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1.
This paper summarizes information on the spatial and temporal variability of selected air toxics pollutants collected on a national basis primarily for a period encompassing 1990-2003. Spatial information on pollutant concentrations is characterized in terms of within-city and between-city variability. Temporal information is summarized as diurnal and seasonal variability and in multiyear trends. The information on variability is presented in the framework of a larger need for systematic documentation of information on air toxics pollutants to assess progress in air pollution control programs.  相似文献   

2.
Abstract

This paper summarizes information on the spatial and temporal variability of selected air toxics pollutants collected on a national basis primarily for a period encompassing 1990–2003. Spatial information on pollutant concentrations is characterized in terms of within-city and between-city variability. Temporal information is summarized as diurnal and seasonal variability and in multiyear trends. The information on variability is presented in the framework of a larger need for systematic documentation of information on air toxics pollutants to assess progress in air pollution control programs.  相似文献   

3.
放射源管理系统是一种基于环境地理信息系统平台的资源管理系统,是GIS技术与环境监测技术、环境管理技术、数据库技术等各种环境信息分析和处理技术的集成。系统为环保部门提供了一个功能强大的空间信息服务和管理工具,可以直观、方便地获取放射源的监控、管理等数据信息,为环境管理部门的决策提供依据。  相似文献   

4.
The investigation of contaminated sites is usually a long and expensive process. It is therefore desirable to use a combination of methodologies in an integrative approach that can reduce redundant information gathering. The objective of this study was to examine the usefulness of 2 non-intrusive exploration techniques in a contaminated site investigation. Borehole positioning based on geophysical measurements was compared to positioning based on the Bayesian expert system for flow-field modeling. The goal set at the field site was the assessment of the type and load of contaminants transported from the landfill site to the adjacent aquifer and the extent of leachate plumes within the groundwater. The two methods made different demands on information gathering and were found to be complementary. The geophysical approach focused attention on the waste compartments at the site and on mixing plumes in the adjacent aquifer but could not, without prior information, provided information on the flow field. The Bayesian approach to flow-field modeling determined areas of greatest model uncertainty at the model boundaries. The model highlighted areas of greatest uncertainty that might otherwise have been overlooked and provided information on the most likely mean direction of the leachate plumes. It was concluded that both methods contribute to a site investigation and should be used before additional drilling is carried out.  相似文献   

5.
Löe J  Röskaft E 《Ambio》2004,33(6):283-288
Attacks by large carnivores on humans can occasionally help to generate significant resistance to carnivore conservation efforts. We have reviewed research addressing concerns for human safety in large carnivore conservation, and have evaluated statements about the frequencies and causes of attacks based on our findings concerning i) existing data on the number of attacks by large carnivores in various parts of the world; ii) information systems documenting details of attacks; and iii) research that provides credible advice on what to do when encountering a large carnivore, to minimize the likelihood of being attacked. We conclude that little information exists for any of these criteria and what is available is often inadequate to determine the frequency of attacks, their causes and how to avoid them. We suggest that information systems, including database(s) on attacks and encounters, should be established for large carnivore conservation efforts, to supply information and to answer future requests for this information.  相似文献   

6.
M Younes 《Chemosphere》1999,39(8):1253-1257
Specific issues in health risk assessment of EDCs and correlated international activities thereof are discussed. Risk characterization is a synthesis of all information including hazard assessment, dose-response relationship, and exposure information to identify clearly the strengths and weaknesses of the database, the criteria applied to evaluation and validation of all aspects of methodology, and the conclusions reached from the review of scientific information. In the case of EDCs, new models need to be developed taking into account possible new kinds of information, e.g., effects of EDCs on gene activation in response to hormonal challenge or effects on receptor expression. Such models should also account for homeostatic adaptive responses and consider the possibility of having windows of exposure for given effects. Work to compile and harmonize the definitions and terms appropriate to endocrine disruption will be conducted within the joint IPCS/OECD project on harmonization of risk/hazard assessment terminology reviews. The ICPS is the process of preparing a "State of the Science" report, and is implementing a global inventory of ongoing research on ECDs.  相似文献   

7.
This report summarizes information and results presented at the 2nd Conference on Fabric Filter Technology for Coal-Fired Power Plants. Sponsored by the Air Quality Control Program, Coal Combustion Systems Division, of the Electric Power Research Institute, in cooperation with the Public Service Company of Colorado, the conference focused on recent technological developments in the design and operation of fabric filters (baghouses) in utility settings. The information presented was designed to assist utilities currently operating baghouses, preparing engineering specifications for new units, or contemplating installation of baghouses for the first time.  相似文献   

8.

