改进的有限单元法在河流水质数值模拟中的应用

利用有限单元法进行二维水质模拟不用考虑河流速度和流量分布等资料,可以直接根据河床地形特点求出水质分布.但传统方法需要利用作图法求出累积流量曲线,是整个模拟过程中最耗人力物力的过程.为解决这一问题,探讨了拉格朗日插值法在复杂河段二维水质模型数值计算中的应用,运用该方法对三峡长寿段的排污口对干流影响进行了数值计算,并将计算结果与作图法的结果进行了比较,比较结果验证了该方法具有省时、高效的优点,具有更加广阔的应用前景.     

直接投菌法在城市重污染河流治理中的应用研究

在无截污和清除内源的情况下,对深圳市甘坑河采用梅花式接种法将本源微生物菌剂分两次直接接入河流水体及底泥中。结果表明,第1次接种后的4 d内各项水质指标都不稳定,4 d后,悬浮物、COD、TP和NH3-N等浓度下降,水质明显改善;但从第8天开始,COD、NH3-N和TP的去除率同时下降,本源微生物的处理效率开始降低,需进行第2次接种;第2次接种后,DO浓度提升至2.0 mg/L以上,COD、TP和NH3-N的去除率分别保持在40%、30%和40%以上。结果表明,直接投菌法在城市重污染河道治理中可以初步消除河道的黑臭现象,修复水质。     

污染防治微生物制剂在城市河流污染控制中的应用及其生物安全

简要论述了污染防治微生物制剂的概念和在城市河流污染控制中的应用,并介绍了国外对微生物制剂的风险评估和对污染防治微生物制剂的管理方式,提出了国内应优先开发本土的天然的污染防治微生物制剂的建议,尽快发展中国环境微生物技术.     

TiO2光催化氧化技术的研究及其在污染治理中的应用

探讨了TiO2光催化氧化技术的机理及其在空气净化、水处理、抗菌防污中的应用,指出了目前研究中存在的一些问题和解决办法.     

有机物污染综合指数在水源水质评价中的应用

在对两自来水公司水源水进行为期１年的水质检测基础上，采用水质类别法和有机污染物综合指数法对各点水源水质进行评价，其结果两种评价方法得出一致的结论，综合指地能直接反映水体受污染的性质和程度，在基层单位具有实用性。     

Fenton法及其在废水处理中的应用研究

Fenton法在处理难降解有机污染物时具有独特的优势．是一种很有应用前景的废水处理技术。文章介绍了该技术的发展过程、主要类型及应用状况,并对其在废水处理中的优势．存在问题和发展趋势作出评述。     

神经网络在次级河流回水区叶绿素a浓度预测中的应用

以长江次级河流之一的临江河为研究对象,探讨神经网络应用于次级河流回水区叶绿素a浓度短期预测的可行性。利用主成分分析法（PCA）选取对叶绿素a浓度影响较大的指标,在这些指标数据的基础上建立RBF神经网络模型。网络训练和测试的结果表明,模型模拟精度较高,说明RBF神经网络模型可以用于次级河流回水区叶绿素a浓度的短期预测。通过对临江河回水区叶绿素a影响因子的分析,表明控制水体中磷含量应是临江河回水区富营养化防治的重点。     

吹扫—捕集法在挥发性有机污染物分析中的应用

吹扫－捕集法为20世纪70年代中期推出的痕量挥发性有机化合物的富集方法，它具有简便，灵敏度高，富集率高，快速，精密，准确，不使用有机溶剂等特点，20多年以来，吹扫－捕集器和GC、GC／MS等仪器联用测定环境中痕量挥发性有机污染物，已获得令人满意的结果，因而吹扫－捕集法将在有机污染分析中得到日益广泛的应用。     

原位化学氧化法在土壤和地下水修复中的研究进展

综述了原位化学氧化法修复污染土壤及地下水的最新进展，着重介绍了几种氧化剂，如二氧化氯、双氧水及Fenton试剂、高锰酸钾和臭氧在土壤修复中的应用、不足及改进，并对化学氧化修复技术的发展前景进行了展望。     

