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Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines May 1981

Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Community succession, the orderly changes a community experiences with time, is considered to be the result of either autogenic or allogenic factors working singularly or in combination. It has been further suggested that, as communities undergo succession, certain biological parameters change in a predictable manner. Examination of members 2 through 4 of the Mississippian (Kinderhook-Osage) Lodgepole Formation of Samaria Mountain, Idaho provides a means to evaluate these concepts.

Within the study section comprised of 125 beds (61.5 m thick), four rock types are recognized. These include: (1) fossiliferous wackestone (78% of beds), which ranges in color from dark-gray (N3) to …


The Energy Expenditure Of Heifers Grazing Crested Wheatgrass Rangeland In West-Central Utah, Kris M. Havstad May 1981

The Energy Expenditure Of Heifers Grazing Crested Wheatgrass Rangeland In West-Central Utah, Kris M. Havstad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The free-roaming ruminant requires energy for the demands of vii grazing, traveling and thermoregulation that are not required by its confined counterpart. Literature estimates of these additional costs range from 10 to 170 percent above maintenance. The uncertain magnitude of this increased demand and the factors that contribute to it impede the ability of the rangeland ruminant nutritionist to establish guidelines for the energy requirements of the free-roaming herbivore. This study was designed to estimate the energy expenditure of yearling Angus heifers while grazing a declining supply of available crested wheatgrass forage (Agropyron cristatum) on rangeland in west-central …


Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat May 1981

Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperatures selected seasonally by adult mountain whitefish were measured in the laboratory in a horizontal gradient. Final preferendum estimates, based on acute (3-hour) preference tests conducted with fish acclimated to 5, 10, and 15 C each season, were 17.7 C (pre-spawning), 11.9 C (post-spawning), 9.9 C (winter), and 16.3 C (spring). Seasonal influence on temperature selection was evident on the basis of differences in final preferenda, covariance analysis of responses of laboratory-acclimated fish, and temperature selection by fish held at ambient river temperatures. Post-spawning and winter groups selected lower temperatures than did pre-spawning and spring groups. Pre-spawning fish selected temperatures …


Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza May 1981

Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Domestic goats were used to modify the growth form of blackbrush, a spinescent shrub occurring in nearly monospecific stands on several million hectares of rangeland in the southwestern United States. The objective of this research was to evaluate goat browsing as a means of improving these rangelands for cattle. Winter goat browsing stimulated spring twig growth from basal and axillary buds which resulted in increased production.

Twig production by heavily browsed plants (>95 percent removal of current season's twigs) was a function of precipitation, soil depth, branch location on the plant, and period of rest after browsing. As precipitation …


Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk May 1981

Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two experiments were conducted in the semi-arid (400 millimeter annual rainfall) Macquarie region of New South Wales, Australia, at the Trangie Agricultural Research Station (31° 59'S; 147° S7'E), to examine (a) the way botanical parameters can be used to separate grazing and climatic impacts on range vegetation, and (b) how this delineation affects application of range science tenets (site, condition and trend) to different pasture types.

Two range sites were studied: Site 1, a light soil type, was dominated by annual grasses, legumes and forbs, whereas perennial grasses (mainly Chloris acieularis and Chloris truncata) dominated the heavy soils of …


Growth-Form Analysis And Paleoecology Of The Corals Of The Late Ordovician Through Mid-Silurian Fish Haven And Laketown Formations, Bear River Range, North-Central Utah, Thomas B. Rich May 1981

Growth-Form Analysis And Paleoecology Of The Corals Of The Late Ordovician Through Mid-Silurian Fish Haven And Laketown Formations, Bear River Range, North-Central Utah, Thomas B. Rich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Morphology of corals of the Late Ordovician through mid-Silurian Fish Haven and Laketown Formations were analyzed to document adaptations to inferred enviromental conditions, i.e., (bathymetry, illumination, sedimentation, currents, and energy), under which their enclosing sediment was deposited. Specimens and data were collected from six sites. Insoluble-residue tests were performed on the corals' matrices.

Individual corallites of radial-lensoidal corals radiate in all directions. Vertical growth, however, was restricted in turbulent conditions. Umbrellic, radial-lensoidal corals feature downward facing corallites, considered to be an adaptation to a well illuminated environment.

