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• 51. [Article] AI - Restoration Effectiveness Monitoring Plan for the Western Oregon Stream Project; Monitoring through June 2008

  Abstract -- The purpose of this plan is to outline the continued monitoring of stream restoration work completed as part of the Western Oregon Stream Project. This revised plan has been developed out of ...

  Citation × Citation Citation Abstract Copy Title: AI - Restoration Effectiveness Monitoring Plan for the Western Oregon Stream Project; Monitoring through June 2008 Abstract -- The purpose of this plan is to outline the continued monitoring of stream restoration work completed as part of the Western Oregon Stream Project. This revised plan has been developed out of a need to monitor a subset of restoratio n projects from all areas of the Western Oregon Stream Project (Figure 1). This plan encompasses the monitoring period of January 2000 to June 2008, and is a continuation of monitoring activities that were started in the fall of 1995 on the North Coast and continued into the Mid-coast in 1996 and 1997. Much of this plan is a compilation of the original North Coast and Mid-Coast monitoring plans (Hodgson 1996, Thom and Moore 1995). Modifications have been made to better define the monitoring activities, increase efficiency, and strengthen the scientific credibility of the project. Four main questions will be answered as a result of the monitoring activities outlined in this plan. They are: 1)How much stream restoration work has been completed? 2)Is the stream restoration work that is completed leading to improved habitat conditions for salmonids in the treated stream reaches? 3)What fish are utilizing the restored habitats? 4)What are the trends in juvenile abundance in the restored stream reaches? Title: AI - Restoration Effectiveness Monitoring Plan for the Western Oregon Stream Project; Monitoring through June 2008 Abstract -- The purpose of this plan is to outline the continued monitoring of stream restoration work completed as part of the Western Oregon Stream Project. This revised plan has been developed out of a need to monitor a subset of restoratio n projects from all areas of the Western Oregon Stream Project (Figure 1). This plan encompasses the monitoring period of January 2000 to June 2008, and is a continuation of monitoring activities that were started in the fall of 1995 on the North Coast and continued into the Mid-coast in 1996 and 1997. Much of this plan is a compilation of the original North Coast and Mid-Coast monitoring plans (Hodgson 1996, Thom and Moore 1995). Modifications have been made to better define the monitoring activities, increase efficiency, and strengthen the scientific credibility of the project. Four main questions will be answered as a result of the monitoring activities outlined in this plan. They are: 1)How much stream restoration work has been completed? 2)Is the stream restoration work that is completed leading to improved habitat conditions for salmonids in the treated stream reaches? 3)What fish are utilizing the restored habitats? 4)What are the trends in juvenile abundance in the restored stream reaches? Close

• 52. [Article] Stream*A*Syst : a tool to help you examine stream conditions on your property

  Published October 2007. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cata...

  Citation × Citation Citation Abstract Copy Title: Stream*A*Syst : a tool to help you examine stream conditions on your property Author: Andrews, Gail Glick, Oregon State University. Extension Service Published October 2007. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Stream*A*Syst : a tool to help you examine stream conditions on your property Author: Andrews, Gail Glick, Oregon State University. Extension Service Published October 2007. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 53. [Article] Evaluation of stream temperature spatial variation using distributed temperature sensing

