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• 31. [Article] A comparison of freshmen attending selected Oregon community colleges and Oregon State University in terms of interests, values, and manifest needs

  The primary purpose of this study was to determine whether there were significant differences between Oregon community college collegiate freshmen and Oregon State University freshmen in terms of interest, ...

  Citation × Citation Citation Abstract Copy Title: A comparison of freshmen attending selected Oregon community colleges and Oregon State University in terms of interests, values, and manifest needs Author: Howard, Lorraine Harris The primary purpose of this study was to determine whether there were significant differences between Oregon community college collegiate freshmen and Oregon State University freshmen in terms of interest, values, and manifest needs. The study was limited to a representative sample of the freshman population in the lower-division collegiate program at three selected Oregon community colleges and to a representative sample of Oregon State University. The Strong Vocational Interest Blank for Men, the Allport-Vernon-Lindzey Study of Values, the Edwards Personal Preference Schedule, and a Personal Data Schedule were administered to 499 first-term male and female freshmen who were enrolled at these institutions for the fall term of 1963. The responses of the freshmen on the psychological tests were treated statistically by analysis of variance, and the responses on the Personal Data Schedule were converted to percentages and analyzed using the t-test. Significant differences were evident among the responses of the Oregon State University and community college males and females on the Personal Data Schedule. There were 32 items that differentiated between the community college and Oregon State University males at the 1 percent level and six items at the 5 percent level. There were 28 items that differentiated between the community college females at the 1 percent level and four that differentiated at the 5 percent level. On the Study of Values, Oregon State University males showed a higher mean score on the Theoretical scale than did the community college males. On the Social scale the community college males had a higher mean score than that of the Oregon State University males. Females at Oregon State University showed a higher mean score on the Economic scale than did the community college females, while the community college females had a higher mean score on the Religious scale than did the females at Oregon State University. There were many significant differences between the interests of Oregon State University males and community college males. Males at Oregon State University had substantially higher interest scores on the Strong Vocational Interest Inventory than did the community college males in Groups I and II, while community college males had considerably higher interest scores than did Oregon State University males in Groups VIII and IX. None of the scores on the occupational scales yielded significant differences among the mean scores of females attending Oregon State University and the community college females. Scores on the non-occupational scales, the Specialization Level and Occupational Level, differentiated between Oregon State University and community college males. The Oregon State University males scored higher than the community college males on both of these scales. The Occupational Level scale differentiated between Oregon State University and community college females and the Oregon State University females obtained the higher mean score. The least amount of difference between the mean occupational scores of the community college males and the mean occupational scores of Oregon State University males in the various major schools was found in the scores of the humanities majors when the miscellaneous category was excluded from the comparison. The greatest discrepancy in these occupational scores was found in the responses of males in engineering and science. The scores of the Oregon State University females in education most closely resembled the scores of the community college females, and the occupational scores of females that were least like the scores of community college females were those of the females in business and technology. Responses on the Study of Values and the Strong Vocational Interest Inventory indicated marked differences with respect to population characteristics in interests and values of freshmen attending community colleges and of freshmen attending Oregon State University. However, the responses on the Edwards Personal Preference Schedule show no evidence of differences among the personality characteristics of the freshmen. Title: A comparison of freshmen attending selected Oregon community colleges and Oregon State University in terms of interests, values, and manifest needs Author: Howard, Lorraine Harris The primary purpose of this study was to determine whether there were significant differences between Oregon community college collegiate freshmen and Oregon State University freshmen in terms of interest, values, and manifest needs. The study was limited to a representative sample of the freshman population in the lower-division collegiate program at three selected Oregon community colleges and to a representative sample of Oregon State University. The Strong Vocational Interest Blank for Men, the Allport-Vernon-Lindzey Study of Values, the Edwards Personal Preference Schedule, and a Personal Data Schedule were administered to 499 first-term male and female freshmen who were enrolled at these institutions for the fall term of 1963. The responses of the freshmen on the psychological tests were treated statistically by analysis of variance, and the responses on the Personal Data Schedule were converted to percentages and analyzed using the t-test. Significant differences were evident among the responses of the Oregon State University and community college males and females on the Personal Data Schedule. There were 32 items that differentiated between the community college and Oregon State University males at the 1 percent level and six items at the 5 percent level. There were 28 items that differentiated between the community college females at the 1 percent level and four that differentiated at the 5 percent level. On the Study of Values, Oregon State University males showed a higher mean score on the Theoretical scale than did the community college males. On the Social scale the community college males had a higher mean score than that of the Oregon State University males. Females at Oregon State University showed a higher mean score on the Economic scale than did the community college females, while the community college females had a higher mean score on the Religious scale than did the females at Oregon State University. There were many significant differences between the interests of Oregon State University males and community college males. Males at Oregon State University had substantially higher interest scores on the Strong Vocational Interest Inventory than did the community college males in Groups I and II, while community college males had considerably higher interest scores than did Oregon State University males in Groups VIII and IX. None of the scores on the occupational scales yielded significant differences among the mean scores of females attending Oregon State University and the community college females. Scores on the non-occupational scales, the Specialization Level and Occupational Level, differentiated between Oregon State University and community college males. The Oregon State University males scored higher than the community college males on both of these scales. The Occupational Level scale differentiated between Oregon State University and community college females and the Oregon State University females obtained the higher mean score. The least amount of difference between the mean occupational scores of the community college males and the mean occupational scores of Oregon State University males in the various major schools was found in the scores of the humanities majors when the miscellaneous category was excluded from the comparison. The greatest discrepancy in these occupational scores was found in the responses of males in engineering and science. The scores of the Oregon State University females in education most closely resembled the scores of the community college females, and the occupational scores of females that were least like the scores of community college females were those of the females in business and technology. Responses on the Study of Values and the Strong Vocational Interest Inventory indicated marked differences with respect to population characteristics in interests and values of freshmen attending community colleges and of freshmen attending Oregon State University. However, the responses on the Edwards Personal Preference Schedule show no evidence of differences among the personality characteristics of the freshmen. Close

