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1.
间隔流动分析仪在环境监测应用中的评估报告   总被引:3,自引:0,他引:3  
根据本站购置的SFA-2000型间隔流动分析仪的调试和应用情况,对该类仪器在环境监测工作中的应用状况和前景进行了比较评估,并提出了在购置该类仪器时所应注意的问题和配置方案。  相似文献   

2.
新《大气污染防治法》施行,环境监测数据面临考验   总被引:1,自引:0,他引:1  
新修订的《中华人民共和国大气污染防治法》确立了超标排污违法的法律地位 ,监测数据将作为实施环境行政处罚的依据。文章从行政处罚、行政复议和行政诉讼三个方面 ,阐述了确保监测数据权威性的重要意义 ;介绍了对废气污染源排放进行监测所存在的问题 ,提出了确保监测数据权威性的建议 ,为环境行政处罚顺利实施提供准确的法律依据。  相似文献   

3.
The Ko factor method in neutron activation analysis adopts all the principles of comparator method and can be used for the rapid determination of elemental comcentrations during routine monitoring of environmental samples. The method necessiates the use of same in-pile conditions, such as irradiation time, irradiation position and the type of neutron spectrum, for which the factors have been generated. The K_o factors were estimated for various elements of environmental importance for three irradiation positions of Apsara Reactor at Bhabha Atomic Research Centre. Standard reference materials of soil and coal were used for all the elements except for Hg for which HgCl2 was used. The concentration of the elements determined using these factors in a flyash standard reference material revealed good agreement within 10% of the certified values. The efficacy of the method compared well with that of specific element comparator method as revealed by the elemental concentrations obtained by both the techniques.  相似文献   

4.
讨论了环境监测分析中有关量筒、移液管、容量瓶、滴定管、托盘天平、比色皿等仪器的简化操作方法 ,这对于分析人员提高分析速度和分析准确度具有很强的实用性  相似文献   

5.
The present study is focused on the implementation of a novel, low cost, urban grid of nanostructured chemresistor gas sensors for ammonia concentration ([NH(3)]) monitoring, with NH(3) being one of the main precursors of secondary fine particulate. Low-cost chemresistor gas sensors based on carbon nanotubes have been developed, their response to [NH(3)] in the 0.17-5.0 ppm range has been tested, and the devices have been properly calibrated under different relative humidity conditions in the 33-63% range. In order to improve the chemresistor selectivity towards [NH(3)], an Expert System, based on fuzzy logic and genetic algorithms, has been developed to extract the atmospheric [NH(3)] (with a sensitivity of a few ppb) from the output signal of a model chemresistor gas sensor exposed to an NO(2), NO(X) and O(3) gas mixture. The concentration of these pollutants that are known to be the most significant interfering compounds during ammonia detection with carbon nanotube gas sensors has been tracked by the ARPA monitoring network in the city of Milan and the historical dataset collected over one year has been used to train the Expert System.  相似文献   

6.
The main problem of traditional methods of environmental impact assessment (EIA) is that in most of the existing algorithms and methods, such as Leopold, Folchi and RIAM, the main attention is to the destructive effects of the proposed plan, and the advantages of the industrial project are less noticeable. This has led to a permanent challenge between environmental organizations and industrial stakeholders. Data envelopment analysis (DEA) is a new approach of assessing the industrial units. Besides, it considers the positive economic and social impacts of the project and provides a comprehensive assessment of the industrial unit. With this approach, the environmental impacts of an industrial unit have been considered as “inputs” and its positive economic and social impacts considered as the “outputs” of the DEA models. Therefore, the problem of impact assessment changes into a DEA model. In the present study, the Alborz Sharghi Coal washing plant in northern Iran has been considered as a case study for implementing the DEA-EIA approach, and 19 plant activities and 11 environmental components have been used to evaluate the environmental effects of the plant. To solve the EIA problem, two commonly used DEA approaches, called CRS (constant returns to scale) and VRS (variable returns to scale), have been used. The DEA results identified the critical environmental components of the plant that should be considered seriously. Also, drawing the “potential improvement” diagram in the DEA method is an effective tool for determining the high risk activities of the factory and applying them in development plans. Besides, using the VRS model with maximize-output approach showed that some of the plant activities had the most differences with optimal mode and these components should be considered in future development plans. Finally, it can be concluded that, assessing the environmental impacts of the mineral industries with VRS maximize-output approach, is closer to the concept of sustainable development and cost-benefit analysis.  相似文献   

