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Aquatic Ecological Classification and Evaluation of Streams and Stream Reaches in the Upper Roanoke River Basin, Virginia
Description:
The purpose of this study is to "establish a data base and methodology for classifying...the streams of the Roanoke Basin into a hierarchy of ecological systems" and to "establish evaluative criteria and methodology for classifying and ranking streams within the ecological systems relative to their state of environmental quality" (p. R1).
Date:
March 30, 1979
Creator:
North Texas State University. Institute of Applied Sciences.
Item Type:
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Partner:
UNT Institute of Applied Sciences
The Determination of Uptake and Depuration Rate Kinetics and Bioconcentration Factor of Naphthalene and Lindane in Bluegill Sunfish, Lepomis macrochirus
Description:
Bluegill were exposed to 3 and 30 pg/L lindane and 20 and 200 pg/L naphthalene to determine uptake rate constants, K1 depuration rate constants, K2, and bioconcentration factors, BCF. Correlations were determined between lipid normalized and non-lipid normalized BCFs, and between observed Kl, K2 and BCFs and predicted values. The K1 values for both chemicals and concentrations were similar. The K2 values were different (1.04 day~1, 0.46 day 1). Naphthalene was more rapid. BCFs for lindane (315)…
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Date:
August 1981
Creator:
DeFoer, Marguerite J.
Partner:
UNT Libraries
Determination of Biotransformation and Biodegradation Rate Constants for Naphthalene, Lindane and Phenol
Description:
Biotransformation and biodegradation rate constants were determined for naphthalene, lindane, and phenol in water samples from three different sources. Rate constants produced from monitoring disappearance of the parent chemical (biotransformation) were compared to those obtained from mineralization of the chemical (ultimate biodegradation) by ¹⁴CO₂ evolution as well as acidification of the residual ¹⁴C-labeled compound (primary biodegradation). Rate constants were statistically different for t…
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Date:
December 1981
Creator:
Crawford, Judith Chase
Partner:
UNT Libraries
Microbiological Studies of Biological Activated Carbon Filters Used in Water Treatment
Description:
A collaborative pilot study of the microflora on biological activated charcoal (BAC) filters employed in the tertiary treatment of drinking water revealed the principle bacterial genera to be Pseudomonas, Alcaligenes, Achromobacter, Bacillus, Micrococcus, Corynebacterium, Chromobacterium, Microcyclus and Paracoccus. The microbial population of the filters paralleled seasonal carbon dioxide production. Of particular interest were the effects of the BAC miroorganisms upon precursors of trihalomet…
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Date:
December 1981
Creator:
Chang, Eichin
Partner:
UNT Libraries
Lethal and Sublethal Effects of Hemoxidants, Particularly Nitrite, on Selected Aquatic Animals
Description:
A research program was developed to investigate basic and applied aspects of toxicity, both lethal and sublethal, of hemoxidants, particularly nitrite, on fish, non-fish aquatic vertebrates, and crayfish. The major objectives of this research were to determine A) acute and sublethal toxicity of nitrite to selected aquatic organisms: 1. aquatic salamander larvae, Ambystoma texanum, 2. swamp crayfish, Procambarus simulans, 3. bluegill, Lepomis macrochirus, 4. bullfrog, tadpoles, Rana catesbiana, …
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Date:
May 1982
Creator:
Huey, David W. (David Worley)
Partner:
UNT Libraries
The Influence of Stream Regulation on Genic Differentiation and Thermal Tolerance in the Red Shiner, Notropis Lutrensis
Description:
Genetic variation and thermal tolerance were surveyed for variation attributed to nonuniform selection pressures for five populations of the red shiner, Notropis lutrensis, collected from regulated and unregulated portions of a Texas river. Populations within 30 km of a hypolimnion-release dam that experience large thermal perturbations were found to have higher levels of heterozygosity, higher levels of polymorphism, significantly depressed levels of upper thermal tolerance endpoints, and grea…
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Date:
December 1982
Creator:
King, Timothy L. (Timothy Lee)
Partner:
UNT Libraries
