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971.
This study provides insight into the potential of experiment-based policy making to address complex environmental challenges. The investigation shows the usefulness of making an analytical distinction between incremental and synoptic policy experiments to understand successful change over time. Incremental refers here to gradual adjustment of policies in a specific context, synoptic to radical change of policies on a large scale. Success is understood in terms of drawing lessons and realising policy goals, enabling diffusion and improving environmental status. This unique study, including both the initial investigation and a follow-up 10 years after, analyses the dynamics that emerged from seven empirical cases to identify factors affecting the design and success of these two types of experiments. We studied three incremental experiments and four synoptic experiments in the Dutch fen landscape to learn from their practical experiences. This densely populated and commercially used landscape is vulnerable to environmental pressure such as precipitation peaks, sea level rise and droughts. Initiators of the incremental experiments were able to change land-use management practices, albeit staying relatively close to the status quo. In contrast, while initiators of the synoptic experiments expressed higher ambitions in terms of change, these experiments tended to experience stagnation and difficulties in implementation and diffusion. Observations reveal that experiment-based policy change may crucially depend on capacity to deal with stakeholder dynamics and to embed experiments within multi-level institutional settings. 相似文献
972.
乌吉铁路沿线沙害分析及综合治理途径 总被引:3,自引:0,他引:3
乌达至吉兰泰运盐铁路穿越乌兰布和沙漠西南缘,全长130km,沙害极为严重。主要危害特点:由于修建铁路及通车以来人为经济活动的加剧,破坏了原有植被,导致沙化,危害铁路;风沙流是危害乌吉铁路的主要形式;由于风的多向性,使风沙作不规则的往复式摆动,造成铁路积沙;风沙危害严重地段集中在35~40km,47~52km,69~83km和99~105km等区间。通过对该线沙害程度、特点及自然因子的分析,提出"以封为主","封、飞、造"、"固、阻、输(导)"相结合的综合治理措施。 相似文献
973.
东营市短期气候预测系统设计及应用 总被引:1,自引:0,他引:1
东营市短期气候预测系统使用逐步回归、最优子集回归、BP人工神经元网络和多因子EOF迭代4种因子预报模型,以及3个以均生函数为基函数的多步预测模型,并通过集成得出预报结论。因子普查时,采用滚动式相关分析方法,保证了入选因子的稳定性。 相似文献
974.
The use of scenarios as the basis for combined assessment of climate change mitigation and adaptation 总被引:1,自引:0,他引:1
Detlef P. van Vuuren Morna IsaacZbigniew W. Kundzewicz Nigel ArnellTerry Barker Patrick CriquiFrans Berkhout Henk HilderinkJochen Hinkel Andries HofAlban Kitous Tom KramReinhard Mechler Serban Scrieciu 《Global Environmental Change》2011,21(2):575-591
Scenarios are used to explore the consequences of different adaptation and mitigation strategies under uncertainty. In this paper, two scenarios are used to explore developments with (1) no mitigation leading to an increase of global mean temperature of 4 °C by 2100 and (2) an ambitious mitigation strategy leading to 2 °C increase by 2100. For the second scenario, uncertainties in the climate system imply that a global mean temperature increase of 3 °C or more cannot be ruled out. Our analysis shows that, in many cases, adaptation and mitigation are not trade-offs but supplements. For example, the number of people exposed to increased water resource stress due to climate change can be substantially reduced in the mitigation scenario, but adaptation will still be required for the remaining large numbers of people exposed to increased stress. Another example is sea level rise, for which, from a global and purely monetary perspective, adaptation (up to 2100) seems more effective than mitigation. From the perspective of poorer and small island countries, however, stringent mitigation is necessary to keep risks at manageable levels. For agriculture, only a scenario based on a combination of adaptation and mitigation is able to avoid serious climate change impacts. 相似文献
975.
1 INTRODUCTION Soil erosion is serious in Western China. With the implementation of a development strategy for western China, soil and water conservation and ecological restoration in western China earn more attention because economic development requires parallel efforts on ecological restoration. To protect the ecology of the upper reaches of the Yangtze River, integrated management of sediment and ecological restoration are being conducted in Sichuan Province. The Yufeng Watershed… 相似文献
976.
