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1.
Jowett AJ 《GeoJournal》1986,12(4):349-363
Since 1949 China's population has increased by 500 million and thereby grown at an average rate of 2 % per year. Annual growth rates have varied dramatically, falling from 3.3 % in 1963 to 1.2 % in 1979 and registering a population decline of 13.5 million in the famine years of 1960/61. China's demographic disaster in 1958/61 ranks as one of the most devastating in the history of the world. Chinese leaders have oscillated between pro- and anti-natalist policies. However, in the 1970s the government launched its third, its most intensive and to date its most successful family planning programme. So succesful that the total fertility rate declined from 6.4 in 1968 to 2.2 in 1980 and the level of contraceptive use in China was raised to the levels currently experienced in the Developed World. Despite the high rate of contraceptive prevalence, induced abortion is still extensively used to prevent unplanned births. The extent to which China's birth control programme has been implemented on a voluntary, coercive or compulsory basis is open to question. A rapid increase in the age of marriage and a substantial improvement in female education have made important contributions to the decline in fertility. Large differences in fertility exist between rural and urban China, reflecting significant differences in the average age of marriage and the very marked difference in educational attainment between the cities and the countryside. Whether the government directed family planning programme or socio-economic development has had the greatest impact on the decline in fertility, is under discussion. Whatever the motive force, the pace of demographic modernisation has been impressive and by international standards China now enjoys advanced levels of demographic development at an early stage of economic development.Abbreviations CMP-SPRCP-75-114 China Mainland Press, Survey of People's Republic of China Press 1975, No. 114. - FBIS-CHI-83-112 Foreign Broadcast Information Service, Daily Report, China, 1983, No. 112. - JPRS-CPS-85-012 Joint Publications Research Service, China Report, Political, Sociological and Military Affairs, 1985, No. 12. - SWB/FE/6246/BII Summary of World Broadcast, Far East, No. 6246, section BII.  相似文献   

2.
Stanko Žuljić 《GeoJournal》1996,38(4):425-429
As of 1991, in the Republic of Croatia 16 percent of the total population was made up of national minorities. A large part of this figure consists of minrity nations who are the descendants of settlers from the era of Ottoman conquest during the sixteenth and seventeenth centuries, the Austrian colonization in the eighteenth and nineteenth centuries, and partially due to inter-republic migrations during the existence of the Yugoslav state.The most numerous national minority in 1991 were the Serbs (582,000, or 12.16% of the total population). The Serbian national minority is scattered throughout the Croatian state, so that in Croatia there is no integral Serbian ethnic territory. The other national minorities in Croatia are much smaller in number (Bosnian Muslims, 43,000; Slovenes, 22,000; Hungarians, 22,000; Italians, 21,000; Czechs, 13,000; Albanians, 12,000; etc.).The conflicts provoked by Greater Serbian politics and the wartime aggression against Croatia resulted in migrations, the consequence of which is the reduction in the number of the Serbian national minority in the Republic of Croatia.  相似文献   

3.
Erlich  E. 《Doklady Earth Sciences》2018,483(1):1485-1486
Doklady Earth Sciences - On the basis of combined analysis of data on a geological survey on a scale of 1 : 200 000 (1959–1960) and exploration works (1980–1990), it was found...  相似文献   

4.
Jowett AJ 《GeoJournal》1989,18(4):417-427
The recent publication of data from the 1982 census permits an assessment of the patterns, progress and problems of illiteracy in China. Educational progress, since the communists came to power in 1949, has been particularly impressive, especially in relation to the low levels of income within the People's Republic. Nevertheless, nearly a third of the country's population are still unable to read and write and major variations in literacy exist between the developed and less developed regions, between men and women, between the urban and rural areas, between the various age groups and among the many ethnic groups that constitute the People's Republic of China. Among the most favoured people and places, literacy rates exceed 90% but among the most disadvantaged groups, retired women in rural areas for example, levels of literacy fall below 3%. Proposed educational reforms, targeted to provide nine years of compulsory education, offer the potential for boosting literacy levels and breaking the bondage of ignorance. However, such proposals are being undermined by the recent economic reforms in rural China. By stressing the value of labour, including child labour, the agricultural responsibility system has generated a surprising decline in school attendance which may jeopardise future improvements in literacy, particularly so among the poorer people in the poorer areas of China.  相似文献   

