Testing the MAGIC acid rain model in highly organic,low-conductivity waters using multiple calibrations

Accurate predictions of acid precipitation effects on water resources are important in order to allow a better understanding of various pollution control strategy outcomes. Dynamic geochemical models have been developed to address this need, but have to be tested under a variety of environmental conditions to provide confidence in their predictions. The most commonly used aquatic acidification model in North America and Europe is the model of acidification of groundwater in catchments (MAGIC). Though extensively used, MAGIC has never been tested in catchments with extremely low ionic strength water and high in natural organic acids (NOAs) from wetlands, two conditions which are common in large parts of Canada. We calibrated the model for two catchments located in Nova Scotia, Canada, which had some of the most dilute freshwaters reported in the literature and very high NOA. We also evaluated the variability inherent in calibration data sets by using five separate data sets collected over a 15-year period at the same sites. We show good model simulations for the main cations and anions in catchment waters. However, modeling pH is more difficult in the highly organic waters and requires modification to the acid dissociation constants. Calculated acid neutralization capacity can also be more difficult to model due to the low ion content making small errors more important. In theory, multiple calibrations of a model at a same site should produce identical hindcasts and predictions. In reality, the multiple calibrations produced a series of similar, but not identical outcomes which give a probable range of past values and future outcomes. We feel that this practical approach to validation is a useful addition to the arsenal of model testing tools.     

南通长江口北支咸潮上溯对水环境的影响

针对长江口北支近20多年来咸潮超常上溯的状况,通过现场调查监测及与文献资料对比,分析了咸潮上溯对水源地供水水质、河口区河道水质和地下水水质的影响。结果表明,长江口北支咸潮上溯对北支水环境影响主要在于入侵时水体中电导率和氯化物浓度急剧升高,一定程度上影响了北支沿线水源地的供水功能。咸潮对现有水质评价体系下的水质类别影响尚不明显,但高氯离子对化学需氧量的测定有明显的干扰。由于受堤围和水闸控制,咸潮期间入江闸门普遍关闭,导致间接水环境影响,主要集中在入海主河道。部分区域咸潮上溯严重时氯化物浓度升高,水质已不能满足农田灌溉需求。北支沿线启东市24%的地下水采样点氯化物浓度已属轻度入侵水,采样区域已属于海水轻度入侵范围。     

A Methodology for Space-Time Classification of Groundwater Quality

Safeguarding groundwater from civil, agricultural and industrial contamination is matter of great interest in water resource management. During recent years, much legislation has been produced stating the importance of groundwater as a source for drinking water supplies, underlining its vulnerability and defining the required quality standards. Thus, schematic tools, able to characterise the quality and quantity of groundwater systems, are of very great interest in any territorial planning and/or water resource management activity.This paper proposes a groundwater quality classification method which has been applied to a real aquifer, starting from several studies published by the Italian National Hydrogeologic Catastrophe Defence Group (GNDCI).The methodology is based on the concentration values of several parameters used as indexes of the natural hydro-chemical water condition and of potential man-induced modifications of groundwater quality. The resulting maps, although representative of the quality, do not include any information on its evolution in time. In this paper, this “stationary” classification method has been improved by crossing the quality classes with three indexes of temporal behaviour during recent years. It was then applied to data from monitoring campaigns, performed in spring and autumn, from 1990 to 1996, in the plain of Modena aquifer (central Italy). The results are reported in the form of space-time classification table and maps.     

水质参数的遥感反演和遥感监测

遥感技术由于具有快速、宏观、低成本和周期性的优点,便于探测水质的时空变化,已成为水质参数监测的重要手段。目前能够直接进行遥感反演的水质参数主要是悬浮物浓度、叶绿素a浓度、可溶解性有机物等光学活性物质,并已经建立了许多反演模型。但是这些模型直接用于水质的遥感监测仍存在一些问题。今后,利用3S技术将地面观测和遥感观测结合起来,可望推动水色遥感的实际应用。     

乌鲁木齐市饮用水状况卫生监测分析

为了评价乌鲁木齐市居民饮用水卫生状况,对该市６个自来水厂的出厂水,末梢水和二次供水的水质及卫生设施进行监督监测。结果表明,该市居民供水水质基本符合国家生活饮水卫生标准规定,但末梢水和二次供水中余氯合格率偏低,分别为６１．０２％和４５％。二次供水设施使用的防水材料均未按国家规定输涉及水产品卫生许可批件。     

