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1.
As part of the monitoring program from Instituto Hidrográfico, since 1981 sediment and water samples have been collected from four different estuarine areas located along the continental coast of Portugal. The concentrations of different parameters were measured in the water and sediment samples. After normalization, the concentrations of chromium, mercury, lead and zinc in the sediments from the different areas were compared.  相似文献   

2.
用二级模糊评判模型评价环境质量状况   总被引:8,自引:1,他引:8  
用二级模糊评判模型评价区域环境质量状况,弥补了用一级模糊综合评判只可评价各点位环境质量状况的不足,是一种新的环境评价方法,评价结果与实际情况相符,效果良好,方法实用.  相似文献   

3.
Excel在水环境监测数据分析中的应用   总被引:1,自引:1,他引:1  
针对水环境监测数据分析中常用的制图、水质类别判断、综合污染指数计算和湖库富营养化指数计算等方面,用VBA语言编写了在Excel中运行的宏,以提高环境监测数据处理时自动化水平,提高工作效率。  相似文献   

4.
Monitoring of cyclic organochlorines in the marine environment   总被引:1,自引:0,他引:1  
Cyclic organochlorines are highly hydrophobic chemicals which usually possess a high persistence to microbial breakdown. These behavioural aspects determine the suitability of each environmental compartment for monitoring purposes, which is discussed.It is concluded, that monitoring of (cyclic) organochlorines should only be executed for compounds about which solid information is available on their environmental behaviour in abiotic and biotic environmental compartments. Under these conditions benthic invertebrates which use glycogen as their main energy-depot, appear to be the most suitable tool for environmental monitoring of lipophilic compounds. Concentrations should be expressed on the basis of (total) extractable lipids.The organisms to be compared should be sampled at a time when they have a similar physiological condition. This does not automatically mean synoptic sampling.Multi-component mixtures, such as PCB's, should be monitored on the basis of (selected) individual components in order to account for differences in behaviour of each component between different environmental compartments and animal species.Some representatives of the compounds discussed are strong inducers of mixed function oxygenase (MFO) enzyme systems. Therefore it should be investigated, if monitoring of MFO activity in addition to concentrations can be regarded as an early warning system of additive effects.  相似文献   

5.
分析华北11城市(北京、石家庄、太原、天津、大同、唐山、保定、呼和浩特、济南、郑州和西安)近年的天气型演变和PM10日均值随时空变化情况,发现华北城市群存在区域性的同步污染特征,各城市的环境过程和环境质量受这种区域性的背景影响显著。11城市的污染资料主分量分析结果可以很好地描述华北地区的各类天气型控制下,华北城市群区域性的同步污染和输送汇聚环境过程,并可以依据主分量分析结果对各城市的环境质量做出客观上的评价。  相似文献   

6.
The analytical techniques used for the determination of butyltin compounds in biological tissues are generally based on a succession of steps (e.g., extraction, derivatization, separation, detection) which are all prone to systematic errors. An interlaboratory programme performed at the EU level and based on a stepwise approach has enabled one to identify and remove most of these errors and to improve considerably the state of the art so that certification of a mussel reference material has been made possible. This paper describes the preparation of this mussel reference material containing monobutyltin (MBT), dibutyltin (DBT) and tributyltin (TBT), the homogeneity and stability studies and the analytical work performed for the certification of the contents of MBT [Sn(C4H9)3+], DBT [Sn(C4H9)2(2+)] and TBT [Sn(C4H9)3+]. The results obtained by a group of expert EU laboratories are discussed along with the methods used to certify the mass fractions (based on dry mass) of monobutyltin (1.50 +/- 0.28 mg kg-1 as MBT cations), dibutyltin (1.54 +/- 0.12 mg kg-1 as DBT cations) and tributyltin (2.20 +/- 0.19 mg kg-1 as TBT cations). The paper also describes an attempt to certify the content of triphenyltin in this material which, although reasonable agreement was found among the participants' results, failed owing to the instability of this compound. This new material will be of great support to ensure the quality control of butyltin determination in shellfish, as carried out in environmental monitoring programmes.  相似文献   

7.
人工神经网络在水环境质量评价中的应用   总被引:7,自引:0,他引:7  
为了将人工神经网络应用于水环境质量评价,应用了人工神经网络B—P算法,构造了水环境质量评价模型,该模型应用于实例评价结果表明,人工神经网络用于环境质量评价具有客观性,通用性和实用性。  相似文献   

