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Effects Of Heavy Metals (Cadmium, Copper, And Mercury) On Reproduction, Growth, And Survival Of Brine Shrimp (Artemia Salina) From The Great Salt Lake, Karl A. Gebhardt
Effects Of Heavy Metals (Cadmium, Copper, And Mercury) On Reproduction, Growth, And Survival Of Brine Shrimp (Artemia Salina) From The Great Salt Lake, Karl A. Gebhardt
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this paper is to report findings concerning the effects of cadmium, copper, and mercury on the brine shrimp Artemia Salina, of the Great Salt Lake. Metal toxicity was observed in relation to acute susceptibility, growth, reproduction, and hatching of the brine shrimp.
Heavy metal concentrations such as cadmium, copper, and mercury are known to be considerably higher in the Great Salt Lake than those in both freshwater and seawater. No published study has been concerned with heavy metal effects on organisms in salinities greater than seawater (35 grams per liter total dissolved solids). The experiments reported …
Host And Habitat Preferences, Life History, Pathogenicity And Population Regulation In Species Of Protocalliphora Hough (Diptera: Calliphoridae), Terry Lee Whitworth
Host And Habitat Preferences, Life History, Pathogenicity And Population Regulation In Species Of Protocalliphora Hough (Diptera: Calliphoridae), Terry Lee Whitworth
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The host, habitat preferences, and life histories of species of Protocalliphora were investigated in northern Utah. The effect of species of Protocalliphora on blood levels (hematocrit and hemoglobin) and weight gains of nestling birds also was studied.
A total of 1,819 bird nests were examined, representing 68 bird species from 10 habitats. Forty-eight percent (869) of the nests of 51 bird species found were infested. Eighteen species of Protocalliphora, including 11 undescribed, were collected.
Birds experiencing a high rate of infestation included most colonial nesters (such as bank swallows and yellow-headed blackbirds), cavity nesters (such as starlings and tree swallows, …
Breeding Biology And Pesticide-Pcb Contamination Of Western Grebe At Bear River Migratory Bird Refuge, Mark L. Lindvall
Breeding Biology And Pesticide-Pcb Contamination Of Western Grebe At Bear River Migratory Bird Refuge, Mark L. Lindvall
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The breeding biology of western grebe was studied at Bear River Migratory Bird Refuge, Utah in 1973 and 1974. More than 300 nests were located and data gathered on nesting habitat and success. Western grebe at Bear River selected nest sites for nearness to open water of approximately 30 em in depth. At least one young was hatching in 21 percent of the nests. Avian predation and abandonment of nests following drops in water levels caused the greatest loss of nests. Chlorinated hydrocarbons monitored in western grebes showed DDE, DDD, PCB, 1260, and PCB 1254 levels in 24 breast muscle …
Ecology Of The Common Snipe In Northern Utah, Samuel C. Winegardner
Ecology Of The Common Snipe In Northern Utah, Samuel C. Winegardner
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The study addresses five areas relating to the biology and management of common snipe (Capella gallinago), including habitat requirements, food habits, breeding biology, sexing and aging and census techniques.
The primary habitat requirement of snipe was determined to be areas that were saturated or covered with shallow water. Secondary requirements were vegetation of less than 3 decimeters in height and between 30 and 50 percent density.
Food habit studies determined that snipe selected animal material with larger and more abundant organisms being preferred without regard to species . Plant material appeared to be ingested only incidentally.
Common snipe …
Migration Patterns Of High School Vocational Agricultural Graduates Of Utah In 1949 And A Comparison With Ohio Graduates, Keith L. Smith
Migration Patterns Of High School Vocational Agricultural Graduates Of Utah In 1949 And A Comparison With Ohio Graduates, Keith L. Smith
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of the study was to determine the migration patterns of vocational agricultural graduates in Utah during the first 5 years following their high school graduation in 1969, and compare these patterns with Ohio graduates of 1963. Former graduates of 23 of the qualifying 28 departments were included in this study. A random sample of students were surveyed.
