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<正>KnowledgeaboutlandcoverandlandusehasbecomeincreasinglyimportantastheNationplanstoovercometheproblemsofuncontrolleddevelopment,deterioratingenvironmentalquality,lossofprimeagriculturallandsetc.Landuseandlandcoverdataareneededintheanalysisofenvironmentalprocessesandproblemstoknowiflivingconditionsandstandardsaretobeimprovedormaintainedatcurrentlevels. 相似文献
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Aviation constitutes about 2.5% of all energy-related CO2 emissions and in addition there are non-CO2 effects. In 2016, the ICAO decided to implement a Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) and in 2017 the EU decided on faster emission reductions in its Emissions Trading System (EU ETS), which since 2012 includes the aviation sector. The effects of these policies on the expected development of air travel emissions from 2017 to 2030 have been analyzed. For the sample country Sweden, the analysis shows that when emissions reductions in other sectors are attributed to the aviation sector as a result of the EU ETS and CORSIA, carbon emissions are expected to reduce by ?0.8% per year (however if non-CO2 emissions are included in the analysis, then emissions will increase). This is much less than what is needed to achieve the 2°C target. Our analysis of potential national aviation policy instruments shows that there are legally feasible options that could mitigate emissions in addition to the EU ETS and CORSIA. Distance-based air passenger taxes are common among EU Member States and through increased ticket prices these taxes can reduce demand for air travel and thus reduce emissions. Tax on jet fuel is an option for domestic aviation and for international aviation if bilateral agreements are concluded. A quota obligation for biofuels is a third option.Key policy insights
Existing international climate policies for aviation will not deliver any major emission reductions.
Policymakers who want to significantly push the aviation sector to contribute to meeting the 2°C target need to work towards putting in place tougher international policy instruments in the long term, and simultaneously implement temporary national policy instruments in the near-term.
Distance-based air passenger taxes, carbon taxes on jet fuel and quota obligations for biofuels are available national policy options; if they are gradually increased, and harmonized with other countries, they can help to significantly reduce emissions.
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Aviation is a fast-growing sector, releasing more carbon dioxide per passenger kilometre than other transport modes. For climate change researchers, work-related travel – including for conferences and fieldwork – is a major carbon-emitting activity. At the same time, many argue that climate scientists have an important role in curbing their own aviation emissions to align their practices with their assertions in relation to emissions reduction. We examine the tensions between competing professional demands in relation to flying; measure levels of flying by climate and non-climate researchers; assess influences on choices and attitudes; and consider how information provision and structural changes might enable changes in practice. Study 1 entails a large, international survey of flying undertaken by climate change (including sustainability and environmental science) researchers and those from other disciplines (N = 1408). Study 2 tests effects of varying information provision on researchers’ behavioural intentions and policy support to reduce flying (N = 362). Unexpectedly, we find climate change researchers – particularly professors – fly more than other researchers, but are also more likely to have taken steps to reduce or offset their flying. Providing information about the impacts of aviation increases behavioural intentions and support for institutional policies to reduce flying, particularly amongst more pro-environmental respondents. However, while attitudinal factors (e.g., personal norm) predict willingness to reduce flying, structural/social factors (e.g., family commitments, location) are more important in predicting actual flying behaviour. Recent initiatives to develop a low-carbon and more inclusive research culture within climate science and the broader research community thus need to be supported by broader policies and technologies to encourage and enable low-carbon and avoided travel. 相似文献
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川藏公路中段地质灾害现象的航空遥感研究 总被引:2,自引:0,他引:2
川藏公路巴塘至林芝段位于我国青藏高原东南部,该地区是现今地壳运动十分强烈的地区之一,地形起伏强烈,气候变化多样,因此地质灾害十分发育,川藏公路就穿过这样一个复杂的地区。为查明公路沿线的地质灾害分布情况,90年代初,地矿部航空物探遥感中心沿川藏公路进行了彩色红外航空摄影,比例尺为1∶6万。通过彩色红外航片的解译及野外实地观测,圈定出滑坡、泥石流及崩塌等灾害现象,并对这些灾害的强度、活动性及其对公路的影响进行分析,最后对灾害成因及治理方法提出了建议。 相似文献
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Understanding the geographical preferences of international tourists is critical for the tourism planning and marketing. However, it is not an easy endeavor to gather the corresponding information, given the absence of city-level tourism statistical data and high costs of participant survey. This paper characterizes the geographical preferences of international tourists using geo-tagged photos on social media (the Flickr in particular). Data are harvested for 333 prefecture-level cities in China from 2008 to 2013, and the intensity of photo sharing (IPS: the ratio between total number of uploaded photos and total area of the city/region) is used an indicator of tourist geographical preferences. IPS visualization shows the geography that tourism hotpots generally concentrate in regional capital cities and economically developed megaregions. More specifically, the East Asia and Oceania tourists exhibit more preferences towards the eastern coastal cities, while the Europe and North America visitors show increasing interest in exploring the western and northern places. Spatial regression is employed to quantify the local influential factors of tourists’ geographical preferences. It is found that international tourists usually consider the local economy, accessibility, infrastructure and cultural attractions when they choose their destinations in China. East Asia and Oceania visitors particularly appreciate the local economy and cultural attractions. Europe and North America tourists especially value the cultural attractions and local openness. The demonstrated methodological framework is not restricted to Flickr data, and it can be applicable to social media offer geo-tagging service. This paper is therefore believed to advance the applications of social media into geographical research. 相似文献
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Three different methods to analyse fine sediment deposits on a gravel bar using pictures are presented in this paper. A manual digitization and deposits zone delineation are performed as well as two different automated procedures. The three methods are applied on aerial pictures taken in 2006 by a drone from a height around 150 m above the study site. Two other sets of pictures taken in 2010 are also studied: the first set was obtained from the left side bank of the river at approximately 15m above the gravel bar whereas the second one was taken from a helicopter flying 600~m above the ground. These methods were used to estimate the surface of fine sediment deposits before and after flushing events. They yield similar results even if the first automated procedure is able to capture smaller patches of fine sediments. The total surface of fine sediment deposits seems to be similar before and after a flushing event, but the distribution appears quite different. Before a flushing event, a significant amount of fine sediment deposits are mixed with coarser sediments. After the flushing event, one can observe more large fine sediment deposits located on the downstream part of the secondary channel and at the channel margin. Most of the small fine sediment deposit patches were washed out. A short discussion is provided on the possible dynamics of fine sediment deposits over the gravel bar. 相似文献