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• 1. [Article] Economic and social impacts of restoration : a case study of the Great Basin Region

  The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations ...

  Citation × Citation Citation Abstract Copy Title: Economic and social impacts of restoration : a case study of the Great Basin Region Author: Satyal, Vijayanand H. The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations in favor of non-native species. Invasive species are known to damage not only the surrounding ecosystem but also cause economic and non-economic losses to society. This study focuses on economic and social impacts of controlling cheatgrass (Bromus tectorum L.) on the public rangelands of the Great Basin region. This research seeks to examine the economic and social impacts of adopting different restoration strategies (herbicide use, fire, grazing and re-seeding of native grasses). The economic study seeks to assess the cost-effectiveness of adopting any versus none of the restoration strategies using a linear programming multi-period optimization framework. In order to understand if restoration of cheatgrass is socially acceptable and whether the spatial context influences economic decisions, a parallel social attitudinal study examines the perceptions held by ranchers, interest groups, agency personnel and informed public with regard to restoration, the ongoing collaborative project and expected costs of undertaking restoration. The bio-economic study incorporates ranch production and ecological site specific data into representative optimization models and solves to maximize net ranch income subject to market and resource constraints. The economic study found restoration to impact the ranches financially as the degree of restoration increased. Costs of restoration were lowest under baseline conditions and increased in magnitude with use of grazing, fire, herbicide and the integrated strategy respectively. Attitudinal data indicated that the meaning of restoration and social acceptability towards restoration strategies differed within and across stakeholder groups in the Great Basin states of Oregon, Idaho, Nevada and Utah. Title: Economic and social impacts of restoration : a case study of the Great Basin Region Author: Satyal, Vijayanand H. The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations in favor of non-native species. Invasive species are known to damage not only the surrounding ecosystem but also cause economic and non-economic losses to society. This study focuses on economic and social impacts of controlling cheatgrass (Bromus tectorum L.) on the public rangelands of the Great Basin region. This research seeks to examine the economic and social impacts of adopting different restoration strategies (herbicide use, fire, grazing and re-seeding of native grasses). The economic study seeks to assess the cost-effectiveness of adopting any versus none of the restoration strategies using a linear programming multi-period optimization framework. In order to understand if restoration of cheatgrass is socially acceptable and whether the spatial context influences economic decisions, a parallel social attitudinal study examines the perceptions held by ranchers, interest groups, agency personnel and informed public with regard to restoration, the ongoing collaborative project and expected costs of undertaking restoration. The bio-economic study incorporates ranch production and ecological site specific data into representative optimization models and solves to maximize net ranch income subject to market and resource constraints. The economic study found restoration to impact the ranches financially as the degree of restoration increased. Costs of restoration were lowest under baseline conditions and increased in magnitude with use of grazing, fire, herbicide and the integrated strategy respectively. Attitudinal data indicated that the meaning of restoration and social acceptability towards restoration strategies differed within and across stakeholder groups in the Great Basin states of Oregon, Idaho, Nevada and Utah. Close

• 2. [Article] The effects of site preparation on native forb establishment in a wet prairie, Willamette Valley, Oregon

  Wetlands and wet prairies are economically and environmentally valuable ecosystems, but many have been degraded or converted to other uses. As human understanding of wetlands' value has increased, restoration ...

