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1.
The awareness regarding quality assurance (QA) and quality control (QC) for environmental monitoring has considerably increased in the past few years, especially with respect to the determination of chemical species, since errors occurring at various levels may considerably affect the interpretation of results (e.g. studies of toxic impact, geochemical pathways, etc.). QA for environmental analysis covers a broad range of activities from sample collection to laboratory work and the approach for ensuring quality data should be considered in a global context. However, whereas great emphasis has been placed on QA within the laboratory, there have been few systematic attempts to evaluate risks of discrepancies related, for example, to field manipulations. The situation is even worse when monitoring is applied to relatively new fields such as chemical speciation. This paper outlines some of the main aspects of quality control of environmental analysis, including the validation of methods, sampling and sample handling, storage, etc., with special emphasis on the monitoring of chemical forms of elements (e.g. species of tin, mercury, lead and selenium).  相似文献   

2.
In environmental studies statistics is too often used as a salvage operation, or as an attempt to show significance in the absence of any clear hypothesis. Good design is needed, not fancier statistics. Too often we pursue short-term problems that are in fashion rather than study long-term environmental deterioration that really matters. Since change-often unpredictable change-is an intrinsic part of nature, it is pointless to fight all environmental change. We must choose our level of concern and then influence environmental change where we can. The judgement on whether a given change is bad cannot be left to the statistician or to statistical tests; the politician in consultation with the ecologist are responsible for it. The statistical significance of a hypothesized impact-related change should be tested against year-to-year variation in the unimpacted situation rather than against replicate sampling error. This is another argument for long-term studies. Attributes of good design and appropriate criterion and predictor variables are discussed.Paper presented at a Symposium held on 20–21 April 1982, in Edmonton, Alberta, Canada.  相似文献   

3.
介绍了采用美国达拉斯 (Dallas)半导体公司近年推出的单总线技术研制的自动气象站 ,它很适用于对地面气象参数的监测。论述了用单总线技术改造原来人工监测的实施方案。该系统也可广泛用于关心气象信息的各种部门  相似文献   

4.
应用逼近于理想解的排序法优选环境监测点位的研究   总被引:4,自引:1,他引:3  
尝试应用逼近于理想解的排序法进行环境监测点位的研究,证明此法具有简便、易行、实用性和科学性较强的特点.  相似文献   

5.
Modern airborne and satellite remote sensing techniques offer attractive opportunities to coastal monitoring systems. Improvements of the evaluation of larger scales phenomena and processes due to the synopticity of the remote sensing data are of particular interest. However, some uncertainties and limitations about remote sensing must be considered. Microwave, infrared and visible radiation methods and their applications are briefly discussed and some applications are demonstrated. Special attention is paid to the remote sensing of various pollutants in the sea, in particular with respect to oil pollution.Promising developments of the remote sensing methods for coastal monitoring are to be expected from the European remote sensing satellite missions ERS 1 and ERS 2.Combination of these observations with simultaneous in situ measurements from ships (sea truth) appears to be most advantageous for the interpretation of the collected data.  相似文献   

6.
The identification of an indicator for monitoring pesticides is a very effective analytical approach because it allows one to schedule and simplify the analytical routine. In this study, a new indicator has been designed, which has to be able to define a scale of priorities in the pesticides monitoring. A starting equation was developed involving the escaping tendency of a given substance from a phase (based on the Mackay model I level). The reliability of the indicator was tested by application to a model system, consisting of a defined and limited area, choosing water as matrix over a period of 6 years. A group of marker compounds was also defined to implement the predictive efficacy of the indicator. The results obtained by modeling were compared to those obtained by experimentation of the same model system. The indicator was subsequently and appropriately modified creating a new equation, including a kinetic factor, which considers the environmental degradation processes. The effect of the rectified indicator was consistent with the sales data list of compounds, when applied to the markers. The indicator developed in this study, tested as a model on specific area-phase-period (Province of Siena, water phase, 2000?C2006), is applicable to any other area-phase-period, adjusting the partition value of the Mackay model for the case under study.  相似文献   

7.
The problem of determining sample size for environmental monitoring and assessment is considered. Hypothesis testing is discussed in general terms and in terms of monitoring toxic chemical sites. Competing risks of misclassification of sites are examined within the framework of statistics. Alpha and beta, the probability of making Type I and Type II errors, respectively, are illustrated in the context of environmental monitoring.Sample size formulas and tables are provided for comparing a mean to a standard mean, comparing two means, comparing a proportion to a standard proportion, and comparing two proportions. The formulas and tables consider the size of differences to be detected as well as the probability of Type I and Type II errors.Although the research described in this article has been funded wholly or in part by the United States Environmental Protection Agency through Cooperative Agreement No. CR 810550 to the University of Nevada, Las Vegas, it has not been subjected to the Agency review and therefore does not necessarily reflect the views of the Agency and no official endorsement should be inferred.  相似文献   

