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• 1. [Article] Managing wildlife habitats in forested ecosystems

  Published March 1996. Reprinted August 2006. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Managing wildlife habitats in forested ecosystems Author: Edge, W. Daniel, Oregon State University. Extension Service Published March 1996. Reprinted August 2006. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Managing wildlife habitats in forested ecosystems Author: Edge, W. Daniel, Oregon State University. Extension Service Published March 1996. Reprinted August 2006. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 2. [Article] Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon

  Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the ...

  Citation × Citation Citation Abstract Copy Title: Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon Author: Powers, Breanna F. Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the Willamette Valley, have decreased dramatically due to loss or degradation of habitat. More research is needed on sustaining the populations of butterflies in prairie-oak ecosystems. The purpose of my study was to examine the role prairie-oak habitats have in structuring butterfly communities in the Willamette Valley. My objectives were to: (1) assess how butterfly community structure and species composition (density, abundance, and species richness) varies along an oak canopy cover gradient in order to understand the role of habitat type in structuring butterfly communities in prairie-oak ecosystems; (2) characterize community composition of nectar resources and environmental variables known to be important for butterfly species. I also investigated temporal and structural relationships between butterfly and flower communities. I found that butterfly abundance and density were greater (p < 0.02) in prairies than in oak savannas or oak woodlands; however, species richness did not differ among habitats (p = 0.54). Ordination of prairie-oak habitats in butterfly species space with a joint plot overlay of environmental variables revealed several strong correlations; butterfly community structure was negatively correlated with litter and oak canopy cover and positively correlated to vegetation cover. The prairie, oak savanna, and oak woodland habitat types differed in nectar species community structure, though this difference was small. Non-native species were some of the most abundant flowers species found in all stands. Butterfly communities were positively related to flower communities. I detected significant seasonal patterns among the habitat types in butterfly and flower communities. Prairies appear to be the most important habitat for native butterfly populations compared to oak savanna and oak woodlands. Flowers were most prevalent in prairies and prairies had the highest percentage of native flower species; the prevalence of non-native flower species was greatest in oak woodlands. My study may represent a short-term community transition as a result of management or it may represent a more permanent community. Further study is needed to understand the effects of different management strategies for habitat restoration and the presence of non-native flower species on butterflies in prairie-oak ecosystems in the Willamette Valley. Title: Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon Author: Powers, Breanna F. Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the Willamette Valley, have decreased dramatically due to loss or degradation of habitat. More research is needed on sustaining the populations of butterflies in prairie-oak ecosystems. The purpose of my study was to examine the role prairie-oak habitats have in structuring butterfly communities in the Willamette Valley. My objectives were to: (1) assess how butterfly community structure and species composition (density, abundance, and species richness) varies along an oak canopy cover gradient in order to understand the role of habitat type in structuring butterfly communities in prairie-oak ecosystems; (2) characterize community composition of nectar resources and environmental variables known to be important for butterfly species. I also investigated temporal and structural relationships between butterfly and flower communities. I found that butterfly abundance and density were greater (p < 0.02) in prairies than in oak savannas or oak woodlands; however, species richness did not differ among habitats (p = 0.54). Ordination of prairie-oak habitats in butterfly species space with a joint plot overlay of environmental variables revealed several strong correlations; butterfly community structure was negatively correlated with litter and oak canopy cover and positively correlated to vegetation cover. The prairie, oak savanna, and oak woodland habitat types differed in nectar species community structure, though this difference was small. Non-native species were some of the most abundant flowers species found in all stands. Butterfly communities were positively related to flower communities. I detected significant seasonal patterns among the habitat types in butterfly and flower communities. Prairies appear to be the most important habitat for native butterfly populations compared to oak savanna and oak woodlands. Flowers were most prevalent in prairies and prairies had the highest percentage of native flower species; the prevalence of non-native flower species was greatest in oak woodlands. My study may represent a short-term community transition as a result of management or it may represent a more permanent community. Further study is needed to understand the effects of different management strategies for habitat restoration and the presence of non-native flower species on butterflies in prairie-oak ecosystems in the Willamette Valley. Close

• 3. [Article] Independent effects of habitat loss and fragmentation on pollination : tropical forest fragmentation alters hummingbird movements and pollination dynamics

  A growing body of work reveals that animal-mediated pollination is negatively affected by anthropogenic disturbance. Landscape-scale disturbance results in two often inter-related processes: (1) habitat ...

