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• 721. [Article] Epiphytic macrolichens in relation to forest management and topography in a western Oregon watershed

  This dissertation describes patterns in epiphytic macrolichen community composition, diversity, and biomass across various stand types in the Blue River watershed of western Oregon. It first examines the ...

  Citation × Citation Citation Abstract Copy Title: Epiphytic macrolichens in relation to forest management and topography in a western Oregon watershed Author: Berryman, Shanti D. This dissertation describes patterns in epiphytic macrolichen community composition, diversity, and biomass across various stand types in the Blue River watershed of western Oregon. It first examines the relative importance of ecological factors such as stand age, remnant tree retention, and topography to lichen communities in the landscape. It then develops models for estimating epiphytic macrolichen biomass and uses these models to assess potential impacts of forest management strategies on future lichen biomass in the watershed. Epiphytic macrolichen communities were sampled in 117 coniferous stands in uplands and riparian areas. Stands were typed by stand age (young, <20; pole, 21-80; mature, 81-200; and old-growth, >200 yrs) and by the degree of remnant tree retention (older trees that survived the most recent disturbance). Lichen biomass (oven-dried, kg/ha) was estimated for three functional groups: nitrogen-fixing cyanolichens, forage lichens, and matrix lichens in 63 of the 117 stands. Elevation was the leading factor related to differences in macrolichen communities and biomass. Cyanolichens (dominated by Lobaria oregana) were largely limited to lower elevations and were most abundant in old growth (median 1,377 kg/ha). Lichen community composition changed with stand age. Remnant presence was related only to lichen community differences in young stands. Lichen biomass increased with stand age and with remnant retention. Stands along perennial streams were cyanolichen hotspots compared to uplands. Lichen biomass was unrelated to uplands and riparian areas. Regression models estimating lichen biomass by functional group were developed from topography, stand structure, and lichen communities. The model for cyanolichen biomass had the strongest predictive power (R²= 0.85), whereas models for forage and matrix lichen biomass were less powerful (R² = 0.55 and R² = 0.58, respectively). We estimated cyanolichen and forage lichen biomass in the present watershed and forecasted lichen biomass in 200 yrs for two different management scenarios: the Landscape Plan (LP) and the Northwest Forest Plan (NWFP). Under both scenarios, lichen biomass was predicted to increase substantially from current levels due to increased remnant tree retention and the elimination of clear-cutting. The LP scenario yielded 12% higher forage lichen biomass and 8% higher cyanolichen biomass than the NWFP. Title: Epiphytic macrolichens in relation to forest management and topography in a western Oregon watershed Author: Berryman, Shanti D. This dissertation describes patterns in epiphytic macrolichen community composition, diversity, and biomass across various stand types in the Blue River watershed of western Oregon. It first examines the relative importance of ecological factors such as stand age, remnant tree retention, and topography to lichen communities in the landscape. It then develops models for estimating epiphytic macrolichen biomass and uses these models to assess potential impacts of forest management strategies on future lichen biomass in the watershed. Epiphytic macrolichen communities were sampled in 117 coniferous stands in uplands and riparian areas. Stands were typed by stand age (young, <20; pole, 21-80; mature, 81-200; and old-growth, >200 yrs) and by the degree of remnant tree retention (older trees that survived the most recent disturbance). Lichen biomass (oven-dried, kg/ha) was estimated for three functional groups: nitrogen-fixing cyanolichens, forage lichens, and matrix lichens in 63 of the 117 stands. Elevation was the leading factor related to differences in macrolichen communities and biomass. Cyanolichens (dominated by Lobaria oregana) were largely limited to lower elevations and were most abundant in old growth (median 1,377 kg/ha). Lichen community composition changed with stand age. Remnant presence was related only to lichen community differences in young stands. Lichen biomass increased with stand age and with remnant retention. Stands along perennial streams were cyanolichen hotspots compared to uplands. Lichen biomass was unrelated to uplands and riparian areas. Regression models estimating lichen biomass by functional group were developed from topography, stand structure, and lichen communities. The model for cyanolichen biomass had the strongest predictive power (R²= 0.85), whereas models for forage and matrix lichen biomass were less powerful (R² = 0.55 and R² = 0.58, respectively). We estimated cyanolichen and forage lichen biomass in the present watershed and forecasted lichen biomass in 200 yrs for two different management scenarios: the Landscape Plan (LP) and the Northwest Forest Plan (NWFP). Under both scenarios, lichen biomass was predicted to increase substantially from current levels due to increased remnant tree retention and the elimination of clear-cutting. The LP scenario yielded 12% higher forage lichen biomass and 8% higher cyanolichen biomass than the NWFP. Close

• 722. [Article] Values, assumptions, and actions in an administrative team : a symbolic analysis of the expression of culture in one community college setting

  Organizational culture is broadly recognized as a significant force in organizational action. Since the phenomenon of culture has real impact on organizations, our understanding of that impact is vital ...

