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• 41. [Article] The influence of climate change and restoration on stream temperature

  Water temperature is an essential property of a stream. Temperature regulates physical and biochemical processes in aquatic habitats. Various factors related to climatic conditions, landscape characteristics, ...

  Citation × Citation Citation Abstract Copy Title: The influence of climate change and restoration on stream temperature Author: Diabat, Mousa Water temperature is an essential property of a stream. Temperature regulates physical and biochemical processes in aquatic habitats. Various factors related to climatic conditions, landscape characteristics, and channel structure directly influence stream temperature. Numerous studies indicate that increased average air temperature during the past century has led to stream warming across the world. The trend of stream warming was also present in spring-fed watersheds, where summer flow has decreased. In addition, anthropogenic practices that alter the natural landscape and channel structure, such as forest management, agriculture, and mining contributed to stream warming. For example, deforested and unshaded stream reaches or dredged channels were warmer than shaded reaches and meandering streams. Stream temperatures in North American lotic habitats are of a specific concern due to their significant economic, cultural, and ecological value. With climate projections indicating that air temperature will only continue to rise throughout the 21st century, cold- or cool-water organisms, especially fishes, will be affected. Therefore, there is a strong need to better understand the impacts of changing climate, riparian landscape, and channel structure on a stream's heat budget. This may assist in restoring the historic thermal regime in impacted sites and mitigating the impacts of future climate change. This study looks into the relative influences of the different factors on a stream's heat budget with three manuscripts: one on stream temperature response to diel timing of air warming, one on stream temperature response to changes in air temperature, flow, and riparian vegetation, and one on stream temperature response to air warming and channel reconstruction. I used the software Heat Source version 8.05 to simulate stream temperature for all three analyses along the Middle Fork John Day River, Oregon USA. Two of the manuscripts were applied to an upper 37 km section of the Middle Fork John Day River (presented in chapter 2 and 3), where the third manuscript was applied to a 1.5-km section. The sensitivity analysis of stream temperature response to diel timing of air warming (Chapter 2: Diel Timing of Warmer Air under Climate Change Affects Magnitude, Timing, and Duration of Stream Temperature Change) was based on scenarios representing uniform air warming over the diel period, daytime warming, and nighttime warming. Uniform warming of air temperature is a simple representation of increases in the average daily or monthly temperatures generated by the 'delta method'. The delta method relies on adding a constant value to the air temperature time-series data. This constant value is the difference (delta) between base case average air temperatures and the projected one. Scenarios of daytime or nighttime warming represent conditions under which most of the warming of the air occurs during the daytime or the nighttime, respectively. I simulated the stream temperature response to warmer air conditions of +2 °C and +4 °C in daily average for all three cases of air warming conditions. The three cases of different diel distributions of air warming generated 7-day average daily maximum stream temperature (7DADM) increases of approximately +1.8 °C ± 0.1 °C at the downstream end of the study section relative to the base case. In most parts of the reach, the three distributions of air warming generated different ranges of stream temperatures, different 7DADM values, different durations of stream temperature changes, and different average daily temperatures. Changes of stream temperature were out of phase with imposed changes of air temperature. Therefore, nighttime warming of air temperatures would cause the greatest increase in maximum daily stream temperature, which typically occurs during the daytime. The sensitivity analysis of the relative influences of changes in air temperature, stream flow, and riparian vegetation on stream temperature (Chapter 3: Assessing Stream Temperature Response to Cumulative Influence of Changing Air Temperature, Flow, and Riparian Vegetation). This study summarized stream temperature simulation in 36 scenarios representing possible manifestations of 21st century climate conditions and land management strategies. In addition to existing conditions (base case) of flow, air temperature, and riparian vegetation, scenarios consisted of: two air temperature increases of 2 °C and 4 °C, two stream flow variations of +30% and -30%, three spatially uniform riparian vegetation conditions that create averages of effective shade 7%, 34%, and 79%, in addition to 14% for base case conditions. Results suggest that variation in riparian vegetation was the dominant factor influencing stream temperature because it regulates incoming shortwave radiation, the largest heat input to the stream, while variation in stream flow has a negligible influence. Results indicated that increasing the effective shade along the study section, particularly in the currently