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121.
碳关税是各国高度关注的贸易问题,因涉及各国经贸利益,南北国家在碳关税问题上分歧很大。任何有关碳关税的政策措施,都会引起发展中国家的强烈反对。因此,部分发达国家试图另辟蹊径,在国际贸易中通过增加生产标准、碳标签等技术要求,以比较隐蔽的方式实现执行碳关税的目的。文中将这些隐蔽的但能起到碳关税执行效果的政策措施归纳为隐形碳关税,并定义隐形碳关税是指那些虽然没有在边境环节征收碳关税,但与征收碳关税起到相同贸易壁垒作用的,对发展中国家出口产品和服务构成限制的政策和措施。隐形碳关税比较典型的表现形式包括生产标准、碳标签等措施。这些措施本身是政策中性的,并不构成隐形碳关税,但如果叠加了转移应对气候变化成本、限制发展中国家产业发展等目的,这些措施的性质便不再中性,而成为现实中的贸易壁垒。隐形碳关税的治理应该是国际气候治理进程的一个部分,《联合国气候变化框架公约》则应是隐形碳关税治理的主要国际平台。无论是在气候公约内还是气候公约外的治理机制,隐形碳关税的国际治理都应遵循气候公约的相关原则,尤其是共同但有区别责任原则,区别对待发达和发展中国家的责任和义务,充分发挥生产标准、碳标签等措施的积极环境效用,同时约束其不当使用,建立公平、互信、务实的国际合作模式,实现气候治理与经济发展的协同。  相似文献   
122.
Abstract

The Ninth Conference of the Parties (COP-9) decided to adopt an accounting system based on expiring carbon credits to address the problem of non-permanent carbon storage in forests established under the Clean Development Mechanism (CDM). This article reviews and discusses carbon accounting methods that were under consideration before COP-9 and presents a model which calculates the minimum area that forest plantation projects should reach to be able to compensate CDM transaction costs with the revenues from carbon credits. The model compares different accounting methods under various sets of parameters on project management, transaction costs, and carbon prices. Model results show that under current carbon price and average transaction costs, projects with an area of less than 500 ha are excluded from the CDM, whatever accounting method is used. Temporary crediting appears to be the most favorable approach to account for non-permanent carbon removal in forests and also for the feasibility of smaller projects. However, lower prices for credits with finite lifetimes may prevent the establishment of CDM forestry projects. Also, plantation projects with low risk of unexpected carbon loss and sufficient capacity for insuring or buffering the risk of carbon re-emission would benefit from equivalence-adjusted average carbon storage accounting rather than from temporary crediting.  相似文献   
123.
Abstract

A series of meetings of two ‘Citizen Panels’ were held to explore public perceptions of off-shore carbon dioxide (CO2) capture and storage (CCS). In addition, a face-to-face survey of 212 randomly selected individuals was conducted. We found that, on first hearing about CCS in the absence of any information on its purpose, the majority of people either do not have an opinion at all or have a somewhat negative perspective. However, when (even limited) information is provided on the role of CO2 storage in reducing CO2 emissions to the atmosphere, opinion shifts towards expressing slight support for the concept.

Support depends, however, upon concern about human-caused climate change, plus recognition of the need for major reductions in CO2 emissions. It also depends upon CCS being seen as just one part of a wider strategy for achieving significant cuts in CO2 emissions. A portfolio including renewable energy technologies, energy efficiency, and lifestyle change to reduce demand was generally favoured. CCS can be part of such a portfolio, but wind, wave, tidal, solar and energy efficiency were preferred. It was felt that uncertainties concerning the potential risks of CCS had to be better addressed and reduced; in particular the risks of accidents and leakage (including the potential environmental, ecosystem and human health impacts which might result from leakage).  相似文献   
124.
《Climate Policy》2013,13(1):41-54
Abstract