• 32. [Article] Twenty years of research on fungus-microbe-plant interactions on Lyman Glacier forefront – lessons learned and questions yet unanswered

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/fungal-ecology/...

  Citation × Citation Citation Abstract Copy Title: Twenty years of research on fungus-microbe-plant interactions on Lyman Glacier forefront – lessons learned and questions yet unanswered Author: Trappe, James M., Strommer, Rauni, Jumpponen, Ari, Cazares, Efren, Brown, Shawn P. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/fungal-ecology/. Title: Twenty years of research on fungus-microbe-plant interactions on Lyman Glacier forefront – lessons learned and questions yet unanswered Author: Trappe, James M., Strommer, Rauni, Jumpponen, Ari, Cazares, Efren, Brown, Shawn P. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/fungal-ecology/. Close

• 33. [Article] Two Oregon governors : the role of perceptions in community college state budget development

  The purpose of this phenomenological study is to describe how Oregon governors Barbara Roberts and John Kitzhaber, whose tenures both coincided with the passage and implementation of property tax limitation ...

  Citation × Citation Citation Abstract Copy Title: Two Oregon governors : the role of perceptions in community college state budget development Author: Preus, Camille The purpose of this phenomenological study is to describe how Oregon governors Barbara Roberts and John Kitzhaber, whose tenures both coincided with the passage and implementation of property tax limitation measures, determined the community college budgets within their recommended state budgets. The stories of Robert’s 1993 and Kitzhaber’s 2001 decisions are explored and analyzed to assess what influences, experiences, and information impacted each governor’s decision-making for community college funding. This study confirms the role of the governor in the budget decision-making process as one of ‘chief legislator’ or arbiter of the final budget. The findings call for community college leaders to get to know their governors and those individuals close to the governor who are responsible for providing advice on education and community college policies and budgets. Interactions should lead to a clear understanding of the administration’s policy priorities and the placement of education and community colleges among those priorities. Greater knowledge of the priorities will enable community college leaders to build a relationship grounded in a recognition and awareness of these priorities and provide the basis for influencing the governor’s overall perception of community colleges. Development of community college messages should be framed around the governor’s perceptions and priorities for optimal impact. This study finds that there are other influential players in the state-level budget development and decision-making process. As discussed above, the policy advisors close to the governor provided important influences of perception and decisionmaking. Community college leaders must build relationships with a governor’s education policy advisors, as they have access and opportunity to influence the governor’s perceptions and decisions, since they act as translators, interceptors and gatekeepers. Successful relationships with education policy advisors will lead to better understanding of policy priorities and, again, the ability to frame the community college message for maximum influence and impact. Community college leaders must also be familiar with the state-level budgeting process and timeline to ensure that the messages are most effectively delivered and within the established timeframe. Title: Two Oregon governors : the role of perceptions in community college state budget development Author: Preus, Camille The purpose of this phenomenological study is to describe how Oregon governors Barbara Roberts and John Kitzhaber, whose tenures both coincided with the passage and implementation of property tax limitation measures, determined the community college budgets within their recommended state budgets. The stories of Robert’s 1993 and Kitzhaber’s 2001 decisions are explored and analyzed to assess what influences, experiences, and information impacted each governor’s decision-making for community college funding. This study confirms the role of the governor in the budget decision-making process as one of ‘chief legislator’ or arbiter of the final budget. The findings call for community college leaders to get to know their governors and those individuals close to the governor who are responsible for providing advice on education and community college policies and budgets. Interactions should lead to a clear understanding of the administration’s policy priorities and the placement of education and community colleges among those priorities. Greater knowledge of the priorities will enable community college leaders to build a relationship grounded in a recognition and awareness of these priorities and provide the basis for influencing the governor’s overall perception of community colleges. Development of community college messages should be framed around the governor’s perceptions and priorities for optimal impact. This study finds that there are other influential players in the state-level budget development and decision-making process. As discussed above, the policy advisors close to the governor provided important influences of perception and decisionmaking. Community college leaders must build relationships with a governor’s education policy advisors, as they have access and opportunity to influence the governor’s perceptions and decisions, since they act as translators, interceptors and gatekeepers. Successful relationships with education policy advisors will lead to better understanding of policy priorities and, again, the ability to frame the community college message for maximum influence and impact. Community college leaders must also be familiar with the state-level budgeting process and timeline to ensure that the messages are most effectively delivered and within the established timeframe. Close

• 34. [Article] Ecology of riparian plant communities in southern Malheur National Forest

  Riparian communities in the southern portion of Malheur National Forest were intensively studied with the objective of designing an approach for classifying disturbed riparian areas into units of similar ...

