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• 531. [Article] Essays on conservation policies and agricultural nonpoint source pollution control

  This dissertation consists of three papers on agricultural nonpoint source pollution and control. The first paper focuses primarily on agricultural land use changes under alternative conservation policies. ...

  Citation × Citation Citation Abstract Copy Title: Essays on conservation policies and agricultural nonpoint source pollution control Author: Tanaka, Katsuya This dissertation consists of three papers on agricultural nonpoint source pollution and control. The first paper focuses primarily on agricultural land use changes under alternative conservation policies. The second and third papers address environmental implications of these policies and their cost effectiveness. In the first paper, the effect of alternative conservation policies on agricultural land use in the Upper Mississippi River Basin is quantitatively evaluated. Site-specific land use decisions are analyzed using a set of discrete choice models and site-specific economic and physical information. The models are then used to predict farmers' choice of crop, crop rotation, and participation in the Conservation Reserve Program under alternative conservation policies. Results suggest that acreage planted to "polluting" crops (corn and soybean) are quite responsive to the fertilizer-use tax, but not quite as responsive to the two payment programs considered in this paper. In the second paper, the social costs of alternative conservation policies are estimated for reducing nitrate-N concentrations in the Upper Mississippi River. This objective is achieved by developing an integrated modeling framework consisting of economic and physical models. Results suggest that the nitrogen fertilizer-use tax is much more cost effective than the three payment programs. Incentive payments for conservation tillage are most cost effective among the three payment programs, but can only reduce nitrate-N concentrations to a limited level. The potential of incentive payments for corn-soybean rotation is even more limited. Although the Conservation Reserve Program can achieve the highest level of nitrate-N concentrations reduction, it imposes the highest cost to society. In the third paper, the relative efficiency between the targeted and uniform fertilizer-use taxes for reducing agricultural water pollution is estimated. This paper adds some refinements to the integrated model developed in the second paper, for assessing nitrate-N runoff from the 9 subbasins in the Des Moines Watershed. In contrast to previous studies, results in this paper suggest that the targeted fertilizer-use tax outperforms the uniform tax under spatially heterogeneous conditions. The targeted fertilizer-use tax reduces the aggregate farm profit loss under the uniform tax by up to 30 percent in this watershed. Title: Essays on conservation policies and agricultural nonpoint source pollution control Author: Tanaka, Katsuya This dissertation consists of three papers on agricultural nonpoint source pollution and control. The first paper focuses primarily on agricultural land use changes under alternative conservation policies. The second and third papers address environmental implications of these policies and their cost effectiveness. In the first paper, the effect of alternative conservation policies on agricultural land use in the Upper Mississippi River Basin is quantitatively evaluated. Site-specific land use decisions are analyzed using a set of discrete choice models and site-specific economic and physical information. The models are then used to predict farmers' choice of crop, crop rotation, and participation in the Conservation Reserve Program under alternative conservation policies. Results suggest that acreage planted to "polluting" crops (corn and soybean) are quite responsive to the fertilizer-use tax, but not quite as responsive to the two payment programs considered in this paper. In the second paper, the social costs of alternative conservation policies are estimated for reducing nitrate-N concentrations in the Upper Mississippi River. This objective is achieved by developing an integrated modeling framework consisting of economic and physical models. Results suggest that the nitrogen fertilizer-use tax is much more cost effective than the three payment programs. Incentive payments for conservation tillage are most cost effective among the three payment programs, but can only reduce nitrate-N concentrations to a limited level. The potential of incentive payments for corn-soybean rotation is even more limited. Although the Conservation Reserve Program can achieve the highest level of nitrate-N concentrations reduction, it imposes the highest cost to society. In the third paper, the relative efficiency between the targeted and uniform fertilizer-use taxes for reducing agricultural water pollution is estimated. This paper adds some refinements to the integrated model developed in the second paper, for assessing nitrate-N runoff from the 9 subbasins in the Des Moines Watershed. In contrast to previous studies, results in this paper suggest that the targeted fertilizer-use tax outperforms the uniform tax under spatially heterogeneous conditions. The targeted fertilizer-use tax reduces the aggregate farm profit loss under the uniform tax by up to 30 percent in this watershed. Close

• 532. [Article] Comparisons of fish assemblages and habitat associations in littoral zones of reservoirs in the Willamette Basin, Oregon

  The littoral zones of seven reservoirs in the southern Willamette Valley of Oregon were sampled with a boat electroshocker during the summer months of 1995 and 1996. Shoreline substrates were inventoried ...

  Citation × Citation Citation Abstract Copy Title: Comparisons of fish assemblages and habitat associations in littoral zones of reservoirs in the Willamette Basin, Oregon Author: Bennett, Paul Michael The littoral zones of seven reservoirs in the southern Willamette Valley of Oregon were sampled with a boat electroshocker during the summer months of 1995 and 1996. Shoreline substrates were inventoried before sampling sites were randomly selected. Sampling sites consisted of 9 of 12 possible habitat types including four substrate types (bedrock, fines, gravel to small boulders, and large boulders), each with or without overlying vegetation or wood. Fish assemblages occupying these specific habitat types were compared. Various aspects of substrate distribution and dimensions were utilized to help explain differences in fish assemblages. Significant differences in richness, diversity, mean length, mean weight, and catch per unit effort (CPUE) of fish assemblages occupying the specific habitat types were found. Fish assemblages using vegetated substrates were greatest in richness, diversity, and CPUE, while bedrock and unvegetated fines were lowest. Gravel to small boulder substrates tended to be intermediate for these variables. Large boulder substrates were consistently on the higher end of the range of these values. The largest and oldest fish occupied habitats with wood and large boulder substrates; smaller, younger individuals tended to be found in fine substrates with vegetation. Largemouth bass, bluegill, and coarsescale suckers were well distributed across habitat types. Other species such as the yellow bullhead, white crappie, reticulate sculpin, longnose dace, and speckled dace were much more restricted in their use of habitat. Overlying structure tended to increase fish diversity and richness for fine but not for coarse size substrates. Comparison of fish species between reservoirs, using regression analysis, was also performed. Fish sampled in Lookout Point Reservoir showed the overall greatest weight for length values, whereas, fish from Hills Creek and Green Peter Reservoirs were lowest in these values of the seven study reservoirs. Regression analysis of specified substrate parameters to fish species richness and diversity indicated bedrock was generally a negative influence. The occurence of gravel to small boulder substrate was a positive influence over the range of segment sizes encountered. Large expanses of fines resulted in depressed richness and diversity. Conversely, smaller segments of fine habitat appear to have a strong positive effect on fish richness and diversity. Large boulders were found in too small a quantity to impact reservoir littoral zone fish assemblages. The exotic/native ratio of fish abundance averaged about 3/1 in all habitats sampled except fine substrates without overlying structure. Only here were native fish more abundant than exotics. Title: Comparisons of fish assemblages and habitat associations in littoral zones of reservoirs in the Willamette Basin, Oregon Author: Bennett, Paul Michael The littoral zones of seven reservoirs in the southern Willamette Valley of Oregon were sampled with a boat electroshocker during the summer months of 1995 and 1996. Shoreline substrates were inventoried before sampling sites were randomly selected. Sampling sites consisted of 9 of 12 possible habitat types including four substrate types (bedrock, fines, gravel to small boulders, and large boulders), each with or without overlying vegetation or wood. Fish assemblages occupying these specific habitat types were compared. Various aspects of substrate distribution and dimensions were utilized to help explain differences in fish assemblages. Significant differences in richness, diversity, mean length, mean weight, and catch per unit effort (CPUE) of fish assemblages occupying the specific habitat types were found. Fish assemblages using vegetated substrates were greatest in richness, diversity, and CPUE, while bedrock and unvegetated fines were lowest. Gravel to small boulder substrates tended to be intermediate for these variables. Large boulder substrates were consistently on the higher end of the range of these values. The largest and oldest fish occupied habitats with wood and large boulder substrates; smaller, younger individuals tended to be found in fine substrates with vegetation. Largemouth bass, bluegill, and coarsescale suckers were well distributed across habitat types. Other species such as the yellow bullhead, white crappie, reticulate sculpin, longnose dace, and speckled dace were much more restricted in their use of habitat. Overlying structure tended to increase fish diversity and richness for fine but not for coarse size substrates. Comparison of fish species between reservoirs, using regression analysis, was also performed. Fish sampled in Lookout Point Reservoir showed the overall greatest weight for length values, whereas, fish from Hills Creek and Green Peter Reservoirs were lowest in these values of the seven study reservoirs. Regression analysis of specified substrate parameters to fish species richness and diversity indicated bedrock was generally a negative influence. The occurence of gravel to small boulder substrate was a positive influence over the range of segment sizes encountered. Large expanses of fines resulted in depressed richness and diversity. Conversely, smaller segments of fine habitat appear to have a strong positive effect on fish richness and diversity. Large boulders were found in too small a quantity to impact reservoir littoral zone fish assemblages. The exotic/native ratio of fish abundance averaged about 3/1 in all habitats sampled except fine substrates without overlying structure. Only here were native fish more abundant than exotics. Close

