Ecology and Evolutionary Biology Commons^™

Aspen Forest After Harvest, Norbert V. Debyle

Aspen Bibliography

Aspen is a unique forest tree with respect to regeneration. It produces abundant root suckers, up to 40,000 per acre are common, after clearcutting or fire removes the parent stand. The rapidly growing sucker stand competes well with other vegetation, but is susceptible to destruction by excessive ungulate browsing. Clearcut areas produce more streamflow and more growth on shrubs and herbaceous vegetation than does the uncut forest. The patchwork of age classes that results from even-age management optimizes wildlife habitat requirements for several desired species.

Effects Of Clear-Cutting On Nutrient Losses In Aspen Forests On Three Soil Types In Michigan, Curtis J. Richardson, Jeffrey A. Lund

Aspen Bibliography

The effects of clear-cutting on NO^-₃, NH⁺₄, PO^3-₄, K⁺, Ca²⁺, Na⁺, Fe²⁺, and Mg²⁺ losses were evaluated in three 60-year-old aspen stands in northern lower Michigan.

Odum's Ecosystem Attributes: Testing An Hypothesis, James A. Macmahon

Aspen Bibliography

No abstract provided.

Effect Of Salinity On Glycogen Content In The Brine Shrimp, Artemia Salinas, Of Great Salt Lake, Christon H. Merkley

Undergraduate Honors Capstone Projects

The brine shrimp, Artemia salinas, is one of the few organisms to be found in the hostile environment of the Great Salt Lake. Salt concentrations in the lake are found to exceed those in the oceans. In such an environment, the utilization of energy, even after it has been procured, presents a problem. The life inhabiting the lake has developed extraordinary adaptations to this and similar problems.

Electron micrographs produced by Dr. Nabil Youssef of Utah State University have revealed that unusual quantities of glycogen can be found in the muscle of brine shrimp taken from the Great Salt Lake. …

Forestry Report, P. Sims, G. Steneker, K. Fronting, C. Kirby, P. Van Eck, H. Johnson, N. Walker, R. Bohning, L. Carlson, I. Bella, W. Johnstone, R. Waldron, L. Brace

Aspen Bibliography

No abstract provided.

Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two intermediate wheatgrass seedings with different levels of grass bug infestation were evaluated for herbage production, seedhead production, percent dry matter, crude protein, and cell contents. Study sites were located at different elevations on mountain summer ranges in northern (Site I) and central (Site II) Utah. Study plots at Site I and Site II were infested with 113 and 210 bugs per sweep, respectively. Herbage production appeared to be reduced in early spring on the site with the higher infestation; however, no effect on season-long herbage production could be detected on either site. Seedhead production on infested plots was reduced …

Plant Light Responses Under Snow, Steven G. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several montane plant species and one alpine species were observed to grow under snow, and the seeds of 19 species germinated under snow. The spectral irradiance of light penetrating up to 198 cm of snow was measured with a device employing a photomultiplier tube and a series of interference filters. In deep snow, the measured peak in transmission was near 500 nm, but in older, more shallow snow the peak was at 550 nm. On two occasions measurements were made both before and after sunrise. There was a shift in the spectra toward the longer wavelengths as the sun rose …

Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Astragalus lentiginosus, which consists of 36 varieties, is one of the principal locoweeds of western North America. The objectives of this study included identification of some of the major factors affecting germination of the seed and survival of the newly established seedlings for several of these varieties.

The seeds of the varieties studied exhibited two mechanisms for dormancy. One is a seed coat that is impermeable to water, and the other is a water-leachable inhibitor. The presence or absence of low-intensity incandescent light (in 14-hour day lengths) had no effect on germination. Of three temperature regimes studied, the regime …

Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The framework of a stream ecosystem simulation model is described. Using this framework and data from two different geographical areas, a cold desert stream and a generalized mountain stream, exploratory sensitivity analysis was performed on the model. This was accomplished by qualitatively comparing outputs of a series of simulations in which a different level of a driving variable was used in each simulation. Based on these results, recommendations are made for improving the structure of the model.

Radial Distribution Of Corticular Photosynthate In Stems Of Bigtooth And Trembling Aspen, Robert K. Shepherd, Jr.

Aspen Bibliography

No abstract provided.

A Study Of The Radiation Quality Under Plant Canopies In The Wave Range 0.4 To 2.5 Microns, Nolasco G. Baldazo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spectral distribution of the global radiation from 0.4 to 2.5 microns penetrating deciduous and coniferous canopies were measured during clear days between 10 a.m. and 2 p.m. using a double-quartz monochromator.

In the visible region (0.4 to 0.7 micron) the average relative spectral transmissions under both canopies are about one percent beginning at 0.4 micron and decreasing to about half a percent at 0.67 micron. There is only a small peak in the green (0.55 micron) transmission under deciduous stands while there is none under coniferous canopies. The slightly higher transmission in the blue (0.4 micron) is attributed to …

The Dynamics Of Root Growth And The Partitioning Of Photosynthates In Cool Desert Shrubs, Osvaldo Alberto Fernandez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study addresses the nature of physiological and phenological evolutionary strategies of root growth dynamics and energy allocation followed by Atriplex confertifolia, Ceratoides lanata, and Artemisia tridentata growing in their natural cool desert environment.

