Synthesis of Sulfonated Naphthalene-Formaldehyde Condensates and their Trace-analytical Determination in Wastewater and River Water

Naphthalenesulfonates and their condensates with formaldehyde (SNFC) are widely used in industrial processes, e.g. as plasticizers for concrete or as tanning agents. Based on their high aqueous solubility these compounds are expected to be eliminated incompletely in mechanical-biological treatment plants and to end up in the aquatic environment. Due to the lack of reference compounds the identification and quantification of these condensates in the aquatic environment was impossible in the past. This paper describes the synthesis of several condensates of 2-naphthalenesulfonate with formaldehyde. With the synthesized products as reference compounds it was possible for the first time to detect and quantify some sulfonated naphthalene-formaldehyde condensates in the aquatic environment. For this purpose characteristic peaks in the HPLC screening of wastewater and river water samples were compared with the corresponding peaks of a technical SNFC product. Three out of several paths on which these compounds enter the aquatic environment were identified. The identified compounds in the analyzed wastewater samples have concentrations between 0.14 and 110 μg/L.     

Estrogen equivalent concentration of individual isomer-specific 4-nonylphenol in Ariake sea water, Japan

Concentrations of 4-nonylphenol (NP) were determined by isomer-specific quantification of individual NP isomers based on relative response factor (RRF) quantification with GC–MS in combination with steam distillation extraction. Concentrations of NP in the Ariake Sea decreased with distance from the river mouth (St.A; 49 ng NP/l) to offshore areas (St.C; 11 ng NP/l). Even the least concentration in water from St.C in Ariake Sea was sufficient to have adverse effects on barnacles. The isomers, NP1–NP14 were separated by GC–PFC and identified structurally with NMR. The isomers varied in estrogenic activity with NP7 exhibiting the greatest estrogenic activity with a potency that was approximately 1.9 × 10⁻³ that of 17β-estradiol (E2) in recombinant yeast screen system. The coefficient of variation (CV) of NP isomer’s concentrations among three samples at St.A, B and C were 4–75%. This suggests that NP isomers might be independently degraded in aquatic environmental samples. The predicted estrogenic activity of measured concentrations of NP in Ariake Sea was 2.7–3.0-fold greater than the measured estrogen agonist activity.     

巢湖流域双桥河底泥疏浚对浮游甲壳动物群落结构的影响

为研究河流底泥疏浚工程对富营养化河流水生生态系统的影响,选取巢湖双桥河开展为期一年的河流生态监测与调查,对比分析了巢湖双桥河疏浚前和疏浚后的水质指标、浮游甲壳动物群落结构及生物多样性指数.研究发现：底泥疏浚后双桥河水质得到明显改善,其中氮、磷营养盐分别削减48.09%和19.09%;底泥疏浚对浮游甲壳动物群落结构影响显著,疏浚后浮游甲壳动物生物量从1.86 mg/L下降到0.25 mg/L,下降了86.40%;疏浚后生物多样性指数高于疏浚前,且受季节影响较大;浮游甲壳动物与水环境因子相关性研究发现：pH、温度、铵态氮、硝态氮、可溶性氮、总氮和氮磷比对浮游甲壳动物总生物量均有极显著影响.研究结果表明,河流底泥疏浚工程能显著削减水体中氮、磷营养盐,并从一定程度上改善河流浮游甲壳动物群落结构,促进河流水生生态系统向健康、安全的方向发展.因此,对于双桥河这种受城市外源污染影响较大的城市污染型河流,在削减外源营养盐特别是氮输入的条件下,实施底泥疏浚工程可以促进其水生生态系统的修复.     

Estrogen receptor (ER) agonists and androgen receptor (AR) antagonists in effluents from Norwegian North Sea oil production platforms

The in vitro estrogen receptor (ER) agonist and androgen receptor (AR) antagonist potencies of offshore produced water effluents collected from the Norwegian Sector were determined using recombinant yeast estrogen and androgen screens. Solid phase extraction (SPE) concentrates of the effluents showed E2 agonist activities similar to those previously reported for the United Kingdom (UK) Continental Shelf (<0.1-4 ng E2 L(-1)). No activity was detected in the filtered oil droplets suggesting that produced water ER activity is primarily associated with the dissolved phase. Targeted analysis for methyl- to nonyl-substituted alkylphenol isomers show the occurrence of known ER agonists in the analysed samples. For the first time, AR antagonists were detected in both the dissolved and oil associated phase at concentrations of between 20 and 8000 microg of flutamide equivalents L(-1). The identity of the AR antagonists is unknown, however this represents a significant input into the marine environment of unknown compounds that exert a known biological effect. It is recommended that further analysis using techniques such as bioassay-directed analysis is performed to identify the compounds/groups of compounds that are responsible in order to improve the assessment of the risk posed by produced water discharges to the marine environment.     

