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An Application of a Computerized Mathematical Model for Estimating the Quantity and Quality of Nonpoint Sources of Pollution from Small Urban and Nonurban Watersheds.Ingraham, Charles John 01 January 1975 (has links) (PDF)
The problem of "Total Water Management" is reviewed; particular emphasis is given to the magnitude and intensity of pollution from nonpoint sources. The relationship between land usage in south Florida and subsequent effects upon receiving water bodies is discussed. Basic factors effecting hydrological and ecological subsystems are illustrated. The U.S. Army Corps of Engineers Urban Storm Water Runoff Mathematical Model, "STORM," is introduced. Model parameters and methodology are discussed. The mathematical relationships and modeling processes are reviewed and the model is exercised using a "new generation" southeast Florida community (The City of Palm Beach Gardens) as the subject of study. It is concluded that the model can be beneficial in supporting estimates of pollutant loading to receiving waters from nonpoint sources. Iteration with the model, varying control facility cost and capacity, provides a cost effective tool for land and water resource planners. However, due to the particular nature of soils, atmospheric and urban conditions in south Florida, the model should be calibrated with input constants and default values derived to more accurately reflect the southeast Florida environment.
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Ecotoxicological impacts of zebra mussels, Dreissena polymorpha, a new food source for lesser scaup, Aythia affinisTessier, Catherine. January 1996 (has links)
Zebra mussels (Dreissena polymorpha) have invaded a great proportion of the waters of the eastern part of North America. This mollusk may be a useful sentinel species for bioaccumulation of heavy metals and organic contaminants in aquatic ecosystems. The zebra mussel's capacity to bioaccumulate cadmium at environmentally relevant exposure and to sequester metals in metal-binding proteins, metallothioneins, was investigated. Elevated (relative to control) concentrations of Cd$ sp{2+}$ were detected in Dreissena exposed to $ ge$2 $ mu$g Cd/liter suggesting that zebra mussels cannot regulate Cd$ sp{2+}$ of trace exposure concentration. More than 85% of the measured Cd$ sp{2+}$ was bound to metallothioneins. / Lesser scaup (Aythya affinis) was assessed as a model species for potential impacts of zebra mussels on higher trophic levels. The feasibility of incubating and rearing scaup in semi-natural conditions was evaluated. A series of biomarkers was assessed in 3 groups of scaup fed a contaminant-free diet or diets containing zebra mussels from the St-Lawrence River or Lake Erie. / Lesser scaup proved to be a suitable species to raise in captivity providing daily water misting through out incubation and strict hygiene conditions during brooding. A hatching success of 89% was achieved. Appropriate housing, feeding and bathing conditions yielded low (3%) post-hatching mortality. / Phagocytosis and respiratory burst activities of heterophils of scaup were suppressed after 6 weeks of feeding on zebra mussels, compared to the control group. These two heterophilic functions were negatively correlated with the incidence of pododermatitis (bacterial feet infection), suggesting a suppression of the non specific immunity. Increased liver/body mass ratio and decreased hepatic vitamin A (retinol and retinyl palmitate) concentrations were observed in scaups fed zebra mussels. Lipid accumulation and glycogen overload were found in the livers of scaups fed mussels from the St-Lawrence River and the Lake Erie groups, respectively. These immunological, biochemical and histopathological biomarkers show promise for monitoring "early" injury and may help in the understanding of health impairment of different species of waterfowl exposed to xenobiotics via contaminated food sources.
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Ecotoxicological impacts of zebra mussels, Dreissena polymorpha, a new food source for lesser scaup, Aythia affinisTessier, Catherine. January 1996 (has links)
No description available.