  Citation × Citation Citation Abstract Copy Title: Ecology of riparian plant communities in southern Malheur National Forest Author: Padgett, Wayne G. Riparian communities in the southern portion of Malheur National Forest were intensively studied with the objective of designing an approach for classifying disturbed riparian areas into units of similar potential. Not all riparian community types in this portion of the Blue Mountains were sampled due to time limitations. Some of the major community types sampled included: Baltic rush (Juncus balticus) communities; Kentucky bluegrass (Poa pratensis) communities; beaked sedge (Carex rostrata) communities; water sedge (Carex aquatilis) communities; mountain alder (Alnus incana) communities; and various willow communities (Salix geyeriana, Salix exigua ssp. exigua, Salix rigida var. mackenziana, and Salix lemmonii). Sites were selected to maximize geographic variation. Piezometers were placed at each site to determine depth to water table. Soil temperature at depths of 15 cm and 50 cm and water table depth were measured semi-weekly. Plant frequency and understory cover by species were determined using 25 cm square plot frames along three 10 m transects in each community sampled. Belt transects were run to determine tree and shrub densities. Tree cover was determined using a hand-held densiometer and the line-intercept method was used for shrub cover. Soils were described and samples were collected from each horizon for laboratory determination of percent organic carbon, soil texture, and reaction (pH). Ordinations of plant communities and plant species were calculated using the DECORANA program for detrended correspondence analysis. The first axis of ordination arranged both species and communities along a moisture gradient. This was verified by correlation analysis as well as through canonical correlation of a species matrix and an environmental matrix. Stand ordination tables combined with water table and soils data were employed in separating these communities into units of similar vegetative potential (Riparian dominance types). Use of these riparian dominance types may improve management of riparian zones in this part of the Blue Mountains and the use of these types is encouraged. Title: Ecology of riparian plant communities in southern Malheur National Forest Author: Padgett, Wayne G. Riparian communities in the southern portion of Malheur National Forest were intensively studied with the objective of designing an approach for classifying disturbed riparian areas into units of similar potential. Not all riparian community types in this portion of the Blue Mountains were sampled due to time limitations. Some of the major community types sampled included: Baltic rush (Juncus balticus) communities; Kentucky bluegrass (Poa pratensis) communities; beaked sedge (Carex rostrata) communities; water sedge (Carex aquatilis) communities; mountain alder (Alnus incana) communities; and various willow communities (Salix geyeriana, Salix exigua ssp. exigua, Salix rigida var. mackenziana, and Salix lemmonii). Sites were selected to maximize geographic variation. Piezometers were placed at each site to determine depth to water table. Soil temperature at depths of 15 cm and 50 cm and water table depth were measured semi-weekly. Plant frequency and understory cover by species were determined using 25 cm square plot frames along three 10 m transects in each community sampled. Belt transects were run to determine tree and shrub densities. Tree cover was determined using a hand-held densiometer and the line-intercept method was used for shrub cover. Soils were described and samples were collected from each horizon for laboratory determination of percent organic carbon, soil texture, and reaction (pH). Ordinations of plant communities and plant species were calculated using the DECORANA program for detrended correspondence analysis. The first axis of ordination arranged both species and communities along a moisture gradient. This was verified by correlation analysis as well as through canonical correlation of a species matrix and an environmental matrix. Stand ordination tables combined with water table and soils data were employed in separating these communities into units of similar vegetative potential (Riparian dominance types). Use of these riparian dominance types may improve management of riparian zones in this part of the Blue Mountains and the use of these types is encouraged. Close