  Citation × Citation Citation Abstract Copy Title: Values, assumptions, and actions in an administrative team : a symbolic analysis of the expression of culture in one community college setting Author: Goulard, Elizabeth Ann Organizational culture is broadly recognized as a significant force in organizational action. Since the phenomenon of culture has real impact on organizations, our understanding of that impact is vital to organizational health. While academic settings provide a rich environment for studying culture, relatively little research on culture has occurred in this setting. This interpretive study contributes to our understanding of the administrative subculture in higher education by examining cultural influences at work within a community college administrative team. The framework of organizational symbolism influenced the overall research goal of interpreting cultural themes found in a community college administrative team and exploring how these themes were expressed in organizational action. Organizational culture was conceptualized as having three levels of manifestation: symbols of culture, organizational values, and basic assumptions about reality. Research questions were developed with the aim of examining each of these cultural levels within the executive administrative team at Northwest Community College and addressing the belief that administrative team actions and decisions are an expression of the common values and assumptions held by team members. This study integrated field observation with interviews and document review to uncover the values, assumptions, and actions of administrative team members. Cultural windows used to focus observations and interviews included (a) organizational stories, (b) organizational heroes, (c) organizational symbols, and (d) organizational traditions. The following cultural themes were evident within the executive administrative team at Northwest Community College: community, change and innovation, fairness, candor, hard work, learning and development, humor, teamwork, delegation and shared decision-making, and customer responsiveness and recognition of others. These themes were expressed in numerous team actions. Symbols reinforcing each cultural theme were active within the organization. These symbols included artifacts, traditions, and prominent actions taken by the team. The executive administrative team's primary role within the organization was to influence organizational decisions and modify organizational involvement regarding decision-making. Key historical figures or events appear to have played a role in developing some cultural themes through strengthening existing values or creating new, contrasting values. Paradoxical value sets were found within three cultural themes: hard work (balancing workload), teamwork (separateness), and delegation and shared decision-making (direct involvement). Title: Values, assumptions, and actions in an administrative team : a symbolic analysis of the expression of culture in one community college setting Author: Goulard, Elizabeth Ann Organizational culture is broadly recognized as a significant force in organizational action. Since the phenomenon of culture has real impact on organizations, our understanding of that impact is vital to organizational health. While academic settings provide a rich environment for studying culture, relatively little research on culture has occurred in this setting. This interpretive study contributes to our understanding of the administrative subculture in higher education by examining cultural influences at work within a community college administrative team. The framework of organizational symbolism influenced the overall research goal of interpreting cultural themes found in a community college administrative team and exploring how these themes were expressed in organizational action. Organizational culture was conceptualized as having three levels of manifestation: symbols of culture, organizational values, and basic assumptions about reality. Research questions were developed with the aim of examining each of these cultural levels within the executive administrative team at Northwest Community College and addressing the belief that administrative team actions and decisions are an expression of the common values and assumptions held by team members. This study integrated field observation with interviews and document review to uncover the values, assumptions, and actions of administrative team members. Cultural windows used to focus observations and interviews included (a) organizational stories, (b) organizational heroes, (c) organizational symbols, and (d) organizational traditions. The following cultural themes were evident within the executive administrative team at Northwest Community College: community, change and innovation, fairness, candor, hard work, learning and development, humor, teamwork, delegation and shared decision-making, and customer responsiveness and recognition of others. These themes were expressed in numerous team actions. Symbols reinforcing each cultural theme were active within the organization. These symbols included artifacts, traditions, and prominent actions taken by the team. The executive administrative team's primary role within the organization was to influence organizational decisions and modify organizational involvement regarding decision-making. Key historical figures or events appear to have played a role in developing some cultural themes through strengthening existing values or creating new, contrasting values. Paradoxical value sets were found within three cultural themes: hard work (balancing workload), teamwork (separateness), and delegation and shared decision-making (direct involvement). Close

• 723. [Article] Evaluating the relative roles of positive and negative interactions in communities : shade, herbivory and physiological stress in the rocky intertidal zone

  Evaluating the relative influences of positive and negative interactions in shaping communities is a major topic in modern ecology. Facilitative interactions between basal species are important in habitats ...

  Citation × Citation Citation Abstract Copy Title: Evaluating the relative roles of positive and negative interactions in communities : shade, herbivory and physiological stress in the rocky intertidal zone Author: Burnaford, Jennifer L. Evaluating the relative influences of positive and negative interactions in shaping communities is a major topic in modern ecology. Facilitative interactions between basal species are important in habitats with intense predation pressure or severe abiotic stresses. However, few studies address the potential for positive interactions between trophic levels to influence community structure by altering patterns of predation. I investigated whether the association between the canopy-forming alga Hedophyllum sessile and the herbivorous chiton Katharine tunicata was due to the provision of a refuge from predation, a preference for Hedophyllum as a food item, or amelioration of abiotic conditions. In a field experiment, Katharine were not affected by predation or Hedophyllum thalli, but showed a strong behavioral selection for shaded areas during summertime low tides. By providing shade, Hedophyllum controls the distribution of the system's major herbivore. In a second field experiment I evaluated the relative effects of shade and Katharina on the rest of the community. Shade had strong positive effects on a suite of consumers, increasing abundances of seven animal groups relative to unshaded areas. Shade and Katharina had quantitatively equal negative effects on the abundance of basal species, but their effects were qualitatively very different. The positive interaction between Hedophyllum and Katharina affects the entire community by altering patterns of herbivory. Such complex networks of positive, negative, direct and indirect interactions can produce deceptively simple patterns in natural systems. I used field experiments and laboratory analyses to evaluate potential physiological benefits of this positive interaction on Katharina. Levels of heat shock protein 70 isoforms in field populations were greater in summer than in winter, suggesting that Katharina are experiencing seasonal sub-lethal stress. Although shade did not affect Hsp7O levels in Katharina maintained in field enclosures, amelioration of abiotic stresses through positive biotic interactions could have direct physiological consequences for beneficiary species. These studies provide strong evidence that positive interactions between trophic levels can profoundly affect the physiology of individuals, the distribution and abundance of populations, and the structure of communities. I present a conceptual model to summarize predictions of the importance of these multi-level positive interactions in structuring communities. Title: Evaluating the relative roles of positive and negative interactions in communities : shade, herbivory and physiological stress in the rocky intertidal zone Author: Burnaford, Jennifer L. Evaluating the relative influences of positive and negative interactions in shaping communities is a major topic in modern ecology. Facilitative interactions between basal species are important in habitats with intense predation pressure or severe abiotic stresses. However, few studies address the potential for positive interactions between trophic levels to influence community structure by altering patterns of predation. I investigated whether the association between the canopy-forming alga Hedophyllum sessile and the herbivorous chiton Katharine tunicata was due to the provision of a refuge from predation, a preference for Hedophyllum as a food item, or amelioration of abiotic conditions. In a field experiment, Katharine were not affected by predation or Hedophyllum thalli, but showed a strong behavioral selection for shaded areas during summertime low tides. By providing shade, Hedophyllum controls the distribution of the system's major herbivore. In a second field experiment I evaluated the relative effects of shade and Katharina on the rest of the community. Shade had strong positive effects on a suite of consumers, increasing abundances of seven animal groups relative to unshaded areas. Shade and Katharina had quantitatively equal negative effects on the abundance of basal species, but their effects were qualitatively very different. The positive interaction between Hedophyllum and Katharina affects the entire community by altering patterns of herbivory. Such complex networks of positive, negative, direct and indirect interactions can produce deceptively simple patterns in natural systems. I used field experiments and laboratory analyses to evaluate potential physiological benefits of this positive interaction on Katharina. Levels of heat shock protein 70 isoforms in field populations were greater in summer than in winter, suggesting that Katharina are experiencing seasonal sub-lethal stress. Although shade did not affect Hsp7O levels in Katharina maintained in field enclosures, amelioration of abiotic stresses through positive biotic interactions could have direct physiological consequences for beneficiary species. These studies provide strong evidence that positive interactions between trophic levels can profoundly affect the physiology of individuals, the distribution and abundance of populations, and the structure of communities. I present a conceptual model to summarize predictions of the importance of these multi-level positive interactions in structuring communities. Close

