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   30篇
  免费   0篇
环保管理   4篇
综合类   6篇
基础理论   8篇
污染及防治   5篇
评价与监测   4篇
社会与环境   3篇
  2022年   1篇
  2021年   1篇
  2017年   2篇
  2016年   1篇
  2015年   2篇
  2014年   3篇
  2012年   1篇
  2011年   3篇
  2009年   1篇
  2006年   1篇
  2005年   1篇
  2003年   2篇
  2002年   1篇
  2001年   1篇
  2000年   1篇
  1997年   1篇
  1996年   1篇
  1994年   1篇
  1991年   1篇
  1990年   1篇
  1987年   1篇
  1970年   1篇
  1965年   1篇
排序方式: 共有30条查询结果,搜索用时 484 毫秒
1.
生物膜填料塔处理浓度有机废气的工业应用试验研究   总被引:2,自引:0,他引:2  
工业应用试验研究表明,生物膜填料塔处理工业有机废气是可行的,当运行条件控制适当时,净化效率可保持在90%以上,能够实现达标排放,这一成果填补了我国环保工业技术领域的空白,工程技术上接近现阶段国外的技术研究水平。  相似文献   
2.
The cold and arid mountains and plateaus of High Asia, inhabited by a relatively sparse human population, a high density of livestock, and wildlife such as the iconic snow leopard Panthera uncia, are usually considered low risk for disease outbreaks. However, based on current knowledge about drivers of disease emergence, we show that High Asia is rapidly developing conditions that favor increased emergence of infectious diseases and zoonoses. This is because of the existing prevalence of potentially serious pathogens in the system; intensifying environmental degradation; rapid changes in local ecological, socio-ecological, and socio-economic factors; and global risk intensifiers such as climate change and globalization. To better understand and manage the risks posed by diseases to humans, livestock, and wildlife, there is an urgent need for establishing a disease surveillance system and improving human and animal health care. Public health must be integrated with conservation programs, more ecologically sustainable development efforts and long-term disease surveillance.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01599-7.  相似文献   
3.
Opponents of a proposed sea-level-rise policy in North Carolina, USA, reasoned rhetorically to promote a narrative claiming that the policy supporters’ efforts had failed to meet the criteria of “good” science and the American dream expectancy of “progress.” The critics worked to hinder policy adoption by naming as “villains” scientists who provided research to support the proposed policy. In addition, the opponents named their own efforts to prevent policy based on “bad” science that would “destroy” the American dream as “heroic.” To more effectively respond to such narratives, scientists and policy proponents need to shift away from reporting just climate change “facts” in the attempt to gain stakeholder support for mitigation and adaptation initiatives. They need to move toward reasoning rhetorically to construct narratives that encourage the public to name them as the “heroes” who will achieve the American dream by their actions to mitigate climate-change outcomes.  相似文献   
4.
Spatial distribution of the pomacentrids on Singapore reefs was assessed visually, while temporal change was studied within permanent quadrats established on a patch reef between 4 Jul and 30 Nov 1989. Partitioning of space, both horizontally and vertically, on the reef was observed in 15 species. The population of territorial damselfishes on the reef flat was less stable than on the reef slope over time, due to the seasonal occurrence of dense stands of the brown macroalgae, Sargassum. Space was found to be a limiting factor at the reef flat due to the high density of pomacentrids found there. Food resource was the limiting factor on the reef slope, where low light intensity due to sedimentation and lack of suitable substrate inhibited turf algal growth. Multi-specific recruitment of juveniles occurred in April and between mid-October and early November.  相似文献   
5.
Choo TP  Lee CK  Low KS  Hishamuddin O 《Chemosphere》2006,62(6):961-967
This study describes an investigation using tropical water lilies (Nymphaea spontanea) to remove hexavalent chromium from aqueous solutions and electroplating waste. The results show that water lilies are capable of accumulating substantial amount of Cr(VI), up to 2.119 mg g(-1) from a 10 mg l(-1) solution. The roots of the plant accumulated the highest amount of Cr(VI) followed by leaves and petioles, indicating that roots play an important role in the bioremediation process. The maturity of the plant exerts a great effect on the removal and accumulation of Cr(VI). Plants of 9 weeks old accumulated the most Cr(VI) followed by those of 6 and 3 weeks old. The results also show that removal of Cr(VI) by water lilies is more efficient when the metal is present singly than in the presence of Cu(II) or in waste solution. This may be largely associated with more pronounced phytotoxicity effect on the biochemical changes in the plants and saturation of binding sites. Significant toxicity effect on the plant was evident as shown in the reduction of chlorophyll, protein and sugar contents in plants exposed to Cr(VI) in this investigation.  相似文献   
6.
