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A Geographic Information System Assessment Method For Fire Management: Identifying Fire Danger Areas, Richard D. Stratton May 1998

A Geographic Information System Assessment Method For Fire Management: Identifying Fire Danger Areas, Richard D. Stratton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In partnership with the USDA Forest Service and the Utah Division of Forestry, Fire, and State Lands, a geographic information system (GIS) was used to create a wildland fire assessment methodology. GIS layers (or themes) include topography, infrastructure, vegetation, climate, "sensitive" natural values, and fire history. Two phases of assessment are presented: a preliminary analysis designed for planning use at the landscape level, and a detailed analysis for site-specific use.

Results of the phase 1 assessment are density grids delineating areas of high fire occurrence and suggesting to managers where a phase 2 assessment is needed. By using the environmental, …


Attitudes And Roles Of Women And Minorities In Community And Urban Forestry Professions, Hope A. Bragg May 1998

Attitudes And Roles Of Women And Minorities In Community And Urban Forestry Professions, Hope A. Bragg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Community and urban forestry is a multifaceted field ranging from tree planting to removal, hazard assessment, and public relations. However, the racial and gender diversity of the community forestry workforce is remarkably low. To gain a better understanding of this lack of diversity, I surveyed professionals in two major community/urban forestry organizations. Age, income, and years in the profession were considered, along with education level, to determine if there is some underlying reason for low representation of women and minorities in the community/urban forestry field. I found that while white males dominated all work sectors (especially private organizations), women were …


Development And Validation Of Forest Habitat Models In The Uinta Mountains, Utah, Tracey S. Frescino May 1998

Development And Validation Of Forest Habitat Models In The Uinta Mountains, Utah, Tracey S. Frescino

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A significant question currently facing environmental managers is how to accurately and efficiently quantify forest diversity and resources. Numerous studies have demonstrated the use of modern spatial analytical tools, such as geographical information systems (GIS), remote sensing devices, and statistical models for predicting the distribution of dominant vegetation cover types. This study examines the ability of generalized additive models (GAMs) to delineate structural diversity in forested ecosystems (specifically the Uinta Mountain Range in Utah) using GIS tools and satellite spectral data, and analyzes the effect of including different forms of satellite data in model construction (i.e., Landsat thematic mapper (TM), …


Relationship Between Teton Science School Programs And Teachers' Ability To Teach About The Environment, Jennifer A. Levy May 1998

Relationship Between Teton Science School Programs And Teachers' Ability To Teach About The Environment, Jennifer A. Levy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents an analysis of 1996/97 survey research data regarding the relationship between three types of Teton Science School (TSS) programs and classroom teachers ' ability to teach about the environment. Based on observations by resident instructors and faculty at TSS, three research questions were developed. The primary objective of the research questions was to consider the relationship between TSS residential education programs and participating teachers' ability to teach about the environment.

Analyses are based on comparing descriptive statistics of teachers who have participated in one of the three types of TSS programs or a combination of the three …


Seed Dispersal By Livestock: A Revegetation Application For Improving Degraded Rangelands, Ferhat Gokbulak May 1998

Seed Dispersal By Livestock: A Revegetation Application For Improving Degraded Rangelands, Ferhat Gokbulak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of experiments was conducted to: 1) investigate how feeding cattle with different amounts of different-sized seeds affects seed passage rate through the digestive tract, and the germinability of passed seeds; 2) examine how the location of seeds in dungpats of different thicknesses influences seedling emergence, development, and survival in cattle dungpats; and 3) characterize seedling emergence in naturally and artificially deposited cattle dungpats. Three perennial, cool-season grasses, bluebunch wheatgrass [Psuedoroegneria spicata (Pursh) A. Love], Sandberg bluegrass (Poa secunda Presl.), and 'Hycrest' crested wheatgrass [Agropyron desertorum (Fisch. ex Link) X A. cristatum (L.) Gaert.], were used …


Water Uptake, Water Relations, Tree Growth, And Root Distribution Under Herbaceous Competition, Bertha Alicia Hernandez-Leos May 1998

