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• 21. [Article] The LizLand model : geomorphic landform and surface composition analysis of lizard habitat in the California Mojave Desert

  This dissertation had three main objectives: 1) investigate the role of macro and micro geomorphology in determining lizard distributions in the Southern California Mojave Desert; 2) develop a spatially ...

  Citation × Citation Citation Abstract Copy Title: The LizLand model : geomorphic landform and surface composition analysis of lizard habitat in the California Mojave Desert Author: Heaton, Jill S. This dissertation had three main objectives: 1) investigate the role of macro and micro geomorphology in determining lizard distributions in the Southern California Mojave Desert; 2) develop a spatially explicit lizard habitat model based upon geomorphology; and, 3) determine the interactive effects of geomorphology, roads, and land use in defining lizard habitat. To achieve these objectives a new concept of reptile habitat was developed. Primary field data on presence/absence of lizards in relation to macro and micro geomorphology were collected for three conspicuous and widely distributed Mojave Desert lizard species: Cnemidophorus tigris, Callisaurus draconoides, and Uta stansburiana. Study sites were distributed between the Marine Air Ground Task Force Training Command Marine Corps Air Ground Combat Center (MCAGCC) and Joshua Tree National Park (JOTR) in the Southern California Mojave Desert. Chapter 2 develops a new concept of reptile habitat in and environments. This concept is based upon geomorphic landform and surface composition, which are used to distinguish lizard macro and micro-habitat components. The micro-habitat requirements of individual species are linked to macro geomorphic landforms via their mutual microhabitat characterizations. Chapter 3 describes the development of the spatially explicit LizLand habitat model. LizLand is based on the concept of reptile habitat developed and described in Chapter 2. Digital data used to construct the model include geomorphic landform, surface composition, hydrologic, and elevation data. The model is validated for MCAGCC using secondary species locational data and developed for two additional species for which no primary data were collected. The implications of LizLand for military land management are discussed. The final paper explores in greater depth the relationship between Callisaurus draconoides and the geomorphic landform habitat class alluvial plains. It compares C. draconoides observations on unpaved alluvial plain roads to surrounding habitats and observations between MCAGCC and JOTR. Finally, it considers the use of C. draconoides as an indicator species given its affinity for unpaved alluvial plain roads. Title: The LizLand model : geomorphic landform and surface composition analysis of lizard habitat in the California Mojave Desert Author: Heaton, Jill S. This dissertation had three main objectives: 1) investigate the role of macro and micro geomorphology in determining lizard distributions in the Southern California Mojave Desert; 2) develop a spatially explicit lizard habitat model based upon geomorphology; and, 3) determine the interactive effects of geomorphology, roads, and land use in defining lizard habitat. To achieve these objectives a new concept of reptile habitat was developed. Primary field data on presence/absence of lizards in relation to macro and micro geomorphology were collected for three conspicuous and widely distributed Mojave Desert lizard species: Cnemidophorus tigris, Callisaurus draconoides, and Uta stansburiana. Study sites were distributed between the Marine Air Ground Task Force Training Command Marine Corps Air Ground Combat Center (MCAGCC) and Joshua Tree National Park (JOTR) in the Southern California Mojave Desert. Chapter 2 develops a new concept of reptile habitat in and environments. This concept is based upon geomorphic landform and surface composition, which are used to distinguish lizard macro and micro-habitat components. The micro-habitat requirements of individual species are linked to macro geomorphic landforms via their mutual microhabitat characterizations. Chapter 3 describes the development of the spatially explicit LizLand habitat model. LizLand is based on the concept of reptile habitat developed and described in Chapter 2. Digital data used to construct the model include geomorphic landform, surface composition, hydrologic, and elevation data. The model is validated for MCAGCC using secondary species locational data and developed for two additional species for which no primary data were collected. The implications of LizLand for military land management are discussed. The final paper explores in greater depth the relationship between Callisaurus draconoides and the geomorphic landform habitat class alluvial plains. It compares C. draconoides observations on unpaved alluvial plain roads to surrounding habitats and observations between MCAGCC and JOTR. Finally, it considers the use of C. draconoides as an indicator species given its affinity for unpaved alluvial plain roads. Close

• 22. [Article] Vegetation and soil microbial communities three years after wildfire in spruce-fir forests of northwestern Wyoming

  The Normalized Burn Ratio and Composite Burn Index were used to classify burn severity in three sites that experienced lightning-ignited wildfire in the year 2000. The effect of burn severity (unburned, ...

