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1.
提出一种基于动态RBF神经网络的地下水质综合评价方法。该方法采用最近邻聚类算法,构建动态RBF神经网络,利用神经网络对待测水质进行分类识别,根据网络输出,实现水质等级的确定。应用结果表明,该方法具有训练速度快、评价准确度高的优点,提高了水质综合评价的精度和客观性。  相似文献   

2.
基于模糊权物元理论的地下水水质评价模型构建及应用   总被引:6,自引:1,他引:5  
在物元分析的基础上,结合模糊权重理论与层次分析方法,构建用于评价地下水水质的模糊权物元分析模型。应用此模型对徐州市的重要水源地——张集水源地的地下水水质进行了综合评价。选取数据较为完整的20个监测井的监测数据进行评价。结果表明,研究区的20个采样点水质为Ⅱ、Ⅲ级的占95%,绝大多数地下水水质较好,符合饮用水的要求。与投影寻踪法和模糊概率法的评价结果比较发现,得出的评价结果与以上2种评价结果基本一致。  相似文献   

3.
通过咨询有关专家,并采用模糊贴近度方法,对专家意见进行统计处理、归纳和综合,建立了小草浆厂蒸煮废液治理工程实践效果评价的指标体系,从而为小草浆厂蒸煮废液治理工程实践效果的综合评价打下了重要基础。  相似文献   

4.
饮食业油烟净化技术综合评价   总被引:1,自引:1,他引:1  
本文首先通过专家调查的方法建立了饮食业油烟净化技术综合评价指标体系,并确定相应的权数,然后采用模糊决策分析方法对现有净化技术进行了分析评价,结果表明,复合式和静电式技术是现有各种技术中最好的。  相似文献   

5.
畜禽养殖污染防治典型工程的综合效益评价   总被引:2,自引:0,他引:2  
通过对我国畜禽养殖污染防治工程建设现状的调查和分析,拟定了我国畜禽养殖污染防治工程的评价指标体系,采用层次分析与灰色关联度分析相结合的综合评价方法,对国内的8个典型工程的综合效益进行了评价。评价结果表明,规模化及综合性的养殖污染防治工程可获得较好的综合效益,而在养殖污染防治中采用单一的沼气化处理,由于其经济性较差,目前尚不能获得较好的综合效益。  相似文献   

6.
土壤环境质量综合评价指标体系是识别土壤环境污染、指导土壤环境管理及开发利用的有效工具。在土壤环境质量评价方法和国内外标准分析的基础上,提出了建立土壤环境质量综合评价指标体系的基本框架;结合"压力-状态-响应"模型(PSR模型),考虑不同工业区特征污染物,建立了包含通用指标和备选指标的土壤环境质量综合评价指标体系。以此评价指标体系为导向,为指导不同类型工业集聚区科学发展提出了工业区周边土壤环境质量分区管理的对策建议。  相似文献   

7.
由于航空工业的特殊性,航空企业节能减排相对滞后,节能减排工作迫在眉睫.为使航空工业节能减排的方案全面、科学、客观,基于现代风险评价方法,根据中国航空企业系统的客观实际,采用模糊综合评价法建立了航空企业节能减排的评价指标体系和评价方法,并确定了该评价指标体系中各指标的权重,进而得到各指标隶属度、模糊矩阵.同时,进行了实例...  相似文献   

8.
本文首先通过专家调查的方法建立了饮食业油烟净化技术综合评价指标体系,并确定相应的权数,然后采用模糊决策分析方法对现有净化技术进行了分析评价。结果表明,复合式和静电式技术是现有各种技术中最好的。  相似文献   

9.
根据《地表水环境质量标准》(GB 3838—2002)中水质指标分类控制要求,对其中的基本项目采用灰色关联加权法,对水源地补充、特定项目应用单因子评价法,由此提出一种水源地水质污染变化特征综合分析的新方法,并以贵州省盘县白河沟水库饮用水源地2005、2008、2011、2013年水质监测数据进行综合评价和污染变化特征实证分析。采用分类别法评价的结果表明:2005—2013年,白河沟水库基本项目所有监测因子和超标因子均表现为水质持续提高的趋势;2005、2008、2011、2013年所有监测因子的水质综合评价结果分别处于GB 3838—2002的Ⅱ、Ⅱ、Ⅱ和Ⅰ类,超标因子分别处于Ⅴ、Ⅳ、Ⅳ和Ⅲ类;水源地补充、特定项目中,硝酸盐氮、铁、锰污染经治理后达标,而苯并芘超标2.5~1.0×10~3倍,仍然是白河沟水库的污染特征因子。  相似文献   

