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• 1. [Article] Efficacy of Plastic Mesh Tubes in Reducing Herbivory Damage by the Invasive Nutria (Myocastor coypus) in an Urban Restoration Site

  The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ...

  Citation × Citation Citation Abstract Copy Title: Efficacy of Plastic Mesh Tubes in Reducing Herbivory Damage by the Invasive Nutria (Myocastor coypus) in an Urban Restoration Site Author: Sheffels, Trevor R., Sytsma, Mark D., Carter, Jacoby, Taylor, Jimmy D. Year: 2014 The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria (Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological impacts in riparian and wetland habitats throughout its introduced range, and techniques are needed to reduce nutria herbivory damage to urban stream restoration projects. We assessed the efficacy of standard Vexar® plastic mesh tubes in reducing nutria herbivory damage to newly established woody plants. The study was conducted in winter-spring 2009 at Delta Ponds, a 60-ha urban waterway in Eugene, Oregon. Woody plants protected by Vexar® tubes demonstrated 100% survival over the 3-month initial establishment period, while only 17% of unprotected plantings survived. Nutria demonstrated a preference for black cottonwood(Populus balsamifera ssp trichocarpa) over red osier dogwood (Cornus sericea) and willow (Salix spp). Camera surveillance showed that nutria were more active in unprotected rather than protected treatments. Our results suggest that Vexar® plastic mesh tubing can be an effective short-term herbivory mitigation tool when habitat use by nutria is low. Additionally, planting functionally equivalent woody plant species that are less preferred by nutria, and other herbivores, may be another method for reducing herbivory and improving revegetation success. This study highlights the need to address potential wildlife damage conflicts in the planning process for stream restoration in urban landscapes. Title: Efficacy of Plastic Mesh Tubes in Reducing Herbivory Damage by the Invasive Nutria (Myocastor coypus) in an Urban Restoration Site Author: Sheffels, Trevor R., Sytsma, Mark D., Carter, Jacoby, Taylor, Jimmy D. Year: 2014 The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria (Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological impacts in riparian and wetland habitats throughout its introduced range, and techniques are needed to reduce nutria herbivory damage to urban stream restoration projects. We assessed the efficacy of standard Vexar® plastic mesh tubes in reducing nutria herbivory damage to newly established woody plants. The study was conducted in winter-spring 2009 at Delta Ponds, a 60-ha urban waterway in Eugene, Oregon. Woody plants protected by Vexar® tubes demonstrated 100% survival over the 3-month initial establishment period, while only 17% of unprotected plantings survived. Nutria demonstrated a preference for black cottonwood(Populus balsamifera ssp trichocarpa) over red osier dogwood (Cornus sericea) and willow (Salix spp). Camera surveillance showed that nutria were more active in unprotected rather than protected treatments. Our results suggest that Vexar® plastic mesh tubing can be an effective short-term herbivory mitigation tool when habitat use by nutria is low. Additionally, planting functionally equivalent woody plant species that are less preferred by nutria, and other herbivores, may be another method for reducing herbivory and improving revegetation success. This study highlights the need to address potential wildlife damage conflicts in the planning process for stream restoration in urban landscapes. Close

• 2. [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

• 3. [Image] Naetrocymbe punctiformis

  	Spores; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters.
  	Citation × Citation Citation Abstract Copy Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Spores; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Spores; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Close

• 4. [Image] Naetrocymbe punctiformis

  	Perithecia; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters.
  	Citation × Citation Citation Abstract Copy Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Perithecia; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Perithecia; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Close

• 5. [Image] Naetrocymbe punctiformis

  	Hymenium IKI; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters.
  	Citation × Citation Citation Abstract Copy Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Hymenium IKI; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Hymenium IKI; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Close

• 6. [Image] Naetrocymbe punctiformis

  	Hymenium; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters.
  	Citation × Citation Citation Abstract Copy Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Hymenium; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Hymenium; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Close

• 7. [Image] Naetrocymbe punctiformis

  	Habit; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters.
  	Citation × Citation Citation Abstract Copy Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Habit; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Title: Naetrocymbe punctiformis Author: McCune, Bruce Year: 2016 Habit; Habitat: Deciduous trees, shrub thickets, ash swamps; Location: Jackson-Frazier wetlands, Willamette Valley; Substrate: Bark, Fraxinus trunk; Elevation: 65 meters. Close

• 8. [Article] Constructed Wetland Suitability Analysis in Oregon

  51 pages

  Citation × Citation Citation Abstract Copy Title: Constructed Wetland Suitability Analysis in Oregon Author: Collins, Kyle Year: 2017 51 pages Title: Constructed Wetland Suitability Analysis in Oregon Author: Collins, Kyle Year: 2017 51 pages Close

• 9. [Article] Assessing Habitat Requirements of Pond-Breeding Amphibians in a Highly Urbanized Landscape:Implications for Management

  Management of urban aquatic habitats for native wildlife, such as amphibians, is an important contemporary goal for many municipalities. However, our understanding of how local and landscape characteristics ...

