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Individual, Social, and Seasonal Behavior of the Thirteen-Lined Ground Squirrel (Spermophilus tridecemlineatus)

Description: The purpose of this study is to provide a qualitative, detailed description of individual and social behavior in a free-living population of thirteen-lined ground squirrels. Behavioral differences in relation to various periods of the annual cycle are also evaluated.
Date: January 1970
Creator: Wistrand, Harry E.
Item Type: Refine your search to only Thesis or Dissertation
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The Vertical Stratification of the Macrobenthos in the Brazos River, Texas

Description: Quantification of stream macrobenthos populations has remained a perplexing problem in rivbrine ecology, despite numerous attempts at improvement. This is in part due to well documented variations in chemical and physical parameters locally and geographically, and resultant adapted macrobenthos populations. Southwood (1968) and Hynes (1970a) have reviewed the various sampling techniques developed'for the census of lotic macrobenthos populations. Needham and Usinger (1956), Chutter (1969), and o… more
Date: December 1973
Creator: Poole, Walton Charles
Item Type: Refine your search to only Thesis or Dissertation
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The Distribution of Pathogenic Pseudomonas aeruginosa in Sewage

Description: The purpose of this study was to extend our understanding of the ecological relationships of P. aeruginosa by investigating the differences or similarities between the strains of this organism found in sewage and those found as pathogens in human infections. This research was approached by comparing the serological types of P. aeruginosa isolated from sewage contaminated waters in Argentina (South America) to those isolated from sewage contaminated waters in Texas. They were typed with sera obt… more
Date: May 1974
Creator: Labay, Joseph Edward
Item Type: Refine your search to only Thesis or Dissertation
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The Stoneflies (Plecoptera) of Texas

Description: An illustrated key to the adults and known nymphs of Texas Plecoptera is provided. Species accounts, including geographic distribution within Texas, and biological notes are given. Of the twenty-seven species of Plecoptera known from Texas, six are new state records. TWo species new to science, Isoperla jewetti and Isoperla coushatta are described. Taeniopteryx starki Stewart and Szczytko, Zealeuctra arnoldi Ricker and Ross, and Zealeuctra hitei Ricker and Ross are endemic to the Edwards Platea… more
Date: May 1975
Creator: Szczytko, Stanley W.
Item Type: Refine your search to only Thesis or Dissertation
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The Detection of Poliovirus in Denton Sewage by Immunofluorescence and Immunodiffusion Techniques

Description: Several final sewage effluents from the Denton Disposal Plant were demonstrated to contain Poliovirus types II and III. Pleated encapsulated filters at pH3.5 enhanced the recovery of the Poliovirus at a higher tier in comparison with nitrocellulose filter (Millipore) and glass fiber filter of pore size 0.45u. This thesis explores problems that face us today in our quest to eliminate viral pathogens from the natural and waste water needed for human, domestic, and industrial consumption. Prelimin… more
Date: August 1975
Creator: Olaiya, Felix Ayodele
Item Type: Refine your search to only Thesis or Dissertation
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Genic Differentiation and Evolution in the Ground Squirrel Subgenus Ictidomys (Spermophilus)

Description: The genetic structure of 26 natural populations of three species (S. tridecemlineatus, S. mexicanus, and S. spilosoma) of the Ictidomys subgenus of ground squirrels was analyzed using chromosomal and electrophoretic techniques. Chromosomal variation was not observed in S. mexicanus, and only slight karyotypic variation was found in the other two species. Chromosomal evidence indicated hybridization between S. tridecemlineatus and S. mexicanus, placing these species within the classical definiti… more
Date: December 1975
Creator: Cothran, E. Gus, 1951-
Item Type: Refine your search to only Thesis or Dissertation
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Food Habits of Stoneflies (Plecoptera) in the Gunnison and Dolores Rivers, Colorado

Description: Gut contents of 2,500 stonefly nymphs, comprising 10 species, from the Gunnison and Dolores Rivers, Colorado were examined from Dec., 1974-Oct., 1975. Perlidae species were carnivorous feeding primarily on chironomids, mayflies and caddisflies. Seasonal patterns of ingestion and preference varied among species and predator sizes and between rivers. Early instar polyphagous species utilized detritus in the fall, eventually shifting to carnivorous habits as they grew through winter-spring. Pteron… more
Date: August 1976
Creator: Fuller, Randall L.
Item Type: Refine your search to only Thesis or Dissertation
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Comparative Chemistry of Thermally Stressed North Lake and Its Water Source, Elm Fork Trinity River

