太湖西岸宜兴城市水系污染物时空分布特征

选用2011—2014年宜兴市12个监测断面21个水质指标的连续监测数据,解析太湖西岸宜兴城市水系污染物的时空分异特征及影响因素。结果表明,宜兴市城区及入太湖河流污染严重,86.05%以上时段内处于劣Ⅴ类水平,特征污染物为TN、NH3-N、BOD5、TP、COD和Hg。污染物空间分异程度大小依次为:AR-OHNH3-NHgTPCODBOD5F-oil=CODMnLASTNDO。不同区域河流污染物浓度随时间变化基本一致,有机物夏季波动较大主要受温度和降雨的双重影响,TN和NH3-N浓度标线出明显的季节变化:春季冬季夏季秋季,Hg、LAS、AR-OH表现出瞬时排放特性,且主要发生在年初。由分析可得,土地利用强度和方式是影响宜兴市城区及入湖河流污染物分布特征的最主要因素,其次是污染来源、河道类型等的影响,表现为城市核心区、三氿入湖区和西北入湖区污染程度依次增大,但差异水平不明显,西南入湖区则相对较轻。     

疏浚对巢湖双桥河水环境容量的影响

双桥河是巢湖受污染较为严重的入湖河流之一,其入湖口距巢湖市自来水厂取水口仅500 m,同时也是巢湖市的主要行洪河道,为了改善水质状况并提高河道行洪能力,于2010年3—5月对双桥河进行了疏浚。本文作者于2009年12月—2010年10月对双桥河监测断面及排污口进行了监测,在分析双桥河水质及现有污染源的基础上,选择CODMn、TP、NH3-N和TN作为水质敏感参数,对疏浚前后双桥河的不同河段污染物质的水环境容量进行了模拟计算,并调查了水生植被覆盖度及沉积物氮磷含量的变化。结果表明,疏浚后整个河道水生植被的覆盖度由40%降低到5%左右,各污染物的降解系数都有较大程度的降低,同时疏浚后短期内CODMn和TP的环境容量均有一定程度的降低,而NH3-N和TN的环境容量变化较小。分析认为,这一方面是由于疏浚后河道内水生植物覆盖度的降低导致水体的自净能力降低,另一方面是由于疏浚过程中的扰动引起大量沉积物的再悬浮及污染物的释放。所以在减少外来污染的前提下,对重富营养化水体底泥进行疏浚并开展水生植被恢复工程应是控制富营养化的有效途径。     

生态修复综合技术在杭州虾龙圩河的应用

杭州虾龙圩河由于多年污染，河道水质严重黑臭，自净能力遭到破坏。本研究通过综合利用底泥污染物削减、生物接触氧化水质净化、造流曝气及水生生态系统修复等技术对虾龙圩河进行治理。结果显示，此项综合技术对城市河流污水具有良好的污染物去除性能，COD、NH3-N和TP的去除率分别可达到73．3％、80．1％和81．7％。通过1年的运行与养护，虾龙圩河治理段的水质、生态环境等有了明显改善，没有发生过水华及黑臭现象，河道水体具备了较强的自净能力。     

北海市水环境容量核算与分区总量控制对策研究

水环境容量核算是城市水环境管理的基础。分析了北海市水环境特征的现状,通过划分陆域控制单元和对应水环境容量核算单元,根据设计水文条件及功能区水质目标等参数,综合选用一维河流非感潮河段容量计算模型、一维河流感潮河段容量计算模型核算了北海市各主要流域地表水水系的水环境容量。在此基础上,结合近海海洋环境容量,核算各控制单元点、面源负荷排放量,分析了北海市基于控制单元分区的可利用水环境容量空间分布特征,并提出了容量资源分区控制利用对策建议。     

