共查询到20条相似文献,搜索用时 31 毫秒
1.
Silviu Constantin Theofilos Toulkeridis Oana Teodora Moldovan Marcos Villacís Aaron Addison 《自然地理学》2019,40(1):28-51
Current knowledge of caves and karst regions of Ecuador is scarce and broadly limited to discrete areas such as that of the Galápagos volcanokarst. In continental Ecuador, carbonate karst mostly outcrops in the Amazonian basin and accounts for 5–10% of the surface of the country. However, owing to the difficulties of access within the Amazonian rainforest, most surface and subterranean karst is yet to be revealed. In this review, we present an updated map of the solutional karst of Ecuador based on the most recent geological surveys and our own research. We describe the principal karst regions of Ecuador from the Amazonian basin (Napo and Santiago) as well as the Galápagos pseudokarst. We show that Ecuador karst research may be of considerable importance for both basic and applied research owing to its geographical position and intrinsic vulnerabilities. We discuss the main challenges of karst-related research in Ecuador, such as paleoclimatic studies, subterranean biodiversity, and archeology. We discuss the main vulnerabilities and hazards related to karst uses in Ecuador, considering the paramount importance of tourism for the country. 相似文献
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As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries, the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ) of China plays an important role under the Belt and Road Initiative. With the rising attention on OETCZ, studies regarding OETCZ have also increased. However, there is a lack of studies reviewing this topic’s progress, challenges and future directions. This paper employs a systema... 相似文献
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Review of and prospects for China’s human and economic geography 总被引:1,自引:1,他引:0
The “High-Level Forum of the Development of China’s Human Geography Under the Background of Change” was held in Beijing on January 22-23, 2016. More than 30 professors attended this forum. At this conference, they discussed the major progress made towards developing China’s human geography, as well as the existing problems, limiting factors, opportunities, international collaborations, emerging directions, and prospects in the development of this discipline. In recent years human geography has boomed, generating many important opportunities for its development. Establishing an academic community for joint research on major research issues and collaborative innovation is a promising and important route to take. We should embrace both domestic and international characteristics, to promote China’s human geography onto the world stage. Meanwhile, the cultivation of various scholarly talents is also of great value to enrich and advance the discipline. 相似文献
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The two concepts of “liudong renkou(floating population or FP)” and “renkou liudong(mobility of the floating population or MOFP)”, along with relevant data based on these two concepts, have long been used extensively in China’s research and policy making, playing a central role in Chinese studies of migration. Unlike the concepts of “migrant” and “migration” in the international literature, which are focused on people’s spatial mobility, “liudong renkou” and “renkou liudong” are identified and m... 相似文献
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Amin Ettehadtavakkol Christopher Jablonowski Larry Lake 《Natural Resources Research》2017,26(2):177-190
Uncertainty complicates the development optimization of oil and gas exploration and production projects, but methods have been devised to analyze uncertainty and its impact on optimal decision-making. This paper compares two methods for development optimization and uncertainty analysis: Monte Carlo (MC) simulation and stochastic programming. Two example problems for a gas field development and an oilfield development are solved and discussed to elaborate the advantages and disadvantages of each method. Development optimization involves decisions regarding the configuration of initial capital investment and subsequent operational decisions. Uncertainty analysis involves the quantification of the impact of uncertain parameters on the optimum design concept. The gas field development problem is designed to highlight the differences in the implementation of the two methods and to show that both methods yield the exact same optimum design. The results show that both MC optimization and stochastic programming provide unique benefits, and that the choice of method depends on the goal of the analysis. While the MC method generates more useful information, along with the optimum design configuration, the stochastic programming method is more computationally efficient in determining the optimal solution. Reservoirs comprise multiple compartments and layers with multiphase flow of oil, water, and gas. We present a workflow for development optimization under uncertainty for these reservoirs, and solve an example on the design optimization of a multicompartment, multilayer oilfield development. 相似文献
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The temporal and spatial relationship between NDVI and climatological parameters in Colorado 总被引:3,自引:1,他引:3
1 Introduction In recent years, many researchers have demonstrated that there are essential and evident correlations between NDVI and climatological parameters (temperature and precipitation). The analysis of correlation between climate forces and time-integrated NDVI over US Northern and Central Great Plains suggested that spatial and temporal variation of precipitation and potential evapotranspiration and growing degree days in growing season are the most important control on grassland… 相似文献
