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   431篇
  免费   11篇
  国内免费   26篇
安全科学   35篇
废物处理   2篇
环保管理   145篇
综合类   156篇
基础理论   44篇
污染及防治   25篇
评价与监测   23篇
社会与环境   22篇
灾害及防治   16篇
  2023年   5篇
  2022年   5篇
  2021年   17篇
  2020年   22篇
  2019年   7篇
  2018年   12篇
  2017年   13篇
  2016年   16篇
  2015年   17篇
  2014年   17篇
  2013年   28篇
  2012年   18篇
  2011年   19篇
  2010年   23篇
  2009年   19篇
  2008年   22篇
  2007年   16篇
  2006年   16篇
  2005年   15篇
  2004年   9篇
  2003年   15篇
  2002年   12篇
  2001年   14篇
  2000年   16篇
  1999年   12篇
  1998年   10篇
  1997年   9篇
  1996年   4篇
  1995年   7篇
  1994年   4篇
  1993年   3篇
  1992年   3篇
  1990年   2篇
  1989年   4篇
  1988年   4篇
  1986年   5篇
  1985年   5篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1981年   2篇
  1980年   3篇
  1979年   4篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1974年   2篇
  1973年   1篇
  1971年   1篇
排序方式: 共有468条查询结果,搜索用时 15 毫秒
271.
Domestic gardens offer immense potential as sites for native biodiversity conservation. In urban areas they often comprise the largest land use, thus presenting an accessible and immediate way for urban dwellers to connect with nature and to support and enhance native biodiversity. This paper presents findings from a study of 55 domestic gardens undertaken in Dunedin, New Zealand, which explores householders' relationships with their gardens. The study data was derived from two interviews with householders, two photo exercises (approximately a year apart), together with a number of biological studies of the gardens. Gardens proved to be very important for our householders; for physical and mental health, as an expression of ownership and identity, as sites for social relationships, for connecting with nature and as site of domestic produce production. Householders' connections with nature were idiosyncratic, multifaceted and exhibited in ways that are more complex and varied than those usually considered by those working in the natural sciences and indeed biophilia supporters. We emphasize the importance of the people side of nature in seeking to build and support positive ecological change in the urban environment and the value of combining natural and social science approaches.  相似文献   
272.
Mitigation of the heat island effect in urban New Jersey   总被引:1,自引:0,他引:1  
Implementation of urban heat island (UHI) mitigation strategies such as increased vegetative cover and higher-albedo surface materials can reduce the impacts of biophysical hazards in cities, including heat stress related to elevated temperatures, air pollution and associated public health effects. Such strategies also can lower the demand for air-conditioning-related energy production. Since local impacts of global climate change may be intensified in areas with UHIs, mitigation strategies could play an increasingly important role as individuals and communities adapt to climate change. We use CITYgreen, a GIS-based modeling application, to estimate the potential benefits of urban vegetation and reflective roofs as UHI mitigation strategies for case study sites in and around Newark and Camden, New Jersey.

The analysis showed that urban vegetation can reduce health hazards associated with the UHI effect by removing pollutants from the air. Less affluent, inner-city neighborhoods are the ones in which the hazard potential of the UHI effect is shown to be greatest. However, these neighborhoods have less available open space for tree planting and therefore a lower maximum potential benefit. As the climate warms, these neighborhoods may face greater consequences due to interactions between the UHI effect and global climate change. Results also show that urban vegetation is an effective and economically efficient way to reduce energy consumption and costs at the sites.  相似文献   
273.
《Environmental Hazards》2013,12(2):147-166
Vulnerability is a central construct in environmental risk assessment, and a variety of methods have been introduced to facilitate its expression as a planning and decision-making device. The contrasting interpretations generated by these methods of modelling produce dramatic differences in spatial representation that contribute to uncertainty, and no clear connection has been established between vulnerability and the actual consequences resulting from a nature hazard event. In this study, geographic information system-based vulnerability modelling is evaluated, and the association between modelled-produced expressions and the aftermath impact of a natural hazard event on the human landscape is examined. Employing hurricane aftermath data from the 2005 Hurricane Katrina event in New Orleans, Louisiana, this study presents a comparative analysis that can assist in the validation of vulnerability assessment methods and identify limitations in current modelling strategies. The results of this analysis demonstrate that the methods employed to model vulnerability do not necessarily capture the actual consequence of a natural hazard event and suggest that place-specific factors should play a more significant role when assessing hazard vulnerability.  相似文献   
274.
