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• 141. [Article] Spatial and temporal patterns of windthrow in the Bull Run Watershed, Oregon

  Throughout the 20th century, windthrow has affected forests in the Bull Run watershed, a 26,500 ha basin that is the principal water source for the city of Portland, Oregon. Windthrow from storms in 1973 ...

  Citation × Citation Citation Abstract Copy Title: Spatial and temporal patterns of windthrow in the Bull Run Watershed, Oregon Author: Sinton, Diana Stuart Throughout the 20th century, windthrow has affected forests in the Bull Run watershed, a 26,500 ha basin that is the principal water source for the city of Portland, Oregon. Windthrow from storms in 1973 and 1983 was mapped into a geographic information system (GIS) and compared to a 1931 windthrow pattern that had been determined through field work and photo interpretation. By relating the windthrow patterns to vegetation, topography, soils, and edges created by forest canopy openings such as lakes and clearcuts, the degree to which these factors influence the patterns was tested with a logistic regression. Distanced sampling was used to compensate for spatial autocorrelation among the data. The results showed that topographic exposure most strongly affected the 1931 windthrow patterns, while a greater number of 1973 and 1983 windthrow patches were associated with clearcut edges than other edges, and those edges were more likely to be affected when located on shallow soils with a high hazard for windthrow. All three storms were characterized by northeasterly winds, a common occurrence during winter months in the vicinity of the Columbia River Gorge. However, the particular combination of at least two-consecutive days of severe east winds, and sub-freezing temperatures, had only occurred four times between 1948 and 1994, including both the 1973 and 1983 windthrow events. Multiple approaches were taken to estimate future windthrow risk in the Bull Run that incorporated both spatial and temporal variables. Probabilistic windthrow maps showing zones of low, medium, and high risk were generated for current forest conditions, as well as conditions projected-to the years 2010 and 2075. Because variables such as vegetation height and clearcut edges are ephemeral, the prediction of future risk incorporates assumptions of vegetation succession. However, a mean return interval calculated for predicted windthrow-generating storms suggests that such events could occur as frequently as once every three years. While no model can predict the precise location of a disturbance as variable as windthrow, an understanding of the relative spatial and temporal probability of windthrow provides useful information for forest planners and managers. Title: Spatial and temporal patterns of windthrow in the Bull Run Watershed, Oregon Author: Sinton, Diana Stuart Throughout the 20th century, windthrow has affected forests in the Bull Run watershed, a 26,500 ha basin that is the principal water source for the city of Portland, Oregon. Windthrow from storms in 1973 and 1983 was mapped into a geographic information system (GIS) and compared to a 1931 windthrow pattern that had been determined through field work and photo interpretation. By relating the windthrow patterns to vegetation, topography, soils, and edges created by forest canopy openings such as lakes and clearcuts, the degree to which these factors influence the patterns was tested with a logistic regression. Distanced sampling was used to compensate for spatial autocorrelation among the data. The results showed that topographic exposure most strongly affected the 1931 windthrow patterns, while a greater number of 1973 and 1983 windthrow patches were associated with clearcut edges than other edges, and those edges were more likely to be affected when located on shallow soils with a high hazard for windthrow. All three storms were characterized by northeasterly winds, a common occurrence during winter months in the vicinity of the Columbia River Gorge. However, the particular combination of at least two-consecutive days of severe east winds, and sub-freezing temperatures, had only occurred four times between 1948 and 1994, including both the 1973 and 1983 windthrow events. Multiple approaches were taken to estimate future windthrow risk in the Bull Run that incorporated both spatial and temporal variables. Probabilistic windthrow maps showing zones of low, medium, and high risk were generated for current forest conditions, as well as conditions projected-to the years 2010 and 2075. Because variables such as vegetation height and clearcut edges are ephemeral, the prediction of future risk incorporates assumptions of vegetation succession. However, a mean return interval calculated for predicted windthrow-generating storms suggests that such events could occur as frequently as once every three years. While no model can predict the precise location of a disturbance as variable as windthrow, an understanding of the relative spatial and temporal probability of windthrow provides useful information for forest planners and managers. Close

• 142. [Article] The effects of light on photosynthesis and rooting of leafy cuttings of Pisum sativum L.

