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291.
宜昌市生态保护红线于2015年1月正式颁布实施,文章结合宜昌市生态保护红线的应用情况,剖析了生态功能红线、水环境质量红线及大气环境质量红线在实践过程中存在的主要问题,同时,对生态保护红线管理机制需要解决的重点问题进行了阐述。  相似文献   
292.
The oil industry is one of the main productive activities in Mexico and has a huge infrastructure, including a wide pipeline network that crosses urban, industrial, agricultural and natural areas. The threat of crude oil spills is greatest in those regions with a high concentration of oil extraction and refining activities, as in the case of the Coatzacoalcos and Tonalá Rivers Low Basin. This study ranked the geosystems of the basin in terms of vulnerability to pipeline crude oil spills. Very high vulnerability (level I) was assigned to the water bodies (lakes and rivers) and their margins of influence, including surfaces that flood during normal hydraulic load. High vulnerability areas (level II) comprised surfaces that can flood during extraordinary hydraulic load related with extreme hydrometeorological events. The remaining three vulnerability levels were defined for areas with low or negligible flooding potential, these were ranked according to physical (slope, relief and permeability), biological (richness, singularity and integrity) and socio-economic (social marginalization index and economic activities index) conditions. These results are presented on a map for better visualization and interpretation. This study will be useful to establish preventive and effective emergency management actions in order to reduce remediation costs and adverse effects on wild species. It also can help local and national authorities, oil industry and civil protection corps to better protect ecosystems, natural resources and human activities and goods.  相似文献   
293.
探讨了大气环境监测点位的布设方法,在区域规划环境影响评价布设大气监测点位时,应综合考虑开发区的功能区划分、区内产业分布及环境敏感点分布等情况;结合规划区内外现状及规划实施后重点污染源的位置及排放高度,根据区域污染气象条件,采用Gauss模式预测最大浓度落地点,并以此作为区域大气环境监测点的布设依据.对某区域开发规划案例进行了大气环境监测点位布设研究,通过实践,该布设方法不仅可以反映区域大气环境质量现状的空间分布特征,而且可以为区域大气环境预测提供良好的数据支持,为优化区域规划提供依据;同时,对规划后的污染源最大浓度落地点的监测,可以为单个项目的环境预测提供背景值,起到简化入区建设项目环评的作用.  相似文献   
294.
We analyze the process of landfill diversion and its main determinants, by embedding the dynamics in a frame where economic, geographical and policy variables come into play. In addition to structural and economic drivers, we primarily investigate whether the Italian tax has been effective in supporting landfill diversion. Although the Italian landfill tax dates back to 1996, the oldest in the EU, its effectiveness in terms of landfill diversion has not been assessed yet. The complexity primarily derives from the decentralized regional implementation and the absence of a full coherent dataset covering all regions. We merge this new and original data on taxes to an integrated dataset which includes economic, waste and policy variables at regional level over the period 1999–2008. Panel regressions show that the effect of tax is significant, even when taking into account for its possible endogeneity. Regions that have increased such taxes have improved waste disposal performances over time. Landfill taxes are surely not the only instrument policy makers might introduce, but they seem to play a relevant role in the evolution of Italian waste disposal performances.  相似文献   
295.
从灾害史料中,可以看出河南灾害的严重性,进而论述了河南省灾害区域成灾背景,最后针对河南省灾害现状,提出了减灾对策建议。  相似文献   
296.
PM(10) concentration and chemical composition (ions and carbon compounds) at three sampling stations in Rome and in its surroundings was determined daily during a one-month field study, carried out during December 2003. PM concentration at the traffic station was considerably higher than at the urban background and semi-rural stations; elemental carbon was detected as one of the chemical components responsible for this increase. The difference in the concentration of sulphate and ammonium was negligible, as it was expected for secondary pollutants. A negative artefact in the determination of ammonium nitrate by means of heated automatic monitors was highlighted. The dilution properties of the lower atmosphere were traced by means of a natural radioactivity monitor. This parameter has been found to play an essential role in pollution buildup. A considerable increase in PM concentration was observed to coincide with periods of atmospheric stability. The main difference in PM composition between periods of high concentration and periods of "clean" air was found to be in the increase of ammonium nitrate concentration.  相似文献   
297.