  Citation × Citation Citation Abstract Copy Title: Vegetation and soil microbial communities three years after wildfire in spruce-fir forests of northwestern Wyoming Author: Hooke, Jennifer Suzanne The Normalized Burn Ratio and Composite Burn Index were used to classify burn severity in three sites that experienced lightning-ignited wildfire in the year 2000. The effect of burn severity (unburned, low, moderate, and high severity classes) was investigated on vegetation and soil microbial community composition. Vegetation communities showed a strong response to burn severity, with distinct communities associated with each burn severity class. Indicator Species Analysis was used to identify plant species associated with each burn severity class; one interesting result from ISA was that trembling aspen (Populus tremuloides) seedlings emerged as an indicator of the moderate severity class. Species richness and tree seedling density differed among burn severity classes. Soil microbial communities were analyzed using Phospholipid Fatty Acid analysis and showed moderate variation among burn severity classes and study sites. Total soil carbon and nitrogen did not differ with burn severity. The C:N ratio, total soil S, and soil pH differed significantly among burn severity classes. While the effect of burn severity is pronounced upon vegetation three years post-fire, effects on soil microbial communities are less evident. This could be attributed to the insulating properties of soils, the time elapsed after fire, or it could be an artifact of the sampling technique. Title: Vegetation and soil microbial communities three years after wildfire in spruce-fir forests of northwestern Wyoming Author: Hooke, Jennifer Suzanne The Normalized Burn Ratio and Composite Burn Index were used to classify burn severity in three sites that experienced lightning-ignited wildfire in the year 2000. The effect of burn severity (unburned, low, moderate, and high severity classes) was investigated on vegetation and soil microbial community composition. Vegetation communities showed a strong response to burn severity, with distinct communities associated with each burn severity class. Indicator Species Analysis was used to identify plant species associated with each burn severity class; one interesting result from ISA was that trembling aspen (Populus tremuloides) seedlings emerged as an indicator of the moderate severity class. Species richness and tree seedling density differed among burn severity classes. Soil microbial communities were analyzed using Phospholipid Fatty Acid analysis and showed moderate variation among burn severity classes and study sites. Total soil carbon and nitrogen did not differ with burn severity. The C:N ratio, total soil S, and soil pH differed significantly among burn severity classes. While the effect of burn severity is pronounced upon vegetation three years post-fire, effects on soil microbial communities are less evident. This could be attributed to the insulating properties of soils, the time elapsed after fire, or it could be an artifact of the sampling technique. Close

• 23. [Article] Classification of oak vegetation in the Willamette Valley

  A plant community classification was developed describing the comprehensive variation of oak vegetation currently occupying the Willamette Valley Ecoregion of western Oregon. Multivariate statistical analyses ...

