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• 1. [Article] Emergent thermodynamics in a system of macroscopic, chaotic surface waves

  The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, ...

  Citation × Citation Citation Abstract Copy Title: Emergent thermodynamics in a system of macroscopic, chaotic surface waves Author: Welch, Kyle Year: 2016 The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, I have contstructed and characterized a two-dimensional metafluid, so-called because its constitutive dynamics are derived not from atoms and molecules but from macroscopic, chaotic surface waves excited on a vertically agitated fluid. Unlike in conventional fluids, the viscosity and temperature of this metafluid are independantly tunable. Despite this unconventional property, our system is surprisingly consistent with equilibrium thermodynamics, despite being constructed from macroscopic, non-equilibrium elements. As a programmable material, our metafluid represents a new platform on which to study complex phenomena such as self-assembly and pattern formation. We demonstrate one such application in our study of short-chain polymer analogs embedded in our system. Title: Emergent thermodynamics in a system of macroscopic, chaotic surface waves Author: Welch, Kyle Year: 2016 The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, I have contstructed and characterized a two-dimensional metafluid, so-called because its constitutive dynamics are derived not from atoms and molecules but from macroscopic, chaotic surface waves excited on a vertically agitated fluid. Unlike in conventional fluids, the viscosity and temperature of this metafluid are independantly tunable. Despite this unconventional property, our system is surprisingly consistent with equilibrium thermodynamics, despite being constructed from macroscopic, non-equilibrium elements. As a programmable material, our metafluid represents a new platform on which to study complex phenomena such as self-assembly and pattern formation. We demonstrate one such application in our study of short-chain polymer analogs embedded in our system. Close

• 2. [Article] Review of Estimates of ground-water recharge, base flow, and stream reach gains and losses in the Willamette River Basin, Oregon

  1 p. Review produced for HC 441: Science Colloquium: Willamette River Environmental Health, Robert D. Clark Honors College, University of Oregon, Spring term, 2004.

  Citation × Citation Citation Abstract Copy Title: Review of Estimates of ground-water recharge, base flow, and stream reach gains and losses in the Willamette River Basin, Oregon Author: Gordon, Eleanor, Lee, Karl K., Risley, John C., Geological Survey (U.S.) Year: 2006, 2004 1 p. Review produced for HC 441: Science Colloquium: Willamette River Environmental Health, Robert D. Clark Honors College, University of Oregon, Spring term, 2004. Title: Review of Estimates of ground-water recharge, base flow, and stream reach gains and losses in the Willamette River Basin, Oregon Author: Gordon, Eleanor, Lee, Karl K., Risley, John C., Geological Survey (U.S.) Year: 2006, 2004 1 p. Review produced for HC 441: Science Colloquium: Willamette River Environmental Health, Robert D. Clark Honors College, University of Oregon, Spring term, 2004. Close

• 3. [Article] MORPHOLOGICAL VARIATION OF PISASTER OCHRACEUS IN RESPONSE TO WAVE EXPOSURE

  52 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2...

  Citation × Citation Citation Abstract Copy Title: MORPHOLOGICAL VARIATION OF PISASTER OCHRACEUS IN RESPONSE TO WAVE EXPOSURE Author: Bjorkquist, Alyssa Year: 2016 52 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Title: MORPHOLOGICAL VARIATION OF PISASTER OCHRACEUS IN RESPONSE TO WAVE EXPOSURE Author: Bjorkquist, Alyssa Year: 2016 52 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Close

• 4. [Article] Trout Creek swamp restoration environmental assessment

  51 pp. Map, table, references. The swamp is located about 10 miles west of Sisters, in Deschutes County, Oregon, on the Sisters Ranger District of the Deschutes National Forest (Figure 1). The swamp is ...

