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   163篇
  免费   1篇
  国内免费   4篇
安全科学   11篇
废物处理   3篇
环保管理   25篇
综合类   33篇
基础理论   43篇
污染及防治   36篇
评价与监测   8篇
社会与环境   7篇
灾害及防治   2篇
  2023年   4篇
  2022年   2篇
  2021年   2篇
  2020年   3篇
  2019年   3篇
  2018年   2篇
  2017年   3篇
  2016年   12篇
  2015年   7篇
  2014年   8篇
  2013年   19篇
  2012年   8篇
  2011年   12篇
  2010年   7篇
  2009年   10篇
  2008年   12篇
  2007年   6篇
  2006年   8篇
  2005年   7篇
  2004年   7篇
  2002年   2篇
  2001年   2篇
  1999年   2篇
  1998年   4篇
  1997年   1篇
  1996年   2篇
  1995年   3篇
  1993年   1篇
  1992年   1篇
  1991年   2篇
  1990年   1篇
  1989年   2篇
  1981年   2篇
  1958年   1篇
排序方式: 共有168条查询结果,搜索用时 62 毫秒
101.
Genotoxic potential of two environmental compartments (water and sediment) from the Upper Silesia Coal Basin (USCB), Poland were evaluated and compared by employing root meristem cells of Allium cepa. The clear genotoxic effect of water and sediment sampled was shown, with an important contribution of severe types of cytogenetic abnormalities. The most biologically relevant pollutants were revealed through multivariate statistical analysis of relationships between biological effects registered and the environment contamination. Overall, results of simultaneous use of conventional monitoring methods and biological tests suggested that contemporary levels of persistent pollutants in post-mining areas of the USCB may enhance the risk both for human health and biological components of natural ecosystems.  相似文献   
102.
Several community gardens have been developed in Edinburgh over the past five years, which reflects renewed interest in “grow your own” projects, and the recognition of the associated environmental and social health benefits they provide. Community gardens have been included in a range of policy documents at national and local levels, acknowledging their contribution to sustainable food systems, health and well-being and environment and biodiversity. This research explores how public policy influences community garden practice and, reflexively, how organisations running community gardens in the third sector are represented in public policy frameworks. A mixed methodology of desk-based research of policy documents, associated reports and academic literature; and informal interviews with community gardens staff and organisers was utilised. It was found that while community gardens are represented in policy, at a national level the framing of community gardens and related food growing projects as “alternative” hinders their full potential. Community gardens fulfil a wide range of policy goals, particularly in the health, social capital and well-being sectors which can minimise their capacity to contribute to local food production in a substantial way. It is proposed that community gardens could be normalised by promoting gardens in visible locations in neighbourhoods and within local plans; and through reflexive strategic and community action utilising a reasoning backwards approach to planning and funding.  相似文献   
103.
Although a number of comprehensive reviews have examined global ecosystem services (ES), few have focused on studies that assess urban ecosystem services (UES). Given that more than half of the world’s population lives in cities, understanding the dualism of the provision of and need for UES is of critical importance. Which UES are the focus of research, and what types of urban land use are examined? Are models or decision support systems used to assess the provision of UES? Are trade-offs considered? Do studies of UES engage stakeholders? To address these questions, we analyzed 217 papers derived from an ISI Web of Knowledge search using a set of standardized criteria. The results indicate that most UES studies have been undertaken in Europe, North America, and China, at city scale. Assessment methods involve bio-physical models, Geographical Information Systems, and valuation, but few study findings have been implemented as land use policy.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0504-0) contains supplementary material, which is available to authorized users.  相似文献   
104.
