Search

Search Results

• 21. [Article] Predictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation in coastal Oregon, U.S.A.

  Spatially explicit information on the species composition and structure of forest vegetation is needed at broad spatial scales for natural resource policy analysis and ecological research. We present a ...

  Citation × Citation Citation Abstract Copy Title: Predictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation in coastal Oregon, U.S.A. Author: Ohmann, Janet L., Gregory, Matthew Jay Spatially explicit information on the species composition and structure of forest vegetation is needed at broad spatial scales for natural resource policy analysis and ecological research. We present a method for predictive vegetation mapping that applies direct gradient analysis and nearest-neighbor imputation to ascribe detailed ground attributes of vegetation to each pixel in a digital landscape map. The gradient nearest neighbor method integrates vegetation measurements from regional grids of field plots, mapped environmental data, and Landsat Thematic Mapper (TM) imagery. In the Oregon coastal province, species gradients were most strongly associated with regional climate and geographic location, whereas variation in forest structure was best explained by Landsat TM variables. At the regional level, mapped predictions represented the range of variability in the sample data, and predicted area by vegetation type closely matched sample-based estimates. At the site level, mapped predictions maintained the covariance structure among multiple response variables. Prediction accuracy for tree species occurrence and several measures of vegetation structure and composition was good to moderate. Vegetation maps produced with the gradient nearest neighbor method are appropriately used for regional-level planning, policy analysis, and research, not to guide local management decisions. Title: Predictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation in coastal Oregon, U.S.A. Author: Ohmann, Janet L., Gregory, Matthew Jay Spatially explicit information on the species composition and structure of forest vegetation is needed at broad spatial scales for natural resource policy analysis and ecological research. We present a method for predictive vegetation mapping that applies direct gradient analysis and nearest-neighbor imputation to ascribe detailed ground attributes of vegetation to each pixel in a digital landscape map. The gradient nearest neighbor method integrates vegetation measurements from regional grids of field plots, mapped environmental data, and Landsat Thematic Mapper (TM) imagery. In the Oregon coastal province, species gradients were most strongly associated with regional climate and geographic location, whereas variation in forest structure was best explained by Landsat TM variables. At the regional level, mapped predictions represented the range of variability in the sample data, and predicted area by vegetation type closely matched sample-based estimates. At the site level, mapped predictions maintained the covariance structure among multiple response variables. Prediction accuracy for tree species occurrence and several measures of vegetation structure and composition was good to moderate. Vegetation maps produced with the gradient nearest neighbor method are appropriately used for regional-level planning, policy analysis, and research, not to guide local management decisions. Close

• 22. [Article] Interrelationships of spodosols, andepts, and ultisols on coastal terraces in Curry County, Oregon

  Distribution and characteristics of soils were determined across a series of six coastal terraces in Curry Co., Oregon. Classification of soils and interrelationships of properties were determined. Soil-landscape ...

  Citation × Citation Citation Abstract Copy Title: Interrelationships of spodosols, andepts, and ultisols on coastal terraces in Curry County, Oregon Author: Hoppe, Diane A. S. Distribution and characteristics of soils were determined across a series of six coastal terraces in Curry Co., Oregon. Classification of soils and interrelationships of properties were determined. Soil-landscape relationships were examined and soil profile development related to relative ages of terraces. Ten pedons were sampled from five terraces of Pleistocene age. All profiles were analyzed for particle size distribution; bulk density; water retention, -1.5 MPa; aluminum and iron extracted with oxalate, citrate-dithionite and sodium pyrophosphate; pH; phosphate retention; exchangeable aluminum; organic carbon; and cation exchange capacity. Andeptic Humitropepts occur on intermediate terraces, in close proximity to the coast. Andeptic Haplohumults occur on the better drained areas of the intermediate terrace, but further inland. Soils in less well drained areas of the intermediate and higher terraces classify as Spodosols, based on morphological features. Ultisols occur on the highest terraces. Profile morphology, particle size and iron extracts are compared between terraces to derive age relationships. Title: Interrelationships of spodosols, andepts, and ultisols on coastal terraces in Curry County, Oregon Author: Hoppe, Diane A. S. Distribution and characteristics of soils were determined across a series of six coastal terraces in Curry Co., Oregon. Classification of soils and interrelationships of properties were determined. Soil-landscape relationships were examined and soil profile development related to relative ages of terraces. Ten pedons were sampled from five terraces of Pleistocene age. All profiles were analyzed for particle size distribution; bulk density; water retention, -1.5 MPa; aluminum and iron extracted with oxalate, citrate-dithionite and sodium pyrophosphate; pH; phosphate retention; exchangeable aluminum; organic carbon; and cation exchange capacity. Andeptic Humitropepts occur on intermediate terraces, in close proximity to the coast. Andeptic Haplohumults occur on the better drained areas of the intermediate terrace, but further inland. Soils in less well drained areas of the intermediate and higher terraces classify as Spodosols, based on morphological features. Ultisols occur on the highest terraces. Profile morphology, particle size and iron extracts are compared between terraces to derive age relationships. Close