  Citation × Citation Citation Abstract Copy Title: The effects of site preparation on native forb establishment in a wet prairie, Willamette Valley, Oregon Author: Norman, Katherine N. Wetlands and wet prairies are economically and environmentally valuable ecosystems, but many have been degraded or converted to other uses. As human understanding of wetlands' value has increased, restoration efforts have grown correspondingly. Restoration attempts use a diversity of methods, which often include seeding with native plant species. This thesis reports on early results from a restoration project that was conducted in the Willamette Valley of western Oregon on a study site that historically supported wet prairie but had been converted to agricultural use. The site was withdrawn from agricultural use 11 – 12 years prior to the work reported here, contoured to reestablish wetland hydrological conditions, and planted with the native perennial, tufted hairgrass (Deschampsia cespitosa), in a preliminary attempt to recreate wet prairie conditions. The subsequent management goal, addressed in the work reported here, was to increase native species richness without increasing exotic plant cover by seeding the site with a mixture of 27 common wetland natives. In each of three blocks at the site, four units were treated either by burning (N = 2 per block) or mowing (N = 2 per block), then seeded with a mixture of 27 common native wetland species. One each of the burned and mowed units from each block was treated with glyphosate herbicide. Thus burning, burning + herbicide, mowing, mowing + herbicide, all with seeding of native species, and an unseeded control each occurred in one unit in each of three blocks at the site. The specific objectives of this study were to determine: 1. If treatments varied in their effects on plant communities, 2. Whether treatments differed in the degree to which they enhanced establishment of seeded species or other native species, 3. If so, which treatment was most effective at increasing cover or richness of native or seeded species, and 4. Consequences of treatments in terms of exotic species cover or richness. Although the low number of replications (N = 3) limited statistical inference, it appeared post-treatment plant communities differed among treatment groups (including controls) (Blocked Multi-Response Permutation Procedure; A-value 0.249 to 0.312; p-value < 0.005). While all four seeding treatments enhanced cover by native species compared to that in controls, burning without herbicide appeared to be particularly effective. Burning and burning + herbicide enhanced cover of seeded species more than did mowing treatments; while all four seeding treatments appeared to increase richness of native species overall, relative to that in unseeded controls, differences were not statistically significant. However, treatments also tended to increase cover and richness of exotic species relative to those in controls. While the increases in exotic species richness post-treatment were generally smaller than the increases in native species richness, changes in cover tended to be similar between the two species groups. Further monitoring of this site will be necessary to determine longer term consequences of these treatments for the plant communities. Title: The effects of site preparation on native forb establishment in a wet prairie, Willamette Valley, Oregon Author: Norman, Katherine N. Wetlands and wet prairies are economically and environmentally valuable ecosystems, but many have been degraded or converted to other uses. As human understanding of wetlands' value has increased, restoration efforts have grown correspondingly. Restoration attempts use a diversity of methods, which often include seeding with native plant species. This thesis reports on early results from a restoration project that was conducted in the Willamette Valley of western Oregon on a study site that historically supported wet prairie but had been converted to agricultural use. The site was withdrawn from agricultural use 11 – 12 years prior to the work reported here, contoured to reestablish wetland hydrological conditions, and planted with the native perennial, tufted hairgrass (Deschampsia cespitosa), in a preliminary attempt to recreate wet prairie conditions. The subsequent management goal, addressed in the work reported here, was to increase native species richness without increasing exotic plant cover by seeding the site with a mixture of 27 common wetland natives. In each of three blocks at the site, four units were treated either by burning (N = 2 per block) or mowing (N = 2 per block), then seeded with a mixture of 27 common native wetland species. One each of the burned and mowed units from each block was treated with glyphosate herbicide. Thus burning, burning + herbicide, mowing, mowing + herbicide, all with seeding of native species, and an unseeded control each occurred in one unit in each of three blocks at the site. The specific objectives of this study were to determine: 1. If treatments varied in their effects on plant communities, 2. Whether treatments differed in the degree to which they enhanced establishment of seeded species or other native species, 3. If so, which treatment was most effective at increasing cover or richness of native or seeded species, and 4. Consequences of treatments in terms of exotic species cover or richness. Although the low number of replications (N = 3) limited statistical inference, it appeared post-treatment plant communities differed among treatment groups (including controls) (Blocked Multi-Response Permutation Procedure; A-value 0.249 to 0.312; p-value < 0.005). While all four seeding treatments enhanced cover by native species compared to that in controls, burning without herbicide appeared to be particularly effective. Burning and burning + herbicide enhanced cover of seeded species more than did mowing treatments; while all four seeding treatments appeared to increase richness of native species overall, relative to that in unseeded controls, differences were not statistically significant. However, treatments also tended to increase cover and richness of exotic species relative to those in controls. While the increases in exotic species richness post-treatment were generally smaller than the increases in native species richness, changes in cover tended to be similar between the two species groups. Further monitoring of this site will be necessary to determine longer term consequences of these treatments for the plant communities. Close

• 3. [Article] Fire effects on wetland prairie species: final report

  Project No. 14-48-0001-96749

  Citation × Citation Citation Abstract Copy Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Close

• 4. [Article] Ecological Change on California’s Channel Islands from the Pleistocene to the Anthropocene

  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 was published by Oxford University ...

