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• 1. [Article] Climate Change Effects on Northern Great Lake (USA) Forests: A Case for Preserving Diversity

  Under business as usual (BAU) management, stresses posed by climate change may exceed the ability of Great Lake forests to adapt. Temperature and precipitation projections in the Great Lakes region are ...

  Citation × Citation Citation Abstract Copy Title: Climate Change Effects on Northern Great Lake (USA) Forests: A Case for Preserving Diversity Author: Duveneck, Matthew Joshua, Scheller, Robert M., White, Mark A., Handler, Stephen D., Ravenscroft, Catherine Year: 2014 Under business as usual (BAU) management, stresses posed by climate change may exceed the ability of Great Lake forests to adapt. Temperature and precipitation projections in the Great Lakes region are expected to change forest tree species composition and productivity. It is unknown how a change in productivity and/or tree species diversity due to climate change will affect the relationship between diversity and productivity. We assessed how forests in two landscapes (i.e., northern lower Michigan and northeastern Minnesota, USA) would respond to climate change and explored the diversityproductivity relationship under climate change. In addition, we explored how tree species diversity varied across landscapes by soil type, climate, and management. We used a spatially dynamic forest ecosystem model, LANDIS-II, to simulate BAU forest management under three climate scenarios (current climate, low emissions, and high emissions) in each landscape. We found a positive relationship between diversity and productivity only under a high emissions future as productivity declined. Within landscapes, climate change simulations resulted in the highest diversity in the coolest climate regions and lowest diversity in the warmest climate region in Minnesota and Michigan, respectively. Simulated productivity declined in both landscapes under the high emissions climate scenario as species such as balsam fir (Abies balsamea) declined in abundance. In the Great Lakes region, a high emissions future may decrease forest productivity creating a more positive relationship between diversity and productivity. Maintaining a diversity of tree species may become increasingly important to maintain the adaptive capacity of forests. Title: Climate Change Effects on Northern Great Lake (USA) Forests: A Case for Preserving Diversity Author: Duveneck, Matthew Joshua, Scheller, Robert M., White, Mark A., Handler, Stephen D., Ravenscroft, Catherine Year: 2014 Under business as usual (BAU) management, stresses posed by climate change may exceed the ability of Great Lake forests to adapt. Temperature and precipitation projections in the Great Lakes region are expected to change forest tree species composition and productivity. It is unknown how a change in productivity and/or tree species diversity due to climate change will affect the relationship between diversity and productivity. We assessed how forests in two landscapes (i.e., northern lower Michigan and northeastern Minnesota, USA) would respond to climate change and explored the diversityproductivity relationship under climate change. In addition, we explored how tree species diversity varied across landscapes by soil type, climate, and management. We used a spatially dynamic forest ecosystem model, LANDIS-II, to simulate BAU forest management under three climate scenarios (current climate, low emissions, and high emissions) in each landscape. We found a positive relationship between diversity and productivity only under a high emissions future as productivity declined. Within landscapes, climate change simulations resulted in the highest diversity in the coolest climate regions and lowest diversity in the warmest climate region in Minnesota and Michigan, respectively. Simulated productivity declined in both landscapes under the high emissions climate scenario as species such as balsam fir (Abies balsamea) declined in abundance. In the Great Lakes region, a high emissions future may decrease forest productivity creating a more positive relationship between diversity and productivity. Maintaining a diversity of tree species may become increasingly important to maintain the adaptive capacity of forests. Close

• 2. [Article] Increased Habitat Connectivity Homogenizes Freshwater Communities: Historical and Landscape Perspectives

  Increases in habitat connectivity can have consequences for taxonomic, functional, and genetic diversity of communities. Previously isolated aquatic habitats were connected with canals and pipelines in ...