  Citation × Citation Citation Abstract Copy Title: Independent effects of habitat loss and fragmentation on pollination : tropical forest fragmentation alters hummingbird movements and pollination dynamics Author: Hadley, Adam S. A growing body of work reveals that animal-mediated pollination is negatively affected by anthropogenic disturbance. Landscape-scale disturbance results in two often inter-related processes: (1) habitat loss, and (2) disruptions of habitat configuration (i.e. fragmentation). Understanding the relative effects of such processes is critical in designing effective management strategies to limit pollination and pollinator decline. I reviewed existing published work from 1989 to 2009 and found that only six of 303 studies separated the effects of habitat loss from fragmentation. I provide a synthesis of the current landscape, behavioral, and pollination ecology literature in order to present preliminary multiple working hypotheses to explain how these two landscape processes might independently influence pollination dynamics (Chapter 2). Despite the potential importance of independent effects of habitat fragmentation, effects on pollination remain largely untested. Studies designed to disentangle the independent effects of habitat loss and fragmentation are essential for gaining insight into landscape-mediated pollination declines. I also found that the field of landscape pollination ecology could benefit from quantification of the matrix, landscape functional connectivity, and pollinator movement behavior. To test the hypothesis that pollinator movement can be influenced by landscape configuration, I translocated radio-tagged hummingbirds across agricultural and forested landscapes near Las Cruces, Costa Rica (Chapter 3). I found return paths were on average more direct in forested than in agricultural landscapes. In addition, movement paths chosen in agricultural landscapes were more forested than the most direct route suggesting that hummingbirds avoided crossing open areas when possible. To determine if differences in pollinator movement translated to differences in plant reproduction, I tested the relative importance of landscape composition versus configuration on the reproductive success of Heliconia tortuosa, a hummingbird-pollinated forest herb (Chapter 4). I used a stratified random sampling design to select sites across orthogonal gradients in patch size, amount of forest, and elevation. I tested four landscape change hypotheses (i.e., local, landscape composition, landscape fragmentation, and fragmentation threshold). I found that Heliconia reproduction supported both the local site and landscape fragmentation hypotheses. Seed set increased with increasing forest patch size independent of amount of forest in the surrounding landscape. I also found that increasing patch size positively influenced the relative abundance of pollinators. The observed differences in seed set likely resulted from differences in hummingbird movements (Chapter 3) and/or abundance under different landscape configurations. Title: Independent effects of habitat loss and fragmentation on pollination : tropical forest fragmentation alters hummingbird movements and pollination dynamics Author: Hadley, Adam S. A growing body of work reveals that animal-mediated pollination is negatively affected by anthropogenic disturbance. Landscape-scale disturbance results in two often inter-related processes: (1) habitat loss, and (2) disruptions of habitat configuration (i.e. fragmentation). Understanding the relative effects of such processes is critical in designing effective management strategies to limit pollination and pollinator decline. I reviewed existing published work from 1989 to 2009 and found that only six of 303 studies separated the effects of habitat loss from fragmentation. I provide a synthesis of the current landscape, behavioral, and pollination ecology literature in order to present preliminary multiple working hypotheses to explain how these two landscape processes might independently influence pollination dynamics (Chapter 2). Despite the potential importance of independent effects of habitat fragmentation, effects on pollination remain largely untested. Studies designed to disentangle the independent effects of habitat loss and fragmentation are essential for gaining insight into landscape-mediated pollination declines. I also found that the field of landscape pollination ecology could benefit from quantification of the matrix, landscape functional connectivity, and pollinator movement behavior. To test the hypothesis that pollinator movement can be influenced by landscape configuration, I translocated radio-tagged hummingbirds across agricultural and forested landscapes near Las Cruces, Costa Rica (Chapter 3). I found return paths were on average more direct in forested than in agricultural landscapes. In addition, movement paths chosen in agricultural landscapes were more forested than the most direct route suggesting that hummingbirds avoided crossing open areas when possible. To determine if differences in pollinator movement translated to differences in plant reproduction, I tested the relative importance of landscape composition versus configuration on the reproductive success of Heliconia tortuosa, a hummingbird-pollinated forest herb (Chapter 4). I used a stratified random sampling design to select sites across orthogonal gradients in patch size, amount of forest, and elevation. I tested four landscape change hypotheses (i.e., local, landscape composition, landscape fragmentation, and fragmentation threshold). I found that Heliconia reproduction supported both the local site and landscape fragmentation hypotheses. Seed set increased with increasing forest patch size independent of amount of forest in the surrounding landscape. I also found that increasing patch size positively influenced the relative abundance of pollinators. The observed differences in seed set likely resulted from differences in hummingbird movements (Chapter 3) and/or abundance under different landscape configurations. Close

• 4. [Article] Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica

  Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, ...

