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1.
综述了美国核电厂辐射环境监测管理体系和环境信息公开制度及法制化管理模式,对比分析了我国辐射环境监测与信息发布实际开展情况及存在问题,提出需借鉴美国核管理委员会(NRC,以下简称NRC)的管理经验,进一步完善我国辐射环境监测标准体系,建立辐射环境监测数据公开制度,加强公众参与制度建设,明确核电厂辐射环境监测管理边界等建议。  相似文献   

2.
Two different approaches to modeling the environmental fate of organic chemicals have been developed in recent years. The first approach is applied in multimedia box models, calculating average concentrations in homogeneous boxes which represent the different environmental media, based on intermedia partitioning, transport, and degradation processes. In the second approach, used in atmospheric transport models, the spatially and temporally variable atmospheric dynamics form the basis for calculating the environmental distribution of chemicals, from which also exchange processes to other environmental media are modeled. The main goal of the present study was to investigate if the multimedia mass balance models CliMoChem, SimpleBox, EVn-BETR, G-CIEMS, OECD Tool and the atmospheric transport models MSCE-POP and ADEPT predict the same rankings of the overall persistence (P(ov)) and long-range transport potential (LRTP) of POPs, and to explain differences and similarities between the rankings by the mass distributions and inter-compartment mass flows. The study was performed for a group of 14 reference chemicals. For P(ov), the models yield consistent results, owing to the large influence of phase partitioning parameters and degradation rate constants, which are used similarly by all models. Concerning LRTP, there are larger differences between the models than for P(ov), due to different LRTP calculation methods and spatial model resolutions. Between atmospheric transport models and multimedia fate models, no large differences in mass distributions and inter-compartment flows can be recognized. Deviations in mass flows are mainly caused by the geometrical design of the models.  相似文献   

3.
The Canadian Arctic is undergoing considerable social and environmental change. Anthropogenic stressors on this sensitive environment include climate change, contaminants, resource extraction, tourism and increasing human populations. The Northern Ecosystem Initiative (NEI) is a program aimed at supporting the sustainability of northern communities, and at improving our understanding of how northern ecosystems respond to these environmental stressors. A key element of the NEI is to establish partnerships between all levels of government, non-governmental environmental agencies, and northern residents. The NEI is an important source of financial support critical for social and environmental scientists as well as northern residents and their community and regional organizations. Initiated in 1998, the NEI has supported numerous northern scientific and capacity-building projects, and has evaluated the information gained from this work to refine and focus its future support to address key information gaps and northern needs.  相似文献   

4.
The combined effects of human activities and natural variability present significant challenges to the goals of protecting, restoring, and sustaining coastal ecosystems. Meeting these challenges and resolving conflicts in an informed fashion will require: (1) more timely detection and prediction of environmental changes and their consequences; and (2) more timely access to relevant environmental information. The achievement of these goals depends on the development of a sustained and integrated coastal ocean observing system (ICOOS) that insures timely access to the data and information required to improve: (1) climate predictions and the effects of changes in the weather on coastal populations; (2) efforts to sustain and restore healthy coastal marine ecosystems and living marine resources; and (3) compliance monitoring and evaluations of the efficacy of environmental policies. Although the responsible federal and state agencies all require similar environmental information, many separate programs have evolved for collecting, managing, and analyzing data for various purposes. Consequently, there is too much redundancy; access to diverse data from disparate sources is limited and time consuming; and individual programs are inevitably underfunded and too limited in scope. A system is needed that coordinates and integrates many of the elements of these programs to minimize redundancy, be more comprehensive, provide more timely access to data and information, and satisfy the information needs of a greater number of user groups in a more cost-effective fashion. This is the purpose of the ICOOS.  相似文献   

5.
Pentachlorophenol (PCP) has been used as a herbicide, biocide and preservative worldwide since the 1930s and as a result, extensive and prolonged contamination exists. The environmental impact increases when its many degradation products are taken into consideration. A number of chloroanisols and their related chlorophenols have been found in cork slabs collected from Portuguese oak tree forests before stopper manufacturing, and contamination by PCP and polychlorinated anisole (PCA) has been detected in Canadian forests. It is suggested that the use of polychlorinated phenols, in particular PCP, is thought to be a cause of the cork taint problem in wine, a major socio-economic impact not only for industry but on sensitive and highly biodiverse ecosystems. It also highlights particular issues relating to the regional regulation of potentially toxic chemicals and global economics world wide. To fully understand the impact of contamination sources, the mechanisms responsible for the fate and transport of PCP and its degradation products and assessment of their environmental behaviour is required. This review looks at the current state of knowledge of soil sorption, fate and bioavailability and identifies the challenges of degradation product identification and the contradictory evidence from field and laboratory observations. The need for a systematic evaluation of PCP contamination in relation to cork forest ecosystems and transfer of PCP between trophic levels is emphasised by discrepancies in bioaccumulation and toxicity. This is essential to enable long term management of not only transboundary contaminants, but also the sustainable management of socially and economically important forest ecosystems.  相似文献   

