Digital Commons Network^™

Modelling Age- And Density-Related Gas Exchange Of Picea Abies Canopies In The Fichtelgebirge, Germany, Eva Falge, John D. Tennhunen, Ronald J. Ryel, Martina Alsheimer, Barbara Köstner

Wildland Resources Faculty Publications

Differences in canopy exchange of water and carbon dioxide that occur due to changes in tree structure and density in montane Norway spruce stands of Central Germany were analyzed with a three dimensional microclimate and gas exchange model STANDFLUX. The model was used to calculate forest radiation absorption, the net photosynthesis and transpiration of single trees, and gas exchange of tree canopies. Model parameterizations were derived for six stands of Picea abies (L.) Karst. differing in age from 40 to 140 years and in density from 1680 to 320 trees per hectare. Parameterization included information on leaf area distribution from …

Fate And Behavior Of Lead In Soils Planted With Metal-Resistant Species (River Birch And Smallwing Sedge), S. P. Klassen, J. E. Mclean, P. R. Grossl, Ronald C. Sims

Biological Engineering Faculty Publications

Phytoremediation of metal-contaminated soils requires an understanding of the interactions between metal-tolerant plant species and soil chemical properties controlling the bioavailability of metals. We conducted controlled laboratory studies to investigate the effects that river birch (Betula occidentalis Hook.) and smallwing sedge (Carex microptera Mack.) had on the fate and behavior of Pb in a contaminated soil (3000 mg Pb/kg) and tailings (13 000 mg Pb/kg) collected from an abandoned mining site in Utah. Significant Pb accumulation in aboveground tissue was observed in smallwing sedge (≥1000 mg/kg dry wt.) in both the soil and tailings, but Pb was primarily excluded by …

Direct And Indirect Effects Of Herbivores On Nitrogen Dynamics: Voles In Riparian Areas, J M. Sirotnak, Nancy J. Huntly

Biology Faculty Publications

Herbivores can directly increase nitrogen mobility by increasing the quality of organic matter entering the decomposition cycle, but they also may decrease nitrogen mobility by decreasing the biomass of high-nitrogen species in the plant community. We assessed effects of voles (Microtus) on nitrogen dynamics using exclosures in two riparian meadows (Crystal Bench and Blacktail Deer Creek) in Yellowstone National Park (USA). At both sites, the quantity of plant litter was decreased by herbivory following a vole population peak in 1992. At Crystal Bench, removal of voles caused a decrease in the nitrogen concentration and an increase in the C:N ratio …

Organic Carbon Supply And Metabolism In A Near-Stream Groundwater Ecosystem, H. M. Valett, C. C. Dahm, Michelle A. Baker

Biology Faculty Publications

In groundwater ecosystems, in situ primary production is low, and metabolism depends on organic matter inputs from other regions of the catchment. Heterotrophic metabolism and biogeochemistry in the floodplain groundwater of a headwater catchment (Rio Calaveras, New Mexico, USA) were examined to address the following questions: (1) How do groundwater metabolism and biogeochemistry vary spatially and temporally? (2) What factors influence groundwater metabolism? (3) What is the energy source for groundwater metabolism?

At Rio Calaveras, surface discharge and water table elevation increased at the onset of spring snowmelt. Groundwater biogeochemical changes in response to snowmelt included increases in dissolved oxygen …

Proper Use Of Ammoniated Low-Quality Forages For The Wintering Of Spring-Calving Beef Cow Herds In The Intermountain West, D. R. Zobell

All Current Publications

Low‐quality forages (LQF) such as cereal straws or post‐ripe hays are often used as economical feed sources for the wintering of beef cow herds. The ammoniation of such forages increases the digestibility and crude protein (CP) enough so that these forages can be used as the basis of beef cow diets, even during late gestation and early lactation if supplemented properly.

