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• 1. [Article] Stratigraphy and sedimentation of the Spencer Formation in Yamhill and Washington counties, Oregon

  The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphy and sedimentation of the Spencer Formation in Yamhill and Washington counties, Oregon Author: Al-Azzaby, Fathi Ayoub Year: 1980 The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely of sandstone with interbedded thin layers of mudstone in the uppermost member. The sedimentary structure and paleoecology indicate a shallow marine depositional environment. The upper member of the Spencer Formation contains more quartz, plagioclase, and hornblende than does the lower member, but K-feldspar is less than that of the lower member. Shallower water conditions for the deposition of the upper member are indicated by sedimentary structures and the abundance of pebbly lenses and coaly material. Eighteen species of megafossils collected from the formation indicate that the Spencer Formation is of the Tejon stage (late Eocene of the West Coast). Title: Stratigraphy and sedimentation of the Spencer Formation in Yamhill and Washington counties, Oregon Author: Al-Azzaby, Fathi Ayoub Year: 1980 The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely of sandstone with interbedded thin layers of mudstone in the uppermost member. The sedimentary structure and paleoecology indicate a shallow marine depositional environment. The upper member of the Spencer Formation contains more quartz, plagioclase, and hornblende than does the lower member, but K-feldspar is less than that of the lower member. Shallower water conditions for the deposition of the upper member are indicated by sedimentary structures and the abundance of pebbly lenses and coaly material. Eighteen species of megafossils collected from the formation indicate that the Spencer Formation is of the Tejon stage (late Eocene of the West Coast). Close

• 2. [Article] Ecological subsidies to rocky intertidal communities: Linear or non-linear changes along a consistent geographic upwelling transition?

  This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-experimental-marine-biology-and-ecology/. To the best ...

  Citation × Citation Citation Abstract Copy Title: Ecological subsidies to rocky intertidal communities: Linear or non-linear changes along a consistent geographic upwelling transition? Author: Menge, Bruce A., Nielsen, Karina J., Chan, Francis, Lubchenco, Jane, Freidenburg, Tess L., Krenz, Christopher, Foley, Melissa M. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-experimental-marine-biology-and-ecology/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Ecological subsidies to rocky intertidal communities: Linear or non-linear changes along a consistent geographic upwelling transition? Author: Menge, Bruce A., Nielsen, Karina J., Chan, Francis, Lubchenco, Jane, Freidenburg, Tess L., Krenz, Christopher, Foley, Melissa M. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-experimental-marine-biology-and-ecology/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 3. [Article] Comparative hazard assessment for protected species in a fire-prone landscape

  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/forest-ecology-...

  Citation × Citation Citation Abstract Copy Title: Comparative hazard assessment for protected species in a fire-prone landscape Author: Mealey, Stephen P., Roloff, Gary J., Bailey, John D. 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/forest-ecology-and-management/. Title: Comparative hazard assessment for protected species in a fire-prone landscape Author: Mealey, Stephen P., Roloff, Gary J., Bailey, John D. 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/forest-ecology-and-management/. Close

• 4. [Article] Factors influencing density, distribution, and mesohabitat selection of juvenile wild salmonids and residual hatchery winter steelhead

  This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors ...

  Citation × Citation Citation Abstract Copy Title: Factors influencing density, distribution, and mesohabitat selection of juvenile wild salmonids and residual hatchery winter steelhead Author: Schreck, Carl B., Olson, Douglas E., Schaller, Howard A., Brignon, William R. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Factors influencing density, distribution, and mesohabitat selection of juvenile wild salmonids and residual hatchery winter steelhead Author: Schreck, Carl B., Olson, Douglas E., Schaller, Howard A., Brignon, William R. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 5. [Article] Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current

  In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the ...

