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Full-Text Articles in Physical Sciences and Mathematics

Using Transects To Understand Cyanobacterial Blooms, John Rueter Nov 2016

Using Transects To Understand Cyanobacterial Blooms, John Rueter

Environmental Science and Management Faculty Publications and Presentations

Presentation focuses on Toxic algae (and cyanobacteria) and on short-term mitigation:

  • Monitoring
  • Possible approaches


Understanding The Links Between Cyanobacteria Physiology And Hydrodynamics May Help Find Adaption Strategies For Toxic Blooms, John Rueter Oct 2016

Understanding The Links Between Cyanobacteria Physiology And Hydrodynamics May Help Find Adaption Strategies For Toxic Blooms, John Rueter

Environmental Science and Management Faculty Publications and Presentations

Even though we are managing lakes to decrease algal blooms overall, harmful algal blooms seem to be showing up more and more frequently. Although the word “blooms” connotes dominance and rapid growth, dangerous accumulations of cyanobacteria can occur because of combinations of physiological advantages and particular weather and hydrodynamic conditions. I am particularly interested in specific conditions that might favor Aphanizomenon versus those that might favor Microcystis in Upper Klamath and Agency Lakes. Aphanizomenon is a nuisance and large blooms can lead to oxygen depletion and fish deaths. Microcystis can both be a nuisance and is toxic. The comparison of …


How 5-Day Weather Patterns And Buoyancy Regulation Impact Algal Community Assemblage, Roberta Brunkalla May 2016

How 5-Day Weather Patterns And Buoyancy Regulation Impact Algal Community Assemblage, Roberta Brunkalla

Student Research Symposium

The purpose of this study is to model how 5-day weather patterns and algal buoyancy regulation influence the competition between two bloom forming cyanobacteria species in Upper Klamath Lake, Oregon. Sudden changes in weather patterns can quickly impact lake thermal structure, which can rapidly influence the competition between buoyancy regulating cyanobacteria. By modeling competition, I hope to address how altered climate would shift the competitive advantage to toxin forming cyanobacteria. I plan on accomplishing this by coupling a one-dimensional hydrodynamic and algal competition model, with lake specific physiological parameters. A sensitivity test of the model could reveal dramatic shifts in …


Historical And Existing Vascular And Bryophyte Flora, Former Blue Heron Paper Mill, Willamette Falls, Oregon City, Oregon, John A. Christy, Philip Gaddis Aug 2015

Historical And Existing Vascular And Bryophyte Flora, Former Blue Heron Paper Mill, Willamette Falls, Oregon City, Oregon, John A. Christy, Philip Gaddis

Institute for Natural Resources Publications

Willamette Falls has long been a focus of botanical interest, but industrial development at the site has limited public access for over a century. The closure of the Blue Heron paper mill on the south bank of the river, and proposed redevelopment of the site, has given planners an opportunity to revisit this part of the falls and identify its current flora. As part of the preconstruction planning process for public access to the falls, Metro contracted John Christy to document the historical and existing vascular flora on the site, and Philip Gaddis joined us to document the bryophyte flora. …


History, Current Conditions, And Wetland Restoration At Killin Wetlands Natural Area, Washington County, Oregon, John A. Christy Jan 2015

History, Current Conditions, And Wetland Restoration At Killin Wetlands Natural Area, Washington County, Oregon, John A. Christy

Institute for Natural Resources Publications

In September 2014, the Metro Natural Area Program engaged The Wetland Conservancy to develop a scientific assessment of Metro’s 590-acre Killin Wetlands Natural Area. Metro acquired the lands comprising the KWNA between 2000 and 2012 with funds from two voterapproved open space bond measures. Since 2000, Metro has sought to advance natural area restoration at the site, focusing on the suppression of non-native pasture weeds and planting of native trees and shrubs in higher parts of the floodplain and its edges. Most uplands in Metro ownership have been maintained in agriculture through leased partnerships with local farmers.

