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1.
In this century, sport has steadily become a more visible and marketable part of everyday life and of global political significance. States have consequently used sport as a means of soft power in order to develop a positive international presence and, usually to a lesser extent, affirm national identity. Sport diplomacy is usually associated with mega‐events and large states, but Fiji has used its prowess in rugby, and its Sevens victory in the 2016 Olympic Games, to promote itself globally, strengthen its national image and support government claims to legitimacy. The government emphasised Fijian values to construct a banal nationalism, in the face of ethnic divisions, and external concerns over repression of civil society. At least ephemerally, Fiji acquired new international recognition, and the government gained national legitimacy, indicating the expanding role of sport in geopolitics.  相似文献   

2.
《自然地理学》2013,34(5):418-426
The Navua River on the main island of Fiji displays anomalous drainage features and associated fluvial forms. The River course makes a right-angled bend approximately halfway along its course, beyond which it flows through a narrow gorge cut into hard volcanic rocks. Several tributaries enter the gorge as high cascades from hanging valleys. It is proposed that the former course of the palaeo-Navua River flowed east in a straight line along the modern Waidina River, and eventually discharged into Fiji's Rewa River system. Evidence for this is the presence of a spectacular dry gorge (a wind gap) at the head of the Waidina River. Previous ideas of river capture fail to explain the evolution of the local fluvial geomorphology. Instead, tectonic uplift probably dammed the palaeo-Navua and diverted it to its present short course to the sea. This new hypothesis provides a more plausible, simultaneous account for all the major fluvial geomorphic features, their geographical distribution and their relationship with geology in the Navua region.  相似文献   

3.
Fluvial processes, especially rates of floodplain accretion, are less well understood in the wet tropics than in other environments. In this study, the caesium-137 (137Cs) method was used to examine the recent historical sedimentation rate on the floodplain of the Wainimala River, in the basin of the Rewa River, the largest fluvial system in Fiji and the tropical South Pacific Islands. 137Cs activity in the floodplain stratigraphy showed a well-defined profile, with a clear peak at 115 cm depth. Our measured accretion rate of 3.2 cm year−1 over the last ca. 45 years exceeds rates recorded in humid regions elsewhere. This is explained by the high frequency of tropical cyclones near Fiji (40 since 1970) which can produce extreme rainfalls and large magnitude floods. Since the beginning of hydrological records, large overbank floods have occurred every 2 years on average at the study site. The biggest floods attained peak flows over 7000 m3 s−1, or six times the bankfull discharge. Concentrations of suspended sediments are very high (max. 200–500 g l−1), delivered mainly by channel bank erosion. In the future, climatic change in the tropical South Pacific region may be associated with greater tropical cyclone intensities, which will probably increase the size of floods in the Rewa Basin and rates of floodplain sedimentation.  相似文献   

4.
Low‐energy gamma ray spectroscopy has been employed to estimate floodplain sedimentation rates using measurements of 210Pb in floodplain alluvium. The utility of the technique is assessed through the analysis of excess (unsupported) 210Pb profiles in three sediment cores taken from the floodplain of the Labasa River on Vanua Levu in northern Fiji. A low‐energy germanium spectrometer (LEGe) was used for the nondestructive determination of excess 210Pb in a region cultivated intensively with sugarcane. Measured average historical (c. 25 years) vertical accretion rates are between 2.2 and 4.4 cm yr?1. The findings are broadly comparable with published sedimentation rates from analyses of radionuclide profiles elsewhere in the tropical South Pacific Islands, but the rates are higher than those measured previously at the same Labasa River sites using 137Cs profiles. Accelerated soil erosion owing to cane burning and land tillage seems to be largely responsible for sediment production, although flood‐related effects such as channel accretion by coarse bedload and the emplacement of large organic debris also influence floodplain sedimentation. However, application of the 210Pb technique in Fiji (and perhaps neighbouring island countries) is found to have serious drawbacks compared to the more robust 137Cs method, owing principally to the low 210Pb concentrations in the sandy alluvial sediment tested.  相似文献   

