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• 1. [Article] Divergent trends in ecosystem services under different climate-management futures in a fire-prone forest landscape

  While ecosystem services and climate change are often examined independently, quantitative assessments integrating these fields are needed to inform future land management decisions. Using climate-informed ...

  Citation × Citation Citation Abstract Copy Title: Divergent trends in ecosystem services under different climate-management futures in a fire-prone forest landscape Author: Halofsky, Joshua S., Halofsky, Jessica E., Hemstrom, Miles A., Morzillo, Anita T., Zhou, Xiaoping, Donato, Daniel C. Year: 2017 While ecosystem services and climate change are often examined independently, quantitative assessments integrating these fields are needed to inform future land management decisions. Using climate-informed state-and-transition simulations, we examined projected trends and trade-offs for a suite of ecosystem services under four climate change scenarios and two management scenarios (active management emphasizing fuel treatments and no management other than fire suppression) in a fire-prone landscape of dry and moist mixed-conifer forests in central Oregon, USA. Focal ecosystem services included fire potential (regulating service), timber volume (provisioning service), and potential wildlife habitat (supporting service). Projections without climate change suggested active management in dry mixed-conifer forests would create more open forest structures, reduce crown fire potential, and maintain timber stocks, while in moist mixed-conifer forests, active management would reduce crown fire potential but at the expense of timber stocks. When climate change was considered, however, trends in most ecosystem services changed substantially, with large increases in wildfire area predominating broad-scale trends in outputs, regardless of management approach (e.g., strong declines in timber stocks and habitat for closed-forest wildlife species). Active management still had an influence under a changing climate, but as a moderator of the strong climate-driven trends rather than being a principal driver of ecosystem service outputs. These results suggest projections of future ecosystem services that do not consider climate change may result in unrealistic expectations of benefits. Title: Divergent trends in ecosystem services under different climate-management futures in a fire-prone forest landscape Author: Halofsky, Joshua S., Halofsky, Jessica E., Hemstrom, Miles A., Morzillo, Anita T., Zhou, Xiaoping, Donato, Daniel C. Year: 2017 While ecosystem services and climate change are often examined independently, quantitative assessments integrating these fields are needed to inform future land management decisions. Using climate-informed state-and-transition simulations, we examined projected trends and trade-offs for a suite of ecosystem services under four climate change scenarios and two management scenarios (active management emphasizing fuel treatments and no management other than fire suppression) in a fire-prone landscape of dry and moist mixed-conifer forests in central Oregon, USA. Focal ecosystem services included fire potential (regulating service), timber volume (provisioning service), and potential wildlife habitat (supporting service). Projections without climate change suggested active management in dry mixed-conifer forests would create more open forest structures, reduce crown fire potential, and maintain timber stocks, while in moist mixed-conifer forests, active management would reduce crown fire potential but at the expense of timber stocks. When climate change was considered, however, trends in most ecosystem services changed substantially, with large increases in wildfire area predominating broad-scale trends in outputs, regardless of management approach (e.g., strong declines in timber stocks and habitat for closed-forest wildlife species). Active management still had an influence under a changing climate, but as a moderator of the strong climate-driven trends rather than being a principal driver of ecosystem service outputs. These results suggest projections of future ecosystem services that do not consider climate change may result in unrealistic expectations of benefits. Close

• 2. [Article] Predicted Effects of Gypsy Moth Defoliation and Climate Change on Forest Carbon Dynamics in the New Jersey Pine Barrens

  Disturbance regimes within temperate forests can significantly impact carbon cycling. Additionally, projected climate change in combination with multiple, interacting disturbance effects may disrupt the ...