Recent calculations of carbon dioxide (CO2) emissions have faced challenges because data consist of only partial information, which is called “incomplete information.” According to the emission factor method, energy consumption and CO2 emission factors with incomplete information may lead to unmatched multiplication between themselves, which affects accuracy and increases uncertainties in emission results. To address a specific case of incomplete information that has not been fully explored, we studied the effects of incomplete condition information on the estimates of CO2 emissions from liquefied natural gas (LNG) in China. Based on Chinese LNG sampling data, we obtained the specific-country CO2 emission factor for LNG in China and calculated the corresponding CO2 emissions. By applying hypothesis testing, regression analysis, variance analysis, or Monte Carlo (MC) simulations, the effects of incomplete information on the uncertainty of CO2 emission calculations in three cases were analyzed. The results indicate that calorific values have more than a 9.8% impact on CO2 emission factors and CO2 emissions with incomplete sample information. Regarding incomplete statistical information, the impact of statistical temperature on CO2 emissions exceeds 5.5%. Regarding incomplete sample and statistical information, sample and statistical temperatures can individually increase estimate biases by more than 5.2%. Significantly, the impacts of sample temperature and statistical temperature may offset each other. Therefore, the incomplete condition information is quite important and cannot be ignored in the estimation of CO2 emissions from LNG and international fair comparison.

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9.
以引江济巢工程为对象,在充分搜集巢湖流域水环境信息的基础上,利用Visual Basic6.0结合MapObjects2.0开发基于地理信息系统(GIS)的引江济巢数值模拟系统,实现对引江济巢工程基础地理信息、水文信息、水质信息等的统计、分析与管理。并通过嵌入式集成方法实现数学模型与GIS的紧密集成,实现了在污染因素由用户自行设定下进行"所见即所得"的动态仿真能力,为引江济巢调水方案的论证和调水过程中的环境管理提供技术支撑。  相似文献   

10.
Gipperth L  Elmgren R 《Ambio》2005,34(2):157-162
The implementation of the EU Water Framework Directive and the achievement of its water quality objectives will to a large degree depend on scientific knowledge about the sources and status of water resources and the effects of mitigative measures. Coastal waters will be of central interest, since the management of whole river basins may be affected if coastal water status is not satisfactory. The Water Directive's general directions on what information the water authorities need and on suitable methods for obtaining such information leave it to the Member states to decide on more precise instructions. Improved legal mechanisms are needed to assist and guide the managers and scientists charged with implementing the directive and achieving its water quality objectives, particularly when faced with insufficient information, flawed knowledge, or changed circumstances. We assess progress in the current process of implementing the Water Directive in Sweden, focussing on coastal waters, and on general problems arising using this type of legal technique.  相似文献   

11.
Generalized additive models were used to analyze the time series of daily hospital admissions for cardiovascular and cerebrovascular diseases over the period of 1987-1995 in three major metropolitan areas--Cook County, IL; Los Angeles County, CA; and Maricopa County, AZ--in the United States. In Cook and Maricopa Counties, admissions information was only available for the elderly (ages 65 and over), while in Los Angeles County, admissions information was available for all ages. In Cook County, daily monitoring information was available on PM10, CO, SO2, NO2, and O3. In Los Angeles and Maricopa Counties, monitoring information was available daily on the gases, and information on PM10 was available every sixth day. In Los Angeles County, information on PM2.5 was also available every sixth day. In Cook and Los Angeles Counties, associations were found between each pollutant, with the exception of O3, and admissions for cardiovascular disease, with the gases showing the strongest associations. In two-pollutant models with PM and one of the gases, the effect of the gases remained stable, while the effect of PM became unstable and insignificant. In Maricopa County, the gases, with the exception of O3, were weakly associated with hospital admissions for cardiovascular disease, while PM was not. In two-pollutant models with two of CO, SO2, and NO2, the pattern of results is heterogeneous in the three counties. In all three counties, only weak evidence of any association between air pollution and cerebrovascular admissions was found.  相似文献   