Water Uptake, Water Relations, Tree Growth, And Root Distribution Under Herbaceous Competition, Bertha Alicia Hernandez-Leos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are numerous situations where trees are grown together with herbaceous plants. In these situations there will be some degree of competition between their root zones, depending on the water content of the soils and crop and tree root distribution. Two studies were conducted: the first with maple (Acer platanoides) grown in turf grass, and the second with willow (Salix matsudana) grown in more deeply rooted barley. The objectives of this study were to quantify the effect of herbaceous competition of potential tree water stress under irrigation and when the soil is allowed to dry-down. Soil …


Perceived Fairness And Effectiveness Of Rangeland Collaborative Processes, Kimberly J. Richardson May 1998

Perceived Fairness And Effectiveness Of Rangeland Collaborative Processes, Kimberly J. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Involvement in collaborative partnerships in natural resource management has become a popular method for natural resource management agencies to collect public input, cope with conflicts, and develop ecosystem management plans. This thesis evaluates various collaborative processes, emphasizing multiple-owner partnerships. Qualitative interviews of 46 landowners in Utah were conducted to reveal concerns and suggestions regarding multiple-owner landscape-level collaborative partnerships. Landowners were concerned about private property rights infringement and losing control of their private land. Landowners were primarily concerned about the fairness and effectiveness of any partnership in which they were involved.

However, they were willing to consider participating if certain procedural …


Effects Of Uv-B Radiation On Egg And Larval Golden Shiner (Notemigonus Crysoleucas) In Castle Lake, California, Jai-Ku Kim May 1998

Effects Of Uv-B Radiation On Egg And Larval Golden Shiner (Notemigonus Crysoleucas) In Castle Lake, California, Jai-Ku Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied effects of UV-B radiation on egg and larval golden shiner (Notemigonus crysoleucas) in Castle Lake, California, USA. To compare egg hatching and survival of larval golden shiner, I exposed eggs and larval fish to three different UV-B treatments, low UV-B (4% UV-B), high UV-B (92% UV-B), and ambient (100% UV-B). The egg experiment was conducted in lake and pond water, whereas proto- and mesolarval stage experiments were conducted in lake water only.

High and ambient UV-B radiation affected the hatching rate of golden shiner eggs. The mean hatching rate was 13% lower in high UV-B, and …


Bahamian Reef Communities: Composition, Recruitment And Change (10 Meters To 250 Meters), William E. Avery May 1998

Bahamian Reef Communities: Composition, Recruitment And Change (10 Meters To 250 Meters), William E. Avery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The composition, recruitment rates and fine-scale spatial dynamics of the sessile benthic community occupying hard substrata off Lee Stocking Island, The Bahamas, was determined through photography and the deployment of artificial substrata from September 1993 to September 1996. The study spanned 10 to 250 meters in depth. The benthic community exhibited a pronounced bathymetric zonation. Filamentous and macroalgae dominated the shallow communities, but were replaced by corals, sponges and endolithic algae with increasing depth. Living cover was high above 100 m, but declined significantly below this depth, being replaced by increasing amounts of bare and sediment-covered rock surfaces. Benthic zonation …


Ammonium And Nitrate Effects On Growth, Development And Nutrient Uptake Of Hydroponic Wheat, Thomas M. Hooten May 1998

Ammonium And Nitrate Effects On Growth, Development And Nutrient Uptake Of Hydroponic Wheat, Thomas M. Hooten

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The long-term effects of low and high NH4+/ NO3- uptake ratios in a system with rigorous control of pH and nitrogen concentration are poorly understood. In two replicate studies, two cultivars of wheat (Triticum aestivum) were grown to maturity with three NH4+/ NO3- ratios in hydroponic solution: 0/100, 25/75, and 85/15%. Nitrogen was controlled at ample levels throughout the 70-d life cycle and pH was controlled at 5.8 ± 0.2. An equimolar ratio of NH4+ to Cl- was used to facilitate charge balance. Nitrogen consumption …


Kokanee Fry Recruitment And Early Life History In The Lake Tahoe Basin, Christine K. Gemperle May 1998