• 35. [Article] Do Community Development Financial Institutions Promote Economic Growth in Neighborhoods? A Multi-Metro Area Analysis of Home Values

  2017

  Citation × Citation Citation Abstract Copy Title: Do Community Development Financial Institutions Promote Economic Growth in Neighborhoods? A Multi-Metro Area Analysis of Home Values Author: McRae, Caitlin 2017 Title: Do Community Development Financial Institutions Promote Economic Growth in Neighborhoods? A Multi-Metro Area Analysis of Home Values Author: McRae, Caitlin 2017 Close

• 36. [Article] Exploring rural people's perceptions of weight-healthy attributes of community place

  (GROW) Healthy Kids and Communities

  Citation × Citation Citation Abstract Copy Title: Exploring rural people's perceptions of weight-healthy attributes of community place Author: Jamieson, Bridget (GROW) Healthy Kids and Communities Title: Exploring rural people's perceptions of weight-healthy attributes of community place Author: Jamieson, Bridget (GROW) Healthy Kids and Communities Close

• 37. [Article] Transactional analysis applied to a community development issue

  Barth's theory of transactional analysis is applied to the community of Tiller, Oregon and its reaction to a development proposal. Community behavior patterns vis-a-vis the development proposal are examined ...

  Citation × Citation Citation Abstract Copy Title: Transactional analysis applied to a community development issue Author: Manolescu, Kathleen M. Barth's theory of transactional analysis is applied to the community of Tiller, Oregon and its reaction to a development proposal. Community behavior patterns vis-a-vis the development proposal are examined from a processual point of view to determine how these patterns are generated. The community's history and contemporary situation are described. Data derived from bibliographic and field research are presented to illustrate transactions involving reciprocity in the community. A generative model is formulated to depict the constraints and incentives channeling decision-making in the transactions. It is concluded that a transactional analysis is an appropriate tool for examining the community development process and for specifying critical elements in development. The analysis revealed cultural evaluations and therefore provided an indirect means for engaging citizen participation and for assessing the development proposal. Title: Transactional analysis applied to a community development issue Author: Manolescu, Kathleen M. Barth's theory of transactional analysis is applied to the community of Tiller, Oregon and its reaction to a development proposal. Community behavior patterns vis-a-vis the development proposal are examined from a processual point of view to determine how these patterns are generated. The community's history and contemporary situation are described. Data derived from bibliographic and field research are presented to illustrate transactions involving reciprocity in the community. A generative model is formulated to depict the constraints and incentives channeling decision-making in the transactions. It is concluded that a transactional analysis is an appropriate tool for examining the community development process and for specifying critical elements in development. The analysis revealed cultural evaluations and therefore provided an indirect means for engaging citizen participation and for assessing the development proposal. Close

