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1.
简单分析了指数评价法、模糊综合评价法和灰色关联分析法的优点和不足之处.在此基础上,本文提出了二次灰色关联分析模型,该模型即能对某环境监测点的环境质量进行综合评价,又能对所有环境监测点的某一环境污染物的污染状况进行综合评价,使评价结果更加完善.同时,该模型也能避免指数评价法、模糊综合评价法和灰色关联分析法的不足之处。  相似文献   

2.
该书结合了环境科学、旅游学、生态学等相关的基础学科知识,参考了国内外大量最新的文献资料及我国环境影响评价法和评价导则,立足于教学和实践工程项目,较为系统地介绍了景区环境影响评价的程序和方法,尤其对动物、植被、环境容量、景观评价作了详细的叙述,旨在为从事环境教育和环境评价工作的学者提供一本教材和参考书。全书共分11章。第一章为概述,主要介绍了景区环境及景区环境影响评价基本概况;第二章~第八章主要介绍了景区环境现状调查和评价方法、影响预测和评价方法(分别为空气、水体、植被、土壤、野生动物、景观和环境容量);第九章为综合评价,  相似文献   

3.
赋权优化层次分析与环境设施性能评价   总被引:2,自引:0,他引:2  
提出了赋权优化层次分析法,并将其应用于污水处理厂的综合性能评价。实例分析表明,该方法具有赋权合理、计算方便、一致性程度高、受决策者主观臆断影响小和评价结果可靠等特点。  相似文献   

4.
模糊指数聚类在环境质量评价中的应用   总被引:2,自引:0,他引:2  
文中以环境污染指数为基础,提出了模糊指数聚类法,并将其应用于环境质量评价之中。实例分析表明,该方法模糊性特征明显,评价结果客观、合理。  相似文献   

5.
大气环境质量评价的属性识别法   总被引:14,自引:0,他引:14  
阐述了评价大气环境质量的属性识别法,介绍了属性识别理论模型和属性权重的确定方法,并根据GB 3095—1996((大气环境质量标准》,分别采用模糊数学综合评价法和属性识别法对武汉市大气环境监测结果进行了实例评价,结果表明,用属性识别法评价的结果比用模糊数学综合评价法评价的结果更能反映真实情况。  相似文献   

6.
提出了“合讲排序法”,运用该方法可以评价出实验室间样品考核排序名次,提高实验室质量控制水平。  相似文献   

7.
将多目标决策中的密切值法,应用于城市环境综合整治定量考核工作的评比。本文叙述了优劣排序原理和评价步骤,实例分析表明该方法结构合理,计算简便,密切值法排序结果与现行采用的评分法相符合。  相似文献   

8.
用密切值法评价沙湾荒漠区生态环境质量   总被引:3,自引:0,他引:3  
利用多目标决策中的密切值法进行沙湾荒漠区生态环境综合评价。该方法简便、适用、且分辨率较高,对各监测点群的定量描述符合实际状况。  相似文献   

9.
基于改进PSR模型的长株潭地区土地生态系统健康评价研究   总被引:1,自引:0,他引:1  
基于改进的PSR模型构建土地生态系统健康评价指标体系,运用组合赋权法确定指标权重,对长株潭地区及其各县(市、区)的土地生态系统健康进行定量分析和评价。研究表明:2002—2014年,长株潭地区土地生态系统健康综合指数由5002下降至4132,呈波动下降趋势,主要影响因素为单位耕地农药施用量、单位耕地化肥施用量、水土流失比率、森林覆盖率、环保投资额占GDP比例、封山育林及当年造林面积。该地区15个县(市、区)的土地生态系统健康状况呈现明显的时空差异,1个属于综合指数快速上升区,6个属于基本稳定区,7个属于慢速下降区,1个属于快速下降区。  相似文献   

10.
环境质量评价方法的优选   总被引:1,自引:0,他引:1  
为了选了最适宜的环境质量评价方法,用密切值法,灰色关联度法和贴近度法分别对同类水质进行评价,结果表明,密切值法适合评价污染较重的水质,它能反同各点位的污染状况对环境质量的影响因素。  相似文献   