On tabular lensoidal corals, constituent corallites faces exclusively upward, an orientation needed under …


Comparison Of Toxicological Models For Evaluation Of Air Pollutants: Response Of The Pulmonary Alveolar Macrophage To Hexavalent Chromium, Jennifer Baker Galvin May 1981

Comparison Of Toxicological Models For Evaluation Of Air Pollutants: Response Of The Pulmonary Alveolar Macrophage To Hexavalent Chromium, Jennifer Baker Galvin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was designed to accomplish two primary objectives: (1) to compare two test methods commonly used to evaluate toxicity of inhaled air pollutants, and (2) to observe the response as measured by each of the methods, of pulmonary alveolar macrophages exposed to 2μg hexavalent chromium.

The first method evaluated featured use of intratracheal injections to simulate live inhalation exposures, and the second required exposure of macrophages cultured on petri plates. Pulmonary alveolar macrophages harvested from Long Evans rats were used. The two cell function parameters measured in the evaluations were chemiluminescence and oxygen consumption (which was determined for cells …


The Transport And Intracellular Distribution Of Iron In The Basidiomycete, Ustilago Sphaerogena, Charles W. Passavant May 1981

The Transport And Intracellular Distribution Of Iron In The Basidiomycete, Ustilago Sphaerogena, Charles W. Passavant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The transport and intracellular distribution of iron in Ustilago sphaerogena via the native siderochrome ferrichrome A has been examined. Evidence is presented which suggests the involvement of deferriferrichrome in iron transport when the metal is supplied to the cell as ferrichrome A. This process requires both oxygen and ATP synthesis and may require a transmembrane electrochemical gradient. Once inside the cell, iron derived from ferrichrome A is rapidly distributed, with a major fraction found in the mitochondria, presumably as heme.

The kinetics of ferrichrome and ferrichrome A uptake have also been investigated. The Km of transport of ferrichrome was …


Support Systems Of Mexican-American Women And Their Attitudes Regarding Infant Feeding, Susan Marie Krantz May 1981

Support Systems Of Mexican-American Women And Their Attitudes Regarding Infant Feeding, Susan Marie Krantz

Loma Linda University Electronic Theses, Dissertations & Projects

This was a descriptive study of 37 recently migrated to the United States, Spanish-speaking, Mexican-American women. Attitudes and support systems associated with their choice to breast or bottle feed their infants were studied. The purpose of this research was to answer the following questions:

1. What are the differences in the attitudes of Mexican- American primiparas who choose to breast feed and those who choose to bottle feed?

2. What are the differences in the practice, recommendations, and proximity of location of significant members of the women's support systems?

Twenty-one breast feeders and 16 bottle feeders were interviewed in Spanish …


The Rhode Island Quahogger: Candidate For The List Of Endangered Species?, James M. Korney Apr 1981

The Rhode Island Quahogger: Candidate For The List Of Endangered Species?, James M. Korney

Marine Affairs Theses and Major Papers

It is the hypothesis of this paper that today the livelihood of the independent Narragansett Bay quahogger is faced with two potentially dangerous threats; water pollution in upper Narragansett Bay and the prospect of an expanding aquaculture industry in the lower bay. Unless the state of Rhode Island properly interprets and enforces existing state legislation to protect the quahoggers interests, his very livelihood will be jeoprodized. This paper will examine the legal, political, economic, and environmental affects of water pollution in upper Narragansett Bay and an expanding aquaculture industry in the lower bay in their relation to the Rhode Island …


Municipal Sewage Treatment: Problems And Considerations, George R. Johnson Apr 1981

Municipal Sewage Treatment: Problems And Considerations, George R. Johnson

Marine Affairs Theses and Major Papers

The coastal areas are vital to the economic and physical well being of the United States. Virtually every facet of our way of life is related in some fashion to these coastal areas. Ocean borne transportation moves not only vast quantities of raw materials, but also many of the intermediate and final products that are then manufactured to their related market areas. Fisheries provide vast amounts of food and employment for many of our people. In addition, the coasts are a continuing source of enjoyment and recreation for millions of our citizens. Coastal waters provide much of the water necessary …


The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1981 [Program, 93th Meeting], Iowa Academy Of Science Apr 1981

The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1981 [Program, 93th Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Abstracts Of Papers, 93rd Session, Iowa Academy Of Science, April 24-25, 1981, Iowa Academy Of Science Apr 1981

Abstracts Of Papers, 93rd Session, Iowa Academy Of Science, April 24-25, 1981, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


A Comparison Of Reproductive Strategies Among Marine Snakes, Cliff A. Lemen, Harold K. Voris Apr 1981

A Comparison Of Reproductive Strategies Among Marine Snakes, Cliff A. Lemen, Harold K. Voris

School of Natural Resources: Faculty Publications

(1) Gravid females representing fourteen species of marine snakes were collected from four localities along the coast of Malaysia in 1975. The average clutch size ranged from 2.9 to 17.8 but most species had between three and seven young. The number of young produced and the size of gravid Lapemis hardwickii differed significantly at two sites in the Straits of Malacca. Eight species showed a significantly positive relationship between the number of oviducal eggs and female weight. The rate of infertility among ten species ranged from 4.5 to 20%.