Comparative Feeding Ecology of Leaf Pack-Inhabiting Systellognathan Stoneflies (Plecoptera) in the Upper Little Missouri River, Arkansas
Description:
The feeding ecologies of leaf pack-associated systellognathan stoneflies were examined from 6 June 1980 21 May 1981. Species composition, seasonal abundance, nymphal growth, feeding habits and mouthpart morphology were determined for the eight dominant stonefly species. Prey preferences and predator-prey size relationships were also examined for omnivorous and carnivorous species. Foregut analysis from 2860 individuals indicated opportunistic feeding on the most abundant prey insects, usually i…
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Date:
August 1983
Creator:
Feminella, Jack W. (Jack William)
Partner:
UNT Libraries
Plasma Ion Concentrations in Selected Fishes from Four North Central Texas Reservoirs with Different Salinities
Description:
Mean salinity concentrations in the four reservoirs (Moss, Ray Hubbard, Texoma and Possum Kingdom) ranged from 0.2 ppt in Moss Lake to 2.01 ppt in Possum Kingdom Lake. Reservoir sodium and chloride concentrations were hypotonic to hypertonic to plasma levels in all species. Interspecific differences were seen in ionic concentrations within each reservoir. Total osmotic and sodium concentrations in carp, Cyprinus carpio, were correlated to their concentrations in the reservoirs. No such relation…
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Date:
December 1983
Creator:
Del Regno, Kenneth J. (Kenneth Joseph)
Partner:
UNT Libraries
Testing and Evaluation of Environmental Fate Models Using Aquatic Microcosms and Three Organic Chemicals
Description:
Two compartment (sediment and water) flow-through model ecosystems were constructed to investigate the compartmentalization of different organic chemicals. Lindane, naphthalene, and mirex were pumped into the systems and resultant compartmental chemical concentrations determined. Steady state concentrations were compared to those predicted by two environmental fate models - EXAMS (Exposure Analysis Modeling System) and SLSA (Simplified Lake and Stream Analysis) which were developed by EPA-Athen…
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Date:
December 1983
Creator:
Staples, Charles A. (Charles Allen)
Partner:
UNT Libraries
Biology and Production of Net-Spinning Caddisflies (Hydropsychidae And Philopotamidae) in a Regulated Portion Of The Brazos River, Texas
Description:
Four species of net-spinning caddisflies, Hydropsyche simulans Ross, Cheumatopsyche lasia Ross, Cheumatopsyche campyla Ross and Chimarra obscura (Walker) are common in the regulated portions of the Brazos River. Hydropsyche simulans spun capture nets with the largest meshdimensions; the two Cheumatopsyche species' nets had the next largest meshes, and Chimarra obscura spun nets with the smallest dimensions. Cheumatopsyche lasia and C. campyla constructed nets with similar sized meshes. The numb…
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Date:
May 1984
Creator:
Malas, Diane M. (Diane Mary)
Partner:
UNT Libraries
The Effects of Pulp and Paper Mill Wastewaters on Phytoplankton Primary Productivity in the Red River, Louisiana
Description:
Responses of phytoplankton productivity in the Red River to unbleached pulp and paper mill wastewaters were monitored using in situ ^14C incubation. Preoperational studies, conducted prior to the discharge of mill wastewaters varied seasonally, but revealed similar productivity trends when compared with postoperational studies, conducted after mill discharges began entering the Red River. Carbon assimilation rates measured downstream of mill discharge were generally greater than upstream levels…
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Date:
May 1984
Creator:
Holler, Jeffrey Dee
Partner:
UNT Libraries
Qualitative and Microcosm Predictions of Effects of Endothal for Control of Myriophyllum spicatum in Pat Mayse Lake, Texas
Description:
Qualitative and microcosm models were used to predict effects of herbicide application for control of Myriophyllum spicatum. Predictions were compared to data from Pat Mayse Lake, a Texas reservoir, where localized areas were treated with endothall. Although milf oil was temporarily eliminated, when endothall was used according to manufacturer's directions, no ecologically significant direct or indirect effects were observed on nontarget species or abiotic water quality. Comparisons of the pred…
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Date:
May 1984
Creator:
Hinman, Mark L.