Root observation chambers with inclined Plexiglass windows were installed in monospecific desert communities of Atriplex confertifolia, Ceratoides lanata and Artemisia tridentata. Soil temperature and water potential measurements taken immediately adjacent to the observation windows indicated a minimal disturbance was caused by the presence of these chambers. For the three species initiation of root growth was observed before initiation of shoot activity, furthermore, active root growth extended …

Location-Allocation Models For Establishing Facilities, David F. Gibson, John Rodenberg

Aspen Bibliography

Two models and accompanying computer programs are presented which were developed to locate facilities for the timber harvesting industry. Addressed is a case of the facility location-allocation problem. The optimum location and number of landings, facilities to which timber is transshipped, are determined so as to minimize a cost function. This function is composed of the following components: (1) cost of transporting material from its original location to a landing, (2) cost of establishing a landing (facility cost), and (3) cost of transporting material from the landings to some designated point termed the origin. Output of the computer programs is …

Short-Term Growth Response To Fertilization In Young Quaking Aspen, Keith Van Cleve

Aspen Bibliography

No abstract provided.

Continued Studies Of The Status, Socialization, And Relationships Of Isle Royale Wolves, 1967-1970., Michael L. Wolfe, Durward L. Allen

Aspen Bibliography

No abstract provided.

Community Characteristics Of Six Burned Aspen-Conifer Sites And Their Related Animal Use, Larry H. Kleinman

Aspen Bibliography

No abstract provided.

Effects Of Exercise On Serum Lactate Dehydrogenase Activity Of Catchable-Size Hatchery Rainbow Trout, Salmo Gairdneri, Gerlad T. Klar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Effects of exercise and the relative condition of exercised fish were viii evaluated for two strains of rainbow trout. Circular tanks fitted with a paddle were used to continuously exercise the fish and a stamina tunnel was used to evaluate the condition of exercised trout. Trout were exercised continuously at one fish-length per second and one-half fish length per second. Serum LDH activity in Shephard-of-the-Hills (Missouri) rainbow trout acclimated to 10 C increased two fold during the first four days of exercise. Serum LDH activity returned to control levels by the tenth day of exercise. Serum LDH activity in Shephard-of-the-Hills …

Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In seasons of above normal precipitation, populations of annual weedy species increase in great abundance in semi-arid desert plant communities. These increases in biomass tie up a considerable portion of the available nitrogen of such ecosystems and may depress subsequent annual grass germination.

A big sagebrush-annual bromegrass plant community was irrigated to simulate a spring growth period of abundant precipitation amenable to annual bromegras s productivity. Productivity and nitrogen content parameters were monitored throughout the spring and summer to evaluate the short and potential long term effects of this seasonal increase in "precipitation".

Irrigation increased annual bromegrass productivity almost 50 …

Internal Water Potential Of An Engelmann Spruce Stand In Relation To Soil And Atmospheric Factors, Richard L. Meyn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary objective of this study was to determine the degree of correlation between internal water potential of Engelmann spruce trees and selected environmental factors. The secondary objective of the study was to determine the effect of summer precipitation, both in meadow and forested sites, on the soil drying cycle.

Four study plots (each roughly 154 square meters) under spruce cover and two study plots (100 square meters) in a small meadow were established. At each spruce plot, a thermocouple psychrometer was installed at one meter above the ground on the north side of three selected, mature Engelmann spruce trees. …

Mechanisms Of Population Regulation In Confined Colonies Of Peromyscus Maniculatus (Wagner) And The Response To Exploitation, Donna Corn Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wild-trapped and laboratory-reared Peromyscus maniculatus (Wagner) were raised as confined colonies indoors with various stocking densities ranging from 0.026 to 0.100 mice per sq. ft. in pens of 40, 77, and 154 sq. ft. The animals were individually tagged and all pens were censused at weekly or semi-monthly intervals to record animals present, body weights, food consumption, and overt reproductive condition. At the termination of each experiment, all mice were necropsied and organ weights of gonads and adrenals recorded. Histological sections were made of the testes and ovaries. Half the colonies were subjected to density-independent exploitation by removal of 50% …

Annual Periodicity In A Free-Living Hibernator, The Uinta Ground Squirrel, Fred L. Knopf

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study documents the timing of seasonal events and associated changes in body weights of Uinta ground squirrels (Spermophilus armatus) that live at three different altitudes. The investigation provides detailed field data for biologists investigating circannual rhythms and hibernation in the laboratory.

Ground squirrels aroused and subsequently emerged from hibernation in an overlapping sequence: adult males first, followed by adult females, yearling females and yearling males. Within limits some climatic condition(s) delayed emergence and increased the overlap in emergence sequence. The duration of seasonal activities above ground averaged about 90 days for adult and yearling squirrels. Juveniles were …

Cottonwood Recovers From Deer Browsing, R. M. Krinard

Aspen Bibliography

No abstract provided.