Kokanee Fry Recruitment And Early Life History In The Lake Tahoe Basin, Christine K. Gemperle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lake Tahoe kokanee salmon have experienced decreasing mean adult size and fluctuating populations since 1970. We proposed to determine whether fish production was limited by spawning and incubation processes in Taylor Creek, or by growth constraints, or by mortality in the lake by studying egg-to-fry survival rates and early life history. Estimated egg-to-fry survival was 15. 9% for the 1994 brood year and 1.5% for the 1995 brood year. Egg-to-adult survival was 3.5% for the 1991 brood year and 5.9% for the 1992 brood year. Of the 35 possible survival scenarios, egg-to-fry survival was 7.5-20% and fry-to-adult survival (inlake phase) …


Rangeland Dynamics And Pastoral Development In The High Andes: The Camelid Herders Of Cosapa, Bolivia, Lita P. Buttolph May 1998

Rangeland Dynamics And Pastoral Development In The High Andes: The Camelid Herders Of Cosapa, Bolivia, Lita P. Buttolph

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current models of rangeland system dynamics were evaluated in Cosapa, a pastoral community on the Bolivian altiplano. Two specific models were tested: the "equilibrium" model, which assumes biotic interactions dominate rangeland dynamics and lead to system stability, and the "nonequilibrium" model, in which stochastic, abiotic factors control systems such that equilibrium is never attained. A livestock development project (called "Project Alpaca") working in the community was then assessed in terms of how its assumptions of system dynamics compared with empirical findings. The goal of Project Alpaca was to increase incomes for camelid (i.e., llama and alpaca) herders on the …


The Role Of Ammonia In Reproductive Inefficiency In High-Producing Dairy Cows Fed Excess Rumen Degraded Protein, Douglas Scott Hammon May 1998

The Role Of Ammonia In Reproductive Inefficiency In High-Producing Dairy Cows Fed Excess Rumen Degraded Protein, Douglas Scott Hammon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The role of ammonia in reproductive inefficiency in early lactation dairy cows was studied in a series of experiments designed to determine the concentrations of ammonia in normal bovine follicular fluid (bFF), to determine the effects of ammonia on the bovine embryo during specific stages of development, and to test the hypothesis that elevated plasma urea nitrogen concentration is associated with elevated ammonia and urea nitrogen concentrations in the reproductive fluids.

In the first study, ammonia concentration in different size follicles and the effect of ammonia during in vitro maturation on embryo development were determined. Ammonia concentration in the bFF …


Management Of Microbial Nitrate Production In Agricultural Soils, Wei Shi May 1998

Management Of Microbial Nitrate Production In Agricultural Soils, Wei Shi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrate (NO3-) is of central importance in the internal soil nitrogen (N) cycle. While animal wastes and nitrification inhibitors have been used in modern agriculture for decades, their effects on soil NO3- concentrations in relation to microbial NO3- production have not been well characterized. The objective of this research was to determine microbial NO3- production in relation to ammonium (NH4+) availability and nitrifier population activity in agricultural soils receiving animal wastes or nitrification inhibitors.

Several laboratory and field studies assessed the impacts of variously treated dairy wastes and …


Protein Production In The Milk Of Genetically Engineered Animals, Katherine M. Bates May 1998

Protein Production In The Milk Of Genetically Engineered Animals, Katherine M. Bates

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are numerous proteins that have potential uses in commercial and scientific applications that are not utilized to their full potential. this is partly because it is not economically feasible to isolate some of these proteins from their natural sources or to produce them using bacterial fermentation methods. The purpose of this research was to target recombinant protein expression to the mammary glands of genetically engineered or transgenic animals. Foreign protein expression has been achieved in the mammary glands of rabbits, sheep, cows, and swine. By using a strong mammary gland promoter and signal peptide fused to the protein, it …


The Effects Of Retinoic Acids On The Angiogenic Growth Factors Produced By Solid Tumors, Lynn C. Burgess May 1998

The Effects Of Retinoic Acids On The Angiogenic Growth Factors Produced By Solid Tumors, Lynn C. Burgess