Saltcedar, Tamarisk, Ruth Richards, Ralph Whitesides

All Current Publications

Saltcedar is diffi cult to control. Single treatment approaches to control saltcedar have not proven feasible because no method completely eliminates saltcedar or its regeneration.

Saving Utah's Landscape, Squarrose Knapweed, Usu Extension

All Current Publications

What began in the 1950s as a small patch of weeds near a grain elevator in Juab County, turned into a serious environmental problem that impacts the state’s wildlife, grazing and tourist industries. In the early 1990s, it was estimated that squarrose knapweed infested nearly 200,000 acres of rangeland in central Utah.

Sustainable Orchard Management System, Diane Alston

All Current Publications

Fruit production in the intermountain west is besieged with problems. To cope with these problems, fruit growers mustbe competent in financing, banking, buying, public relations, marketing, meteorology, climatology, plant science, soil science, entomology, pathology, irrigation, fertilization, chemistry, physics, mechanics, and management.

Mammal Research In Southern Africa: Present Patterns And Future Priorities, Johan T. Du Toit, L. S. Broomhall

Wildland Resources Faculty Publications

We conducted a survey to identify present patterns and future priorities for mammal research in southern Africa (countries including and southwards of Angola, Zambia and Tanzania). Two sets of peer-reviewed journals were scanned for papers on southern African mammal research over the period 1988-1998: one set comprised five journals published in South Africa; the other comprised 10 journals published abroad. For the same period we reviewed titles of M.Sc. and Ph.D. dissertations completed in zoology departments of South African universities. A questionaire was administered by e-mail to. 126 researchers active in mammal research in southern Africa, concurrently with a separate …

Environmental Assessment, Decision Record, And Finding Of No Significant Impact For The Ixc Communications, Inc.'S Proposed Fiber Optic Telecommunications System, Denver, Colorado, To Salt Lake City, Utah, U.S. Department Of The Interior, Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

IXC proposes to install and operate a telecommunications system from Denver, Colorado, to Salt Lake City, Utah, to provide service to these and other western cities. The approximately 611-mile long cable would cross 116 miles of federal land administered by the BLM (all within Wyoming), 1 mile of National Forest lands administered by the Forest Service (all within Utah), and 494 miles of state, county, municipal, and private lands. Three 1.9-inch and three 2.4-inch high-density polyethylene conduits would be installed simultaneously and a fiber optic cable would be installed in one conduit; the other conduits would be used for future …

Water Resources Systems Analysis - Course Notes, A Bruce Bishop, Trevor Hughes, Mac Mckee

All ECSTATIC Materials

Water resources systems analysis course notes for CEE 6410 taught at Utah State University. Coverage includes:

Chapter 1 - Concepts and methods

Chapter 2 - Linear programming-introduction and graphical methods

Chapter 3 - Linear programming - simplex method

Chapter 4 - Linear programming - applications to simple water problems

Chapter 5 - Dual LP and post optimality analysis

Chapter 6 - Integer programming

Chapter 7 - More applications of integer programmign

Chapter 8 - Piecewise linearization

Chapter 9 - Other types of LP models

Chapter 10 - Dynamic programming

Chapter 11 - Gradient-based nonlinear optimization methods

Chapter 12 - Genetic …

Marginalia No. 7, Merrill-Cazier Library

Marginalia

Issue Number 7: the proverb issue Autumn 1999

A MESSAGE FROM DEAN WHITE - new Dean of Libraries introduces herself.

“BIG THINGS COME IN SMALL PACKAGES”-Randy Williams on Proverbs, Power and Books.