Forty percent of the 1969 graduates were engaged in agricultural occupations or agricultural study in college. A total of 30.6 percent of the graduates had moved from their home communities since graduating from high school. More than 88 percent of the …
Assessment Of Possible Carcinogenic Hazards Created In Surrounding Ecosystems By Oil Shale Developments, Gerald L. Dassler
Assessment Of Possible Carcinogenic Hazards Created In Surrounding Ecosystems By Oil Shale Developments, Gerald L. Dassler
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
One of the purposes of an environmental assessment is to foresee potential problems created by the introduction of contaminants into an ecosystem and to suggest appropriate control devices to mitigate the effects of such inputs. In the case of the oil shale industry, very little is known about the potential hazards, especially those related to the emission of organic compounds with carcinogenic potency. The hazards will probably be due to chronic exposures to the emitted compounds and the effects of such exposures are likely to take years to manifest themselves, as is the case with many carcinogenic substances. A precise …
Adjustment Of Persian Students At Utah State University, Homa Aflatouni
Adjustment Of Persian Students At Utah State University, Homa Aflatouni
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Social adjustment of Persian students in terms of their social participation with Americans is analyzed by correlation and multiple regression analyses with six independent variables. The six independent variables are: education, attitude, time, English, social class, and religion. The results of correlation and multiple regression analyses support some of the hypotheses. The significant finding is that the level of education the Persian students completed before coming to the United States, their attitudes toward the Americans, and the length of stay in the United States are the most important factors while other variables are much less useful.
Nitrogen Fertilization Studies In Dryland Winter Wheat And Potential Nitrogen Losses From The Soil At The Blue Creek Experimental Station In Northern Utah, Subhawat Intalop
Nitrogen Fertilization Studies In Dryland Winter Wheat And Potential Nitrogen Losses From The Soil At The Blue Creek Experimental Station In Northern Utah, Subhawat Intalop
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This study compared the effects of nitrogen sources on the available inorganic soil nitrogen, nitrogen movement, nitrogen losses, and wheat yields when nitrogen fertilizers were applied to soil planted to dryland winter wheat at the Blue Creek Experimental Station in northern Utah.
In the fall 1973 soil samplings, the fertilizers producing the largest mineral nitrogen contents in the 0-30 cm soil depths were ammonium nitrate > ammonium sulfate > S-coated urea, when they were broadcast at the practical rate of 56 kg N/ha. There was no increase in the mineral nitrogen at the deeper depths in the fall or at any depth …
Aerial Photography In Estimating Waterfowl Populations In Northern Utah, Timothy H. Provan
Aerial Photography In Estimating Waterfowl Populations In Northern Utah, Timothy H. Provan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this project was to evaluate effectiveness of aerial photography as a waterfowl census technique. An aerial photographic pattern was formulated and tested during the spring and fall months of 1971 and 1972 at Ogden Bay Waterfowl Management Area, Weber County, Utah. The reliability and feasibility of the technique for censusing waterfowl proved effective and practical.
Eight flights per season, 4 routes per flight, and 30 photos per route taken over unit 1 of the Ogden Bay Waterfowl Management Area was the experimental design or pattern for the study. The level of accuracy and the cost involved with …
Development Of A Water Quality Model Applicable To Great Salt Lake, Utah, Craig T. Jones
Development Of A Water Quality Model Applicable To Great Salt Lake, Utah, Craig T. Jones
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The development of a model capable of predicting the long term (seasonal) distribution of water quality constituents within Great Salt Lake was undertaken as a portion of the ongoing Great Salt Lake project at Utah State University. The overall goal of the project is the development of a modeling framework to assist the relevant decision making bodies in the comprehensive management of the Great Salt Lake system. Phase I of the project provided the overall structural framework for management of the Great Salt Lake system, identified data needs, and established priorities for the development of submodels for incorporation into the …
Plant Demographic Studies Of Tall Threetip Sagebrush-Grass Vegetation On The Eastern Snake River Plains, Idaho, Kenneth Harold Rea
Plant Demographic Studies Of Tall Threetip Sagebrush-Grass Vegetation On The Eastern Snake River Plains, Idaho, Kenneth Harold Rea
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
It has commonly been assumed that grazing decreases the longevity of plants, however, very few studies address this question. Knowledge of mean age, longevity and other aspects of population dynamics would help improve estimates of productivity and nutrient cycling and aid understanding of range condition and trend. These data would also aid in developing a theory of community organization and control.