6.
Rapid development and application of nanomaterials and nanotechnology make assessment of their potential health and environmental impacts on humans, non-human biota, and ecosystems imperative. Here we show that pumpkin plants (Cucurbita maxima), grown in an aqueous medium containing magnetite (Fe3O4) nanoparticles, can absorb, translocate, and accumulate the particles in the plant tissues. These results suggest that plants, as an important component of the environmental and ecological systems, need to be included when evaluating the overall fate, transport and exposure pathways of nanoparticles in the environment.  相似文献   

7.
Over 35 years of US and Canadian pollution prevention and control efforts have led to substantial improvements in environmental quality of the Detroit River and western Lake Erie. However, the available information also shows that much remains to be done. Improvements in environmental quality have resulted in significant ecological recovery, including increasing populations of bald eagles (Haliaeetus leucocephalus), peregrine falcons (Falco columbarius), lake sturgeon (Acipenser fulvescens), lake whitefish (Coregonus clupeaformis), walleye (Sander vitreus), and burrowing mayflies (Hexagenia spp.). Although this recovery is remarkable, many challenges remain, including population growth, transportation expansion, and land use changes; nonpoint source pollution; toxic substances contamination; habitat loss and degradation; introduction of exotic species; and greenhouse gases and global warming. Research/monitoring must be sustained for effective management. Priority research and monitoring needs include: demonstrating and quantifying cause-effect relationships; establishing quantitative endpoints and desired future states; determining cumulative impacts and how indicators relate; improving modeling and prediction; prioritizing geographic areas for protection and restoration; and fostering long-term monitoring for adaptive management. Key management agencies, universities, and environmental and conservation organizations should pool resources and undertake comprehensive and integrative assessments of the health of the Detroit River and western Lake Erie at least every 5 years to practice adaptive management for long-term sustainability.  相似文献   

8.
9.
Regional monitoring and assessments of the health of forested ecosystems require indicators of forest conditions and environmental stresses. Indicator selections depend on objectives and the strategy for data collection and analysis. This paper recommends a set of indicators to signal changes in forest ecosystem distribution, productivity, and disturbance. Additional measurements are recommended to help ascribe those changes to climate variation, atmospheric deposition, and land use patterns. The rationale for these indicators is discussed in the context of a sequential monitoring and assessment strategy.  相似文献   

10.
The occurrence and fate of polyfluoroalkyl compounds (PFCs) in the aquatic environment has been recognized as one of the emerging issues in environmental chemistry. PFCs comprise a diverse group of chemicals that are widely used as processing additives during fluoropolymer production and as surfactants in consumer applications for over 50 years. PFCs are known to be persistent, bioaccumulative and have possible adverse effects on humans and wildlife. As a result, perfluorooctane sulfonate (PFOS) has been added to the persistent organic pollutants (POPs) list of the Stockholm Convention in May 2009. However, their homologues, neutral precursor compounds and new PFCs classes continue to be produced. In general, several PFCs from different classes have been detected ubiquitously in the aqueous environment while the concentrations usually range between pg and ng per litre for individual compounds. Sources of PFCs into the aqueous environment are both point sources (e.g., wastewater treatment plant effluents) and nonpoint sources (e.g., surface runoff). The detected congener composition in environmental samples depends on their physicochemical characteristics and may provide information to their sources and transport pathways. However, the dominant transport pathways of individual PFCs to remote regions have not been conclusively characterised to date. The objective of this article is to give an overview on existing knowledge of the occurrence, fate and processes of PFCs in the aquatic environment. Finally, this article identifies knowledge gaps, presents conclusions and recommendations for future work.  相似文献   