(2) Sex ratios in the collections varied significantly through time and …


Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon Apr 1981

Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon

Maine Collection

Maine's Whitewater Rapids and Their Relevance to the Critical Areas Program

by Janet McMahon

Planning Report No. 74, Critical Areas Program, 184 State St., Augusta, Maine,

April, 1981 (additions made in October, 1981). Reprinted July, 1983.

Contents: Introduction / Natural History of Whitewater Rapids / Methods / Criteria / Results / Conclusions / General Evaluation of Whitewater Rapids for Inclusion on the Register of Critical Areas / Bibliography / Action Plan


Mouthpart Morphology And Feeding Strategies Of The Commensal Amphipod, Anamixis Hanseni Stebbing, James Darwin Thomas, George W. Taylor Apr 1981

Mouthpart Morphology And Feeding Strategies Of The Commensal Amphipod, Anamixis Hanseni Stebbing, James Darwin Thomas, George W. Taylor

Marine & Environmental Sciences Faculty Articles

The lack of the information on the biology of the commensal amphipod family Anamixidae prompted investigations into mouthpart ultrastructure, feeding biology, and host specificity of Anamixis hanseni Stebbing, 1897. Earlier investigators presented conflicting reports on the structural composition of the buccal region and feeding modes in anamixids. Scanning electron microscope analysis of A. hanseni showed a complete set of mouthparts to be present, although much modified and reduced, except for the well-developed maxilliped palps. Feeding is not parasitic (piercing and sucking host tissue) as previously believed but is accomplished while A. hanseni rests inside its host. Minute food particles are …


Storm-Sewer Input Of Heavy Metals Into An Urban Lake Environment, George A. Duba Apr 1981

Storm-Sewer Input Of Heavy Metals Into An Urban Lake Environment, George A. Duba

Dissertations

The purpose of this study was to measure the concentration of lead, cadmium, zinc and copper in runoff entering an urban lake ecosystem and to measure the distribution of these metals in selected tropic levels of the lake.

Fisk Lake was chosen as the study site and is located in East Grand Rapids, Michigan. Samples were collected of stormwater, rainwater and lakewater together with substrate, aquatic macrophytes Peltandra virginica, chironomid larvae, Chironomidae, snails Physa, and eight species of fish, Ictalurus nebulosus, Esox lucius, Lepomis gibbosus, L. macrochirus, Pomoxis nigromaculatus, Micropterus salmoides, Catostomus commersoni, and Perca flavescens. All samples were collected …


High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan Apr 1981

High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan

Chemistry & Biochemistry Theses & Dissertations

The objectives of this research were to develop a sensitive method for separation and quantitation of biogenic amines and to apply that procedure by monitoring neurochemical changes resulting from stimuli to the test system.

Primary aromatic amines were derivatized with o-phthalaldehyde-mercaptoethanol prior to chromatography, Separation of the fluorescent adduct was achieved using a μBondapak/ phenyl reversed-phase column and a two-step gradient of methanol:0.08 M acetic acid, pH J.O. Fluorescence was monitored using a J40 nm excitation energy and an emission filter which transmits radiation greater than 400 nm (50% T at 418 nanometers).

Following optimization of the chromatographic conditions, studies …


Growth And Recruitment Of Two Penaeids In The Bay Of St. Louis, Mississippi During 1979, Teresa C. Heaton Apr 1981

Growth And Recruitment Of Two Penaeids In The Bay Of St. Louis, Mississippi During 1979, Teresa C. Heaton

OES Theses and Dissertations

Juvenile brown (Penaeus aztecus, Ives) and white (Penaeus setiferus, Linnaeus) shrimp were collected from two stations of a nursery area in St. Louis Bay Mississippi, during May to October, 1979. Periods of shrimp recruitment and growth were determined to discern whether the concurrent environmental variables of salinity and temperature had an influence on shrimp abundance and yield. Growth estimates were obtained from length frequency measurements of trawl samples taken over a 24-h period per month from each station. An analysis of variance of length versus the variables of sex, month, station, time of day, salinity and …


Seasonal Variations In Movements And Habitat Use By Pine And Meadow Voles, Ralph E. Pagano, Dale M. Madison Mar 1981