污泥水解酸化过程中污染物的释出及其影响因素研究

为了回收利用污泥中的有机物、氮和磷，研究了将厌氧污泥接种到吸附了污染物质的剩余污泥中，对污泥水解酸化的促进以及污泥中微生物所摄取污染物质的释出规律；揭示了厌氧条件下发酵时间、污泥量、pH和热处理对污染物释出的影响。结果表明，接种24 h后污染物被大量释放出来；在发酵时间为24 h条件下，污染物释出量与污泥质量成正比；吸附了污染物的剩余污泥相对含量越高，释磷量越大；污泥厌氧发酵时，碱性条件下有机物和正磷酸盐的释出量大于酸性条件，加碱调高pH可有效促进氨氮的释出；对吸附了污染物的剩余污泥进行短时热处理可有效缩短其厌氧发酵时污染物的释出时间。结果表明，控制污泥厌氧水解发酵条件可以促进污染物的释出，有利于下一步的回收。     

重庆市重污染次级河流伏牛溪水污染控制与水质改善

针对重庆市部分次级河流耗氧污染物负荷高、水动力学弱化、河流生态系统退化等问题,选取重庆市典型次级河流伏牛溪为研究对象,以水质目标管理为指导思想,开展重污染河流水污染控制与水质改善研究。以V类水为水质目标,通过划分治理单元,开展河流水环境容量核算,分别提出基于现状条件、规划用地及上游补水2种情景下的污染负荷削减计算;根据削减负荷分配的结果,提出各个治理单元的污染负荷削减目标与治理措施,并开展目标可达性分析。治理工程实施后,重庆市伏牛溪水体中主要污染物的平均浓度及年达标率满足考核要求,该方案为我国山地城市重污染河流的水环境治理提供很好的参考。     

模糊综合评价在天然水体水质评价中的应用研究

采用模糊数学方法，对河网地区面源污染影响较大的代表性河流的水质状况进行综合评价研究。根据监测断面水质污染特点，确定了8个指标作为评价因子，建立了评价因素矩阵，计算出影响因子的权重。在此基础上，提出了模糊综合评价的水质级别，证明该河网地区的污染物主要是氮、磷和有机物。     

模糊综合评价在天然水体水质评价中的应用研究

采用模糊数学方法,对河网地区面源污染影响较大的代表性河流的水质状况进行综合评价研究。根据监测断面水质污染特点,确定了8个指标作为评价因子,建立了评价因素矩阵,计算出影响因子的权重。在此基础上,提出了模糊综合评价的水质级别,证明该河网地区的污染物主要是氮、磷和有机物。     

常熟河网区水污染物总量控制研究

基于常熟河网原型调水实验和水功能区划，建立了感潮地区河网水量水质模型，对常熟河道水质降解系数及水环境容量进行了计算，并按照点源和面源对区域内污染源进行统计，在此基础上进行了常熟河网水污染物总量控制值和现状削减量的计算，为该地区的水污染防控提供了科学依据。     

玄武湖入湖口的悬浮颗粒物沉降调查研究

通过对玄武湖的外围入湖口及湖心的悬浮颗粒物的组成、悬浮颗粒物沉降量及沉降速率的对比实验，阐述了外源水、面源水的污染物对湖水水质的影响，并从面源、点源、水体自净能力及补给水等，促使湖水水质变化的途径入手，依据各项监测结果及对数据的分析，找出了玄武湖多次发生水污染的原因是多方面、多途径的影响结果。从监测分析发现，入湖口悬浮颗粒物沉降量高于湖心点，说明玄武湖水污染主要是受外源影响。另外还发现，入湖污水经水生植物阻滞、吸附和吸收后，其悬浮颗粒物的沉积速率和沉降量明显增大，据此认为，控制外源性污染、补充清洁水及在入湖口周围广种水生植物，是减缓湖水水质恶化，促使水质改良的有效途径。     

面向城市水系环境需水的再生水空间配置——以深圳市宝安区为例

以深圳市宝安区为例,探讨以再生水满足城市水系环境需水的方法.应用一维恒定与非恒定水质模型计算了4种补水水质方案下该区10条主要河流的环境需水量,从水量平衡角度提出全区再生水BOD5的平均值,并进一步分析了补水水质与河流环境需水量的关系.结合该区水系与污水处理系统空间位置,提出3种再生水的空间配置方法.结果表明:茅洲河和...     