8.
Examples are presented of different techniques which are in use, or could be used, to monitor the fate and effects of oil pollution in Dutch marine waters by oil spills and chronic contamination by rivers, processing water from the oil industry, etc.A number of techniques are presented to quantify the fate of oil in water, sediments and biota, and some readily available methods to monitor possible effects in the ecosystem.In Dutch coastal waters much effort is being given to airborne detection of oil at the sea surface in order to reduce pollution and to take rapid measures in cases of severe pollution. Oil concentrations in sediments and selected organisms can be monitored as a general quality control measure, and to check the functioning of licensed installations. If concentrations above background levels are found, research on possible effects should be initiated. In this context short term studies on stress-indicators are very useful. Laboratory based investigations, for example in model ecosystems, can be carried out to test hypotheses from such studies. Elevated oil concentrations and indications for ecological effects may result in changes in the management of the marine area in question. Monitoring of population dynamics and species composition, notably of benthic macrofauna, should be carried out to verify long-term effects on the ecosystem.  相似文献   

9.
The MAREL Iroise data buoy provides physico-chemical measurements acquired in surface marine water in continuous and autonomous mode. The water is pumped 1.5 m from below the surface through a sampling pipe and flows through the measuring cell located in the floating structure. Technological innovations implemented inside the measuring cell atop the buoy allow a continuous cleaning of the sensor, while injection of chloride ions into the circuit prevents biological fouling. Specific sensors for temperature, salinity, oxygen and fluorescence investigated in this paper have been evaluated to guarantee measurement precision over a 3 month period. A bi-directional link under Internet TCP-IP protocols is used for data, alarms and remote-control transmissions with the land-based data centre. Herein, we present a 29 month record for 4 parameters measured using a MAREL buoy moored in a coastal environment (Iroise Sea, Brest, France). The accuracy of the data provided by the buoy is assessed by comparison with measurements of sea water weekly sampled at the same site as part of SOMLIT (Service d'Observation du Milieu LIToral), the French network for monitoring of the coastal environment. Some particular events (impact of intensive fresh water discharges, dynamics of a fast phytoplankton bloom) are also presented, demonstrating the worth of monitoring a highly variable environment with a high frequency continuous reliable system.  相似文献   

10.
An algorithm for stepwise approximation to the most reliable source of contamination is proposed. The concept of the algorithm is based on discrimination rather than on similarity. Gradually, by means of more complicated and higher distinguishing power approaches, the differences between the spilled sample and the suspected source are checked. Capillary gas chromatography with flame-ionization and mass spectrometric detection was applied to gather the necessary data. Fingerprint, diagnostic parameter approaches and pattern recognition methods were used for reliably distinguishing the analytical results. If the compared samples are not discriminated by any means, they are considered as identical.  相似文献   

11.
Quantitative analyses of recent benthic foraminiferal assemblages (living and dead) were carried out on the surface sediments of Sulaibikhat Bay. Marked contrast in foraminiferal assemblages between the shallow tidal mudflats and the deep tidal channel and their relation to the extent of pollution were observed. Cluster analysis of quantitative data on the distribution of foraminiferal tests revealed three assemblages that depend mainly on the intensity of pollution; (1) a highly polluted tidal flat assemblage, (2) normal (or less polluted) mud flat assemblage and, (3) tidal channel and subtidal assemblage. The highly polluted assemblage characterized by a drop in species densities (< 100 tests/20 cm(3) sediment) but with high average diversity (5.8 Yule-Simpson Index). The microfauna of the less polluted flat displays relatively lower diversity (4.6) but high density of tests (47.2% of the total picked tests). The most abundant species of this assemblage is Ammonia tepida, displays its maximum density in this assemblage. Ammonia tepida drops in density from 17.12% to 3.07% in the polluted assemblage. Tidal channel foraminiferal assemblages should normally display lower diversities than those of tidal flats, because tidal current in the channels tend to wash away most nutrient materials. However, this is not the case of the present study area which could be due to environmental setting of the Sulaibikhat Bay in which tidal currents bring in exceptionally high amounts of nutrients from Shatt Al-Arab Estuary and in which the tidal flats are strongly and adversely polluted.  相似文献   

