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• 81. [Article] Inventory and Mapping of Aquatic Plants at Lake Roosevelt National Recreation Area

  Lake Roosevelt is a large reservoir in northeast Washington State formed by the Grand Coulee Dam. The reservoir, which inundates portions of the Columbia River, the Spokane River, and other rivers and ...

  Citation × Citation Citation Abstract Copy Title: Inventory and Mapping of Aquatic Plants at Lake Roosevelt National Recreation Area Author: Sytsma, Mark D., Miller, Rich Year: 2008 Lake Roosevelt is a large reservoir in northeast Washington State formed by the Grand Coulee Dam. The reservoir, which inundates portions of the Columbia River, the Spokane River, and other rivers and streams, is the focus of the Lake Roosevelt National Recreation Area (LARO) that is managed by the National Park Service. LARO encompasses 100,390 acres (40,625 ha) and includes significant cultural and recreational resources. The surface area, volume, and shoreline length of Lake Roosevelt at full pool is 82,691 acres (33,490 ha), 9.41 × 1010 acre-ft (1.16 × 1010 m3) (Nigro et. al. 1981), and 630 miles (1014 km) (www.lrf.org/AboutLR/ALRFastFacts.html accessed 28 January 2008), respectively; thus, the reservoir provides a significant aquatic resource for fish and wildlife as well as recreation in the region. Invasive plants are a high-priority “vital sign” of LARO ecosystem health (Garret et. al. 2007). In recent years, LARO staff noted an increase in the density of submersed aquatic plants (macrophytes), including Myriophyllum spicatum (Eurasian watermilfoil), in the lake. M. spicatum is a highly invasive weed that forms dense surface mats that interfere with boating and angling and degrade water quality. In an effort to reduce recreational impacts of aquatic plants LARO staff established test plots of nonchemical methods of control during the drawdown period in the spring of 2007. The National Park Service contracted Portland State University Center for Lakes and Reservoirs to accomplish two main objectives: 1) document the effects of nonchemical control measures of submersed aquatic plants in the reservoir, and 2) describe the composition of the aquatic plant community at selected locations in LARO. Title: Inventory and Mapping of Aquatic Plants at Lake Roosevelt National Recreation Area Author: Sytsma, Mark D., Miller, Rich Year: 2008 Lake Roosevelt is a large reservoir in northeast Washington State formed by the Grand Coulee Dam. The reservoir, which inundates portions of the Columbia River, the Spokane River, and other rivers and streams, is the focus of the Lake Roosevelt National Recreation Area (LARO) that is managed by the National Park Service. LARO encompasses 100,390 acres (40,625 ha) and includes significant cultural and recreational resources. The surface area, volume, and shoreline length of Lake Roosevelt at full pool is 82,691 acres (33,490 ha), 9.41 × 1010 acre-ft (1.16 × 1010 m3) (Nigro et. al. 1981), and 630 miles (1014 km) (www.lrf.org/AboutLR/ALRFastFacts.html accessed 28 January 2008), respectively; thus, the reservoir provides a significant aquatic resource for fish and wildlife as well as recreation in the region. Invasive plants are a high-priority “vital sign” of LARO ecosystem health (Garret et. al. 2007). In recent years, LARO staff noted an increase in the density of submersed aquatic plants (macrophytes), including Myriophyllum spicatum (Eurasian watermilfoil), in the lake. M. spicatum is a highly invasive weed that forms dense surface mats that interfere with boating and angling and degrade water quality. In an effort to reduce recreational impacts of aquatic plants LARO staff established test plots of nonchemical methods of control during the drawdown period in the spring of 2007. The National Park Service contracted Portland State University Center for Lakes and Reservoirs to accomplish two main objectives: 1) document the effects of nonchemical control measures of submersed aquatic plants in the reservoir, and 2) describe the composition of the aquatic plant community at selected locations in LARO. Close

• 82. [Article] Modeling Historic Columbia River Flood Impacts

  The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling ...

