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• 1. [Article] The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon

  Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream ...

  Citation × Citation Citation Abstract Copy Title: The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon Author: Kibler, Kelly Maren Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream can increase the amount of solar radiation the stream receives, which can elevate stream temperatures and impair aquatic habitat. Oregon Forest Practice Rules mandate that forest operators leave Riparian Management Areas (RMAs) adjacent to streams in order to minimize the water quality impacts from forest harvesting. However, RMAs that contain overstory merchantable conifers are not required for small non-fish-bearing streams in Oregon, thus there is potential for increases in stream temperature to occur in headwater streams after harvesting. There is concern that increases in stream temperatures and changes to onsite processes in non-fish-bearing, headwater streams may propagate downstream and impair habitat in fish-bearing streams. The objectives of the following work are to assess the effects of contemporary forest management practices on stream temperatures of small non-fish-bearing headwater streams and to develop new knowledge regarding the physical processes that control reach-level stream temperature patterns. Summer stream temperatures were measured for five years in six headwater streams in the Hinkle Creek basin in southern Oregon. After four years, four of the streams were harvested and vegetated RMAs were not left between the streams and harvest units. The watersheds of the two remaining streams were not disturbed. Post-harvest stream temperatures were monitored for one year in all six streams. Each harvested stream was paired with one unharvested stream and regression relationships for maximum, minimum and mean daily stream temperatures were developed. Changes to temperatures of harvested streams were detected by comparing the mean pre-harvest regression relationship to the mean post-harvest relationship. Change detection analyses that considered the mean response among all four harvested streams indicated that maximum daily stream temperatures did not increase after harvesting, but that minimum and mean daily temperatures decreased significantly after harvesting. Additionally, diel stream temperature fluctuations were significantly greater one year after harvesting. Pre- and post-harvest surveys of canopy closure in the harvested and unharvested streams were completed in order to compare levels of stream shading before and after harvest. The post-harvest survey quantified canopy closure from remaining overstory vegetation as well as from logging slash that partially covered the harvested streams. The surveys indicated that mean overstory canopy closure in the harvested streams decreased by 84% as a result of the harvest, but as the logging slash provided considerable cover, total canopy closure decreased by only 20%. It is possible that the logging slash effectively attenuated solar radiation and prevented extreme temperature increases in the harvested streams. However, it is likely that streamflow increased after harvesting and that the increased streamflow also prevented increases to maximum temperatures and contributed to lower minimum and mean stream temperatures. Title: The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon Author: Kibler, Kelly Maren Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream can increase the amount of solar radiation the stream receives, which can elevate stream temperatures and impair aquatic habitat. Oregon Forest Practice Rules mandate that forest operators leave Riparian Management Areas (RMAs) adjacent to streams in order to minimize the water quality impacts from forest harvesting. However, RMAs that contain overstory merchantable conifers are not required for small non-fish-bearing streams in Oregon, thus there is potential for increases in stream temperature to occur in headwater streams after harvesting. There is concern that increases in stream temperatures and changes to onsite processes in non-fish-bearing, headwater streams may propagate downstream and impair habitat in fish-bearing streams. The objectives of the following work are to assess the effects of contemporary forest management practices on stream temperatures of small non-fish-bearing headwater streams and to develop new knowledge regarding the physical processes that control reach-level stream temperature patterns. Summer stream temperatures were measured for five years in six headwater streams in the Hinkle Creek basin in southern Oregon. After four years, four of the streams were harvested and vegetated RMAs were not left between the streams and harvest units. The watersheds of the two remaining streams were not disturbed. Post-harvest stream temperatures were monitored for one year in all six streams. Each harvested stream was paired with one unharvested stream and regression relationships for maximum, minimum and mean daily stream temperatures were developed. Changes to temperatures of harvested streams were detected by comparing the mean pre-harvest regression relationship to the mean post-harvest relationship. Change detection analyses that considered the mean response among all four harvested streams indicated that maximum daily stream temperatures did not increase after harvesting, but that minimum and mean daily temperatures decreased significantly after harvesting. Additionally, diel stream temperature fluctuations were significantly greater one year after harvesting. Pre- and post-harvest surveys of canopy closure in the harvested and unharvested streams were completed in order to compare levels of stream shading before and after harvest. The post-harvest survey quantified canopy closure from remaining overstory vegetation as well as from logging slash that partially covered the harvested streams. The surveys indicated that mean overstory canopy closure in the harvested streams decreased by 84% as a result of the harvest, but as the logging slash provided considerable cover, total canopy closure decreased by only 20%. It is possible that the logging slash effectively attenuated solar radiation and prevented extreme temperature increases in the harvested streams. However, it is likely that streamflow increased after harvesting and that the increased streamflow also prevented increases to maximum temperatures and contributed to lower minimum and mean stream temperatures. Close

• 2. [Article] Large woody debris and channel morphology of undisturbed streams in southeast Alaska

  The characteristics and interactions of the riparian stand, large woody debris (LWD), and channel morphology were examined on five undisturbed, low gradient streams in southeast Alaska. One first-, two ...