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

These studies investigated the effects of retinoic acid (RA) on angiogenesis. Three human, neoplastic cell lines were used to examine angiogenic promotion and/or inhibition. The cell lines, U-373MG glioblastoma, DU-145 prostate carcinoma, and TCCSUP bladder transitional cell carcinoma, were treated with the following: all-trans, 9-cis, or 13-cis RA, at doses from 0.0001 to 100 μM. Hypoxia was used to assist the expression of the angiogenic phenotype. Conditioned media (CM) were prepared by growing the tumor cells in the presence of RA and hypoxia for 24 hours, and then the CM was transferred to bovine, capillary endothelial …


Modeling Soil Loss To Determine Water Erosion Risk At Camp Williams National Guard Base, Utah, Kevin P. Bartsch May 1998

Modeling Soil Loss To Determine Water Erosion Risk At Camp Williams National Guard Base, Utah, Kevin P. Bartsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil erosion was assessed at Camp Williams National Guard Base by creating an erosion risk classification map and comparing the erosion impact of disturbance regimes on different hillslopes. Soil erosion does not appear to be a problem for most of Camp Williams.

The Revised Universal Soil Loss Equation was applied using GIS to create a soil erosion risk map for the entire Camp Williams facility. The map indicated where problem areas occurred and showed relative erosion risk, but its lack of quantitative accuracy should be noted. Areas of concern included landscapes with little or no protective vegetation such as roads, …


Use Of The Water Erosion Prediction Project (Wepp) Model To Predict Road Surface Erosion In Mountain Rangeland Areas, Brian J. Zalewsky May 1998

Use Of The Water Erosion Prediction Project (Wepp) Model To Predict Road Surface Erosion In Mountain Rangeland Areas, Brian J. Zalewsky

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A significant source of sediment in many watersheds is that associated with the layout, construction, and maintenance of roadways. Much work has been done in more mesic forested environments with little or none in semiarid systems. Accurate estimation of runoff and sediment yield from native surfaced roads located in semiarid mountainous ecosystems is important to both private and public regulatory agencies. The Watershed Erosion Prediction Project (WEPP) model represents the most current erosion prediction technology. WEPP has been applied to the problems of logging road erosion in more mesic forests but has not been tested or evaluated on roadways located …


Limitations On Canada Goose Production At Fish Springs National Wildlife Refuge, Utah, Dorie S. Stolley May 1998

Limitations On Canada Goose Production At Fish Springs National Wildlife Refuge, Utah, Dorie S. Stolley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Canada geese (Branta canadensis) recently have become management problems in some areas due to overpopulation. At Fish Springs National Wildlife Refuge (NWR), managers are concerned with the opposite situation. Despite attempts to boost production, only 18 to 34 goslings of the western Canada goose (B. c. moffitti) were produced per year, from 1989 to 1993. I studied the breeding population from March to July in 1996 and 1997. Results suggest that production is limited in 3 ways: low gosling survival, low nesting success for ground nests, and low number of breeding pairs.

Gosling survival to fledging …


Characterization Of The Proteolytic System In Lactococcus Lactis Starter Cultures, Christina Beer May 1998

Characterization Of The Proteolytic System In Lactococcus Lactis Starter Cultures, Christina Beer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The proteolytic system of Lactococcus lactis starter cultures influences both flavor and the characteristic body and texture of cheese. The ability to further understand and control how different components of this proteolytic system work together to hydrolyze milk proteins would be of immense importance to the dairy industry.

The goal of this research was to characterize Lactococcus lactis subsp. lactis starter bacteria with varying prt operon compositions by proteinase specificity, aminopeptidase and lipase activities, growth, and influence on cheese flavor. By using a cheese slurry system, a statistical model to predict milk protein hydrolysis patterns was developed.