• 23. [Article] Evaluating Coastal Protection Services Associated with Restoration Management of an Endangered Shorebird in Oregon, U.S.A.

  Coastal sand dunes and beaches offer a variety of ecosystem services such as coastal protection, sand stabilization, species conservation, and recreation. However, the management and balance of ecosystem ...

  Citation × Citation Citation Abstract Copy Title: Evaluating Coastal Protection Services Associated with Restoration Management of an Endangered Shorebird in Oregon, U.S.A. Author: Carroll, Lindsay J. Coastal sand dunes and beaches offer a variety of ecosystem services such as coastal protection, sand stabilization, species conservation, and recreation. However, the management and balance of ecosystem services offered by dunes and beaches is challenging when ecosystem services interact across the landscape. Management focusing only on one ecosystem service may result in unintended consequences and trade-offs between other key services. Understanding the magnitude of the trade-offs and linkages between services provides a more holistic approach for reducing unintended consequences and maximizing function. The degradation of habitats and land use changes associated with expanding human populations has resulted in the need for species conservation. However, species conservation techniques can sometimes have unintended consequences for other services. Given the mandate of the Endangered Species Act to restore habitat structure and function essential to endangered or threatened species, it becomes critical to evaluate the implications of species conservation management initiatives to reduce negative implications to other key services. The coastal dune systems of the Pacific Northwest (PNW) are a prime example of how ecosystem services, such as species conservation and coastal protection, can interact with one another. Over the last 125 years in the Pacific Northwest (PNW), the intentional introduction of two non-native congeneric beach grasses (Ammophila arenaria and A. breviligulata) has increased coastal protection through the creation of foredunes, but also dramatically altered the dune ecosystem. Both invasive grasses build taller dunes that range from 3 - 18 m in height compared to the native grass, Elymus mollis. Increased foredune elevations generate greater coastal protection services that are increasingly important given sea level rise and extreme storm events on the PNW coast. However, the beach grasses have dramatically changed the beach/dune community, resulting in the decline of several native dune plants and animals. One species that is negatively affected by the grass invasion is the Western snowy plover (Charadrius nivosus nivosus), an endemic shorebird living on beaches and dunes in the Pacific Northwest. This shorebird was listed threatened under the Endangered Species Act in 1993 and a recovery plan was established that employed multiple recovery techniques. The most important part of the plan involves establishing habitat restoration areas (HRAs) where dunes are bulldozed, reducing dune elevations, burying the grass, and returning the dunes to an open shifting sand environment, historically preferred by the plover. Recent coastal hazards modeling revealed that the changes in beach and dune shape associated with plover restoration increases coastal exposure to flooding and erosion at certain locations along the Oregon coast, particularly under projected climate change scenarios of sea level rise and extreme storms. As part of future plover management, four critical habitat areas were proposed for Tillamook County, Oregon: Nehalem River Spit, Bayocean Spit, Netarts Spit, and Sand Lake South. Given the interest in plover habitat restoration in Tillamook County, this research project addresses the following questions: (1) What is the present day dune geomorphology and exposure to coastal hazards at four proposed critical habitat (PCH) areas in Tillamook County, Oregon; and (2) how do changes in beach geomorphology associated with different restoration scenarios alter coastal exposure today, under projected sea level rise and storm scenarios? To address the coastal geomorphological impacts of HRA installation on the four proposed areas, multiple restoration scenarios that reduce foredune elevation were evaluated under present day sea level and potential future sea level rise and extreme storminess scenarios, using coastal exposure modeling techniques. The model projections provide site-specific information on the exposure of HRAs to overtopping under different restoration conditions. We determined that exposure to flooding was dependent on proposed HRA site and restoration scenario, and was exacerbated by sea level rise and extreme storms. Empirical models projected the greatest flooding exposure would occur at Nehalem River Spit, followed by Netarts Spit, and then Bayocean Spit and Sand Lake South, which did not differ. Exposure to flooding at present day dunes was low across all sites, but with increasing exposure to flooding as foredune elevations were reduced to 6.0 m or below, as could happen with plover habitat restoration. Under present day water levels, restoring foredune elevations to 6.0 m or below would likely result in roughly 5 days of overtopping per year at Nehalem River Spit, Bayocean Spit, and Netarts Spit, and 4 days of overtopping at Sand Lake South. Flooding under various foredune restoration scenarios increased under higher sea level rise scenarios. Flooding exposure for the 6.0 m restoration scenario exceeded 10 days per year at Nehalem River Spit and 5 days per year at Bayocean Spit, Netarts Spit, and Sand Lake South. Overall exposure to flooding under the extreme storm scenarios was dependent on proposed HRA site, restoration scenario, and increased wave conditions, such as wave height, period, and water level. Similar to the empirical model, flooding exposure under extreme storm scenarios increased when foredune elevations were reduced to 6.0 m or below, across all sites. The site with the greatest overall flooding exposure during extreme storms was Bayocean Spit. Flooding distance was dependent on restoration scenario and site while flooding duration was only dependent on restoration scenario. The 5.5 m restoration scenario under higher storm water levels resulted in one hour or more of flooding exposure at least one day per year at Nehalem River Spit, Netarts Spit, and Bayocean Spit. The overall likelihood of overwash extending to 150 m or more into the dune field during extreme storms was at least 5 days when selecting to reduce foredune to restoration elevations of 7.0 m or below across all sites. The effect of higher wave heights and greater wave periods was more important to overtopping distance than restoration scenario. Learning from current plover management, combined with the coastal exposure analysis we conducted here, could enable managers to develop site-specific restoration plans that maximize plover recovery while minimizing coastal exposure. This research will give resource managers information on the coastal exposure associated with proposed HRAs and the foredune reduction scenarios they might want to employ at the different sites. It will allow them to identify the best restoration scenarios to maximum habitat restoration without compromising coastal protection, and thus balance some important services of dunes and beaches. Regardless of management objective, identifying the unintended consequences of