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   76篇
  免费   6篇
  国内免费   23篇
安全科学   6篇
废物处理   3篇
环保管理   23篇
综合类   47篇
基础理论   9篇
污染及防治   3篇
评价与监测   6篇
社会与环境   6篇
灾害及防治   2篇
  2024年   1篇
  2021年   1篇
  2019年   1篇
  2018年   1篇
  2017年   1篇
  2016年   3篇
  2015年   1篇
  2014年   2篇
  2013年   6篇
  2012年   6篇
  2011年   7篇
  2010年   5篇
  2009年   4篇
  2008年   4篇
  2007年   10篇
  2006年   1篇
  2004年   5篇
  2003年   5篇
  2002年   5篇
  2001年   6篇
  2000年   9篇
  1999年   4篇
  1998年   3篇
  1997年   5篇
  1996年   2篇
  1994年   2篇
  1993年   1篇
  1992年   3篇
  1981年   1篇
排序方式: 共有105条查询结果,搜索用时 15 毫秒
71.
北京减河-潮白河水系的浮游植物与水质分析   总被引:2,自引:1,他引:1  
2009年的调查结果显示,在北京减河-潮白河(顺义段)水系的10个监测断面中共检出浮游植物6门72种,其中蓝藻、绿藻、硅藻种数分别占20.8%、38.9%、27.8%。Shannon-Weaver多样性指数为1.45~2.42, 属中度污染。浮游植物平均密度为2991.17×104cells/L, 其中蓝藻、绿藻、硅藻分别占73.6%、8.1%、13.9%,群落中的优势种群均为耐有机污染的富营养型水体指示种。该水系6项理化指标(SD、TN、TP、CODCr、BOD5、 Chla )的TSIM值为86.02~89.66,属于富营养型水体,主要污染物是TP、TN、CODCr。在物理、化学和生物因素的综合作用下TN、TP含量在该水系中的降低率分别为79.36%,74.29%。浮游植物密度与CODCr、Chla呈极显著正相关(P<0.01)。  相似文献   
72.
红碱淖是中国最大、最年轻的沙漠淡水湖,水域面积67平方公里。通过数据收集统计及打分计算的方式对红碱淖水环境质量、生态环境质量、水生态健康进行定量分析,结果表明,红碱淖水环境质量从1981年至2010年有逐渐恶化的趋势;2010年红碱淖生态系统健康综合指数为59.86,属于中等水平,已经受到了一定影响;生态质量综合评价值为81.6分,具有较高的保护价值。并对造成红碱淖水质和生态系统逐步恶化的原因进行解析,同时提出相应的对策。  相似文献   
73.
为修订中国大陆《职业病目录》提供参考意见,通过循证决策分析,比较中国香港特别行政区职业病名单和中国大陆《职业病目录》的异同点和优劣势,探讨香港职业病名单制度实践经验。结果表明,两地职业病名单在立法程序、地位与作用、分类方法存在一致性,在列举方式、法律依据、制定机构、分类及覆盖范围方面有所不同。特别是中国大陆生物因素所致职业病及职业性肌肉骨骼疾病覆盖范围较窄。在修订《职业病目录》时,应根据社会经济发展需求,结合社会保障能力,逐渐扩大职业病覆盖范围,以适应职业病防治工作的需求。  相似文献   
74.
主要介绍了香港政府为改善水环境而采取的综合措施 ,对我国水环境保护有一定借鉴意义  相似文献   
75.
洪湖表层沉积物中有机氯农药的含量及组成   总被引:16,自引:5,他引:11       下载免费PDF全文
利用GC-ECD测定了洪湖表层(0~2cm)、次表层(2~10cm)沉积物中有机氯农药的含量,并对其分布、组成及来源进行了探讨.结果表明,HCHs在表层、次表层沉积物中的含量分别为2.05~19.0ng/g和0.66~11.3ng/g,DDTs在表层、次表层沉积物中的含量分别为2.39~25.8ng/g和1.22~27.5ng/g.次表层沉积物中的有机氯农药含量低于表层沉积物,可能是因为有部分已发生迁移或转化.HCHs和DDTs呈现出在河流入湖口处含量较高,近长江处含量降低的趋势,其污染来源主要是河流输入及洪湖市的工农业排污.组分特征表明沉积物中的HCHs主要来源于林丹的使用,而DDTs则主要来源于环境早期残留.  相似文献   
76.