Total mercury (Hg) and monomethylmercury (MMHg) were analysed in the gills, liver and muscle of four cartilaginous fish species (top predators), namely, the eagle ray (Myliobatis aquila), the bull ray (Pteromylaeus bovinus), the pelagic stingray (Dasyatis violacea) and the common stingray (Dasyatis pastinaca), collected in the Gulf of Trieste, one of the most Hg-polluted areas in the Mediterranean and worldwide due to past mining activity in Idrija (West Slovenia). The highest Hg and MMHg concentrations expressed on a dry weight (d.w.) basis were found in the muscle of the pelagic stingray (mean, 2.529 mg/kg; range, 1.179–4.398 mg/kg, d.w.), followed by the bull ray (mean, 1.582 mg/kg; range, 0.129–3.050 mg/kg d.w.) and the eagle ray (mean, 0.222 mg/kg; range, 0.070–0.467 mg/kg, d.w.). Only one specimen of the common stingray was analysed, with a mean value in the muscle of 1.596 mg/kg, d.w. Hg and MMHg contents in the bull ray were found to be positively correlated with species length and weight. The highest MMHg accumulation was found in muscle tissue. Hg and MMHg were also found in two embryos of a bull ray, indicating Hg transfer from the mother during pregnancy. The number of specimens and the size coverage of the bull rays allowed an assessment of Hg accumulation with age. It was shown that in bigger bull ray specimens, the high uptake of inorganic Hg in the liver and the slower MMHg increase in the muscle were most probably due to the demethylation of MMHg in the liver. The highest Hg and MMHg contents in all organs were found in the pelagic stingray, which first appeared in the northern Adriatic in 1999. High Hg and MMHg concentrations were also found in prey species such as the banded murex (Hexaplex trunculus), the principal prey of the eagle rays and bull rays, the anchovy (Engraulis encrasicholus) and the red bandfish (Cepola rubescens), which are preyed upon by the pelagic stingray, as well as in zooplankton and seawater. Based on previously published data, a tentative estimation of MMHg bioamagnification was established. The average increase in MMHg between seawater, including phytoplankton, and zooplankton in the Gulf was about 104, and MMHg in anchovy was about 50-fold higher than in zooplankton. The bioaccumulation of MMHg between seawater and small pelagic fish (anchovy) amounted to 106 and between water and the muscle of larger pelagic fish (pelagic stingray) to 107. The MMHg increase between surface sediment and benthic invertebrates (murex) and between benthic invertebrates and small benthic fish was 102. Ultimately, the trophic transfer resulted in a 103 accumulation of MMHg between water and muscle of larger benthic fish (bull ray, eagle ray, common stingray), suggesting lower bioaccumulation by benthic feeding species.  相似文献   
105.
Increasing eutrophication and algal bloom events in the Yangtze River Three Gorges Reservoir, China, are widely discussed with regard to changed hydrodynamics and nutrient transport and distribution processes. Insights into water exchange and interaction processes between water masses related to large-scale water level fluctuations in the reservoir are crucial to understand water quality and eutrophication dynamics. Therefore, confluence zones of tributaries with the Yangtze River main stream are dedicated key interfaces. In this study, water quality data were recorded in situ and on-line in varying depths with the MINIBAT towed underwater multi-sensor system in the confluence zone of the Daning River and the Yangtze River close to Wushan City during 1 week in August 2011. Geostatistical evaluation of the water quality data was performed, and results were compared to phosphorus contents of selective water samples. The strongly rising water level throughout the measurement period caused Yangtze River water masses to flow upstream into the tributary and supply their higher nutrient and particulate loads into the tributary water body. Rapid algal growth and sedimentation occurred immediately when hydrodynamic conditions in the confluence zone became more serene again. Consequently, water from the Yangtze River main stream can play a key role in providing nutrients to the algal bloom stricken water bodies of its tributaries.  相似文献   
106.
Efficient composting process requires set of adequate parameters among which physical–chemical properties of the composting substrate play the key-role. Combining different types of biodegradable solid waste it is possible to obtain a substrate eligible to microorganisms in the composting process. In this work the composting of apple and tobacco solid waste mixture (1:7, dry weight) was explored. The aim of the work was to investigate an efficiency of biodegradation of the given mixture and to characterize incurred raw compost. Composting was conducted in 24 L thermally insulated column reactor at airflow rate of 1.1 L min?1. During 22 days several parameters were closely monitored: temperature and mass of the substrate, volatile solids content, C/N ratio and pH-value of the mixture and oxygen consumption. The composting of the apple and tobacco waste resulted with high degradation of the volatile solids (53.1%). During the experiment 1.76 kg of oxygen was consumed and the C/N ratio of the product was 11.6. The obtained temperature curve was almost a “mirror image” of the oxygen concentration curve while the peak values of the temperature were occurred 9.5 h after the peak oxygen consumption.  相似文献   
107.
108.
/ We investigated the notion that successful negotiations require that all parties to the dispute must have a desire to bargain. This desire is most likely to be present when the dispute exhibits ripeness and each party believes a bargained solution is the most cost-effective way to resolve differences. Structured interviews of participants in six Federal Energy Regulatory Commission hydropower licensing consultations were conducted to determine the level of need to negotiate for each party. The findings indicate that a need to negotiate is a necessary, but not sufficient, condition for success. Several factors were associated with a need to negotiate: a weak BATNA (best alternative to a negotiated agreement); a salient issue; participants' sense of efficacy; a sense of inevitability; professional roles encouraging negotiation; and disputes about facts as opposed to disputes about values. Participants' need to negotiate fluctuated throughout the process and intensified when questions were ripe: i.e., critical issues were debated or the regulatory process required action.KEY WORDS: Alternative dispute resolution; Federal licenses; Federal Energy Regulatory Commission; Instream flow; Environmental planning  相似文献   
109.
110.
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