unshaded sections, could mitigate the influence of increasing air temperature, and would reduce stream temperature maxima below current values even under future climate conditions of warmer air. With the small influence it had, increasing stream flow reduced the 7DADM under low shade conditions. However, increasing stream flow showed counterintuitive results as it contributed to increasing stream temperature maxima when the stream was heavily shaded. The applied study examined the stream temperature response to restoration practices and their potential to mitigate the influence of warmer air conditions (Chapter 4: Estimating Stream Temperature Response to Restoring Channel and Riparian Vegetation and the Potential to Mitigate Warmer Air Conditions). This study focused on a 1.5 km section along the upper part of the Middle Fork John Day River that was modified due to past anthropogenic activities of mining for gold and timber harvest. Currently, the riparian vegetation of the study site is mostly shrubs and stands of short trees. Restoration designs call for the restoration of both the channel structure and replanting the riparian vegetation. Simulation results showed that the 7DADM was higher in the restored channel than the existing channel with both conditions of low and high effective shade conditions. However, a combined restoration practice of channel reconstruction and medium effective shade conditions reduced stream temperature maxima more than restoring riparian vegetation alone. In addition, results showed that restoring riparian vegetation was sufficient to mitigate the influence of warmer air on stream temperature, while restoring the channel alone is not. Heat budget analysis showed that heat accumulation during the daytime increased in the restored channel, which was longer, narrower, and deeper than the existing channel. It is important to emphasize that stream temperature is one of many goals that restoration activities aim to improve. Furthermore, differences in 7DADM among the different scenarios of restoration are negligible. Such small differences could hardly be measure. While this study examined a short section of 1.5 km, longer stream sections may increase the differences in 7DADM. Primary conclusions of this study are: 1) daily maxima of stream temperature will increase in response to increased air temperature regardless of the distribution of air warming during the diel cycle; 2) nighttime air warming caused a greater increase in stream temperature maximum than daytime warming; 3) riparian vegetation was the dominant factor on stream's heat budget, more than air temperature or stream flow; 4) restoring riparian vegetation mitigated the influence of warmer air; 5) restoring channel structure alone was not sufficient to lower temperature maxima; and 6) restoration project was most successful in improving degraded stream temperature when combined with channel reconstruction and improved riparian shade. Title: The influence of climate change and restoration on stream temperature Author: Diabat, Mousa Water temperature is an essential property of a stream. Temperature regulates physical and biochemical processes in aquatic habitats. Various factors related to climatic conditions, landscape characteristics, and channel structure directly influence stream temperature. Numerous studies indicate that increased average air temperature during the past century has led to stream warming across the world. The trend of stream warming was also present in spring-fed watersheds, where summer flow has decreased. In addition, anthropogenic practices that alter the natural landscape and channel structure, such as forest management, agriculture, and mining contributed to stream warming. For example, deforested and unshaded stream reaches or dredged channels were warmer than shaded reaches and meandering streams. Stream temperatures in North American lotic habitats are of a specific concern due to their significant economic, cultural, and ecological value. With climate projections indicating that air temperature will only continue to rise throughout the 21st century, cold- or cool-water organisms, especially fishes, will be affected. Therefore, there is a strong need to better understand the impacts of changing climate, riparian landscape, and channel structure on a stream's heat budget. This may assist in restoring the historic thermal regime in impacted sites and mitigating the impacts of future climate change. This study looks into the relative influences of the different factors on a stream's heat budget with three manuscripts: one on stream temperature response to diel timing of air warming, one on stream temperature response to changes in air temperature, flow, and riparian vegetation, and one on stream temperature response to air warming and channel reconstruction. I used the software Heat Source version 8.05 to simulate stream temperature for all three analyses along the Middle Fork John Day River, Oregon USA. Two of the manuscripts were applied to an upper 37 km section of the Middle Fork John Day River (presented in chapter 2 and 3), where the third manuscript was applied to a 1.5-km section. The sensitivity analysis of stream temperature response to diel timing of air warming (Chapter 2: Diel Timing of Warmer Air under Climate Change Affects Magnitude, Timing, and Duration of Stream Temperature Change) was based on scenarios representing uniform air warming over the diel period, daytime warming, and nighttime warming. Uniform warming of air