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61.
“Of outstanding universal value”: The challenge of scale in applying the World Heritage Convention at national parks in the US 总被引:1,自引:0,他引:1
Helen Hazen 《Geoforum》2008,39(1):252-264
This paper explores the operation of the international World Heritage Convention in the national context of the United States. Although an early advocate of the national park idea and among the earliest proponents of the Convention, the US has shown increasing ambivalence towards the World Heritage Program since the mid-1990s. Through in-depth interviews with expert informants and a questionnaire survey of 406 visitors at four US World Heritage Sites, this study considers whether combining national and international conservation designations provides valuable reinforcement of conservation goals, or leads to unnecessary overlap and even challenges to sovereignty. The majority of my expert informants were supportive of the Convention, related to philosophical and practical benefits that they believed to be associated with the World Heritage label, although most identified few tangible influences of the World Heritage Program itself. Several noted hostility to the Program from a nationalist fringe, which fears international involvement in land use decisions. Such concerns were reflected in questionnaire responses, which revealed some distrust of the Convention and misunderstandings of its operation. I conclude that the scalar mismatch of implementing an international convention at the national scale inevitably involves challenges, but that country-specific factors are important in explaining why the Convention has been particularly controversial in the US. Education is integral to addressing these challenges, as well as reengagement with the Program by both the National Park Service and the federal administration. Intangible values associated with World Heritage mean that the Convention still enjoys considerable support in the US, providing a solid foundation for such a reengagement. 相似文献
62.
63.
As a complex social ecosystem network, the area along the Grand Canal has a prominent contradiction between the demand for economic development and the protection of natural resources, which means that there is an urgent need for ecological restoration and environmental protection. Using ArcGIS, Conefor, Linkage Mapper and other software platforms, this paper developed an integrated analysis framework, through loose coupling of the attribute-function-structure index system and a series of methods such as the least cost path, circuit theory and moving window search. Based on the framework, we resolve a series of scientific issues in developing regional ecological networks, such as the selection of ecological sources, the simulation of potential ecological corridors, the assessment of the importance of ecological sources and corridors, and the identification of key ecological nodes. Moreover, an overall conservation pattern of the regional ecological network is constructed. The results show that: 1) A total of 88 important ecological sources are identified in the study area. The patches with high centrality values are mainly concentrated in the southern mountainous area and the areas with abundant rivers and lakes. 2) A total of 138 important ecological corridors are identified, and they are not evenly distributed. Extremely important corridors mostly appear between important patches, and very important corridors are mainly distributed in the central area. 3) Fifteen ecological pinch points are extracted, and they are mainly concentrated in the northern part of the study area and eastern Zhejiang Province. The barriers are mostly concentrated in the southern and northern parts of the study area. 4) Combining the demands of ecological protection and socioeconomic development, we propose an overall ecological conservation pattern of “one axis, five sections, multiple cores and multiple nodes” to effectively guide future ecological restoration work. These results can provide a useful reference and spatial guidance for decision makers in terms of ecological restoration and cooperation on cross-regional ecological protection along the Grand Canal. 相似文献
64.
Nicholas E. Graham Konstantine P. Georgakakos Carlos Vargas Modesto Echevers 《Advances in water resources》2006
The Panama Canal relies on rain-fed streamflow into Gatun Lake, the canal’s primary storage facility, for operations—principally ship passage and hydropower generation. Precipitation in much of Panama has a strong negative relationship with eastern tropical Pacific sea surface temperature (SST) and this relationship is reflected in Gatun Lake inflows. For example, the correlation coefficient between wet season (July–December) inflow and NINO3 SST is −0.53 over the period 1914–1997. Operational capabilities to predict tropical Pacific SSTs have been demonstrated by several forecast systems during the past decade, and (as we show) such SST forecasts can be used to reduce the uncertainty of estimates of future inflows (compared with climatological expectations). Because substantial reductions in lake inflow negatively impact canal operations, we wondered whether these forecasts of future inflows, coupled with a method for translating that information into effective operational policy, might result in more efficient canal management. A combined simulation/optimization/assessment “virtual” canal system was implemented and exercised using operational El Niño forecasts over the period 1981–1998. The results show the following main points:
- (i)
- At current demand levels, the canal system is relatively robust (insensitive to flow forecasts) unless flows are substantially reduced (i.e., during El Niño episodes) or forecasts are extremely accurate. 相似文献
65.