  Citation × Citation Citation Abstract Copy Title: Trout Creek swamp restoration environmental assessment Author: Sisters Ranger District (Or.) Year: 2008, 2002 51 pp. Map, table, references. The swamp is located about 10 miles west of Sisters, in Deschutes County, Oregon, on the Sisters Ranger District of the Deschutes National Forest (Figure 1). The swamp is just south of Whispering Pines Campground, at the junction of Forest Roads 1018 and 1520. Captured May 25, 2007. Title: Trout Creek swamp restoration environmental assessment Author: Sisters Ranger District (Or.) Year: 2008, 2002 51 pp. Map, table, references. The swamp is located about 10 miles west of Sisters, in Deschutes County, Oregon, on the Sisters Ranger District of the Deschutes National Forest (Figure 1). The swamp is just south of Whispering Pines Campground, at the junction of Forest Roads 1018 and 1520. Captured May 25, 2007. Close

• 5. [Article] Trout Creek swamp restoration decision notice and finding of no significant impact

  7 pp. Map. The swamp is located about 10 miles west of Sisters, in Deschutes County, Oregon, on the Sisters Ranger District of the Deschutes National Forest (Figure 1). The swamp is just south of Whispering ...

  Citation × Citation Citation Abstract Copy Title: Trout Creek swamp restoration decision notice and finding of no significant impact Author: Sisters Ranger District (Or.) Year: 2008, 2002 7 pp. Map. The swamp is located about 10 miles west of Sisters, in Deschutes County, Oregon, on the Sisters Ranger District of the Deschutes National Forest (Figure 1). The swamp is just south of Whispering Pines Campground, at the junction of Forest Roads 1018 and 1520. Captured May 25, 2007. Title: Trout Creek swamp restoration decision notice and finding of no significant impact Author: Sisters Ranger District (Or.) Year: 2008, 2002 7 pp. Map. The swamp is located about 10 miles west of Sisters, in Deschutes County, Oregon, on the Sisters Ranger District of the Deschutes National Forest (Figure 1). The swamp is just south of Whispering Pines Campground, at the junction of Forest Roads 1018 and 1520. Captured May 25, 2007. Close

• 6. [Article] A Model of Basal Hydrologic Networks and Effective Stress Beneath an Ice Sheet

  Subglacial processes that control the water pressure and flow determine the large-scale behavior of the overlying ice by regulating basal resistance. We implement a model in which a steady-state subglacial ...

  Citation × Citation Citation Abstract Copy Title: A Model of Basal Hydrologic Networks and Effective Stress Beneath an Ice Sheet Author: Papamarcos, Sara Year: 2012 Subglacial processes that control the water pressure and flow determine the large-scale behavior of the overlying ice by regulating basal resistance. We implement a model in which a steady-state subglacial conduit system is surrounded by fully saturated porous media. We investigate branching in this system at fixed angles of 15 degrees, 30 degrees and 45 degrees to the direction of ice flow and further assess these systems by calculating the hydraulic potential gradient to determine conduit flow path. We solve our governing equations for porous media flow and allow ice infiltration of the pore space to occur at a critical effective stress N infiltration. For low values of N infiltration, ice infiltration of sediment allows these conduits to follow their original paths. Where insufficient ice infiltration occurs, the conduit path instead lies parallel to the direction of ice flow. Our results speak to the importance of incorporating small-scale processes into models of subglacial hydrologic networks. Title: A Model of Basal Hydrologic Networks and Effective Stress Beneath an Ice Sheet Author: Papamarcos, Sara Year: 2012 Subglacial processes that control the water pressure and flow determine the large-scale behavior of the overlying ice by regulating basal resistance. We implement a model in which a steady-state subglacial conduit system is surrounded by fully saturated porous media. We investigate branching in this system at fixed angles of 15 degrees, 30 degrees and 45 degrees to the direction of ice flow and further assess these systems by calculating the hydraulic potential gradient to determine conduit flow path. We solve our governing equations for porous media flow and allow ice infiltration of the pore space to occur at a critical effective stress N infiltration. For low values of N infiltration, ice infiltration of sediment allows these conduits to follow their original paths. Where insufficient ice infiltration occurs, the conduit path instead lies parallel to the direction of ice flow. Our results speak to the importance of incorporating small-scale processes into models of subglacial hydrologic networks. Close

• 7. [Article] A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change

  Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from ...

