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• 1. [Article] A historical reconstruction and land use history of six tidal wetlands in Oregon

  Citation × Citation Citation Abstract Copy Title: A historical reconstruction and land use history of six tidal wetlands in Oregon Author: Hennessey, Jennifer Taylor Title: A historical reconstruction and land use history of six tidal wetlands in Oregon Author: Hennessey, Jennifer Taylor Close

• 2. [Article] A land use history of Benton County, Oregon

  Citation × Citation Citation Abstract Copy Title: A land use history of Benton County, Oregon Author: Longwood, Franklin Russell Title: A land use history of Benton County, Oregon Author: Longwood, Franklin Russell Close

• 3. [Article] Warming and earlier spring increase western U.S. forest wildfire activity

  Western United States forest wildfire activity is widely thought to have increased in recent decades, yet neither the extent of recent changes nor the degree to which climate may be driving regional changes ...

  Citation × Citation Citation Abstract Copy Title: Warming and earlier spring increase western U.S. forest wildfire activity Author: Swetnam, T.W., Cayan, D.R., Westerling, A.L., Hidalgo, H.G. Western United States forest wildfire activity is widely thought to have increased in recent decades, yet neither the extent of recent changes nor the degree to which climate may be driving regional changes in wildfire has been systematically documented. Much of the public and scientific discussion of changes in western United States wildfire has focused instead on the effects of 19thand 20th-century land-use history. We compiled a comprehensive database of large wildfires in western United States forests since 1970 and compared it with hydroclimatic and land-surface data. Here, we show that large wildfire activity increased suddenly and markedly in the mid-1980s, with higher large-wildfire frequency, longer wildfire durations, and longer wildfire seasons. The greatest increases occurred in mid-elevation, Northern Rockies forests, where land-use histories have relatively little effect on fire risks and are strongly associated with increased spring and summer temperatures and an earlier spring snowmelt. Title: Warming and earlier spring increase western U.S. forest wildfire activity Author: Swetnam, T.W., Cayan, D.R., Westerling, A.L., Hidalgo, H.G. Western United States forest wildfire activity is widely thought to have increased in recent decades, yet neither the extent of recent changes nor the degree to which climate may be driving regional changes in wildfire has been systematically documented. Much of the public and scientific discussion of changes in western United States wildfire has focused instead on the effects of 19thand 20th-century land-use history. We compiled a comprehensive database of large wildfires in western United States forests since 1970 and compared it with hydroclimatic and land-surface data. Here, we show that large wildfire activity increased suddenly and markedly in the mid-1980s, with higher large-wildfire frequency, longer wildfire durations, and longer wildfire seasons. The greatest increases occurred in mid-elevation, Northern Rockies forests, where land-use histories have relatively little effect on fire risks and are strongly associated with increased spring and summer temperatures and an earlier spring snowmelt. Close

• 4. [Article] Warming and earlier spring increase western U.S. forest wildfire activity

  Western United States forest wildfire activity is widely thought to have increased in recent decades, yet neither the extent of recent changes nor the degree to which climate may be driving regional changes ...