5.
Information on fatalities from lightning strikes has been extracted from a specially compiled database on natural hazards in Australia. Records dating from 1803–1991 indicate that at least 650 persons have been killed by lightning strikes. Maps and charts show the percentages of victims with respect to age, sex, locality, activity, and other circumstances of the strike. The majority of the 650 fatalities recorded have occurred along the more populous southeastern coast. The overall death rate, from 1910–1989, is 0.08 per 100 000 population. The annual number of lightning fatalities has decreased with time, from a death rate of 0.21 in 1910–1919 to 0.01 in 1980–1989. This trend is more pronounced when population figures are taken into account. The group that has been most at risk in Australia is that of males aged 15–19, followed by males aged 20–34. The male:female ratio of victims has decreased with time but is not approaching equality, being 11.6 in 1910–1919 and 5.3 in 1980–1989. The diurnal and monthly occurrences of lightning fatalities peak at 12.00–18.00 hours and November-February respectively. About 86% of fatalities have occurred outdoors and 14% have occurred indoors. Approximately three-fifths of fatalities have been work-related, and the group of workers that has traditionally been most at risk is that of land-workers. Approximately one-fifth of fatalities have been recreation-related, although this proportion has been increasing with time. The recreational activities of water sports, golf, and cricket have had the greatest number of lightning fatalities. Comparisons are made between these data and the results of other similar studies, both in Australia and overseas.  相似文献   

6.
A flood risk model was developed for the Czech Republic to calculate the probability of insured losses from flood events. The model was GIS based, making use of a 100 m horizontal resolution DTM and a network of the major rivers in the country. A review of historical flooding was undertaken to define the worst and most widespread flood events. Synthetic flood events were generated based on a study of the spatial variation in magnitude of river flows from selected historical flood events going back to 1935. A total of 30 synthetic events were generated each providing peak flows at 25 gauging stations throughout the country. The flows were converted into flood levels using rating equations based on information provided by the Czech Hydrological and Meteorological Institute. The extent of and depth of flooding was mapped on a cell by cell basis by applying an automated procedure developed using the grid option within the Arc/Info GIS. The flood depths were combined with maps of the postal codes to define an average flood depth per post code. The model was calibrated using maps of the observed flood extents from 1997 and 2002.  相似文献   

7.
In the late 1970s, a concept of an ecological network in former Czechoslovakia, called the Territorial System of Ecological Stability (TSES) was formulated as a response to large-scale natural and semi-natural habitat fragmentation and loss. In the Czech Republic, the TSES concept is a part of the environmental legislation, namely of the act on the conservation of nature and the landscape. The whole system is the network of ecologically significant segments of landscape, efficiently distributed on the basis of functional and spatial criteria, covering biotic, hydrological, soil and relief conditions. It consists of biocentres, corridors and buffer zones. The TSES is established at three hierarchical levels: local, regional and supra-regional (=national). In the article, a methodology for establishing the supra-regional TSES is presented in more detail.  相似文献   

8.
Assessment of Global Seismic Loss Based on Macroeconomic Indicators   总被引:5,自引:0,他引:5  
Cha  L. S. 《Natural Hazards》1998,17(3):269-283
Most earthquake loss studies use a probabilistic approach in which predicted damages in various categories of structure and facilities in the region in concern are estimated and added together to obtain a total loss for particular intensity ranges. Such an approach requires a detailed inventory database of the structures and facilities in the region, which is not always readily available in many regions of the world. We have used an alternative means of estimating earthquake losses based on several macroeconomic indices such as the gross domestic product and population. Using published earthquake loss data for 1980–1995, the relations between GDP and earthquake loss have been formulated empirically for several intensity ranges. The world's land surface was divided into unit cells 0.5° lat. × 0.5° long. in size. The GDP of each cell was apportioned based on its population and GDP, and the population of the region to which it belongs. The predicted seismic loss of the cell was then estimated from the seismic hazard probability function, its GDP, and the empirical relation between GDP and seismic loss. A global seismic loss map is then compiled both for the intensity at 10% probability of exceedance and the probable maximum intensity. Employing readily available socioeconomic data as the basis for the vulnerability analysis, the method enables us to obtain seismic loss estimates for regions without the need for a detailed inventory of exposed structures or collateral geological information. Since such statistics are frequently compiled by the world's leading political and financial institutions, the seismic loss estimates can also be upgraded easily for the fast developing areas of the world.  相似文献   