Seasonal Variations In Movements And Habitat Use By Pine And Meadow Voles, Ralph E. Pagano, Dale M. Madison

Eastern Pine and Meadow Vole Symposia

Free-ranging pine voles (Microtus pinetorum) and meadow voles (M. pennsylvanicus) were radio-tracked in a maintained apple orchard environment in August and December 1980. Meadow voles maintained larger home ranges than pine voles in the summer, but had similar-sized ranges in December. The home ranges for both species decreased with the onset of winter. Pine and meadow voles showed a strong tendency to remain within rows and to restrict most of their movement to areas beneath the canopy. Despite some overlap in space use between the species, the movements of both vole species suggested mutual avoidance. Differences …


Influence Of Apples On Population Density, Body Weights, And Reproductive Organ Weights In Pine Voles, J. J. Hasbrouck, F. A. Servello, A. R. Tipton, R. L. Kirkpatrick Mar 1981

Influence Of Apples On Population Density, Body Weights, And Reproductive Organ Weights In Pine Voles, J. J. Hasbrouck, F. A. Servello, A. R. Tipton, R. L. Kirkpatrick

Eastern Pine and Meadow Vole Symposia

Previous field studies at Virginia Tech have found differences in reproductive output of pine voles in abandoned and maintained orchards. Cengel et a1. (1978), trapping in northern Virginia, found higher levels of reproduction in a maintained orchard than in an abandoned orchard. The breeding season of voles extended into winter in the maintained orchard but ceased in late fall and winter in the abandoned orchard. Noffsinger (1976), working in orchards near Roanoke, Virginia, found a higher fatality rate in the maintained orchard and a year-round breeding season; however, the percentage of pregnant females declined in winter. Reproduction was lower in …


Spacing, Movements, And Social Organization Of A Free-Ranging Population Of Pine Voles Microtus Pinetorum, Randall W. Fitzgerald, Dale M. Madison Mar 1981

Spacing, Movements, And Social Organization Of A Free-Ranging Population Of Pine Voles Microtus Pinetorum, Randall W. Fitzgerald, Dale M. Madison

Eastern Pine and Meadow Vole Symposia

Free-ranging pine voles (Microtus pinetorum) were radio-tracked in a maintained orchard environment from August to November 1980. Pine voles existed in discrete non-overlapping family units with an average of 6.5 individuals per family unit. Home ranges of family members overlapped extensively, and all the members of a single family unit utilized one or two communal nest sites within the family's territory. Males ranged slightly farther than females, and females spent more time in the nest than did males. The mating system appeared to be promiscuous with a high degree of social tolerance among pregnant and lactating females and …


Digestibility And Nutritional Quality Of Apple Tree Roots And Other Orchard Forages Of The Pine Vole, F. A. Servello, R. L. Kirkpatrick, K. E. Webb Jr. Mar 1981

Digestibility And Nutritional Quality Of Apple Tree Roots And Other Orchard Forages Of The Pine Vole, F. A. Servello, R. L. Kirkpatrick, K. E. Webb Jr.

Eastern Pine and Meadow Vole Symposia

Analysis of the seasonal food habits of pine voles (Microtus pinetorum) by Cengel et a1. (1978) revealed that apple tree root consumption occurs only during winter months. Increased root consumption in the winter has been postulated to be due to a decrease in the quantity and quality of other foods in orchards. However, the normal translocation of carbohydrates into the root systems of trees during the dormant season may improve the quality of apple tree roots as a food source for voles. One objective of the pine vole nutrition studies at Virginia Polytechnic Institute and State University is …


Social Behavior Of The Pine Vole (Pitymys Pinetorum): I. Activity Patterns Of Mated Pine Voles In Semi-Natural Environments, Philip O. Renzullo, Milo E. Richmond Mar 1981

Social Behavior Of The Pine Vole (Pitymys Pinetorum): I. Activity Patterns Of Mated Pine Voles In Semi-Natural Environments, Philip O. Renzullo, Milo E. Richmond

Eastern Pine and Meadow Vole Symposia

The root damage resulting from pine vole (Pitymys pinetorum) infestation of apple orchards remains a major vertebrate pest problem. Currently, research effort is being directed at habitat management and at toxic bait development and application as two potentially cost-effective methods for control of these rodents. Recently, investigations have begun into the detailed relationships between the pine vole's physiology and it's habitat in an effort to understand and perhaps disrupt the seemingly ideal balance achieved by the animal in apple orchard situations. In addition to these approaches, which have possible immediate application, one area of pine vole biology that …


