潘集矿区塌陷水域水质评价及其综合利用

采煤塌陷水域是淮南潘集矿区一种特殊的地表水体.为了对潘集矿区塌陷水域进行水质评价和提供水资源综合利用的理论基础,选择了潘一矿区典型的两个塌陷水域,采用格网法布设39个采样点对水质进行全面采样监测,分析了水体的重金属元素和部分理化指标并运用数学模糊综合评判法对水质进行了评价.结果表明,封闭性较好的l'水域水质由水体中间向两岸呈递减趋势,中间断面水质为Ⅲ类;与泥河连通的2#水域水质较差,所有监测断面水质均为Ⅳ、Ⅴ类.由于矿业污染源的影响,导致2#水域的重金属元素污染强度高于1#水域.各塌陷水域均已受到不同程度污染,然而丰富的塌陷水资源若合理保护和综合开发利用可带来显著的环境效益和经济效益.     

基于反距离加权插值法评价海域水质类别空间分布

空间插值技术可以对污染物分布状况进行面状连续表征,是对点位法评价的有效补充。笔者根据现行海水水质评价方法,类比给出近岸海域水质类别空间分布评价的流程:单指标空间插值-单指标水质分类-多指标水质类别判定。研究了反距离加权插值参数的选取方法,并以点位密度不同的全国近岸海域(开放型)和渤海海域(近封闭型)为例进行了插值实验。 结果表明:对目前的点位分布情况而言,全国近岸海域参数设为p=3,N=4, C=200m较为适宜；渤海海域参数为p=2,N=5,C=200m较为适宜。反距离加权插值法在开放海域的拟合效果要优于近封闭海域。     

水污染指数法在河流水质评价中的应用研究

为满足我国水质评价与管理的需要,针对单因子评价法和综合污染指数法在水质评价中存在的问题,提出了水污染指数法。采用该方法对湘江干流2009年的水质状况进行了试评价,并将评价结果与单因子评价法、综合污染指数法、模糊综合评判法以及主成分分析法的评价结果进行了对比。结果表明,水污染指数法在水质类别评价、水质定量评价、主要污染指标识别、劣Ⅴ类水体水质比较等方面均具有明显优势,同时,该方法计算过程简单、易掌握,具有较强的推广、应用价值。     

用模糊线性加权变换法进行水质综合评价

用模糊数学方法对水质进行综合评价,已有报导.常用的方法是模糊综合评价法,当算子均匀分布在模糊关系矩阵R时,此法较准确.由于环境水质中大多数污染物浓度较低,且接近于第Ⅰ级水质标准,在对第Ⅰ级水质隶属度评估时,算子损失太多,从而影响到整个评价结果.本文应用的模糊线性加权变换法是基于模糊关系矩阵R,并综合模糊变换和线性     

北京市妫水河水质现状评价

2017年分3个时期(丰水期、平水期、枯水期)采集妫水河及其支流12个断面表层水样,分析了COD、氨氮、TP、DO、pH值等水质指标,采用单因子评价法、水污染指数法、主成分分析法和模糊综合评价法对水质进行评价,根据4种水质评价方法的评价结果,分析4种方法在小流域河流评价中的适用性。结果表明:目前妫水河12个断面中S2、S10和Z2 3个断面水质较差,基本属于地表Ⅴ类水,污染程度为重度污染;其他9个断面水质等级为地表Ⅳ类水,污染程度为中度污染;中段世园会段水质较好,优于上段和下段,主要污染指标为COD;妫水河主要污染源于农业和生活,枯水期水质优于平水期和丰水期。水污染指数法更适合小流域水体水质的定性定量评价,且计算方便简单。     

