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• 311. [Article] Asthenosphere–lithosphere interactions in Western Saudi Arabia: Inferences from ³He/⁴He in xenoliths and lava flows from Harrat Hutaymah

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Asthenosphere–lithosphere interactions in Western Saudi Arabia: Inferences from ³He/⁴He in xenoliths and lava flows from Harrat Hutaymah Author: Kent, Adam J.R., Konrad, Kevin, Duncan, Robert A., Thornber, Carl R., Graham, David W., Al-Amri, Abdullah M. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/lithos/ Title: Asthenosphere–lithosphere interactions in Western Saudi Arabia: Inferences from ³He/⁴He in xenoliths and lava flows from Harrat Hutaymah Author: Kent, Adam J.R., Konrad, Kevin, Duncan, Robert A., Thornber, Carl R., Graham, David W., Al-Amri, Abdullah M. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/lithos/ Close

• 312. [Article] Entrainment, transport, and deposition of large woody debris in streams : results from a series of flume experiments

  Although there has been extensive research on the geomorphic and ecologic role of large woody debris (LWD) in streams, the dynamics of LWD in streams are poorly known due to various measurement difficulties ...

  Citation × Citation Citation Abstract Copy Title: Entrainment, transport, and deposition of large woody debris in streams : results from a series of flume experiments Author: Braudrick, Christian A. Although there has been extensive research on the geomorphic and ecologic role of large woody debris (LWD) in streams, the dynamics of LWD in streams are poorly known due to various measurement difficulties during floods. In this thesis I present the results of two flume experiments on the dynamics of wood in streams. The first experiment examined the effects of piece interaction on wood transport, while the second evaluated a theoretical model predicting the threshold of movement, and factors controlling the deposition of individual logs. Flume experiments allow us to model the wood movement under a variety of piece geometries, piece concentrations, and hydraulic conditions. The first experiment showed that logs moved in three distinct transport regimes; congested, semi-congested, and uncongested transport. During congested transport the logs move as a single mass and occupy > 33 % of the channel area. Uncongested transport occurs when the logs are moving as individuals and occupy < 10 % of the channel area. Semi-congested transport is intermediate between these two transport regimes and occurs when wood moves in clumps of 2-3 logs. Transport regime was dependent upon the ration of the volumetric input rate of pieces to the flow, and to a lesser degree, the ratios of the piece length to channel width and piece diameter to channel depth. The transport regime was reflected in the deposit. Congested transport deposits have a higher portion of their pieces oriented parallel to flow than uncongested and semi-congested transport. We expect that congested transport will occur in low-order channels where input rates are high and channel geometry is small relative to piece size. Uncongested transport will dominate large channels where input rates are lower relative to flow and channel geometry is large relative to piece size. Our theoretical model and these experiments indicate that the entrainment of individual logs was dependent upon the angle of the piece, and the presence/absence of rootwads. Although previously noted as a first-order control on piece movement, piece length had little effect on the entrainment threshold, but did affect the distance transported. The distance transported decreased with increases in the ratios of the piece length to average channel width (L[subscript log]/w[subscript av]), the piece length to the radius of curvature (L[subscript log]/R[subscript c]), and the piece diameter relative to average depth (D[subscript log]/D[subscript av]). These three ratios comprise the debris roughness. Increased debris roughness caused a general decrease in distance transported. Pieces with high debris roughness can travel further than predicted if they have high momentum, and over 50 % of their channel area deeper than the depth at which the piece floats. These results indicate that flume experiments and theoretical models, tools that have been extensively used to study sediment dynamics, are a useful in examining wood dynamics. Title: Entrainment, transport, and deposition of large woody debris in streams : results from a series of flume experiments Author: Braudrick, Christian A. Although there has been extensive research on the geomorphic and ecologic role of large woody debris (LWD) in streams, the dynamics of LWD in streams are poorly known due to various measurement difficulties during floods. In this thesis I present the results of two flume experiments on the dynamics of wood in streams. The first experiment examined the effects of piece interaction on wood transport, while the second evaluated a theoretical model predicting the threshold of movement, and factors controlling the deposition of individual logs. Flume experiments allow us to model the wood movement under a variety of piece geometries, piece concentrations, and hydraulic conditions. The first experiment showed that logs moved in three distinct transport regimes; congested, semi-congested, and uncongested transport. During congested transport the logs move as a single mass and occupy > 33 % of the channel area. Uncongested transport occurs when the logs are moving as individuals and occupy < 10 % of the channel area. Semi-congested transport is intermediate between these two transport regimes and occurs when wood moves in clumps of 2-3 logs. Transport regime was dependent upon the ration of the volumetric input rate of pieces to the flow, and to a lesser degree, the ratios of the piece length to channel width and piece diameter to channel depth. The transport regime was reflected in the deposit. Congested transport deposits have a higher portion of their pieces oriented parallel to flow than uncongested and semi-congested transport. We expect that congested transport will occur in low-order channels where input rates are high and channel geometry is small relative to piece size. Uncongested transport will dominate large channels where input rates are lower relative to flow and channel geometry is large relative to piece size. Our theoretical model and these experiments indicate that the entrainment of individual logs was dependent upon the angle of the piece, and the presence/absence of rootwads. Although previously noted as a first-order control on piece movement, piece length had little effect on the entrainment threshold, but did affect the distance transported. The distance transported decreased with increases in the ratios of the piece length to average channel width (L[subscript log]/w[subscript av]), the piece length to the radius of curvature (L[subscript log]/R[subscript c]), and the piece diameter relative to average depth (D[subscript log]/D[subscript av]). These three ratios comprise the debris roughness. Increased debris roughness caused a general decrease in distance transported. Pieces with high debris roughness can travel further than predicted if they have high momentum, and over 50 % of their channel area deeper than the depth at which the piece floats. These results indicate that flume experiments and theoretical models, tools that have been extensively used to study sediment dynamics, are a useful in examining wood dynamics. Close

