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Descriptions, Life History and Case-Building Behavior of Culoptila cantha (Trichoptera: Glossosomatidae) in the Brazos River, Texas

Description: Larval, pupal and adult samples of Culoptila cantha, from a large riffle of the Brazos River in north-central Texas from January, 1995 to March, 1997, indicated a predominately trivoltine cycle during both years; the over-wintering generation spanned 6-7 months and warm-season generations spanned 2-3 months. Eggs, larvae of all instars, larval cases, case reconstruction progression and behavior, pupae, and adults are described.
Date: August 1997
Creator: Houghton, David Charles
Item Type: Refine your search to only Thesis or Dissertation
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Development and Application of an Assessment Protocol for Watershed Based Biomonitoring

Description: With numerous bioassessment methodologies available, a regional protocol needs to be developed to ensure that results are comparable. A regional assessment protocol was developed that includes collecting five benthic macroinvertebrate samples, identifying organisms to genus, and calculating the following metrics: Number of Taxa, Total Number of Individuals, Simpson's Diversity Index, Shannon's Diversity Index, Percent Contribution of Dominant Taxa, Hilsenhoffs Biotic Index, and Percent Contribu… more
Date: May 1998
Creator: Schwartz, Joseph Howard
Item Type: Refine your search to only Thesis or Dissertation
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Development of a Watershed Prioritization Strategy Using Remote Sensing and the Geographic Resource Analysis Support System. Case study: City of Carrollton, Texas

Description: This study used a geographic information system (GIS) and an empirical pollutant load model to estimate average annual pollutant loads contained in storm water charges from the City of Carrollton, Texas. The Geographic Resource Analyses Support System (GRASS) was used to create a number of spatial data layers as input variables to a model that estimates loads in Kilograms/Hectare/Year, and Kilogram/Basin/Year. Average annual pollutant loads for twelve pollutants were derived from average annual… more
Date: December 1996
Creator: Coffey, Jeffery M. (Jeffery Morgan)
Item Type: Refine your search to only Thesis or Dissertation
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Development of Range Condition Classes for Coleman County, Texas

Description: This paper deals with a study of the rangelands in Coleman County just west south and west of the Western Cross Timbers of Texas. This problem consists of classifying certain rangelands in this area according to whether they are excellent, fair, good, or poor, the chief basis for which is their deterioration.
Date: June 1951
Creator: McMinn, Philip Morris
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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Distribution of a Novel Gram Negative, Capsule-Forming Bacterium

Description: A novel Gram negative, capsule-forming bacterium was previously isolated in Dr. G. Roland Vela's laboratory. The distribution of this bacterium in soils from various locations was investigated. Soil samples from 188 locations around the world were examined. Isolates of the bacterium were obtained from 50 of these soils, with 48 of the isolates found in soils from the southwestern United States and northern Mexico. This suggests that this region is the natural habitat of the bacterium. The other… more
Date: December 1997
Creator: Hughes, Roxana Bejarano
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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Distribution of Phosphates in a Sewage Plant and its Receiving Waters

Description: The purpose of this paper is to detail the distribution and quantity of soluble phosphates in an activated sludge plant, its discharge creek, and receiving reservoir. The resultant analyses and comparison of data should provide some better understanding of the fate of phosphorus in a Southwestern waterway system.
Date: May 1969
Creator: Hansard, John D.
Item Type: Refine your search to only Thesis or Dissertation
Location: None
open access

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

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 affec… more
Date: December 1972
Creator: McNeely, David L.
Item Type: Refine your search to only Thesis or Dissertation
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Documentation of Biodiversity Impacts (Including Cumulative Biodiversity Impacts) in Environmental Impact Statements

Description: In the United States, biodiversity impact assessment has historically received little attention. Responding in 1993, the Council on Environmental Quality (CEQ) released guidelines on incorporating biodiversity into environmental impact assessment under the National Environmental Policy Act of 1969. The objectives of the study here were to identify the level of documentation of biodiversity impact assessment in sample Environmental Impact Statements (EISs); identify whether in the years followin… more
Date: August 1998
Creator: Bhatia, Sarika
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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The Dynamics of a Planktonic Microcrustacean Community in a Small North Central Texas Pond Ecosystem

