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1.
为支撑国家地下水环境管理与污染防治,在系统梳理我国地下水环境监测发展历程的基础上,分析了当前地下水环境监测的技术特点,从支撑国家地下水环境质量考核的角度出发,研究构建了涵盖点位布设、监测指标选取、样品采集与保存、样品分析测试、质量保证与质量控制、质量评价等全流程的监测技术体系和质量管理体系,建立了"十四五"国家地下水环境质量考核监测网络建设及业务运行模式。基于覆盖全国所有地级及以上城市、主要水文地质单元、典型规模以上地下水型饮用水水源地与重点污染源的考核监测网络,建立了完善的地下水环境监测技术与质量管理体系,有效支撑了国家地下水环境质量考核,有助于各级管理部门掌握地下水环境质量状况,有针对性地开展地下水污染防治,为逐步改善地下水环境质量提供基础保障。  相似文献   

2.
Deplorable quality of groundwater arising from saltwater intrusion, natural leaching and anthropogenic activities is one of the major concerns for the society. Assessment of groundwater quality is, therefore, a primary objective of scientific research. Here, we propose an artificial neural network-based method set in a Bayesian neural network (BNN) framework and employ it to assess groundwater quality. The approach is based on analyzing 36 water samples and inverting up to 85 Schlumberger vertical electrical sounding data. We constructed a priori model by suitably parameterizing geochemical and geophysical data collected from the western part of India. The posterior model (post-inversion) was estimated using the BNN learning procedure and global hybrid Monte Carlo/Markov Chain Monte Carlo optimization scheme. By suitable parameterization of geochemical and geophysical parameters, we simulated 1,500 training samples, out of which 50 % samples were used for training and remaining 50 % were used for validation and testing. We show that the trained model is able to classify validation and test samples with 85 % and 80 % accuracy respectively. Based on cross-correlation analysis and Gibb’s diagram of geochemical attributes, the groundwater qualities of the study area were classified into following three categories: “Very good”, “Good”, and “Unsuitable”. The BNN model-based results suggest that groundwater quality falls mostly in the range of “Good” to “Very good” except for some places near the Arabian Sea. The new modeling results powered by uncertainty and statistical analyses would provide useful constrain, which could be utilized in monitoring and assessment of the groundwater quality.  相似文献   

3.
针对目前水质综合评价中常规方法存在的问题 ,提出了径向基函数网络模型 (简记为 RBF-ANN)。以吉林省白城市地下潜水水质资料为例 ,运用该方法对监测样点进行了综合评价。通过与其它方法对比 ,结果表明 ,利用RBF-ANN模型进行水环境质量综合评价不仅方法简便 ,而且结论更接近客观实际。  相似文献   

4.
模糊-主成分分析综合评价法在地下水水质评价中的应用   总被引:1,自引:0,他引:1  
主成分分析法可以在保留数据原始信息的基础上有效地降低数据维度,从而将影响地下水质的多因子简化为几个综合因子,但对地下水的综合水质状况无法直接表达;模糊综合评价法能直接给出水体综合水质情况结论,但评价因子多为人为选取,存在较强的主观性。以辽宁思山岭矿区地下水水质现状评价为例,利用主成分分析法选取影响各断面水质的关键因子,将其作为模糊综合评价的评价因子,建立了模糊?主成分分析综合评价法的地下水水质耦合评价模型。研究结果表明,该模型能很好地体现分析因子对评价结果带来的影响,使得评价结果更科学、合理。  相似文献   

5.
Monitoring networks aiming to assess the state of groundwater quality and detect or predict changes could increase in efficiency when fitted to vulnerability and pollution risk assessment. The main purpose of this paper is to describe a methodology aiming at integrating aquifers vulnerability and actual levels of groundwater pollution in the monitoring network design. In this study carried out in a pilot area in central Italy, several factors such as hydrogeological setting, groundwater vulnerability, and natural and anthropogenic contamination levels were analyzed and used in designing a network tailored to the monitoring objectives, namely, surveying the evolution of groundwater quality relating to natural conditions as well as to polluting processes active in the area. Due to the absence of an aquifer vulnerability map for the whole area, a proxi evaluation of it was performed through a geographic information system (GIS) methodology, leading to the so called “susceptibility to groundwater quality degradation”. The latter was used as a basis for the network density assessment, while water points were ranked by several factors including discharge, actual contamination levels, maintenance conditions, and accessibility for periodical sampling in order to select the most appropriate to the network. Two different GIS procedures were implemented which combine vulnerability conditions and water points suitability, producing two slightly different networks of 50 monitoring points selected out of the 121 candidate wells and springs. The results are compared with a “manual” selection of the points. The applied GIS procedures resulted capable to select the requested number of water points from the initial set, evaluating the most confident ones and an appropriate density. Moreover, it is worth underlining that the second procedure (point distance analysis [PDA]) is technically faster and simpler to be performed than the first one (GRID?+?PDA).  相似文献   

