共查询到20条相似文献，搜索用时 31 毫秒
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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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Pablo S. Bose 《The Professional geographer》2013,65(1):145-146
Contemporary cartographic research on mapmaking and map use has a broad mandate and, as a consequence, researchers need a broad suite of methods. Consistent with research developments in other geographic subdisciplines, cartographic researchers now use qualitative methods. They offer the advantage of bringing research closer to the problem-solving realms of mapmakers and map users. Our purpose here is to discuss an array of qualitative methods for mapmaking and map use. Questionnaires, interviews, and protocol methods are used to gather verbal data about mapmaking and map use. Ethnographies produce data from direct observation of mapmakers and users. Maps also are sources for document analysis. We use examples of published cartographic research to elaborate on each of these methods. 相似文献
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The Dongting Lake is located in the south beach of the middle reaches of the Yangtze River. Its catchment, with an area of 262,823 km2 or about 12% of the total Yangtze River catchment, is situated between 28o43?29o32扤 and 112o54?113o8扙, and crosses Hubei and Hunan provinces in administrative division. The main tributaries include Xiangjiang, Zishui, Yuanjiang, Lishui rivers (4 Tributaries) and some local rivers, such as Miluo River, Xinqiang River and other little streams. In the nor… 相似文献
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1 IntroductionIt is well known that the major problem of water resources at present is water shortage in the North China Plain. The development of agricultural production certainly increased the water consumption, so level of groundwater table declined year by year. Crop use water directly from soil water, while rainwater, surface water, and groundwater should be firstly transformed and changed into soil water and then be used by crops. Therefore, water interactions, water balance and soil w… 相似文献
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This research paper concentrates on creating easy and stress-free classroom in English teaching.The paper talks that teachers should adopt pupil-centered teaching methodology and employ every means of teaching such as listening and speaking;acting;singing songs;playing games;role-playing. 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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Climatic hazards are a key feature of life. It is vital that teachers are knowledgeable about these phenomena in order to develop their students’ understanding of them. This study used a mixed methods approach to examine the accuracy and depth of preservice primary teachers’ (n = 430) knowledge of tropical cyclones. The findings suggest that prospective primary teachers hold alternative conceptions about the causes, spatial distribution, and impacts of these phenomena and that their explanations of processes lack structural complexity and integration. Issues raised by these findings and implications for teachers’ geographical knowledge and their professional standards and preservice teacher education are discussed. 相似文献
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James L. Wilson 《The Professional geographer》2013,65(4):624-626
In this article, we examine graffiti abatement policies and programs in three West Coast U.S. cities: Portland, San Francisco, and Seattle. Through this analysis, several similarities in the graffiti abatement efforts of each city emerged. Since the 1990s, graffiti abatement efforts in these cities have become increasingly formalized and coordinated. By the early 2000s, the cities of Portland, San Francisco, and Seattle adopted zero-tolerance approaches toward handling graffiti and those caught making graffiti. City governments have placed increasing responsibility for cleaning up graffiti on private property onto property owners. Despite the increased coordination and effort, annual abatement estimates are hard to obtain because tracking spending on graffiti abatement across agencies and bureaus is difficult and often the cities do not comprehensively compile these data. 相似文献
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Zhou Bin Xu Jiang Peng Shoujian Yan Fazhi Yang Wei Cheng Liang Ni Guanhua 《Natural Resources Research》2020,29(3):1617-1637
Natural Resources Research - As one of the most serious dynamic disasters in underground coal mining, coal–gas outburst (CGO) leads to very high casualties and economic losses. To research... 相似文献
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Cities are the key areas for human beings to achieve sustainable development goals in the future. Estuarine cities are a special type of coastal city in urgent need of a clear definition. This paper proposed that estuarine cities are cities developed on the coast where rivers and oceans meet and defined four connotations, including the intersection of rivers and marine water systems, the coordinated development of land and oceans, the location advantages of connecting rivers and seas, and the im... 相似文献
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A fossilised paleoanthropological skull was discovered in November 1987, in the guily-head cliff on the east bank of Wenyu River near Xinza village, Yuling - town (hence the name Yuling-Man), Lingbao country, Henan Province, China. The skull, dated to an absolute U-isotope (U234 to U238 ) age of B. P. 156000 ± 13000 years, was found in the upper portion of the alluvial statum of the mid-Pleistocens Series, together with pateoliths of the Kehe Cutture System in the mid-late Paleolithic Periods. Although much research has been nomied out in this area, this is the first fossilised paleoanthropological skull in have been found. Therefore, this project, funded by the Natural Science Foundation/Henan Scientific Committee, is making new contributions to paleoanthropological research in China. 相似文献
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The rich, fossiliferous Triassic sediments exposed in the Virginia Solite Quarry include a 34-mm-thick “insect layer” that
is notable for detailed preservation of soft-bodied invertebrate and vertebrate remains. We describe this unique Konservat-Lagerst?tte and use sedimentologic and geochemical analyses to interpret the environmental conditions necessary to preserve such delicate
fossils. This work is among the first attempts to apply detailed geochemical/stratigraphic analysis to the study of Lagerst?tten and we report on a 332-mm-thick section that includes the insect layer and the rocks immediately below and above it. Our
analysis successfully constrains various aspects of the depositional and diagenetic history of the Lagerst?tte and permits a detailed analysis of changing conditions prior to, during, and after deposition. Geochemical and sedimentologic
analyses of the insect layer and surrounding lithologies reveal a change from siliciclastic-dominated layers (Unit 1) to dolomite-siliciclastic
laminites above (Unit 2 and the insect layer), separated by a boundary dolostone layer that is traceable for over 200 m. We
interpret this sedimentary shift as the initial stages in the transgression of a shallow, saline, alkaline rift-basin lake
over lake margin deposits. The absence of bioturbation by plants and benthic organisms, as well as a lack of predation on
the insects, is not explained by significant water depth, but is instead more reasonably considered a result of the chemistry
of the water at the lake margin, affected by groundwater seeps, which provided F-, Mg-, and Ca-rich fluids. Although the initial
conditions of preservation are remarkable, it is equally impressive that the fossils survived extensive diagenesis, e.g. dissolution
of quartz and coarsening of dolomite. 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
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《地理学报(英文版)》1999,(4)
TherehavebeenseveraldozensofyearssincethedevelopmentandstUdyofthemetropolitanareasindevelopedcountries.Atpresent,somemetropolisesaresteppingintothestageofmetropolitandevelopmentinChina.Thegeneraltrendisunavoidablethatbuilt-upareaexpandsandrurallandturnsintourbanones.Butunderthedriveofgoingmerelyaftereconomicbenefit,man}.'collectivesandindividualsillegallyoccupycultivatedlandandgreenbelts,whichintensifiesurbanenvironmentalpollution,wasteslandresourceandmakesthebuilt-upareaexpanduncontrollabl}'… 相似文献