12.
上海市青浦区农业非点源污染的流域分配研究   总被引:1,自引:0,他引:1  
根据遥感技术得到的土地利用类型、河网、道路、圩区等信息,结合地理信息系统(GIS)的空间分析功能,建立了在多种空间因素影响下确定农业非点源污染负荷的流域分配方法。在此基础上,以上海市青浦区为例,得到了该区各河段中的污染负荷量.从而为寻求流域内合理的土地利用模式和农业非点源污染排放总量的控制方法提供决策依据。  相似文献   

13.
The United States Environmental Protection Agency (USEPA) has pursued the estimation of risk of adverse health effects from exposure to chemical mixtures since the early 1980s. Methods used to calculate risk estimates of mixtures were often based on single chemical information that required assumptions of dose-addition or response-addition and did not consider possible changes in response due to interaction effects among chemicals. Full factorial designs for laboratory studies can produce interactions information, but these are expensive to perform and may not provide the information needed to evaluate specific environmentally relevant mixtures. In this research, groups of Japanese medaka (Oryzias latipes) embryos were exposed to binary mixtures of benzene and toluene as well as to each of these chemicals alone. Endpoint specific dose-response models were built for the hydrocarbon mixture under an assumption of dose-additivity, using the single chemical dose-response information on benzene and toluene. The endpoints included heart rate, heart rate progression, and lethality. Results included a synergistic response for heart rate at 72 h of development, and either additivity or antagonism for all other endpoints at 96 h of development. This work uses an established statistical method to evaluate the toxicity of an environmentally relevant mixture to ascertain whether interaction effects are occurring, thus providing additional information on toxicity.  相似文献   

14.
The Swedish Regional Climate Modelling Programme, SWECLIM: a review   总被引:8,自引:0,他引:8  
The Swedish Regional Climate Modelling Programme, SWECLIM, was a 6.5-year national research network for regional climate modeling, regional climate change projections and hydrological impact assessment and information to a wide range of stakeholders. Most of the program activities focussed on the regional climate system of Northern Europe. This led to the establishment of an advanced, coupled atmosphere-ocean-hydrology regional climate model system, a suite of regional climate change projections and progress on relevant data and process studies. These were, in turn, used for information and educational purposes, as a starting point for impact analyses on different societal sectors and provided contributions also to international climate research.  相似文献   

15.
Relatively little prior use has been made of information theory in air quality analysis. This paper explores whether basic, but formal, quantitative measures of information content might yield fresh perspectives on seasonal variations in the ground-level ozone concentration field across the lower Fraser Valley (LFV), British Columbia, Canada. I calculate Shannon entropy in daily maximum ozone concentration on a month-by-month, station-by-station basis, using 1 year of hourly measurements from 18 air quality monitoring stations. The values are then qualitatively compared with an eye to identifying spatial and seasonal patterns. The results further demonstrate the potential utility of information theoretic concepts for assessing air quality variability; yield some new insight into tropospheric ozone dynamics across the LFV; and may provide some guidance to the refinement of monitoring network configuration. Of particular note is that, although entropy and mean concentration exhibit some similarities in their respective seasonal patterns, maximum uncertainty and information content appears to occur at times and locations somewhat different from those at which highest concentrations are experienced.  相似文献   

16.
Air toxics emission inventories play an important role in air quality regulatory activities. Recently, Minnesota Pollution Control Agency (MPCA) staff compiled a comprehensive air toxics emission inventory for 1996. While acquiring data on the mass of emissions is a necessary first step, equally important is developing information on the potential toxicity of the emitted pollutants. To account for the toxicity of the pollutants in the emission inventory, inhalation health benchmarks for acute effects, chronic effects, and cancer were used to weight the mass of emissions. The 1996 Minnesota emissions inventory results were ranked by mass of emissions and by an index comprised of emissions divided by health benchmarks. The results show that six of eight pollutants ranked highest by toxicity were also the pollutants of concern indicated in environmental monitoring data and modeling data. Monitoring data and modeling results did not show high impacts of the other two pollutants that were identified by the toxicity-based emission ranking method. The biggest limitation in this method is the lack of health benchmark values for many pollutants. Despite uncertainties and limited information, this analysis provides useful information for further targeting pollutants and source categories for control.  相似文献   