12.
13.
1997年6月5日,大连市成为全国首批在新闻媒体中发布城市空气质量周报的城市之一,1998年5月15日又在全国率先发布城市空气质量日报.文章以空气质量周(日)报的发布为切入点,全面论述其良好的社会效益、明显的环境效益及潜在的经济效益.根据环境质量的消费性,结合大连的实际,提出环境信息网络是建立面向公众的环境信息体系最便捷的途径.  相似文献   

14.
在简述了农业环境监测重要性的基础上,介绍了呼兰县农业生态环境水质监测的方案,并对监测结果进行了分析。评价了呼兰县农业生态环境水质情况。  相似文献   

15.
地表水环境质量定性评价   总被引:7,自引:1,他引:7  
针对目前缺乏统一的地表水环境质量定性评价准则的现状,根据我国主要水体的污染程度,提出了断面、河流、水系水质定性评价方法。  相似文献   

16.
大气环境质量模糊评价的可视化实现   总被引:2,自引:0,他引:2  
以模糊聚类法为算法基础,运用计算机可视化技术,进行大气环境质量评价初步探索。计算机技术在环境评价中的应用,可以方便数据处理和资源共享。选用武汉市大气环境监测资料,应用该方法评价和分析武汉市大气环境质量,取得了令人满意的结果。  相似文献   

17.
18.
Numerical models are often used to evaluate the potential impact of human alternation of natural water bodies and to help the design of the alternation to mitigate its impacts. In the past decade, three-dimensional hydrodynamic and reactive transport modeling has matured from a research subject to a practical analysis technology. This paper presents a practical study in which a three-dimensional hydrodynamic and water quality model [hydrodynamic eutrophication model (HEM-3D)] was applied to determine the optimal location for treated wastewater discharged from marine outfall system in the Keelung harbor and the adjacent coastal sea. First, model validation was conducted with respect to surface elevation, current, and water quality variables measured in the Keelung harbor station and its coastal sea. The overall performance of the model was in qualitative agreement with the available field data. The model was then used to evaluate several scenarios of the locations from marine outfall system. Based on model simulation results, a location at the northeast of Ho-Ping Island was recommended for adoption because the environmental impact is smaller than any other alternative.
Wen-Cheng LiuEmail:
  相似文献   

19.
The evaluation of sustainable tourism strategies promoted by National Parks (NP) related stakeholders is a key concern for NP managers. To help them in their strategic evaluation procedures, in this paper we propose a methodology based on the Analytic Network Process and a Delphi-type judgment-ensuring procedure. The approach aims at involving stakeholders in a participatory and consensus-building process.The methodology was applied to Los Roques NP in Venezuela. The problem included three sustainable tourism strategies defined by the stakeholders: eco-efficient resorts, eco-friendly leisure activities and ecological transportation systems. Representatives of eight stakeholders participated in the methodology. 13 sustainability criteria were selected.Results provide some important insights into the overall philosophy and underlying participants' conception of what sustainable development of Los Roques NP means. This conception is broadly shared by stakeholders as they coincided in the weights of most of the criteria, which were assigned individually through the questionnaire. It is particularly noteworthy that tourists and environmentalists almost fully match in their assessments of criteria but not of the alternatives.Moreover, there is a great agreement in the final assessment. This suggests that the regular contact among the different stakeholders, i.e. tourists with inhabitants, authorities with environmentalists, tour operators with representatives of the ministry, etc. has led to a common understanding of the opportunities and threats for the NP.They all agreed that the procedure enhances participation and transparency and it is a necessary source of information and support for their decisions.  相似文献   

20.
Organochlorine pesticides (OCPs) in sediment, water and biota samples from the coastal marine environment of Mumbai were analysed to elucidate their distribution in various environmental compartments. HCH isomers, dichlorodiphenyltrichloroethane (DDT) and its metabolites were the predominantly identified compounds in all the samples. High ratios of DDT to dichlorodiphenyldichloroethylene (DDE) were found in seawater samples. This indicates the presence of a significant source of DDT in this region. In sediment samples, the gamma-isomer contributed almost 55% to the total HCH, indicating a high affinity of the gamma-isomer towards the sediment. The levels of organochlorines in fish obtained from this region were found to be lower than the levels of organochlorines in fish in temperate regions.  相似文献   

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