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101.
United States and Canadian governments have responded to legal requirements to reduce human‐induced whale mortality via vessel strikes and entanglement in fishing gear by implementing a suite of regulatory actions. We analyzed the spatial and temporal patterns of mortality of large whales in the Northwest Atlantic (23.5°N to 48.0°N), 1970 through 2009, in the context of management changes. We used a multinomial logistic model fitted by maximum likelihood to detect trends in cause‐specific mortalities with time. We compared the number of human‐caused mortalities with U.S. federally established levels of potential biological removal (i.e., species‐specific sustainable human‐caused mortality). From 1970 through 2009, 1762 mortalities (all known) and serious injuries (likely fatal) involved 8 species of large whales. We determined cause of death for 43% of all mortalities; of those, 67% (502) resulted from human interactions. Entanglement in fishing gear was the primary cause of death across all species (n = 323), followed by natural causes (n = 248) and vessel strikes (n = 171). Established sustainable levels of mortality were consistently exceeded in 2 species by up to 650%. Probabilities of entanglement and vessel‐strike mortality increased significantly from 1990 through 2009. There was no significant change in the local intensity of all or vessel‐strike mortalities before and after 2003, the year after which numerous mitigation efforts were enacted. So far, regulatory efforts have not reduced the lethal effects of human activities to large whales on a population‐range basis, although we do not exclude the possibility of success of targeted measures for specific local habitats that were not within the resolution of our analyses. It is unclear how shortfalls in management design or compliance relate to our findings. Analyses such as the one we conducted are crucial in critically evaluating wildlife‐management decisions. The results of these analyses can provide managers with direction for modifying regulated measures and can be applied globally to mortality‐driven conservation issues. Evaluación del Manejo para Mitigar Efectos Antropogénicos sobre Ballenas Mayores  相似文献   
102.
This paper analyses CO2 emissions reduction costs based on project data from the Climate Cent Foundation (CCF), a climate policy instrument in Switzerland. Four conclusions are drawn. First, for the projects investigated, the CCF on average pays €63/ton. Due to the Kyoto Protocol, the CCF buys reductions only until 2012. This cut-off increases reported per ton reduction costs, as the additional lifetime project costs are set in relation to reductions only until 2012, rather than to reductions realised over the whole lifetime. Lifetime reduction costs are €45/t. Second, correlation between CCF's payments and lifetime reduction costs per ton is low. Projects with low per ton reduction costs should thus be identified based on lifetime per ton reduction costs. Third, the wide range of project costs per ton observed casts doubts on the widely used identification of the merit order of reduction measures based on average per ton costs for technology types. Finally, the CCF covers only a fraction of additional reduction costs. Decisions to take reduction efforts thus depend on additional, non-observable and/or non-economic motives. Any generalisation of results has to consider that this analysis is based on prospective costs of a sub-sample of projects in Switzerland.  相似文献   
103.
Broad stakeholder involvement cannot be assumed in all environmental planning and management processes that have critical land use dimensions. This paper illustrates how concepts and techniques from social network analysis (SNA) can be used to examine and better understand the roles of one type of stakeholders, planners, in environmentally oriented planning and management processes led by other professions. Two cases of natural hazard mitigation planning led by emergency managers illustrate the usefulness of three SNA concepts of network structural characteristics in understanding how differences in planner involvement may influence incorporation of land use approaches in local natural hazard mitigation plans aimed at reducing long term risks from natural hazards.  相似文献   
104.

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Goal Scope and Background. The European Directive on Energy Performance of Buildings which came into force 16 December 2002 will be implemented in the legislation of Member States by 4 January 2006. In addition to the aim of improving the overall energy efficiency of new buildings, large existing buildings will become a target for improvement, as soon as they undergo significant renovation. The building sector is responsible for about 40% of Europe's total end energy consumption and hence this Directive is an important step for the European Union in order that it should reach the level of saving required by the Kyoto Agreement. In this the EU is committed to reduce CO2 emissions relative to the base year of 1990 by 8 per cent, by 2010. But what will be the impact of the new Directive, how large could be the impacts of extending the obligation for energy efficiency retrofitting towards smaller buildings? Can improvement of the insulation offset or reduce the growing energy consumption from the increasing installation of cooling installations? EURIMA, the European Insulation Manufacturers Association and EuroACE, the European Alliance of Companies for Energy Efficiency in Buildings, asked Ecofys to address these questions.

Methods

The effect of the EPB Directive on the emissions associated with the heating energy consumption of the total EU 15 building stock has been examined in a model calculation, using the Built Environment Analysis Model (BEAM), which was developed by Ecofys to investigate energy saving measures in the building stock. The great complexity of the EU-15 building stock had to be simplified by examining five standard buildings with eight insulation standards, which are assigned to building age and renovation status. Furthermore, three climatic regions (cold, moderate, warm) were distinguished for the calculation of the heating energy demand. This gave a basic 210 building types for which the heating energy demand and CO2 emissions from heating were calculated according to the principles of the European Norm EN 832.

