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open access

A Two Semester Life Science Syllabus for Use in Texas Public Schools with Seventh Grade Students

Description: The problem of using a state adopted textbook written to apply to a large body of students with varying interests and needs was overcome by using a detailed syllabus that arranged course content in a meaningful sequence that appealed to student interest. The outlined syllabus prepared a two semester life science curriculum to be used by the teacher to guide lesson planning. Both semesters were divided into three units each. Materials included in the syllabus were given to actual student groups … more
Date: May 1995
Creator: Edwards, Gail G. (Gail Graham)
Item Type: Refine your search to only Thesis or Dissertation
open access

Underwater Optical Properties of Lake Texoma (Oklahoma-Texas) Using Secchi Disk, Submarine Photometer, and High-Resolution Spectroscopy

Description: The underwater optical climate of Lake Texoma was measured at eleven fixed stations from August 1996 to August 1997. Secchi transparency and submarine photometry characterized seasonal and spatial values of secchi depth (SD), vertical attenuation coefficient (η''), and depth of euphotic zone (Zeu). Indices of Zeu:SD and η'' × SD were compared with universally applied values derived from inland and coastal waters. Turbidity explained 76% of the variation (p = 0.0001) of η'' among water quality p… more
Date: August 1998
Creator: Rolbiecki, David A. (David Alan)
Item Type: Refine your search to only Thesis or Dissertation
open access

Temporal and Spatial Comparisons of Ambient Toxicity of the Trinity River in Relationship to an Effluent

Description: A toxicological study was initiated because of concerns about allegations that the Texas Water Commission that effluent from the Dallas Central Wastewater Treatment Plant, which discharges into the Trinity River, was affecting downstream water quality. Monthly, flow-weighted composite effluent samples were collected. Grab samples were also collected upstream and downstream from the effluent from April 1989 to August 1991. Toxicity tests were conducted on these samples using Ceriodaphnia dubia a… more
Date: December 1993
Creator: Hall, David B., 1958-
Item Type: Refine your search to only Thesis or Dissertation
open access

Assessing Regional Gully Erosion Risk: A Remote Sensing and Geographic Information Systems Approach

Description: Gully erosion has been established as a major source of sediment pollution in the upper Trinity River watershed in north-central Texas. This fact, along with a lack of models appropriate for a large-area gully erosion analysis established a need for a gully erosion study in the upper Trinity basin. This thesis project attempted to address this need by deriving an index indicative of gully erosion risk using remote sensing and geographic information systems (GIS) methodology. In context of previ… more
Date: August 1995
Creator: Sill, Paul E. (Paul Eric)
Item Type: Refine your search to only Thesis or Dissertation
open access

An Assessment of the Use of Seeding, Mowing, and Burning in the Restoration of an Oldfield to Tallgrass Prairie in Lewisville, Texas

Description: An examination of the effectiveness of seeding, burning, and mowing in the reestablishment of tallgrass prairie species on overgrazed and abandoned pastureland. The study site is a 20 acre tract on U.S. Corps of Engineers land below Lake Lewisville in Denton County, Texas. The site was partitioned into thirty-nine 40 by 40 meter plots with seeding (carried out in 1996) and management treatment (burning, mowing, and no maintenance carried out in 1998) randomly applied following a two level desig… more
Date: August 1999
Creator: Windhager, Steven
Item Type: Refine your search to only Thesis or Dissertation
open access

Monitoring Watershed Health in the Upper Trinity River Basin, North Central Texas

Description: This study conducts watershed analysis using biological and geo-spatial techniques. Incorporating landscape features with biological attributes has been shown to be an effective method of monitoring environmental quality within watersheds. In situ biomonitoring using the Asiatic Clam, Corbicula fluminea, habitat suitability, and water quality data were evaluated for their potential to describe ecological conditions in agricultural and urban areas within the Upper Trinity River watershed. These … more
Date: May 1999
Creator: Csekitz, Jill Diane
Item Type: Refine your search to only Thesis or Dissertation
open access

Physiological Ecology, Population Genetic Responses and Assemblage Stability of Fishes in Two Southwestern Intermittent Stream Systems

Description: Six sites within the Denton and Hickory Creek watersheds were sampled over three years to assess the impact of seasonal intermittent stream conditions on the ichthyofauna. An integrated approach using field and laboratory techniques was employed to evaluate the responses of the fishes.
Date: December 1991
Creator: Rutledge, Charles Jerry, 1941-
Item Type: Refine your search to only Thesis or Dissertation
open access