• 533. [Article] Biology and management of Meloidogyne chitwoodi using oxamyl on potato in the western United States

  Field trials were conducted during 2001 to 2003 to investigate soil population dynamics of Meloidogyne chitwoodi, tuber symptom suppression using oxamyl, and post-harvest tuber symptom development on short-season ...

  Citation × Citation Citation Abstract Copy Title: Biology and management of Meloidogyne chitwoodi using oxamyl on potato in the western United States Author: David, Nicholas L. Field trials were conducted during 2001 to 2003 to investigate soil population dynamics of Meloidogyne chitwoodi, tuber symptom suppression using oxamyl, and post-harvest tuber symptom development on short-season potato varieties Russet Norkotah and Russet Nugget (San Luis Valley only). The experiments were located in the San Luis Valley in Colorado, Klamath Basin in Oregon, and southern Columbia Basin in Oregon to represent, cool, warm, and hot growing regions, respectively. M. chitwoodi soil population dynamics were multi-modal in all three regions representing distinct periods of egg hatch and root and tuber infection. M. chitwoodi completed two generations in the cooler production areas of the Klamath Basin and San Luis Valley, and three generations in the hot region of the Columbia Basin. When left uncontrolled, M. chitwoodi infected and caused tuber symptoms in all three regions, but tuber symptoms were significantly reduced with the use of a bi-weekly oxamyl program that began at the hatch of the second generation. Furthermore, augmenting with in-furrow at-planting and crop emergence applications provided better protection. The level of reduction in symptoms using the application schedules outlined in this research was substantially better than that previously observed with this nematicide. Oxamyl did not control M. chitwoodi densities in the soil. For that reason, internal and external symptoms increased when harvest was delayed by three weeks in the Columbia Basin regardless of whether or not oxamyl had been applied. Following harvest in the Columbia Basin and Klamath Basin there is potential for internal symptom development if tubers are stored warm. The percentage of tubers with internal symptoms increased when stored at 21-24°C and more than 740 post-harvest DD5C were accumulated, regardless of whether or not oxamyl was used. However internal symptoms did not increase during long-term cold storage (3-5°C) when no more than 480 – 610 post-harvest DD5C were accumulated. Unlike internal symptoms, there was no increase in external symptoms following harvest even when as many as 1,000 post-harvest DD5C were accumulated. Oxamyl is currently the only chemical that growers can apply during the growing season to suppress tuber damage from M. chitwoodi and reduces symptoms on short-season potato cultivars in both cool and hot growing regions in the western United States. Title: Biology and management of Meloidogyne chitwoodi using oxamyl on potato in the western United States Author: David, Nicholas L. Field trials were conducted during 2001 to 2003 to investigate soil population dynamics of Meloidogyne chitwoodi, tuber symptom suppression using oxamyl, and post-harvest tuber symptom development on short-season potato varieties Russet Norkotah and Russet Nugget (San Luis Valley only). The experiments were located in the San Luis Valley in Colorado, Klamath Basin in Oregon, and southern Columbia Basin in Oregon to represent, cool, warm, and hot growing regions, respectively. M. chitwoodi soil population dynamics were multi-modal in all three regions representing distinct periods of egg hatch and root and tuber infection. M. chitwoodi completed two generations in the cooler production areas of the Klamath Basin and San Luis Valley, and three generations in the hot region of the Columbia Basin. When left uncontrolled, M. chitwoodi infected and caused tuber symptoms in all three regions, but tuber symptoms were significantly reduced with the use of a bi-weekly oxamyl program that began at the hatch of the second generation. Furthermore, augmenting with in-furrow at-planting and crop emergence applications provided better protection. The level of reduction in symptoms using the application schedules outlined in this research was substantially better than that previously observed with this nematicide. Oxamyl did not control M. chitwoodi densities in the soil. For that reason, internal and external symptoms increased when harvest was delayed by three weeks in the Columbia Basin regardless of whether or not oxamyl had been applied. Following harvest in the Columbia Basin and Klamath Basin there is potential for internal symptom development if tubers are stored warm. The percentage of tubers with internal symptoms increased when stored at 21-24°C and more than 740 post-harvest DD5C were accumulated, regardless of whether or not oxamyl was used. However internal symptoms did not increase during long-term cold storage (3-5°C) when no more than 480 – 610 post-harvest DD5C were accumulated. Unlike internal symptoms, there was no increase in external symptoms following harvest even when as many as 1,000 post-harvest DD5C were accumulated. Oxamyl is currently the only chemical that growers can apply during the growing season to suppress tuber damage from M. chitwoodi and reduces symptoms on short-season potato cultivars in both cool and hot growing regions in the western United States. Close

• 534. [Article] Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin

  Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has ...