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Determination of Bioconcentration Potential of Selected Pharmaceuticals in Fathead Minnow, Pimephales promelas, and Channel Catfish, Ictalurus punctatusNallani, Gopinath C. 12 1900 (has links)
The primary objective of this work was to determine the tissue-specific bioconcentration factors (BCFs) of the selected pharmaceuticals: norethindrone (NET), ibuprofen (IBU), verapamil (VER), clozapine (CLZ) and fenofibrate (FFB) in two freshwater fishes: fathead minnow and channel catfish. BCF tests on fathead followed the standard OECD 42-day test while a 14-day abridged test design was used in catfish exposures. Additional objectives included a) comparing the measured BCFs to the US EPA's BCFWIN model predicted values, b) comparing the BCF results from the standard and reduced tests, and c) prediction of chronic risk of the pharmaceuticals in fish using the human therapeutic plasma concentrations. Each test included uptake and depuration phases to measure tissue-specific kinetic BCFs. The results indicated that all the pharmaceuticals, except IBU, have the potential for accumulation in fish. Estimated BCFs for NET, VER and FFB may not be significant in view of the current regulatory trigger level (BCF ≥ 2000); however, CLZ's BCF in the liver had approached the criterion level. Significant differences were noticed in the tissue-specific uptake levels of the pharmaceuticals with the following general trend: (liver/kidney) > (gill/brain) > (heart/muscle) > plasma. IBU uptake was highest in the plasma. When compared to the measured BCFs, predicted values for NET, IBU, VER and FFB were slightly overestimated but did not differ largely. However, the measured BCF of CLZ in the liver was approximately two-orders of magnitude higher than the predicted level. The tissue-BCFs for the two species were not widely different indicating the potential usefulness of the reduced BCF test. Comparison of fish and human plasma levels indicated that NET, CLZ and VER have the potential to cause chronic effects in fish.
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Assessment of the impact of water and sediment quality on aquatic macroinvertebrate assemblages in the Blyde River of the Olifants River System, Limpopo ProvinceMalakane, Karabo Concelia January 2019 (has links)
Thesis (M.Sc. (Zoology) -- University of Limpopo, 2019 / The Olifants River is one of the major river systems in South Africa, providing water for industries, mines, agricultural and domestic activities. Consequently, the river has turned out to be one of the most polluted rivers in South Africa. The Blyde River is an important tributary of the Olifants River, known for its continuous flow and good water quality. However, the recent increase in human activities such as, commercial agricultural and large-scale forestry practices in the catchment may have a negative impact on the quality of the water, which may consequently affect the aquatic biota community structure. The aim of the study was to assess the water and sediment quality of the Blyde River using aquatic macroinvertebrates as bioindicators and the South African Scoring System version 5 (SASS5) protocol was followed.
Seven sampling sites were selected at Blyde River and five samples were collected per site. Collected macroinvertebrates were identified to family level and classified according to their tolerance levels to pollution at the University of Limpopo Biodiversity Laboratory. In addition, seasonal readings of the physico-chemical parameters such as, pH, dissolved oxygen (DO), temperature, salinity, total dissolved solutes (TDS) and electrical conductivity (EC) were recorded in situ using YSI Model 554 Datalogger with a 4 m multiprobe and a Mettler Toledo SevenGo™. Most of the physico-chemical parameters recorded at Blyde River were within the South African water quality guidelines for aquatic ecosystems.
Metals such as, As, Al, Ba, B, Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni, Se, Ag, Sr, Sn, Ti, V, and Zn were tested from the water column, sediments and macroinvertebrate tissue. Almost all the metals analysed from the water column and sediments were within the quality guidelines. Out of the twenty tested metals, As, Ag, Cu, and Zn exceeded the recommended quality guidelines in the water column at some sites. Only As, Cr and Cu exceeded the recommended quality guidelines in the sediments.
