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1.
News media influence local to global interactions between people, societies, and governments by producing place images. Representations of Africa in Western news media are heavily imbued with colonialist notions of cultural geography. In particular, Western news media have represented conflicts in Africa as ‘tribal’, a trope that erases geographic and historical context, and discourages actions that could prevent or reduce violent conflict. To determine if ‘tribalism’ remains important in coverage of African conflict, we use framing analysis to evaluate news on Sudan’s Darfur region in The New York Times and The Washington Post during 2003–2009. We find that these newspapers predictably relied on stereotypes related to tribalism to simplify Darfur’s geography and make the conflict meaningful to intended readers. Tribal portrayal of African war is inherently political, and, problematically, neither newspaper recognized that their use of the tribal narrative was parallel to the views of both the Sudanese government and external observers that challenged the actions of the Sudanese government. However, we also found that stereotypical representations became less prominent over time, apparently because reporters found that the initial, simplistic framing of the conflict did not match their encounters with geographic reality. We emphasize the decline in stereotypical tropes, because this suggests behind-the-scenes negotiation about representations in these news organizations. Recognizing voices that challenge stereotypical portrayals is necessary to developing place images that are geographically more accurate.  相似文献   

2.
We discuss historical evidence for seismicity on the southern margin of the Siberian craton collected from old local newspapers. The reported earthquakes vary in magnitude from M = 2.5 to 4.5, and their macroseismic locations agree well with the regional tectonic framework. The new data prove seismic activity in the area and can be used in seismic risk assessment.  相似文献   

3.
China, whose distribution area of karst region reaches about 3.63 million km2, is one of the countries that have the widest karst collapse development. In modern-karst collapses, the karst collapse induced by water environment is an important type in karst collapses of North China. This paper completed a systematic study on the relations between groundwater environmental transformation and karst collapses and their distribution rules in northern China and found out that the karst collapses in northern China are closely related to the change of groundwater environment, which increased along with the declining groundwater levels and increasing hydraulic gradient. Meanwhile, it was also found that in all cases of collapse caused by underground-environmental change of northern China, pumping collapses in urban areas appeared to be the commonest and strongest among modern-karst collapses with 20 regions and 796 mining pits in total, which account for 30.7 and 58% of artificial collapses, respectively, followed by collapses that were induced by mining draining and inrushing water with 33 regions and 282 mining pits, accounting for 20.4%. In addition to the conditions listed above, there were also a few water caving collapse and leakage collapse.  相似文献   

4.
Kreuzer  Thomas M.  Damm  Bodo  Terhorst  Birgit 《Landslides》2022,19(2):505-513

Landslide research chiefly relies on digital inventories for a multitude of spatial, temporal, and/or process analyses. In respect thereof, many landslide inventories are populated with information from textual documents (e.g., news articles, technical reports) due to effectiveness. However, information detail can vary greatly in these documents and the question arises whether such textual information is suitable for landslide inventories. The present work proposes to define the usefulness of textual source types as a probability to find landslide information, weighted with adaptable parameter requirements. To illustrate the method with practical results, a German landslide dataset has been examined. It was found that three combined source types (administrative documents, expert opinions, and news articles) give an 89 % chance to detect useful information on three defined parameters (location, date, and process type). In conclusion, the definition of usefulness as a probability makes it an intuitive, quantitative measure that is suitable for a wide range of applicants. Furthermore, a priori knowledge of usefulness allows for focusing on a few source types with the most promising outcome and thus increases the effectiveness of textual data acquisition and digitalisation for landslide inventories.

  相似文献   

5.
A new theropod dinosaur, Shidaisaurus jinae gen. et sp. nov., has been described on the basis of an incomplete skeleton. The specimen was found near the base of the Upper Lufeng Formation (early Middle Jurassic) in Yunnan, China. It is the first theropod dinosaur from the Middle Jurassic of Yunnan. Shidaisaurus jinae is distinguishable from other Jurassic theropods by certain features from the braincase, axis, and pelvic girdle. The absence of any pleurocoels in the axis or in any anterior dorsal vertebrae suggests that the new Lufeng theropod is relatively primitive and more plesiomorphic than most of the Middle to Late Jurassic theropods from China. Most Chinese taxa of Jurassic theropod dinosaurs have not been well described; a further detailed study will be necessary for us to determine their phylogenetic relationships with Shidaisaurus jinae.  相似文献   

