首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   725篇
  免费   52篇
  国内免费   11篇
安全科学   156篇
废物处理   13篇
环保管理   133篇
综合类   304篇
基础理论   57篇
污染及防治   7篇
评价与监测   33篇
社会与环境   55篇
灾害及防治   30篇
  2023年   5篇
  2022年   6篇
  2021年   11篇
  2020年   30篇
  2019年   23篇
  2018年   8篇
  2017年   20篇
  2016年   23篇
  2015年   30篇
  2014年   25篇
  2013年   27篇
  2012年   42篇
  2011年   55篇
  2010年   63篇
  2009年   52篇
  2008年   42篇
  2007年   62篇
  2006年   46篇
  2005年   37篇
  2004年   32篇
  2003年   30篇
  2002年   21篇
  2001年   21篇
  2000年   22篇
  1999年   10篇
  1998年   7篇
  1997年   3篇
  1996年   6篇
  1995年   5篇
  1994年   3篇
  1993年   2篇
  1992年   3篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1984年   1篇
  1983年   1篇
  1981年   1篇
  1980年   1篇
  1978年   1篇
  1977年   1篇
  1975年   2篇
  1974年   3篇
排序方式: 共有788条查询结果,搜索用时 15 毫秒
1.
Amphibians are severely affected by climate change, particularly in regions where droughts prevail and water availability is scarce. The extirpation of amphibians triggers cascading effects that disrupt the trophic structure of food webs and ecosystems. Dedicated assessments of the spatial adaptive potential of amphibian species under climate change are, therefore, essential to provide guidelines for their effective conservation. I used predictions about the location of suitable climates for 27 amphibian species in the Iberian Peninsula from a baseline period to 2080 to typify shifting species’ ranges. The time at which these range types are expected to be functionally important for the adaptation of a species was used to identify full or partial refugia; areas most likely to be the home of populations moving into new climatically suitable grounds; areas most likely to receive populations after climate adaptive dispersal; and climatically unsuitable areas near suitable areas. I implemented an area prioritization protocol for each species to obtain a cohesive set of areas that would provide maximum adaptability and where management interventions should be prioritized. A connectivity assessment pinpointed where facilitative strategies would be most effective. Each of the 27 species had distinct spatial requirements but, common to all species, a bottleneck effect was predicted by 2050 because source areas for subsequent dispersal were small in extent. Three species emerged as difficult to maintain up to 2080. The Iberian northwest was predicted to capture adaptive range for most species. My study offers analytical guidelines for managers and decision makers to undertake systematic assessments on where and when to intervene to maximize the persistence of amphibian species and the functionality of the ecosystems that depend on them.  相似文献   
2.
This article investigates the potential impact of sustainable energy action plans (SEAPs) on local development through a two-step methodology involving participatory planning and quantitative analysis. The first phase relies on a participatory system mapping (PSM) approach and generates a causal structure at the basis of the urban model. In the second phase, we transform the qualitative map into a system dynamic model which evaluates the effect of the SEAP on social, economic and environmental indicators. This methodology was applied to the case of Cascina Municipality (Italy). Through scenario analysis, we show that some indirect feedback can harm the achievement of the 20% emission reduction target. This process allows the local authority and stakeholders to evaluate the impact of emission reduction policies on CO2 emissions and local development, thereby generating collective learning on the systemic implications of the plan. We show that this method can enhance the ambition of emission mitigation efforts by small towns.  相似文献   
3.
近年来,天然气消费量迅速增长,天然气领域的投入和天然气储量、产量和贸易量也呈迅速增长态势,并显示出增长的巨大潜力。天然气市场需求量的大幅度增加与国内天然气供给不足造成的供需不平衡,给天然气供气业务带来了极大的挑战。本文根据近两年来天然气供应面临的危机,分别对天然气供气产业链的上、中、下游的突发事件风险进行分析;并针对供气业务中断带来的风险,从突发事件分级、应急处置流程等两个关键要素着手对应急预案进行优化。该研究对完善天然气供气突发事件应急预案、有效快速应对突发事件提供了参考和指导。  相似文献   
4.