Qualidex – A New Software for Generating Water Quality Indice

Water quality indice are necessary for resolving lengthy, multi-parameter, water analysis reports into single digit scores. This, in turn, is essential for comparing the water quality of different sources and in monitoring the changes in the water quality of a given source as a function of time and other influencing factors.In this paper we present the computer-automated tool QUALIDEX (water QUALIty inDEX), which has been developed by us to generate and operate water quality indice. Several popular indice – such as the Oregon Water Quality Index developed in the 1970s by Oregon Department of Environmental Quality and later updated in 1995, the Aquatic Toxicity Index developed by Wepener and coworkers for protection of aquatic life at the Olifants river, Kruger National Park, South Africa, the water quality index developed by Dinius in 1987, the Overall Index of Pollution (of surface waters) developed at the National Environmental Engineering Research Institute (NEERI), and the water quality index of the Central Pollution Control Board (CPCB) – have also been added to QUALIDEX in modular form. There is also a New water quality index sub-module which enables the user to generate his or her own index and compare its performance with these well-known indice. The package is also capable of analyzing the variations in the water quality of different sites at different times. The software has been coded in Visual C++ and has been integrated with MS Access database.     

地表水环境质量定性评价

针对目前缺乏统一的地表水环境质量定性评价准则的现状,根据我国主要水体的污染程度,提出了断面、河流、水系水质定性评价方法。     

红枫湖水质变化趋势及环境保护政策综合分析

红枫湖是贵阳市重要的饮用水源地,由于城市化发展及诸多原因,自20世纪90年代以来水质受到一定程度污染.1995年省委、省政府立法保护红枫湖,并成立"两湖"领导小组,对红枫湖流域进行综合整治,使其水质得到不断改善.至2019年,红枫湖水体环境质量已经达到治理预期目标,各个监测点位水质从局部劣Ⅴ类改善至整体Ⅱ类.笔者回顾了...     

The use of multivariate statistical methods for optimization of the surface water quality network monitoring in the Paraopeba river basin,Brazil

This study sought to evaluate and propose adjustments to the water quality monitoring network of surface freshwaters in the Paraopeba river basin (Minas Gerais, Brazil), using multivariate statistical methods. A total of 13,560 valid data were analyzed for 19 water quality parameters at 30 monitoring sites, over a period of 5 years (2008–2013). The cluster analysis grouped the monitoring sites in eight groups based on similarities of water quality characteristics. This analysis made it possible to detect the most relevant monitoring stations in the river basin. The principal components analysis associated with non-parametric tests and the analysis of violation of the standards prescribed by law, allowed for identifying the most relevant parameters which must be maintained in the network (thermotolerant coliforms, total manganese, and total phosphorus). The discharge of domestic sewage and industrial wastewater, that from mining activities and diffuse pollution from agriculture and pasture areas are the main sources of pollution responsible for the surface water quality deterioration in this basin. The BP073 monitoring site presents the most degraded water quality in the Paropeba river basin. The monitoring sites BP094 and BP092 are located geographically close and they measure similar water quality, so a possible assessment of the need to maintain only one of the two in the monitoring network is suggested. Therefore, multivariate analyses were efficient to assess the adequacy of the water quality monitoring network of the Paraopeba river basin, and it can be used in other watersheds.     

河流水质月报评价项目的选择

以三种评价项目选择法对国控河流断面水质评价的结果进行了比较。结合现阶段我国的经济技术条件选择了适用于河流水质月报的评价项目即pH、溶解氧、高锰酸盐指数、五日生化需氧量、氨氮、石油类、挥发酚、汞和铅等9项。     

湘江衡阳段软体动物多样性调查和水质生物学评价

对衡山大源渡电站蓄水多年后的湘江衡阳段软体动物的种类组成、区系分布以及多样性进行了调查,并用生物多样性指数对湘江衡阳段水质进行了评价。调查结果表明,湘江衡阳段计有软体动物45种,分别隶属于2纲9科18属,其中腹足纲6科11属30种,双壳纲3科7属15种,其区系成分主要为东洋界类型;其中26种为中国特有种,且湖南湄公螺为濒危物种(被《中国物种红色名录》定为灭绝的物种)。用软体动物的Shannon-Wiener多样性指数(H’)对湘江衡阳段进行水质生物学评价,研究结果表明,湘江衡阳段的水质除东洲岛和衡山县城为清洁水外,其余8个采样点的水质均受到了轻度污染。     