  Water temperature in rivers and streams is an important factor for aquatic ecosystem health. Measurement of stream temperature has traditionally been accomplished by point temperature measurements, continuous ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of stream temperature spatial variation using distributed temperature sensing Author: O'Donnell, Tara Water temperature in rivers and streams is an important factor for aquatic ecosystem health. Measurement of stream temperature has traditionally been accomplished by point temperature measurements, continuous point temperature loggers, and more recently, airborne remote sensing techniques such as Forward-Looking Infrared Radar (FLIR) or Thermal Infrared Radiometry. While each of these measurement techniques has certain advantages, none allows for the combined spatial and temporal information provided by Distributed Temperature Sensing (DTS). DTS employs fiber optic signals to measure temperature and is a relatively new temperature measurement technology for hydrologic sensing applications. Nine DTS stream temperature datasets were collected in the Middle Fork John Day River (MFJDR) as part of a basin-wide stream monitoring effort. The datasets encompassed five 1-3 kilometer long reaches, some monitored over three summers (2009-2011). In contrast to existing stream temperature measurement technologies, DTS can provide stream temperature data in both the spatial and temporal domains. Techniques and challenges of interpreting DTS stream temperature data were documented, and three applications of the technology to stream temperature monitoring were explored. Cold water patches, potentially used by fish as thermal refugia during stream temperature maximums, were located using DTS. No identified cold patch exceeded 2.31°C cooler than ambient stream temperature. Tributary inflows provided some of the most temperature-differentiated cold patches. These findings provide a reference for the degree of thermal heterogeneity in the MFJDR system and beg the question of whether fish respond to small (<3°C) spatial temperature variations. Theoretical predictions of stream mixing potential (Richardson number and cavity flow mixing predictions) suggested that increasing stream thermal heterogeneity would require channel modification to decrease stream flow velocity in select areas. The combined spatial and temporal coverage of a DTS stream temperature dataset on the Oxbow Conservation Area allowed diagnosis of a 2°C longitudinal stream temperature decrease observed in multiple Thermal Infrared Radiometry (TIR) and Forward-Looking Infrared Radiometry (FLIR) datasets collected on that reach. Advection velocity and channel depth, rather than groundwater or tributary inflows, were the main cause of the decrease, and the magnitude of the decrease peaked in the early afternoon, disappearing completely by evening. This finding suggests caution for interpretation of FLIR and TIR stream temperature datasets, which represent "snapshot" temperature measurements. For these datasets, knowledge of flow conditions (velocity and depth) may help avoid misinterpretation of temporally-transient temperature anomalies. Diurnal slope periodicity was observed in linear-like spatial trends in four DTS datasets, and an analysis was made to examine this subtle spatially and temporally varying phenomenon. The phase of the diurnal slope variation differed between river reaches, suggesting that propagation of larger-scale thermal waves might be one driving mechanism. Temporally-constant offsets between slope magnitudes within reaches suggested some intra-reach differences in heat fluxes. Title: Evaluation of stream temperature spatial variation using distributed temperature sensing Author: O'Donnell, Tara Water temperature in rivers and streams is an important factor for aquatic ecosystem health. Measurement of stream temperature has traditionally been accomplished by point temperature measurements, continuous point temperature loggers, and more recently, airborne remote sensing techniques such as Forward-Looking Infrared Radar (FLIR) or Thermal Infrared Radiometry. While each of these measurement techniques has certain advantages, none allows for the combined spatial and temporal information provided by Distributed Temperature Sensing (DTS). DTS employs fiber optic signals to measure temperature and is a relatively new temperature measurement technology for hydrologic sensing applications. Nine DTS stream temperature datasets were collected in the Middle Fork John Day River (MFJDR) as part of a basin-wide stream monitoring effort. The datasets encompassed five 1-3 kilometer long reaches, some monitored over three summers (2009-2011). In contrast to existing stream temperature measurement technologies, DTS can provide stream temperature data in both the spatial and temporal domains. Techniques and challenges of interpreting DTS stream temperature data were documented, and three applications of the technology to stream temperature monitoring were explored. Cold water patches, potentially used by fish as thermal refugia during stream temperature maximums, were located using DTS. No identified cold patch exceeded 2.31°C cooler than ambient stream temperature. Tributary inflows provided some of the most temperature-differentiated cold patches. These findings provide a reference for the degree of thermal heterogeneity in the MFJDR system and beg the question of whether fish respond to small (<3°C) spatial temperature variations. Theoretical predictions of stream mixing potential (Richardson number and cavity flow mixing predictions) suggested that increasing stream thermal heterogeneity would require channel modification to decrease stream flow velocity in select areas. The combined spatial and temporal coverage of a DTS stream temperature dataset on the Oxbow Conservation Area allowed diagnosis of a 2°C longitudinal stream temperature decrease observed in multiple Thermal Infrared Radiometry (TIR) and Forward-Looking Infrared Radiometry (FLIR) datasets collected on that reach. Advection velocity and channel depth, rather than groundwater or tributary inflows, were the main cause of the decrease, and the magnitude of the decrease peaked in the early afternoon, disappearing completely by evening. This finding suggests caution for interpretation of FLIR and TIR stream temperature datasets, which represent "snapshot" temperature measurements. For these datasets, knowledge of flow conditions (velocity and depth) may help avoid misinterpretation of temporally-transient temperature anomalies. Diurnal slope periodicity was observed in linear-like spatial trends in four DTS datasets, and an analysis was made to examine this subtle spatially and temporally varying phenomenon. The phase of the diurnal slope variation differed between river reaches, suggesting that propagation of larger-scale thermal waves might be one driving mechanism. Temporally-constant offsets between slope magnitudes within reaches suggested some intra-reach differences in heat fluxes. Close

• 54. [Article] Reaeration in a turbulent stream system

  The oxygen concentration in a stream is an important parameter of water quality. Changes in oxygen concentrations can affect various stream organisms including fish. Foresters have become concerned with ...

