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Insurance programmes have been indicated as a tool to reduce the economic risk associated with climate change, and crop growth simulation models can be used effectively to assess future trends in crop insurance payouts. This paper assesses the economic role of increasing weather extremes under future climate change on the expected insurance payouts for durum wheat (Triticum turgidum L. spp. durum) over the Mediterranean basin, focusing attention on the effects of heat stresses (HSs). A crop growth simulation, Sirius Quality version 2 (SQ2), calibrated for three varieties (long, medium and short growth cycle) was applied on seven sites under present (1975–1990) and future climate conditions (2030–2050) obtained from five regional circulation models under SRES scenario A1b. The intensity of HSs at anthesis was included as reducing factor of yield originally simulated by SQ2 calculated according to a specific empirical model. Simulated yields were then fitted to the most appropriate distribution, which was used to calculate the expected payouts according to the probability of yields being below a guaranteed level. We found that the simulated crop yields were, in general, negatively skewed and that Weibull probability density function (PDF), admitting negative skewing, provided the best performances in their fitting. The simulation of HSs modified the original shape of the Weibull PDF by increasing the skewness of the distribution. The results of the insurance model indicated that the modification of crop PDFs induced by HSs led to a general increase in payouts with respect to unstressed conditions, with a marked difference between present (+11 %, on average for the selected sites) and future periods (+25 %). When compared to the present, a general decrease in payouts (?1.1 %) was observed when HSs were not included in the simulations. Conversely, HSs impact resulted in a general increase in payouts (+10.3 %) where the highest increase was detected for the long growth cycle variety (+16.6 %) and the lowest for that with short growth cycle (?1.6 %). These results emphasize the importance of the appropriate characterization of crop yield distribution, the economic implications of HSs in a risk management context and a possible strategy to cope with climate change and variability.  相似文献   
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This paper presents the contribution to population exposure (PE) of regional background fine primary (PPM2.5) and secondary inorganic (SIA) particulate matter and its impact on mortality in Europe during 1997–2003 calculated with a chemistry transport model. Contributions to concentrations and PE due to emissions from shipping, Western (WEU), Eastern (EEU), and Northern Europe are compared.WEU contributes about 40% to both PPM2.5 and SIA concentrations, whereas the EEU contribution to PPM2.5 is much higher (43% of total PPM2.5) than to SIA (29% of total SIA). The population weighted average concentration (PWC) of PPM2.5 is a factor of 2.3 higher than average (non-weighted) concentrations, whereas for SIA the PWC is only a factor 1.6 higher. This is due to PPM2.5 concentrations having larger gradients and being relatively high over densely populated areas, whereas SIA is formed outside populated areas. WEU emissions contribute relatively more than EEU to PWC and mortality due to both PPM2.5 and SIA in Europe.The number of premature deaths in Europe is estimated to 301 000 per year due to PPM2.5 exposure and 245 000 due to SIA, despite 3.3 times higher average SIA concentrations. This is due to population weighting and assumed (and uncertain) higher relative risk of mortality for PPM2.5 components (2.8 times higher RR for PPM2.5). This study indicates that it might be more efficient, for the health of the European population, to decrease primary PM emissions (especially in WEU) than to decrease precursors of SIA, but more knowledge on the toxicity of different PM constituents is needed before firm conclusions can be drawn.  相似文献   
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Emergency management faces a changed reality in terms of possibilities and threats with use of new technology. Due to the ongoing changes in the operation of oil and gas production, different constellations of actors in a distributed system are built. This introduces opportunities for planning and operation. At the same time as new technology offers opportunities, the technology-enabled distributed network of actors generate challenges for emergency handling. The purpose of the study presented has been to look for possibilities for making emergency management more resilient by becoming a part of continuous risk and hazard management. The suggested three main elements that are important to consider in the development of future emergency management are (1) proactive emergency management through early risk anticipation; and emergency management’s adaptation to new and future work practices such as (2) distributed actors and (3) new technology. Based on these results we suggest broadening the scope of emergency management to systematically include monitoring, anticipation, responding and learning.  相似文献   
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Conflicting perspectives on forests has for a long time challenged forest policy development in Sweden. Disagreements about forest futures create intractable deadlocks when stakeholders talk past each other. The purpose of this study is to move beyond this situation through the application of participatory backcasting. By comparing visions of the future forest among stakeholder groups, we highlight contemporary trajectories and identify changes that were conceived as desirable. We worked with four groups: the Biomass and Bioenergy group, the Conservation group, the Sami Livelihood group and the Recreation and Rural Development group; in total representatives from 40 organizations participated in workshops articulating the groups’ visions. Our results show well-known tensions such as intrinsic versus instrumental values but also new ones concerning forests’ social values. Identified synergies include prioritization of rural development, new valued-added forest products and diversified forest management. The results may feed directly into forest policy processes facilitating the process and break current deadlocks.  相似文献   
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Ambio - The coastal zone of the Baltic Sea is diverse with strong regional differences in the physico-chemical setting. This diversity is also reflected in the importance of different...  相似文献   
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This paper applies several well-known decision criteria to the climate change problem. The policy process is represented by a simple game against nature with two possible choices: abate or no action. The outcome is considered a compound lottery, with one representing emissions and another representing damages. Assuming that costs exceed benefits of abatement for the participant, the paper analyzes how different decision criteria affect the decision to abate. The role of expert opinion and quality of information in climate change decisions are also considered. The complexity of global warming makes it impossible to completely overlook the consequences of alternative choices. The paper discusses the question of whether the use of less information demanding alternatives to expected utility theory is indicated. It concludes that the choice of criterion is a political question, and that those in favor of abatement policies might be using one of the alternatives as basis for their advice, and suggests that if the possibility of making irreversible mistakes is of great concern, then the minimax regret criterion might have increased relevance.  相似文献   
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