• 313. [Article] Population genetics, ecology and evolution of a vertebrate metacommunity

  Population genetic structure is widespread in many organisms and can be found at small spatial scales. Fine-scale differentiation is the result of ecological and evolutionary processes working together ...

  Citation × Citation Citation Abstract Copy Title: Population genetics, ecology and evolution of a vertebrate metacommunity Author: Manier, Mollie Kim Population genetic structure is widespread in many organisms and can be found at small spatial scales. Fine-scale differentiation is the result of ecological and evolutionary processes working together to produce an overall pattern, but the relative importance of these factors in population differentiation is poorly understood. The goals of my research were to describe patterns of population genetic differentiation and to identify ecological and evolutionary factors important for population divergence. To this end, I investigated several aspects of genetic differentiation for three vertebrates in northern California. The focal species were the terrestrial garter snake (Thamnophis elegans) and the common garter snake (Thamnophis sirtalis) that occupy a series of ponds, lakes and flooded meadows in northern California. I found significant genetic differentiation and isolation by distance, as well as correlated patterns of pairwise divergence in both species. Independent estimates of effective population size and bi-directional migration rates also uncovered source-sink dynamics in both species that suggest frequent extinction-recolonization events within a metapopulation context. The generality of source-sink dynamics for an ecologically similar species within the same ecosystem was explored using a third species, B. boreas. I also identified ecological correlates of several population genetic parameters for all three species. Although F[subscript ST] were similar, B. boreas had larger effective population sizes, lower migration rates, lacked source-sink dynamics, and appeared to be in migration-drift equilibrium, indicative of a temporally stable population structure. A clustering analysis identified a series of block faults as a common barrier to dispersal for both garter snakes, and ecological correlates were found to be more similar among response variables than within species. I then compared degree of genetic differentiation at quantitative traits with that at neutral markers to infer strength of selection and adaptive divergence between two ecotypes of T. elegans. Selection on most traits was relatively weak, but strong diversifying selection was found for background coloration, total number of ventral scales and number of infralabials. Overall, my research documented ecological and evolutionary processes associated with population differentiation in a metacommunity and respresents an important contribution toward the unification of ecology and evolutionary biology. Title: Population genetics, ecology and evolution of a vertebrate metacommunity Author: Manier, Mollie Kim Population genetic structure is widespread in many organisms and can be found at small spatial scales. Fine-scale differentiation is the result of ecological and evolutionary processes working together to produce an overall pattern, but the relative importance of these factors in population differentiation is poorly understood. The goals of my research were to describe patterns of population genetic differentiation and to identify ecological and evolutionary factors important for population divergence. To this end, I investigated several aspects of genetic differentiation for three vertebrates in northern California. The focal species were the terrestrial garter snake (Thamnophis elegans) and the common garter snake (Thamnophis sirtalis) that occupy a series of ponds, lakes and flooded meadows in northern California. I found significant genetic differentiation and isolation by distance, as well as correlated patterns of pairwise divergence in both species. Independent estimates of effective population size and bi-directional migration rates also uncovered source-sink dynamics in both species that suggest frequent extinction-recolonization events within a metapopulation context. The generality of source-sink dynamics for an ecologically similar species within the same ecosystem was explored using a third species, B. boreas. I also identified ecological correlates of several population genetic parameters for all three species. Although F[subscript ST] were similar, B. boreas had larger effective population sizes, lower migration rates, lacked source-sink dynamics, and appeared to be in migration-drift equilibrium, indicative of a temporally stable population structure. A clustering analysis identified a series of block faults as a common barrier to dispersal for both garter snakes, and ecological correlates were found to be more similar among response variables than within species. I then compared degree of genetic differentiation at quantitative traits with that at neutral markers to infer strength of selection and adaptive divergence between two ecotypes of T. elegans. Selection on most traits was relatively weak, but strong diversifying selection was found for background coloration, total number of ventral scales and number of infralabials. Overall, my research documented ecological and evolutionary processes associated with population differentiation in a metacommunity and respresents an important contribution toward the unification of ecology and evolutionary biology. Close

• 314. [Article] Beaver ecology on the west Copper River Delta, Alaska

  Since the 1964 earthquake and geologic uplift, beavers (Castor canadensis) have expanded their historic range from the inland (outwash plain) Copper River Delta, Alaska to the once tidally influenced ...