  Citation × Citation Citation Abstract Copy Title: Reaeration in a turbulent stream system Author: Ice, George G. The oxygen concentration in a stream is an important parameter of water quality. Changes in oxygen concentrations can affect various stream organisms including fish. Foresters have become concerned with predicting the impacts of forest activities on oxygen levels in streams. Slash, which accumulates in streams as a result of harvesting activities, is a food source for stream organisms. During aerobic respiration, oxygen is utilized. Under some conditions the oxygen concentration can be depleted below acceptable levels. Large, fish bearing streams are generally well protected by forest practice regulations. For smaller streams without fish populations, the issue is one of downstream impairment of water quality as deoxygenated water enters fish-bearing reaches. A natural process counteracting oxygen depletion is reaeration. Reaeration is the exchange of gases between the atmosphere and water. This process operates to maintain oxygen near the saturation concentration. The change in the oxygen deficit in a stream is a function of the existing deficit and the reaeration rate coefficient. The objective of this study was to develop a predictive equation for the reaeration rate coefficient based on the hydraulic characteristics of stream channels. This is a a first step in developing guidelines to regulate harvesting residues in streams. Seven natural stream sites were selected in Oregon. These sites represented a wide range of hydraulic conditions. The stream reaches were segregated into segments of uniform hydraulic characteristics. Sodium sulfite was injected into the stream to artificially deplete the oxygen concentration. The recovery of the oxygen concentration was used to determine the reaeration rate coefficient. Several models for the reaeration process were tested using regression techniques. Some were models proposed by other investigators and some were developed independently. The predictive equation which fit the data best is a function of the maximum unit energy dissipation rate (ED) and a depth parameter (HD): [equation-see PDF] This equation is consistent with theoretical descriptions of gas exchange phenomena. As the rate of energy dissipation increases in a segment, the turbulence in the segment also increases. Turbulence promotes an increase in the liquid-atmosphere interface area and in the exchange rate of volume elements in the interface. Reaeration is stimulated when deaerated water from the bulk flow of the stream replaces the oxygen saturated water in the surface film. As the area of liquid-atmosphere contact increases, the total flux of oxygen molecules into the depleted fluid volume increases. As the fluid volume increases, the change in concentration for a specific flux of molecules decreases. The depth term (HD) can be used to describe the ratio of the surface area to the volume of fluid in the segment. In this study, the depth term used was the discharge divided by the mean width and maximum velocity. This approach adjusts for dead zones that do not actively mix with the bulk flow. For field applications, predicting the reaeration coefficient for any temperature (T) requires that the slope (s), active width (WD), maximum velocity (UD), and discharge (Q), be measured for uniform stream segments. These variables are combined in the following equation: [equation- see PDF] Using the predicted reaeration rates, estimates of mean segment velocities, biochemical oxygen demand loading, and rates of oxygen demand decay, it is possible to predict the oxygen concentration of a stream moving through and downstream from a harvesting site. The reaeration rate influences the maximum deficit and time required for recovery and can be used to evaluate the risks that debris accumulations pose to water quality. Title: Reaeration in a turbulent stream system Author: Ice, George G. The oxygen concentration in a stream is an important parameter of water quality. Changes in oxygen concentrations can affect various stream organisms including fish. Foresters have become concerned with predicting the impacts of forest activities on oxygen levels in streams. Slash, which accumulates in streams as a result of harvesting activities, is a food source for stream organisms. During aerobic respiration, oxygen is utilized. Under some conditions the oxygen concentration can be depleted below acceptable levels. Large, fish bearing streams are generally well protected by forest practice regulations. For smaller streams without fish populations, the issue is one of downstream impairment of water quality as deoxygenated water enters fish-bearing reaches. A natural process counteracting oxygen depletion is reaeration. Reaeration is the exchange of gases between the atmosphere and water. This process operates to maintain oxygen near the saturation concentration. The change in the oxygen deficit in a stream is a function of the existing deficit and the reaeration rate coefficient. The objective of this study was to develop a predictive equation for the reaeration rate coefficient based on the hydraulic characteristics of stream channels. This is a a first step in developing guidelines to regulate harvesting residues in streams. Seven natural stream sites were selected in Oregon. These sites represented a wide range of hydraulic conditions. The stream reaches were segregated into segments of uniform hydraulic characteristics. Sodium sulfite was injected into the stream to artificially deplete the oxygen concentration. The recovery of the oxygen concentration was used to determine the reaeration rate coefficient. Several models for the reaeration process were tested using regression techniques. Some were models proposed by other investigators and some were developed independently. The predictive equation which fit the data best is a function of the maximum unit energy dissipation rate (ED) and a depth parameter (HD): [equation-see PDF] This equation is consistent with theoretical descriptions of gas exchange phenomena. As the rate of energy dissipation increases in a segment, the turbulence in the segment also increases. Turbulence promotes an increase in the liquid-atmosphere interface area and in the exchange rate of volume elements in the interface. Reaeration is stimulated when deaerated water from the bulk flow of the stream replaces the oxygen saturated water in the surface film. As the area of liquid-atmosphere contact increases, the total flux of oxygen molecules into the depleted fluid volume increases. As the fluid volume increases, the change in concentration for a specific flux of molecules decreases. The depth term (HD) can be used to describe the ratio of the surface area to the volume of fluid in the segment. In this study, the depth term used was the discharge divided by the mean width and maximum velocity. This approach adjusts for dead zones that do not actively mix with the bulk flow. For field applications, predicting the reaeration coefficient for any temperature (T) requires that the slope (s), active width (WD), maximum velocity (UD), and discharge (Q), be measured for uniform stream segments. These variables are combined in the following equation: [equation- see PDF] Using the predicted reaeration rates, estimates of mean segment velocities, biochemical oxygen demand loading, and rates of oxygen demand decay, it is possible to predict the oxygen concentration of a stream moving through and downstream from a harvesting site. The reaeration rate influences the maximum deficit and time required for recovery and can be used to evaluate the risks that debris accumulations pose to water quality. Close