  Citation × Citation Citation Abstract Copy Title: Increased Habitat Connectivity Homogenizes Freshwater Communities: Historical and Landscape Perspectives Author: Strecker, Angela L., Brittain, Jeffrey Thomas Year: 2017 Increases in habitat connectivity can have consequences for taxonomic, functional, and genetic diversity of communities. Previously isolated aquatic habitats were connected with canals and pipelines in the largest water development project in the US history, the Columbia Basin Project (CBP; eastern Washington, USA), which also altered environmental conditions; however, the ecological consequences are largely unknown. Using a historical dataset, we examined long-term patterns in zooplankton communities, water chemistry and clarity, testing the hypothesis that increased connectivity will result in taxonomic homogenization. Further, we tested contemporary drivers of communities using a comprehensive set of environmental and landscape variables. Waterbodies were sampled for zooplankton community composition as well as physical and chemical variables inside and outside the CBP using methods consistent with historical studies. We found significant declines in salinity inside the CBP, whereas changes in water clarity were prevalent across all waterbodies. Increased connectivity via canals homogenized zooplankton communities over time, as well as increasing regional richness. Other long-term changes in zooplankton communities may be related to climate change, invasive species, and land-use changes. Synthesis and applications. Though canals may offer species spatial refugia, homogenization may decrease resilience to environmental stressors. These new hybrid aquatic landscapes, or hydroscapes, should be considered carefully in future water development, including specific plans for monitoring of species and environmental conditions, as well as mitigation of undesirable conditions and/or non-native species. Title: Increased Habitat Connectivity Homogenizes Freshwater Communities: Historical and Landscape Perspectives Author: Strecker, Angela L., Brittain, Jeffrey Thomas Year: 2017 Increases in habitat connectivity can have consequences for taxonomic, functional, and genetic diversity of communities. Previously isolated aquatic habitats were connected with canals and pipelines in the largest water development project in the US history, the Columbia Basin Project (CBP; eastern Washington, USA), which also altered environmental conditions; however, the ecological consequences are largely unknown. Using a historical dataset, we examined long-term patterns in zooplankton communities, water chemistry and clarity, testing the hypothesis that increased connectivity will result in taxonomic homogenization. Further, we tested contemporary drivers of communities using a comprehensive set of environmental and landscape variables. Waterbodies were sampled for zooplankton community composition as well as physical and chemical variables inside and outside the CBP using methods consistent with historical studies. We found significant declines in salinity inside the CBP, whereas changes in water clarity were prevalent across all waterbodies. Increased connectivity via canals homogenized zooplankton communities over time, as well as increasing regional richness. Other long-term changes in zooplankton communities may be related to climate change, invasive species, and land-use changes. Synthesis and applications. Though canals may offer species spatial refugia, homogenization may decrease resilience to environmental stressors. These new hybrid aquatic landscapes, or hydroscapes, should be considered carefully in future water development, including specific plans for monitoring of species and environmental conditions, as well as mitigation of undesirable conditions and/or non-native species. Close

• 3. [Article] Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon

  The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed ...

  Citation × Citation Citation Abstract Copy Title: Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon Author: Foster, Susan Ann Year: 1992 The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops. Title: Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon Author: Foster, Susan Ann Year: 1992 The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops. Close

• 4. [Article] Quantifying Resilience of Multiple Ecosystem Services and Biodiversity in a Temperate Forest Landscape

  Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. ...