  Citation × Citation Citation Abstract Copy Title: A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change Author: Praskievicz, Sarah Year: 2014 Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from climate change. Climate-driven hydrological changes are potentially significant for the fluvial geomorphology of river systems. In unchanging climatic and tectonic conditions, a river's morphology will develop in equilibrium with inputs of water and sediment, but climate change represents a potential forcing on these variables that may push the system into disequilibrium and cause significant changes in river morphology. Geomorphic factors, such as channel geometry, planform, and sediment transport, are major determinants of the value of river systems, including their suitability for threatened and endangered species and for human uses of water. This dissertation research uses a hierarchical modeling approach to investigate potential impacts of anthropogenic climate change on river morphology in the interior Pacific Northwest. The research will address the following theoretical and methodological objectives: 1) Develop downscaled climate change scenarios, based on regional climate-model output, including changes in daily minimum and maximum temperature and precipitation. 2) Estimate how climate change scenarios affect river discharge and suspended-sediment load, using a basin-scale hydrologic model. 3) Examine potential impacts of climate-driven hydrologic changes on stream power and shear stress, bedload sediment transport, and river morphology, including channel geometry and planform. The downscaling approach, based on empirically-estimated local topographic lapse rates, produces high-resolution climate grids with positive forecast skill. The hydrologic modeling results indicate that projected climate change in the study rivers will change the annual cycle of hydrology, with increased winter discharge, a decrease in the magnitude of the spring snowmelt peak, and decreased summer discharge. Geomorphic modeling results suggest that changes in reach-averaged bedload transport are highly sensitive to likely changes in the recurrence interval of the critical discharge needed to mobilize bed sediments. This dissertation research makes an original contribution to the climate-change impacts literature by linking Earth processes across a wide range of spatial scales to project changes in river systems that may be significant for management of these systems for societal and ecological benefits. This dissertation includes unpublished co-authored material. Title: A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change Author: Praskievicz, Sarah Year: 2014 Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from climate change. Climate-driven hydrological changes are potentially significant for the fluvial geomorphology of river systems. In unchanging climatic and tectonic conditions, a river's morphology will develop in equilibrium with inputs of water and sediment, but climate change represents a potential forcing on these variables that may push the system into disequilibrium and cause significant changes in river morphology. Geomorphic factors, such as channel geometry, planform, and sediment transport, are major determinants of the value of river systems, including their suitability for threatened and endangered species and for human uses of water. This dissertation research uses a hierarchical modeling approach to investigate potential impacts of anthropogenic climate change on river morphology in the interior Pacific Northwest. The research will address the following theoretical and methodological objectives: 1) Develop downscaled climate change scenarios, based on regional climate-model output, including changes in daily minimum and maximum temperature and precipitation. 2) Estimate how climate change scenarios affect river discharge and suspended-sediment load, using a basin-scale hydrologic model. 3) Examine potential impacts of climate-driven hydrologic changes on stream power and shear stress, bedload sediment transport, and river morphology, including channel geometry and planform. The downscaling approach, based on empirically-estimated local topographic lapse rates, produces high-resolution climate grids with positive forecast skill. The hydrologic modeling results indicate that projected climate change in the study rivers will change the annual cycle of hydrology, with increased winter discharge, a decrease in the magnitude of the spring snowmelt peak, and decreased summer discharge. Geomorphic modeling results suggest that changes in reach-averaged bedload transport are highly sensitive to likely changes in the recurrence interval of the critical discharge needed to mobilize bed sediments. This dissertation research makes an original contribution to the climate-change impacts literature by linking Earth processes across a wide range of spatial scales to project changes in river systems that may be significant for management of these systems for societal and ecological benefits. This dissertation includes unpublished co-authored material. Close

• 8. [Article] Paying the water bill : community support for agriculture and river restoration in central Oregon

  2 pages

  Citation × Citation Citation Abstract Copy Title: Paying the water bill : community support for agriculture and river restoration in central Oregon Author: University of Oregon. Ecosystem Workforce Program Year: 2016, 2013 2 pages Title: Paying the water bill : community support for agriculture and river restoration in central Oregon Author: University of Oregon. Ecosystem Workforce Program Year: 2016, 2013 2 pages Close

• 9. [Article] After the Flow: Landscape Response to the Emplacement of Holocene Lava Flows, Central Oregon Cascades, USA

  Effusive volcanic eruptions repave landscapes rapidly with lava flows, resetting the underlying landscape and ecosystem. The unique physical properties of lava pose interesting challenges for recovery, ...

