首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Quality assurance and quality control in monitoring programs   总被引:1,自引:0,他引:1  
There are three general characteristics of the data to be collected in a monitoring program that should be met in order to maximize the use and value of the data: the data quality should be known, the data type and quality should be consistent and comparable, and the data should be available and accessible. Potential problems with each of these characteristics are addressed effectively by quality assurance and quality control. One of the most important aspects of quality assurance in a monitoring program is the development of a quality assurance plan, which should identify clearly the quality of the data needed and describe in detail the planned actions to provide confidence that the program will meet its stated objectives.Quality control data, which allow for the quality and suitability of the environmental data to be evaluated and ascertained, should be collected and utilized as an integral part of the QA effort associated with a monitoring program.  相似文献   

2.
高效液相色谱法测定环境水样中嘧磺隆   总被引:2,自引:0,他引:2  
环境水体中的嘧磺隆在pH=2-3的H2SO4介质中用二氯甲烷萃取富集,然后用高压液相色谱法分离和紫外光(254nm)检测器检测,外标法定量。用此方法测定了井水和生产单位排放的综合污水中的嘧磺隆,结果满意,最大相对标准偏差为5%,样品加标回收率在93~107%之间,最低检测限量为2ng,最低检出浓度为0.004mg/L。  相似文献   

3.
Strongyloidiasis presents a major health hazard when reusing wastewater. Albendazol with a concentration of 4 mg/l, a contact time of 45 min, pH 1.2 and pH 10.2, killed the larva. The larva was also killed with a 0.03% concentration of iodine and a detention time of 30 min or a 0.04% concentration of iodine and a contact time of 10 min. The required detention time to inactivate larva in water was found to be 17 days. The minimum revealed residual chlorine to kill the larvae was 4 mg/l with 120 min of detention time, and a minimum contact time was found to be 80 min with a residual of 23 mg/l. Many methods are available to inactivate the Strongyloides stercoralis, which could be acids, alkaline chemicals, larvicidal chemicals, super chlorination, or just detention time. The best method must be determined according to the prevailing specific environmental site and the feasibility of the selected method(s).  相似文献   

4.
This paper discusses equity issues in relation to climate change. Models of long-term climate assessments study changes in relative prices. These changes lead to gains and losses for different economic actors and these consequences are held responsible for problems related to social acceptability. Policy recommendations issued by such models cannot be put into practice. Equity should be integrated into those models in order to make them more relevant for policy. This paper considers this problem in three parts.The first part shows that equity is only one aspect of the social dimension of sustainable development, which cannot be treated separately. It invites an understanding of complexity. Equity is also interrelated with the economic and ecological dimensions of sustainable development.The second part deals with the fact that different aspects of equity have to be taken into account and several concepts of equity co-exist. If only distribution of income is taken into account, equity can effectively be addressed through economic growth, but the specific characteristics of sustainable development are left out of the analysis.Therefore, the third part is a questioning of traditional modelling approaches and of the reasons why modelling should be carried out. The paper concludes with a short discussion about the normative content of any attempt to model climate change.  相似文献   

5.
A study of the elemental leachability and retention capability of compost   总被引:2,自引:0,他引:2  
In this work a comparison is made between the different approaches that can be taken to evaluate the mobility of elements in compost. The practical consequences of the results obtained are also discussed in terms of methods for cleaning up compost and using compost in environmental remediation. The mobility of potentially toxic elements in compost is evaluated by leaching with four selected eluents, i.e. diluted sulfuric acid, oxalate, citrate and EDTA. In contrast to the chelating agents, diluted sulfuric acid was found to generally have a low leaching capability for removal of heavy metals from compost. This implies that the risk of heavy metal leaching caused by natural rainfall is likely to be low. The results obtained in the leaching experiment were compared with previous results obtained from sequential fractionation. This comparison confirmed that both methods gave similar results for predicting the lability of elements in compost. A non-linear regression analysis of the leaching curves was also conducted. The leaching curves for elements with high lability could be fitted with a two components model. The labile components identified by the kinetic model are approximately in accordance with the fractions obtained from the first step of the sequential extraction method. The kinetic speciation method is shown to be a relatively rapid and simple procedure for compost which gives more information about element lability than simple leaching experiments. The leaching reagents used in this work were not effective enough to be used for cleaning up compost with a high metal content. Compost was however shown to have a high affinity for heavy metals, with the order of affinity of metal for the compost being very similar to that seen for humic acid. Compost may therefore prove to be a good remediation material for metal contaminated waste.  相似文献   