9.
Atmospheric precipitation samples were collected in the Bohemian Karst (30 km SW from Prague, Czech Republic) at six localities in the vicinity of the limestone-quarry Čertovy schody during years 1996–2003. Samples were analyzed for major components (Na+, K+, Mg2+, Ca2+, F, Cl, NO3, HCO3, SO42−) and trace metals (Cu, Mn, Fe, Zn, Pb, Be, As, Sr, Cd, Al, Cr). Deposition fluxes were calculated from more than 10 000 elemental analyses of samples collected monthly. The fluxes of monitored substances show temporal and spatial variability. The most marked attribute is the strong affection by local emission sources confirmed by the investigation of seasonal variability, temporal trend and correlation analysis.  相似文献   

10.
In this paper aspects of the regional differentiation within the German Democratic Republic are presented, and the structure, dynamics and development of this differentiation are shown. The GDR founded after World War II comprises a territory of 108,000 sq.km with 16.7 million inhabitants. At the initial stage, its territorial structure was marked by a polarization between the industrialized regions in the South and the backward agricultural regions of the North and the East. Under socialist condition, however, his regional differentiation has been changed during the last three decades due to various basic and sequent processes. The foundation and development of a nationally-owned sector, particularly in industry, and a cooperative sector in agriculture, the industrialization of former agrarian regions, demographic processes, and a changing settlement structure has contributed to this development. The present regional differentiation is analysed by a new probabilistic approach, and seven macro-regions of the GDR are described.  相似文献   

11.
Bedford RD 《GeoJournal》1988,16(2):179-192
May 1987 is a month that will not be forgotten in the South Pacific. The first of two military coups d'etat led by Colonel Sitiveni Rabuka not only transformed the course of post-colonial political development in Fiji, but this event also had profound implications for international relations in the region. Co-incidentally, May 1987 was also the month when detailed results of Fiji's second national population census since Independence in 1970 became available. The 1986 census documents Fiji's population on the eve of a political revolution which has the potential to cause significant economic and social change. The demographic process most likely to be affected in the short-term by the coups is population movement, both within Fiji and to overseas destinations. This: paper examines developments in population movement between 1970 and 1986 with particular reference to an acceleration in levels of migration overseas by Indians and an exodus of Fijians from rural village communities for towns on Viti Levu and Vanua Levu. Trends in internal and international migration are evaluated at a range of spatial scales — national, regional and local. Some speculation on the effect of political and economic changes since May 1987 on these population movements attempts to provide a contemporary perspective on demographic developments over the last 15 years.  相似文献   

12.
额尔齐斯河流域中游地区是哈萨克斯坦共和国重要的水资源富矿与战略经济区, 资料表明这一地区过去几十年来气候与水资源均发生了显著变化, 分析研究其气候变化及其对水资源的影响, 对水资源合理利用具有重要的指导意义.利用研究区7个气象站1926-2009年84 a逐月降水和气温资料, 应用高桥浩一郎公式计算研究区月平均蒸发量及可利用降水量, 分析了1926-2009年研究区气候变化及其对水资源的影响.结果表明: 1)与全球气候变暖一致, 过去84 a来研究区平均气温呈较快的升高趋势, 且自20世纪80年代末以来进入快速升温变暖期; 2)84 a来, 研究区降水总体呈增加趋势, 随着温度的升高, 蒸发量同步增加. 因此, 研究区可利用降水量尽管有波动但总体变化不大; 3)降水是影响研究区可利用降水量的最重要的影响因素, 二者呈现显著的正相关关系, 1%的降水变化可导致1.68%的可利用降水量变化.研究区是全球气候变化的敏感区域, 水资源开发利用需切实做好应对气候变化的适应性对策.  相似文献   