  Citation × Citation Citation Abstract Copy Title: Ecological Change on California’s Channel Islands from the Pleistocene to the Anthropocene Author: Ghalambor, Cameron K., Still, Christopher, Rick, Torben C., et al., Sillett, T. Scott 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 was published by Oxford University Press on behalf of the American Institute of Biological Sciences and is in the public domain. The published article can be found at: http://bioscience.oxfordjournals.org/. Title: Ecological Change on California’s Channel Islands from the Pleistocene to the Anthropocene Author: Ghalambor, Cameron K., Still, Christopher, Rick, Torben C., et al., Sillett, T. Scott 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 was published by Oxford University Press on behalf of the American Institute of Biological Sciences and is in the public domain. The published article can be found at: http://bioscience.oxfordjournals.org/. Close

• 5. [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

• 6. [Article] Plant community dynamics in remnant and restored Willamette Valley wetland prairies

  Invasion by exotic species can pose a major challenge for developing native plant communities in wetland restoration projects. Often native plant communities do not develop as anticipated in restored wetlands ...

  Citation × Citation Citation Abstract Copy Title: Plant community dynamics in remnant and restored Willamette Valley wetland prairies Author: Schwindt, Rachel A. Invasion by exotic species can pose a major challenge for developing native plant communities in wetland restoration projects. Often native plant communities do not develop as anticipated in restored wetlands due to colonization by exotic species that dominate the native plant community. Despite the time and expense to restore wetlands, there has been little long term research to compare plant communities in restored and natural wetland sites. Research into plant community diversity across several wetland sites over several years can provide a broader perspective into how these ecosystems recover from long-term disturbance. The objective of this study was to compare plant community change from 2000 to 2005 between restored and remnant wetland prairie sites in the southern Willamette Valley in Oregon to determine if exotic species abundance was consistent between these groups. Specific objectives included 1) comparing the diversity and abundance of all species in remnant and restored wetland prairie sites, 2) evaluate the trajectory of community change between remnant and restored wetland prairie sites to determine if there was rapid change in restored sites, and 3) describe the plot level heterogeneity of the plant community in all sites to determine how microsites influence diversity. In 2005, species abundance was re-measured in four remnant wetland prairies and four restored wetland prairies that had been selected for an unrelated vegetation survey in 2000. Species were characterized by life form, origin, and wetland indicator status. Species abundance between groups of remnant and restored sites were compared using a multi-response permutation procedure (MRPP). The plant community trajectory was evaluated with nonmetric multidimensional scaling (NMS) and tested for significance with multivariate analysis of variance (MANOVA). Species area curves were compared between sites and within remnant and restored groups of plots. Within-year and between-year significance tests indicated that remnant and restored sites were similar in exotic species abundance, graminoid abundance, and wetland species abundance with no significant difference between these remnant and restored wetland prairie sites. Individual sites in both groups experienced changes in exotic species abundance which confounded the statistical results. Species heterogeneity was no more spatially diverse across the remnant site plots than restored site plots. Species area curves did not show significant differences between remnant and restored plots but individual plots did show homogeneous community characteristics at smaller spatial scales. Restoration sites had developed high graminoid cover by the 2000 survey which was conducted two to three years after restoration was initiated. All sites were equally likely to contain exotic species. Exotic species common across all sites included Centaurium umbellatum, Holcus lanatus, and Hypericum perforatum. Native species common across sites included Deschampsia cespitosa, Danthonia californica and Juncus tenuis. These results suggested that differences between remnant and restored Willamette Valley wetland prairie sites were not generalizable at the landscape scale and were more dependent on site specific management activities and local barriers to colonization. Five years may not be enough time to see evidence that suggests if restored plant communities will develop spatial characteristics of the remnant sites. This research does suggest that multi-site comparisons help distinguish individual sites that are not developing characteristics of remnant wetland plant communities. Title: Plant community dynamics in remnant and restored Willamette Valley wetland prairies Author: Schwindt, Rachel A. Invasion by exotic species can pose a major challenge for developing native plant communities in wetland restoration projects. Often native plant communities do not develop as anticipated in restored wetlands due to colonization by exotic species that dominate the native plant community. Despite the time and expense to restore wetlands, there has been little long term research to compare plant communities in restored and natural wetland sites. Research into plant community diversity across several wetland sites over several years can provide a broader perspective into how these ecosystems recover from long-term disturbance. The objective of this study was to compare plant community change from 2000 to 2005 between restored and remnant wetland prairie sites in the southern Willamette Valley in Oregon to determine if exotic species abundance was consistent between these groups. Specific objectives included 1) comparing the diversity and abundance of all species in remnant and restored wetland prairie sites, 2) evaluate the trajectory of community change between remnant and restored wetland prairie sites to determine if there was rapid change in restored sites, and 3) describe the plot level heterogeneity of the plant community in all sites to determine how microsites influence diversity. In 2005, species abundance was re-measured in four remnant wetland prairies and four restored wetland prairies that had been selected for an unrelated vegetation survey in 2000. Species were characterized by life form, origin, and wetland indicator status. Species abundance between groups of remnant and restored sites were compared using a multi-response permutation procedure (MRPP). The plant community trajectory was evaluated with nonmetric multidimensional scaling (NMS) and tested for significance with multivariate analysis of variance (MANOVA). Species area curves were compared between sites and within remnant and restored groups of plots. Within-year and between-year significance tests indicated that remnant and restored sites were similar in exotic species abundance, graminoid abundance, and wetland species abundance with no significant difference between these remnant and restored wetland prairie sites. Individual sites in both groups experienced changes in exotic species abundance which confounded the statistical results. Species heterogeneity was no more spatially diverse across the remnant site plots than restored site plots. Species area curves did not show significant differences between remnant and restored plots but individual plots did show homogeneous community characteristics at smaller spatial scales. Restoration sites had developed high graminoid cover by the 2000 survey which was conducted two to three years after restoration was initiated. All sites were equally likely to contain exotic species. Exotic species common across all sites included Centaurium umbellatum, Holcus lanatus, and Hypericum perforatum. Native species common across sites included Deschampsia cespitosa, Danthonia californica and Juncus tenuis. These results suggested that differences between remnant and restored Willamette Valley wetland prairie sites were not generalizable at the landscape scale and were more dependent on site specific management activities and local barriers to colonization. Five years may not be enough time to see evidence that suggests if restored plant communities will develop spatial characteristics of the remnant sites. This research does suggest that multi-site comparisons help distinguish individual sites that are not developing characteristics of remnant wetland plant communities. Close