  Citation × Citation Citation Abstract Copy Title: Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin Author: Eiler, John H. Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has raised concerns over the future status of the returns, and severely impacted commercial and subsistence fisheries within the drainage. Management is further complicated by the mixed-stock composition of the run, the presence of other temporally similar salmon species, and the need to equitably allocate harvests between the numerous fisheries and user groups scattered throughout the basin. Detailed information is needed on Chinook salmon run characteristics to better understand and manage the returns, and facilitate conservation efforts. However, this goal is exacerbated by the massive size and remote nature of the basin, the large number of highly mobile fish, and the compressed timing of the run. To address these challenges, radio telemetry was used to determine the stock composition and spawning distribution of the returns, and the migratory characteristics of the fish. The migratory patterns exhibited by returning salmon provide a number of insights into the status of the run. Since the Yukon River is essentially free-flowing (i.e., not regulated), this study also presented an opportunity to document the distribution and upriver movements of large returns of wild Chinook salmon under natural conditions. During 2002-2004, returning adult Chinook salmon were captured in the lower Yukon River (approximately 300 km upriver from the river mouth), tagged with radio transmitters, and tracked upriver using remote tracking stations located on important migratory routes and major spawning tributaries. Aerial tracking surveys were used to locate fish in spawning areas and between stations. The fish responded well to the capture and handling procedures, with most (2,790, 98%) resuming upriver movements. Although the fish initially displayed a negative tagging response, with slower migration rates observed immediately after release, the duration of this response was relatively short (several days) and less severe as the fish moved upriver. Independent measures indicated that the swimming speeds and timing of the fish upriver from the tagging area were comparable to untagged fish, suggesting that the tagging methods used were relatively benign. Fish returned to spawning areas throughout the basin, ranging from several hundred to over 3,000 km from the tagging area. Distribution patterns were similar across years, suggesting that the principal components of the run were identified. Most spawning fish were clustered in a number of key tributaries, with smaller numbers of fish located in other spatially isolated areas. The fish typically returned to clear water tributaries that were relatively entrenched, had moderate gradients, and were associated with upland areas. Fish were largely absent in lowland reaches characterized by meandering, low gradient, highly alluvial channels often associated with main river floodplains. There was suggestive evidence of mainstem spawning in reaches of the Upper Yukon. The status of fish remaining in other mainstem areas was less certain, and may represent local spawning activity or fish that died while in-transit to upriver areas. Although Chinook salmon spawned throughout the basin, the run was dominated by two regional components (Tanana and Upper Yukon), which annually comprised over 70% of the return. Substantially fewer fish returned to other areas ranging from 2-9% of the return, although the collective contribution of these stocks was appreciable. Most regional returns consisted of several principal stocks and a number of small, spatially isolated populations. Regional and stock composition estimates were similar across years even though differences in run abundance were reported, suggesting that these abundance differences were not related to regional or stock-specific differences. Run timing was relatively compressed compared to rivers in the southern portion of the range, with most stocks passing through the lower river over a 6-week period, ranging from 16 to 38 d. Run timing was generally earlier for stocks traveling farther upriver, although exceptions were noted. Lower basin stocks were primarily later run fish. Pronounced differences were observed in the migration rates (km/d) exhibited by regional stocks. Substantially slower swimming speeds were observed for fish returning to terminal tributaries in the lower basin ranging from 28-40 km/d compared to 52-62 km/d for upper basin stocks. The migratory patterns (migration rates in sequential reaches) of the fish also showed distinct regional differences. Average migration rates through the lower river were remarkably similar for the different stocks, ranging from 57-62 km/d, with most stocks exhibiting a general decline as the fish moved farther upriver. Tanana River stocks displayed a pronounced reduction in swimming speed after leaving the Yukon River main stem, with migration rates declining to 24 km/d on average as the fish approached their terminal tributaries. Conversely, upper basin stocks exhibited a relatively gradual (but variable) overall decline in migration rate even though these fish were traveling substantially greater distances upriver. Average migration rates for upper basin stocks ranged from 43-61 km/d as the fish approached their terminal tributaries. There was substantial variation in the migratory patterns exhibited by individual fish, although these patterns tended to be similar to the patterns exhibited by the regional stocks, particularly as the fish moved farther upriver from the tagging area. The dominant source of variation among fish reflected the average migration rate, with individual fish traveling slower in the lower basin exhibiting consistently slower migration rates as they moved upriver compared to their faster moving counterparts. This migratory pattern was consistent across stocks, and on average explained 74% of the within-stock variation in migration rate represented by the multivariate data. The second source of variation in migration rate reflected a shift in the relative swimming speeds of the individual fish as they progressed upriver. Although movement rates declined for nearly all of the fish during the migration, differences were observed in the pattern of the decline. Fish with faster migration rates in the lower river exhibited a pronounced decline in swimming speed as they moved upriver, whereas fish moving slower in the lower river displayed a more gradual decline in migration rate. On average, this migratory pattern explained 22% of the within-stock variation in migration rate represented by the multivariate data. Most fish (98%) exhibited continuous upriver movements and strong fidelity to the rivers they entered. However a small number of fish (n = 66) deviated from this pattern. Some of these individuals initially passed their final destination and continued upriver for varying distances before reversing direction, swimming back downstream, and entering their terminal tributary. Although most of these excursions were relatively short (< 30 km), there were several instances where fish traveled hundreds of kilometers out of their way. Thirty-four fish tracked to terminal tributaries subsequently left these rivers, and traveled to other terminal tributaries within the basin (n = 31) or were harvested in upriver fisheries (n = 3). Although most of these incidents involved nearby tributaries, major diversions were also observed, with several fish traveling over 300 km to natal rivers after leaving the initial tributary. Chinook salmon returns to the Yukon River typically consisted of a series of distinct and sizable increases in the number fish entering the river over the course of the run, commonly referred to as pulses. A large number of fish (n = 251) were radio tagged over a 4-day period during a pulse in 2003 to provide information on the progression of the pulse as it moved upriver. The time taken by the pulse to move past subsequent upriver locations increased as the fish moved farther upriver from the tagging area, with the fish passing sites located 580 and 800 km upriver over a span of 14 and 21 d, respectively. Although not surprising considering the extensive variation in migration rates observed among individual fish, this finding does suggest that these pulses do not represent cohesive aggregates of fish moving upriver. Unlike the well established methods used to estimate other life history characteristics, the development of quantitative methods for analyzing and modeling fish movements has lagged noticeably behind, due in part to the complexity associated with movement data and (prior to the advent of telemetry) the difficulty of collecting this type of information on free-ranging individuals. Two fundamentally different analytical approaches, hierarchical linear regression models and multivariate ordination, were used during this study to evaluate factors thought to influence the upriver movements of the fish. In spite of the inherent differences, both methods provided strikingly similar results, indicating that the study findings were not dependent on the approach used, and suggesting that the results were plausible based on the information available and the weight of evidence. Both analytical methods had advantages, and provided complementary information. With hierarchical linear models, it was possible to simultaneously evaluate a wide range of explanatory variables (in our case, both biological and environmental), which provided standardized comparisons and simplified the interpretation of the results. Since both fixed and random effects were incorporated in the models, it was possible to account for sources of variation when insufficient information was available to identify the underlining factors – an important consideration since few field studies provide comprehensive data. With multivariate ordination, separate analyzes were needed to examine the relationships between the migration rates and the biotic and physical variables. In addition to being cumbersome, this limitation made it more difficult to compare the relative influence of the different factors and interactions between factors. However, ordination was very useful as an exploratory tool. Although compartmentalized by stock, across fish comparisons were simple and relatively straightforward. Because the explanatory variables were evaluated separately in relation to the ordination score assigned to the fish, it was possible to examine and compare highly correlated variables. Ordination was also able to identify overall patterns within the data and assess the relative importance. While this can be accomplished within the framework of linear regression using mixture models to determine whether multiple distributions exist within the data, the process is much simpler with ordination. The migratory patterns of the fish were influenced by a wide range of factors, with evidentiary support for complex, multi-faceted relationships. Physical features of the basin demonstrated stronger explanatory power, accounting for over 70% of the observed variation in migration rate compared to 18% for the biological characteristics of the fish. Parameter estimates associated with the steepness of the migratory route and remaining distance the fish had to travel to reach their natal rivers were most strongly correlated with migration rate, with consistent relationships observed across stocks. Migration rates were also noticeably slower in extensively braided reaches of the basin. The weaker relationships between migration rate and biotic factors may reflect stabilizing selection on long-distance migrants. Smaller fish exhibited minimally faster swimming speeds on average than larger individuals. This relationship was stronger in highly braided reaches. Run timing was positively related to migration rate for most stocks. Surprisingly, upper basin stocks traveling farther upriver displayed progressively negative relationships, suggesting that late-run fish were moving slower. Ancillary information suggests that this decline may relate to deteriorating fish condition later in the season. Title: Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin Author: Eiler, John H. Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has raised concerns over the future status of the returns, and severely impacted commercial and subsistence fisheries within the drainage. Management is further complicated by the mixed-stock composition of the run, the presence of other temporally similar salmon species, and the need to equitably allocate harvests between the numerous fisheries and user groups scattered throughout the basin. Detailed information is needed on Chinook salmon run characteristics to better understand and manage the returns, and facilitate conservation efforts. However, this goal is exacerbated by the massive size and remote nature of the basin, the large number of highly mobile fish, and the compressed timing of the run. To address these challenges, radio telemetry was used to determine the stock composition and spawning distribution of the returns, and the migratory characteristics of the fish. The migratory patterns exhibited by returning salmon provide a number of insights into the status of the run. Since the Yukon River is essentially free-flowing (i.e., not regulated), this study also presented an opportunity to document the distribution and upriver movements of large returns of wild Chinook salmon under natural conditions. During 2002-2004, returning adult Chinook salmon were captured in the lower Yukon River (approximately 300 km upriver from the river mouth), tagged with radio transmitters, and tracked upriver using remote tracking stations located on important migratory routes and major spawning tributaries. Aerial tracking surveys were used to locate fish in spawning areas and between stations. The fish responded well to the capture and handling procedures, with most (2,790, 98%) resuming upriver movements. Although the fish initially displayed a negative tagging response, with slower migration rates observed immediately after release, the duration of this response was relatively short (several days) and less severe as the fish moved upriver. Independent measures indicated that the swimming speeds and timing of the fish upriver from the tagging area were comparable to untagged fish, suggesting that the tagging methods used were relatively benign. Fish returned to spawning areas throughout the basin, ranging from several hundred to over 3,000 km from the tagging area. Distribution patterns were similar across years, suggesting that the principal components of the run were identified. Most spawning fish were clustered in a number of key tributaries, with smaller numbers of fish located in other spatially isolated areas. The fish typically returned to clear water tributaries that were relatively entrenched, had moderate gradients, and were associated with upland areas. Fish were largely absent in lowland reaches characterized by meandering, low gradient, highly alluvial channels often associated with main river floodplains. There was suggestive evidence of mainstem spawning in reaches of the Upper Yukon. The status of fish remaining in other mainstem areas was less certain, and may represent local spawning activity or fish that died while in-transit to upriver areas. Although Chinook salmon spawned throughout the basin, the run was dominated by two regional components (Tanana and Upper Yukon), which annually comprised over 70% of the return. Substantially fewer fish returned to other areas ranging from 2-9% of the return, although the collective contribution of these stocks was appreciable. Most regional returns consisted of several principal stocks and a number of small, spatially isolated populations. Regional and stock composition estimates were similar across years even though differences in run abundance were reported, suggesting that these abundance differences were not related to regional or stock-specific differences. Run timing was relatively compressed compared to rivers in the southern portion of the range, with most stocks passing through the lower river over a 6-week period, ranging from 16 to 38 d. Run timing was generally earlier for stocks traveling farther upriver, although exceptions were noted. Lower basin stocks were primarily later run fish. Pronounced differences were observed in the migration rates (km/d) exhibited by regional stocks. Substantially slower swimming speeds were observed for fish returning to terminal tributaries in the lower basin ranging from 28-40 km/d compared to 52-62 km/d for upper basin stocks. The migratory patterns (migration rates in sequential reaches) of the fish also showed distinct regional differences. Average migration rates through the lower river were remarkably similar for the different stocks, ranging from 57-62 km/d, with most stocks exhibiting a general decline as the fish moved farther upriver. Tanana River stocks displayed a pronounced reduction in swimming speed after leaving the Yukon River main stem, with migration rates declining to 24 km/d on average as the fish approached their terminal tributaries. Conversely, upper basin stocks exhibited a relatively gradual (but variable) overall decline in migration rate even though these fish were traveling substantially greater distances upriver. Average migration rates for upper basin stocks ranged from 43-61 km/d as the fish approached their terminal tributaries. There was substantial variation in the migratory patterns exhibited by individual fish, although these patterns tended to be similar to the patterns exhibited by the regional stocks, particularly as the fish moved farther upriver from the tagging area. The dominant source of variation among fish reflected the average migration rate, with individual fish traveling slower in the lower basin exhibiting consistently slower migration rates as they moved upriver compared to their faster moving counterparts. This migratory pattern was consistent across stocks, and on average explained 74% of the within-stock variation in migration rate represented by the multivariate data. The second source of variation in migration rate reflected a shift in the relative swimming speeds of the individual fish as they progressed upriver. Although movement rates declined for nearly all of the fish during the migration, differences were observed in the pattern of the decline. Fish with faster migration rates in the lower river exhibited a pronounced decline in swimming speed as they moved upriver, whereas fish moving slower in the lower river displayed a more gradual decline in migration rate. On average, this migratory pattern explained 22% of the within-stock variation in migration rate represented by the multivariate data. Most fish (98%) exhibited continuous upriver movements and strong fidelity to the rivers they entered. However a small number of fish (n = 66) deviated from this pattern. Some of these individuals initially passed their final destination and continued upriver for varying distances before reversing direction, swimming back downstream, and entering their terminal tributary. Although most of these excursions were relatively short (< 30 km), there were several instances where fish traveled hundreds of kilometers out of their way. Thirty-four fish tracked to terminal tributaries subsequently left these rivers, and traveled to other terminal tributaries within the basin (n = 31) or were harvested in upriver fisheries (n = 3). Although most of these incidents involved nearby tributaries, major diversions were also observed, with several fish traveling over 300 km to natal rivers after leaving the initial tributary. Chinook salmon returns to the Yukon River typically consisted of a series of distinct and sizable increases in the number fish entering the river over the course of the run, commonly referred to as pulses. A large number of fish (n = 251) were radio tagged over a 4-day period during a pulse in 2003 to provide information on the progression of the pulse as it moved upriver. The time taken by the pulse to move past subsequent upriver locations increased as the fish moved farther upriver from the tagging area, with the fish passing sites located 580 and 800 km upriver over a span of 14 and 21 d, respectively. Although not surprising considering the extensive variation in migration rates observed among individual fish, this finding does suggest that these pulses do not represent cohesive aggregates of fish moving upriver. Unlike the well established methods used to estimate other life history characteristics, the development of quantitative methods for analyzing and modeling fish movements has lagged noticeably behind, due in part to the complexity associated with movement data and (prior to the advent of telemetry) the difficulty of collecting this type of information on free-ranging individuals. Two fundamentally different analytical approaches, hierarchical linear regression models and multivariate ordination, were used during this study to evaluate factors thought to influence the upriver movements of the fish. In spite of the inherent differences, both methods provided strikingly similar results, indicating that the study findings were not dependent on the approach used, and suggesting that the results were plausible based on the information available and the weight of evidence. Both analytical methods had advantages, and provided complementary information. With hierarchical linear models, it was possible to simultaneously evaluate a wide range of explanatory variables (in our case, both biological and environmental), which provided standardized comparisons and simplified the interpretation of the results. Since both fixed and random effects were incorporated in the models, it was possible to account for sources of variation when insufficient information was available to identify the underlining factors – an important consideration since few field studies provide comprehensive data. With multivariate ordination, separate analyzes were needed to examine the relationships between the migration rates and the biotic and physical variables. In addition to being cumbersome, this limitation made it more difficult to compare the relative influence of the different factors and interactions between factors. However, ordination was very useful as an exploratory tool. Although compartmentalized by stock, across fish comparisons were simple and relatively straightforward. Because the explanatory variables were evaluated separately in relation to the ordination score assigned to the fish, it was possible to examine and compare highly correlated variables. Ordination was also able to identify overall patterns within the data and assess the relative importance. While this can be accomplished within the framework of linear regression using mixture models to determine whether multiple distributions exist within the data, the process is much simpler with ordination. The migratory patterns of the fish were influenced by a wide range of factors, with evidentiary support for complex, multi-faceted relationships. Physical features of the basin demonstrated stronger explanatory power, accounting for over 70% of the observed variation in migration rate compared to 18% for the biological characteristics of the fish. Parameter estimates associated with the steepness of the migratory route and remaining distance the fish had to travel to reach their natal rivers were most strongly correlated with migration rate, with consistent relationships observed across stocks. Migration rates were also noticeably slower in extensively braided reaches of the basin. The weaker relationships between migration rate and biotic factors may reflect stabilizing selection on long-distance migrants. Smaller fish exhibited minimally faster swimming speeds on average than larger individuals. This relationship was stronger in highly braided reaches. Run timing was positively related to migration rate for most stocks. Surprisingly, upper basin stocks traveling farther upriver displayed progressively negative relationships, suggesting that late-run fish were moving slower. Ancillary information suggests that this decline may relate to deteriorating fish condition later in the season. Close