  Citation × Citation Citation Abstract Copy Title: Large woody debris and channel morphology of undisturbed streams in southeast Alaska Author: Robison, E. George The characteristics and interactions of the riparian stand, large woody debris (LWD), and channel morphology were examined on five undisturbed, low gradient streams in southeast Alaska. One first-, two second-, one third-, and one fourth-order streams were studied. Stream morphology variables were measured systematically at fixed intervals of three to ten feet depending on stream size: 50-foot intervals were used for riparian forest measurements. The percentage of alder comprising the riparian forest increased with stream size. The first- and second-order streams had alder comprising approximately 8% of the total basal area whereas, the fourth-order stream had 25 Likewise, the percentage of LWD pieces consisting of alder increased from 129 in the two smallest first and second-order streams to 319 in the fourth-order stream. These findings, along with inspection of air photos indicate a alternating 1'one sided" alder corridor exists along the largest stream. The proportion of large woody debris pieces with rootwads in the channel increased from 2 and 6% in the two smallest first- and second-order streams to 32° in the fourth-order stream indicating the largest stream has recruited LWD from bank cutting and/or lateral channel migration. LWD oriented perpendicular (900) to general stream flow was relatively frequent for all streams. No significant (alpha=0.05) linear relationship was found (r2<O.05) between piece length and orientation to flow. Channel morphology changed with stream size. For example, the length of stream with side channels and/or braided reaches increased from 1% in the first-order stream to 416 of stream length in the fourth-order stream. The overall percentage of pools averaged 579 and showed no changes with changes in stream size. However, the relative proportions of individual pool "morphological types" and "causal elements" did change with stream size. "Underf low pools" comprised less than 10% of the morphological types in the first-, second-, and third-order streams but increased to 17% in the fourth-order stream. Autocorrelations of the spatial distributions of stream morphological variables (i.e., depth and width) indicated that the streams are influenced by a wide variety of interacting factors and processes. Thus channel dimensions are characterized by high variability and an absence of "memory" or repeatable" components. A positive linear relationship (alpha<O.O1, r2=O.23) was found between LWD volume and the standard deviation of bankfull width. No such relationships were found for other stream morphological variables including thalweg depth, low-flow width, cross-sectional area, and width depth ratio, indicating other variables besides wood volume present are influencing variability in stream morphology, or that the effects of large woody debris upon channel morphology is not easily expressed by linear regression techniques. Autocorrelations and frequency histograms of an upstream forested section, with instream LWD, and a downstream meadow section with no LWD, noncohesive soils and tidal effects, show that the meadow section had greater "memory" and less diversity in "morphological types" and "pool causal elements." These results provide a quantitative assessment of several stream morphology variables for first- through fourth-order streams in southeast Alaska. Further research is needed to compare these results for undisturbed streams with streams influenced by management activities. Title: Large woody debris and channel morphology of undisturbed streams in southeast Alaska Author: Robison, E. George The characteristics and interactions of the riparian stand, large woody debris (LWD), and channel morphology were examined on five undisturbed, low gradient streams in southeast Alaska. One first-, two second-, one third-, and one fourth-order streams were studied. Stream morphology variables were measured systematically at fixed intervals of three to ten feet depending on stream size: 50-foot intervals were used for riparian forest measurements. The percentage of alder comprising the riparian forest increased with stream size. The first- and second-order streams had alder comprising approximately 8% of the total basal area whereas, the fourth-order stream had 25 Likewise, the percentage of LWD pieces consisting of alder increased from 129 in the two smallest first and second-order streams to 319 in the fourth-order stream. These findings, along with inspection of air photos indicate a alternating 1'one sided" alder corridor exists along the largest stream. The proportion of large woody debris pieces with rootwads in the channel increased from 2 and 6% in the two smallest first- and second-order streams to 32° in the fourth-order stream indicating the largest stream has recruited LWD from bank cutting and/or lateral channel migration. LWD oriented perpendicular (900) to general stream flow was relatively frequent for all streams. No significant (alpha=0.05) linear relationship was found (r2<O.05) between piece length and orientation to flow. Channel morphology changed with stream size. For example, the length of stream with side channels and/or braided reaches increased from 1% in the first-order stream to 416 of stream length in the fourth-order stream. The overall percentage of pools averaged 579 and showed no changes with changes in stream size. However, the relative proportions of individual pool "morphological types" and "causal elements" did change with stream size. "Underf low pools" comprised less than 10% of the morphological types in the first-, second-, and third-order streams but increased to 17% in the fourth-order stream. Autocorrelations of the spatial distributions of stream morphological variables (i.e., depth and width) indicated that the streams are influenced by a wide variety of interacting factors and processes. Thus channel dimensions are characterized by high variability and an absence of "memory" or repeatable" components. A positive linear relationship (alpha<O.O1, r2=O.23) was found between LWD volume and the standard deviation of bankfull width. No such relationships were found for other stream morphological variables including thalweg depth, low-flow width, cross-sectional area, and width depth ratio, indicating other variables besides wood volume present are influencing variability in stream morphology, or that the effects of large woody debris upon channel morphology is not easily expressed by linear regression techniques. Autocorrelations and frequency histograms of an upstream forested section, with instream LWD, and a downstream meadow section with no LWD, noncohesive soils and tidal effects, show that the meadow section had greater "memory" and less diversity in "morphological types" and "pool causal elements." These results provide a quantitative assessment of several stream morphology variables for first- through fourth-order streams in southeast Alaska. Further research is needed to compare these results for undisturbed streams with streams influenced by management activities. Close

• 3. [Article] Contributions of riparian vegetation and stream morphology to headwater stream temperature patterns in the Oregon Coast Range

  The role of riparian forests in maintaining temperatures of headwater streams is well established and is a foundation of forest practice rules designed to protect streamwater quality. However, detailed ...