8.
实验室认可与环境监测管理   总被引:1,自引:0,他引:1  
根据哈尔滨市环境监测站实验室认可工作体会,分析了环境监测实验室开展实验室认可的意义,着重探讨了实验室认可对提高监测站监测管理水平的重大作用。  相似文献   

9.
10.
Recent developments in wireless sensor technology afford the opportunity to rapidly and easily deploy large-scale, low-cost, and low-power sensor networks across relatively sizeable environmental regions. Furthermore, the advancement of increasingly smaller and less expensive wireless hardware is further complemented by the rapid development of open-source software components. These software protocols allow for interfacing with the hardware to program and configure the onboard processing and communication settings. In general, a wireless sensor network topology consists of an array of microprocessor boards, referred to as motes, which can engage in two-way communication among each other as well as with a base station that relays the mote data to a host computer. The information can then be either logged and displayed on the local host or directed to an http server for network monitoring remote from the site. A number of wireless sensor products are available that offer off-the-shelf network hardware as well as sensor solutions for environmental monitoring that are compatible with the TinyOS open-source software platform. This paper presents an introduction to wireless sensing and to the use of external antennas for increasing the antenna radiation intensity and shaping signal directivity for monitoring applications requiring larger mote-to-mote communication distances.  相似文献   

11.
In many environmental monitoring and impact assessment processes, Indigenous communities are treated as intellectually homogenous and intracultural variation in environmental knowledge often goes unaccounted for. This not only poses obvious risks to the effectiveness of environmental impact assessments but also gives standing to those who question the credibility of traditional ecological knowledge and its contribution to environmental monitoring and assessment programs altogether. In this paper we describe the steps that were taken to account for intracultural variability in First Nation knowledge of fish and the potential impacts associated with the Peace River oil sands development in Alberta, Canada. Involving the delivery of a household survey to 1,127 First Nation households in 11 Peace River communities, our approach was successful in identifying regional, community, and household variability in fishing activity, and has allowed us to differentiate novice from expert knowledge holders. This research demonstrates the need to account for intracultural variability in First Nations environmental knowledge in order for traditional ecological knowledge to make meaningful contributions to environmental monitoring and assessment programs.  相似文献   

12.
The advancement in miniaturization and microfabrication technology has led to the development of sensitive and selective electrochemical devices for field-based and in situ environmental monitoring. Electrochemical sensing devices have a major impact upon the monitoring of priority pollutants by allowing the instrument to be taken to the sample (rather than the traditional way of bringing the sample to the laboratory). Such devices can perform automated chemical analyses in complex matrices and provide rapid, reliable and inexpensive measurements of a variety of inorganic and organic pollutants. Although not exhaustive due to the vast amounts of new and exciting electrochemical research, this review addresses many important advances in electrochemical sensor design and development for environmental monitoring purposes. Critical design factors and development issues including analytical improvements (e.g. detection limits), microfabrication and remote communication are presented. In addition, modern environmental applications will be discussed and future perspectives considered.  相似文献   

13.
Synthetic musks (nitro and polycyclic musks) are a group of chemicals offering a wide range of important properties for environmental monitoring programs. They are produced as odorous chemicals and added to a wide variety of perfumes, toiletry products and other household products. As such, they are directly applied in cosmetic products or in washed textiles to the human body in considerable concentrations and accumulate owing to dermal resorption. In addition, synthetic musks also enter the environment via waste water treatment. Several polycyclic musks are chiral. By using chiral gas chromatographic methods, it is possible to determine the enantiomeric ratio and assess their bioavailability. Although an comprehensive quality assurance program must be followed during the analysis of synthetic musks in environmental samples, the determination of these compounds is not very demanding and can be carried out by a standard analytical laboratory specialising in trace analysis of organic pollutants. Owing to the pheromone-like behavior of some synthetic musks, the induction of receptors in olfactory systems should be investigated. For HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran, e.g., Galaxolide), three-dimensional structural similarities with androstenone (5 alpha-androst-16-en-3-one), a mammalian steroid pheromone, were found, which support the hypothesis of HHCB as an artificial pheromone. Owing to their environmental abundance, their relation to human activities and their potential for pheromone-like environmental behavior, synthetic musks are especially valuable as future indicator chemicals for environmental monitoring.  相似文献   

14.
15.
环境监测实验室的环境污染与防治   总被引:12,自引:1,他引:12  
主要分析了环境监测实验室产生的污染特点 ,指出环境监测实验室是一类典型的小型污染源。同时详细阐述了环境监测实验室防治污染、加强实验室环境管理的几种途径  相似文献   