• 38. [Article] Variation in communities of ammonia-oxidizing and denitrifying bacteria in Fennoscandian boreal forest soils

  The objective of this study was to examine the variation among ammonia-oxidizing and denitrifying communities in soils of a natural Fennoscandian boreal forest and of a forest with a long history of fertilization ...

  Citation × Citation Citation Abstract Copy Title: Variation in communities of ammonia-oxidizing and denitrifying bacteria in Fennoscandian boreal forest soils Author: Ghimire, Rama D. The objective of this study was to examine the variation among ammonia-oxidizing and denitrifying communities in soils of a natural Fennoscandian boreal forest and of a forest with a long history of fertilization with different levels of nitrogen (N), and to examine whether there are any changes in the microbial communities after the termination of N fertilizer. The natural forest at Betsele, Sweden, represents the inherent variation in N supply, plant productivity, and contrasting soil microbial communities. The long-term fertilized forest, Norrliden, represents an on-going N fertilization experiment with up to 34 years of annual N loading at four levels of ammonium nitrate additions, of which the highest was terminated 14 years ago. Although many studies in the past have been done with microbial communities related to the N cycle, the effect of N and N fertilizer on the ammonia-oxidizing and denitrifying communities is still unclear. Terminal restriction fragment length polymorphism (T-RFLP), a fingerprinting method, was used to examine the variation of the ammonia-oxidizer and the denitrifier communities. Functional biomarkers, the amoA gene for ammonia-oxidizing bacteria (AOB) and the nirK, nirS and nosZ genes for denitrifying bacteria, were subjected to PCR amplification. Amplification of ammonia-oxidizers was more successful in the soils with a higher level of N. The AOB community could be assessed only within the two fertilized plots, which showed a difference in the communities with different level of N fertilization. The difference in denitrifying communities regarding the nitrite reductase (nirK and nirS) and nitrous oxide reductase (nosZ) genes were found to be associated with pH and organic matter concentration in the natural forest at Betsele, followed by nitrate and ammonium concentrations. In the case of the fertilized forest, Norrliden, the community difference was driven predominantly by nitrate and ammonium concentrations, and pH. A fertilization effect was found in the nirK communities but this was less apparent with the nirS communities. The nosZ communities showed fertilization effects. The nirK and nirS communities each represent a part of the denitrifying community whereas the nosZ communities gave the entire picture of the denitrifying communities. Nevertheless, the nirS, nirK, and nosZ communities were all significantly correlated. A shift in the nosZ community was observed towards the control and less fertilized plots after the cessation of the fertilizer at Norrliden. The study of these functional genes provided insight about the variability of the microbial communities responsible for regulating important steps in the N cycle. Title: Variation in communities of ammonia-oxidizing and denitrifying bacteria in Fennoscandian boreal forest soils Author: Ghimire, Rama D. The objective of this study was to examine the variation among ammonia-oxidizing and denitrifying communities in soils of a natural Fennoscandian boreal forest and of a forest with a long history of fertilization with different levels of nitrogen (N), and to examine whether there are any changes in the microbial communities after the termination of N fertilizer. The natural forest at Betsele, Sweden, represents the inherent variation in N supply, plant productivity, and contrasting soil microbial communities. The long-term fertilized forest, Norrliden, represents an on-going N fertilization experiment with up to 34 years of annual N loading at four levels of ammonium nitrate additions, of which the highest was terminated 14 years ago. Although many studies in the past have been done with microbial communities related to the N cycle, the effect of N and N fertilizer on the ammonia-oxidizing and denitrifying communities is still unclear. Terminal restriction fragment length polymorphism (T-RFLP), a fingerprinting method, was used to examine the variation of the ammonia-oxidizer and the denitrifier communities. Functional biomarkers, the amoA gene for ammonia-oxidizing bacteria (AOB) and the nirK, nirS and nosZ genes for denitrifying bacteria, were subjected to PCR amplification. Amplification of ammonia-oxidizers was more successful in the soils with a higher level of N. The AOB community could be assessed only within the two fertilized plots, which showed a difference in the communities with different level of N fertilization. The difference in denitrifying communities regarding the nitrite reductase (nirK and nirS) and nitrous oxide reductase (nosZ) genes were found to be associated with pH and organic matter concentration in the natural forest at Betsele, followed by nitrate and ammonium concentrations. In the case of the fertilized forest, Norrliden, the community difference was driven predominantly by nitrate and ammonium concentrations, and pH. A fertilization effect was found in the nirK communities but this was less apparent with the nirS communities. The nosZ communities showed fertilization effects. The nirK and nirS communities each represent a part of the denitrifying community whereas the nosZ communities gave the entire picture of the denitrifying communities. Nevertheless, the nirS, nirK, and nosZ communities were all significantly correlated. A shift in the nosZ community was observed towards the control and less fertilized plots after the cessation of the fertilizer at Norrliden. The study of these functional genes provided insight about the variability of the microbial communities responsible for regulating important steps in the N cycle. Close