restoration to key ecosystem services is necessary for the holistic management of our dynamic coasts, especially with projected sea level rise and the uncertainty of frequent and extreme storms. Title: Evaluating Coastal Protection Services Associated with Restoration Management of an Endangered Shorebird in Oregon, U.S.A. Author: Carroll, Lindsay J. Coastal sand dunes and beaches offer a variety of ecosystem services such as coastal protection, sand stabilization, species conservation, and recreation. However, the management and balance of ecosystem services offered by dunes and beaches is challenging when ecosystem services interact across the landscape. Management focusing only on one ecosystem service may result in unintended consequences and trade-offs between other key services. Understanding the magnitude of the trade-offs and linkages between services provides a more holistic approach for reducing unintended consequences and maximizing function. The degradation of habitats and land use changes associated with expanding human populations has resulted in the need for species conservation. However, species conservation techniques can sometimes have unintended consequences for other services. Given the mandate of the Endangered Species Act to restore habitat structure and function essential to endangered or threatened species, it becomes critical to evaluate the implications of species conservation management initiatives to reduce negative implications to other key services. The coastal dune systems of the Pacific Northwest (PNW) are a prime example of how ecosystem services, such as species conservation and coastal protection, can interact with one another. Over the last 125 years in the Pacific Northwest (PNW), the intentional introduction of two non-native congeneric beach grasses (Ammophila arenaria and A. breviligulata) has increased coastal protection through the creation of foredunes, but also dramatically altered the dune ecosystem. Both invasive grasses build taller dunes that range from 3 - 18 m in height compared to the native grass, Elymus mollis. Increased foredune elevations generate greater coastal protection services that are increasingly important given sea level rise and extreme storm events on the PNW coast. However, the beach grasses have dramatically changed the beach/dune community, resulting in the decline of several native dune plants and animals. One species that is negatively affected by the grass invasion is the Western snowy plover (Charadrius nivosus nivosus), an endemic shorebird living on beaches and dunes in the Pacific Northwest. This shorebird was listed threatened under the Endangered Species Act in 1993 and a recovery plan was established that employed multiple recovery techniques. The most important part of the plan involves establishing habitat restoration areas (HRAs) where dunes are bulldozed, reducing dune elevations, burying the grass, and returning the dunes to an open shifting sand environment, historically preferred by the plover. Recent coastal hazards modeling revealed that the changes in beach and dune shape associated with plover restoration increases coastal exposure to flooding and erosion at certain locations along the Oregon coast, particularly under projected climate change scenarios of sea level rise and extreme storms. As part of future plover management, four critical habitat areas were proposed for Tillamook County, Oregon: Nehalem River Spit, Bayocean Spit, Netarts Spit, and Sand Lake South. Given the interest in plover habitat restoration in Tillamook County, this research project addresses the following questions: (1) What is the present day dune geomorphology and exposure to coastal hazards at four proposed critical habitat (PCH) areas in Tillamook County, Oregon; and (2) how do changes in beach geomorphology associated with different restoration scenarios alter coastal exposure today, under projected sea level rise and storm scenarios? To address the coastal geomorphological impacts of HRA installation on the four proposed areas, multiple restoration scenarios that reduce foredune elevation were evaluated under present day sea level and potential future sea level rise and extreme storminess scenarios, using coastal exposure modeling techniques. The model projections provide site-specific information on the exposure of HRAs to overtopping under different restoration conditions. We determined that exposure to flooding was dependent on proposed HRA site and restoration scenario, and was exacerbated by sea level rise and extreme storms. Empirical models projected the greatest flooding exposure would occur at Nehalem River Spit, followed by Netarts Spit, and then Bayocean Spit and Sand Lake South, which did not differ. Exposure to flooding at present day dunes was low across all sites, but with increasing exposure to flooding as foredune elevations were reduced to 6.0 m or below, as could happen with plover habitat restoration. Under present day water levels, restoring foredune elevations to 6.0 m or below would likely result in roughly 5 days of overtopping per year at Nehalem River Spit, Bayocean Spit, and Netarts Spit, and 4 days of overtopping at Sand Lake South. Flooding under various foredune restoration scenarios increased under higher sea level rise scenarios. Flooding exposure for the 6.0 m restoration scenario exceeded 10 days per year at Nehalem River Spit and 5 days per year at Bayocean Spit, Netarts Spit, and Sand Lake South. Overall exposure to flooding under the extreme storm scenarios was dependent on proposed HRA site, restoration scenario, and increased wave conditions, such as wave height, period, and water level. Similar to the empirical model, flooding exposure under extreme storm scenarios increased when foredune elevations were reduced to 6.0 m or below, across all sites. The site with the greatest overall flooding exposure during extreme storms was Bayocean Spit. Flooding distance was dependent on restoration scenario and site while flooding duration was only dependent on restoration scenario. The 5.5 m restoration scenario under higher storm water levels resulted in one hour or more of flooding exposure at least one day per year at Nehalem River Spit, Netarts Spit, and Bayocean Spit. The overall likelihood of overwash extending to 150 m or more into the dune field during extreme storms was at least 5 days when selecting to reduce foredune to restoration elevations of 7.0 m or below across all sites. The effect of higher wave heights and greater wave periods was more important to overtopping distance than restoration scenario. Learning from current plover management, combined with the coastal exposure analysis we conducted here, could enable managers to develop site-specific restoration plans that maximize plover recovery while minimizing coastal exposure. This research will give resource managers information on the coastal exposure associated with proposed HRAs and the foredune reduction scenarios they might want to employ at the different sites. It will allow them to identify the best restoration scenarios to maximum habitat restoration without compromising coastal protection, and thus balance some important services of dunes and beaches. Regardless of management objective, identifying the unintended consequences of restoration to key ecosystem services is necessary for the holistic management of our dynamic coasts, especially with projected sea level rise and the uncertainty of frequent and extreme storms. Close