  Citation × Citation Citation Abstract Copy Title: Beaver ecology on the west Copper River Delta, Alaska Author: Cooper, Erin E. Since the 1964 earthquake and geologic uplift, beavers (Castor canadensis) have expanded their historic range from the inland (outwash plain) Copper River Delta, Alaska to the once tidally influenced areas of the outer area (uplifted marsh). The uplift presents a unique opportunity to observe beaver expansion, habitat selection and influence on hydrologic structure of a coastal wetland ecosystem after a major disturbance. First, I examined the relationship between the sites of active beaver lodges and associated water and vegetative features (Chapter 2). I hypothesized that active lodge sites would be associated with distinct water features and woody vegetation types in each landscape. I used aerial photographic and ground survey methods to compare sightability and to determine habitat associations. I developed an a priori set of models to determine active beaver lodge occurrence using logistic regression with presence and absence as the response variables and water features and vegetation cover as the dependent variables. My results were similar between survey methods but differed between the two major landscape types. In the uplifted marsh, odds of an active lodge occurrance increased with the presence of former tidal sloughs and an increase in mixed shrub coverage. The odds of an active lodge occurrence increased with the presence of streams and decreased with increasing closed cottonwood-alder-willow coverage in the outwash plain. Post earthquake uplift, beaver now exploit a unique topographic setting through the use and modification of former tidal sloughs and a transitioning mixed shrub vegetation community. Second, I quantified the influence of beaver on the surface water of the West Copper River Delta using remote sensing (Chapter 3). Water features were documented from digitized aerial photographs from 1959, 1974, 1986, 1992/1993, and 1996. My results showed that surface water area in beaver influenced water impoundments increased from 0 to 20% from 1959 to 1996, concurrent with beaver colonization of the uplifted marsh. These results suggest that beavers may have altered the trajectory of wetland change on the West Copper River Delta by raising the water table within open water basins and flooding those areas that would have otherwise drained. Beaver may be used an effective management tool in wetland restoration where key habitat features are available. Title: Beaver ecology on the west Copper River Delta, Alaska Author: Cooper, Erin E. Since the 1964 earthquake and geologic uplift, beavers (Castor canadensis) have expanded their historic range from the inland (outwash plain) Copper River Delta, Alaska to the once tidally influenced areas of the outer area (uplifted marsh). The uplift presents a unique opportunity to observe beaver expansion, habitat selection and influence on hydrologic structure of a coastal wetland ecosystem after a major disturbance. First, I examined the relationship between the sites of active beaver lodges and associated water and vegetative features (Chapter 2). I hypothesized that active lodge sites would be associated with distinct water features and woody vegetation types in each landscape. I used aerial photographic and ground survey methods to compare sightability and to determine habitat associations. I developed an a priori set of models to determine active beaver lodge occurrence using logistic regression with presence and absence as the response variables and water features and vegetation cover as the dependent variables. My results were similar between survey methods but differed between the two major landscape types. In the uplifted marsh, odds of an active lodge occurrance increased with the presence of former tidal sloughs and an increase in mixed shrub coverage. The odds of an active lodge occurrence increased with the presence of streams and decreased with increasing closed cottonwood-alder-willow coverage in the outwash plain. Post earthquake uplift, beaver now exploit a unique topographic setting through the use and modification of former tidal sloughs and a transitioning mixed shrub vegetation community. Second, I quantified the influence of beaver on the surface water of the West Copper River Delta using remote sensing (Chapter 3). Water features were documented from digitized aerial photographs from 1959, 1974, 1986, 1992/1993, and 1996. My results showed that surface water area in beaver influenced water impoundments increased from 0 to 20% from 1959 to 1996, concurrent with beaver colonization of the uplifted marsh. These results suggest that beavers may have altered the trajectory of wetland change on the West Copper River Delta by raising the water table within open water basins and flooding those areas that would have otherwise drained. Beaver may be used an effective management tool in wetland restoration where key habitat features are available. Close

• 315. [Article] Stratigraphy, sedimentology, and petrology of neogene rocks in the Deschutes basin, central Oregon : a record of continental-margin volcanism and its influence on fluvial sedimentation in an arc-adjacent basin