Metro and its …


2014 Aquatic Weed Surveys In Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, And Estacada Lake, Rich Miller, Mark D. Sytsma, Jeffrey Thomas Brittain Dec 2014

2014 Aquatic Weed Surveys In Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, And Estacada Lake, Rich Miller, Mark D. Sytsma, Jeffrey Thomas Brittain

Center for Lakes and Reservoirs Publications and Presentations

The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included in the Project include Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake. The operator of the Project, Portland General Electric (PGE), was issued a license on December 21, 2010 by the Federal Energy Regulatory Commission (FERC) for continued operations and maintenance. The Final Environmental Impact Statement (FEIS) for the license noted that regular surveys for invasive aquatic weed species would be conducted as part …


Physical, Chemical And Biological Assessment Of Yoncalla Log Ponds, Rich Miller, Mark D. Sytsma, Angela L. Strecker Nov 2014

Physical, Chemical And Biological Assessment Of Yoncalla Log Ponds, Rich Miller, Mark D. Sytsma, Angela L. Strecker

Center for Lakes and Reservoirs Publications and Presentations

The Yoncalla Log Ponds are a series of four ponds located in within the city limits of the town in Yoncalla in northern Douglas County, Oregon. The ponds were created in stages between the late 1930s and the 1950s and used for log storage through the 1970s (North Douglas Betterment 2014). North Douglas Betterment purchased the land surrounding the ponds and contracted with the Center for Lakes and Reservoirs at Portland State University to assess the current morphometry, vegetation and water quality status of the ponds and provide recommendations for management of the aquatic vegetation. The scope of this document …


Osmb Final Report, Task 4: Oregon Lake Watch, Angela L. Strecker, Rich Miller, Vanessa Morgan Apr 2014

Osmb Final Report, Task 4: Oregon Lake Watch, Angela L. Strecker, Rich Miller, Vanessa Morgan

Center for Lakes and Reservoirs Publications and Presentations

The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species (AIS), provide early detection of AIS invasions, and provide long term water quality data for the better management of Oregon’s lakes and reservoirs. Protocols were created for citizen scientists to survey for AIS, collect temperature and water clarity data, and record the data through an online data entry portal. An OLW website was developed to educate about AIS and provide survey protocols and identification materials to volunteers. AIS surveys …


Aquatic Invasive Species Surveys Of Eastern Oregon Waterbodies In 2013 And 2014, Rich Miller, Mark D. Sytsma Feb 2014

Aquatic Invasive Species Surveys Of Eastern Oregon Waterbodies In 2013 And 2014, Rich Miller, Mark D. Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Early detection aquatic invasive species (AIS) surveys were conducted at 33 Eastern Oregon waterbodies during the summers of 2013 and 2014. Submerged aquatic plants, gastropods, bivalves, and crayfish were collected using a thatch rake, benthic dredge, plankton net, and modified minnow traps. Shoreline aquatic noxious weeds were noted when present and water quality characteristics were measured. Two AIS snail species, one AIS crayfish species, and five AIS plant species were detected during the surveys. Big-ear radix snails (Radix auricularia) were newly detected at 14 waterbodies distributed across the survey area. Chinese mystery snails (Cipangopaludina chinensis) were …


Oregon Dreissenid Mussel: Rapid Response Plan, Robyn Draheim, Rick Boatner, Glenn Dolphin, Lisa Debruyckere Oct 2013

Oregon Dreissenid Mussel: Rapid Response Plan, Robyn Draheim, Rick Boatner, Glenn Dolphin, Lisa Debruyckere

Center for Lakes and Reservoirs Publications and Presentations

In 2007, both zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis) were found to have established populations west of the Rocky Mountains. The risk posed to the Pacific Northwest by the proximity of these new infestations is significant. This plan was developed in response to the increasing likelihood of the successful transport and introduction of these species into the State of Oregon and Pacific Northwest. Although prevention remains the most cost-effective means of addressing potential infestations of aquatic invasive species, if prevention efforts fail, the State of Oregon must be prepared to respond rapidly …


Aquatic Invasive Plant Surveys In The Blm Medford District During 2012, Rich Miller, Vanessa Morgan, Mark D. Sytsma Apr 2013

Aquatic Invasive Plant Surveys In The Blm Medford District During 2012, Rich Miller, Vanessa Morgan, Mark D. Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Aquatic plant surveys were conducted at 22 waterbodies located within the Bureau of Land Management’s Medford District during the summer of 2012. Sites included eleven lakes, ponds or reservoirs and six reaches along the Rogue and Applegate Rivers. Five sampling areas surveyed during 2010 and 2011 were revisited to determine the extent of known non-native species infestations, positively identify rare species, or verify the absence of an expected non-native species. Plant specimens were collected at up to 50 sites at each waterbody using plant rakes or by observation. The non-native submersed species curly leaf pondweed (Potamogeton crispus) and …


Aquatic Invasive Species Surveys Of Upper Klamath Lake, Fourmile Lake, And Lake Of The Woods, Or During 2012, Rich Miller, Mark D. Sytsma Mar 2013

Aquatic Invasive Species Surveys Of Upper Klamath Lake, Fourmile Lake, And Lake Of The Woods, Or During 2012, Rich Miller, Mark D. Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were collected using plant rakes, benthic dredges, plankton nets, and crayfish traps. No invasive aquatic plants, gastropods, snails, bivalves or crayfish were detected in the lakes.