temperature is a simple representation of increases in the average daily or monthly temperatures generated by the 'delta method'. The delta method relies on adding a constant value to the air temperature time-series data. This constant value is the difference (delta) between base case average air temperatures and the projected one. Scenarios of daytime or nighttime warming represent conditions under which most of the warming of the air occurs during the daytime or the nighttime, respectively. I simulated the stream temperature response to warmer air conditions of +2 °C and +4 °C in daily average for all three cases of air warming conditions. The three cases of different diel distributions of air warming generated 7-day average daily maximum stream temperature (7DADM) increases of approximately +1.8 °C ± 0.1 °C at the downstream end of the study section relative to the base case. In most parts of the reach, the three distributions of air warming generated different ranges of stream temperatures, different 7DADM values, different durations of stream temperature changes, and different average daily temperatures. Changes of stream temperature were out of phase with imposed changes of air temperature. Therefore, nighttime warming of air temperatures would cause the greatest increase in maximum daily stream temperature, which typically occurs during the daytime. The sensitivity analysis of the relative influences of changes in air temperature, stream flow, and riparian vegetation on stream temperature (Chapter 3: Assessing Stream Temperature Response to Cumulative Influence of Changing Air Temperature, Flow, and Riparian Vegetation). This study summarized stream temperature simulation in 36 scenarios representing possible manifestations of 21st century climate conditions and land management strategies. In addition to existing conditions (base case) of flow, air temperature, and riparian vegetation, scenarios consisted of: two air temperature increases of 2 °C and 4 °C, two stream flow variations of +30% and -30%, three spatially uniform riparian vegetation conditions that create averages of effective shade 7%, 34%, and 79%, in addition to 14% for base case conditions. Results suggest that variation in riparian vegetation was the dominant factor influencing stream temperature because it regulates incoming shortwave radiation, the largest heat input to the stream, while variation in stream flow has a negligible influence. Results indicated that increasing the effective shade along the study section, particularly in the currently unshaded sections, could mitigate the influence of increasing air temperature, and would reduce stream temperature maxima below current values even under future climate conditions of warmer air. With the small influence it had, increasing stream flow reduced the 7DADM under low shade conditions. However, increasing stream flow showed counterintuitive results as it contributed to increasing stream temperature maxima when the stream was heavily shaded. The applied study examined the stream temperature response to restoration practices and their potential to mitigate the influence of warmer air conditions (Chapter 4: Estimating Stream Temperature Response to Restoring Channel and Riparian Vegetation and the Potential to Mitigate Warmer Air Conditions). This study focused on a 1.5 km section along the upper part of the Middle Fork John Day River that was modified due to past anthropogenic activities of mining for gold and timber harvest. Currently, the riparian vegetation of the study site is mostly shrubs and stands of short trees. Restoration designs call for the restoration of both the channel structure and replanting the riparian vegetation. Simulation results showed that the 7DADM was higher in the restored channel than the existing channel with both conditions of low and high effective shade conditions. However, a combined restoration practice of channel reconstruction and medium effective shade conditions reduced stream temperature maxima more than restoring riparian vegetation alone. In addition, results showed that restoring riparian vegetation was sufficient to mitigate the influence of warmer air on stream temperature, while restoring the channel alone is not. Heat budget analysis showed that heat accumulation during the daytime increased in the restored channel, which was longer, narrower, and deeper than the existing channel. It is important to emphasize that stream temperature is one of many goals that restoration activities aim to improve. Furthermore, differences in 7DADM among the different scenarios of restoration are negligible. Such small differences could hardly be measure. While this study examined a short section of 1.5 km, longer stream sections may increase the differences in 7DADM. Primary conclusions of this study are: 1) daily maxima of stream temperature will increase in response to increased air temperature regardless of the distribution of air warming during the diel cycle; 2) nighttime air warming caused a greater increase in stream temperature maximum than daytime warming; 3) riparian vegetation was the dominant factor on stream's heat budget, more than air temperature or stream flow; 4) restoring riparian vegetation mitigated the influence of warmer air; 5) restoring channel structure alone was not sufficient to lower temperature maxima; and 6) restoration project was most successful in improving degraded stream temperature when combined with channel reconstruction and improved riparian shade. Close