  Citation × Citation Citation Abstract Copy Title: Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica Author: Volpe, Noelia L. Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, may also negatively affect biodiversity for those species that exhibit behavioral responses to changes in habitat configuration. Such behavioral changes include movement, which is influenced by subdividing and isolating habitats through which animals prefer to travel. Ecosystem services that depend on the ability of animals to move through the landscape could be affected by changes in habitat configuration. Pollination is one such process because access of pollinators to flowers is often the key determinant of plant reproductive success. Yet, relatively little is known about how forest fragmentation may influence the flow of pollen carried by forest-dwelling pollinators, such as hummingbirds. I evaluate how changes in the distribution of pollinators produced by habitat fragmentation in southern Costa Rica affects a pollination web occupied by a generalist tropical pollinator, the green hermit hummingbird (Phaethornis guy). I used radio-telemetry to measure patterns of space use by green hermits living in forested areas with different levels of fragmentation. I first characterize patterns of space use by green hermits at three scales: point, path and home range. I found that green hermits have marked preference for locations in forested areas with high density of Heliconia plants and canopy cover; prefer paths close to streams that minimize crossing large stretches of non-forested matrix; and establish their home ranges in areas with high forest amount. In addition, home range area was negatively related to the amount of forest within it and positively related to fragmentation per se. Average resource density within the home range appeared to be unrelated to the area covered by the green hermits. My observations indicate that while the presence of green hermits in an area is mainly determined by the amount of forest available, the way they move through a landscape will be strongly affected by habitat configuration. In this context, pollen transfer by green hermits will be limited by the presence of open, non-forested areas owing to matrix avoidance. In landscapes with small discontinuous patches, the total area covered by an individual green hermit is likely to be small so I hypothesize that the genetic variability of pollen it transports may be diminished. I also assess the effectiveness of a tool commonly used to study the effect of habitat fragmentation on animal movement: translocation experiments. Such experiments are purported to have important advantages of being time efficient and standardizing across individuals the ‘motivation’ to move. Yet, we lack tests of whether movement behavior of translocated birds reflects natural behavior of unmanipulated birds. I compared the routine movement behavior of green hermits to that of experimentally translocated individuals. Behaviors documented during translocation experiments reflected those observed during routine movements. Both translocated and non-translocated birds showed similar levels of preference for mature tropical forest at the point level and avoided moving across non-forested matrix while selecting streams as movement corridors at the path level. Movement rates (distance covered per unit time) were generally higher during translocation experiments. However, the negative influence of forest cover on movement rates was proportionately similar in translocation and routine movement treatments. My results show that movement behavior of birds during translocation experiments is similar to natural movement behavior of birds. Therefore, translocation experiments may be reliable tools to address effects of landscape structure on animal movement. Title: Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica Author: Volpe, Noelia L. Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, may also negatively affect biodiversity for those species that exhibit behavioral responses to changes in habitat configuration. Such behavioral changes include movement, which is influenced by subdividing and isolating habitats through which animals prefer to travel. Ecosystem services that depend on the ability of animals to move through the landscape could be affected by changes in habitat configuration. Pollination is one such process because access of pollinators to flowers is often the key determinant of plant reproductive success. Yet, relatively little is known about how forest fragmentation may influence the flow of pollen carried by forest-dwelling pollinators, such as hummingbirds. I evaluate how changes in the distribution of pollinators produced by habitat fragmentation in southern Costa Rica affects a pollination web occupied by a generalist tropical pollinator, the green hermit hummingbird (Phaethornis guy). I used radio-telemetry to measure patterns of space use by green hermits living in forested areas with different levels of fragmentation. I first characterize patterns of space use by green hermits at three scales: point, path and home range. I found that green hermits have marked preference for locations in forested areas with high density of Heliconia plants and canopy cover; prefer paths close to streams that minimize crossing large stretches of non-forested matrix; and establish their home ranges in areas with high forest amount. In addition, home range area was negatively related to the amount of forest within it and positively related to fragmentation per se. Average resource density within the home range appeared to be unrelated to the area covered by the green hermits. My observations indicate that while the presence of green hermits in an area is mainly determined by the amount of forest available, the way they move through a landscape will be strongly affected by habitat configuration. In this context, pollen transfer by green hermits will be limited by the presence of open, non-forested areas owing to matrix avoidance. In landscapes with small discontinuous patches, the total area covered by an individual green hermit is likely to be small so I hypothesize that the genetic variability of pollen it transports may be diminished. I also assess the effectiveness of a tool commonly used to study the effect of habitat fragmentation on animal movement: translocation experiments. Such experiments are purported to have important advantages of being time efficient and standardizing across individuals the ‘motivation’ to move. Yet, we lack tests of whether movement behavior of translocated birds reflects natural behavior of unmanipulated birds. I compared the routine movement behavior of green hermits to that of experimentally translocated individuals. Behaviors documented during translocation experiments reflected those observed during routine movements. Both translocated and non-translocated birds showed similar levels of preference for mature tropical forest at the point level and avoided moving across non-forested matrix while selecting streams as movement corridors at the path level. Movement rates (distance covered per unit time) were generally higher during translocation experiments. However, the negative influence of forest cover on movement rates was proportionately similar in translocation and routine movement treatments. My results show that movement behavior of birds during translocation experiments is similar to natural movement behavior of birds. Therefore, translocation experiments may be reliable tools to address effects of landscape structure on animal movement. Close