  The effects of light incident on leafy cuttings is quite complex because' light influences several factors which may affect root formation. One effect of light is to influence the carbohydrate status of ...

  Citation × Citation Citation Abstract Copy Title: The effects of light on photosynthesis and rooting of leafy cuttings of Pisum sativum L. Author: Davis, Tim D. The effects of light incident on leafy cuttings is quite complex because' light influences several factors which may affect root formation. One effect of light is to influence the carbohydrate status of the cutting by influencing photosynthesis. The role of current photosynthate in the rooting of leafy cuttings is uncertain. Accordingly I investigated the extent to which the supply of current photosynthate influences root formation on leafy cuttings of Pisum sativum L. When net photosynthesis was reduced to zero by maintaining the cuttings at the C0₂ compensation point or by blocking CO₂ exchange with an antitranspirant, rooting was reduced to about 50% of the controls. In addition to reducing rooting these treatments significantly reduced sucrose and glucose levels in the basal portion of the cuttings compared to controls. These experiments suggest that the supply of current photo- synthate can limit root formation. The above conclusions were supported by experiments using different photosynthetic photon flux densities and photoperiod lengths during rooting. Defoliation experiments also supported the role of current photosynthate in root formation. Defoliation of cuttings reduced rooting and carbohydrate levels in the base of the cuttings. Light incident on defoliated stems increased rooting and sucrose levels in the base of the stems. Dipping the defoliated cuttings in an antitranspirant blocked CO₂ fixation and almost completely inhibited root formation. These data suggest that stem photosynthesis also contributed to root formation. These experiments suggest that one of the major effects of light incident on leafy pea cuttings is to influence the amount of photosynthate available for root formation. It is difficult to establish whether current photosynthate influences rooting directly or indirectly by affecting some other factor(s) which control rooting. Whatever the case, treatments which influence photosynthesis influence rooting in a parallel manner. Title: The effects of light on photosynthesis and rooting of leafy cuttings of Pisum sativum L. Author: Davis, Tim D. The effects of light incident on leafy cuttings is quite complex because' light influences several factors which may affect root formation. One effect of light is to influence the carbohydrate status of the cutting by influencing photosynthesis. The role of current photosynthate in the rooting of leafy cuttings is uncertain. Accordingly I investigated the extent to which the supply of current photosynthate influences root formation on leafy cuttings of Pisum sativum L. When net photosynthesis was reduced to zero by maintaining the cuttings at the C0₂ compensation point or by blocking CO₂ exchange with an antitranspirant, rooting was reduced to about 50% of the controls. In addition to reducing rooting these treatments significantly reduced sucrose and glucose levels in the basal portion of the cuttings compared to controls. These experiments suggest that the supply of current photo- synthate can limit root formation. The above conclusions were supported by experiments using different photosynthetic photon flux densities and photoperiod lengths during rooting. Defoliation experiments also supported the role of current photosynthate in root formation. Defoliation of cuttings reduced rooting and carbohydrate levels in the base of the cuttings. Light incident on defoliated stems increased rooting and sucrose levels in the base of the stems. Dipping the defoliated cuttings in an antitranspirant blocked CO₂ fixation and almost completely inhibited root formation. These data suggest that stem photosynthesis also contributed to root formation. These experiments suggest that one of the major effects of light incident on leafy pea cuttings is to influence the amount of photosynthate available for root formation. It is difficult to establish whether current photosynthate influences rooting directly or indirectly by affecting some other factor(s) which control rooting. Whatever the case, treatments which influence photosynthesis influence rooting in a parallel manner. Close

• 143. [Article] Funneled flow mechanisms in a sloping layered soil: Laboratory investigation

  This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/.