• 724. [Article] Negative effect of purple loosestrife and reed canary grass on the diversity of wetland plant and moth communities

  Invasive plants have the potential to reduce the diversity of species in plant and animal communities. I examined the negative effect of two invasive wetland plants, purple loosestrife and reed canary ...

  Citation × Citation Citation Abstract Copy Title: Negative effect of purple loosestrife and reed canary grass on the diversity of wetland plant and moth communities Author: Schooler, Shon Invasive plants have the potential to reduce the diversity of species in plant and animal communities. I examined the negative effect of two invasive wetland plants, purple loosestrife and reed canary grass, on the species richness and diversity of plant and moth communities within 24 wetland study sites in the Pacific Northwest. I hypothesized that as the cover of the invasive species increased, the diversity of the local plant and moth community would decrease. Increasing cover of purple loosestrife and reed canary grass was associated with reduction in the diversity of wetland plant communities irrespective of the diversity measure examined. Moth species richness was positively correlated with plant species richness, but I found no detectable direct negative association between loosestrife and canary grass cover and moth community diversity. Wetland hydrology, soil characteristics, and topography were measured to control for potentially covarying and confounding influences on plant diversity. Temperature, ambient light, and surrounding land-use were measured to control for potentially covarying and confounding influences on moth sampling and diversity. None of these variables was significantly associated with invasive species abundance. This strengthens the conclusion that the invasive species are the cause of the decline in biotic diversity. Understanding the mechanisms that influence plant invasions will lead to more effective management strategies. I examined the role of soil nutrients in the invasive potential of purple loosestrife. I hypothesized that nitrogen was the primary nutrient limiting plant growth and that higher soil nitrogen concentrations would increase the growth of purple loosestrife within 13 wetland sites in the Willamette Valley, Oregon. Using greenhouse experiments and field studies I found that nitrogen was the primary resource limiting both plant community biomass and purple loosestrife growth. Purple loosestrife grew well in soils taken from nine wetlands currently not colonized by loosestrife. Given their similar hydroperiods, this suggests that these wetlands will be susceptible to invasion should loosestrife colonize. Plant species richness was negatively associated with soil nitrate and ammonium concentrations, This trend included invaded and non-invaded sites. Therefore, to prevent repeated invasions, management strategies should consider methods for reducing soil nutrient concentrations, particularly nitrogen. Title: Negative effect of purple loosestrife and reed canary grass on the diversity of wetland plant and moth communities Author: Schooler, Shon Invasive plants have the potential to reduce the diversity of species in plant and animal communities. I examined the negative effect of two invasive wetland plants, purple loosestrife and reed canary grass, on the species richness and diversity of plant and moth communities within 24 wetland study sites in the Pacific Northwest. I hypothesized that as the cover of the invasive species increased, the diversity of the local plant and moth community would decrease. Increasing cover of purple loosestrife and reed canary grass was associated with reduction in the diversity of wetland plant communities irrespective of the diversity measure examined. Moth species richness was positively correlated with plant species richness, but I found no detectable direct negative association between loosestrife and canary grass cover and moth community diversity. Wetland hydrology, soil characteristics, and topography were measured to control for potentially covarying and confounding influences on plant diversity. Temperature, ambient light, and surrounding land-use were measured to control for potentially covarying and confounding influences on moth sampling and diversity. None of these variables was significantly associated with invasive species abundance. This strengthens the conclusion that the invasive species are the cause of the decline in biotic diversity. Understanding the mechanisms that influence plant invasions will lead to more effective management strategies. I examined the role of soil nutrients in the invasive potential of purple loosestrife. I hypothesized that nitrogen was the primary nutrient limiting plant growth and that higher soil nitrogen concentrations would increase the growth of purple loosestrife within 13 wetland sites in the Willamette Valley, Oregon. Using greenhouse experiments and field studies I found that nitrogen was the primary resource limiting both plant community biomass and purple loosestrife growth. Purple loosestrife grew well in soils taken from nine wetlands currently not colonized by loosestrife. Given their similar hydroperiods, this suggests that these wetlands will be susceptible to invasion should loosestrife colonize. Plant species richness was negatively associated with soil nitrate and ammonium concentrations, This trend included invaded and non-invaded sites. Therefore, to prevent repeated invasions, management strategies should consider methods for reducing soil nutrient concentrations, particularly nitrogen. Close

• 725. [Article] The experiences of older students' use of web-based student services

  The purpose of this phenomenological case study was to understand the experiences of older students' use of web-based student services in a community college setting. For the purpose of this study the ...

