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  Partner: UNT Libraries
 Degree Discipline: Biology
 Collection: UNT Theses and Dissertations
Toxicity Studies of Aquatic Actinomycetes

Toxicity Studies of Aquatic Actinomycetes

Date: August 1952
Creator: Fair, Helena Juengermann
Description: Since Actinomycetes have been isolated from finished public drinking water, it is believed that the organisms are unaffected by the chlorination and flocculation of water treatment plants and pass as spores through the filters into the general distribution system. For this reason it was deemed imperative to study the toxic effects of these organisms.
Contributing Partner: UNT Libraries
Some Physiological Effects of Chlorine upon Two Chlorine Resistant Algae

Some Physiological Effects of Chlorine upon Two Chlorine Resistant Algae

Date: June 1966
Creator: Beddow, David G.
Description: This research is concerned specifically with the growth of two selected algae found surviving in chlorinated water in outdoor swimming pools. Unialgal cultures were used to determine the free chlorine residuals that these algae were able to tolerate.
Contributing Partner: UNT Libraries
Observations on the Life History of the Brown Spider, Loxosceles Reclusa Gertsch and Muliak

Observations on the Life History of the Brown Spider, Loxosceles Reclusa Gertsch and Muliak

Date: August 1967
Creator: Horner, Norman
Description: This research was undertaken primarily to further elucidate the life history of this medically important spider. Special attention was given to rearing experimental spiders under as near-natural environmental conditions as possible.
Contributing Partner: UNT Libraries
Investigating Realistic Scenarios of Biodiversity Loss on Ecosystem Functioning: Extirpation of Rare Species and Food Web Collapse in Tropical Floodplain Lagoons

Investigating Realistic Scenarios of Biodiversity Loss on Ecosystem Functioning: Extirpation of Rare Species and Food Web Collapse in Tropical Floodplain Lagoons

Date: May 2012
Creator: Pendleton, Richard McCall
Description: This thesis investigates the influence of nonrandom species loss on the structure and functioning of trophic floodplain lagoons. Two experiments were conducted based on different realistic scenarios of biodiversity loss using multitrophic fish assemblages derived from long-term survey data. Loss of fish diversity influenced overall ecosystem multifunctionality of these lagoons through complex multitrophic interactions throughout the aquatic food web. These results indicate that biodiversity loss from diverse multitrophic ecosystems can influence ecosystem structure and function and likely deviate from simplified food chain dynamics or patterns that emerged from single trophic level studies.
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Spatial and Temporal Influences of Water Quality on Zooplankton in Lake Texoma

Spatial and Temporal Influences of Water Quality on Zooplankton in Lake Texoma

Date: May 2000
Creator: Franks, Jessica L.
Description: Seventy-one aquatic species including the copepodids and nauplii were identified from Lake Texoma from August 1996 to September 1997. Zooplankton community structure, abundance and spatial and temporal distributions were compared among five lake zones delineated a priori based on chloride concentration. The zones, in order of decreasing chloride concentration, are the Red River zone (RRZ), Red river Transition zone (RRTZ), Main Lake zone (MLZ), Washita River Transition zone (WRTZ) and Washita River zone (WRZ). Bray Curtis Similarity Index showed community structure was most similar in the two Red River arm zones, the two Washita River arm zones and the MLZ. Zooplankton abundance was greatest in the Red River arm (312 org/L), intermediate in the Washita River arm (217 org/L) and least in the Main Lake body (103 org/L). A significant increase in the abundance of a deformed rotifer, Keratella cochlearis, was observed mainly in the Red River arm during a second study from March 1999 to June 1999. Seasonal dynamics, rather than spatial dynamics, were more important in structuring the zooplankton community, especially in the two river arms. Spatial variance was solely attributed to station and zone effects independent of time for a few crustacean species and many of the ...
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Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation

Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation

Date: May 2012
Creator: Sloop, Jordan
Description: While there is growing evidence that shade/flood tolerance tradeoffs may be important in distributions of bottomland hardwood trees and indications that they should apply to herbs, no studies have definitively explored this possibility. Four years of field data following historic flooding were supplemented with a greenhouse experiment designed to identify interactions congruent with tradeoffs. Fifteen bottomland species were grown in two levels of water availability and three levels of shade over 10 weeks. Results indicate responses of Fimbristylis vahlii and Ammannia robusta are consistent with tradeoffs. Modification of classical allometric responses to shade by substrate saturation indicates a potential mechanism for the tradeoff in A. robusta. Responses indicating potential for increased susceptibility to physical flooding disturbance are also discussed.
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Capillary Permeability to Narrow-Range Macromolecular Dextrans at Normal and Hypobaric Pressures

Capillary Permeability to Narrow-Range Macromolecular Dextrans at Normal and Hypobaric Pressures

Date: December 1972
Creator: Norris, John Anthony
Description: In view of its varied concepts and interpretations, and because of the discrepancies produced by the previous utilization of polydispersed dextrans, a study using extremely narrow-range molecular weight dextran fractions was initiated to reevaluate and consolidate some of the aspects of capillary permeability. A portion of the study was performed under decreased barometric pressure in order to clarify further some of the mechanisms involved in particulate transfer across the capillary endothelial membranes. Gel filtration procedures augmented the study as an assessment of the polydispersity effects of the dextrans employed.
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Actinoplanes Philippinensis: Effect of Carbon Sources on Zoospore Production

Actinoplanes Philippinensis: Effect of Carbon Sources on Zoospore Production

Date: May 1968
Creator: White, Olivia
Description: Actinomycetes are able to utilize a great variety of carbohydrates, like sugar. The particular kind of sugar and its concentration has decisive effect on the growth of microorganisms. The proper nutritional media aids also in the production of spores. Based on this generalization, that the growth and sporulation of microorganisms are greatly influenced by the nature and the concentration of carbohydrates, an attempt has been made to study Actinoplanes philippinensis with respect to this influence.
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Studies of Selected Cyanophyte Response to Varying Geosmin Concentrations

Studies of Selected Cyanophyte Response to Varying Geosmin Concentrations

Date: May 1973
Creator: Richey, Harvey M., III
Description: The purpose of this investigation is to determine the effect of varying geosmin concentrations on the growth of selected cyanophytes which did not produce a notable odor in culture.
Contributing Partner: UNT Libraries
Distribution, Size, Condition, and Food Habits of Selected Fishes in a Reservoir Receiving Heated Effluent from a Power Plant

Distribution, Size, Condition, and Food Habits of Selected Fishes in a Reservoir Receiving Heated Effluent from a Power Plant

Date: December 1972
Creator: McNeely, David L.
Description: This study was undertaken in order to provide further insight into the effects of artificial heating on the fisheries of a small reservoir in the Southwest. The following specific objectives were established: (1) to map the reservoir for the distribution of heated water, (2) to determine the distribution of selected species of sports, rough, and forage fish in areas affected by the effluent and in areas not affected, (3) to compare size and condition of selected species of fish from areas affected by the effluent to size and condition of fish from areas not affected, and (4) to compare food habits of channel catfish in areas affected by the effluent to the food habits of channel catfish in areas not affected.
Contributing Partner: UNT Libraries