As a step toward these ends, pantograph records from twelve 1 m2 plots established at the U. S. Sheep Station on the Snake River Plains of southeastern Idaho between 1923 and 1935 were examined. The plots were mapped …
Selected Vitamin Status Of Elderly People In Southern Utah Measured Biochemically And Dietarily, And Correlated To Their Perceived Status, Karen Sims Faddis
Selected Vitamin Status Of Elderly People In Southern Utah Measured Biochemically And Dietarily, And Correlated To Their Perceived Status, Karen Sims Faddis
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study was to analyze the diets of elderly people in southern Utah. Three types of information were used in the analysis: biochemical, dietary, and the subject's analysis of his diet. Four vitamins were studied: vitamin A, ascorbic acid, thiamin, and riboflavin.
Dietary data was obtained on the four vitamins and compared by sex and by age. Thiamin and riboflavin dietary levels were evaluated using the Index of Nutritional Quality (INQ), to determine the quality of the diet according to the total calories consumed. Seasonal differences between fall and spring data were evaluated.
Plasma vitamin A, plasma …
Plant Demographic Studies Of A Desert Annuals Community In Northern Utah Dominated By Nonnative Weedy Species, David R. Duba
Plant Demographic Studies Of A Desert Annuals Community In Northern Utah Dominated By Nonnative Weedy Species, David R. Duba
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Field and laboratory investigations were conducted relating to factors controlling distribution and abundance of annual species growing in a disturbed portion of the salt desert shrub zone on fine-textured soils. Dominant species on the site in the two study years were the nonnative, Halophytic, late-summer maturing, Halogeton glomeratus (Bieb.) C.A. Mey., and Bassia hyssopifolia (Pall.) Kuntze. Contrasting amounts of precipitation were received in the two years; in 1974, spring conditions were so dry that two early-maturing, sub-dominant annuals, Descurainia pinnata (walt.) Britton, and Lepidium perfoliatum L. were essentially absent. They successfully reproduced under more favorable 1975 conditions.
Studies on species …
Nitrogen Cycling In A Microcosm Simulation Of The Northern Arm Of The Great Salt Lake, John C. Stube
Nitrogen Cycling In A Microcosm Simulation Of The Northern Arm Of The Great Salt Lake, John C. Stube
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen cycling was studied in the hypersaline northern arm of the Great Salt Lake (332,480 mg/l total dissolved solids) using a sediment-water microcosm simulation of that system. The study demonstrated that nitrate, ammonia, and urea were not stimulating to the halophilic bacteria in the microcosm. The bacteria were simulated only indirectly simulated bacterial growth. In addition, no nitrification could be demonstrated during the study.
Weekly analyses of water samples from the north arm of the lake itself showed that nitrate and nitrite were absent, leaving ammonia as the only significant form of inorganic nitrogen in the northern lake basin. Other …
Error Patterning And Hypothesis Behavior Of Children And Pigeons In Discrimination Learning, William Robert Jenson
Error Patterning And Hypothesis Behavior Of Children And Pigeons In Discrimination Learning, William Robert Jenson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Characteristic distributions of errors across fixed ratio schedules of reinforcement were studied for two types of discrimination paradigms. Two experiments studied error patterns as a function of hypothesis behavior in two species of animals, children and pigeons.
Three key zero-delay matching-to-sample and two key simultaneous discrimination were reinforced for both species of animals on fixed ratio schedules of reinforcement. Experiment 1 involved children on matching-to-sample and simultaneous discrimination, and Experiment 2 involved pigeons on matching-to-sample and simultaneous discrimination. Both species of subjects experienced experimental conditions in which shift or stay response hypotheses were selectively reinforced using a high speed digital …
Religious Commitment And Meaning In Life, Merrill L. Barfield
Religious Commitment And Meaning In Life, Merrill L. Barfield
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study was to investigate the relationship between meaning or purpose in life as measured by Crumbaugh's Purpose in Life Test, and the degree of religious commitment of college students, with particular interest in the members of the Church of Jesus Christ of Latter-day Saints (LDS). Religious commitment was measured by Hoge's Intrinsic Religious Motivation Scale (IRM).