  Citation × Citation Citation Abstract Copy Title: Contributions of riparian vegetation and stream morphology to headwater stream temperature patterns in the Oregon Coast Range Author: Smith, Danielle D. The role of riparian forests in maintaining temperatures of headwater streams is well established and is a foundation of forest practice rules designed to protect streamwater quality. However, detailed investigation is still needed quantifying specific characteristics of stream systems that affect streamwater temperature including riparian features, stream morphology, and subsurface interactions. The objectives of this research were to investigate summertime streamwater temperature patterns and identify characteristics within headwater streams and riparian zones that influence stream temperature. This study was designed to evaluate these relationships prior to logging in 38 perennial headwater catchments of the Oregon Coast Range. Stream reaches of greater than 1000 m were instrumented with temperature probes and selected stream and riparian characteristics were measured at 60-m intervals within each study reach in 2002 and 2003. A subset of the streams was examined in 2003 to determine the potential influence of streamwater residence time on temperature patterns. Findings suggest that canopy cover is the driving factor controlling summer stream temperature in these small headwater streams, but other stream and riparian characteristics should not be discarded. Longitudinal stream temperature patterns were quite variable for these forested streams and results suggest a high degree of complexity in small headwater streams. Maximum 7-day moving average temperatures ranged from 11.4°C to 16.8°C, with three streams above the standard 16°C threshold. Effects of stream and riparian characteristics on stream temperature were strongest when average of the weekly high temperature was assessed, suggesting this may be a more sensitive index of stream temperature than the commonly used maximum 7-day moving average. Results of tracer dilution tests were inconclusive in that temperature was not consistently correlated to residence time in streams. Title: Contributions of riparian vegetation and stream morphology to headwater stream temperature patterns in the Oregon Coast Range Author: Smith, Danielle D. The role of riparian forests in maintaining temperatures of headwater streams is well established and is a foundation of forest practice rules designed to protect streamwater quality. However, detailed investigation is still needed quantifying specific characteristics of stream systems that affect streamwater temperature including riparian features, stream morphology, and subsurface interactions. The objectives of this research were to investigate summertime streamwater temperature patterns and identify characteristics within headwater streams and riparian zones that influence stream temperature. This study was designed to evaluate these relationships prior to logging in 38 perennial headwater catchments of the Oregon Coast Range. Stream reaches of greater than 1000 m were instrumented with temperature probes and selected stream and riparian characteristics were measured at 60-m intervals within each study reach in 2002 and 2003. A subset of the streams was examined in 2003 to determine the potential influence of streamwater residence time on temperature patterns. Findings suggest that canopy cover is the driving factor controlling summer stream temperature in these small headwater streams, but other stream and riparian characteristics should not be discarded. Longitudinal stream temperature patterns were quite variable for these forested streams and results suggest a high degree of complexity in small headwater streams. Maximum 7-day moving average temperatures ranged from 11.4°C to 16.8°C, with three streams above the standard 16°C threshold. Effects of stream and riparian characteristics on stream temperature were strongest when average of the weekly high temperature was assessed, suggesting this may be a more sensitive index of stream temperature than the commonly used maximum 7-day moving average. Results of tracer dilution tests were inconclusive in that temperature was not consistently correlated to residence time in streams. Close

• 4. [Article] Headwater stream macroinvertebrates of the H.J. Andrews Experimental Forest, Oregon

  Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects ...