7.
It is crucial for environmental monitoring to fully control temporal bias, which is the distortion of real data evolution by varying bias through time. Temporal bias cannot be fully controlled by statistics alone but requires appropriate and sufficient metadata, which should be under rigorous and continuous quality assurance and control (QA/QC) to reliably document the degree of consistency of the monitoring system. All presented strategies to detect and control temporal data bias (QA/QC, harmonisation/homogenisation/standardisation, mass balance approach, use of tracers and analogues and control of changing boundary conditions) rely on metadata. The Will Rogers phenomenon, due to subsequent reclassification, is a particular source of temporal data bias introduced to environmental monitoring here. Sources and effects of temporal data bias are illustrated by examples from the Swiss soil monitoring network. The attempt to make a comprehensive compilation and assessment of required metadata for soil contamination monitoring reveals that most metadata are still far from being reliable. This leads to the conclusion that progress in environmental monitoring means further development of the concept of environmental metadata for the sake of temporal data bias control as a prerequisite for reliable interpretations and decisions.  相似文献   

8.
In estimating spatial means of environmental variables of a region from datacollected by convenience or purposive sampling, validity of the results canbe ensured by collecting additional data through probability sampling. Theprecision of the estimator that uses the probability sample can beincreased by interpolating the values at the nonprobability sample points tothe probability sample points, and using these interpolated values as anauxiliary variable in the difference or regression estimator. Theseestimators are (approximately) unbiased, even when the nonprobability sampleis severely biased such as in preferential samples. The gain in precisioncompared to the estimator in combination with Simple Random Samplingis controlled by the correlation between the target variable andinterpolated variable. This correlation is determined by the size (density)and spatial coverage of the nonprobability sample, and the spatialcontinuity of the target variable. In a case study the average ratio of thevariances of the simple regression estimator and estimator was 0.68for preferential samples of size 150 with moderate spatial clustering, and0.80 for preferential samples of similar size with strong spatialclustering. In the latter case the simple regression estimator wassubstantially more precise than the simple difference estimator.  相似文献   

9.
The Special Monitoring of Applied Response Technologies (SMART) program was used during the Deepwater Horizon oil spill as a strategy to monitor the effectiveness of sea surface dispersant use. Although SMART was implemented during aerial and vessel dispersant applications, this analysis centers on the effort of a special dispersant missions onboard the M/V International Peace, which evaluated the effectiveness of surface dispersant applications by vessel only. Water samples (n?=?120) were collected from background sites, and under naturally and chemically dispersed oil slicks, and were analyzed for polycyclic aromatic hydrocarbons (TPAHs), total petroleum hydrocarbons (TPH), and a chemical marker of Corexit® (dipropylene glycol n-butyl ether, DPnB). Water chemistry results were analyzed relative to SMART field assessments of dispersant effectiveness (“not effective,” “effective,” and “very effective”), based on in situ fluorometry. Chemistry data were also used to indirectly determine if the use of dispersants increased the risk of acute effects to water column biota, by comparison to toxicity benchmarks. TPAH and TPH concentrations in background, and naturally and chemically dispersed samples were extremely variable, and differences were not statistically detected across sample types. Ratios of TPAH and TPH between chemically and naturally dispersed samples provided a quantitative measure of dispersant effectiveness over natural oil dispersion alone, and were in reasonable agreement with SMART field assessments of dispersant effectiveness. Samples from “effective” and “very effective” dispersant applications had ratios of TPAH and TPH up to 35 and 64, respectively. In two samples from an “effective” dispersant application, TPHs and TPAHs exceeded acute benchmarks (0.81 mg/L and 8 μg/L, respectively), while none exceeded DPnB’s chronic value (1,000 μg/L). Although the primary goal of the SMART program is to provide near real-time effectiveness data to the response, and not to address concerns regarding acute biological effects, the analyses presented here demonstrate that SMART can generate information of value to a larger scientific audience. A series of recommendations for future SMART planning are also provided.  相似文献   