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This study aims to investigate the spatiotemporal trends in snow depth (SD) and snow cover extent (SCE) for Arctic lands, excluding Greenland, for the period 1948–2006. The investigation not only delineates how the Arctic regions are manifesting significant annual trends in both SD and SCE, but also provides a comprehensive understanding of their historical context. To achieve these objectives, the combined resources of the hydrological and biogeochemical model (CHANGE), National Oceanic and Atmospheric Administration (NOAA) weekly SCE data, and in situ observations of SD were used. Most regions in the Arctic exhibited a significant negative trend in SD over the 59 years of study. The magnitude of the negative trend was stronger in North America than in Eurasia, where the decrease became more significant, starting from the late 1980s, coinciding well with the temperature rise during that time. During the same period, the warming temperature caused a prominent decrease in deeper SDs (i.e., >35 cm), so that the corresponding SCEs exhibited negative anomalies, with the greatest declines being observed at SDs > 55 cm. In contrast, the SCEs for SD ≤ 35 cm showed increased anomalies during the most recent two decades. The increased anomalies signify a sequential result induced by the decrease in the SCEs with deeper SDs, rather than the expansion of snow to snow-free regions. These changes resulted in a northward shift of the shallow SD line, which took place to a highly significant degree in North America. These results suggest that the Arctic SCE and SD will undergo more intense changes in response to the future climate warming. 相似文献
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This essay examines the recent controversy surrounding ‘Safe Schools', a federally-funded education program designed to reduce anti-lesbian, gay, bisexual, transgender and intersex (LGBTI) bullying in Australian schools. Although LGBTI students are known to experience homophobic, biphobic and transphobic verbal and physical abuse at school, opponents of Safe Schools have argued that the Program is both unnecessary and potentially harmful. In the essay, we argue that geographers have valuable contributions to make to this debate, particularly by revealing the ways in which sexuality and gender shape young people's experiences of school spaces. 相似文献
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Rural decline has become a global problem. To address this issue, the division of rural functions and identification of driving factors are important means of rural revitalization.Taking the town area as a unit, this study conducts a division and evolution analysis of rural regional functions in Jiangsu province in coastal China by constructing an evaluation system using the spatial econometric model to diagnose endogenous and exogenous driving factors of rural multifunction formation. The resul... 相似文献
10.
This paper explores the evolution of land use and natural resource management strategies over the past twenty to fifty years in a remote Sahelian region. The empirical example is Karagou village in SE Niger. Building on an in-depth survey from 1992 and a targeted, follow-up analysis of contemporary land use strategies in 2011, the change process is scrutinized.The analysis uses the conceptual lenses of land systems science, human–environmental timelines, and the notion of multiple exposures. Enabling and constraining conditions for local livelihoods in terms of the resource base (landscape, water, and population) are described. Results characterize how land use strategies have developed and how local people opportunistically use different landscape elements such as dune landscapes, valley bottoms (bas-fonds) and oases (cuvettes). Major concerns are rainfall variability, saturation of cropland, and perceived dwindling groundwater resources. It is concluded that the land use and livelihood strategies have remained remarkably stable in the face of the changing socio-ecological fringe conditions, but that this situation may hamper a sustainable transformation. 相似文献
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Journal of Geographical Sciences - The urban-rural transformation from dichotomy to integration is a gradual process. Like rural areas in many countries, Chinese rural society is experiencing a... 相似文献
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Mark Davidson 《Urban geography》2013,34(5):657-676
Urban parks have long been used by policy makers to achieve specific policy goals. In recent years, two sets of policy goals have become commonly associated with park planning. The first set of goals can be characterized as being neoliberal, where parks have been built and reformed to generate certain economic and governmental outcomes. The second set of policy goals is associated with sustainability, where parks have been utilized as tools in such things as the mitigation of climate change and community building. The aim of this paper is to examine how these two sets of policy goals have come to coexist. The paper draws upon the case study of Sydney Olympic Park, a self-proclaimed exemplar of both entrepreneurial urban development and sustainability. The paper traces out the functional and institutional changes at the Park in order to read the relationship between neoliberal and sustainability policy goals. While predictable inconsistencies are found between the two sets of policy goals, the paper argues in conclusion that their contradictions have not generated a necessity to resolve their antagonistic relations. [Key words: Sydney, Olympic Games, neoliberalism, sustainability, parks.] 相似文献
14.
