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Full-Text Articles in Life Sciences

Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz May 1975

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 …


Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal May 1975

Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The upper optimum temperature for embryonic development of mountain whitefish is 6 C, and for the post yolk sac stage is 9 to 12 C. The need to know effects on all stages in the life cycle in cases of thermal pollution is demonstrated. Abnormalities caused by thermal pollution in hatched larvae were agape jaws, coloboma or fissure of the eye, monophthalmia or the presence of only one eye, monomicrophthalmia or the presence of one small eye and one case of twinning. High mortalities of eggs occurred at 9 C and higher.

Study of the energy expenditure, by the dry …


Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray May 1975

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 …


Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski May 1975

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.


Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson May 1975

Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although water stress is an important selective force in many environments, it is not commonly considered to be of particular importance in tundra areas. Even though large portions of tundra may have an abundance of water, other more exposed areas may become quite dry. This microsite variability with respect to moisture stress was reflected in soil water potential measurements obtained from an alpine tundra area on Niwot Ridge in Colorado. Even though soil water potentials were consistently above -5 bars in a relatively low lying Deschampsia meadow, soil water potentials from an exposed fellfield area were often as low as …


Data Search For Aquatic Model, J. Perry Ii, G. W. Minshall Jan 1975

Data Search For Aquatic Model, J. Perry Ii, G. W. Minshall

Memorandum

No abstract provided.


Process Studies Related To The Deep Creek Ecosystem, C. W. Minshall, J. T. Brock, D. A. Mccullough, R. Dunn, M. R. Mcsorley, R. Pace Jan 1975

Process Studies Related To The Deep Creek Ecosystem, C. W. Minshall, J. T. Brock, D. A. Mccullough, R. Dunn, M. R. Mcsorley, R. Pace

Memorandum

No abstract provided.


Use Of The Normal Generating Distribution For Estimating Population Survival, H. C. Romesburg Jan 1975

Use Of The Normal Generating Distribution For Estimating Population Survival, H. C. Romesburg

Memorandum

No abstract provided.


Ecology Of Cool Desert Annuals, L. G. Klikoff, D. C. Freeman, N. Negus Jan 1975

Ecology Of Cool Desert Annuals, L. G. Klikoff, D. C. Freeman, N. Negus

Memorandum

No abstract provided.


Primary Production And Carbon Allocation In Creosotebush, G. L. Cunningham, J. P. Syvertsen, T. V. Feather Jan 1975

Primary Production And Carbon Allocation In Creosotebush, G. L. Cunningham, J. P. Syvertsen, T. V. Feather

Memorandum

No abstract provided.


Factors Contributing To Production And Distribution Of Chihuahuan Desert Annuals, P. D. Whitson Jan 1975

Factors Contributing To Production And Distribution Of Chihuahuan Desert Annuals, P. D. Whitson

Memorandum

No abstract provided.


Plant Productivity And Nutrient Interrelationships Of Perennials In The Mohave Desert, A. T. Vollmer, S. A. Bamberg, A. Wallace, J. W. Cha Jan 1975

Plant Productivity And Nutrient Interrelationships Of Perennials In The Mohave Desert, A. T. Vollmer, S. A. Bamberg, A. Wallace, J. W. Cha

Memorandum

No abstract provided.


Effects Of Grazing On Desert Vegetation, B. E. Norton Jan 1975

Effects Of Grazing On Desert Vegetation, B. E. Norton

Memorandum

No abstract provided.


Responses And Interactions In Desert Plants As Influenced By Irrigation And Nitrogen Applications, R. B. Hunter, E. M. Romney, J. W. Childress, J. E. Kinnear Jan 1975

Responses And Interactions In Desert Plants As Influenced By Irrigation And Nitrogen Applications, R. B. Hunter, E. M. Romney, J. W. Childress, J. E. Kinnear

Memorandum

No abstract provided.


Rock Valley Validation Site Report, F. B. Turner Jan 1975

Rock Valley Validation Site Report, F. B. Turner

Memorandum

No abstract provided.


Water Loss In Chihuahuan Desert Ants, W. G. Whitford, C. A. Kay, A. M. Schumacher Jan 1975

Water Loss In Chihuahuan Desert Ants, W. G. Whitford, C. A. Kay, A. M. Schumacher

Memorandum

No abstract provided.


