to evaluate response the of international community to the interaction between developmental and environmental pillars of sustainable development. Various international endeavours have been carried out with considerable outcomes to address NBT in different forms and manifestations. As a result, the international community has attained many successful achievements and valuable experiences. There is an urgent need for an internationally accepted instrument to address the existing gaps and overlaps appropriately. Such an instrument should respond to lake of adequate environmental and developmental rules and regulations at international scale. Careful study of major international environmental and developmental achievements related to NBT could provide the international community with an appropriate legal framework to address such an environmentally fragile, economically viable, and a culturally sensitive issue.  相似文献   

3.
E. Bevilacqua  E. Casti 《GeoJournal》1989,19(3):285-287
The Veneto region is one of the major tourist destinations in Italy, attracting some 20 million foreign and 24 million domestic arrivals each year through the variety of natural and cultural resources it has to offer. This paper examines the structure of foreign tourism, highlighting the importance of the Adriatic coast and Venice, and outlines some of the impacts which have resulted from the rapid and unplanned development of mass tourism.  相似文献   

4.
为了探明在川东岩溶地区蓬勃兴起的休闲农业旅游活动对土壤生态环境的影响,以重庆市铜梁区黄桷门奇彩梦园(黄门现代农业园区)(下称“奇彩梦园”)和北碚区金果园(休闲观光果园)(下称“金果园”)游步道两侧的土壤样区为研究对象,通过现场调查、采样和实验室分析,研究了土壤各生态指标受影响的距离、受冲击规律及重金属潜在风险。结果表明:受农业游憩影响,两园区土壤含水量、土壤有机质、土壤全氮及碱解氮随着离游径的距离变小呈递减的趋势,土壤容重呈递增的趋势,而土壤pH值仅在奇彩梦园表现出随离游径的距离变小呈递增趋势,各指标受影响的范围主要集中在4 m内;运用践踏指数分析得出两园区处于轻度践踏状态,土壤腐殖质层和草本并没有完全破坏,土壤生态环境在自然状态下可以得到一定恢复。通过对两园区土壤重金属的评价,发现各样区土壤环境处于清洁或尚清洁状态,Cd和Pb在部分样区内含量达到安全警戒状态(污染指数>0.7),需采取措施重点防控。   相似文献   

5.
The evolution of photospheric velocities from the first minutes after the emergence of fresh magnetic flux and the formation of the first pores in active region NOAA 10488 is studied with a time resolution of 1 min and spatial resolution of 4″. The emerging magnetic flux of a major active region is initially a bundle of magnetic-flux loops. Some of these loops erupt through the system of supergranular cells with speeds of up to 1 km/s within 15–25 min and form pores and small spots. It is suggested that the development of a pore represents the emergence of a horizontal magnetic field, which is converted into elements with a strong vertical magnetic field. The region of ascending plasma initially coincides with the zero line of a bipolar magnetic pair. Downflow and upflow regions are related to and appear with the development of pores. During the first hours of their evolution, the trailing-polarity pores exhibit downflows with mean speeds of ∼500 m/s, while upflows with speeds of ∼250 m/s dominate near the leading-polarity pores. It is concluded that a matter flow from the leading to the trailing end is present in the rising loop of a magnetic flux tube, in agreement with well-known numerical-simulation results. The flow that develops in the magnetic-flux tube erupting through the convection zone persists when pores and small spots emerge in the photosphere, at least during the first hours of their evolution.  相似文献   

6.
Anticipating the scale invariance of rock fracturing processes, we applied Keilis-Borok’s algorithm M8, originally designed for identifying times of increased probability (TIPS) of occurrence of strong earthquakes (M < 8.0), retrospectively to Koyna earthquakes which occurred in the region after the impoundment of the Shivaji Sagar reservoir in 1962. The algorithm which enables diagnosis of TIPS from the 7th year onwards after the commencement of the earliest available data set showed that the 5.3 magnitude earthquake of 20 September 1980 indeed occurred within a time of increased probability. This result, apart from its potential application to recognizing future TIPS in the region, points to selfsimilarity between the premonitory patterns of natural and induced earthquakes and to scale-invariant nature of their processes. Further, a typical precursory rise in seismicity followed by a relative quiescence was also found to precede all the three larger earthquakes of the sequence.  相似文献   