  Neogene rocks of the Deschutes basin include the middle Miocene Columbia River Basalt Group and Simtustus Formation, and late Miocene to early Pliocene Deschutes Formation. Assignment of Prineville chemical-type ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphy, sedimentology, and petrology of neogene rocks in the Deschutes basin, central Oregon : a record of continental-margin volcanism and its influence on fluvial sedimentation in an arc-adjacent basin Author: Smith, Gary Allen Neogene rocks of the Deschutes basin include the middle Miocene Columbia River Basalt Group and Simtustus Formation, and late Miocene to early Pliocene Deschutes Formation. Assignment of Prineville chemical-type flows to the Grande Ronde Basalt of the Columbia River Basalt Group is based upon correlation of these lavas from their type area, through the Deschutes basin, and onto the Columbia Plateau where they have been previously mapped as Grande Ronde Basalt. Simtustus Formation is a newly defined unit intercalated with and conformable upon these basalts and is unconformably overlain by Deschutes Formation. Burial of mature topography by middle Miocene basalts raised local base levels and initiated aggradation by low-gradient streams within the basin represented by the tuffaceous sandstones and mudstones of the Simtustus Formation. These sediments are enriched in pyroclastic constituents relative to contemporary Western Cascades volcanics reflecting preferential incorporation of easily eroded and more widespread pyroclastic debris in distal sedimentary sequences compared to epiclastic contributions from lavas. Following a 5 to 7 m.y. hiatus, aggradation was renewed at about 7.5 Ma when coarse-grained volcanogenic sediments, lava flows and ignimbrites from the early High Cascades entered the basin for 2 m.y. The proximal Deschutes Formation is primarily basalt and basaltic andesite lava flows but andesite to rhyolite ignimbrites are the primary volcanic constitutents in the sedimentary-dominated section farther east. Deposition on a broad, eastward-tapering alluvial plain was by debris flows, sheetfloods, and hyperconcentrated flood flows. Episodic aggradation correlates to periods of sediment influx following eruptions' of widespread pyroclastic debris and was separated by periods of incision. The abundance of basalts, combined with the paucity of hydrous minerals and FeO and TiO₂ enrichment in intermediate lavas characterize early High Cascade yolcanics as atypical for convergent-margin arcs. These petrologic characteristics are consistent with high-level fractionation in an extensional regime. Extension culminated in the development of an intra-arc graben which ended Deschutes Formation deposition by structurally isolating the basin from the High Cascade source area. Intra-arc extension may represent invasion of Basin and Range tectonism into the Cascades, or may relate to plate-margin processes, particularly decreasing convergence rate and highly oblique convergence vector. Title: Stratigraphy, sedimentology, and petrology of neogene rocks in the Deschutes basin, central Oregon : a record of continental-margin volcanism and its influence on fluvial sedimentation in an arc-adjacent basin Author: Smith, Gary Allen Neogene rocks of the Deschutes basin include the middle Miocene Columbia River Basalt Group and Simtustus Formation, and late Miocene to early Pliocene Deschutes Formation. Assignment of Prineville chemical-type flows to the Grande Ronde Basalt of the Columbia River Basalt Group is based upon correlation of these lavas from their type area, through the Deschutes basin, and onto the Columbia Plateau where they have been previously mapped as Grande Ronde Basalt. Simtustus Formation is a newly defined unit intercalated with and conformable upon these basalts and is unconformably overlain by Deschutes Formation. Burial of mature topography by middle Miocene basalts raised local base levels and initiated aggradation by low-gradient streams within the basin represented by the tuffaceous sandstones and mudstones of the Simtustus Formation. These sediments are enriched in pyroclastic constituents relative to contemporary Western Cascades volcanics reflecting preferential incorporation of easily eroded and more widespread pyroclastic debris in distal sedimentary sequences compared to epiclastic contributions from lavas. Following a 5 to 7 m.y. hiatus, aggradation was renewed at about 7.5 Ma when coarse-grained volcanogenic sediments, lava flows and ignimbrites from the early High Cascades entered the basin for 2 m.y. The proximal Deschutes Formation is primarily basalt and basaltic andesite lava flows but andesite to rhyolite ignimbrites are the primary volcanic constitutents in the sedimentary-dominated section farther east. Deposition on a broad, eastward-tapering alluvial plain was by debris flows, sheetfloods, and hyperconcentrated flood flows. Episodic aggradation correlates to periods of sediment influx following eruptions' of widespread pyroclastic debris and was separated by periods of incision. The abundance of basalts, combined with the paucity of hydrous minerals and FeO and TiO₂ enrichment in intermediate lavas characterize early High Cascade yolcanics as atypical for convergent-margin arcs. These petrologic characteristics are consistent with high-level fractionation in an extensional regime. Extension culminated in the development of an intra-arc graben which ended Deschutes Formation deposition by structurally isolating the basin from the High Cascade source area. Intra-arc extension may represent invasion of Basin and Range tectonism into the Cascades, or may relate to plate-margin processes, particularly decreasing convergence rate and highly oblique convergence vector. Close

• 316. [Article] A terrestrial organic matter depocenter on a high-energy margin adjacent to a low-sediment-yield river : the Umpqua River margin, Oregon

  Small, mountainous river systems have been increasingly studied due to their importance as sources of fluvial sediment and organic matter to the coastal ocean. Thus far, studies of small, mountainous ...