5.
Development assistance agencies have long urged developing countries to adopt environmental management techniques used in industrialized countries. They have ascribed shortcomings in the way developing states use those techniques to insufficient training, environmental matters being poorly integrated into economic decision making, other institutional weaknesses and lack of capacity. These reductionist explanations ignore the influence that socio-political and economic factors may have on state environmental management. They afford only a limited understanding of environmental practice in the Fiji Islands, a South Pacific archipelago and republic. The attempts of Fijian chiefly élite to maintain their power base – achieved through political participation in the state and economic development activities as much as through maintaining the communal system – shape the state's environmental management practices. Those practices have far less rational and democratic bases than one would expect either from the underlying logic of the techniques used (such as environmental impact assessment, environmental planning and protected areas), or from the way those techniques are applied in western, industrialized countries.  相似文献   

6.
This paper reviews changes in the development and peripheralized status of the Fijian island of Kadavu from a 20‐year perspective. A combination of microgeographic studies in three villages and a mesogeographical analysis show that the conditions of internal dependency found in Kadavu in the early 1980s had not changed much: the pattern of cash crop production and trade remained almost entirely dependent on the yaqona (Pacific kava) beverage crop; shipping services provided by core agents had not improved; the island had experienced significant outmigration; and government initiatives to change the trend were limited. These elements perpetuate a core–periphery structure in Fiji that hampers the development of a self‐sufficient periphery. For Kadavu villagers, however, the benefits derived from the continued form of non‐capitalist production afford them a certain degree of autonomy vis‐à‐vis the market economy, which might be to their advantage under the ongoing conditions of peripheralization.  相似文献   

7.
明清时期太湖流域的中心地结构   总被引:4,自引:0,他引:4  
陆玉麒  董平 《地理学报》2005,60(4):587-596
太湖流域是长江三角洲的核心组成部分。研究表明,该地区虽然水网密布,水系发达,并有太湖等大小湖泊存在,但并不影响中心地结构在该区域的形成,其形成机理是地形平坦、水系呈规则的圩田塘埔系统,及高度发达的市场体系。该中心地结构的中心城市是苏州,而苏州位于太湖流域的几何中心;另一方面,不同等级中心地的间距之间存在着高度的对应性。据此,根据太湖流域中心地的形成过程,可以给出以下的中心地结构的形成路径:区域几何中心决定最高等级中心地的区位;区域面积决定一级中心地与二级中心地之间及二级中心地之间的距离;高等级中心地之间的间距决定以后,余下的不同等级中心地之间的距离即可同时决定。由此,太湖流域中心地结构的形成体现了典型的自上而下的中心地形成过程与类型。这一形成过程具有一般性,即对任何一个中心地而言,都有一个自低等级中心地向高等级中心地的转化、升级过程,但对整个区域而言,却是高等级中心地首先形成,然后才是以此为中心各级不同等级中心地的相继形成,最终形成完整的中心地等级体系。其研究结论丰富与完善了中心地学说。  相似文献   

8.
For the first time, a sediment core spanning the entire Holocene has been analysed from Fiji. The 6 m core was obtained from the floor of an ancient coastal lagoon (palaeolagoon) adjacent to Bourewa, the site of the earliest known human settlement in this island group. The basal sediments, just above bedrock, date from 11 470 cal bp. A major transition occurs around 8000 cal bp where marine influences on palaeolagoon sedimentation increase sharply. Full shallow-water marine conditions are attained around 4630 cal bp and last until 3480 cal bp after which there is a regressive phase. The results agree with the area-specific predictions of sea level in the ICE-4G model, particularly in the timing of the highstand. In addition, the results support the ideas (a) that early human colonisation of Fiji occurred during the late Holocene regression, (b) that the first inhabitants of Bourewa utilised both nearshore marine (reefal) and brackish lagoon food sources, and (c) that the abrupt human abandonment of the area around 2500 cal bp could have been prompted by a reduction in these resources driven largely by sea-level fall.  相似文献   