  Citation × Citation Citation Abstract Copy Title: Classification of oak vegetation in the Willamette Valley Author: Fitzpatrick, Greg, Kertis, Jane, Alverson, Ed, Buechling, Arne A plant community classification was developed describing the comprehensive variation of oak vegetation currently occupying the Willamette Valley Ecoregion of western Oregon. Multivariate statistical analyses were used to classify field collected floristic and habitat data. Field sampling targeted minimally managed, homogenous vegetation stands with a significant oak component occupying at least 0.5 ha. Potential habitat locations were identified from local expert knowledge, data from The Nature Conservancy’s previous conservation planning efforts, and an interpretation of high resolution NAIP imagery. Potential oak habitats were digitized in a GIS and a random selection of sites stratifying significant environmental gradients was generated in order capture the range of oak habitat variability. Precise sample plot locations were predetermined and established at digitized stand centroids. Field sampling was based on relevé plot data collection methods and included ocular estimates of species cover. A total of 350 stands of oak vegetation were sampled over two field seasons. Two-way indicator species analysis (TWINSPAN) was used as an exploratory tool to identify potential patterns in species cover data and Detrended Correspondence Analysis (DCA) was used to delimit final plant community types. Nine vegetation classes were described from ordinations including seven forest / woodland types and two savannas Title: Classification of oak vegetation in the Willamette Valley Author: Fitzpatrick, Greg, Kertis, Jane, Alverson, Ed, Buechling, Arne A plant community classification was developed describing the comprehensive variation of oak vegetation currently occupying the Willamette Valley Ecoregion of western Oregon. Multivariate statistical analyses were used to classify field collected floristic and habitat data. Field sampling targeted minimally managed, homogenous vegetation stands with a significant oak component occupying at least 0.5 ha. Potential habitat locations were identified from local expert knowledge, data from The Nature Conservancy’s previous conservation planning efforts, and an interpretation of high resolution NAIP imagery. Potential oak habitats were digitized in a GIS and a random selection of sites stratifying significant environmental gradients was generated in order capture the range of oak habitat variability. Precise sample plot locations were predetermined and established at digitized stand centroids. Field sampling was based on relevé plot data collection methods and included ocular estimates of species cover. A total of 350 stands of oak vegetation were sampled over two field seasons. Two-way indicator species analysis (TWINSPAN) was used as an exploratory tool to identify potential patterns in species cover data and Detrended Correspondence Analysis (DCA) was used to delimit final plant community types. Nine vegetation classes were described from ordinations including seven forest / woodland types and two savannas Close

• 24. [Article] Estimating Watershed Biodiversity: An Empirical Study of the Chesapeake Bay in Maryland, USA

  There has been increasing demand for rigorous methods for evaluating biodiversity, one of the ecosystem services that sustains and fulfills human life. After carefully examining the literature, we found ...

  Citation × Citation Citation Abstract Copy Title: Estimating Watershed Biodiversity: An Empirical Study of the Chesapeake Bay in Maryland, USA Author: Morimoto, Junko, Voinov, Helena, Wilson, Matthew A., Costanza, Robert Year: 2003 There has been increasing demand for rigorous methods for evaluating biodiversity, one of the ecosystem services that sustains and fulfills human life. After carefully examining the literature, we found three key points that should be taken into account when we evaluate biodiversity. The first point is that any "indicator species" tends to be a leaky target of biodiversity. The second point is that "buffering" that is useful for representing the ecological concept of boundaries should have scientific meanings. The third point is that a "watershed" that integrates most natural processes is advantageous as the spatial range for evaluation. Based on these considerations, we developed the Biodiversity Probability Index (BPI) to account for biodiversity. We analyzed the relationship between BPI and total economic value of ecosystem services per unit area in order to test the reliability and utility of BPI. All BPI values were under a positive regression curve. The curve showed the highest economic value that could be achieved at a given biodiversity status. Based on our findings along the analysis, we conclude that the BPI has two advantages: (1) The BPI identifies the extent of the impact on biodiversity within a given landscape, and its composition of each category of species helps to identify what kind of wild life habitat could be seriously threatened by future land use development; (2) The BPI tells not only the biodiversity condition in ecological sense, but also provides the potential total economic value of ecosystem services, which will be achieved under ideal conditions. Title: Estimating Watershed Biodiversity: An Empirical Study of the Chesapeake Bay in Maryland, USA Author: Morimoto, Junko, Voinov, Helena, Wilson, Matthew A., Costanza, Robert Year: 2003 There has been increasing demand for rigorous methods for evaluating biodiversity, one of the ecosystem services that sustains and fulfills human life. After carefully examining the literature, we found three key points that should be taken into account when we evaluate biodiversity. The first point is that any "indicator species" tends to be a leaky target of biodiversity. The second point is that "buffering" that is useful for representing the ecological concept of boundaries should have scientific meanings. The third point is that a "watershed" that integrates most natural processes is advantageous as the spatial range for evaluation. Based on these considerations, we developed the Biodiversity Probability Index (BPI) to account for biodiversity. We analyzed the relationship between BPI and total economic value of ecosystem services per unit area in order to test the reliability and utility of BPI. All BPI values were under a positive regression curve. The curve showed the highest economic value that could be achieved at a given biodiversity status. Based on our findings along the analysis, we conclude that the BPI has two advantages: (1) The BPI identifies the extent of the impact on biodiversity within a given landscape, and its composition of each category of species helps to identify what kind of wild life habitat could be seriously threatened by future land use development; (2) The BPI tells not only the biodiversity condition in ecological sense, but also provides the potential total economic value of ecosystem services, which will be achieved under ideal conditions. Close

• 25. [Article] Mapping Conservation Opportunity Areas for the Intertwine's Regional Conservation Strategy

  As part of efforts to develop the Regional Conservation Strategy (RCS) for the greater Portland-Vancouver region, Oregon State University’s Institute for Natural Resources (INR) was asked to use spatial ...

