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191.
In this paper we examine the effect of Gross Domestic Product (GDP) on the level of fish intake in China in comparison with the rest of the world. We also analyse the origin and destination of China’s seafood products in order to understand the main patterns during the last decades. The results show that in the 1961–2011 period the rate of growth of the GDP in China doubled that of other developing regions, while the daily fish intake of China increased fourfold, making China the largest fish consumer in the world. Given the size and scale of China’s role in production, consumption, and global transformation of seafood markets, China is shaping a new era of industrialization in the history of the fishing industry.  相似文献   
192.
Individual household and travel behaviors represent a sizeable contribution to U.S. greenhouse gas emissions. This paper investigates people's knowledge of these behaviors and perceptions of these behaviors' impact in causing and mitigating climate change. In the present study, a sample of college students were asked to list the behaviors they perform that cause global warming (GW) and the behaviors they could perform to mitigate GW, to rate the impact of the behaviors in terms of their effect on causing or mitigating GW, and to rate their intention to perform each of the behaviors. Results revealed that this sample was well aware of the effect of driving on GW. However, participants underestimated the relative impact of adjusting the thermostat and eating meat on GW and overestimated the impact of littering on causing GW. Although knowledge about GW-mitigating behaviors was not consistently related to behavioral intention, belief that a behavior mitigated GW (whether accurate or not) was strongly related to intention to perform that behavior. Specifically, correlations between belief in the mitigating potential of a behavior and intention were relatively high for adjusting the thermostat, reducing meat consumption, and several behaviors that do not mitigate GW, but were relatively low for reducing driving and not littering. Practical implications and comparisons with previous literature are discussed.  相似文献   
193.
To investigate the interactive effects of increasing [CO2] and heat wave occurrence on isoprene (IE) and methanol (ME) emissions, Platanus orientalis was grown for one month in ambient (380 μmol mol−1) or elevated (800 μmol mol−1) [CO2] and exposed to high temperature (HT) (38 °C/4 h). In pre-existing leaves, IE emissions were always higher but ME emissions lower as compared to newly-emerged leaves. They were both stimulated by HT. Elevated [CO2] significantly reduced IE in both leaf types, whereas it increased ME in newly-emerged leaves only. In newly-emerged leaves, elevated [CO2] decreased photosynthesis and altered the chloroplast ultrastructure and membrane integrity. These harmful effects were amplified by HT. HT did not cause any unfavorable effects in pre-existing leaves, which were characterized by inherently higher IE rates. We conclude that: (1) these results further prove the isoprene's putative thermo-protective role of membranes; (2) HT may likely outweigh the inhibitory effects of elevated [CO2] on IE in the future.  相似文献   
194.
Inventing the future: scenarios, imagination, mastery and control   总被引:1,自引:1,他引:0  
The complexity of mixed social, behavioral, and natural systems—such as those encountered while analyzing, understanding, and trying to manage aspects of climate change and sustainability, requires more common theoretical frameworks and technical tools than either can bear. How does human activity relate to greenhouse gas emissions, changes in the atmosphere, climate variability, and multiple impacts, outcomes, and effects? Some of the connections can be observed and measured, many cannot. Uncertainties of every conceivable sort can occur. As the time frame into the future extends, uncertainties essentially dominate conventional theories, tools, experiences, habits, processes, and so forth. The scientific consensus linking human activity to climate change is now all but settled according to The Fourth Assessment Report of the Intergovernmental Panel on Climate Change. The consensus says little, however, about who should be doing what and for what reasons under this singular, even unique circumstance. There are no data about the future on which to rely. We are challenged to imagine many different and possible “futures” as humankind seeks to exert its mastery and control. This essay considers and then weaves together several basic issues, ideas, and topics: complexity, the concept of human intentionality, several means used to exert control in organizations and social systems, and different methods being used to imagine, invent, and communicate the future.  相似文献   
195.
Atmospheric inversions have proven to be useful tools, showing for example the likely existence of a large terrestrial carbon sink in the northern mid-latitudes. However, as we go to smaller spatial scales the uncertainties in the inversions increase rapidly, and the task of finding the distribution of the sink between North America, Europe and Asia has been shown to be very difficult. The uncertainty in the fluxes due to network selection, transport model error and inversion set up tends to be too high for studying either net annual fluxes or interannual variability on spatial scales such as the North American Boreal or Eurasian Boreal regions. We discuss the path forward; to couple together the atmospheric inversions with process based terrestrial carbon models, creating carbon data assimilation systems. Such systems are being developed now and could prove to be very powerful. The multi-disciplinary nature of the data assimilation system requires information from flux towers, soil and above ground biomass inventories, remote sensed fields, atmospheric CO2 concentrations and climate data as well as model development and will need a massive community effort if it will succeed.  相似文献   
196.