  Citation × Citation Citation Abstract Copy Title: A terrestrial organic matter depocenter on a high-energy margin adjacent to a low-sediment-yield river : the Umpqua River margin, Oregon Author: Hastings, Roxanne H. Small, mountainous river systems have been increasingly studied due to their importance as sources of fluvial sediment and organic matter to the coastal ocean. Thus far, studies of small, mountainous river systems have focused on rivers with very high sediment loads. The well-studied Eel River dispersal system in northern California shares many characteristics with the Umpqua River system, but delivers ten times more sediment to the coastal ocean annually. These rivers deliver sediment and terrestrial organic matter during winter floods to a narrow, high-energy coastal margin. Studies of the Eel have shown that the formation of wave-supported gravity flows allows for the accumulation of sediment in a mid-shelf depocenter, and that without this transport mechanism, Eel River sediment is dispersed widely and exported off-shelf. The Umpqua margin is expected to be highly dispersive due to the energetic coastal ocean conditions and the low sediment supply, which is thought to be insufficient to trigger wave-supported gravity flows. Two-dimensional patterns in grain size and organic matter content and character from 66 surface sediment samples were examined to determine where fluvial material is deposited on the margin. The distribution of fine-grained sediment, organic matter and lignin phenols indicate a mid-shelf depocenter located from 85 to 115 m water depth stretching more than 40 km along-shelf on the Umpqua margin, which is unexpected. Organic matter within this depocenter is characterized by elemental OC:N ratios that range from 9.9 to 13.9, δ¹³C values that range from -22.2 ‰ to -24.2 ‰ and total lignin yields that range from 2.7 to 7.5 mg/100 mg OC all of which are consistent with a terrestrial source. A mixture of terrestrial and marine organic carbon is present on the outer shelf and upper slope indicating delivery of riverine material from the Umpqua shelf and distal rivers to the south. Comparisons of sedimentation rates, organic carbon content and size of the depocenters indicate that the Eel and Umpqua depocenters may bury similar quantities of organic carbon. These results suggest that organic matter burial may occur within depocenters on other margins influenced by rivers supplying moderate or low sediment loads. Title: A terrestrial organic matter depocenter on a high-energy margin adjacent to a low-sediment-yield river : the Umpqua River margin, Oregon Author: Hastings, Roxanne H. Small, mountainous river systems have been increasingly studied due to their importance as sources of fluvial sediment and organic matter to the coastal ocean. Thus far, studies of small, mountainous river systems have focused on rivers with very high sediment loads. The well-studied Eel River dispersal system in northern California shares many characteristics with the Umpqua River system, but delivers ten times more sediment to the coastal ocean annually. These rivers deliver sediment and terrestrial organic matter during winter floods to a narrow, high-energy coastal margin. Studies of the Eel have shown that the formation of wave-supported gravity flows allows for the accumulation of sediment in a mid-shelf depocenter, and that without this transport mechanism, Eel River sediment is dispersed widely and exported off-shelf. The Umpqua margin is expected to be highly dispersive due to the energetic coastal ocean conditions and the low sediment supply, which is thought to be insufficient to trigger wave-supported gravity flows. Two-dimensional patterns in grain size and organic matter content and character from 66 surface sediment samples were examined to determine where fluvial material is deposited on the margin. The distribution of fine-grained sediment, organic matter and lignin phenols indicate a mid-shelf depocenter located from 85 to 115 m water depth stretching more than 40 km along-shelf on the Umpqua margin, which is unexpected. Organic matter within this depocenter is characterized by elemental OC:N ratios that range from 9.9 to 13.9, δ¹³C values that range from -22.2 ‰ to -24.2 ‰ and total lignin yields that range from 2.7 to 7.5 mg/100 mg OC all of which are consistent with a terrestrial source. A mixture of terrestrial and marine organic carbon is present on the outer shelf and upper slope indicating delivery of riverine material from the Umpqua shelf and distal rivers to the south. Comparisons of sedimentation rates, organic carbon content and size of the depocenters indicate that the Eel and Umpqua depocenters may bury similar quantities of organic carbon. These results suggest that organic matter burial may occur within depocenters on other margins influenced by rivers supplying moderate or low sediment loads. Close

• 317. [Article] Municipal sewerage system resilience : disturbances and management strategies in Cook County, IL

  Sewerage infrastructure, including wastewater treatment facilities and conveyance pipes, is reaching the end of its useful life throughout the United States. Aging infrastructure may be more susceptible ...

  Citation × Citation Citation Abstract Copy Title: Municipal sewerage system resilience : disturbances and management strategies in Cook County, IL Author: Oravec, Timothy J. Sewerage infrastructure, including wastewater treatment facilities and conveyance pipes, is reaching the end of its useful life throughout the United States. Aging infrastructure may be more susceptible to fracturing and collapses due to deterioration. Further, sewerage infrastructure is usually designed to discharge untreated wastewater or stormwater into nearby waterways during intense wet-weather events, potentially contributing to environmental and public health concerns. Upgrading or replacing sewerage infrastructure often requires major construction projects that can be burdensome for municipalities. This study examines municipal sewerage infrastructure as part of a system with technical, administrative, social, economic, and environmental dimensions. Important disturbances and management strategies affecting municipal sewerage systems in Cook County, Illinois were identified through semi-structured interviews with Public Works and Engineering department professionals. Interviews were then analyzed using resilience theory, attending to system robustness, redundancy, resourcefulness, and rapidity. As the vast majority of literature indicates, findings suggest that managers of municipal sewer systems in Cook County are most concerned with maintenance of technical infrastructure, which is largely limited by economic constraints: unpredictable and decreasing financial resources, coupled with the high cost of repair projects. Interviewees from wealthier communities generally demonstrated less concern about current funding for sewerage infrastructure projects, although many expressed concern that they will not be able to sustain their current level of investment. Most interviewees also suggested concern with the lack of residents’ knowledge about sewerage systems and engagement in the management process, often leading to widespread basement flooding and consternation among residents. Interviews highlighted relationships between the robustness, redundancy, resourcefulness, and rapidity of many technical, administrative, social, economic, and environmental dimensions; that is, attempts to manage for specific system attributes can have direct and, often, predictable effects on other attributes within the sewerage system. Title: Municipal sewerage system resilience : disturbances and management strategies in Cook County, IL Author: Oravec, Timothy J. Sewerage infrastructure, including wastewater treatment facilities and conveyance pipes, is reaching the end of its useful life throughout the United States. Aging infrastructure may be more susceptible to fracturing and collapses due to deterioration. Further, sewerage infrastructure is usually designed to discharge untreated wastewater or stormwater into nearby waterways during intense wet-weather events, potentially contributing to environmental and public health concerns. Upgrading or replacing sewerage infrastructure often requires major construction projects that can be burdensome for municipalities. This study examines municipal sewerage infrastructure as part of a system with technical, administrative, social, economic, and environmental dimensions. Important disturbances and management strategies affecting municipal sewerage systems in Cook County, Illinois were identified through semi-structured interviews with Public Works and Engineering department professionals. Interviews were then analyzed using resilience theory, attending to system robustness, redundancy, resourcefulness, and rapidity. As the vast majority of literature indicates, findings suggest that managers of municipal sewer systems in Cook County are most concerned with maintenance of technical infrastructure, which is largely limited by economic constraints: unpredictable and decreasing financial resources, coupled with the high cost of repair projects. Interviewees from wealthier communities generally demonstrated less concern about current funding for sewerage infrastructure projects, although many expressed concern that they will not be able to sustain their current level of investment. Most interviewees also suggested concern with the lack of residents’ knowledge about sewerage systems and engagement in the management process, often leading to widespread basement flooding and consternation among residents. Interviews highlighted relationships between the robustness, redundancy, resourcefulness, and rapidity of many technical, administrative, social, economic, and environmental dimensions; that is, attempts to manage for specific system attributes can have direct and, often, predictable effects on other attributes within the sewerage system. Close

