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161.
In the routine São Paulo state (Brazil) surface water quality-monitoring program, which includes the Salmonella microsome mutagenicity assay as one of its parameters, a river where water is taken and treated for drinking water purposes has repeatedly shown mutagenic activity. A textile dyeing facility employing azo-type dyes was the only identifiable source of mutagenic compounds. We extracted the river and drinking water samples with XAD4 at neutral and acidic pH and with blue rayon, which selectively adsorbs polycyclic compounds. We tested the industrial effluent, raw, and treated water and sediment samples with YG1041 and YG1042 and compared the results with the TA98 and TA100 strains. The elevated mutagenicity detected with YG-strains suggested that nitroaromatics and/or aromatic amines were causing the mutagenicity detected in the samples analyzed. Positive responses for the blue rayon extracts indicated that mutagenic polycyclic compounds were present in the water samples analyzed. The mutagen or mixture of mutagens present in the effluent and water samples cause mainly frameshift mutations and are positive with and without metabolic activation. The Salmonella assay combined with different extraction procedures proved to be very useful in the identification of the origin of the pollution and in the identification of the classes of chemical compounds causing the mutagenic activity in the river analyzed.  相似文献   
162.
环境中全氟有机物的毒性、检测分析及降解   总被引:1,自引:0,他引:1  
自全氟有机物广泛使用50多年以来,已经在世界范围内发现一定浓度的全氟有机物,各国研究人员针对该类物质特别是全氟辛酸(PFOA)、全氟辛烷基磺酸(PFOS)进行了一定的研究.介绍了该类物质的污染现状,阐述了全氟有机物的毒性、检测分析技术及降解技术,在此基础上提出了今后的研究方向.  相似文献   
163.
The Irish Sea's distinctive hydrographic features present unique opportunities for research into the complex processes that regulate shelf-sea ecosystems. Such studies are essential in developing capabilities to detect and evaluate change in marine environments. A 1993 review showed almost 230 projects underway on the Irish Sea, spanning all the major fields of marine science. But a large proportion of research projects failed to indicate the purpose of the work; overall, there was a remarkable absence of clarity and specificity in the objectives. Progress in some fields is also hampered by insufficient coordination and cohesion; at present there are no standing arrangements between Ireland and the United Kingdom that provide for bilateral, co-ordination of scientific work in the area. There is clearly a need for a more planned and integrated Irish Sea science programme to provide information for management purposes and also to advance scientific understanding of the components and functions of Irish Sea ecosystems, and how and why they change with time. There is a common belief that the first of these predominantly involves monitoring, and the second research. However, the paper cautions that this is a dubious and unnecessary distinction. A strategy aimed at better integration of research and monitoring (e.g. a framework of linked objectives and targets) could substantially increase the information dividend from current investments in Irish Sea science. Based on a joint Irish/UK review, this paper outlines studies and approaches that are seen as key elements of a future, more relevant and costeffective research programme for the Irish Sea.  相似文献   
164.
The disposal of maintenance dredged material constitutes one of the most important problems in coastal zone management. To minimise ecological impacts, a number of ‘beneficial use’ options have developed whereby the material is regarded as a potential resource and used to recharge or recreate intertidal habitats. This paper presents the results of a sampling programme to investigate the macrofaunal recovery rates, and the underlying mechanisms responsible for them, following a beneficial use scheme involving the placement of fine-grained dredged material on a salt marsh in southeast England. Three stations in the recharge area and three reference stations, located within the same salt marsh system, were selected. These stations were sampled prior to recharge (recharge stations only) then 1 week, 3, 6, 12 and 18 months after the recharge. Sediment redox potentials (1, 2 and 4 cm sediment depths) were also measured on each sampling occasion. The results indicated a rapid recolonization of the fauna typical of the surrounding salt marsh channels. All univariate parameters had recovered after 3 months after the recharge. Active post-juvenile immigration is likely to have been the predominant recovery process. Multivariate data analysis revealed that the community structure of the recharge stations, however, did not progress towards those of the reference sites. Natural spatial variability in community structure at the scale of the recharge-reference station distance, and differences in eventual tidal elevations are factors responsible for these differences. The need to carefully assess reference site suitability in monitoring beneficial use schemes is discussed.  相似文献   
165.