Over the next century, society will increasingly be confronted with the impacts of global change (e.g. pollution, land use changes, and climate change). Multiple scenarios provide us with a range of possible changes in socio-economic trends, land uses and climate (i.e. exposure) and allow us to assess the response of ecosystems and changes in the services they provide (i.e. potential impacts). Since vulnerability to global change is less when society is able to adapt, it is important to provide decision makers with tools that will allow them to assess and compare the vulnerability of different sectors and regions to global change, taking into account exposure and sensitivity, as well as adaptive capacity. This paper presents a method that allows quantitative spatial analyses of the vulnerability of the human-environment system on a European scale. It is a first step towards providing stakeholders and policy makers with a spatially explicit portfolio of comparable projections of ecosystem services, providing a basis for discussion on the sustainable management of Europe’s natural resources.
Marc J. MetzgerEmail: Phone: +31-317-482983Fax: +31-317-484839
  相似文献   
197.
The occasion for this forum was sparked by a front-page story in the New York Times by John M. Broder entitled, “Seeking to Save the Planet, with a Thesaurus” (May 1, 2009, p. A11). The article focused on the non-profit EcoAmerica's report, “Climate and Energy Truths: Our Common Future,” which shares research on communication approaches to engaging climate change and energy issues. The Broder article included commentary from Robert J. Brulle, Professor of Sociology and Environmental Science at Drexel University. In response, George P. Lakoff, Professor of Cognitive Science and Linguistics at UC-Berkeley, published an essay in The Huffington Post, “Why Environmental Understanding, or ‘Framing,’ Matters: An Evaluation of the EcoAmerica Summary Report” (May 19, 2009). The discussion about this report and differing approaches to environmental communication continued on blogs, in emails, and through various other forums. The editorial leadership team of this journal thought such prominent attention to environmental communication in the nexus of so many disciplines and professional investments was exciting. We are pleased the following scholars and practitioners are willing to elaborate on the stakes of this discussion in this forum.  相似文献   
198.
基于全球定位系统(GPS)的电动车辆实时监控系统设计   总被引:1,自引:0,他引:1  
电动汽车以其良好的环保效应和灵活多样的能源利用形式,已成为国际社会普遍公认的汽车工业的重要发展方向之一,作为凸显可持续发展理念和国家科技产业实力的窗口,电动汽车的规模化应用将成为彰显2008北京“绿色奥运、科技奥运”主题的鲜明标志。为确保电动汽车奥运应用的安全性与可靠性,笔者提出了基于GPS的电动车辆实时监控系统的总体设计。该系统由车载信息采集终端(OBICT)、车辆运行监控(VOP)和无线通讯网络(WCN)3个子系统构成,并能对电动汽车运行中的电池及关键部件工作状态、车辆位置等数据进行实时采集与传输。在给出系统总体结构设计的基础上,对该车载信息采集终端、车辆运行监控子系统的数据流程进行分析,并提出了相应的软/硬件架构技术、设计方法以及实现的功能。  相似文献   
199.
PROBLEM: An average of three workers a year are killed in surface mining operations when a piece of haulage equipment collides with another smaller vehicle or a worker on foot. Another three workers are killed each year when haulage equipment backs over the edge of a dump point or stockpile. Devices to monitor the blind areas of mining equipment are needed to provide a warning to operators when a vehicle, person, or change in terrain is near the equipment. METHOD: A proximity warning system (PWS) based on the global positioning system (GPS) and peer-to-peer communication has been developed to prevent collisions between mining equipment, small vehicles, and stationary structures. RESULTS: A final system was demonstrated using one off-highway haul truck, three smaller vehicles, and various stationary structures at a surface mining operation. The system successfully displayed the location of nearby vehicles and stationary structures and provided visual and audible warnings to the equipment operator when they were within a preset distance. SUMMARY: Many surface mining operations already use GPS technology on their mobile equipment for tracking and dispatch. Our tests have shown that it is feasible to add proximity warning to these existing systems as a safety feature. Larger scale and long-term tests are needed to prove the technology adequately. IMPACT ON INDUSTRY: A PWSs that incorporates a combination of technologies could significantly reduce accidents that involve collisions or driving over an edge at surface mining operations.  相似文献   
200.
This article discusses the development of corporate social responsibility (CSR) in Brazil from the perspective of the Ethos Institute of Business and Social Responsibility. The Institute is a not‐for‐profit, non‐governmental organization, that has played a leading role in the Brazilian CSR effort. In Brazil, CSR initiatives have a long tradition of philanthropy, a consequence of the country's great social inequalities. The increased attention to corporate social responsibility has paralleled growing concern about sustainable development and the intensifying activities of pressure groups (consumers, customers, investors, NGOs, labour unions, the media, among others) that have been increasing since the 1990s as natural resources are progressively becoming exhausted, social tensions rising and environmental conditions deteriorating worldwide. This article identifies problems and obstacles to the growth of corporate social responsibility in Brazil, as well as advances and alternatives for CSR and towards creating conditions for the country to be internationally competitive and sustainable in the financial, social and environmental areas.  相似文献   
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