9.
We utilized carbonate clumped isotope thermometry to explore the thermal history of the Delaware Basin, West Texas, USA. Carbonate wellbore cuttings from five oil/gas wells across the basin yielded clumped isotope temperatures (T(Δ47)) ranging from 27°C to 307°C, interpreted to reflect a combination of initial precipitation/recrystallization temperature and solid-state C-O bond reordering during burial. Dolomite samples generally record lower apparent T(Δ47)s than calcite, reflecting greater resistance to reordering in dolomite. In all five wells, clumped isotope temperatures exceed modern downhole temperature measurements, indicating higher heat flow in the past. Using modelled burial curves based on sedimentological history, we created unique time-temperature histories by linearly applying a geothermal gradient. Applying two different thermal history reordering models, we modelled the extent of solid-state C–O bond reordering to iteratively find the time-averaged best-fit geothermal gradients for each of the five wells. Results of this modelling suggest that the shallower, southwestern portion of the study area experienced higher geothermal gradients throughout the sediment history (~45°C/km) than did the deeper, southeastern portion (~32°C/km), with the northern portion experiencing intermediate geothermal gradients (~35–38°C/km). This trend is in agreement with the observed gas/oil ratios of the Delaware Basin, increasing from east to west. Furthermore, our clumped isotope temperatures agree well with previously published vitrinite reflectance data, confirming previous observations and demonstrating the utility of carbonate clumped isotope thermometry to reconstruct basin thermal histories.  相似文献   

10.
The islands Ovalau and Moturiki in central Fiji are selected for the investigation of coastal change over the past c. 200 years. Although having coastal environments typical of many tropical Pacific Islands, Ovalau and Moturiki are also atypical because they experienced urban and infrastructural developments before most other parts. The associated records enable recent coastal changes to be discerned more clearly here than has been possible elsewhere. The islands are surrounded by coral reef, the configuration of which accounts for variations in vulnerability of their coasts to erosion. Interviews were conducted in each of 22 settlements along the islands' coasts and information obtained about recent coastal change. Mangroves are concentrated along leeward coasts, although they have been cleared from many windward coasts in the last 40 + years, causing shoreline erosion to be initiated/accelerated. Most shoreline-protection initiatives (vegetation planting and seawall construction) have failed. Three major management implications of the study are discussed. Firstly, there is a need to redefine the nature of the interactions between coastal inhabitants and coastal ecosystems, so that environments are sustainably developed; and specifically that reefs are conserved and shoreline vegetation (especially mangroves) is effectively replanted. Secondly, information about appropriate design and composition of artificial structures for shoreline protection needs to be made available to the local communities who construct most of them. Thirdly, alternative sources of sand and rock aggregate to those whose extraction aggravates shoreline erosion should be sought.  相似文献   

11.
Thet1'onessofpopulationasbotl1producerandconsumerdetennjneshlatpopulahontakesaveryDimportanposih0nintheregionalsoci0ec0n0ndcdevelopmenLThecontradichonbetWeenp0pulationandwater,land,envirnmentandeconondcdevel0pmentistheInainoneintheregi0ItalPREDSystem.ThoughtheQaihoBasinhasvastexpanseoftenainandabundantresources,thet0ughnaedcondihonsofdryandcoldcllInaelllmakesitveryhardforhumanliving.Meanwhile,theecon0ndcdevelopmentmodedsgres0urcesexPloitahonaspriorityrequiresasultablegr0wthrateofp0pulaho…  相似文献   

12.
Source rock evaluation is a critical factor in resource assessment of oil and gas. Models for evaluating source rocks are dependent on established geomathematical principles, the calculation of source-rock parameters, and geological data. The sensitivities and uncertainties associated with these models are a matter of concern. In this paper, the effects and relative contributions of 13 major geological factors, as well as their variations and distribution probabilities, have been analyzed for the source rocks in the North Songliao Basin in northeastern China. The geological factors include the time of formation of the regional caprock, composition of the regional caprock, the phases of hydrocarbons in migration, and those factors associated with the generation, retention, and expulsion of hydrocarbons and their effects on source-rock efficiency. Of the 13 factors analyzed, the most important are the source-rock depth, sedimentation rate, total organic content, and kerogen-type index; the relative contributions to the uncertainty of efficient gas/oil migration amounts for the most important factors are 37, 25, 19, and 1% for oil and 32, 17, 20, and 15% for gas, respectively. These most reflect the changes that have occurred in the Qingshankou source rocks.  相似文献   