The increasing environmental awareness caused by the green movement has led to changes in attitude towards our traditionally wasteful society. Recent surveys in Hong Kong have shown that waste recycling has gained increasing verbal support among its citizens. This paper reports on recent findings which reveals that some discrepancies exist between people's attitude and behaviour towards waste recycling. The implication of this phenomenon on how and when a waste recycling policy should be carried out is considerable. Two major types of barriers to waste recycling and reduction were evident. Technical barriers to recycling included lack of appropriate information, lack of conveniently located bins and of temporary storage space, whilst the most critical barrier to paper waste recycling was the presence of non-recyclable materials in some paper items. Psychological barriers included the attitude of being troubled, and that too little waste was involved to be worth the effort. Technical barriers were found to dominate in commercial paper waste recycling, and can usually be overcome while psychological barriers were more significant in household waste recycling and are more difficult to solve. Thus, it might be concluded that, if a large scale household waste recycling programme were in place in Hong Kong, more effort should be devoted towards educating the public, to eliminate as many psychological barriers as possible. Findings from attitude surveys on recycling can provide valuable information for policy makers. However, a review of the literature indicates that findings from attitudinal and self-reported behavioural surveys may exaggerate the proportion of those who have a favourable attitude towards the surveyed subject matter. Thus, it is prudent for policy makers to consider the response rate of the surveys also.  相似文献   
77.
On domestic waste recycling, it was found that source separation of domestic waste in mainland China was supported by 85% of the urban population and about 11–13% of the household waste was recovered and sold by the householders for financial gains. It was also found that the lower income group tended to recover a greater portion of waste, indicating that voluntary waste recovery activities in mainland China were carried out largely due to economic reasons. Thus, the Western type of source separation program in which residents are requested to separate recyclables for the community may not be welcomed in mainland China. In Hong Kong, despite the presence of community waste recovery programs, the recovery of domestic waste is only about 6% and is therefore less than those of the mainland Chinese cities surveyed. On the choice of source separation programs, it was found that Hong Kong people ranked familiarity a more important criterion than convenience. Therefore, the collection frequency of recyclables and time and place for setting out recyclables should be as similar to those of normal waste collection as possible to attract high participation in source separation programs.  相似文献   
78.
A systematic postal survey of 449 schools in Hong Kong (including kindergartens, primary and secondary schools) was conducted to investigate the use of environmental education teaching kits and to obtain feedback from teachers about the view and comments in using these kits. Results indicated that kindergartens used teaching kits more frequently than secondary and primary schools. Most of the schools found the existing teaching kits helpful. Appropriate content, updated information, attractiveness to students and inclusion of a teachers' guide were considered important criteria in deciding the use of the teaching kits. Good illustrations, quality production and appropriate duration for the class were considered important factors too. The tight teaching schedule was the major hindrance for secondary and primary schools in the use of the environmental teaching kits. However, the main hindrance for using environmental teaching kits in kindergartens was that they did not have sufficient copies. Hong Kong schools would like to see new teaching kits about waste recycling, energy conservation, green behaviour, air pollution, noise pollution, sewage treatment and wildlife endangering, focusing on Hong Kong and China.  相似文献   
79.
香港、广州、佛山和北京市政垃圾的成分比较及处理策略   总被引:15,自引:1,他引:14  
现场采样分析了佛山市市政垃圾的组成和性质,比较了香港,广州,佛山和北京等4个城市市政垃圾的特征。4个城市的市政垃圾的组成和性质差别很大,北京市市政垃圾的煤灰含量很高,而香港的市政垃圾的张纸和塑料所占的百分比最大,根据香港固体废弃物的管理经验,广东省城市市政垃圾的处理方式和《中国二十一世纪仪程》,讨论了中国城市市政垃圾的性质和管理策略。  相似文献   
80.
The total carbon(C) and total nitrogen(N) content of suspended matter in a small undisturbed headwater drainage basin in the New Territories of Hong Kong has been monitored. Mean C and N contents were 12.85 % and 0.99% respectively for 132 samples. Samples collected under stableflow conditions had mean C and N contents of 12.81% and 1.06% respectively. Stormflow samples had mean C and N values of 12.86% and 0.97% respectively,which were very similar to the levels observed under stableflow conditions. The mean C: N ratios of 12.47 and 13.39 for stableflow and stormflow also reveal little difference according to hydrologic conditions. When all the data is considered little difference is observed in C and N according to the season. However, in winter there is a significant difference in C and N content between stable and stormflow samples. When C and N are plotted against water level the scattergraphs suggested that as stage increases the percentage of C and N in the suspended matter declines.Scattergraphs of C and N against suspended sediment concentration reveal a negative association. Comparison has been made between fresh leaf C, N and C/N ratio for trees and shrubs and the suspended matter. Fresh leaves do not appear to contribute significantly to suspended matter. The C/N ratio of suspended matter would also seem to exclude woody material and algae as sources of suspended matter.  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