6.
ABSTRACT

In the bridge design specifications of the American Association of State Highway and Transportation Officials (AASHTO) using the Load and Resistance Factor Design (LRFD) method, the loads and resulting force effects are given two-letter designations, e.g. “SE” for “force effects due to settlement”. The SE load factor is used to develop factored values of the induced force effects such as moments and shears in a bridge structure due to foundation movements. In 2018 AASHTO committees voted to adopt calibrated values of the SE load factors that account for the uncertainty in predicted foundation movements from different analytical methods. However, additional uncertainty can occur in the differential settlements. This paper explores the additional uncertainty in differential settlements of bridge foundations and retaining walls using the datasets for two analytical methods that were used by AASHTO to develop the SE load factors for foundation settlement. Normalised probability exceedance charts (NPECs), that integrate the concept of reliability index and data correlation, have been developed and their application in bridge and wall design process is discussed for a variety of scenarios. Guidance is provided for the practical implementation of differential settlement in bridge analysis through an example problem.  相似文献   

7.
An unusual liptinite coal component has been reported in the Chinese literature over the past sixty years. It has been described as a maceral in the Chinese National Standard (1991), but it has not been named internationally. In Chinese literature it is called “barkinite”, on the basis of its morphological features and because it is believed to have originated as bark tissue.“Barkinite” occurs in Late Permian, marine-influenced coals and is best represented in the Changguang, Leping and Shuicheng Basins of southern China.The material originates from plant periderm or the bark of higher plants. However, “bark” contains a variety of substances, including resin and suberin, which are recognised as the precursors of the resinite and suberinite macerals. “Barkinite” is distinguished by (i) its thickness; individual pieces can be more than ten cells thick and several centimetres long and (ii) it fluoresces strongly at 0.6% vitrinite reflectance and loses its fluorescence at about 1.1% vitrinite reflectance.The reporting of “barkinite” from only Chinese coals may be due to its origin from Lepidodendron and Psaronius flora, which was common in the Northern Hemisphere during the Carboniferous, but which was isolated to China by the Late Permian. It is proposed that the remnant flora evolved into unique forms in China by the Late Permian. Lepidodendron and Psaronius remains, coupled with a strongly marine-influenced, peat-forming environment have given rise to “barkinite” and to its restricted distribution.  相似文献   

8.
China has suffered from severe earthquake disasters in recent years. In order to explore the impact of severe earthquakes on public risk perception on different time scales, four surveys were conducted twice each after the severe Wenchuan and Yushu earthquakes. t tests were performed between two consecutive surveys to explore the change of public risk attitudes. The results demonstrated that after the two severe earthquakes, the public seismic risk acceptance has increased over time, and the comparison between pre- and post-Yushu earthquake illustrated that the severe disaster had more impact on vulnerable population such as females, children and low-income people. Moreover, linear regression models were employed to find the determining factors of public acceptance towards earthquake risks. It was discovered that the public perceived earthquake effect had significant negative relationship with seismic risk acceptance, and public trust towards local government had positive relationship with the risk acceptance. This study could help government to gain better understanding of public mental status and take more effective disaster preparedness measures when preventing and responding to a severe earthquake.  相似文献   

9.
张傲  邵长生  王岑  杨艳林  路韬 《中国地质》2019,46(S2):50-59
依托自然资源部中国地质调查局部署的"长江中游城市群咸宁-岳阳和南昌-怀化段高铁沿线1:50 000环境地质调查"项目,开展了蒲圻县幅1:50 000环境地质调查。本数据集采取水文地质调查、岩溶地面塌陷调查、水文地质钻探、水质测试分析等方法而形成。数据集包含73个泉水调查点、7个矿泉水测试分析结果、1个岩溶地面塌陷点、7个岩溶洞穴点、10个水文钻孔等5方面数据。其中泉水调查成果包括泉点的分布位置、野外水质检测指标、泉水成因等;矿泉水分析结果为针对区内泉点及水文钻孔所取水样进行室内测试,达到矿泉水标准的测试结果;岩溶地面塌陷数据主要包括岩溶地面塌陷的位置、塌陷坑特征、地质背景、塌陷后状态等信息;岩溶洞穴调查成果包括洞穴点的位置、洞穴发育特征、开发利用情况等信息;钻孔基本情况数据为钻孔位置信息、孔径、孔深等信息。数据集为赤壁市城镇规划建设,土地安全利用,优质地质资源开发提供重要的地质数据源支撑。  相似文献   