Lactococcus lactis subsp. …


Study Of Ripening Characteristics Of Full-Fat And Low-Fat Cheddar Cheese Using Fourier Transform Infrared Spectroscopy And Texture Analyzer, Manxiang Chen May 1998

Study Of Ripening Characteristics Of Full-Fat And Low-Fat Cheddar Cheese Using Fourier Transform Infrared Spectroscopy And Texture Analyzer, Manxiang Chen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A suitable microtome sampling technique was used to sample cheese for analysis using FTIR spectroscopy. Well-separated fat- and protein-related bands were obtained in the spectra of Cheddar and Mozzarella cheese samples using this method. The absorbance intensity of the spectra was proportional to the thickness of the sample. The intensity of absorbance and fat- and protein-related bands increased with an increase in the fat and protein content in the sample. Strong and well-separated bands at 1744, 1450, 1240, 1170, and 1115 cm-1 arising mainly from fat content were observed using this method. Bands observed at 1650 and 1540 cm …


Tryptophan Catabolism By Lactobacillus Spp. : Biochemistry And Implications On Flavor Development In Reduced-Fat Cheddar Cheese, Sanjay Gummalla May 1998

Tryptophan Catabolism By Lactobacillus Spp. : Biochemistry And Implications On Flavor Development In Reduced-Fat Cheddar Cheese, Sanjay Gummalla

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Amino acids derived from the degradation of casein in cheese serve as precursors for the generation of key flavor compounds. Microbial degradation of tryptophan (Trp) is thought to promote formation of aromatic compounds that impart putrid fecal or unclean flavors in cheese, but pathways for their production have not been established. This study investigated tryptophan catabolism by Lactobacillus casei LC301 and LC202 and Lactobacillus helveticus CNRZ32 and LH212 cheese flavor adjuncts in carbohydrate starvation (pH 6.5, 30 or 37°C, no sugar) and cheese-like conditions (pH 5.2, 4% NaCl, 15°C, no sugar). Enzyme assays of cell-free extracts revealed both species of …


Establishing Threshold Levels Of Nitrite Causing Pinking Of Cooked Meat, Kevin M. Heaton May 1998

Establishing Threshold Levels Of Nitrite Causing Pinking Of Cooked Meat, Kevin M. Heaton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sporadic problems with pink color defect, or pinking, has occurred in cooked meat products for decades. Pink color can be due to the presence of undenatured myoglobin, denatured globin hemochromes, or nitrosylhemochrome. This research documented the level of added nitrite that produced nitrosylhemochrome in processed meat rolls from fabricated beef round, pork shoulder, turkey breast, and chicken breast. For each meat type, preliminary studies were conducted to narrow the range at which added nitrite caused pinking. Subsequently, the nitrite levels were increased incrementally by 1-ppm, and pink color was measured by trained panelists and by a Hunter color meter. Nitrosylhemochrome …


The Effects Of A Very-Low-Calorie-Diet On Resting Energy Expenditure, Body Composition, And Biochemical Data In Obese Outpatients, Charlene A. Perkins May 1998

The Effects Of A Very-Low-Calorie-Diet On Resting Energy Expenditure, Body Composition, And Biochemical Data In Obese Outpatients, Charlene A. Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Obesity is a disease of major proportion in the United States. The Surgeon General has identified obesity as a national health problem that affects approximately 34 million Americans.

The aim of this study was to investigate the very-low-calorie diet, Optifast 70. Measurements for resting energy expenditure (REE} and body composition via circumference measurements (CBF} and infrared photospectromerty (NIR} with a Futrex 5000 were collected at weeks 1, 7, 13, 19, and 25. Biochemical data, including serum chemistry panel (SMA-12} and complete blood count (CBC}, were collected on weeks 1, 5, 9, 13, 17, 21, and 25. Lipid profiles were drawn …


Antioxidant Activity Of Carnosine And Phytate: Application As Meat Preservatives, Beom Jun Lee May 1998

Antioxidant Activity Of Carnosine And Phytate: Application As Meat Preservatives, Beom Jun Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The antioxidant activity of carnosine and phytic acid was investigated using several model systems. Carnosine and phytic acid alone inhibited metal ion-catalyzed deoxyribose degradation. Carnosine strongly inhibited metal ion-catalyzed lipid peroxidation in liposomes and in ground beef homogenates. Phytic acid facilitated oxidation of Fe (II) to Fe (III), and it inhibited hemeprotein + H2O2-catalyzed lipid peroxidation in linoleic acid micelles.

