bluuebunny/crossref_metadata_2025_split huggingface dataset:
Réponse de la flore bactérienne de l'estuaire du Saint-Laurent à un éventuel déversement de pétrole
Authors: Siron R. , Pelletier E. , Delille D. , Brochu C. 
Published: March 2019

Résumé
Un groupe de cinq mésocosmes de 3,5 m3 chacun, permettant de travailler en eaux froides, a été utilisé pour étudier l’évolution de la flore bactérienne de l’estuaire du Saint-Laurent sous différentes conditions de contamination (pétrole dispersé chimiquement, non traité ou relargué à partir d’un substrat) et à différentes saisons (températures de l’eau de mer variant de −1,8 à 16°C). Des concentrations en pétrole de &lt;1 à plus de 67 mg.L−1 ont été testées. La dispersion chimique du pétrole induit une augmentation de la croissance des bactéries hétérotrophes viables (BHV). Le temps de génération diminue lorsque la température de l’eau augmente et la densité bactérienne maximale atteinte en mésocosmes augmente généralement avec la quantité de pétrole dispersé dans la colonne d’eau. La croissance des BHV est également stimulée par les produits pétroliers relargués à partir d’un substrat contaminé. Lorsque le pétrole est déversé en surface et non traité, la faible concentration dans la colonne d’eau ne permet pas une augmentation significative de la microflore hétérotrophe. La présence de pétrole induit toujours une augmentation de la densité des bactéries dégradant le pétrole (BDP). En conditions glaciales extrêmes (température moyenne de −1,6°C; couche de glace en surface), l’activité hétérotrophe était accrue par la présence de pétrole dispersé, alors que dans le même temps, la microflore totale restait relativement constante. Une diminution de la diversité spécifique de la communauté bactérienne était notée après deux semaines d’exposition à une concentration maximale de 4,6 mg.L−1 en pétrole dispersé. La communauté bactérienne indigène qui a été échantillonnée dans des conditions hivernales peut être considérée comme “psychrophile tolérante” ou “psychrotrophe”. Les analyses chromatographiques en phase gazeuse effectuées sur le pétrole résiduel ont mis en évidence une biodégradation significative des hydrocarbures aliphatiques et aromatiques, qui est révélée ici par la diminution des rapports n-alcanes/isoprénoides et 2-méthylnaphtalène/ 1-mèthylnaphtalène. Le taux de biodégradation augmente avec la quantité de pétrole dispersé dans la colonne d’eau et avec la température de l’eau. En conditions hivernales extrêmes, la biodégradation restait très limitée durant les deux semaines suivant la contamination.
Water at the Outlet of the St. Lawrence River Part II - Suspended Matter and Solid Loadings from 1989 to 1991
Authors: Barbeau C. , Sérodes J.-B. , Côté J.-E. 
Published: March 2019

Abstract
During two years (1989–91), water samples of the St. Lawrence River were taken on a daily basis at the intake of the drinking water treatment plant of Lévis, in front of Québec City, and analyzed for suspended matter. Data indicate that the physical behaviour of the particulate phase is identical to that observed for the dissolved phase (see paper I) and, in contrast to the steady concentrations at the exit of Lake Ontario, the suspended matter at the outlet of the St. Lawrence River varies on a monthly and seasonal basis. The concentration varies from a mean value of 8 mg/L in winter to 30 mg/L in spring, 10 to 15 mg/L in summer, and 14 to 19 mg/L during fall, with an annual mean of 17 mg/L. The maxima occur in spring and are higher than 100 mg/L (108–179). High concentrations of solids are observed at dates of high flow, except in November, when a heavy solid discharge is noted independently of water flow. Tributaries on the south shore contribute little to the flow of water but they carry half of the suspended matter at Levis during periods of low concentration of solids and more than the two-thirds during periods of high concentration.
The calculated sediment load of the St. Lawrence River at Lévis for 1990 is 7 million tons and the annual load based on the 1989–91 period is 6.6 million tons. More than 95% of the solids come from downstream of Lake Ontario. Seasonally, 50% of the annual load occurs during spring, 10% in winter, while fall and summer contributes each 20%.
Flux of PCBs into Water in Little Lake, Peterborough, Ontario
Authors: Metcalfe C.D. , Ferguson M.L. , Metcalfe T.L. 
Published: March 2019