11.
The atmosphere is an important pathway to be considered in assessment of the environmental impact of radioactivity releases from nuclear facilities. The estimation of concentration of released effluents in air and possible ground contamination needs an understanding of relevant atmospheric dispersion. This paper describes the meteorological characteristics of Narora Atomic Power Station (NAPS) Nuclear Power Project site by using the integral parameters developed by Allwine and Whiteman (Atmospheric Environment 28(4):713–721, 1994). Meteorological data measured during the period 2006–2010 were analysed. The integral quantities related to the occurrence of stagnation, recirculation and ventilation characteristics were studied for the NAPS site to assess the dilution potential of the atmosphere. Wind run and recirculation factors were calculated for a 24-h transport time using 5 years of hourly surface measurements of wind speed and direction. The occurrence of stagnation, recirculation and ventilation characteristics during 2006–2010 at the NAPS site is observed to be 33.8, 19.5 and 34.7 % of the time, respectively. The presence of strong winds with predominant wind direction NW and WNW during winter and summer seasons leads to higher ventilation (48.1 and 44.3 %) and recirculation (32.6 % of the summer season). The presence of more dispersed light winds during pre-winter season with predominant wind directions W and WNW results in more stagnation (59.7 % of the pre-winter season). Thus, this study will serve as an essential meteorological tool to understand the transport mechanism of atmospheric radioactive effluent release from any nuclear industry during the pre-operational as well as operational phase.  相似文献   

12.
A first medium term monitoring of atmospheric transport and distribution for persistent organic pollutants (POPs) in Bj?rn?ya (Bear island) air samples has been performed in the period between week 51/1999 and week 28/2003. A total of 50 single compounds consisting of polychlorinated biphenyls (33 congeners), hexachlorobenzene (HCB), hexachlorocyclohexane isomers (alpha-, beta-, gamma-HCH), alpha-endosulfan, cyclodiene pesticides (chlordanes, nonachlor-isomers, oxy-chlordane, heptachlor and chlordane) as well as dichlorodiphenyltrichloroethane (DDT) derivatives were analysed and quantified. Atmospheric transport of POPs was identified as an important contamination source for the island. PCBs, HCB and HCH isomers were the predominant POP groups, contributing with 70-90% to the overall POP burden quantified in the Bj?rn?ya air samples. The highest concentration levels for a single compound were found for HCB (25-35 pg m(-3)). However, the sum of 33 PCB congeners was found to be in the same concentration range (annual means between 15 and 30 pg m(-3)). Cyclodiene pesticides, DDT derivatives and alpha-endosulfan were identified as minor contaminants. Several atmospheric long-range transport episodes were identified and characterised. Indications for industrial emissions as well as agricultural sources were found for the respective atmospheric transport episodes. A first simple statistical correlation assessment showed that for long-range transport of pollution, the local meteorological situation is not as important as the air mass properties integrated over the time period of the transport event. The local weather situation, on the other hand, is important when investigating deposition rates and up-take/accumulation properties in the local ecosystem. Based upon chemical data interpretation, valuable information about the influence of primary and secondary sources on the air mass contamination with chlorinated insecticides (e.g., HCHs) was found and discussed. The interdisciplinary interpretation of contaminant data using statistical methods, chemical analysis, meteorological modelling and classical meteorological information for a comprehensive evaluation of atmospheric long range transport into the European Arctic (Bj?rn?ya) has proven to be a highly versatile tool not only for atmospheric scientists but also with strong potential for regulatory purposes.  相似文献   

13.
A pilot study is presented evaluating selected chlorinated pesticides as chemical tracers for water masses in a sub-Arctic fjord system (Godth?bsfjord, western Greenland). Polyoxymethylene (POM) based passive water samplers were deployed during summer-autumn 2010. The levels of the analysed chlorinated pesticides in the fjord surface waters were found to be low compared to earlier studies. α-Hexachlorocyclohexane (α-HCH) and hexachlorobenzene (HCB) were the predominant contaminants. However, these two compounds have higher levels in oceanic water compared to freshwater influenced fjord waters. These chemicals can thus be considered as indicators for direct atmospheric long-range transport, while the organochlorine pesticides like trans-, cis-chlordane, trans-nonachlor and oxychlordane that are detected in the inner parts of the fjord are indicators for potential freshwater sources such as rivers and glacial meltwater runoff (secondary sources). The average values were 50 pg L(-1) for HCB and 11 pg L(-1) for α-HCH. These concentrations are comparable to levels in fjords in Svalbard (Norwegian Arctic), but lower than in open and/or ice covered oceans in the Canadian Arctic. Two air samplers were deployed for the identification of direct atmospheric contributions. Local contamination sources do not contribute significantly. The study demonstrated the value of passive water sampling devices for comprehensive hydrological characterization of Arctic coastal waters.  相似文献   