• 24. [Article] Evaluating spatial patterns of drought-induced tree mortality in a coastal California pine forest

  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/forest-ecology-a...

  Citation × Citation Citation Abstract Copy Title: Evaluating spatial patterns of drought-induced tree mortality in a coastal California pine forest Author: Baguskas, Sara A., Still, Christopher J., Bookhagen, Bodo, Peterson, Seth 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/forest-ecology-and-management/. Title: Evaluating spatial patterns of drought-induced tree mortality in a coastal California pine forest Author: Baguskas, Sara A., Still, Christopher J., Bookhagen, Bodo, Peterson, Seth 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/forest-ecology-and-management/. Close

• 25. [Article] A SNP resource for Douglas-fir: de novo transcriptome assembly and SNP detection and validation

  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 BioMed ...

  Citation × Citation Citation Abstract Copy Title: A SNP resource for Douglas-fir: de novo transcriptome assembly and SNP detection and validation Author: Cronn, Richard, Dean, Jeffrey F. D., Knaus, Brian, Howe, Glenn T., Lorenz, W. Walter, Yu, Jianbin, Kolpak, Scott, Dolan, Peter 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 BioMed Central Ltd. and can be found at: http://www.biomedcentral.com/. Title: A SNP resource for Douglas-fir: de novo transcriptome assembly and SNP detection and validation Author: Cronn, Richard, Dean, Jeffrey F. D., Knaus, Brian, Howe, Glenn T., Lorenz, W. Walter, Yu, Jianbin, Kolpak, Scott, Dolan, Peter 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 BioMed Central Ltd. and can be found at: http://www.biomedcentral.com/. Close

• 26. [Article] Biophysical feedback mediates effects of invasive grasses on coastal dune shape

  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/ecol.

  Citation × Citation Citation Abstract Copy Title: Biophysical feedback mediates effects of invasive grasses on coastal dune shape Author: Zarnetske, Phoebe L., Seabloom, Eric W., Hacker, Sally D., Killian, Jason R., Maddux, Timothy B., Cox, Daniel, Ruggiero, Peter 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/ecol. Title: Biophysical feedback mediates effects of invasive grasses on coastal dune shape Author: Zarnetske, Phoebe L., Seabloom, Eric W., Hacker, Sally D., Killian, Jason R., Maddux, Timothy B., Cox, Daniel, Ruggiero, Peter 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/ecol. Close

• 27. [Article] Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA

  Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future ...