Description: Seven species of planktonic microcrustacea were identified from the North Texas State University Golf Course Pond. Total adult microcrustacean community density, biomass and biocontent, and seasonal cycles of each species were compared with northern populations. Species diversity and evenness indices were highest in summer and lowest in spring. Variations in microcrustacean density showed a positive correlation with density of phytoplankton. Temperature had a direct effect on metabolic rates of… more
Date: December 1976
Creator: Smith, George Arthur
Item Type: Refine your search to only Thesis or Dissertation
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Ecological Association Between the Red-Cockaded Woodpecker and Southern Pine Beetle in the Homochitto National Forest: a Geographic Information System Approach

Description: Since the introduction of management practices by the Forest Service to stabilize red-cockaded woodpecker (RCW) populations, the number of cavity trees killed by southern pine beetles (SPB) has increased. A model of the landscape ecology of RCW and SPB in the Homochitto National Forest was created using data collected from the Forest Service and Global Atmospherics. The conclusions of the study were that the RCW and SPB utilize the same type of habitat and the stand hazard maps are an accurate … more
Date: December 1998
Creator: Skordinski, Karen R. (Karen Renee)
Item Type: Refine your search to only Thesis or Dissertation
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An Ecological Study of the Pine Vole, Microtus Pinetorum, in Northeast Texas

Description: This study dealt with the life history and population dynamics of the pine vole, Microtus pinetorum. In the past there has been a void of ecological material concerning this small mammal in the southwestern region of its range. From November, 1969, through February, 1970, a survey was conducted in Marion County and Harrison County, Texas, to determine the most suitable habitat for an ecological study of Microtus pinetorum. A study was then initiated in March, 1970, and continued through March, … more
Date: August 1971
Creator: Greer, Roy E.
Item Type: Refine your search to only Thesis or Dissertation
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An Ecological Survey of the Herpetofauna of Palo Pinto County, Texas

Description: The purpose of this research was to compile a presence list of reptiles and amphibians that occur in Palo Pinto County, Texas, and to investigate the ecological distributions and zoogeographic affinities of these herpetiles. The study area was chosen primarily because of its location in North Central Texas and its rugged topography, which sets it apart from the surrounding area.
Date: August 1969
Creator: Porter, Stuart T.
Item Type: Refine your search to only Thesis or Dissertation
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An Ecological Survey of the Reptiles and Amphibians of Wise county, Texas

Description: The purpose of this study was to record the relationships between the reptiles and amphibians of Wise County and the ecological subdivisions of the area. Wise County was chosen because of the heterogenity of the area and because of its proximity to other counties which have been previously and similarly studied.
Date: January 1970
Creator: Welch, Donald A.
Item Type: Refine your search to only Thesis or Dissertation
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Effects of Deepwater Horizon Crude Oil on Visual Function in Teleost Fishes

Description: The Deepwater Horizon oil spill released millions of barrels of oil into the Gulf of Mexico, impacting economically and ecologically important fishes. Polycyclic aromatic hydrocarbons (PAHs) present in the oil have been shown to cause developmental impairments in early life stage fishes, such as morphological and behavioral changes related to eye formation and visual processing following PAH exposure. Prior research reported reduced eye growth in open water, pelagic species, as well as reduce… more
Date: August 2018
Creator: Magnuson, Jason T
Item Type: Refine your search to only Thesis or Dissertation
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The Effects of Hexadecanol on the Microbiota of Lake Hefner

Description: It seemed desirable to investigate more fully the effect of hexadecanol on the microbial population of a reservoir. It was the purpose of this investigation to determine the effect of hexadecanol on the micro-biota of Lake Hefner, to ascertain which organisms were stimulated by hexadecanol both in the laboratory and the reservoir, and to investigate the degradation of hexadecanol by microorganisms selected from Lake Hefner.
Date: May 1968
Creator: Dickson, Kenneth L.
Item Type: Refine your search to only Thesis or Dissertation
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The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree Establishment

Description: This study examined the effects of replicating woodland soil surface horizonation on the nutrient status of underlying soils and the initial establishment and growth of trees. A total of 283 container grown trees were planted in a bufferzone around a future landfill site. Control amendments consisted of an 8 cm layer (0.5 m3) of wood chips applied in a circular area of 4.6 m2 around the trees' planting pit. For the treatment, a 2.5 cm layer of composted biosolids (0.15 m3 or 80 Mg/ha) was appli… more
Date: May 1999
Creator: Thuesen, Kevin (Kevin Andrew)
Item Type: Refine your search to only Thesis or Dissertation
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