Two hundred and fifty-five undergraduates, 122 males and 132 females, enrolled in introductory psychology and sociology classes at Utah State University during spring quarter, 1975, served as subjects.
A two-way analysis of variance calculated separately for the LDS and non-LDS …
Strengths Enhancement Training: Self-Concept And Self-Actualization, Tony J. Strelich
Strengths Enhancement Training: Self-Concept And Self-Actualization, Tony J. Strelich
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The strengths enhancement training program was developed and evaluated in order to determine empirically if a group method designed specifically to assist subjects in the identification of personal strengths, resources, and potentials, would be effective in broadening their perceptions of themselves in a positive direction.
The strengths enhancement training program was based primarily on the work of Herbert A. Otto, using the Multiple Strengths Perception method as the central component of the training program. That method was pilot tested, and program modifications were made on two occasions.
A pretest-posttest control group design was used to assess the 80 Introductory Psychology …
Some Characteristics Of Female College Students Who Select Academic Majors In Fields Of Exact Science And Non-Exact Science: A Longitudinal Follow-Up, Paul David Warner
Some Characteristics Of Female College Students Who Select Academic Majors In Fields Of Exact Science And Non-Exact Science: A Longitudinal Follow-Up, Paul David Warner
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The present study, conducted in 1974, was a longitudinal follow-up of two groups of female subjects who had participated in an earlier study (Wright and Johnson, 1960) while the subjects were university students. One group of the subjects had majored in fields considered at that time to be traditionally feminine majors, i.e. social sciences, art, music, education, homemaking, etc. The other group had majored in fields of exact sciences, which at the time were considered more traditionally masculine. The purpose of the present study was to determine whether differences noted in the 1960 study will exist between these two groups …
Quantitation Of Aliphatic Aldehydes In Rancid Turkey Meat Using A Substituted Hydrazone, Stanley J. Andrews
Quantitation Of Aliphatic Aldehydes In Rancid Turkey Meat Using A Substituted Hydrazone, Stanley J. Andrews
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Many objective chemical tests have attempted to correlate with organoleptic evaluation of oxidative rancidity. Major chemical tests used to detect oxidative rancidity of lipids measure nonvolatile high molecular weight carbonylic substances which make no considerable contribution to rancid flavors. High molecular weight carbonyls are present at much greater concentrations than volatile low molecular weight carbonyls. Peroxides and other unknown substances also react in these chemical tests to give at best an empirical evaluation. A 3-methyl-2-benzothiazolinone hydrazone chemical test is proposed which corrected some deficiencies of earlier procedures, and was correlated with organoleptic evaluation of rancid turkey samples. The proposed test …
Some Effects Of Mechanical Deboning On The Composition And The Bioavailability Of Protein And Iron In Turkey Frame Meat, Lowell C. Allred
Some Effects Of Mechanical Deboning On The Composition And The Bioavailability Of Protein And Iron In Turkey Frame Meat, Lowell C. Allred
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Meat was obtained from a single daily lot of turkey frames by mechanically deboning with a Beehive AU 4171 deboner and by hand deboning. The meat was analyzed for protein, fat, moisture, ash, iron, calcium, and 19 amino acids. Mechanically deboned turkey had 68 percent more ash, 74 percent more iron, and nine times more calcium than the hand deboned turkey meat. Other constituents were about equal in the two products. Protein bioavailability tests, including protein efficiency ratio, biological value, net protein utilization, and nitrogen efficiency for growth, did not reveal significant differences between mechanically deboned and hand deboned turkey. …
A Longitudinal Study, Part Iii: The Relationship Of Weight, Health Status, Diet And Anxiety To Serum Cholesterol Levels In Adults, Kristine S. Saunders
A Longitudinal Study, Part Iii: The Relationship Of Weight, Health Status, Diet And Anxiety To Serum Cholesterol Levels In Adults, Kristine S. Saunders
