滨州市浅层地下水化学时空变化及成因分析

随着海平面升高和全球气候变化,沿海城市地下水化学的长期演变规律研究变得尤为重要。通过采集2010～2020年滨州市浅层地下水样(250个),运用数理统计、ArcGIS空间插值、相关性分析、Piper三线图、Gibbs图及离子比等方法系统地分析了近10年来地下水化学时空演变规律及成因,结果表明:(1)研究区水体整体呈弱碱性,以微咸水为主,地下水阳离子以Na⁺为主,阴离子以Cl^-为主;由陆向海,水化学类型由Ca-SO₄·HCO₃型过渡到Na·Mg-HCO₃·SO₄、Na·Mg-Cl·HCO₃型,近海迅速转化为Na·Mg-Cl及Na-Cl型;(2)水化学组分年际变化表现为:TDS、Na⁺、Cl^-、SO₄^2-和NO₃^-在2012～2013年显著升高,2013～2020年波动降低,2013年区域TDS突增主要受海水入侵影响;水化学组分空间分布为:TDS、Na⁺、K⁺、Mg²⁺、Ca²⁺、Cl^-和SO₄^2-浓度空间变异不大,由陆向海浓度增高,并在博兴县北部沿黄河区域出现极大值,主要受河道补给状况影响;NO₃^-浓度空间变异较大,10年间在小清河流域浓度显著增高,增幅为15.81mg/(L·a);(3)由陆向海,水化学控制因素由岩石风化控制型过渡至蒸发浓缩控制型;(4)Ⅰ区Na⁺、Cl^-主要来源于岩盐及钠长石,Ⅱ区Na⁺来源受到上游生活污水影响,Ⅲ、Ⅳ区部分水体受海水影响较重,Na⁺、Cl^-可能来源于海水,SO₄^2-、Ca²⁺则主要来源于石膏。     

典型化工废渣污染土壤中汞的空间分布规律研究

为阐明氯碱厂废渣堆积遗留场地中汞的空间分布规律,在某典型场地设置313个表层（0.5 m）、79个深层（0.5～13.5 m）土壤采样点位及6个地下水采样点位,分析所有土壤样品的总汞浓度、表层土壤的理化性质及地下水总汞浓度.结果显示：（1）该场地土壤汞污染严重,313个表层土壤样点汞检出浓度为0.002～579.14 mg·kg^-1,平均为8.43 mg·kg^-1,高于《土壤环境质量农用地土壤污染风险管控标准（试行）》中的风险管控值(6 mg·kg^-1).反距离权重法（IDW）及自然邻域法（NNI）对该场地的汞水平浓度分布的插值更为准确.（2）79个深层点位土壤垂向检测结果显示,土壤上层区域（0.5、1.5、2.5 m）汞污染浓度更高,3个深度层的汞浓度平均值分别为7.3、5.5、3.1 mg·kg^-1,2.5 m以下7个深度层的汞浓度平均值仅为（1.02±0.15）mg·kg^-1;汞垂向富集因子为0.4～32,大多数（66%）采样点位汞的富集因子（EF）随着土壤深度增加显著下...     

Time-series sampling of Ra and Ra at the inlet to Great South Bay (New York): a strategy for characterizing the dominant terms in the Ra budget of the bay

Ra isotopes are a powerful tool for quantifying the flux of submarine groundwater discharge (SGD) into the sea. Previous studies of ²²³Ra and ²²⁴Ra mass balances in coastal embayments have shown that the Ra balance is dominated by supply via SGD, exchange with the open ocean and radioactive decay. The current study shows that a single time series over a tidal cycle at the principal inlet to Great South Bay (NY, US) is sufficient to determine the net flux of Ra across the inlet, and also can be used to estimate the decay of short-lived Ra in the bay. Estimates of the net Ra flux obtained from a single tidal time-series by using three different approaches agree with those determined from a more time-consuming survey of Ra within the bay, and may represent a first step of estimating SGD in bays and coastal lagoons.     

载铁活化天然沸石处理高氟地下水

采用氯化铁改性天然沸石进行地下水除氟效果的研究,考察了地下水中4种阴离子Cl-、HCO3-、SO24-和PO34-对该改性沸石除氟效果的影响,并分析了其除氟机理和表面成分。研究结果表明,对于初始氟浓度不同的水样,随着阴离子浓度的增加,吸附剂对氟的去除率逐渐下降。Cl-对吸附剂除氟效果影响较小,氟去除率降低较慢;随着HCO3-浓度的增大(由100 mg/L到1 000 mg/L),水样pH由8.42缓慢升高到9.52,而氟去除率则由70.36%缓慢下降到56.73%(2mg/L);SO24-及PO34-对改性沸石除氟效果影响较大,氟去除率降低较快,且PO34-的影响大于SO24-。可以得到载铁活化天然沸石对4种阴离子的吸附顺序为:PO34->SO24->HCO3->Cl-。     