11.
Flood spreading is a suitable strategy for controlling and benefiting from floods. Selecting suitable areas for flood spreading and directing the floodwater into permeable formations are amongst the most effective strategies in flood spreading projects. Having combined geographic information systems (GIS) and multi-criteria decision analysis approaches, the present study sought to locate the most suitable areas for flood spreading operation in the Garabaygan Basin of Iran. To this end, the data layers relating to the eight effective factors were prepared in GIS environment. This stage was followed by elimination of the exclusionary areas for flood spreading while determining the potentially suitable ones. Having closely examined the potentially suitable areas using the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) II and analytic hierarchy process (AHP) methods, the land suitability map for flood spreading was produced. The PROMETHEE II and AHP were used for ranking all the alternatives and weighting the criteria involved, respectively. The results of the study showed that most suitable areas for the artificial groundwater recharge are located in Quaternary Qg and Qgsc geologic units and in geomorphological units of pediment and Alluvial fans with slopes not exceeding 3 %. Furthermore, significant correspondence between the produced map and the control areas, where the flood spreading projects were successfully performed, provided further evidence for the acceptable efficiency of the integrated PROMETHEE II-AHP method in locating suitable flood spreading areas.  相似文献   

12.
In order to investigate the metal distribution, speciation, correlation and origin, risk assessment, 86 surface soil samples from the catchment area around the Miyun Reservoir, Beijing, including samples from gold and iron mine areas, were monitored for fractions of heavy metal and total contents. Most of the metal concentrations in the gold and iron mine soil samples exceeded the metal background levels in Beijing. The contents of most elements in the gold mine tailings were noticeably higher than those in the iron mine tailings. Geochemical speciation data of the metals showed that the residual fraction dominated most of the heavy metals in both mines. In both mine areas, Mn had the greatest the acid-soluble fraction (F1) per portion. The high secondary-phase fraction portion of Cd in gold mine samples indicated that there was a direct potential hazard to organisms in the tested areas. Multivariate analysis coupled with the contents of selected metals, showed that Hg, Pb, Cr, and Ni in gold mine areas represented anthropogenic sources; Cd, Pb, and Cr in iron mine areas represented industrial sources. There was moderate to high contamination of a few metals in the gold and iron soil samples, the contamination levels were relatively higher in gold mine than in iron mine soils.  相似文献   

13.
根据南京市5家市政水厂水源保护区的污染源调查结果建立了长江南京段水动力和有限体积法水质数学模型,并结合各污染源的污染强度和排放规律,分析了枯水期在不同水文情况下,污染源排放对饮用水源地水质的影响.有限体积法的模拟结果与常规分析的监测结果均表明,水厂受污染程度为:上元门水厂>北河口水厂>城北水厂>浦口水厂>城南水厂.主要污染源为水量较大,且有一定污染的入江河流.  相似文献   

14.
水源水除藻研究中藻类监测方法的选用   总被引:8,自引:0,他引:8       下载免费PDF全文
对显微计数和叶绿素α测定两种主要藻类的监测方法进行了简要评述,提出在水源水除藻研究中应针对不同的除藻机制,采取不同的藻类监测方法。化学氧化除藻大都使用强氧化剂,将它们投入含藻的水体后,能穿透藻类细胞壁,扩散至细胞内部氧化叶绿素,使藻类代谢终止、死亡,故宜采用叶绿素α法。生物法除藻是利用生物对藻类的吸附、捕食和分解等作用去除藻类,则应采用计数法。  相似文献   

15.
从仪器精密度、方法检出限、准确度、工作曲线线性范围等角度对总有机碳测定仪TOC-5000A(高温燃烧+非分散红外法)与Aurora 1030W(湿式氧化)的性能进行比较.研究结果显示,TOC-5000A方法检出限(0.535ppm)高于Aurora1030W(0.047ppm),且在较低有机碳浓度下(1ppm)精密度差于Aurora 1030W.但在较高有机碳浓度条件下(10ppm),TOC-5000A精密度优于Aurora 1030W.在不同水样中加入标准物质后计算方法回收率,两台仪器的测试结果均大于90%.在样品量较低的情况下,碳加入量与两台仪器响应值的线性关系均较差,响应因子随碳加入量的增加呈现显著降低的趋势,并分别在升至2μg(Aurora 1030W)与0.16μg(TOC-5000A)后达到稳定.  相似文献   