Major accidents have catastrophic effects on humans and all of society. To prevent the occurrence of major accidents, it is essential to strengthen the management of major hazard installations. Generally, effective identification and reasonable evaluation of major hazard installations are the basic steps in safety management. At present, the evaluation methods for major hazard installations mainly focus on consequence analysis and probabilistic analysis without considering the vulnerability of hazard-affected bodies. Therefore, the proposed method will introduce regional disaster system theory and comprehensively analyze hazard-formative factors, the hazard-formative environment and hazard-affected bodies to achieve a more complete and effective assessment of major hazard installations. Hazard-formative factors are evaluated based on the rapid ranking method, hazard-formative environments are evaluated based on Bayesian networks, and hazard-affected bodies are evaluated based on the fuzzy comprehensive evaluation method. A tank group and a chemical industrial park are used to verify the feasibility and effectiveness of the new method.  相似文献   
298.
Setting a baseline for carbon stock changes in forest and land use sector mitigation projects is an essential step for assessing additionality of the project. There are two approaches for setting baselines namely, project-specific and regional baseline. This paper presents the methodology adopted for estimating the land available for mitigation, for developing a regional baseline, transaction cost involved and a comparison of project-specific and regional baseline. The study showed that it is possible to estimate the potential land and its suitability for afforestation and reforestation mitigation projects, using existing maps and data, in the dry zone of Karnataka, southern India. The study adopted a three-step approach for developing a regional baseline, namely: (i) identification of likely baseline options for land use, (ii) estimation of baseline rates of land-use change, and (iii) quantification of baseline carbon profile over time. The analysis showed that carbon stock estimates made for wastelands and fallow lands for project-specific as well as the regional baseline are comparable. The ratio of wasteland Carbon stocks of a project to regional baseline is 1.02, and that of fallow lands in the project to regional baseline is 0.97. The cost of conducting field studies for determination of regional baseline is about a quarter of the cost of developing a project-specific baseline on a per hectare basis. The study has shown the reliability, feasibility and cost-effectiveness of adopting regional baseline for forestry sector mitigation projects.
N. H. RavindranathEmail:
  相似文献   
299.
We downscale the results of a global tourism simulation model at a national resolution to a regional resolution. We use this to investigate the impact of climate change on the regions of Germany, Ireland and the UK. Because of climate change, tourists from all three countries would spend more holidays in the home country. In all three countries, climate change would first reduce the number of international arrivals—as Western European international tourist demand falls—but later increase numbers—as tourism demand from increasingly rich tropical countries grows. In Ireland and the UK, the regional pattern of demand shifts is similar to the international one: tourism shifts north. In Germany, the opposite pattern is observed as the continental interior warms faster than the coast: tourism shifts south.
Jacqueline M. HamiltonEmail:
  相似文献   
300.
我国区域性大气污染问题频频发生,成为当前亟待解决的重大环境问题。区域联防联控工作需要建立相应的区域空气质量监测体系和评价方法,这对已有的监测体系提出了新的要求。在区域监测体系中需要增加臭氧、细粒子等区域性污染物及其前体物的监测,同时设立区域监控点使监测网络覆盖面由城市建成区拓展到广大近郊及农村地区。采用移动式柱浓度监测和卫星遥感监测等多样化监测手段结合超级空气站来增强区域综合监测和源解析能力。在区域内搭建监测信息共享平台和实时发布机制并建立区域空气质量预警预报系统。建立区域内统一的质量管理和质量控制方案,城市监测点质控工作由所在省市管理,区域监控点质控工作由国家统一直管。采用分区分层次的区域空气质量评价方法,评价因子包括所有六项监测指标。  相似文献   
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