  Citation × Citation Citation Abstract Copy Title: Mapping Conservation Opportunity Areas for the Intertwine's Regional Conservation Strategy Author: Burcsu, Theresa, Kagan, James S. Year: 2011 As part of efforts to develop the Regional Conservation Strategy (RCS) for the greater Portland-Vancouver region, Oregon State University’s Institute for Natural Resources (INR) was asked to use spatial modeling to identify conservation opportunity areas (COAs). To complete the project, INR analysts proposed a strategy that would map high value areas using a landscape approach that is focused on relatively high spatial resolution data sets available for the whole metropolitan region. The approach creates 2 main metrics: one focused on terrestrial organisms and the other focused on aquatic and riparian organisms. These are combined to create a map of highly ranked land areas that can be used to formulate a map of conservation opportunity areas. The purpose of the COA mapping project was to use geographic information system methods to identify landscape patches with conservation and restoration potential. The criteria used to identify these high value patches was based on a number of base- and derived-data sets that we call “data inputs.” The data ranged from recently mapped land use and land cover types, hydrological data to indicate species habitat requirements, and road influence on habitat patches. The project identified some areas in which data gaps exist (e.g., region-wide biodiversity data collected and mapped in consistent ways) and some opportunities for improving existent data sets (e.g., land use/land cover map). The project provided several layers that can be used to guide the final Regional Conservation Strategy in selecting conservation opportunity areas. The best layer will depend upon the needs of the RCS efforts, however, in our opinion the most appropriate layer to use is COA 3.11.1 which weights wetlands fairly high, but not as highly as the second data draft. COA 3.10.1 offers similar results as well. Overall it appears that the model results corroborate corridors analysis done previously (Hennings and Soll 2010). There are some issues remaining that we feel can most adequately be addressed by updating the base land use/land cover map. Title: Mapping Conservation Opportunity Areas for the Intertwine's Regional Conservation Strategy Author: Burcsu, Theresa, Kagan, James S. Year: 2011 As part of efforts to develop the Regional Conservation Strategy (RCS) for the greater Portland-Vancouver region, Oregon State University’s Institute for Natural Resources (INR) was asked to use spatial modeling to identify conservation opportunity areas (COAs). To complete the project, INR analysts proposed a strategy that would map high value areas using a landscape approach that is focused on relatively high spatial resolution data sets available for the whole metropolitan region. The approach creates 2 main metrics: one focused on terrestrial organisms and the other focused on aquatic and riparian organisms. These are combined to create a map of highly ranked land areas that can be used to formulate a map of conservation opportunity areas. The purpose of the COA mapping project was to use geographic information system methods to identify landscape patches with conservation and restoration potential. The criteria used to identify these high value patches was based on a number of base- and derived-data sets that we call “data inputs.” The data ranged from recently mapped land use and land cover types, hydrological data to indicate species habitat requirements, and road influence on habitat patches. The project identified some areas in which data gaps exist (e.g., region-wide biodiversity data collected and mapped in consistent ways) and some opportunities for improving existent data sets (e.g., land use/land cover map). The project provided several layers that can be used to guide the final Regional Conservation Strategy in selecting conservation opportunity areas. The best layer will depend upon the needs of the RCS efforts, however, in our opinion the most appropriate layer to use is COA 3.11.1 which weights wetlands fairly high, but not as highly as the second data draft. COA 3.10.1 offers similar results as well. Overall it appears that the model results corroborate corridors analysis done previously (Hennings and Soll 2010). There are some issues remaining that we feel can most adequately be addressed by updating the base land use/land cover map. Close

• 26. [Article] Integration methods for enzymatic analysis response curves which show maxima, minima or inflections

  Integration methods for enzymatic reactions were applied to transducer response vs. time curves which exhibit maxima, minima or inflections. The difference between the integral of the time dependent response ...