  Citation × Citation Citation Abstract Copy Title: Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current Author: Keister, Julie Eileen In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal taxa and biomass in the California Current System was studied using data collected as part of the U.S. Global Ocean Ecosystems Dynamics (GLOBEC) Northeast Pacific Program. Sea surface height from >13 years of satellite altimeter data was used to characterize the spatial and temporal variability in mesoscale circulation in the northern California Current (35°N-49°N) and explore mechanisms of variability. High spatial and temporal variation in mesoscale energy occurred. Energy was not strongly linked to upwelling winds, but did correspond to climate indices, indicating that basin-scale processes play a role in controlling the circulation. CTD casts, zooplankton net tows, and Acoustic Doppler Current Profiler (ADCP) velocities collected during a research cruise conducted in summer 2000 off Oregon and northern California were used to describe the effects of mesoscale circulation on distributions of zooplankton. During the cruise, a filament of the coastal upwelling jet extended seaward of Cape Blanco (42.8°N) resulting in the displacement of coastal zooplankton to >100 km off the continental shelf. Velocities and standing stocks of zooplankton were used to estimate seaward transport of 0.5 Sv in the upper 100 m of the filament, in which zooplankton biomass averaged ~20 mg carbon/m³. That offshore transport equated to >900 metric tons of carbon each day, and 4-5x10⁴ tons over the 6-8 week lifetime of the circulation feature. Although the flux represented a small portion (<2%) of the shelf zooplankton biomass, the transport resulted in an offshore "hot-spot" in which biomass was 3-4X higher than in the surrounding ocean. Distributions of early life history stages of euphausiids indicated that retention of coastal populations may be strongly affected by the offshore advection. Finally, satellite sea surface temperature (SST) and sampling conducted during five summers were used to explore variability in the relationship between mesoscale circulation features and distributions of zooplankton. Circulation patterns differed among cruises and were reflected in zooplankton distributions. Circulation features resulted in the occurrence of cold surface water and coastal taxa offshore, but species abundances and presence/absence of taxa at specific locations were not predictable from satellite SSTs. These results are relevant to studies of ecosystem dynamics and the global carbon cycle because mesoscale circulation plays an important role in the seaward transport of carbon, retention and loss of taxa from the continental shelf, and creation of offshore structure which may be exploited by upper trophic level organisms. Title: Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current Author: Keister, Julie Eileen In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal taxa and biomass in the California Current System was studied using data collected as part of the U.S. Global Ocean Ecosystems Dynamics (GLOBEC) Northeast Pacific Program. Sea surface height from >13 years of satellite altimeter data was used to characterize the spatial and temporal variability in mesoscale circulation in the northern California Current (35°N-49°N) and explore mechanisms of variability. High spatial and temporal variation in mesoscale energy occurred. Energy was not strongly linked to upwelling winds, but did correspond to climate indices, indicating that basin-scale processes play a role in controlling the circulation. CTD casts, zooplankton net tows, and Acoustic Doppler Current Profiler (ADCP) velocities collected during a research cruise conducted in summer 2000 off Oregon and northern California were used to describe the effects of mesoscale circulation on distributions of zooplankton. During the cruise, a filament of the coastal upwelling jet extended seaward of Cape Blanco (42.8°N) resulting in the displacement of coastal zooplankton to >100 km off the continental shelf. Velocities and standing stocks of zooplankton were used to estimate seaward transport of 0.5 Sv in the upper 100 m of the filament, in which zooplankton biomass averaged ~20 mg carbon/m³. That offshore transport equated to >900 metric tons of carbon each day, and 4-5x10⁴ tons over the 6-8 week lifetime of the circulation feature. Although the flux represented a small portion (<2%) of the shelf zooplankton biomass, the transport resulted in an offshore "hot-spot" in which biomass was 3-4X higher than in the surrounding ocean. Distributions of early life history stages of euphausiids indicated that retention of coastal populations may be strongly affected by the offshore advection. Finally, satellite sea surface temperature (SST) and sampling conducted during five summers were used to explore variability in the relationship between mesoscale circulation features and distributions of zooplankton. Circulation patterns differed among cruises and were reflected in zooplankton distributions. Circulation features resulted in the occurrence of cold surface water and coastal taxa offshore, but species abundances and presence/absence of taxa at specific locations were not predictable from satellite SSTs. These results are relevant to studies of ecosystem dynamics and the global carbon cycle because mesoscale circulation plays an important role in the seaward transport of carbon, retention and loss of taxa from the continental shelf, and creation of offshore structure which may be exploited by upper trophic level organisms. Close

• 6. [Article] Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades

  This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches ...

  Citation × Citation Citation Abstract Copy Title: Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades Author: Ratcliff, Christopher J. This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches of the McKenzie River watershed of the Oregon Cascade Mountains. We tested the use of Δ¹³C values from latewood, corroborated by tree-ring width chronologies as precipitation proxies to develop correlations between moisture stress and climate variables. Tree species at each site included Douglas-fir and mountain hemlock. Interpolated meteorological and snowpack data included snow water equivalent (SWE), precipitation, atmospheric temperature, vapor pressure deficit (VPD), relative humidity (RH), and a metric estimating growing season length. Significant correlations between latewood Δ¹³C and winter SWE at each site indicated the importance of winter snowpack to our selected tree species (r = 0.35, r = 0.43). Late summer precipitation and relative humidity (RH) were also significantly correlated with Δ¹³C (r = 0.49, r = 0.46; r = 0.43, r = 0.44). High correlations at both sites reinforced that late summer VPD was the primary driver of Δ¹³C (r = - 0.67, r = -0.61), which is often associated with moisture stress. This was further supported by correlations between air temperature and Δ¹³C (r = -0.46, r = -0.47), which drives much of the variation in VPD. Growing season length also showed significance in mountain hemlocks at the site with longer average snowpack (r = -0.22, r = -0.44). Moisture supplied by spring snow melt is a seasonably limited resource, nonetheless both sites clearly showed that snowpack acts as a valuable moisture subsidy to coniferous mountain forests in the Oregon Cascades. This study acts as a useful case study for future investigations into the relationship between snowpack and forest health in the Pacific North West. Title: Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades Author: Ratcliff, Christopher J. This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches of the McKenzie River watershed of the Oregon Cascade Mountains. We tested the use of Δ¹³C values from latewood, corroborated by tree-ring width chronologies as precipitation proxies to develop correlations between moisture stress and climate variables. Tree species at each site included Douglas-fir and mountain hemlock. Interpolated meteorological and snowpack data included snow water equivalent (SWE), precipitation, atmospheric temperature, vapor pressure deficit (VPD), relative humidity (RH), and a metric estimating growing season length. Significant correlations between latewood Δ¹³C and winter SWE at each site indicated the importance of winter snowpack to our selected tree species (r = 0.35, r = 0.43). Late summer precipitation and relative humidity (RH) were also significantly correlated with Δ¹³C (r = 0.49, r = 0.46; r = 0.43, r = 0.44). High correlations at both sites reinforced that late summer VPD was the primary driver of Δ¹³C (r = - 0.67, r = -0.61), which is often associated with moisture stress. This was further supported by correlations between air temperature and Δ¹³C (r = -0.46, r = -0.47), which drives much of the variation in VPD. Growing season length also showed significance in mountain hemlocks at the site with longer average snowpack (r = -0.22, r = -0.44). Moisture supplied by spring snow melt is a seasonably limited resource, nonetheless both sites clearly showed that snowpack acts as a valuable moisture subsidy to coniferous mountain forests in the Oregon Cascades. This study acts as a useful case study for future investigations into the relationship between snowpack and forest health in the Pacific North West. Close

