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31.
利用液相~(31)P核磁共振分析方法和SMT分级方法,对比研究了海河流域典型人工河流子牙新河和滏阳新河、自然河流子牙河表层沉积物中磷形态.结果发现,两条河流沉积物中TC、TN、TP含量均很高,且相关性显著,污染较重且具有同源性.沉积物中总磷在568.2~9171.9mg·kg-1之间,其中以HCl-P为主,占总磷的25.5%~81.8%之间,其次为NaOH-P,所占比例为9.3%~55.5%.使用~(31)P-NMR技术在沉积物中共检测到7类磷化合物:正磷酸盐(Ortho-P)、磷酸单酯(Mono-P)、磷脂(Lipid-P)、DNA磷(DNA-P)、焦磷酸盐(Pyro-P)、膦酸盐(Phon-P)及多聚磷酸盐(Poly-P).Ortho-P和Mono-P分别为总磷和有机磷的主要组成成分,含量分别在113.8~6226.1 mg·kg~(-1_和27.0~1991.9 mg·kg~(-1)之间.子牙河、子牙新河和滏阳新河两条河流在沉积物磷组成方面存在很大的差异子牙新河和滏阳新河沉积物中总磷明显高于子牙河.  相似文献   
32.
The East-West Center convened the international conference on climate policy in Honolulu, Hawaii, on September 4–6, 2003. Sponsored by the Dutch Ministry of Housing, Spatial Planning and the Environment, the Japanese Ministry of the Environment, Industrial Technology Research Institute (Taiwan), and Institute for Global Environmental Strategies (Japan), this major event covered almost every important issue and featured perspectives from the most important parties and stakeholders in formulating and implementing climate policies and taking international climate negotiations further. It brought together a remarkable cross-section of world opinion on climate policy after Kyoto. This report provides a summary of each presentation and highlights discussions organized under the following six session headings: Session 1: Climate Change in Focus – From Science to Policy; Session 2: U.S. Climate Policy and Perspectives; Session 3: European Union Climate Policy and Perspectives; Session 4: Challenges for other Major Industrialized Countries; Session 5: Issues Related to Developing Countries; and Session 6: Panel Discussions: Where Do We Go from Here?.  相似文献   
33.
OBJECTIVES: This work assesses the contribution to climate change resulting from emissions of the group of halogenated greenhouse gases. METHODS: A bottom-up emission model covering 22 technological sectors in four major regions is described. Emission estimates for 1996 and projection for 2010 and 2020 are presented. The costs for deep cuts into projected emission levels are calculated. RESULTS: The substances covered by this study have contributed emissions of 1100 +/- 800 MT CO2 equivalents per year in 1996. In terms of their relative contribution to emissions of CO2 equivalents, this corresponds to 3 +/- 2% of global emissions of all anthropogenic greenhouse gases. The wide range of uncertainty is due to the poorly quantified net global warming potential of the ozone depleting substances, which have an indirect cooling effect on climate through the destruction of stratospheric ozone. For annual emissions of HFCs, PFCs and SF6 (which are regulated under the Kyoto Protocol and for which global warming potentials are well defined), the relative contribution is projected to increase to 2% (600 MT CO2 eq.) of global greenhouse gas emissions by 2010. This trend is expected to continue, emissions are projected to grow to a contribution of roughly 3% (870 MT CO2 eq.) in 2020 compared to 0.9% (300 MT CO2 eq.) in 1996. For HFCs, PFCs and SF6, this study identifies global emission reduction potentials of 260 MT CO2 eq. per year in 2010 and 640 MT CO2 eq. per year in 2020 at below US$ 50 per ton. These values correspond to roughly 40% and 75% of projected emissions in 2010 and 2020, respectively.  相似文献   
34.
Global warming mitigation calculationsrequire consistent procedures for handlingtime in order to compare `permanent' gainsfrom energy-sector mitigation options with`impermanent' gains from many forest-sectoroptions. A critical part of carbonaccounting methodologies such as thosebased on `ton-years' (the product of thenumber of tons of carbon times the numberof years that each ton is held out of theatmosphere) is definition of a timehorizon, or the time period over whichcarbon impacts and benefits are considered. Here a case is made for using a timehorizon of 100 years. This choice avoidsdistortions created by much longer timehorizons that would lead to decisionsinconsistent with societal behavior inother spheres; it also avoids a rapidincrease in the implied value of time ifhorizons shorter than 100 years are used.Selection of a time horizon affectsdecisions on financial mechanisms andcarbon credit. Simple adaptations canallow a time horizon to be specified andused to calculate mitigation benefits andat the same time reserve a given percentageof weight in decision making forgenerations beyond the end of the timehorizon. The choice of a time horizon willheavily influence whether mitigationoptions such as avoided deforestation areconsidered viable.  相似文献   
35.
Should forest-based climate mitigationmeasures be approved for crediting through the CleanDevelopment Mechanism (CDM), they could offer anopportunity to accomplish three important objectives:cost-effective reductions in carbon emissions andsequestration of atmospheric carbon; conservation andrestoration of forests and their biological diversity;and, the assistance of host countries and communitiesin their socioeconomic development. However,prospective investors in CDM projects, host countriesand other CDM `stakeholders' might be expected toplace widely different priorities on achieving theseobjectives. This paper describes several factors thatwill affect investor interest in CDM projects, thecharacteristics of forest-based CDM projects that willattract investments, and an approach to identifyingprojects that meet the key objectives of multiplestakeholders. This approach entails identifyingsites, such as degraded watersheds, where CDMfinancing for forest conservation and restoration cangenerate readily monetizable local and regionalsocioeconomic benefits, while mitigating carbonemissions in forests with importance for conservingbiodiversity.  相似文献   
36.
