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• 41. [Article] Soil moisture depletion trends under five plant species present on the Douglas-fir clear-cuts of Mary's Peak, Oregon

  Soil moisture depletion trends under five plant species growing on the clear-cuts of the Marys Peak Watershed near Corvallis, Oregon, were followed during the summers of 1963 and 1964. The species were ...

  Citation × Citation Citation Abstract Copy Title: Soil moisture depletion trends under five plant species present on the Douglas-fir clear-cuts of Mary's Peak, Oregon Author: Drew, Stephen Ernest Soil moisture depletion trends under five plant species growing on the clear-cuts of the Marys Peak Watershed near Corvallis, Oregon, were followed during the summers of 1963 and 1964. The species were Holcus lanatus, Lotus crassifolius var. subglaber, Gaultheria shallon, Berberis nervosa, and Acer circinatum; and were dominant plants of several stages in a successional sere occurring on the clear-cuts. Sampling of the moisture trends was limited to two clear-cut areas in order to reduce the variability due to location. On one area, Gaultheria, Berberis, and Lotus were growing in individual, pure stands. On the other, Acer was growing in closely grouped clumps and Holcus occupied the areas in between, The soil moisture was measured by an electrical resistance method. Plaster-of-paris blocks were installed at 6-, 12-, and 24-inch depths at nine locations in each species. The measurements were taken two or three times a week with an ohmmeter and expressed as an average in terms of atmospheres of tension for each day and depth. Supporting information on the precipitation, root distribution, and soils was also obtained. A root count for roots less than two millimeters in diameter was made from the face of a trench dug in each species. Soil descriptions made of the trench profiles, a particle size analysis, and 15 atmospheres determinations indicated that the soils of the two clear-cuts were similar. Each species had characteristic moisture depletion trends during the two years. Trends for Gaultheria indicated slow rates of moisture loss at all three depths and very little influence of precipitation. Gaultheria, an evergreen shrub, has thick, leathery leaves (characteristics which are generally associated with few stomata) and has a long period during which new stems emerge. The roots were concentrated near the surface just under the one and half to two inches of litter, and a few were growing inside large, dead roots of Douglas-fir. Depletion trends associated with Berberis were similar to Gaultheria except moisture losses at the 6-inch depth were more rapid. Berberis plants are also evergreen shrubs and have thick, leathery leaves but grow during a short period in the spring. Most of the roots developed in the top few inches of soil. Litter accumulation was slightly less (one to one and a half inches) and was not as uniformly distributed. Under Lotus, moisture trends at 6 and 12 inches fluctuated considerably. Depletion rates were rapid at all three depths. Lotus, a herbaceous species, grew quickly and flowered in the spring, then died back in mid-summer, evidently allowing increased infiltration of the rainfall. The rhizomes penetrated throughout the profile. Litter accumulation was about an inch, and the soil surface was somewhat rocky. Holcus trends at 6 and 12 inches showed an early and rapid moisture loss but a slightly delayed and slower loss at 24 inches. Holcus, a perennial bunch grass, also grew rapidly in the spring and then died back about mid-summer. Regrowth occurred following a substantial rainfall. The erect culms and dense mat of grass leaves (about two inches) surrounding the base of each plant created high air temperatures which may have caused high evapo-transpiration rates. Root concentration was greatest near the surface and decreased sharply with depth. Moisture losses under Acer were rapid at all three depths and very consistent without any fluctuations. Acer clumps grew during the spring and maintained their leaves throughout the summer. Such comparatively large plants (six to seven feet high) evidently had a high transpirational stress, and along with the one to two inches of litter, intercepted most of the precipitation. Root concentration decreased gradually with depth. This study provides a partial explanation for the replacement of Holcus by Lotus. It appears that Lotus is able to invade Holcus by producing rhizomes which grow underneath the dense root system of Holcus and utilize the moisture there. Lotus then increases in dominance by sending up shoots from the rhizomes. Possible explanations for the replacement of other species were not evident; however, there were some interesting correlations of the results with the sequence. With each advancing stage the depletion trends became more consistent. And, except for Lotus which had the smallest number of roots, the root count decreased with each advancing stage. The decrease was a reflection of an increase in the relative size of the roots. Results of this study are applicable to forest regeneration problems. In terms of influence upon soil moisture Acer stands would be very competitive with tree seedlings. Holcus and Lotus stands would also be competitive, Lotus perhaps more so at the deeper levels. Gaultheria