代表性水质评价方法的比较研究

从太湖流域国控断面常规监测数据出发,利用代表性水质评价方法对各断面进行评价,系统分析比较这些方法的优缺点。结果显示:①单因子指数法评价结果比较保守;②内梅罗指数法将"1"作为清洁与污染的分界点,指数偏小;③灰色关联分析法水质指标权重系数的确定较模糊综合评判法合理,结果也更接近于综合水质标志指数法;④综合水质标志指数法评价结果与其它评价方法结果重合度最高,且模糊评判法、灰色关联分析法和BP-ANN法的评价结果均向综合水质标志指数法逼近。综合水质标志指数法以单因子指数法为基础,对劣Ⅴ类水进行细化,将恶臭对水质的不利影响考虑其中,其指数组成合理,且易于操作施行。     

江苏推出太湖流域水环境综合治理总体方案

近日，江苏省政府推出《太湖流域水环境综合治理实施方案》，确定到2012年太湖湖体水质由2005年的劣Ⅴ类提高到Ⅴ类，其中高锰酸盐指数达到Ⅲ类，氨氮达到Ⅱ类，总磷达到Ⅳ类，总氮基本达到Ⅴ类；到2020年，基本实现太湖湖体水质从Ⅴ类提高到Ⅳ类的目标，其中部分水域达到Ⅲ类。富营养化程度有所改善，达到轻度-中度富营养水平。     

云龙湖水质调查与评价

对云龙湖水质进行了调查与评价.在云龙湖东湖、西湖区各设置3个采样点,监测水体中TN、TP、Imn、NH3-N、DO和SD指标;分别使用模糊识别法和湖泊综合营养指数对水体进行水质评价与富营养化评价,结果表明,云龙湖水质级别为III类,其中TN、TP超标明显,水体呈现中度富营养化;不同功能区水质差异明显,东湖区水质优于西湖...     

花溪区思雅河水质分析与评价

在花溪区思雅河大学城段布设10个采样点,监测pH值、温度(T)、悬浮物(SS)、化学需氧量(COD)、氨氮(NH_3-N)、总磷(TP)和细菌总数(TPC)等指标,并采用单因子指数法、综合指数法和模糊综合法3种方法对水质进行评价。结果表明:河流主要污染指标为COD,且增势最明显,TPC和NH_3-N测定值的RSD均超过1,比其他指标变异程度更大;COD和TPC春冬季测定值高于夏秋季,NH_3-N测定值秋季最低,TP季节变化不明显,而冬季测定值较其他季节更稳定;思雅河大学城段水质较差,上游水质等级为Ⅳ类,中下游为劣Ⅴ类,主要污染源自农业和高校生活用水;3种方法中,模糊综合法更适用于小流域河流水质的定性定量评价,评价结果更加科学合理。     

应用模糊综合指数法对伊犁河（伊宁段）水质的综合评价

模糊数学法对伊犁河(伊宁段)水质进行综合评价时,由于分别采用地面水环境质量标准中五类标准值的平均值及其中三个标准值,计算后的结果不一致,而模糊综合指数法避免了这类问题的出现,计算结果比较满意.从而表明,该法是对模糊数学法的进一步改进.     

Comparison of Point Estimation Techniques in the Spatial Analysis of Radium-226, Radium-228 and Potassium-40 in Soil

Many environmental surveys require the implementation of estimation techniques to determine the spatial distribution of the variable being investigated. Traditional methods of interpolation and estimation, for example, inverse distance squared and triangulation often ignore features of the data set such as anisotropy which may have a significant impact on the quality of the estimates produced. Geostatistical techniques may offer an improved method of estimation by modelling the spatial continuity of the variable using semi-variogram analysis. The theoretical model fitted to the semi-variogram is then used in the assignation of weighting factors to the samples surrounding the location to be estimated. This paper outlines the results of a comparison between three common estimation methods, polygonal, triangulation and inverse distance squared and a geostatistical method, in the estimation of soil radionuclide activities. The geostatistical estimation method known as kriging performed best over a range of parameters used to test the performance of the methods. Kriging exhibited the best correlation between actual and estimated values, the narrowest error distribution and the lowest overall estimation error. Polygonal estimation was best at reproducing the data set distribution. Conditional bias was evident in all the methods, low values being over-estimated and high values being under-estimated.     