16.
Haloethanoic (haloacetic) acids are formed during chlorination of drinking water and are regulated by the Environmental Protection Agency (EPA). These compounds are normally quantified by gas chromatography with electron capture detection (GC-ECD) as the methyl esters. EPA Method 552 uses diazomethane (CH2N2) for this purpose, but has only been validated by EPA for HAA6: chloro-, dichloro-, bromo-, dibromo-, bromochloro- and trichloroacetic acids. EPA Method 552.2 was developed and validated for all nine analytes (HAA9 = HAA6 + dibromochloro-, bromodichloro- and tribromoethanoic acids). Since the promulgation of Method 552.2, which uses acidic methanol, a debate has ensued over discrepancies observed by various laboratories when using diazomethane instead. In an effort to identify and eliminate potential sources for these discrepancies, a comparative study was undertaken for HAA9. Better accuracy and precision were observed for all HAA9 species by Method 552.2; recoveries were satisfactory in de-ionized and tap water. Method 552 remains satisfactory for HAA6. Systematic differences in instrumental response are observed for the two methods, but these are precise and may be accounted for using similarly treated standards and analyte-fortified (spiked) samples. That notwithstanding, Method 552 (CH2N2) was shown to be unsuitable for dibromochloro-, bromodichloro- and tribromoethanoic acids (HAA9-6). The primary problem appears to be a photoactivated reaction between diazomethane and the HAA9-6 analytes; however, side reactions were found to occur even in the dark. Analyte loss is most pronounced under typical laboratory lighting (white F40 fluorescent lamps + sunlight), but it is also observed under Philips gold F40 lamps (lambda > or = 520 nm), and in the dark.  相似文献   

17.
The vertical flow of water through horizontal layers of soil is considered using the Method of Lines. Continuity of mass principles are used to develop the interface boundary conditions, by introducing fictitious points at the interface, and the boundary conditions are handled using explicit and iterative approximations. Both the pressure based, and the water content based forms of Richards' equation are solved using the Method of Lines. The solutions obtained are compared with some particular analytic solutions obtained from the literature, and the results show that good accuracy can be achieved. It is also shown that the water content model can handle a large discontinuity at the interface when compared against the analytical solution. This result is also confirmed against a numerical example from the literature, and was effective for relatively dry initial conditions.  相似文献   

18.
联合测定水中总磷和总氮   总被引:2,自引:1,他引:2  
《水和废水监测分析方法》(第4版)中,总磷和总氮两项测定都需数小时以上的前处理过程。由于消化条件对测试结果的影响较大,故每次样品测试必须同时做标准曲线。若两个项目分别测定,不仅耗时耗力,又因所采样品保存时间较短,需在24h内测定,一个人同时承担这两个项目有点难于应付。今采用同时消化总磷和总氮,在所有试剂和条件与消化总氮的条件相同的情况下,节省一半的时间和试剂,其结果不论是标准曲线、精密度、准确度均符合质量要求。对提高工作效率具有实际应用意义。  相似文献   

19.
The Low Carbon Development Strategy proposed in June 2009 by the government of Guyana in response to the Reducing Emissions from Deforestation and Forest Degradation in Developing Countries program has triggered evaluation of forest-related activities, thereby acting as a catalyst for improvements in Guyana's small- to medium-scale gold mining industry. This has also shed light on areas committed to conservation, something that has also been handled by Non Governmental Organizations. This paper compares water quality and mercury concentrations in sediment from four main areas in Guyana, two that are heavily mined for gold using mercury amalgamation methods (Arakaka and Mahdia) and two that are considered conservation areas (Iwokrama and Konashen). Fifty-three sediment and soil mercury loadings ranged from 29 to 1,200 ng/g and averaged 215 ± 187 ng/g for all sites with similar averages in conservation and mining areas. Sediment loadings are within the range seen in French Guiana and Suriname, but conservation area samples had higher loadings than the corresponding uncontaminated baselines. Type of ore and location in the mining process seemed to influence mercury loadings. Mercury sediment loadings were slightly positively correlated with pH (correlation coefficient = 0.2; p value < 0.001) whereas no significant correlations were found with dissolved oxygen or turbidity.  相似文献   

20.
We used simple questionnaire surveys to obtain rough categorical information on the status of semiarid and arid rangelands in the Karoo, South Africa. We sent questionnaires to extension officers of the Department of Agricultural Development, asking them to rank the condition of the rangeland in their extension districts (usually about 500 farms) on a three- or five-point scale. The questionnaire also sought information on the possible reasons for changes in the condition of the rangelands; vegetation types most at risk on mismanaged rangelands; and changes in the status of plants, birds, and mammals. Extension officers rated 35% of the semiarid rangelands in southwestern South Africa (the Karoo and southern Kalahari Desert) as being in poor condition. There was some congruency between the perceived condition of the agricultural extension district and the percentage that the stocking rate had decreased. Rangeland condition in more arid areas tends to be poor. Stocking rates have decreased disproportionately more in arid areas than in the more mesic areas of southwestern South Africa. Grasses were rated as the most threatened group of plants, and succulents the least threatened group. Overgrazing in the past was considered to be the most important cause of present-day rangeland condition, followed by present overstocking of rangelands. Antelope were considered more threatened by rangeland management than mammalian carnivores. Avian raptors and bustards, gamebirds, and tortoises were all perceived to be threatened by rangeland mismanagement.  相似文献   

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