  Citation × Citation Citation Abstract Copy Title: Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA Author: Kennedy, Rebecca S.H. Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future amounts of dead wood in two landscapes and region-wide in the Coastal Province of Oregon. The objectives of the first study were to (1) determine whether two landscapes with different recent disturbance histories differ in the amount and characteristics of dead wood; and (2) explore relationships between patterns of dead wood in each landscape to potentially related factors including topography. The objectives of the second study were to (1) describe current regional amounts of dead wood; (2) compare dead wood amounts across ownerships; (3) determine relationships between current dead wood amounts and ownership, current and past vegetation conditions, climate, topography, and soils; and (4) evaluate whether the factors related to dead wood patterns differed according to the scale of analysis. The objectives of the third study were to (1) characterize the projected future change in dead wood amounts in a multi-ownership Province; (2) determine the longevity of present-day dead wood of different types and sizes in relation to amendments from management and stand development; and (3) evaluate differences in management approaches in transitional dynamics and long-term patterns of dead wood. In the first study, I sampled logs and snags at four topographic positions (streams, lower slopes, middle slopes, upper slopes) in the Tillamook State Forest and the Siuslaw National Forest. These two landscapes experienced catastrophic fire at different points in recent history. I developed statistical models relating various attributes of dead wood abundance to biophysical variables related to climate, topography, historical vegetation, current vegetation, soils, and ecoregion. I found that the type and timing of disturbance was important to dead wood amounts and characteristics, and that potential source and sink areas for dead wood were related to topographic position. In particular, lower slopes had higher amounts of logs, and upper slopes had higher basal areas of potential source wood, in the form of snags and legacy (pre-fire) stumps. Climatic factors were of greater relative importance to overall gradients of dead wood in the landscape in which fire occurred less recently. In the second study, I analyzed dead wood data from a region-wide systematic grid of field plots according to ownership and biophysical variables at multiple scales of resolution including plots, subwatersheds. Dead wood abundance and types varied greatly among ownerships, with public lands (Forest Service, Bureau of Land Management, State of Oregon) typically having higher amounts of dead wood and more dead wood in the larger size classes than the private lands (forest industry, non-industrial private). I found that the relative influence of ownership, topography, current and historical vegetation, and climate varied with scale of resolution. Current vegetation was of greater relative importance at finer scales of plots and subwatersheds, whereas climate, topography, and historical vegetation were of greater relative importance at coarser scales of watersheds and subbasins. Ownership was important to overall dead wood gradients at all scales considered. In the third study, by simulating stand development and dead wood dynamics under various forest management scenarios over a 300-year period, I was able to examine the long-term effects of management on dead wood abundance in the Coastal Province. I estimated potential upper bounds for future dead wood amounts. Dead wood amounts increased over time on average across the Province, mainly because of policies on public lands, especially the federal lands under the Northwest Forest Plan. Forest industry, under the Oregon Forest Practices Act and assuming retention of all snags at harvest and thinning, maintained amounts of dead wood that were similar to present-day levels, but size classes shifted toward the smaller sizes as existing large legacy dead wood decomposed. Non-industrial private lands showed increases from very low present-day amounts of dead wood. Across the Province, legacy logs and snags remained present for over a century of the simulation period, and buffered effects of intensive management to dead wood amounts. Variation across landscapes in starting conditions meant that contrasting management approaches had differential effects on long-term dead wood dynamics depending on where they were applied. Current amounts of dead wood and live vegetation patterns in the Province resulted from historical fire and logging. Results of this simulation study indicate that recently established policies oriented toward dead wood production and retention, in the absence of fire or other large- or mid-scale disturbances, are likely to result in increases in dead wood amounts that greatly exceed present-day levels. My results suggest that dead wood patterns of abundance will continue to diverge according to land ownership and that management practices that foster dead wood creation are of increasing importance to the long-term abundance of large dead wood as legacy dead wood is lost through decomposition. Title: Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA Author: Kennedy, Rebecca S.H. Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future amounts of dead wood in two landscapes and region-wide in the Coastal Province of Oregon. The objectives of the first study were to (1) determine whether two landscapes with different recent disturbance histories differ in the amount and characteristics of dead wood; and (2) explore relationships between patterns of dead wood in each landscape to potentially related factors including topography. The objectives of the second study were to (1) describe current regional amounts of dead wood; (2) compare dead wood amounts across ownerships; (3) determine relationships between current dead wood amounts and ownership, current and past vegetation conditions, climate, topography, and soils; and (4) evaluate whether the factors related to dead wood patterns differed according to the scale of analysis. The objectives of the third study were to (1) characterize the projected future change in dead wood amounts in a multi-ownership Province; (2) determine the longevity of present-day dead wood of different types and sizes in relation to amendments from management and stand development; and (3) evaluate differences in management approaches in transitional dynamics and long-term patterns of dead wood. In the first study, I sampled logs and snags at four topographic positions (streams, lower slopes, middle slopes, upper slopes) in the Tillamook State Forest and the Siuslaw National Forest. These two landscapes experienced catastrophic fire at different points in recent history. I developed statistical models relating various attributes of dead wood abundance to biophysical variables related to climate, topography, historical vegetation, current vegetation, soils, and ecoregion. I found that the type and timing of disturbance was important to dead wood amounts and characteristics, and that potential source and sink areas for dead wood were related to topographic position. In particular, lower slopes had higher amounts of logs, and upper slopes had higher basal areas of potential source wood, in the form of snags and legacy (pre-fire) stumps. Climatic factors were of greater relative importance to overall gradients of dead wood in the landscape in which fire occurred less recently. In the second study, I analyzed dead wood data from a region-wide systematic grid of field plots according to ownership and biophysical variables at multiple scales of resolution including plots, subwatersheds. Dead wood abundance and types varied greatly among ownerships, with public lands (Forest Service, Bureau of Land Management, State of Oregon) typically having higher amounts of dead wood and more dead wood in the larger size classes than the private lands (forest industry, non-industrial private). I found that the relative influence of ownership, topography, current and historical vegetation, and climate varied with scale of resolution. Current vegetation was of greater relative importance at finer scales of plots and subwatersheds, whereas climate, topography, and historical vegetation were of greater relative importance at coarser scales of watersheds and subbasins. Ownership was important to overall dead wood gradients at all scales considered. In the third study, by simulating stand development and dead wood dynamics under various forest management scenarios over a 300-year period, I was able to examine the long-term effects of management on dead wood abundance in the Coastal Province. I estimated potential upper bounds for future dead wood amounts. Dead wood amounts increased over time on average across the Province, mainly because of policies on public lands, especially the federal lands under the Northwest Forest Plan. Forest industry, under the Oregon Forest Practices Act and assuming retention of all snags at harvest and thinning, maintained amounts of dead wood that were similar to present-day levels, but size classes shifted toward the smaller sizes as existing large legacy dead wood decomposed. Non-industrial private lands showed increases from very low present-day amounts of dead wood. Across the Province, legacy logs and snags remained present for over a century of the simulation period, and buffered effects of intensive management to dead wood amounts. Variation across landscapes in starting conditions meant that contrasting management approaches had differential effects on long-term dead wood dynamics depending on where they were applied. Current amounts of dead wood and live vegetation patterns in the Province resulted from historical fire and logging. Results of this simulation study indicate that recently established policies oriented toward dead wood production and retention, in the absence of fire or other large- or mid-scale disturbances, are likely to result in increases in dead wood amounts that greatly exceed present-day levels. My results suggest that dead wood patterns of abundance will continue to diverge according to land ownership and that management practices that foster dead wood creation are of increasing importance to the long-term abundance of large dead wood as legacy dead wood is lost through decomposition. Close