One strategy for mitigating the increase in atmospheric carbon dioxide is to expand the size of the terrestrial carbon sink, particularly forests, essentially using trees as biological scrubbers. Within relevant ranges of carbon abatement targets, augmenting carbon sequestration by protecting and expanding biomass sinks can potentially make large contributions at costs that are comparable or lower than for emission source controls. The Kyoto protocol to the framework convention on climate change includes many provisions for forest and land use carbon sequestration projects and activities in its signatories' overall greenhouse gas mitigation plans. In particular, the protocol provides a joint implementation provision and a clean development mechanism that would allow nations to claim credit for carbon sequestration projects undertaken in cooperation with other countries. However, there are many obstacles for implementing an effective program of land use change and forestry carbon credits, especially measurement challenges. This paper explains the difficulty that even impartial analysts have in assessing the carbon offset benefits of projects. When these measurement challenges are combined with self-interest, asymmetries of information, and large numbers, it prevents to a project-based forest and land use carbon credit program may be insurmountable.  相似文献   
125.
《Climate Policy》2013,13(4):319-333
Abstract

This paper discusses the results of the BEAP linear programming model that has been developed to study the optimal use of biomass and land for greenhouse gas emission reduction, notably the competition between food production, biomass production for energy and materials and afforestation. The model results suggest up to 100 EJ biomass use in case of global policies (about 20% of global primary energy use). The biomass is used for industrial and residential heating, transportation fuels and as a feedstock for plastics. In the electricity markets competing emission reduction options are more cost-effective than biomass. In case the Kyoto protocol is continued beyond 2010 the developed countries can rely in 2020–2030 on afforestation and land use change credits from developing countries, without any major use of other emission reduction strategies. However, in case of a planning perspective of more than half a century bioenergy is preferred instead of afforestation. The results indicate a limited impact on global agricultural trade, but food demand may be affected by CO2 policies.  相似文献   
126.
《Climate Policy》2013,13(4):335-351
Abstract

Parties negotiating the Kyoto Protocol recently agreed that Clean Development Mechanism (CDM) investments can include carbon sequestration projects in developing countries. However, guidelines for achieving the socio-economic and environmental objectives of the CDM, and other concerns with sinks projects, have yet to be elaborated. Independently of the Kyoto process, international efforts have advanced to define and certify sustainably managed forests through processes, such as that of the Forest Stewardship Council (FSC). In this paper, the FSC-US principles and criteria for sustainable forest management are evaluated in light of current concerns for guiding afforestation and reforestation projects in the CDM. It is found that the FSC criteria would help to meet some of the objectives of the Kyoto Protocol, including provisions to reduce the risk of premature carbon loss, and features that could somewhat lessen leakage of emissions outside the project area. Existing FSC monitoring and verification procedures provide some, but insufficient, overlap with expected requirements for measuring carbon stock changes. FSC principles and criteria articulate stringent guidelines for meeting environmental and social goals that reflect years of negotiations between environmental, timber, human rights and labor interests.  相似文献   
127.
《Climate Policy》2013,13(2-3):179-196
Abstract

The agreement on implementation of the Kyoto Protocol achieved at COP7 in Marrakech has important implications for investment in greenhouse gas emission reduction projects in developing countries through the Clean Development Mechanism (CDM). The required actual emission reductions for participating Annex B countries overall will be relatively small, as the United States do not intend to ratify the protocol and significant amounts of carbon sequestered in domestic sinks can be credited. In addition, the potential supply of surplus emission permits (hot air) from Russia and other economies in transition may be as high as total demand in the first commitment period. Thus, even under restraint of hot air sellers, CDM demand will be limited, and a low demand, low price carbon market scenario appears likely.