• 7. [Article] A Spatial Assessment of Conservation Opportunities in the Willamette River Floodplain between Corvallis and Albany, Oregon

  The Willamette River floodplain has been highly modified by urbanization, conversion of land to agriculture, construction of dams and revetments, and regulation of flow, all of which have reduced floodplain ...

  Citation × Citation Citation Abstract Copy Title: A Spatial Assessment of Conservation Opportunities in the Willamette River Floodplain between Corvallis and Albany, Oregon Author: Baker, Jeffrey M. The Willamette River floodplain has been highly modified by urbanization, conversion of land to agriculture, construction of dams and revetments, and regulation of flow, all of which have reduced floodplain processes that provide valuable ecosystem services such as fish and wildlife habitat and flood storage. Efforts to protect and restore floodplains have increased in recent years as scientists and conservationists have began to recognize the importance of functioning floodplains to help recover native fish populations and mitigate flood effects. Restoration and protection of floodplain processes is linked to both the past land-uses that degraded the ecological systems and the current uses that sustain rural communities and farmers. This project assessed the opportunities to protect and restore floodplain forests and channel complexity in the floodplain of the Willamette River between Corvallis and Albany, Oregon. A geographic information system was used to analyze suitability for conservation in terms of floodplain forest, channel complexity, and human uses on a pixel by pixel basis across the floodplain. Suitability maps show the best locations to protect and restore floodplain processes while minimizing impacts to human uses in the floodplain. Most land highly suitable for conservation purposes is located near the current river channel. Some identified sites can be restored with little or no impact to private lands while others cross multiple ownerships and will be more challenging to restore. The goal of this project is to contribute to conservation planning and actions in the study area. Title: A Spatial Assessment of Conservation Opportunities in the Willamette River Floodplain between Corvallis and Albany, Oregon Author: Baker, Jeffrey M. The Willamette River floodplain has been highly modified by urbanization, conversion of land to agriculture, construction of dams and revetments, and regulation of flow, all of which have reduced floodplain processes that provide valuable ecosystem services such as fish and wildlife habitat and flood storage. Efforts to protect and restore floodplains have increased in recent years as scientists and conservationists have began to recognize the importance of functioning floodplains to help recover native fish populations and mitigate flood effects. Restoration and protection of floodplain processes is linked to both the past land-uses that degraded the ecological systems and the current uses that sustain rural communities and farmers. This project assessed the opportunities to protect and restore floodplain forests and channel complexity in the floodplain of the Willamette River between Corvallis and Albany, Oregon. A geographic information system was used to analyze suitability for conservation in terms of floodplain forest, channel complexity, and human uses on a pixel by pixel basis across the floodplain. Suitability maps show the best locations to protect and restore floodplain processes while minimizing impacts to human uses in the floodplain. Most land highly suitable for conservation purposes is located near the current river channel. Some identified sites can be restored with little or no impact to private lands while others cross multiple ownerships and will be more challenging to restore. The goal of this project is to contribute to conservation planning and actions in the study area. Close

• 8. [Article] Integrating functional trait frameworks into restoration : the role of seed and seedling traits in recruitment success

  Seeding is a vital tool to facilitate recovery of degraded ecosystems, but low seedling recruitment rates limit the utility of this practice in a range of ecosystems across the globe. Plant functional ...