  Citation × Citation Citation Abstract Copy Title: Headwater stream macroinvertebrates of the H.J. Andrews Experimental Forest, Oregon Author: Frady, Charles H. Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects of forest harvest on macroinvertebrate communities in headwater streams. This study investigated headwater stream macroinvertebrate communities in the H.J. Andrews Experimental Forest, Oregon, U.S.A and used a paired-stream study design to examine the effect of prior forest harvest on stream macroinvertebrates. Concomitantly, this study examined how macroinvertebrate life-history traits were related to stream size, substrates, discharge, or water temperature. Results from this study suggest that neither richness nor densities differed between streams flowing through young growth versus old growth forests. Despite similarities among these metrics, multivariate ordination techniques helped elucidate differences in benthic community composition between paired streams when red alder was present in riparian zones of previously harvested basins. Indicator Species Analysis of community composition and abundance revealed that no taxa were exclusively indicative of either forest type. Macroinvertebrate life-history traits among headwater streams were related to stream size, stream substrates, or stream discharge. As predicted, macroinvertebrates that ingest leaf litter (shredders) decreased proportionally with increasing stream width, while macroinvertebrates that scrape off algae and biofilms from instream substrates (scrapers) increased with increasing stream width. Differences in macroinvertebrate habit-trait groups were related to differences in stream substrates or stream discharge between very small headwater streams (< 20ha basin area) and larger headwater streams (50-100ha basin size). Seasonal variation in stream discharge also influenced macroinvertebrate communities. Patterns in adult insect emergence in these streams displayed pulses of activity that varied among streams. During summer 2003, total emergence was greatest in one high elevation stream in this study. During spring 2004, total emergence began earlier in one low elevation and one mid elevation stream, but linkages with stream water temperature were tenuous; cumulative emergence remained higher in these streams than all others through early summer 2004. Though forest harvest often has immediate effects on macroinvertebrate communities, shifts in community composition may persist long-term if regrowth of riparian vegetation includes red alder (Alnus rubra). Analyses of macroinvertebrate life-history traits provided insight regarding species adaptations to environmental conditions. Among six headwater streams within a relatively small landscape (6400ha), proportions of stream macroinvertebrate communities with specific traits differed among streams relative to variability in physical stream attributes. Title: Headwater stream macroinvertebrates of the H.J. Andrews Experimental Forest, Oregon Author: Frady, Charles H. Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects of forest harvest on macroinvertebrate communities in headwater streams. This study investigated headwater stream macroinvertebrate communities in the H.J. Andrews Experimental Forest, Oregon, U.S.A and used a paired-stream study design to examine the effect of prior forest harvest on stream macroinvertebrates. Concomitantly, this study examined how macroinvertebrate life-history traits were related to stream size, substrates, discharge, or water temperature. Results from this study suggest that neither richness nor densities differed between streams flowing through young growth versus old growth forests. Despite similarities among these metrics, multivariate ordination techniques helped elucidate differences in benthic community composition between paired streams when red alder was present in riparian zones of previously harvested basins. Indicator Species Analysis of community composition and abundance revealed that no taxa were exclusively indicative of either forest type. Macroinvertebrate life-history traits among headwater streams were related to stream size, stream substrates, or stream discharge. As predicted, macroinvertebrates that ingest leaf litter (shredders) decreased proportionally with increasing stream width, while macroinvertebrates that scrape off algae and biofilms from instream substrates (scrapers) increased with increasing stream width. Differences in macroinvertebrate habit-trait groups were related to differences in stream substrates or stream discharge between very small headwater streams (< 20ha basin area) and larger headwater streams (50-100ha basin size). Seasonal variation in stream discharge also influenced macroinvertebrate communities. Patterns in adult insect emergence in these streams displayed pulses of activity that varied among streams. During summer 2003, total emergence was greatest in one high elevation stream in this study. During spring 2004, total emergence began earlier in one low elevation and one mid elevation stream, but linkages with stream water temperature were tenuous; cumulative emergence remained higher in these streams than all others through early summer 2004. Though forest harvest often has immediate effects on macroinvertebrate communities, shifts in community composition may persist long-term if regrowth of riparian vegetation includes red alder (Alnus rubra). Analyses of macroinvertebrate life-history traits provided insight regarding species adaptations to environmental conditions. Among six headwater streams within a relatively small landscape (6400ha), proportions of stream macroinvertebrate communities with specific traits differed among streams relative to variability in physical stream attributes. Close

• 5. [Article] Patterns and Impacts of Urban Stream Burial and the Potential for Stream Daylighting in Portland, Oregon

  Over the last 150 years, many urban areas have seen streams disappear underground into sewer systems and pipes. Stream burial, the rerouting of open channels to pipes and culverts, has a strong positive ...

  Citation × Citation Citation Abstract Copy Title: Patterns and Impacts of Urban Stream Burial and the Potential for Stream Daylighting in Portland, Oregon Author: Weil, Ella Year: 2017 Over the last 150 years, many urban areas have seen streams disappear underground into sewer systems and pipes. Stream burial, the rerouting of open channels to pipes and culverts, has a strong positive correlation with urban development. Patterns of development contributing to stream burial include the building of freeways, roads, sewer infrastructure, and residential housing. This study uses a combination of archival analysis, spatial analysis, and statistical methods to determine the patterns and impacts of stream burial in Portland, Oregon. Urban stream deserts have been identified in many metropolitan areas and can be defined as areas with dense urban development that have lost all hydrological connectivity. This study discusses the history of stream burial in Portland, delineates Portland's urban stream desert and identifies ecological impacts associated with stream burial. Spatial analysis shows the hotspots of stream deserts are concentrated in east Portland where both impervious areas and pipes are highly co-present. Water quality analysis is conducted by comparing five urban subwatersheds with varying degrees of burial and identifying the differences in water quality between upstream open channels and downstream buried reaches. While the ecological impacts of stream burial are not uniform, it can be argued that there is a relationship between stream burial and stream degradation. The results from the available data show significant differences between the upstream and downstream sites in three streams for several water quality parameters, and two streams that showed very little difference between upstream and downstream sites. The streams with the greatest variance in land use across the subwatershed had the most significant changes in water quality between the upstream and downstream sites. This study concludes by looking at stream daylighting as an option for both ecological restoration and social benefits. Recent efforts to design around existing nature and daylight streams in urban environments have contributed to improved water quality, increased biodiversity, community engagement, and reduced strain on aging sewer infrastructure. Title: Patterns and Impacts of Urban Stream Burial and the Potential for Stream Daylighting in Portland, Oregon Author: Weil, Ella Year: 2017 Over the last 150 years, many urban areas have seen streams disappear underground into sewer systems and pipes. Stream burial, the rerouting of open channels to pipes and culverts, has a strong positive correlation with urban development. Patterns of development contributing to stream burial include the building of freeways, roads, sewer infrastructure, and residential housing. This study uses a combination of archival analysis, spatial analysis, and statistical methods to determine the patterns and impacts of stream burial in Portland, Oregon. Urban stream deserts have been identified in many metropolitan areas and can be defined as areas with dense urban development that have lost all hydrological connectivity. This study discusses the history of stream burial in Portland, delineates Portland's urban stream desert and identifies ecological impacts associated with stream burial. Spatial analysis shows the hotspots of stream deserts are concentrated in east Portland where both impervious areas and pipes are highly co-present. Water quality analysis is conducted by comparing five urban subwatersheds with varying degrees of burial and identifying the differences in water quality between upstream open channels and downstream buried reaches. While the ecological impacts of stream burial are not uniform, it can be argued that there is a relationship between stream burial and stream degradation. The results from the available data show significant differences between the upstream and downstream sites in three streams for several water quality parameters, and two streams that showed very little difference between upstream and downstream sites. The streams with the greatest variance in land use across the subwatershed had the most significant changes in water quality between the upstream and downstream sites. This study concludes by looking at stream daylighting as an option for both ecological restoration and social benefits. Recent efforts to design around existing nature and daylight streams in urban environments have contributed to improved water quality, increased biodiversity, community engagement, and reduced strain on aging sewer infrastructure. Close

