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Filtering by: Creator Butler, Barbara A. Remove constraint Creator: Butler, Barbara A. Academic Affiliation Crop and Soil Science Remove constraint Academic Affiliation: Crop and Soil Science Advisor Myrold, David D. Remove constraint Advisor: Myrold, David D.

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  • Microbial community dynamics associated with rhizosphere carbon flow

    Creator:
    Butler, Jessica L.
    Abstract:
    The cycling of root-deposited photo synthate (rhizodeposition) through the soil microbial biomass is widely recognized as a critical component of ecosystem functioning. Little is currently known about the flow of photosynthate through the microbial biomass however. My research goal was to examine if and how the flow of root-deposited photo...
    Resource Type:
    Masters Thesis
    Full Text:
    ASSOCIATED WITH RHIZOSPHERE CARBON FLOW by Jessica L. Butler A THESIS submitted to Oregon State

  • The link between nitrogen cycling and soil microbial community composition in forest soils of western Oregon

    Creator:
    Boyle, Stephanie A.
    Abstract:
    The objectives of this thesis were to examine the links between soil microbial community composition and function using the nitrogen (N) cycle as a model for these interactions and to assess the impact of environmental factors such as microclimate, vegetation type, and nutrient availability on microbial diversity and N transformations...
    Resource Type:
    Dissertation
    Full Text:
    Stephanie A. Boyle for the degree of Doctor of Philosophy in Soil Science presented on March 15, 2007

  • Using Algal Biomass as a Fertilizer

    Creator:
    Cappellazzi, Shannon B.
    Abstract:
    Algae can be used in a variety of wastewater systems to capture nutrients while fixing carbon dioxide from the atmosphere. I conducted field trials at three locations in Oregon with both corn and potato crops to assess the agronomic value and environmental impact of using the resulting algal biomass as...
    Resource Type:
    Dissertation
    Full Text:
    : Using Algal Biomass as a Fertilizer Abstract approved

  • Carbon cycling and priming of soil organic matter decomposition in a forest soil following glucose additions

    Creator:
    Diaz, David D.
    Abstract:
    Soils are a globally significant carbon (C) pool and have the potential to respond to elevated CO2 and environmental changes through positive feedback cycles that enhance the turnover of soil organic matter (SOM). Understanding the mechanisms governing the turnover of SOM is particularly important for modeling the fate of C...
    Resource Type:
    Masters Thesis
    Full Text:
    May 1, 2008. Title: Carbon Cycling and Priming of Soil Organic Matter Decomposition in a Forest

  • Diversity and Activity of Microbial Extracellular Peptidases in Soil

    Creator:
    Nguyen, Trang T. H.
    Abstract:
    Soil nitrogen exists largely as organic matter, including plant liter, dead animal matter, and microbial necromass. About 90% of soil organic nitrogen is proteinaceous material that is too large for plants and microorganisms to assimilate directly. Protein depolymerization therefore plays a critical role in mobilizing this organic source of nitrogen,...
    Resource Type:
    Dissertation
    Full Text:
    therefore plays a critical role in mobilizing this organic source of nitrogen, producing lower molecular

  • The genetic diversity of Ceanothus-infective Frankia

    Creator:
    Ritchie, Nancy J.
    Abstract:
    Frankia from root nodules of nine different species of Ceanothus were characterized. DNA was amplified directly from nodular material using the polymerase chain reaction (PCR). The amplified region includes the 3' end of the 16S rRNA gene, the intergenic spacer (IGS), and a large portion of the 23S rRNA gene....
    Resource Type:
    Masters Thesis
    Full Text:
    amplified region includes the 3' end of the 16S rRNA gene, the intergenic spacer (IGS), and a large portion

  • Detection of the Burkholderia cepacia complex in soil environments

    Creator:
    Miller, Suzanne C. McKenzie
    Abstract:
    Burkholderia cepacia complex (Bcc) bacteria reside in soil, plant rhizospheres, and water, but the prevalence of Bcc in outdoor environments is not clear. In this study, we sampled a variety of soil and rhizosphere environments with which people may have contact: playgrounds, athletic fields, parks, hiking trails, residential yards and...
    Resource Type:
    Masters Thesis
    Full Text:
    of Bcc in outdoor environments is not clear. In this study, we sampled a variety of soil and

  • Variation in communities of ammonia-oxidizing and denitrifying bacteria in Fennoscandian boreal forest soils

    Creator:
    Ghimire, Rama D.
    Abstract:
    The objective of this study was to examine the variation among ammonia-oxidizing and denitrifying communities in soils of a natural Fennoscandian boreal forest and of a forest with a long history of fertilization with different levels of nitrogen (N), and to examine whether there are any changes in the microbial...
    Resource Type:
    Masters Thesis
    Full Text:
    variation among ammonia-oxidizing and denitrifying communities in soils of a natural Fennoscandian boreal

  • Litter controls of microbial community composition and function in forest soils

    Creator:
    Brant, Justin B.
    Abstract:
    Most carbon (C) transformations in soil are carried out by a diverse and complex soil microbial community. The size and composition of the soil microbial community is determined by poorly understood interactions between the quantity and chemical composition of plant inputs, as well as climate. Given the metabolic diversity of...
    Resource Type:
    Masters Thesis
    Full Text:
    by a diverse and complex soil microbial community. The size and composition of the soil microbial

  • Response of soil microbial communities and nitrogen cycling processes to changes in vegetation inputs

    Creator:
    Brewer, Elizabeth Ann
    Abstract:
    Changes in the type and amount of plant inputs can occur gradually, as with succession, or rapidly, as with harvesting or wildfire. With global change it is anticipated that both gradual and immediate scenarios will occur at increasing frequency. Changes in vegetation inputs alter the quality and quantity of soil...
    Resource Type:
    Dissertation
    Full Text:
    -term organic matter manipulations were found to affect microbial C and N cycling, but to a lesser