6.
A model is developed to predict annual and total above-ground carbon storage within a hybrid poplar stream buffer. The regression model predicts tree wet weight based upon circumference at breast-height (137 cm) with an r-square value of 0.9922. Carbon storage in above-ground biomass is estimated to be 3.57 to 3.71 metric tons per hectare, with a measured annual increment of 0.92 to 1.37 metric ton per hectare per year. The variability of carbon storage within this biological system, including soil organic matter, is explored, and the number of samples required to achieve a desired level of statistical certainty are predicted. As has been investigated previously for other biological systems (Garten and Wullschleger, 1999), the study shows that a prohibitively large number of samples must be taken in order to achieve high degrees of certainty about mean carbon storage values. The study also shows, however, that mean values with somewhat greater uncertainties can easily be achieved with much smaller sample sizes. Thus carbon sequestration verification might be accomplished cost-effectively if the degree of certainty required is not unrealistically high for highly variable natural systems.  相似文献   

7.
高氟水沸石除氟的效果研究   总被引:2,自引:0,他引:2  
通过静态搅拌实验和恒温震荡实验,研究了接触时间、pH、温度及反复使用次数对沸石除氟效果的影响.结果表明,在适宜的条件下,沸石除氟效果随着使用次数的增多有上升趋势,除氟效果良好,适用于我国高氟水地区.  相似文献   

8.
Natural resource managers must know the condition of resources entrusted to their steward-ship so that they can maintain unimpaired resources and know when to restore impaired ecosystems. Resource monitoring programs should be designed to provide indications of ecosystem health, define limits of normal variation, identify abnormal conditions, and suggest potential agents of abnormal changes. Development of a conceptual model that identifies all ecosystem components and their relationships is the first step in the design of such a diagnostic monitoring program. Design studies, with field testing on each selected system component, are required to determine the parameters to be measured and to establish monitoring protocols. The best approach to diagnostic monitoring appears to be based on the population dynamics of selected species relative to physical and chemical environmental factors. Both management and monitoring of natural ecosystems need to be recognized as experimental endeavors, and thus approached in an iterative fashion with the scientific method to reduce uncertainty and cost.  相似文献   

9.
模型公式法在确定BOD_5样品稀释系数中的应用   总被引:1,自引:0,他引:1  
本文提出了一种利用以往监测数据计算BOD5稀释系数的简易公式,为BOD5测定中稀释系数的确定提供了一种科学准确的计算方法。本法不受经验因素的限制,并能确保BOD5样品分析的可靠性与成功率,具有应用与推广价值。  相似文献   

10.
The portion-dilution model is a parametric restatement of the conventional view of animal pollination; it predicts the level of pollinator-mediated gene dispersal. In this study, the model was applied to white clover (Trifolium repens) and its most frequent pollinator, the honeybee (Apis mellifera). One of the three parameters in the portion-dilution model is the mean number of flowers a pollinator visits in one foraging bout. An alternative method to estimate this parameter was developed that was not depending on pollinator hive-seeking behaviour. The new estimation method, based on nectar collection, seems to be a good alternative, when reliable observation on visiting behaviour of pollinators is not possible. The gene flow in white clover was modelled. Where fields were assumed to be well separated, and only a low fraction of bees travelled between fields, the gene flow was estimated to be 0.7%, but subjected to large uncertainty. In a worst case scenario with adjacent fields—one with a genetically modified (GM) T. repens cultivar and the other with a conventional T. repens cultivar—and where all arriving bees were expected to transfer GM pollen, the median gene flow was modelled to be 7% with an estimated 95% percentile of 70%. The results show that the European Union threshold limit of 0.9% GM admixture for food and feed will likely be exceeded at times and especially organic farmers that do not accept GM admixture and often have clover and clover–grass fields might face challenges with admixture of GM.  相似文献   