• 6. [Article] The thermal characteristics of hydrologically intact Type C and E streams in eastern Oregon

  Many streams in eastern Oregon are listed as water quality impaired on the basis of water temperature. However, it is often difficult to predict water temperature for these streams even if there are no ...

  Citation × Citation Citation Abstract Copy Title: The thermal characteristics of hydrologically intact Type C and E streams in eastern Oregon Author: Hopkins, Karl T. Many streams in eastern Oregon are listed as water quality impaired on the basis of water temperature. However, it is often difficult to predict water temperature for these streams even if there are no anthropogenic impacts. We measured air and water temperature and stream characteristics on three Type C and E channel streams to determine if stream type can help predict stream thermal characteristics. All six streams were hydrologically intact, assessed as Proper Functioning Condition (PFC), and were located in eastern and south central Oregon. Water and air temperatures and stream geomorphic data were taken during the summer months of 1998 and 1999. Average daily maximum and minimum water temperature and average daily maximum and minimum rates of change in water temperature following normalization of data with estimated water residence time were analyzed. There was more variation within stream type than across groups, which precluded separation of stream types based on thermal characteristics. Most streams regardless of type and year exhibited similar daily mean nighttime recoveries of approximately 0.53°C/hour cooling in the downstream direction following normalization by water residence time. All of the streams heated at least 1.0°C/hour during the day with some streams gaining 2.25°C/hour in the downstream direction following normalization by water residence time. Thermal variation among the streams was likely a result of the daily initial water temperature, the gradient between stream and thermal environment, and the varied physical character of each stream within type. Atmospheric temperature is probably the single most critical factor for characterizing stream temperature behavior during the periods of heating and cooling. Title: The thermal characteristics of hydrologically intact Type C and E streams in eastern Oregon Author: Hopkins, Karl T. Many streams in eastern Oregon are listed as water quality impaired on the basis of water temperature. However, it is often difficult to predict water temperature for these streams even if there are no anthropogenic impacts. We measured air and water temperature and stream characteristics on three Type C and E channel streams to determine if stream type can help predict stream thermal characteristics. All six streams were hydrologically intact, assessed as Proper Functioning Condition (PFC), and were located in eastern and south central Oregon. Water and air temperatures and stream geomorphic data were taken during the summer months of 1998 and 1999. Average daily maximum and minimum water temperature and average daily maximum and minimum rates of change in water temperature following normalization of data with estimated water residence time were analyzed. There was more variation within stream type than across groups, which precluded separation of stream types based on thermal characteristics. Most streams regardless of type and year exhibited similar daily mean nighttime recoveries of approximately 0.53°C/hour cooling in the downstream direction following normalization by water residence time. All of the streams heated at least 1.0°C/hour during the day with some streams gaining 2.25°C/hour in the downstream direction following normalization by water residence time. Thermal variation among the streams was likely a result of the daily initial water temperature, the gradient between stream and thermal environment, and the varied physical character of each stream within type. Atmospheric temperature is probably the single most critical factor for characterizing stream temperature behavior during the periods of heating and cooling. Close

• 7. [Article] Heat source : stream, river and open channel temperature prediction

  Reach defined analysis concentrated on the water temperature change that occurred in a stream/river segment over the course of one full diurnal cycle. Digital thermistors, data loggers and computer model ...

  Citation × Citation Citation Abstract Copy Title: Heat source : stream, river and open channel temperature prediction Author: Boyd, Matthew S. Reach defined analysis concentrated on the water temperature change that occurred in a stream/river segment over the course of one full diurnal cycle. Digital thermistors, data loggers and computer model development were utilized in reach analysis to link parameters of the stream system to a specific temperature change. The methodology employed was relatively simple and fast, and many successive stream segments were analyzed simultaneously. Reach analysis of stream temperature change identified the existing components of the stream system that caused increased water temperature and predicted the effectiveness of managed improvements to the stream system. Stream and river temperature regulation has focused on system and basin wide management. Often, the source of increased water temperature originates in only a part of the stream system. Reach defined analysis identified the portions of the stream system in which most water temperature change occurred, offered an explanation for the temperature response and provided specific information about the alternate strategies that may ameliorate undesired water temperatures. The development of the computer model Heat Source included physically based mathematical descriptions of stream energy and hydrologic processes. An implicit finite difference numerical method was implemented for simultaneous solution. The methodology presented in Heat Source is portable and applicable to all streams, rivers and open channels. Title: Heat source : stream, river and open channel temperature prediction Author: Boyd, Matthew S. Reach defined analysis concentrated on the water temperature change that occurred in a stream/river segment over the course of one full diurnal cycle. Digital thermistors, data loggers and computer model development were utilized in reach analysis to link parameters of the stream system to a specific temperature change. The methodology employed was relatively simple and fast, and many successive stream segments were analyzed simultaneously. Reach analysis of stream temperature change identified the existing components of the stream system that caused increased water temperature and predicted the effectiveness of managed improvements to the stream system. Stream and river temperature regulation has focused on system and basin wide management. Often, the source of increased water temperature originates in only a part of the stream system. Reach defined analysis identified the portions of the stream system in which most water temperature change occurred, offered an explanation for the temperature response and provided specific information about the alternate strategies that may ameliorate undesired water temperatures. The development of the computer model Heat Source included physically based mathematical descriptions of stream energy and hydrologic processes. An implicit finite difference numerical method was implemented for simultaneous solution. The methodology presented in Heat Source is portable and applicable to all streams, rivers and open channels. Close