10.
Based on the results of a study of regional element abundance in eastern China and the 1:200 000 geochemical surveys in northern Xinjiang, the element geochemical characteristics of the exposed crust in 23 tectonic units of the continent of China are summarized. Compared with the global average abundance of the upper continental crust, the exposed crust of the continent of China is compositionally more evolved than the upper crust of the island arc, but less evolved than the mature Precambrian Canadian shield. The exposed crust of the North China and Yangtze platforms has a lower SiO2 content, but markedly higher CaO and MgO contents due to the presence of widespread carbonate strata, which suggests that we should not neglect the contribution of carbonate rocks in the study of the exposed crust and the element abundance of the upper crust. In comparison with two recently published average compositional models of the global upper continental crust, the exposed crust of the continent of China is depleted in Au, Hg, Mo, Sn, and W, which suggests that their abundance in the present global models is overestimated. The exposed crust of the North China platform and the Qinling-Dabieshan fold belt to its south has lower μ(238U/204Pb) values (<8), but other regions of the continent of China exhibit much higher μ values, which implies that the low μ feature of the North China platform and its adjacent regions does not have global significance. Considering the apparent lateral variation in composition of the exposed crust for the tectonic units of the continent of China, there is no adequate reason to take the average upper crust compositional model of the North China platform and its adjacent regions as a reliable composition representative for Chinese and global upper continental crust composition. Translated from Geological Bulletin of China, 2005, 24(10–11): 906–915 [译自: 地质通报]  相似文献   

11.
From winter 2009 to spring 2010, southern China suffered from an extensive and lengthy drought. Subsequently, southern China experienced torrential rains a dozen times during the flood season of April–June. The prolonged drought and subsequent intensive rainfall dramatically altered the hydrodynamic conditions of the karst areas, causing hundreds of widely distributed karst collapses, with extensive damage to houses and fields and necessitating the evacuation of many people. Understanding the causes of these collapses will provide a scientific basis for the prediction or prevention of the related risk. Thus, a geologic survey of karst collapses was performed that systematically allowed to analyze the basic geological conditions, groundwater hydrodynamic conditions, overlying strata properties, and environmental and climatic conditions in southern China. The results showed that environmental and climatic changes, especially the drastic changes in rainfall, gave rise to striking changes in karst hydrodynamic conditions that accelerated infiltration, suffosion, dissolution, and transportation rates and also changed the physical and mechanical properties of the strata overlying karst caves. These stressors triggered or facilitated both cave formation and collapse.  相似文献   

12.
Summary The metabasites in Tunchang area, East-central Hainan Island, South China generally display strongly LREE-depleted patterns, extremely low HFSE concentrations and relatively high LILE contents; a few boninite-like samples have a concave-up, slightly LREE-enriched pattern. The low but variable Ti/V ratios between 6 and 20, and the high mg-numbers and Cr, Co, Ni contents, are indicative of plume-influenced intraoceanic arc magmas. It accord with this model are moderately high ɛNd(t) values ranging from +2.16 to +6.75, and 87Sr/86Sri values ranging from 0.70239 to 0.70824. These geochemical features imply that the protoliths for the Tunchang area metabasites are relics of an intra-oceanic island arc and the parental melts of these rocks were generated from a depleted, primitive mantle arc source rather than from a N-MORB source in a supra-subduction zone-like setting. The minor geochemical differences between the two identified groups of metabasites are due to a combined result of the variable degree of partial melting and the crystal fractionation of clinoproxene ± olivine ± plagioclase. The Tunchang area metabasites are distinctive in geochemical and isotopic compositions, and likely also in age from the Bangxi area metabasites in the northwestern part of Hainan Island. We assume that the NE–SW trending Baisha Fault Zone likely marks an early suture zone due to the collision of an Early Paleozoic intra-oceanic arc with the South China continent. In contrast, the Bangxi area metabasites more likely are formed in an extensional back-arc basin due to subduction of the Paleo-Tethys beneath the South China continental margin during the Late Paleozoic. Present address: Chinese Academy of Sciences, Guangzhou Institute of Geochemistry, Guangzhou, Guangdong Province 510640, People’s Republic of China Authors’ addresses: Deru Xu, Bin xia, Pengchun Li, Guanghao Chen, Tao Chen, Key Lab of Marginal Sea Geology, Chinese Academy of Sciences, Guangzhou Institute of Geochemistry, Guangzhou, Guangdong Province 510640, People’s Republic of China; Bakun-Czubarow Nonna, Bachlinski Robert, Polish Academy of Sciences, Institute of Geological Sciences, Institute of Geological Sciences, ul. Twarda 51/55, 00-818 Warszawa, Poland  相似文献   