  Citation × Citation Citation Abstract Copy Title: Modeling Historic Columbia River Flood Impacts Author: Helaire, Lumas, Mahedy, Andrew, Talke, Stefan A., Jay, David A Year: 2014 The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19th century. In this research project we look at several river flow scenarios. We are interested in the interaction between river flow and ocean tides, how it has changed in the LCRE since the 19th century and how it affects the river physics. With the model, we focus on the following questions: How has the spatial structure of salinity changed since the 1890's? Has the salinity intrusion length increased or decreased? Is there a change in residual salinity in some of the bays in the estuary? How have changes to the bathymetric structure of the river affected salinity intrusion? For the same flow river flow, how have wetland inundation patterns changed? How have changes to the tidal prism ascertained from a temporal analysis of tidal records, affected the amount of land inundated in a tidal cycle and how long that land remains inundated? Initial results suggest that salinity intrusion patterns have shifted and that wetland inundation patterns have been impacted by the up to 10% increase in the estuary tidal range since the late 19th century. Title: Modeling Historic Columbia River Flood Impacts Author: Helaire, Lumas, Mahedy, Andrew, Talke, Stefan A., Jay, David A Year: 2014 The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19th century. In this research project we look at several river flow scenarios. We are interested in the interaction between river flow and ocean tides, how it has changed in the LCRE since the 19th century and how it affects the river physics. With the model, we focus on the following questions: How has the spatial structure of salinity changed since the 1890's? Has the salinity intrusion length increased or decreased? Is there a change in residual salinity in some of the bays in the estuary? How have changes to the bathymetric structure of the river affected salinity intrusion? For the same flow river flow, how have wetland inundation patterns changed? How have changes to the tidal prism ascertained from a temporal analysis of tidal records, affected the amount of land inundated in a tidal cycle and how long that land remains inundated? Initial results suggest that salinity intrusion patterns have shifted and that wetland inundation patterns have been impacted by the up to 10% increase in the estuary tidal range since the late 19th century. Close

• 83. [Article] Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: II. Water Level Models, Floodplain Wetland Inundation, and System Zones

  Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) ...

  Citation × Citation Citation Abstract Copy Title: Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: II. Water Level Models, Floodplain Wetland Inundation, and System Zones Author: Jay, David A, Borde, Amy B., Diefenderfer, Heida Year: 2016 Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland hydrologic regimes at different locations on the river floodplain. A new predictive tool is introduced and validated, the potential SEV (pSEV), which can reduce the need for extensive new data collection in wetland restoration planning. Models of water levels and inundation frequency distinguish four zones encompassing eight reaches. The system zones are the wave- and current-dominated Entrance to river kilometer (rkm) 5; the Estuary (rkm-5 to 87), comprised of a lower reach with salinity, the energy minimum (where the turbidity maximum normally occurs), and an upper estuary reach without salinity; the Tidal River (rkm-87 to 229), with lower, middle, and upper reaches in which river flow becomes increasingly dominant over tides in determining water levels; and the steep and weakly tidal Cascade (rkm-229 to 234) immediately downstream from Bonneville Dam. The same zonation is seen in the water levels of floodplain stations, with considerable modification of tidal properties. The system zones and reaches defined here reflect geological features and their boundaries are congruent with five wetland vegetation zones. Title: Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: II. Water Level Models, Floodplain Wetland Inundation, and System Zones Author: Jay, David A, Borde, Amy B., Diefenderfer, Heida Year: 2016 Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland hydrologic regimes at different locations on the river floodplain. A new predictive tool is introduced and validated, the potential SEV (pSEV), which can reduce the need for extensive new data collection in wetland restoration planning. Models of water levels and inundation frequency distinguish four zones encompassing eight reaches. The system zones are the wave- and current-dominated Entrance to river kilometer (rkm) 5; the Estuary (rkm-5 to 87), comprised of a lower reach with salinity, the energy minimum (where the turbidity maximum normally occurs), and an upper estuary reach without salinity; the Tidal River (rkm-87 to 229), with lower, middle, and upper reaches in which river flow becomes increasingly dominant over tides in determining water levels; and the steep and weakly tidal Cascade (rkm-229 to 234) immediately downstream from Bonneville Dam. The same zonation is seen in the water levels of floodplain stations, with considerable modification of tidal properties. The system zones and reaches defined here reflect geological features and their boundaries are congruent with five wetland vegetation zones. Close

• 84. [Article] Application of CE-QUAL-W2 on Tigris River in Iraq

  The Tigris River is the eastern member of the two great rivers in Iraq. Two big rivers pass through Iraq, Mesopotamia. Tigris and Euphrates Rivers with their tributaries form a major river system in the ...

  Citation × Citation Citation Abstract Copy Title: Application of CE-QUAL-W2 on Tigris River in Iraq Author: Al-Murib, Muhanned Year: 2014 The Tigris River is the eastern member of the two great rivers in Iraq. Two big rivers pass through Iraq, Mesopotamia. Tigris and Euphrates Rivers with their tributaries form a major river system in the Middle East. Four riparian countries, Turkey, Syria, Iran, and Iraq, share the Tigris River basin area and Iraq has the majority of this basin area. The total length of the Tigris is 1850 km from which 1418 km is within Iraq. A study area of 880 km from Mosul dam to Kut barrage is modeled using a water quality CE-QUAL-W2 model. CE-QUAL-W2 is a two-dimensional (longitudinal and vertical) water quality model developed by the U.S. Army Corps of Engineers and Portland State University. W2 simulates river circulation, stage, vertical and horizontal velocities, water temperature, and a host of water quality constituents. Total dissolved solids (TDS) is the main concern in Iraq because Iraq heavily depends on its water for irrigation purposes. Therefore, this project discusses the implementation of CE-QUAL-W2 model on Tigris River to simulate flow, temperature, and TDS. Title: Application of CE-QUAL-W2 on Tigris River in Iraq Author: Al-Murib, Muhanned Year: 2014 The Tigris River is the eastern member of the two great rivers in Iraq. Two big rivers pass through Iraq, Mesopotamia. Tigris and Euphrates Rivers with their tributaries form a major river system in the Middle East. Four riparian countries, Turkey, Syria, Iran, and Iraq, share the Tigris River basin area and Iraq has the majority of this basin area. The total length of the Tigris is 1850 km from which 1418 km is within Iraq. A study area of 880 km from Mosul dam to Kut barrage is modeled using a water quality CE-QUAL-W2 model. CE-QUAL-W2 is a two-dimensional (longitudinal and vertical) water quality model developed by the U.S. Army Corps of Engineers and Portland State University. W2 simulates river circulation, stage, vertical and horizontal velocities, water temperature, and a host of water quality constituents. Total dissolved solids (TDS) is the main concern in Iraq because Iraq heavily depends on its water for irrigation purposes. Therefore, this project discusses the implementation of CE-QUAL-W2 model on Tigris River to simulate flow, temperature, and TDS. Close

