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The Study Of Activated Sludge Settleability Using The Solids-Flux Analysis, Churng-Cherng Lin

Theses

The activated sludge was cultivated in two pilot-scale activated sludge systems under three ratios of BOD to N, equal to 20:1, 70:1 and 300:1 in the influent wastewater. The aeration tank of the activated sludge system was constructed in two different configurations: one without compartments in the tank, the other consisting of six compartments. The activated sludge withdrawn from the last compartment of each system was tested in a one-liter graduate cylinder to measure its zone settling velocity. The solids-flux method was employed to analyze the sludge settling characteristic as a function of solids concentration. The results show that the …

Interactions Between Populations Of Intermediate Wheatgrass And Western Wheatgrass As Influenced By Short-Duration Grazing And Moisture Availability, Gerrit B. Bartels

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of grazing and moisture availability on the competitive interactions of intermediate wheatgrass (Thinopyrum intermedium (Host) Barkw. & D.R. Dewey) and western wheatgrass (Pascopyrum smithii (Rhydb.) A. Love) were examined under a short-duration grazing system in central Utah. The fate of tiller cohorts was observed at approximately monthly intervals at the interface between patches of these two rhizomatous grasses and in monospecific stands. The effects of short-duration grazing, clipping of western wheatgrass following grazing to achieve levels of utilization equivalent to that of intermediate wheatgrass, irrigation, and removal of the competitor were assessed in terms of the …

Ecological Implications Of Flavor Generalization By Sheep: Role Of Flavor Intensity And Variation In Toxin Dose, Karen L. Launchbaugh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Researchers studying diet selection of ungulate herbivores have generally considered plant palatability independent of animals' dietary history. However, more recent studies demonstrate that experiences within the life of an animal strongly influence plant selection. We are beginning to understand how food preferences and aversions are formed through gastro-intestinal feedback. My research specifically examines factors that influence the formation of conditioned flavor aversions in the generalist herbivore, sheep.

I first examined how variability of food toxicity affects the intake of those foods. I determined that sheep apparently have several mechanisms for regulating intake of toxic foods regardless of whether or not …

Environmental Factors Influencing Prehistoric Site Selection Along The Portage River, A Tributary Of The St. Joseph River, Southwest Michigan, Timothy D. Knapp

Masters Theses

This study examines the environmental factors influencing the location of prehistoric sites within the Portage River drainage. Over 100 sites recorded during four seasons of archaeological survey are examined applying the following environmental variables: type of glacial deposit, glacial landform, soil, distance to the nearest source of water, distance to the nearest ponded water, and vegetation zones occurring within 100, 500, and 1000 meters. Site locations are then statistically compared with the location of 100 randomly generated loci within the study area.

The findings of this research indicate that sites are non-randomly located with respect to certain environmental variables. Sites …

A Handbook Of Environmental Science Activities For Pickaway County Secondary Science Teachers, Tammy L. Rosser

Graduate Theses and Dissertations

No abstract provided.

Influences On The Instream Distribution Of Astyanax Fasciatus In A Small River In Costa Rica., Cecil Kelly Swing

LSU Historical Dissertations and Theses

The instream distribution of the tetra, Astyanax fasciatus, was investigated through approximately 700 hours of field observations in a small Costa Rican stream on the southwestern Pacific coast near Golfito. Individuals tended to remain in particular pools where they subsisted primarily on a diet of terrestrial insects. These fish were able to migrate, and only as many individuals stayed in any pool as could be sustained there by available food resources. Because the water intercepted insects fairly uniformly over its surface, the biomass of fish occupying any particular pool was proportional to its surface area (r$\sp2$ = 0.652). The amount …

Population Status And Characteristics Of Macrhybopsis Gelida, Platygobio Gracilis And Rhinichthys Cataractae In The Missouri River Basin, Selena J. Werdon

Electronic Theses and Dissertations

Few sturgeon chub (Macrhybopsis gelida: Cyprinidae) have been collected in the last decade, therefore their status, habitat selection and morphology were investigated at 172 previous collection sites. Data on two ecologically similar species, Platygobio gracilis and Rhinichthys cataractae, were also collected. Macrhvbopsis gelida were collected at 28 sites on the Powder River (n = 158) in Wyoming and Montana, and at one site on the Yellowstone River (n = 1) in Montana. Age-I, Age-II and Age-III M. gelida were collected. Specimens were 37 to 95 mm in total length. Macrhvbopsis gelida were ripe in mid-June, at water temperatures of 18.3-22. …

