bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sustainable Management of Urban Lakes: A New Environmental Challenge
Authors: Barica J. 
Published: March 2019

Abstract
In view of the exponential growth of human population in urban areas during the last century, more attention should be paid to large city ecosystems as specific ecological bioregions. There is a need to shift the present biocentric-naturalist views prevailing in environmental circles to include the human population as an integral part of the ecosystem in a stringent application of the principles of the ecosystem approach and sustainable development. A new environmental realism is needed: boundaries and limits of ecological sustainability have to be respected and necessary caps imposed through rational urban planning and settlement policies. The urban lakes can serve as living indicators of good environmental management or mismanagement, as well as overall urban environmental health.
Evidence of Recent Eutrophication of an Urban Lake in Nanjing, China
Authors: Dickman M. D. 
Published: March 2019

Abstract
There is very little known about urban lakes in China, and for this reason this paper provides a synthesis of palaeolimnological and past and present phytoplankton studies of Xuanwu Lake, an urban lake near the center of Nanjing, in Jiangsu Province, China.
Documented changes in biotic species diversity and water chemistry in this urban lake over the last thirty years have been attributed to progressive eutrophication associated with lake in-filling, commercial harvesting of plants and fish and intense industrial and urban activities within the lake's watershed. During the last decade, phytoplankton biomass in Xuanwu Lake has increased ten fold. This has resulted in a steady shallowing of the lake's photic zone to a depth of less than 0.7 m with Secchi transparencies of 0.3 to 0.4 m.
Wind-generated currents prevent anoxia from occurring in this shallow wind-swept lake no matter how eutrophic the lake. As a result, many of the negative impacts of hypertrophication, such as anoxia, fish kills and noxious odors, are avoided. Thus, shallow lakes like Xuanwu Lake can become eutrophic without producing long periods of hypolimnetic anoxia such as those frequently reported for deeper eutrophic lakes. It was concluded that it is important to treat deep urban lakes differently from shallow urban lakes as the latter systems rarely display extended periods of anoxia, fish kills and noxious odors.
Artificial Marshes to Maintain Water Quality: The Beach of Ile Notre-Dame, Montréal
Authors: Vincent Gilles 
Published: March 2019

Abstract
In June 1990, the City of Montréal opened a beach on an artificial lake in the southern sector of Ile Notre-Dame in the Saint Lawrence River, a man-made island built for Expo ’67. This lake is fed from the Saint Lawrence River and the beach stretches some 600m with a swimming area of approximately 15 000 m2. Since the desired environmental character was that of a natural lake, it was decided to avoid the use of conventional methods of water purification such as treatment with chlorine. Instead, a series of techniques more compatible with natural systems were chosen in order to maintain water quality. The major component of these techniques is a “filter-lake” complex. Occupying an area of 20 000 m2, the “filter-lake” complex consists of four ponds of varying depth where more than 100 000 aquatic plants of different native species were introduced. Intake pipes draw 28 litres/second of water into the first pond and then, water circulates by gravity through the three remaining ponds. During the last two seasons, several parameters were monitored in order to evaluate the efficiency of the system. The parameters considered were: soluble reactive phosphorous, total phosphorus, dissolved phosphorus, nitrates, ammonium, suspended solids and faecal coliforms. Preliminary results indicate that the system of artificial wetlands used at the beach of Ile Notre-Dame is efficient in water purification. The ponds are very good traps for soluble reactive phosphorus and nitrates. A good interception is also observed in the second pond for total phosphorus and suspended solids. Faecal coliforms removal however seems uncertain and long-term effectiveness is questionnable.
Management Strategies for Eutrophication and Macrophyte Growth in Two Urban Lakes in Saint-Bruno, Quebec
Authors: Leduc Roland , Anderson M. Robin 
Published: March 2019