Over the last decade, adaptive co‐management has been recommended as a policy framework to address complex and uncertain resources management issues. Implementing this theoretical management concept requires the integration of multidisciplinary research and local knowledge. Yet practical protocols to link science, policymaking and societies have yet to be developed. We designed a protocol to produce legitimate, credible and relevant solutions to a regional resources management issue. This is a two‐component protocol. A stakeholder grid categorizes stakeholder representatives in three distinct specialized dialogue arenas: institution representatives, technical experts and local end‐users. An iterative co‐design process then builds on these arenas to assess the institutional legitimacy, technical credibility and empirical relevance dimensions of a common solution initiated by an initial plausible promise. We tested this framework in Réunion to address organic waste management issues at the regional level. The plausible solution explored was the introduction of a recycling industry involved in collecting organic waste and producing and selling organic fertilizers tailored for local crop systems. The protocol application outcomes were consolidated and documented scenarios accepted by all, with knowledge exchange and the broad spread of a stabilized expectation contributing to private initiatives and public policy change.  相似文献   
37.
2016 marked the 25th anniversary of the Protocol on Environmental Protection to the Antarctic Treaty. Terrestrial ice-free areas constitute approximately 0.18% of Antarctica, but represent the most biologically active, historically rich, and environmentally sensitive sites. Antarctic soils are easily disturbed and environmental legacies of human activities are scattered across the continent; many are remnants of the 1950s-1980s when environmental protection was less comprehensive than today. Adoption of the Environmental Protocol in 1991 represented an important and proactive shift in Antarctic governance, securing environmental protection as a fundamental tenet of the Treaty System. Twenty five years on standards of environmental management have greatly improved, yet environmental pressures are compounding. Shortcomings in the implementation of the Environmental Protocol exist due to disparities in cultural values, operational realities, and inconsistent environmental impact assessments among governments and National Antarctic Programs. Non-native species management remains underdeveloped; and there is inadequate representation of all biogeographic regions within the Protected Area system; therefore jeopardizing conservation of Antarctic biodiversity and the integrity of the soil environment. Fundamental improvements are required to address the current shortcomings and ensure effective environmental protection for the next 25 years, including: (1) increased multinational and multidisciplinary collaboration to answer targeted research questions addressing contemporary management challenges, (2) effective communication of science to policy makers and environmental managers to inform decision- making, and (3) making the mandate of long-term monitoring of the terrestrial environment a high priority for all governments signatory to the Antarctic Treaty.  相似文献   
38.
Hydrofluorocarbons (HFCs) are synthetically produced compounds primarily used for cooling purposes and with strong global warming properties. In this paper, we analyze the global abatement costs for achieving the substantial reductions in HFC consumption agreed in the Kigali Amendment (KA) of the Montreal Protocol from October 2016. We estimate that compliance with the KA is expected to remove 39 Pg CO2eq or 61% of global baseline HFC emissions over the entire period 2018–2050. The marginal cost of meeting the KA targets is expected to remain below 60 €/t CO2eq throughout the period in all world regions except for developed regions where legislation to control HFC emissions has already been in place since a few years. For the latter regions, the required HFC consumption reduction is expected to come at a marginal cost increasing steadily to between 90 and 118 €/t CO2eq in 2050. Depending on the expected rate of technological development and the extent to which envisaged electricity savings can be realized, compliance with KA is estimated attainable at a global cost ranging from a net cost-saving of 240 billion € to a net cost of 350 billion € over the entire period 2018 to 2050 and with future global electricity-savings estimated at between 0.2% and 0.7% of expected future electricity consumption.  相似文献   
39.
国际碳减排活动中的利益博弈和中国策略的思考   总被引:7,自引:0,他引:7  
博弈论能够解释许多经济活动和国际关系中出现的现象和问题。利用博弈论的相关理论。对《京都议定书》各利益集团之间的利益争斗进行了分析。指出各利益集团之间斗争的内在原因。并对中国在新一轮谈判中的策略提出了一些建议:由于《京都议定书》生效,而美国仍拒绝批准《京都议定书》。并同时抛出自己的减排方案。这必然会引起新一轮的减排博弈。面对美国等一些国家施加的压力,中国在这场新的博弈中要有所准备。提出具有建设性的建议和意见。既要维护中国和大多数发展中国家的利益。又要有助于减排。  相似文献   
40.
Estimates of emissions indicate that if tropical grassland is rehabilitated by oil palm plantations, carbon fixation in plantation biomass and soil organic matter not only neutralises emissions caused by grassland conversion, but also results in the net removal of about 135 Mg carbon dioxide per hectare from the atmosphere. In contrast, the emission from forest conversion clearly exceeds the potential carbon fixation of oil palm plantings. Forest conversion on mineral soils to promote continued oil palm mono cropping causes a net release of approximately 650 Mg carbon dioxide equivalents per hectare, while the emission from peat forest conversion is even higher due to the decomposition of drained peat and the resulting emission of carbon oxide and nitrous oxide. The conversion of one hectare of forest on peat releases over 1,300 Mg carbon dioxide equivalents during the first 25-year cycle of oil palm growth. Depending on the peat depth, continuous decomposition augments the emission with each additional cycle at a magnitude of 800 Mg carbon dioxide equivalents per hectare. The creation of ‘flexibility mechanisms’ such as the clean development mechanism and emission trading in the Kyoto Protocol could incorporate plantations as carbon sinks in the effort to meet emission targets. Thus, for the oil palm industry, grassland rehabilitation is an option to preserve natural forest, avoid emissions and, if the sequestered carbon becomes tradable, an opportunity to generate additional revenue. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
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