  Citation × Citation Citation Abstract Copy Title: Funneled flow mechanisms in a sloping layered soil: Laboratory investigation Author: Braddock, R. D., Selker, J. S., Steenhuis, T. S., Parlange, J.-Y., Kim, J.-S., Boll, J., Walter, M. T., Heilig, A. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Title: Funneled flow mechanisms in a sloping layered soil: Laboratory investigation Author: Braddock, R. D., Selker, J. S., Steenhuis, T. S., Parlange, J.-Y., Kim, J.-S., Boll, J., Walter, M. T., Heilig, A. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Close

• 144. [Article] Optical and EPR investigations of the photochemistry of KCl:OH

  The hydroxide ion as a substitutional defect in KC1 can be photo-dissociated at liquid nitrogen temperature by ultraviolet light. The photochemistry of this system was investigated by EPR and optical absorption methods. ...

  Citation × Citation Citation Abstract Copy Title: Optical and EPR investigations of the photochemistry of KCl:OH Author: Bowen, Robert Clifford The hydroxide ion as a substitutional defect in KC1 can be photo-dissociated at liquid nitrogen temperature by ultraviolet light. The photochemistry of this system was investigated by EPR and optical absorption methods. Theoretical calculations were also performed in an investigation of the KC1:OH system. The bleaching behavior of photochemically colored KC1:OH was studied by simultaneous visible and EPR spectroscopy, and by broad range optical spectroscopy in the range from 185 nm to 2000 nm. The behavior of the system on warming from liquid nitrogen temperature to room temperature was also studied by the same methods. Pure KC1 crystals were colored with x- or gamma-rays at room temperature and studied by EPR and optical methods. The bleaching rate of photochemically colored KC1:OH was determined to be equivalent when measured by EPR or optical data. This result contradicted data reported previously. The disappearance of the EPR spectrum of ultraviolet irradiated KC1:OH at 250 K was correlated with optical data. This showed that the disappearance of the EPR was simultaneous with the conversion of H₂O⁻ centers to F centers. Results were presented and arguments given that the products and mechanism of the bleaching of H₂0⁻ centers were analagous to the products and mechanism of bleaching F centers. Approximate quantum mechanical calculations were performed which indicated that an exchange interaction of the unpaired F and 0⁻ electrons was not responsible for the disappearance of the EPR spectrum. Suggestions were made for further investigations which may yield information on the system. Title: Optical and EPR investigations of the photochemistry of KCl:OH Author: Bowen, Robert Clifford The hydroxide ion as a substitutional defect in KC1 can be photo-dissociated at liquid nitrogen temperature by ultraviolet light. The photochemistry of this system was investigated by EPR and optical absorption methods. Theoretical calculations were also performed in an investigation of the KC1:OH system. The bleaching behavior of photochemically colored KC1:OH was studied by simultaneous visible and EPR spectroscopy, and by broad range optical spectroscopy in the range from 185 nm to 2000 nm. The behavior of the system on warming from liquid nitrogen temperature to room temperature was also studied by the same methods. Pure KC1 crystals were colored with x- or gamma-rays at room temperature and studied by EPR and optical methods. The bleaching rate of photochemically colored KC1:OH was determined to be equivalent when measured by EPR or optical data. This result contradicted data reported previously. The disappearance of the EPR spectrum of ultraviolet irradiated KC1:OH at 250 K was correlated with optical data. This showed that the disappearance of the EPR was simultaneous with the conversion of H₂O⁻ centers to F centers. Results were presented and arguments given that the products and mechanism of the bleaching of H₂0⁻ centers were analagous to the products and mechanism of bleaching F centers. Approximate quantum mechanical calculations were performed which indicated that an exchange interaction of the unpaired F and 0⁻ electrons was not responsible for the disappearance of the EPR spectrum. Suggestions were made for further investigations which may yield information on the system. Close

• 145. [Article] Seasonal and altitudinal regulation of embryonic and nymphal development in Allonemobius fasciatus (Orthoptera:Gryllidae)

  The physiological adaptations involved in the seasonal and altitudinal regulation of the life cycle in Allonemobius fasciatus were studied. This species maintains a univoltine life cycle with an embryonic diapause ...