流域地下水质评价的GIS与模型集成分析

流域水环境管理已经成为当今环境科学的一个重要研究对象，对流域规模的水资源可持续管理和战略环境评价，地下水质评价是其重要内容，急需方法学的支持。全面分析目前国内外GIS与模型集成的研究现状，论述GIS与综合指数模型和机理模型集成的所需条件、优势和存在的问题。强调集成中应对模型的特征、模型的输入输出要求、流域数据基础以及GIS软件的功能进行具体分析，否则将导致区域分析的误差加大甚至产生错误信息。结合地下水水质评价常用的指数模型和机理模型，提出了GIS与模型的集成框架，分析GIS在集成中的3种模式，指明GIS与模型集成的发展方向。最后基于GIS与模型集成的现存问题提出对策，得出GIS与综合指数模型和机理模型集成的最优方法及适用条件，为具体应用提供方法学指导。     

LEACHATE LEAKAGE FROM LANDFILLS WITH MODERN LINER SYSTEMS1

ABSTRACT: Recent technological advances have led to a new generation of landfill liner systems that are highly effective at intercepting and removing leachate. Many of the modern liner systems are so effective that they allow very little or no leakage. Indeed, the amount of leakage through those liners is so minimal that, although it can be theoretically predicted, it cannot be measured with the available monitoring well technology. In addition to being highly effective, some modern liner systems are constructed with two liner layers separated by a drainage medium that detects and removes any leakage through the top liner. These significant improvements in liner system technology have led to the questioning of the necessity for the currently required high number of monitoring wells. Reduction of the number of the monitoring wells and/or of the frequency of sampling would result in substantial cost savings. The present study reports the results of a research project conducted at eleven municipal landfills with modern liner technology throughout the State of Florida. Through actual field data and computer modeling, it was found that the liner systems standards applied in the State of Florida are very effective at preventing any groundwater contamination. Thus, the present monitoring well regulations are too conservative.     

北京市农作物虚拟水含量分布

采用灌溉定额法对北京市各区县粮食虚拟水含量和蔬菜虚拟水含量历年的分布进行了计算和分析,并将其与北京市地下水资源分布和开采状况进行了现状对比.结果表明:①各区县粮食虚拟水含量总体上均呈下降趋势,但延庆县的粮食生产会给当地地下水资源带来较大的压力;②顺义区、大兴区,平谷区蔬菜历年的虚拟水含量总体呈增长趋势,在全市蔬菜虚拟水总量中所占的比例依次逐渐增大,而海淀区、丰台区、朝阳区蔬菜历年的虚拟水含量在全市所占的比例呈逐渐减小趋势;③北京地区历年的粮食虚拟水含量总和整体呈现下降趋势,蔬菜虚拟水含量总和略呈增长趋势,但是二者虚拟水含量的总和呈现下降趋势,这与北京市近年来的农业种植结构调整政策是相符合的.     

Sensitivity of key factors and uncertainties in health risk assessment of benzene pollutant

Predicting long-term potential human health risks from contaminants in the multimedia environment requires the use of models. However,there is uncertainty associated with these predictions of many parameters which can be represented by ranges or probability distributions rather than single value.Based on a case study with information from an actual site contaminated with benzene,this study describes the application of MMSOILS model to predict health risk and distributions of those predictions generated using Monte Carlo techniques.A sensitivity analysis was performed to evaluate which of the random variables are most important in producing the predicted distributions of health risks.The sensitivity analysis shows that the predicted distributions can be accurately reproduced using a small subset of the random variables.The practical implication of this analysis is the ability to distinguish between important versus unimportant random variables in terms of their sensitivity to selected endpoints.This directly translates into a reduction in data collection and modeling effort.It was demonstrated that how correlation coefficient could be used to evaluate contributions to overall uncertainty from each parameter.The integrated uncertainty analysis shows that although drinking groundwater risk is similar with inhalation air risk,uncertainties of total risk come dominantly from drinking groundwater route.Most percent of the variance of total risk comes from four random variables.     

沈阳市地下水水质污染特征及变化趋势分析

沈阳市具有良好的供水水文地质条件,按区域水文地质条件及沈阳市农业区划的要求,可划为四个水利分区.由于地下水资源的采补失调和严重过量开采,沈阳市中心城区形成了较大面积的地下水超采漏斗,由西部和东部两大超采区组成.2001年,沈阳市地下水水位呈下降趋势,到2005年,全市枯水期超采漏斗分布面积有所缩小,丰水期地下水超采漏斗分布面积有所增大."十五"期间,沈阳市的地下水水质仍是以"三氮"污染为主,同时存在着铁、锰超标现象."三氮"污染主要集中在浑河流域.各主要污染物在2001-2005年期间变化稳定,趋于平稳.