Rodent Seed Foraging Strategies And Competition With Ants In The Sonoran Desert, J. H. Brown Jan 1975

Rodent Seed Foraging Strategies And Competition With Ants In The Sonoran Desert, J. H. Brown

Memorandum

No abstract provided.


Factors Affecting Seed Reserves In The Soil Of A Desert Ecosystem, R. M. Chew, J. F. Nelson Jan 1975

Factors Affecting Seed Reserves In The Soil Of A Desert Ecosystem, R. M. Chew, J. F. Nelson

Memorandum

No abstract provided.


Effects Of Rodents On Germination Of Desert Annuals, O. J. Reichman Jan 1975

Effects Of Rodents On Germination Of Desert Annuals, O. J. Reichman

Memorandum

No abstract provided.


Plant Response To Insect Herbivory, B. E. Norton, L. B. Smith Jan 1975

Plant Response To Insect Herbivory, B. E. Norton, L. B. Smith

Memorandum

No abstract provided.


Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, P. L. Comanor Jan 1975

Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, P. L. Comanor

Memorandum

No abstract provided.


Measurement Of Evapotranspiration With A Monolith Lysimeter, D. W. Young, D. D. Evans, T. W. Sammis Jan 1975

Measurement Of Evapotranspiration With A Monolith Lysimeter, D. W. Young, D. D. Evans, T. W. Sammis

Memorandum

No abstract provided.


Effect Of Soil Water Potential On Soil Moisture Absorption, Transpiration Rate, Plant Water Potential And Growth For Artemisia Tridentata, G. S. Campbell, G. S. Harris Jan 1975

Effect Of Soil Water Potential On Soil Moisture Absorption, Transpiration Rate, Plant Water Potential And Growth For Artemisia Tridentata, G. S. Campbell, G. S. Harris

Memorandum

No abstract provided.


Further Development Of A Stream Ecosystem Model, J. H. Wlosinski, G. W. Minshall Jan 1975

Further Development Of A Stream Ecosystem Model, J. H. Wlosinski, G. W. Minshall

Memorandum

No abstract provided.


Curlew Valley Validation Site Report, R. S. Shinn, R. D. Anderson, M. Merritt, W. Osborne, J. A. Macmahon Jan 1975

Curlew Valley Validation Site Report, R. S. Shinn, R. D. Anderson, M. Merritt, W. Osborne, J. A. Macmahon

Memorandum

No abstract provided.


Gas Exchange, Translocation, Root Growth And Soil Respiration Of Great Basin Plants, M. M. Caldwell, E. J. Depuit, O. A. Fernandez, H. H. Wiebe, L. B. Camp, R. S. Holthausen, H. Neuber Jan 1975

Gas Exchange, Translocation, Root Growth And Soil Respiration Of Great Basin Plants, M. M. Caldwell, E. J. Depuit, O. A. Fernandez, H. H. Wiebe, L. B. Camp, R. S. Holthausen, H. Neuber

Memorandum

No abstract provided.


Effect Of Density On The Population Dynamics Of Perognathus Formosus And Its Relationships Within A Desert Ecosystem, R. M. Chew Jan 1975

Effect Of Density On The Population Dynamics Of Perognathus Formosus And Its Relationships Within A Desert Ecosystem, R. M. Chew

Memorandum

No abstract provided.


The Functional Relationships Among The Organisms Comprising Detritus-Based Foodchains At The Rock Valley Site, J. F. Mcbrayer, G. E. Mamolito, P. J. Franco Jan 1975

The Functional Relationships Among The Organisms Comprising Detritus-Based Foodchains At The Rock Valley Site, J. F. Mcbrayer, G. E. Mamolito, P. J. Franco

Memorandum

No abstract provided.


Studies On Wood Borers, Girdlers And Seed Predators Of Mesquite, W. G. Whitford, R. K. Johnson, D. J. Depree Jan 1975

Studies On Wood Borers, Girdlers And Seed Predators Of Mesquite, W. G. Whitford, R. K. Johnson, D. J. Depree

Memorandum

No abstract provided.


Plant Growth And Water Transfer Interactive Processes Under Desert Conditions, D. D. Evans, T. W. Sammis Jan 1975

Plant Growth And Water Transfer Interactive Processes Under Desert Conditions, D. D. Evans, T. W. Sammis

Memorandum

No abstract provided.