• 535. [Article] Surface-subsurface geology of the middle to upper Eocene sedimentary and volcanic rock units, western Columbia County, northwest Oregon

  The middle to upper Eocene Tillamook Volcanics form the basement in the Rock Creek - Rocky Point area. These tholeiitic to alkalic basalts, basaltic andesites, and andesites were erupted as shield volcanoes ...

  Citation × Citation Citation Abstract Copy Title: Surface-subsurface geology of the middle to upper Eocene sedimentary and volcanic rock units, western Columbia County, northwest Oregon Author: Berkman, Thomas Anthony The middle to upper Eocene Tillamook Volcanics form the basement in the Rock Creek - Rocky Point area. These tholeiitic to alkalic basalts, basaltic andesites, and andesites were erupted as shield volcanoes seaward of the strandline ontop of an older deep-marine mudstone unit (Yamhill Formation) and an accreted portion of oceanic seafloor (lower Eocene Siletz River Volcanics). The subaerial flows are predominantly aphyric with subordinate plagioclase-augite porphyritic flows with pilotaxitic texture. The overlying Hamlet formation (informal) is composed of three members which document a marine transgression over subsiding islands of Tilamook Volcanics in the middle to late Eocene. The stratigraphically lowest Roy Creek member is composed of basaltic boulder to cobble conglomerate grading upward into fossiliferous pebbly basaltic sandstone deposited around sea stacks and along a high-energy rocky coastline composed of Tillamook Volcanics. Continued subsidence and transgression resulted in deposition of the Sunset Highway member of the Hamlet formation, which conformably overlies the Roy Creek member. The Sunset Highway member consists of interbedded micaceous arkosic sandstone and siltstone with rare basaltic grit beds occurring near the top of the member. Molluscan fauna, faint low-angle cross-bedding, parallel laminations and bioturbation in these sandstones are interpreted to represent deposition in a high-energy inner shelf environment. The upper Narizian (upper Eocene) Sweet Home Creek member conformably overlies the Sunset Highway member in western Columbia and eastern Clatsop counties and is composed of two lithofacies. The dominant lower facies consists of micromicaceous and carbonaceous silty mudstone which contains abundant Foraniinifera indicative of outer neritic to tipper bathyal water depths. Thin-bedded micaceous arkosic turbidite sandstones in nested channels of the upper facies are locally present near the top of the unit and represent deposits of a channelized shelf-slope break. Abrupt sea level regression coupled with increased sedimentation rates due to tectonic unroofing in source areas in Idaho and Washington resulted in abrupt shallowing of sedimentation before deposition of the overlying Cowlitz Formation (C & W sandstone member). The C & W sandstone in cores from the Mist Gas Field and outcrops in the Rock Creek - Rocky Point area in Columbia County consists of massive to hummocky bedded sandstone with some bioturbated siltstone and coal formed in a delta front complex ranging from brackish-water swamps to storm-wave-dominated lower shoreface environments. Sandstone onlaps basement highs of Tillamook Volcanics (Nehalem arch), resulting in a complicated facies geometry with some intrabasinal basaltic detritus. Sedimentary structures, statistical grain size analysis, and lithofacies associations suggest that strong wave processes reworked the delta front sands during a transgression at the seaward edge of the system. Thickening-upward and shallowing-upward sequences record periods of westward deltaic progradation and increasing storm-wave energy. C & W gas reservoirs consist of well-sorted, friable, fine-grained arkose to lithic arkose. Sandstone reservoir porosity and permeability average 31% and 1200 md, respectively. Porosity is dominated by primary intergranular pores which have been reduced by (1) compaction of ductile grains, (2) formation of minor mixed-layer clay rim cement, sparry calcite cement and authigenic pyrite, and (3) late stage precipitation of plagioclase, K-feldspar, and quartz overgrowths. However, partial dissolution of plagiociase feldspar has created some secondary porosity. Although arkosic sandstones have high porosities and correspondingly high permeabilities, chioritic cement in volcaniclastic-rich sandstones significantly reduces permeability without concomitant reduction in porosity. The Cole Mountain basalt (informal) locally intnides and overlies the Cowlitz Formation. These basalts to basaltic andesites have calc-alkaline affinities and consist of hypabyssal sills, submarine lava flows, and local peperites which are lithologically, chemically, and petrographically distinct from the slightly older Tillamook Volcanics. The uppermost Narizian to Refugian (latest Eocene) Keasey Formation unconfonnably overlies the Cowlitz Formation in the study area. Volcanic and glauconitic sandstones at the base of the Keasey Formation mark the unconformity and reflect a period of slow sedimentation under slightly reducing conditions. The Keasey Formation predominantly consists of stractureless, tuffaceous fossiliferous mudstone deposited by hemipelagic sedimentation on the middle to upper slope. The informal Miocene (?) Ivy Creek formation locally disconformably overlies the Keasey Formation in the study area. The fluvially deposited Ivy Creek formation consists of a friable upper trough cross-bedded pebbly sand fades which overlies 9 m of blue organic-rich overbank clay. Local pebbly grits in matrix-support with buried flow-oriented rooted tree stems suggest that some debris flows entered the fluvial system from surrounding highlands. The unit may correspond to the middle Miocene Scappoose Formation. Northwest-trending down-to-the-northeast high-angle faults, some with oblique offset, and a subordinate set of older east-trending faults are the dominant structural features of the Rock Creek - Rocky Point area. The faulting produces a dissected structural high or upthrown basement block of middle to upper Eocene Tillamook Volcanics. Upper Eocene sedimentary units flank the north and south sides with occasional perched sedimentary outliers along the volcanic crest. Although source rock evaluations from this study indicate that the upper Eocene samples are thermally immature, it is possible that thermogenic thy gas at Mist migrated updip from more deeply buried Cowlitz shales and coals or equivalent Eocene strata in the adjacent Tualatin and Astoria basins. Title: Surface-subsurface geology of the middle to upper Eocene sedimentary and volcanic rock units, western Columbia County, northwest Oregon Author: Berkman, Thomas Anthony The middle to upper Eocene Tillamook Volcanics form the basement in the Rock Creek - Rocky Point area. These tholeiitic to alkalic basalts, basaltic andesites, and andesites were erupted as shield volcanoes seaward of the strandline ontop of an older deep-marine mudstone unit (Yamhill Formation) and an accreted portion of oceanic seafloor (lower Eocene Siletz River Volcanics). The subaerial flows are predominantly aphyric with subordinate plagioclase-augite porphyritic flows with pilotaxitic texture. The overlying Hamlet formation (informal) is composed of three members which document a marine transgression over subsiding islands of Tilamook Volcanics in the middle to late Eocene. The stratigraphically lowest Roy Creek member is composed of basaltic boulder to cobble conglomerate grading upward into fossiliferous pebbly basaltic sandstone deposited around sea stacks and along a high-energy rocky coastline composed of Tillamook Volcanics. Continued subsidence and transgression resulted in deposition of the Sunset Highway member of the Hamlet formation, which conformably overlies the Roy Creek member. The Sunset Highway member consists of interbedded micaceous arkosic sandstone and siltstone with rare basaltic grit beds occurring near the top of the member. Molluscan fauna, faint low-angle cross-bedding, parallel laminations and bioturbation in these sandstones are interpreted to represent deposition in a high-energy inner shelf environment. The upper Narizian (upper Eocene) Sweet Home Creek member conformably overlies the Sunset Highway member in western Columbia and eastern Clatsop counties and is composed of two lithofacies. The dominant lower facies consists of micromicaceous and carbonaceous silty mudstone which contains abundant Foraniinifera indicative of outer neritic to tipper bathyal water depths. Thin-bedded micaceous arkosic turbidite sandstones in nested channels of the upper facies are locally present near the top of the unit and represent deposits of a channelized shelf-slope break. Abrupt sea level regression coupled with increased sedimentation rates due to tectonic unroofing in source areas in Idaho and Washington resulted in abrupt shallowing of sedimentation before deposition of the overlying Cowlitz Formation (C & W sandstone member). The C & W sandstone in cores from the Mist Gas Field and outcrops in the Rock Creek - Rocky Point area in Columbia County consists of massive to hummocky bedded sandstone with some bioturbated siltstone and coal formed in a delta front complex ranging from brackish-water swamps to storm-wave-dominated lower shoreface environments. Sandstone onlaps basement highs of Tillamook Volcanics (Nehalem arch), resulting in a complicated facies geometry with some intrabasinal basaltic detritus. Sedimentary structures, statistical grain size analysis, and lithofacies associations suggest that strong wave processes reworked the delta front sands during a transgression at the seaward edge of the system. Thickening-upward and shallowing-upward sequences record periods of westward deltaic progradation and increasing storm-wave energy. C & W gas reservoirs consist of well-sorted, friable, fine-grained arkose to lithic arkose. Sandstone reservoir porosity and permeability average 31% and 1200 md, respectively. Porosity is dominated by primary intergranular pores which have been reduced by (1) compaction of ductile grains, (2) formation of minor mixed-layer clay rim cement, sparry calcite cement and authigenic pyrite, and (3) late stage precipitation of plagioclase, K-feldspar, and quartz overgrowths. However, partial dissolution of plagiociase feldspar has created some secondary porosity. Although arkosic sandstones have high porosities and correspondingly high permeabilities, chioritic cement in volcaniclastic-rich sandstones significantly reduces permeability without concomitant reduction in porosity. The Cole Mountain basalt (informal) locally intnides and overlies the Cowlitz Formation. These basalts to basaltic andesites have calc-alkaline affinities and consist of hypabyssal sills, submarine lava flows, and local peperites which are lithologically, chemically, and petrographically distinct from the slightly older Tillamook Volcanics. The uppermost Narizian to Refugian (latest Eocene) Keasey Formation unconfonnably overlies the Cowlitz Formation in the study area. Volcanic and glauconitic sandstones at the base of the Keasey Formation mark the unconformity and reflect a period of slow sedimentation under slightly reducing conditions. The Keasey Formation predominantly consists of stractureless, tuffaceous fossiliferous mudstone deposited by hemipelagic sedimentation on the middle to upper slope. The informal Miocene (?) Ivy Creek formation locally disconformably overlies the Keasey Formation in the study area. The fluvially deposited Ivy Creek formation consists of a friable upper trough cross-bedded pebbly sand fades which overlies 9 m of blue organic-rich overbank clay. Local pebbly grits in matrix-support with buried flow-oriented rooted tree stems suggest that some debris flows entered the fluvial system from surrounding highlands. The unit may correspond to the middle Miocene Scappoose Formation. Northwest-trending down-to-the-northeast high-angle faults, some with oblique offset, and a subordinate set of older east-trending faults are the dominant structural features of the Rock Creek - Rocky Point area. The faulting produces a dissected structural high or upthrown basement block of middle to upper Eocene Tillamook Volcanics. Upper Eocene sedimentary units flank the north and south sides with occasional perched sedimentary outliers along the volcanic crest. Although source rock evaluations from this study indicate that the upper Eocene samples are thermally immature, it is possible that thermogenic thy gas at Mist migrated updip from more deeply buried Cowlitz shales and coals or equivalent Eocene strata in the adjacent Tualatin and Astoria basins. Close