山区土壤重金属空间插值性能的改进

山区土壤重金属监测中,密集均匀的布点采样困难大,成本高。根据稀疏非均匀样本数据准确预测山区土壤重金属空间分布,对可视化描述检测元素的分布及趋势具有重要意义。基于云南省楚雄市南部山区表层土壤中重金属锰、钒的采样数据,对集成径向基函数神经网络(IRBFANNs)和传统插值方法:反距离(IDW)、普通克里格(OK)、径向基函数神经网络(RBFANNs),进行了不同等级采样密度下的插值性能比较。结果表明,样本点数量减少时,传统预测方法的插值精度都有所下降,而IRBFANNs算法在样本点较少情况下能够保持最好的插值精确度和稳定性,有效改进了空间插值性能。     

基于GIS的新疆年降水量空间插值精度比较研究

以新疆具有完整资料的90个气象站点中的75个站点的基本地理信息和1995—2008年平均降水数据资料为基础,以ArcGIS为数据处理平台,分别采用反距离加权法、径向基函数法、普通克里格法、协克里格法对新疆降水空间分布进行插值,并通过没有参与插值的15个气象站点的实际降水量与插值结果进行相对误差分析。研究结果表明:在年降水量插值的4种算法中,普通克里格法(Kriging)的计算精度最高。利用最优的插值方法的栅格降水空间数据库建立的多年降水资源信息系统,可快速计算研究区内任一地域单元中降水的总量及其空间变化,对降水资源模拟、工程规划、发展战略及决策管理均具有重要的意义。     

Geostatistical Evaluation of Spatial Variation Related to Groundwater Quality Database: Case Study for Arak Plain Aquifer,Iran

Geostatistical methods are one of the advanced techniques to interpolate groundwater quality data. Geostatistical interpolation techniques employ both the mathematical and the statistical properties of the measured points. Compiling the data distribution on spatial and temporal domain is of crucial importance in order to evaluate its quality and safety. The main purpose of this paper is to assess groundwater quality of Arak plain, Iran, by an unbiased interpolated method so called Kriging. Therefore, seven quality variables of Arak plain aquifer including TDS, SAR, EC, Na⁺, TH, Cl^?, and SO₄ ^2? have been analyzed, studied, and interpreted statistically and geostatistically. Utilized data in this study were collected from 97 water well samples in Arak plain, in 2012. After normalizing data, variogram as a geostatistical tool for defining spatial regression was calculated and experimental variograms have been plotted by GS⁺ software, then the best theoretical model was fitted to each variogram based on minimum RSS error. Cross validation was used to determine the accuracy of the estimated data. The uncertainty of the method could be well assessed via this method since the method not only gave the average error (around 0 in this study) but also gave the standard deviation of the estimations. Therefore, more than 3800 points were estimated by ordinary Kriging algorithm in places which have not been sampled. Finally, estimation maps of groundwater quality were prepared and map of estimation variance, EV, has been presented to assess the quality of estimation in each estimated point. Results showed that the Kriging method is more accurate than the traditional interpolation algorithms not honoring the spatial properties of the database.     

GIS技术在东昌湖水质评价中的应用

利用GPS定位对东昌湖进行水样采集,把水质数据和坐标联系在一起,测定的结果利用GIS技术进行克里格插值.在用一部分数据验证其准确性之后,把全部水质数据以图的形式呈现出来,进行分析评价,通过与湖泊营养类型标准对比得出东昌湖大部分湖区出现富营养化现象,污染严重.证明GIS技术可以很好地应用于湖泊水质研究.     

Influence of water salinity on corrosion risk—the case of the southern Baltic Sea coast

Water corrosivity in Gdansk Bay, Poland, the southern part of the Baltic Sea, was investigated. The analysed region is heavily industrialized, and the coastline is very diverse. Twenty-seven test points along the coastline were selected. Water parameters such as salinity, total dissolved solids content, resistivity, conductivity, oxygenation, pH and corrosion rate were determined. The results of the investigation are presented. Water samples were collected, and structural steel specimens were exposed in the water for 2 months. The corrosion rate for each test point was determined and plotted on a map. The spatial distribution of water parameters was calculated using the ‘inverse distance to a power’ method and presented on the maps. Salinity did not exceed 0.7 %, and average corrosion rate equalled 0.0585 mm/year.     