Water Quality Evaluation and Trend Analysis in Selected Watersheds of the Atlantic Region of Canada

Water quality indices (WQIs) have been developed to assess the suitability of water for a variety of uses. These indices reflect the status of water quality in lakes, streams, rivers, and reservoirs. The concept of WQIs is based on a comparison of the concentration of contaminants with the respective environmental standards. The number, frequency, and magnitude by which the environmental standards for specific variables are not met in a given time period are reflected in WQIs. Further, the water quality trend analysis predicts the behavior of the water quality parameters and overall water quality in the time domain. In this paper, the concept of WQI was applied to three selected watersheds of Atlantic region: the Mersey River, the Point Wolfe River, and the Dunk River sites. To have robust study, two different water quality indices are used: Canadian Water Quality Index (CWQI), and British Columbia Water Quality Index (BWQI). The complete study was conducted in two steps. The first step was to organize and process the data into a format compatible with WQI analysis. After processing the input data, the WQI was calculated. The second step outlined in the paper discusses detailed trend analysis using linear and quadratic models for all the three sites. As per the 25 years trend analysis, overall water quality for agriculture use observed an improving trend at all the three sites studied. Water quality for raw water used for drinking (prior to treatment) and aquatic uses has shown improving trend at Point Wolfe River. It is further observed that pH, SO₄, and NO₃ concentrations are improving at Dunk River, Mersey River, and Point Wolfe River sites. To ascertain the reliability and significance of the trend analysis, a detailed error analysis and parametric significance tests were also conducted It was observed that for most of the sites and water uses quadratic trend models were a better fit than the linear models.     

WATER AND WASTEWATER QUALITY MONITORING, MCMURDO STATION, ANTARCTICA

McMurdo Station is the largest research station in Antarctica and has a population that ranges from 250 to 1200 people. Wastewater from the Station is macerated, was sometimes mixed with waste brine from the desalinization plant and is discharged to McMurdo Sound. Effluent water quality has been routinely monitored since 1989, and a special ambient water quality study was conducted by Idaho National Engineering Laboratory (INEL) personnel in 1992. Results of the effluent monitoring efforts show that low concentrations of a few organic contaminants have been detected, while concentrations of metals, particularly copper, are considerably higher. Ambient water quality and sea ice monitoring detected very few contaminants, all at very low levels. Only minor and variable dissolved oxygen depression was detected near the outfall. Diatom communities near the outfall differ in relative abundance, cell counts, and chlorophyll a content compared to control sites. For the purpose of evaluating the impact of McMurdo`s effluent on ambient water quality, improved effluent monitoring and sediment quality monitoring are recommended instead of frequent monitoring of ambient water quality.     

用射流曝气法处理医院污水的效果研究

研究了用射流曝气法处理医院污水的实际效果。从污水处理前后的水质变化、对比,证明了该方法在医院污水处理中所具有的优越性。     

黄河口的水质、底质污染及其变化

分析了2001年在黄河口附近所取的3处水样和3处泥样中污染物的含量,并与历史数据进行了比较.利用<地表水环境质量标准>(GB3838-2002)和美国国家海洋大气管理局(NOAA)水体泥沙质量标准等分别对水体和底泥中的重金属(砷)和氮磷污染进行了评价.认为黄河口的水污染严重,主要污染物为汞和氮;泥沙污染尚不严重,但污染物的增长率高;水体中较高的氮含量和泥沙中氮含量的迅速增高可能会对渤海湾的富营养化情况产生影响.     

Scatterscore: A Reconnaissance Method To Evaluate Changes In Water Quality

Water quality data collected in periodic monitoring programs are often difficult to evaluate, especially if the number of parameters is large, the sampling schedule varies, and values are of different orders of magnitude. The Scatterscore Water Quality Evaluation was developed to yield a quantitative score, based on all measured variables in periodic water quality reports, indicating positive, negative or random change. This new methodology calculates a reconnaissance score based on the differences between up-gradient (control) versus down-gradient (treatment) water quality data sets. All parameters measured over a period of time at two or more sampling points are compared. The relationship between the ranges of measured values and the ratio of the medians for each parameter produces a data point that falls into one of four sections on a scattergram. The number and average values of positive, negative and random change points is used to calculate a Scatterscore that indicates the magnitude and direction of overall change in water quality. The Scatterscore Water Quality Evaluation, a reconnaissance method to track general changes, has been applied to 20 sites at which coal utilization by-products (CUB) were used to control acid mine drainage (AMD).     

