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831.
氮是水体中的主要污染物之一。近几十年来,随着工农业的发展,使得水体中氮的污染呈上升趋势,并在今后可能会持续,最根本的解决方法是找到源头,从根本上切断污染途径以达到消除氮源的污染。在查阅相关文献的基础上,阐述了水中用同位素追踪研究氮的来源的研究进展和存在的问题,对于评价氮的污染现状、污染控制和环境管理具有十分重要的意义。 相似文献
832.
833.
近年来,随着人们对废水处理和中水回用技术逐渐重视,一种将传统生物处理技术与膜分离技术结合起来的MBR工艺受到青睐。本文通过对RMBR、SMBR、HMBR应用原理及优缺点的分析。为实际应用提供参考。 相似文献
834.
835.
建立了简便、快速、有效的分散液液微萃取(DLLME)-气相色谱/质谱技术萃取水样中痕量阿特拉津的新方法。通过试验确定最佳萃取条件。 相似文献
836.
介绍了动力风泵房每年有大量的工业余热为没经过处理直接排放,造成能源的浪费,以及其解决的思路:利用水源热泵吸收动力风泵房中产生的余热来加热水源,变成洗浴用水,从而达到节能减排的目的. 相似文献
837.
系统介绍了秩相关系数的计算、检验及Excel计算模式,为环境质量报告书的编制及水质趋势变化分析提供了更加方便的方法。 相似文献
838.
Long-term changes of fish biotic integrity in the Sanmenxia Wetland,North China,since the 1950 s were assessed using the fish index of biological integrity(FIBI). The water and sediment quality was evaluated by the water quality index(WQI) and sediment pollution index(SPI). The results showed that FIBI continuously decreased from 46 to 20 during the past 5 decades,which indicated that the fish community state shifted from fair to very poor conditions,and damming by itself did not affect the fish biotic integrity. At the same time,WQI fell from 83 to 44.1,and SPI increased from 0.99 to 2.14 since the 1960 s,resulting from fast regional socio-economic development and insufficient wastewater treatment. Correlation analysis suggested that water quality significantly affected biotic integrity(r = 0.867,p 〈 0.05) through direct effects on the fish community. As a representative example of many wetlands in North China,our study clearly demonstrated that the biological integrity was degraded,induced both by water quality deterioration and sediment pollution,further driven by the contradiction between rapid development of regional economy and lagging development of sewage treatment facilities,which were thought to be the main factor responsible for the degradation of biological integrity. 相似文献
839.
Weible CM 《Environmental management》2007,40(6):853-865
What factors explain stakeholders’ perceptions of scientists in environmental politics? Questionnaire data are used to examine stakeholders’ views of scientific experts in the context of Lake Tahoe environmental policy from 1984 to 2001. Stakeholders’ perceptions of scientists have remained the same over time – despite a shift from adversarial to collaborative policymaking and after decades of mounting scientific evidence showing water quality declines. On average, stakeholders perceive scientists with limited influence on Lake Tahoe environmental policy and view them with mixed levels of skepticism. Stakeholders’ evaluation of scientists is best explained by their beliefs about development versus the environment. Stakeholders in favor of more land development express distrust of scientists and negatively evaluate university researchers and consultants. Stakeholders in favor of environmental protection are more likely to trust scientists and positively evaluate university researchers and consultants. 相似文献
840.
The performance of different policy design strategies is a key issue in evaluating programmes for water quality improvement
under the Water Framework Directive (60/2000). This issue is emphasised by information asymmetries between regulator and agents.
Using an economic model under asymmetric information, the aim of this paper is to compare the cost-effectiveness of selected
methods of designing payments to farmers in order to reduce nitrogen pollution in agriculture. A principal-agent model is
used, based on profit functions generated through farm-level linear programming. This allows a comparison of flat rate payments
and a menu of contracts developed through mechanism design. The model is tested in an area of Emilia Romagna (Italy) in two
policy contexts: Agenda 2000 and the 2003 Common Agricultural Policy (CAP) reform. The results show that different policy
design options lead to differences in policy costs as great as 200–400%, with clear advantages for the menu of contracts.
However, different policy scenarios may strongly affect such differences. Hence, the paper calls for greater attention to
the interplay between CAP scenarios and water quality measures. 相似文献