• 28. [Article] Ecological thresholds, climate extremes, and tree species' distributions across the Pacific coastal United States

  Species' distributions across the landscape are perhaps the least understood yet most conspicuous features of life on earth. Ecologists have long studied species' distributions; yet, many questions remain ...

  Citation × Citation Citation Abstract Copy Title: Ecological thresholds, climate extremes, and tree species' distributions across the Pacific coastal United States Author: Lintz, Heather E. Species' distributions across the landscape are perhaps the least understood yet most conspicuous features of life on earth. Ecologists have long studied species' distributions; yet, many questions remain about why species occur where they do. Such questions persist largely because species' distributions are complex systems with challenging properties like non-linearity, high dimensionality, and strong interactions. One impediment to our understanding of species' distributions is the use of standard quantitative approaches, which have limitations when applied to data from complex systems. The objective of this work is to develop tools that can be used to improve our understanding of natural complexity, in particular, factors relating to species’ distributions at large scales. Our study systems are tree species’ distributions from Forest Inventory Analysis (FIA) sites across the Pacific coastal USA. This work advances the detection and measurement of thresholds in response surfaces (e.g. representing tree species’ niches), the evaluation of the consequences of a major change in sampling and measurement methodology associated with the FIA program, and the relationship of climatic extremes and means to tree species’ distributions. For more detailed abstract information, please see the pdf. Title: Ecological thresholds, climate extremes, and tree species' distributions across the Pacific coastal United States Author: Lintz, Heather E. Species' distributions across the landscape are perhaps the least understood yet most conspicuous features of life on earth. Ecologists have long studied species' distributions; yet, many questions remain about why species occur where they do. Such questions persist largely because species' distributions are complex systems with challenging properties like non-linearity, high dimensionality, and strong interactions. One impediment to our understanding of species' distributions is the use of standard quantitative approaches, which have limitations when applied to data from complex systems. The objective of this work is to develop tools that can be used to improve our understanding of natural complexity, in particular, factors relating to species’ distributions at large scales. Our study systems are tree species’ distributions from Forest Inventory Analysis (FIA) sites across the Pacific coastal USA. This work advances the detection and measurement of thresholds in response surfaces (e.g. representing tree species’ niches), the evaluation of the consequences of a major change in sampling and measurement methodology associated with the FIA program, and the relationship of climatic extremes and means to tree species’ distributions. For more detailed abstract information, please see the pdf. Close

• 29. [Article] Geoarchaeological Investigations at the Devils Kitchen Site (35CS9), Southern Oregon Coast

  A geoarchaeological investigation was conducted at the Devils Kitchen archaeological site, located in the Devils Kitchen State Park along the southern Oregon coast. In this thesis research, the author ...