Partner:
UNT Libraries
Effects of Suspended Solids on Bioavailability of Chemicals to Daphnia magna and Pimephales promelas
Description:
Three suspended solids types containing a range of physicochemical characteristics were used to determine the effect of suspended solids on the bioavailability of acenaphthene, 1,2,4,5-tetrachlorobenzene, zinc, and chlordane to Daphnia magna and Pimephales promelas. Generally, the bioavailability of zinc and chlordane decreased due to interactions with all suspended solids types while bioavailability of acenaphthene and 1,2,4,5-tetrachlorobenzene were not clearly reduced. Partition coefficients…
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Date:
December 1984
Creator:
Hall, W. Scott (Warren Scott)
Partner:
UNT Libraries
Fate of Endothall in Aquatic Environments
Description:
Hazard assessment of pesticides in aquatic environments requires accurate predictions of persistence and compartmentalization. A strategy for developing confidence in predictive fate models, such as the Exposure Analysis Modeling System (EXAMS) and the Simplified Lake and Stream Analysis model (SLSA), is to test the models using carefully chosen chemicals in semi-controlled and field situations. An objective of this approach would be to isolate the variability in a particular fate process and t…
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Date:
December 1984
Creator:
Reinert, Kevin H. (Kevin Howard)
Partner:
UNT Libraries
Food Habits, Dietary Overlap and Electivity of Non-Game Insectivorous Fishes in an Ozark Foothills Stream
Description:
Etheostoma spectabile, E. punctulatum, and Cottus carolinae were sampled Mar., 1983, - Feb., 1984, in Flint Creek, Oklahoma. Immature E. spectabile ate primarily microcrustaceans, while mature fishes relied more on mayflies and amphipods. Juvenile E. punctulatum fed upon mayflies, amphipods, and Asellus. Mature E. punctulatum ate primarily mayflies, and other relatively larger prey. Cottus carolinae consumed chironomids almost exclusively in Jan. - Feb., 1984, while mayflies were predominant th…
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Date:
May 1985
Creator:
Todd, C. Stan (Charles Stan)
Partner:
UNT Libraries
Aquatic Heterotrophic Bacteria Active in the Biotransformation of Anthracene and Pentachlorophenol
Description:
Dominant genera of bacteria were isolated from three river waters during anthracene and pentachlorophenol biotransformation studies. The genera Pseudomonas, Acinetobacter, Micrococcus, Chromobacterium, Alcaligenes, Azomonos, Bacillus, and Flavobacterium were capable of biotransforming one or both of these compounds. These isolates were subjected to further biotransformation tests, including river water and a basal salt medium with and without additional glucose. The results of these experiments…
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Date:
August 1985
Creator:
Entezami, Azam A. (Azam Alsadat)
Partner:
UNT Libraries
Degradation of Humic Substances by Aquatic Bacteria
Description:
A variety of aquatic bacteria were isolated and tested for their ability to degrade humic substances and their aromatic residues/monomers which serve as precursors of the trihalomethanes (THMs) found in chlorinated drinking waters. The majority of them were Gram-negative, oxidative types dominated by pseudomonads. Most of the 146 isolates were found to utilize as their sole source of carbon several or more of ten aromatic compounds known to be products of degradation of humus and also to be pre…
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Date:
August 1985
Creator:
Baiu, Saleh Hamed Salem
Partner:
UNT Libraries
Effects of Water Source, Suspended Solids, and Acclimation on Biotransformation of 2 /4-Dichlorophenoxy Acetic Acid in Aquatic Systems
Description:
In recent years there has been a great deal of scientific interest in processes that affect the fate of organic chemicals in the environment. one main reason for this increased interest is due to greater environmental concern over accidental or purposeful release of these chemicals into the environment by man. A major environmental concern is the increased use of pesticides over the last few years. In the thirty years prior to 1978 the use of pesticides has increased by a factor of forty (Ridge…