  Citation × Citation Citation Abstract Copy Title: Integration methods for enzymatic analysis response curves which show maxima, minima or inflections Author: Radke, Garold E. Integration methods for enzymatic reactions were applied to transducer response vs. time curves which exhibit maxima, minima or inflections. The difference between the integral of the time dependent response and the initial response, often zero, is related to the initial enzyme activity or substrate concentration. Fluorescence response curves which exhibit a maximum due to pre- and postfilter effects at elevated concentrations of a time dependent fluorescence indicator species result in integrals which may not be unique to one analyte concentration. It was found that augmenting the integral data with the time of the maximum permitted correlation of each integral with a unique analyte concentration or enzyme activity. Integrals of response curves which exhibit minima also correlate with unique analyte concentrations. At increased concentration of analyte, however, the minimum may broaden into a minimum plateau and the time of the minimum may supplement the integral data as a more sensitive measure of analyte concentration. Integrals of enzymatic response curves with inflection points correlate with unique analyte concentrations. Integration methods were applied to both real and ideal systems. Theoretical rate equations were used to generate families of idealized response curves exhibiting maxima, minima and inflections. Curves were generated at either fixed initial substrate concentration with variable enzyme activity or at fixed initial enzyme activity with variable substrate concentration. Difference integrals were calculated and plotted as a function of initial substrate concentration or initial enzyme activity. Enzymatic analyses were also performed using systems which produce families of response curves exhibiting maxima, minima and inflections. Difference integrals were calculated for these curves and related to initial enzyme activity or substrate concentration. Title: Integration methods for enzymatic analysis response curves which show maxima, minima or inflections Author: Radke, Garold E. Integration methods for enzymatic reactions were applied to transducer response vs. time curves which exhibit maxima, minima or inflections. The difference between the integral of the time dependent response and the initial response, often zero, is related to the initial enzyme activity or substrate concentration. Fluorescence response curves which exhibit a maximum due to pre- and postfilter effects at elevated concentrations of a time dependent fluorescence indicator species result in integrals which may not be unique to one analyte concentration. It was found that augmenting the integral data with the time of the maximum permitted correlation of each integral with a unique analyte concentration or enzyme activity. Integrals of response curves which exhibit minima also correlate with unique analyte concentrations. At increased concentration of analyte, however, the minimum may broaden into a minimum plateau and the time of the minimum may supplement the integral data as a more sensitive measure of analyte concentration. Integrals of enzymatic response curves with inflection points correlate with unique analyte concentrations. Integration methods were applied to both real and ideal systems. Theoretical rate equations were used to generate families of idealized response curves exhibiting maxima, minima and inflections. Curves were generated at either fixed initial substrate concentration with variable enzyme activity or at fixed initial enzyme activity with variable substrate concentration. Difference integrals were calculated and plotted as a function of initial substrate concentration or initial enzyme activity. Enzymatic analyses were also performed using systems which produce families of response curves exhibiting maxima, minima and inflections. Difference integrals were calculated for these curves and related to initial enzyme activity or substrate concentration. Close

• 27. [Article] Effects of disturbance modes on mycorrhizal fungus communities at Crater Lake National Park

  Crater Lake National Park presents an excellent opportunity for ecological research due to its relatively pristine landscape, the protection of its natural features, its infrastructure, and a Park administration ...