  Citation × Citation Citation Abstract Copy Title: Predicted Effects of Gypsy Moth Defoliation and Climate Change on Forest Carbon Dynamics in the New Jersey Pine Barrens Author: Kretchun, Alec M., Scheller, Robert M., Lucash, Melissa S., Clark, Kenneth L., Hom, John, Van Tuyl, Steve Year: 2014 Disturbance regimes within temperate forests can significantly impact carbon cycling. Additionally, projected climate change in combination with multiple, interacting disturbance effects may disrupt the capacity of forests to act as carbon sinks at large spatial and temporal scales. We used a spatially explicit forest succession and disturbance model, LANDIS-II, to model the effects of climate change, gypsy moth (Lymantria dispar L.) defoliation, and wildfire on the C dynamics of the forests of the New Jersey Pine Barrens over the next century. Climate scenarios were simulated using current climate conditions (baseline), as well as a high emissions scenario (HadCM3 A2 emissions scenario). Our results suggest that long-term changes in C cycling will be driven more by climate change than by fire or gypsy moths over the next century. We also found that simulated disturbances will affect species composition more than tree growth or C sequestration rates at the landscape level. Projected changes in tree species biomass indicate a potential increase in oaks with climate change and gypsy moth defoliation over the course of the 100-year simulation, exacerbating current successional trends towards increased oak abundance. Our research suggests that defoliation under climate change may play a critical role in increasing the variability of tree growth rates and in determining landscape species composition over the next 100 years. Title: Predicted Effects of Gypsy Moth Defoliation and Climate Change on Forest Carbon Dynamics in the New Jersey Pine Barrens Author: Kretchun, Alec M., Scheller, Robert M., Lucash, Melissa S., Clark, Kenneth L., Hom, John, Van Tuyl, Steve Year: 2014 Disturbance regimes within temperate forests can significantly impact carbon cycling. Additionally, projected climate change in combination with multiple, interacting disturbance effects may disrupt the capacity of forests to act as carbon sinks at large spatial and temporal scales. We used a spatially explicit forest succession and disturbance model, LANDIS-II, to model the effects of climate change, gypsy moth (Lymantria dispar L.) defoliation, and wildfire on the C dynamics of the forests of the New Jersey Pine Barrens over the next century. Climate scenarios were simulated using current climate conditions (baseline), as well as a high emissions scenario (HadCM3 A2 emissions scenario). Our results suggest that long-term changes in C cycling will be driven more by climate change than by fire or gypsy moths over the next century. We also found that simulated disturbances will affect species composition more than tree growth or C sequestration rates at the landscape level. Projected changes in tree species biomass indicate a potential increase in oaks with climate change and gypsy moth defoliation over the course of the 100-year simulation, exacerbating current successional trends towards increased oak abundance. Our research suggests that defoliation under climate change may play a critical role in increasing the variability of tree growth rates and in determining landscape species composition over the next 100 years. Close

• 3. [Article] The Importance of Urban Habitat Connectivity and Influence on Native Avian Species and Community Science

  In what ways do small-scale urban backyards contribute to local bird abundance and biodiversity? In what ways might these yards serve as an ‘extension’ of neighboring native forest areas? This project ...