6.
对国际标准化组织(ISO)在《水样采集与处理的质量控制指南》中提出的采样精密度控制方法不完全适用于地下水有机污染调查评价工作的部分进行了分析。在华北平原地下水有机污染调查评价工作的基础上,探讨了一种改进的采样精密度控制与评估方法,提高相关工作的质量控制水平。  相似文献   

7.
漯河市城市生态环境质量定量评价   总被引:2,自引:1,他引:1  
从自然生态环境质量、社会生态环境质量和经济生态环境质量3个方面构建了漯河市城市生态环境质量评价指标体系,采用层次分析法确定了各评价指标的权重值,借助综合评价模型计算了评价指标体系的综合指标值.并对城市生态环境质量现状进行了评价.结果显示,漯河市综合生态环境质量中等,其中,自然生态环境质量较好,社会生态环境质量中等,经济生态环境质量差.评价结果与定性评价结果相符,表明评价指标体系具有较强的科学性和实用性.依据评价结果,提出改善城市生态环境的对策和建议.  相似文献   

8.
Waste disposal facilities are mainly responsible for the gradual quality degradation of subsurface freshwater reservoirs. The main objective of this work is to identify the groundwater contamination risk due to potential leachate leakage and seepage beneath the municipal landfill of the City of Patras in Greece. A groundwater and leachate mass transport model of the underlying aquifer was developed for this purpose. The derived simulation results indicate that, depending on the permeability of the soil at the location of leakage, the contamination risk for the groundwater can be high. In order to quantify the magnitude and the extent of the leakage, a risk assessment model for the leachate contaminant plume was developed. The risk assessment analysis shows that the municipal drinking wells are under high risk of contamination.  相似文献   

9.
Sensitivity analysis is becoming increasingly widespread in many fields of engineering and sciences and has become a necessary step to verify the feasibility and reliability of a model or a method. The sensitivity of the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method in water quality assessment mainly includes sensitivity to the parameter weights and sensitivity to the index input data. In the present study, the sensitivity of TOPSIS to the parameter weights was discussed in detail. The present study assumed the original parameter weights to be equal to each other, and then each weight was changed separately to see how the assessment results would be affected. Fourteen schemes were designed to investigate the sensitivity to the variation of each weight. The variation ranges that keep the assessment results unchangeable were also derived theoretically. The results show that the final assessment results will change when the weights increase or decrease by ±20 to ±50 %. The feedback of different samples to the variation of a given weight is different, and the feedback of a given sample to the variation of different weights is also different. The final assessment results can keep relatively stable when a given weight is disturbed as long as the initial variation ratios meet one of the eight derived requirements.  相似文献   

10.
基于近些年的调查和监测结果,统计分析了我国地下水环境质量基本状况及主要超标指标的地区分布情况。指出,当前我国地下水环境监测工作主要由自然资源、水利、生态环境等部门分别组织开展,存在地下水监测信息共享与整合难度较大、尚未形成全国统一的地下水环境监测体系、“双源”地下水监测现状尚未摸清、地下水监测能力明显不足、地下水监测的生态环境保护作用尚未体现等问题。提出,进一步推动部门资源共享与整〖JP2〗合、统一全国地下水监测体系、优化完善考核机制、尽快摸清地下水监测现状和逐步提升监测能力等工作建议,以期为下一阶段全国地下水环境监测工作提供借鉴。  相似文献   

11.
A study on the orbit of air temperature movement   总被引:1,自引:0,他引:1  
In this paper, we describe an air temperature movement by mapping its time series to the polar coordinates: the value of the time series is plotted on the radial coordinate and the time on the angular coordinate. In this way, both the yearly and daily air temperature movements from five different locations of China are used to demonstrate that, in an intuitionistic view, air temperature movement is neither random nor chaotic, but has its own orbit. We then propose an elliptic orbit model for the air temperature movement. Our proposed model provides quite good results when it is applied to the evaluation of yearly air temperature movements in eight locations in various parts of the world, and the evaluation of daily air temperature movements in five locations in Hunan Province of China on December 17, 2005. Results show that our approach provides a concise and helpful model for air temperature analysis.  相似文献   