Description: To better understand abiotic dynamics in Southern reservoirs receiving heated effluents, water was analyzed before and after impoundment in 330 ha North Lake. Macronutrients, metals, and chlorinated hydrocarbons were measured. Concentrations of nutrients and metals in sediments were quantified in this 2 yr study. River water prior to impoundment contained 16 times more total phosphorus, and supported 23 times more Selenastrum capricornutum cells in an algal assay than reservoir water. The reser… more
Date: December 1976
Creator: Sams, Barry L.
Item Type: Refine your search to only Thesis or Dissertation
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The Relation Between Carbon Assimilation and Biomass Dynamics in a Phytoplankton Community

Description: Production dynamics in the phytoplankton community of a mesotrophic Texas reservoir were measured weekly over a four month period using 14C incubation and ATP assay methodologies. Assimilation values of 14C ranged from 0.2 to 45 ug C 1 hr1 - . Significant positive and occasionally negative changes in biomass (i.e. viable organic carbon) were observed in short term (4 hr) in situ incubations juxtapo-sitioned with the 14C experiments; viable organic carbon production, estimated with the ATP assay… more
Date: December 1977
Creator: Wilcox, Douglas P.
Item Type: Refine your search to only Thesis or Dissertation
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Nymphs of the Stonefly (Plecoptera) Genus Taeniopteryx of North America

Description: Nymphs of the 9 Nearctic Taeniopteryx species were reared and studied, 1976-78. Two morphologically allied groupings, the Taeniopteryx burksi-maura, and T. litalonicera- starki complexes corresponded with adult complexes. A key separating 7 species, based primarily upon pigment patterns and abdominal setal arrangements, was constructed. Taeniopteryx lita and T. starki were indistinguishable; T. burksi was separated from T. maurawhen no developing femoral spur was present. This study was based u… more
Date: May 1978
Creator: Fullington, Kate Matthews
Item Type: Refine your search to only Thesis or Dissertation
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Production and Energy Metabolism in Three Benthic Insect Populations in a Small North Central Texas Pond

Description: Annual energy budgets of dominant benthic macro-invertebrates were examined during November 1973 to October 1974 from the benthos of a small pond ecosystem in north-central Texas. Estimates of annual secondary production (Hynes and Coleman 1968) were Procladius s. (Diptera, Chironimidae), 2.4 g m^-2 y^-1 (13 kcal m^-2 y^-1 ); Tendipes decorus (Diptera, Chironomidae), 6.0 g m^-2 y^-1 (40 kcal m^-2 y^-1 ); Brachycercus sp. (Ephemeroptera, Caenidae), 1.9 g m^-2 y^-1 (11 kcal m^-2 y^-1). Energy met… more
Date: May 1978
Creator: Benson, Daniel J.
Item Type: Refine your search to only Thesis or Dissertation
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Thermal Selection at an Enzyme Locus in Populations of the Red Shiner, Notropis lutrensis, Receiving Hypolimnion Effluents from a Reservoir

Description: Genetic variation was examined at 19 loci encoding enzymatic and general proteins Notropis lutrensis from the Brazos River in Texas. The thermal regime of the Brazos River below Possum Kingdom Reservoir is altered due to the release of water from the hypolimnion. Summer water temperatures fluctuate as much as 7^oC. Levels of heterozygosity at the malate dehydrogenase-2 locus were correlated with the degree of water temperature fluctuation at each locality. The isozymes from three homozygous pat… more
Date: May 1978
Creator: Richmond, M. Carol
Item Type: Refine your search to only Thesis or Dissertation
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Trophic Structure and Energy Flow in a Texas Pond

Description: Annual energy flow and mean annual biocontent of eighteen compartments were determined for a 0.94 ha north central Texas pond ecosystem. Annual primary production was 7,780 kcal m^-2 yr^-2, and community production-to-respiration ratio was 1.49. One-third of annual primary production accumulated on the substrate as silt and sedimentation. Community production, production-respiration ratio, and biocontents of all compartments except aquatic insects were large in summer, small in winter. Bioconte… more
Date: August 1978
Creator: Childress, William M.
Item Type: Refine your search to only Thesis or Dissertation
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Distribution, Abundance, and Food Habits of Larval Fish in a Cooling Reservoir