13.
Discovery process modeling has gained wide acceptance in the Chinese exploration community. In recent years, a variety of discovery process models have been applied to the prediction of undiscovered petroleum resources at the play level in sedimentary basins in China. However, challenging problems have been encountered, particularly when one method alone has been applied to small plays in nonmarine sedimentary basins or in plays with an unusual order of discovery wells. This paper presents results gotten by using the lognormal discovery process model of the Geological Survey of Canada and the geoanchored method for three petroleum plays in basins with different geologic settings. Although the predicted shapes of the parentsize distributions which use these two models, were not always similar, the expected values of the total resources and the number of fields (pools) to be discovered are comparable. The combined use of two discovery process models in the same play compensates for the weaknesses in one method compared with the other and vice versa. Thus, more reliable estimates are the result.  相似文献   

14.
作为一种风蚀地貌,雅丹地貌是对环境长期适应的一种表现,其形态特征可以反映所受内外营力的作用。对火星埃律西昂平原和地球柴达木盆地雅丹体的形态参数进行对比分析。结果显示:(1)埃律西昂平原雅丹体的长宽比(3.49)与柴达木盆地雅丹体的长宽比(3.57)较为接近,同时也与理想状态下的长宽比(4)接近,它们都具有流线型的形态,且处于雅丹体发育的成熟期。(2)柴达木盆地雅丹体是鲸背状,埃律西昂平原雅丹体是椭圆状,原因是柴达木盆地雅丹体常年受盛行风的影响,埃律西昂平原雅丹体受两种反向风的影响。柴达木盆地雅丹体表面崩裂的痕迹不明显,埃律西昂平原雅丹体表面崩裂的痕迹比较明显,原因是形成雅丹体的物质基础和温差环境不同:柴达木盆地雅丹体的物质基础是湖相沉积物,雅丹体表面有减弱风化的盐壳;埃律西昂平原雅丹体的物质基础是火山熔岩流,而且火星的昼夜温差大于地球。  相似文献   

15.
Solar radiation is an important driving force for the formation and evolution of climate system. Analysis of change in solar radiation is helpful in understanding mechanism of climate change. In this study, the temporal and spatial variations of solar radiation and the cause of the change in solar radiation have been analyzed based on meteorological data from 46 national meteorological stations and aerosol index data from TOMS over the Haihe River Basin and surrounding areas. The results have shown that solar radiation and direct radiation significantly decreased, while scattered radiation increased during the period 1957–2008. Spatially, the decreasing trend of solar radiation was more and more significant from low population density areas to high population density areas. The spatial distribution of increase in aerosol index is consistent with that of decrease in solar radiation. The increase in aerosols resulting from human activities was an important reason for the decrease in solar radiation.  相似文献   

16.
海河流域及周边地区太阳辐射变化成因   总被引:1,自引:1,他引:0  
Solar radiation is an important driving force for the formation and evolution of climate system. Analysis of change in solar radiation is helpful in understanding mechanism of climate change. In this study, the temporal and spatial variations of solar radiation and the cause of the change in solar radiation have been analyzed based on meteorological data from 46 national meteorological stations and aerosol index data from TOMS over the Haihe River Basin and surrounding areas. The results have shown that solar radiation and direct radiation significantly decreased, while scattered radiation increased during the period 1957–2008. Spatially, the decreasing trend of solar radiation was more and more significant from low population density areas to high population density areas. The spatial distribution of increase in aerosol index is consistent with that of decrease in solar radiation. The increase in aerosols resulting from human activities was an important reason for the decrease in solar radiation.  相似文献   