  Citation × Citation Citation Abstract Copy Title: The Importance of Urban Habitat Connectivity and Influence on Native Avian Species and Community Science Author: Gulick, Kristen S. Year: 2017 In what ways do small-scale urban backyards contribute to local bird abundance and biodiversity? In what ways might these yards serve as an ‘extension’ of neighboring native forest areas? This project investigates the contribution that a group of backyards, certified through the Backyard Habitat Certification Program, have in the suburb of Hillsdale, Oregon, which is adjacent to the natural area of Keller Woodland. Backyard owners functioning as citizen or community scientists assisted with conducting residential bird point-counts once a week in each backyard and the natural area. Counts were done for a total of 8 weeks during nesting season to better understand how backyard habitat restoration might affect their habitat especially when in close proximity to a natural area. The goal of the project was to help better understand the beneficial effects of urban gardening using native plants and diverse vegetation structure as this relates to bird species richness, and to explore the importance of community scientist contributions. Although the sample size was small, no significant trends were found, but the involvement of community scientists indicated increased skill, depth of understanding, and increased motivation for all participating backyard habitat owners. More backyards are needed for future research and extension into lower-income neighborhoods would be very beneficial to increase awareness of urban habitat connectivity and the diversity seen in backyard environmental characteristics and yard owner backyard habitat knowledge. A larger sample size could reveal correlations and provide a greater significance in data findings for bird abundance and diversity. A logical extension of this project would be to investigate food-web effects, specifically avian prey species, and smaller green-spaces that are often present in urban neighborhoods in addition to the large green-spaces. Authors: Kristen S. Gulick, Marion Dresner, Nikkie West Presenter: Kristen S. Gulick Title: The Importance of Urban Habitat Connectivity and Influence on Native Avian Species and Community Science Author: Gulick, Kristen S. Year: 2017 In what ways do small-scale urban backyards contribute to local bird abundance and biodiversity? In what ways might these yards serve as an ‘extension’ of neighboring native forest areas? This project investigates the contribution that a group of backyards, certified through the Backyard Habitat Certification Program, have in the suburb of Hillsdale, Oregon, which is adjacent to the natural area of Keller Woodland. Backyard owners functioning as citizen or community scientists assisted with conducting residential bird point-counts once a week in each backyard and the natural area. Counts were done for a total of 8 weeks during nesting season to better understand how backyard habitat restoration might affect their habitat especially when in close proximity to a natural area. The goal of the project was to help better understand the beneficial effects of urban gardening using native plants and diverse vegetation structure as this relates to bird species richness, and to explore the importance of community scientist contributions. Although the sample size was small, no significant trends were found, but the involvement of community scientists indicated increased skill, depth of understanding, and increased motivation for all participating backyard habitat owners. More backyards are needed for future research and extension into lower-income neighborhoods would be very beneficial to increase awareness of urban habitat connectivity and the diversity seen in backyard environmental characteristics and yard owner backyard habitat knowledge. A larger sample size could reveal correlations and provide a greater significance in data findings for bird abundance and diversity. A logical extension of this project would be to investigate food-web effects, specifically avian prey species, and smaller green-spaces that are often present in urban neighborhoods in addition to the large green-spaces. Authors: Kristen S. Gulick, Marion Dresner, Nikkie West Presenter: Kristen S. Gulick Close