  Citation × Citation Citation Abstract Copy Title: The experiences of older students' use of web-based student services Author: Ho, Katy W. The purpose of this phenomenological case study was to understand the experiences of older students' use of web-based student services in a community college setting. For the purpose of this study the term "older student" was defined as people born between the years 1943 and 1960. This group of people, often described as the Baby Boomer generation, would not have had access to computer technologies had they gone to college during their adolescent years. Web-based student services was defined as the range of student services which are placed online, allowing students to access information and services without needing to see someone in-person. There were three major reasons for this study: (a) the increase in the development and use of online student services, (b) the increase of older students in higher education, and (c) further need to understand the unique experiences of older students in higher education. The case study design used an interpretive social science philosophical approach. The study was conducted at a large multi-campus community college in a metropolitan area located in the Northwest. A combination of survey, interviews, institutional data, and student-journals were used to answer the following research questions: (a) What is the experience of older students with web-based technology in a community college setting, (b) How do the older students' overall experiences and use of web-based services affect their community college experience, and (c) How might older students' background and experiences with web-based student services inform community college policy and practice? Close examination of data revealed several major themes of older students' experiences with online student services. These themes are: • Student Assumptions • Self-Motivation • Influence of Prior Work Experiences • User Preferences • How and What Online Services are Used • User Suggestions When these themes are taken into consideration with related literature on the digital divide, technology use in student affairs, older student experiences in the community college, and older students' use of technology, this study offers implications for community college leaders and practitioners in the student affairs and technology development. The implications of this study may impact online service development, assessment of computer literacy, program enhancement or development, and technical changes. Title: The experiences of older students' use of web-based student services Author: Ho, Katy W. The purpose of this phenomenological case study was to understand the experiences of older students' use of web-based student services in a community college setting. For the purpose of this study the term "older student" was defined as people born between the years 1943 and 1960. This group of people, often described as the Baby Boomer generation, would not have had access to computer technologies had they gone to college during their adolescent years. Web-based student services was defined as the range of student services which are placed online, allowing students to access information and services without needing to see someone in-person. There were three major reasons for this study: (a) the increase in the development and use of online student services, (b) the increase of older students in higher education, and (c) further need to understand the unique experiences of older students in higher education. The case study design used an interpretive social science philosophical approach. The study was conducted at a large multi-campus community college in a metropolitan area located in the Northwest. A combination of survey, interviews, institutional data, and student-journals were used to answer the following research questions: (a) What is the experience of older students with web-based technology in a community college setting, (b) How do the older students' overall experiences and use of web-based services affect their community college experience, and (c) How might older students' background and experiences with web-based student services inform community college policy and practice? Close examination of data revealed several major themes of older students' experiences with online student services. These themes are: • Student Assumptions • Self-Motivation • Influence of Prior Work Experiences • User Preferences • How and What Online Services are Used • User Suggestions When these themes are taken into consideration with related literature on the digital divide, technology use in student affairs, older student experiences in the community college, and older students' use of technology, this study offers implications for community college leaders and practitioners in the student affairs and technology development. The implications of this study may impact online service development, assessment of computer literacy, program enhancement or development, and technical changes. Close

• 726. [Article] Microcosm studies of bioaugmentation with a butane-utilizing mixed culture : microbial community structure and 1,1-DCE cometabolism

  The 1,1-dichloroethene (1,1-DCE) cometabolic transformation abilities of indigenous and bioaugmented microorganisms were compared in microcosms constructed with groundwater and aquifer solids from the ...