• 7. [Article] Utilizing hunter harvest effort to survey for wildlife disease: A case study of West Nile virus in greater sage‐grouse

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Wildlife Society ...

  Citation × Citation Citation Abstract Copy Title: Utilizing hunter harvest effort to survey for wildlife disease: A case study of West Nile virus in greater sage‐grouse Author: Hofmeister, Erik K., Dusek, Robert J., Franson, J. Christian, Hagen, Christian A., Budeau, David A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5463a Title: Utilizing hunter harvest effort to survey for wildlife disease: A case study of West Nile virus in greater sage‐grouse Author: Hofmeister, Erik K., Dusek, Robert J., Franson, J. Christian, Hagen, Christian A., Budeau, David A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5463a Close

• 8. [Article] Are large macroalgal blooms necessarily bad? nutrient impacts on seagrass in upwelling-influenced estuaries

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap

  Citation × Citation Citation Abstract Copy Title: Are large macroalgal blooms necessarily bad? nutrient impacts on seagrass in upwelling-influenced estuaries Author: McConville, Sea-oh, Hacker, Sally D., Hessing-Lewis, Margot L., Henderson, Jeremy, Menge, Bruce A. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap Title: Are large macroalgal blooms necessarily bad? nutrient impacts on seagrass in upwelling-influenced estuaries Author: McConville, Sea-oh, Hacker, Sally D., Hessing-Lewis, Margot L., Henderson, Jeremy, Menge, Bruce A. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap Close

• 9. [Article] A new model to simulate climate-change impacts on forest succession for local land management

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Ecological ...

  Citation × Citation Citation Abstract Copy Title: A new model to simulate climate-change impacts on forest succession for local land management Author: Bolte, John P., Bridgham, Scott D., Neilson, Ronald P., et al., Yospin, Gabriel I. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap. Title: A new model to simulate climate-change impacts on forest succession for local land management Author: Bolte, John P., Bridgham, Scott D., Neilson, Ronald P., et al., Yospin, Gabriel I. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap. Close

• 10. [Article] Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone

  Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have ...

  Citation × Citation Citation Abstract Copy Title: Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone Author: Garcia, Maria Osuna Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture, philosophy, and history all play a role in the questions that may be asked today. Examining the past gives light to the questions that are asked in the present and future. Forest ecosystems of the Pacific Northwest are changing as a result of climate change. Rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. As environmental conditions change, Pinus ponderosa may establish within the historic Pinus contorta range. Successful pine species migration will be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study are to establish an informational foundation of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa are dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa. There was no significant difference between EMF communities of P. ponderosa and P. contorta at the species level. Ordination analysis suggests that pH, Bray-phosphorus, total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH₄) and nitrate (NO₃) are driving EMF community composition in P. ponderosa. We found a significant linear relationship between EMF species richness and mineralizable N. Title: Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone Author: Garcia, Maria Osuna Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture, philosophy, and history all play a role in the questions that may be asked today. Examining the past gives light to the questions that are asked in the present and future. Forest ecosystems of the Pacific Northwest are changing as a result of climate change. Rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. As environmental conditions change, Pinus ponderosa may establish within the historic Pinus contorta range. Successful pine species migration will be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study are to establish an informational foundation of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa are dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa. There was no significant difference between EMF communities of P. ponderosa and P. contorta at the species level. Ordination analysis suggests that pH, Bray-phosphorus, total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH₄) and nitrate (NO₃) are driving EMF community composition in P. ponderosa. We found a significant linear relationship between EMF species richness and mineralizable N. Close