• 42. [Article] Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon

  I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande ...

  Citation × Citation Citation Abstract Copy Title: Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon Author: Price, David M. I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units, and microhabitats, and to assess chinook salmon fidelity to those habitats using radio-telemetry. The analyses showed that habitat quality and availability in the seven study streams varied. Each stream posed different physical constraints on adult chinook salmon habitat; this was reflected by the differential use of habitat by salmon among streams. Salmon elected pools almost exclusively in the John Day Basin, whereas pools and riffles were elected in near equal proportion in the Grande Ronde and Inmaha basins. Within streams, use was similar between years. Almost all salmon were observed in association with cover, but the type of cover largely reflected availablity. Chinook salmon elected the deepest depths within channel units (microhabitat scale), but not necessarily the deepest channel units among streams (channel unit scale). Chinook salmon did not elect cooler stream temperatures within channel units in any study stream, except the Middle Fork John Day River. Radio-tagged chinook showed a high fidelity to habitats, except when stream temperatures approached lethal limits. Due to stream specific differences in habitat availability and use, multiscale habitat assessments for individual streams are recommended to increase the success of watershed restoration activities. Title: Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon Author: Price, David M. I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units, and microhabitats, and to assess chinook salmon fidelity to those habitats using radio-telemetry. The analyses showed that habitat quality and availability in the seven study streams varied. Each stream posed different physical constraints on adult chinook salmon habitat; this was reflected by the differential use of habitat by salmon among streams. Salmon elected pools almost exclusively in the John Day Basin, whereas pools and riffles were elected in near equal proportion in the Grande Ronde and Inmaha basins. Within streams, use was similar between years. Almost all salmon were observed in association with cover, but the type of cover largely reflected availablity. Chinook salmon elected the deepest depths within channel units (microhabitat scale), but not necessarily the deepest channel units among streams (channel unit scale). Chinook salmon did not elect cooler stream temperatures within channel units in any study stream, except the Middle Fork John Day River. Radio-tagged chinook showed a high fidelity to habitats, except when stream temperatures approached lethal limits. Due to stream specific differences in habitat availability and use, multiscale habitat assessments for individual streams are recommended to increase the success of watershed restoration activities. Close

• 43. [Image] Big Redfish Lake Stream, Idaho

  	Citation × Citation Citation Abstract Copy Title: Big Redfish Lake Stream, Idaho Year: 1935 Title: Big Redfish Lake Stream, Idaho Year: 1935 Close

• 44. [Image] Big Redfish Lake Stream, Idaho

  	Citation × Citation Citation Abstract Copy Title: Big Redfish Lake Stream, Idaho Year: 1935 Title: Big Redfish Lake Stream, Idaho Year: 1935 Close

• 45. [Image] Boulders in stream

  	Citation × Citation Citation Abstract Copy Title: Boulders in stream Year: 1937 Title: Boulders in stream Year: 1937 Close

• 46. [Article] Oregon State Game Commission, Lakes and Streams, Index of Lakes

  Abstract -- A partial list of lakes and streams of Oregon by county. Also contains lake surveys from the early 1930's. Describes lake and streams general shape, fish species, and location.

  Citation × Citation Citation Abstract Copy Title: Oregon State Game Commission, Lakes and Streams, Index of Lakes Abstract -- A partial list of lakes and streams of Oregon by county. Also contains lake surveys from the early 1930's. Describes lake and streams general shape, fish species, and location. Title: Oregon State Game Commission, Lakes and Streams, Index of Lakes Abstract -- A partial list of lakes and streams of Oregon by county. Also contains lake surveys from the early 1930's. Describes lake and streams general shape, fish species, and location. Close

• 47. [Article] Dynamics of intermediate-size stream outlets, northern Oregon coast

  This study measured and evaluated the relation of coastal foredune morphology to stream beach outlets, and investigated the processes associated with the stream outlet. Intermediate-size streams were studied, ...

  Citation × Citation Citation Abstract Copy Title: Dynamics of intermediate-size stream outlets, northern Oregon coast Author: Eberhardt, Ellen Year: 1988 This study measured and evaluated the relation of coastal foredune morphology to stream beach outlets, and investigated the processes associated with the stream outlet. Intermediate-size streams were studied, and defined as those that flow across the beach most of the year but have no tidal influence. Fifty-four of these streams were found along the northern Oregon coast between the Columbia River and Yaquina Bay. Crescent Lake Outlet, Saltair Creek and Daley Lake Outlet were chosen as study streams for further investigation. Title: Dynamics of intermediate-size stream outlets, northern Oregon coast Author: Eberhardt, Ellen Year: 1988 This study measured and evaluated the relation of coastal foredune morphology to stream beach outlets, and investigated the processes associated with the stream outlet. Intermediate-size streams were studied, and defined as those that flow across the beach most of the year but have no tidal influence. Fifty-four of these streams were found along the northern Oregon coast between the Columbia River and Yaquina Bay. Crescent Lake Outlet, Saltair Creek and Daley Lake Outlet were chosen as study streams for further investigation. Close