  Citation × Citation Citation Abstract Copy Title: Effects of disturbance modes on mycorrhizal fungus communities at Crater Lake National Park Author: Trappe, Matt Crater Lake National Park presents an excellent opportunity for ecological research due to its relatively pristine landscape, the protection of its natural features, its infrastructure, and a Park administration supportive of scientific inquiry and restoration ecology. The research presented here examines the responses of fungi to various forms of perturbation. In the first chapter, we studied fruiting responses of mycorrhizal fungi to different prescribed applications in a ponderosa pine – white fir ecotype. We found that the most influential factor in fungal fruiting patterns was the soil C:N ratio, and identified corresponding "guilds" of fungal indicator species. Although more intense prescribed burns affected soil attributes, including C:N ratios, the fire served only as a modifier on an underlying landscape pattern of soil attributes. In the second chapter we examined the effects of past and current anthropogenic disturbance on mycorrhizal fungal fruiting patterns in a mountain hemlock – noble fir ecotype. At the microsite scale, intensive use had a detrimental effect on fungal diversity and productivity, but at the scale of the research plots there was no significant effect of anthropogenic disturbance on fungal fruiting patterns. In the third chapter, we studied the effects of the abovementioned disturbance types plus the effects of wildfires on mat-forming soil fungi. We identified 38 taxa of mat-forming fungi, and found that the presence of fungal mats is largely correlated with needle litter. Several of these taxa were not previously known to form mats. Title: Effects of disturbance modes on mycorrhizal fungus communities at Crater Lake National Park Author: Trappe, Matt Crater Lake National Park presents an excellent opportunity for ecological research due to its relatively pristine landscape, the protection of its natural features, its infrastructure, and a Park administration supportive of scientific inquiry and restoration ecology. The research presented here examines the responses of fungi to various forms of perturbation. In the first chapter, we studied fruiting responses of mycorrhizal fungi to different prescribed applications in a ponderosa pine – white fir ecotype. We found that the most influential factor in fungal fruiting patterns was the soil C:N ratio, and identified corresponding "guilds" of fungal indicator species. Although more intense prescribed burns affected soil attributes, including C:N ratios, the fire served only as a modifier on an underlying landscape pattern of soil attributes. In the second chapter we examined the effects of past and current anthropogenic disturbance on mycorrhizal fungal fruiting patterns in a mountain hemlock – noble fir ecotype. At the microsite scale, intensive use had a detrimental effect on fungal diversity and productivity, but at the scale of the research plots there was no significant effect of anthropogenic disturbance on fungal fruiting patterns. In the third chapter, we studied the effects of the abovementioned disturbance types plus the effects of wildfires on mat-forming soil fungi. We identified 38 taxa of mat-forming fungi, and found that the presence of fungal mats is largely correlated with needle litter. Several of these taxa were not previously known to form mats. Close

• 28. [Article] Floodplain vegetation following over 80 years of intensive land use and de-watering : Lower Owens River, California.

  Riparian areas in the arid western United States are critical ecosystems that have been severely degraded by a variety of land and water uses over the last 100 years. In this study, the composition and ...