Abstract
The Otonabee River downstream of Peterborough, Ontario, has been contaminated with PCBs as a result of a history of industrial discharges into Little Lake. It has been suggested that downstream sites have become contaminated as a result of desorption of PCBs from contaminated Little Lake sediments, In a laboratory microcosm study, the PCB flux from Little Lake sediments into water was calculated to be 0.4 µg/m2/d, which, when extrapolated to the sediment area of Little Lake, corresponds to a total PCB flux of 0.09 g/d. However, from analysis of water samples upstream and downstream of Little Lake, the total flux of PCBs from Little Lake was calculated to be 13.2 g/d. This discrepancy between calculated flux rates indicates that either the laboratory microcosm study underestimated PCB flux, or there is another source of PCBs in Little Lake other than contaminated sediments. The preponderance of highly chlorinated PCB congeners in water samples collected downstream of Little Lake lends support to the latter hypothesis.
An Overview of Constructed Wetlands as Alternatives to Conventional Waste Treatment Systems
Authors: Hamilton Hugh , Nix Peter G. , Sobolewski André 
Published: March 2019

Abstract
Constructed wetlands are an attractive alternative to conventional wastewater treatment under certain conditions. This review presents background information on wetland treatment and wetland design, and outlines the potential for wetlands to treat water contaminated with organic compounds including hydrocarbons. The major mechanisms that reduce contaminant concentrations in wetlands are sedimentation, filtration, chemical precipitation, microbial interaction and plant uptake. The presence of bacteria in “biofilms” on the enormous plant and detrital surface area in wetlands is fundamental to their ability to degrade complex organic contaminants. There are few examples in the literature of wetlands being used to control organic chemical pollution. However, the very high level of biochemical activity in the water column and upper sediment layer in wetlands, combined with a high degree of ecological resilience, suggests that wetlands can be an attractive low cost, low energy, low maintenance alternative to conventional treatment methods.
Anaerobic-Aerobic Lagoon Treatment of Kraft Mill Effluent for Enhanced Removal of AOX
Authors: Lee E.G.-H. , Crowe M.F. , Stutz H. 
Published: March 2019

Abstract
A continuous-flow sequential anaerobic-aerobic lagoon treatment process was developed and evaluated for removal of adsorbable organic halide (AOX) from whole-mill kraft effluent at both laboratory and pilot-scale. The rationale underlying the development of the process was that the AOX removal efficiency of aerated lagoons currently in use might be significantly increased through relatively simple modification.
Bench-scale studies showed that sequential anaerobic-aerobic treatment of whole-mill kraft effluent resulted in AOX-removal efficiencies of over 70% at hydraulic retention times (HRTs) of 10 days, 5 days and 2 days. In contrast, only 20%, 35% and 36% removal was obtained in a control aerobic lagoon. Pilot-scale studies showed that up to 65% removal of AOX from whole-mill kraft effluent was consistently obtained at HRTs ranging from 5 to 10 days. This compares with typical AOX removal efficiencies in conventional aerated lagoons of about 25%. Conversion of the anaerobic section in the pilot-scale lagoon from a simple sludge blanket to a combination of sludge blanket and submerged biofilm further increased AOX removal efficiencies to about 70%.
Bench-Scale Testing of Activated Sludge Treatment for a TMP Wastewater
Authors: Liver Susan F. , Miyamoto Henry K. , Black Steve A. 
Published: March 2019