• 5. [Article] Interactions between ecosystem nitrogen and bedrock control long-term calcium sources in Oregon Coast Range forests

  Ecosystem nitrogen (N) supply strongly influences the availability and cycling of other essential nutrients in temperate forests, especially calcium (Ca). Short-term additions of N that exceed ecosystem ...

  Citation × Citation Citation Abstract Copy Title: Interactions between ecosystem nitrogen and bedrock control long-term calcium sources in Oregon Coast Range forests Author: Hynicka, Justin D. Ecosystem nitrogen (N) supply strongly influences the availability and cycling of other essential nutrients in temperate forests, especially calcium (Ca). Short-term additions of N that exceed ecosystem demands often increase dissolved nitrate fluxes and decrease soil pH, which can stimulate soil Ca loss. However, the long-term effects of high N supply on ecosystem Ca availability are more difficult to determine, and may depend on the Ca content of bedrock and mineral soils. To address this, we examined major and trace element concentrations and ⁸⁷Sr/⁸⁶Sr ratios that trace Ca sources in precipitation, foliage, soil pools, and bedrock at 24 forested sites in the Oregon Coast Range having a wide, natural range of soil N (0.16 - 0.97 % N, 0-10 cm) on contrasting basaltic and sedimentary bedrock. Using a suite of 17 site properties, we also evaluated whether soil N variation across sites was related to the five major state-factors of soil and ecosystem development: climate, organisms, topography, parent material, and time. We found that as soil N increased across sites, its ¹⁵N/¹⁴N ratio declined towards atmospheric values, suggesting that soil N variation reflects a biotic legacy of symbiotic N fixation inputs. In contrast, soil N variation was unrelated to 17 other metrics of soil forming factors that represented climate (mean annual precipitation, mean annual temperature, and distance from the coast), topography (slope, soil depth, and abundance of coarse rock fragments), parent material (within bedrock type bulk and 1 M HNO₃ leachable rock Ca chemistry), and proxies of soil age (Hurst's redness rating, effective cation exchange capacity, Ca in non-exchangeable soil residues, chemical index of alteration, weathering index of Parker, Ca in coarse soil fragments, and soil Ca loss relative to bedrock). These analyses highlight symbiotic N-fixing red alder as a keystone organismal state-factor that produces a wide range of soil N accumulation in coastal Oregon forests. Strontium isotopes (⁸⁷Sr/⁸⁶Sr) and other geochemical analyses indicate that long-term Ca sources in foliage and exchangeable soil pools in Oregon Coast Range forests depend on an interactive effect between N availability and bedrock. Basaltic rocks contained nearly 20-times more Ca than sedimentary rocks across our sites, and this difference was reflected in Sr-isotope partitioning of base cation sources. Atmospheric sources dominated plant and soil pools in forests overlying Ca-poor sedimentary rock, regardless of variation in soil N, indicating extremely limited capacity of weathering to support forest Ca demands. In contrast, forests overlying basaltic rock obtained as much as 80% of Ca from rock weathering in low N sites, yet relied to a greater extent on atmospheric Ca as soil N increased, with less than 10% of Ca from rock weathering at sites with the highest soil N. Surprisingly, differences in fresh rock Ca content and base cation sources between sedimentary and basaltic sites was not reflected in ecosystem Ca availability, and instead increasing soil N caused similar declines in foliar and exchangeable Ca across both rock types. This illustrates that nutrient pool sizes do not necessarily reflect long-term nutrient supply, and highlights how coupled biogeochemical cycles within ecosystems can regulate nutrient loss and supply to biota. Broadly, our results highlight how interactions between biological and geologic factors can influence base cation sources in forest ecosystems. The sustainability of base cation supplies to forests may therefore depend greatly