Survey Of Aquatic Invasive Species In Selected Umpqua National Forest Lakes And Ponds, Mark D. Sytsma, Rich Miller Jan 2012

Survey Of Aquatic Invasive Species In Selected Umpqua National Forest Lakes And Ponds, Mark D. Sytsma, Rich Miller

Center for Lakes and Reservoirs Publications and Presentations

Eleven lakes and ponds within the Umpqua National Forest were surveyed for invasive aquatic macrophytes, snails, bivalves, and crayfish during the summer of 2011. Yellow floating heart (Nymphoides peltata), an invasive floating leaf macrophyte species, was detected in Willow Sump within the Little River drainage. European ear snails (Radix auricularia), an invasive species present in several Umpqua National Forest waterbodies, were detected in Beaver Pond within the Steamboat Creek drainage. One native crayfish species, the signal crayfish (Pacifastacus leniusculus), was observed in Crayfish Lake within the Brice Creek drainage. Diverse assemblages of native plant species were observed in the lakes …


Aquatic Plant Surveys In The Bureau Of Land Management, Medford District, 2010-2011, Mark D. Sytsma, Rich Miller, Vanessa Morgan Dec 2011

Aquatic Plant Surveys In The Bureau Of Land Management, Medford District, 2010-2011, Mark D. Sytsma, Rich Miller, Vanessa Morgan

Center for Lakes and Reservoirs Publications and Presentations

The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011).

Several IAPS classified as noxious have been detected within …


Hydroacoustic Survey And Point Sampling Of Macrophytes In Diamond Lake 2009, Joseph Eilers, Benn Eilers, Mark D. Sytsma, Rich Miller Jan 2010

Hydroacoustic Survey And Point Sampling Of Macrophytes In Diamond Lake 2009, Joseph Eilers, Benn Eilers, Mark D. Sytsma, Rich Miller

Center for Lakes and Reservoirs Publications and Presentations

MaxDepth Aquatics, Inc. was contracted to conduct a hydroacoustic survey of macrophyte distribution in Diamond Lake in 2009. The survey essentially repeated surveys conducted in 2002 and 2007, allowing for a detailed assessment of conditions in 2009 and comparisons among previous years. In addition, Portland State University was contracted to conduct a depth stratified random point sample survey of macrophyte species presence and absence. The point sample survey was similar to surveys conducted in 2005 and 2007. The results of the 2009 hydroacoustic survey showed that macrophytes were widely distributed throughout the lake at depths less than 8 meters, although …


2005 Diamond Lake Submersed Aquatic Vegetation Survey, Mark D. Sytsma, Mary Pfauth Jan 2006

2005 Diamond Lake Submersed Aquatic Vegetation Survey, Mark D. Sytsma, Mary Pfauth

Center for Lakes and Reservoirs Publications and Presentations

Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern Cascade Mountains of Oregon, at an elevation of over 5000 feet (>1524 meters). Diamond Lake is a high-use waterbody that supports angling, public campgrounds, recreational boating, swimming, and water skiing. The human activity associated with the lake has been a significant contributor to the economy of southern Oregon since the early part of the twentieth century.

Historically Diamond Lake was fishless but …


Survey Of Aquatic Plants In Corps Of Engineers Reservoirs, Kimberly D. Walker, Mark D. Sytsma Jan 2000

Survey Of Aquatic Plants In Corps Of Engineers Reservoirs, Kimberly D. Walker, Mark D. Sytsma

Center for Lakes and Reservoirs Publications and Presentations

A survey of aquatic plants in a selected Corps of Engineers reservoirs in Oregon was conducted. Cottage Grove, Dorena, Fern Ridge, Dexter and Willow Creek Reservoirs contained abundant aquatic plants. Potamogeton pectinatus and Potamogeton epihydrous were the most common native plant species. Myriophyllum aquaticum and Potamogeton crispus were the most widespread nonnative plants. Species richness in the reservoirs was correlated with trophic status and basin morphology. Shallow reservoirs that included extensive areas of nutrient-rich sediments that were historic flood plain soils supported the greatest biomass and number of species. Mesotrophic reservoirs had lower species diversity. Oligotrophic reservoirs with steep basin …