蒸汽直埋管道的安全与节能技术近年来日趋成熟,但在南方高水位城市应用中还存在诸多缺陷。本文结合工程实践,针对这些缺陷进行了技术改进,并在多项工程中推广应用,取得了良好的效果。  相似文献   
275.
The Journal of Safety Research has partnered with the National Center for Injury Prevention and Control at the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, USA, to briefly report on some of the latest findings in the research community. This report is the fourth edition in a series of CDC articles. BACKGROUND: An active injury and illness surveillance system was established by the Centers for Disease Control and Prevention (CDC) along with the Louisiana Department of Health and Hospitals (LDHH) in the aftermath of Hurricane Katrina in functioning hospitals and medical clinics. RESULTS: The surveillance system recorded 7,543 nonfatal injuries among residents and relief workers between September 8-October 14, 2005. The leading mechanisms of injury identified in both groups were fall and cut/stab/pierce, with a greater proportion of residents compared to relief workers injured during the repopulation period. Clean-up was the most common activity at the time of injury for both groups. CONCLUSION: Injuries documented through this system underscore the need for surveillance of exposed populations to determine the injury burden and initiate injury prevention activities and health communication campaigns.  相似文献   
276.
277.
Predicting and preventing outbreaks of infectious disease in endangered wildlife is problematic without an understanding of the biotic and abiotic factors that influence pathogen transmission and the genetic variation of microorganisms within and between these highly modified host communities. We used a common commensal bacterium, Campylobacter spp., in endangered Takahe (Porphyrio hochstetteri) populations to develop a model with which to study pathogen dynamics in isolated wildlife populations connected through ongoing translocations. Takahe are endemic to New Zealand, where their total population is approximately 230 individuals. Takahe were translocated from a single remnant wild population to multiple offshore and mainland reserves. Several fragmented subpopulations are maintained and connected through regular translocations. We tested 118 Takahe from 8 locations for fecal Campylobacter spp. via culture and DNA extraction and used PCR for species assignment. Factors relating to population connectivity and host life history were explored using multivariate analytical methods to determine associations between host variables and bacterial prevalence. The apparent prevalence of Campylobacter spp. in Takahe was 99%, one of the highest reported in avian populations. Variation in prevalence was evident among Campylobacter species identified. C. sp. nova 1 (90%) colonized the majority of Takahe tested. Prevalence of C. jejuni (38%) and C. coli (24%) was different between Takahe subpopulations, and this difference was associated with factors related to population management, captivity, rearing environment, and the presence of agricultural practices in the location in which birds were sampled. Modeling results of Campylobacter spp. in Takahe metapopulations suggest that anthropogenic management of endangered species within altered environments may have unforeseen effects on microbial exposure, carriage, and disease risk. Translocation of wildlife between locations could have unpredictable consequences including the spread of novel microbes between isolated populations.  相似文献   
278.
为评估雄安新区农田土壤-农作物系统重金属潜在生态风险,分析测试新区小麦籽实和根系土壤中重金属含量及其赋存形态,利用综合污染指数(IPIN)、潜在生态风险指数(RI)、生物富集系数(BFC)和风险评价指数(RAC),采用主成分分析和相关分析等统计方法开展重金属潜在生态风险评估及来源解析.结果 表明,新区根系土壤中Cd、C...  相似文献   
279.
近年来,排污权有偿使用与交易制度在中国部分省份开展了试点工作,许多大型的规模化畜禽养殖场也进行了排污许可证的申领。针对新西兰奶牛养殖业的污染治理措施进行了研究,梳理其开展污染防治工作的措施体系,以陶泊湖周边施行的氮排放配额与交易为主要对象,阐述了新西兰在养殖业排放配额与交易制度方面的工作实践,其配额基准核定方法、"资源许可证"申领制度、配额交易体系、相关支撑措施在一定程度上具备优势和先进性,对中国的畜禽养殖污染减排工作具有借鉴意义。  相似文献   
280.
ABSTRACT: In current hydrologic practice flood frequency estimates are usually based upon either the annual or the partial duration series of floods. Recurrence intervals generated by each series are not equivalent, however, and conversion of recurrence intervals from one series to the other is usually achieved by reference to a mathematical function developed by Langbein in 1949. Data collected on the Murrumbidgee River in New South Wales suggest, however, that the Langbein conversion function does not always provide a reliable means of comparing recurrence intervals. For discharges more frequent than the three year annual flood the Langbein function understates the discrepancy between the two sets of recurrence interval by approximately 35 percent. Langbein's own North American data appear to be consistent with those collected on the Murrumbidgee River.  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