The most abundant macroinvertebrates were from the orders Ephemeroptera, Diptera, and Trichoptera at all sites. There was a similar macroinvertebrate community structure across the sites, supported by the positive correlation analysis among the sites (r > 0.4). Wildlife Estate and Wildrivers Estate had the highest and lowest numbers of sensitive macroinvertebrates respectively. The highest percentage of
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sensitive macroinvertebrate taxa was recorded in winter and the highest percentage of tolerant species was recorded in summer. This was also supported by the SASS indices, the SASS score, number of taxa and average score per taxon (ASPT) were highest in winter, followed by autumn, spring and lowest in summer. The overall SASS indices showed that the water quality condition at most of the sites at Blyde River could be considered as good. All the seven sites on average fell under ecological band A and B, except for the Wildrivers Estate, thus, the water quality status of the river could be described as unmodified and largely natural with few modifications. / VLIR
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The development of water pollution law in late nineteenth century America, 1870-1905Peterson, James Scott January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Toxic effects of freshwater pollutants on the survival, behaviour and reproduction of Gammarus pulex (L.) and Asellus aquaticus (L.)Poulton, Madeline June January 1990 (has links)
The toxic effects of cadmium on aspects of the survival, behaviour and reproduction of Gammarus pulex and Asellus aquaticus are described in some detail. Some of the laboratory procedures were validated in field experiments. The presence of the parasites Pomphorhynchus laevis and Echinorhynchu_s1truttae does not modify the toxicity of cadmium (0.01-1.0 mgl ) to their intermediate-Fost G. pu7ex. Pretreatment for 24 hours with 0-47 μgl cadmium alters the distribution of separation times when precopula pairs of G. pu7ex are disrupted by the invertebrate anaesthetic 2- phenoxyethanol. Precop1la is directly disrupted by exposure to cadmium (0.1-12.7 mgl )_ýut recovery can follow. Pretreatment with cadmium (3-140 μgl ) for 24 hours, of similarly sizeci male G. pulex and subsequent exposure to 0.13 and 2.23 μgl while in competition for access to a female may increase tolerance and enhance reproductive success, or initiate irreversible toxic effects and impair competitive ability. Exposure of female G. pulex-1to 2.0 and 9.6 μg1 , and female A. aquaticus to 40.2 pgl cadmium pre-fertilization reduces their fecundity. Brood development times of G. pulex and A. aquaticus exposed to 2.1 and 12.4 μg1-1 cadmium postfertilization are extended by 2 and 2.7 days respectively. The embryonic development and abortion during brooding are described in detail for A. aquaticus. An explanation of reduced final brood size in Asel7us is Postulated. Growth of juveniles of both test species exposed during brooding is assessed. Single and repeated 24 hour field simulations of acidic deposition demonstrate increased host sensitivity of G. pulex infected with P. 7aevis. The effects of low pH and elevated aluminium concentrations are mitigated to some extent by liming. Six hour field simulations of the individual components of farm waste demonstrated that infected gammarids were more susceptible under conditions of low dissolved oxygen than uninfected conspecifics.
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The sewage treatment capability of non-backwash biological aerated filter systems for small communitiesHodkinson, Brenden James January 1997 (has links)
Biological Aerated Filters (BAFs) are wastewater treatment systems which contain support media for biofilm development and provide oxygen at the base of the reactor to sustain aerobic microbial treatment processes. The aims of this study were to characterise and quantify the treatment capability of non-backwash BAFs used in small sewage treatment works, and therefore establish design recommendations. Three full scale trial BAFs, a field operational small sewage treatment plant, and a full scale aeration testing facility were studied. The trial BAFs, with simulated secondary settlement, provided carbonaceous stabilisation under various hydraulic loadings and airflow rates. Nitrification showed no relationship with airflow rate, but was inhibited at high hydraulic loadings. Sludge production in the BAFs was less at higher airflow rates, due to improved stabilisation of organic solids. Media specific surface area had little effect on treatment performance. Downflow operation generally provided better treatment than upflow operation, with high levels of suspended solids stabilisation, considered a function of longer residence times. The mean BAF residence times determined empirically were considerably shorter than the design residence times, and may have inhibited treatment potential. The oxygen transfer efficiency (OTE) of coarse bubble diffusers was enhanced in a simulated BAF, due to the effects of the support media. Fine bubble diffuser OTE was inhibited by the media. Coarse diffusers may be more appropriate than fine diffusers for small non-backwash BAFs, a function of performance and cost efficiency. A small packaged sewage treatment plant incorporating BAFs produced a well nitrified effluent with reasonable organic stabilisation, and showed little diurnal or seasonal variation in effluent quality. The plant compared well to other small sewage treatment systems, providing treatment in a small footprint. Design recommendations for non-backwash BAFs and small sewage treatment plants incorporating BAFs have been established, based on the knowledge gained during this study. It has been demonstrated that non-backwash BAFs are appropriate for use in small sewage treatment works.