• 85. [Article] Fetal Stress and Neurogenesis in Thamnophis sirtalis parietalis

  Little is currently known about normal brain development and the growth of new nerve cells, known as neurogenesis, in most species, let alone how exposure to prenatal stress affects these processes. Using ...

  Citation × Citation Citation Abstract Copy Title: Fetal Stress and Neurogenesis in Thamnophis sirtalis parietalis Author: Stratton, Kalera Year: 2016 Little is currently known about normal brain development and the growth of new nerve cells, known as neurogenesis, in most species, let alone how exposure to prenatal stress affects these processes. Using red-sided garter snakes as our animal model, we have a unique opportunity to study the impact of exposure to elevated maternal glucocorticoids, commonly known as "stress hormones", on brain development. This species is viviparous, with a proto-placental structure through which developing fetuses receive nutrients from the dam. Adult snakes also exhibit high rates of seasonal changes in neurogenesis. We captured mated female snakes and treated one-third of them with subcutaneous glucocorticoid hormone implants, one-third with subcutaneous metyrapone, a glucocorticoid synthesis inhibitor, and one-third with a subcutaneous blank control capsule. At ~14 weeks following birth, we injected the neonates with BrdU, a thymidine analog that is incorporated into the DNA of newly-formed cells. We euthanized the neonates at ~15 weeks of age. Immunohistochemistry for BrdU was followed by manually counting the number of stained neurons and statistical analyses to determine differences in neurogenesis between groups. The metyrapone-treated group had significantly reduced brain cell proliferation compared to the control group (P=0.024). While the difference was not statistically significant (P=0.058), the corticosterone group also had reduced brain cell proliferation compared to the control group. These findings suggest that animals whose glucocorticoid levels are disrupted by environmental factors (i.e. heavy predation threat or compromised habitat) produce offspring with compromised brain development. Title: Fetal Stress and Neurogenesis in Thamnophis sirtalis parietalis Author: Stratton, Kalera Year: 2016 Little is currently known about normal brain development and the growth of new nerve cells, known as neurogenesis, in most species, let alone how exposure to prenatal stress affects these processes. Using red-sided garter snakes as our animal model, we have a unique opportunity to study the impact of exposure to elevated maternal glucocorticoids, commonly known as "stress hormones", on brain development. This species is viviparous, with a proto-placental structure through which developing fetuses receive nutrients from the dam. Adult snakes also exhibit high rates of seasonal changes in neurogenesis. We captured mated female snakes and treated one-third of them with subcutaneous glucocorticoid hormone implants, one-third with subcutaneous metyrapone, a glucocorticoid synthesis inhibitor, and one-third with a subcutaneous blank control capsule. At ~14 weeks following birth, we injected the neonates with BrdU, a thymidine analog that is incorporated into the DNA of newly-formed cells. We euthanized the neonates at ~15 weeks of age. Immunohistochemistry for BrdU was followed by manually counting the number of stained neurons and statistical analyses to determine differences in neurogenesis between groups. The metyrapone-treated group had significantly reduced brain cell proliferation compared to the control group (P=0.024). While the difference was not statistically significant (P=0.058), the corticosterone group also had reduced brain cell proliferation compared to the control group. These findings suggest that animals whose glucocorticoid levels are disrupted by environmental factors (i.e. heavy predation threat or compromised habitat) produce offspring with compromised brain development. Close

• 86. [Article] Wind and Hydropower Integration: A Socio-Political Evaluation of Bonneville Power Administration’s Management of Over-Generation and Spill

  The Columbia River is a dynamic water system, and for over a century the river’s resources have been used for a variety of purposes. Perhaps most notably are the series of dams located along most of the ...