Gary R. O'Brien Darrell S. Kaufman Warren D. Sharp Viorel Atudorei Roderic A. Parnell Laura J. Crossey 《Quaternary Research》2006,65(3):366-379
Holocene and modern travertine formed in spring-fed Havasu Creek of the Grand Canyon, Arizona, was studied to determine the factors governing its oxygen-isotope composition. Analysis of substrate-grown travertine indicates that calculated calcite-formation temperatures compare favorably with measured water temperatures, and include silt-rich laminae deposited by monsoon-driven floods. Ancient spring-pool travertine is dated by U-series at 7380 ± 110 yr and consists of 14 travertine-silt couplets of probable annual deposition. One hundred eighty high-resolution δ18O analyses of this mid-Holocene sample average −11.0‰ PDB. The average value for modern travertine is 0.5‰ lower, perhaps because mid-Holocene temperature was higher or there was proportionally greater summer recharge. δ18O cyclicity in the mid-Holocene travertine has average amplitude of 1.9 ± 0.5‰ PDB, slightly less than the inferred modern-day annual temperature range of Havasu Creek. The annual temperature range might have been reduced during the 14-yr interval compared to present, although other non-temperature factors could account for the muted annual variation. Silt-rich laminae within isotopically lower calcite in the modern and mid-Holocene travertine verifies the seasonal resolution of both samples, and suggests that similar temperature-precipitation conditions, as well as monsoon-generated summer floods, prevailed in the mid-Holocene as they do throughout the Grand Canyon region today. 相似文献
66.
京杭大运河的完全价值观 总被引:4,自引:0,他引:4
从理论和现实背景出发, 提出对京杭大运河价值的初步认识: 京杭大运河具有四大基本价值: (1) 作为文化 遗产的价值, 起到彰显民族身份和促进文化认同的作用; (2) 作为区域城乡生产与生活的重要保障, 具有输水、航运 和灌溉等现实功能的价值; (3) 作为区域生态基础设施的价值, 是保障国土生态安全的关键性格局; (4) 运河还具有 作为潜在的休闲通道的价值, 是国民身心再生和教育的战略性资源。强调只有用完全的价值观充分认识运河廊道, 并处理好现实的功能需要与这些价值间的相互关系, 才能保护和利用好运河遗产及其相关资源, 使之在当代发挥 应有的作用。在此基础上提出以建设遗产廊道的方式、结合南水北调和东部生态安全格局及中国南北生态休闲廊 道的建设, 将保护与利用京杭大运河作为国家战略。当务之急是: (1) 应用“反规划”理念进行运河的整体保护规划; (2) 展开资源摸底, 全面掌握大运河遗产廊道资源情况; (3) 制定整体性的管理和发展战略; (4) 以申报世界遗产南 水北调工程为契机, 建立大运河区域间协作机制。任何单一的价值观(如从单一的输水功能考虑) 和单一的工程措 施, 都将给中国大地上这一独特的文化景观和与之相联系的历史文化、生态及社会经济系统带来不可挽回的遗憾。 相似文献
67.
68.
Vu Thi Hong Hanh 《GeoJournal》2006,66(3):165-186
Since the city’s founding back in 1698 on the old Khmer city of Prei Nokor, rivers and canals have always been Ho Chi Minh
City’s (HCMC’s) primary means of transportation. Despite the decline of the utilization of the city’s abundant waterways due
to the increasing development of modern aerial services and more convenient roads, the HCMC’s canal-based urban form, with
its water-based socio-economic structures that include port-boat-market activities and canal handcraft villages, still processes
a rich cultural and religious diversity that dates back to the history of the city itself. Currently, developments in the
city’s transportation systems are having a damaging impact on the canals’ cultural background. Rather than being recognized
as a significant cultural asset that identifies the city, the canal system has been physically reorganized as the city’s drainage
system and valued as only a supplementary landscape element; canal communities have been evicted, and canal built fabric has
been removed due to recent canal-side transportation developments. To revitalize the urban cultural identity that is possessed
by the canal system and to enrich it as a contemporary valuable layer in the city’s dynamic regional development, it is critical
to implement cultural conservation and tourism in the development of canal-side transportation and supplementary projects
in the canal vicinity. 相似文献
69.
四川乐山大佛风化的初步探讨 总被引:5,自引:1,他引:5
四川乐山大佛石刻是我国重要的“世界文化与自然遗产”之一,石刻表面毁损非常严重。本文通过(1)检测石刻所在地区粉砂岩的样品成分(XRFS)获悉,SiO2含量高达84%;(2)安装微侵蚀测量装置(MEM)直接测得粉砂岩的表面侵蚀速率大约为0.216~0.305mm/a;结合(3)粉砂岩表面的相对硬度测试比较等途径,对石刻毁损的表面过程机制进行了初步的综合分析。结果表明,由于粉砂岩结构松散,经水浸后表面硬度急剧下降,而且当地的水、气等条件适宜于生物繁衍等特点,石刻风化毁损的原因主要在于水、生物等环境因素对粉砂岩胶结物有强烈的破坏作用。 相似文献
70.
1 INTRODUCTION At present, most of the instruments used for sampling sediment loads at the canal intakes along the Yellow River in Shandong Province are horizontal samplers. These kinds of samplers cannot sample the suspended load 0.3 m from the riverbed. More recently use of bottle samplers has allowed sampling of the sediment load up to 0.1 m from the riverbed. However, bottle samplers are not able to measure suspended loads with high sediment concentrations and coarse sediment particl… 相似文献