INSTRUCTION: ‘IT TAKES SHARP WITS…’-Listing of Reference Librarians & Library instruction services

MERRILL LIBRARY RENOVATIONS-A brief discussion of recent changes in the Merrill Library

THE ART OF LARRY ELSNER-Art curator Rose Milovich on the upcoming exhibit and silent auction fund-raiser

USU LIBRARIES EXHIBITION SCHEDULE, 1999-Upcoming exhibits in the Library Gallery

THE STANFORD O. CAZIER SCITECH LIBRARY-Director Max Peterson reports

UTAH ACADEMIC LIBRARY CONSORTIUM- Assoc. Director, Robert Murdoch describes …

Final Intrinsic Remediation, Engineering Evaluation/Cost Analysis Addendum For Ust Site 870, Hill Air Force Base, Ogden, Utah, Parsons Engineering Science, Inc.

All U.S. Government Documents (Utah Regional Depository)

This report was prepared for the Air Force Center for Environmental Excellence (AFCEE) by Parsons Engineering Science, Inc. (parsons ES) as an update to the Final Intrinsic Remediation Engineering Evaluation/Cost Analysis (EE/CA) for Underground Storage Tank (UST) Site 870, Hill Air Force Base (AFB), Utah (parsons ES, 1995). The EE/CA was conducted to evaluate the use of intrinsic remediation with long-term monitoring (LTM) for remediation of fuel hydrocarbon contamination dissolved in groundwater at UST Site 870. This update summarizes the results of the third sampling event performed as part of longterm groundwater monitoring at the site. This sampling was conducted …

Comparison Of A Genetic Algorithm And Mathematical Programming To The Design Of Groundwater Cleanup Systems, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We present and apply a new simulation/optimization approach for single- and multiple-planning period problems in groundwater remediation. Instead of the traditional control locations for contaminant concentrations, we use an L_QC norm as a global measure of aquifer contamination (CMAX). We use response-surface constraints to represent CMAX within the optimization model. We compare the performance of formal mixed integer nonlinear programming and a genetic algorithm for several optimization scenarios.

Optimal Design Of Aquifer Clean Up Systems Under Uncertainty Using A Neural Network And A Genetic Algorithm, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We present a methodology to account for the stochastic nature of hydraulic conductivity during the design of pump-and-treat systems for aquifer cleanup. The methodology (1) uses a genetic algorithm to find the global optimal solution and (2) incorporates a neural network to model the response surface within the genetic algorithm. We apply the methodology for a real example and different optimization scenarios. The employed optimization formulation requires few hydraulic conductivity realizations. The presented approach produces a trade-off curve between reliability and treatment facility size .

Synecology And Disturbance Regimes Of Sagebrush Steppe Ecosystems, Neil E. West

Wildland Resources Faculty Publications

The pre-Columbian mixed-growth form, composition, and structure of sagebrush steppes was mostly due to the highly variable semiarid climate and long fire-free intervals. The weak stability of this relatively complex vegetation was easily upset by excessive livestock grazing, especially in drought periods. After a few decades of uncontrolled livestock grazing, it was easy for introduced winter annuals, especially cheatgrass, to dominate the understory and alter the fire regime to larger, more frequent fires that occur earlier in the year. Accelerated soil erosion has caused many sites to lose the potential for management back toward native perennial dominance by controlling only …

Spacecraft Formation Flying Via Dynamic Compensation, Jonathan Lawton, Randal W. Beard, Fred Y. Hadaegh

Utah Space Grant Consortium

In this paper we present a passivity based control for spacecraft formation flying. We derive both attitude and position control. The controls do not require velocity information. They only require information about the position and attitude of the given robot and two of its neighbors. Furthermore, our approach has the advantage that we provide convergence results and establish bounds on the formation error.

The Deseret Ranch: An Environmental History, Shawna Morrissey

Utah Space Grant Consortium

This paper outlines the project I am undertaking for my thesis. My thesis will examine the ecological history of the Deseret Land and Livestock Ranch. It will integrate quantitative and qualitative data to interpret a century of environmental change. While my research focuses on the period from 1891 to the present, it will also briefly review the long-term natural history of the region. This thesis will provide an opportunity to integrate traditional historical sources with new technologies. I will apply Geographic Information Systems (GIS) and Remote Sensing technology to graphically chart environmental change. These innovative historical sources, in addition to …

Utah State University Commencement, 1999 - Eastern Campus, Utah State University

Commencement Programs

1999 Commencement Ceremony for the Eastern Campus of Utah State University.

Insights, Spring, 1999, Utah State University

Discovery Magazine

Bi-annual alumni newsletter for the College of Science of Utah State University in Logan.