• 55. [Article] Effects of logging on the growth of juvenile coho salmon

  The objective of this research was to study the effects of increased water temperature characteristic of clearcut watersheds of Pacific coastal streams upon the growth rate of juvenile coho salmon. The ...

  Citation × Citation Citation Abstract Copy Title: Effects of logging on the growth of juvenile coho salmon Author: Iwanaga, Paul M. The objective of this research was to study the effects of increased water temperature characteristic of clearcut watersheds of Pacific coastal streams upon the growth rate of juvenile coho salmon. The natural temperature fluctuations of the stream were used in the study of growth of underyearling fish held in aquariums and fed at various consumption levels. Juvenile coho experiencing the cooler temperatures of the control stream demonstrated generally better growth rates than did those that experienced the warmer temperatures of the clearcut stream. The reduced maintenance requirements in the control experiment indicated a reduced basal metabolic demand, which allowed for a greater portion of the food consumed to be utilized for growth. This was particularly true at low levels of consumption. Growth rates of juvenile coho salmon in the wild state were found to be higher in the logged stream as compared to the unlogged stream. This difference from the experimental results is thought to be due to a change in availability and abundance of food. There was a marked decrease in the cutthroat trout population in the clearcut stream, which may have reduced competition for the coho salmon. Increased exposure of the stream to solar radiation also may have permitted en increase in primary production essential for small organisms upon which the juvenile coho feed. There was no apparent influence of infestation by salmon poisoning fluke on the condition of the juvenile coho. Title: Effects of logging on the growth of juvenile coho salmon Author: Iwanaga, Paul M. The objective of this research was to study the effects of increased water temperature characteristic of clearcut watersheds of Pacific coastal streams upon the growth rate of juvenile coho salmon. The natural temperature fluctuations of the stream were used in the study of growth of underyearling fish held in aquariums and fed at various consumption levels. Juvenile coho experiencing the cooler temperatures of the control stream demonstrated generally better growth rates than did those that experienced the warmer temperatures of the clearcut stream. The reduced maintenance requirements in the control experiment indicated a reduced basal metabolic demand, which allowed for a greater portion of the food consumed to be utilized for growth. This was particularly true at low levels of consumption. Growth rates of juvenile coho salmon in the wild state were found to be higher in the logged stream as compared to the unlogged stream. This difference from the experimental results is thought to be due to a change in availability and abundance of food. There was a marked decrease in the cutthroat trout population in the clearcut stream, which may have reduced competition for the coho salmon. Increased exposure of the stream to solar radiation also may have permitted en increase in primary production essential for small organisms upon which the juvenile coho feed. There was no apparent influence of infestation by salmon poisoning fluke on the condition of the juvenile coho. Close

• 56. [Article] Historical changes in stream habitats in the Columbia River basin

  Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current ...

