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杭州市主城区浅层地下水水质现状 总被引:2,自引:1,他引:2
调查了杭州市主城区浅层地下水水质现状。结果表明,杭州市主城区浅层地下水污染较重,三氮超标现象普遍,而主要污染项目为NH3-N、NO2--N、IMn和总大肠菌群及细菌总数。指出,农业面源污染和生活污水,是造成杭州市主城区浅层地下水氮污染的主要原因。提出分析了地下水水质污染的成因。指出应加强地下水保护以及地下水资源的质量管理。进行科学、合理地开发利用,实现地下水水资源的可持续利用,支持杭州市国民经济的可持续发展。 相似文献
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BP人工神经网络模型在西鞍山铁矿地下水水质评价中的应用 总被引:2,自引:0,他引:2
以西鞍山铁矿为例,采用BP人工神经网络模型对区内12个监测点的水质进行评价。以枯水期水质监测的主成分总硬度、溶解性总固体、硫酸盐、氯化物、铁和锰、硝酸盐、氟化物指标作为评价因子,建立地下水评价指标体系,并将评价结果与模糊综合评价法及综合质量评价法的评价结果比较。结果表明,8、9、10、11号监测点属于Ⅰ类水,1、2、3、4、6、7、12号监测点属于Ⅱ类水,5号监测点属于Ⅲ类水,西鞍山铁矿的开采未对地下水造成影响;该方法与模糊综合评价法及综合质量评价法的评价结果基本一致,可以客观、合理性地评价水质。 相似文献
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基于2001—2011年洪泽湖水质溶解氧、高锰酸盐指数、总氮、氨氮和总磷长期定位监测数据,采用物元分析法研究洪泽湖渔业水质监测站位的优化布设。结果表明,用物元分析法将原来的21个监测站位优化为14个,监测点位优化后对监测结果无明显影响。 相似文献
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简述了长江南京段监测断面现状,用相关分析与聚类分析方法对水质监测数据进行了统计分析,对长江南京段水质自动监测优化布点提出了相关建议。 相似文献
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运用灰色理论建立水质预测模型,通过对水质指标拟合值与实测值差异性分析,判断模型精密度,并预测山东省东阿县下马头水源地未来2年的水质变化趋势,结果表明:在4项水质指标预测模型中,总硬度、氟化物指标的GM(1,1)时间响应预测模型拟合结果较好;溶解性总固体、硝酸盐指标的GM(1,1)时间响应预测模型精密度均为3级,不适合指标的预测;未来2年下马头水源地岩溶地下水水质良好。 相似文献
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河口海湾位于陆海交错带,受径潮流作用的双重影响,具有物质输运格局复杂、生态环境变化梯度大等特点。生态环境监测点位布设与优化是科学、客观评估河口海湾生态环境状况的前提。采用空间平衡抽样法开展监测点位增设和优化方案研究,将2020年5月上海市海洋环境趋势性监测布设的142个监测点位,增设至200个,并进一步优化至170个,对优化前后的点位数据进行显著性检验、方差分析和空间自相关分析。结果显示:2组数据之间无显著性差异,并且优化后点位的方差和空间自相关值更小,说明空间平衡抽样法适用于河口海湾生态环境监测点位布设和优化,点位布设和优化结果可客观反映河口海湾的生态环境状况。随后,采用泰森多边形法确定了优化所得的170个离散点位的海域代表面积,克服现有空间插值法的缺陷,为河口海湾生态环境总体状况评价提供技术参考。 相似文献
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序贯数论优化法和侧影图进行河流优化布点 总被引:3,自引:0,他引:3
运用序贯数论优化法(SNTO)对监测点进行分类,同时根据分类结果,基于样本之间的相似性和差异性,构造一Rousseuw定义的函数并做侧影图,以确定各属类的最佳代表点,从而遴选出优化了的点位. 相似文献
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胡晋 《环境监测管理与技术》2005,17(3):18-21
阐述了在Excel平台上建立的BP网络模型水质评价系统的方法和要点,以及网络模型结构的设计、训练数据的处理、网络的训练和评价结果的仿真情况。实例表明Excel建立的BP网络模型水质评价系统的评价结果客观,模型使用方便,有推广价值。 相似文献
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The long-term water quality monitoring program implemented by the Massachusetts Water Resources Authority in 1992 is extensive
and has provide substantial understanding of the seasonality of the waters in both Boston Harbor and Massachusetts Bay and
the response to improvements in effluent quality and offshore transfer of the effluent in September 2000. The monitoring program
was designed with limited knowledge of spatial and temporal variability and long-term trends within the system. This led to
an extensive spatial and temporal sampling program. The data through 2003 showed high correlation within physical parameters
measured (e.g., salinity, dissolved oxygen) and in biological measures such as chlorophyll fluorescence. To address the potential
sampling redundancies in the measurement program, an assessment of the impact of reduced levels of monitoring on the ability
to make water quality decisions was completed. The optimization was conducted by applying statistical models that took into
account whether there was evidence of a seasonal pattern in the data. The optimization used model survey average readings
to identify temporal fixed effects, model survey-average-corrected individual station readings to identify spatial fixed effects,
corrected the individual station readings for temporal and spatial fixed effects and derived a correlation model for the corrected
data, and applied the correlation model to characterize the correlation of annual average readings from reduced monitoring
programs with true parameter levels. Reductions in the number of sampling stations were found less detrimental to the quality
of the data for annual decision-making than reductions in the number of surveys per year, although there is less of a difference
in this regard for dissolved oxygen than there is for chlorophyll. The analysis led to recommendations for a substantially
lower monitoring effort with minimal loss of information. The recommendation supported an annual budget savings of approximately
$183,000. Most of the savings was from fewer surveys as approximately $21,000 came from the reduction in the number of stations