  Citation × Citation Citation Abstract Copy Title: Seasonal and altitudinal regulation of embryonic and nymphal development in Allonemobius fasciatus (Orthoptera:Gryllidae) Author: Tanaka, Seiji The physiological adaptations involved in the seasonal and altitudinal regulation of the life cycle in Allonemobius fasciatus were studied. This species maintains a univoltine life cycle with an embryonic diapause over an altitudinal gradient of as large as 1,000 m. A more than 1.5 -month difference exists in hatching time between the highest and lowest altitudes studied. Little or no difference was detected among populations from different altitudes when various developmental traits such as diapause intensity, postdiapause development, and nymphal development, were compared in the laboratory. The photo periodic regulation of nymphal development seems to play an important role in compensating for the shorter growing season at higher elevations. The embryo of A. fasciatus showed seasonal variation in diapause characteristics. Diapause intensity measured as the duration of the egg stage at 20°C was greater in eggs laid early in the season than in those laid later. At 20°C, all embryos entered "winter diapause" at the end of the appendage-formation stage. However, when incubated at higher temperatures, another type of diapause was manifested before that stage. The higher the temperature the earlier was the stage at which this developmental suppression (called "summer diapause") was imposed. The induction of summer diapause depended not only upon the temperature of incubation but also upon the time of ovi-position. The capability of entering summer diapause at a high tem perature was decreased as the time of oviposition was delayed. The effects of temperature and moisture on embryonic development were examined using eggs with or without summer diapause and it is suggested that the role of summer diapause is not to ensure the survival of eggs under dry, warm conditions in summer but to avoid untimely hatching before winter, and to stabilize the univoltine life cycle in this species. Non-diapause development was induced when eggs were transferred from 20 to 27°C in early embryonic stages, although they entered diapause when constantly held at either of these temperatures. Based on this and other results, a model for the possible mechanism underlying the control of induction and intensity of diapause was proposed. Title: Seasonal and altitudinal regulation of embryonic and nymphal development in Allonemobius fasciatus (Orthoptera:Gryllidae) Author: Tanaka, Seiji The physiological adaptations involved in the seasonal and altitudinal regulation of the life cycle in Allonemobius fasciatus were studied. This species maintains a univoltine life cycle with an embryonic diapause over an altitudinal gradient of as large as 1,000 m. A more than 1.5 -month difference exists in hatching time between the highest and lowest altitudes studied. Little or no difference was detected among populations from different altitudes when various developmental traits such as diapause intensity, postdiapause development, and nymphal development, were compared in the laboratory. The photo periodic regulation of nymphal development seems to play an important role in compensating for the shorter growing season at higher elevations. The embryo of A. fasciatus showed seasonal variation in diapause characteristics. Diapause intensity measured as the duration of the egg stage at 20°C was greater in eggs laid early in the season than in those laid later. At 20°C, all embryos entered "winter diapause" at the end of the appendage-formation stage. However, when incubated at higher temperatures, another type of diapause was manifested before that stage. The higher the temperature the earlier was the stage at which this developmental suppression (called "summer diapause") was imposed. The induction of summer diapause depended not only upon the temperature of incubation but also upon the time of ovi-position. The capability of entering summer diapause at a high tem perature was decreased as the time of oviposition was delayed. The effects of temperature and moisture on embryonic development were examined using eggs with or without summer diapause and it is suggested that the role of summer diapause is not to ensure the survival of eggs under dry, warm conditions in summer but to avoid untimely hatching before winter, and to stabilize the univoltine life cycle in this species. Non-diapause development was induced when eggs were transferred from 20 to 27°C in early embryonic stages, although they entered diapause when constantly held at either of these temperatures. Based on this and other results, a model for the possible mechanism underlying the control of induction and intensity of diapause was proposed. Close

• 146. [Article] A spatial analysis of factors influencing farmland conversion in the Bangkok metropolitan area, Thailand

  Agricultural land conversion is a complex process that involves a matrix of decisions and decision-makers. This study examines the nature and relative significance of spatial factors that influence the decisions ...

