This system will be undergoing maintenance Monday, January 23 from 8:00 AM to 12:00 PM CST.

  You limited your search to:

  Partner: UNT Libraries
 Country: United States
 Degree Discipline: Biology
 Collection: UNT Theses and Dissertations
Ecological Distribution of the Herpetofauna of Montague County, Texas

Ecological Distribution of the Herpetofauna of Montague County, Texas

Date: August 1969
Creator: Moulton, Bruce A.
Description: The purpose of this study was to make a preliminary study of the herpetofauna of Montague County in relation to ecological distribution. Also taken into consideration were the zoogeographic relationships of the various species.
Contributing Partner: UNT Libraries
An Ecological Study of the Pine Vole, Microtus Pinetorum, in Northeast Texas

An Ecological Study of the Pine Vole, Microtus Pinetorum, in Northeast Texas

Date: August 1971
Creator: Greer, Roy E.
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, 1971, on an undisturbed marsh five miles south of Marshall, Harrison County, Texas.
Contributing Partner: UNT Libraries
An Ecological Survey of the Herpetofauna of Palo Pinto County, Texas

An Ecological Survey of the Herpetofauna of Palo Pinto County, Texas

Date: August 1969
Creator: Porter, Stuart T.
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.
Contributing Partner: UNT Libraries
An Ecological Survey of the Reptiles and Amphibians of Wise county, Texas

An Ecological Survey of the Reptiles and Amphibians of Wise county, Texas

Date: January 1970
Creator: Welch, Donald A.
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.
Contributing Partner: UNT Libraries
Edaphic Factors Which Control the Distribution of the Common Mesquite, Prosopis Chilensis (Molina) Stuntz in Denton County, Texas

Edaphic Factors Which Control the Distribution of the Common Mesquite, Prosopis Chilensis (Molina) Stuntz in Denton County, Texas

Date: 1942
Creator: Steph, Harlan J.
Description: This paper deals with the distributional outgrowths of Prosopis chilensis (Molina) Stuntz, the common mesquite, in Denton County, Texas.
Contributing Partner: UNT Libraries
The Effects of Hexadecanol on the Microbiota of Lake Hefner

The Effects of Hexadecanol on the Microbiota of Lake Hefner

Date: May 1968
Creator: Dickson, Kenneth L.
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.
Contributing Partner: UNT Libraries
The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree Establishment

The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree Establishment

Date: May 1999
Creator: Thuesen, Kevin (Kevin Andrew)
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 applied in a circular area of 4.6 m2 around the trees' planting pit followed by an 8 cm layer (0.5 m3) of wood chips. The results indicate that the replication of woodland soil surface attributes using composted biosolids can significantly improve the nutrient status of underlying soil. Some significant effects were seen under control conditions, too. However, the effects on tree establishment and growth parameters were, for the most part, not statistically significant.
Contributing Partner: UNT Libraries
Eutrophic Levels of Different Areas of a Reservoir: A Comparative Study

Eutrophic Levels of Different Areas of a Reservoir: A Comparative Study

Date: August 1970
Creator: Hendricks, Albert C.
Description: It was the purpose of this investigation to attempt to demonstrate if differences in eutrophic levels existed among selected areas of Garza-Little Elm, and to demonstrate the role that sediments play in affecting eutrophication.
Contributing Partner: UNT Libraries
Evaluating Fish Impingement and Entrainment at the Comanche Peak Steam Electric Station

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

Date: May 1996
Creator: Bauml, George A. (George Arthur)
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 were performed on Squaw Creek Reservoir to help assess impact. It was determined that the losses due to impingement and entrainment have no adverse impact upon the fish population of Squaw Creek Reservoir.
Contributing Partner: UNT Libraries
Evaluation in Soil Moisture in Soil and Water Conservation Practices in Denton, Texas

Evaluation in Soil Moisture in Soil and Water Conservation Practices in Denton, Texas

Date: 1940
Creator: Rylander, Halley G.
Description: This investigation has attempted to show that soil and water conservation practices do increase the amount of soil moisture in five of Denton County, Texas soils: Denton clay, Durant clay, San Saba clay, Kirvin fine sandy loam, and Tabor fine sandy loam.
Contributing Partner: UNT Libraries
Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX

Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX

Date: May 1996
Creator: Baerenklau, Amy L. (Amy Lyn)
Description: The City of Denton Pecan Creek Wastewater Treatment Facility has periodically failed effluent toxicity testing. A Toxicity Identification Evaluation has determined that Diazinon in the effluent is contributing to the observed toxicity. Chlorpyrifos is also implicated as a factor. The City of Denton constructed a half acre experimental wetland to remove Diazinon related toxicity. Results from spiking and microcosm experiments indicate that the wetland can reduce the Diazinon.
Contributing Partner: UNT Libraries
An Evaluation of the United States Soil Conservation Service Program of Grassland Recovery on the Land Utilization Project in Wise county, Texas

An Evaluation of the United States Soil Conservation Service Program of Grassland Recovery on the Land Utilization Project in Wise county, Texas

Date: August 1952
Creator: Hyman, Ruel Richard
Description: This investigation was undertaken in order to evaluate the United States Soil Conservation Service program of grassland recovery on the land utilization project in Wise County, Texas.
Contributing Partner: UNT Libraries
The Fecundity of the Bluegill (Lepomis Macrochirus) in Certain Small East Texas Reservoirs

The Fecundity of the Bluegill (Lepomis Macrochirus) in Certain Small East Texas Reservoirs

Date: 1949
Creator: Estes, Charles M.
Description: A study of reproduction and spawning habits of the bluegill in a particular lake must include adequate samples for each period of the year. This will make it possible to determine the number of eggs in each spawn and the frequency of spawning. The number of spawns and average egg production for various sized fish shows the pattern of activity and makes possible further basic research.
Contributing Partner: UNT Libraries
Fitness-Related Alterations in Blood Pressure Control: The Role of the Autonomic Nervous System

Fitness-Related Alterations in Blood Pressure Control: The Role of the Autonomic Nervous System

Date: December 1986
Creator: Smith, Michael Lamar, 1957-
Description: Baroreflex function and cardiovascular responses to lower body negative pressure during selective autonomic blockade were evaluated in endurance exercise trained (ET) and untrained (UT) men. Baroreflex function was evaluated using a progressive intravenous infusion of phenylephrine HCL (PE) to a maximum of 0.12 mg/min. Heart rate, arterial blood pressure, cardiac output and forearm blood flow were measured at each infusion rate of PE. The reduction in forearm blood flow and concomitant rise in forearm vascular resistance was the same for each subject group. However, the heart rate decreases per unit increase of systolic or mean blood pressure were significantly (P<.05) less in the ET subjects (0.91 ± 0.30 versus 1.62 ± 0.28 for UT). During progressive lower body negative pressure with no drug intervention, the ET subjects had a significantly (P<.05) greater fall in systolic blood pressure (33.8 ± 4.8 torr versus 16.7 ± 3.9 torr). However, the change in forearm blood flow or resistance was not significantly different between groups. Blockade of parasympathetic receptors with atropine (0.04 mg/kg) eliminated the differences in response to lower body negative pressure. Blockade of cardiac sympathetic receptors with metoprolol (0.02 mg/kg) did not affect the differences observed during the control test. It was ...
Contributing Partner: UNT Libraries
Food, Feeding Selectivity, and Ecological Efficiencies of Fundulus notatus (Rafinesque) (Osteichthyes; Cyprinodontidae)

Food, Feeding Selectivity, and Ecological Efficiencies of Fundulus notatus (Rafinesque) (Osteichthyes; Cyprinodontidae)

Date: August 1970
Creator: Atmar, Gerald Legare
Description: This study was made to further define the trophic dynamics of Fundulus notatus by determining its ration composition under natural conditions, measuring feeding selectivity under various laboratory conditions of prey-species composition and availability, and determining the efficiencies with which F. notatus utilizes ingested chironomid larvae.
Contributing Partner: UNT Libraries
Food Habit Analysis of the Two Species of Texas Crappie

Food Habit Analysis of the Two Species of Texas Crappie

Date: 1941
Creator: Mitchell Glenn C.
Description: This study is based upon information taken from stomach analysis of 302 black crappie and 561 white crappie; the following data will be presented: 1. Food of adults and fingerlings; 2. Diet variation in relation to food availability; 3. Seasonal variation of feeding habits; 4. Diet variation in relation to size of crappie. Collections were made from ten lakes located in North, East, Central, and South Texas.
Contributing Partner: UNT Libraries
Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas

Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas

Date: May 1972
Creator: Alcoze, Thomas M.
Description: The coexistence of Dipodomys ordii and Perognathus hispidus with Peromyscus maniculatus and Reithrodontomys montanus was studied in a grassland association of central Texas. The food habits of these species were compared with information from habitat vegetation analysis in an effort to determine food selectivity and the amount and importance of niche overlap and competition among these rodents.
Contributing Partner: UNT Libraries
Food Habits of Stoneflies (Plecoptera) in the Gunnison and Dolores Rivers, Colorado