  Citation × Citation Citation Abstract Copy Title: Warming and earlier spring increase western U.S. forest wildfire activity Author: Cayan, D. R., Westerling, A. L., Swetnam, T. W., Hidalgo, H. G. Western United States forest wildfire activity is widely thought to have increased in recent decades, yet neither the extent of recent changes nor the degree to which climate may be driving regional changes in wildfire has been systematically documented. Much of the public and scientific discussion of changes in western United States wildfire has focused instead on the effects of 19th- and 20th-century land-use history. We compiled a comprehensive database of large wildfires in western United States forests since 1970 and compared it with hydroclimatic and land-surface data. Here, we show that large wildfire activity increased suddenly and markedly in the mid-1980s, with higher large-wildfire frequency, longer wildfire durations, and longer wildfire seasons. The greatest increases occurred in mid-elevation, Northern Rockies forests, where land-use histories have relatively little effect on fire risks and are strongly associated with increased spring and summer temperatures and an earlier spring snowmelt. Title: Warming and earlier spring increase western U.S. forest wildfire activity Author: Cayan, D. R., Westerling, A. L., Swetnam, T. W., Hidalgo, H. G. Western United States forest wildfire activity is widely thought to have increased in recent decades, yet neither the extent of recent changes nor the degree to which climate may be driving regional changes in wildfire has been systematically documented. Much of the public and scientific discussion of changes in western United States wildfire has focused instead on the effects of 19th- and 20th-century land-use history. We compiled a comprehensive database of large wildfires in western United States forests since 1970 and compared it with hydroclimatic and land-surface data. Here, we show that large wildfire activity increased suddenly and markedly in the mid-1980s, with higher large-wildfire frequency, longer wildfire durations, and longer wildfire seasons. The greatest increases occurred in mid-elevation, Northern Rockies forests, where land-use histories have relatively little effect on fire risks and are strongly associated with increased spring and summer temperatures and an earlier spring snowmelt. Close

• 5. [Article] Historical changes in stream habitats in the Columbia River basin

  Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current ...

  Citation × Citation Citation Abstract Copy Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Close

• 6. [Article] Mason’s Run brook trout (Salvelinus fontinalis): history, management challenges, and recommendations

  Graduation date: 2016

  Citation × Citation Citation Abstract Copy Title: Mason’s Run brook trout (Salvelinus fontinalis): history, management challenges, and recommendations Author: Russell, Joseph D. III Graduation date: 2016 Title: Mason’s Run brook trout (Salvelinus fontinalis): history, management challenges, and recommendations Author: Russell, Joseph D. III Graduation date: 2016 Close

• 7. [Article] Effects of deforestation and land use on biomass, carbon, and nutrient pools in the Los Tuxtlas Region, Mexico

  Land-use change in forested regions of the tropics is currently one of the largest anthropogenic perturbations on earth; it is a force capable of altering biogeochemical cycles at local, regional, and ...