12.
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   

13.
Physical morphology is an important attribute of a stream system. The morphological state of a natural pristine stream often reflects its biological condition because of their close links. In contrast, the morphology of an urban stream may exhibit different behaviours due to serious human disturbances. For an urban stream system, the morphological condition not only determines the in-stream habitat quality but also provides the physical basis for the stream’s municipal functionalities. By comparing the morphological characters of urban and natural streams, this paper develops an integrated index system and model for the assessment of urban stream morphology. The model is applied to the Ancient Canal (Zhenjiang, China) with the aim of comparing the morphological conditions of reaches with and without ongoing restoration programs and further of assessing the effectiveness of the restoration methods and techniques. The results indicate that the water security and the landscape functionality of the canal have been upgraded. However, the quality of the in-stream habitat has been degraded as a result of the restoration. Based on the modelled results, recommendations are given for improving the effects of the next-phase restoration. The assessment system and findings from the application presented here are expected to have important implications for the restoration of disturbed urban streams in many other cities in China and elsewhere in the world.  相似文献   

14.
为科学开展监测井评估,选择井口保护装置/井口状况、井管内径、上部井管保存状态、是否串层、井结构保存状态、井的连通性6个指标,建立监测井维护评估和监测井功能评估方法,构建地下水环境监测井评估体系。监测井维护评估最终的评估结果分为无需修复、修复和报废,用于指导地下水环境监测井维护管理,使之满足长期监测要求;监测井功能评估最终的评估结果分为监测功能良好、监测功能一般和不具有监测功能,用于判定监测井的监测功能状况,是否可以执行当前监测任务。研究可为健全地下水环境监测网络,规范开展地下水环境监测提供技术支撑。  相似文献   

15.
我国典型村庄农村环境质量监测与评价   总被引:2,自引:1,他引:1  
选取典型村庄,基于农村环境质量监测和评价方法,对典型村庄2014年农村环境质量进行监测和评价,结果表明:典型村庄环境空气质量状况总体良好,达标比例为82.0%,超标村庄多分布在中国西北地区;农村饮用水源地水质较差,总体水质达标比例为67.1%,地表水和地下水饮用水源地水质达标比例分别为89.8%和52.6%;农村地表水环境质量欠佳,Ⅰ~Ⅲ类水质断面占72.7%,饮用水水源地和地表水水质各地区均存在超标村庄;部分地区土壤重金属超标问题较为突出,出现监测项目超标情况村庄占20.6%,土壤超标村庄主要集中在中国东北、华中和华南等地区;农村生态质量状况相对较好,"较差"和"差"的县域主要分布在中国西北和华中北部地区。  相似文献   

16.
Hydrochemical investigations of the groundwater and the seasonal effect on the chemical budget of ions along the course of the polluted river Adyar were carried out. From the geochemical results, it has been found that the seasonal effect does not change the order of abundance of both cations and anions, but it does change the concentration of various ions present in the groundwater. Among the chemical budget of ions, sodium and chloride were found to be the most predominant ions. The nitrate concentration in the groundwater ranges from 4.21 to 45.93 mg/l in pre-monsoon and in post-monsoon it ranges from 1.02 to 75.91 mg/l. The nitrate concentrations in the post-monsoon are high in some places especially in the upper stretch of the river. The intense agricultural activities near the upper stretch of the river may be an important factor for the higher concentration of nitrates in these aquifers. In order to determine the geochemical nature of water, the data was interpreted using the piper diagram wherein the results show the predominance of NaCl and CaMgCl types. Equiline diagrams, 1:1, were applied to evaluate the affinity ion relationship between various ions present in these waters. The quality of the groundwater was assessed with regard to its suitability to drinking and irrigation. A comparison of the groundwater quality in relation to drinking water quality standards shows that most of the water samples are not suitable for drinking, especially in post-monsoon period. US Salinity Laboratory's, Wilcox's diagrams, Kellys ratio and magnesium ratio were used for evaluating the water quality for irrigation which suggest that the majority of the groundwater samples are not good for irrigation in post-monsoon compared to that in pre-monsoon. Moreover the source of the ions in the water was examined and classified accordingly using Gibb's diagram. The analytical results reveals that the TDS values of the pre-monsoon samples were found to be lower than the post-monsoon reflecting that leaching predominates over that of the dilution factor.  相似文献   