and Berberís stands, on the other hand, would not be nearly as detrimental to tree seedling establishment. Title: Soil moisture depletion trends under five plant species present on the Douglas-fir clear-cuts of Mary's Peak, Oregon Author: Drew, Stephen Ernest Soil moisture depletion trends under five plant species growing on the clear-cuts of the Marys Peak Watershed near Corvallis, Oregon, were followed during the summers of 1963 and 1964. The species were Holcus lanatus, Lotus crassifolius var. subglaber, Gaultheria shallon, Berberis nervosa, and Acer circinatum; and were dominant plants of several stages in a successional sere occurring on the clear-cuts. Sampling of the moisture trends was limited to two clear-cut areas in order to reduce the variability due to location. On one area, Gaultheria, Berberis, and Lotus were growing in individual, pure stands. On the other, Acer was growing in closely grouped clumps and Holcus occupied the areas in between, The soil moisture was measured by an electrical resistance method. Plaster-of-paris blocks were installed at 6-, 12-, and 24-inch depths at nine locations in each species. The measurements were taken two or three times a week with an ohmmeter and expressed as an average in terms of atmospheres of tension for each day and depth. Supporting information on the precipitation, root distribution, and soils was also obtained. A root count for roots less than two millimeters in diameter was made from the face of a trench dug in each species. Soil descriptions made of the trench profiles, a particle size analysis, and 15 atmospheres determinations indicated that the soils of the two clear-cuts were similar. Each species had characteristic moisture depletion trends during the two years. Trends for Gaultheria indicated slow rates of moisture loss at all three depths and very little influence of precipitation. Gaultheria, an evergreen shrub, has thick, leathery leaves (characteristics which are generally associated with few stomata) and has a long period during which new stems emerge. The roots were concentrated near the surface just under the one and half to two inches of litter, and a few were growing inside large, dead roots of Douglas-fir. Depletion trends associated with Berberis were similar to Gaultheria except moisture losses at the 6-inch depth were more rapid. Berberis plants are also evergreen shrubs and have thick, leathery leaves but grow during a short period in the spring. Most of the roots developed in the top few inches of soil. Litter accumulation was slightly less (one to one and a half inches) and was not as uniformly distributed. Under Lotus, moisture trends at 6 and 12 inches fluctuated considerably. Depletion rates were rapid at all three depths. Lotus, a herbaceous species, grew quickly and flowered in the spring, then died back in mid-summer, evidently allowing increased infiltration of the rainfall. The rhizomes penetrated throughout the profile. Litter accumulation was about an inch, and the soil surface was somewhat rocky. Holcus trends at 6 and 12 inches showed an early and rapid moisture loss but a slightly delayed and slower loss at 24 inches. Holcus, a perennial bunch grass, also grew rapidly in the spring and then died back about mid-summer. Regrowth occurred following a substantial rainfall. The erect culms and dense mat of grass leaves (about two inches) surrounding the base of each plant created high air temperatures which may have caused high evapo-transpiration rates. Root concentration was greatest near the surface and decreased sharply with depth. Moisture losses under Acer were rapid at all three depths and very consistent without any fluctuations. Acer clumps grew during the spring and maintained their leaves throughout the summer. Such comparatively large plants (six to seven feet high) evidently had a high transpirational stress, and along with the one to two inches of litter, intercepted most of the precipitation. Root concentration decreased gradually with depth. This study provides a partial explanation for the replacement of Holcus by Lotus. It appears that Lotus is able to invade Holcus by producing rhizomes which grow underneath the dense root system of Holcus and utilize the moisture there. Lotus then increases in dominance by sending up shoots from the rhizomes. Possible explanations for the replacement of other species were not evident; however, there were some interesting correlations of the results with the sequence. With each advancing stage the depletion trends became more consistent. And, except for Lotus which had the smallest number of roots, the root count decreased with each advancing stage. The decrease was a reflection of an increase in the relative size of the roots. Results of this study are applicable to forest regeneration problems. In terms of influence upon soil moisture Acer stands would be very competitive with tree seedlings. Holcus and Lotus stands would also be competitive, Lotus perhaps more so at the deeper levels. Gaultheria and Berberís stands, on the other hand, would not be nearly as detrimental to tree seedling establishment. Close

• 42. [Article] The future of open access and library publishing

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Emerald Group Publishing Limited and can be found at: http://www.emeraldgrouppu...

