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991.
Practical applications of surface wave inversion demand reliable inverted shear‐wave profiles and a rigorous assessment of the uncertainty associated to the inverted parameters. As a matter of fact, the surface wave inverse problem is severely affected by solution non‐uniqueness: the degree of non‐uniqueness is closely related to the complexity of the observed dispersion pattern and to the experimental inaccuracies in dispersion measurements. Moreover, inversion pitfalls may be connected to specific problems such as inadequate model parametrization and incorrect identification of the surface wave modes. Consequently, it is essential to tune the inversion problem to the specific dataset under examination to avoid unnecessary computations and possible misinterpretations. In the heuristic inversion algorithm presented in this paper, different types of model constraints can be easily introduced to bias constructively the solution towards realistic estimates of the 1D shear‐wave profile. This approach merges the advantages of global inversion, like the extended exploration of the parameter space and a theoretically rigorous assessment of the uncertainties on the inverted parameters, with the practical approach of Lagrange multipliers, which is often used in deterministic inversion, which helps inversion to converge towards models with desired properties (e.g., ‘smooth’ or ‘minimum norm' models). In addition, two different forward kernels can be alternatively selected for direct‐problem computations: either the conventional modal inversion or, instead, the direct minimization of the secular function, which allows the interpreter to avoid mode identification. A rigorous uncertainty assessment of the model parameters is performed by posterior covariance analysis on the accepted solutions and the modal superposition associated to the inverted models is investigated by full‐waveform modelling. This way, the interpreter has several tools to address the more probable sources of inversion pitfalls within the framework of a rigorous and well‐tested global inversion algorithm. The effectiveness and the versatility of this approach, as well as the impact of the interpreter's choices on the final solution and on its posterior uncertainty, are illustrated using both synthetic and real data. In the latter case, the inverted shear velocity profiles are blind compared with borehole data.  相似文献   
992.
The effects of four climate change scenarios for the Netherlands on the distribution of the shipworm upstream of the Rhine-Meuse estuary are described. Global warming will cause dry and warmer summers and decreased river discharges. This will extend the salinity gradient upstream in summer and fall and may lead to attacks on wooden structures by the shipworm. Scenarios including one or two degree temperature increases by 2050 compared to 1990 with a weak change in the air circulation over Europe will lead to an increased chance of shipworm damage upstream from once in 36 years to once in 27 or 22 years, respectively; however, under a strong change in air circulation, the chance of shipworm damage increases to once in 6 or 3 years, respectively. The upstream expansion of the distribution of the shipworm will also be manifested in other northwest European estuaries and will be even stronger in southern Europe.  相似文献   
993.
This paper examines the potential relationships between the ecosystem services provided by the coastal and marine environment and the designation of marine protected areas. The hypothesis is that relationships exist between the provision of ecosystem services and the features protected by marine protected areas. It is considered that protection will maintain these features in good ecological condition and in some cases will restore ecological functioning with positive effects on the delivery of ecosystem services, as pressures upon the protected features are reduced. As the number of marine protected area designations grows, system-wide effects to communities from improvements in delivery of a range of ecosystem services may be realised. This paper provides a comparative analysis of the jurisdictional marine protected area policies proposed by the English, Welsh and Scottish Governments. It presents structured assessment matrices developed from the literature and expert opinion, of ecosystem service provision by marine protected habitats and species and applies the findings to a range of existing UK marine protected areas to demonstrate its relevance. The approach and case study findings are discussed within the wider context of marine ecosystem services and marine protected area management.  相似文献   
994.
The geological storage of carbon dioxide (CO2) offers notable potential, as part of larger carbon dioxide capture and storage (CCS) processes, to be a significant climate change mitigation technology. This paper challenges the argument often put forward that, due to the greater distances from centres of population, it will be ‘easier’ to garner public and stakeholder support for offshore CO2 storage than onshore. Based on the results of research interviews carried out with stakeholders and informed publics in Scotland, challenges for public and stakeholder acceptance of sub-seabed CO2 storage that may require further policy attention are identified. Whilst existing policy for sub-seabed CO2 storage is cognisant of the need for societal engagement, it may be the case that these regulations may need further reinforcement to ensure future developments are able to address social acceptability issues as fully as possible. The value of taking into account social as well as physical characteristics at the site selection phase, the need for mechanisms to take seriously stakeholder conceptions of uncertainty, and the importance of extending social engagement beyond risk communication are discussed.  相似文献   
995.
996.
The paper considers the extent to which social–ecological systems research might contribute to an improved understanding of the social and environmental impacts of teleconnections inherent in economic globalisation. Recognising the importance and specificity of regional interconnections, wherein actions in certain parts of the world impact quite specifically on the sustainability of certain other spatially distant places and systems, the paper reflects on the social and environmental implications of increasingly interconnected agri-food systems and intersecting global commodity chains. Key elements of social–ecological systems approaches, which have purported relevance to research on globalisation, are critically examined, and aspects of social–ecological systems thinking that pose challenges for its application in this context are considered. Wider implications and limitations of social–ecological systems approaches to research and practice in (global) governance for sustainability are discussed. The general conclusion is that social–ecological systems research may offer insights into the governance of social and environmental impacts of agri-food systems and other complex systems at certain scales. However, the formal utility of concepts like resilience, vulnerability and adaptability becomes considerably less clear as research turns to analyses of larger, complex, globally teleconnected systems, where the main contribution of such concepts may lie in their metaphorical appeal to important aspects of interconnectivity and interdependence.  相似文献   
997.