  Citation × Citation Citation Abstract Copy Title: Geoarchaeological Investigations at the Devils Kitchen Site (35CS9), Southern Oregon Coast Author: Curteman, Jessica Ann A geoarchaeological investigation was conducted at the Devils Kitchen archaeological site, located in the Devils Kitchen State Park along the southern Oregon coast. In this thesis research, the author paired previous and recent excavated stratigraphy profiles to define culturally significant deposits. These stratigraphic units were defined further geochemically using a multivariate statistical analysis from data gathered by a portable x-ray fluorescence. Radiocarbon dates from excavated charcoal samples associated with cultural artifacts show an intact deposit dating from 10,638±35 to 11,596±37 RCYBP. The author used textural analysis from Ro-Tap sieve shaker data and Munsell color identification extracted from 33 bucket auger units to subsurface test the Devils Kitchen State Park area. The auger samples portray an uplifted aeolian landscape once influenced by alluvial deposition, commonly observed along coastal environments altered by rising sea levels. This research applied a geoarchaeological method to identify deposits of the right age (DORA) that have the potential to contain intact, early evidence of prehistoric people. The identification of DORA can serve as a marker for future coastal research searching for rare, intact paleolandscapes and archaeological deposits dating to the late Pleistocene to mid Holocene. Title: Geoarchaeological Investigations at the Devils Kitchen Site (35CS9), Southern Oregon Coast Author: Curteman, Jessica Ann A geoarchaeological investigation was conducted at the Devils Kitchen archaeological site, located in the Devils Kitchen State Park along the southern Oregon coast. In this thesis research, the author paired previous and recent excavated stratigraphy profiles to define culturally significant deposits. These stratigraphic units were defined further geochemically using a multivariate statistical analysis from data gathered by a portable x-ray fluorescence. Radiocarbon dates from excavated charcoal samples associated with cultural artifacts show an intact deposit dating from 10,638±35 to 11,596±37 RCYBP. The author used textural analysis from Ro-Tap sieve shaker data and Munsell color identification extracted from 33 bucket auger units to subsurface test the Devils Kitchen State Park area. The auger samples portray an uplifted aeolian landscape once influenced by alluvial deposition, commonly observed along coastal environments altered by rising sea levels. This research applied a geoarchaeological method to identify deposits of the right age (DORA) that have the potential to contain intact, early evidence of prehistoric people. The identification of DORA can serve as a marker for future coastal research searching for rare, intact paleolandscapes and archaeological deposits dating to the late Pleistocene to mid Holocene. Close

• 30. [Article] Monitoring design for riparian forests in the Pacific Northwest : research plan

  The goal of this project is to recommend a broadly-acceptale efficient and effective methodology for characterizing streamside riparian attributes in forested settings at the site grain for regional monitoring. ...

  Citation × Citation Citation Abstract Copy Title: Monitoring design for riparian forests in the Pacific Northwest : research plan Author: Bollman, Mike, National Health and Environmental Effects Laboratory., Oregon State University, Stepp, Jennifer, United States. Environmental Protection Agency. ǂb Office of Research and Development, United States. Forest Service, Barker, Jerry R., Bradshaw, Gay, Ringold, Paul L., Cline, Steven Paul, Carson, Ward, Dynamac Corporation, Fiorella, Maria R. The goal of this project is to recommend a broadly-acceptale efficient and effective methodology for characterizing streamside riparian attributes in forested settings at the site grain for regional monitoring. The authors consider monitoring design in the context of three interacting constraints: ecological functions, capabilities of technologies, and user needs. The focus is on fine grained remote methods. Comparison between candidate selected monitoring systems provides for an initial formulation of a monitoring design. A series of evaluations of these initial formulations provides for an initial recommendation. With the state's interest in the status of coastal fishes, and the programmatic interest of EPA's Western Ecology Division, the areas selected for study are in the Oregon coastal province and the Willamette basin. Title: Monitoring design for riparian forests in the Pacific Northwest : research plan Author: Bollman, Mike, National Health and Environmental Effects Laboratory., Oregon State University, Stepp, Jennifer, United States. Environmental Protection Agency. ǂb Office of Research and Development, United States. Forest Service, Barker, Jerry R., Bradshaw, Gay, Ringold, Paul L., Cline, Steven Paul, Carson, Ward, Dynamac Corporation, Fiorella, Maria R. The goal of this project is to recommend a broadly-acceptale efficient and effective methodology for characterizing streamside riparian attributes in forested settings at the site grain for regional monitoring. The authors consider monitoring design in the context of three interacting constraints: ecological functions, capabilities of technologies, and user needs. The focus is on fine grained remote methods. Comparison between candidate selected monitoring systems provides for an initial formulation of a monitoring design. A series of evaluations of these initial formulations provides for an initial recommendation. With the state's interest in the status of coastal fishes, and the programmatic interest of EPA's Western Ecology Division, the areas selected for study are in the Oregon coastal province and the Willamette basin. Close