• 536. [Article] An evaluation of planning for water quality control in the Willamette River Basin

  It is no longer possible in any area of the United States to formulate water resources plans for single purpose projects as has been done in past years. No longer can one of our greatest natural resources, water, ...

  Citation × Citation Citation Abstract Copy Title: An evaluation of planning for water quality control in the Willamette River Basin Author: Kirkpatrick, Kenton It is no longer possible in any area of the United States to formulate water resources plans for single purpose projects as has been done in past years. No longer can one of our greatest natural resources, water, be used solely for navigation, power generation, irrigation, or controlled for reducing floods. This resource must now serve a multitude of purposes in our society. Determining the present status of our water resources, what the future requirements will be, how to plan for these future needs, and implementation of these plans represents a major undertaking of local, State, and Federal authorities having interests in this field. In the Pacific Northwest, the Willamette Basin Task Force, acting under the auspices of the Columbia Basin Inter-Agency Committee, has been created to provide the coordinating mechanism for the prosecution of a comprehensive study for the management and development of the water and related land resources of the Willamette River Basin. This study is presently underway. In this thesis, information was collected from individuals associated with the Task Force, from minutes of meetings, and from other publications not readily available, to provide a single document giving the organization and objectives of the Task Force. The National comprehensive planning mechanism was studied to provide background information relating to the evolution of the Task Force and its operation. Water quality control is one of the areas of investigation of the Willamette Basin Task Force. It is directly related to and influenced by the several other multiple-purpose uses of the basin's water resources. It is this aspect of the comprehensive planning mechanism that has been considered in this thesis to evaluate what progress is being made in planning for present and future water quality control requirements for the basin. The results of this study indicate that additional study will be necessary, after further progress has been made by the Task Force, to fully evaluate the planning procedures and accomplishments of the Task Force. Conclusions indicate problems that have been encountered using this particular approach to water resources comprehensive planning. Various problems in the water pollution phase of the study are discussed. Several research study areas are suggested as a means of solving water quality problems which exist now in the Willamette River Basin and those water quality problems which are anticipated in the future as greater demands are placed on this resource. Title: An evaluation of planning for water quality control in the Willamette River Basin Author: Kirkpatrick, Kenton It is no longer possible in any area of the United States to formulate water resources plans for single purpose projects as has been done in past years. No longer can one of our greatest natural resources, water, be used solely for navigation, power generation, irrigation, or controlled for reducing floods. This resource must now serve a multitude of purposes in our society. Determining the present status of our water resources, what the future requirements will be, how to plan for these future needs, and implementation of these plans represents a major undertaking of local, State, and Federal authorities having interests in this field. In the Pacific Northwest, the Willamette Basin Task Force, acting under the auspices of the Columbia Basin Inter-Agency Committee, has been created to provide the coordinating mechanism for the prosecution of a comprehensive study for the management and development of the water and related land resources of the Willamette River Basin. This study is presently underway. In this thesis, information was collected from individuals associated with the Task Force, from minutes of meetings, and from other publications not readily available, to provide a single document giving the organization and objectives of the Task Force. The National comprehensive planning mechanism was studied to provide background information relating to the evolution of the Task Force and its operation. Water quality control is one of the areas of investigation of the Willamette Basin Task Force. It is directly related to and influenced by the several other multiple-purpose uses of the basin's water resources. It is this aspect of the comprehensive planning mechanism that has been considered in this thesis to evaluate what progress is being made in planning for present and future water quality control requirements for the basin. The results of this study indicate that additional study will be necessary, after further progress has been made by the Task Force, to fully evaluate the planning procedures and accomplishments of the Task Force. Conclusions indicate problems that have been encountered using this particular approach to water resources comprehensive planning. Various problems in the water pollution phase of the study are discussed. Several research study areas are suggested as a means of solving water quality problems which exist now in the Willamette River Basin and those water quality problems which are anticipated in the future as greater demands are placed on this resource. Close

• 537. [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

• 538. [Article] A statistical evaluation of the water quality impacts of Best Management Practices installed at Tillamook County dairies

  The overall goal of this study was to determine if the Tillamook Bay tributaries' water quality has improved as a result of the Best Management Practices (BMP) installed at Tillamook County Dairies. The ...