  Citation × Citation Citation Abstract Copy Title: Floodplain vegetation following over 80 years of intensive land use and de-watering : Lower Owens River, California. Author: Risso, Derek A. Riparian areas in the arid western United States are critical ecosystems that have been severely degraded by a variety of land and water uses over the last 100 years. In this study, the composition and structure of floodplain vegetation along the Lower Owens River in eastern California was quantitatively described following over 80 years of dewatering, grazing, groundwater pumping, and other land uses. The Lower Owens River is a heavily impacted and invaded riparian system which has suffered long-term hydrologic alteration and degrading land use. This study is part of the Lower Owens River Project, an effort to restore ecosystem function to this riverine landscape. Using a stratified design, five 2km long study plots were established in five river reaches within the 86 km study area. Within these plots, dominant species were ranked by cover in six structural classes along 105 line-intercept transects and species canopy cover and ground cover was estimated at 525 2m x 2m sub-plots in 2001 and 2002 to determine vegetation type composition and condition. Twenty–two vegetation types were delineated by cluster analysis and Indicator Species Analysis (ISA). Based on species composition and dominance, cluster analysis and Non-metric Multi-dimensional Scaling (NMS) were employed to examine relationships between vegetation types and environmental parameters. Vegetation composition and species diversity indices were strongly correlated with geographic and hydrologic variables. A weighted wetland indicator index elucidated a shift toward more xeric species and communities in the completely dewatered reaches, as well as a negative correlation with diversity measures. Completely dewatered reaches were dominated by communities that have shifted from native to exotic vegetation types. Five of the 22 distinct vegetation types delineated were dominated by exotic species, mainly salt-cedar (Tamarix spp.) and Russian thistle (Salsola tragus). These communities covered approximately 24% of the study area, and dominated the most severely dewatered reach. Conversely, native communities remained dominant in reaches where surface water was present. Native vegetation types covered 96% of these reaches, an increase of 64% (p=0 from a randomization test) over the severely dewatered reach. The native willow (e.g. Salix goddinggii and Salix exigua) and wet meadow vegetation types exhibited the highest species diversity, and therefore represent target vegetation types for restoration. The results of this study elucidate the changes in vegetation type cover and composition following dewatering and degrading land use in an arid western riparian system. Title: Floodplain vegetation following over 80 years of intensive land use and de-watering : Lower Owens River, California. Author: Risso, Derek A. Riparian areas in the arid western United States are critical ecosystems that have been severely degraded by a variety of land and water uses over the last 100 years. In this study, the composition and structure of floodplain vegetation along the Lower Owens River in eastern California was quantitatively described following over 80 years of dewatering, grazing, groundwater pumping, and other land uses. The Lower Owens River is a heavily impacted and invaded riparian system which has suffered long-term hydrologic alteration and degrading land use. This study is part of the Lower Owens River Project, an effort to restore ecosystem function to this riverine landscape. Using a stratified design, five 2km long study plots were established in five river reaches within the 86 km study area. Within these plots, dominant species were ranked by cover in six structural classes along 105 line-intercept transects and species canopy cover and ground cover was estimated at 525 2m x 2m sub-plots in 2001 and 2002 to determine vegetation type composition and condition. Twenty–two vegetation types were delineated by cluster analysis and Indicator Species Analysis (ISA). Based on species composition and dominance, cluster analysis and Non-metric Multi-dimensional Scaling (NMS) were employed to examine relationships between vegetation types and environmental parameters. Vegetation composition and species diversity indices were strongly correlated with geographic and hydrologic variables. A weighted wetland indicator index elucidated a shift toward more xeric species and communities in the completely dewatered reaches, as well as a negative correlation with diversity measures. Completely dewatered reaches were dominated by communities that have shifted from native to exotic vegetation types. Five of the 22 distinct vegetation types delineated were dominated by exotic species, mainly salt-cedar (Tamarix spp.) and Russian thistle (Salsola tragus). These communities covered approximately 24% of the study area, and dominated the most severely dewatered reach. Conversely, native communities remained dominant in reaches where surface water was present. Native vegetation types covered 96% of these reaches, an increase of 64% (p=0 from a randomization test) over the severely dewatered reach. The native willow (e.g. Salix goddinggii and Salix exigua) and wet meadow vegetation types exhibited the highest species diversity, and therefore represent target vegetation types for restoration. The results of this study elucidate the changes in vegetation type cover and composition following dewatering and degrading land use in an arid western riparian system. Close

• 29. [Article] The Northern Goshawk on the Southern Blue Mountains and Malheur National Forest: A Technical Review of its Status, Ecology and Management

  Technical review / report

  Citation × Citation Citation Abstract Copy Title: The Northern Goshawk on the Southern Blue Mountains and Malheur National Forest: A Technical Review of its Status, Ecology and Management Author: Seager, S Trent, Goodell, John Technical review / report Title: The Northern Goshawk on the Southern Blue Mountains and Malheur National Forest: A Technical Review of its Status, Ecology and Management Author: Seager, S Trent, Goodell, John Technical review / report Close

• 30. [Article] Bird communities in 5- to 34- year old managed Douglas-fir stands on the Willamette National Forest, Oregon Cascades

  Breeding bird communities were examined in 18 managed Douglas-fir stands in 6 age classes from 5 to 34 years old in spring and early summer, 1993 on the Detroit Ranger District, Willamette National Forest, ...