  Citation × Citation Citation Abstract Copy Title: Wind and Hydropower Integration: A Socio-Political Evaluation of Bonneville Power Administration’s Management of Over-Generation and Spill Author: Fortney, David Year: 2012 The Columbia River is a dynamic water system, and for over a century the river’s resources have been used for a variety of purposes. Perhaps most notably are the series of dams located along most of the main stem of the river that provide multiple social, economic, and environmental benefits. One benefit of importance for the purposes of this paper is hydropower, which provides large amounts of electrical power to communities and industries across the Pacific Northwest (PNW) region. However, the success of hydropower’s long and productive history in the PNW has at times been clouded by socio-political, economic, and environmental issues that arise over how Columbia River water resources are managed for multiple uses and which ones take precedence. Further complicating these conflicts are ecological systems that can significantly alter the river’s conditions. Winter rain and spring snowmelt are two such characteristics of the river’s ecology that make the management of the river for hydropower purposes very difficult. Add another variable – the introduction and integration of wind power in this hydropower system and one quickly realizes that management of the river includes multiple actors with various agendas often resulting in conflict. The discussion below highlights the socio-political factors, as well as the regulatory and economic factors that, in their aggregate, exert pressure on the future of wind power deployment in the Bonneville Power Administration (BPA)’s balancing authority. I begin by describing a high water management problem that BPA and its stakeholders have encountered several times in the past few years, which is the key issue that I focus on that inhibits this deployment. I then delve into a discussion of the research methodology – SPEED, which is used to analyze the problem and provide a management roadmap forward. After the SPEED analysis, a brief discussion of the implications of this particular problem is provided. It should be noted before continuing that this discussion focuses on how to mitigate complex management challenges in supporting the continued deployment of technology innovations. Title: Wind and Hydropower Integration: A Socio-Political Evaluation of Bonneville Power Administration’s Management of Over-Generation and Spill Author: Fortney, David Year: 2012 The Columbia River is a dynamic water system, and for over a century the river’s resources have been used for a variety of purposes. Perhaps most notably are the series of dams located along most of the main stem of the river that provide multiple social, economic, and environmental benefits. One benefit of importance for the purposes of this paper is hydropower, which provides large amounts of electrical power to communities and industries across the Pacific Northwest (PNW) region. However, the success of hydropower’s long and productive history in the PNW has at times been clouded by socio-political, economic, and environmental issues that arise over how Columbia River water resources are managed for multiple uses and which ones take precedence. Further complicating these conflicts are ecological systems that can significantly alter the river’s conditions. Winter rain and spring snowmelt are two such characteristics of the river’s ecology that make the management of the river for hydropower purposes very difficult. Add another variable – the introduction and integration of wind power in this hydropower system and one quickly realizes that management of the river includes multiple actors with various agendas often resulting in conflict. The discussion below highlights the socio-political factors, as well as the regulatory and economic factors that, in their aggregate, exert pressure on the future of wind power deployment in the Bonneville Power Administration (BPA)’s balancing authority. I begin by describing a high water management problem that BPA and its stakeholders have encountered several times in the past few years, which is the key issue that I focus on that inhibits this deployment. I then delve into a discussion of the research methodology – SPEED, which is used to analyze the problem and provide a management roadmap forward. After the SPEED analysis, a brief discussion of the implications of this particular problem is provided. It should be noted before continuing that this discussion focuses on how to mitigate complex management challenges in supporting the continued deployment of technology innovations. Close

• 87. [Article] Beyond the Angle of Repose: A Review and Synthesis of Landslide Processes in Response to Rapid Uplift, Eel River, Northern Eel River, Northern California

  In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope ...