Abstract
Two small, shallow lakes (Ruisseau and Village lakes), located in Saint-Bruno near Montreal (Québec), were studied in 1987 to determine the extent of, and to propose alleviation solutions to eutrophication and to macrophyte growth. Flows and various water quality parameters were monitored in the influents and in the lakes, and macrophytes were harvested at four different locations in Village Lake. Both lakes were found to be highly eutrophic. The dominant plant specie was found to be Myriophyllum spicatum. Biomass densities were high with values of 206, 212 and 395 g/m2 at three of these sampling locations. A number of alternatives which could mitigate eutrophication and the presence of macrophytes are discussed in terms of technical feasibility and cost. Source control of nutrients, along with citizens involvement, and partial control of macrophytes were recommended management strategies.
Reproductive Dysfunction and MFO Activity in Three Species of Fish Exposed to Bleached Kraft Mill Effluent at Jackfish Bay, Lake Superior
Authors: Munkittrick K.R. , Van Der Kraak G.J. , McMaster M.E. , Portt C.B. 
Published: March 2019

Abstract
Our recent studies have demonstrated reproductive dysfunction in white sucker (Catostomus commersoni), longnose sucker (C. catostomus) and lake whitefish (Coregonus clupeaformis) populations exposed to bleached kraft mill effluent (BKME). Although all three species show elevated levels of hepatic mixed function oxygenase (MFO) activity and depressed circulating steroid levels, we have been unable to provide clear evidence of whether these two events are directly linked to whole organism changes. Although depressed steroid levels appear to be linked to delayed sexual maturity, changes in fecundity and reduced secondary sexual characteristics in white sucker and lake whitefish, longnose sucker show no impacts of reduced steroid levels on reproductive performance. Installation of secondary treatment at this pulp mill did not alleviate the steroidal dysfunction or MFO induction. However, samples collected after a two week maintenance shutdown showed a return to reference levels of MFO activity in both sexes and of steroid levels in male fish. The relationship between elevated MFO activity and depressed steroid levels is unclear, but detailed experiments suggest that the two phenomena are not directly linked. White sucker show depressed steroid production and impaired reproductive regulation independent of MFO activity.
Chlorate Discharges from Pulp Mills: An Examination of Effects on River Algal Communities
Authors: Perrin C. J. , Bothwell M. L. 
Published: March 2019

Abstract
To avoid the formation of organochlorine compounds in pulp products and effluents discharged into the environment, there is a trend in the North American pulping industry to change from molecular chlorine to chlorine dioxide bleaching. However, chlorate (ClO3−) formed during chlorine dioxide bleaching is known to have toxic effects in some marine algae and has been implicated in environmental problems in the Baltic Sea. This study examined the potential effects of chlorate on natural freshwater, riverine diatom communities characteristic of many rivers in western Canada. Under low ambient river nitrate concentrations (ca. 10 µg•L−1 NO3−N), chlorate additions of up to 500 µg•L1 ClO3 did not reduce the specific growth rates (µ) or change the taxonomic composition of the attached riverine diatom community. The lack of chlorate toxicity to freshwater diatoms suggests that the nitrate uptake and/or reduction mechanism(s) of freshwater diatoms have much higher affinities for NO3 than ClO3 compared to many marine macroalgae. These results indicate that chlorate discharged from new or upgraded pulpmills into freshwater river environments will not cause environmental changes to the dominant algal producers such as diatoms.
Modelling the Fate of Organochlorine Chemicals in Pulp Mill Effluents
Authors: Mackay Donald , Southwood Jeannette M. 
Published: March 2019

Abstract
A comprehensive and flexible water quality model is described which can be used to evaluate the fate of chemicals discharged from an industrial source, such as a pulp mill, into a multi-compartment receiving environment consisting of three water columns exposed to the atmosphere, each with a sediment compartment, and five classes of organisms exposed to chemicals present in water and sediment. The aim of the model is to provide a method by which known loadings of organochlorines and other chemicals from a specific mill can be used, along with other input information (e.g., inputs from other mills, advective inflow from nearby waters, and from atmospheric deposition) to deduce amounts and concentrations of chemicals and process rates (e.g., rates of evaporation or transformation) in water, sediments and biota.
Results are presented for an evaluative system and for a trichlorophenol and a trichloroguaiacol in a real system in Northern Ontario. Discrepancies found between observed and calculated concentrations of the trichlorophenol and the trichloroguaiacol in the receiving environment are discussed. Recommendations are made for studies which will elucidate the causes.
Inability of Resin Acid Exposure to Elevate EROD Activity in Rainbow Trout (Oncorhynchus mykiss)
Authors: Ferguson M.L. , Servos M.R. , Munkittrick K.R. , Parrott J. 
Published: March 2019