  Citation × Citation Citation Abstract Copy Title: Microcosm studies of bioaugmentation with a butane-utilizing mixed culture : microbial community structure and 1,1-DCE cometabolism Author: Lim, Hee Kyung The 1,1-dichloroethene (1,1-DCE) cometabolic transformation abilities of indigenous and bioaugmented microorganisms were compared in microcosms constructed with groundwater and aquifer solids from the Moffett Field site, CA. Microbial community structure in the microcosms and possible community shifts due to 1,1-DCE transformation stress was evaluated by terminal restriction fragment length polymorphism method (T-RFLP). An existing biotransformation model was used to simulate the experimental data using parameter values determined by Kim et al. (2002) and Rungkamol (2001) with small adjustments to the parameter values. The laboratory microcosm studies showed that both indigenous and bioaugmented butane utilizers were capable of transforming 1,1-DCE when fed butane as a primary substrate. A butane-grown enriched culture was bioaugmented into the microcosms and exposed to several repeated additions of butane and/or 1,1-DCE, ranging from 7.1 to 76 μmol and from 0.17 to 1.99 μmol, respectively. The bioaugmented butane-utilizers showed a reduced lag period compared to the indigenous butane-utilizers. The greatest ability to transform 1,1-DCE was observed in bioaugmented microcosms, simultaneously exposed to butane and 1,1-DCE. Very little 1,1-DCE was transformed in the bioaugmented microcosms that were not fed butane, presumably due to lack of reductant supply and/or product toxicity of 1,1-DCE transformation. Microbial community analyses revealed similar results for replicate microcosms and differences in the community structure in microcosms subjected to different patterns of substrate addition and 1,1-DCE cometabolism. 1,1-DCE transformation resulted in temporal fluctuations in specific bacterial groups in the bioaugmented microcosms. It could be inferred that microorganisms, correlated with the T-RFL of 183 base pair (bp) were generally predominant in butane-fed bioaugmented microcosms simultaneously exposed to 1,1-DCE. Bioaugmented microcosms that were pre-exposed to 1,1-DCE for 29 days in the absence of growth substrate, followed by the addition of butane showed a significantly different microbial community from bioaugmented microcosms fed butane and 1,1-DCE simultaneously. Microorganisms with T-RFL of 179 or 277.8 bp dominated in these microcosms. These differences were possibly the result of extensive 1,1-DCE transformation product toxicity during the pre-exposure phase of the tests. A model developed by Kim et al. (2002) was used to mathematically describe the rate and extent of butane utilization and the cometabolic transformation of 1,1-DCE in the microcosm tests. Using the kinetic parameter values previously determined by Kim et al. (2002) and Rungkamol (2001), heuristic fits were obtained between the experimental data and model simulations. The model successfully predicted the trend of the butane utilization and 1,1-DCE transformation. The model outputs were statistically quantified for their fit to the experimental data by estimating Standard Error of Estimate (SEE). A reasonable fit between model predictions and experimental observations was achieved. A significant contribution of this study was developing the laboratory methods to evaluate the microbial abilities to cometabolize 1,1-DCE and determining the communities of microorganisms correlated with those biotransformation activities. Furthermore, the model comparison to experimental data indicated that there was a potential in using the existing model to predict and improve bioremediation strategies. The results showed the successful bioaugmentation of a butane-utilizing culture to improve transformation performance. Title: Microcosm studies of bioaugmentation with a butane-utilizing mixed culture : microbial community structure and 1,1-DCE cometabolism Author: Lim, Hee Kyung The 1,1-dichloroethene (1,1-DCE) cometabolic transformation abilities of indigenous and bioaugmented microorganisms were compared in microcosms constructed with groundwater and aquifer solids from the Moffett Field site, CA. Microbial community structure in the microcosms and possible community shifts due to 1,1-DCE transformation stress was evaluated by terminal restriction fragment length polymorphism method (T-RFLP). An existing biotransformation model was used to simulate the experimental data using parameter values determined by Kim et al. (2002) and Rungkamol (2001) with small adjustments to the parameter values. The laboratory microcosm studies showed that both indigenous and bioaugmented butane utilizers were capable of transforming 1,1-DCE when fed butane as a primary substrate. A butane-grown enriched culture was bioaugmented into the microcosms and exposed to several repeated additions of butane and/or 1,1-DCE, ranging from 7.1 to 76 μmol and from 0.17 to 1.99 μmol, respectively. The bioaugmented butane-utilizers showed a reduced lag period compared to the indigenous butane-utilizers. The greatest ability to transform 1,1-DCE was observed in bioaugmented microcosms, simultaneously exposed to butane and 1,1-DCE. Very little 1,1-DCE was transformed in the bioaugmented microcosms that were not fed butane, presumably due to lack of reductant supply and/or product toxicity of 1,1-DCE transformation. Microbial community analyses revealed similar results for replicate microcosms and differences in the community structure in microcosms subjected to different patterns of substrate addition and 1,1-DCE cometabolism. 1,1-DCE transformation resulted in temporal fluctuations in specific bacterial groups in the bioaugmented microcosms. It could be inferred that microorganisms, correlated with the T-RFL of 183 base pair (bp) were generally predominant in butane-fed bioaugmented microcosms simultaneously exposed to 1,1-DCE. Bioaugmented microcosms that were pre-exposed to 1,1-DCE for 29 days in the absence of growth substrate, followed by the addition of butane showed a significantly different microbial community from bioaugmented microcosms fed butane and 1,1-DCE simultaneously. Microorganisms with T-RFL of 179 or 277.8 bp dominated in these microcosms. These differences were possibly the result of extensive 1,1-DCE transformation product toxicity during the pre-exposure phase of the tests. A model developed by Kim et al. (2002) was used to mathematically describe the rate and extent of butane utilization and the cometabolic transformation of 1,1-DCE in the microcosm tests. Using the kinetic parameter values previously determined by Kim et al. (2002) and Rungkamol (2001), heuristic fits were obtained between the experimental data and model simulations. The model successfully predicted the trend of the butane utilization and 1,1-DCE transformation. The model outputs were statistically quantified for their fit to the experimental data by estimating Standard Error of Estimate (SEE). A reasonable fit between model predictions and experimental observations was achieved. A significant contribution of this study was developing the laboratory methods to evaluate the microbial abilities to cometabolize 1,1-DCE and determining the communities of microorganisms correlated with those biotransformation activities. Furthermore, the model comparison to experimental data indicated that there was a potential in using the existing model to predict and improve bioremediation strategies. The results showed the successful bioaugmentation of a butane-utilizing culture to improve transformation performance. Close

• 727. [Article] The effects of irrigation water withdrawals on macroinvertebrate community structure and life history strategies

  I used current water management practices in central and eastern Oregon and Washington as natural experiments to quantify the effects of irrigation water withdrawals on macroinvertebrate community structure ...