Abstract
A continuous bench-scale treatability study determined the most desirable design and operating parameters for waste treament of effluent from an integrated Canadian TMP newsprint operation. An initial batch study indicated that the effluent was biologically treatable and provided initial biological kinetic (biokinetic) parameters for this wastewater. This information was used to design the continuous study.
Conventional activated sludge treatment of the mill wastewater can produce an effluent which meets the federal regulations for BOD5, suspended solids, and toxicity to D. magna. Predictions using cumulative toxicity units (CTU) indicate that the treated effluent would also be non-toxic to O. mykiss as well. Analyses of ammonia in the treated effluent indicated that un-ionized ammonia concentrations would be non-toxic to rainbow trout.
Mass balances incorporating the results of the bench-scale studies and the effect of fibre carry-over from the primary clarifier, defined the full-scale operating conditions selected as: an F/M of 0.35 d−1, HRT of 0.5 days, SRT of 6 days and an MLSS of 4400 mg/L (when no polymer is used at the primary clarifier). These conditions were arrived at by selecting the smallest HRT which still corresponded to an MLSS &lt; 5000 mg/L, an F/M &lt; 0.4 d−1 and an SRT &gt; 5 days.
Based on the kinetics for biological treatment of mill effluent, at the maximum mill production, adequate BOD5 removal will still easily be obtained under the above operating conditions, even during cold weather periods.
Operational concerns identified by bench-scale testing indicated that a full-scale facility should incorporate an anoxic selector (although the anoxic selector did not show measurable improvement in the bench-scale tests) and micronutrient addition for filamentous bulking control.
An Alternative Approach for Computation of Annual Toxic Contaminant Loadings in Urban Runoff
Authors: Xu P. , Marsalek J. , Tsanis I.K. 
Published: March 2019

Abstract
An alternative approach was presented for estimating annual toxic contaminant loadings in urban runoff. In this method, the mean contaminant concentrations are calculated by a regression method. In the computation of contaminant loadings, the load component transported by the liquid phase was estimated by multiplying the mean concentration in water by the runoff volume simulated by the STORM model. The load component transported by suspended solids was calculated by multiplying the mean concentration in solids by the event mean solids concentrations reported in the NURP Program. The loadings calculated by this method were compared with those obtained from whole water samples, and the differences are within an order of magnitude. Since more parameters are used in this approach, it appears more suitable for use in sensitivity analysis of parameters, and more flexible in evaluations of controls measures.
Characterization of the Chemical Constituents and Toxicity to Aquatic Organisms of a Municipal Landfill Leachate
Authors: Ernst W.R. , Hennigar P. , Doe K. , Wade S. , Julien G. 
Published: March 2019

Abstract
Samples of leachate were obtained at four locations in effluent streams from a municipal waste landfill near Halifax, Nova Scotia. Samples were analyzed for a number of physical and chemical parameters using standard laboratory procedures. Samples were also screened to identify organic chemicals by matching mass spectrometer output against a reference spectrum library. Static acute toxicity tests (48 h to 96 h) were also conducted on samples using rainbow trout (Oncorhynchus mykiss), brook trout (Salvelinus fontinalis) and water fleas (Daphnia magna) as test organisms. The acute toxicity of leachate was primarily due to its ammonia content; however, the chronic effects on aquatic organisms of the range of organic chemicals identified in these samples remains undetermined. Paradoxically, the leachate discharge to the receiving water body reduced the toxic potential of that water to the organisms tested.
Modelling Sedimentation and Resuspension in Lakes
Authors: Podsetchine V. , Huttula T. 
Published: March 2019

Abstract
A 2-D vertical flow and suspended matter transport model and a 3-D transport model are described. Existing parameterizations of resuspension and deposition of sediments on the bottom are discussed. Models were applied for calculation of unsteady sediment transport in Lake Karhijärvi, Finland, for a five-day period with high winds and heavy rain in autumn 1992. A parabolic distribution of vertical eddy diffusivity was found to be applicable. Erosion was approximated with cubic dependence on bed shear stress. The 3-D model showed that the observed turbidity peak in the middle of the lake was caused by suspended matter transport through the River Susikoski. Sediment resuspension was found to be limited in the areas with depth less than 1 m. The 2-D vertical model was useful for determination of erosion under certain weather conditions, but for detailed analysis in space and time a 3-D model with high resolution is required.
Hydrodynamic and Ecological Models for the Gulf of Finland
Authors: Tamsalu Rein , Myberg Kai , Sarkkula Juha 
Published: March 2019