• 39. [Article] Breeding bird community composition in relation to riparian vegetation structure in grazed habitats

  Riparian zones provide habitat for breeding birds in the semiarid western United States; however, there are few data available that address the effects of livestock grazing strategies on riparian habitats ...

  Citation × Citation Citation Abstract Copy Title: Breeding bird community composition in relation to riparian vegetation structure in grazed habitats Author: Sanders, Todd Alan Riparian zones provide habitat for breeding birds in the semiarid western United States; however, there are few data available that address the effects of livestock grazing strategies on riparian habitats and avian communities. Documenting avian community composition in different riparian vegetation communities and relating vegetation communities to livestock grazing strategies may identify management alternatives that are sustainable from a wildlife habitat perspective, and may permit constructive coalitions between agricultural industry and environmental groups. I compared diurnal breeding bird abundance, individual species abundance, and species richness, and vegetation composition and structure among 12 streamside riparian areas of Bear and Silvies valleys in eastern Oregon during 1993 and 1994. Bird and vegetation data were collected along four replicate transects within each of three riparian vegetation communities characterized by vegetation structure: herbaceous, discontinuous willow (Salix spp.), and continuous willow. These riparian vegetation communities were grazed under summer season-long, summer short-duration, and fall short-duration livestock grazing strategies, respectively, >5 years before the study. Differences in riparian vegetation among communities were primarily related to shrub structure by experimental design. The continuous willow community had more shrub cover overall (P<0.001) and within each 1-m height interval from 0-4 m (P<0.013) than the herbaceous and discontinuous willow communities. The herbaceous community had no shrub cover >1 m in height. Willows extended farther (P=0.031) from the steam edge in the continuous willow community than in the discontinuous willow community. No willows were detected in the herbaceous community. I detected 4,016 birds representing 56 species along the transects. Total bird abundance was greater (P<0.001) in the continuous willow community than in the herbaceous and discontinuous willow communities. Species richness was inconsistent (P=0.034) between years within communities; it was greatest (P<0.037) in the continuous and discontinuous willow communities in 1993, and greatest (P<0.003) in the continuous willow community in 1994. Total bird abundance and species richness in 1994 increased with willow volume (r²>0.707, P<0.001). Of 23 bird species with >20 individual detections over both years, 13 species were most abundant in one or two vegetation communities (P<0.088). Seven species (yellow warbler [Dendroica petechia], song sparrow [Melospiza melodia], willow flycatcher [Empidonax traillii], American robin [Turdus migratorius], common snipe [Gallinago gallinago], bobolink [Dolichonyx oryzivorus], and Vaux's swift [Chaetura vauxi]) were most abundant in the continuous willow community. Three species (savannah sparrow [Passerculus sandwichensis], black tern [Chlidonias niger], and American wigeon [Anas americana]) were most abundant in the herbaceous community. Willets (Catoptrophorus semipalmatus) were most abundant in the herbaceous and discontinuous willow communities whereas cinnamon teal (A. cyanoptera) were most abundant in the herbaceous and continuous willow communities. Red-winged blackbirds (Ageliaus phoeniceus) were inconsistent (P=0.032) between years within communities: they were most abundant in the continuous willow community in 1993, and most abundant in the continuous willow and herbaceous communities in 1994. Hydrophytic woody vegetation within semiarid rangeland environments increases structural complexity and is associated with avian abundance and diversity. Yellow warblers, willow flycatchers, and song sparrows, which depend on hydrophytic shrubs for nesting almost exclusively in the semiarid West, are especially threatened by the elimination or simplification of woody riparian vegetation. I suggest that riparian vegetation structure and composition, which is associated with avian abundance, species richness, riparian associate bird species, and landscape-level biological diversity, be maintained where possible. Seasonal light (<30% use) fall