16.
Continuous, in situ monitoring of air, water and land quality is fundamental to most environmental applications. Low cost and non-invasive chemical sensor arrays provide a suitable technique for in situ monitoring. Their ability and performance under realistic conditions is discussed in this paper. Published studies report promising results despite a number of limitations that are associated with both the technology itself and its application in ever changing ambient conditions. Early investigations include the analysis of single substances as well as odour and wastewater organic load monitoring. Reported applications typically highlight the sensitivity of the currently available sensors to changes in temperature, humidity and flow rate. Two types of approaches are recommended to deal with these effects: either working under fixed experimental conditions or measuring the external parameters to numerically compensate for their change. The main challenge associated with the use of non-specific sensor arrays lies in establishing a relationship between the measured multivariate signals and the standards metrics that are traditionally used for quality assessment of gas mixtures. For instance, odour monitoring requires calibration against olfactometric measurements while investigations of wastewater samples still need to be correlated with organic pollution parameters such as BOD, COD or TOC. On the other hand, results obtained in the field have demonstrated how sensor arrays can be readily used as simple alarm devices or as early warning systems based on a general air/water quality index.  相似文献   

17.
18.
In 1991, a collaborative project to revise the terrestrial component of a national ecological framework was undertaken with a wide range of stakeholders. This spatial framework consists of multiple, nested levels of ecological generalization with linkages to existing federal and provincial scientific databases. The broadest level of generalization is the ecozone. Macroclimate, major vegetation types and subcontinental scale physiographic formations constitute the definitive components of these major ecosystems. Ecozones are subdivided into approximately 200 ecoregions which are based on properties like regional physiography, surficial geology, climate, vegetation, soil, water and fauna. The ecozone and ecoregion levels of the framework have been depicted on a national map coverage at 1:7 500 000 scale. Ecoregions have been subdivided into ecodistricts based primarily on landform, parent material, topography, soils, waterbodies and vegetation at a scale (1:2 000 000) useful for environmental resource management, monitoring and modelling activities. Nested within the ecodistricts are the polygons that make up the Soil Landscapes of Canada series of 1:1 000 000 scale soil maps. The framework is supported by an ARC-INFO GIS at Agriculture Canada. The data model allows linkage to associated databases on climate, land use and socio-economic attributes.  相似文献   

19.
Methods to monitor contamination of workplaces with antineoplastic drugs have been developed and validated. Cyclophosphamide (CP) was used as a model compound as it is one of the most commonly used antineoplastic drugs. A wipe sampling method to detect contamination with CP at surfaces was developed. A personal air sampling method to sample gas and vapour on solid sorbent tubes and particles with filters was also developed. Wipe and filter samples were extracted and sorbent samples were eluted, all with ethyl acetate. The samples were analysed with liquid chromatography tandem mass spectrometry. (2)H(6)-labelled cyclophosphamide was used as an internal standard. The between-day precision was 2-5% for wipe samples, 4-6% for sorbent samples and 3-8% for filter samples. The limit of detection was 0.02 ng CP per sample for the wipe and filter methods and 0.03 ng CP per sample for the solid sorbent method. Wipe sampling on surfaces made of different materials resulted in mean recoveries between 78-106%. The desorption recovery was between 97-102% for the wipe samples, 97% for the sorbent samples and 101% for the filter samples. Samples were stable for up to 2 months at 5 degrees C and -20 degrees C and for about 2 d at room temperature. The developed methods were applied to the measurement of contamination with CP in a hospital pharmacy. Trace amounts of CP, 1.3 and 1.4 ng, were detected on surfaces in the pharmacy.  相似文献   

20.
The ability to sample in situ natural environmental processes has proven to be challenging when working with redox-sensitive contaminates in saturated sediments in wetland systems, especially within the rhizosphere, where sharp redox gradients are common. Many traditional approaches are invasive and disturb natural sediment chemistry. Through laboratory and field studies, the work presented in this study demonstrates a novel semipermanent dialysis sampler that allows for long-term, anaerobic monitoring of shallow sediments. Dialysis samplers were deployed and tested for over 1 year while being exposed to extremes in climate. These newly designed devices produce statistically reproducible data and capture sensitive redox trends. Results from the newly designed samplers were compared to conventional samplers. Initially, both the new and old designs yielded statistically similar data, but these data diverged over a period of months. The new devices are less invasive, so data gathered from these devices are more likely to be a closer representation of true conditions in the subsurface. By giving reliable data from a consistent location in space, these new samplers represent a significant step forward in capturing spatial and temporal variability in wetland redox chemistry during long-term monitoring.  相似文献   

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