Development and Application of a Three-Dimensional Finite Element Vapor Intrusion Model

Abstract

Details of a three-dimensional finite element model of soil vapor intrusion, including the overall modeling process and the stepwise approach, are provided. The model is a quantitative modeling tool that can help guide vapor intrusion characterization efforts. It solves the soil gas continuity equation coupled with the chemical transport equation, allowing for both advective and diffusive transport. Three-dimensional pressure, velocity, and chemical concentration fields are produced from the model. Results from simulations involving common site features, such as impervious surfaces, porous foundation sub-base material, and adjacent structures are summarized herein. The results suggest that site-specific features are important to consider when characterizing vapor intrusion risks. More importantly, the results suggest that soil gas or subslab gas samples taken without proper regard for particular site features may not be suitable for evaluating vapor intrusion risks; rather, careful attention needs to be given to the many factors that affect chemical transport into and around buildings.     

高位铁皮水箱供水质量及影响因素

我们于１９９５年３月￣４月调查了武汉市高位铁皮水箱的供水质量。结果表明：高层住宅水箱近年虽曾清洗消毒，但高层用户龙头水及水箱水中游离性全氯未达标比例较大，分别为７３．３％和６６．７％。个别底层住户水样中铁超标。高位水箱水样中细菌总数超标比例为２０％。反映了高层住宅二次供水中在水的输送、贮存过程中有二次污染存在。经水样监测指标相关性和灰色关联性分析，认为游离性余氯可作为常规监测高层住宅二次供水质量的     

数值仿真在钱塘江引水入城工程水质预测中的应用

使用二维浅水波方程及传质模型,对工程前期排人钱塘江的废水中污染物的传播及分布进行预测,其预测结果可为工程排污口附近钱塘江水质保护对策制定提供依据。     

改进的QGA-BP模型在弥苴河总氮量预测中的应用

水质预测对水环境规划、评价和管理十分重要。构建一种改进的量子遗传算法（QGA）优化BP神经网络的模型,即在量子遗传算法中引入了旋转角的动态改进策略和遗传算法的交叉变异操作,并以改进的QGA作为进化操作准则优化BP模型的权值和阈值。以弥苴河复杂水环境水质预测为实例,选取一组历史观测数据作为训练样本,对其进行分析。将结果与BP模型、QGA-BP模型仿真结果进行了对比,改进后的QGA-BP模型在进化代数、收敛速度和预测结果的准确率有较大提高。对弥苴河水质的预测结果表明,将改进QGA-BP模型用于水质预测是可行、有效的预测方法。     

Drivers influencing adaptive management: a retrospective evaluation of water quality decisions in South East Queensland (Australia)

This article analyzes interviews with natural resource managers in South East Queensland (SEQ), Australia. The objectives of the research are (i) to apply and test deductive/inductive text analysis methods for constructing a conceptual model of water quality decision-making in SEQ, (ii) to understand the role of information in the decision-making process, and (iii) to understand how to improve adaptive management in SEQ. Our methodology provided the means to quickly and objectively explore interview data and also reduce potential subjective bias normally associated with deductive text analysis methods. At a more practical level, our methodology indicates potential intervention points if one is to influence the decision-making process in the region. Results indicate that relevant information is often ignored in SEQ, with significant consequences for adaptive management. Contextual factors (political, social, and environmental) together with effective communication or lobbying strategies often prevent evidence-based decisions. We propose that in addition to generating information to support decisions, adaptive management also requires an appraisal of the true character of the decision-making process, which includes how stakeholders interact, what information is relevant and salient to management, and how the available information should be communicated to stakeholders and decision-making bodies.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0537-4) contains supplementary material, which is available to authorized users.     