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Date:
August 1985
Creator:
Moses, Christopher K. (Christopher Karam)
Partner:
UNT Libraries
Aquatic Vegetation Nutrient Budgets and Sedimentation in a Southwestern Reservoir
Description:
During four growing seasons, aquatic vascular plant production and distribution were studied in Pat Mayse Lake, Texas, a 2425 hectare oligo-mesotrophic reservoir. The dominant macrophyte population was Myriophyllum spicatum L. Growth rates and regrowth rates of mechanically harvested Myriophyllum beds were found to be dissimilar. Based on estimates of watermilfoil nutrient content, there were insufficient nutrients in the entire population to alter the trophic status of this reservoir should al…
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Date:
May 1986
Creator:
Clifford, Philip A. (Philip Alan)
Partner:
UNT Libraries
New Descriptions, Intraspecific Variation and Systematic Importance of Drumming Behavior in Selected North American Plecoptera
Description:
Drumming behavior is described for the first time in 33 North American Plecoptera species, and signals of an additional five species, Pteronarcys pictetii, Acroneuria abnormis, Paragnetina media, Clioperla clio and Isogenoides zionensis, are further detailed. An out-group comparison of behavioral characters in all 104 world species whose drumming is known showed that the behavior is more advanced in the Arctoperlaria Group Systellognatha than in the Group Euholognatha. In general, tapping, mono…
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Date:
December 1986
Creator:
Maketon, Monchan
Partner:
UNT Libraries
Eutrophication Potential of Reclaimed Wastewater: An Ecological Study of Water Reuse in an Urban Texas Reservoir
Description:
This study determined effects of addition of secondarily treated municipal wastewater effluent on an urban reservoir receiving system. Monthly water quality monitoring of the receiving reservoir and the wastewater, chemical analysis, and monthly laboratory algal assays, were conducted from September 1984 to September 1985. The nutrient status and algal growth potential of the receiving water and the wastewater confirmed the biostimulatory properties of the wastewater. Field validation studies w…
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Date:
May 1987
Creator:
Dodson, Susan Boyd
Partner:
UNT Libraries
An Evaluation of the Short-Term Embryo-Larval and Seven-Day Larval Test Methods for Estimating Chronic Toxicity of Zinc to the Fathead Minnow (Pimephales promelas)
Description:
Chronic toxicity of zinc to Pimephales promelas was estimated by conducting replicate static and static-renewal short-term embryo-larval tests and static-renewal seven-day larval tests. The two test methods were highly reproducible. Daily renewal of test solutions had little effect on the toxicity of zinc, however, the stage of development at which exposure was initiated affected the sensitivity of the toxic endpoints measured. The most sensitive and reproducible endpoint in the embryo-larval t…
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Date:
May 1987
Creator:
Stewart, Susan Michels
Partner:
UNT Libraries
Predicting the Site-Specific Bioavailability of Zinc Using the Indicator Species Procedure: A Case Study
Description:
National Water Quality Criteria intended to protect aquatic life and their uses from the adverse effects of pollutants may not be appropriate due to site-specific factors that alter chemical bioavailability. The Indicator Species Procedure may be used to derive site-specific criteria in order to account for differences in site-specific bioavailability. This procedure was implemented using zinc for three chemically different site (river) waters. The purpose of this study was to quantify the bioa…
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Date:
May 1987
Creator:
Parkerton, Thomas F.
Partner:
UNT Libraries
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