Isolation, Cloning, And Identification Of Syringomycin E Action Genes Of Saccharomyces Cerevisiae, Stephen D. Stock

Biology

Members of the syringomycin family of antifungal cyclic lipodepsipeptides are produced by Pseudomonas syringae pv. syringae strains as secondary metabolites. These metabolites are potent antifungal agents effective against a broad range of fungi. The antifungal mechanism of action of these compounds has been investigated using syringomycin E and Saccharomyces cerevisiae as a model fungal system. Mutants resistant to the growth inhibitory effects of syringomycin E were isolated after mutagenesis with nitrosoguanidine. These mutants were screened for the production of ergosterol and by complementation with syr2 mutants to eliminate mutants belonging to known syringomycin E-resistant complementation groups. From a total of …

Estimating Total Body Fat In Sharp-Shinned And Cooper's Hawks: Techniques And Application, John P. Delong

Biology

I evaluated the use of three direct methods (fat scoring, condition indices, and multiple regression of external morphological variables) and one indirect method to estimate total body fat (TBF) in Sharp-shinned Hawks (Accipiter striatus) and Cooper's Hawks (A. cooperii). All three direct methods explained a reasonable amount of variation in actual TBF values (r² ≥ 0.82), and all three methods required the use of four equations to account for the categories of species, age, and sex. Indirect methods are those that predict lean mass and subtract the lean mass estimate from the actual body …

Rubisco Deactivation: The Effects Of Growth-Light Conditions And Effects Of Co2 During Shade Events, Jerriann Ernstsen

Biology

Rubisco's (ribulose 1,5-bisphosphate carboxylase/oxygenase) catalytic activity changes as light intensity changes. This study addresses factors that were expected to affect Rubisco deactivation during low light. First, effects of fluctuating light and constant sun or shade during plant growth on Rubisco deactivation and activation were evaluated for basil (Ocimum basilicum and impatiens (Impatiens wallerana). Rubisco activation rate and the degree of Rubisco deactivation were determined from gas-exchange measurements of photosynthesis following a step increase in light intensity. Rubisco activation state during low light was also determined from biochemical analyses of leaf extracts. There were no significant differences in …

Characteristics Of Bald Eagle Communal Roosts In Northern Utah And A Survey Of Eagles Occupying Roosts, Robert B. Wilson

Biology

The numbers of eagles occupying either the Willard Canyon roost or the Ogden Bay roost exceeded the combined total of other communal roosts documented in Utah. These roosts are among the largest known communal roosts in the lower 48 states, and the largest documented winter roosts within the McKenzie-Intermountain Flyway. During the winters of 1997-98 and 1998-99 I surveyed several Bald Eagle (Haliaeetus leucocephalus) roost sites in northern Utah to document their geographic location, habitat, and occupancy. I conducted surveys from December 1997 to April 1998 and December 1998 to April 1999. Most winter roosts were communal, as …

Implications Of Stomatal Interactions, Thomas Norman Buckley

Biology

Though stomatal apertures often vary randomly within a leaf, suggesting somata behave independently, recent evidence suggests stomata may interact. In the phenomenon of patchy stomatal conductance, stomatal behavior becomes coordinated at the intermediate scale of one or more areoles but discoordinated at larger scales. This has two general implications. First, it makes relationships between certain gas exchange properties highly scale dependent, affecting the interpretation of large-scale measurements in terms of small-scale properties and the upscaling of models based on small-scale mechanisms. Second, it indicates some yet-unidentified mechanism for stomatal interactions. A model of gas exchange in a leaf with heterogeneous …