  Citation × Citation Citation Abstract Copy Title: Effects of deforestation and land use on biomass, carbon, and nutrient pools in the Los Tuxtlas Region, Mexico Author: Hughes, R. Flint Land-use change in forested regions of the tropics is currently one of the largest anthropogenic perturbations on earth; it is a force capable of altering biogeochemical cycles at local, regional, and global scales. However, significant uncertainties exist concerning the impact of land-use change on biomass and elemental pools of tropical forests. To evaluate the response of biomass and elemental pools to deforestation and land-use in the Los Tuxtlas Region, Mexico, total aboveground biomass (TAGB), C, N, S, and P pools were quantified along a land-use gradient that included primary forests, pastures, cornfields, and secondary forests. TAGB of primary forests averaged 403 Mg/ha; pastures and cornfields averaged 24 and 23 Mg/ha, respectively. Conversion of primary forests to pastures or cornfields resulted in declines of 94% of aboveground C pools, 92% of aboveground N, 83% of aboveground P, and between 89% and 95% of aboveground S. Soil pools of C, N, and S did not differ significantly between primary forests, pastures, and cornfields. Soil C to a 1 m depth ranged from 166-210 Mg/ha; N and S ranged from 16,O00-2O,000 kg/ha and 340O-38OO kg/ha, respectively. In secondary forests, TAGB increased with increasing forest age; accumulations ranged from 4.8 Mg/ha in a 6-month- old site to 287 Mg/ha in a 50-year-old site. Results indicate that secondary forests will attain the equivalent of primary forest TAGB in 73 years. However, rates of TAGB accumulation were constrained by land-use history; rates decreased with increasing duration of land use prior to abandonment. Soil pools of secondary forests were not correlated to forest age or prior land-use history and did not differ significantly from soil pools of primary forests, pastures, or cornfields. As a group, soils of primary and old secondary forest sites had significantly larger pools of available N and higher rates of nitrification and N mineralization than the combined group of pastures, cornfields, and recently abandoned sites. Currently, the Los Tuxtias Region functions as a net source of greenhouse gases. Regenerating secondary forests have the capacity to counterbalance emissions resulting from deforestation, but presently constitute only a small percentage of the the regional landscape. Title: Effects of deforestation and land use on biomass, carbon, and nutrient pools in the Los Tuxtlas Region, Mexico Author: Hughes, R. Flint Land-use change in forested regions of the tropics is currently one of the largest anthropogenic perturbations on earth; it is a force capable of altering biogeochemical cycles at local, regional, and global scales. However, significant uncertainties exist concerning the impact of land-use change on biomass and elemental pools of tropical forests. To evaluate the response of biomass and elemental pools to deforestation and land-use in the Los Tuxtlas Region, Mexico, total aboveground biomass (TAGB), C, N, S, and P pools were quantified along a land-use gradient that included primary forests, pastures, cornfields, and secondary forests. TAGB of primary forests averaged 403 Mg/ha; pastures and cornfields averaged 24 and 23 Mg/ha, respectively. Conversion of primary forests to pastures or cornfields resulted in declines of 94% of aboveground C pools, 92% of aboveground N, 83% of aboveground P, and between 89% and 95% of aboveground S. Soil pools of C, N, and S did not differ significantly between primary forests, pastures, and cornfields. Soil C to a 1 m depth ranged from 166-210 Mg/ha; N and S ranged from 16,O00-2O,000 kg/ha and 340O-38OO kg/ha, respectively. In secondary forests, TAGB increased with increasing forest age; accumulations ranged from 4.8 Mg/ha in a 6-month- old site to 287 Mg/ha in a 50-year-old site. Results indicate that secondary forests will attain the equivalent of primary forest TAGB in 73 years. However, rates of TAGB accumulation were constrained by land-use history; rates decreased with increasing duration of land use prior to abandonment. Soil pools of secondary forests were not correlated to forest age or prior land-use history and did not differ significantly from soil pools of primary forests, pastures, or cornfields. As a group, soils of primary and old secondary forest sites had significantly larger pools of available N and higher rates of nitrification and N mineralization than the combined group of pastures, cornfields, and recently abandoned sites. Currently, the Los Tuxtias Region functions as a net source of greenhouse gases. Regenerating secondary forests have the capacity to counterbalance emissions resulting from deforestation, but presently constitute only a small percentage of the the regional landscape. Close

• 8. [Article] Oregon Explorer : Natural resources information for current and future decision-makers

  Oregon Explorer (www.oregonexplorer.info), a natural resources digital library developed by Oregon State University Libraries and the Institute for Natural Resources, was created for Oregon’s natural resource ...

