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   98篇
  免费   2篇
  国内免费   3篇
安全科学   4篇
废物处理   5篇
环保管理   41篇
综合类   30篇
基础理论   2篇
污染及防治   9篇
评价与监测   4篇
社会与环境   3篇
灾害及防治   5篇
  2022年   1篇
  2018年   1篇
  2017年   3篇
  2016年   2篇
  2015年   5篇
  2014年   3篇
  2013年   6篇
  2012年   2篇
  2011年   5篇
  2010年   2篇
  2009年   9篇
  2008年   9篇
  2007年   5篇
  2006年   4篇
  2005年   7篇
  2004年   1篇
  2003年   5篇
  2001年   5篇
  2000年   6篇
  1999年   4篇
  1998年   2篇
  1997年   2篇
  1996年   3篇
  1993年   4篇
  1992年   2篇
  1991年   1篇
  1989年   1篇
  1986年   1篇
  1985年   1篇
  1977年   1篇
排序方式: 共有103条查询结果,搜索用时 15 毫秒
31.
Solid waste generation and its implications for people and the environment are global issues. The complexity of the waste composition and the ever-increasing percapita waste generation is a challenge for waste managers, particularly in developing countries. Thus, the need to have a clear policy on waste management and legislation to realize that policy is imperative. Malaysia is developing rapidly and problems such as the waste generation associated with development and industrialization are evident. The Solid Waste and Public Cleansing Management Bill, which was approved in August 2007 after a 10-year delay, is envisaged to have serious consequences in waste management practices and implementation in Malaysia. This article explores the main features of this all-encompassing bill and its impacts on the waste management scenario in Malaysia. In addition, a comparative evaluation is also discussed to explore the policies/legislation of selected countries vis-àvis the Malaysian bill.  相似文献   
32.
Providing good solid waste management (SWM) services while also ensuring financial sustainability of the system continues to be a major challenge in cities of developing countries. Bahir Dar in northwestern Ethiopia outsourced municipal waste services to a private waste company in 2008. While this institutional change has led to substantial improvement in the cleanliness of the city, its financial sustainability remains unclear. Is the private company able to generate sufficient revenues from their activities to offset the costs and generate some profit?This paper presents a cost-revenue analysis, based on data from July 2009 to June 2011. The analysis reveals that overall costs in Bahir Dar’s SWM system increased significantly during this period, mainly due to rising costs related to waste transportation. On the other hand, there is only one major revenue stream in place: the waste collection fee from households, commercial enterprises and institutions. As the efficiency of fee collection from households is only around 50%, the total amount of revenues are not sufficient to cover the running costs. This results in a substantial yearly deficit. The results of the research therefore show that a more detailed cost structure and cost-revenue analysis of this waste management service is important with appropriate measures, either by the privates sector itself or with the support of the local authorities, in order to enhance cost efficiency and balance the cost-revenues towards cost recovery. Delays in mitigating the evident financial deficit could else endanger the public-private partnership (PPP) and lead to failure of this setup in the medium to long term, thus also endangering the now existing improved and currently reliable service.We present four options on how financial sustainability of the SWM system in Bahir Dar might be enhanced: (i) improved fee collection efficiency by linking the fees of solid waste collection to water supply; (ii) increasing the value chain by sales of organic waste recycling products; (iii) diversifying revenue streams and financing mechanisms (polluter-pays-, cross-subsidy- and business-principles); and (iv) cost reduction and improved cost-effectiveness.We argue that in a PPP setup such as in Bahir Dar, a strong alliance between the municipality and private enterprise is important so that appropriate solutions for improved financial sustainability of a SWM system can be sought and implemented.  相似文献   
33.
Dunlop PS  Ciavola M  Rizzo L  Byrne JA 《Chemosphere》2011,85(7):1160-1166
Solar disinfection (SODIS) of Escherichia coli suspensions in low-density polyethylene bag reactors was investigated as a low-cost disinfection method suitable for application in developing countries. The efficiency of a range of SODIS reactor configurations was examined (single skin (SS), double skin, black-backed single skin, silver-backed single skin (SBSS) and composite-backed single skin) using E. coli suspended in model and real surface water. Titanium dioxide was added to the reactors to improve the efficiency of the SODIS process. The effect of turbidity was also assessed. In addition to viable counts, E. coli injury was characterised through spread-plate analysis using selective and non-selective media. The optimal reactor configuration was determined to be the SBSS bag (t50 = 9.0 min) demonstrating the importance of UVA photons, as opposed to infrared in the SODIS disinfection mechanism. Complete inactivation (6.5-log) was achieved in the presence of turbidity (50 NTU) using the SBSS bag within 180 min simulated solar exposure. The addition of titanium dioxide (0.025 g L−1) significantly enhanced E. coli inactivation in the SS reactor, with 6-log inactivation observed within 90 min simulated solar exposure. During the early stages of both SODIS and photocatalytic disinfection, injured E. coli were detected; however, irreversible injury was caused and re-growth was not observed. Experiments under solar conditions were undertaken with total inactivation (6.5-log) observed in the SS reactor within 240 min, incomplete inactivation (4-log) was observed in SODIS bottles exposed to the same solar conditions.  相似文献   
34.