on variation in bedrock weathering at low N sites, yet converge to depend on atmospheric inputs in sites that receive high N loading from biological fixation or anthropogenic deposition. Title: Interactions between ecosystem nitrogen and bedrock control long-term calcium sources in Oregon Coast Range forests Author: Hynicka, Justin D. Ecosystem nitrogen (N) supply strongly influences the availability and cycling of other essential nutrients in temperate forests, especially calcium (Ca). Short-term additions of N that exceed ecosystem demands often increase dissolved nitrate fluxes and decrease soil pH, which can stimulate soil Ca loss. However, the long-term effects of high N supply on ecosystem Ca availability are more difficult to determine, and may depend on the Ca content of bedrock and mineral soils. To address this, we examined major and trace element concentrations and ⁸⁷Sr/⁸⁶Sr ratios that trace Ca sources in precipitation, foliage, soil pools, and bedrock at 24 forested sites in the Oregon Coast Range having a wide, natural range of soil N (0.16 - 0.97 % N, 0-10 cm) on contrasting basaltic and sedimentary bedrock. Using a suite of 17 site properties, we also evaluated whether soil N variation across sites was related to the five major state-factors of soil and ecosystem development: climate, organisms, topography, parent material, and time. We found that as soil N increased across sites, its ¹⁵N/¹⁴N ratio declined towards atmospheric values, suggesting that soil N variation reflects a biotic legacy of symbiotic N fixation inputs. In contrast, soil N variation was unrelated to 17 other metrics of soil forming factors that represented climate (mean annual precipitation, mean annual temperature, and distance from the coast), topography (slope, soil depth, and abundance of coarse rock fragments), parent material (within bedrock type bulk and 1 M HNO₃ leachable rock Ca chemistry), and proxies of soil age (Hurst's redness rating, effective cation exchange capacity, Ca in non-exchangeable soil residues, chemical index of alteration, weathering index of Parker, Ca in coarse soil fragments, and soil Ca loss relative to bedrock). These analyses highlight symbiotic N-fixing red alder as a keystone organismal state-factor that produces a wide range of soil N accumulation in coastal Oregon forests. Strontium isotopes (⁸⁷Sr/⁸⁶Sr) and other geochemical analyses indicate that long-term Ca sources in foliage and exchangeable soil pools in Oregon Coast Range forests depend on an interactive effect between N availability and bedrock. Basaltic rocks contained nearly 20-times more Ca than sedimentary rocks across our sites, and this difference was reflected in Sr-isotope partitioning of base cation sources. Atmospheric sources dominated plant and soil pools in forests overlying Ca-poor sedimentary rock, regardless of variation in soil N, indicating extremely limited capacity of weathering to support forest Ca demands. In contrast, forests overlying basaltic rock obtained as much as 80% of Ca from rock weathering in low N sites, yet relied to a greater extent on atmospheric Ca as soil N increased, with less than 10% of Ca from rock weathering at sites with the highest soil N. Surprisingly, differences in fresh rock Ca content and base cation sources between sedimentary and basaltic sites was not reflected in ecosystem Ca availability, and instead increasing soil N caused similar declines in foliar and exchangeable Ca across both rock types. This illustrates that nutrient pool sizes do not necessarily reflect long-term nutrient supply, and highlights how coupled biogeochemical cycles within ecosystems can regulate nutrient loss and supply to biota. Broadly, our results highlight how interactions between biological and geologic factors can influence base cation sources in forest ecosystems. The sustainability of base cation supplies to forests may therefore depend greatly on variation in bedrock weathering at low N sites, yet converge to depend on atmospheric inputs in sites that receive high N loading from biological fixation or anthropogenic deposition. Close

