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Environmental Sciences

1999

Portland State University

Articles 1 - 9 of 9

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Human History As A Natural Science. Review Of: Guns, Germs, And Steel: The Fates Of Human Societies By Jared Diamond, Robert Costanza Oct 1999

Human History As A Natural Science. Review Of: Guns, Germs, And Steel: The Fates Of Human Societies By Jared Diamond, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Book review of Guns, Germs, and Steel: The Fates of Human Societies. Jared Diamond. W. W. Norton, New York, 1997.


Modeling Macrophytes Of The Columbia Slough, Oregon, Chris Berger, Scott A. Wells Aug 1999

Modeling Macrophytes Of The Columbia Slough, Oregon, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The Columbia Slough is a tidally influenced freshwater system of wetlands, channels, and lakes located within the Portland, Oregon metropolitan area at the confluence of the Willamette and Columbia Rivers. It is a eutrophic water body susceptible to algae blooms and crashes and periods of high pH which violate water quality standards. High nutrient loads from groundwater principally controls algae productivity. Past structural changes to the Columbia Slough have included filling of wetlands and lakes and the construction of levees, dikes, culverts and irrigation channels. These changes have altered the natural flow dynamics creating an environment more conducive to eutrophication. …


One Giant Leap. Review Of: Consilience: The Unity Of Knowledge By Edward O. Wilson, Robert Costanza Jun 1999

One Giant Leap. Review Of: Consilience: The Unity Of Knowledge By Edward O. Wilson, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Book review of Consilience: The Unity of Knowledge. Edward O. Wilson. Knopf, New York, 1998.


Measurement Of Free Radicals Oh And Ho₂ In Los Angeles Smog, Linda Acha George, Thomas M. Hard, Robert J. O'Brien May 1999

Measurement Of Free Radicals Oh And Ho₂ In Los Angeles Smog, Linda Acha George, Thomas M. Hard, Robert J. O'Brien

Environmental Science and Management Faculty Publications and Presentations

Atmospheric free radicals hydroxyl and hydroperoxyl (OH and HO₂, collectively HOᵪ ) are the catalysts that cause secondary or photochemical air pollution. Chemical mechanisms for oxidant and acid formation, on which expensive air pollution control strategies are based, must accurately predict these radical concentrations. We have used the fluorescence assay with gas expansion (FAGE) technique to carry out the first simultaneous, in situ measurements of these two radicals in highly polluted air during the Los Angeles Free Radical Experiment. A complete suite of ancillary measurements was also made, including speciated hydrocarbons, carbon monoxide, aldehydes, nitric oxide, nitrogen dioxide, and ozone …


Globalization And The Sustainability Of Human Health: An Ecological Perspective, Robert Costanza, A. J. Mcmichael, Bert Bolin, Gretchen C. Daily, Carl Folke, Kerstin Lindahl-Kiessling, Elisabet Lindgren, Bo Niklasson Mar 1999

Globalization And The Sustainability Of Human Health: An Ecological Perspective, Robert Costanza, A. J. Mcmichael, Bert Bolin, Gretchen C. Daily, Carl Folke, Kerstin Lindahl-Kiessling, Elisabet Lindgren, Bo Niklasson

Institute for Sustainable Solutions Publications and Presentations

The last half-century has seen momentous and accelerating changes in humankind's economic activities, political relations, and social and demographic profile. A prominent feature of this change is the increasing scale of human impact on Earth's natural biophysical systems: the climate system, stratospheric ozone, biodiversity, terrestrial and marine food-producing ecosystems, and the great cycles of water, nitrogen, and sulfur (Meyer 1996, Vitousek et al. 1997). These systems sustain the conditions on which life depends, and their weakening may therefore have profound long-term implications for human population health (McMichael 1993, Last 1997).


Four Visions Of The Century Ahead: Will It Be Star Trek, Ecotopia, Big Government Or Mad Max?, Robert Costanza Feb 1999

Four Visions Of The Century Ahead: Will It Be Star Trek, Ecotopia, Big Government Or Mad Max?, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Lays out different visions as to what the 21st century will be like. Where these visions are based; Default technological optimist vision; Technological skeptic's nightmare; War between public interest and private enterprise; Low-consumption sustainable vision; How society should decide among the visions; Challenges.


Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips Feb 1999

Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips

Environmental Science and Management Faculty Publications and Presentations

Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative buds with thermocouple probes and compared temperatures of normal buds and abnormal buds with loosened, rosetted outer scales in elevated temperature chambers. The abnormal buds had higher and earlier peak daily temperatures than normal buds. Elevated temperature may influence the internal temperature of buds and contribute to the development of abnormal, rosetted buds with loosened outer scales. Abnormal bud development may alter branching patterns and allometry of Douglas-fir trees subjected to climatic change.


The Effects Of Urbanization And Human Disturbance Upon Plant Community Structure And Bird Species Richness, Diversity, And Abundance In A Natural Forested Area (Forest Park) In Portland, Oregon, Nancy Ellen Broshot Jan 1999

The Effects Of Urbanization And Human Disturbance Upon Plant Community Structure And Bird Species Richness, Diversity, And Abundance In A Natural Forested Area (Forest Park) In Portland, Oregon, Nancy Ellen Broshot

Dissertations and Theses

The effects of urbanization and continual human disturbance on the plant and avian communities of Forest Park and forested lands surrounding Portland, Oregon, were studied. I examined characteristics of plant and avian communities at 25 sites, 24 which were in Forest Park and surrounding areas and one which was in the Ancient Forest Preserve (old-growth stand) northwest of Forest Park. Data were analyzed using multiple regression, ANOV A, and Bonferonni/Dunn. Seven variables were selected representing different urbanization gradients. An additional covariable coded for the old-growth stand, allowing it to be used as a control.

Many tree variables, especially those related …


Analytical Modeling Of Cake Filtration, Scott A. Wells Jan 1999

Analytical Modeling Of Cake Filtration, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The specific resistance model of cake filtration is based on the assumption that the average cake resistance is constant over time. This implies also that the spatially average values of porosity and pressure differential are also constant over time since specific resistance is a function of both parameters.

An analytical cake filtration model based on Tiller (1975) was derived using constitutive properties of kaolin suspensions in distilled water. Constitutive properties were determined by experiments performed using high-energy X-rays and porewater pressure probes to determine the spatial and temporal distributions of porosity and porewater pressure. Using these constitutive properties, predictions were …