short-duration grazing seemed to be compatible with the maintenance of woody riparian vegetation whereas summer season-long and summer short-duration grazing is likely incompatible. Title: Breeding bird community composition in relation to riparian vegetation structure in grazed habitats Author: Sanders, Todd Alan Riparian zones provide habitat for breeding birds in the semiarid western United States; however, there are few data available that address the effects of livestock grazing strategies on riparian habitats and avian communities. Documenting avian community composition in different riparian vegetation communities and relating vegetation communities to livestock grazing strategies may identify management alternatives that are sustainable from a wildlife habitat perspective, and may permit constructive coalitions between agricultural industry and environmental groups. I compared diurnal breeding bird abundance, individual species abundance, and species richness, and vegetation composition and structure among 12 streamside riparian areas of Bear and Silvies valleys in eastern Oregon during 1993 and 1994. Bird and vegetation data were collected along four replicate transects within each of three riparian vegetation communities characterized by vegetation structure: herbaceous, discontinuous willow (Salix spp.), and continuous willow. These riparian vegetation communities were grazed under summer season-long, summer short-duration, and fall short-duration livestock grazing strategies, respectively, >5 years before the study. Differences in riparian vegetation among communities were primarily related to shrub structure by experimental design. The continuous willow community had more shrub cover overall (P<0.001) and within each 1-m height interval from 0-4 m (P<0.013) than the herbaceous and discontinuous willow communities. The herbaceous community had no shrub cover >1 m in height. Willows extended farther (P=0.031) from the steam edge in the continuous willow community than in the discontinuous willow community. No willows were detected in the herbaceous community. I detected 4,016 birds representing 56 species along the transects. Total bird abundance was greater (P<0.001) in the continuous willow community than in the herbaceous and discontinuous willow communities. Species richness was inconsistent (P=0.034) between years within communities; it was greatest (P<0.037) in the continuous and discontinuous willow communities in 1993, and greatest (P<0.003) in the continuous willow community in 1994. Total bird abundance and species richness in 1994 increased with willow volume (r²>0.707, P<0.001). Of 23 bird species with >20 individual detections over both years, 13 species were most abundant in one or two vegetation communities (P<0.088). Seven species (yellow warbler [Dendroica petechia], song sparrow [Melospiza melodia], willow flycatcher [Empidonax traillii], American robin [Turdus migratorius], common snipe [Gallinago gallinago], bobolink [Dolichonyx oryzivorus], and Vaux's swift [Chaetura vauxi]) were most abundant in the continuous willow community. Three species (savannah sparrow [Passerculus sandwichensis], black tern [Chlidonias niger], and American wigeon [Anas americana]) were most abundant in the herbaceous community. Willets (Catoptrophorus semipalmatus) were most abundant in the herbaceous and discontinuous willow communities whereas cinnamon teal (A. cyanoptera) were most abundant in the herbaceous and continuous willow communities. Red-winged blackbirds (Ageliaus phoeniceus) were inconsistent (P=0.032) between years within communities: they were most abundant in the continuous willow community in 1993, and most abundant in the continuous willow and herbaceous communities in 1994. Hydrophytic woody vegetation within semiarid rangeland environments increases structural complexity and is associated with avian abundance and diversity. Yellow warblers, willow flycatchers, and song sparrows, which depend on hydrophytic shrubs for nesting almost exclusively in the semiarid West, are especially threatened by the elimination or simplification of woody riparian vegetation. I suggest that riparian vegetation structure and composition, which is associated with avian abundance, species richness, riparian associate bird species, and landscape-level biological diversity, be maintained where possible. Seasonal light (<30% use) fall short-duration grazing seemed to be compatible with the maintenance of woody riparian vegetation whereas summer season-long and summer short-duration grazing is likely incompatible. Close