A self-developed sewer health assessment system using the fuzzy comprehensive evaluation and analytical hierarchy process was applied to give a comprehensive health condition evaluation on part of the local sewers in a southern Chinese city based on the sewer video data collected by a sewer inspection closed circuit television (CCTV) robot. Aside from the overall condition evaluation, the structure, function, and stability status of the sewer were also analyzed using the method. A comprehensive index H was proposed to give the overall health condition of pipes with different defects, and Ht, Hs, and If were used to quantify the defects affecting the tightness, stability, and function of the pipe, respectively. Results show that 48% of the inspected pipes were in good condition (0〈H〈0.25), and about 33% of the sewer pipes analyzed were categorized to be at severe or urgent condition levels (H 〉 0.5), although most of the pipes were installed only within five years. Frequent sedimentation affects the function of the sewer, and deformation and joint damage affect the structure of the sewer.  相似文献   
7.
A study was carried out to investigate the fractionation of Cd, Cr, Cu, Fe, Mn, Pb, and Zn in shrimp aquaculture sludge from Selangor, Malaysia, using original (unmodified) and modified four-steps BCR (European Community Bureau of Reference, now known as the Standards Measurements and Testing Program) sequential extraction scheme. Step 2 of the unmodified BCR procedure (subsequently called Method A) involves treatment with 0.1 M hydroxylammonium chloride at pH 2, whereas 0.5 M hydroxylammonium chloride at pH 1.5 was used in the modified BCR procedure (subsequently called Method B). Metal analyses were carried out by flame atomic absorption spectrometry. A pseudo-total aqua-regia digest of BCR CRM 701 has also been undertaken for quality assurance purposes. The recovery of Method A for all metals studied ranges from 96.14% to 105.26%, while the recovery for Method B ranges from 95.94% to 122.40%. Our results reveal that Method A underestimated the proportion of metals bound to the easily reducible fraction except for copper. Therefore, the potential mobility of these elements is higher than others. Thus, to use this sludge as a fertilizer we have to first find a remediation for reduction of heavy metal contamination.  相似文献   
8.
9.
Accounting of carbon stocks in woody vegetation for greenhouse purposes requires definition of medium term trends with accurate error assessment. Tree and shrub cover was sampled through time at randomly located sites over a large area of central Queensland, Australia using aerial photography from 1945 to 1999. Calibration models developed from field data for the same land types as those represented within the study area allowed for the extrapolation of overstorey and understorey cover, basal area and biomass values and these were modelled as trends over the latter half of the 20th century. These structural attributes have declined over the region because of land clearing with values for biomass changing from a mean of 58.0(+/-1.2)t/ha in 1953 to 41.1(+/-1.0)t/ha in 1991. The biomass of Acacia on clay and Eucalypt on texture contrast soils land types has declined most dramatically. Within uncleared vegetation there was an overall trend of increase from 56.1(+/-1.2)t/ha in 1951 to 67.6(+/-1.3)t/ha in 1995. The increase in structural attributes within uncleared vegetation was most pronounced for the Eucalypt on texture contrast soils and Eucalypt on clay land types. It was demonstrated that the sites sampled were representative of their land types and that spatial bias of the photography, undetected tree-killing, sampling error, inherent variability of structural attributes and measurement error should not have impacted greatly on bias or precision of trend estimates for well-sampled land types. Certainly the errors are not likely to be substantial for trends averaged over all land types and they provide an accurate assessment of the magnitude and direction of change. The technique presented here would appear to be a robust means of accounting for the above-ground woody component of woodlands and open forests and will also contribute to a broader understanding of savanna dynamics.  相似文献   
10.
Dune slacks are important coastal sand dune habitats and seasonal changes in water levels within dune aquifers control both their formation and the specific hydrological conditions which then govern the floristic composition of their characteristic plant communities. Kenfig Dunes National Nature Reserve is one of the largest dune sites in South Wales and Southern Britain. It supports an exceptional range of dune slack communities, including most of those recognised in the British National Vegetation Classification scheme. Detailed studies of the vegetation ecology and hydrology of dune slacks reveal the important influence of hydrological variables in controlling the composition of dune slack vegetation and also valuable information on water table profile and the key factors governing the annual hydrological budget of the dune system aquifer.  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