Abstract
Measurement programs and model simulations of hydrodynamics and ecology of the Gulf of Finland, a sub-basin of the Baltic Sea, have been carried out from the 1970s. The measurements indicate that there exists a wind-independent background current in the gulf. A 2.5-D baroclinic, prognostic, hydrodynamic model has been developed. The vertical structure of temperature and salinity is based on a self-similarity structure of the sea. The model results showed that the background current in the measurements can be explained by the important role of buoyancy-driven circulation in the studied area. There are quasi-stationary fronts of salinity and velocity in the gulf. The maintenance of these fronts is based on the opposing effects of river water discharge and salty water input from the main Baltic Sea. These processes are modified by the baroclinic circulation and bottom topography. A box model for calculation of ecosystem characteristics was developed for the Gulf of Finland. The plankton organisms are divided into size classes. The aquatic ecosystem characteristics were calculated by using the results of the hydrodynamic model (flow velocity, temperature, salinity, density, sea level and turbulent fluxes) as input data. The verification of the model was carried out against the Baltic Monitoring Program (BMP) data. Long-term water quality simulations were done by changing external nutrient load.
Hydrodynamics of Lakes Ladoga and Onega
Authors: Beletsky D.V. , Filatov N.N. , Ibraev R.A. 
Published: March 2019

Abstract
Results of physical experiments and modelling in lakes Ladoga and Onega during the last two decades are presented. Synoptic ship surveys were conducted during the period of thermal bar formation and during full stratification while currents and temperature were recorded using a network of buoys. The primary emphasis is given to the temporal and spatial variability of currents and temperature fields, numerical modelling and model verification. The data obtained and model calculations reveal the fundamental role of wind-induced upwellings, coastal jets, thermal fronts and mesoscale eddies in lake hydrodynamics.
Application of Remote Sensing in the Visible Spectrum for Hydrodynamic Studies in Lakes
Authors: Kondratyev K. Ya. , Pozdnyakov D.V. 
Published: March 2019

Abstract
Large scale limnological applications of active optical remote sensing techniques are described. An airborne Nd:YAG laser with frequency doubling and tripling facilities is used. Algorithms for inferring concentrations in phytoplankton chlorophyll (CHL) and dissolved organic matter (DOM) are developed for inland water bodies. Through the analysis of specific features of retrieved 2-D fields of CHL and DOM, it is possible to characterize the surficial manifestations of various fundamental thermohydrodynamic phenomena in lakes and water storage reservoirs, such as upwellings, cores, stream patterns, etc.
Thermal Processes in Lake Onega
Authors: Boyarinov P.M. , Palshin N.I. , Petrov M.P. 
Published: March 2019

Abstract
Results from many years of experimental research on the thermal regime of Lake Onega are reported. The discussion includes a description of heat transport processes, free convection, thermal bar development, progression, and upwelling. Also discussed is the equation of state regarding ion composition of fresh water and its implication to thermodynamic processes such as thermohaline convection and microstructure inversions.
Evaluation of Phosphorus Removal in the Activated Sludge Process
Authors: Duffy S.J. , Deutschman J.E. , vanLoon G.W. 
Published: March 2019

Abstract
The chemical behaviour of aluminum and phosphorus is examined at various stages in an activated sludge wastewater treatment facility which uses alum as a coagulant. It is found that most of the phosphorus leaving the plant is in the form of unsettled particulates associated with residual aluminum. This result is in agreement with numerous other studies and has led us to postulate that by optimizing conditions under which coagulants are added to the wastewater stream, improved settling of the resulting flocculant material would occur and this would be indicated by lower total phosphorus and turbidity. The hypothesis was tested on batch samples in the laboratory and at the plant, and also using a bench-scale continuous model plant. The data indicate that addition of alum using moderate mixing after the effluent leaves the aerator could result in a final effluent with significantly lower turbidity and phosphorus.
Fish as Indicators of Ecological Sustainability: Historical Sequences in Toronto Area Streams
Authors: Wichert Gordon A. 
Published: March 2019

Abstract
A weighted species association tolerance index with respect to water quality (WSATI-WQ) was crafted based on the literature on the sensitivity of different species to certain types of changes in their habitats. This index was used to compare changes through time in ecological conditions at locales in 12 subwatersheds in Toronto streams. As expected, WSATI-WQ scores were generally largest at relatively undisturbed sites and became progressively smaller with increasing deviation from an undisturbed state. Benefits from improved management of sewage have offset some of the degradation associated with earlier urbanization. It appears that modern urban stresses are less harmful to aquatic systems than were urban stresses of the past since some tolerant fish species presently live in urban streams where fish were absent 40 years ago.
Quality Assurance for Environmental Monitoring
Authors: Lawrence John , Aspila Keijo I. 
Published: March 2019