An Evaluation of Fish and Macroinvertebrate Response to Effluent Dechlorination in Pecan Creek

Description: This study evaluated the effects of chlorinated effluent discharged from the City of Denton, Texas' wastewater treatment plant on Pecan Creek's fish and macroinvertebrate assemblages, and their recovery upon dechlorination. A baseline of ecological conditions was established while chlorine was present in the effluent (June 1993- October 1993), and was evaluated again after dechlorination with sulfur dioxide (October 1993-August 1994). In situ Asiatic clam and fathead minnow ambient toxicity tes… more
Date: May 1995
Creator: Wise, Patricia D. (Patricia Diane)
Item Type: Refine your search to only Thesis or Dissertation
open access

Interspecific Competition Between Hygrophila polysperma and Ludwigia repens, Two Species of Importance in the Comal River, Texas

Description: Hygrophila polysperma is a plant native to Asia that has been introduced into the Comal River, TX and is thriving while Ludwigia repens, a species native to the river appears to be declining. Both plants have similar morphologies and occupy similar habitats in the river. Two plant competition experiments were conducted to examine the competitive interactions between the two species. First, an experimental design was developed in which established Ludwigia plants were 'invaded' by sprigs of Hygr… more
Date: May 1999
Creator: Francis, Matthew D.
Item Type: Refine your search to only Thesis or Dissertation
open access

Evaluating Fish Impingement and Entrainment at the Comanche Peak Steam Electric Station

Description: This study was designed to determine if impingement and entrainment by cooling water intake at the Comanche Peak Steam Electric Station have an adverse impact upon the Squaw Creek Reservoir fish population. The yearly impingement of fish was estimated to be 262,994 of 14 species. The threadfin shad (Dorosoma petenense) accounted for 96% of this total. Entrainment of eggs and larvae for a five month period was estimated to be 15,989,987 and 42,448,794 respectively. Two fish population studies we… more
Date: May 1996
Creator: Bauml, George A. (George Arthur)
Item Type: Refine your search to only Thesis or Dissertation
open access

Hooking Mortality of Largemouth Bass Caught on Controversial Artificial Lures and Live Bait : Lake Ray Roberts, Texas

Description: A total of 192 largemouth bass were caught at Lake Ray Roberts, Texas (1995) to investigate five controversial bass angling techniques relative to hooking mortality. The bait types were Texas-rigged scented and non-scented plastic worms, Carolina-rigged scented and non-scented plastic worms, and live golden shiners. Overall hooking mortality was 21.87% and mortality was dependent upon bait type. Highest mortality resulted from the Texas-rigged scented lures, while the lowest mortality was gener… more
Date: May 1996
Creator: Alumbaugh, Andrew E. (Andrew Edward)
Item Type: Refine your search to only Thesis or Dissertation
open access

Responses of Selected Texas Fishes to Abiotic Factors, and an Evaluation of the Mechanisms Controlling Thermal Tolerance of the Sheepshead Minnow

Description: Low oxygen tolerances of ten fishes were estimated using an original nitrogen cascade design, and reciprocally transformed to express responses as ventilated volume necessary to satisfy minimal oxygen demand (L·mg O2^-1). Values ranged from 0.52 to 5.64 L·mg^-1 and were partitioned into three statistically distinct groups. Eight stream fishes showed moderately high tolerances reflecting metabolic adaptations associated with stream intermittency. Juvenile longear sunfish and two mollies comprise… more
Date: May 1994
Creator: Bennett, Wayne A. (Wayne Arden)
Item Type: Refine your search to only Thesis or Dissertation
open access

Biology and Energetics of Tropisternus Lateralis Nimbatus (SAY) (Coleoptera: Hydrophilidae) in a Playa on the Southern High Plains of Texas and Aquatic Coleoptera Diversity from Seven Playas on the Southern High Plains of Texas

Description: A study of the biology of Tropisternus lateralis, a hydrophilid beetle, was conducted during the flood period of a single playa on the Southern High Plains of Texas from early June 1995 through early September 1995. Mechanism of colonization, tolerance/avoidance to drought, larval density, and secondary production were analyzed. T. lateralis colonized playas from surrounding aquatic habitats and avoided drought through aerial dispersion. Once in the playa, larval density increased over time. Se… more
Date: December 1997
Creator: Cook, Robert E. (Robert Edward), 1969-
Item Type: Refine your search to only Thesis or Dissertation
open access