为了进一步优化我国现有应急预案体系,从应急管理实践中分析梳理出4方面问题,包括:“在指导理念上依然没有充分体现应急准备的理念”“应急预案体系在微观、中观和宏观层面依然存在结构性问题”“应急预案的内容存在‘概念性’内容较多的情况,导致操作性和针对性不强”“预案动态管理滞后,持续改进机制尚未形成”;针对现存问题,提出基于情景构建的优化策略和方法,认为“情景构建”不但可以指导编制者分析应急需求、明确应急目标、规划应急程序,有效支撑应急预案的编制,而且可以派生出“基于情景链条的预案衔接策略”“基于任务协同的预案衔接策略”“基于资源约束的预案衔接策略”,进而从微观层面上推进预案体系的优化。研究结果可以作为各级政府和企业应急预案体系构建的参考和借鉴。  相似文献   
5.
• Impact of urban development on water system is assessed with carrying capacity. • Impacts on both water resource quantity and environmental quality are involved. • Multi-objective optimization revealing system trade-off facilitate the regulation. • Efficiency, scale and structure of urban development are regulated in two stages. • A roadmap approaching more sustainable development is provided for the case city. Environmental impact assessments and subsequent regulation measures of urban development plans are critical to human progress toward sustainability, since these plans set the scale and structure targets of future socioeconomic development. A three-step methodology for assessing and optimizing an urban development plan focusing on its impacts on the water system was developed. The methodology first predicted the pressure on the water system caused by implementation of the plan under distinct scenarios, then compared the pressure with the carrying capacity threshold to verify the system status; finally, a multi-objective optimization method was used to propose regulation solutions. The methodology enabled evaluation of the water system carrying state, taking socioeconomic development uncertainties into account, and multiple sets of improvement measures under different decisionmaker preferences were generated. The methodology was applied in the case of Zhoushan city in South-east China. The assessment results showed that overloading problems occurred in 11 out of the 13 zones in Zhoushan, with the potential pressure varying from 1.1 to 18.3 times the carrying capacity. As a basic regulation measure, an environmental efficiency upgrade could relieve the overloading in 4 zones and reduce 9%‒63% of the pressure. The optimization of industrial development showed that the pressure could be controlled under the carrying capacity threshold if the planned scale was reduced by 24% and the industrial structure was transformed. Various regulation schemes including a more suitable scale and structure with necessary efficiency standards are provided for decisionmakers that can help the case city approach a more sustainable development pattern.  相似文献   
6.
应急预案制定后的实施对于事故发生后预案的顺利运行至关重要,因此,有必要对应急预案实施过程的风险水平进行度量。以应急预案实施过程作为研究对象,基于风险理论与AHP-联系熵耦合方法开展风险评估。以应急预案实施过程风险水平为目标层,应急预案的宣传教育和培训、应急资源的定期检查落实、应急演习训练、应急预案的实用性检验、应急预案电子化、事故回顾等过程要素作为策略层,实施方法科学高效、调动工作者积极的态度、领导的重视和能力、设备的完整性作为方案层,形成应急预案实施过程风险评估三级模型;运用联系熵表征风险标准与应急预案实施过程风险水平这2个集对之间的关联性,在AHP结构模型和权重分配的基础上计算加权熵并得到目标层的总联系熵,对比标准熵区间得到应急预案实施过程的整体风险等级。结果表明,采用AHP-联系熵度量方法提高了评价结果的结构性和准确性,比传统直接加权的方法更符合实际情况。  相似文献   
7.
杨静 《环境与发展》2020,(1):238-239
在第二次全国污染源普查的基础上,利用污染源普查期间配置的软硬件,开发市级区域环境污染源管理平台,进行污染源数据的年度更新,拓展污染源普查软件应用,实现环境管理及环境执法移动终端的应用。拓展二污普一张图的功能,利用移动客户端机动实时及地定位导航等为环境管理执法和环境突发事件应急处置提供技术支持。  相似文献   
8.
高艳荣 《环境与发展》2020,(2):232-232,234
环境检测人员培训在整个生态文明建设中发挥着至关重要的作用,本文从培训计划、培训内容、培训方式、有效评价和记录归档五个方面探讨了环境检测机构人员培训工作流程,以确保机构行之有效地开展人员培训。  相似文献   
9.
张以飞 《环境与发展》2020,(4):48-49,51
针对工业废盐成分复杂、精制难度高的现状,本文提出了一种工业废盐的资源化工程方案,技术经济分析表明,该工程化方案在技术上、经济上能够实现满足投资、运营要求,具备较好的推广前景。  相似文献   
10.
通过对清查数据的结果分析,确定第二次全国污染源入户普查的对象,基于企业填报、现场入户、资料收集审核、数据核查等具体工作的实施与开展,思考和归总普查工作中影响数据质量的现实问题和难点,初步构建污染源普查质量保证体系,以期为全国污染源普查数据质量保证提供有益参考。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号