13.
A dramatic increase in prevalence of the recently discovered bopyrid isopod parasite, Orthione griffenis, likely introduced in the 1980s from Asia to the Pacific coast of North America, coincided with the 2002 collapse of a population of its burrowing mud shrimp host, Upogebia pugettensis, in Willapa Bay, Washington that had been stable since monitoring began in 1988. An examination of whether O. griffenis infections were sufficient to cause this decline and other recently noted U. pugettensis population collapses in Pacific Coast estuaries was conducted. O. griffenis prevalence was the highest in large reproductive-sized female shrimp and caused an estimated average 68% loss of U. pugettensis reproduction in Yaquina Bay, Oregon over a 5-year period. O. griffenis prevalence fluctuated from year to year, but trends were similar in all estuaries sampled. Uninfected shrimp transplanted back into locations from which they had disappeared acquired the parasite, suggesting that O. griffenis is extremely effective at finding its host even in estuaries with very low host density. Since both U. pugettensis and O. griffenis have pelagic larval stages, their population dynamics are also influenced by coastal nearshore oceanography and estuarine recruitment success. Coastwide lack of estuarine recruitment appears to coincide with declines in density of a co-occurring thalassinid shrimp, Neotrypaea californiensis, but cannot alone explain U. pugettensis population collapses. Although patterns observed to date could be explained by the presence of either a native or introduced parasitic castrator, assumptions of a resilient co-evolved host–parasite relationship do not apply for introduced species, so continued efforts to follow the spatial extent and consequences of the O. griffenis–U. pugettensis host–parasite relationship are warranted.  相似文献   

14.
In this paper, we present an approach to modelling multicriteria flood vulnerability which integrates the economic, social and ecological dimension of risk and coping capacity. We start with an existing multicriteria risk mapping approach. The term risk is used here in a way that could be called a starting point view, looking at vulnerability without considering coping capacities. We extend this approach by a multicriteria modelling of coping capacities towards an end point view of vulnerability. In doing so, we explore a way to differentiate coping capacity from flood risk in each of the dimensions of vulnerability. The approach is tested in an urban case study, the city of Leipzig, Germany. Our results show that it is possible to map multicriteria risks as well as coping capacities and relate them in a simple way. However, a detailed calculation of end point vulnerability would require more detailed knowledge on the causal relationships between risk and coping capacity criteria and their relative importance.  相似文献   

15.
In a paper written immediately after the reopening of the Suez Canal in 1975, a question was raised: is the Israeli Negev a viable alternative to the Suez Canal? (Geoforum, 8, 29–32, 1977). The answer posted then was pessimistic — the continental land bridge was seen as having failed to function as a real alternative.Now, two years after the reopening of the Canal, it appears that the land bridge seems to be a more economically viable venture than previously suggested. The amount of cargo in transit over the land bridge and its percentage of the total port of Eilat traffic is increasing despite competition from the Canal. This phenomenon and new perspectives on the Negev land bridge are discussed in this follow-up paper.  相似文献   

16.
黄河清 《山东地质》2012,(3):65-67,70
国土资源管理中遭遇的资源供需矛盾、利益协调困难、违法违规反弹、粗放浪费严重等问题,只是保障发展、保护资源"两难"局面的一些表象,更深层次的原因应从体制、机制、法制的缺陷中探寻,最基础的前提就是要提高国土资源文化的软实力。新媒体时代下,国土资源文化建设通过互联网站、手机报、微博等新媒体手段及报纸、杂志等传统媒介平台进行传播,不断为国土资源事业的改革发展提供强大的精神动力和舆论支持。  相似文献   