  Citation × Citation Citation Abstract Copy Title: Bird communities in 5- to 34- year old managed Douglas-fir stands on the Willamette National Forest, Oregon Cascades Author: Bettinger, Kelly Anne Breeding bird communities were examined in 18 managed Douglas-fir stands in 6 age classes from 5 to 34 years old in spring and early summer, 1993 on the Detroit Ranger District, Willamette National Forest, Oregon. The range of seral stages included early shrub/sapling, late shrub/sapling, and pole. In general, the 9 younger stands were opencanopy while the 9 older stands were closed-canopy. Of the 50 bird species recorded, 21 had large enough sample sizes for analysis. Of these 21, 8 showed a pattern of increasing abundance with increasing stand age (chestnut-backed chickadee, golden-crowned kinglet, hermit thrush, hermit warbler, Pacific-slope flycatcher, Swainson's thrush, Wilson's warbler, winter wren). Six species showed a pattern of decreasing abundance with increasing stand age (American robin, darkeyed junco, rufous hummingbird, white-crowned sparrow) and 4 species peaked in abundance in age class 2 (10 - 14 years old) before decreasing with increasing stand age (dusky flycatcher, MacGillivray's warbler, orange-crowned warbler, rufous-sided towhee). Two species did not exhibit any particular pattern associated with stand age (warbling vireo, western tanager). Three species were dropped from analysis because their average territory size is larger than the smallest stand surveyed. Abundance indices for species which showed an increasing pattern were positively associated with habitat variables describing conifer basal area, percent cover of live conifer crown between 4 m and the height of the tallest conifer tree, number of conifer stems/ha between 20- and 30- cm dbh, and/or percent cover of live hardwood crown between 4 m and the height of the tallest hardwood tree. Abundance indices for species which showed a decreasing or peaked abundance were negatively associated with the same variables, excluding percent cover of hardwood crown. Total abundance, species richness, and species diversity did not differ (P<0.05) among the age classes. However, bird community composition changed with increasing stand age. Open-canopy stands were dominated by species preferring open-canopy habitats (top 5 species in order of abundance: dark-eyed junco, MacGillivray's warbler, rufous hummingbird, dusky flycatcher, rufous-sided towhee) while closed canopy-stands were dominated by species preferring closed-canopy habitats, (hermit warbler, dark-eyed junco, chestnut-backed chickadee, golden-crowned kinglet, Swainson's thrush); the dark-eyed junco was an exception. The rate of bird community change was rapid along the gradient of open-canopy stands but appeared to reach a plateau once canopy closure was reached. Title: Bird communities in 5- to 34- year old managed Douglas-fir stands on the Willamette National Forest, Oregon Cascades Author: Bettinger, Kelly Anne Breeding bird communities were examined in 18 managed Douglas-fir stands in 6 age classes from 5 to 34 years old in spring and early summer, 1993 on the Detroit Ranger District, Willamette National Forest, Oregon. The range of seral stages included early shrub/sapling, late shrub/sapling, and pole. In general, the 9 younger stands were opencanopy while the 9 older stands were closed-canopy. Of the 50 bird species recorded, 21 had large enough sample sizes for analysis. Of these 21, 8 showed a pattern of increasing abundance with increasing stand age (chestnut-backed chickadee, golden-crowned kinglet, hermit thrush, hermit warbler, Pacific-slope flycatcher, Swainson's thrush, Wilson's warbler, winter wren). Six species showed a pattern of decreasing abundance with increasing stand age (American robin, darkeyed junco, rufous hummingbird, white-crowned sparrow) and 4 species peaked in abundance in age class 2 (10 - 14 years old) before decreasing with increasing stand age (dusky flycatcher, MacGillivray's warbler, orange-crowned warbler, rufous-sided towhee). Two species did not exhibit any particular pattern associated with stand age (warbling vireo, western tanager). Three species were dropped from analysis because their average territory size is larger than the smallest stand surveyed. Abundance indices for species which showed an increasing pattern were positively associated with habitat variables describing conifer basal area, percent cover of live conifer crown between 4 m and the height of the tallest conifer tree, number of conifer stems/ha between 20- and 30- cm dbh, and/or percent cover of live hardwood crown between 4 m and the height of the tallest hardwood tree. Abundance indices for species which showed a decreasing or peaked abundance were negatively associated with the same variables, excluding percent cover of hardwood crown. Total abundance, species richness, and species diversity did not differ (P<0.05) among the age classes. However, bird community composition changed with increasing stand age. Open-canopy stands were dominated by species preferring open-canopy habitats (top 5 species in order of abundance: dark-eyed junco, MacGillivray's warbler, rufous hummingbird, dusky flycatcher, rufous-sided towhee) while closed canopy-stands were dominated by species preferring closed-canopy habitats, (hermit warbler, dark-eyed junco, chestnut-backed chickadee, golden-crowned kinglet, Swainson's thrush); the dark-eyed junco was an exception. The rate of bird community change was rapid along the gradient of open-canopy stands but appeared to reach a plateau once canopy closure was reached. Close