10.
This paper discusses various methods for calculating the minimum instream flows for the protection of aquatic life for the purpose of illustrating its increasing complexity. These procedures are the Montana method (Tennant, 1976); the wetted perimeter method (Collings, 1974; Cochnauer, 1976) and the IFIM method (Instream Flow Incremental Methodology; Bovee, 1982). An analysis is then made of some regionalisation criteria based on these methods, from which useful suggestions can be drawn for the development of a procedure to be applied to basins. A method is thus proposed for calculating the recommended flows for protecting the aquatic environment based on simple hydrological variables, such as Q7 10, which can be estimated for a basin on the basis of area A and a Base Flow Index (BFI) which summarises its hydrogeological characteristics. This approach can be used when the field data necessary for more complex methods is not available. These require the defining of the environmental suitability of a watercourse for certain designated reference fish species, according to the flow and the morphology of the channel. The positive results of this approach were verified by Leonard (1990) and this methodology was applied to the Tiber river basin.  相似文献   

11.
Small-bodied fishes are more commonly being used in environmental effects monitoring (EEM) studies. There is a lack of understanding of the biological characteristics of many small-bodied species, which hinders study designs for monitoring studies. For example, 72 % of fish population surveys in Canada’s EEM program for pulp and paper mills that used small-bodied fishes were conducted outside of the reproductive period of the species. This resulted in an inadequate assessment of the EEM program’s primary effect endpoint (reproduction) for these studies. The present study examined seasonal changes in liver size, gonad size, and condition in seven freshwater and estuarine small-bodied fishes in Atlantic Canada. These data were used to examine differences in reproductive strategies and patterns of energy storage among species. Female gonadal recrudescence in all seven species began primarily in the 2-month period in the spring before spawning. Male gonadal development was concurrent with females in five species; however, gonadal recrudescence began in the fall in male three-spined stickleback (Gasterosteus aculeatus) and slimy sculpin (Cottus cognatus). The spawning period for each species was estimated from the decline in relative ovary size after its seasonal maximum value in spring. The duration of the spawning period reflected the reproductive strategy (single vs multiple spawning) of the species. Optimal sampling periods to assess reproductive impacts in each species were determined based on seasonal changes in ovary size and were identified to be during the prespawning period when gonads are developing and variability in relative gonad size is at a minimum.  相似文献   

12.
13.
This is the second part of the study on sensitivity analysis of the technique for order preference by similarity to ideal solution (TOPSIS) method in water quality assessment. In the present study, the sensitivity of the TOPSIS method to the index input data was investigated. The sensitivity was first theoretically analyzed under two major assumptions. One assumption was that one index or more of the samples were perturbed with the same ratio while other indices kept unchanged. The other one was that all indices of a given sample were changed simultaneously with the same ratio, while the indices of other samples were unchanged. Furthermore, a case study under assumption 2 was also carried out in this paper. When the same indices of different water samples are changed simultaneously with the same variation ratio, the final water quality assessment results will not be influenced at all. When the input data of all indices of a given sample are perturbed with the same variation ratio, the assessment values of all samples will be influenced theoretically. However, the case study shows that only the perturbed sample is sensitive to the variation, and a simple linear equation representing the relation between the closeness coefficient (CC) values of the perturbed sample and variation ratios can be derived under the assumption 2. This linear equation can be used for determining the sample orders under various variation ratios.  相似文献   