13.
Long-term monitoring of water quality and phytoplankton was conducted at 19 sampling stations in Harima-Nada, eastern Seto Inland Sea, Japan for 35 years from 1973 to 2007. There were two significant long-term changes, an increase in winter water temperatures of 0.042°C year?1, and a decrease in dissolved inorganic nitrogen (DIN) from about 10 μM in the 1970s to ~5 μM in the late 1990s due to the reduction in nutrient inputs. DIN concentrations and total phytoplankton cell density were both higher during the 1970s to the early 1980s and then exhibited a significant decrease in the mid 1980s and remained relatively constant thereafter. Diatoms were the dominant phytoplankton group (>90%) over the 35-year period, and there was a dramatic shift from Skeletonema dominance (~70%) to Chaetoceros in the mid 1980s. This shift in diatom species may be attributed to differences in the life cycle of Skeletonema and Chaetoceros and the response to the decrease in DIN concentration.  相似文献   

14.
The biogeochemical study was carried out at the Lesni potok (LP)catchment, Central Bohemia, Czech Republic. The ecosystem was impacted by heavy acid depositionduring the industrial development in 1980–1990. The catchment is forested mostly by two tree species, Norwayspruce and European beech. The Be concentration in the granite bedrock is 12.6 mg kg-1. Theplagioclase contains the highest Be concentrations out of the rock-forming minerals. Elevatedconcentration of Be (5.4 mu;g L-1) in surface waters is a result of its mobilization from the soils(3.9 mg kg-1) and weathered rock by acid precipitation. As the pH of the precipitation and consecutivelypH of the surface waters is increasing in the Czech Republic, the Be concentrations in the surface watersgradually decrease. Groundwater with high pH values contains lower concentrations of Be (0.17 g L-1)than surface waters. The soils at prone area of the catchment are depleted in Be compared to thesoils in the riparian zones. The vegetation located on the prone area contains lower concentrations of theBe than vegetation at riparian zones. The monitoring of Be in the environment is important with respectto its possible harmful effects on aquatic biota and root systems of the plants.  相似文献   

15.
Ecosystem services are important to maintain the human well-being. However, their provisioning has been under the increasing pressure from both natural and socio-economic changes. This paper aims to assess the most significant hazards, such as water quality, nitrogen deposition, erosion, floods, invasive species, urbanisation and contaminated sites affecting delivery of ecosystem services in the Czech Republic. Using the multi-hazard assessment, the integrated risk index for ecosystem service provisioning was proposed. The spatial analysis based on this approach was then applied to the Czech Republic as a case study. The results showed that about 48% of the area falls into the very low risk category followed by 30%, 21%, and 1% for low, medium and high categories, respectively. Forest and wetland ecosystems were estimated to have the highest proportion of their total area among the highest risk values. Moreover, we found that the national parks appeared to have the highest proportion of medium- and high-risk classes among the natural areas. The approach presented in this study should aggregate the existing knowledge on ecosystem services and hazards and thus monitor the integrated risk. The results are intended to help with various planning and management decisions at both the national and regional levels and to bring more attention on the most problematic hot-spots.  相似文献   

16.
A change for the worse in water quality in Lake Biwa has led to musty odor of tap water, freshwater red tide and other water blooms by sudden propagations of nuisance planktonic algae since 1970. Further, some endemic and commercially important species of fish and molluscs decreased drastically in the last 10–30 years. These events seemed to be closely related to drainage of many small lakes channeled to Lake Biwa as part of an agricultural policy after World War 11, and to senseless exploitation of the littoral zone in the 1970s and 1980s as a link in the Comprehensive Development Project of Lake Biwa. Simplification of its littoral zone has led to a deterioration in its ecosystem through physical destruction of spawning habitats and increase in eutrophication.  相似文献   