Constructed wetlands as a component of the agricultural landscape: mitigation of herbicides in simulated runoff from upland drainage areas

Constructed wetlands are a recommended practice for buffering pollutant source areas and receiving waters. A wetland consisting of a sediment trap and two treatment cells was constructed in a Mississippi Delta lake watershed. A 3-h simulated runoff event was initiated (2003) to evaluate fate and transport of atrazine and fluometuron through the wetland. Water samples were collected during a runoff simulation and then afterward at selected intervals for 21 d, and analyzed for the herbicides. Breakthrough patterns for herbicide concentrations in water samples during the first 20 h after simulated runoff showed peak concentrations in the first 6 h, with gradual tailing as the herbicide pulse was diluted in the second, excavated (deeper) cell. Atrazine and fluometuron concentrations in the first (shallower, non-excavated) cell averaged 12- and 20-fold greater, respectively, than those in the second cell following simulated runoff, indicating entrapment in the first cell. Atrazine and fluometuron concentrations in the shallower cell decreased 32% and 22%, respectively, 9 d following simulated runoff, indicating either degradation or sorption to soil or wetland flora. In the excavated cell, concentrations were even lower, and atrazine declined more rapidly than fluometuron. Results indicate constructed wetlands can improve downstream water quality though sequestration or processing of pollutants.     

可拓学理论在水质量综合评价中的应用研究

在物元理论、可拓集合论和关联函数计算的基础上 ,利用物元分析理论的特点建立了水质量评估模型 ,把水质量评估由定性转化为了定量。通过实际水质量等级的关联度计算 ,对北京永定河水质量进行了可拓学评价 ,评价结果表明了该方法的可应用性     

Investigating the sources of the mutagenic activity found in a river using the Salmonella assay and different water extraction procedures

In the routine São Paulo state (Brazil) surface water quality-monitoring program, which includes the Salmonella microsome mutagenicity assay as one of its parameters, a river where water is taken and treated for drinking water purposes has repeatedly shown mutagenic activity. A textile dyeing facility employing azo-type dyes was the only identifiable source of mutagenic compounds. We extracted the river and drinking water samples with XAD4 at neutral and acidic pH and with blue rayon, which selectively adsorbs polycyclic compounds. We tested the industrial effluent, raw, and treated water and sediment samples with YG1041 and YG1042 and compared the results with the TA98 and TA100 strains. The elevated mutagenicity detected with YG-strains suggested that nitroaromatics and/or aromatic amines were causing the mutagenicity detected in the samples analyzed. Positive responses for the blue rayon extracts indicated that mutagenic polycyclic compounds were present in the water samples analyzed. The mutagen or mixture of mutagens present in the effluent and water samples cause mainly frameshift mutations and are positive with and without metabolic activation. The Salmonella assay combined with different extraction procedures proved to be very useful in the identification of the origin of the pollution and in the identification of the classes of chemical compounds causing the mutagenic activity in the river analyzed.     

D型滤池在成都沙河污水处理厂深度处理中的应用

成都沙河污水处理厂二沉池出水进行深度处理的过滤单元采用德安公司研制开发的D型滤池.其核心技术是采用DA863彗星式纤维滤料作为内部填料,该填料具有过滤精度高、滤速快、自适应等特点,可进行直接过滤.对D型滤池内部结构、功能和运行工艺参数等作了较为详细的介绍.通过实际运行,D型滤池的出水SS小于10 mg/L,达到了设计要求.     

南苕溪支流锦溪水质时空变化特征分析

综合运用灰色聚类法、综合污染指数法、等级聚类法就南苕溪支流锦溪近年水质时空变化特征进行分析。结果表明,锦溪入青山水库断面水质2005—2009年逐年改善,2007年后达到灰色聚类等级Ⅲ类水质要求;2009年秋季至2010年夏季期间秋、冬两季的污染程度高于春、夏季节;枯水期综合污染指数最高,但TN、TP污染分指数在丰水期最高,表明污染源中面源污染已占相当比例。空间变化方面从玲珑桥到江桥锦溪水质的综合污染指数不断提升,到江桥时达到极值13.25,锦溪末端三眼桥断面水质较江桥断面有所改善;SPSS空间聚类分析可分为轻污染区(从玲珑桥到冬韵桥)、重污染区(从群利桥到江桥)和中度污染区(从江桥到三眼桥)。锦溪上游农业区对河水中的COD、TN和TP的贡献率分别为66%、54%和49%,农业面源污染已成为制约锦溪水质改善的主要因素。