  Citation × Citation Citation Abstract Copy Title: After the Flow: Landscape Response to the Emplacement of Holocene Lava Flows, Central Oregon Cascades, USA Author: Deligne, Natalia Year: 2012 Effusive volcanic eruptions repave landscapes rapidly with lava flows, resetting the underlying landscape and ecosystem. The unique physical properties of lava pose interesting challenges for recovery, as lava flows can be highly permeable while lava itself is dense, sterile, and generally inhospitable towards life. This dissertation examines two aspects of landscape recovery following lava flow emplacement: (1) hydrologic adaptation of surface and groundwater to recent volcanism and (2) plant colonization of young lava flows. I examine two sites in the central Oregon Cascades: the c. 3 ka Sand Mountain volcanic field (SMVF), located in the headwaters of the McKenzie River, a critical water resource for the state of Oregon, and the c. 1.5 ka Collier Cone lava flow, originating on the north flanks of North Sister volcano. My investigation of the SMVF and upper McKenzie River watershed reveals a complex volcanic history with profound impacts on the configuration and short-term discharge of the McKenzie River: lava flows from the SMVF and other Holocene vents have buried, dammed, and altered the path of the McKenzie River. Moreover, given the large groundwater contribution from the SMVF to the McKenzie River, I estimate that SMVF activity caused McKenzie River discharge in present-day Eugene, Oregon to decrease by up to 20% for days to months at a time; future regional mafic volcanic activity could have a similar impact. The SMVF and the Collier Cone lava flow are notable for the juxtaposition of barren exposed lava and mature forests on the same or similarly aged lava flows. I use a combination of LiDAR analysis, field observations, and soil characterization to examine soil and vegetation at these two sites and find that the presence of an external soil source greatly facilitates plant establishment, growth, and survival. Here, external soil sources are syn- or post-eruptive tephra (SMVF) or flood-borne deposits (Collier Cone lava flow). External soil appears to provide a substrate for plants to grow in along with key nutrients and sufficient moisture; overall, external soil sources are key for the initial recovery following an effusive volcanic disturbance. This dissertation includes co-authored material submitted for publication. Title: After the Flow: Landscape Response to the Emplacement of Holocene Lava Flows, Central Oregon Cascades, USA Author: Deligne, Natalia Year: 2012 Effusive volcanic eruptions repave landscapes rapidly with lava flows, resetting the underlying landscape and ecosystem. The unique physical properties of lava pose interesting challenges for recovery, as lava flows can be highly permeable while lava itself is dense, sterile, and generally inhospitable towards life. This dissertation examines two aspects of landscape recovery following lava flow emplacement: (1) hydrologic adaptation of surface and groundwater to recent volcanism and (2) plant colonization of young lava flows. I examine two sites in the central Oregon Cascades: the c. 3 ka Sand Mountain volcanic field (SMVF), located in the headwaters of the McKenzie River, a critical water resource for the state of Oregon, and the c. 1.5 ka Collier Cone lava flow, originating on the north flanks of North Sister volcano. My investigation of the SMVF and upper McKenzie River watershed reveals a complex volcanic history with profound impacts on the configuration and short-term discharge of the McKenzie River: lava flows from the SMVF and other Holocene vents have buried, dammed, and altered the path of the McKenzie River. Moreover, given the large groundwater contribution from the SMVF to the McKenzie River, I estimate that SMVF activity caused McKenzie River discharge in present-day Eugene, Oregon to decrease by up to 20% for days to months at a time; future regional mafic volcanic activity could have a similar impact. The SMVF and the Collier Cone lava flow are notable for the juxtaposition of barren exposed lava and mature forests on the same or similarly aged lava flows. I use a combination of LiDAR analysis, field observations, and soil characterization to examine soil and vegetation at these two sites and find that the presence of an external soil source greatly facilitates plant establishment, growth, and survival. Here, external soil sources are syn- or post-eruptive tephra (SMVF) or flood-borne deposits (Collier Cone lava flow). External soil appears to provide a substrate for plants to grow in along with key nutrients and sufficient moisture; overall, external soil sources are key for the initial recovery following an effusive volcanic disturbance. This dissertation includes co-authored material submitted for publication. Close

• 10. [Article] EFFECTS OF ACUTE PASSIVE HEAT EXPOSURE

  42 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, ...

  Citation × Citation Citation Abstract Copy Title: EFFECTS OF ACUTE PASSIVE HEAT EXPOSURE Author: Harris, Sarianne Year: 2016 42 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Title: EFFECTS OF ACUTE PASSIVE HEAT EXPOSURE Author: Harris, Sarianne Year: 2016 42 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Close