10.
为正确地判断哈尔滨市地下水水质现状及变化趋势,对研究区地下水脆弱性进行研究。根据研究区水文地质背景条件,选取地下水水位埋深、含水层介质、地形坡度、上覆地层介质、单井涌水量5个参数作为评价因子,利用DRASTIC模型对哈尔滨市地下水脆弱性进行评价,并结合MapGIS实现了地下水环境脆弱性分区。结果表明,地下水脆弱性指数为77~123。其中,松花江及阿什河河漫滩是全市地下水脆弱性最高的区域(指数为108~123),地下水极易受污染;一级阶地区、江北水产养殖场及研究区东北部属于中等脆弱区(指数为93~108);中南部岗阜状高平原区属于低脆弱性地区(指数为77~93),受污染风险较小。研究结果能客观地反映区域内的地下水防护性能,有效地为规划部门及地下水资源管理部门提供指导。  相似文献   

11.
A groundwater vulnerability and risk mapping assessment, based on a source-pathway-receptor approach, is presented for an urban coastal aquifer in northeastern Brazil. A modified version of the DRASTIC methodology was used to map the intrinsic and specific groundwater vulnerability of a 292 km(2) study area. A fuzzy hierarchy methodology was adopted to evaluate the potential contaminant source index, including diffuse and point sources. Numerical modeling was performed for delineation of well capture zones, using MODFLOW and MODPATH. The integration of these elements provided the mechanism to assess groundwater pollution risks and identify areas that must be prioritized in terms of groundwater monitoring and restriction on use. A groundwater quality index based on nitrate and chloride concentrations was calculated, which had a positive correlation with the specific vulnerability index.  相似文献   

12.

An appraisal of seawater intrusion into the coastal aquifers is one of the major issues for groundwater resource management. The GALDIT model applies to the analysis of multiple parameters using systematic GIS techniques for mapping and assessment of seawater intrusion vulnerability. It demarcates the mapping of potential vulnerability that shows a higher vulnerability to seawater intrusion in various parts of the coast and the estimated vulnerability index value of 7.50 and 9.64. An area of 33.0 km2 spread in the low-lying coastal area comprising estuaries, salt marshes, and saltpans shows the high vulnerability condition with an estimated vulnerability value of 6.42–7.50. An area of 73.20 km2 spread over coastal and alluvial plains experiences moderate vulnerability (temporal salinity in the groundwater sources) with an estimated vulnerability index value of 5.46–6.42. Aquifers underlying coastal uplands (hard rock formations) and some parts of accretionary beaches (2.05 km2) are relatively protected fresh groundwater sources, wherein the estimated vulnerability index is 4.55–5.46. The vulnerability mapping of the GALDIT model using hydrochemical analysis of primary groundwater parameters such as TDS, Cl?, HCO3, and Cl?/HCO3 ratio is validated. Higher concentration of TDS (2637–4162 mg/l) and Cl? (1268–2347 mg/l) is taken for the areas falling under higher vulnerability to seawater intrusion, especially in the placer mining sites and coastal areas facing erosion. Similarly, the groundwater sources of the low-lying areas including estuaries, salt marshes, saltpans, and backwater were noted to have higher values of Cl?/HCO3 with a rationality of 9.87–12.18. Hydrological facies shows the highest concentration of NaCl in the groundwater sources within the proximity of eroded beaches, saltwater bodies, and sand mining areas. A hydrochemical facies evolution (HFE) diagram represents the hydrochemical facies of groundwater elements that shows an intrusion of seawater into the coastal aquifers underlying the very high vulnerable zones. Higher bicarbonate concentration (233–318 mg/l) is noticed in the upland areas and some parts of dunes and accreted beaches, sandy coasts, and uplands. Vulnerability analysis reveals that those areas near saltwater bodies and eroding coasts are prone to lateral and vertical diffusion of saltwater. The geodatabase developed through such modeling studies can help in planning and developing activities for sustainable groundwater resource management in coastal areas.