• 6. [Article] Predicting global change effects on forest biomass and composition in south-central Siberia

  Multiple global changes such as timber harvesting in areas not previously disturbed by cutting and climate change will undoubtedly affect the composition and spatial distribution of boreal forests, which ...

  Citation × Citation Citation Abstract Copy Title: Predicting global change effects on forest biomass and composition in south-central Siberia Author: Gustafson, Eric J., Shvidenko, Anatoly Z., Sturtevant, Brian R., Scheller, Robert M. Year: 2010 Multiple global changes such as timber harvesting in areas not previously disturbed by cutting and climate change will undoubtedly affect the composition and spatial distribution of boreal forests, which will, in turn, affect the ability of these forests to retain carbon and maintain biodiversity. To predict future states of the boreal forest reliably, it is necessary to understand the complex interactions among forest regenerative processes (succession), natural disturbances (e.g., fire, wind, and insects), and anthropogenic disturbances (e.g., timber harvest). We used a landscape succession and disturbance model (LANDIS-II) to study the relative effects of climate change, timber harvesting, and insect outbreaks on forest composition, biomass (carbon), and landscape pattern in south-central Siberia. We found that most response variables were more strongly influenced by timber harvest and insect outbreaks than by the direct effects of climate change. Direct climate effects generally increased tree productivity and modified probability of establishment, but indirect effects on the fire regime generally counteracted the direct effects of climate on forest composition. Harvest and insects significantly changed forest composition, reduced living aboveground biomass, and increased forest fragmentation. We concluded that: (1) Global change is likely to significantly change forest composition of south-central Siberian landscapes, with some changes taking ecosystems outside the historic range of variability. (2) The direct effects of climate change in the study area are not as significant as the exploitation of virgin forest by timber harvest and the potential increased outbreaks of the Siberian silk moth. (3) Novel disturbance by timber harvest and insect outbreaks may greatly reduce the aboveground living biomass of Siberian forests and may significantly alter ecosystem dynamics and wildlife populations by increasing forest fragmentation. Title: Predicting global change effects on forest biomass and composition in south-central Siberia Author: Gustafson, Eric J., Shvidenko, Anatoly Z., Sturtevant, Brian R., Scheller, Robert M. Year: 2010 Multiple global changes such as timber harvesting in areas not previously disturbed by cutting and climate change will undoubtedly affect the composition and spatial distribution of boreal forests, which will, in turn, affect the ability of these forests to retain carbon and maintain biodiversity. To predict future states of the boreal forest reliably, it is necessary to understand the complex interactions among forest regenerative processes (succession), natural disturbances (e.g., fire, wind, and insects), and anthropogenic disturbances (e.g., timber harvest). We used a landscape succession and disturbance model (LANDIS-II) to study the relative effects of climate change, timber harvesting, and insect outbreaks on forest composition, biomass (carbon), and landscape pattern in south-central Siberia. We found that most response variables were more strongly influenced by timber harvest and insect outbreaks than by the direct effects of climate change. Direct climate effects generally increased tree productivity and modified probability of establishment, but indirect effects on the fire regime generally counteracted the direct effects of climate on forest composition. Harvest and insects significantly changed forest composition, reduced living aboveground biomass, and increased forest fragmentation. We concluded that: (1) Global change is likely to significantly change forest composition of south-central Siberian landscapes, with some changes taking ecosystems outside the historic range of variability. (2) The direct effects of climate change in the study area are not as significant as the exploitation of virgin forest by timber harvest and the potential increased outbreaks of the Siberian silk moth. (3) Novel disturbance by timber harvest and insect outbreaks may greatly reduce the aboveground living biomass of Siberian forests and may significantly alter ecosystem dynamics and wildlife populations by increasing forest fragmentation. Close

• 7. [Article] Managing for Ecosystem Services through Governance Networks: An Analysis of Oregon Senate Bill 513

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Managing for Ecosystem Services through Governance Networks: An Analysis of Oregon Senate Bill 513 Author: Paulsen, Harmony Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Managing for Ecosystem Services through Governance Networks: An Analysis of Oregon Senate Bill 513 Author: Paulsen, Harmony Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 8. [Article] The Rise of the Mesopredator

  Apex predators have experienced catastrophic declines throughout the world as a result of human persecution and habitat loss. These collapses in top predator populations are commonly associated with dramatic ...

  Citation × Citation Citation Abstract Copy Title: The Rise of the Mesopredator Author: Stoner, Chantal J., Brashares, Justin S., Bean, William T., Prugh, Laura R., Epps, Clinton W., Laliberte, Andrea S., Ripple, William J. Apex predators have experienced catastrophic declines throughout the world as a result of human persecution and habitat loss. These collapses in top predator populations are commonly associated with dramatic increases in the abundance of smaller predators. Known as “mesopredator release,” this trophic interaction has been recorded across a range of communities and ecosystems. Mesopredator outbreaks often lead to declining prey populations, sometimes destabilizing communities and driving local extinctions.We present an overview of mesopredator release and illustrate how its underlying concepts can be used to improve predator management in an increasingly fragmented world. We also examine shifts in North American carnivore ranges during the past 200 years and show that 60% of mesopredator ranges have expanded, whereas all apex predator ranges have contracted. The need to understand how best to predict and manage mesopredator release is urgent—mesopredator outbreaks are causing high ecological, economic, and social costs around the world. Title: The Rise of the Mesopredator Author: Stoner, Chantal J., Brashares, Justin S., Bean, William T., Prugh, Laura R., Epps, Clinton W., Laliberte, Andrea S., Ripple, William J. Apex predators have experienced catastrophic declines throughout the world as a result of human persecution and habitat loss. These collapses in top predator populations are commonly associated with dramatic increases in the abundance of smaller predators. Known as “mesopredator release,” this trophic interaction has been recorded across a range of communities and ecosystems. Mesopredator outbreaks often lead to declining prey populations, sometimes destabilizing communities and driving local extinctions.We present an overview of mesopredator release and illustrate how its underlying concepts can be used to improve predator management in an increasingly fragmented world. We also examine shifts in North American carnivore ranges during the past 200 years and show that 60% of mesopredator ranges have expanded, whereas all apex predator ranges have contracted. The need to understand how best to predict and manage mesopredator release is urgent—mesopredator outbreaks are causing high ecological, economic, and social costs around the world. Close