Description: Analysis of larval fish collected at four stations in a 330-ha cooling reservoir indicated Dorosoma spp. were most numerous at all stations, followed by Lepomis spp. and Percina Macrolepida. Largest numbers and greatest diversity of larval fish were found at the station least affected by thermal effluent; the mid-lake station provided the smallest numbers and least diversity. The two warmwater stations were intermediate, with similar numbers and diversity. Diversity and abundance of zooplankton… more
Date: December 1978
Creator: Mitterer, Lana Gayle
Item Type: Refine your search to only Thesis or Dissertation
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Pelagic Phytoplankton and Physicochemical Correlates for Lake Texoma

Description: An analysis and correlation of phytoplankton communities with physicochemical data from 3 sites in Lake Texoma was conducted to supplement time-series data. Water and phytoplankton were sampled monthly, March, 1976-February, 1977. Simple correlations were run between all physicochemical parameters and phytoplankton standing crop from the 3 sites. Multiple linear regression analyses were used to develop equations predictive of phytoplankton standing crop and chloride concentration. Minerals leac… more
Date: December 1978
Creator: McCullough, William P.
Item Type: Refine your search to only Thesis or Dissertation
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Seasonal and Spatial Variability of the Microcrustacean Community in Lake Texoma, Texas and Oklahoma

Description: Twenty-eight species of zooplankton were identified from Lake Texoma. Seasonal density of the overall microcrustacean community and seasonal cycles of individual species were compared with northern populations and any available literature from the Southwest. Cycles of occurrence and abundance were similar to those observed in northern populations but tended to occur earlier in the year due to higher temperatures. Spatial distributions within the reservoir were heavily influenced by nutrient and… more
Date: August 1980
Creator: Crist, Lawrence W.
Item Type: Refine your search to only Thesis or Dissertation
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Population Dynamics of Macrobenthos in a Regulated Stream 1970-71 and 1978

Description: Stability of the macrobenthic community in a regulated section of the Brazos River, Texas, was evaluated. Physicochemical data and information on spatial distribution of macrobenthos were collected. Populations of two invertebrate species, Isonychia sicca and Neoperla clymene, had been greatly reduced since 1970-71 and I. sicca had been practically eliminated from this section of the Brazos. Three other insect populations, Choroterpes mexicanus, Cheumatopsche campyla and Cheumatopsyche lasia, h… more
Date: August 1981
Creator: Coulter, James D. (James Duard)
Item Type: Refine your search to only Thesis or Dissertation
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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… more
Date: August 1983
Creator: Feminella, Jack W. (Jack William)
Item Type: Refine your search to only Thesis or Dissertation
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Drumming Behavior of Selected North American Stoneflies (Plecoptera)

Description: Drumming is first described for five North American stonefly species, Acroneuria evoluta, Doroneuria baumanni, Isoperla namata, Chernokrilus misnomus, and Pictetiella expansa. Signals of Acroneuria lycorias, Phasganophora capitata and Isoperla signata are further described. Drumming was not recorded from Amhinemura delosa. Signals of A. evoluta are the most complex yet recorded in Plecoptera. Doroneuria baumanni, P. expanse, C. misnomus and P. capitata have 2-way exchanges. Male D. baumanni pro… more
Date: December 1983
Creator: Maketon, Monchan
Item Type: Refine your search to only Thesis or Dissertation
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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… more
Date: May 1984
Creator: Hinman, Mark L.
Item Type: Refine your search to only Thesis or Dissertation
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Emergence, Growth, Drift and Microdistribution of Stoneflies (Plecoptera) in an Ozark Foothills Stream, Delaware County

Description: Adult stonefly emergence, nymphal growth, drift and microdistribution were examined in Battle Branch, a secondorder, spring-fed stream, from November, 1982 to May, 1984. Adults of 22 species emerged successionally, with specific adults present every month. Searching emergent objects and the stream margin was best for collection of winter and early spring emerging species. Sweeping the streamside and light trapping were most efficient for late spring and summer emerging species. Nymphal growth f… more
Date: May 1985
Creator: Ernst, Mark R. (Mark Richard)
Item Type: Refine your search to only Thesis or Dissertation
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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… more
Date: August 1985
Creator: Entezami, Azam A. (Azam Alsadat)
Item Type: Refine your search to only Thesis or Dissertation
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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… more
Date: May 1987
Creator: Dodson, Susan Boyd
Item Type: Refine your search to only Thesis or Dissertation
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