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Algal Response To A Thermal Effluent : Study Of A Power Station On The Provo River, Utah, Usa, Lorin E. Squires
Algal Response To A Thermal Effluent : Study Of A Power Station On The Provo River, Utah, Usa, Lorin E. Squires
Theses and Dissertations
The effect of a thermal effluent on the attached algae of the Provo River, Utah, USA, was studied from 1975 to 1977. Data for macroscopic and microscopic algae were collected and analyzed. Diatoms, Cladophora glomerata, and Hydrurus foetidus dominated the flora. The thermal effluent significantly affected the algal flora in a section of river 100 to 135 meters long immediately below the discharge point. Cladophora growth was increased and Hydrurus was absent in this area. In addition, diatom production was often higher and diversity lower than in the rest of the river. Community structure was unique from all other adjacent …
Leaf Litter Processing In Aquatic Systems Two Variable Model, Boyd Jay Hanson
Leaf Litter Processing In Aquatic Systems Two Variable Model, Boyd Jay Hanson
Theses and Dissertations
The adequacy of the negative exponential model with one independent variable, days or accumulated time, as a descriptive equation for aquatic leaf litter processing was examined. The effect of adding a second independent variable, degree days or accumulated temperature, to the model was also examined. The two variable negative exponential model was shown to have at least two advantages over the single variable model. The two variable model adequately fits litter processing data for more cases than the single variable model. The expanded model also allows determination of rate coefficients for various temperature levels of the experiment rather than assuming …
Photosynthetic Fractionation Of Oxygen Isotopes, A Study With Elodea Canadensis, Glen E. Martin
Photosynthetic Fractionation Of Oxygen Isotopes, A Study With Elodea Canadensis, Glen E. Martin
Theses and Dissertations
Bubbles of oxygen from Elodea canadensis were collected and found 5 per mil enriched in 0-18. This confirms the results of both Dole and Vinogradov, who found 0-18 enrichment of photosynthetic oxygen relative to its source, i.e. water. Photosynthesis and respiration appear to have produced the Dole effect, i.e. the 22 per mil 0-18 enrichment of atmospheric oxygen relative to ocean water, its probable source. These results are contrary to findings for both UV photolysis and electrolysis of water both evolving oxygen found depleted in 0-18.
The Plant Communities Of Arches National Park, John Stevens Allan
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
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 …
Ethionine-Resistant Mutants Of The Filamentous Blue-Green Alga Plectonema Boryanum /|Cby Wayne M. Hentsche, Wayne M. Hentschel
Ethionine-Resistant Mutants Of The Filamentous Blue-Green Alga Plectonema Boryanum /|Cby Wayne M. Hentsche, Wayne M. Hentschel
Theses and Dissertations
Ethionine-resistant mutans of Plectonema boryanum have been isolated and partially characterized. The mutant strains exhibit at least 100-fold increase in resistance to L-ethionine. The nature of the change which confers ethionine resistance is not known, but appears to result from the inability of the resistant strains to incorporate ethionine into acid-precipitable material. Initially, ethionine has no effect on the growth rate of the wild-type or the resistant strains, but several hours of exposure to the analog at a concentration greater than 0.5 μg/ml causes a marked inhibition of growth and bleaching in the wild-type cells. The onset of bleaching precedes …
A Revision Of The Herbaceous Members Of The Genus Atriplex (Chenopodiaceae) For The State Of Utah, K. H. Thorne
A Revision Of The Herbaceous Members Of The Genus Atriplex (Chenopodiaceae) For The State Of Utah, K. H. Thorne
Theses and Dissertations
The herbaceous Atriplex species which occur in Utah are revised. This study is based on herbarium specimens and field observations throughout the state. My treatment largely follows that of Rall and Clements (1923). A brief discussion of the history, diagnostic characteristics and phylogeny is given. A descriptive key that includes all taxa has been prepared: type locality, synonyms, general habitat and distribution is reported for each entity. Illustrations and maps are included. One variety is described as new.
Phlox Longifolia Nuttall (Polemoniaceae) Complex Of North America, Frederick J. Peabody
Phlox Longifolia Nuttall (Polemoniaceae) Complex Of North America, Frederick J. Peabody
Theses and Dissertations
Over 1,000 herbarium specimens including 24 type specimens were examined in an attempt to achieve a clearer understanding of the Phlox longifolia complex. Four variables were measured for each specimen and the data were statistically analyzed by disciminant analysis. Using a previously published system of classification for the complex approximately 73% of the measured variation among the specimens was accounted for by that system. The clustering patterns produced in this first analysis indicated that a more conservative approach would be advisable. The formulataion and subsequent application of a modified system produced a grouping of specimens that accounted for 95% of …
Canopy Influence As A Factor In Determining Understory Community Composition, Richard B. Wilcox
Canopy Influence As A Factor In Determining Understory Community Composition, Richard B. Wilcox
Theses and Dissertations
Four tree species (i.e. Pinus ponderosa, Juiperus scopulorum, Quercus Gambelii, and Ceanothus velutinus were chosen for this study. Ten individuals of each species were selected and their associated understory communities and adjacent non-understory communities sampled. Data taken included biotic and abiotic parameters. The data was subjected to similarity index analysis, cluster analysis, discriminant analysis, and x^2 analysis. The results were confirmed by all tests. The forest canopy was shown to directly influence the understory community. The understory community is a shrub-grass dominated type while the non-understory community is an annual-forb dominated type. The different tree species were also shown to …
Environmental Interaction In Summer Algal Communities Of Utah Lake, Mark C. Whiting
Environmental Interaction In Summer Algal Communities Of Utah Lake, Mark C. Whiting
Theses and Dissertations
Utah Lake is a shallow eutrophic lake located in central Utah. It is characterized by high nutrient and silt loads and by large algal blooms in late summer and early fall. Phytoplankton samples and environmental data were taken from June through August 1974. Phytoplankton species were identified and then quantified in a Palmer counting cell. Environmental continuum theory was employed to describe algal succession and regression analysis was used to discover interactions between algal communities and the environment. Phytoplankton communities in June were characterized by high species diversity. As the lake environment became stressed in late summer due to higher …
Certain Edaphic And Biotic Factors Affecting Vegetation In The Shadscale Community Of The Kaiparowits Area, Vane Orlan Campbell
Certain Edaphic And Biotic Factors Affecting Vegetation In The Shadscale Community Of The Kaiparowits Area, Vane Orlan Campbell
Theses and Dissertations
A study area on the southern extensions of the Great Basin cold desert (Kaiparowits Basin, Utah) was selected which has had varying amounts of disturbance. Areas with similar slope and exposure in the Shadscale community were sampled. At each site, soil samples were collected and percent sand, percent clay, percent silt, soluble salts, and hydrogen ion concentrations were measured. Cluster analysis based on percent frequency of the perennial species showed that eight groups or sub-communities were definable within the area sampled. Patterns within the vegetation were shown to be independent with the use of cluster analysis. Discriminant analysis on soil …