17.
长江、黄河流域生态系统服务变化及权衡协同关系研究   总被引:6,自引:1,他引:5  
长江、黄河流域是中国重要的生态屏障,近几十年来强烈的人类活动改变了长江、黄河流域的自然景观,使生态系统功能遭到破坏,了解流域内生态系统服务的变化、相互作用和驱动因素是流域生态系统管理和调控的重要基础。本文利用土地利用、土壤类型和气象等数据,对2000—2016年长江、黄河流域的NPP、土壤保持和产水服务进行时空变化分析;采用相关分析法和约束线研究生态系统服务之间的权衡协同关系和约束效应。结果表明:① 2000—2016年,长江、黄河流域的NPP分别以3.21 gC/m2和3.92 gC/m2的速率递增,产水量和土壤保持量在长江流域分别以1.25 mm/a的速率递增和55 t/hm2的速率递减,而在黄河流域,产水量和土壤保持量分别以0.04 mm/a的速率递减和3.31 t/hm2的速率递增。② 长江、黄河流域的NPP、土壤保持和产水服务之间互为协同关系。长江流域的NPP和产水服务与土壤保持服务之间为驼峰型约束,NPP与产水量之间为凸波型约束。③ 黄河流域的NPP与土壤保持间的约束线形态为凸波型,NPP与产水量之间为驼峰型约束,而产水量与土壤保持之间为指数型。定量化研究不同流域的生态系统服务并探究其影响因素,对于了解和优化不同地区的生态系统服务有重要意义。  相似文献   

18.
中国珠三角盆地和日本关东盆地平地人口密度对比研究   总被引:1,自引:0,他引:1  
改革开放以来,大量人口向珠三角盆地聚集,不断增加的人口负荷给区域可持续发展带来巨大压力,也给珠三角盆地国土承载力带来挑战。以中国珠三角盆地和日本关东盆地作为研究区,选取2地2000和2010年普查人口和国土面积数据,进行计算、分析和对比,认为用可居住的平地人口密度才能真实反映区域人口压力状况。研究结果表明,日本关东盆地人口增长率从1995年开始已降到0.5%,人口承载力接近饱和。以人口承载力接近饱和的日本关东盆地为参考对象,对比中国珠三角盆地和日本关东盆地的平地人口密度,2000年时中国珠三角盆地的平地人口密度低于日本关东盆地,珠三角盆地还有一定吸纳人口的能力;2010年时中国珠三角盆地的平地人口密度已超过日本关东盆地,其人口规模已经接近其国土承载力极限,进一步集聚人口的能力已经非常有限。依靠人口集聚发展劳动密集型产业推动经济增长的传统发展模式已经难以为继,转变经济发展方式势在必行。  相似文献   

19.
近40年来塔里木河流域气候及径流变化特征研究   总被引:4,自引:0,他引:4  
以塔里木河流域的21个气象站和10个水文站1961~2000年观测资料为基础,对塔里木河流域的温度、降水及径流变化进行了分析.结果得出:(1)20世纪60年代以来塔里木河流域的年平均气温呈逐年代递增趋势,源流区的年平均气温增高了0.57℃,上游区增高了0.6℃,中游区增高了0.7℃,下游区增高了0.8℃,越往下游方向变暖趋势越明显,并且气温增高幅度逐步加大.(2)60年代以来塔里木河流域的年降水量也逐年递增,但是与温度的增幅趋势相反,从源流区到下游区,降水增幅逐步减少,源流区平均增加了34.2%,上游区增加了22.0%,中游区增加了15.3%,下游区只增加了6.1%.(3)该流域各源流的出山口径流量除和田河减少外,阿克苏河增加9.04亿m3,叶尔羌河增加5.51亿m3,开都河增加9.27亿m3.(4)该流域源流径流受温度和降水变化的双重影响,源流区的气候变暖和变湿是塔里木河源流径流量增长的一个非常重要的因素.  相似文献   

20.
选取汾河中下游临汾盆地作为研究区,基于多年地下水埋深监测数据,对该地区地下水埋深时空变化规律及其控制因素进行系统分析,研究表明:① 研究区2007—2018年地下水埋深整体呈现增加趋势;各区域地下水埋深差别显著,空间上呈现东高西低的趋势,其中尧都、襄汾出现明显的超采现象。② 地下水埋深在2010年后波动较显著,各区县变幅明显高于2010年前的时段。③ 地下水埋深在年尺度上表现出从北向南逐渐增加的趋势,春季地下水埋深变化幅度最大且主要以地下水埋深降低为主;空间上,地下水埋深变浅区域主要集中在霍州、洪洞、曲沃南部和翼城北部,加深区域主要集中在襄汾、尧都西南部和侯马西北部少部分区域。④ 研究区地下水埋深变化对蒸发量较敏感,对降雨量和农村用水敏感较弱,人口对地下水埋深变化贡献率较大。  相似文献   

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