Distribution of heavy metals in water and sediment of an urban river in a developing country: A probabilistic risk assessment

River water and sediment embody environmental characteristics that give valuable eco-environmental information.Due to rapid industrialization,the aquatic environment of any urban river can be seriously polluted by heavy metals（HMs）.The global concern is caused by heavy metal pollution because of its potential harm to aquatic ecosystems and human health.In the Bhairab River,Bangladesh,surface sediment concentrations of globally alarming toxic metals such as arsenic（As）,chromium（Cr）,cadmium（Cd）,an...     

福建敖江流域水域生态系统健康评估

以敖江流域为研究区,通过采集底栖动物、鱼类等样品,结合监测数据分析流域水域生态系统健康状况,并采用指标体系评估方法对水域生态系统进行评估.结果表明:敖江流域水质总体良好,但山仔水库总氮、总磷浓度长期超标,水体存在富营养化和藻类水华暴发生态环境问题;底栖动物种类呈现支流多于干流、河流多于水库的规律;鱼类种类上、中、下游各科物种组成差异不显著,鱼类区系特点具有较明显的热带、亚热带区系特点;流域上游、中游水域生态健康良好,下游水域生态健康一般.     

In situ measurements of fine sediment infiltration (FSI) in gravel-bed rivers with a hydropeaking flow regime

The overpresence of fine sediment and fine sediment infiltration (FSI) in the aquatic environment of rivers are of increasing importance due to their limiting effects on habitat quality and use. The habitats of both macroinvertebrates and fish, especially spawning sites, can be negatively affected. More recently, hydropeaking has been mentioned as a driving factor in fine sediment dynamics and FSI in gravel-bed rivers. The primary aim of the present study was to quantify FSI in the vertical stratigraphy of alpine rivers with hydropeaking flow regimes in order to identify possible differences in FSI between the permanently wetted area (during base and peak flows) and the so-called dewatering areas, which are only inundated during peak flows. Moreover, we assessed whether the discharge ratio between base and peak flow is able to explain the magnitude of FSI. To address these aims, freeze-core samples were taken in eight different alpine river catchments. The results showed significant differences in the vertical stratification of FSI between the permanently wetted area during base flow and the dewatering sites. Surface clogging occurred only in the dewatering areas, with decreasing percentages of fine sediments associated with increasing core depths. In contrast, permanently wetted areas contained little or no fine sediment concentrations on the surface of the river bed. Furthermore, no statistical relationship was observed between the magnitude of hydropeaking and the sampled FSI rate. A repeated survey of FSI in the gravel matrix revealed the importance of de-clogging caused by flooding and the importance of FSI in the aquatic environment, especially in the initial stages of riparian vegetation establishment. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.     

Distribution and characterization of in‐channel large wood in relation to geomorphic patterns on a low‐gradient river

A 177 river km georeferenced aerial survey of in‐channel large wood (LW) on the lower Roanoke River, NC was conducted to determine LW dynamics and distributions on an eastern USA low‐gradient large river. Results indicate a system with approximately 75% of the LW available for transport either as detached individual LW or as LW in log jams. There were approximately 55 individual LW per river km and another 59 pieces in log jams per river km. Individual LW is a product of bank erosion (73% is produced through erosion) and is isolated on the mid and upper banks at low flow. This LW does not appear to be important for either aquatic habitat or as a human risk. Log jams rest near or at water level making them a factor in bank complexity in an otherwise homogenous fine‐grained channel. A segmentation test was performed using LW frequency by river km to detect breaks in longitudinal distribution and to define homogeneous reaches of LW frequency. Homogeneous reaches were then analyzed to determine their relationship to bank height, channel width/depth, sinuosity, and gradient. Results show that log jams are a product of LW transport and occur more frequently in areas with high snag concentrations, low to intermediate bank heights, high sinuosity, high local LW recruitment rates, and narrow channel widths. The largest concentration of log jams (21.5 log jams/km) occurs in an actively eroding reach. Log jam concentrations downstream of this reach are lower due to a loss of river competency as the channel reaches sea level and the concurrent development of unvegetated mudflats separating the active channel from the floodplain forest. Substantial LW transport occurs on this low‐gradient, dam‐regulated large river; this study, paired with future research on transport mechanisms should provide resource managers and policymakers with options to better manage aquatic habitat while mitigating possible negative impacts to human interests. Copyright © 2011 John Wiley & Sons, Ltd.     

