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1.
Data management is becoming increasingly simple and complex at the same time. The challenge is to effectively use the increasing number of tools available to manage increasing amounts of environmental information for purposes of data capture, analysis, display, sharing and storage. Government is no longer the main collector and provider of data. Community groups possess vast amounts of data collected through daily work of monitoring the environment in their local community. The chief concerns are data access, sharing, integrity and comparability. The capacity of groups to sustain data management is the key to making the sharing possible. The Southeast Environmental Association has been working with Environment Canada to develop a community, on-line database that will be linked to other geo-spatial data sets to allow instant access to geo-referenced data.  相似文献   

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Dermal exposure to pesticides is one of the main sanitaryproblems which greenhouses workers face. With the dual aimsof establishing both the body part that receives the greatestexposure and the variable that has greatest influence on this exposure level, 22 pesticide application trials were performed. Trials were carried out in different greenhouse vegetable crops,using different pesticides and different spray diameters from the spray gun. In order to determine dermal exposure, the wholebody method was used. Pieces of the applicator suit were subject to an extraction procedure and their pesticide contentdetermined using GC-NPD analysis. Multivariate analysis were applied to the data obtained. Principal component analysis showed that all trials produced a high exposure level on lowerleft leg and lower right leg. Cluster analysis distinguished between three sample groups. The most and the least affectedparts were clearly distinguished. Discriminant analysis indicated that the thin drop size of the spray gun is responsible for both the differences between groups and the minimum or maximum exposure level measured on the applicatorsuit. Therefore, selecting the variables, lower legs and thindrop size, is considered fundamental in designing programs formonitoring pesticide exposure.  相似文献   

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The rapid development of social media has accelerated the online rumor propagation, making social conflicts more intense during the development of NIMBY facilities. The “fake news” issue is not new, as the consequences will be amplified when the fakery spreads on social media as online rumors. However, few studies have been undertaken on the online public opinion, especially the rumor propagation on NIMBYism. This study collects data related to the anti-PX demonstration in Maoming city in 2014 on the Weibo platform. To form the rumor text library, qualitative research method is adopted to encode the collected data. Based on the social amplification of risk framework, three sub-frameworks are proposed in this study and statistical method is used to analyze the topics of rumors. Meanwhile, the textual content analysis and impact factor analysis is employed to examine the semantic features of rumor texts and the key role of rumor-mongers respectively. The results show that there are three main propagation lifecycles of rumors while the topics of rumors vary according to the cycle. Rumors belonging to each framework have diverse trend and the assessment framework is dominant throughout the process. “Individuals” and “Elites” are the main force of rumor spreading, and “Media practitioners” are the opinion leaders. These findings are useful for governments to establish a rumor detection system so that official information can be released and rumors can be refuted without delay. Meanwhile, the cooperation with the opinion leaders in online rumor propagation should be strengthened. In addition, a scientific popularization and timely notification of project progress is recommended prior to the development of NIMBY facility.  相似文献   

5.
大气颗粒物中多环芳烃的源解析方法   总被引:10,自引:0,他引:10       下载免费PDF全文
综述了用于大气颗粒物中多环芳烃(PAHs)源解析的主要定性、定量方法、并对其优缺点作了总结。比值法多用于定性解析,化学质量平衡法(CMB)要求源的成分谱较全面,而多元统计法则要求输入的数据较多。由于缺乏各污染源较完整的PAHs成分谱,且PAHs易发生化学反应,所以CMB法难以广泛推广,而多元统计法对源成分谱,且PAHs易发生化学反应,所以CMB法难以广泛推广,而多元统计不对源成分谱要求低,且不需要考虑PAHs的降解,因而具有推广价值。  相似文献   

6.
杭州市钱塘江干支流水质多元统计分析   总被引:2,自引:0,他引:2  
运用多元统计方法分析了杭州市钱塘江干支流上26个断面的水质监测指标。利用系统聚类分析方法将断面所在河流分为3组,与钱塘江流域污染空间分布现状基本一致。对各组水质的主成分分析表明,第1组河流水质以有机污染为主,水体中氮、磷营养盐浓度较高,水体污染程度较轻,污染来源相对单一;第2组河流水体受有机物、重金属、石油类等多个污染指标的影响,水体水质较第1组差,污染来源相对复杂;第3组河流水体既有一般有机污染,也有重金属、有毒有害物质的污染,水体水质污染严重。  相似文献   