Conservative heavy metal total discharge schemes

Currently, according to Taiwan’s Water Pollution Control Act, the environmental control of waterbodies and water quality depends on the effluent standards and the standard of water quality in the rivers. The Act demands that each stationary pollution source comply with the effluent standard before being discharged into the rivers, and that the overall water quality in the river shall not exceed the declared standard of water quality. To improve the condition of the waterbodies and water quality of the rivers, the Environmental Protection Administration (EPA) in Taiwan has made stricter regulations concerning the discharge standard. Such regulations will help to reduce the weight of individual pollutants discharged; the discharged wastewater, however, will still gradually worsen the water quality of the rivers even after complying with the effluent standard since some of the pollutant dischargers may decrease the concentration of pollutants by diluting the water before discharging; thus, the total weight of metals discharged in the rivers will not be reduced, and the water quality in the areas where the pollutant sources are concentrated will not thereby be significantly improved. To protect the irrigation water and farmlands from being polluted by discharged heavy metals in industrial wastewater, the EPA started controlling the sources in accordance with the total quantity control (TQC) as defined in the Water Pollution Control Act, in the hope of perfecting the environmental protection of waterbodies and water quality, as well as ensuring clean water sources without any pollution for the rivers, land, and people.     

象山港网箱养殖对海域环境的影响及其养殖环境容量研究

以象山港海域的潮流模型和物质输运模型为基础,建立了各网箱养殖区的氮、磷污染物排放量与研究海域水质之间的响应关系,对该海域的养殖污染状况进行了模拟,讨论了该海域的网箱养殖环境容量.结果表明,象山港内的氮、磷浓度在养殖区密集的港顶海域超出一类水质标准;该海域的氮、磷养殖环境容量分别为670.74t/a和77.32t/a.目前,象山港内各网箱养殖区的污染物排放量已超出其容量,需进行削减.     

Pharmaceuticals on a sewage impacted section of a Mediterranean River (Llobregat River,NE Spain) and their relationship with hydrological conditions

Introduction  

Mediterranean rivers are characterized by a high flow variability, which is strongly influenced by the seasonal rainfall. When water scarcity periods occur, water flow, and dilution capacity of the river is reduced, increasing the potential environmental risk of pollutants. On the other hand, floods contribute to remobilization of pollutants from sediments. Contamination levels in Mediterranean rivers are frequently higher than in other European river basins, including pollution by pharmaceutical residues. Little attention has been paid to the transport behavior of emerging contaminants in surface waters once they are discharged from WWTP into a river. In this context, this work aimed to relate presence and fate of emerging contaminants with hydrological conditions of a typical Mediterranean River (Llobregat, NE Spain).     

Antibiotic resistance genes in an urban river as impacted by bacterial community and physicochemical parameters

Antibiotic resistance genes (ARGs) in urban rivers are a serious public health concern in regions with poorly planned, rapid development. To gain insights into the predominant factors affecting the fate of ARGs in a highly polluted urban river in eastern China, a total of 285 ARGs, microbial communities, and 20 physicochemical parameters were analyzed for 17 sites. A total of 258 unique ARGs were detected using high-throughput qPCR, and the absolute abundance of total ARGs was positively correlated with total organic carbon and total dissolved nitrogen concentrations (P < 0.01). ARG abundance and diversity were greatly altered by microbial community structure. Variation partitioning analysis showed that the combined effects of multiple factors contributed to the profile and dissemination of ARGs, and variation of microbial communities was the major factor affecting the distribution of ARGs. The disparate distribution of some bacteria, including Bacteroides from mammalian gastrointestinal flora, Burkholderia from zoonotic infectious diseases, and Zoogloea from wastewater treatment, indicates that the urban river was strongly influenced by point-source pollution. Results imply that microbial community shifts caused by changes in water quality may lead to the spread of ARGs, and point-source pollution in urban rivers requires greater attention to control the transfer of ARGs between environmental bacteria and pathogens.