11.
Analysis of covariance (ANCOVA) is a powerful statistical method which incorporates one or more covariates into the analysis to reduce error associated with measurement. ANCOVA (modeling response as a function of fish size) is frequently used to analyze environmental effects monitoring (EEM) fish survey data. In approximately 12% of fish survey data sets taken from cycles 1 to 3 of Environment Canada’s EEM database for pulp and paper mills, the standard assumption of parallel regression slopes is not met. For the first three cycles of the EEM program, these data sets were classified as indicating a mill effect, but for the most part were excluded from subsequent analyses aimed at quantifying the effect. We present two different methods for initially dealing with data sets that exhibit heterogeneous slopes so that they can be analyzed using the parallel slope model. The first method identifies data sets where heterogeneous slopes are forced by a few high-influence observations. The second approach identifies data sets where a model with heterogeneous slopes is statistically, but not practically, significant: with a high coefficient of determination for the parallel slope model. These new methodologies are applied to EEM pulp and paper data sets and about 55% of cases with heterogeneous slopes can be described by a parallel slope model. We also discuss a third method that can be used to describe mill effects when regression slopes remain heterogeneous even after applying the above two methods, enabling comparison with a critical effect size. These new methodologies could benefit the EEM program by enabling more data sets to be incorporated into meta-analyses and be used to make more equitable mill monitoring decisions in the future.  相似文献   

12.
In this paper results concerning project of an atmospheric monitoring network applied to an area of south of Italy carried out using chemical measurement campaigns (for traffic emissions characterisation couple with diffusional simulation of industrial pollutant emissions will be presented. The area selected is characterised by an high concentration of high environmental impacting industrial activities, with also high concentration of urban settlement and vehicular traffic. A comprehensive definition of all the monitoring system to be installed in order to have a correct monitoring system for the all province will be described and discussed.  相似文献   

13.
2011—2021年,熟料产量呈波动上升趋势。水泥行业整体生产运行水平不断提高,熟料单条生产线平均规模由43.8万t/条提升至115.3万t/条,熟料单位产品综合能耗下降14.4%,熟料单位产品CO2排放强度下降6.3%,但CO2排放总量增加了13.8%,与氮氧化物减排趋势形成较大反差,碳污治理水平差距明显。熟料生产中石灰石分解和煤炭燃烧过程的CO2排放合计占比为92.9%~93.8%,是CO2排放的主要来源。由于熟料系数偏高、非碳酸盐原料替代不足、综合能耗仍然较高等原因,安徽等7个熟料产量大的省份的CO2排放强度高于全国。建议实行碳酸盐熟料产量总量控制,逐步降低熟料应用比例,加快建材市场熟料产品和非碳酸盐原料替代,降低高标号水泥使用比例。应大力推广水泥行业节能降耗增效技术,加快熟料落后产能淘汰。对熟料产量大、碳排放强度高的地区,应结合当地碳排放特点,实行差别化降碳策略。各大气污染防治重点区域应因地施策推进水泥行业减污降碳工作。  相似文献   

14.
奎屯市城市污水的处理现阶段采用一级处理后接生物稳定塘的处理工艺是较为适宜的,但要注意做好污水及处理水的排放监测,加强排水管理,今后要逐步完善为规范的二级处理工艺。对污水处理要制定切实可行的水污染防治规划,不拘泥于现有的排水方案和污水处理厂选址,在污水厂下游建设规范的污水库作为处理水资源化利用的必要措施。我区多数城市水污染防治路线与奎屯市有着相似性,对各城市污水处理方式及利用途径可采用此方法进行深入细致的研究论证,为未来城市污水的有效处理及无害化、资源化利用打下基础。  相似文献   

15.
The public and their elected representatives want to see whether they get Value-for-Money from investment in preventing pollution. For many rivers, the achievement of good water quality is a matter of regulating the discharges from wastewater treatment plants. The effective audit of the quality of such discharges is a good basis for measuring progress in controlling pollution. To prove that control is effective, the techniques which underpin the following tasks must be sound and consistent:
  • - the standards for rivers must be devised so that the environmental objectives are met with the required reliability; the form of the standards will be constrained by the procedures available to monitor compliance;
  • - the standards worked out for effluents must have the correct mathematical relation with the river targets, and they too must be consistent with the options available for auditing performance;
  • - the assessment of compliance must be objective; and,
  • - statistics used to summarise the performance of a region (or a Nation) must be simple, stable, clear, and consistent with the results for individual sites.
  •   相似文献   