• 9. [Article] Community profiles of ammonia oxidizers across high-elevation forest-to-meadow transects

  In recent years considerable interest has been shown in the diversity of ammonia-oxidizing bacteria in soil communities. The majority of the research has been carried out in Northern Europe where soils ...

  Citation × Citation Citation Abstract Copy Title: Community profiles of ammonia oxidizers across high-elevation forest-to-meadow transects Author: Mintie, Ann In recent years considerable interest has been shown in the diversity of ammonia-oxidizing bacteria in soil communities. The majority of the research has been carried out in Northern Europe where soils have received high atmospheric inputs of nitrogen over the past two centuries. In contrast, although much work has been conducted on nitrogen cycling processes in nitrogen limited forest ecosystems in western North America, no studies have examined the characteristics of ammonia-oxidizing communities in those environments. I was interested in measuring nitrification potential along a high-elevation temperate meadow-to-forest gradient, and characterizing the ammonia-oxidizing communities along that gradient using both molecular and culturing methods. Two experimental sites (Lookout and Carpenter) were chosen in the H.J. Andrews Experimental Forest, located in the western Cascade Range of Oregon, at elevations of approximately 1500 meters. Although nitrification potential rates (NPRs) between sites were not significantly different (P=0.544), variation was observed both within and between sites for specific vegetation types. NPRs were significantly lower in forest (F) soil samples than in meadow (M) soil samples, averaging 5 and 2% of meadow NPRs at Lookout and Carpenter, respectively. In meadow soil samples, most probable number (MPN) population densities of ammonia-oxidizers ranged from 0.6 to 2.6 x 10⁴ cells gram⁻¹ of oven dry soil and 0.9 x 10³ to 1.1 x 10⁵ cells g⁻¹ OD soil at Lookout and Carpenter, respectively. In forest soil samples, population densities ranged from undetectable to 1.1 x 10⁴ cells g⁻¹ OD soil, and 0.9 x 10² to 2.3 x 10³ cells g⁻¹ OD soil at Lookout and Carpenter, respectively. Microbial community DNA was amplified using primers to the ammonia monooxygenase subunit A. Terminal restriction fragments polymorphism analysis with three different restriction enzymes (CfoI, TaqI, and AluI) revealed community profiles dominated by Nitrosospira species. One fragment from CfoI (66 bp) and one fragment from AluI (392-bp) were prominent in 47 soil samples from both sites, and represented between 32 to 100% of the Genescan fragment analyses of PCR products. A full length fragment from AluI digests (491-bp), and three fragments from CfoI (68, 100, and 135- bp) were found sporadically in fewer soil sample T-RFLPs, and within those samples represented smaller percentages of total peak areas. The CfoI 135-bp fragment length was associated primarily with M and meadow/forest (M/F) soils where it was observed in approximately 58 and 100% of the respective transect locations. Eight isolates recovered from soil samples were analyzed using the same molecular methods as the field samples. The T-RFLP patterns of the isolates corresponded with many of those found in the community fingerprints. Four unique amoA sequences were identified among these isolates, including one that possessed the dominant T-RFLP amoA fingerprint in soil samples. This sequence shared 99.8% similarity with Nitrosospira sp. Ka4, a cluster 4 ammonia oxidizer isolated in Norway. Sequence analysis phylogenetically associated the other three isolates (with unique amoA sequences) near Nitrosospira sp. Nsp 1 and Nitrosospira briensis, both cluster 3 ammonia oxidizers. Cloning and sequencing of soil DNA confirmed that ammonia oxidizers with these amoA sequences were present in the soil samples. Two additional amoA sequences were identified in clones that were 95% similar and paraphylogenetically positioned between representatives of clusters 3 and 4. So far, these sequences have not been found in any of the isolates analyzed. Title: Community profiles of ammonia oxidizers across high-elevation forest-to-meadow transects Author: Mintie, Ann In recent years considerable interest has been shown in the diversity of ammonia-oxidizing bacteria in soil communities. The majority of the research has been carried out in Northern Europe where soils have received high atmospheric inputs of nitrogen over the past two centuries. In contrast, although much work has been conducted on nitrogen cycling processes in nitrogen limited forest ecosystems in western North America, no studies have examined the characteristics of ammonia-oxidizing communities in those environments. I was interested in measuring nitrification potential along a high-elevation temperate meadow-to-forest gradient, and characterizing the ammonia-oxidizing communities along that gradient using both molecular and culturing methods. Two experimental sites (Lookout and Carpenter) were chosen in the H.J. Andrews Experimental Forest, located in the western Cascade Range of Oregon, at elevations of approximately 1500 meters. Although nitrification potential rates (NPRs) between sites were not significantly different (P=0.544), variation was observed both within and between sites for specific vegetation types. NPRs were significantly lower in forest (F) soil samples than in meadow (M) soil samples, averaging 5 and 2% of meadow NPRs at Lookout and Carpenter, respectively. In meadow soil samples, most probable number (MPN) population densities of ammonia-oxidizers ranged from 0.6 to 2.6 x 10⁴ cells gram⁻¹ of oven dry soil and 0.9 x 10³ to 1.1 x 10⁵ cells g⁻¹ OD soil at Lookout and Carpenter, respectively. In forest soil samples, population densities ranged from undetectable to 1.1 x 10⁴ cells g⁻¹ OD soil, and 0.9 x 10² to 2.3 x 10³ cells g⁻¹ OD soil at Lookout and Carpenter, respectively. Microbial community DNA was amplified using primers to the ammonia monooxygenase subunit A. Terminal restriction fragments polymorphism analysis with three different restriction enzymes (CfoI, TaqI, and AluI) revealed community profiles dominated by Nitrosospira species. One fragment from CfoI (66 bp) and one fragment from AluI (392-bp) were prominent in 47 soil samples from both sites, and represented between 32 to 100% of the Genescan fragment analyses of PCR products. A full length fragment from AluI digests (491-bp), and three fragments from CfoI (68, 100, and 135- bp) were found sporadically in fewer soil sample T-RFLPs, and within those samples represented smaller percentages of total peak areas. The CfoI 135-bp fragment length was associated primarily with M and meadow/forest (M/F) soils where it was observed in approximately 58 and 100% of the respective transect locations. Eight isolates recovered from soil samples were analyzed using the same molecular methods as the field samples. The T-RFLP patterns of the isolates corresponded with many of those found in the community fingerprints. Four unique amoA sequences were identified among these isolates, including one that possessed the dominant T-RFLP amoA fingerprint in soil samples. This sequence shared 99.8% similarity with Nitrosospira sp. Ka4, a cluster 4 ammonia oxidizer isolated in Norway. Sequence analysis phylogenetically associated the other three isolates (with unique amoA sequences) near Nitrosospira sp. Nsp 1 and Nitrosospira briensis, both cluster 3 ammonia oxidizers. Cloning and sequencing of soil DNA confirmed that ammonia oxidizers with these amoA sequences were present in the soil samples. Two additional amoA sequences were identified in clones that were 95% similar and paraphylogenetically positioned between representatives of clusters 3 and 4. So far, these sequences have not been found in any of the isolates analyzed. Close