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利用新疆某县境内主要河流的水质监测资料,依据水质评价标准《地表水环境质量标准》(GB 3838-2002),评价了某县境内主要河流的环境质量,采用季节性肯达尔法进行趋势分析检验。结果表明,新疆某县境内河流水质总体优良,水质级别为Ⅰ、Ⅱ类,可以作为饮用水源地、农田灌溉用水、一般工业用水的水源。从趋势分析检验结果看,水质基本稳定,没有受到明显的人为污染。  相似文献   

8.
Current political discussions and developments indicate the importance and urgency of incorporating climate change considerations into EIA processes. The recent revision of the EU Directive 2014/52/EU on Environmental Impact Assessment (EIA) requires changes in the EIA practice of the EU member states. This paper investigates the extent to which the Environmental Impact Assessment (EIA) can contribute to an early consideration of climate change consequences in planning processes. In particular the roles of different actors in order to incorporate climate change impacts and adaptation into project planning subject to EIA at the appropriate levels are a core topic. Semi-structured expert interviews were carried out with representatives of the main infrastructure companies and institutions responsible in these sectors in Austria, which have to carry out EIA regularly. In a second step expert interviews were conducted with EIA assessors and EIA authorities in Austria and Germany, in order to examine the extent to which climate-based changes are already considered in EIA processes. This paper aims to discuss the different perspectives in the current EIA practice with regard to integrating climate change impacts as well as barriers and solutions identified by the groups of actors involved, namely project developers, environmental competent authorities and consultants (EIA assessors/practitioners). The interviews show that different groups of actors consider the topic to different degrees. Downscaling of climate change scenarios is in this context both, a critical issue with regards to availability of data and costs. Furthermore, assistance for the interpretation of relevant impacts, to be deducted from climate change scenarios, on the specific environmental issues in the area is needed. The main barriers identified by the EIA experts therefore include a lack of data as well as general uncertainty as to how far climate change should be considered in the process without reliable data but in the presence of knowledge about possible consequences at an abstract level. A joint strategy on how to cope with uncertain prognoses about main impacts on environmental issues for areas without reliable data requires a discussion and cooperation between EIA consultants and environmental authorities.  相似文献   

9.
This study sought to evaluate and propose adjustments to the water quality monitoring network of surface freshwaters in the Paraopeba river basin (Minas Gerais, Brazil), using multivariate statistical methods. A total of 13,560 valid data were analyzed for 19 water quality parameters at 30 monitoring sites, over a period of 5 years (2008–2013). The cluster analysis grouped the monitoring sites in eight groups based on similarities of water quality characteristics. This analysis made it possible to detect the most relevant monitoring stations in the river basin. The principal components analysis associated with non-parametric tests and the analysis of violation of the standards prescribed by law, allowed for identifying the most relevant parameters which must be maintained in the network (thermotolerant coliforms, total manganese, and total phosphorus). The discharge of domestic sewage and industrial wastewater, that from mining activities and diffuse pollution from agriculture and pasture areas are the main sources of pollution responsible for the surface water quality deterioration in this basin. The BP073 monitoring site presents the most degraded water quality in the Paropeba river basin. The monitoring sites BP094 and BP092 are located geographically close and they measure similar water quality, so a possible assessment of the need to maintain only one of the two in the monitoring network is suggested. Therefore, multivariate analyses were efficient to assess the adequacy of the water quality monitoring network of the Paraopeba river basin, and it can be used in other watersheds.  相似文献   

10.
A number of methods has been proposed for dealing with single-factor or factorial experiments when the requirements for performing the normal theory analysis of variance procedure are not satisfied. This paper suggests the use of the likelihood ratio statistic for testing the main effects and the interaction between the factors in two-way layout of count data following negative binomial distributions with a common dispersion parameter. The likelihood ratio statistic for testing the equality of the dispersion parameters of several groups of count data is also derived. The methods is illustrated by an example concerning the study of spatial and temporal variation of bacterial counts.  相似文献   

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