  Citation × Citation Citation Abstract Copy Title: The effects of irrigation water withdrawals on macroinvertebrate community structure and life history strategies Author: Miller, Scott W. I used current water management practices in central and eastern Oregon and Washington as natural experiments to quantify the effects of irrigation water withdrawals on macroinvertebrate community structure and life history strategies. Reduced discharge had direct (e.g. decreased velocity and wetted habitat) and indirect (e.g. increased conductivity and temperature) effects on key environmental determinants of macroinvertebrate communities and life history strategies. In general, macroinvertebrate responses were more strongly related to indirect than direct environmental alterations. For a lowland river system, the severity of community and population level responses depended on the magnitude and duration of low flow events. However, discharge reductions alone, even when exceeding 90% of ambient levels, had no effect on community composition. Rather, changes in community composition were associated with interacting thresholds of reduced discharge and altered water quality (i.e., increased conductivity and temperature). Similar responses were observed at the population level; growth and development alterations for Brachycentrus occidentalis appeared to reduce fitness during high-intensity, long-duration water withdrawals associated with increased temperature. Winter discharge levels facilitated recovery of macroinvertebrate communities on an annual basis, whereas recovery was not observed after discharge and physicochemical variables returned to predisturbance conditions for only one month. At a broader spatial scale, I examined whether macroinvertebrate responses to water withdrawals of similar magnitude and duration depended on species traits (e.g., voltinism, thermal preference, size) for 12 rivers spanning an altitudinal gradient. Species traits differed among high, mid, and low elevation reference reaches; however, compositional responses to water withdrawals were similar among rivers found at different elevations. Apart from significant density increases, I was unable to detect compositional responses above and below all 12 diversions, despite discharge reduction exceeding 75% of ambient levels. In contrast, the proportional abundance for 10 of 52 species traits (e.g., multivoltinism, streamlined, swimmers) significantly differed above and below all points of diversion. Irrigation water withdrawals appear to impact macroinvertebrates through indirect environmental alterations that intensify with the magnitude and duration of water withdrawals. Preserving environmental conditions within natural ranges of variability, especially during low water years, appears critical to mitigating adverse biological responses to water withdrawals. Title: The effects of irrigation water withdrawals on macroinvertebrate community structure and life history strategies Author: Miller, Scott W. I used current water management practices in central and eastern Oregon and Washington as natural experiments to quantify the effects of irrigation water withdrawals on macroinvertebrate community structure and life history strategies. Reduced discharge had direct (e.g. decreased velocity and wetted habitat) and indirect (e.g. increased conductivity and temperature) effects on key environmental determinants of macroinvertebrate communities and life history strategies. In general, macroinvertebrate responses were more strongly related to indirect than direct environmental alterations. For a lowland river system, the severity of community and population level responses depended on the magnitude and duration of low flow events. However, discharge reductions alone, even when exceeding 90% of ambient levels, had no effect on community composition. Rather, changes in community composition were associated with interacting thresholds of reduced discharge and altered water quality (i.e., increased conductivity and temperature). Similar responses were observed at the population level; growth and development alterations for Brachycentrus occidentalis appeared to reduce fitness during high-intensity, long-duration water withdrawals associated with increased temperature. Winter discharge levels facilitated recovery of macroinvertebrate communities on an annual basis, whereas recovery was not observed after discharge and physicochemical variables returned to predisturbance conditions for only one month. At a broader spatial scale, I examined whether macroinvertebrate responses to water withdrawals of similar magnitude and duration depended on species traits (e.g., voltinism, thermal preference, size) for 12 rivers spanning an altitudinal gradient. Species traits differed among high, mid, and low elevation reference reaches; however, compositional responses to water withdrawals were similar among rivers found at different elevations. Apart from significant density increases, I was unable to detect compositional responses above and below all 12 diversions, despite discharge reduction exceeding 75% of ambient levels. In contrast, the proportional abundance for 10 of 52 species traits (e.g., multivoltinism, streamlined, swimmers) significantly differed above and below all points of diversion. Irrigation water withdrawals appear to impact macroinvertebrates through indirect environmental alterations that intensify with the magnitude and duration of water withdrawals. Preserving environmental conditions within natural ranges of variability, especially during low water years, appears critical to mitigating adverse biological responses to water withdrawals. Close

• 728. [Article] More than colleagues : tracing the experiences of career and technical education instructors engaged in faculty-to-faculty mentoring programs

  The purpose of this study was to understand the impact of faculty-to-faculty mentoring programs on the experiences of both mentors and first-year instructor protégés in Career and Technical Education (CTE) ...