  Citation × Citation Citation Abstract Copy Title: The future of open access and library publishing This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Emerald Group Publishing Limited and can be found at: http://www.emeraldgrouppublishing.com/products/journals/journals.htm?id=nlw. Title: The future of open access and library publishing This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Emerald Group Publishing Limited and can be found at: http://www.emeraldgrouppublishing.com/products/journals/journals.htm?id=nlw. Close

• 43. [Article] The long term effects of burning on plant succession

  The succession of plants over a period of 25 years was analyzed on clearcut areas in the western Cascades of Washington and Oregon. Thirty-three paired burned and unburned plots were reexamined in 1975. ...

  Citation × Citation Citation Abstract Copy Title: The long term effects of burning on plant succession Author: Kraemer, James Fred The succession of plants over a period of 25 years was analyzed on clearcut areas in the western Cascades of Washington and Oregon. Thirty-three paired burned and unburned plots were reexamined in 1975. Data were combined with records from prior examinations by Morris (1970). Cover trends of six major brush species and five major herbaceous species were studied. Long term differences in plant succession between burned and unburned sites were identified. Total brush and herbaceous cover trends were similar on burned and unburned sites. Total herbaceous cover peaked approximately 14 years following logging and declined rapidly in subsequent years. Total brush cover steadily increased during the 25 year period. Increases in total brush cover were most rapid during the initial 14 years following logging. Ceanothus velutinus cover and occurrence was greater on burned plots while Rhododendron macrophylluni, Acer circinatum, and Gaultheria shallon had greater cover and occurrence on unburned plots. Greater cover of residual species on unburned sites was an important factor accounting for differences in successional trends. Variability between different plot pairs limited analyses which could be made. Results indicated secondary succession in the western Cascades varies greatly with elevation and between geographic localities. Title: The long term effects of burning on plant succession Author: Kraemer, James Fred The succession of plants over a period of 25 years was analyzed on clearcut areas in the western Cascades of Washington and Oregon. Thirty-three paired burned and unburned plots were reexamined in 1975. Data were combined with records from prior examinations by Morris (1970). Cover trends of six major brush species and five major herbaceous species were studied. Long term differences in plant succession between burned and unburned sites were identified. Total brush and herbaceous cover trends were similar on burned and unburned sites. Total herbaceous cover peaked approximately 14 years following logging and declined rapidly in subsequent years. Total brush cover steadily increased during the 25 year period. Increases in total brush cover were most rapid during the initial 14 years following logging. Ceanothus velutinus cover and occurrence was greater on burned plots while Rhododendron macrophylluni, Acer circinatum, and Gaultheria shallon had greater cover and occurrence on unburned plots. Greater cover of residual species on unburned sites was an important factor accounting for differences in successional trends. Variability between different plot pairs limited analyses which could be made. Results indicated secondary succession in the western Cascades varies greatly with elevation and between geographic localities. Close

• 44. [Article] Vegnet regional pest monitoring: Research report to the Agricultural Research Foundation, 2005

  Part 1: Bean mold project: What is an effective alternative to Ronilan for control of gray and white mold in snap beans when mold pressure is severe? When can we use a less expensive single fungicide ...

  Citation × Citation Citation Abstract Copy Title: Vegnet regional pest monitoring: Research report to the Agricultural Research Foundation, 2005 Author: McGrath, Daniel Part 1: Bean mold project: What is an effective alternative to Ronilan for control of gray and white mold in snap beans when mold pressure is severe? When can we use a less expensive single fungicide application without putting the bean crop at significant risk? Part 2: 12 Spot Beetle Project: By tracking the regional population trends for the twelve spot beetle, we can reduce field scouting. Regional population trends tell a grower or agricultural professional when it pays to sweep and reduces risk of a no spray decision. Part 3: Regional Pest Monitoring: Pest monitoring stations were established and maintained on farms in the major vegetable production regions of the Willamette Valley. Pest population trends were communicated to growers and agricultural professionals by fax and email as needed Title: Vegnet regional pest monitoring: Research report to the Agricultural Research Foundation, 2005 Author: McGrath, Daniel Part 1: Bean mold project: What is an effective alternative to Ronilan for control of gray and white mold in snap beans when mold pressure is severe? When can we use a less expensive single fungicide application without putting the bean crop at significant risk? Part 2: 12 Spot Beetle Project: By tracking the regional population trends for the twelve spot beetle, we can reduce field scouting. Regional population trends tell a grower or agricultural professional when it pays to sweep and reduces risk of a no spray decision. Part 3: Regional Pest Monitoring: Pest monitoring stations were established and maintained on farms in the major vegetable production regions of the Willamette Valley. Pest population trends were communicated to growers and agricultural professionals by fax and email as needed Close

• 45. [Article] Scenarios as Radical Alternatives: The Case of Aquaculture in the Finnish Archipelago Sea

  The method of constructing scenarios is neither straightforward nor unproblematic. We propose first of all the term epistemic closure for representing the necessary methodological limitations of scenario ...