Abstract
The induction of mixed function oxygenase enzymes, including ethoxyresorufin-o-deethylase (EROD), has been reported in fish downstream of bleached kraft mills in both Scandinavia and Canada. The compound(s) responsible have not been identified. Several experiments were conducted to determine if resin acids can induce EROD activity in rainbow trout (Oncorhynchus mykiss). Interperitoneal injections (i.p.) of dehydroabietic and abietic acid (50 mg/kg) did not elevate EROD activity after 2, 4 or 10 days. Dehydroabietic acid i.p. at 500 mg/kg did not increase EROD activity after 4 days. A mixture of ten resin acids i.p. at 370 mg/kg or water borne exposure at 100 µg/L did not induce EROD after 4, 8, or 16 days. Rosin gum i.p. at 370 mg/kg also did not induce EROD. These results suggest that resin acids are not the compounds primarily responsible for EROD induction below bleached kraft pulp mills.
A Batch Study of the Aerobic and Anaerobic Removal of Chlorinated Organic Compounds in an Aerated Lagoon
Authors: Chernysh Alexandra , Liss Steven N. , Allen D. Grant 
Published: March 2019

Abstract
In order to further our understanding of the removal of adsorbable organic halogen (AOX) from bleached kraft pulp mill effluent in an operating lagoon, controlled batch studies (at 22°C and 30°C) were conducted under aerobic and anaerobic conditions. The removal of AOX ranged from 17 to 70% and the presence of sludge significantly increased the removal of both AOX and total organic carbon (TOC). There was no further significant removal of AOX beyond two days for the aerobic experiments and beyond 10 days for the anaerobic experiments. The removal of AOX under anaerobic conditions was not significantly different from those under aerobic conditions and increasing the temperature caused a significant increase in the removal of AOX. There was no significant difference in the overall removal or patterns of removal between AOX and TOC. A mass balance showed that the sludge represented the major fraction of organically bound chlorine in the mixed liquor.
Broad Spectrum Analysis of Alcohols as Indicator Compounds for Phathalate Plasticizer Contamination in Water and Soil
Authors: Headley John V. , Krause Darwin , Swyngedouw Chris 
Published: March 2019

Abstract
The effectiveness of present approaches to the study of the fate and transport of phthalate esters and adipates in surface water and ground water samples is limited by ubiquitous levels of background contamination in the field and the laboratory. An alternative approach is described in which C7-C11 alcohols are used as indicator compounds to circumvent the problems associated with contamination arising from plasticizers at an industrial site. The approach combines information obtained from GC/MS analyses of selected samples with information from a cost-effective pre-screening GC/FID technique. The approach (a) provides broad spectrum data for trend analysis, (b) minimizes the occurrence of false positives, and (c) reduces the cost of analyses required for the delineation of contaminated plumes. For contaminated samples, the concentration of phthalate esters was approximately 3-4 times higher than detectable levels of alcohols. Although the detection limits are 0.1 mg/L and 1 μg/g for water and soil samples, respectively, there is a threshold concentration of phthalate esters of approximately 300 μg/g, below which alcohols were not observed.
A Management Strategy for Contaminated Sediment: Assessment and Remediation
Authors: Zarull M.A. , Reynoldson T.B. 
Published: March 2019