Stock and Species Identification of Selected Marine Fishes and Shellfishes Using Allozyme Analysis and Isoelectric Focusing: Implications for Texas Fisheries Management

Description: Allozyme frequencies and general protein patterns were surveyed among selected Texas marine fishes and shellfishes to illustrate the application of biochemical genetic techniques to stock and species identification in fisheries management.
Date: May 1992
Creator: King, Timothy L. (Timothy Lee)
Item Type: Refine your search to only Thesis or Dissertation
open access

Assessing the Effects of a Municipal Wastewater Treatment Plant Effluent on Zooplankton, Phytoplankton and Corbicula Flumina in a Constructed Wetland

Description: Wetland wastewater treatment offers low-cost, energy efficient alternatives to conventional wastewater technologies. In this study, an artificial wetland was constructed at the City of Denton, Texas Pecan Creek Water Reclamation Plant to facilitate diazinon removal from treated effluent.
Date: May 1995
Creator: Hymel, Stephanie Ramick
Item Type: Refine your search to only Thesis or Dissertation
open access

An Assessment of Storm Water Toxicity from the Dallas/Fort Worth Metroplex and Denton, Texas

Description: With the advent of national storm water regulations, municipalities with populations greater than 100,000 are required to obtain National Pollutant Discharge Elimination System Permits (NPDES) for storm water discharges. In addition to the sampling required for the permit process, the City of Fort Worth contracted with the University of North Texas' Institute of Applied Sciences to conduct acute toxicity testing using Pimephales prcmelas and Ceriodaphnia dubia on storm water samples received fr… more
Date: August 1995
Creator: Keating, Paul Redmond
Item Type: Refine your search to only Thesis or Dissertation
open access

Plankton Community Response to Dechorination of a Municipal Effluent Discharged into the Trinity River

Description: Chorine is used by the Village Creek Waste Water Treatment Plant to kill pathogenic microorganisms prior to discharge of the effluent into the Trinity River. The residual chlorine in the river impacted aquatic life prompting the U.S. Environmental Protection Agency in December 1990 to require dechlorination using sulfur dioxide. One pre-dechlorination and four post-dechlorination assessments of phytoplankton, periphyton, and zooplankton communities were conducted by the Institute of Applied Sci… more
Date: December 1994
Creator: Bryan, Brynne L. (Brynne Lee)
Item Type: Refine your search to only Thesis or Dissertation
open access

Nesting Ecology of the Dickcissel (Spiza americana) on a Tallgrass Prairie Relict in North Central Texas

Description: Eighty-three species of vascular plants were inventoried on the prairie relict during peak dickcissel nesting. Based on foliar cover and occurrence frequency, the five dominant plants were heath aster (Aster ericoides), eastern gammagrass (Tripsacum dactyloides), little bluestem (Schizachyrium scoparium), sensitive briar (Schrankia roemeriana) and meadow dropseed (Sporobolus asper). Sixty-one percent of dickcissel nests were constructed on or immediately next to three plant species: eastern gam… more
Date: May 1993
Creator: Steigman, Kenneth Lee
Item Type: Refine your search to only Thesis or Dissertation
open access

Habitat Evaluation Procedures at Ray Roberts Lake: an Analysis of the Relationship with Ecological Indicators and a Study of Observer and Temporal Variability

Description: Habitat Evaluation Procedure data gathered at Ray Roberts Lake in 1989 and 1990 were analysed for temporal variability, observer variability and relationships between Habitat Units (HUs) and species density/diversity. observer variability within a group was analysed by cluster analysis and bootstrapping. Five out of 36 sites showed significant differences in Habitat Suitability Index (HSI) values within the group. A nonparametric Mann-Whitney test was used to analyze temporal variability. One o… more
Date: December 1993
Creator: Wattrus, Jane M. (Jane Marie)
Item Type: Refine your search to only Thesis or Dissertation
open access

Biodiversity of Dragonflies and Damselflies (Odonata) of the South-Central Nearctic and Adjacent Neotropical Biotic Provinces

Description: The south-central United States serves as an important biogeographical link and dispersal corridor between Nearctic and Neotropical elements of western hemisphere odonate faunas. Its species are reasonably well known because of substantial collections, but there has been no concerted effort to document the extent of biodiversity and possible geographic affinities of dragonflies and damselflies of this region. The recent discoveries of Argia leonorae Garrison, Gomphus gonzalezi Dunkle and Erpeto… more
Date: May 1999
Creator: Abbott, John C.
Item Type: Refine your search to only Thesis or Dissertation
open access

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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