  Citation × Citation Citation Abstract Copy Title: Oregon Explorer : Natural resources information for current and future decision-makers Author: Salwasser, Janine, Wirth, Andrea A. Oregon Explorer (www.oregonexplorer.info), a natural resources digital library developed by Oregon State University Libraries and the Institute for Natural Resources, was created for Oregon’s natural resource decision-makers to promote informed and streamlined public and private decision-making. Examples of projects and successes of the Oregon Explorer include a basin portal for the Umpqua River, developed in conjunction with the Partnership for Umpqua Rivers, as well as topic portals, such as the Land Use Explorer launched in October 2007 to inform Oregonians about land use history and current issues. We have learned that in the natural resources arena, user needs change with different geographies, yet the adaptations made at the local level are useful in expanding the content and services delivered at the statewide level. It is not enough to just provide access to data or documents. Users want access to a wide variety of integrated information resources—digital documents, interactive maps and reports, decision support, high resolution imagery, and access to available expertise. With Oregon Explorer becoming established as a tool for decision-makers and citizens, members of the team are exploring opportunities to use the digital library in classroom settings. Students in Oregon’s K-12 schools and OSU’s undergraduates are groups that we feel could benefit from the natural resources information and tools available. Proposals are being developed to extend Oregon Explorer’s capabilities for use in primary and secondary education. Oregon Explorer is being used in several university classrooms and will become more integrated as the content and tools grow and as strategies for further incorporation are developed. This evolving natural resources digital library will enable current and future decision-makers to learn about Oregon's environment and to actively engage in creating and sharing knowledge before decisions are made. Title: Oregon Explorer : Natural resources information for current and future decision-makers Author: Salwasser, Janine, Wirth, Andrea A. Oregon Explorer (www.oregonexplorer.info), a natural resources digital library developed by Oregon State University Libraries and the Institute for Natural Resources, was created for Oregon’s natural resource decision-makers to promote informed and streamlined public and private decision-making. Examples of projects and successes of the Oregon Explorer include a basin portal for the Umpqua River, developed in conjunction with the Partnership for Umpqua Rivers, as well as topic portals, such as the Land Use Explorer launched in October 2007 to inform Oregonians about land use history and current issues. We have learned that in the natural resources arena, user needs change with different geographies, yet the adaptations made at the local level are useful in expanding the content and services delivered at the statewide level. It is not enough to just provide access to data or documents. Users want access to a wide variety of integrated information resources—digital documents, interactive maps and reports, decision support, high resolution imagery, and access to available expertise. With Oregon Explorer becoming established as a tool for decision-makers and citizens, members of the team are exploring opportunities to use the digital library in classroom settings. Students in Oregon’s K-12 schools and OSU’s undergraduates are groups that we feel could benefit from the natural resources information and tools available. Proposals are being developed to extend Oregon Explorer’s capabilities for use in primary and secondary education. Oregon Explorer is being used in several university classrooms and will become more integrated as the content and tools grow and as strategies for further incorporation are developed. This evolving natural resources digital library will enable current and future decision-makers to learn about Oregon's environment and to actively engage in creating and sharing knowledge before decisions are made. Close

• 9. [Article] Mesoscale Variation in Snag and Hardwood Densities and Sizes in Old-Growth Forests in Western Oregon

  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 Society ...

  Citation × Citation Citation Abstract Copy Title: Mesoscale Variation in Snag and Hardwood Densities and Sizes in Old-Growth Forests in Western Oregon Author: Bright, Cheryl, Puettmann, Klaus, Ares, Adrian 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 Society of American Foresters and can be found at: http://www.safnet.org/. Title: Mesoscale Variation in Snag and Hardwood Densities and Sizes in Old-Growth Forests in Western Oregon Author: Bright, Cheryl, Puettmann, Klaus, Ares, Adrian 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 Society of American Foresters and can be found at: http://www.safnet.org/. Close

• 10. [Article] Hydrologic and Land Cover Effects on Sources and Fate of In-Stream Fluorescent Dissolved Organic Matter

  Dissolved organic matter (DOM) is a critical component of the carbon cycle linking terrestrial and aquatic ecosystems. Although many factors influence DOM fluxes and quality in rivers, controls on DOM ...

