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101.
WILLIAM WHITESELL 《Climate Policy》2013,13(5):457-462
An upstream cap-and-trade system that rations allowances for the carbon content of fuel inputs could achieve wider coverage than existing CO2 emission programmes or most of those proposed in draft US legislation, but would risk shortages and price spikes. Allowance price volatility could be avoided with a CO2-price corridor established through auctions, similar in some respects to how central banks manage short-term interest rates with open market operations. Building on the central bank analogy, a Greenhouse Gas Board could be established with the ‘instrument independence’ to set annual CO2-price corridors in line with broadly-framed, long-term climate goals laid out in legislation. National and regional Boards of this nature might also help facilitate the international coordination of climate policies. 相似文献
102.
A carbon tax will form the central carbon pricing instrument in South Africa. The country, however, is also in the process of setting specific short-term emissions limits at a subnational level. Additional mitigation policy instruments will thus be required to meet these targets. Although it is possible to combine sector-level quantity targets with a broad-based carbon tax, this article finds that this greatly complicates mitigation policy design, increasing both the information requirements and the likelihood of unintended consequences. The trade-offs between economic efficiency (optimized by the use of a broad-based price set by a carbon tax) and environmental effectiveness (optimized by using instruments that ensure emissions reduction targets are met) are ever present. A clear understanding of subnational quantity targets and an appreciation of the characteristics of the instruments to achieve such targets (quantity-based instruments, QBIs), the framework through which the instruments are combined, and their possible interactions, are required for effective policy making. Three possible frameworks for combining instruments are identified in the article, and some specific implications of interaction between particular QBIs and a carbon tax are suggested.Policy relevanceThis article explores the interaction of a carbon tax with mitigation policy instruments to meet subnational emissions targets in the South African context (where both a carbon tax and subnational emissions targets are currently being developed). As international negotiations progress towards countries accepting binding GHG emissions restrictions, quantity-based mitigation policy approaches become more important. In countries where a broad-based emissions trading scheme (ETS) is not feasible in the short to medium term, combining a broad-based carbon tax with subnational emission targets provides an alternative mechanism for achieving the economic efficiency and emissions certainty benefits derived from an ETS. This paper considers the mechanisms through which such a combination of instruments can be achieved. Three possible frameworks for combining instruments are identified, some specific implications of interaction between particular QBIs and a carbon tax are suggested, and guidelines and concept tools are presented to assist policy-makers in designing efficient and coherent mitigation policy. 相似文献
103.
通过实施土地开发整理,从根本上改善了农村生态环境,不仅增加了农村耕地面积,促进了农业生产水平的提高和农民增产增收,更有力地促进了农村经济发展。农业生产条件的改善,使生产成本得到有效降低,规模效益普遍提高,壮大了村集体经济实力,加快了社会主义新农村建设步伐。但工作中仍存在领导重视不够、工程质量不够高、后期管护不到位等问题,今后应进一步强化领导、规范运作、跟踪管理,以保证开发整理成效。 相似文献
104.
通过实施土地开发整理,从根本上改善了农村生态环境,不仅增加了农村耕地面积,促进了农业生产水平的提高和农民增产增收,更有力地促进了农村经济发展。农业生产条件的改善,使生产成本得到有效降低,规模效益普遍提高,壮大了村集体经济实力,加快了社会主义新农村建设步伐。但工作中仍存在领导重视不够、工程质量不够高、后期管护不到位等问题,今后应进一步强化领导、规范运作、跟踪管理,以保证开发整理成效。 相似文献
105.
106.
将数据包络分析法(DEA)应用于陕西气象资源效率评估,计算全省气象行业2007—2009年运行的综合效率值、技术效率值和规模效率值,得出综合效率和规模效率有所下降,而技术效率有所提升。其中,2009年技术效率均值为3年来最高,而2007年技术效率值为3年来最低。构造基于面板数据的气象计量经济模型对各影响效率的因素进行计量分析,气象服务用户群及公众满意度指数、农业产出GDP值占区域GDP总值的比重和资金投入强度与气象部门产出的综合效率值呈正向关系,学术论文发表数量与综合效率值呈反向关系。据此提出提升资源效率有效性的对策。 相似文献
107.