14.
Some health important enteric viruses are considered to be emerging waterborne pathogens and so the improvement of detection of these viruses in the aquatic environment is one of the most important steps in dealing with these pathogens. Since these viruses may be present in low numbers in water, it is necessary to concentrate water samples before viral detection. Although there are several methods to concentrate viruses in environmental waters, all present some drawbacks and consequently the method should be chosen that, despite its limitations, is adequate to achieve the aim of each study. As the effectiveness of the concentration methods is evaluated by determining the efficiency of viral recovery after concentration, it is important to use a simple and effective approach to evaluate their recovery efficiency. In this work ultracentrifugation, usually used as a secondary step for virus concentration, was evaluated as the main method to concentrate directly viruses in environmental water samples, using the microscopic enumeration of virus-like particles (VLP) as a new approach to estimate the efficiency of recovery. As the flocculation method is currently employed to concentrate viruses in environmental waters, it was also used in this study to assess the efficiency of the ultracentrifugation as the main viral concentration method in environmental waters. The results of this study indicate that ultracentrifugation is an adequate approach to concentrate viruses directly from environmental waters (recovery percentages between 66 and 72% in wastewaters and between 66 and 76% in recreational waters) and that the determination of VLP by epifluorescence microscopy is a simple, fast and cheap alternative approach to determine the recovery efficiency of the viral concentration methods.  相似文献   

15.
Mechanistic hydrologic and water quality models provide useful alternatives for estimating water quality in unmonitored streams. However, developing these elaborate models for large watersheds can be time-consuming and expensive, in addition to challenges that arise during calibration when there is limited spatial and/or temporal monitored in-stream water quality data. The main objective of this research was to investigate different approaches for developing multivariate analysis models as alternative methods for rapidly assessing relationships between spatio-temporal physical attributes of the watershed and water quality conditions in monitored streams, and then using the developed relationships for estimating water quality conditions in unmonitored streams. The study compares the use of various statistical estimates (mean, geometric mean, trimmed mean, and median) of monitored water quality variables to represent annual and seasonal water quality conditions. The relationship between these estimates and the spatial data is then modeled via linear and non-linear multivariate methods. Overall, the non-linear techniques for classification outperformed the linear techniques with an average cross-validation accuracy of 79.7%. Additionally, the geometric mean based models outperformed models based on other statistical indicators with an average cross-validation accuracy of 80.2%. Dividing the data into annual and quarterly datasets also offered important insights into the behavior of certain water quality variables impacted by seasonal variations. The research provides useful guidance on the use and interpretation of the various statistical estimates and statistical models for multivariate water quality analyses.  相似文献   

16.
As part of the Environmental Impact Assessment and Habitats Regulations Assessment process, developers are required to assess the indirect effects of fish entrapment however, presently there is little guidance to support quantitative assessments of food resource losses to higher trophic levels. To address this gap, a detailed and quantitative tool termed Dietary Equivalence Analysis is presented in this paper. Dietary Equivalence Analysis combines bioenergetic modelling with dietary and demographic information to express entrapment predictions in terms of the number of marine predators, or the proportion of a population, that would be sustained by the biomass of fish prey had it not been entrapped. The application of this tool is demonstrated by way of a worked example and includes a sensitivity analysis using Monte Carlo simulation to determine the influence of input parameter uncertainty on dietary equivalence estimates. It is shown that the Dietary Equivalence Analysis framework can be used to develop project- and regional-specific quantitative assessments for a number of marine predators. This is considered to provide competent authorities with a new and more realistic perspective from which the magnitude of predicted fish entrapment effects can be viewed and assessed.  相似文献   

