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1.
基于模糊综合与可变模糊集耦合的地下水质量评价   总被引:4,自引:0,他引:4  
模糊综合评价法和可变模糊集方法是常用的地下水质量评价方法,但可变模糊集评价法的隶属度计算复杂、可变参数多,而模糊综合评价法容易造成隶属度信息丢失.本文在充分吸取两者优点的基础上,构建了一种新的耦合地下水质量评价模型,优化了评价因子选择、权重确定、模糊算子选择等关键环节,并对青岛市大沽河水源地的地下水质量进行了评价和分析对比.结果表明,水源地中北部(W7~W11)地区,硝酸盐氮含量严重超标,耦合模型得到的水质等级均为4或5类水,评价结果符合该区域实际水质状况,说明新建的耦合模型是可靠的.另外,从监测井W2、W3、W4、W7、W10、W11、W12获得的最大隶属度小于0.5,说明模糊综合评价法不适用于这些点的水质评价,而耦合模型综合考虑了其它隶属度值对评价结果的贡献,其结果更加科学、合理.  相似文献   

2.
通过调查呼和浩特地区地下水潜水环境质量,依据地下水环境标准,建立隶属度矩阵和权重级。运用模糊综合评判法对呼和浩特地区地下水潜水质量进行评价,并对模糊综合评价法和综合指数法的评价结果进行比较分析。  相似文献   

3.
在地下水质量标准中,各指标权重的选择与权重的内涵存在着不确定性;同一指标的分级界点值差异显著,近似地呈现几何级数变化。基于以上这两种情况,构建基于指标模糊权和协调性下的地下水水质评价模型。应用层次分析法和专家调查9标度法确定指标的相对权重,结合贝塔系数计算出指标的模糊权重。对评价标准及待评价地下水水质监测值进行对数变换,采用距离测度法来构造隶属函数,并对其进行求余,按最大隶属原则来评判地下水质量等级。应用此模型对徐州市的重要水源地——张集地下水水质进行评价。结果表明:研究区的20个采样点水质为Ⅱ、Ⅲ级的占90%,符合饮用水的要求。与投影寻踪法的评价结果基本一致。  相似文献   

4.
介绍了传统评分法的基本计算步骤,在此基础上,运用评分法对大连市五区地下水质量进行了系统的评价,以此指导大连市区地下水开采方案的设计和地下水资源的规划与管理.  相似文献   

5.
将人体健康作为风险因素之一的地下水污染风险评价模型,其风险路径分析过程表现模糊,为了能够解决这一问题。该文建立了VCH(Vulnerability&Capacity&Health)地下水污染风险模型,其特点表现在包含了地下水脆弱性评价、地下水环境容量评价和地下水健康风险评价且模型风险路径计算过程清晰。为了验证该文提出的VCH模型的合理性,该文以富平热电厂厂址附近的水文地质资料为基础,采用该模型风险计算方法评价研究区的地下水污染风险。结果表明:研究区地下水污染风险等级整体处在较低风险等级以下,且处于较低风险等级面积占研究区总面积的79.01%,而中等风险仅占3.67%,研究区其余部分均为低风险,该次地下水污染风险评价结果为研究区地下水污染防治及地下水规划利用提供依据。另外,该模型为区域地下水污染风险评价提供了借鉴方法。  相似文献   

6.
地下水水质评价是地下水污染防控和水环境管理的基础.不同评价方法会得到不同的评价结果,因此如何选择合适的评价方法至关重要.目前,缺乏科学、客观的地下水水质评价方法筛选技术.基于此,以洛阳市为例,采用内梅罗指数法、模糊综合评价法和基于免疫进化算法优化的普适法(简称"普适法")3种方法开展地下水水质评价,通过建立级别差方法,定量筛选最适用评价方法.结果表明:①模糊综合评价法-内梅罗指数法、普适法-模糊综合评价法、普适法-内梅罗指数法3种统计方法计算得到的级别差小于0的比例占比分别为34.62%、19.24%和46.16%,大于0的占比分别为19.23%、23.07%和26.92%,因此模糊综合评价法评价得到的地下水水质级别 < 普适法评价得到的地下水水质级别 < 内梅罗指数法评价得到的地下水水质级别.②模糊综合评价法最适用于研究区地下水水质现状评价,采用该方法评价得到研究区地下水水质分为优良(Ⅰ类)、良好(Ⅱ类)、较好(Ⅲ类)、较差(Ⅳ类)和极差(Ⅴ类)5类(参照GB/T 14848-2018《地下水质量标准》),以良好和较好水质为主,造成地下水水质较差的组分主要为CODMn、总硬度、硝酸盐和汞.研究显示,级别差法可作为定量的地下水水质评价方法筛选技术,能够为地下水水质评价研究提供新的思路.   相似文献   

7.
本文将模糊综合测度指数模型应用于北海市地下水质量评价,并用我们开发的“环境质量评价系统”软件演示了实例评价过程,使得本法应用更为快捷,评价结果更加合理。  相似文献   

8.
集对分析法在大气环境质量评价中的应用   总被引:2,自引:0,他引:2  
在集对分析原理的基础上,建立集对分析方法评价大气环境质量的新模型。通过实例研究,与模糊综合评判法、属性识别法以及改性属性识别法比较,集对分析方法评价模型严谨,计算简便,评价结果更合理、精细、稳定,为大气环境质量综合评价提供了一种简单而适用的评价方法。  相似文献   

9.
不同的水质评价方法有不同的适应性,为准确评测昆明市宜良县地下水水质,以2015年宜良县10个主要监测井的监测数据为基础,选取硫酸盐、硝酸盐氮等6个水质评价因子,分别采用传统、改进内梅罗污染指数法、加附注评分法和主成分分析法进行水质评价。研究结果表明:传统内梅罗指数法评价效果较差;改进内梅罗指数法仅适用于掌握水体的污染程度;主成分分析法适用评价指标过多的情况,通过降维对其简化,最大限度保留原始信息;加附注评分法在评价过程中将全部指标纳入模型计算,评价结果拟合度高、适应性、稳定性好,评价更为科学客观,最适合用于研究区地下水评价。  相似文献   

10.
应用模糊评价法对福建闽江河口湿地土壤环境质量进行评价,在模糊算子的选择上采用加权平均模型,评价研究表明:加权平均模型充分考虑了每个因子的影响,评价结果更客观。  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

13.
Several main metabolites of benzo[a]pyrene (BaP) formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone (BP 1,6- quinone), trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-diol), 3-hydroxybenzo[a]pyrene (3-OHBP), were identified by high-performance liquid chromatography (HPLC). The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that (1) the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; (2) the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; (3) the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% (w/v), concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.  相似文献   

14.
Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.  相似文献   

15.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

16.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.  相似文献   

17.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

18.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.  相似文献   

19.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.  相似文献   

20.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

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