An Ecological Study Of The Cumberland Plateau Salamander, Plethodon Kentucki Mittleman, In West Virginia, Jeffrey E. Bailey

Theses, Dissertations and Capstones

A study was conducted to determine various aspects of the ecology of Plethodon kentucki in West Virginia. Results of studies on range and distribution revealed that P. kentucki is limited to southwestern counties in West Virginia. A population of P. kentucki at Beech Fork State Park was extremely seasonal with regard to activity. Seasonal activity was not significantly correlated with air temperature, soil temperature, air relative humidity, or soil pH. Seasonal activity was significantly correlated with soil moisture. Critical Thermal Maxima and dehydration values were not significantly different between f· kentucki and its congener, P. glutinosus, thus each is equally …

Host Quality Of Baldcypress And Its Influence On Fruittree Leafroller, Archips Argyrospila (Walker) (Lepidoptera: Tortricidae), Performance In Forested Wetlands Of Louisiana., James R. Meeker

LSU Historical Dissertations and Theses

Ecological relationships between the fruittree leafroller (FTLR), (Archips argyrospila (Walker)) and a new host, baldcypress (Taxodium distichum (L.)), were investigated in southern Louisiana where persistent annual defoliation over increasingly larger areas has occurred since 1983. Defoliation was observed to correspond with common types of baldcypress foliage morphology; designated as open and appressed. Pondcypress, Shumard oak and citrus foliage also were examined. The objectives were to: (1) determine the relative suitability/susceptibility of foliage types, and (2) quantify parameters of foliage quality possibly influencing FTLR performance. Levels of defoliation, egg mass counts, and laboratory bioassays of: initial survival, host preference, growth, feeding, …

Ecosystem Models Of Aquatic Primary Production And Fish Migration In Laguna De Terminos, Mexico., Enrique Reyes

LSU Historical Dissertations and Theses

Laguna de Terminos is Mexico's largest coastal lagoon. There is a high habitat diversity including open water, mangroves, seagrasses and marshes, which supports Mexico's most economically important fisheries. Understanding ecosystem processes is essential for effective management of the lagoon's resources. This research developed landscape-level models for aquatic primary production (LAPPTER model), and fish migration (ROE model) in Laguna de Terminos. The ROE model was developed first as a theoretical approach, and later integrated into the LAPPTER model as a submodule which utilizes simulated production as a food source. The ROE model includes behavioral rules for fish movement based on environmental …

Developing A Guidebook For An Outdoor Classroom, David D. Martell

Theses Digitization Project

Field guide -- Map -- Nature trail plant species -- Plant identification key -- Species test plot -- Climate -- Cloud identification -- Desert soils -- Tortoise station -- Animal track and pond.

Mountain Habitat Activity Guide, Gina Glock

Theses Digitization Project

No abstract provided.

Student Perceptions Of The Transition From Year 10 To Year 11, Tim Mcdonald

Theses : Honours

Issues associated with the transition from Year 10 to Year 11 have largely been ignored by researchers. Previous research has predominantly focussed on the primary to secondary transition experience. The existing problem of lower school to upper school transition has been compounded by the increased importance of upper school and the rising retention rates. This study investigated student perceptions of the transition from Year 10 to Year 11. It explored student concerns encountered in the transition and the differences they perceived between Year 10 and Year 11 after having entered Year 11. A case study approach, incorporating both qualitative and …

Demography Of Sapphire Rockcress (Arabis Fecunda Rollins : Brassicaceae) A Rare Endemic Montana Species, Roberta Walsh

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Arbor Day Curriculum Unit For Grades Kindergarten Through Grade Six, Kathleen Ann Story

Theses Digitization Project

No abstract provided.

The First Documentation Of A Lower Middle Pennsylvanian Upland Flora From The Eastern Margin Of The Eastern Interior Basin (Illinois Basin), Vicki J. Comer

Masters Theses

The primary objective of this study is to reconstruct the paleofloristics of an unnamed shale of lower Middle Pennsylvanian age. The shale is periodically exposed in the highwall of the Ashboro Pit, Log Cabin Coal Company, Clay County, Indiana. This will be the first upland fossil flora to be described from the eastern margin of the Eastern Interior Basin (Illinois Basin). The gray shale containing the upland flora lies directly above the Upper Block Coal (SW 1/4, SE 1/4, sec. 17, T. 11N., R. 6W.)

Two collections, collected on three different occasions were made available for analysis: Smithsonian Natural …

Sussex School Backyard Nature Area Project, Yukiko Maeda Tanaka

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.