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Physical Sciences and Mathematics Commons™

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Oceanography and Atmospheric Sciences and Meteorology

Portland State University

2004

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Lower Columbia River Aquatic Nonindigenous Species Survey 2001-2004, Mark Sytsma, Jeffery Cordell, John Chapman, Robyn Draheim Oct 2004

Lower Columbia River Aquatic Nonindigenous Species Survey 2001-2004, Mark Sytsma, Jeffery Cordell, John Chapman, Robyn Draheim

Center for Lakes and Reservoirs Publications and Presentations

Rates of aquatic nonindigenous species (ANS) introductions and their social, economic, and ecological impacts are increasing. Introductions of nonnative marine organisms have increased exponentially over the last two centuries and expenditures on outreach, control, and research exceed millions of dollars per species for several invaders of particular concern to the United States. These trends suggest that major changes are occurring in the freshwater, estuarine, and marine ecosystems of North America, but their magnitude is probably underestimated.

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Report On The Oregon Ballast Water Management Program In 2004, Kiirsten Flynn, Mark Sytsma Sep 2004

Report On The Oregon Ballast Water Management Program In 2004, Kiirsten Flynn, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

This report was prepared for the Oregon legislature pursuant to HB 3620, which was passed during the 2003 session of the Oregon legislature to address management of ballast water discharged from ships. The bill removed sediment from the definition of ballast water, allowed discharge of treated ballast water, created a task force on ballast water management, and required this report. Includes List of Acronyms, charts, graphs and maps.

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Effects Of Experimental Greenhouse Warming On Phytoplankton And Zooplankton Communities In Fishless Alpine Ponds, Angela L. Strecker, Tyler P. Cobb, Rolf D. Vinebrooke Jul 2004

Effects Of Experimental Greenhouse Warming On Phytoplankton And Zooplankton Communities In Fishless Alpine Ponds, Angela L. Strecker, Tyler P. Cobb, Rolf D. Vinebrooke

Environmental Science and Management Faculty Publications and Presentations

The impacts of global warming on aquatic ecosystems are expected to be most pronounced at higher trophic levels in cold-water environments. Therefore, we hypothesized that wanning of fishless alpine ponds would suppress large-bodied consumers (e.g., cladocerans, copepods) and stimulate fast-growing microorganisms (e.g., phytoflagellates, rotifers), thereby altering the community composition and total abundance of zooplankton and phytoplankton. This hypothesis was tested using three blocks of four experimental mesocosms (1000-liter capacity) that were located next to alpine ponds in Banff National Park, Canada. Each block received unfiltered pond water and sediment from a pond following ice out in June 2000. A warming …

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An Integrated Aquatic Vegetation Management Plan For Blue Lake, Fairview, Oregon, Mary Pfauth, Mark Sytsma May 2004

An Integrated Aquatic Vegetation Management Plan For Blue Lake, Fairview, Oregon, Mary Pfauth, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Blue Lake, located in Fairview, is on the 1998 Oregon Department of Environmental Quality (ODEQ) 303(d) list of water quality impaired water bodies for violating the upper pH standard (8.5) and supporting abundant aquatic weeds and alge. The lake is eutrophic and has high algal productivity, especially in mid to late summer. Curlyleaf pondweed, a non-native, invasive aquatic plant species, restricts access to and use of Blue Lake by humans. Human uses of the lake which have been impaired including boating, water skiing, fishing, and swimming. Development of the current Integrated Aquatic Vegetation Management Plan was driven by the need …

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Waldo Lake Research In 2003, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Rich Miller, Laura Johnson, Robert Leslie Annear May 2004

Waldo Lake Research In 2003, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Rich Miller, Laura Johnson, Robert Leslie Annear

Civil and Environmental Engineering Faculty Publications and Presentations

This report summarizes the first year of an effort to develop a more complete understanding of the physical, chemical, and biological characteristics that drive the ecological processes of Waldo Lake. Modern limnology recognizes the importance of watershed processes as well as in- lake processes in lake ecosystem functioning. Therefore, the approach included consideration of watershed hydrology and forcing functions that determine hydrodynamics of the system as well physical and chemical factors that may be important in regulating primary production in the lake. Data collected since 1998 was summarized and bathymetry of the basin was mapped using state-of-the-art digital depth sounding …

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Coastal Lakes Aquatic Plant Survey Report, Mary Pfauth, Mark Sytsma Jan 2004

Coastal Lakes Aquatic Plant Survey Report, Mary Pfauth, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Invasive, non-indigenous plants can degrade water quality and fish habitat when they invade lakes, ponds, and streams. Changes in plant community architecture in lakes due to invasion by canopy-forming invasive aquatic plants can result in loss of native plant biodiversity and reduction of the structural complexity of the underwater habitat. Differences in photosynthetic biochemistry between non-indigenous and native plants can result in large diurnal pH and dissolved oxygen concentrations.

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