  Citation × Citation Citation Abstract Copy Title: A statistical evaluation of the water quality impacts of Best Management Practices installed at Tillamook County dairies Author: Dorsey-Kramer, Jadene The overall goal of this study was to determine if the Tillamook Bay tributaries' water quality has improved as a result of the Best Management Practices (BMP) installed at Tillamook County Dairies. The Rural Clean Water Program (RCWP) was a 10 to 15 year experiment designed to control agricultural non-point source (NPS) in rural watersheds throughout the nation. The RCWP Tillamook Watershed Project in Tillamook County, Oregon promoted the installation of manure management facilities and nutrient management strategies to improve the water quality of Tillamook Bay. The goal of the project was to reduce the fecal coliform concentration by 70%. Since the Bay is used for oyster production, there has been extensive sampling of Tillamook Bay and its tributaries since 1960. Unfortunately, much of the tributary data were compiled for a variety of short-term projects and therefore, the area lacks a consistent strategy for data collection. This inconsistency coupled with the variability in the data has made it difficult to evaluate changes in the water quality. It is important to note that this analysis is not a prediction model. It is a statistical model using an analysis of variance (ANOVA). The term, model, will be used to describe the response of ANOVA. This model is the best representation of the trend given the limited useful data that was available. The 33 year "tributary" analysis of the Wilson River station (D412130) determined fecal coliform concentration reductions as high as 69.83, 62.67, 69.02 and 72.38% in the Spring, Summer, Autumn and Winter, respectively. There were 48.59, 36.41, 47.21 and 52.95% reductions during the RCWP years (1980-1992) that may be attributed to the BMP's. The BMP installation began in 1981 and continued through 1995, however, the majority of the BMP's installation began in 1983. These reductions are not at optimum levels because of three important factors. First of all, not all farms have been provided with fullest possible array of manure containment facilities. Secondly, even with full implementation, some fecal coliform bacteria may escape. Finally, the BMP's must be diligently operated and maintained to provide the most effective capture and die-off of fecal coliform bacteria. When the BMP's are correctly installed and well managed, they will provide the maximum manure containment protection for the streams. Title: A statistical evaluation of the water quality impacts of Best Management Practices installed at Tillamook County dairies Author: Dorsey-Kramer, Jadene The overall goal of this study was to determine if the Tillamook Bay tributaries' water quality has improved as a result of the Best Management Practices (BMP) installed at Tillamook County Dairies. The Rural Clean Water Program (RCWP) was a 10 to 15 year experiment designed to control agricultural non-point source (NPS) in rural watersheds throughout the nation. The RCWP Tillamook Watershed Project in Tillamook County, Oregon promoted the installation of manure management facilities and nutrient management strategies to improve the water quality of Tillamook Bay. The goal of the project was to reduce the fecal coliform concentration by 70%. Since the Bay is used for oyster production, there has been extensive sampling of Tillamook Bay and its tributaries since 1960. Unfortunately, much of the tributary data were compiled for a variety of short-term projects and therefore, the area lacks a consistent strategy for data collection. This inconsistency coupled with the variability in the data has made it difficult to evaluate changes in the water quality. It is important to note that this analysis is not a prediction model. It is a statistical model using an analysis of variance (ANOVA). The term, model, will be used to describe the response of ANOVA. This model is the best representation of the trend given the limited useful data that was available. The 33 year "tributary" analysis of the Wilson River station (D412130) determined fecal coliform concentration reductions as high as 69.83, 62.67, 69.02 and 72.38% in the Spring, Summer, Autumn and Winter, respectively. There were 48.59, 36.41, 47.21 and 52.95% reductions during the RCWP years (1980-1992) that may be attributed to the BMP's. The BMP installation began in 1981 and continued through 1995, however, the majority of the BMP's installation began in 1983. These reductions are not at optimum levels because of three important factors. First of all, not all farms have been provided with fullest possible array of manure containment facilities. Secondly, even with full implementation, some fecal coliform bacteria may escape. Finally, the BMP's must be diligently operated and maintained to provide the most effective capture and die-off of fecal coliform bacteria. When the BMP's are correctly installed and well managed, they will provide the maximum manure containment protection for the streams. Close

• 539. [Article] The short term temporal and spatial variability of nitrogen and phosphorus in two Oregon Coast Range streams

  High intensity sampling was undertaken to characterize the temporal and spatial variability of oxidized nitrogen (NO3-N + NO2-N), ammonia-nitrogen (NH3-N), total dissolved phosphorus, total unfiltered ...

  Citation × Citation Citation Abstract Copy Title: The short term temporal and spatial variability of nitrogen and phosphorus in two Oregon Coast Range streams Author: Scherer, Robert A. High intensity sampling was undertaken to characterize the temporal and spatial variability of oxidized nitrogen (NO3-N + NO2-N), ammonia-nitrogen (NH3-N), total dissolved phosphorus, total unfiltered phosphorus and orthophosphorus (PO4-P) from two adjacent small streams in Western Oregon's Coast Range, Deer Creek (303 ha) and Flynn Creek (203 ha). Deer Creek has been 39 % clearcut from 1966 to 1987 while, Flynn Creek has never been logged and remains a "control" watershed for various research projects. A sequential wet-deposition precipitation sampler was also used to determine the temporal variability of oxidized-nitrogen, ammonia-nitrogen, total dissolved phosphorus and orthophosphorus entering a watershed during two storm events. Samples collected every one hour over a 25 to 26-h period during summer low flows indicated that oxidized nitrogen, ammonia-nitrogen, total unfiltered phosphorus, and orthophosphorus remained relatively constant. Total dissolved phosphorus concentrations were the most variable but did not have a discernible diel pattern. On a spatial scale, total unfiltered phosphorus and total dissolved phosphorus remained relatively constant or showed no discernable patterns when sampled over five 250-m intervals on each creek during summer low flow. Oxidized nitrogen and orthophosphorus concentrations increased on Deer Creek and decreased on Flynn Creek in an downstream direction. Ammonia-nitrogen concentrations decreased in a downstream direction on Deer Creek and remained constant on Flynn Creek. Nutrient constituent concentrations observed during high intensity sampling of three storm events had a variable response with stream discharge. Oxidized nitrogen concentration levels collected during the first fall storm appeared to be consistent with other research that has shown a flush of oxidized nitrogen out of the forest soil profile during the first fall storm. Sample concentrations from the first sampled storm had a 36 % decrease in concentration with the falling limb of the first sampled storm on both Deer Creek and Flynn Creek. Whereas, oxidized nitrogen concentrations had a 9 to 25 % decrease with an increase in discharge on the two studied creeks and returned to pre-storm levels with a decrease in discharge during two winter storms. Total unfiltered phosphorus concentrations had a 90 to 1150 % (0 to 10 fold) increase with a rise in storm discharge and decreased with the fall in storm discharge depending on the storm event and creek sampled. Ammonia-nitrogen, total dissolved phosphorus and orthophosphorus concentrations were not related to changes in discharge. Precipitation concentrations of oxidized nitrogen and ammonia-nitrogen either had a variable response or became diluted with an increase in rainfall amounts. The different responses appear to be related to storm intensity, with greater dilution in higher intensity storms. Results from this study indicate that the input and output of nitrogen and phosphorus into forested streams can be quite variable on both small temporal and spatial scales depending on the particular nutrient sampled, the particular creek sampled, stream flow conditions and season. It appears that sampling schemes designed for monitoring water chemistry or nutrient flux should initially presume significant short interval (2 to 20-h) variation until intensive sampling is able to prove otherwise. Title: The short term temporal and spatial variability of nitrogen and phosphorus in two Oregon Coast Range streams Author: Scherer, Robert A. High intensity sampling was undertaken to characterize the temporal and spatial variability of oxidized nitrogen (NO3-N + NO2-N), ammonia-nitrogen (NH3-N), total dissolved phosphorus, total unfiltered phosphorus and orthophosphorus (PO4-P) from two adjacent small streams in Western Oregon's Coast Range, Deer Creek (303 ha) and Flynn Creek (203 ha). Deer Creek has been 39 % clearcut from 1966 to 1987 while, Flynn Creek has never been logged and remains a "control" watershed for various research projects. A sequential wet-deposition precipitation sampler was also used to determine the temporal variability of oxidized-nitrogen, ammonia-nitrogen, total dissolved phosphorus and orthophosphorus entering a watershed during two storm events. Samples collected every one hour over a 25 to 26-h period during summer low flows indicated that oxidized nitrogen, ammonia-nitrogen, total unfiltered phosphorus, and orthophosphorus remained relatively constant. Total dissolved phosphorus concentrations were the most variable but did not have a discernible diel pattern. On a spatial scale, total unfiltered phosphorus and total dissolved phosphorus remained relatively constant or showed no discernable patterns when sampled over five 250-m intervals on each creek during summer low flow. Oxidized nitrogen and orthophosphorus concentrations increased on Deer Creek and decreased on Flynn Creek in an downstream direction. Ammonia-nitrogen concentrations decreased in a downstream direction on Deer Creek and remained constant on Flynn Creek. Nutrient constituent concentrations observed during high intensity sampling of three storm events had a variable response with stream discharge. Oxidized nitrogen concentration levels collected during the first fall storm appeared to be consistent with other research that has shown a flush of oxidized nitrogen out of the forest soil profile during the first fall storm. Sample concentrations from the first sampled storm had a 36 % decrease in concentration with the falling limb of the first sampled storm on both Deer Creek and Flynn Creek. Whereas, oxidized nitrogen concentrations had a 9 to 25 % decrease with an increase in discharge on the two studied creeks and returned to pre-storm levels with a decrease in discharge during two winter storms. Total unfiltered phosphorus concentrations had a 90 to 1150 % (0 to 10 fold) increase with a rise in storm discharge and decreased with the fall in storm discharge depending on the storm event and creek sampled. Ammonia-nitrogen, total dissolved phosphorus and orthophosphorus concentrations were not related to changes in discharge. Precipitation concentrations of oxidized nitrogen and ammonia-nitrogen either had a variable response or became diluted with an increase in rainfall amounts. The different responses appear to be related to storm intensity, with greater dilution in higher intensity storms. Results from this study indicate that the input and output of nitrogen and phosphorus into forested streams can be quite variable on both small temporal and spatial scales depending on the particular nutrient sampled, the particular creek sampled, stream flow conditions and season. It appears that sampling schemes designed for monitoring water chemistry or nutrient flux should initially presume significant short interval (2 to 20-h) variation until intensive sampling is able to prove otherwise. Close