  Citation × Citation Citation Abstract Copy Title: A spatial analysis of factors influencing farmland conversion in the Bangkok metropolitan area, Thailand Author: Nathalang, Santita Agricultural land conversion is a complex process that involves a matrix of decisions and decision-makers. This study examines the nature and relative significance of spatial factors that influence the decisions of farmers who either sell farmland to developers for urban use or retain it for agricultural use. The conceptual model views farmers as boundedly rational individuals who seek satisfying economic and noneconomic returns from land. Their decisions are influenced by urban-generated factors that reflect land demand, by agricultural factors that determine the economic viability of agriculture under urban influences as well as by the decision-makers' characteristics. The study is done within the political and socioeconomic context of Bangkok, Thailand. The Thonburi region of the Bangkok Metropolitan Area is chosen as an example of a land use transition zone experiencing various urbanization pressures. Aerial photography is used to establish the location and magnitude of agricultural to urban land conversion between 1967 and 1983. Data from land use maps constructed from the air photo base maps and data from the Agricultural Census are used to test the research hypotheses of the study. The two primary research questions are: 1) Are the farmers' decisions to hold or to sell land related to urbanization pressures, economic viability of agriculture and farmers' characteristics?; and 2) What is the relative significance of these factors in influencing land conversion? Bivariate correlation and multiple regression analyses reveal the significant relationships of farmland conversion and the following variables: accessibility of land parcels, level of agricultural investment, age, education and occupational status. The dominant explanatory variables are the proximity to community centers and major roads. Secondary to them are the roles of farmers' age, education level and investment in irrigation. The effects of the other decision-maker's characteristics and agricultural variables are marginal but statistically significant. The study provides insight into the roles of agricultural viability as well as urban demand factors and decision-maker's characteristics in influencing the pace of land conversion in the developing country. Title: A spatial analysis of factors influencing farmland conversion in the Bangkok metropolitan area, Thailand Author: Nathalang, Santita Agricultural land conversion is a complex process that involves a matrix of decisions and decision-makers. This study examines the nature and relative significance of spatial factors that influence the decisions of farmers who either sell farmland to developers for urban use or retain it for agricultural use. The conceptual model views farmers as boundedly rational individuals who seek satisfying economic and noneconomic returns from land. Their decisions are influenced by urban-generated factors that reflect land demand, by agricultural factors that determine the economic viability of agriculture under urban influences as well as by the decision-makers' characteristics. The study is done within the political and socioeconomic context of Bangkok, Thailand. The Thonburi region of the Bangkok Metropolitan Area is chosen as an example of a land use transition zone experiencing various urbanization pressures. Aerial photography is used to establish the location and magnitude of agricultural to urban land conversion between 1967 and 1983. Data from land use maps constructed from the air photo base maps and data from the Agricultural Census are used to test the research hypotheses of the study. The two primary research questions are: 1) Are the farmers' decisions to hold or to sell land related to urbanization pressures, economic viability of agriculture and farmers' characteristics?; and 2) What is the relative significance of these factors in influencing land conversion? Bivariate correlation and multiple regression analyses reveal the significant relationships of farmland conversion and the following variables: accessibility of land parcels, level of agricultural investment, age, education and occupational status. The dominant explanatory variables are the proximity to community centers and major roads. Secondary to them are the roles of farmers' age, education level and investment in irrigation. The effects of the other decision-maker's characteristics and agricultural variables are marginal but statistically significant. The study provides insight into the roles of agricultural viability as well as urban demand factors and decision-maker's characteristics in influencing the pace of land conversion in the developing country. Close

• 147. [Article] Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape

  Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors ...