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Over an 18-year period, beginning in 1955, a group of subjects has been studied six times to determine if any relationship exists among serum cholesterol levels, body weight, health status, diet quality and stress or anxiety. For the first four test periods, extending through ages 7 to 16 years, there were 321 subjects. Later, in 1968, 86 of the original 321 subjects, now aged 19-22 years, were able to participate in a follow-up study. The 1974 study was able to involve 30 of the original 321 subjects now aged 26-29 years. Findings show that from approximately the fifteenth year onward …
Insect Consumption Of Seeded Rangeland Herbage In A Selected Area Of Diamond Fork Canyon, Utah County, Utah, Diane M. Bowers
Insect Consumption Of Seeded Rangeland Herbage In A Selected Area Of Diamond Fork Canyon, Utah County, Utah, Diane M. Bowers
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This study compares insect and cattle consumption of crested wheatgrass (Agropycon spp.) on a site in Sterling Ranch, Utah County, Utah. The hypothesis tested is that insect consumption in general, and specifically consumption by Labops hesperius Uhler, significantly reduces total available cattle forage.
Labops and grasshoppers were probably the major cause of secondary damage at the study site, while the impact of thrips is unknown. A detrimental impact on range was suggested by the data, as insects consumed forage equivalent to 2.8 animal units per month, while cattle consumed forage equivalent to 2.1 animal units per month at the …
Irrigation Scheduling Program For Sugarcane, Terence L. Pearse
Irrigation Scheduling Program For Sugarcane, Terence L. Pearse
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
An estimate of potential evapotranspiration is acquired to implement an irrigation scheduling program. Four equations, which estimate potential evapotranspiration (evaporation) were evaluated for prediction of Class "A" Pan evaporation. The equations used were Penman's combination equation, the Jensen-Haise temperature and radiation equation, and two of the Christiansen-Hargreaves polynomial regression type equations. Measured and calculated radiation was used together with two values of albedo. Four years of daily climate data from Rhodesia was evaluated by general linear regression methods.
Despite the significant variations between the four annual regression lines of each equation, the use of confidence intervals indicate that the Penman …
Model Studies For Molybdenum Enzymes. The Reduction Of Cytochrome C By Molybdenum(V)-Cysteine Complexes, Glen D. Lawrence
Model Studies For Molybdenum Enzymes. The Reduction Of Cytochrome C By Molybdenum(V)-Cysteine Complexes, Glen D. Lawrence
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The reduction of ferricytochrome c ( cyt cIII), as well as some iron ligand complexes and chemically modified derivatives of cyt cIII, by two molybdenum(V)-cysteine complexes has been investigated as a model for electron transfer in molybdenum enzymes. The reduction of cyt cIII by di-μ-oxo-bis [oxo(L-cysteinato)molybdate(V)] (I) is first order in cyt cIII and zero order in I over a wide range in concentration of I at neutral pH. The reduction of cyt cIII by μ-oxo-bisfoxodihydroxo(L-cysteinato) molybdate(V)] (II) is first order in both reactants and has a rate several orders of magnitude greater …
Ecological Management Of The Alfalfa Leafcutter Bee, Megachile Pacifica (Panzer), With Emphasis On Diapause Induction, Ron M. Bitner
Ecological Management Of The Alfalfa Leafcutter Bee, Megachile Pacifica (Panzer), With Emphasis On Diapause Induction, Ron M. Bitner
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The effects of photoperiod and temperature on diapause induction in the alfalfa leafcutter bee, Megachile pacifica (Panzer) (=M. rotundata Auct.), were studied during the summers of 1972, 1973 and 1974, The influence of photoperiod and temperature on mortality, rate of development and incidence of diapause was measured during the developmental stages of this insect. The aim of this research was to assess the potential for manipulation of the number of generations of this bee per season so as to develop a practical and ecologically-sound method of management,
Eggs, larvae, pupae and adults of M. pacifica were subjected to regimens …
Food Interactions Between Utah Prairie Dogs And Cattle, Dennis Crocker-Bedford
Food Interactions Between Utah Prairie Dogs And Cattle, Dennis Crocker-Bedford
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This study examined the food interactions between Utah prairie dogs (Cynomys parvidens, Allen) and cattle (Bos taurus). During 1974 and 1975, three prairie dog colonies near Panguitch, Utah, were studied intensely: "Oldfield" was chosen to represent colonies near fields of alfalfa (Medicago sativa); "Lowercrested" was chosen to represent colonies below 2,200 meters above sea level (a.s.l.) which were not near alfalfa, and "Uppercrested" was chosen to represent colonies above 2,200 meters a.s.l. which have been planted with crested wheatgrass.