  Citation × Citation Citation Abstract Copy Title: More than colleagues : tracing the experiences of career and technical education instructors engaged in faculty-to-faculty mentoring programs Author: Findley, Daniel E. The purpose of this study was to understand the impact of faculty-to-faculty mentoring programs on the experiences of both mentors and first-year instructor protégés in Career and Technical Education (CTE) programs with an emphasis on practitioner-educators in nursing and in welding-fabrication. The study was undertaken for four reasons: (a) increases in retirement rates force extensive replacement of experienced community college CTE faculty, (b) teaching effectiveness is linked to student success and is often predicated on experience and the application of best andragogical practices, (c) mentoring constitutes effective preparation for new professionals, and (d) given the demands placed on community colleges to educate learners and provide for a robust workforce, faculty preparation constitutes a significant challenge for community college leaders well into the future. The research design used an interpretive social science philosophical approach and the method of hermeneutic phenomenology. Ten faculty from three community colleges were interviewed in order to understand: (a) what they viewed as the key elements in a mentoring initiative, (b) how the elements of mentoring influence the experiences of first-year faculty, and (c) what common themes emerged concerning mentoring experiences that participants self-describe as successful. Impressions and statements drawn from the interviews were examined to show how the participants viewed their experiences within the mentoring relationship and how such experiences played a part in their lives as practitioner-educators. Aspects of mentoring experiences that participants identified as both present and high yield in nature included collaboration, reciprocity in relationships, a dedication to continuous improvement in both program and individual performance, access to experiences that constituted a source of renewal for programs and educators, and the existence of transformative experiences that lead to growth and satisfaction. Analysis of participant statements identified the needs of novice instructors coming to the community college learning environment for the first time and suggested experiences that may support them in their andragogical growth. Among the insights drawn from the study are the following: Providing authentic growth experiences that work may positively affect faculty retention and satisfaction. Institutional initiatives can be deemed successful only if they have a positive impact on students and the achievement of their outcomes. Taking into consideration these insights, related recent literature on mentoring, and the lived experiences of practicing CTE instructors as shared through their interviews, this study offers implications for community college leaders responsible for shaping and nurturing the faculty in a time of competitive job opportunities, unprecedented retirements, and scarcity of resources in an increasingly-complex environment. The manner in which these parameters are addressed may likely affect institutional success and prestige, faculty retention and satisfaction, student success, and long-term program viability. Title: More than colleagues : tracing the experiences of career and technical education instructors engaged in faculty-to-faculty mentoring programs Author: Findley, Daniel E. The purpose of this study was to understand the impact of faculty-to-faculty mentoring programs on the experiences of both mentors and first-year instructor protégés in Career and Technical Education (CTE) programs with an emphasis on practitioner-educators in nursing and in welding-fabrication. The study was undertaken for four reasons: (a) increases in retirement rates force extensive replacement of experienced community college CTE faculty, (b) teaching effectiveness is linked to student success and is often predicated on experience and the application of best andragogical practices, (c) mentoring constitutes effective preparation for new professionals, and (d) given the demands placed on community colleges to educate learners and provide for a robust workforce, faculty preparation constitutes a significant challenge for community college leaders well into the future. The research design used an interpretive social science philosophical approach and the method of hermeneutic phenomenology. Ten faculty from three community colleges were interviewed in order to understand: (a) what they viewed as the key elements in a mentoring initiative, (b) how the elements of mentoring influence the experiences of first-year faculty, and (c) what common themes emerged concerning mentoring experiences that participants self-describe as successful. Impressions and statements drawn from the interviews were examined to show how the participants viewed their experiences within the mentoring relationship and how such experiences played a part in their lives as practitioner-educators. Aspects of mentoring experiences that participants identified as both present and high yield in nature included collaboration, reciprocity in relationships, a dedication to continuous improvement in both program and individual performance, access to experiences that constituted a source of renewal for programs and educators, and the existence of transformative experiences that lead to growth and satisfaction. Analysis of participant statements identified the needs of novice instructors coming to the community college learning environment for the first time and suggested experiences that may support them in their andragogical growth. Among the insights drawn from the study are the following: Providing authentic growth experiences that work may positively affect faculty retention and satisfaction. Institutional initiatives can be deemed successful only if they have a positive impact on students and the achievement of their outcomes. Taking into consideration these insights, related recent literature on mentoring, and the lived experiences of practicing CTE instructors as shared through their interviews, this study offers implications for community college leaders responsible for shaping and nurturing the faculty in a time of competitive job opportunities, unprecedented retirements, and scarcity of resources in an increasingly-complex environment. The manner in which these parameters are addressed may likely affect institutional success and prestige, faculty retention and satisfaction, student success, and long-term program viability. Close

• 729. [Article] Returning grain to the lower-Willamette Valley : prospects and barriers for local food security

  A critical link is missing between food production and food consumption. This gap can be overcome by encouraging the production of staple food crops and emphasizing regional and community consumption of ...

  Citation × Citation Citation Abstract Copy Title: Returning grain to the lower-Willamette Valley : prospects and barriers for local food security Author: Malone, Chevelle P. A critical link is missing between food production and food consumption. This gap can be overcome by encouraging the production of staple food crops and emphasizing regional and community consumption of locally produced food. In order to re-establish local food security in the Willamette Valley, it is imperative that essential infrastructure be re-established in support of local food production and processing. To increase local food security, production of food crops within agricultural communities must increase, and grain infrastructure must be built to efficiently process locally grown grain. Using the case of the lower-Willamette Valley, this research seeks to answer three questions: 1) how has the agricultural history of grain crops and grass-seed in the lower-Willamette Valley changed since the European immigration, and does this history support a transition to grain crops; 2) what are the barriers to transitioning to grain crops in support of increased food security in this region; and 3) how does grain production, processing and infrastructure fit into the region's long-term food security and sustainability goals. These questions are answered by conducting a literature review to reveal the rise and fall of both grain and grass-seed in the region, and additionally using remotely sensed images to visually expound on the changed agricultural landscape of the lower-Willamette Valley for three consecutive decades. Interviews and focus groups with regional grass-seed and grain farmers illuminate numerous barriers to transitioning to grain crops. Lack of grain infrastructure was noted as a major barrier to increasing food security through local food production. In order to illustrate the connection between grain infrastructure and food security, ArcGIS is used to map out grain infrastructure within the study area. Lastly, the imagery of the changing landscape and the grain infrastructure map are examined in conjunction with community food security and sustainability goals in the cities of Eugene and Corvallis, Oregon to assist these communities in reaching their food security and sustainability goals. This research determines that re-energizing the Willamette Valley grain-market by way of the local food security and community sustainability efforts is only effective if done collaboratively between farmers, local businesses, city and county leadership and the community because of the innate difference between the national-international market where grass-seed is prevalent and the local-regional market of grain. Title: Returning grain to the lower-Willamette Valley : prospects and barriers for local food security Author: Malone, Chevelle P. A critical link is missing between food production and food consumption. This gap can be overcome by encouraging the production of staple food crops and emphasizing regional and community consumption of locally produced food. In order to re-establish local food security in the Willamette Valley, it is imperative that essential infrastructure be re-established in support of local food production and processing. To increase local food security, production of food crops within agricultural communities must increase, and grain infrastructure must be built to efficiently process locally grown grain. Using the case of the lower-Willamette Valley, this research seeks to answer three questions: 1) how has the agricultural history of grain crops and grass-seed in the lower-Willamette Valley changed since the European immigration, and does this history support a transition to grain crops; 2) what are the barriers to transitioning to grain crops in support of increased food security in this region; and 3) how does grain production, processing and infrastructure fit into the region's long-term food security and sustainability goals. These questions are answered by conducting a literature review to reveal the rise and fall of both grain and grass-seed in the region, and additionally using remotely sensed images to visually expound on the changed agricultural landscape of the lower-Willamette Valley for three consecutive decades. Interviews and focus groups with regional grass-seed and grain farmers illuminate numerous barriers to transitioning to grain crops. Lack of grain infrastructure was noted as a major barrier to increasing food security through local food production. In order to illustrate the connection between grain infrastructure and food security, ArcGIS is used to map out grain infrastructure within the study area. Lastly, the imagery of the changing landscape and the grain infrastructure map are examined in conjunction with community food security and sustainability goals in the cities of Eugene and Corvallis, Oregon to assist these communities in reaching their food security and sustainability goals. This research determines that re-energizing the Willamette Valley grain-market by way of the local food security and community sustainability efforts is only effective if done collaboratively between farmers, local businesses, city and county leadership and the community because of the innate difference between the national-international market where grass-seed is prevalent and the local-regional market of grain. Close