7.
There is a mistaken perception of a growing trade with Russia and an increase in the amount of investment available for Western businessmen in the Federation. This article argues that in fact, there is no room for real investment in the Russian Federation, as defined in Western terms and that the nature of Russian industrial organisation is such that the military dictates the nature of all meaningful industrial production, as well as having the pick of the raw materials and the workforce. There is a growing disillusion with Western methods of management and also this has spread to treaty commitments (such as the Conventional Forces Europe (CFE)) and any attempt to exercise military restraint, because of the mockery of the Western press when such measures have been taken, as in Chechnia. Overall, the need the West has to make itself believe that the Russian Federation is rapidly becoming a new trading partner in a safer international system is fundamentally mistaken. Russia and America have the ability, should they wish or have to, to marginalise a newly united Europe. Furthermore, Russia has the ability to dominate such a European federation and to claim the status of a Regional Superpower. Without America there would be no security organisation that could resist such a claim. Russia is not as far along the road to democracy as hard-pressed Western governments need to claim, so that they may cut defence expenditure and it is dangerous to pretend that the Russian Federation is capable of exporting much more than aggression. The West may well be spending money which it claims is part of planned investment in Russia, to simply buy off the aggressor state Russia has rapidly become, for another few months.  相似文献   

8.
满发胜 《矿床地质》1985,4(1):47-53
近年来,人们利用岩石中稀土元素(REE)分布模式,在区分岩石类型、探讨岩石的成因、物质来源及演化历史等问题上积累了许多资料。作者对我国华南地区几个与钨矿有成因联系的花岗岩类岩体进行了系统的稀土元素分析;并根据所获得的稀土模式特征,结合野外地质观察和同位素地质研究成果,对其岩石类型、成因及物质来源等问题进行了讨论。其目的在于为该类型钨矿的找矿和成因理论研究提供佐证。  相似文献   

9.
When Czechoslovakia was formed after World War I from the remains of the Austro-Hungarian Empire, the national boundaries imposed at the time did not accurately portray the areal extent of some ethnic groups. This was particularly true for the Hungarian minority which was established along the southern border of Slovakia. Because of this boundary arrangement, ethnic and economic divisions have resulted within Czechoslovakia and have continued in the new state of Slovakia. This paper analyzes the contemporary regional extent of the major ethnic groups in Slovakia at the district and commune levels. It also analyzes these ethnic patterns in light of a number of economic characteristics. Methods include mapping and analysis of various statistical tests using 1991 Czechoslovak census data. A strong relationship between Hungarian communes and agricultural employment is shown as well as a connection between employment in industry and Slovak ethnic regions. These findings suggest that the Hungarian minority has experienced a substantial geopolitical shift from the group in power to a peripheral society within Slovakia that continues to exhibit higher levels of agricultural reliance than the majority of ethnic Slovakian regions.  相似文献   

10.
The six international geological reference materials of South African origin have been analysed for their rare-earth content using the technique of ion exchange, combined with spark-source mass spectrography. The precision and accuracy of the results are discussed. The value of presenting the results normalized to a chondritic-based material is demonstrated.  相似文献   

11.
The coalification pattern of the Pittsburgh coal as established by isoreflectance contours has an overall trend which intersect with the prevailing structural trend of the Dunkard basin. Reflectance values increase from 0.53% in southeastern Ohio to 1.57% in the Maryland panhandle. Divergences of the reflectance contour pattern from the overall trend coincide in part with the present areas of high geothermal gradient. Crustal radiogenic heat, or regional geothermal heating, was probably the dominant heat source responsible for the coalification of the Pittsburgh coal in the Dunkard basin.A time-temperature, Lopatin-type diagram, which was constructed for the Dunkard basin near Wheeling, West Virginia, delineates conditions on maturation of sediments and provides clues to the times of petroleum migration and to the possible source beds. Silurian strata matured during subsidence and burial prior to the orogeny. The Mississippian and Pennsylvanian strata matured during or after the orogeny. The Pennsylvanian strata west of the Dunkard basin, as suggested by vitrinite reflectance values, are apparently still immature.  相似文献   