  Citation × Citation Citation Abstract Copy Title: Beyond the Angle of Repose: A Review and Synthesis of Landslide Processes in Response to Rapid Uplift, Eel River, Northern Eel River, Northern California Author: Roering, Joshua J., Mackey, Benjamin H., Handwerger, Alexander L., Booth, Adam M., Schmidt, David A., Bennett, Georgina L., Cerovski-Darriau, Corina Year: 2015 In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope angles approach a limiting value. For decades, the threshold slope model has been invoked to account for landslide-driven increases in sediment flux that limit topographic relief, but the manner by which slope failures organize themselves spatially and temporally in order for erosion to keep pace with rock uplift has not been well documented. Here, we review past work and present new findings from remote sensing, cosmogenic adionuclides, suspended sediment records, and airborne lidar data, to decipher patterns of landslide activity and geomorphic processes related to rapid uplift along the northward-migrating Mendocino Triple Junction in Northern California. From historical air photos and airborne lidar, we estimated the velocity and sediment flux associated with active, slow-moving landslides (or earthflows) in the mélange- and argillite-dominated Eel River watershed using the downslope displacement of surface markers such as trees and shrubs. Although active landslides that directly convey sediment into the channel network account for only 7% of the landscape surface, their sediment flux amounts to more than 50% of the suspended load recorded at downstream sediment gauging stations. These active slides tend to exhibit seasonal variations in velocity as satellite-based interferometry has demonstrated that rapid acceleration commences within 1 to 2 months of the onset of autumn rainfall events before slower deceleration ensues in the spring and summer months. Curiously, this seasonal velocity pattern does not appear to vary with landslide size, suggesting that complex hydrologic-mechanical feedbacks (rather than 1-D pore pressure diffusion) may govern slide dynamics. A new analysis of 14 years of discharge and sediment concentration data for the Eel River indicates that the characteristic mid-winter timing of earthflow acceleration corresponds with increased suspended concentration values, suggesting that the seasonal onset of landslide motion each year may be reflected in the export of sediments to the continental margin. The vast majority of active slides exhibit gullied surfaces and the gully networks, which are also seasonally active, may facilitate sediment export although the proportion of material produced by this pathway is poorly known. Along Kekawaka Creek, a prominent tributary to the Eel River, new analyses of catchment-averaged erosion rates derived from cosmogenic radionuclides reveal rapid erosion (0.76 mm/yr) below a prominent knickpoint and slower erosion (0.29 mm/yr) upstream. Such knickpoints are frequently observed in Eel tributaries and are usually comprised of massive (>10m) interlocking resistant boulders that likely persist in the landscape for long time periods (>105yr). Upstream of these knickpoints, active landslides tend to be less frequent and average slope angles are slightly gentler than in downstream areas, which indicates that landslide density and average slope angle appear to increase with erosion rate. Lastly, we synthesize evidence for the role of large, catastrophic landslides in regulating sediment flux and landscape form. The emergence of resistant blocks within the mélange bedrock has promoted large catastrophic slides that have dammed the Eel River and perhaps generated outburst events in the past. The frequency and impact of these landslide dams likely depend on the spatial and size distributions of resistant blocks relative to the width and drainage area of adjacent valley networks. Overall, our findings demonstrate that landslides within the Eel River catchment do not occur randomly, but instead exhibit spatial and temporal patterns related to baselevel lowering, climate forcing, and lithologic variations. Combined with recent landscape evolution models that incorporate landslides, these results provide predictive capability for estimating erosion rates and managing hazards in mountainous regions. Title: Beyond the Angle of Repose: A Review and Synthesis of Landslide Processes in Response to Rapid Uplift, Eel River, Northern Eel River, Northern California Author: Roering, Joshua J., Mackey, Benjamin H., Handwerger, Alexander L., Booth, Adam M., Schmidt, David A., Bennett, Georgina L., Cerovski-Darriau, Corina Year: 2015 In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope angles approach a limiting value. For decades, the threshold slope model has been invoked to account for landslide-driven increases in sediment flux that limit topographic relief, but the manner by which slope failures organize themselves spatially and temporally in order for erosion to keep pace with rock uplift has not been well documented. Here, we review past work and present new findings from remote sensing, cosmogenic adionuclides, suspended sediment records, and airborne lidar data, to decipher patterns of landslide activity and geomorphic processes related to rapid uplift along the northward-migrating Mendocino Triple Junction in Northern California. From historical air photos and airborne lidar, we estimated the velocity and sediment flux associated with active, slow-moving landslides (or earthflows) in the mélange- and argillite-dominated Eel River watershed using the downslope displacement of surface markers such as trees and shrubs. Although active landslides that directly convey sediment into the channel network account for only 7% of the landscape surface, their sediment flux amounts to more than 50% of the suspended load recorded at downstream sediment gauging stations. These active slides tend to exhibit seasonal variations in velocity as satellite-based interferometry has demonstrated that rapid acceleration commences within 1 to 2 months of the onset of autumn rainfall events before slower deceleration ensues in the spring and summer months. Curiously, this seasonal velocity pattern does not appear to vary with landslide size, suggesting that complex hydrologic-mechanical feedbacks (rather than 1-D pore pressure diffusion) may govern slide dynamics. A new analysis of 14 years of discharge and sediment concentration data for the Eel River indicates that the characteristic mid-winter timing of earthflow acceleration corresponds with increased suspended concentration values, suggesting that the seasonal onset of landslide motion each year may be reflected in the export of sediments to the continental margin. The vast majority of active slides exhibit gullied surfaces and the gully networks, which are also seasonally active, may facilitate sediment export although the proportion of material produced by this pathway is poorly known. Along Kekawaka Creek, a prominent tributary to the Eel River, new analyses of catchment-averaged erosion rates derived from cosmogenic radionuclides reveal rapid erosion (0.76 mm/yr) below a prominent knickpoint and slower erosion (0.29 mm/yr) upstream. Such knickpoints are frequently observed in Eel tributaries and are usually comprised of massive (>10m) interlocking resistant boulders that likely persist in the landscape for long time periods (>105yr). Upstream of these knickpoints, active landslides tend to be less frequent and average slope angles are slightly gentler than in downstream areas, which indicates that landslide density and average slope angle appear to increase with erosion rate. Lastly, we synthesize evidence for the role of large, catastrophic landslides in regulating sediment flux and landscape form. The emergence of resistant blocks within the mélange bedrock has promoted large catastrophic slides that have dammed the Eel River and perhaps generated outburst events in the past. The frequency and impact of these landslide dams likely depend on the spatial and size distributions of resistant blocks relative to the width and drainage area of adjacent valley networks. Overall, our findings demonstrate that landslides within the Eel River catchment do not occur randomly, but instead exhibit spatial and temporal patterns related to baselevel lowering, climate forcing, and lithologic variations. Combined with recent landscape evolution models that incorporate landslides, these results provide predictive capability for estimating erosion rates and managing hazards in mountainous regions. Close