• 8. [Article] Processes that influence the downstream propagation of heat in streams below clearcut harvest units : Hinkle Creek paired watershed study

  This research investigates the direct and downstream impacts of clearcut harvest units on stream temperature as a part of the Hinkle Creek Paired Watershed Study. The Hinkle Creek watershed is located ...

  Citation × Citation Citation Abstract Copy Title: Processes that influence the downstream propagation of heat in streams below clearcut harvest units : Hinkle Creek paired watershed study Author: Otis, Timothy Leonard This research investigates the direct and downstream impacts of clearcut harvest units on stream temperature as a part of the Hinkle Creek Paired Watershed Study. The Hinkle Creek watershed is located in the foothills of the Cascade Mountains about 30 kilometers northeast of Roseburg, Oregon, is privately owned, and supports a 60-year old, harvest-regenerated, Douglas-fir forest. The study watershed contains four treatment and two control sub-watersheds within the larger treatment and control watersheds, respectively. The first harvest entry, which took place during the winter 2005–2006, consisted of five clearcut harvest units located adjacent to perennial, non-fish-bearing streams. One year each of calibration and post-harvest data are analyzed. The experimental design for the study was a Before-After-Control-Impact (BACI) design. Maximum daily stream temperatures (MDST) were analyzed for the four treatment streams for one year before and one year after harvest. A multiple linear regression model was used to compare the 2005 data with the 2006 data for each stream. Stream temperature data from Myers Creek (temperature probe C04) was the control. The model for this analysis was: yt = μ +α + βx + ε where yt is the temperature of the stream on a day t, μ is the overall mean value of y, αi is the effect of year, xt is the corresponding temperature of the control stream on a day t, β is the coefficient estimated by regression, and εt is the error term. This method is an analysis of variance of values that are adjusted for regression with an independent variable, in this case the maximum daily temperatures of the control stream. The impact of timber harvest on MDST is small when compared to the spatial (between-stream) variation in MDST and this impact decreased downstream. At 300 meters, nominally, downstream of the harvest units the impact of timber harvest on MDST was not statistically significant for two streams and only moderately statistically significant for the other two streams. Stream velocity, discharge, and groundwater advection in the streams downstream of the harvest units were quantified using dye tracer dilution techniques. The One-dimensional Transport with Inflow and Storage (OTIS) model was used to quantify longitudinal dispersions, transient storage volumes, storage transfer rates, and hyporheic residence times in four 75 meter reaches in each of the four treatment streams. Stream velocities calculated with OTIS ranged from 0.24 to 0.40 m/sec for the four streams. Dispersions ranged from 0.18 and 0.84 m2/sec. The estimated crosssectional area of the ‘immobile’ zones of water storage divided by the stream cross-sectional area, As/A or the storage ratio, varied from near zero to 7.2. The residence times of water in hyporheic storage ranged from 2.3 hrs to 32 hrs. Water stored in a shaded reach of stream, in pools, and in hyporheic zones provides a volume of water that can be exchanged with the water in the active stream channel. This provides for physical mixing with cooler water and heat transfer to the stream bed. Latent heat, Sensible heat, Longwave Radiant heat and Photosynthetically Active Radiation (PAR) were calculated for August 7-17, 2006 at the center of the 300 meter study reach in Russell Creek. The air temperature was lower than stream temperature during four of those nights and the stream cooled due to a net loss of longwave radiation and evaporative cooling. Title: Processes that influence the downstream propagation of heat in streams below clearcut harvest units : Hinkle Creek paired watershed study Author: Otis, Timothy Leonard This research investigates the direct and downstream impacts of clearcut harvest units on stream temperature as a part of the Hinkle Creek Paired Watershed Study. The Hinkle Creek watershed is located in the foothills of the Cascade Mountains about 30 kilometers northeast of Roseburg, Oregon, is privately owned, and supports a 60-year old, harvest-regenerated, Douglas-fir forest. The study watershed contains four treatment and two control sub-watersheds within the larger treatment and control watersheds, respectively. The first harvest entry, which took place during the winter 2005–2006, consisted of five clearcut harvest units located adjacent to perennial, non-fish-bearing streams. One year each of calibration and post-harvest data are analyzed. The experimental design for the study was a Before-After-Control-Impact (BACI) design. Maximum daily stream temperatures (MDST) were analyzed for the four treatment streams for one year before and one year after harvest. A multiple linear regression model was used to compare the 2005 data with the 2006 data for each stream. Stream temperature data from Myers Creek (temperature probe C04) was the control. The model for this analysis was: yt = μ +α + βx + ε where yt is the temperature of the stream on a day t, μ is the overall mean value of y, αi is the effect of year, xt is the corresponding temperature of the control stream on a day t, β is the coefficient estimated by regression, and εt is the error term. This method is an analysis of variance of values that are adjusted for regression with an independent variable, in this case the maximum daily temperatures of the control stream. The impact of timber harvest on MDST is small when compared to the spatial (between-stream) variation in MDST and this impact decreased downstream. At 300 meters, nominally, downstream of the harvest units the impact of timber harvest on MDST was not statistically significant for two streams and only moderately statistically significant for the other two streams. Stream velocity, discharge, and groundwater advection in the streams downstream of the harvest units were quantified using dye tracer dilution techniques. The One-dimensional Transport with Inflow and Storage (OTIS) model was used to quantify longitudinal dispersions, transient storage volumes, storage transfer rates, and hyporheic residence times in four 75 meter reaches in each of the four treatment streams. Stream velocities calculated with OTIS ranged from 0.24 to 0.40 m/sec for the four streams. Dispersions ranged from 0.18 and 0.84 m2/sec. The estimated crosssectional area of the ‘immobile’ zones of water storage divided by the stream cross-sectional area, As/A or the storage ratio, varied from near zero to 7.2. The residence times of water in hyporheic storage ranged from 2.3 hrs to 32 hrs. Water stored in a shaded reach of stream, in pools, and in hyporheic zones provides a volume of water that can be exchanged with the water in the active stream channel. This provides for physical mixing with cooler water and heat transfer to the stream bed. Latent heat, Sensible heat, Longwave Radiant heat and Photosynthetically Active Radiation (PAR) were calculated for August 7-17, 2006 at the center of the 300 meter study reach in Russell Creek. The air temperature was lower than stream temperature during four of those nights and the stream cooled due to a net loss of longwave radiation and evaporative cooling. Close