Abstract
Sediment contaminated with metals, persistent toxic organics and nutrients represents a significant concern throughout the Great Lakes. The highest levels of sediment-associated contaminants and some of the worst manifestations of their resultant problems are found in the urban-industrial harbours, embayments and river mouths. These “Areas of Concern” require complete problem definition and remediation of all impaired uses. However, our ability to fully remediate contaminated sediments in these nearshore areas is limited by the availability of proven technology, adequate assessment data and suitable restoration goals.
All of these requirements are currently in the research, development and demonstration phases. Each of these is discussed in the context of their technical problems and further research needs and development directions are indicated.
Bioenergetic Simulations of Mercury Uptake and Retention in Walleye (Stizostedion vitreum) and Yellow Perch (Perca flavescens)
Authors: Harris R.C. , Snodgrass W.J. 
Published: March 2019

Abstract
Bioenergetic models for mercury accumulation in walleye (Stizostedion vitreum) and yellow perch (Perca flavescens) were calibrated on the basis of data which indicate that methylmercury concentrations in oxic, unpolluted lake waters are on the order of 0.04 to 0.40 ug m−3. This range reflects improved analytical capabilities in recent years and is significantly lower than earlier estimates on the order of 4 μg m−3. For both yellow perch and walleye, the calibrations of bioenergetics equations in this study strongly suggest that the food uptake pathway is dominant for methylmercury in oxic unpolluted freshwaters, in comparison to uptake across the gills. The food pathway is predicted to be responsible for 90% or more of methylmercury uptake in yellow perch and walleye in oxic freshwaters with methylmercury concentrations less than 0.3 to 0.4 μg m−3. As a result of the dominance of the food uptake pathway, mercury concentrations in fish were strongly influenced by the mercury concentration in the diet. A change in the source of the walleye diet from benthos to fish resulted in a significant increase in the rate of mercury accumulation. The calibrations resulted in a 5-year old yellow perch achieving a mercury concentration of 0.15–0.20 μg g−1, and a 4-year old, 1 kg walleye achieving a mercury concentration of about 0.45 μg g−1.
Bioconcentration of Cadmium in Aquatic Invertebrates: Geochemical, Physiological and Behavioural Influences
Authors: Evans R. Douglas , Lasenby David C. 
Published: March 2019

Abstract
The geochemical control of cadmium (Cd) availability to invertebrates in lake water is examined. In particular, the influence of lake water acidity on the bioconcentration factors (BCF’s) for Cd in various organisms is investigated. The relationship between BCF and pH is inverse for some organisms and not significantly different than zero for others. This is taken as evidence that factors other than geochemistry influence metal concentrations in organisms. Specific examples of the importance of physiological and behavioural processes are given. The hypothesis that the differences in the relationship between BCF and pH for different organisms is related to surface adsorption of metal is discussed.
Increase in Metallothionein in Freshwater Mussels Anodonta grandis grandis Exposed to Cadmium in the Laboratory and the Field
Authors: Malley D.F. , Klaverkamp J.F. , Chang P.S.S. 
Published: March 2019

Abstract
Freshwater unionid mussels, Anodonta grandis grandis, were exposed in the laboratory to nominal [Cd] of 0, 5, 10, 20 and 50 ug/L to determine: 1) whether this species produces metallothionein (MT) in response to Cd exposure, 2) which body parts are involved in the production, and 3) the dose-response relationship between (MT] in body parts and the treatment [Cd] in the laboratory compared with that in a field population exposed to Cd.
Background [MT], as µg MT/g wet weight, measured in mussels freshly collected from a pristine lake were: kidney, 38.9 &gt; visceral mass, 15.0; foot, 13.7; gill, 12.5 &gt; mantle, 3.4. After these mussels were exposed to Cd in the laboratory for 22 days, blood [Cd] in the 5–50 µg/L Cd exposures averaged 5.1, 7.1, 9.3 and 15.8 times, respectively, the blood [Cd] in the 0 µg/L treatment. After the 22-day exposure, only [MT] in gill showed a statistically significant relationship with treatment [Cd] indicating that MT was induced in response to Cd exposure. The [MT] in gill after 22 days exposure to 50 µg/L Cd was 24.2 µg/g, 72% higher than in mussels exposed for this period to 0 µg/L Cd.
In comparison, [MT] in the gill of mussels collected from a whole lake receiving experimental additions of Cd over three ice-free seasons (epilimnetic means of 0.08, 0.05 and 0.1 µg/L Cd, respectively), was 36.5 ug/g after two seasons exposure and 35.0 µg/g after three seasons, indicating a many-fold greater response to water-borne Cd in the field compared with the laboratory. The other body parts in the mussels collected after three seasons in the Cd-treated lake also contained significantly greater [MT] (kidney, 118.3 µg MT/g; visceral mass, 36.3; foot, 26.0 and mantle, 9.5) than did those from the pristine lake. The field samples thus indicate that all these body parts produce MT in response to exposure to Cd.
WQTA — A Water Quality Trend Analysis Program
Authors: Tsanis I.K. 
Published: March 2019