• 88. [Article] Late Pleistocene and recent archaeology and geomorphology of the south shore of Harney Lake, Oregon

  The present study was a response to the discovery of two artifacts found in a ditch wall near Harney Lake, Oregon. These were lying on a buried lake floor that appeared to be of late Pleistocene or early ...

  Citation × Citation Citation Abstract Copy Title: Late Pleistocene and recent archaeology and geomorphology of the south shore of Harney Lake, Oregon Author: Gehr, Keith Donald Year: 1980 The present study was a response to the discovery of two artifacts found in a ditch wall near Harney Lake, Oregon. These were lying on a buried lake floor that appeared to be of late Pleistocene or early Recent age. Other sediments exposed in the ditch seemed to relate to at least some of the phases of the pluvial lake sequence in the Harney Basin. Three problems were considered: (1) the geomorphology and dating of the pluvial lake stillstands, (2) whether the original artifacts were part of a larger early site, and (3) whether there was any relationship between archaeological sites and geomorphic features in the area. These problems were approached in the field by stratigraphic mapping of exposed sediments and by an archaeological survey of a defined study area. Test excavations were made adjacent to the location of the original artifact discovery to search for other cultural material. Beachline records of four stillstands of Pluvial Lake Malheur are preserved in the exposed sediments. The youngest beachline is undated. Three others were 14C dated from associated fossil molluscs at 32,000, 9620 and 8680 B.P. At least in the case of the 8680 B.P. lake, the Harney Basin was filled to overflowing and was a part of the Columbia River system. The Voltage basalt flow, which dammed the outlet of the Basin in Malheur Gap, was in place by 32,000 years ago. There is no evidence for a diversion of the Basin outlet to Crane Gap following this event. Molluscan fossils and diatoms were used, along with soil texture analyses, to help identify and differentiate sedimentary deposits and to draw environmental inferences. Artifacts were found both on and beneath buried beach deposits of the 8680 B.P. lake. Four of the five sites in the study area were either on wave-cut terraces or other lakeshore features associated with this lake. Diagnostic artifacts are Lind Coulee points, crescents, basally ground leaf-shaped points, and what are apparently true blades. The sites seem to have been located to take advantage of shallow water littoral zone resources. Fish may have been an important dietary item of the early Harney Basin dwellers. Large salmonid vertebrae from fish in the 10 kg weight class are found on the playa. By using the relationship between landforms and elevations it may be possible to predict the general age class of other sites on the margin of the playas. Title: Late Pleistocene and recent archaeology and geomorphology of the south shore of Harney Lake, Oregon Author: Gehr, Keith Donald Year: 1980 The present study was a response to the discovery of two artifacts found in a ditch wall near Harney Lake, Oregon. These were lying on a buried lake floor that appeared to be of late Pleistocene or early Recent age. Other sediments exposed in the ditch seemed to relate to at least some of the phases of the pluvial lake sequence in the Harney Basin. Three problems were considered: (1) the geomorphology and dating of the pluvial lake stillstands, (2) whether the original artifacts were part of a larger early site, and (3) whether there was any relationship between archaeological sites and geomorphic features in the area. These problems were approached in the field by stratigraphic mapping of exposed sediments and by an archaeological survey of a defined study area. Test excavations were made adjacent to the location of the original artifact discovery to search for other cultural material. Beachline records of four stillstands of Pluvial Lake Malheur are preserved in the exposed sediments. The youngest beachline is undated. Three others were 14C dated from associated fossil molluscs at 32,000, 9620 and 8680 B.P. At least in the case of the 8680 B.P. lake, the Harney Basin was filled to overflowing and was a part of the Columbia River system. The Voltage basalt flow, which dammed the outlet of the Basin in Malheur Gap, was in place by 32,000 years ago. There is no evidence for a diversion of the Basin outlet to Crane Gap following this event. Molluscan fossils and diatoms were used, along with soil texture analyses, to help identify and differentiate sedimentary deposits and to draw environmental inferences. Artifacts were found both on and beneath buried beach deposits of the 8680 B.P. lake. Four of the five sites in the study area were either on wave-cut terraces or other lakeshore features associated with this lake. Diagnostic artifacts are Lind Coulee points, crescents, basally ground leaf-shaped points, and what are apparently true blades. The sites seem to have been located to take advantage of shallow water littoral zone resources. Fish may have been an important dietary item of the early Harney Basin dwellers. Large salmonid vertebrae from fish in the 10 kg weight class are found on the playa. By using the relationship between landforms and elevations it may be possible to predict the general age class of other sites on the margin of the playas. Close

• 89. [Article] A descriptive study of Thai nonverbal communication

  Nonverbal communication is especially significant in the area of intercultural communication. Familiar signals often signify and convey different and unexpected messages, usually out-of-awareness, and ...