• 9. [Article] The influence of environmental and physical factors on the thermal patterns of headwater streams

  A case study was performed in 2000 and 2001 to characterize the thermal pattern of four morphologically similar eastern Oregon streams and to identify the physical and environmental factors that expressed ...

  Citation × Citation Citation Abstract Copy Title: The influence of environmental and physical factors on the thermal patterns of headwater streams Author: Carr, Craig A. A case study was performed in 2000 and 2001 to characterize the thermal pattern of four morphologically similar eastern Oregon streams and to identify the physical and environmental factors that expressed significant and functionally viable relationships with stream temperature (daily maximum, daily minimum and daily rate of heating). Stream and environmental attributes were measured at various locations along each stream to provide a data set comprised of variables representing daily stream temperatures (minimum, maximum and rates of heating), daily air temperatures (minimum and maximum), shade, elevation, elevation change and length. Data from the 20 hottest days were analyzed using analysis of variance and regression-based path analysis. With the exception of those reaches that were influenced by groundwater or subsurface flow, downstream reaches consistently experienced increases in the daily maximum stream temperature. The most significant parameter with respect to daily maximum stream temperature appeared to be reach elevation; expressed through reach location in the watershed. Maximum air temperature also positively influenced maximum stream temperature however, only on streams that expressed significant variation in maximum air temperature. The dominant influence of groundwater on maximum stream temperature was also apparent. Significant reach level variation in daily minimum stream temperatures was not observed in this study, however most streams did record increases in the downstream direction. Daily minimum air temperature was consistent across all streams in expressing the most significant relationship with daily minimum stream temperature. With the exception of groundwater influenced reaches, all streams exhibited obvious downstream increases in the daily rate of stream heating. Daily minimum air temperature consistently exhibited a significant negative association with the rate of heating and a relationship was also implied between reach elevation, maximum stream temperature and minimum stream temperature and this stream temperature response. Groundwater and subsurface flow, when present, also appeared to influence the daily rate of stream heating. Resource management activities should have little impact on the parameters found, on these streams, to be associated with stream temperature. Location in the watershed and climatic influence through both minimum and maximum air temperatures emerged as the dominant factors with respect to stream thermal patterns. Title: The influence of environmental and physical factors on the thermal patterns of headwater streams Author: Carr, Craig A. A case study was performed in 2000 and 2001 to characterize the thermal pattern of four morphologically similar eastern Oregon streams and to identify the physical and environmental factors that expressed significant and functionally viable relationships with stream temperature (daily maximum, daily minimum and daily rate of heating). Stream and environmental attributes were measured at various locations along each stream to provide a data set comprised of variables representing daily stream temperatures (minimum, maximum and rates of heating), daily air temperatures (minimum and maximum), shade, elevation, elevation change and length. Data from the 20 hottest days were analyzed using analysis of variance and regression-based path analysis. With the exception of those reaches that were influenced by groundwater or subsurface flow, downstream reaches consistently experienced increases in the daily maximum stream temperature. The most significant parameter with respect to daily maximum stream temperature appeared to be reach elevation; expressed through reach location in the watershed. Maximum air temperature also positively influenced maximum stream temperature however, only on streams that expressed significant variation in maximum air temperature. The dominant influence of groundwater on maximum stream temperature was also apparent. Significant reach level variation in daily minimum stream temperatures was not observed in this study, however most streams did record increases in the downstream direction. Daily minimum air temperature was consistent across all streams in expressing the most significant relationship with daily minimum stream temperature. With the exception of groundwater influenced reaches, all streams exhibited obvious downstream increases in the daily rate of stream heating. Daily minimum air temperature consistently exhibited a significant negative association with the rate of heating and a relationship was also implied between reach elevation, maximum stream temperature and minimum stream temperature and this stream temperature response. Groundwater and subsurface flow, when present, also appeared to influence the daily rate of stream heating. Resource management activities should have little impact on the parameters found, on these streams, to be associated with stream temperature. Location in the watershed and climatic influence through both minimum and maximum air temperatures emerged as the dominant factors with respect to stream thermal patterns. Close

• 10. [Article] Mass erosion occurrence and debris torrent impacts on some streams in the Willamette National Forest

  This study focused on extensive soil mass movement occurrence in the Willamette National Forest of western Oregon and on intensive measurements of some physical and biological changes in streams following ...