  Citation × Citation Citation Abstract Copy Title: Quantifying Resilience of Multiple Ecosystem Services and Biodiversity in a Temperate Forest Landscape Author: Cantarello, Elena, Newton, Adrian C., Martin, Phillip A., Evans, Paul M., Gosal, Arjan, Lucash, Melissa S. Year: 2017 Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. Faced with novel disturbances, forests may be able to sustain existing ecosystem services and biodiversity by exhibiting resilience, or alternatively these attributes may undergo either a linear or nonlinear decline. Here we provide a novel quantitative approach for assessing forest resilience that focuses on three components of resilience, namely resistance, recovery, and net change, using a spatially explicit model of forest dynamics. Under the pulse set scenarios, we explored the resilience of nine ecosystem services and four biodiversity measures following a one-off disturbance applied to an increasing percentage of forest area. Under the pulse + press set scenarios, the six disturbance intensities explored during the pulse set were followed by a continuous disturbance. We detected thresholds in net change under pulse + press scenarios for the majority of the ecosystem services and biodiversity measures, which started to decline sharply when disturbance affected >40% of the landscape. Thresholds in net change were not observed under the pulse scenarios, with the exception of timber volume and ground flora species richness. Thresholds were most pronounced for aboveground biomass, timber volume with respect to the ecosystem services, and ectomycorrhizal fungi and ground flora species richness with respect to the biodiversity measures. Synthesis and applications. The approach presented here illustrates how the multidimensionality of stability research in ecology can be addressed and how forest resilience can be estimated in practice. Managers should adopt specific management actions to support each of the three components of resilience separately, as these may respond differently to disturbance. In addition, management interventions aiming to deliver resilience should incorporate an assessment of both pulse and press disturbances to ensure detection of threshold responses to disturbance, so that appropriate management interventions can be identified. Title: Quantifying Resilience of Multiple Ecosystem Services and Biodiversity in a Temperate Forest Landscape Author: Cantarello, Elena, Newton, Adrian C., Martin, Phillip A., Evans, Paul M., Gosal, Arjan, Lucash, Melissa S. Year: 2017 Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. Faced with novel disturbances, forests may be able to sustain existing ecosystem services and biodiversity by exhibiting resilience, or alternatively these attributes may undergo either a linear or nonlinear decline. Here we provide a novel quantitative approach for assessing forest resilience that focuses on three components of resilience, namely resistance, recovery, and net change, using a spatially explicit model of forest dynamics. Under the pulse set scenarios, we explored the resilience of nine ecosystem services and four biodiversity measures following a one-off disturbance applied to an increasing percentage of forest area. Under the pulse + press set scenarios, the six disturbance intensities explored during the pulse set were followed by a continuous disturbance. We detected thresholds in net change under pulse + press scenarios for the majority of the ecosystem services and biodiversity measures, which started to decline sharply when disturbance affected >40% of the landscape. Thresholds in net change were not observed under the pulse scenarios, with the exception of timber volume and ground flora species richness. Thresholds were most pronounced for aboveground biomass, timber volume with respect to the ecosystem services, and ectomycorrhizal fungi and ground flora species richness with respect to the biodiversity measures. Synthesis and applications. The approach presented here illustrates how the multidimensionality of stability research in ecology can be addressed and how forest resilience can be estimated in practice. Managers should adopt specific management actions to support each of the three components of resilience separately, as these may respond differently to disturbance. In addition, management interventions aiming to deliver resilience should incorporate an assessment of both pulse and press disturbances to ensure detection of threshold responses to disturbance, so that appropriate management interventions can be identified. Close

• 5. [Article] Final Report: Evaluation of the Morphoedaphic Index and Sediment Diatoms for Inference of Pre-European Settlement Total Phosphorus Concentration in EPA Region 10 Lakes

  Water quality in many Northwest lakes has declined over the past century due, in part, to increased anthropogenic nutrient loading (Edmonson and Lehman, 1981). Under the Clean Water Act, resource managers ...