  Citation × Citation Citation Abstract Copy Title: A descriptive study of Thai nonverbal communication Author: Smutkupt, Suriya Year: 1976 Nonverbal communication is especially significant in the area of intercultural communication. Familiar signals often signify and convey different and unexpected messages, usually out-of-awareness, and then unfamiliar stimuli cause confusion and uneasiness. This is a report of Thai NVC, which intends (1) to describe selected Thai nonverbal behavior, (2) to relate these to appropriate time and context, (3) to explain a cultural component that makes the behaviors acceptable and/or mandatory, and (4) to report how Thai nonverbal behaviors may affect intercultural and cross-cultural communication. Selected Thai nonverbal messages are described: (1) nonverbal signals: the sign language of wai, the kinesthetic behaviors of eye movement, and hand movements which include receiving, pointing, indicating farewell, rejection, negation, disagreement, beckoning, applause, counting, bad odor signal, insulting signal, and angry and friendly signals, (2) nonverbal action: the action of feet and khwan, postures which include sitting, walking and standing, (3) object language: four religious ceremonies of lod khrc kaaw pun, dam hua, wai khruu, and wi sa kha bu chaa; the use of artifacts: phra cee dii, phra phud tharubb, khryan raan ta krud, (dta gkroot) and jan, colors (clothing) which includes yellow, khaki, blue, red, daily color, black and white, the material orientation to directions such as staircase positions; cooking art which includes breakfast and eating, (4) paralanguage: the Thai linguistic parallel to paralanguage, especially vocal intensity (loudness and softness), (5) personal and social distance which includes proxemic behaviors of infancy, late childhood, adolescence, and adulthood, and male and female public positions, and male and female sleeping positions (6) olfaction: artificial scents and natural body odors, and finally (7) skin sensitivity: touch and temperature. The method used to gather data was through participant observation. The descriptions of these illustrative Thai NVC behaviors are drawn from the writer's personal firsthand knowledge of Thai life, from Thai informants, his field work experiences as a research assistant to a Cornell University anthropologist in Thailand, from his experience as an interpreter-translator for the U.S. Army there, and his observations of Thai nonverbal behaviors among Thai migrants and student s in many natural settings in ·the United States of America. The approach of “Participant Observation” is a social and cultural anthropological technique best described by Bruyn. The study shows that Thais are rigidly taught behaviors early in life, which portray nonverbal messages. These become a part of Thai cultural communication norms. Thus, Thais communicate through explicit and unquestioned sets of norms, using proper, desirable, and appropriate behavior for them. Since these cultural norms are taught early in life, they are out-of-awareness and deeply ingrained. Evidence is given that Thai NVC behavior is culturally interpreted. In intercultural and cross-cultural communication, this should be taken into consideration to prevent erroneous interpretation. Title: A descriptive study of Thai nonverbal communication Author: Smutkupt, Suriya Year: 1976 Nonverbal communication is especially significant in the area of intercultural communication. Familiar signals often signify and convey different and unexpected messages, usually out-of-awareness, and then unfamiliar stimuli cause confusion and uneasiness. This is a report of Thai NVC, which intends (1) to describe selected Thai nonverbal behavior, (2) to relate these to appropriate time and context, (3) to explain a cultural component that makes the behaviors acceptable and/or mandatory, and (4) to report how Thai nonverbal behaviors may affect intercultural and cross-cultural communication. Selected Thai nonverbal messages are described: (1) nonverbal signals: the sign language of wai, the kinesthetic behaviors of eye movement, and hand movements which include receiving, pointing, indicating farewell, rejection, negation, disagreement, beckoning, applause, counting, bad odor signal, insulting signal, and angry and friendly signals, (2) nonverbal action: the action of feet and khwan, postures which include sitting, walking and standing, (3) object language: four religious ceremonies of lod khrc kaaw pun, dam hua, wai khruu, and wi sa kha bu chaa; the use of artifacts: phra cee dii, phra phud tharubb, khryan raan ta krud, (dta gkroot) and jan, colors (clothing) which includes yellow, khaki, blue, red, daily color, black and white, the material orientation to directions such as staircase positions; cooking art which includes breakfast and eating, (4) paralanguage: the Thai linguistic parallel to paralanguage, especially vocal intensity (loudness and softness), (5) personal and social distance which includes proxemic behaviors of infancy, late childhood, adolescence, and adulthood, and male and female public positions, and male and female sleeping positions (6) olfaction: artificial scents and natural body odors, and finally (7) skin sensitivity: touch and temperature. The method used to gather data was through participant observation. The descriptions of these illustrative Thai NVC behaviors are drawn from the writer's personal firsthand knowledge of Thai life, from Thai informants, his field work experiences as a research assistant to a Cornell University anthropologist in Thailand, from his experience as an interpreter-translator for the U.S. Army there, and his observations of Thai nonverbal behaviors among Thai migrants and student s in many natural settings in ·the United States of America. The approach of “Participant Observation” is a social and cultural anthropological technique best described by Bruyn. The study shows that Thais are rigidly taught behaviors early in life, which portray nonverbal messages. These become a part of Thai cultural communication norms. Thus, Thais communicate through explicit and unquestioned sets of norms, using proper, desirable, and appropriate behavior for them. Since these cultural norms are taught early in life, they are out-of-awareness and deeply ingrained. Evidence is given that Thai NVC behavior is culturally interpreted. In intercultural and cross-cultural communication, this should be taken into consideration to prevent erroneous interpretation. Close

