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671.
Within the scope of an investigation for the German Federal Environment Agency (“Umweltbundesamt”), the basics for the estimation of the methane emissions from the landfilling of mechanically and biologically treated waste (MBT) were developed. For this purpose, topical research including monitoring results regarding the gas balance at MBT landfills was evaluated.For waste treated to the required German standards, a methane formation potential of approximately 18–24 m3 CH4/t of total dry solids may be expected. Monitoring results from MBT landfills show that a three-phase model with differentiated half-lives describes the degradation kinetics in the best way. This is due to the fact that during the first years of disposal, the anaerobic degradation processes still proceed relatively intensively. In addition in the long term (decades), a residual gas production at a low level is still to be expected.Most of the soils used in recultivation layer systems at German landfills show a relatively high methane oxidation capacity up to 5 l CH4/(m2 h). However, measurements at MBT disposal sites indicate that the majority of the landfill gas (in particular at non-covered areas), leaves the landfill body via preferred gas emission zones (hot spots) without significant methane oxidation. Therefore, rather low methane oxidation factors are recommended for open and temporarily covered MBT landfills. Higher methane oxidation rates can be achieved when the soil/recultivation layer is adequately designed and operated.Based on the elaborated default values, the First Order Decay (FOD) model of the IPCC Guidelines for National Greenhouse Gas Inventories, 2006, was used to estimate the methane emissions from MBT landfills. Due to the calculation made by the authors emissions in the range of 60,000–135,000 t CO2-eq./a for all German MBT landfills can be expected. This wide range shows the uncertainties when the here used procedure and the limited available data are applied. It is therefore necessary to generate more data in the future in order to calculate more precise methane emission rates from MBT landfills. This is important for the overall calculation of the climate gas production in Germany which is required once a year by the German Government.  相似文献   
672.
If the threshold that triggers climate catastrophe is known with certainty, and the benefits of avoiding catastrophe are high relative to the costs, treaties can easily coordinate countries' behavior so as to avoid the threshold. Where the net benefits of avoiding catastrophe are lower, treaties typically fail to help countries cooperate to avoid catastrophe, sustaining only modest cuts in emissions. These results are unaffected by uncertainty about the impact of catastrophe. By contrast, uncertainty about the catastrophic threshold normally causes coordination to collapse. Whether the probability density function has “thin” or “fat” tails makes little difference.  相似文献   
673.
This research explores the institutional water governance system of irrigated agricultural producers in Mendoza, Argentina in the context of a changing climate (predominantly increasing events of drought and water scarcity). An assessment is made of the impact of water governance instruments on producers using the methodology of vulnerability and adaptive capacity. Analysis focuses on the impact of the institutional water governance system on the adaptive capacity of producers’ resources, or capitals (human, social, economic, technological, and natural). Conclusions and suggestions for improving the resiliency of agricultural producers and increasing the adaptive dimensions of Mendoza’s water governance system are made based on this analysis.  相似文献   
674.
The restricted definition of “climate change” used by the Framework Convention on Climate Change (FCCC) has profoundly affected the science, politics, and policy processes associated with the international response to the climate issue. Specifically, the FCCC definition has contributed to the gridlock and ineffectiveness of the global response to the challenge of climate change. This paper argues that the consequences of misdefining “climate change” create a bias against adaptation policies and set the stage for the politicization of climate science. The paper discusses options for bringing science, policy and politics in line with a more appropriate definition of climate change such as the more comprehensive perspective used by the Intergovernmental Panel on Climate Change.  相似文献   
675.
This article applies a ‘knowledge brokering’ approach to contextualise the development of an integrated computer modelling tool into the real world policy context of adaptation of agriculture to climate change at the EU level. In particular, the article tests a number of knowledge brokering strategies described and theorised in the literature, but seldom empirically tested. The article finds that while the policy context can be used to identify a theoretically informed knowledge brokering strategy, in practice a strategy's ‘success’ is more informed by practical considerations, such as whether the tool development process is knowledge or demand driven. In addition, in practice the knowledge brokering process is found to be dynamic and messy, which is not always apparent in the literature. The article goes on to question the perception that there is always a need (or a desire) to bridge the gap between researchers and policy makers in the tool development process. Rather than a problem of design and communication, the science policy interface may be characterised more by a high level of competition between researchers and research organisations to have their tool legitimised by its use in the policy making process.  相似文献   
676.