The magnitude of the CDM will be influenced by a host of factors both on the demand and the supply-side. We analyse these using a quantitative model of the global carbon market, based on marginal abatement cost curves. Implementation and transaction costs, as well as baseline and additionality rules affect the CDM's share in the carbon market. Demand for the CDM is sensitive to changes in business-as-usual emissions growth in participating Annex B countries, and also to crediting for additional sinks. Permit supply from Russia and other economies in transition is possibly the most crucial factor in the carbon market.  相似文献   
128.
 An estimated average CO2 output from Etna's summit craters in the range of 13±3 Mt/a has recently been determined from the measured SO2 output and measured CO2/SO2 molar ratios. To this amount the CO2 output emitted diffusely from the soil (≈ 1 Mt/a) and the amount of CO2 dissolved in Etna's aquifers (≈ 0.25 Mt/a) must be added. Data on the solubility of CO2 in Etnean magmas at high temperature and pressure allow the volume of magma involved in the release of such an amount of this gas to be estimated. This volume of magma (≈ 0.7 km3/a) is approximately 20 times greater than the volume of magma erupted annually during the period 1971–1995. On the basis of C-isotopic data of CO2 collected in the Etna area and of new hypotheses on the source of Mediterranean magmas, significant contributions of CO2 from non-magmatic sources to the total output from Etna are unlikely. Such large outputs of CO2 and also of SO2 from Etna could be due to an anomalously shallow asthenosphere beneath the volcano that allows a continuous escape of gases toward the surface, even without migration of magma. Received: 7 August 1996 / Accepted: 9 November 1996  相似文献   
129.
Evaporation dominates the removal of water from Lake Tanganyika, and therefore the oxygen isotope composition of lake water has become very positive in comparison to the waters entering the lake. The surface water in Lake Tanganyika has remained relatively unchanged over the last 30 years with a seasonal range of +3.2 to +3.5 VSMOW. Water from small rivers entering the lake seems to have a 18O value between –3.5 and –4.0, based on scattered measurements. The two largest catchments emptying into the lake deliver water that has a 18O value between these two extremes. This large contrast is the basis of a model presented here that attempts to reconstruct the history of runoff intensity based on the 18O of carbonate shells from Lake Tanganyika cores. In order to use biogenic carbonates to monitor changes in the 18O of mixing-zone water, however, the oxygen isotope fractionation between water and shell carbonate must be well understood. The relatively invariant environmental conditions of the lake allow us to constrain the fractionation of both oxygen and carbon isotope ratios. Although molluskan aragonitic shell 18O values are in agreement with published mineral-water fractionations, ostracode calcite is 1.2 more positive than that of inorganic calcite precipitated under similar conditions. Ostracode shell 18O data from two cores from central Lake Tanganyika suggest that runoff decreased in the first half of this millennium and has increased in the last century. This conclusion is poorly constrained, however, and much more work needs to be done on stable isotope variation in both the waters and carbonates of Lake Tanganyika. We also compared the 13C of shells against predicted values based solely on the 13C of lake water dissolved inorganic carbon (DIC). The ostracode Mecynocypria opaca is the only ostracode or mollusk that falls within the predicted range. This suggests that M. opaca has potential for reconstructing the carbon isotope ratio of DIC in Lake Tanganyika, and may be a useful tool in the study of the history of the lakes productivity and carbon cycle.  相似文献   
130.
Geochemical signals of bulk sedimentary organic matter from three cores from Lake Tanganyika provided information about both internal processes and terrestrial inputs to the lake. Indications of land use change were detected in the geochemical records of the watersheds, and the timing of these changes was consistent with historical records of population demographics. While C:N ratios suggested that the distance from shore might be important in influencing the relative amount of allochthonous vs. autochthonous material, all cores were dominated by autochthonous organic matter. In general, nitrogen isotopes were more positive at disturbed sites, indicating inputs of enriched soil nitrate that was subsequently taken up by phytoplankton. In contrast, carbon isotopes did not reflect land use patterns, and a post-1950s decline in carbon isotope ratios found in all cores may indicate a lake-wide decrease in productivity. These interpretations were consistent with pollen and climate records.  相似文献   
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