Monitoring of toxic substances in the Hong Kong marine environment

A long-term programme for monitoring toxic substances in the marine environment was established in Hong Kong in 2004, focusing on chemicals of potential ecological and health concern. The programme ran on 3-year cycles, with the first two years monitoring marine water, sediment, biota, and the third year monitoring pollution sources. Twenty-four priority chemicals were measured, including dioxins/furans, dioxin-like PCBs, total PCBs, PAHs, DDTs, HCHs, TBTs, phenol, nonylphenol (NP), NP ethoxylates, PBDEs and metals. Results from the first three years of monitoring indicate that toxic substances in the Hong Kong marine environment were within the range reported for the coastal waters in China and other regions, but generally lower than in the Pearl River Estuary. The levels met the standards for protecting aquatic life and human consumption. Sewage effluent, stormwater and river water were possible sources of phenolic compounds; whereas air deposition or regional pollution, rather than local discharges, may contribute to the dioxins/furans, PAHs and PCBs found in the marine environment.     

The impact of environmental factors on the distribution pattern of aquatic plants along the Danube River corridor (Slovakia)

The aim of the study was to evaluate pattern of the aquatic macrophyte species distribution along the Danube fluvial corridor in Slovakia, and to identify the impact of environmental abiotic parameters on macrophyte species diversity. Field sampling was performed in the period 1999–2005 from the boat. Aquatic habitats were divided into 365 survey unit (SU). The survey of aquatic macrophytes and abiotic parameters followed the European standard approach EN 144184 2003. The plant mass estimate (PME – a semi-quantitative estimation of the amount of individual species in a SU, which takes into account three-dimensional development of plant stands) was estimated according to a five-point-scale in each SU; environmental pattern, were assessed over six abiotic parameters (river km, bank type, sediment type, flow velocity class, land-use type, and heavily man-modified water bodies). Altogether, four hydrologic connectivity types of aquatic habitats were distinguished: the Danube River, Open Arms, Separated Arms, and Seepage Water-bodies.

In total, 54 aquatic macrophytes were recorded for the whole data set of the Danube fluvial corridor. The PME data of true aquatic macrophytes and the length of SUs created a basis for numerical derivates, relative plant mass (RPM), mean mass indices (MMT, MMO) and the distribution ratio (d).

The results correspond with comparable studies on this topic: the highest macrophytes species diversity occurred in Separated Arms. On the contrary, macrophytes had the lowest richness in the Danube River main channel, although their diversity was slightly higher in heavily man-modified water bodies (such as the hydropower plant's reservoir and the abandoned main channel of the so-called Old Danube). Our results suggest that the lateral connectivity types of the river water bodies, primarily characterised by different hydrologic dynamics and human impact expressed as land-use types are responsible for the variability of aquatic macrophyte assemblages along the Danube corridor in Slovakia.     

Monitoring of toxic substances in the Hong Kong marine environment

A long-term programme for monitoring toxic substances in the marine environment was established in Hong Kong in 2004, focusing on chemicals of potential ecological and health concern. The programme ran on 3-year cycles, with the first two years monitoring marine water, sediment, biota, and the third year monitoring pollution sources. Twenty-four priority chemicals were measured, including dioxins/furans, dioxin-like PCBs, total PCBs, PAHs, DDTs, HCHs, TBTs, phenol, nonylphenol (NP), NP ethoxylates, PBDEs and metals. Results from the first three years of monitoring indicate that toxic substances in the Hong Kong marine environment were within the range reported for the coastal waters in China and other regions, but generally lower than in the Pearl River Estuary. The levels met the standards for protecting aquatic life and human consumption. Sewage effluent, stormwater and river water were possible sources of phenolic compounds; whereas air deposition or regional pollution, rather than local discharges, may contribute to the dioxins/furans, PAHs and PCBs found in the marine environment.     

Biodiversität und Ökologie aquatischer Oomycetes‐Arten im Auesee und in der Fulda in Kassel (Hessen)