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Agricultural sources for lake pollution : soil erosion in Slapton Ley catchmentPuvaneswaran, Pathmadevy January 1990 (has links)
The purpose of this study was to investigate the role of soil erosion as a factor in lake pollution and in particular the transport of phosphorus from field soils to streams and lakes in association with mobile sediment. Four land uses were selected as representative of the Slapton Ley catchment area to investigate the levels of phosphorus in the soil. The surface soil samples from the selected land use areas were analysed to determine the water-soluble phosphorus level in solution and exchangeable phosphorus level in sediment. Twelve experimental plots were studied in order to assess the erosional effects of overland flow and thus to determine the level of phosphorus from different land uses which may be influencing the eutrophication of the lake. It was concluded that slope angle, vegetation cover, surficial soil properties, animal influence and agricultural practice are the main factors influencing sediment transportation by overland flow. Estimated results for the agricultural fields indicated that the actual phosphorus loss to the Ley is always greater in sediment than solution and actual phosphorus loss in sediment is greater in arable (root) and cereal than in grass. The point water samples (136) from 13 different sources were grouped. Mean value of phosphorus concentration from the point sources indicated that the agricultural land uses such as arable and cereal provide 2 times more exchangeable phosphorus attached to sediment than the other land uses whereas farm and sewage provided 5 times more soluble phosphorus in water than other sources. Phosphorus concentration during peak discharge was examined for the Cara catchment. The results indicated that the ratio of phosphorus concentration in suspended sediment to phosphorus concentration in water is 240: 0.3 and that there is a linear relationship between phosphorus in water and phosphorus in sediment during the peak discharge. Sediment phosphorus levels in the marsh area were also examined. The results indicated that the top layers of the marsh sediment particularly at the surface, have higher phosphorus concentration than the lower layers and that there are higher levels in sediment than in water. From these results the conclusion was drawn that the soluble phosphorus in water is at highest concentration in sewage works effluent. However this effluent contributes a small proportion of phosphorus load to the Ley compared with the arable (root), cereal and grass lands in the catchment. Agricultural sources, particularly arable sources such as root and cereal play an important role on soil erosion as a factor in lake pollution and in particular in the transport of phosphorus from field soils to streams and lakes in association with mobile sediment in the Slapton Ley catchment.
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The use of a biomarker to assess the effect of xenobiotic exposure on the freshwater invertebrate Gammarus pulexWarwick, Oliver William Tindle January 1997 (has links)
Contamination of freshwaters is of concern because of its effect on ecosystem health. The effect of contamination can be assessed at all levels of biological organisation, from the ecosystem level to the molecular level. At the biochemical level, enzymes that are involved in the detoxification of organic chemical contaminants are useful as markers of contaminant exposure as they are often one of the first systems to respond to chemical exposure. Furthermore, changes in the activity of these enzymes may be indicative of effects at higher levels of biological organisation. In this study, the use of the detoxification enzyme glutathione stransferase (E. C. 2.5.1.18) (GST) in the freshwater invertebrate Gammarus pulex (Crustacea: Amphipoda), as a biomarker of organic xenobiotic exposure and effects was assessed. Toxicant induced changes in GST activity were related to changes in energy status and physiological energetics. A GST assay was developed that allowed the rapid analysis of GST activity in up to ninety individual animal samples simultaneously. Optimum sample handling and assay conditions were determined for the assay of GST in G. pulex, and extrinsic factors (e. g. environmental temperature, feeding and holding conditions) and intrinsic factors (e. g. body size), affecting variability of GST activity in G. pulex were assessed The effect of exposure to the organic xenobiotics lindane( an organochlorinein insecticide) and alcohol ethoxylate( a non-ionic surfactand detergent)on GST activity in G.pulex was described. The magnitude and duration of the response of GST activity to exposure to both chemicals was assessed under laboratory conditions and with alcohol ethoxylateu, sing outdoor artificial streams. The use of GST as a marker of pesticide exposure in field populations of G. pulex that were subject to pesticide contamination was studied in comparison with animals from non-contaminated, reference sites. The differences in GST activity between animals from a contaminated site and clean site were investigated by short-term and long-term exposure to lindane in the laboratory. Changes in energy status and physiological energetics were investigated in G. pulex on exposure to lindane by measuring glycogen concentration and scope for growth. Measuring these parameters on short-term and long-term exposure to lindane allowed the sensitivity of these responses to be related to the GST response and allowed the energetic cost of exposure to be assessed. It was concluded that increase in GST activity may providea rapid and sensitive biomarker of xenobiotic exposure in the short-term and in populations subject to pesticide contamination. The affect on GST activity may be indicative of effects at higher levels of biological organisations, such as scope for growth and glycogen concentration However, GST activity is affected by a variety of intrinsic and extrinsic factors and should therefore be used only asp art of a comparative study. Because of the transient nature of the GST response in situ assessments should be based on 24-hour exposure periods.
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