  Citation × Citation Citation Abstract Copy Title: Scenarios as Radical Alternatives: The Case of Aquaculture in the Finnish Archipelago Sea Author: Hukkinen, Janne, Brunn, Henrik, Eklund, Erland Year: 2001 The method of constructing scenarios is neither straightforward nor unproblematic. We propose first of all the term epistemic closure for representing the necessary methodological limitations of scenario construction. Whenever a particular kind of epistemic closure becomes a habit within some field of scenario-making, we use the term conventional scenarios. The problem with conventional scenario-making is that its analysis of the future is restricted – it can only register the events and trends that its particular approach allows it to see. There is a risk of highly contingent developments, for which there is no preparation in society. Therefore, we want to emphasize the importance of constructing unconventional scenarios, that is, scenarios that are not based on conventional epistemic closure. Our second argument concerns the wide range of variance in future development. Social evolution includes events and developmental trajectories that are impossible to discern with any approach that represents development in a linear fashion. Most scenarios consider the past to be a model for the future, in which existing trends are projected into the future. We call these scenarios trend-based. Other scenarios – called Event-based scenarios – acknowledge that the future is contingent in relation to our knowledge, and focus more on the fact that the pattern of change can change. To illustrate our methodological arguments, a small case study on the future of aquaculture in the archipelago of southwestern Finland is included in the text. Title: Scenarios as Radical Alternatives: The Case of Aquaculture in the Finnish Archipelago Sea Author: Hukkinen, Janne, Brunn, Henrik, Eklund, Erland Year: 2001 The method of constructing scenarios is neither straightforward nor unproblematic. We propose first of all the term epistemic closure for representing the necessary methodological limitations of scenario construction. Whenever a particular kind of epistemic closure becomes a habit within some field of scenario-making, we use the term conventional scenarios. The problem with conventional scenario-making is that its analysis of the future is restricted – it can only register the events and trends that its particular approach allows it to see. There is a risk of highly contingent developments, for which there is no preparation in society. Therefore, we want to emphasize the importance of constructing unconventional scenarios, that is, scenarios that are not based on conventional epistemic closure. Our second argument concerns the wide range of variance in future development. Social evolution includes events and developmental trajectories that are impossible to discern with any approach that represents development in a linear fashion. Most scenarios consider the past to be a model for the future, in which existing trends are projected into the future. We call these scenarios trend-based. Other scenarios – called Event-based scenarios – acknowledge that the future is contingent in relation to our knowledge, and focus more on the fact that the pattern of change can change. To illustrate our methodological arguments, a small case study on the future of aquaculture in the archipelago of southwestern Finland is included in the text. Close

• 46. [Article] Trends in key economic and social indicators for Pacific Northwest states and counties

  Local (Country) variations in key social and economic indicators are important in Oregon and Washington. Covered employment, wage and salary, unemployment, and population data for 1987 through 1997 showed ...

  Citation × Citation Citation Abstract Copy Title: Trends in key economic and social indicators for Pacific Northwest states and counties Author: Pacific Northwest Research Station (Portland, Or.), Raettig, Terry L. Local (Country) variations in key social and economic indicators are important in Oregon and Washington. Covered employment, wage and salary, unemployment, and population data for 1987 through 1997 showed regional trends in these indicators, which are compared with national trends. Future updates will be published in the 'Production, Prices, Employment, and Trade in Northwest Forest Industries' series from the Pacific Northwest Research Station. Title: Trends in key economic and social indicators for Pacific Northwest states and counties Author: Pacific Northwest Research Station (Portland, Or.), Raettig, Terry L. Local (Country) variations in key social and economic indicators are important in Oregon and Washington. Covered employment, wage and salary, unemployment, and population data for 1987 through 1997 showed regional trends in these indicators, which are compared with national trends. Future updates will be published in the 'Production, Prices, Employment, and Trade in Northwest Forest Industries' series from the Pacific Northwest Research Station. Close

• 47. [Article] Some factors influencing the trends of salmon populations in Oregon

  Three factors were found to be significantly correlated with the fluctuations and trends in silver salmon production in Oregon. Logging was found to adversely affect the runs of salmon in later years. ...