The Roles Of Superoxide Dismutases Of A Plant-Beneficial Bacterium, Pseudomonas Putida, And A Phytopathogenic Bacterium, Pseudomonas Syringae Pv. Syringae B728a, During Plant Colonization, Young Cheol Kim

Biology

Both Pseudomonas putida and Pseudomonas syringae produced manganese-superoxide dismutase (MnSOD) and iron-superoxide dismutase (FeSOD). Genes sodB, encoding FeSOD, and sodA, encoding MnSOD, were cloned. The sodB genes were transcribed as monocistronic transcripts, expressed throughout growth phases when iron was available. The sodA genes were part of polycistronic operons, and transcripts of the operons were induced only in iron-deficient conditions. The effect of mutations in the SOD genes was observed during root colonization by Pseudomonas putida. The sodB and sodAsodB mutants were impaired in root colonization in mixed inoculations with wild-type. Growth of the sodB and sodAsodB mutants …

Roles Of Plasma Membrane Lipids In Syringomycin E Action In Saccharomyces Cerevisiae, Rungrach Wangspa

Biology

The bacterium Pseudomonas syringae pv. syringae produces an antifungal secondary metabolite, syringomycin E. Yeast growth inhibition by this lipodepsipeptide involves sterol and sphingolipids of the plasma membrane. Using a sterol auxotroph of Saccharomyces cerevisiae, strain FY-14, it was shown that the predominant sterol in yeast, ergosterol, is not required for the mechanism of action of this metabolite. With ergosterol, cholesterol, β-sitosterol or stigmasterol as the bulk sterol, strain FY-14 was sensitive to syringomycin E with the last two conferring the highest degree of sensitivity. The type of growth-promoting sterol influenced cellular sensitivity to syringomycin E. Growth-promoting ergosterol afforded the …

Interaction Between Winter Dominance And Territory Defense In Male Pronghorn Antelope, Antilocapra Americana, Charles William Gunnels Iv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In a territorial population of pronghorn from Antelope Island, UT, interaction between male dominance and territory defense was examined. High-ranking males were more likely to defend territories. Closely ranked animals engaged in more dominance interactions than distantly ranked individuals, and middle-ranked animals were involved in disproportionately more interactions than either high- or low-ranking animals. Large males possessed large horns and prongs as well as small cheek patches. Results from a factor analysis suggested that large males defended territories with a high density of sage. However, in this study, we did not observe pronghorn feed on sage during the territorial season. …

Multi-Scalar Spatial Modeling Of Northern Forest Dynamics: Foundations, Theories, And Applications, Don C. Bragg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation describes the development and analysis of a new forest dynamics model. The NORTHern Woodland Dynamics Simulator (NORTHWDS) was designed to spatially model forest pattern and process for the northern Lake States, and to incorporate multiple spatial scales. While ecologically detailed, this stand table-based model is sufficiently parsimonious to be able to simulate 100s to 1000s of hectares for centuries. Processes like tree regeneration, growth, and mortality, herbaceous and shrubby competition, biogeochemistry, carbon cycling, edge effects, and climatic influences are incorporated in NORTHWDS. Wind disturbance and white-tailed deer browsing were also included …

Latin American Immigrants' Perceptions Of Discrimination And Acquisition Of English As A Second Language As A Result Of Using A Community Social Support Center, Holly Mcfarland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The associations between Latin American immigrants' use of a community social support center and perceived discrimination and language acquisition were investigated. All variables were measured by respondents' self-reports on a questionnaire designed to obtain demographic data as well as describe the needs of the Latin American community in rural Northern Utah. Chi-square analyses indicated a statistically significant association between use of the center and acquisition of English as a second language. No relationship was found between use of the center and perceived discrimination. The results of this study provide valuable demographic data as well as describe some of the experiences …