基于监测样本信息的水环境系统权重分配方法   总被引:4,自引:0,他引:4  
针对水环境系统权重分配问题,从建筑系统客观背景入手,以环境因子监测样本资料为信息源,通过构造关联信息矩阵,并采用旋转正交转变换的主成分分析法,定量地描述了交五因子在整体系统的贡献,最后依贡献量大小识别对应各个因子的权重值,实例表明,该方法物理意义清晰结果客观合理。  相似文献   
166.
大气污染预测预报研究   总被引:1,自引:0,他引:1  
以排放到大气环境中的烟尘为例,进行大气污染预测预报,并利用保证率的概念表示预测的结果,为大气污染的预测预报工作提供了一种基本方法。  相似文献   
167.
环境噪声监测与分析   总被引:4,自引:0,他引:4  
在大量的资料进行了整理分析的基础上,叙述了近几年重庆市渝中区环境噪声控制所取得的进展,并提出进一步改善声环境质量的一些建议。  相似文献   
168.
Household waste prevention in England has been recognised in national strategy as a key component for future sustainable practice. To support the policy agenda, the Department of Environment, Food and Rural Affairs (Defra) in England has funded an extensive programme of fundamental research in the area. The specific research aim reported on here, in this Defra funded project, was to trial and assess methods for monitoring and evaluating approaches detailed in the National Resource and Waste Forum (NRWF)’s Household Waste Prevention Toolkit. The methods that formed the basis for the four research Objectives for the project were: using pilot and control areas (core Objective), tracking waste arisings, measuring specific activities and declared awareness and behaviour surveys. A primary objective of this research was to quantify the direct waste tonnage impacts of implementing a targeted household waste campaign in Dorset County, UK. A key performance indicator chosen for this assessment was the weight of waste collected at the kerbside from households. In an area where a waste prevention campaign is well planned and implemented then reductions in household waste arisings in pilot areas can be in the region of 2% per annum. This method for monitoring can be used, in the hands of an expert project team, to communicate to the public the direct benefits of waste prevention. It was found that there are a wide range of factors that need to be taken into account in the UK, and that these had hitherto been given little prominence, such as careful matching of pilot and control areas – this proved problematical in this research. However, a range of techniques used to support the methods, e.g. doorstepping surveys and focus groups could not show clear attributable waste prevention impacts but their findings could be used to direct new future messages to the public. The most successful and measurable campaign activities that were revealed by evaluation were: mail preference registrations, Home composting and doorstepping. An expert evaluation of all major methods found that no clear preference was revealed as to which were the most useful. None of the methods were judged very poor neither very good, all had major issues about their use. Tracking waste arisings and focus groups were assessed to be the best techniques in terms of input effort to output value. It is likely that waste prevention teams for household waste will need very careful training in the cost-effective use of the NRWF Toolkit before they are competent to apply it to a given place; the issues are more complex than were first thought.  相似文献   
169.

A new approach to surface water analysis has been investigated in order to enhance the detection of different organic contaminants in Nathan Creek, British Columbia. Water samples from Nathan Creek were prepared by liquid/liquid extraction using dichloromethane (DCM) as an extraction solvent and analyzed by gas chromatography mass spectrometry method in scan mode (GC-MS scan). To increase sensitivity for pesticides detection, acquired scan data were further analyzed by Automated Mass Spectrometry Deconvolution and Identification Software (AMDIS) incorporated into the Agilent Deconvolution Reporting Software (DRS), which also includes mass spectral libraries for 567 pesticides. Extracts were reanalyzed by gas chromatography mass spectrometry single ion monitoring (GC-MS-SIM) to confirm and quantitate detected pesticides. Pesticides: atrazine, dimethoate, diazinone, metalaxyl, myclobutanil, napropamide, oxadiazon, propazine and simazine were detected at three sampling sites on the mainstream of the Nathan Creek. Results of the study are further discussed in terms of detectivity and identification level for each pesticide found. The proposed approach of monitoring pesticides in surface waters enables their detection and identification at trace levels.  相似文献   
170.
仇开涛 《环境与发展》2020,(2):162-162,164
环境监测体制直接影响到我国环境管理质量,近几年环境污染问题受到社会各界的广泛重视,提高监测力度可有效提高环境保护效率。本文将结合现行制度特点,讨论强化人员队伍、更新保护机制、集成现有资源、社会监督宣传、完善法律问责、使用信息化系统等制度构建策略,为推进制度落实提供参考与借鉴。  相似文献   
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