  Citation × Citation Citation Abstract Copy Title: Integrating functional trait frameworks into restoration : the role of seed and seedling traits in recruitment success Author: Larson, Julie E. Seeding is a vital tool to facilitate recovery of degraded ecosystems, but low seedling recruitment rates limit the utility of this practice in a range of ecosystems across the globe. Plant functional traits impact individual fitness through effects on growth, reproduction and survival. Consequently, seed and seedling trait variation among species provide a critical mechanism to understand and explain variation in recruitment probabilities across restoration species. I measured seed traits, seedling traits, and field probabilities of germination, emergence, seedling establishment, and established seedling survival for 47 varieties of native and introduced grasses in U.S. western drylands. Multivariate analyses were used to identify major dimensions of trait variation across early life stages and to assess whether this trait variation was related to cumulative survival probabilities through the first growing season. Ordination and cluster analysis of seed and seedling traits highlighted two central, independent aspects of functional trait variation among grasses describing seedling growth rate and germination rate, but functional trait-based clusters failed to capture variation in recruitment patterns in the field. Path analysis revealed that variation in germination and emergence probabilities explained over 90% of the variation in cumulative survival in the first growing season. However, functional traits including seed mass, hydrothermal time, and coleoptile tissue density, explained just 16% and 18% of the variation in germination and emergence, respectively, under ambient conditions. The majority of functional trait work has centered on linking leaf and root traits to resource acquisition, utilization, and growth. Our study suggests that germination, emergence and functional traits associated with these processes are leading drivers of recruitment variation across species in restoration scenarios. Functional traits reflecting the physiology and morphology of germinated seedlings, such as coleoptile tissue density, may play a major role in differentiating recruitment success following seeding, but remain largely unexplored. Before functional traits can facilitate practical advances in seeding and restoration efforts, we must improve our understanding of the dimensions and consequences of trait variation during germination and emergence. Title: Integrating functional trait frameworks into restoration : the role of seed and seedling traits in recruitment success Author: Larson, Julie E. Seeding is a vital tool to facilitate recovery of degraded ecosystems, but low seedling recruitment rates limit the utility of this practice in a range of ecosystems across the globe. Plant functional traits impact individual fitness through effects on growth, reproduction and survival. Consequently, seed and seedling trait variation among species provide a critical mechanism to understand and explain variation in recruitment probabilities across restoration species. I measured seed traits, seedling traits, and field probabilities of germination, emergence, seedling establishment, and established seedling survival for 47 varieties of native and introduced grasses in U.S. western drylands. Multivariate analyses were used to identify major dimensions of trait variation across early life stages and to assess whether this trait variation was related to cumulative survival probabilities through the first growing season. Ordination and cluster analysis of seed and seedling traits highlighted two central, independent aspects of functional trait variation among grasses describing seedling growth rate and germination rate, but functional trait-based clusters failed to capture variation in recruitment patterns in the field. Path analysis revealed that variation in germination and emergence probabilities explained over 90% of the variation in cumulative survival in the first growing season. However, functional traits including seed mass, hydrothermal time, and coleoptile tissue density, explained just 16% and 18% of the variation in germination and emergence, respectively, under ambient conditions. The majority of functional trait work has centered on linking leaf and root traits to resource acquisition, utilization, and growth. Our study suggests that germination, emergence and functional traits associated with these processes are leading drivers of recruitment variation across species in restoration scenarios. Functional traits reflecting the physiology and morphology of germinated seedlings, such as coleoptile tissue density, may play a major role in differentiating recruitment success following seeding, but remain largely unexplored. Before functional traits can facilitate practical advances in seeding and restoration efforts, we must improve our understanding of the dimensions and consequences of trait variation during germination and emergence. Close

• 9. [Article] Yield responses of invasive grasses to carbon doses

  The sagebrush steppe ecosystem of the northern Great Basin is severely degraded and continues to decline due in large part to the invasive, non-native annual grasses Bromus tectorum L. (cheatgrass) and ...