Biodiversity and Ecology of Species of Aquatic Oomycetes in the Aue Lake and the River Fulda in Kassel (Hessen) In this study, we record diversity and ecology of aquatic Oomycetes in the Aue Lake and the river Fulda in Kassel (Hesse, Germany). We monthly collected water samples of both water bodies from July 2003 to June 2004. The baiting method was used to gain an insight into the occurrence of aquatic Oomycetes. A total of 14 species of aquatic Oomycetes belonging to the orders Saprolegniales, Leptomitales and Olpidiopsidales could be isolated of both water bodies. Numerous saprophytic isolates of Rhizophydium Schenk (Chytridiomycetes), Rhizophydium carpophilum (Zopf) Fischer, parasitic on Oomycetes, and additionally one species of Plasmodiophoromycetes, Woronina polycystis Cornu could be isolated. Many isolates of Saprolegniales attributable to the genera Achlya Nees, Dictyuchus Leitgeb, Saprolegnia Nees and Pythium Pringsheim (Pythiales), which could only be identified on generic level, could be isolated as well. The species were examined and discussed with respect to their occurrence in the stagnant water Aue Lake and/or in the running water of the river Fulda. Half of the isolated species only occurred in one of the water bodies. In this study the occurrence of Achlya proliferoides Coker could be documented for Germany for the first time. The trophic status of the Aue Lake and of the classification of water quality of the river Fulda were determined by limnological‐chemical parameters obtained by simultaneous investigations of both water bodies.     

A review of ecological restoration techniques in fluvial rivers

Rivers play an important role in people's living and agricultural production, however, intense human activities have broken the original ecological balance, and affected structures and functions of the river ecosystem. To restore the damaged river ecosystem back to a healthy status, effective ecological restoration measures need to be implemented. The main problems that the damaged rivers face are either the locally altered hydrological processes affected by construction of hydraulic facilities, or the deterioration of water quality resulted from pollution emissions, or both. In this study, ecological restoration techniques of the rivers affected by engineering control or pollution are reviewed respec-tively. In addition, three kinds of methods, i.e. physical, chemical and biological–ecological methods are introduced in details for the rivers affected by water pollution. At present, the development of river restoration techniques shows the following trends: 1) the scale of ecological restoration is becoming larger; 2) ecological restoration measures are required to meet multiple objectives; and 3) the man-agement of water environment is changing from water quality management to aquatic ecosystem management.     

From fluvial dynamics to eco-fluvial dynamics

Sediment plays a very important role in the functioning of river ecosystems. It is the basic substance for the survival of benthic animals and aquatic plants. On the other hand, the growth of biofilms and bio-disturbance of benthos affect the sediment transport characteristics. With the increasing attention to protect aquatic ecosystems, the importance of habitats has become increasingly researched. The need to study the interactions among sediment, flow, riverbed deformation, and aquatic ecosystems naturally leads to the proposed discipline of eco-fluvial dynamics. In this paper, the basic concept and main research content of eco-fluvial dynamics is introduced with the Yarlung Tsangpo River as the research example. This case study is an example of an aquatic ecosystem in an ever-changing environment because of the effects of climate change. The results of analysis of eco-fluvial dynamics will provide a scientific basis for decision support for the government.     

微曝气生态浮床净化入湖河口污染河水原位模型实验

针对污染河水黑臭缺氧、NH_4~+-N含量高等问题,研发了一种"漂浮载体悬挂弹性生物膜填料+水生植物并辅以人工微曝气系统"的微曝气生态浮床系统.通过原位模型实验,研究了其在大清河入湖河口对污染河水的净化效果,当水力负荷为1500mm/d时,对TN和NH_4~+-N的平均去除率分别为81.1%、91.3%,对TP的平均去除率为72.7%,对PO_4~(3-)-p的平均去除率为92.5%,对有机物亦有较强的去除能力;处理1m~3水需要的曝气费用约为0.007元.微曝气生态浮床系统整体运行稳定、去除效率高、能耗低,适合流水环境,可直接在污染河道和人湖河口区对污染河水进行自流净化.     

A field investigation of the sediment transport characteristics of a high sediment load intermittent river in Taiwan

Most rivers in Taiwan are intermittent rivers with relatively steep slopes and carry rapid sediment‐laden flows during typhoon or monsoon seasons. A series of field experiments was conducted to collect suspended load data at the Tzu‐Chiang Bridge hydrological station of the lower Cho‐Shui River, which is a major river with the highest sediment yield in Taiwan. The river reach was aggrading with a high aspect ratio during the 1980s. Because of sand mining and extreme floods, it was incised and has had a relatively narrow main channel in recent years. The experimental results indicated that typical sediment transport equations can correctly predict the bed material load for low or medium sediment transport rates (e.g. less than about 1000 tons/day‐m). However, these equations far underestimate the bed material load for high sediment transport rates. The effects of cross‐sectional geometry change (i.e. river incision) and earthquakes on the sediment load were investigated in this study. An empirical sediment transport equation with consideration of the aspect ratio was also derived using the field data collected before and after river incision. Copyright © 2012 John Wiley & Sons, Ltd.     