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13.
The assessment of aquifer vulnerability is a very important task, especially in agricultural areas because the quality and availability of groundwater affects both the sustainability of agriculture and the quality of life. In this study, an integrated approach is considered, with the use of the generic and agricultural DRASTIC models as well as a geographic information system (GIS), to assess groundwater vulnerability in the agricultural area of Barrax, in the province of Albacete, in Spain. Seven parameters—depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone media, and hydraulic conductivity of the aquifer (DRASTIC)—have been considered as weighted layers to enable an accurate groundwater risk mapping. The results of the generic DRASTIC model indicated very low vulnerability to contamination for Barrax groundwater due to limited urban and industrial development in the wider area. However, agricultural activities impose pressure to groundwater resources and the results of the agricultural DRASTIC model show that 6.86% of the study area is characterized by very high, 2.29% by high, 47.28% by medium, 38.28% by low, and the remaining 5.29% by no vulnerability to groundwater contamination. The distribution of nitrate concentration in groundwater in the area under study is quite well correlated with the agricultural DRASTIC vulnerability index. Sensitivity analysis was also performed to acknowledge statistical uncertainty in the estimation of each parameter used, to assess its impact, and thus to identify the most critical parameters that require further investigation. Depth to water and impact of vadose zone are the parameters that had the most noticeable impact on the generic DRASTIC vulnerability index followed by the soil media and topography. In contrast, the agricultural DRASTIC method is more sensitive to the removal of the depth to water parameter followed by the topography and the soil media parameters.  相似文献   

14.
Environmental Science and Pollution Research - Hybrid and integrated techniques can be used to investigate intrinsic uncertainties of the overlay and index groundwater vulnerability assessment...  相似文献   

15.
This work aims at evaluating spatial distribution patterns of concentration variations for chlorinated solvents in groundwater, based on principal component analysis and geographic information system (GIS) tools. The study investigates long-time series of chlorinated solvent concentrations in groundwater measured for 18 contaminated industrial sites. The characterization of contaminant plumes and delineation of pollutant sources are essential for choosing appropriate monitoring and remediation strategies, as contaminated groundwaters are characterized by complex patterns of spatial and temporal concentration variability, with wide unpredictable fluctuations over time. The present work describes the results of a new exploratory statistical method called the Variability Index Method (VIM) applied to environmental data to assess the performance of using concentration variations as molecular tracers to reveal aquifer dynamics, industrial impacts, and point sources for contamination plumes. The application of this method provides a useful assessment of controls over contaminant concentration variations as well as support for remediation techniques.  相似文献   

16.
桂烈勇 《污染防治技术》2007,20(1):63-66,80
根据太仓市饮用水地表水源和地下水的监测数据,分别采用单因子评价和综合评价方法,对饮用水源的水质进行评价。结果认为地表水水源已受到轻度污染,属Ⅲ类水;地下水的水质较差,已不适合于直接饮用。饮用水水源的主要污染物为COD、氨氮、挥发酚、硝酸盐氮和高锰酸盐指数。对饮用水水源的污染成因进行了全面分析,并从四个方面提出了水源安全保护对策:法律法规与行政手段、技术支撑、经济支持和宣传教育.  相似文献   

17.
Contaminated sites pose a significant threat to groundwater resources worldwide. Due to limited available resources a risk-based prioritisation of the remediation efforts is essential. Existing risk assessment tools are unsuitable for this purpose, because they consider each contaminated site separately and on a local scale, which makes it difficult to compare the impact from different sites. Hence a modelling tool for risk assessment of contaminated sites on the catchment scale has been developed. The CatchRisk screening tool evaluates the risk associated with each site in terms of its ability to contaminate abstracted groundwater in the catchment. The tool considers both the local scale and the catchment scale. At the local scale, a flexible, site specific leaching model that can be adjusted to the actual data availability is used to estimate the mass flux over time from identified sites. At the catchment scale, a transport model that utilises the source flux and a groundwater model covering the catchment is used to estimate the transient impact on the supply well. The CatchRisk model was tested on a groundwater catchment for a waterworks north of Copenhagen, Denmark. Even though data scarcity limited the application of the model, the sites that most likely caused the observed contamination at the waterworks were identified. The method was found to be valuable as a basis for prioritising point sources according to their impact on groundwater quality. The tool can also be used as a framework for testing hypotheses on the origin of contamination in the catchment and for identification of unknown contaminant sources.  相似文献   

18.