• 318. [Article] Activity recognition in desktop environments

  Knowledge workers are struggling in the information flood. There is a growing interest in intelligent desktop environments that help knowledge workers organize their daily life. Intelligent desktop environments ...

  Citation × Citation Citation Abstract Copy Title: Activity recognition in desktop environments Author: Shen, Jianqiang Knowledge workers are struggling in the information flood. There is a growing interest in intelligent desktop environments that help knowledge workers organize their daily life. Intelligent desktop environments allow the desktop user to define a set of “activities” that characterize the user’s desktop work. These environments then attempt to identify the current activity of the user in order to provide various kinds of assistance. TaskTracer is one of these efforts. We classify activities into three levels: “task” as in TaskTracer, workflow, and operation. In this thesis, we concentrate on the two higher levels of activity – “task” and “workflow” -- and we present an activity recognition solution for each of them. To recognize tasks, we employ various supervised learning algorithms. The first approach is based on batch training, which has a heavy requirement for CPU time and memory. It is also insensitive to the user feedback, and it is likely to make repeated mistakes. To address these issues, we propose a novel online learning algorithm that is able to incorporate a richer set of features than our previous predictors. We prove an error bound for the algorithm and present experimental results that show improved accuracy and a 180-fold speedup on real user data. To recognize workflows, we first mine frequent workflow models from the TaskTracer event log. Discovering desktop workflows is difficult because they unfold over extended periods of time (days or weeks) and they are interleaved with many other workflows because of user multi-tasking. We describe an approach to discovering desktop workflows based on rich instrumentation of information flow actions such as copy/paste, SaveAs, file copy, attach file to email message, and save attachment. These actions allow us to construct a graph whose nodes are files, email messages, and web pages and whose edges are these information flow actions. A class of workflows that we call work procedures can be discovered by applying graph mining algorithms to find frequent subgraphs. After finding the workflow models, we create a Logical Hidden Markov Model (LHMM) for each mined model to represent the workflow in a form suitable for real-time recognition using the WARP relational inference algorithm. Title: Activity recognition in desktop environments Author: Shen, Jianqiang Knowledge workers are struggling in the information flood. There is a growing interest in intelligent desktop environments that help knowledge workers organize their daily life. Intelligent desktop environments allow the desktop user to define a set of “activities” that characterize the user’s desktop work. These environments then attempt to identify the current activity of the user in order to provide various kinds of assistance. TaskTracer is one of these efforts. We classify activities into three levels: “task” as in TaskTracer, workflow, and operation. In this thesis, we concentrate on the two higher levels of activity – “task” and “workflow” -- and we present an activity recognition solution for each of them. To recognize tasks, we employ various supervised learning algorithms. The first approach is based on batch training, which has a heavy requirement for CPU time and memory. It is also insensitive to the user feedback, and it is likely to make repeated mistakes. To address these issues, we propose a novel online learning algorithm that is able to incorporate a richer set of features than our previous predictors. We prove an error bound for the algorithm and present experimental results that show improved accuracy and a 180-fold speedup on real user data. To recognize workflows, we first mine frequent workflow models from the TaskTracer event log. Discovering desktop workflows is difficult because they unfold over extended periods of time (days or weeks) and they are interleaved with many other workflows because of user multi-tasking. We describe an approach to discovering desktop workflows based on rich instrumentation of information flow actions such as copy/paste, SaveAs, file copy, attach file to email message, and save attachment. These actions allow us to construct a graph whose nodes are files, email messages, and web pages and whose edges are these information flow actions. A class of workflows that we call work procedures can be discovered by applying graph mining algorithms to find frequent subgraphs. After finding the workflow models, we create a Logical Hidden Markov Model (LHMM) for each mined model to represent the workflow in a form suitable for real-time recognition using the WARP relational inference algorithm. Close

• 319. [Article] Fish and amphibian use of intermittent streams within the upper Willamette Basin, Oregon

  In the fall through spring of 2002/03 and 2003/04, the composition of fish and amphibian communities were examined in intermittent streams in the upper Willamette river basin in western Oregon. I recorded ...