Visual observations were made of Utah prairie dogs to determine their diets. Livetrapping of prairie …
Feeding Behavior Of Pen Reared Mule Deer Under Winter Range Conditions, Michael A. Smith
Feeding Behavior Of Pen Reared Mule Deer Under Winter Range Conditions, Michael A. Smith
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This study examined the feeding responses of mule deer to a system of spring livestock grazing. The specific purposes were 1) to determine botanical composition of diets selected by mule deer on a winter range subjected to previous spring grazing by sheep compared to one with no sheep grazing and 2) to develop a basis for predicting selection of individual plants by deer, based on physical characteristics of the plants and the species and physical proximity of associated plants.
The study was conducted within the framework of a completely randomized experimental design with two treatments. Variables controlled for each unit …
Photosynthesis, Dark Respiration, And Growth Of Rumex Patientia L. Exposed To Uv-B (280-315 Nm) Irradiance Corresponding To Reduced Atmospheric Ozone Concentrations, William B. Sisson
Photosynthesis, Dark Respiration, And Growth Of Rumex Patientia L. Exposed To Uv-B (280-315 Nm) Irradiance Corresponding To Reduced Atmospheric Ozone Concentrations, William B. Sisson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Net photosynthesis, dark respiration, chlorophyll concentrations and growth were determined for Rumex patientia L. exposed to UV-B radiation corresponding to reduced atmospheric ozone concentrations. The hypothesis of whether reciprocity is maintained in the response of R. patientia to polychromatic UV-B radiation was tested. On the basis of the relationships derived from these studies, a simulation model was developed for the prediction of photosynthesis and growth of R. patientia exposed to UV-B radiation corresponding to any atmospheric ozone reduction.
Photosynthetic rates were found to be depressed after two hours exposure to UV-B irradiance simulating a 0.18 atm·cm ozone column when the …
Socioecology Of The Vicuna, William L. Franklin
Socioecology Of The Vicuna, William L. Franklin
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The social organization of the vicuna (Vicugna vicugna) and its relationship to the environment were studied at the Pampa Galeras National Vicuna Reserve in southern Peru from May 1968 to April 1971. Behavioral data were collected on groups within a grid of 12.4 km2 during 3,800 hours of observation. The vicuna's alpine grassland environment was characterized by greatly fluctuating and freezing temperatures, light precipitation, high evaporation, wind, short growing seasons, shallow and infertile soils and low plant production. Vicuna habitat quality was dependent upon high producing, preferred vegetation types and close access to permanent water and a …
Seasonal Patterns Of Photosynthesis And Respiration In Atriplex Confertifolia And Ceratoides Lanata, Richard S. White
Seasonal Patterns Of Photosynthesis And Respiration In Atriplex Confertifolia And Ceratoides Lanata, Richard S. White
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Net photosynthesis and dark respiration studies were conducted on Atriplex confertifolia (Torr. and Frem.) S. Wats and Ceratoides lanata (Pursh) J.T. Howell under field and laboratory conditions. These woody species are commonly found in salt desert shrub communities of the Intermountain West. During these investigations, the effects of air temperature, plant moisture stress, soil water potential, irradiation, and plant phenological status were examined with respect to their influence on carbon dioxide (CO2) exchange.
Intensive field studies were carried out between April and October. This interval corresponded to the major period of physiological activity in both species. The factors …