12.
Urban tourism is a focus of vibrant research in developed countries. In this paper the focus is upon an element of urban tourism in a developing world city, viz., Johannesburg. Specific attention centers on an analysis of the role of small enterprise development in urban tourism. The major issues surrounding the development of small tourism businesses in two of Johannesburg's former black townships, namely Soweto and Alexandra, which are emerging as centers for so-termed ‘township tourism’ in South Africa, are investigated. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
When Britain assumed responsibility for the French Colonies in North America (1763) the French (francophones) were concentrated in the St. Lawrence Lowlands. Subsequent settlements by British and American colonists (anglophones) were guided by government policy, economic opportunities, and political events. The outcome was a mixture of anglophone settlers initially, as intended, developing around the lowland French but subsequently evolving to a peripheral location. Crowded conditions forced the francophones to move into this peripheral area as well. Through these processes a cultural zone of transition evolved between Quebec and her neighbouring provinces. Contact between the two ethnic groups within this zone, however, has not led to integration but moreso to a cultural division. In this situation it has been generally the francophone who has accommodated to the anglophone for required social and vocational interaction. Through the application of the index of language intensity assessment of the impact of recent sociopolitical policies upon this traditional pattern has been made. In the past decade anglophones have been leaving Quebec at an accelerated rate. Those remaining have an opportunity to increase the processes of interaction and integration with the francophone society and, it is theorized, will do so if a negative attitude among the youth toward a future in the province can be overcome.  相似文献   

14.
With the utilization of GIS software, research is conducted on (a) the characteristics of cells, fragmentation, and patch fractal of landscape based on homogenous carbonate rocks in Guizhou; (b) causes of the formation of these characteristics. It has been found that under the influence of lithology, the landscape of the study region as a whole shows consistency, yet embodies distinct diversity inside. The consistency is embodied in the following aspects: (a) the preponderant landscape consists of bushes and small woods; (b) secondary landscape is characteristic of forests and grounds covered with grass; (c) of all the patches making up the study area small patches are in the majority, with positive-skewed distribution of patches-as a result, steep peaks are characteristic of the charts showing the distribution of patches. The factor of scale is not taken into account in the study of patches. The shapes of patches tend to be regular with strong disturbances from human activities, and consequently, the values of fractal dimensions of landscape types tend to get smaller. The fragmentation of patches is more apparent in landscape under influence of human activities than the one without these disturbances. Compared with regions characteristic of homogenous dolomite, the characteristics of homogenous limestone areas are described as follows: (a) low utilization rate of water resource; (b) uneven distribution of diversified landscape; (c) weak resistance against disturbances from human activities; (d) the continuous degradation, ever-increasing fragmentation, intensification of spatial heterogeneity, and the deteriorating stability of landscape.  相似文献   

15.
This study investigates the origin and chemical composition of the thermal waters of Platystomo and Smokovo areas in Central Greece as well as any possible relationships of them to the neighboring geothermal fields located in the south-eastern part of Sperchios basin. The correlations between different dissolved salts and the temperature indicate that the chemical composition of thermal waters are controlled by, the mineral dissolution and the temperature, the reactions due to CO2 that originates possibly by diffusion from the geothermal fields of Sperchios basin and the mixing of thermal waters with fresh groundwater from karst or shallow aquifers. Two major groups of waters are recognized on the basis of their chemistry: thermal waters of Na–HCO3–Cl type and thermal waters mixed with fresh groundwater of Ca–Mg–Na–HCO3 type. All thermal waters of the study area are considered as modified by water–rock interaction rainwater, heated in depth and mixed in some cases with fresh groundwater when arriving to the surface. Trace elements present low concentrations. Lithium content suggests discrimination between the above two groups of waters. Boron geochemistry confirms all the above remarks. Boron concentration ranges from 60 μg L?1 to 10 mg L?1, while all samples’ constant isotopic composition (δ11B ≈ 10 ‰) indicates leaching from rocks. The positive correlation between the chemical elements and the temperature clearly indicates that much of the dissolved salts are derived from water–rock interactions. The application of geothermometers suggests that the reservoir temperature is around 100–110 °C. Chalcedony temperatures are similar to the emergent temperatures and this is typical of convective waters in fault systems in normal thermal gradient areas.  相似文献   

16.
Abstract The magnitudes of plastic strains of 104 metacherts were determined from the deformed shape of initially spherical radiolarians in the Sambagawa high- P type metamorphic belt of Western Shikoku, Japan. The strain magnitude increases with increasing metamorphic temperature from several per cent to 250%. The a2/a3 ratio of strain ellipsoids in the higher metamorphic grades decreases with increasing metamorphic grade while the a1/a2 ratio increases rapidly. The long axis of the strain ellipsoid for every grade is nearly parallel to the length of the metamorphic belt, suggesting that the flow direction of the synmetamorphic deformation was uniform along the belt. A map of strain zones within the Sambagawa high- P type metamorphic belt reveals that the metamorphic belt underwent a progressive bulk inhomogeneous shear deformation and that the high-grade zones represent a deep-seated boundary shear zone on the accretionary wedge between a subducting oceanic plate and the immobile rigid continental plate.  相似文献   