     

Evaluation of fecal pollution of river sediment by detection of urobilin

In this study, we attempted to establish a new indicator for fecal pollution of river sediment using a sensitive detection method for urobilin. Urobilin contained in sediment was extracted with an alkaline buffer solution. The suitable buffer solution for extraction of urobilin consisted of 0.1 M Tris-HCl buffer (pH 10.0) containing 0.1 m sodium chloride. The ratio of sediment to buffer was 1:10. The distribution of urobilin in river sediment was studied by this method. The amount of urobilin in the river sediment of Tokyo (urban) and the Miura peninsula (rural) area was surveyed. Large quantities of urobilin were detected in the sediments of the urban rivers, but it was scarce in the rural rivers. Urobilin showed a higher content in sediment than in water. Urobilin in river sediment is distributed in large amounts in the lower reaches, where the water is polluted with domestic sewage and industrial waste, but is scarce in the upper streams. The amount of urobilin decreases to the lower layers.     

Urban nonpoint source pollution buildup and washoff models for simulating storm runoff quality in the Los Angeles County

Many urban nonpoint source pollution models utilize pollutant buildup and washoff functions to simulate storm runoff quality of urban catchments. In this paper, two urban pollutant washoff load models are derived using pollutant buildup and washoff functions. The first model assumes that there is no residual pollutant after a storm event while the second one assumes that there is always residual pollutant after each storm event. The developed models are calibrated and verified with observed data from an urban catchment in the Los Angeles County. The application results show that the developed model with consideration of residual pollutant is more capable of simulating nonpoint source pollution from urban storm runoff than that without consideration of residual pollutant. For the study area, residual pollutant should be considered in pollutant buildup and washoff functions for simulating urban nonpoint source pollution when the total runoff volume is less than 30 mm.     

Material flow analysis of pollutants in Taiwan

We present a material flow analysis (MFA) of biological oxygen demand (BOD5) and suspended solids (SS) in estuaries located on the northern and southern coasts of Taiwan. Using data from 1992–2000, we examine human economic activities in each watershed to predict associated pollutant flows. This estimate is compared to data collected at monitoring stations. The ratio allows us to calculate each river system's ability to assimilate and decompose these pollutants, its self-purification capacity. Our results show that over six times as much BOD5 reaches the northern estuary from the urban watershed that in the south. More SS reaches the southern estuary than the north due to more intense land disturbance. Trends for pollutant flows to the northern estuary threaten its capacity to meet sustainability criteria. Trends in the south show a receding threat. We suggest management objectives to enhance prospects for sustaining environmental quality in these two critical regions.     

利用生态混凝土控制城市坡面暴雨径流污染试验研究

利用生态混凝土作为护坡材料,研究暴雨条件下生态混凝土控制山坡降雨径流污染的机理,以期对生态混凝土在城市护坡和护岸中的应用提供理论依据.研究结果表明,生态混凝土改变了雨水在坡面上的水文过程,阻延径流作用十分明显,有效地降低了污染物的负荷输出.生态混凝土试验小区(T2)与裸地(CK)和改良土壤小区(T1)相比,径流量分别减少了48%和24%,TN年度污染负荷(UPLRs)分别减少了53%和45%,溶解态氮(DN)减少了26%和28%,TP减少了57%和30%,溶解态磷(DP)降低了80%和33%,COD降低了62%和40%,TSS降低了56%和43%,产流时间和流量峰均明显滞后.另外,同植被覆盖良好的小区(T3)相比,生态混凝土对各种污染指标的控制效果没有明显差异,但其抗冲刷能力较强,更能适应城市护坡和护岸的需要.     

粤西某市小容量河流水污染综合控制研究

对粤西某石化城河段几种主要污染物进行了容量计算 ,发现即使工业污染源全部达标 ,其水质状况与目标的差距仍较大 ,据此提出小容量河流的观点。为保护水环境 ,结合流域实际情况 ,本文提出改变以往单纯依靠工业污染源达标控制手段 ,而采用多手段相结合的综合管理模式来改善水环境的观点 ,并以中长期水环境规划年内目标值为依据 ,分析了本方法的有效性、经济性和可操作性 ,由此对其他具相似条件小容量河流的城市水环境管理起到借鉴性作用。