• 4. [Article] Using Critical Physical Geography to Map the Unintended Consequences of Conservation Management Programs

  A variety of conservation trends have gained and lost favor throughout the years in agriculture, with U.S. Farm Bills often influencing what conservation practices are implemented by farming communities ...

  Citation × Citation Citation Abstract Copy Title: Using Critical Physical Geography to Map the Unintended Consequences of Conservation Management Programs Author: Malone, Melanie Year: 2017 A variety of conservation trends have gained and lost favor throughout the years in agriculture, with U.S. Farm Bills often influencing what conservation practices are implemented by farming communities throughout the U.S. This dissertation focuses on the unintended consequences of conservation management practices in the Fifteenmile Watershed of Wasco County, Oregon. Specifically, I seek to address how farmer enrollment in various conservation techniques, loosely defined as no-till agriculture, has affected soil and water quality through the increased use of herbicide, and subsequently rendered ecological and human health vulnerable. Using a critical physical geography framework, I address both the biophysical factors and social structures that have co-produced changes in soil and water quality in the study area of this research through intensive physical field data collection, spatial analysis, social surveys, and interviews. I also demonstrate how three neoliberal sets of processes: market-friendly reregulation; state rollback and deregulation; and the creation of self-sufficient individuals and communities, have transformed the human socio-environmental relationship to agriculture. These processes have had significant effects on the policies governing how soil and water quality are managed on both a state and national level, and have created a dependence on enrollment in conservation practices that may ultimately prove counterproductive for long term goals of environmental protection and sustainability. Title: Using Critical Physical Geography to Map the Unintended Consequences of Conservation Management Programs Author: Malone, Melanie Year: 2017 A variety of conservation trends have gained and lost favor throughout the years in agriculture, with U.S. Farm Bills often influencing what conservation practices are implemented by farming communities throughout the U.S. This dissertation focuses on the unintended consequences of conservation management practices in the Fifteenmile Watershed of Wasco County, Oregon. Specifically, I seek to address how farmer enrollment in various conservation techniques, loosely defined as no-till agriculture, has affected soil and water quality through the increased use of herbicide, and subsequently rendered ecological and human health vulnerable. Using a critical physical geography framework, I address both the biophysical factors and social structures that have co-produced changes in soil and water quality in the study area of this research through intensive physical field data collection, spatial analysis, social surveys, and interviews. I also demonstrate how three neoliberal sets of processes: market-friendly reregulation; state rollback and deregulation; and the creation of self-sufficient individuals and communities, have transformed the human socio-environmental relationship to agriculture. These processes have had significant effects on the policies governing how soil and water quality are managed on both a state and national level, and have created a dependence on enrollment in conservation practices that may ultimately prove counterproductive for long term goals of environmental protection and sustainability. Close