17.
The Integrated Lake Watershed Acidification Study (ILWAS) model was used to simulate the recovery of the highly acidified Clearwater Lake, Ontario. Recovery started in the mid-1970s and continued through the 1980s in response to an estimated 30–50% decrease in S deposition from smelter emissions in nearby Sudbury, Ontario. Appreciable recovery of Clearwater Lake between the mid-1970s and 1987 is simulated by the ILWAS model, as indicated by a 50% decrease in SO4 concentration, an 80% decrease in total Al concentration, an increase in acid-neutralizing capacity (ANC) from −60 to −17 μeq/l, and an increase in pH from 4.2 to 4.8. These decreases in acidic constituents are in good agreement with monitoring data. Long-term simulations indicate that deacidification may continue until 2020, if S deposition rates remain at or less than the 1987 level. Simulations for years beyond 2020 yield yearly average ANC values of 18–40 μeq/l and pH values of 6.2–6.6, which are comparable to the estimated pre-smelter pH of 6.0–6.5 for Clearwater Lake. The agreement between simulated and monitoring data for the first 10 a of recovery and the simulated long-term recovery of the lake to its presmelter level of acidity lend confidence in the capability of numerical models to simulate the reversibility of watershed acidification and suggest that some highly acidic watersheds may eventually recover, given substantial decreases in acid deposition.  相似文献   

18.
In this work, we apply the Pattern Informatics technique for evaluating one surface expression of the underlying stress field, the seismicity, in order to study the Parkfield–Coalinga interaction over the years preceding the 1983 Coalinga earthquake. We find that significant anomalous seismicity changes occur during the mid-1970s in this region prior to the Coalinga earthquake that illustrate a reduction in the probability of an event at Parkfield, while the probability of an event at Coalinga is seen to increase. This suggests that the one event did not trigger or hinder the other, rather that the dynamics of the earthquake system are a function of stress field changes on a larger spatial and temporal scale.  相似文献   

19.
The concentrations of black carbon (BC) and δ13CBC were determined in sediments of three dated cores from the Pearl River estuary (core PR-3) and adjacent northern South China Sea (cores SS-30, E2). For comparison, the total organic C (TOC) contents and δ13CTOC in the sediments were also measured. Relatively higher concentrations and fluxes of BC were found in sedimentary core PR-3, taken in the Pearl River estuary. The BC concentration profiles or fluxes correlated well with fossil-fuel usage in the Pearl River Delta. Maximum BC fluxes occurred in the late 1970s to early 1980s as recorded in core PR-3, and in the 1950s (core SS-30), reflecting the maximum BC emission in the Pearl River Delta and Hong Kong region, respectively. After the 1980s, a rapid decrease of BC fluxes and a light δ13CBC excursion were presumably due to improvements in combustion and pollution-control technologies and a shift of energy structure from biomass and coal to a mixture of coal, gas, oil and biomass. The fossil BC that contributed to total BC in core PR-3 increased from 20–30% to 70–80% during the last five decades. The study also shows that BC correlates well with terrestrial organic matter and that the ratio of BC to TOC is a good pollution indicator in relation to anthropogenic activities.  相似文献   

20.
The frequency of natural disasters and the extent of their consequences at a global level are constantly increasing. This trend is partially caused by increased population vulnerability, which implies the degree of population vulnerability due to high-magnitude natural processes. This paper presents an analysis of vulnerability to natural disaster in Serbia in the second half of the twentieth and the early twenty-first century. Vulnerability changes were traced on the basis of demographic–economic indicators derived from statistical data for local government units (municipalities) provided by the Statistical Office of the Republic of Serbia. Calculations were performed in the geographical information system environment. The results of the study show that spatial and temporal vulnerability variations are causally correlated with changes in the selected components. Significant rise of vulnerability is related to urban areas, while lower values are characteristic for other areas of Serbia; this is primarily a consequence of different population density.  相似文献   

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