• 40. [Article] Effects of vegetation and disturbance on fungal communities in the western Cascades of Oregon

  The use of high throughput molecular methods that allow for the study of bacterial communities in environmental samples is commonplace in microbial ecology. Until recently, fungal community ecology has focused ...

  Citation × Citation Citation Abstract Copy Title: Effects of vegetation and disturbance on fungal communities in the western Cascades of Oregon Author: Kageyama, Stacie Ann, 1967- The use of high throughput molecular methods that allow for the study of bacterial communities in environmental samples is commonplace in microbial ecology. Until recently, fungal community ecology has focused on isolation, collection of sporocarps, or collection of ectomycorrhizal roots. The techniques used to extract and amplify DNA from environmental samples are relatively new to the world of fungal community ecology. Many fungi are difficult to isolate. Collection and identification of sporocarps and root tips is time-consuming. Sporocarp production may vary from year-to-year. Here, we present three studies using length heterogeneity PCR (LH-PCR) with the general fungal primers ITS1-F and ITS4 for the internal transcribed spacer region of rRNA to examine changes in fungal community composition in response to changes in vegetation, and disturbance events. In the first study, we used LH-PCR to examine differences in fungal community composition along transects from the forest to the meadow sites at two sites in the western Cascades of Oregon. We found dramatic differences in fungal community composition due to vegetation type and found an intermediate community in the transition zone between meadow and forest. In the second and third studies, we used LH-PCR to identify treatment effects in two manipulative experiments. In both studies, LH-PCR allowed us to observe the changes in community dynamics and identify some of the factors involved in community changes following disturbance. In the second study, we found that fungal succession occurred rapidly when cores were transferred to new environments. We also found evidence that succession occurred more slowly when roots were excluded. In the third study, we used bacterial primers in addition to the fungal ITS primers. We found that presence of live roots rather than either aboveground litter inputs or seasonal differences in sampling times were the greatest determinant of both fungal and bacterial communities at the Detritus Input and Removal Treatment plots 6 years after initiation. Title: Effects of vegetation and disturbance on fungal communities in the western Cascades of Oregon Author: Kageyama, Stacie Ann, 1967- The use of high throughput molecular methods that allow for the study of bacterial communities in environmental samples is commonplace in microbial ecology. Until recently, fungal community ecology has focused on isolation, collection of sporocarps, or collection of ectomycorrhizal roots. The techniques used to extract and amplify DNA from environmental samples are relatively new to the world of fungal community ecology. Many fungi are difficult to isolate. Collection and identification of sporocarps and root tips is time-consuming. Sporocarp production may vary from year-to-year. Here, we present three studies using length heterogeneity PCR (LH-PCR) with the general fungal primers ITS1-F and ITS4 for the internal transcribed spacer region of rRNA to examine changes in fungal community composition in response to changes in vegetation, and disturbance events. In the first study, we used LH-PCR to examine differences in fungal community composition along transects from the forest to the meadow sites at two sites in the western Cascades of Oregon. We found dramatic differences in fungal community composition due to vegetation type and found an intermediate community in the transition zone between meadow and forest. In the second and third studies, we used LH-PCR to identify treatment effects in two manipulative experiments. In both studies, LH-PCR allowed us to observe the changes in community dynamics and identify some of the factors involved in community changes following disturbance. In the second study, we found that fungal succession occurred rapidly when cores were transferred to new environments. We also found evidence that succession occurred more slowly when roots were excluded. In the third study, we used bacterial primers in addition to the fungal ITS primers. We found that presence of live roots rather than either aboveground litter inputs or seasonal differences in sampling times were the greatest determinant of both fungal and bacterial communities at the Detritus Input and Removal Treatment plots 6 years after initiation. Close