• 540. [Article] Cumulative effects of land use on salmon habitat in southwest Oregon coastal streams

  As part of a hierarchical approach to classifying watersheds and stream habitats based on geomorphic and geologic criteria, we defined ten classes of fluvial and lacustrine habitats at the scale of valley ...

  Citation × Citation Citation Abstract Copy Title: Cumulative effects of land use on salmon habitat in southwest Oregon coastal streams Author: Frissell, Christopher Andrew, 1960- As part of a hierarchical approach to classifying watersheds and stream habitats based on geomorphic and geologic criteria, we defined ten classes of fluvial and lacustrine habitats at the scale of valley segments. Valley segments are landscape units which encompass surface waters and the adjacent floodplains and hillslopes with which they interact over time frames of thousands of years. They form a large-scale template that constrains the character of aquatic habitat, controls the effects of disturbances in riparian areas, and mediates responses of streams to upland and upstream events. The regional distribution of valley segment types in southwest Oregon reflects bedrock geology and tectonic history of the landscape. Fluvial segment types differ in stream adjacent landforms, slope erosion processes, floodplain and valley morphology, channel slope, riparian vegetation, streambank texture, gravel bar morphology, and pool-forming features. Studies that do not carefully account for inherent differences between valley segment types could fail to detect critical changes in stream habitat caused by human disturbance. Alluvial valley and alluviated canyon segment types, which have extensive floodplains, low channel slopes, abundant woody debris, and ample gravel beds, are of greatest direct importance for salmon and other native fishes. Virtually all alluvial valleys in the study area have been heavily disturbed by logging, agriculture, and residential development. Alluviated canyon segments located in the few drainage basins where human activity has been limited probably serve as habitat refugia for the last diverse assemblages and productive populations of salmon in the region. Alluviated canyons in extensively-fogged basins exhibit increased abundance of large woody debris, fewer cross-channel debris jams, more extensive bank erosion, reduced pool area and increased riffle area, shallower riffles, and increased surface concentration of fine sediments in pools and other habitats, compared to similar segments in lesser-disturbed basins. These changes in channel morphology and stability appear to be driven by increased sediment load, caused by logging-related landslides and other erosion sources. Field studies in Sixes River basin indicated that abundance and diversity of salmonid fishes declines as maximum stream temperature increases. Changes in summer distribution of juvenile chinook and coho salmon since 1970 are related to changes In water temperature. Although some tributaries have cooled, a decline in rearing distribution in mainstem areas could be caused by long-term loss of channel complexity and associated coolwater refugia. Analysis of fish habitat structures constructed by federal and state agencies indicated that failure rates are high. Recovery of anadromous fish runs in southwest Oregon will require protection of remaining habitat refugia and reduction of sediment yield from disturbed watersheds. Title: Cumulative effects of land use on salmon habitat in southwest Oregon coastal streams Author: Frissell, Christopher Andrew, 1960- As part of a hierarchical approach to classifying watersheds and stream habitats based on geomorphic and geologic criteria, we defined ten classes of fluvial and lacustrine habitats at the scale of valley segments. Valley segments are landscape units which encompass surface waters and the adjacent floodplains and hillslopes with which they interact over time frames of thousands of years. They form a large-scale template that constrains the character of aquatic habitat, controls the effects of disturbances in riparian areas, and mediates responses of streams to upland and upstream events. The regional distribution of valley segment types in southwest Oregon reflects bedrock geology and tectonic history of the landscape. Fluvial segment types differ in stream adjacent landforms, slope erosion processes, floodplain and valley morphology, channel slope, riparian vegetation, streambank texture, gravel bar morphology, and pool-forming features. Studies that do not carefully account for inherent differences between valley segment types could fail to detect critical changes in stream habitat caused by human disturbance. Alluvial valley and alluviated canyon segment types, which have extensive floodplains, low channel slopes, abundant woody debris, and ample gravel beds, are of greatest direct importance for salmon and other native fishes. Virtually all alluvial valleys in the study area have been heavily disturbed by logging, agriculture, and residential development. Alluviated canyon segments located in the few drainage basins where human activity has been limited probably serve as habitat refugia for the last diverse assemblages and productive populations of salmon in the region. Alluviated canyons in extensively-fogged basins exhibit increased abundance of large woody debris, fewer cross-channel debris jams, more extensive bank erosion, reduced pool area and increased riffle area, shallower riffles, and increased surface concentration of fine sediments in pools and other habitats, compared to similar segments in lesser-disturbed basins. These changes in channel morphology and stability appear to be driven by increased sediment load, caused by logging-related landslides and other erosion sources. Field studies in Sixes River basin indicated that abundance and diversity of salmonid fishes declines as maximum stream temperature increases. Changes in summer distribution of juvenile chinook and coho salmon since 1970 are related to changes In water temperature. Although some tributaries have cooled, a decline in rearing distribution in mainstem areas could be caused by long-term loss of channel complexity and associated coolwater refugia. Analysis of fish habitat structures constructed by federal and state agencies indicated that failure rates are high. Recovery of anadromous fish runs in southwest Oregon will require protection of remaining habitat refugia and reduction of sediment yield from disturbed watersheds. Close