• 48. [Article] Summer low flow characteristics of forest streams in northeast Oregon

  Summer low flow characteristics of six forest streams in Northeast Oregon were examined using long term streamflow records. Time series and trend analysis revealed highly significant (alpha=O.O1) increasing ...

  Citation × Citation Citation Abstract Copy Title: Summer low flow characteristics of forest streams in northeast Oregon Author: Widner, Gregory L. Summer low flow characteristics of six forest streams in Northeast Oregon were examined using long term streamflow records. Time series and trend analysis revealed highly significant (alpha=O.O1) increasing trends in summer low flow over the period of record on four of the selected streams, and significant (alpha=O.05) year-to-year dependence on three of the selected streams. Low flow frequency curves, flow duration curves, and flow-date curves were constructed for each stream from the long term flow records. A simple method of forecasting streamflow recessions using flow records is developed resulting in improvement over the average in forecasting recession volume, but little improvement in forecasting end-of-water year flow levels. Title: Summer low flow characteristics of forest streams in northeast Oregon Author: Widner, Gregory L. Summer low flow characteristics of six forest streams in Northeast Oregon were examined using long term streamflow records. Time series and trend analysis revealed highly significant (alpha=O.O1) increasing trends in summer low flow over the period of record on four of the selected streams, and significant (alpha=O.05) year-to-year dependence on three of the selected streams. Low flow frequency curves, flow duration curves, and flow-date curves were constructed for each stream from the long term flow records. A simple method of forecasting streamflow recessions using flow records is developed resulting in improvement over the average in forecasting recession volume, but little improvement in forecasting end-of-water year flow levels. Close

• 49. [Article] Enchanted Valley stream restoration and meadow management project decision notice and finding of no significant impact

  27 pp. Illus. T. 17 S., R. 11 W., Sections 19 & 30. Captured February 28, 2008.

  Citation × Citation Citation Abstract Copy Title: Enchanted Valley stream restoration and meadow management project decision notice and finding of no significant impact Author: Mapleton Ranger District (Or.) Year: 2008, 2007 27 pp. Illus. T. 17 S., R. 11 W., Sections 19 & 30. Captured February 28, 2008. Title: Enchanted Valley stream restoration and meadow management project decision notice and finding of no significant impact Author: Mapleton Ranger District (Or.) Year: 2008, 2007 27 pp. Illus. T. 17 S., R. 11 W., Sections 19 & 30. Captured February 28, 2008. Close

• 50. [Article] Oregon Hydrography - Whole Stream Routes

  Abstract -- This dataset provides a representation of the watercourses within the Oregon portion of the Columbia basin as well as coastal and Great Basin watersheds. A selected subset of streams were originally ...

  Citation × Citation Citation Abstract Copy Title: Oregon Hydrography - Whole Stream Routes Abstract -- This dataset provides a representation of the watercourses within the Oregon portion of the Columbia basin as well as coastal and Great Basin watersheds. A selected subset of streams were originally derived from the Framework hydrography dataset and include all records originally present within the 1:100,000 scale PNW Hydrography dataset, named 1:24,000 scale streams and unnamed 1:24,000 scale streams where ODFW managed aquatic resource information exist. The data were migrated to events on NHD between 2012 and 2014. Additional features were added in 2017 and all events were synchronized to April 2017 NHD. Title: Oregon Hydrography - Whole Stream Routes Abstract -- This dataset provides a representation of the watercourses within the Oregon portion of the Columbia basin as well as coastal and Great Basin watersheds. A selected subset of streams were originally derived from the Framework hydrography dataset and include all records originally present within the 1:100,000 scale PNW Hydrography dataset, named 1:24,000 scale streams and unnamed 1:24,000 scale streams where ODFW managed aquatic resource information exist. The data were migrated to events on NHD between 2012 and 2014. Additional features were added in 2017 and all events were synchronized to April 2017 NHD. Close