Abstract
A data quality management framework for ecological monitoring programs is described. A total quality management framework has three key elements: quality management planning, quality control, and quality assessment and audit. The quality management plan establishes the data quality objectives, the protocols and procedure documents to be followed, reporting schedules, training needs and the individuals to be held accountable. Quality control is the systematic set of procedures carried out by each operational unit involved in the measurement process. Quality assessment is the set of procedures designed to provide the overall check on data quality while verifying that the other components of the framework are adequate.
Mobilization of Mercury from Estuarine Suspended Particulate Matter: A Case Study in the Yalujiang Estuary, Northeast China
Authors: Jingsheng Chen , Fei Tang , Feiyue Wang 
Published: March 2019

Abstract
Trace metal concentrations in suspended particulate matter in estuaries are dependent on the extent of mixing between river and seawater. Superimposed on this physical mixing, chemical mobilization from the particulates may take place. This paper presents the behavior of mercury in the Yalujiang estuary, northeast China. It deals with (i) field observations on the variations of mercury concentrations in the estuarine suspended material and (ii) the experimental mobilization of mercury from contaminated estuarine sediment by exposure to artificial seawater.
Three stations on two cross sections in the upper and lower Yalujiang estuary were sampled over at least two or three complete tidal cycles. The field observations show that there is a clear mobilization of mercury from the suspended material during the maximum mixing of river and seawater. The experimental mobilization suggests that mobilization of mercury from the suspended particulates in seawater is caused not only by complexing with CI’ and ion-exchanging with the alkali and alkaline earth cations in seawater, but also by the dissolution of humic substances in the particles by seawater and the release of associated mercury.
Occurrence of Butyltin Compounds in Tianjin and Dalian Harbours, China
Authors: Shugui Dai , Guolan Huang , Yong Cai 
Published: March 2019

Abstract
Subsurface seawater samples from 12 locations in Tianjin and Dalian harbours were analyzed for butyltin species by gas chromatography-atomic absorption spectrophotometry, and the presence of butyltin species was reported for the first time in these two harbours. Butyltin species were determined in most sampling locations. The concentrations of butyltin species in Tianjin Harbour were higher than those in Dalian Harbour. Some water samples in Tianjin Harbour contained the highly toxic tributyltin at concentrations which could cause growth retardation on chronic exposure to a sensitive organism (rainbow trout yolk sac fry). The concentrations of butyltin species were higher in areas of heavy boating and shipping traffic. This is consistent with butyltin use as an antifouling agent in some paints for boats, ships and docks.
Water Quality Modelling for an Estuary in Johore
Authors: Koh Hock-Lye , Lim Poh-Eng , Lee Hooi-Ling 
Published: March 2019

Abstract
A tidal tributary of the Johore River with a palm oil mill located upstream was selected for this study. Hydrographic and hydrological data were collected to study the hydraulic regimes in the tributary due to freshwater flows and tidal forces subject to various meteorological conditions. A simple tidal model was built to represent the hydraulic flows. Water quality parameters including BOD5, DO, pH, ammonia nitrogen, suspended solids and temperature were determined during three tidal phases, namely high water, intermediate water and low water, to assess the existing water quality of the river. The impacts of the discharge of palm oil mill effluent and other likely discharges on the water quality of the river were assessed by means of a computer model, modified from the WASP4 model developed by the U.S. EPA, for contaminant fate and transport in surface water.
The Use of Biological and Chemical Parameters to Determine the Toxicity and Bioaccumulation of Wastewaters
Authors: Zhang Linlin , Sun Xiaoran 
Published: March 2019

Abstract
This study was conducted to determine the different parameters of the wastewater entering the Haihe River in the city of Tianjin. Different biological and experimental testing methods were used, including bioluminescence, the Ceriodaphnia dubia test, simulated bioaccumulation by thin-layer chromatography, and GC-MS analysis. Two samples showed acute toxicity to bioluminescent bacteria and Ceriodaphnia dubia, and contained many kinds of chemical compounds which tended to bioaccumulate. The wastewaters were also assessed and a basis for the river pollution control was provided.