AbstractCollaborative forms of governance are increasingly favored in conservation and potentially offer a range of practical and outcome-based benefits. However, tools for critically assessing whether and how collaboration enhances the attainment of conservation objectives are lagging behind the enthusiasm. We use a framework that considers effectiveness in relation to capacity of key actors and institutions to achieve outcomes and respond to emergent problems, robustness over time (i.e. adapting to changes while still achieving objectives), context-specific drivers of change, and the structure of networks and institutions to assess common approaches for evaluating effectiveness. Network analysis performs well in terms of structure, while action research and the diagnostic method offer deep insights into capacity and context. Scenario planning performs well in understanding robustness and context but performs better when combined with a diagnostic. The evaluation reveals important insights for approaching and standardizing investigations of collaborative governance regimes and their effectiveness. 相似文献
108.
Mapping the human footprint(HF) makes it possible to quantify human influence, which has had an unprecedented impact on the global ecosystem. Using five categories of human pressure data, this study mapped the HF of the Hengduan Mountain region and assessed the effectiveness of nature reserves in reducing human impacts. The results showed that the HF of the Hengduan Mountain region was generally higher in the south and lower in the north. The HF increased by 11.24% over the past 25 years, with faster growth in the southeast. The HF growth rate in nature reserves was much lower than that across the region, which indicated that nature reserves played an important role in reducing the impact of human pressure. A study of Baimaxueshan nature reserve found that establishing nature reserves could effectively reduce the impact of human activities, and no "leakage" occurred. Population growth was an important reason for the increased HF in nature reserves. The development of ecotourism in nature reserves must be based on ecological protection. Strengthening the long-term monitoring, evaluation, and management of nature reserves is a basic requirement for their long-term development. 相似文献
109.
Ken Trudel Randy C. Belore Joseph V. Mullin Alan Guarino 《Marine pollution bulletin》2010,60(9):1606-1614
This study determined the limiting oil viscosity for chemical dispersion of oil spills under simulated sea conditions in the large outdoor wave tank at the US National Oil Spill Response Test Facility in New Jersey. Dispersant effectiveness tests were completed using crude oils with viscosities ranging from 67 to 40,100 cP at test temperature. Tests produced an effectiveness-viscosity curve with three phases when oil was treated with Corexit 9500 at a dispersant-to-oil ratio of 1:20. The oil viscosity that limited chemical dispersion under simulated at-sea conditions was in the range of 18,690 cP to 33,400 cP. Visual observations and measurements of oil concentrations and droplet size distributions in the water under treated and control slicks correlated well with direct measurements of effectiveness. The dispersant effectiveness versus oil viscosity relationship under simulated at sea conditions at Ohmsett was most similar to those from similar tests made using the Institut Francais du Pétrole and Exxon Dispersant Effectiveness (EXDET) test methods. 相似文献
110.
Marine reserves are places where wildlife and habitats are protected from extractive and depositional uses of the sea. Although considered to be the pinnacle in marine conservation, many permit non-consumptive activities with little or no regulation. This paper examines the potential impacts of 16 non-consumptive activities including scuba diving, sailing, scientific research and motor boating, and how they might compromise the conservation objectives of marine reserves. Examination of 91 marine reserves from 36 countries found little agreement or consistency in what non-consumptive activities are permitted in marine reserves and how they are regulated. The two most common activities allowed without regulation were swimming (mentioned in 80% of marine reserves and allowed in 63% of these) and kayaking (mentioned in 85%, allowed in 53%). Scuba diving was mentioned in 91% and allowed without regulation in 41%. A risk score for the likely level of threat to wildlife and/or habitats that each activity could produce was then assigned based on effects reported in the literature. The risk analysis suggests that motor boating and activities which include or require it have a high potential to negatively impact wildlife and habitats if inadequately managed. Hence protection against extractive or depositional activities alone is insufficient to secure the high standard of protection usually assumed in marine reserves. For this to be achieved activities typically considered as benign must receive appropriate management, especially with increasing recreational use. 相似文献