The hydrogeochemical processes and fuzzy GIS techniques were used to evaluate the groundwater quality in the Yeonjegu district of Busan Metropolitan City, Korea. The highest concentrations of major ions were mainly related to the local geology. The seawater intrusion into the river water and municipal contaminants were secondary contamination sources of groundwater in the study area. Factor analysis represented the contamination sources of the mineral dissolution of the host rocks and domestic influences. The Gibbs plot exhibited that the major ions were derived from the rock weathering condition. Piper’s trilinear diagram showed that the groundwater quality was classified into five types of CaHCO3, NaHCO3, NaCl, CaCl2, and CaSO4 types in that order. The ionic relationship and the saturation mineral index of the ions indicated that the evaporation, dissolution, and precipitation processes controlled the groundwater chemistry. The fuzzy GIS map showed that highly contaminated groundwater occurred in the northeastern and the central parts and that the groundwater of medium quality appeared in most parts of the study area. It suggested that the groundwater quality of the study area was influenced by local geology, seawater intrusion, and municipal contaminants. This research clearly demonstrated that the geochemical analyses and fuzzy GIS method were very useful to identify the contaminant sources and the location of good groundwater quality.

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19.
Deterioration in groundwater quality has attracted wide social interest in China. In this study, groundwater quality was monitored during December 2014 at 115 sites in the Hutuo River alluvial-pluvial fan region of northern China. Results showed that 21.7% of NO3 ? and 51.3% of total hardness samples exceeded grade III of the national quality standards for Chinese groundwater. In addition, results of gray relationship analysis (GRA) show that 64.3, 10.4, 21.7, and 3.6% of samples were within the I, II, IV, and V grades of groundwater in the Hutuo River region, respectively. The poor water quality in the study region is due to intense anthropogenic activities as well as aquifer vulnerability to contamination. Results of principal component analysis (PCA) revealed three major factors: (1) domestic wastewater and agricultural runoff pollution (anthropogenic activities), (2) water-rock interactions (natural processes), and (3) industrial wastewater pollution (anthropogenic activities). Using PCA and absolute principal component scores-multivariate linear regression (APCS-MLR), results show that domestic wastewater and agricultural runoff are the main sources of groundwater pollution in the Hutuo River alluvial-pluvial fan area. Thus, the most appropriate methods to prevent groundwater quality degradation are to improve capacities for wastewater treatment and to optimize fertilization strategies.  相似文献   

20.
With the development of economy, most of Chinese cities are at the stage of rapid urbanization in recent years, which has caused many environmental problems, especially the serious deterioration of water quality. Therefore, the research of the relationship between urbanization and water quality has important theoretical and practical significance, and it is also the main restriction factor in the urbanization advancement. In this work, we investigated the impact of urbanization on the water quality of the nearby river. We established a comprehensive environmental assessment framework by combining urbanization and water quality, and one model was designed to examine the impact of urbanization on the water quality in Jinan from 2001 to 2010 with factor component analysis. The assessment of urbanization level was accomplished using a comprehensive index system, which was based on four aspects: demographic urbanization, economic urbanization, land urbanization, and social urbanization. In addition, synthetic pollution index method was utilized to assess the water pollution of Xiaoqing River in the study area. Through the analysis of regression curves, we conclude that (1) when the urbanization level is below 25 %, the relationship is low and irregular; (2) if the urbanization level varies between 25 and 40 %, there will be an irreversible degradation of stream water quality; (3) there is a positive correlation between urbanization and pollution levels of urban river after the adjustment period; and (4) land and demographic aspects have the highest independent contribution. This study is a useful reference for policymakers in terms of economic and environmental management.  相似文献   

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