14.
A probabilistic analysis of atmospheric transport and deposition patterns from two nuclear risk sites-Kamchatka and Vladivostok-situated in the Russian Far East to countries and geographical regions of interest (Japan, China, North and South Koreas, territories of the Russian Far East, State of Alaska, and Aleutian Chain Islands, US) was performed. The main questions addressed were the following: Which geographical territories are at the highest risk from hypothetical releases at these sites? What are the probabilities for radionuclide atmospheric transport and deposition on different neighboring countries in case of accidents at the sites? For analysis, several research tools developed within the Arctic Risk Project were applied: (1) isentropic trajectory model to calculate a multiyear dataset of 5-day forward trajectories that originated over the site locations at various altitudes; (2) DERMA long-range transport model to simulate 5-day atmospheric transport, dispersion, and deposition of 137Cs for 1-day release (at the rate of 10(10) Bq/s); and (3) a set of statistical methods (including exploratory, cluster, and probability fields analyses) for evaluation of trajectory and dispersion modeling results. The possible impact (on annual, seasonal, and monthly basis) of selected risk sites on neighboring geographical regions is evaluated using a set of various indicators. For trajectory modeling, the indicators examined are: (1) atmospheric transport pathways, (2) airflow probability fields, (3) fast transport probability fields, (4) maximum possible impact zone, (5) maximum reaching distance, and (6) typical transport time fields. For dispersion modeling, the indicators examined are: (1) time integrated air concentration, (2) dry deposition, and (3) wet deposition. It was found for both sites that within the boundary layer the westerly flows are dominant throughout the year (more than 60% of the time), increasing with altitude of free troposphere up to 85% of the time. For the Kamchatka site, the US regions are at the highest risk with the average times of atmospheric transport ranging from 3 to 5.1 days and depositions of 10(-1) Bq/m2 and lower. For the Vladivostok site, the northern China and Japan regions are at the highest risk with the average times of atmospheric transport of 0.5 and 1.6 days, respectively, and depositions ranging from 10(0) to 10(+2) Bq/m2. The areas of maximum potentially impacted zones are 30 x 10(4) km2 and 25 x 10(4) km2 for the Kamchatka and Vladivostok sites, respectively.  相似文献   

15.
Concepts, planning and design procedures are examined that are needed in the development of long-term stream monitoring programs in forested regions. A long-term stream monitoring program is viewed as the key component for bringing together management organizations, researchers and decision-makers to improve the management of natural resources. The keystones of such ecosystem monitoring are long-term data records that provide the basis for analysis of environmental assessment objectives, predictions and analysis of outcomes which in-turn can be used to modify and improve future projects. Management organizations that initiate long-term monitoring programs are urged to use monitoring actions and information to facilitate decision-making processes that pertain to conserving and allocating resources for future beneficial uses. Recommendations are provided for careful planning and definition of interactive activities of monitoring programs and that should provide information feedbacks that can be used to evaluate issues pertaining to beneficial uses of resources. Procedural requirements and literature sources are suggested for developing long-term stream monitoring programs. They include reviews of background and historical information to provide precise definitions of long-term objectives, planning considerations and monitoring methods. Examples are given of specific procedures that need to be identified during the planning process. They include the application of management standards to variable conditions encountered within natural ecosystems and the detection of the timing of recovery phases of stream ecosystem development following a disturbance. These procedures are viewed as being essential for improving applications of management standards and perceived thresholds to stream and watershed ecosystems monitoring programs.  相似文献   

16.
大气降尘量是重要的环境指标之一,可以较客观地反映和评价城市局部地区扬尘污染水平,对评价城市区域环境空气质量、分析大气污染来源和变化具有重要意义。国内外大气降尘监测普遍采用传统的手工监测方法,手工法因时效性差、效率低、能耗大、质控难、误差大等原因已不适应现代环境管理的需求。随着科技与网络的发展,自动监测方法成为发展趋势。文章主要阐述了上海市降尘自动监测技术的研发过程及实际应用,介绍了自主研发的降尘自动监测仪的原理、关键技术和系统组成。通过粉尘舱内实验、降尘自动监测方法与手工重量法比对测试及为期一年的试点应用,分析了降尘自动监测方法的精密度、准确度、相对误差及适用性,并探讨了降尘自动监测的应用前景。  相似文献   

17.
Forests make up large ecosystems and can play an important role in mitigating the emissions of CO2, the most important greenhouse gas. However, they are sources of atmospheric carbon when they are disturbed by human or natural causes. Storage of carbon through expansion and adaptive management of forest ecosystems can assist in reducing carbon concentrations in atmosphere. This study proposes a methodology to produce spatially explicit estimates of the carbon storages (aboveground plus belowground) depending on land use/cover changes in two different forest ecosystems during various periods. Carbon storages for each forest ecosystem were projected according to inventory data, and carbon storages were mapped in a geographic information system (GIS). Results showed that total carbon stored in above and belowground of both forest ecosystems increased from one period to other because of especially increase of productive forest areas and decline of degraded forest areas as well as protection of spruce forests subject to insect attacks.  相似文献   