• 90. [Article] Contested Visions of Place: People, Power, and Perception on the Columbia's North Shore, 1805-1913

  This is a narrative of place, of intersections between people, power, and perception of landscape. The environs of the Columbia River Gorge create a very distinct sense of place. Where once a series of ...

  Citation × Citation Citation Abstract Copy Title: Contested Visions of Place: People, Power, and Perception on the Columbia's North Shore, 1805-1913 Author: Sinclair, Donna Lynn Year: 2004 This is a narrative of place, of intersections between people, power, and perception of landscape. The environs of the Columbia River Gorge create a very distinct sense of place. Where once a series of three rapids - the Cascades of the Columbia - blocked industrial upriver transport, now Bonneville Dam and Locks allows smooth passage. To the north the vast 1.3 million acre Gifford Pinchot National Forest dominates the landscape. On the Columbia's banks lies the town of Stevenson, Washington, with Carson a few miles away, in a transitory ecological zone between east and west, at the forest's edge. There, community development has been manifestly influenced by human relationships to the landscape. Contested visions of place during the nineteenth century resulted in violent conflict and framed debates over place.Examining struggles over who would control access, first to the Cascades of the Columbia, and then to the timber of the Wind River Valley, provides a venue for examining power - of nature, ideas, and changing human cultures as overlapping groups imposed their views of the good life onto the landscape. As each successive group gained power, the relationships of humans to the land, and to one another, changed. By examining historic connections between river and forest, and between human communities to each, this study identifies multiple meanings of the same environment for different groups. I use a bioregional approach, exploring relationships between land, people and resources on the Columbia's north bank between 1805 and 1913. Power relations at the Cascades and in the forest were determined through conflict, negotiation, and the federal government, with the human relationship to nature influencing outcomes. Conflict often resulted from struggles over access to place, while human groups negotiated their place within the landscape. Nature privileged one group over another through disease, fire, and human perception, while the United States government co-opted place through public land laws, Indian removal, and by measuring and bounding the landscape. Who gained access to the river and forest of the Columbia's north shore, and how they did it, is the focus of this story. Title: Contested Visions of Place: People, Power, and Perception on the Columbia's North Shore, 1805-1913 Author: Sinclair, Donna Lynn Year: 2004 This is a narrative of place, of intersections between people, power, and perception of landscape. The environs of the Columbia River Gorge create a very distinct sense of place. Where once a series of three rapids - the Cascades of the Columbia - blocked industrial upriver transport, now Bonneville Dam and Locks allows smooth passage. To the north the vast 1.3 million acre Gifford Pinchot National Forest dominates the landscape. On the Columbia's banks lies the town of Stevenson, Washington, with Carson a few miles away, in a transitory ecological zone between east and west, at the forest's edge. There, community development has been manifestly influenced by human relationships to the landscape. Contested visions of place during the nineteenth century resulted in violent conflict and framed debates over place.Examining struggles over who would control access, first to the Cascades of the Columbia, and then to the timber of the Wind River Valley, provides a venue for examining power - of nature, ideas, and changing human cultures as overlapping groups imposed their views of the good life onto the landscape. As each successive group gained power, the relationships of humans to the land, and to one another, changed. By examining historic connections between river and forest, and between human communities to each, this study identifies multiple meanings of the same environment for different groups. I use a bioregional approach, exploring relationships between land, people and resources on the Columbia's north bank between 1805 and 1913. Power relations at the Cascades and in the forest were determined through conflict, negotiation, and the federal government, with the human relationship to nature influencing outcomes. Conflict often resulted from struggles over access to place, while human groups negotiated their place within the landscape. Nature privileged one group over another through disease, fire, and human perception, while the United States government co-opted place through public land laws, Indian removal, and by measuring and bounding the landscape. Who gained access to the river and forest of the Columbia's north shore, and how they did it, is the focus of this story. Close