从海洋战略的整体性和海上利益拓展的长远性来看,大西洋海域对于中国未来的海洋战略具有重要意义。文章基于对大西洋战略意义和当前战略形势的分析,提出拓展大西洋战略空间的建议,从经济贸易、海上安全、外交合作和科研调查等方面对其战略目标进行分析。基于此,进一步探索大西洋战略的实施路径,对我国在大西洋的已有基础进行梳理和剖析,同时从深化与大西洋国家的海洋经济与贸易合作、推进大西洋海洋科考、加快大西洋国际海底矿区的申请步伐、适度加强在大西洋海上力量的存在和积极参与国家管辖范围以外海洋生物多样性保护公约的谈判5个方面提出了拓展大西洋战略空间的政策建议。 相似文献
977.
World-wide, people and governments are gradually becoming more aware of the potential environmental, economic and health effects of climate change and the need for governments to take action to mitigate such impacts. This was emphasised by the creation of the United Nations Framework Convention on Climate Change (UNFCCC), signed at the Rio Earth Summit in 1992. There has been much discussion on the greenhouse policy response of the commonwealth government of Australia, especially its stance taken at Kyoto in December 1997. Despite the recent nationalisation of Australia's state energy markets, due to Australia's federal political structure, much of the policy responsibility for energy and environmental issues rests with the states. Given these circumstances it is surprising that there has been relatively little academic focus on the energy policies of the states. This paper attempts to partially fill the policy analysis 'gap' by investigating the present environmental aspects of the energy policies of NSW and Victoria, implemented since the signing of the UNFCCC in 1992. NSW and Victoria are Australia's most populous states and are responsible for the bulk of the nation's greenhouse gas emissions with two very distinct policies. 相似文献
978.
The extreme values of wave climate data are of great interest in a number of different ocean engineering applications, including the design and operation of ships and offshore structures, marine energy generation, aquaculture and coastal installations. Typically, the return values of certain met-ocean parameters such as significant wave height are of particular importance. There exist many methods for estimating such return values, including the initial distribution approach, the block maxima approach and the peaks-over threshold approach. In a climate change perspective, projections of such return values to a future climate are of great importance for risk management and adaptation purposes. However, many approaches to extreme value modelling assume stationary conditions and it is not straightforward how to include non-stationarity of the extremes due to for example climate change. In this paper, various non-stationary GEV-models for significant wave height are developed that account for trends and shifts in the extreme wave climate due to climate change. These models are fitted to block maxima in a particular set of wave data obtained for a historical control period and two future projections for a future period corresponding to different emission scenarios. These models are used to investigate whether there are trends in the data within each period that influence the extreme value analysis and need to be taken into account. Moreover, it will be investigated whether there are significant inter-period shifts or trends in the extreme wave climate from the historical period to the future periods. The results from this study suggest that the intra-period trends are not statistically significant and that it might be reasonable to ignore these in extreme value analyses within each period. However, when it comes to comparing the different data sets, i.e. the historical period and the future projections, statistical significant inter-period changes are detected. Hence, the accumulated effect of a climatic trend may not be negligible over longer time periods. Interestingly enough, such statistically significant shifts are not detected if stationary extreme value models are fitted to each period separately. Therefore, the non-stationary extreme value models with inter-period shifts in the parameters are proposed as an alternative for extreme value modelling in a climate change perspective, in situations where historical data and future projections are available. 相似文献
979.
980.
《Chemie der Erde / Geochemistry》2002,62(2):210-223
Society could sustain the impact of climate change by adapting to the change and mitigating risks from adverse effects of increasing changes, so that it can continue maintaining its prospect and improving wellbeing. Nevertheless, climate change is more or less affecting society's functions at different scales, including both individuals and communities. In this review, we discuss the relationship between society and climate change in China from the aspects of the needs at different socioeconomic developing stages. The relationship as well as the current spatial pattern and future risks of the climate change impacts on societies are summarized. The complexity of social and climatic systems leads to the spatial heterogeneity of climate impacts and risks in China. To more effectively leverage increasing knowledge about the past, we advocate greater cross-disciplinary collaboration between climate adaption, poverty alleviation and Nature-based Solutions (Nbs). That could provide decision makers with more comprehensive train of thoughts for climate policy making. 相似文献