• 5. [Article] Advancing Rationality with Sustainability: An Analysis of Agent-Based Simulation

  Today, falling trends of species and ecosystem in the world due to overconsumption and destruction of natural resources are at critical levels. It is vital for humanity to operate with sustainable and ...

  Citation × Citation Citation Abstract Copy Title: Advancing Rationality with Sustainability: An Analysis of Agent-Based Simulation Author: Tanrikulu, Osman Goktug Year: 2017 Today, falling trends of species and ecosystem in the world due to overconsumption and destruction of natural resources are at critical levels. It is vital for humanity to operate with sustainable and resilient modes of production and consumption. In this regard, this paper examines the basic premise of rationality and introduces sustainability as an advancement to the theoretical concept of rationality. Thus, a rational mindset and a sustainable mindset are compared under depletion of environmental resources. The understanding of rationality in the analysis is based on Garett Hardin’s (1968) ‘the tragedy of the commons’ model, in which actors are self-interested and individualistic while seeking resources. Conversely, a sustainable mindset acknowledges environmental limitations and takes action accordingly. By utilizing agent-based modeling, both rational and sustainable mindsets are modeled, and their relative behavior are put into action in computer simulation. The results reveal that the basic understanding of rationality is not always going to maximize the utility of agents. Instead, there may be environmental conditions where having a sustainable mindset generates more wealth. In a scenario of resource depletion, the chances of survival decrease for rational agents. Their situation is exacerbated if their level of greed increases. However, the sustainable agents continue making stable wealth even with limited environmental resources. Rational actors must develop a sustainable mindset in order to acclimatize themselves to environmental deterioration. Title: Advancing Rationality with Sustainability: An Analysis of Agent-Based Simulation Author: Tanrikulu, Osman Goktug Year: 2017 Today, falling trends of species and ecosystem in the world due to overconsumption and destruction of natural resources are at critical levels. It is vital for humanity to operate with sustainable and resilient modes of production and consumption. In this regard, this paper examines the basic premise of rationality and introduces sustainability as an advancement to the theoretical concept of rationality. Thus, a rational mindset and a sustainable mindset are compared under depletion of environmental resources. The understanding of rationality in the analysis is based on Garett Hardin’s (1968) ‘the tragedy of the commons’ model, in which actors are self-interested and individualistic while seeking resources. Conversely, a sustainable mindset acknowledges environmental limitations and takes action accordingly. By utilizing agent-based modeling, both rational and sustainable mindsets are modeled, and their relative behavior are put into action in computer simulation. The results reveal that the basic understanding of rationality is not always going to maximize the utility of agents. Instead, there may be environmental conditions where having a sustainable mindset generates more wealth. In a scenario of resource depletion, the chances of survival decrease for rational agents. Their situation is exacerbated if their level of greed increases. However, the sustainable agents continue making stable wealth even with limited environmental resources. Rational actors must develop a sustainable mindset in order to acclimatize themselves to environmental deterioration. Close