17.
18.
In the developed world at least, the century-long migration towards the high density core regions is over. To establish this thesis, internal migration statistics for 22 countries are examined, covering the period 1950–1979. Of these 22 countries, five categories are distinguished: (1) the countries of north-western Europe (Belgium, Denmark, France, the Netherlands, and West Germany), in which there is moderate net out-migration from the core regions; (2) the countries of North America (Canada and the United States), in which net out-migration from the core regions has become quite substantial; (3) countries on the periphery of western Europe (Finland, Iceland, Italy, Norway, Spain, Sweden, and the United Kingdom), and including Japan and New Zealand, in which the modal pattern is one of increases in net migration towards the core regions between the 1950s and 1960s, followed by a sharp decline in the 1970s, though not to the point where a sustained net flow of population away from these regions has been observed; (4) the countries of eastern Europe (Czechoslovakia, East Germany, Hungary, and Poland), in which net migration towards the core regions, though quite moderate, has yet to show a systematic decline; and (5) two advanced developing countries in eastern Asia (South Korea and Taiwan), in which net migration towards the core regions is very large and showing no signs of imminent decline. The countries of the first three categories belong to the developed world, in which economies of further agglomeration in the core regions no longer exist, according to the hypothesis put forward in the second half of this paper. The distinguishing feature of the countries in the first two of these three categories is that their less urbanized, peripheral regions offer sites for urban and industrial development which are competitive with those of the core regions. In contrast, the peripheral regions of the countries of the third category do not offer competitive sites for industry and urban development, due to fundamental deficiencies in physical geography. Thus, despite the disappearance of the agglomeration advantages of the core regions, a sustained net flow of population away from these regions has yet to be observed. Finally, the countries of the fourth and fifth categories, according to our hypothesis, are those in which the economies of further agglomeration in the core regions are still present, due to a lower level of economic development. What distinguishes these last two categories of countries is the strong state policies of decentralization in the countries of eastern Europe, which seem to have avoided the very large and growing net flow of population towards the core regions observed for South Korea and Taiwan, where decentralization policies, though extant, are still subservient to national economic growth policies and are consequently much weaker.  相似文献   

19.
Heike C. Alberts 《GeoJournal》2007,68(2-3):141-153
In the aftermath of the terrorist attacks of September 11, 2001, newspapers and magazines reported a dramatic decline in the enrollment of international students at US universities. Many of these articles blamed this decrease on the difficulties of getting a visa to the US and expressed concern about the potential impact on the US education system and economy. A look beyond the headlines, however, reveals that this decline cannot be attributed exclusively to the heightened security measures, as student numbers from some countries had already begun to decline before 2001 or continue to increase despite the changed regulations. Therefore, other factors also play a role in explaining the diverse migration patterns—most notably increasing competition from other host countries and changing economic and educational conditions in sending countries. Since international students often stay in their host countries after the completion of their degrees, the United States has a strong interest in continuing to attract international students as potential highly skilled immigrants. In order to achieve this, changes need to be implemented at the government level as well as at individual universities.  相似文献   

20.
本文以云南省蒙自市西北勒乡碧色寨村石漠化土地为研究对象,基于主成分分析法(PCA)研究岩溶石漠化区不同土地利用方式下的土壤养分特征。结果表明:(1)研究区土壤各养分指标变异系数介于0.14~1.76,不同土地利用方式下,土壤养分状况有较大差异;(2)研究区土壤12项养分指标可归结为3个主成分,所提供的信息占全部信息的90.69%,其中PC1主要包含了全磷、有效磷、速效钾和有效锰,PC2主要综合了有机碳、全氮、全钙和有效锌,有效铁对PC3具有较大的贡献。(3)对不同用地类型土壤养分的主成分得分进行排序,由大到小依次为火龙果地>林地>封育草地>玉米地,表明植树造林及火龙果种植等方式能有效改善石漠化区的土壤养分状况。建议对样区的石漠化治理应以封山育土为前提,以生态恢复为目的,通过种植火龙果与修复林地改善样区土壤状况,逐步形成生态环境与社会经济协调发展的石漠化综合治理体系。   相似文献   

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