Air quality and related health effects are not only affected by policies directly addressed at air pollution but also by other environmental strategies such as climate mitigation. This study addresses how different climate policy pathways indirectly bear upon air pollution in terms of improved human health in Europe. To this end, we put in perspective mitigation costs and monetised health benefits of reducing PM2.5 (particles less than 2.5 μm in diameter) and ozone concentrations.Air quality in Europe and related health impacts were assessed using a comprehensive modelling chain, based on global and regional climate and chemistry-transport models together with a health impact assessment tool. This allows capturing both the impact of climate policy on emissions of air pollutants and the geophysical impact of climate change on air quality.Results are presented for projections at the 2050 horizon, for a set of consistent air pollution and climate policy scenarios, combined with population data from the UN's World Population Prospects, and are expressed in terms of morbidity and mortality impacts of PM2.5 and ozone pollution and their monetised damage equivalent.The analysis shows that enforcement of current European air quality policies would effectively reduce health impacts from PM2.5 in Europe even in the absence of climate policies (life years lost from the exposure to PM2.5 decrease by 78% between 2005 and 2050 in the reference scenario), while impacts for ozone depend on the ambition level of international climate policies. A move towards stringent climate policies on a global scale, in addition to limiting global warming, creates co-benefits in terms of reduced health impacts (68% decrease in life years lost from the exposure to PM2.5 and 85% decrease in premature deaths from ozone in 2050 in the mitigation scenario relative to the reference scenario) and air pollution cost savings (77%) in Europe. These co-benefits are found to offset at least 85% of the additional cost of climate policy in this region.  相似文献   
677.
As nations develop policies for low-carbon transitions, conflicts with existing policies and planning tools are leading to competing demands for land and other resources. This raises fundamental questions over how multiple demands can best be managed. Taking the UK as an empirical example, this paper critiques current policies and practices to explore the interdependencies at the water-energy-food nexus. It considers how current land uses and related policies affect the UK’s resilience to climate change, setting out an agenda for research and practice relevant to stakeholders in land-use management, policy and modelling. Despite recent progress in recognising such nexus challenges, most UK land-related policies and associated science continue to be compartmentalised by both scale and sector and seldom acknowledge nexus interconnections. On a temporal level, the absence of an over-arching strategy leaves inter-generational trade-offs poorly considered. Given the system lock-in and the lengthy policy-making process, it is essential to develop alternative ways of providing dynamic, flexible, practical and scientifically robust decision support for policy-makers. A range of ecosystem services need to be valued and integrated into a resilient land-use strategy, including the introduction of non-monetary, physical-unit constraints on the use of particular services.  相似文献   
678.
This paper contributes to an emerging body of literature on policy experimentation and governance transformation processes. We use the example of REDD+ as consisting of policy experiments in an emerging domestic policy domain to understand obstacles to transformations in forest and climate governance. We ask two interlinked questions: to what extent did the establishment of the REDD+ Agency challenge ‘business as usual’ in Indonesia’s forest and climate policy arena?; and what does this mean for a transformation away from policies and governance that enable deforestation and forest degradation? We draw on the transformation literature to better understand the role of REDD+ to achieve a transformative shift in climate governance. As an experiment of transformative climate governance, the study of REDD+ provides important insights for other forest or climate programs. Our analysis shows that the REDD+ Agency was successful in some extend in introducing an alternative governance mechanism and in shaking the governance structures but we also note that some of the key actors thought that greater ownership was achieved when the REDD+ Agency was dissolved and the mandate was returned to the ministries. We conclude that policy experimenting is a process, and while the creation of novel policies and their experimentation is important, also their assimilation may lead to new opportunities.  相似文献   
679.
Despite the considerable progress made in the last decade towards building governance systems for climate change adaptation in Africa, implementation still limits positive responses. This study applies an iterative process of field assessments and literature reviews across multiple governance levels and spatial scales to identify constraints to effective formulation and implementation of climate change related policies and strategies in Uganda. Data was collected through sex-segregated participatory vulnerability assessments with farming communities in Rakai district, policy document reviews, and interviews with policy actors at national and district levels. Findings reveal that the key challenges to effective policy implementation are diverse and cut across the policy development and implementation cycle. Policies are mainly developed by central government agencies; other actors are insufficiently involved while local communities are excluded. There is also a communication disconnect between national, district, and community levels. Coupled with limited technical capacity and finances, political interference, and absence of functional implementation structures across these levels, climate change adaptation becomes constrained. We propose strategies that enhance linkages between levels and actors, which will improve policy formulation, implementation and ultimately adaptation by smallholders.  相似文献   
680.
Motivation plays a powerful role in guiding human decision-making and behaviour, including adaptation to climate change. This study aimed to determine whether community-based governance would increase behavioural support, in the form of donation behaviour, for a climate change adaptation trust fund. A sample of 548 Australians was randomly assigned to view one of two governance scenarios: (1) a community-based scenario in which community members were afforded a high level of autonomy in designing and allocating funding within a trust fund to help their community adapt to climate change, or (2) a government-centred scenario in which decision making regarding the trust fund remained with government officials. Path analysis revealed that the community-based scenario produced significantly higher levels of perceived autonomy support within the study’s participants. High levels of perceived autonomy support predicted higher levels of autonomous motivation (indicating stronger citizenship) and lower levels of amotivation, a motivational pattern, which, in turn, predicted greater willingness to donate to the climate change adaptation trust. Results are interpreted in terms of Self-Determination Theory and Motivational Crowding Theory.  相似文献   
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