水质标准中指示微生物的发展及现状

饮用水病原微生物污染是公共卫生面临的主要威胁之一,微生物监测在水质监测中的必要性日益受到人们的认可。在实际工作中,一般是通过检测指示微生物间接反映病原微生物的存在。通过调研国内外各组织、机构颁布的水质标准发现,近年来,我国环境质量标准和污染物排放标准中对于指示微生物的选择有从总大肠菌群向粪大肠菌群和大肠埃希氏菌(E.coli)转变的趋势,而美国环保署、欧盟、世界卫生组织、澳大利亚国家健康与医疗研究委员会等根据最新的流行病学证据,强调了大肠埃希氏菌(E.coli)、肠球菌(Enterococci)与粪便污染的相关性更强,可用于替代大肠菌群。建议我国在后续水质标准中对微生物指标进行增补修订时,参考国外经验,形成集成多种指示微生物与多种特定病原体的监测指标体系,以更好地保护环境功能和民众健康。     

太湖主要入湖河流排污控制量研究

利用2006—2008年的监测数据对太湖主要入湖河流的水环境状况进行了分析,通过对研究区工业污染源、农业污染源和城镇生活污水排污的分布以及入河情况的调查,对各种污染源的入河量进行了计算,根据确定的水质目标,分别计算出主要入湖河流以及区域水系的水环境容量和排污控制量。结果表明:15条主要入湖河流超标现象显著,近3a来污染程度有所波动,N、P污染最为严重。研究区内污染物入河量较大,未接管的生活源污染物入河量所占比重最大,各类污染物均在50%～60%之间;张家港市的污染物入河量最大,各类污染物所占比重达总入河量的18%～20%。研究区内河网密布,水环境容量分布不均匀,望虞河、直湖港、武进港等7条河流水环境容量较大,张家港市区域水环境容量较大。为保证水质达标,研究区内近期共须削减CODCr66554.38t/a、NH4-N8105.71t/a、TP1324.42t/a;远期共须削减CODCr96719.08t/a、NH4-N11541.45t/a、TP1788.71t/a。     

基于遥感影像的木兰溪水质参数反演

水质监测对水环境评价及污染预防至关重要,但地面监测成本高、监测面积有限等,难以满足实时、大范围监测的要求。为了更好地解决该问题,基于遥感影像的空中监测技术越来越得到研究人员的青睐。以木兰溪为研究区,利用和地面监测数据同步的Landsat-8卫星遥感影像数据,对木兰溪的典型水质参数总磷、总氮、溶解氧、高锰酸盐指数的反演问题进行研究。首先,根据Landsat-8的水体敏感波段,分别选取总磷、总氮、溶解氧、高锰酸盐指数的反演特征波段组合为(b1-b2)/(b2+b3),(b1-b2)/(b3-b4),b2/(b1+b4),b1/b2;其次,利用反演特征波段组合分别构建总磷、总氮、溶解氧、高锰酸盐指数浓度的SVR(Support Vector Regression)反演模型,通过IPSO算法对SVR模型的参数进行优选;然后,将IPSO-SVR反演模型和统计回归反演模型、广义回归神经网络(GRNN)反演模型在验证集上进行评估,以平均绝对误差和均方根误差作为评价指标进行对比分析,结果表明IPSO-SVR反演模型的平均绝对误差和均方根误差最小,说明IPSO-SVR反演模型具有较高的精度和较好的实用性...     

Development of a Quality-Assessed Agrichemical Database For Monitoring Anthropogenic Impacts on Ground-Water Quality

The Quality–Assessed Agrichemical Contaminant Database for Nebraska Ground Water is a unique repository of nitrate and pesticide data collected by federal, state, and local agencies. Each contaminant concentration in the database has been evaluated based upon well–defined criteria that address completeness of the well–attribute data, analytical method and field and laboratory quality control practices and assigned to one of five quality levels. The quality assessment level always accompanies the contaminant concentration so that the end–user knows the quality assurance effort expended in the acquisition of the data, can select comparable data, and choose data whose quality assurance effort is commensurate with project objectives. The database can be viewed and queried on–line; downloaded in its entirety; or imported to a spreadsheet or a geographic information system. Setting criteria for data quality and assessing the level of quality have resulted in significant increases in the percentages of high quality (Levels 3–5) nitrate and pesticide data. These high quality data presently constitute 52% of the nitrate and 55% of the pesticide data.