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Theses and Dissertations

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The Plant Communities Of Arches National Park, John Stevens Allan Aug 1977

The Plant Communities Of Arches National Park, John Stevens Allan

Theses and Dissertations

Arches National Park, located in southeastern Utah, lies in a transition zone between the southwestern hot desert and the western cold desert, but it is floristically most similar to the hot desert. The major plant communities are as follows: Juniper-pinyon, blackbrush, grasslands and sand dune association. Other community types occur but occupy very limited areas. All of the communities studied have a high degree of uniqueness and merit recognition as separate entities. Blackbrush showed the greatest overall similarity to other communities and was most similar to the sand dune communities. The hanging gardens were the most distinctive and covered the …


Plant Dioecy, Ecology, Evolution And Sex Reversal, D. Carl Freeman Aug 1977

Plant Dioecy, Ecology, Evolution And Sex Reversal, D. Carl Freeman

Theses and Dissertations

The distribution of dioecious species among forty-four plant communities of western United States was examined. The dioecious habit is most prevalent in harsh environments. In many communities, over 20 percent of the species and 40 percent of the individuals are dioecious. Dioecy is most common among woody species which are pollinated by wind. It is concluded that inbreeding depression alone is insufficient to account for all known facts concerning dioecy. Disruptive selection acting upon differential success of gametes produced on sites of differing quality appears to have played a major role in producing separate sexed individuals. Dioecious species reported to …


The Genus Haemolaelaps (Acarina: Laelapidae) In The Northwest Ethiopian Biogeographical Region, Calvin J. Sakamoto May 1977

The Genus Haemolaelaps (Acarina: Laelapidae) In The Northwest Ethiopian Biogeographical Region, Calvin J. Sakamoto

Theses and Dissertations

This paper presents the results of a taxonomic stury of mites of the genus Haemolaelaps collected from small mammals of 8 political subdivisions of the northwest portion of the Ethiopian Biogeographical Region. Specimens taken from 2,863 small mammals from a wide variety of habitats and localities were examined. The Haemolaelaps fauna includes 23 species, 10 of which are described as new: H. bellasoma, H. caurinus, H. chaetospinicus, H. crocidura, H. desmodilliscus, He. ebsi, H. malachela, H. parahirsti, H. sikapusi and H. taterakempi. Numerical taxonomic and multicariate analyses were used to assess variation and clustering. A key for identification of females …


Modeling Studies Of Small Mammal Trapping Phenology, And Plant Succession In The Kaiparowits Region, Kane County, Utah, James A. Raines Apr 1976

Modeling Studies Of Small Mammal Trapping Phenology, And Plant Succession In The Kaiparowits Region, Kane County, Utah, James A. Raines

Theses and Dissertations

This study makes use of simple statistical models which may be manipulated for projection of changes in the Kaiparowits Region of Southern Utah. A method of determining habitat preferences of small rodents from capture-recapture trapping data is proposed. It is suggested that some aspects of animal behavior regarding trapping may also be explained. Timing of flowering of Oryzopsis hymenoides and Hilaria jamesii as related to enviromental conditions was investigated, and models of the requisite conditions proposed. It is suggested that similar models may be used to describe the timing of other phenological events. Succession on disturbed sites is considered to …


Use Of Selected Macroinvertebrates As Indicators Of Sedimentation Effects On Huntington River, Utah, Michael Kenneth Reichert Mar 1975

Use Of Selected Macroinvertebrates As Indicators Of Sedimentation Effects On Huntington River, Utah, Michael Kenneth Reichert

Theses and Dissertations

Benthic macroinvertebrate communities of Huntington River, Emery County, Utah were studied to determine effects of sedimentation from construction of Electric Lake Dam, a state highway, and two bridges. Approximately 900 benthic samples were collected from riffle areas above, in, and below the construction zone from January, 1971 to December, 1973. Two settling basins below construction sites were effective in limiting scouring of downstream communities. Heavy silt deposition was limited to a 1-km stream reach. Number of indicators, density, and biomass were reduced in the construction zone during periods of sediment input. During periods of scouring, density and biomass were reduced; …


The Algae Of Huntington Canyon, Utah, Carol Jean Endsley Aug 1974

The Algae Of Huntington Canyon, Utah, Carol Jean Endsley

Theses and Dissertations

A taxonomic study of the algae of Huntington canyon, Emery County, Utah, was conducted from March 1971 to April 1972. The algal flora of this cold, fast-flowing, hard-water mountain creek consisted of ninety-five genera, one hundred ninety-six species, twenty-nine varieties, and two forms. This diverse flora was dominated by many different species with usually rather few individuals of Achnanthes, Cymbella, Diatoma, Gomphonema, Lyngbya, Navicula, Nitzschia, Oscillatoria, Synedra, and Ulothrix.


Perception And Land Use: The Case Of The Mormon Culture Region, Lester D. Campbell Jan 1974

Perception And Land Use: The Case Of The Mormon Culture Region, Lester D. Campbell

Theses and Dissertations

Since the first man perceived and used his environment, there has existed a reciprocal man-land relationship. The physical environment provides opportunities for man's use and also sets limitations. Man's perception and use of his environment is greatly influenced by his culture, which consists of past experience, technology, attitudes, and needs. It is these factors that determine what a man will see as possibilities in land use, and how he will use his environment.

In the case of the relic Mormon Culture Region, Mormon religious beliefs highly influenced perception of the environment. Most visual geographical features of the landscape in the …


The Open Classroom, Joseph E. Tyney Jan 1973

The Open Classroom, Joseph E. Tyney

Theses and Dissertations

No abstract provided.


A Quantitative And Ecological Survey Of The Algae Of Huntington Canyon, Utah, Lorin E. Squires Aug 1972

A Quantitative And Ecological Survey Of The Algae Of Huntington Canyon, Utah, Lorin E. Squires

Theses and Dissertations

A quantitative and ecological study of the algal flora of Huntington Canyon, Emery Co., Utah was conducted from March 1971 to April 1972. Data were collected concerning net plankton, nannoplankton, periphyton and visible attached algae. Certain physical and chemical parameters in the waters of Huntington Creek and a small pond along its course also were measured. The algal flora of Huntington Canyon contains a wide diversity of genera and species. Diatoms are the main constituent of the flora of this stream throughout the year. Hydrurus foetidus is prevalent in the creek in Huntington Canyon from late winter to early summer, …


The Stratigraphy And Economic Potential Of Permo-Pennsylvanian Strata In Southwestern North Dakota, Harold C. Ziebarth Jan 1972

The Stratigraphy And Economic Potential Of Permo-Pennsylvanian Strata In Southwestern North Dakota, Harold C. Ziebarth

Theses and Dissertations

This study of the Fermo-Pennsylvanian Minnelusa Group in North Dakota was designed to clarify the stratigraphy, illustrate association of depositional environments, and to relate the geologic history and economic potential of these strata.

The Minnelusa Group is defined here to include strata above the unconformity on the Madison and Big Snowy Groups and below the Opeche Formation. The Minnelusa Group in North Dakota contains the Tyler, Alaska Bench, Amsden and Broom Creek Formations. The Amsden has been divided into three marker defined lithozones designated, in ascending order, Medora, Dickinson, and Bismarck.

Drill and core samples were examined and described interpretively …


An Analysis Of The Educational Characteristics Of The University Of North Dakota As Perceived By Residents Of Social Fraternities And Residence Halls., Jere Darryl Paddack Jan 1965

An Analysis Of The Educational Characteristics Of The University Of North Dakota As Perceived By Residents Of Social Fraternities And Residence Halls., Jere Darryl Paddack

Theses and Dissertations

No abstract provided.