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1.
在物元分析的基础上,引入各监测断面到其所在类别的重心距离,构建了一种定量的监测断面优化方法。以2009年1月—2010年12月辽河干流水环境监测数据为基础,对辽河干流水质监测断面进行优化,并采用T检验、F检验和相邻断面监测数据相关性对优化结果验证。结果表明,使用改进的物元分析法优化后,辽河干流监测断面减少为6个,监测效率提高了25%。在优化后的监测断面与在原监测断面监测获得的数据均值无显著差异、方差齐,而且经过优化后的断面重复布设情况得到显著改善,水质监测断面合理性显著增强。  相似文献   

2.
科学合理地布设水质监测断面是全面准确获取水环境质量监测数据的前提条件。利用研究区域现有断面2014年的监测数据,结合水资源调度方式和水环境功能区划要求,划分为五大片区并采用聚类分析方法进行断面优化,通过F检验和t检验表明优化前后断面无显著差异。同时,提出了一种综合的水环境质量考核办法——区域水环境综合评价考核指标,该指标包括骨干河道、乡村河道两类考核断面,采用综合水质评价与单因子评价相结合的方法,设置适当的权重系数,评价结果较为全面、客观地反映区域水环境质量状况,基本满足对区域水环境质量考核评价的管理需求。  相似文献   

3.
辽河水体主要污染指标时空异质性分析   总被引:2,自引:0,他引:2  
利用1987~2009年辽河干流8个常规监测断面的历年监测数据,通过统计分析确定辽河水质的主要污染指标为化学需氧量(COD)和氨氮,2007年前辽河水质首要污染指标是COD,2008年和2009年氨氮超过COD成为辽河水质污染首要污染指标;分析干流两项指标的时间、水期、空间分布规律,明确给出水质污染重点治理时段和河段.  相似文献   

4.
基于2018年-2019年松江池塘循环流水养殖模式水质监测数据,采用物元分析和聚类分析相融合的评价方法对水环境质量状况进行评价.结果表明,改进后的物元分析适用于池塘循环流水养殖模式监测网络,监测点从19个减少到8个,可节省50%的成本.F检验和T检验验证结果表明,优化后的监测网络能较好地代表原始监测网络.  相似文献   

5.
利用较少的监测断面,花费较少的人力、物力、财力,取得能够反映具有代表性的水环境质量数据,是监测断面优化的主要目的。通过对监测断面优化的研究,能够为环境监测、管理、河流污染治理、网络的建设提供科学依据。本优化调整的原则主要是在原有监测断面的基础上,考虑水文特征、  相似文献   

6.
为了了解长江干流平水期同一时间不同空间的水环境质量状况,确定各种水污染物浓度沿程变化情况,为长江干流污染物排放总量控制行动计划提供依据,并通过水样陈列展示三峡大坝截流前各江段水样表观状况,国家环保局于1996年5月7日组织长江暨三峡生态环境监测网33个成员站在上自攀枝花下至上海的长江干流设立35个监测断面进行了首次水质同步监测,取得了圆满成功。通过对近万个监测数据的分析表明,长江干流各江段整体水质状况尚好,40%的江段属二类水域,除个别断面水质有中度污染外,大部分江段  相似文献   

7.
辽河流域水环境监测网络优化技术研究   总被引:1,自引:1,他引:0  
以辽河流域2009—2011年监测数据为基础,针对北方季节性河流,在制定了水环境监测网络优化原则的前提下,分别运用最优分割法、变异系数与水质类别相结合方法、连续3年未检出判断法进行了辽河流域水环境质量监测断面、监测频次和监测项目的优化。结果表明,辽河流域优化后的监测断面为18个,比优化前减少8个。在监测频次上,干旱少雨的月份中,1、5、10月应保持每个月2次的监测频次,2—4月、11—12月每月监测1次;湿润多雨的6—9月只监测1~2次即可,全年监测频次分布更合理。监测项目分为必测项目和选测项目,必测项目为12~20项,选测项目为3~11项。  相似文献   

8.
动态贴近度法在徒骇河干流水质监测点优化中的应用   总被引:1,自引:0,他引:1  
根据2010—2012年的COD、BOD5、NH3-N、TP和Cr6+的例行监测数据,采用动态贴近度法,对徒骇河干流13个监测点进行优化。分别计算丰水期、平水期和枯水期的最优点和最劣点的距离,从而计算出最优贴近度值。利用t检验和F检验对优化结果进行准确度和精确度检验,结果表明,优化后的8个监测点的监测数据可以代表整个干流的水质状况。  相似文献   