17.
基于改进的多目标决策的水环境质量综合评价   总被引:1,自引:0,他引:1  
在对水环境质量综合评价中,多目标决策-理想区间法解决了水环境质量评价标准是区间而非点的缺陷。但是在计算监测点到各理想区间向量的距离时,各水环境质量指标权重直接影响综合评价的结果,通常的确定方法是简单的假设各水环境质量指标的权重相等,这与实际情况相悖。为了解决这一问题,提出了将超标法用于多目标决策法中,利用超标法确定各水环境质量指标的权重,然后将其应用于多目标决策-理想区间法来分析水环境质量等级。并将改进后的多目标决策-理想区间法应用于珠江口及邻近海域的水环境中。基于超标法确定权重的多目标决策-理想区间法与聚类分析相比更有效,与等权重的多目标决策-理想区间法相比,更能体现水环境的污染状况,可应用于各种环境因子的综合评价中。  相似文献   

18.
Eco-environment quality evaluation is an important research theme in environment management. In the present study, Fuzhou city in China was selected as a study area and a limited number of 222 sampling field sites were first investigated in situ with the help of a GPS device. Every sampling site was assessed by ecological experts and given an Eco-environment Background Value (EBV) based on a scoring and ranking system. The higher the EBV, the better the ecological environmental quality. Then, three types of eco-environmental attributes that are physically-based and easily-quantifiable at a grid level were extracted: (1) remote sensing derived attributes (vegetation index, wetness index, soil brightness index, surface land temperature index), (2) meteorological attributes (annual temperature and annual precipitation), and (3) terrain attribute (elevation). A Back Propagation (BP) Artificial Neural Network (ANN) model was proposed for the EBV validation and prediction. A three-layer BP ANN model was designed to automatically learn the internal relationship using a training set of known EBV and eco-environmental attributes, followed by the application of the model for predicting EBV values across the whole study area. It was found that the performance of the BP ANN model was satisfactory and capable of an overall prediction accuracy of 82.4%, with a Kappa coefficient of 0.801 in the validation. The evaluation results showed that the eco-environmental quality of Fuzhou city is considered as satisfactory. Through analyzing the spatial correlation between the eco-environmental quality and land uses, it was found that the best eco-environmental areas were related to forest lands, whereas the urban area had the relatively worst eco-environmental quality. Human activities are still considered as a major impact on the eco-environmental quality in this area.  相似文献   

19.
The exploration, exploitation, and unscientific management of groundwater resources in the National Capital Territory (NCT) of Delhi, India have posed a serious threat of reduction in quantity and deterioration of quality. The objective of the study is to determine the groundwater quality and to assess the risk of groundwater pollution at Najafgarh, NCT of Delhi. The groundwater quality parameters were analyzed from the existing wells of the Najafgarh and the thematic maps were generated using geostatistical concepts. Ordinary kriging and indicator kriging methods were used as geostatistical approach for preparation of thematic maps of the groundwater quality parameters such as bicarbonate, calcium, chloride, electrical conductivity (EC), magnesium, nitrate, sodium, and sulphate with concentrations equal or greater than their respective groundwater pollution cutoff value. Experimental semivariogram values were fitted well in spherical model for the water quality parameters, such as bicarbonate, chloride, EC, magnesium, sodium, and sulphate and in exponential model for calcium and nitrate. The thematic maps of all the groundwater quality parameters exhibited an increasing trend of pollution from the northern and western part of the study area towards the southern and eastern part. The concentration was highest at the southernmost part of the study area but it could not reflect correctly the groundwater pollution status. The indicator kriging method is useful to assess the risk of groundwater pollution by giving the conditional probability of concentrations of different chemical parameters exceeding their cutoff values. Thus, risk assessment of groundwater pollution is useful for proper management of groundwater resources and minimizing the pollution threat.  相似文献   

20.
The increasing demand of water has brought tremendous pressure on groundwater resources in the regions were groundwater is prime source of water. The objective of this study was to explore groundwater potential zones in Maheshwaram watershed of Andhra Pradesh, India with semi-arid climatic condition and hard rock granitic terrain. GIS-based modelling was used to integrate remote sensing and geophysical data to delineate groundwater potential zones. In the present study, Indian Remote Sensing RESOURCESAT-1, Linear Imaging Self-Scanner (LISS-4) digital data, ASTER digital elevation model and vertical electrical sounding data along with other data sets were analysed to generate various thematic maps, viz., geomorphology, land use/land cover, geology, lineament density, soil, drainage density, slope, aquifer resistivity and aquifer thickness. Based on this integrated approach, the groundwater availability in the watershed was classified into four categories, viz. very good, good, moderate and poor. The results reveal that the modelling assessment method proposed in this study is an effective tool for deciphering groundwater potential zones for proper planning and management of groundwater resources in diverse hydrogeological terrains.  相似文献   

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