17.
Identification of pollution sources and estimation of their contribution to dioxin pollution are important for taking better countermeasures against such sources. The information based on seventeen 2,3,7,8-chlorine-substituted congeners and 10 homologues is usually not sufficient for source identification. The usefulness of detailed congener-specific information of tetra- to octachlorinated polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans was examined by principal component analysis and compared with conventional dioxin information. It was revealed that congener-specific information was far more effective for source identification than conventional information. For source apportioning, it was shown that multiple regression analysis with detailed source congener profiles could be carried out successfully when calculations were performed for individual homologues. This was because of the large variation in homologue composition in source dioxin profiles in addition to the difference in environmental behavior among the homologues.The newly proposed methods for statistical analysis were applied to the estimation of dioxin mass balance in Tokyo Bay basin. It was found that Tokyo Bay sediment core contained dioxins from three major sources: combustion, pentachlorophenol (PCP), and chloronitrophen (CNP). PCP and CNP contained large amounts of dioxin as impurity and were used extensively as paddy field herbicides in Japan in the past. The total dioxin load from the two herbicides to the basin during the past 45 years (1951-1995) was estimated to be five times larger than that from combustion source in terms of toxic equivalents (WHO-TEQ). However, in the surface sediment of the bay, the contribution from the herbicides was nearly equal to that from combustion. The herbicide contribution peaked during the 1960s and 1970s and gradually decreased thereafter.  相似文献   

18.
The focus of this paper and its companion (Part II) is to identify producer responsibility associated with the proposed Waste from Electrical and Electronic Equipment (WEEE) Directive and the need for greater information about the environmental attributes of electrical and electronic equipment to facilitate end-of-life management of discarded products. Recently, a wide-ranging debate has started within the IT industry centred on the best way to define the exact nature of the information that needs to be supplied to recyclers by producers in order to comply with the proposed European Commission Directive. Using IT and office equipment as an indicative example, semi-structured telephone interviews were conducted with representatives of the UK electronics end-of-life management industry about the environmental attributes that are needed for compliance with the draft Directive. The results of this research indicate there is specific information about equipment that is required on a regular basis, the most important of which is centred on hazardous substances and materials contained in whole units, parts and components of that equipment. The content of an eco-declaration for end-of-life management of IT and office equipment derived from quantitative and qualitative interview data is presented.  相似文献   

19.
ABSTRACT

A methodology is presented for estimating the probability that particular classes of environmental contaminants will be of concern at brownfield redevelopment sites. These probabilities are predicted by a logistics model that is based on qualitative information about site history and status. This qualitative information comprises data that would be collected through a Phase I Environmental Site Assessment (ESA), including historic site use, current use and ownership status, and the nature of adjacent properties. The model is fit and demonstrated using a set of 59 former industrial sites in southwestern Pennsylvania that were collected from the files of the Pennsylvania Department of Environmental Protection (PADEP). Predictive models are developed for exceedances of contaminants as grouped into the following classes: metals, chlorinated hydrocarbons, fuel hydrocarbons, and PCBs. A procedure for estimating the parametric uncertainty of the model predictions is also illustrated. This method can serve as a starting point for more effective usage of existing Phase I ESA information and for evaluation of the benefit of obtaining additional site information. By increasing the decision-making value of existing (or inexpensive) data, this method can help to reduce the information asymmetry that may be an obstacle to redevelopment.  相似文献   

20.
Rhizoremediation is a significant form of bioremediation for polycyclic aromatic hydrocarbons (PAHs). This study examined the role of molecular structure in determining the rhizosphere effect on PAHs dissipation. Effect size in meta-analysis was employed as activity dataset for building quantitative structure-activity relationship (QSAR) models and accumulative effect sizes of 16 PAHs were used for validation of these models. Based on the genetic algorithm combined with partial least square regression, models for comprehensive dataset, Poaceae dataset, and Fabaceae dataset were built. The results showed that information indices, calculated as information content of molecules based on the calculation of equivalence classes from the molecular graph, were the most important molecular structural indices for QSAR models of rhizosphere effect on PAHs dissipation. The QSAR model, based on the molecular structure indices and effect size, has potential to be used in studying and predicting the rhizosphere effect of PAHs dissipation.  相似文献   

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