  Citation × Citation Citation Abstract Copy Title: Some factors influencing the trends of salmon populations in Oregon Author: Johnson, Donald R., Oregon. Fish Commission, Hodges, John I., McKernan, Donald L. (Donald Lynn), 1918-1979 Three factors were found to be significantly correlated with the fluctuations and trends in silver salmon production in Oregon. Logging was found to adversely affect the runs of salmon in later years. Exceptional winter floods seem to produce poor resulting runs. Low summer water flows also appear to produce lower than average runs on some rivers, while higher summer flows appear to be followed by an increase in the resultant runs. The intensity of fishing was also found to affect the subsequent productivity of the fisheries. Increases in fishing effort on the rivers studied were followed in succeeding cycles by a lower catch, and when the fishing effort declined the ensuing production of silver salmon generally increased. Other factors studied did not bear a significant relationship to the fluctuations or trends of productivity of silver salmon. Title: Some factors influencing the trends of salmon populations in Oregon Author: Johnson, Donald R., Oregon. Fish Commission, Hodges, John I., McKernan, Donald L. (Donald Lynn), 1918-1979 Three factors were found to be significantly correlated with the fluctuations and trends in silver salmon production in Oregon. Logging was found to adversely affect the runs of salmon in later years. Exceptional winter floods seem to produce poor resulting runs. Low summer water flows also appear to produce lower than average runs on some rivers, while higher summer flows appear to be followed by an increase in the resultant runs. The intensity of fishing was also found to affect the subsequent productivity of the fisheries. Increases in fishing effort on the rivers studied were followed in succeeding cycles by a lower catch, and when the fishing effort declined the ensuing production of silver salmon generally increased. Other factors studied did not bear a significant relationship to the fluctuations or trends of productivity of silver salmon. Close

• 48. [Article] Trends in Developed Land Cover Adjacent to Habitat for Threatened Salmon in Puget Sound, Washington, U.S.A.

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

  Citation × Citation Citation Abstract Copy Title: Trends in Developed Land Cover Adjacent to Habitat for Threatened Salmon in Puget Sound, Washington, U.S.A. Author: Ford, Michael J., et al., Kennedy, Robert E., Beechie, Timothy J., Bartz, Krista K. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Title: Trends in Developed Land Cover Adjacent to Habitat for Threatened Salmon in Puget Sound, Washington, U.S.A. Author: Ford, Michael J., et al., Kennedy, Robert E., Beechie, Timothy J., Bartz, Krista K. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Close

• 49. [Article] Smoking Trends and Disparities Among Black and Non-Hispanic Whites in California

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Author(s) and published by Oxford University Press on behalf of the Society ...

  Citation × Citation Citation Abstract Copy Title: Smoking Trends and Disparities Among Black and Non-Hispanic Whites in California Author: Sakuma, Kari-Lyn Kobayakawa, Trinidad, Dennis R., Gruder, Charles L., Fagan, Pebbles, Blanco, Lyzette, Cappelli, Christopher, Felicitas, Jamie This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Author(s) and published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. It can be found at: http://ntr.oxfordjournals.org/ Title: Smoking Trends and Disparities Among Black and Non-Hispanic Whites in California Author: Sakuma, Kari-Lyn Kobayakawa, Trinidad, Dennis R., Gruder, Charles L., Fagan, Pebbles, Blanco, Lyzette, Cappelli, Christopher, Felicitas, Jamie This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Author(s) and published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. It can be found at: http://ntr.oxfordjournals.org/ Close

• 50. [Article] Coupling snowpack and groundwater dynamics to interpret historical streamflow trends in the western United States

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http:...

  Citation × Citation Citation Abstract Copy Title: Coupling snowpack and groundwater dynamics to interpret historical streamflow trends in the western United States Author: Lewis, Sarah L., Safeeq, Mohammad, Tague, Christina. L., Grant, Gordon E. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http://onlinelibrary.wiley.com/. Title: Coupling snowpack and groundwater dynamics to interpret historical streamflow trends in the western United States Author: Lewis, Sarah L., Safeeq, Mohammad, Tague, Christina. L., Grant, Gordon E. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http://onlinelibrary.wiley.com/. Close