  Citation × Citation Citation Abstract Copy Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Close

• 57. [Article] Optimization of Flexible Dual-TCP/UDP Streaming Protocol For HD Video Streaming over 802.11 Wireless Networks

  Flexible Dual-TCP/UDP Streaming Protocol with Adaptive Bitstream Prioritization (FDSP with Adaptive-BP) is a new method for streaming H.264-encoded High-definition (HD) video over WLANs. Traditionally, ...

  Citation × Citation Citation Abstract Copy Title: Optimization of Flexible Dual-TCP/UDP Streaming Protocol For HD Video Streaming over 802.11 Wireless Networks Author: Dhamodaran, Arul N. Flexible Dual-TCP/UDP Streaming Protocol with Adaptive Bitstream Prioritization (FDSP with Adaptive-BP) is a new method for streaming H.264-encoded High-definition (HD) video over WLANs. Traditionally, video streaming is done either using Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) protocol, resulting in either rebuffering or packet loss respectively. While FDSP-based streaming addresses these issues, it experiences a new set of problems as it incurs both packet loss and re- buffering. This makes the actual Quality of Experience (QoE) delivered to end-users one of the key criteria in the Adaptive-BP selection process. As such, this paper presents an analysis of the subjective impact of both packet loss and rebuffering on video streaming quality as perceived by the end-user. Our QoE study focuses on identifying the threshold limits of both packet loss and rebuffering for the different Mean Opinion Score (MOS) ranges, which can then be applied to the Adaptive-BP algorithm to improve the end-user QoE for FDSP-streamed videos. Title: Optimization of Flexible Dual-TCP/UDP Streaming Protocol For HD Video Streaming over 802.11 Wireless Networks Author: Dhamodaran, Arul N. Flexible Dual-TCP/UDP Streaming Protocol with Adaptive Bitstream Prioritization (FDSP with Adaptive-BP) is a new method for streaming H.264-encoded High-definition (HD) video over WLANs. Traditionally, video streaming is done either using Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) protocol, resulting in either rebuffering or packet loss respectively. While FDSP-based streaming addresses these issues, it experiences a new set of problems as it incurs both packet loss and re- buffering. This makes the actual Quality of Experience (QoE) delivered to end-users one of the key criteria in the Adaptive-BP selection process. As such, this paper presents an analysis of the subjective impact of both packet loss and rebuffering on video streaming quality as perceived by the end-user. Our QoE study focuses on identifying the threshold limits of both packet loss and rebuffering for the different Mean Opinion Score (MOS) ranges, which can then be applied to the Adaptive-BP algorithm to improve the end-user QoE for FDSP-streamed videos. Close

• 58. [Article] Video streaming in unstructured peer-to-peer networks

  Graduation date: 2009

  Citation × Citation Citation Abstract Copy Title: Video streaming in unstructured peer-to-peer networks Author: Furtado, Craig Graduation date: 2009 Title: Video streaming in unstructured peer-to-peer networks Author: Furtado, Craig Graduation date: 2009 Close

• 59. [Article] Insect community composition and physico-chemical processes in summer-dry streams of Western Oregon

  Seven streams, one of them permanent, were studied in western Oregon, USA. The research was designed to assess the value of summer-dry headwaters for conservation oriented landscape management. Streams ...