• 6. [Article] Anthropogenic Effects on the Fouling Community: Impacts of Biological Invasions and Anthropogenic Structures on Community Structure

  Coastal anthropogenic infrastructure has significantly modified nearshore environments. Because these structures often have a strong association with shipping as would be found in ports and harbors, they ...

  Citation × Citation Citation Abstract Copy Title: Anthropogenic Effects on the Fouling Community: Impacts of Biological Invasions and Anthropogenic Structures on Community Structure Author: McClees, Whitney Elizabeth Year: 2017 Coastal anthropogenic infrastructure has significantly modified nearshore environments. Because these structures often have a strong association with shipping as would be found in ports and harbors, they have been identified as invasion hotspots. Due to propagule pressure from shipping and recreational boating and suitable uncolonized substrate that provides a refuge from native predators, a greater number of non-native species have been found on these structures compared to nearby natural substrate. The mechanisms that limit the spread of non-native species from anthropogenic structures to natural substrate have been explored for several taxa at a species-specific level, but less so from an overall community perspective. Predation has been identified as one of the biotic interactions limiting invasion success. In addition to predation, dispersal ability may also prevent the spread of non-native species from anthropogenic structures to natural substrate. This thesis addresses how these two mechanisms interact to limit the spread of non-native species from anthropogenic structures to natural substrate and how that alters overall community composition. I aimed to explore differences between communities inside and outside of a marina and determine the extent to which predator and dispersal limitation were structuring these communities. I used a three-factor design, deploying seven unglazed ceramic tiles per each treatment combination of 1) in versus outside a marina in Yaquina Bay, Oregon; 2) cage keeping out predators greater than the mesh size, no cage, or partial cage; 3) fixed near the substrata (benthic) versus suspended 1 meter below the surface. I also transplanted caged, suspended tiles of either adults or recruits from inside the marina to benthic and suspended caging treatments outside of the marina. These tiles allowed me to examine predation when dispersal limitation was not a factor for the community inside the marina, i.e. what happens to both recruits and adults if they can get outside of the marina. I found that the communities inside and outside of the marina were different and the data suggest that both predation and dispersal limitation interact to limit the spread of non-native species. Additionally, I found that mesopredators that could fit through the caging may be influencing predation results and community structure. This research addresses gaps in scientific knowledge regarding the mechanisms that prevent or facilitate the spread of non-native species. Future work could include the further exploration of mesopredation as an important factor in limiting the spread of non-native species and exploring dispersal limitation more in depth as well as broadening the geographic scope to see if the same trends hold true across bays and bioregions. Title: Anthropogenic Effects on the Fouling Community: Impacts of Biological Invasions and Anthropogenic Structures on Community Structure Author: McClees, Whitney Elizabeth Year: 2017 Coastal anthropogenic infrastructure has significantly modified nearshore environments. Because these structures often have a strong association with shipping as would be found in ports and harbors, they have been identified as invasion hotspots. Due to propagule pressure from shipping and recreational boating and suitable uncolonized substrate that provides a refuge from native predators, a greater number of non-native species have been found on these structures compared to nearby natural substrate. The mechanisms that limit the spread of non-native species from anthropogenic structures to natural substrate have been explored for several taxa at a species-specific level, but less so from an overall community perspective. Predation has been identified as one of the biotic interactions limiting invasion success. In addition to predation, dispersal ability may also prevent the spread of non-native species from anthropogenic structures to natural substrate. This thesis addresses how these two mechanisms interact to limit the spread of non-native species from anthropogenic structures to natural substrate and how that alters overall community composition. I aimed to explore differences between communities inside and outside of a marina and determine the extent to which predator and dispersal limitation were structuring these communities. I used a three-factor design, deploying seven unglazed ceramic tiles per each treatment combination of 1) in versus outside a marina in Yaquina Bay, Oregon; 2) cage keeping out predators greater than the mesh size, no cage, or partial cage; 3) fixed near the substrata (benthic) versus suspended 1 meter below the surface. I also transplanted caged, suspended tiles of either adults or recruits from inside the marina to benthic and suspended caging treatments outside of the marina. These tiles allowed me to examine predation when dispersal limitation was not a factor for the community inside the marina, i.e. what happens to both recruits and adults if they can get outside of the marina. I found that the communities inside and outside of the marina were different and the data suggest that both predation and dispersal limitation interact to limit the spread of non-native species. Additionally, I found that mesopredators that could fit through the caging may be influencing predation results and community structure. This research addresses gaps in scientific knowledge regarding the mechanisms that prevent or facilitate the spread of non-native species. Future work could include the further exploration of mesopredation as an important factor in limiting the spread of non-native species and exploring dispersal limitation more in depth as well as broadening the geographic scope to see if the same trends hold true across bays and bioregions. Close