    16.
    无人监测船在城市内河水质监测中的应用   总被引:1,自引:0,他引:1       下载免费PDF全文
    采用无人船监测技术结合镇江市内河水质状况普查工作,大于120 h的航行试验,总航行里程约为90 km,对建成区水体中的氨氮(NH3-N)、溶解氧(DO)、氧化还原电位(ORP)和浊度进行原位监测,结果表明,通过合理选择搭载相应的测量电极,无人监测船能够满足地表水测量数据准确度的要求,同时可实现研究区域的监测全覆盖,提升了地表水环境监测的工作效率。  相似文献   

    17.
    The study looked at the levels of pesticides in okra grown close to a watermelon farm herein referred to as a non-target crop. The watermelon received some pesticide application in the course of its cultivation, and the okra which was not meant to be sprayed was also affected by the pesticide. About 500 okra samples were collected for a period of 6 weeks and pesticides extracted with 1:1 n-hexane and dichloromethane which was analysed with Agilent 2222 GC/MS coupled with 389 auto-sampler. The results confirmed accumulation of significant levels of pesticides in the non-target crop (okra grown close to watermelon farm). Levels of organochlorine pesticides ranged from 3.10 to 7.60 μg/kg whilst the organophosphorus pesticides had levels ranging from 2.80 to 2016.80 μg/kg. The synthetic pyrethroid pesticide mean levels also ranged from 0.10 to 4.10 μg/kg and were below World Health Organization/Food and Agriculture Organization-recommended residue levels, and though not appearing to constitute a grave threat to life, their occurrence is a concern, and pre-emptive techniques must be developed to thwart the contaminations. Though the non- target crop was not treated directly with the pesticides, some level of contamination with organochlorine and organophosphorus pesticides persisted in the crops. It can be inferred that application of pesticides affected the adjoining crops, meaning that inter-cropping and mix-cropping might not be acceptable when one of the crops requires pesticide application. It is important for the farmers to be trained to ensure proper application of pesticide to minimise its impact on the health of consumers.  相似文献   

    18.
    Conservation planners are called upon to make choices and trade-offs about the preservation of natural areas for the protection of species in the face of development pressures. We addressed the problem of selecting sites for protection over time with the objective of maximizing species representation, with uncertainty about future site development, and with periodic constraints on the number of sites that can be selected. We developed a 0–1, linear optimization model with 2 periods to select the sites that maximize expected species coverage subject to budget constraints. The model is based on the idea that development uncertainty can be characterized by a set of scenarios, each of which is a possible second-period development outcome for the set of sites. We also suggest that our 2-period model can be used in a sequential fashion that is consistent with adaptive planning. Results are presented for the Fox River watershed in Chicago.  相似文献   

    19.
    Conservation planners are called upon to make choices and trade-offs about the preservation of natural areas for the protection of species in the face of development pressures. We addressed the problem of selecting sites for protection over time with the objective of maximizing species representation, with uncertainty about future site development, and with periodic constraints on the number of sites that can be selected. We developed a 0–1, linear optimization model with 2 periods to select the sites that maximize expected species coverage subject to budget constraints. The model is based on the idea that development uncertainty can be characterized by a set of scenarios, each of which is a possible second-period development outcome for the set of sites. We also suggest that our 2-period model can be used in a sequential fashion that is consistent with adaptive planning. Results are presented for the Fox River watershed in Chicago.  相似文献   

    20.
    水质等比例采样器在总量监测中的应用   总被引:1,自引:0,他引:1       下载免费PDF全文
    介绍了水质等比例采样器在总量监测中的应用、配置及其在苏州市的使用试点情况,指出了水质等比例采校器在使用过程中存在着配置不足、对不同类型废水适应性不够、缺乏水样保存措施等问题,提出了环保部门可将水质等比例采样器的使用纳入污染控制管理的范畴,生产厂家应不断完善仪器性能,使用者必须接受专业培训,以及在仪器中设置低温冷藏室、加药系统和多个盛样器等对策。  相似文献   

    设为首页 | 免责声明 | 关于勤云 | 加入收藏

    Copyright©北京勤云科技发展有限公司  京ICP备09084417号