Food Habits of Stoneflies (Plecoptera) in the Gunnison and Dolores Rivers, Colorado

Date: August 1976
Creator: Fuller, Randall L.
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. Pteronarcids fed predominantly on detritus. Dietary overlap of predators was greatest in the Gunnison River, with subtle mechanisms such as prey species and size selectivity, temporal succession and seasonal shifts to detritus-plant material in some, providing reduction of competition. A more complete partitioning of prey resources was evident in the Dolores River.
Contributing Partner: UNT Libraries
Genetic Differentiation of the Geomys Pocket Gopher Complex of Texas

Genetic Differentiation of the Geomys Pocket Gopher Complex of Texas

Date: August 1988
Creator: Block, Scott B. (Scott Bishop)
Description: Genetic variation was analyzed for populations of seven taxa comprising four cytotypes of the Geomys bursarius chromosome complex, including G. b. major, G. b. knoxjonesi, and the Edwards Plateau taxa, G. b. llanensis and G. b. texensis. Genetic relationships of the Edwards Plateau gophers with other taxa and between themselves were examined. Genetic similarity, number of fixed allelic differences, and ectoparasite distribution indicate the Edwards Plateau gophers are a distinct gene pool. Isolation of the Edwards Plateau taxa precludes contact zone analysis. However, genetic differentiation is typical of that between other species of Geomys, and the Edwards Plateau taxa should be recognized as G. texensis. Distributions of allelic frequencies indicate little justification in retaining the subspecific status of the Edwards Plateau forms.
Contributing Partner: UNT Libraries
Genic Differentiation and Evolution in the Ground Squirrel Subgenus Ictidomys (Spermophilus)

Genic Differentiation and Evolution in the Ground Squirrel Subgenus Ictidomys (Spermophilus)

Date: December 1975
Creator: Cothran, E. Gus, 1951-
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 definition of semispecies. Analysis of electrophoretic variation at 29 genetic loci indicated close genetic relationships between these species. Evolution in Ictidomys appears to be linked with Pleistocene events, and speciation appears to have occurred within the last 155,000 years.
Contributing Partner: UNT Libraries
Geographic Variation in Chromosomes and Morphology of Peromyscus Maniculatus in Texas and Oklahoma

Geographic Variation in Chromosomes and Morphology of Peromyscus Maniculatus in Texas and Oklahoma

Date: August 1972
Creator: Caire, William, 1946-
Description: This study was initiated after finding two chromosomal types of Peromyscus maniculatus north and south of the Red River in Texas and Oklahoma. The problem was to explain the chromosomal variations and their implications to the systematics of the grassland subspecies of P. maniculatus in this region.
Contributing Partner: UNT Libraries
A Grassland Evaluation of Eastland County, Texas

A Grassland Evaluation of Eastland County, Texas

Date: 1951
Creator: Durham, Norman Nevill
Description: This investigation has had for its purpose the determination of first, all members of the Gramineae (Grass) family found in the county; second, the incidence of each species with the various types of soil; third, the grazing value of each species; fourth, the life span of the parent plants; fifth, the present grassland status; and sixth, the potentialities of developing desirable grassland.
Contributing Partner: UNT Libraries
A Grassland Evaluation of the W. A. McKamy Ranch, Denton and Wise Counties, Texas

A Grassland Evaluation of the W. A. McKamy Ranch, Denton and Wise Counties, Texas

Date: 1950
Creator: Meacham, William Ross
Description: This problem consists of classifying the four major pastures of the McKamy ranch into McConnell's four categories, by means of examinations based on these qualities and characteristics.
Contributing Partner: UNT Libraries
Herpetology of the Amistad Reservoir Area, Val Verde County, Texas

Herpetology of the Amistad Reservoir Area, Val Verde County, Texas

Date: January 1969
Creator: Devine, Michael C.
Description: The Amistad Reservoir in southern Val Verde County, Texas will impound a considerable amount of surface water in a semi-arid region in which natural surface water is scarce. Construction of the dam began in 1963 and the reservoir began to fill in the summer of 1968. This large impoundment could have a considerable ecological impact on the area. The purpose of this research was to study the ecological distribution and zoogeographic affinities of the herpetofauna and to establish an ecological baseline against which any future changes could be measured.
Contributing Partner: UNT Libraries