  Citation × Citation Citation Abstract Copy Title: Fish and amphibian use of intermittent streams within the upper Willamette Basin, Oregon Author: Colvin, Randall William In the fall through spring of 2002/03 and 2003/04, the composition of fish and amphibian communities were examined in intermittent streams in the upper Willamette river basin in western Oregon. I recorded standard aquatic habitat variables and water nutrient concentrations (nitrate and phosphate) and correlated them with fish and amphibian communities present. Fish and amphibian communities were also compared between seasons (winter and spring), capture method (minnowtrap and backpack electrofishing) and channel morphology (incised and gently sloping channels). Fish were tagged with visual implant elastomer to assess movement and distribution. Fourteen species of fish and five species of amphibians were present in these habitats over two field seasons. Fish and amphibian species composition and abundance was correlated with characteristics of the upper Willamette basin. The regional characteristics associated with the differences were a) the amount of the watershed covered in forest and b) upstream slope; whereas mean maximum water velocity separated fish dominated communities from amphibian dominated communities. Approximately 99% of fish and amphibian species caught were native to the Willamette river basin and the number of fish species decreased as the sampling distance from perennial water increased. Significant differences were found in fish and amphibian community composition between winter and spring and between capture methods. Surface/mid-water feeding fish were more abundant in gently sloping channels than benthic feeding fishes. Only 2.6% of the 498 tagged fish were recaptured between December and April. In the fall through spring 2003/04, the composition of fish communities and their invertebrate diets were compared between 12 sites on four intermittent streams. The distance between consecutive sites was approximately 900 to 1500-m. Two intermittent streams had incised channels, confining high flows to a narrow channel. The remaining two streams had gently sloping channels, where flood waters had access to the floodplain. Two hundred and thirty individual diets were sampled from cutthroat trout, northern pikeminnow, redside shiner, sculpin, speckled dace, threespine stickleback in both winter and spring. About 60% of the stomach samples contained invertebrates and approximately 90% of them were aquatic species. There was a significant difference in the numbers of invertebrates consumed by redside shiners, sculpins and speckled dace. These three fish species fed most often on benthic invertebrates compared to surf ace/midwater invertebrates, but only sculpins and redside shiners were significantly different. However, the proportions of benthic and surface/midwater invertebrates in the diet of these fish species were not significantly different between seasons or channel types. This thesis inventories fish and amphibian species found in intermittent stream habitats of the upper Willamette basin, and identifies the main habitat features that influence the distribution of those species. It also examines the diet composition of a subset of widely distributed fish species. The findings of this study can be used to understand how land uses, such as grass seed agriculture, affect intermittent streams, and to design future studies on the effectiveness of habitat enhancement conservation practices (such as grassed waterways, residue management, filter strips, streambank protection, etc.) to improve and/or protect these important seasonal habitats in the upper Willamette basin. Title: Fish and amphibian use of intermittent streams within the upper Willamette Basin, Oregon Author: Colvin, Randall William In the fall through spring of 2002/03 and 2003/04, the composition of fish and amphibian communities were examined in intermittent streams in the upper Willamette river basin in western Oregon. I recorded standard aquatic habitat variables and water nutrient concentrations (nitrate and phosphate) and correlated them with fish and amphibian communities present. Fish and amphibian communities were also compared between seasons (winter and spring), capture method (minnowtrap and backpack electrofishing) and channel morphology (incised and gently sloping channels). Fish were tagged with visual implant elastomer to assess movement and distribution. Fourteen species of fish and five species of amphibians were present in these habitats over two field seasons. Fish and amphibian species composition and abundance was correlated with characteristics of the upper Willamette basin. The regional characteristics associated with the differences were a) the amount of the watershed covered in forest and b) upstream slope; whereas mean maximum water velocity separated fish dominated communities from amphibian dominated communities. Approximately 99% of fish and amphibian species caught were native to the Willamette river basin and the number of fish species decreased as the sampling distance from perennial water increased. Significant differences were found in fish and amphibian community composition between winter and spring and between capture methods. Surface/mid-water feeding fish were more abundant in gently sloping channels than benthic feeding fishes. Only 2.6% of the 498 tagged fish were recaptured between December and April. In the fall through spring 2003/04, the composition of fish communities and their invertebrate diets were compared between 12 sites on four intermittent streams. The distance between consecutive sites was approximately 900 to 1500-m. Two intermittent streams had incised channels, confining high flows to a narrow channel. The remaining two streams had gently sloping channels, where flood waters had access to the floodplain. Two hundred and thirty individual diets were sampled from cutthroat trout, northern pikeminnow, redside shiner, sculpin, speckled dace, threespine stickleback in both winter and spring. About 60% of the stomach samples contained invertebrates and approximately 90% of them were aquatic species. There was a significant difference in the numbers of invertebrates consumed by redside shiners, sculpins and speckled dace. These three fish species fed most often on benthic invertebrates compared to surf ace/midwater invertebrates, but only sculpins and redside shiners were significantly different. However, the proportions of benthic and surface/midwater invertebrates in the diet of these fish species were not significantly different between seasons or channel types. This thesis inventories fish and amphibian species found in intermittent stream habitats of the upper Willamette basin, and identifies the main habitat features that influence the distribution of those species. It also examines the diet composition of a subset of widely distributed fish species. The findings of this study can be used to understand how land uses, such as grass seed agriculture, affect intermittent streams, and to design future studies on the effectiveness of habitat enhancement conservation practices (such as grassed waterways, residue management, filter strips, streambank protection, etc.) to improve and/or protect these important seasonal habitats in the upper Willamette basin. Close