• 7. [Article] Effects of Antibiotic Mixtures across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations

  Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, ...

  Citation × Citation Citation Abstract Copy Title: Effects of Antibiotic Mixtures across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations Author: Teixeira, Jaclyn Rebecca Year: 2016 Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, only fairly recent efforts have examined the potential impacts of these drugs on non-target organisms. The antibiotics sulfamethoxazole and trimethoprim, often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 700-800 ng/L each. Toxic effects of these drugs have been identified in freshwater organisms, with synergistic effects observed in short-term studies of mixtures of the two; however, little research has examined possible sub-lethal and longer-term effects of antibiotics in environmentally-relevant mixture concentrations on marine organisms. I examined the long-term effects of mixtures of these two antibiotics in species of a marine system: marine microalgal species, and marine mussels, to determine whether the levels currently present in waterways affect organism health and reproduction. Microalgal species may be among the most sensitive organisms to pharmaceutical contaminants based on ecotoxicity research. I exposed three species of marine microalgae (Isochrysis galbana, Chaetoceros neogracile, and Nannochloropsis oculata) to environmentally-relevant mixtures of sulfamethoxazole and trimethoprim and examined their three-week growth rates. I found that for each species, the antibiotic treatments significantly suppressed algal growth. Specifically, I found that sulfamethoxazole was a driving factor in suppression of C. neogracile and I. galbana growth, while N. oculata responded more sensitively to a broader range of treatment mixture levels, which also included trimethoprim-only treatment groups and mixtures. These results on marine microalgae address critical data gaps, and identify the impacts of pharmaceuticals on marine primary producers, which could have direct ecosystem implications to higher trophic levels. Antibiotic pharmaceuticals can also affect marine mussel health, based on previous study of sub-cellular endpoints. I hypothesized that the important benthic foundational species, the Mytilus californianus mussel, would be significantly impacted by long-term 12-week exposure to environmentally-relevant concentrations and mixtures of sulfamethoxazole and trimethoprim. Specifically, I measured growth rate, feeding rate, condition index, and gonando-somatic index as indicators of whole-organism and reproductive health. Sulfamethoxazole concentrations, in particular, and trimethoprim to a lesser extent, suppressed mussel growth and significantly affected condition index and gonandosomatic index over time. The results of this study offer an understanding of how an intertidal system responds to chronic presence of antibiotic mixtures in the water, and a more complete picture of the environmental consequences of pharmaceutical contaminants released into marine ecosystems at ever-growing rates. Title: Effects of Antibiotic Mixtures across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations Author: Teixeira, Jaclyn Rebecca Year: 2016 Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, only fairly recent efforts have examined the potential impacts of these drugs on non-target organisms. The antibiotics sulfamethoxazole and trimethoprim, often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 700-800 ng/L each. Toxic effects of these drugs have been identified in freshwater organisms, with synergistic effects observed in short-term studies of mixtures of the two; however, little research has examined possible sub-lethal and longer-term effects of antibiotics in environmentally-relevant mixture concentrations on marine organisms. I examined the long-term effects of mixtures of these two antibiotics in species of a marine system: marine microalgal species, and marine mussels, to determine whether the levels currently present in waterways affect organism health and reproduction. Microalgal species may be among the most sensitive organisms to pharmaceutical contaminants based on ecotoxicity research. I exposed three species of marine microalgae (Isochrysis galbana, Chaetoceros neogracile, and Nannochloropsis oculata) to environmentally-relevant mixtures of sulfamethoxazole and trimethoprim and examined their three-week growth rates. I found that for each species, the antibiotic treatments significantly suppressed algal growth. Specifically, I found that sulfamethoxazole was a driving factor in suppression of C. neogracile and I. galbana growth, while N. oculata responded more sensitively to a broader range of treatment mixture levels, which also included trimethoprim-only treatment groups and mixtures. These results on marine microalgae address critical data gaps, and identify the impacts of pharmaceuticals on marine primary producers, which could have direct ecosystem implications to higher trophic levels. Antibiotic pharmaceuticals can also affect marine mussel health, based on previous study of sub-cellular endpoints. I hypothesized that the important benthic foundational species, the Mytilus californianus mussel, would be significantly impacted by long-term 12-week exposure to environmentally-relevant concentrations and mixtures of sulfamethoxazole and trimethoprim. Specifically, I measured growth rate, feeding rate, condition index, and gonando-somatic index as indicators of whole-organism and reproductive health. Sulfamethoxazole concentrations, in particular, and trimethoprim to a lesser extent, suppressed mussel growth and significantly affected condition index and gonandosomatic index over time. The results of this study offer an understanding of how an intertidal system responds to chronic presence of antibiotic mixtures in the water, and a more complete picture of the environmental consequences of pharmaceutical contaminants released into marine ecosystems at ever-growing rates. Close