17.
Private or public developers, including local authorities and government agencies, have limited operational guidance to include case-relevant health information in environmental reports. In Italy, the absence of technical indications prompted the Ministry of Health to construct a new model of Health Impact Assessment (HIA) for health integration in Environmental Assessment (EA) processes. A coordinating committee set within an inter-institutional working group was assisted by public and private key stakeholders to deliver guidance on HIA. The three research stages of framing, production and delivery were carried out to: (1) frame the context for HIA guidance implementation; (2) produce the operational guideline and tools; (3) train and disclose the guideline to final users. The guideline and the operational procedures were informed by core criteria to achieve a health standard in environmental reporting. The procedures guide the user to carry out a comprehensive assessment of the population health based on the broad determinants. The environmental reporting integrates health through functional components, divided into levels and supported by related flowcharts and checklists. HIA knowledge and skills were provided to facilitate the guideline utilization within the health departments. The guideline embedded the existing EA national legacy, normative and technical. The entire decisional cycle, from strategic planning to project development was covered in the guideline including the screen of proposals. The experience triggered the definition of an environmental health collaborative platform under the Ministry of Health coordination to fill gaps in competence building, sector operational tools development, methodologies harmonization on the national territory.  相似文献   

18.
Economic losses caused by tropical cyclones have increased dramatically. Historical changes in losses are a result of meteorological factors (changes in the incidence of severe cyclones, whether due to natural climate variability or as a result of human activity) and socio-economic factors (increased prosperity and a greater tendency for people to settle in exposed areas). This paper aims to isolate the socio-economic effects and ascertain the potential impact of climate change on this trend. Storm losses for the period 1950–2005 have been adjusted to the value of capital stock in 2005 so that any remaining trend cannot be ascribed to socio-economic developments. For this, we introduce a new approach to adjusting losses based on the change in capital stock at risk. Storm losses are mainly determined by the intensity of the storm and the material assets, such as property and infrastructure, located in the region affected. We therefore adjust the losses to exclude increases in the capital stock of the affected region. No trend is found for the period 1950–2005 as a whole. In the period 1971–2005, since the beginning of a trend towards increased intense cyclone activity, losses excluding socio-economic effects show an annual increase of 4% per annum. This increase must therefore be at least due to the impact of natural climate variability but, more likely than not, also due to anthropogenic forcings.  相似文献   

19.
Arsenic(III), selenium(IV), copper(II), lead(II), cadmium(II),zinc(II) have been determined in sea water, sediments, algae andclams by differential pulse cathodic (DPCSV) and anodic (DPASV)stripping voltammetry. The voltammetric measurements are carriedout using a conventional three-electrode cell and the ammonia-ammonium chloride buffer pH 9.2 as supporting electrolyte.The analytical procedure has been verified by the analysisof the standard reference materials (Estuarine SedimentBCR-CRM 277, Ulva Lactuca BCR-CRM 279 and Mussel Tissue BCR-CRM278). The precision and the accuracy are less than 5%. Thisprocedure is utilized for the monitoring of heavy metals inthe Po river mouth area (Italy).  相似文献   

20.
Groundwater flow at Kharga Oasis, located in the western desert of Egypt, was previously analyzed using numerical models; however, the lack of basic data often limits the implementation of these models, as well as introducing a problem for model calibration and validation. The Grey Model (GM) was used to overcome these difficulties of data limitation and uncertainty of hydrogeological conditions. However, no clear theories exist for selecting the number of input model trends and the most suitable values of input parameters. Therefore, in the current study, a modification of the GM is newly proposed and called the Modified Grey Model (MGM) in an attempt to determine a process for selecting the best input models' trends with the appropriate values of input parameters to achieve acceptable fitting to observations. The sensitivity analysis results showed that the MGM produced more stable results than the GM using a wide range of values for input parameters. Moreover, the MGM reduced the calculation time required for fitting the measured piezometric level trends by 99.8 %. Three development scenarios of groundwater withdrawal were proposed that involved either expanding the present extraction rate or redistributing the groundwater withdrawal over the recent working production wells (RWPWs). The results concluded that the groundwater table in the northern part of the oasis could be temporally recovered to an economical piezometric level; however, the table in the southern part is severely decreased. Therefore, new production wells are recommended to be constructed in the southern part far enough from the RWPWs.  相似文献   

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