  Citation × Citation Citation Abstract Copy Title: Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape Author: Schweickert, Tina K. Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors of change become increasingly useful. This study considers competing schools of interpretation about human impacts on ecological landscapes and develops a case study of one thirty-six square mile township in Oregon’s Waldo Hills. Built on evidence from 1851 surveyor notes, maps, journals, aerial photos, interviews, and contemporary environmental and ecological data, this study demonstrates a transformation from ecologically diverse ecosystems under the management of native peoples to ecologically depressed monoculture landscapes under industrialized agriculture. This thesis argues that the fundamental beliefs of human societies (i.e., worldviews) become expressed in the landscape. The nature-as-community view of the Kalapuya Indians resulted in a complex, curvilinear mosaic of prairie, savanna, and woodland. The individualized and rationalized view of the Euroamericans resulted in a simplified landscape of squared-off fields, channelized streams, and roads aligned to the survey grid. Thomas Jefferson’s rectangular survey, built on the ‘virtuous square’, is examined as a symbolic and tangible instrument of rapid expansion and exploitation across the American West. Understanding that worldviews become expressed in physical conditions may benefit those working to create sustainable futures; i.e., long-term and widespread ecological improvements will likely succeed only if society at large shares a fundamental belief in the value of healthy ecosystems. Title: Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape Author: Schweickert, Tina K. Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors of change become increasingly useful. This study considers competing schools of interpretation about human impacts on ecological landscapes and develops a case study of one thirty-six square mile township in Oregon’s Waldo Hills. Built on evidence from 1851 surveyor notes, maps, journals, aerial photos, interviews, and contemporary environmental and ecological data, this study demonstrates a transformation from ecologically diverse ecosystems under the management of native peoples to ecologically depressed monoculture landscapes under industrialized agriculture. This thesis argues that the fundamental beliefs of human societies (i.e., worldviews) become expressed in the landscape. The nature-as-community view of the Kalapuya Indians resulted in a complex, curvilinear mosaic of prairie, savanna, and woodland. The individualized and rationalized view of the Euroamericans resulted in a simplified landscape of squared-off fields, channelized streams, and roads aligned to the survey grid. Thomas Jefferson’s rectangular survey, built on the ‘virtuous square’, is examined as a symbolic and tangible instrument of rapid expansion and exploitation across the American West. Understanding that worldviews become expressed in physical conditions may benefit those working to create sustainable futures; i.e., long-term and widespread ecological improvements will likely succeed only if society at large shares a fundamental belief in the value of healthy ecosystems. Close

• 148. [Article] A demonstration for hazard rating susceptibility of stands to Douglas-fir tussock moth defoliation on the Palouse Ranger District, 1. Probability of defoliatio

  A practical demonstration of a method for rating forest stands as to their probability of defoliation by the Douglas-fir tussock moth using aerial photographs and available cruise data was done in the ...

  Citation × Citation Citation Abstract Copy Title: A demonstration for hazard rating susceptibility of stands to Douglas-fir tussock moth defoliation on the Palouse Ranger District, 1. Probability of defoliatio Author: Heller, Robert C., Hard, John S., Kessler, Bruce L., United States. Forest Service. Northern Region. State & Private Forestry A practical demonstration of a method for rating forest stands as to their probability of defoliation by the Douglas-fir tussock moth using aerial photographs and available cruise data was done in the Palouse Ranger District, Clearwater National Forest, Idaho. A nonlinear computer program, RISK, was used to identify significant independent variables for the prediction of probability of defoliation (dependent variable). A hazard rating model developed in the Blue Mountains of Oregon and Washington was localized for the Palouse District using data collected from previously established plots. Data for the Palouse RD hazard rating were obtained from Stand Examination and Management Status Records, aerial photos, topographic maps, and Orthophoto Quadrangles. Four final hazard rating models were developed using various combinations of the following independent variables: elevation, slope, cosine of the aspect times the tangent of the slope, sine of the aspect times the tangent of the slope, topographic position, stand level, stand density, presence of volcanic ash in the soil, stand age, and percent host species. Hazard ratings which indicate the probabilities of a stand being defoliated during a tussock moth outbreak ware computed for 496 forest stands, and stands were color-coded on a map by probability of defoliation classes. Title: A demonstration for hazard rating susceptibility of stands to Douglas-fir tussock moth defoliation on the Palouse Ranger District, 1. Probability of defoliatio Author: Heller, Robert C., Hard, John S., Kessler, Bruce L., United States. Forest Service. Northern Region. State & Private Forestry A practical demonstration of a method for rating forest stands as to their probability of defoliation by the Douglas-fir tussock moth using aerial photographs and available cruise data was done in the Palouse Ranger District, Clearwater National Forest, Idaho. A nonlinear computer program, RISK, was used to identify significant independent variables for the prediction of probability of defoliation (dependent variable). A hazard rating model developed in the Blue Mountains of Oregon and Washington was localized for the Palouse District using data collected from previously established plots. Data for the Palouse RD hazard rating were obtained from Stand Examination and Management Status Records, aerial photos, topographic maps, and Orthophoto Quadrangles. Four final hazard rating models were developed using various combinations of the following independent variables: elevation, slope, cosine of the aspect times the tangent of the slope, sine of the aspect times the tangent of the slope, topographic position, stand level, stand density, presence of volcanic ash in the soil, stand age, and percent host species. Hazard ratings which indicate the probabilities of a stand being defoliated during a tussock moth outbreak ware computed for 496 forest stands, and stands were color-coded on a map by probability of defoliation classes. Close