• 8. [Article] Do Forest Commons Contribute to International Environmental Initiatives? A Socio-Ecological Analysis of Nepalese Forest Commons in view of REDD+

  Forests in developing countries have the potential to contribute to global efforts to mitigate climate change, promote biodiversity and support the livelihoods of rural, local people. Approximately one-fourth ...

  Citation × Citation Citation Abstract Copy Title: Do Forest Commons Contribute to International Environmental Initiatives? A Socio-Ecological Analysis of Nepalese Forest Commons in view of REDD+ Author: Luintel, Harisharan Year: 2016 Forests in developing countries have the potential to contribute to global efforts to mitigate climate change, promote biodiversity and support the livelihoods of rural, local people. Approximately one-fourth of such forests are under the control of local communities, which primarily manage forests for subsistence and to meet their livelihood needs. The trend of bottom-up community control is increasing through the adoption of decentralization reforms over the last 40 years. In contrast, the United Nations has introduced the top-down program, Reducing Emissions from Deforestation and Forest Degradation (REDD+) for the conservation and enhancement of forest carbon and the sustainable management of forest in developing countries. REDD+ incentivizes forest-managing communities to sequester carbon and reduce emissions. REDD+ has created hope for managing forests to mitigate climate change and has created fear that the new initiative may not be effective and may not ensure continuing forest-managing community benefits. However, little research has been conducted to answer these concerns. By taking nationally representative data from Nepalese community-managed forests (“forest commons"), I bring insights into whether and how these forests can contribute to REDD+ initiatives, particularly as they relate to carbon sequestration, biodiversity, equity in benefit sharing and collective action. My results indicated the highly variable carbon and biodiversity in the forest plots across the country, depicting the availability of space for additional growth in carbon storage and biodiversity conservation. My results also reflect the complex and varied relationships of carbon with different indices of biodiversity at the national level, across geographic and topographic regions, and in forests with varying canopy covers. Weak positive relationships between carbon sequestration and biodiversity conservation indicate the possibility of synergies between carbon-forestry and biodiversity conservation. I also found that the formal community forestry program (CFP) has clearly positive impacts on biodiversity conservation and household-level equity in benefit sharing and a negative impact on carbon sequestration at the national level. However, disaggregated results of impacts of CFP on biodiversity, carbon and equity across geography, topography, forest quality and social groups display mixed results i.e., either positive or negative or neutral. I also identified that different drivers of collective action have different (i.e., positive, neutral, and negative) associations with carbon sequestration, which either supports or challenges established knowledge. In aggregate, my research indicates the potential of contribution by forest commons, and specially the CFP, to global environmental initiatives such as REDD+. It suggests that targeted, dedicated policies and programs to increase carbon sequestration, biodiversity conservation and foster equity and collective actions are critical. In addition, my results also contribute to the growing literature on socio-ecological implications of forest commons that demonstrated the need of interdisciplinary research to understand human-nature relationships in the changing context. Title: Do Forest Commons Contribute to International Environmental Initiatives? A Socio-Ecological Analysis of Nepalese Forest Commons in view of REDD+ Author: Luintel, Harisharan Year: 2016 Forests in developing countries have the potential to contribute to global efforts to mitigate climate change, promote biodiversity and support the livelihoods of rural, local people. Approximately one-fourth of such forests are under the control of local communities, which primarily manage forests for subsistence and to meet their livelihood needs. The trend of bottom-up community control is increasing through the adoption of decentralization reforms over the last 40 years. In contrast, the United Nations has introduced the top-down program, Reducing Emissions from Deforestation and Forest Degradation (REDD+) for the conservation and enhancement of forest carbon and the sustainable management of forest in developing countries. REDD+ incentivizes forest-managing communities to sequester carbon and reduce emissions. REDD+ has created hope for managing forests to mitigate climate change and has created fear that the new initiative may not be effective and may not ensure continuing forest-managing community benefits. However, little research has been conducted to answer these concerns. By taking nationally representative data from Nepalese community-managed forests (“forest commons"), I bring insights into whether and how these forests can contribute to REDD+ initiatives, particularly as they relate to carbon sequestration, biodiversity, equity in benefit sharing and collective action. My results indicated the highly variable carbon and biodiversity in the forest plots across the country, depicting the availability of space for additional growth in carbon storage and biodiversity conservation. My results also reflect the complex and varied relationships of carbon with different indices of biodiversity at the national level, across geographic and topographic regions, and in forests with varying canopy covers. Weak positive relationships between carbon sequestration and biodiversity conservation indicate the possibility of synergies between carbon-forestry and biodiversity conservation. I also found that the formal community forestry program (CFP) has clearly positive impacts on biodiversity conservation and household-level equity in benefit sharing and a negative impact on carbon sequestration at the national level. However, disaggregated results of impacts of CFP on biodiversity, carbon and equity across geography, topography, forest quality and social groups display mixed results i.e., either positive or negative or neutral. I also identified that different drivers of collective action have different (i.e., positive, neutral, and negative) associations with carbon sequestration, which either supports or challenges established knowledge. In aggregate, my research indicates the potential of contribution by forest commons, and specially the CFP, to global environmental initiatives such as REDD+. It suggests that targeted, dedicated policies and programs to increase carbon sequestration, biodiversity conservation and foster equity and collective actions are critical. In addition, my results also contribute to the growing literature on socio-ecological implications of forest commons that demonstrated the need of interdisciplinary research to understand human-nature relationships in the changing context. Close

• 9. [Article] Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary

  In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, ...

  Citation × Citation Citation Abstract Copy Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Close