17.
Modeling and assessment of bridge structure for seismic hazard prevention   总被引:7,自引:7,他引:0  
This study uses data from Mao-Luo-Hsi Bridge to model the bridge structure and a set of developed alarm and action values to formulate guidelines for bridge maintenance and seismic hazard prevention. The bridge model is improved by incorporating on-site ambient vibration measurement to perform modal analyses. Dynamic analyses of the bridge are implemented using the established 3D model subjected to uniform loading and seismic force, with or without consideration of soil interaction with the structure. The maximum displacements for different sections of the bridge are compared, and statistical regression analyses are used to explore their correlation. Information for bridge safety assessment is proposed, which can mitigate loss of property and lives due to bridge failure. Regression analyses of the maximum displacements between abutments D and E of the considered bridge in the axial, horizontal, and vertical directions under various seismic intensities are conducted, giving R 2 values of 0.9462, 0.9352, and 0.9010, respectively. The developed maintenance guidelines are reliable since all parameters from regression analyses have a 95% confidence interval excluding the zero value. The bridge alarm value and action value are determined for this bridge site at earthquake intensity scales of 4 and 5, respectively.  相似文献   

18.
To put on the map: according to the Oxford English Dictionary, whatever is so placed occupies “an important or prominent position” and is “of some account or importance.” In this brief commentary, I take the opportunity to reflect on several articles by medical/health geographers and others regarding our Public Health Disparities Geocoding Project and my research, as a social epidemiologist, on the myriad ways racism can harm health. In both cases, my work on these topics has been motivated by my desire, starting a quarter of a century ago, to put health inequities on the map: as a topic of public concern, research, and action. The insightful and informative points and questions raised by the geography-oriented articles underscore the importance of bringing the best of our respective disciplinary insights and expertise to illuminate the profound connections between social justice and public health, between our bodily truths and the body politic, so as to further the goal of embodying equity––in an ecologically sustainable world.  相似文献   

19.
Environmental and engineering problems of karst Geology in China   总被引:1,自引:0,他引:1  
Karst terrane is generally regarded as a fragile and vulnerable environment. Its underground drainage system can aggrevate both drought and flood problems; the lack of filtration in an underground conduit makes waste disposal more difficult; and the lack of soil cover in bare karstland can enhance deforestation. Moreover, karst terranes are quite often haunted by a series of engineering problems, such as water gushing into mines or transportation tunnels; leakage from reservoirs; and failure of building foundations. In China, there are more than 200 cases of karst collapse, which include many thousands of individual collapse points. Some of these are paleo and natural collapses, but most of them are modern collapses induced by human activities and they have caused serious damage. Many factors such as geologic structure, overburden thickness and character, lithologic features of karstified rock, and intensity of karstification are related to development and distribution of modern collapses. However, China's karst is mainly developed in pre-Triassic, old phase, hard, compact, carbonate rock. Consequently most modern collapses have occurred only in the overlying soil. So it is understandable that the fluctuation of the water table in the underlying karstified strata plays an important role in the process of collapse. Nevertheless, there are different explanations as to how the groundwater activities can induce collapse.  相似文献   

20.
Sedimentary pollen, charcoal and plant macrofossil analyses with high resolution and precision suggest a strong shift in vegetation composition during the early to mid‐Holocene transition in the upper mountain belt. At Piano mire (1439 m above sea level (a.s.l.), Ticino, Switzerland) forests were dominated by Abies alba during the early Holocene (prior to ca. 8000 cal. a BP). Abrupt collapses of A. alba at ca. 7800–7400 cal. a BP enabled the expansion of the light‐demanding pioneer Betula. Afterwards A. alba populations regained their previous abundance in the forests. Within the dating uncertainties of our record we assume that a unique combination of wet and cold years between 8400 and 7500 cal. a BP led to repeated lethal disadvantages for Abies. Our record of Abies oscillations is in good biostratigraphic agreement with the record that has been used to define the Misox cold event (Pian di Signano, 1540 m a.s.l.), which has been previously correlated with the 8200 cal. a BP event. Given the age estimates of the Abies collapses in our well‐dated record, our results suggest that additional efforts are needed to understand the linkage between the Misox and the 8200 cal. a BP event. They imply a high sensitivity of mountain vegetation far below the tree line (~800 m) to Holocene climatic changes of about 2°C in annual air temperature. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

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