哈密地区生态环境十分脆弱,森林覆盖率低,草场退化严重,近几年经济发展速度加快,但重开发、轻保护,资源开发和经济增长方式粗放,使生态系统遭到破坏.为坚持科学的发展观,保证地区经济、社会实现可持续发展,哈密地委、行署提出了"生态立区"的发展战略.本文对哈密地区"生态立区"的内涵及实现的途径进行了探讨.  相似文献   
35.
Promoting stoves that burn wood and other biofuels more efficiently is one of the means to reduce fuel consumption, but such efficient stoves may also emit more carbon monoxide and total suspended particulates. In an earlier study, a standard chamber method was proposed to estimate emission factors from burning fuelwood (Acacia nilotica). Here that methodology is extended to measure emission factors from burning of dungcakes and crop residues (Brassica or mustard stalks)—common fuels in many developing countries. The amounts of carbon monoxide (CO) and total suspended particulates (TSP) emitted by four different models of stoves, when using each of the three biofuels, are measured.The CO emission factors range from 13–68 (g/kg) for fuelwood to 26–67 g/kg for dungcakes and 20–114 g/kg for crop residues, for particulates they range from 1.1–3.8 to 4.1–7.8 and 2.1–12.0 g/kg for the three fuels, respectively. On a per unit heat delivered basis, the emissions of CO and TSP from both dungcakes and crop residues are two to three times higher compared to those from fuelwood. While for some improved stove-fuel combinations, the increase in emission factors was offset by the increase in thermal efficiency, this was not always so and causes a dilemma. The more efficient stoves are found to have higher emission factors of both CO and TSP for all three fuels. Emissions per standard task (i.e, on a unit heat delivered basis) is proposed as a criterion to evaluate cookstoves.  相似文献   
36.
Conservation of living resources is no longer parochial in scope; it is a global challenge. Ecological, social, political, and business interests operate in a network that reaches across seas, continents, and nations. Industries, including the electric utility industry, are diversifying in products and expanding into international markets. They soon discover that, while all nations have common goals for their peoples, conservation and environmental issues in less-developed nations have different dimensions and norms than are encountered in Western, affluent societies. In developing countries, survival is more of an issue than quality of life, and burgeoning human numbers have put tremendous pressures on resources including wildlife and its habitats. Human population, urbanization of society, changes in single-species to ecosystem and landscape levels of management, and protectionists and animal rights philosophies are influences with which conservation of resources and the environment must contend. The human condition and conservation efforts are inextricably linked. Examples to demonstrate this fact are given for Project Tiger in India, the jaguar in Latin America, and the Serengeti ecosystem in Kenya and Tanzania.  相似文献   
37.
This study attempts to assess the impact of two different climatic shocks, drought and excessive rainfall/flood, as perceived by households on child human capital across four countries: Ethiopia, India, Peru and Vietnam – countries with diverse socio-economic backgrounds. Human capital, in this context, subsumes both child learning and health outcomes. The data source is the Young Lives Study and cross-sectional household data on the older cohort of children (between 14 and 16 years of age) are utilized, for the year 2009. The enrolment rate, Peabody Picture Vocabulary Test, Cloze test and Math test scores are used as proxies for child learning outcomes. The health outcome variables being studied are the WHO-defined Body Mass Index z-scores and Height for Age z-scores. The overall objective is to study heterogeneity in responses to shock in terms of the development of human capital across the set of countries considered. Additionally, the study elaborates on the role of institutional help, during crisis, and the role of household characteristics in buffering these climatic shocks.  相似文献   
38.
In spite of the wide diversity in the economic performance of small island developing states (SIDS), the apparent prosperity of several SIDS has entailed a global misrepresentation of the economic situation of these countries. While their vulnerability to natural disasters is not denied, the general risk of economic marginalization that many SIDS face in the context of globalization may not have received sufficient attention. The paper attempts to highlight what matters most in the consideration of the economic vulnerability of SIDS and in the debate to prevent their marginalization. It examines the main types of external shocks to which SIDS are vulnerable, and discusses the economic handicaps that are fundamental causes of this vulnerability. Economic specialization (with the predominance of international trade in services) is then a central notion in the analysis of island vulnerability: a better specialization, which may involve diversification and always implies greater international competitiveness, can reduce the exposure or vulnerability of SIDS to external shocks, and induce greater economic stability in these countries. Hence the importance of developing policies to circumvent the specific handicaps of islands and facilitate the realization of new trading opportunities through an emulative use of globalization forces.  相似文献   
39.
文章对近些年来的简易现场水质检测、水质自动监测等水质环境监测技术和仪器发展以及中间存在的问题作出了初步的分析,对国际上以及国内的一些水质环境监测技术的经验和成果进行了总结,对未来此技术的发展方向和重点指明了方向。  相似文献   
40.
At a global level, the relationship between biodiversity importance and capacity to manage it is often assumed to be negative, without much differentiation among the more than 200 countries and territories of the world. We examine this relationship using a database including terrestrial biodiversity, wealth and governance indicators for most countries. From these, principal components analysis was used to construct aggregated indicators at global and regional scales. Wealth, governance, and scientific capacity represent different skills and abilities in relation to biodiversity importance. Our results show that the relationship between biodiversity and the different factors is not simple: in most regions wealth and capacity varies positively with biodiversity, while governance vary negatively with biodiversity. However, these trends, to a certain extent, are concentrated in certain groups of nations and outlier countries. We discuss our results in the context of collaboration and joint efforts among biodiversity-rich countries and foreign agencies.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0581-0) contains supplementary material, which is available to authorized users.  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