18.
Pharmaceuticals and personal care products (PPCPs) represent pollutants of emerging concern, originating in surface and drinking waters largely from their persistence in wastewater effluent. Accordingly, a wealth of recent investigations has examined PPCP fate during wastewater treatment, focusing on their removal during conventional (e.g., activated sludge) and advanced (e.g., ozonation and membrane filtration) treatment processes. Here, we compile nearly 1500 data points from over 40 published sources pertaining to influent and effluent PPCP concentrations measured at pilot- and full-scale wastewater treatment facilities to identify the most effective series of technologies for minimizing effluent PPCP levels. Available data suggest that at best a 1-log(10) concentration unit (90%) of PPCP removal can be achieved at plants employing only primary and secondary treatment, a performance trend that is maintained over the range of reported PPCP influent concentrations (ca. 0.1-10(5) ng L(-1)). Relatively few compounds (15 of 140 PPCPs considered) are consistently removed beyond this threshold at facilities using solids removal and conventional activated sludge (CAS), and most PPCPs are removed to a far lesser extent. Further, increases in CAS hydraulic retention time or sludge retention time do not appreciably increase removal beyond this limit. In contrast, plants employing advanced treatment methodologies, particularly ozonation and/or membranes, remove the vast majority of PPCPs beyond 1-log(10) concentration unit and oftentimes to levels below analytical detection limits in effluent. Data also indicate that passive approaches for tertiary treatment (e.g., wetlands and lagoons) represent promising options for PPCP removal. We conclude by addressing future challenges and frontiers in wastewater management posed by PPCPs including analytical needs for their real-time measurement, energy demands associated with advanced treatment technologies, and byproducts arising from transformation of PPCPs during treatment.  相似文献   

19.
Chemical monitoring of aquatic ecosystems describes the chemical exposures of aquatic biota and measures the success of pollution control. However, meeting water quality criteria cannot assure that aquatic biota are protected from the effects of unexpected chemicals, mixtures and interactions between toxicity and environmental stressors.Biological monitoring is an obvious solution since aquatic biota integrate spatial and temporal variations in exposure to many simultaneous stressors. Top predators, typical of specific ecosystems (e.g. lake trout in cold water oligotrophic lakes) indicate whether environmental criteria have been met. The presence of naturally reproducing, self-sustaining and productive stocks of edible fish demonstrates a high quality environment. If these conditions are not met, there is a clear sign of environmental degradation. Specific changes in population structure and performance may also diagnose which life stage is affected and the nature of the stressor.Unfortunately, environmental managers cannot rely solely on populations, communities or ecosystems to indicate chmical effects. The lag between identifying a problem and finding a cause may destroy the resource that we wish to protect, particularly where chemicals are persistent.A solution to this dilemma is the measurement of primary or secondary responses of individual organisms to chemical exposure. Since toxicity at any level of organization must start with a reaction between a chemical and a biological substrate, these responses are the most sensitive and earliest sign of chemical exposure and effect.Application of this idea requires research on molecular mechanisms of chemical toxicity in aquatic biota and adaptation of existing mammalian diagnostic tools. Since relevance of biochemical responses to populations and ecosystems is not obvious, there is a need to study the links between chemical exposure and responses of individuals, populations and ecosystems.The recognition of chemical problems and cause-effect relationships requires the integration of chemical and biological monitoring, using the principles of epidemiology to test the strength of relationships and to identify specific research needs. The contamination of a reservoir with selenium and impacts on fish populations provide an excellent example of this approach.  相似文献   

20.
A potentially important exposure route for humans is the ingestion of chemicals via drinking water. If comprehensive exposure assessments are to be completed for either existing or proposed new chemicals and cost effective control strategies developed, then a quantitative understanding of multimedia transport and fate of specific chemical pollutants must be achieved. Mathematical models provide a powerful framework into which quantitative relationships may be placed to provide guidance in reaching water quality goals. Existing, state-of-the-art media-specific toxic organic transport and fate models for atmospheric (DiDOT), land surface (NPS) and surface water processes (EXAMS) and potable water treatment (WTP) have been linked to demonstrate the technical feasibility of such an approach. Limited application and sensitivity testing of this linked modeling system has shown that the impact of various source loadings and control strategies on drinking water quality can be estimated.  相似文献   

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