• 730. [Article] Community Perception Towards a Set Back Area : A Case Study in Galle District, Sri Lanka

  In view of the coastal areas, vulnerability to natural hazards particularly tsunami, earthquakes, etc, are rather increasing. The tsunami, giant tidal waves struck on 26th of December 2004 caused severe ...

  Citation × Citation Citation Abstract Copy Title: Community Perception Towards a Set Back Area : A Case Study in Galle District, Sri Lanka Author: Koralagama, Dilanthi In view of the coastal areas, vulnerability to natural hazards particularly tsunami, earthquakes, etc, are rather increasing. The tsunami, giant tidal waves struck on 26th of December 2004 caused severe damage to people and their livelihood. It is now felt that the country should enforce a regulation procedure to manage the coastal zone. This addresses the concept of a set back area in order to mitigate the severity of natural disasters. But, the promulgation of set back area should be account for community perception. Hence, this study was aimed to assess the community perception, possible constraints, and to extract criteria to demarcate a set back area in the littoral. The study was carried out in Galle district, in Southern Sri Lanka, which is one of the districts greatly affected by the tsunami. Three divisional secretariat (DS) divisions viz; Habaraduwa, Hikkaduwa and Galle were selected. Simple random sampling was used to select 120 households. Primary data were gleaned using a pre-tested questionnaire. Informal discussions were held with coastal dwellers, government officers, &etc. The data were analyzed and evaluated to assess the objectives. Accordingly, 54 percent of the community is involved in activities based on fisheries and tourism. The rest 46 percent are engaged in other activities, which are non-stationed in the coastal zone. More than 80 percent households of the area are vulnerable for natural disasters. In consequence, 66 percent were fully damaged and 34 percent were partially damaged. Totally 76 percent of the villagers are willing to have a set back area. But, only 48 percent from 100 m boundary, agreed to have a buffer zone and majority (52%) did not want to leave the place. The reason is that their livelihood activities are adhered to the shore. Further, the buffer zone would reduce the land use efficiency since, it requires 0.25 percent land area. Hence, it is advisable to maintain a buffer zone with a green belt, which is most effective to abate the sea waves. The demarcation of a set back area should consider the geomorphology, natural vegetation cover, &etc. Moreover, government incentives, concessionary loans, permits &etc are tools to promote settlements in inland. Since, the community is in uncertainty and unsecured, willing to have more secured land strip as a buffer zone. Ipso facto, a set back area is a community-blessed concept to mitigate dreadful natural destructions and also to assure the sustainability of the area. Title: Community Perception Towards a Set Back Area : A Case Study in Galle District, Sri Lanka Author: Koralagama, Dilanthi In view of the coastal areas, vulnerability to natural hazards particularly tsunami, earthquakes, etc, are rather increasing. The tsunami, giant tidal waves struck on 26th of December 2004 caused severe damage to people and their livelihood. It is now felt that the country should enforce a regulation procedure to manage the coastal zone. This addresses the concept of a set back area in order to mitigate the severity of natural disasters. But, the promulgation of set back area should be account for community perception. Hence, this study was aimed to assess the community perception, possible constraints, and to extract criteria to demarcate a set back area in the littoral. The study was carried out in Galle district, in Southern Sri Lanka, which is one of the districts greatly affected by the tsunami. Three divisional secretariat (DS) divisions viz; Habaraduwa, Hikkaduwa and Galle were selected. Simple random sampling was used to select 120 households. Primary data were gleaned using a pre-tested questionnaire. Informal discussions were held with coastal dwellers, government officers, &etc. The data were analyzed and evaluated to assess the objectives. Accordingly, 54 percent of the community is involved in activities based on fisheries and tourism. The rest 46 percent are engaged in other activities, which are non-stationed in the coastal zone. More than 80 percent households of the area are vulnerable for natural disasters. In consequence, 66 percent were fully damaged and 34 percent were partially damaged. Totally 76 percent of the villagers are willing to have a set back area. But, only 48 percent from 100 m boundary, agreed to have a buffer zone and majority (52%) did not want to leave the place. The reason is that their livelihood activities are adhered to the shore. Further, the buffer zone would reduce the land use efficiency since, it requires 0.25 percent land area. Hence, it is advisable to maintain a buffer zone with a green belt, which is most effective to abate the sea waves. The demarcation of a set back area should consider the geomorphology, natural vegetation cover, &etc. Moreover, government incentives, concessionary loans, permits &etc are tools to promote settlements in inland. Since, the community is in uncertainty and unsecured, willing to have more secured land strip as a buffer zone. Ipso facto, a set back area is a community-blessed concept to mitigate dreadful natural destructions and also to assure the sustainability of the area. Close