  Citation × Citation Citation Abstract Copy Title: Final Report: Evaluation of the Morphoedaphic Index and Sediment Diatoms for Inference of Pre-European Settlement Total Phosphorus Concentration in EPA Region 10 Lakes Author: Miller, Rich, Hook, Aaron, Petersen, Richard, Sytsma, Mark D. Year: 2005 Water quality in many Northwest lakes has declined over the past century due, in part, to increased anthropogenic nutrient loading (Edmonson and Lehman, 1981). Under the Clean Water Act, resource managers such as the Washington Department of Ecology, Oregon Department of Environmental Quality, and tribes are responsible for restoring and protecting the integrity of these waters. Targets for restoration or criteria for impairment are not well defined, however, and may naturally vary by geology, hydrology, morphometry, and climate. One way to determine whether lakes are impaired and to identify restoration targets is to assess lake reference conditions (EPA 2000). Reference conditions are the water quality conditions that would exist in the absence of anthropogenic perturbation. Reference conditions are not nutrient criteria but can be useful in establishing realistic criteria that reflect natural regional variations in water quality. The EPA suggests three general approaches for assessing reference conditions (EPA 2000): Observation of reference lake or entire lake population distributions Paleolimnological reconstruction of past conditions. Estimation of past conditions from mass balance nutrient loading models, morphoedaphic index models, or other mathematical models. The lake population distribution approach involves observing data from either a set of lakes that are relatively unimpacted or from a random selection of all lakes in a region. The lower percentile of each population distribution is assumed to represent reference conditions. The lower 75th percentile of the relatively unimpacted population distribution has been used as a cutoff for reference conditions while the 25th percentile has been used for the lake population distribution as a whole. The Washington Department of Ecology has used this approach to develop phosphorus criteria (Moore and Hicks 2004). This approach assumes that the percentiles in a distribution represent reference conditions. Paleolimnological models are based on the observation that sediments continually incorporate information from the overlying water column and that sediment cores provide a history of past conditions. Sedimented diatom-based water quality reconstructions are based on two main observations (Hall and Smol 1992): (1) individual diatom species have restricted nutrient requirements and are sensitive indicators of lake trophic status, and (2) the cell walls of diatoms are abundant and well preserved in most lake sediments and can usually be identified to a specific or subspecific level. Weighted-averaging and calibration statistical models have been used to relate sediment surface diatom assemblages to contemporary water quality parameters. These speciesenvironment relationships, known as transfer functions, can then be used to infer past water quality conditions from diatom remains preserved deep in sediments. This approach has been successfully applied in several geographic regions including the northeastern United States (Dixit et al. 1999), Minnesota (Ramstack et al. 2003), and British Columbia (Reavie et al. 1995). The morphoedaphic index (MEI) was originally developed to predict fisheries yield in lakes based on lake morphometry and alkalinity or conductivity (Ryder 1965). Vighi and Chiaudani (1985) suggested the utility of the index for inferring natural background phosphorus levels in lakes. Their major assumption was that human activities have not altered lake morphometry and ionic strength to the degree that the same activities have increased nutrient loading. While the model is simple, it has been successfully used in to infer background phosphorus concentration in Midwest lakes (Ramstack et al. 2003). We used the MEI and the sedimented diatom total phosphorus inference models to assess lake reference conditions for Puget Lowlands and Northern Willamette Valley Ecoregion Lakes. Title: Final Report: Evaluation of the Morphoedaphic Index and Sediment Diatoms for Inference of Pre-European Settlement Total Phosphorus Concentration in EPA Region 10 Lakes Author: Miller, Rich, Hook, Aaron, Petersen, Richard, Sytsma, Mark D. Year: 2005 Water quality in many Northwest lakes has declined over the past century due, in part, to increased anthropogenic nutrient loading (Edmonson and Lehman, 1981). Under the Clean Water Act, resource managers such as the Washington Department of Ecology, Oregon Department of Environmental Quality, and tribes are responsible for restoring and protecting the integrity of these waters. Targets for restoration or criteria for impairment are not well defined, however, and may naturally vary by geology, hydrology, morphometry, and climate. One way to determine whether lakes are impaired and to identify restoration targets is to assess lake reference conditions (EPA 2000). Reference conditions are the water quality conditions that would exist in the absence of anthropogenic perturbation. Reference conditions are not nutrient criteria but can be useful in establishing realistic criteria that reflect natural regional variations in water quality. The EPA suggests three general approaches for assessing reference conditions (EPA 2000): Observation of reference lake or entire lake population distributions Paleolimnological reconstruction of past conditions. Estimation of past conditions from mass balance nutrient loading models, morphoedaphic index models, or other mathematical models. The lake population distribution approach involves observing data from either a set of lakes that are relatively unimpacted or from a random selection of all lakes in a region. The lower percentile of each population distribution is assumed to represent reference conditions. The lower 75th percentile of the relatively unimpacted population distribution has been used as a cutoff for reference conditions while the 25th percentile has been used for the lake population distribution as a whole. The Washington Department of Ecology has used this approach to develop phosphorus criteria (Moore and Hicks 2004). This approach assumes that the percentiles in a distribution represent reference conditions. Paleolimnological models are based on the observation that sediments continually incorporate information from the overlying water column and that sediment cores provide a history of past conditions. Sedimented diatom-based water quality reconstructions are based on two main observations (Hall and Smol 1992): (1) individual diatom species have restricted nutrient requirements and are sensitive indicators of lake trophic status, and (2) the cell walls of diatoms are abundant and well preserved in most lake sediments and can usually be identified to a specific or subspecific level. Weighted-averaging and calibration statistical models have been used to relate sediment surface diatom assemblages to contemporary water quality parameters. These speciesenvironment relationships, known as transfer functions, can then be used to infer past water quality conditions from diatom remains preserved deep in sediments. This approach has been successfully applied in several geographic regions including the northeastern United States (Dixit et al. 1999), Minnesota (Ramstack et al. 2003), and British Columbia (Reavie et al. 1995). The morphoedaphic index (MEI) was originally developed to predict fisheries yield in lakes based on lake morphometry and alkalinity or conductivity (Ryder 1965). Vighi and Chiaudani (1985) suggested the utility of the index for inferring natural background phosphorus levels in lakes. Their major assumption was that human activities have not altered lake morphometry and ionic strength to the degree that the same activities have increased nutrient loading. While the model is simple, it has been successfully used in to infer background phosphorus concentration in Midwest lakes (Ramstack et al. 2003). We used the MEI and the sedimented diatom total phosphorus inference models to assess lake reference conditions for Puget Lowlands and Northern Willamette Valley Ecoregion Lakes. Close