Managing disaster risk is increasingly being considered a key line of response in climate adaptation. While funding support for adaptation has been pledged, rationales for support and cost implications are essentially unclear, which may explain why financing is currently only forthcoming at low levels. Various estimates for the costs of adaptation have been suggested, yet the rationale and robustness of the estimates have been difficult to verify. Focusing on weather-related extreme events, we conduct a global assessment of the public finance costs for financially managing extreme event risks. In doing so, we assess countries’ fiscal disaster vulnerability, which we operationalize as the public sector's ability to pay for relief to the affected population and support the reconstruction of lost assets and infrastructure. Methods employed include minimum-distance techniques to estimate the tail behaviour of country disaster risks as well as the inclusion of non-linear loss and financing resources relationships. We find that many countries appear fiscal vulnerable and would require assistance from the donor community in order to bolster their fiscal resilience. Our estimates may inform decisions pertaining to a global fund for absorbing different levels of country risks. We find the costs of funds covering different risk layers to be in the lower billions of dollars annually, compared to estimates of global climate adaptation which reach to more than USD 100 billion annually. Our estimates relate to today's climate, and while disaster losses have currently not been robustly linked to climate change, physical science has made a strong case in attributing changes in climate extremes to anthropogenic Climate Change. We suggest that estimates of current weather variability and related risks, although also associated with substantial uncertainty, can be interpreted as a baseline for discussion and any future projections of risks.  相似文献   
998.
In 1997, the global value of ecosystem services was estimated to average $33 trillion/yr in 1995 $US ($46 trillion/yr in 2007 $US). In this paper, we provide an updated estimate based on updated unit ecosystem service values and land use change estimates between 1997 and 2011. We also address some of the critiques of the 1997 paper. Using the same methods as in the 1997 paper but with updated data, the estimate for the total global ecosystem services in 2011 is $125 trillion/yr (assuming updated unit values and changes to biome areas) and $145 trillion/yr (assuming only unit values changed), both in 2007 $US. From this we estimated the loss of eco-services from 1997 to 2011 due to land use change at $4.3–20.2 trillion/yr, depending on which unit values are used. Global estimates expressed in monetary accounting units, such as this, are useful to highlight the magnitude of eco-services, but have no specific decision-making context. However, the underlying data and models can be applied at multiple scales to assess changes resulting from various scenarios and policies. We emphasize that valuation of eco-services (in whatever units) is not the same as commodification or privatization. Many eco-services are best considered public goods or common pool resources, so conventional markets are often not the best institutional frameworks to manage them. However, these services must be (and are being) valued, and we need new, common asset institutions to better take these values into account.  相似文献   
999.
Good governance is widely seen as a prerequisite for effective natural resources management in the context of environmental decline and increasing anthropogenic pressures. Few studies quantitatively examine governance principles, or explore links between perceptions of community members and the governance that shapes their behaviour. Comparative work, spanning multiple sites and contexts, is rare. This paper measures community members’ perceptions of governance in twelve coral reef-dependent communities across four countries in the Wider Caribbean Region. In relation to established principles of ‘good governance’, multiple correspondence analysis indicates that perceptions can be reliably described using two themes, institutional acceptance and engagement. These explain over 50% of variation in individual perceptions. These measurable themes provide an indication of the social fit of governance arrangements, and have implications for expected outcomes, including support for management and compliance with regulations. Cluster analysis provides unique empirical evidence linking structural characteristics of governance to community perceptions; four of five good governance indicators were present in communities with positive perceptions. Results suggest a combination of supportive structures and processes are necessary to achieve governance systems positively perceived by community members. Findings are relevant to those seeking to design management systems and governance structures that are appropriate to local circumstances and will engender stakeholder support.  相似文献   
1000.
International environmental policy has evolved from a focus on single issues to more integrated approaches under the framework of sustainable development. This transition has been accompanied by a growing use of targets among international organisations. Targets have long been used in industry and corporate planning, but some have questioned their relevance in the ambit of environmental and sustainable development policy. This paper addresses the question of whether international targets help advance environmental policy integration in international governance. It explores whether the international target of significantly reducing the rate of biodiversity loss by 2010, adopted by the Conference of the Parties to the Convention on Biological Diversity (CBD) in 2002, enabled co-ordination and coherence in international biodiversity governance. The effects of the Target on the cluster of biodiversity-related conventions and their implementation in countries of Latin America and the Caribbean are examined. The analysis is based on official documents and interviews with secretariat officials, international experts and national focal points conducted between September 2011 and April 2012. A claim is made that the 2010 Biodiversity Target was, in essence, a conservation goal that did not fully honour the CBD's sustainable development mission. The Target triggered increased co-operation in the biodiversity cluster without bringing greater alignment of policies and implementation activities around the CBD's sustainability principles. The study suggests that, if targets are to advance EPI among international institutions, they need to be appropriated by relevant stakeholders and supported by implementation strategies that secure their continuous commitment.  相似文献   
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