9.
泰山区水环境监测网络优化研究   总被引:1,自引:1,他引:0  
对泰山区目前水环境监测网络系统进行了综合分析评价 ,采用专家权重评估、物元分析方法对原监测断面进行了优化研究 ,在此基础上建立起新型监测网络的地理信息系统  相似文献   

10.
关于建立区域水环境质量监测网络定期优化机制的思考   总被引:2,自引:2,他引:0  
水环境质量监测网络是水环境风险监控体系的重要基础。随着社会经济结构发生改变,河流的水文情况、纳污状况及水功能区划发生了很大变化,现有的监控断面很难满足管理的需求。以河北省为例,提出了区域性地表水环境监测网络存在覆盖面严重不足、监测资源浪费、调整不系统、信息不完整等问题,阐述了定期优化全流域水环境质量监测网络是保证监测网络代表性,提高网络综合利用率等的重要手段之一。  相似文献   

11.
介绍了世界上一些发达国家的空气污染预报的做法和采取的措施,阐述了我国开展空气质量预报的方针和方法,指出了周报是预报的基础工作。叙述了我国空气质量周报的污染参数的选取、污染指数的分级及其浓度限值和污染指数计算及确定,分析并总结了开展城市空气质量周报所发挥的效用是提高公众的环保意识,加大了治理污染的力度,转变了环境监测的职能,促进了环境监测事业的发展  相似文献   

12.
锅炉烟尘测试中锅炉负荷率的计算方法探讨   总被引:1,自引:1,他引:0  
GB5468 -91规定 ,锅炉烟尘测试时 ,必须对锅炉的运行负荷进行测试 ,而实际监测过程中 ,许多锅炉房不具备测试的计量条件 ,为了解决这一问题 ,文章提出利用烟气量和空气过剩系数计算锅炉负荷率。在实际监测工作中 ,该方法方便、易于操作 ,所得结果和标准规定方法所得结果有很好的一致性  相似文献   

13.
水中总硬度测量不确定度的评定   总被引:5,自引:1,他引:4  
采用EDTA滴定法测定水质总硬度的测量不确定度评定。充分考虑测量重复性、标准溶液的配制、滴定等过程对测量的影响,计算水中总硬度的测量相对合成标准不确定度为1·81×10-3。  相似文献   

14.
“湖泛”恶臭物质分析及来源浅析   总被引:4,自引:0,他引:4  
介绍了中国南方"湖泛"中的恶臭物质及检测情况,采用常规分析和气相色谱-质谱(GC-MS)对"湖泛"水样进行检测,认为"湖泛"恶臭物主要是氨和硫醚类物质。根据"湖泛"发生的时间及频次,结合南方地区农业水稻秧田的农药使用情况,推断氨基甲酸酯类农药的使用可能是"湖泛"发生的诱因。  相似文献   

15.
Chemical weathering is one of the major geochemical processes that control the mobilization of heavy metals. The present study provides the first report on heavy metal fractionation in sediments (8–156 m) of Lake Titicaca (3,820 m a.s.l.), which is shared by the Republic of Peru and the Plurinational State of Bolivia. Both contents of total Cu, Fe, Ni, Co, Mn, Cd, Pb, and Zn and also the fractionation of these heavy metals associated with four different fractions have been determined following the BCR scheme. The principal component analysis suggests that Co, Ni, and Cd can be attributed to natural sources related to the mineralized geological formations. Moreover, the sources of Cu, Fe, and Mn are effluents and wastes generated from mining activities, while Pb and Zn also suggest that their common source is associated to mining activities. According to the Risk Assessment Code, there is a moderate to high risk related to Zn, Pb, Cd, Mn, Co, and Ni mobilization and/or remobilization from the bottom sediment to the water column. Furthermore, the Geoaccumulation Index and the Enrichment Factor reveal that Zn, Pb, and Cd are enriched in the sediments. The results suggest that the effluents from various traditional mining waste sites in both countries are the main source of heavy metal contamination in the sediments of Lake Titicaca.  相似文献   

16.
实验室质量管理体系内部审核的实施   总被引:3,自引:0,他引:3  
在实施GB/T15481-2000 idt ISO/IEC17025:1999标准《检测和校准实验室能力的通用要求》的过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核实施阶段的关键环节,提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法,对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。  相似文献   

