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Filtering by: Has journal Ecosystems Remove constraint Has journal: Ecosystems Degree Name Doctor of Philosophy (Ph.D.) Remove constraint Degree Name: Doctor of Philosophy (Ph.D.)

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  • Ecosystem effects of vegetation removal in coastal Oregon Douglas-fir experimental plantations : impacts on ecosystem production, tree growth, nutrients, and soils

    Creator:
    Yildiz, Oktay
    Abstract:
    Effects of partial understory removal on belowground and aboveground ecosystem properties were investigated in 5 and 15 yr old Douglas-fir (Pseudotsuga menziesll (Mirb.) Franco) experimental plantations in western Oregon. Seedling survival was not affected by understory removal at age 5 yr. But through age 15 yr, understory removal increased seedling...
    Resource Type:
    Dissertation
    Full Text:
    of Doctor of Philosophy in Forest Science presented on July 20, 2000. Title: Ecosystem Effects of

  • Ecosystem Photosynthesis and Forest-Atmosphere Interactions Inferred from Carbonyl Sulfide

    Creator:
    Rastogi, Bharat
    Abstract:
    An increase in anthropogenic activities since the industrial revolution, primarily due to burning of fossil fuels and changes in land cover, has resulted in a steady increase in the global mean atmospheric CO2 concentrations. While there is unequivocal scientific evidence on global warming and its multidimensional impacts on natural and...
    Resource Type:
    Dissertation
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    Forest Ecosystems and Society presented on May 8, 2018. Title: Ecosystem Photosynthesis and

  • Integrating solute transport, metabolism and processing in stream ecosystems

    Creator:
    González Pinzón, Ricardo A.
    Abstract:
    After three decades of active research coupling hydrology and stream ecology, the connection among solute transport, metabolism and processing is still unresolved. These knowledge gaps obscure the functioning of stream ecosystems and how those ecosystems interact with other landscape processes. We must resolve these challenges to wisely manage water resources,...
    Resource Type:
    Dissertation
    Full Text:
    in stream ecosystems AN ABSTRACT OF THE DISSERTATION OF Ricardo A. González

  • Bioactive Microbial Natural Products from Unique Indonesian Black Water Ecosystems

    Creator:
    Sheng, Yan
    Abstract:
    The discovery of new antibiotics reached its peak during the golden era of antibiotics in the mid 20th century and continued to thrive until the 1980s. However, after more than 50 years of fruitful exploration and exploitation of microbial natural products the discovery rate of new antibiotics has dropped drastically...
    Resource Type:
    Dissertation
    Full Text:
    Title: Bioactive Microbial Natural Products from Unique Indonesian Black Water Ecosystems

  • Cryptogam communities in forest and steppe ecosystems of Oregon, USA

    Creator:
    Root, Heather T.
    Abstract:
    I focus on addressing knowledge gaps relating to management of cryptogams in Oregon's public lands in Pseudotsuga menziesii-Tsuga heterophylla forests on the west side of the Cascade Range and dryland steppe in the Cascade Range's rainshadow. While a great deal of research has illustrated the importance of late-successional forests for...
    Resource Type:
    Dissertation
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    presented on June 9, 2011. Title: Cryptogam Communities in Forest and Steppe Ecosystems of Oregon, USA

  • Trophic cascades and large mammals in the Yellowstone ecosystem

    Creator:
    Painter, Luke E.
    Abstract:
    Reintroduction of wolves to Yellowstone National Park (YNP) in 1995-96 provided a rare opportunity to observe the response of an ecosystem to the return of a top predator, including possible reversal of decades of decline of aspen, cottonwood, and tall willows suppressed by intensive herbivory on elk winter ranges. To...
    Resource Type:
    Dissertation
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    ecosystem _____________________________________________________________________ AN ABSTRACT OF THE

  • Application of nonequilibrium ecology to managed riparian ecosystems

    Creator:
    Stringham, Tamzen K.
    Abstract:
    Seasonal trends in water table level and soil moisture for four plant community types within an irrigated eastern Oregon riparian zone were described. Aboveground biomass, species composition, litter, percent bareground and percent basal cover of key plant species and life forms were measured. The relationship between water table levels and...
    Resource Type:
    Dissertation
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    ecosystems AN ABSTRACT OF THE THESIS OF Tamzen K. Stringham for the degree of Doctor of Philosophy in

  • Small mammal micro- and macrohabitat selection in streamside ecosystems

    Creator:
    Doyle, Arlene T.
    Abstract:
    During summer and fall of 1981 to 1983, mark-recapture was conducted in riparian and upland habitats within old-growth and mature forests in the Cascade Range of Oregon. Number of individuals and species richness were greater in riparian than upland habitat. For most species, the mean adult weights and the percentages...
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    Dissertation
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    streamside ecosystems AN ABSTRACT OF THE THESIS OF Arlene T. Doyle for the degree of Doctor of Philosophy

  • The role of ectomycorrhizal fungi in ecosystem recovery

    Creator:
    Amaranthus, Michael P.
    Abstract:
    The effect of the abundance and rapidity of ectomycorrhiza and root tip formation on conifer seedling survival and growth was investigated on disturbed forest sites in southwest Oregon and northern California. Experiments were conducted over a range of community types and environmental conditions. A range of sources of transfer soil...
    Resource Type:
    Dissertation

  • Coastal Dunes as Meta-Ecosystems: Connecting Marine Subsidies to Dune Ecosystem Functions on the U.S. Pacific Northwest Coast

    Creator:
    Constant, Vanessa
    Abstract:
    Ecological communities are connected in space and time through the transfer of energy, materials, and organisms, together known as ecological subsidies. These ecological subsidies can have substantial effects on community structure, function, and services, especially when the connections are between communities with contrasting productivity. At the ocean-land interface, low productivity...
    Resource Type:
    Dissertation
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    -Ecosystems: Connecting Marine Subsidies to Dune Ecosystem Functions on the U.S. Pacific Northwest Coast