  Citation × Citation Citation Abstract Copy Title: Mass erosion occurrence and debris torrent impacts on some streams in the Willamette National Forest Author: Chesney, Charles J. This study focused on extensive soil mass movement occurrence in the Willamette National Forest of western Oregon and on intensive measurements of some physical and biological changes in streams following debris torrents. Debris torrents are a rapid movement of water-charged debris confined to steep headwater channels. The frequency (events/ha/yr) of mass failures identified from aerial photos increased in the presence of clearcuts and roads relative to forest conditions. Approximately 71% of hillslope mass failures entered the stream channel, and an estimated 43% of hillslope mass failures resulted in debris torrents. Standing crop of large organic debris and annual input to streams affected by debris torrents were highly variable. Silvicultural conditions of upslope vegetation and morphological features of debris torrent tracks influenced woody loading and input. Old-growth streams and depositional stream sites contained higher amounts of large organic debris and received higher inputs of large organic debris than streams in clearcuts and erosional stream sites. Depositional sites along debris torrent tracks have higher pool area and depth relative to erosional stream sites. Stream channel gradient and channel cross-sectional form influence the character of erosional or depositional sites sluiced by a debris torrent. Higher total pool ratings in depositional stream sites indicate spatial complexity of channel form that is related to the availability, transport, and stability of particulate bed materials. Herbs produced the majority of foliar biomass (> 50% of total) in one-fifth of all stream sites. Shrubs produced the majority of foliar biomass in one-third of all stream sites. Stream sites where estimated foliar biomass of post-torrent plant strata exceeded estimated foliar biomass of residual plant strata were more numerous. Successional changes in clearcut riparian zones included a shift to intolerant deciduous overstory species and more numerous shrub species than in old-growth riparian zones. The diameter growth of tolerant late successional overstory species in these riparian zones was inconsistent, whereas diameter growth of early successional species was rapid. Case studies of two streams permitted analysis of riparian recovery relative to that of an undisturbed stream site upstream of the debris torrent track. Warfield Creek is a stream where a high energy debris torrent remarkably altered stream conditions. Simmonds Creek is a stream where a low energy debris torrent imperceptibly changed stream conditions. Channel slope, channel cross-sectional form, severity of debris torrent, position of stream segment within the drainage, and presence of channel obstructions all affect stream response to debris torrents, as do riparian vegetation and litterfall inputs to the stream. Riparian recovery remains difficult to quantify because of physical and biological structures of stream ecosystems that vary in space and time. Title: Mass erosion occurrence and debris torrent impacts on some streams in the Willamette National Forest Author: Chesney, Charles J. This study focused on extensive soil mass movement occurrence in the Willamette National Forest of western Oregon and on intensive measurements of some physical and biological changes in streams following debris torrents. Debris torrents are a rapid movement of water-charged debris confined to steep headwater channels. The frequency (events/ha/yr) of mass failures identified from aerial photos increased in the presence of clearcuts and roads relative to forest conditions. Approximately 71% of hillslope mass failures entered the stream channel, and an estimated 43% of hillslope mass failures resulted in debris torrents. Standing crop of large organic debris and annual input to streams affected by debris torrents were highly variable. Silvicultural conditions of upslope vegetation and morphological features of debris torrent tracks influenced woody loading and input. Old-growth streams and depositional stream sites contained higher amounts of large organic debris and received higher inputs of large organic debris than streams in clearcuts and erosional stream sites. Depositional sites along debris torrent tracks have higher pool area and depth relative to erosional stream sites. Stream channel gradient and channel cross-sectional form influence the character of erosional or depositional sites sluiced by a debris torrent. Higher total pool ratings in depositional stream sites indicate spatial complexity of channel form that is related to the availability, transport, and stability of particulate bed materials. Herbs produced the majority of foliar biomass (> 50% of total) in one-fifth of all stream sites. Shrubs produced the majority of foliar biomass in one-third of all stream sites. Stream sites where estimated foliar biomass of post-torrent plant strata exceeded estimated foliar biomass of residual plant strata were more numerous. Successional changes in clearcut riparian zones included a shift to intolerant deciduous overstory species and more numerous shrub species than in old-growth riparian zones. The diameter growth of tolerant late successional overstory species in these riparian zones was inconsistent, whereas diameter growth of early successional species was rapid. Case studies of two streams permitted analysis of riparian recovery relative to that of an undisturbed stream site upstream of the debris torrent track. Warfield Creek is a stream where a high energy debris torrent remarkably altered stream conditions. Simmonds Creek is a stream where a low energy debris torrent imperceptibly changed stream conditions. Channel slope, channel cross-sectional form, severity of debris torrent, position of stream segment within the drainage, and presence of channel obstructions all affect stream response to debris torrents, as do riparian vegetation and litterfall inputs to the stream. Riparian recovery remains difficult to quantify because of physical and biological structures of stream ecosystems that vary in space and time. Close