  Citation × Citation Citation Abstract Copy Title: Hydrologic and Land Cover Effects on Sources and Fate of In-Stream Fluorescent Dissolved Organic Matter Author: Lee, Baek Soo P. Dissolved organic matter (DOM) is a critical component of the carbon cycle linking terrestrial and aquatic ecosystems. Although many factors influence DOM fluxes and quality in rivers, controls on DOM compositions in catchments of the western U.S. are poorly understood. UV and fluorescent spectroscopy is a simpler, faster, and less expensive DOM fingerprinting technique compared to techniques, such as nuclear magnetic resonance (NMR) spectroscopy or wet chemical fractionation, and could be useful for characterizing complex DOM chemistry. However, only 1 % of DOM is estimated to be fluorescent, and the utility of UV and fluorescent spectroscopy for DOM characterization needs to be further investigated. This dissertation applied UV and fluorescent spectroscopy to examine hydrologic and land cover controls on DOM chemistry in streams of 45 catchments in the forested headwaters and a mixed landscape of the Willamette River Basin, Oregon, based on two years of monitoring. This dissertation contributes three major findings. First, freezing of water alters DOM chemistry by preferentially precipitating aromatic DOM. Second, UV and fluorescent spectroscopy was able to discriminate DOM delivered from highly processed, proteinrich deep subsurface sources during dry seasons especially in forested headwater streams of the H. J. Andrews Experimental Forest (HJA), where nitrogen inputs are very low. In addition, fluorescent DOM chemistry differed among watersheds with varying forest management history. Third, although fluorescent DOM in a headwater forested system differed among land use history, fluorescent DOM composition did not vary among streams draining a well-mixed landscape of urban, pasture/hay, forest, and agricultural land cover types in the central Willamette River Basin, where nitrogen inputs to streams are relatively high. Dissolved organic carbon (DOC) concentration decreased and the fluorescent index indicated an increase in terrestrial sources of DOM from small (1st and 2nd order) to large (4th to 6th order) streams. A protein-like DOM component that was detected in the headwater forested study site (HJA) was not detected in stream samples from the middle basin study site. These findings indicate that in-stream respiration, fueled by nutrient additions from agriculture runoff, consumes bioavailable, labile DOM (proteins) preferentially relative to more recalcitrant, terrestrial sources of DOM along water flow paths from headwater streams to major rivers. This study shows the clear applicability of the fluorescent characterization of DOM in identifying hydrologic and landscape controls as well as varying DOM chemistry and functions throughout watershed ecosystems. Title: Hydrologic and Land Cover Effects on Sources and Fate of In-Stream Fluorescent Dissolved Organic Matter Author: Lee, Baek Soo P. Dissolved organic matter (DOM) is a critical component of the carbon cycle linking terrestrial and aquatic ecosystems. Although many factors influence DOM fluxes and quality in rivers, controls on DOM compositions in catchments of the western U.S. are poorly understood. UV and fluorescent spectroscopy is a simpler, faster, and less expensive DOM fingerprinting technique compared to techniques, such as nuclear magnetic resonance (NMR) spectroscopy or wet chemical fractionation, and could be useful for characterizing complex DOM chemistry. However, only 1 % of DOM is estimated to be fluorescent, and the utility of UV and fluorescent spectroscopy for DOM characterization needs to be further investigated. This dissertation applied UV and fluorescent spectroscopy to examine hydrologic and land cover controls on DOM chemistry in streams of 45 catchments in the forested headwaters and a mixed landscape of the Willamette River Basin, Oregon, based on two years of monitoring. This dissertation contributes three major findings. First, freezing of water alters DOM chemistry by preferentially precipitating aromatic DOM. Second, UV and fluorescent spectroscopy was able to discriminate DOM delivered from highly processed, proteinrich deep subsurface sources during dry seasons especially in forested headwater streams of the H. J. Andrews Experimental Forest (HJA), where nitrogen inputs are very low. In addition, fluorescent DOM chemistry differed among watersheds with varying forest management history. Third, although fluorescent DOM in a headwater forested system differed among land use history, fluorescent DOM composition did not vary among streams draining a well-mixed landscape of urban, pasture/hay, forest, and agricultural land cover types in the central Willamette River Basin, where nitrogen inputs to streams are relatively high. Dissolved organic carbon (DOC) concentration decreased and the fluorescent index indicated an increase in terrestrial sources of DOM from small (1st and 2nd order) to large (4th to 6th order) streams. A protein-like DOM component that was detected in the headwater forested study site (HJA) was not detected in stream samples from the middle basin study site. These findings indicate that in-stream respiration, fueled by nutrient additions from agriculture runoff, consumes bioavailable, labile DOM (proteins) preferentially relative to more recalcitrant, terrestrial sources of DOM along water flow paths from headwater streams to major rivers. This study shows the clear applicability of the fluorescent characterization of DOM in identifying hydrologic and landscape controls as well as varying DOM chemistry and functions throughout watershed ecosystems. Close