  Citation × Citation Citation Abstract Copy Title: Insect community composition and physico-chemical processes in summer-dry streams of Western Oregon Author: Dieterich, Martin Seven streams, one of them permanent, were studied in western Oregon, USA. The research was designed to assess the value of summer-dry headwaters for conservation oriented landscape management. Streams were categorized primarily according to exposure (forest versus meadow sites) and secondarily according to flow duration (ephemeral = short-flow versus temporary = long-flow sites). Ephemeral streams have discontinuous flow and last less than three months annually. Temporary streams have continuous flow for more than five months each season. Ephemeral forest streams were highly efficient at filtering road-generated sediment. Uptake lengths for suspended sediment were short (36 m-105 m) at moderately elevated input concentrations. As a result of the filtration mechanism, filtration efficiency is expected to increase as annual flow duration decreases. Injection experiments yielded nitrate uptake rates of almost 1% per m of temporary stream channel. Exchange with subsurface flow was the most important route for nitrate removal from the water column. Biological uptake was insignificant in a light-limited forest stream, whereas a considerable amount of nitrate was retained by the biota a nutrient-limited meadow channel. At least 207 insect species were collected from the summer-dry streams. Species richness recorded from temporary forest streams exceeded that in an adjacent permanent headwater and there was high overlap between the fauna of the permanent and the temporary streams. Species richness in ephemeral channels was only 1/4 to 1/3 of that in long-flow forest streams. Multivariate analysis of community structure revealed flow duration and microhabitat pattern (riffle-pool) as the most important environmental factors determining faunal composition in temporary forest streams. Summer drought conditions at the sample sites also were important. By providing habitat and contributing to water quality in permanent downstream reaches, summer-dry streams have the potential to serve multiple purposes in conservation management. Their value from a conservation perspective is unexpectedly high. Landscape management therefore should be directed toward the preservation and protection of ephemeral and temporary streams. Title: Insect community composition and physico-chemical processes in summer-dry streams of Western Oregon Author: Dieterich, Martin Seven streams, one of them permanent, were studied in western Oregon, USA. The research was designed to assess the value of summer-dry headwaters for conservation oriented landscape management. Streams were categorized primarily according to exposure (forest versus meadow sites) and secondarily according to flow duration (ephemeral = short-flow versus temporary = long-flow sites). Ephemeral streams have discontinuous flow and last less than three months annually. Temporary streams have continuous flow for more than five months each season. Ephemeral forest streams were highly efficient at filtering road-generated sediment. Uptake lengths for suspended sediment were short (36 m-105 m) at moderately elevated input concentrations. As a result of the filtration mechanism, filtration efficiency is expected to increase as annual flow duration decreases. Injection experiments yielded nitrate uptake rates of almost 1% per m of temporary stream channel. Exchange with subsurface flow was the most important route for nitrate removal from the water column. Biological uptake was insignificant in a light-limited forest stream, whereas a considerable amount of nitrate was retained by the biota a nutrient-limited meadow channel. At least 207 insect species were collected from the summer-dry streams. Species richness recorded from temporary forest streams exceeded that in an adjacent permanent headwater and there was high overlap between the fauna of the permanent and the temporary streams. Species richness in ephemeral channels was only 1/4 to 1/3 of that in long-flow forest streams. Multivariate analysis of community structure revealed flow duration and microhabitat pattern (riffle-pool) as the most important environmental factors determining faunal composition in temporary forest streams. Summer drought conditions at the sample sites also were important. By providing habitat and contributing to water quality in permanent downstream reaches, summer-dry streams have the potential to serve multiple purposes in conservation management. Their value from a conservation perspective is unexpectedly high. Landscape management therefore should be directed toward the preservation and protection of ephemeral and temporary streams. Close

• 60. [Article] Integrating solute transport, metabolism and processing in stream ecosystems

  After three decades of active research coupling hydrology and stream ecology, the connection among solute transport, metabolism and processing is still unresolved. These knowledge gaps obscure the functioning ...