• 149. [Article] STEM Learning in the Library Learning Commons: Examining Whiteboards for Evidence of Learning Through Student-Generated Visualizations

  Presentation at the American Library Association Annual Conference, ACRL STS Research Forum, June 29, 2014, Las Vegas, Nevada. Libraries are currently challenged to design dynamic learning spaces that ...

  Citation × Citation Citation Abstract Copy Title: STEM Learning in the Library Learning Commons: Examining Whiteboards for Evidence of Learning Through Student-Generated Visualizations Author: Hussong-Christian, Uta, Stoddart, Richard A. Presentation at the American Library Association Annual Conference, ACRL STS Research Forum, June 29, 2014, Las Vegas, Nevada. Libraries are currently challenged to design dynamic learning spaces that are attractive to students and support them in various forms of learning. STEM students, in particular, need spaces that allow them to engage in visualization activities, which ongoing research shows is a vital component of STEM learning. Working from the hypothesis that whiteboards in library learning commons support learning through visualization, librarians at Oregon State University’s The Valley Library undertook an exploratory, photo-ethnographic study to determine the types of visualization activities in which students engage. Librarians captured student-generated whiteboard content over the course of one term by photographing whiteboards in the learning commons twice each week for 10 weeks. These photographs are currently being analyzed for the types of visualization they contain. Researcher definitions range widely but visualizations, such as study notes [on whiteboards], may include direct representations, diagrams, matrices, charts, trees, tables, graphs, pyramids, causal chains, timelines, or even outlines (Cifuentes and Hsieh, 2004). One early finding is that STEM content is much more heavily represented in the visualizations than is social sciences or humanities content. This study contributes to the increasing body of qualitative assessment data on learning commons but makes a unique contribution by attempting to directly connect library spaces to specific educational activities that impact student learning. The results of this study can be used to identify and convey the types of high impact learning activities that libraries support and will inform the thoughtful design of library learning spaces for STEM and other students. Title: STEM Learning in the Library Learning Commons: Examining Whiteboards for Evidence of Learning Through Student-Generated Visualizations Author: Hussong-Christian, Uta, Stoddart, Richard A. Presentation at the American Library Association Annual Conference, ACRL STS Research Forum, June 29, 2014, Las Vegas, Nevada. Libraries are currently challenged to design dynamic learning spaces that are attractive to students and support them in various forms of learning. STEM students, in particular, need spaces that allow them to engage in visualization activities, which ongoing research shows is a vital component of STEM learning. Working from the hypothesis that whiteboards in library learning commons support learning through visualization, librarians at Oregon State University’s The Valley Library undertook an exploratory, photo-ethnographic study to determine the types of visualization activities in which students engage. Librarians captured student-generated whiteboard content over the course of one term by photographing whiteboards in the learning commons twice each week for 10 weeks. These photographs are currently being analyzed for the types of visualization they contain. Researcher definitions range widely but visualizations, such as study notes [on whiteboards], may include direct representations, diagrams, matrices, charts, trees, tables, graphs, pyramids, causal chains, timelines, or even outlines (Cifuentes and Hsieh, 2004). One early finding is that STEM content is much more heavily represented in the visualizations than is social sciences or humanities content. This study contributes to the increasing body of qualitative assessment data on learning commons but makes a unique contribution by attempting to directly connect library spaces to specific educational activities that impact student learning. The results of this study can be used to identify and convey the types of high impact learning activities that libraries support and will inform the thoughtful design of library learning spaces for STEM and other students. Close