Abstract
A series of programs have been developed using the statistical package Minitab to evaluate trends of water quality parameters over a time period. These programs are included in an interactive program with graphic capabilities called Water Quality Trend Analysis (WQTA). The output files from the retrieval and year programs of the National Water Quality Data Bank (NAQUADAT) are used as input files to the program. The graphic output is obtained using the graphical package Axum. Twelve-month moving averages and the Spearman’s rank correlation are applied for trend assessments. The components of variability (seasonal, trend and random) of the water quality parameters are modelled using linear regression. The methods are applied successfully to selected physical and chemical water quality parameters collected at the mouth of Niagara River, at Niagara-on-the-Lake, during the period 1976–89. The specific conductance was decreasing for the period as the discharge was increasing, due to higher dilution effects. A modest downward trend for total phosphorus was observed for the period 1976–84, and there is no trend between 1984-89. A strong decreasing trend for chloride was observed during the 1977–84 period but this has levelled off since then. A strong upward trend for iron and a weak downward trend for lead was evident over the study period.
A Probabilistic Model for the Determination of Acid Rain Levels
Authors: Provost Serge B. , Barnwal Rajesh K. 
Published: March 2019

Abstract
This article gives, in closed form, exact representations of the probability content of elliptical cylinders lying in three-dimensional Gaussian fields. The concentration of a pollutant present in the air, in a given neighborhood, is assumed to follow a trivariate normal distribution. Noting that the amount of a certain pollutant absorbed by a cluster of clouds—whose volume is approximated by an ellipsoid—is proportional to the pollutant’s integrated concentration distribution over the elliptical cylinder that the cluster sweeps out, and that the trajectories of the rain drops coming from this cluster also fill an elliptical cylinder, one could, for example, use the derived results to determine the amount of sulphuric acid deposited on a given area of the earth’s surface during rainfall.
Recycling Human Waste: Composting Toilets as a Remedial Action Plan Option for Hamilton Harbour
Authors: Wynia Wendy , Sudar Anne , Jones Gary 
Published: March 2019

Abstract
Hamilton Harbour has been designated as an Area of Concern in Ontario by the International Joint Commission due to water quality and ecosystem quality problems. One option that has been suggested as a means of reducing sewage loadings to local sewage treatment plants is the composting toilet. To investigate this option, background research was conducted regarding the design and functioning of the composting toilet over the years. It was found that composting toilets break down organic material through an aerobic microbial process with the end products being largely carbon dioxide, water and a humus-like material that can be used as a soil conditioner.
Identified composting toilet owners (14 in total), mainly cottagers, were contacted and surveyed regarding their experience and degree of satisfaction with this type of toilet. Various related problems and benefits were identified. A random sample survey was then mailed out to 1200 Hamilton/Burlington residents to gauge the social acceptability of the composting toilet option in an urban setting. Responses tended to be quite positive and concern for environmental problems, specifically water quality, was apparent. Results indicated that nearly a quarter of the homeowners in the Hamilton/Burlington area would consider installing a composting toilet in their homes.