monitored from 21 to 7 and associated laboratory analytical costs. 相似文献
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Passarella G Vurro M D'Agostino V Giuliano G Barcelona MJ 《Environmental monitoring and assessment》2002,79(1):57-74
An approach to assess the risk of groundwater quality degradation with regard to fixed standards, based on DisjunctiveKriging (DK) is presented. The DK allows one to evaluate the Conditional Probability (CP) of overriding a given threshold of concentration of a pollutant at a given time, and at a generic point in a consideredgroundwater system. The result of such investigation over the considered area can be plotted in form of maps of spatial risk. By repeating this analysis at different times, severalspatial riskmaps will be produced, one for each consideredtime. By means of non-parametric statistics, the temporal trendof the CPs can be evaluated at every point of the considered area. The trend index, assessed by means of a sort of classification of the trend values obtained as described above,can be superimposed on the most recent values of the spatialrisk (i.e.: the most recent values of probability). Consequentlya classification of the risk of groundwater quality degradationresults with which to weigh both the spatial distribution and thetemporal behaviour of the probability to exceed a given standardthreshold. The methodology has been applied to values of nitrateconcentration sampled in the monitoring well network of theModena plain, northern Italy. This area is characterised by intensive agricultural exploitation and hog breeding along withindustrial and civil developments. The influence of agriculture on groundwater results in a high nitrate pollution that limitsits use for potable purposes. 相似文献
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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
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A statistical quality control approachto detect changes in groundwater quality from aregulated waste unit is described. The approachapplies the combined Shewhart-CUSUM control chartmethodology for intrawell comparison of analyteconcentrations over time and does not require anupgradient well. A case study from the U.S.Department of Energy's Hanford Site is used forillustration purposes. This method is broadlyapplicable in groundwater monitoring programs wherethere is no clearly defined upgradient location, thegroundwater flow rate is exceptionally slow, or wherea high degree of spatial variability exists inparameter concentrations. This study also indicatesthat the use of the Data Quality Objectives (DQO)process can assist in designing an efficient andcost-effective groundwater monitoring plan to achievethe optimum goal of both low false positive and lowfalse negative rates (high power). 相似文献
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水质监测是任何水资源管理必不可少的组成部分,水质监测与评价不仅可对水污染问题进行鉴别和评估,而且可以验证污染控制措施是否正确以及污染源是否遵守了相关的环保法规、制度。文章讨论了综合监测系统的对策、网络设计、采样与分析、数据处理与报告,还讨论了必需的科学的组织形式。以4条跨界河流[欧洲的莱茵河(Rhine)和多瑙河(Danube)、南美的拉普拉塔河(La Plata)、东南亚的湄公河(Mekong)]为例阐述了现代意义的监测方法学。对于工业化程度高的流域(如莱茵河和多瑙河),早期预警系统尤为重要。最后探讨了新的性价比好的污染监测方法以及如何避免产生数据很多,但信息量很少的状况。 相似文献
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Icaga Y 《Environmental monitoring and assessment》2005,108(1-3):261-277
Selection procedure of the optimum station combination for decreasing the station number from 33 to 14 in water quality monitoring network of Gediz river basin was applied using an optimization method. Gediz basin is one of the important basins and it covers 2.3% of the total surface area of Turkey. The technique includes two stages as the data preparation and the optimization. In the data preparation stage, firstly, alternative station combinations decreased and then station combination scores obtained from assigned selection criteria for point and nonpoint pollution management objectives. Finally, genetic algorithm applied to select the best combination. The results were compared with a prior solution that used dynamic programming as the optimization technique. 相似文献