  Citation × Citation Citation Abstract Copy Title: Integrating solute transport, metabolism and processing in stream ecosystems Author: González Pinzón, Ricardo A. After three decades of active research coupling hydrology and stream ecology, the connection among solute transport, metabolism and processing is still unresolved. These knowledge gaps obscure the functioning of stream ecosystems and how those ecosystems interact with other landscape processes. We must resolve these challenges to wisely manage water resources, because there is a need to understand controls on stream ecosystems at local, regional and continental scales, and because we need to predict in-stream biogeochemical processes in environments and conditions that do not have supporting data. More robust methods are required to deconvolve signal imprints of solute transport, metabolism and processing, thus allowing the development and implementation of improved decision-making approaches for stream management. Recognizing that uncertainty and equifinality are ubiquitous issues in hydrologic problems, this dissertation focuses on the development of parsimonious methods to couple solute transport, metabolism and processing in stream ecosystems. These methods consist of scaling and predicting relationships for solute transport, efficient modeling frameworks to estimate processing rates in streams, and the use of the smart tracer resazurin to estimate stream metabolism at different spatial scales. This dissertation is the result of lab and field experiments, meta-analyses, and mathematical, statistical and computational modeling. The most significant contributions of this dissertation to the hydrological and biogeosciences are: (1) there are scaling relationships in stream solute transport. We found that the coefficient of skewness (CSK) of conservative tracer breakthrough curves is statistically constant over time and this result can be used to predict solute transport. (2) The CSK of all commonly used solute transport models decreases over time. This shows that current theory is inconsistent with experimental data and suggests that a revised theory of solute transport is needed. (3) Simple algebraic relationships can be used to estimate processing rates in streams. This eliminates the need to calibrate highly uncertain (and intermediate) parameters. (4) Under some common stream transport conditions dispersion does not play an important role in the estimation of processing rates and, therefore, can be neglected. Under such conditions, no computer modeling is needed to estimate processing rates. (5) Even if the reactions of target and proxy tracers happen in exactly the same locations at rates that are linearly proportional, the exact relationship between the two volume-averaged rates can be nonlinear and a function of transport conditions. However, the uncertainty in the estimation of the target processing rate is linearly proportional to the proxy-tracer processing rate. (6) The transformation of resazurin is nearly perfectly, positively correlated with aerobic microbial respiration. Therefore, resazurin can be used as a surrogate to measure respiration in situ and in vivo at different spatial scales (this is an extension of (5)). (7) Community respiration rates in streams may not need to be "corrected" for temperature between daytime and nighttime, because even when photosynthetically active radiation and stream water temperature are different, respiration rates might not be different across nighttime and daytime conditions. Title: Integrating solute transport, metabolism and processing in stream ecosystems Author: González Pinzón, Ricardo A. After three decades of active research coupling hydrology and stream ecology, the connection among solute transport, metabolism and processing is still unresolved. These knowledge gaps obscure the functioning of stream ecosystems and how those ecosystems interact with other landscape processes. We must resolve these challenges to wisely manage water resources, because there is a need to understand controls on stream ecosystems at local, regional and continental scales, and because we need to predict in-stream biogeochemical processes in environments and conditions that do not have supporting data. More robust methods are required to deconvolve signal imprints of solute transport, metabolism and processing, thus allowing the development and implementation of improved decision-making approaches for stream management. Recognizing that uncertainty and equifinality are ubiquitous issues in hydrologic problems, this dissertation focuses on the development of parsimonious methods to couple solute transport, metabolism and processing in stream ecosystems. These methods consist of scaling and predicting relationships for solute transport, efficient modeling frameworks to estimate processing rates in streams, and the use of the smart tracer resazurin to estimate stream metabolism at different spatial scales. This dissertation is the result of lab and field experiments, meta-analyses, and mathematical, statistical and computational modeling. The most significant contributions of this dissertation to the hydrological and biogeosciences are: (1) there are scaling relationships in stream solute transport. We found that the coefficient of skewness (CSK) of conservative tracer breakthrough curves is statistically constant over time and this result can be used to predict solute transport. (2) The CSK of all commonly used solute transport models decreases over time. This shows that current theory is inconsistent with experimental data and suggests that a revised theory of solute transport is needed. (3) Simple algebraic relationships can be used to estimate processing rates in streams. This eliminates the need to calibrate highly uncertain (and intermediate) parameters. (4) Under some common stream transport conditions dispersion does not play an important role in the estimation of processing rates and, therefore, can be neglected. Under such conditions, no computer modeling is needed to estimate processing rates. (5) Even if the reactions of target and proxy tracers happen in exactly the same locations at rates that are linearly proportional, the exact relationship between the two volume-averaged rates can be nonlinear and a function of transport conditions. However, the uncertainty in the estimation of the target processing rate is linearly proportional to the proxy-tracer processing rate. (6) The transformation of resazurin is nearly perfectly, positively correlated with aerobic microbial respiration. Therefore, resazurin can be used as a surrogate to measure respiration in situ and in vivo at different spatial scales (this is an extension of (5)). (7) Community respiration rates in streams may not need to be "corrected" for temperature between daytime and nighttime, because even when photosynthetically active radiation and stream water temperature are different, respiration rates might not be different across nighttime and daytime conditions. Close