Analysis Of Seasonal Dynamics Of Pine Vole Populations In Two Virginia Orchards, S. B. Lindquist, A. R. Tipton, G. K. Yarrow, J. J. Hasbrouck Mar 1981

Analysis Of Seasonal Dynamics Of Pine Vole Populations In Two Virginia Orchards, S. B. Lindquist, A. R. Tipton, G. K. Yarrow, J. J. Hasbrouck

Eastern Pine and Meadow Vole Symposia

Presently, V. P. I. and S.U. is involved in a three year multi-disciplinary project to study pine and meadow vole ecology, behavior, and control (see additional V.P.I, and S. U. papers in Proc. Fifth East. Pine and Meadow Vole Symposium). In conjunction with this research, a long-term field study has been initiated to collect seasonal data on vole densities, survivorship, and reproduction in two Virginia apple orchards. The use of these data will be fourfold: (1) to gain insight into the dynamics of Virginia vole populations; (2) to act as a reference (or control) for future field experiments involving manipulation …


Social Context Affects Expression Of Conditioned Taste Aversions During Grooming By Pine Voles: Implications For Animal Damage Control, J. Russell Mason, Lynette A. Geyer, Christine A. Kornet Mar 1981

Social Context Affects Expression Of Conditioned Taste Aversions During Grooming By Pine Voles: Implications For Animal Damage Control, J. Russell Mason, Lynette A. Geyer, Christine A. Kornet

Eastern Pine and Meadow Vole Symposia

Rodents typically show conditioned aversions to substances previously associated with illness. Aversions can be observed when the tastant is presented in food, water and, for rats, when the tastant is smeared unilaterally on the animal's flank and ingested during auto-grooming. Such results have important implications for rodent control. For that reason, others have investigated whether voles and mice continue to groom when tastants associated with sickness are smeared on their fur. Investigations have shown that grooming persists in the presence of the conditioned stimuli even though strong aversions are shown toward the same tastants in a drinking context. The question …


Social Organizations And Reproduction In Freely Reproducing Colonies Of Pine Voles In The Laboratory, Margaret H. Schadler Mar 1981

Social Organizations And Reproduction In Freely Reproducing Colonies Of Pine Voles In The Laboratory, Margaret H. Schadler

Eastern Pine and Meadow Vole Symposia

Freely reproducing colonies of pine voles reared in confined laboratory enclosures have a definite social organization and a predictable pattern of reproduction which results in limitation of population size. Colonies that were established in the laboratory with a single breeding pair showed that: 1) populations were self-limiting, 2) rank order existed with the founding female occupying a dominant position in the hierarchy, 3) reproduction was generally confined to the founding female and 4) the non-reproducing members of the colony showed that they did become reproductive when they were paired with normal mates. This paper is a preliminary report of the …


A System For The Observation Of Voles Under Semi-Natural Conditions With Applications To: Social Interactions, Competition, Food Habits, Habitat Preference And Bait Accpetance., D. S. Wilkie, M. A. Novak Mar 1981

A System For The Observation Of Voles Under Semi-Natural Conditions With Applications To: Social Interactions, Competition, Food Habits, Habitat Preference And Bait Accpetance., D. S. Wilkie, M. A. Novak

Eastern Pine and Meadow Vole Symposia

A laboratory system to study microtine rodents has been developed that avoids many of the intrinsic restrictions of earlier laboratory and field studies. The system is composed of two interconnected plexiglas tables with a soil substrate and hay cover. The system permits unconstrained visual observation of voles as they move within a runway network of their own construction. The flexibility of the system facilitates its use in various avenues of microtine research.


Growth And Development Rates Of Microtus Pinetorum Under Different Photoperiods, T. L. Derting, J. A. Cransford Mar 1981

Growth And Development Rates Of Microtus Pinetorum Under Different Photoperiods, T. L. Derting, J. A. Cransford

Eastern Pine and Meadow Vole Symposia

Photo-period and nutrition are important variables affecting reproductive activity and growth in many rodents. Field and laboratory studies indicate that long photo-period (spring-summer) cause Increased growth while short photo-periods (fall-winter) inhibit these processes. In the montane vole (Microtus montanus) recently weaned animals gain weight at a much lower rate under short photo-periods or in total darkness than under long photo-periods (Vaughan et al., 1973; Peterborg, 1978). Adult M. montanus had more offspring and larger mean litter sizes under LD 18:6 than LD 6:18 (Pinter & Negus, 1965). Similarly, long (LD 16:8) or increasing photo-periods stimulated the onset of …


Frontmatter Mar 1981

Frontmatter

Eastern Pine and Meadow Vole Symposia

Frontmatter