Results and Discussion

The model calculations demonstrates that the main contributor to the total heating related CO2 emissions of 725 Mt/a from the EU building stock in 2002 is the residential sector (77%) while the remaining 23% originates from non-residential buildings. In the residential sector, single-family houses represent the largest group responsible for 60% of the total CO2 emissions equivalent to 435 Mt/a.

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- The technical potential: If all retrofit measures in the scope of the Directive were realised immediately for the complete residential and non-residential building stock the overall CO2 emission savings would add up to 82 Mt/a. An additional saving potential compared to the Directive of 69 Mt/a would be created if the scope of the Directive was extended to cover retrofit measures in multi-family dwellings (200-1000m2) and non-residential buildings smaller than 1000m2 used floor space. In addition including the large group of single-family dwellings would lead to a potential for additional CO2 emission reductions compared to the Directive of 316 Mt/a.

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- Temporal mobilization of the potential: Calculations based on the building stock as it develops over time with average retrofit rates demonstrated that regulations introduced following the EPB Directive result in a CO2 emissions decrease of 34 Mt/a by the year 2010 compared to the business as usual scenario. Extending the scope of the EPB Directive to all residential buildings (including single and multi-family dwellings), the CO2 emission savings potential over the 'business as usual' scenario could be doubled to 69 Mt/a in the year 2010. This creates an additional saving potential compared to the Directive of 36 Mt/a.

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- Cooling demand: The analysis demonstrated that in warm climatic zones the cooling demand can be reduced drastically by a combination of lowering the internal heat loads and by improved insulation. With the reduction of the heat loads to a moderate level the cooling demand, e.g. of a terraced house located in Madrid, can be reduced by an additional 85% if the insulation level is improved appropriately.

Conclusions

This study demonstrates that the European Directive on Energy Performance of Buildings will have a significant impact on the CO2 emissions of the European building stock. The main saving potential lies in insulation of the existing building stock. Beyond this, CO2 emissions could, however, be greatly reduced if the scope of the Directive were to be extended to include retrofit of smaller buildings.