• 320. [Article] A novel framework for uncertainty propagation in river systems based on performance graphs using two-dimensional hydrodynamic modeling

  This thesis presents a novel approach for propagation of uncertainty in river systems. Errors in data observations and predictions (e.g., stream inflows), in model parameters, and resulting from the discretization ...

  Citation × Citation Citation Abstract Copy Title: A novel framework for uncertainty propagation in river systems based on performance graphs using two-dimensional hydrodynamic modeling Author: Gifford-Miears, Christopher H. This thesis presents a novel approach for propagation of uncertainty in river systems. Errors in data observations and predictions (e.g., stream inflows), in model parameters, and resulting from the discretization of continuous systems, all point to the need to accurately quantify the amount of uncertainty carried through the modeling process. In the proposed framework, stochastic processes are incorporated directly into the physical description of the system (e.g., river flow dynamics) with the goal of better modeling uncertainties (both aleatoric and epistemic) and hence, reducing the ranges of the confidence intervals on quantities of interest. We represent uncertainty in stream inflows via an error term modeled as a stochastic process. Stochastic collocation is then used to discretize random space. This non-intrusive approach is both more efficient than Monte-Carlo methods and is as flexible in its application. The flow dynamics are simulated efficiently using the performance graphs approach implemented in the OSU Rivers model. For one-dimensional unsteady flow routing, the performance graph (PG) approach has been shown to be accurate, numerically efficient, and robust. The Hydraulic Performance Graph (HPG) of a channel reach graphically summarizes the dynamic relation between the flow through and the stages at the ends of the reach under gradually varied flow (GVF) conditions, while the Volumetric Performance Graph (VPG) summarizes the corresponding storage. The hydraulic routing for the entire system consists of dividing the river system into reaches and pre-computing the hydraulics for each of these reaches independently using a steady flow model. Then, a non-linear system of equations is solved that is assembled based on information summarized in the systems' performance graphs, the reach-wise equation of conservation of mass, continuity and water stage compatibility conditions at the union of reaches (nodes), and the system boundary conditions. For complex flows in river systems such as when there is flow over floodplains, the dynamic relation between water stages and flow in a river reach is best represented by depth averaged two-dimensional hydrodynamic models. The applicability of two-dimensional flow modeling for the construction of PGs for unsteady flow routing in complex river networks is explored. To illustrate application of the uncertainty propagation framework and PGs derived from two-dimensional flow models, a test case is presented that examines uncertainty quantification and flood routing through a complex section of the Fraser River in British Columbia. Title: A novel framework for uncertainty propagation in river systems based on performance graphs using two-dimensional hydrodynamic modeling Author: Gifford-Miears, Christopher H. This thesis presents a novel approach for propagation of uncertainty in river systems. Errors in data observations and predictions (e.g., stream inflows), in model parameters, and resulting from the discretization of continuous systems, all point to the need to accurately quantify the amount of uncertainty carried through the modeling process. In the proposed framework, stochastic processes are incorporated directly into the physical description of the system (e.g., river flow dynamics) with the goal of better modeling uncertainties (both aleatoric and epistemic) and hence, reducing the ranges of the confidence intervals on quantities of interest. We represent uncertainty in stream inflows via an error term modeled as a stochastic process. Stochastic collocation is then used to discretize random space. This non-intrusive approach is both more efficient than Monte-Carlo methods and is as flexible in its application. The flow dynamics are simulated efficiently using the performance graphs approach implemented in the OSU Rivers model. For one-dimensional unsteady flow routing, the performance graph (PG) approach has been shown to be accurate, numerically efficient, and robust. The Hydraulic Performance Graph (HPG) of a channel reach graphically summarizes the dynamic relation between the flow through and the stages at the ends of the reach under gradually varied flow (GVF) conditions, while the Volumetric Performance Graph (VPG) summarizes the corresponding storage. The hydraulic routing for the entire system consists of dividing the river system into reaches and pre-computing the hydraulics for each of these reaches independently using a steady flow model. Then, a non-linear system of equations is solved that is assembled based on information summarized in the systems' performance graphs, the reach-wise equation of conservation of mass, continuity and water stage compatibility conditions at the union of reaches (nodes), and the system boundary conditions. For complex flows in river systems such as when there is flow over floodplains, the dynamic relation between water stages and flow in a river reach is best represented by depth averaged two-dimensional hydrodynamic models. The applicability of two-dimensional flow modeling for the construction of PGs for unsteady flow routing in complex river networks is explored. To illustrate application of the uncertainty propagation framework and PGs derived from two-dimensional flow models, a test case is presented that examines uncertainty quantification and flood routing through a complex section of the Fraser River in British Columbia. Close