17.
贵州黔东南州三板溪水库春季拟多甲藻水华特征   总被引:2,自引:0,他引:2  
2011年3月13日对贵州省黔东南州三板溪水库进行春季浮游植物调查的结果表明,三板溪水库Ⅱ号采样点(下革东)发生以佩纳形拟多甲藻为优势种的拟多甲藻水华,细胞密度高达1.15×107cell/L;板溪水库总氮的最低值为2.09 mg/L,总磷的最低值为0.95 mg/L,三板溪水库的总氮、总磷含量较丰富,不存在总氮或总磷是限制性因子;通过SPSS16.0统计软件分别进行Pearson 积距相关系数分析表明,氮磷比是三板溪水库发生拟多甲藻水华的主要影响原因。  相似文献   

18.
This study was carried out in response to suggestions that the measurement of NO(2) by Palmes-type passive diffusion tubes (PDT) is affected by the method of preparation of the triethanolamine (TEA) absorbent coating on the grids. The following combinations of factors were investigated: TEA solvent (acetone or water), volume composition of TEA in solvent (50% or 20%), and grid coating method (dipping in solution prior to assembly or pipetting solution on after assembly). Duplicate PDTs prepared by each of the 8 methods were exposed in parallel, in urban air, for a total of 80 separate 1 week exposures. NO(2) concentrations derived from PDTs prepared by pipetting methods were significantly less precise than concentrations from dipping methods, with mean RSDs for duplicate measurements of 13.8% and 8.5%, respectively (n= 316 each category). Pipetting methods using solutions of 50% TEA composition were particularly imprecise (mean RSD 17.2%). Data from PDTs prepared by pipetting methods were systematically more poorly correlated with each other and with data from co-located chemiluminescence analysers, than corresponding data from PDTs prepared by dipping methods, indicating that more consistent accuracy was also obtained by the latter PDTs. The statistical evidence suggested that PDTs prepared by pipetting 50% TEA in water generally gave lower NO(2) concentrations. Although this is in agreement with a previous study, it is also possible that such an observation here may be a statistical artefact given the demonstrably poorer precision of this method. The general tendency of PDTs to show positive bias in NO(2) measurement in urban air in 1 week exposures was again evident in this study (mean biases at roadside and urban centre locations of +35% (n= 475) and +18% (n= 112), respectively) consistent with augmentation of within-tube NO(2) flux by chemical reaction between co-diffusing NO and O(3). Overall, it is recommended that the pipetting method of PDT grid preparation is avoided, or at least investigated further, because of the apparent degradation in precision and accuracy of NO(2) measurement. Potential reasons for the effect are discussed.  相似文献   

19.
Substantial amounts of NOx (146 000 t/y) and total hydrocarbons (294 000 t/y) are released to the marine atmosphere by the large number of oil and gas operations over Federal waters of the Gulf of Mexico (GOM). Under appropriate meteorological conditions these emissions react to form ozone (0–54 g/m3 over-water) which can affect the marine environment. Using a dry deposition model, this work examines the amount of ozone derived from oil and gas offshore operations and deposited in the sea surface of the Gulf of Mexico, and assesses its impact on the neuston of the sea-surface microlayer. Surface integrated estimates of ozone deposited from oil and gas operations over the sea surface ranges from 400 kg to 1800 kg which results in sea surface concentrations of 15 g/m3. This estimate and the actual toxic ozone levels suggest no acute, toxic impacts to the neuston. However, indirect effects may occur through changes to the pelagic foodwebs and organic carbon pathways. Another potential pathway for ozone impacting the environment is through the production of bromate. Based on the concentrations and time scales (11–139 days) only sublethal effects appear to occur, but uncertainties associated with this assessment need to be further studied. From an ecological perspective, the environmental impacts and risks of NOx and VOC discharges from offshore platforms need to be assessed for neuston and other components of the marine ecosystem.  相似文献   

20.
污染源监测报告有效期问题的探讨   总被引:1,自引:1,他引:0  
环境监测是环境管理的基础性工作,污染源监测报告(数据)的有效性是保证环境执法严肃、公正的重要条件,也是是守法企业展示良好社会形象的基本保证。依照国家的相关规定,并结合行业技术规范的要求,探讨污染源监测报告的有效期问题,以利于相关各方严肃、科学、合理地使用污染源监测数据。  相似文献   

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