Recommendation and Perspective

The reductions should be seen in relation to the remaining gap of 190 Mt CO2 eq. per annum between the current emission levels of EU-15 and the target under the Kyoto-Protocol for the year 2010. The energy and industrial sector will probably contribute only a fraction of this reduction via the newly established EU emissions trading scheme and connected projects under the flexible mechanism. In addition, the traffic sector is likely to continue its growth path leading to a widening of the gap. Thus, there is likely to be considerable pressure on the EU building sector to contribute to the EU climate targets beyond what will be achieved by means of the current EPB Directive. Legislators on the EU and national level are therefore advised to take accelerated actions to tap the very significant emission reduction potentials available in the EU building stock.  相似文献   
105.
Numerous empirical and simulation-based studies have documented or estimated variable impacts to the economic growth of nation states due to the adoption of domestic climate change mitigation policies. However, few studies have been able to empirically link projected changes in economic growth to the provision of public goods and services. In this research, we couple projected changes in economic growth to US states brought about by the adoption of a domestic climate change mitigation policy with a longitudinal panel dataset detailing the production of outdoor recreation opportunities on lands managed in the public interest. Joining empirical data and simulation-based estimates allow us to better understand how the adoption of a domestic climate change mitigation policy would affect the provision of public goods in the future. We first employ a technical efficiency model and metrics to provide decision makers with evidence of specific areas where operational efficiencies within the nation's state park systems can be improved. We then augment the empirical analysis with simulation-based changes in gross state product (GSP) to estimate changes to the states’ ability to provide outdoor recreation opportunities from 2014 to 2020; the results reveal substantial variability across states. Finally, we explore two potential solutions (increasing GSP or increasing technical efficiency) for addressing the negative impacts on the states’ park systems operating budgets brought about by the adoption of a domestic climate change mitigation policy; the analyses suggest increasing technical efficiency would be the most viable solution if/when the US adopts a greenhouse gas reduction policy.  相似文献   
106.
Excessive loss of fine-grained sediment to rivers is widely recognised as a global environmental problem. To address this issue, policy teams and catchment managers require an estimate of the ‘gap’ requiring remediation, as represented by the excess above ‘background’ losses. Accordingly, recent work has estimated the exceedance of modern ‘background’ sediment delivery to rivers at national scale across England and Wales due to (i) current agricultural land cover, cropping and stocking, and (ii) current land use corrected for the uptake of on-farm mitigation measures. This sectoral focus recognises that, nationally, agriculture has been identified as the principal source of fine sediment loss to the aquatic environment. Two estimates of modern ‘background’ sediment loss, based on paleolimnological evidence, were used in the analysis; the target modern ‘background’ (TMBSDR) and maximum modern ‘background’ (MMBSDR) sediment delivery to rivers. For individual (n = 4485) non-coastal water bodies, the sediment ‘gap’ in excess of TMBSDR and MMBSDR, due to current land cover, cropping and stocking, was estimated to range up to 1368 kg ha−1 yr−1 (median 61 kg ha−1 yr−1) and 1321 kg ha−1 yr−1 (median 19 kg ha−1 yr−1), respectively. The respective ranges in conjunction with current land cover, cropping and stocking but corrected for the potential impact of on-farm sediment mitigation measures were up to 1315 kg ha−1 yr−1 (median 50 kg ha−1 yr−1) and 1269 kg ha−1 yr−1 (median 8 kg ha−1 yr−1). Multiplication of the estimates of excess sediment loss corrected for current measure uptake, above TMBSDR and MMBSDR, with estimated maximum unit damage costs for the detrimental impacts of sediment pollution on ecosystem goods and services, suggested respective water body ranges up to 495 £ ha−1 yr−1 and 478 £ ha−1 yr−1. Nationally, the total loss of sediment in excess of TMBSDR was estimated at 1,389,818 t yr−1 equating to maximum environmental damage costs of £523 M yr−1, due to current structural land use, compared to 1,225,440 t yr−1 equating to maximum damage costs of £462 M yr−1 due the uptake of on-farm sediment control measures. The corresponding total loss of sediment in excess of MMBSDR was estimated at 1,038,764 t yr−1 equating to maximum damage costs of £462 M yr−1, compared with 890,146 t yr−1 and £335 M yr−1 correcting excess agricultural sediment loss for current implementation of abatement measures supported by policy instruments. This work suggests that the current uptake of sediment control measures on farms across England and Wales is delivering limited benefits in terms of reducing loadings to rivers and associated environmental damage costs.  相似文献   
107.
Will African voters support climate change policies? By 2020, the United Nations’ Green Climate Fund intends to provide tens of billions of dollars per year to African nations to support climate adaptation and mitigation policies. It is widely assumed that African citizens will support implementation of these climate policies. We observe the opposite result. In this article – across two experimental studies – we find evidence that Sub-Saharan African politicians who commit to climate change policies may lose electoral support. Electorally important swing voters with weak party affiliations are least likely to support party statements about climate change. Interviews with standing elected officials from Malawi and South Africa corroborate our experimental findings. The combined results suggest voter preferences may hinder the successful implementation of climate change policy in Sub-Saharan African democracies.  相似文献   
108.
Underground coal mine explosions is perhaps the most hazardous danger in the coal mining industries. Efforts have been made to abate the coal dust explosion by applying rock dust either dry or wet. Dry dust has the best lift characteristic which efficiently quenches the flame propagation of a potential explosion. As a trade-off, undesired respirable dust particles are thereby generated imposing a severe health hazard on coal miners. Wet dusting is an alternative to dry dusting which significantly reduces the exposure to respirable dust particles. However, wet dust is subject to adverse caking issues which lead to a drastic reduction in the dispersibility of the particles. The present work summarizes the studies conducted to date regarding the surface modification of rock dust particles for the purpose of eliminating or alleviating the problems accompanying coal mine dusting applications, meanwhile improving the dispersive properties of dust particles and the ability to suppress the coal dust explosion.  相似文献   
109.
Greenhouse gas (GHG) mitigation options in the Russian forest sector include: afforestation and reforestation of unforested/degraded land area; enhanced forest productivity; incorporation of nondestructive methods of wood harvesting in the forest industry; establishment of land protective forest stands; increase in stand age of final harvest in the European part of Russia; increased fire control; increased disease and pest control; and preservation of old growth forests in the Russian Far-East, which are presently threatened. Considering the implementation of all of the options presented, the GHG mitigation potential within the forest and agroforestry sectors of Russia is approximately 0.6–0.7 Pg C/yr or one half of the industrial carbon emissions of the United States. The difference between the GHG mitigation potential and the actual level of GHGs mitigated in the Russian forest sector will depend to a great degree on external financing that may be available. One possibility for external financing is through joint implementation (JI). However, under the JI process, each project will be evaluated by considering a number of criteria including also the difference between the carbon emissions or sequestration for the baseline (or reference) and the project case, the permanence of the project, and leakage. Consequently, a project level assessment must appreciate the near-term constraints that will face practitioners who attempt to realize the GHG mitigation potential in the forest and agroforestry sectors of their countries.  相似文献   
110.
PROBLEM: Research suggests that people who engage in risk-taking behaviors often hold specific beliefs that can mitigate or reduce their perceptions of risk associated with those behaviors. METHOD: A scale was developed (Speeding Risk Belief Scale (SRBS)) to assess beliefs about speeding-related risk and predict self-reported speeding in a random-digit telephone survey of 800 South Australian drivers between the ages of 16 and 50. RESULTS: The scale was internally consistent, and path analyses showed it to be associated with self-reported speeding, both directly and indirectly through participants' estimates of speeding-related risk. DISCUSSION: Origins of risk-mitigating beliefs and the extent to which they may be causally linked with speeding are discussed, and recommendations are made for future research. IMPACT ON INDUSTRY: This research has strong implications for the conduct of countermeasure campaigns that disseminate information on speeding-related risk.  相似文献   
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