  Citation × Citation Citation Abstract Copy Title: Yield responses of invasive grasses to carbon doses Author: Brunson, Jessi L. The sagebrush steppe ecosystem of the northern Great Basin is severely degraded and continues to decline due in large part to the invasive, non-native annual grasses Bromus tectorum L. (cheatgrass) and Taeniatherum caput-medusae (L.) Nevski (medusahead). Restoration of invasive-dominated areas is difficult, but can be enhanced by adding a carbon source, which stimulates microbes to immobilize soil inorganic N and reduces yields of fast-growing ruderal plants. How much carbon is needed to induce this effect is uncertain, so our research objectives were to establish a response to increasing carbon doses and calculate the lowest dose where a significant response was observed for 1) biomass, density, and seed production of cheatgrass and medusahead; 2) soil microbial biomass C and N; and 3) inorganic soil N. In November 2005 we applied 12 carbon doses ranging from 0 to 2400 kg C/ha as sucrose to plots planted with cheatgrass and medusahead at two sites in the northern Great Basin. We measured aboveground plant biomass when plants matured in June and July 2006 and microbial biomass in November 2005, March 2006, and July 2006. Inorganic soil N was measured using mixed-bed resin capsules placed in situ for the duration of the study. For an increase in carbon dose of 100 kg C/ha, back-transformed mean medusahead biomass (g/m²) at one site decreased 6.8%. This was the only significant response to carbon doses for both target species across both sites. In addition to cheatgrass and medusahead, other ruderal plants established in our plots, and the biomass of this entire ruderal community decreased approximately 6% for an increase in carbon dose of 100 kg C/ha at both sites. Microbial biomass C increased 2-4 mg/kg for an increase in carbon of 100 kg C/ha at the two earliest sampling dates at both sites, while microbial biomass N increased at only one site at the earliest sampling date, and this increase was 0.3 mg/kg for an increase in carbon of 100 kg C/ha. Soil NO3₃⁻-N decreased at both sites with increasing carbon. For a significant reduction in ruderal biomass, we calculated lowest significant doses of 240-640 kg C/ha, but it remains to be determined if this reduction is sufficient to facilitate establishment of native perennials in northern Great Basin restoration projects. Title: Yield responses of invasive grasses to carbon doses Author: Brunson, Jessi L. The sagebrush steppe ecosystem of the northern Great Basin is severely degraded and continues to decline due in large part to the invasive, non-native annual grasses Bromus tectorum L. (cheatgrass) and Taeniatherum caput-medusae (L.) Nevski (medusahead). Restoration of invasive-dominated areas is difficult, but can be enhanced by adding a carbon source, which stimulates microbes to immobilize soil inorganic N and reduces yields of fast-growing ruderal plants. How much carbon is needed to induce this effect is uncertain, so our research objectives were to establish a response to increasing carbon doses and calculate the lowest dose where a significant response was observed for 1) biomass, density, and seed production of cheatgrass and medusahead; 2) soil microbial biomass C and N; and 3) inorganic soil N. In November 2005 we applied 12 carbon doses ranging from 0 to 2400 kg C/ha as sucrose to plots planted with cheatgrass and medusahead at two sites in the northern Great Basin. We measured aboveground plant biomass when plants matured in June and July 2006 and microbial biomass in November 2005, March 2006, and July 2006. Inorganic soil N was measured using mixed-bed resin capsules placed in situ for the duration of the study. For an increase in carbon dose of 100 kg C/ha, back-transformed mean medusahead biomass (g/m²) at one site decreased 6.8%. This was the only significant response to carbon doses for both target species across both sites. In addition to cheatgrass and medusahead, other ruderal plants established in our plots, and the biomass of this entire ruderal community decreased approximately 6% for an increase in carbon dose of 100 kg C/ha at both sites. Microbial biomass C increased 2-4 mg/kg for an increase in carbon of 100 kg C/ha at the two earliest sampling dates at both sites, while microbial biomass N increased at only one site at the earliest sampling date, and this increase was 0.3 mg/kg for an increase in carbon of 100 kg C/ha. Soil NO3₃⁻-N decreased at both sites with increasing carbon. For a significant reduction in ruderal biomass, we calculated lowest significant doses of 240-640 kg C/ha, but it remains to be determined if this reduction is sufficient to facilitate establishment of native perennials in northern Great Basin restoration projects. Close