• 150. [Article] The Impact of Crystal Morphology on the Opto-Electronic Properties of Amorphous and Organic Crystalline Materials

  Organic aggregates and transparent amorphous metals are transforming opto-electronic devices such as highly efficiency solar cells and flexible displays. We present a fundamental optical study of how local ...

  Citation × Citation Citation Abstract Copy Title: The Impact of Crystal Morphology on the Opto-Electronic Properties of Amorphous and Organic Crystalline Materials Author: Brandt, Gregory, Mirek Organic aggregates and transparent amorphous metals are transforming opto-electronic devices such as highly efficiency solar cells and flexible displays. We present a fundamental optical study of how local morphology critically impacts the device performance of both stacked, conjugated organics and In-Ga-Zn-O (IGZO) transparent metallic materials. Derivatives of anthradithiophene (ADT): ADTTES-F, ADT-TDMS-F, and ADT-TSBS-F were investigated through polarization-dependent optical absorption spectroscopy. While each ADT derivative has a different intermolecular stacking morphology, the intramolecular physics is dominated by their identical conjugated ring structure. We show that the morphology-dependent dipole-moment orientation drastically changes the electronic excited states, through mapping the absorption spectra anisotropy with respect to polarization. Photocells ideally need transparent metals to efficiently harvest the charges created. We present a method of extracting the band gap and Fermi energies for amorphous metals and semiconductors. To determine the Fermi energy and defect bands in such materials we developed a novel simulation code to fit data obtained from a spectroscopic technique called Photo Excited Charge Collection Spectroscopy (PECCS).We applied this technique to amorphous In-Ga-Zn-O (IGZO) transistors, however due to IP protection, we present the procedure through analysis on a simulated device. When applied to a real IGZO device, the code gave realistic values (on the order of eV) for the Fermi energy and optical band gap (Within 0.2 eV). Title: The Impact of Crystal Morphology on the Opto-Electronic Properties of Amorphous and Organic Crystalline Materials Author: Brandt, Gregory, Mirek Organic aggregates and transparent amorphous metals are transforming opto-electronic devices such as highly efficiency solar cells and flexible displays. We present a fundamental optical study of how local morphology critically impacts the device performance of both stacked, conjugated organics and In-Ga-Zn-O (IGZO) transparent metallic materials. Derivatives of anthradithiophene (ADT): ADTTES-F, ADT-TDMS-F, and ADT-TSBS-F were investigated through polarization-dependent optical absorption spectroscopy. While each ADT derivative has a different intermolecular stacking morphology, the intramolecular physics is dominated by their identical conjugated ring structure. We show that the morphology-dependent dipole-moment orientation drastically changes the electronic excited states, through mapping the absorption spectra anisotropy with respect to polarization. Photocells ideally need transparent metals to efficiently harvest the charges created. We present a method of extracting the band gap and Fermi energies for amorphous metals and semiconductors. To determine the Fermi energy and defect bands in such materials we developed a novel simulation code to fit data obtained from a spectroscopic technique called Photo Excited Charge Collection Spectroscopy (PECCS).We applied this technique to amorphous In-Ga-Zn-O (IGZO) transistors, however due to IP protection, we present the procedure through analysis on a simulated device. When applied to a real IGZO device, the code gave realistic values (on the order of eV) for the Fermi energy and optical band gap (Within 0.2 eV). Close