Temporal and spatial variability in water quality of wetlands in the Minneapolis/St. Paul,MN metropolitan area: Implications for monitoring strategies and designs

Temporal and spatial variability in wetland water-quality variables were examined for twenty-one wetlands in the Minneapolis/St. Paul metropolitan area and eighteen wetlands in adjacent Wright County. Wetland water quality was significantly affected by contact with the sediment (surface water vs. groundwater), season, degree of hydrologic isolation, wetland class, and predominant land-use in the surrounding watershed (p<0.05). Between years, only nitrate and particulate nitrogen concentrations varied significantly in Wright County wetland surface waters. For eight water-quality variables, the power of a paired before-and-after comparison design was greater than the power of a completely randomized design. The reverse was true for four other water-quality variables. The power of statistical tests for different classes of water-quality variables could be ranked according to the predominant factors influencing these: climate factors>edaphic factors>detritivory>land-use factors>biotic-redox or other multiple factors.For two wetlands sampled intensively, soluble reactive phosphate and total dissolved phosphorus were the most spatially variable (c.v.=76–249%), while temperature, color, dissolved organic carbon, and DO were least variable (c.v.=6–43%). Geostatistical analyses demonstrated that the average distance across which water-quality variables were spatially correlated (variogram range) was 61–112% of the mean radius of each wetland. Within the shallower of the two wetlands, nitrogen speciation was explained as a function of dissolved oxygen, while deeper marsh water-quality variables were explained as a function of water depth or distance from the wetland edge. Compositing water-quality samples produced unbiased estimates of individual sample means for all water quality variables examined except for ammonium.     

Design of River Water Quality Monitoring Networks: A Case Study

Karoon River, from Gotvand Dam to Persian Gulf with more than 450 km in length and an annual discharge of 11,891 million cubic meters, is the largest river in Iran. Increasing water withdrawal from and wastewater discharge to the river has endangered the aquatic life of this important ecosystem. Furthermore, the drinking and in-stream water quality standards have been violated in many instances. In this paper, a river water quality monitoring network is designed, including determination of sampling frequencies as well as location of water quality monitoring stations. In this regard, two models are developed. The first model is a Genetic Algorithm-based optimization model and the second one is a combination of Kriging method and Analytical Hierarchy Process. The temporal variation of the concentration of water quality variables along Karoon and Dez Rivers are evaluated and the main water quality indicators are selected. Then, thirty five stations are selected and the application of Entropy Theory in calculating the sampling frequency is demonstrated. The results show the significant value of the proposed methodology in the design of monitoring network.     

Kriging and Bilinear Methods for Estimating Spatial Pattern of Atmospheric Pollutants

Two statistical methods to reconstruct the spatial pattern ofenvironmental data are compared: the Kriging and the Bilinear.The comparison is performed by evaluating two differentcharacteristics of the methods: the interpolation and the estimation. The Kriging method is demonstrated to be better thanthe Bilinear regarding all the statistics studied, although thedifferences are not very significant. Especially, the Kriging ismore efficient than the Bilinear in the reconstruction of peakvalues and it does not extrapolate local trends. The methods areapplied to a set of environmental data measured in an urban area.     

基于反距权重插值的入海河口水环境研究

对某入海河口在春季和夏季进行2次水体环境因子(TP、TN、COD、Chla、SS)监测,利用Arc Map扩展模块中反距离权重插值模型,对各监测值分别进行插值分析。通过插值结果,对营养盐、Chla、COD和SS在时间和空间上的差异进行探讨,揭示了入海河口水体环境因子在季节差异和流域分布上的独有特点。