Determining how to achieve sustainable development and protection of historical districts is a worthwhile research topic. As a vital way to update urban space, tourism development in historical districts is an effective tool for redistributing urban functions and increasing urban vitality. This paper takes the Insa-dong in South Korea as a case study for the evaluation of tourist satisfaction in historical districts, based on 550 questionnaires. The questionnaire contains 33 evaluation indicators, and the subjects' subjective judgment and satisfaction with Insa-dong are measured in the form of the Likert scale. Using SPSS to analyze tourists’ satisfaction with historical districts, this studyfinds that: (1) The tourist satisfaction evaluation of Insa-dong includes six dimensions in total: “Embodiment of historical elements”, “The blend of tradition and modernity”, “Industry distribution and type”, “Consumer demand”, “ Street layout and function” and “Landscaping”. (2) “The blend of tradition and modernity” has the highest weight while “Industry distribution and type” has the lowest one in the analysis of factors influencing overall satisfaction. (3) The analysis of the common factor weights and the common factor satisfaction levels shows that “The blend of tradition and modernity” and “Street layout and function” are the parts that need to be improved. “Consumer demand” also has a lot of room for promotion. The research results will be beneficial for enhancing the tourist experiences of historical districts and they provide a theoretical basis and practical experience reference for effective protection and sustainable development of historical districts. 相似文献
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Antigua and Barbuda is rapidly developing a tourism industry built around a marketed perception of a healthy marine and coastal environment. Yet economic indicators suggest that Antigua and Barbuda is overexploiting its marine resources, particularly its fish and coral reef communities. Although its marine resources remain relatively healthy, Antigua and Barbuda will jeopardise the ecological basis of its economic growth and sustainability if current exploitation rates continue. We compare the current situation and economic trends of Antigua and Barbuda's tourism and commercial fishery industries to those of Jamaica and other OECS member states. Jamaica is suggested as a cautionary example of the potential socioeconomic and ecological impacts caused by resource overexploitation and mismanagement within the various economic sectors. Antigua and Barbuda is at a crossroads. The 'Jamaica path' leads to large-scale resource depletion, fishery collapse, and a mass tourism industry that can operate independent of a healthy environment. Alternatively, it can pursue a path that seeks to conserve its marine resources. Antigua and Barbuda will be better able to protect its sustainability both for commercial fishing interests and its growing high-end destination tourism industry. To this end, Antigua and Barbuda has developed a network of marine-protected areas along the northeastern coast of Antigua, an area popular with both fishers and tourists. 相似文献
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This paper reviews the past history of comparisons between lacustrine records of chironomid-inferred summer temperatures (CI-T) and peat bog-derived records of surface wetness (BSW), and develops a new summer temperature record for the mid-late Holocene for Northern Britain from Bigland Tarn, Cumbria. The CI-T reconstruction is well dated, and corresponds well with the only two other CI-T records for Britain. Comparisons are made with BSW records from northern Britain, which show consistent similarities over centennial to millennial timescales, demonstrating that at this resolution cooler summers equated with a wetter climate, at least during the mid- to late-Holocene. 相似文献
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The comprehensive evaluation of China's urbanization and effects on resources and environment 总被引:11,自引:3,他引:8
This paper constructs a comprehensive evaluation index system for the urbanization level in China in terms of four aspects
of urbanization connotation: population, economy, society, and land. A comprehensive measurement is carried out for the Chinese
urbanization between 1981 and 2006 based on the Entropy method. The results show that the comprehensive level of urbanization
in China has a continuous increase with the major features of economic growth and a rapid evolution of the geographical landscape,
followed by population urbanization and then social urbanization of health care standard; the distinguished evolutional characteristics
can also be found in each of the subsystems. The integrated evolution of urbanization has a profound effect on the resources,
energy and the environment, making the land resources and energy security situation under severe pressure. The environment
pressure is also increased further. 相似文献