Antioxidant and color stabilizing effects of carnosine and phytate were investigated in a beef model system. Both compounds increased the rate of pH decline in pre-rigor beef muscle and stabilized fresh meat color by inhibiting metmyoglobin …


Short-Eared Owl Post-Fledging Survival And Breeding Season Diet, Thomas A. Rivest May 1998

Short-Eared Owl Post-Fledging Survival And Breeding Season Diet, Thomas A. Rivest

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

My research primarily focused on the survival of short-eared owls (Asio flammeus) from leaving the nest until their emigration from their natal territories during 1993 and 1994. I attached tarsal-mounted radio transmitters to nestlings prior to fledging. Of 25 fledgling short-eared owls monitored, 16 (64%) died prior to dispersal and one (4%) died after dispersing. Mammalian predation (5, 29.4%) was the primary cause of mortality followed by starvation (4, 23.5%), exposure (2, 11.8%), auto collision (1, 5.9%), burial (1, 5.9%), and unknown causes (4, 23.5%). Hatch date was found to be negatively correlated with fledgling survival.

A secondary …


Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke May 1998

Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heterogeneous spatial and temporal distributions of soil resources important to plant growth have been documented in the sagebrush steppe ecosystem. There can exist as much variability in soil resources within the root zone of individual plants as exists across an entire field. The objective of this dissertation research was to evaluate how plants respond to, utilize and influence the spatial heterogeneity of soil resources. The three specific sets of questions addressed are outlined in the three main chapters of this dissertation.

My first study addressed how the number and concentration of phosphorus (P) patches in the root zone of an …


Regeneration Ecology Of Chrysopogon Aucheri And Cymbopogon Jwarancusa In Grasslands Of Upland Balochistan, Pakistan, Sarfraz Ahmad May 1998

Regeneration Ecology Of Chrysopogon Aucheri And Cymbopogon Jwarancusa In Grasslands Of Upland Balochistan, Pakistan, Sarfraz Ahmad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Field experiments were conducted to investigate the seed attributes, movements and fates of dispersal units, and seedling establishment of Chrysopogon aucheri and Cymbopogon jwarancusa in a representative grassland ecosystem in upland Balochistan, Pakistan.

Cymbopogon jwarancusa had more filled and viable caryopses than Chrysopogon aucheri. Seeds (spikelets) of both species had similar morphological features. Chrysopogon aucheri had one dispersal unit, a triplet spikelet. Cymbopogon jwarancusa had four types of dispersal units: a paired spikelet, a partial raceme, an entire raceme, and a partial inflorescence comprised of two racemes.

Paired spikelets and partial racemes of Cymbopogon jwarancusa had greater …


Livestock Watering Practices In The Moroccan Pre-Sahara: Their Effects On Water And Nutrient Metabolism Of Sheep In Different Body Conditions, El Mostafa Darfaoui May 1998

Livestock Watering Practices In The Moroccan Pre-Sahara: Their Effects On Water And Nutrient Metabolism Of Sheep In Different Body Conditions, El Mostafa Darfaoui

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A field survey and a metabolism experiment were conducted to study livestock watering practices in the Moroccan Pre-Sahara and their changes with drought extent, season, ecological zone, pastoral system, and herd size. The metabolism experiment was designed to determine effects of once per 2 days (ID), once daily and twice daily drinking frequencies, and high and low body conditions on water and nutrient utilization by sheep fed high- and low-quality diets.

The way herds are managed in this region exposes all sex and age categories of animals to food and water shortages during annual dry seasons and occasional droughts. Livestock …


Predicting Transpiration Rates Of Hydroponically-Grown Plant Communities In Controlled Environments, Oscar Monje May 1998

Predicting Transpiration Rates Of Hydroponically-Grown Plant Communities In Controlled Environments, Oscar Monje

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Canopy transpiration is a major factor determining crop evapotranspiration and energy budgets. Unfortunately the development of robust models of canopy transpiration is hindered by a lack of reliable data due to the difficulties of making canopy-scale measurements. However, measurements of canopy water vapor and carbon fluxes via gas exchange techniques are possible in controlled environments. Simultaneous measurements of transpiration, photosynthesis, and canopy temperature were made in wheat and soybean communities. These data were used to calculate chamber aerodynamic and canopy stomata! conductances, and to model the response of canopy transpiration to CO2concentration and vapor pressure deficit. Canopy stomata! …