• 10. [Article] Human effects on ecological connectivity in aquatic ecosystems: Integrating scientific approaches to support management and mitigation

  This is an 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/science-of-the-t...

  Citation × Citation Citation Abstract Copy Title: Human effects on ecological connectivity in aquatic ecosystems: Integrating scientific approaches to support management and mitigation Author: Riginos, Cynthia, Nagelkerken, Ivan, Finn, Debra S., Hughes, Jane M., Harrod, Chris, Crook, David A., Jennings, Simon, Gillanders, Bronwyn M., Hansen, Michael M., Fry, Brian, Kilada, Raouf W., Erős, Tibor, Allendorf, Frederick W., Hermoso, Virgilio, Page, Timothy J., Hadwen, Wade L., Lowe, Winsor H. This is an 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/science-of-the-total-environment/ Title: Human effects on ecological connectivity in aquatic ecosystems: Integrating scientific approaches to support management and mitigation Author: Riginos, Cynthia, Nagelkerken, Ivan, Finn, Debra S., Hughes, Jane M., Harrod, Chris, Crook, David A., Jennings, Simon, Gillanders, Bronwyn M., Hansen, Michael M., Fry, Brian, Kilada, Raouf W., Erős, Tibor, Allendorf, Frederick W., Hermoso, Virgilio, Page, Timothy J., Hadwen, Wade L., Lowe, Winsor H. This is an 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/science-of-the-total-environment/ Close