Field Measurements Of Photosynthesis And Leaf Growth Rates Of Three Alpine Plant Species, Douglas A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaf photosynthetic measurements using a portable ¹⁴Co₂ field system were carried out and correlative leaf relative growth rates, RGR, were determined at different leaf positions of three alpine plant species throughout the growing season. Initially there was a period of high leaf RGR associated with a period of increasing photosynthetic activity. Following this stage was a long period of no net change in length of the living leaf. During this period, photosynthetic activity generally increased to a maximum level and then decreased steadily. The final ontogenetic stage was a period of negative leaf RGR denoting leaf senescence which …

Trout Movements In A Small Mountain Stream, Thomas Mark Twedt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Five groups of 400 hatchery rainbow trout, (Salmo gairdneri), were stocked in a small, mountain stream at 3-week intervals from June to September, 1972. A fish trap captured any fish moving out of a 500 m study section.

Fish began moving at high levels during the first day of each stocking and continued at high rates for 5-8 days (Early Phase), after which movement decreased to low levels for 6-9 days (Late Phase). Early Phase fish moved primarily at night, possibly due to their disoriented state and high subjectivity to stream conditions. Fish moving during Late Phase did …

Autecological Life History Studies Of Two Geraniums, Geranium Richardsonii And Geranium Nervosum, Becky Lee Green

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two perennial species of wild geranium (Geranium nervosum Rydb. and G. richardsonii Fisch, and Trautv, [Geraniaceae]) which grow throughout the mountainous regions of western North America were studied to determine the factors influencing the life stage development and distribution of these plants. Attempts were also made to provide some information to assist in the taxonomy of this genus.

Geranium richardsonii is found in wet meadows and along streambanks throughout its distribution. Geranium nervosum frequents rocky hillsides and drier meadows throughout its range.

Seeds of G. nervosum had 65%, germination in the stratification pretreatment. Geranium richardsonii seeds required scarification to …

Habitat Selection By Large Wild Ungulates And Some Aspects Of The Energy Flow In A Sub-Tropical African Savanna Woodland Ecosystem, Stanley M. Hirst

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study of habitat selection by large wild ungulates was carried out on a 50 cm² area in the sub-tropical Lowveld region of eastern Transvaal province, South Africa. Estimations were made of herbaceous forage net productivity and ungulate secondary productivity on the same area.

Fourteen vegetation types, varying in composition and structure from open savanna to dense woodland, were delineated by association analysis. Structural and vegetational characteristics which were considered to influence ungulate distribution were measured within each vegetation type.

The study area supported resident populations of seven ungulate species during the wet season; drv season densities were higher …

A Seed Demography Model For Finding Optimal Strategies For Desert Annuals, J. Curtis Wilcott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A theoretical investigation of the factors that affect the population dynamics of annual plants growing in deserts was conducted through the use of computer modeling techniques. A series of three models of the yearly life cycle of desert annuals was constructed and their behavior examined. The dissertation centers around the third and most complex model, a computer simulation model with distinguishable seed cohorts in a randomly varying rainfall environment. A typical simulation run was for 80 years and cost $1.00.

The five plant functions were (l} seed losses (mainly predation) as a function of seed age, (2) seed dormancy as …

Yields From 18-Year-Old Aspen Via Total Tree Harvesting, M. K. Benson, D. W. Einspahr

Aspen Bibliography

Described are the results of harvesting the above-ground parts of an 18-year-old aspen stand and the observations made on the initial suckering of the new stand. The yields for the stand of 17.7 cunits per acre were greater than predicted yields of comparable material for the site at age 35. Suckering on the area the first year after cutting averaged 37,000 aspen stands per acre and 2.6 feet in height.

Population Ecology Of Uinta Ground Squirrels, Norman A. Slade

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The behavior and ecology of Uinta ground squirrels (Spermophilus armatus) at the Utah State University Forestry Field Station northeast of Logan, Utah were studied from 1964-1971 to determine the role of behavior in population regulation. From 1965 to 1968, data were collected to establish population norms. In 1968, the population density was reduced experimentally to help elucidate regulatory processes. This paper compares the dynamics of the population before and after the population reduction.

Before the density reduction, juvenile survival was lower than that of yearlings and adults. The disappearance of juveniles was associated with their tendency to disperse …

Influence Of A Soil Microfloral Crust On Hydrologic And Chemical Properties Of Soils In Southeastern Utah, Walter L. Loope

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Cryptogamic soil crusts within the Colorado Plateau were studied to determine their effect on infiltration rates, potential sediment production, permeability, and several chemical properties of the soil. Six different crust stages were identified. Undisturbed soil cores were used to determine intrinsic permeability under three treatments and disturbed soil samples were analyzed for pH, percent organic matter, soil texture, Ca+Mg content and total conductivity.

It was found that the cryptogamic crust had little effect on soil chemical properties. Analysis of undisturbed soil core data indicates that high cryptogamic cover tends to decrease intrinsic permeability; this effect was reinforced when cores were …