Long‐wave radiation and heat flux estimates within a small tributary in Catamaran Brook (New Brunswick,Canada)

River water temperature is an important water quality parameter that also influences most aquatic life. Physical processes influencing water temperature in rivers are highly complex. This is especially true for the estimation of river heat exchange processes that are highly dependent on good estimates of radiation fluxes. Furthermore, very few studies were found within the stream temperature dynamic literature where the different radiation components have been measured and compared at the stream level (at microclimate conditions). Therefore, this study presents results on hydrometeorological conditions for a small tributary within Catamaran Brook (part of the Miramichi River system, New Brunswick, Canada) with the following specific objectives: (1) to compare between stream microclimate and remote meteorological conditions, (2) to compare measured long‐wave radiation data with those calculated from an analytical model, and (3), to calculate the corresponding river heat fluxes. The most salient findings of this study are (1) solar radiation and wind speed are parameters that are highly site specific within the river environment and play an important role in the estimation of river heat fluxes; (2) the incoming, outgoing, and net long‐wave radiation within the stream environment (under the forest canopy) can be effectively calculated using empirical formula; (3) at the study site more than 80% of the incoming long‐wave radiation was coming from the forest; (4) total energy gains were dominated by solar radiation flux (for all the study periods) followed by the net long‐wave radiation (during some periods) whereas energy losses were coming from both the net long‐wave radiation and evaporation. Conductive heat fluxes have a minor contribution from the overall heat budget (<3·5%); (5) the reflected short‐wave radiation at the water surface was calculated on average as 3·2%, which is consistent with literature values. Results of this study contribute towards a better understanding of river heat fluxes and water temperature models as well as for more effective aquatic resources and fisheries management. Copyright © 2011 John Wiley & Sons, Ltd.     

Basic physicochemical characteristics of the state of Upper Amur surface water

The present-day ecological state of the Upper Amur is assessed. Specific features of water quality formation are demonstrated. Local sources of aquatic environment pollution are identified. The distributions of metals in dissolved and suspended forms in the river reach are examined.     

Pressure-specific and multiple pressure response of fish assemblages in European running waters

We classified homogenous river types across Europe and searched for fish metrics qualified to show responses to specific pressures (hydromorphological pressures or water quality pressures) vs. multiple pressures in these river types. We analysed fish taxa lists from 3105 sites in 16 ecoregions and 14 countries. Sites were pre-classified for 15 selected pressures to separate unimpacted from impacted sites. Hierarchical cluster analysis was used to split unimpacted sites into four homogenous river types based on species composition and geographical location. Classification trees were employed to predict associated river types for impacted sites with four environmental variables. We defined a set of 129 candidate fish metrics to select the best reacting metrics for each river type. The candidate metrics represented tolerances/intolerances of species associated with six metric types: habitat, migration, water quality sensitivity, reproduction, trophic level and biodiversity. The results showed that 17 uncorrelated metrics reacted to pressures in the four river types. Metrics responded specifically to water quality pressures and hydromorphological pressures in three river types and to multiple pressures in all river types. Four metrics associated with water quality sensitivity showed a significant reaction in up to three river types, whereas 13 metrics were specific to individual river types. Our results contribute to the better understanding of fish assemblage response to human pressures at a pan-European scale. The results are especially important for European river management and restoration, as it is necessary to uncover underlying processes and effects of human pressures on aquatic communities.     

The effect of varied dam release mechanisms and storage volume on downstream river thermal regimes

Temperature plays an essential role in the ecology and biology of aquatic ecosystems. The use of dams to store and subsequently re-regulate river flows can have a negative impact on the natural thermal regime of rivers, causing thermal pollution of downstream river ecosystems. Autonomous thermal loggers were used to measure temperature changes downstream of a large dam on the Macquarie River, in Australia’s Murray-Darling Basin to quantify the effect of release mechanisms and dam storage volume on the downstream thermal regime. The magnitude of thermal pollution in the downstream river was affected by different release mechanisms, including bottom-level outlet releases, a thermal curtain (which draws water from above the hypolimnion), and spill-way release. Dam storage volume was linked to the magnitude of thermal pollution downstream; high storage volumes were related to severe thermal suppressions, with an approximate 10 °C difference occurring when water originated from high and low storage volumes. Downstream temperatures were 8 ̶ 10 °C higher when surface releases were used via a thermal curtain and the spillway to mitigate cold water pollution that frequently occurs in the river. Demonstrating the effectiveness of engineering and operational strategies used to mitigate cold water pollution highlight their potential contribution to fish conservation, threatened species recovery and environmental remediation of aquatic ecosystems.