  Citation × Citation Citation Abstract Copy Title: Assessing Habitat Requirements of Pond-Breeding Amphibians in a Highly Urbanized Landscape:Implications for Management Author: Guderyahn, Laura B., Smithers, Ashley P., Mims, Meryl C. Year: 2016 Management of urban aquatic habitats for native wildlife, such as amphibians, is an important contemporary goal for many municipalities. However, our understanding of how local and landscape characteristics of urban aquatic habitat promote or inhibit amphibian occupancy and recruitment is limited. In this study, we examined amphibian community composition and occurrence patterns in ponds, wetlands, and swales of Gresham, Oregon. We collected occurrence data for five native amphibians: northwestern salamander (Ambystoma gracile), long-toed salamander (A. macrodactylum), Pacific chorus frog (Pseudacris regilla), northern red-legged frog (Rana aurora aurora), and rough-skinned newt (Taricha granulosa) as well as one non-native amphibian, the American bullfrog (Lithobates catesbeianus). One hundred sites were surveyed from 2007 to 2013. Local and landscape attributes were characterized for each site, and potential drivers of species occupancy were evaluated using a combination of multivariate approaches and generalized linear models. In general, percent impervious surface and distance to nearest forest patch, both associated with urbanization, were negatively correlated with site occupancy for all species. Non-native vegetation was also negatively associated with occupancy of three species (long-toed salamanders, Pacific chorus frogs, and northern red-legged frogs). In contrast, occupancy was positively correlated with pond depth and hydroperiod length for all species. We found evidence of two distinct groups of co-occurring amphibian species driven by habitat depth and hydroperiod. Finally, we report results of threshold analyses that examined species-specific habitat associations. This study describes urban habitat associations of a native amphibian community, identifies factors with positive, negative or mixed relationships with amphibian species, and is an important step in informing the management of urban aquatic habitat to promote persistence of native amphibians. Title: Assessing Habitat Requirements of Pond-Breeding Amphibians in a Highly Urbanized Landscape:Implications for Management Author: Guderyahn, Laura B., Smithers, Ashley P., Mims, Meryl C. Year: 2016 Management of urban aquatic habitats for native wildlife, such as amphibians, is an important contemporary goal for many municipalities. However, our understanding of how local and landscape characteristics of urban aquatic habitat promote or inhibit amphibian occupancy and recruitment is limited. In this study, we examined amphibian community composition and occurrence patterns in ponds, wetlands, and swales of Gresham, Oregon. We collected occurrence data for five native amphibians: northwestern salamander (Ambystoma gracile), long-toed salamander (A. macrodactylum), Pacific chorus frog (Pseudacris regilla), northern red-legged frog (Rana aurora aurora), and rough-skinned newt (Taricha granulosa) as well as one non-native amphibian, the American bullfrog (Lithobates catesbeianus). One hundred sites were surveyed from 2007 to 2013. Local and landscape attributes were characterized for each site, and potential drivers of species occupancy were evaluated using a combination of multivariate approaches and generalized linear models. In general, percent impervious surface and distance to nearest forest patch, both associated with urbanization, were negatively correlated with site occupancy for all species. Non-native vegetation was also negatively associated with occupancy of three species (long-toed salamanders, Pacific chorus frogs, and northern red-legged frogs). In contrast, occupancy was positively correlated with pond depth and hydroperiod length for all species. We found evidence of two distinct groups of co-occurring amphibian species driven by habitat depth and hydroperiod. Finally, we report results of threshold analyses that examined species-specific habitat associations. This study describes urban habitat associations of a native amphibian community, identifies factors with positive, negative or mixed relationships with amphibian species, and is an important step in informing the management of urban aquatic habitat to promote persistence of native amphibians. Close

• 10. [Article] Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon

  This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Close

• 11. [Article] Modeling Historic Columbia River Flood Impacts

  The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling ...

  Citation × Citation Citation Abstract Copy Title: Modeling Historic Columbia River Flood Impacts Author: Helaire, Lumas, Mahedy, Andrew, Talke, Stefan A., Jay, David A Year: 2014 The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19th century. In this research project we look at several river flow scenarios. We are interested in the interaction between river flow and ocean tides, how it has changed in the LCRE since the 19th century and how it affects the river physics. With the model, we focus on the following questions: How has the spatial structure of salinity changed since the 1890's? Has the salinity intrusion length increased or decreased? Is there a change in residual salinity in some of the bays in the estuary? How have changes to the bathymetric structure of the river affected salinity intrusion? For the same flow river flow, how have wetland inundation patterns changed? How have changes to the tidal prism ascertained from a temporal analysis of tidal records, affected the amount of land inundated in a tidal cycle and how long that land remains inundated? Initial results suggest that salinity intrusion patterns have shifted and that wetland inundation patterns have been impacted by the up to 10% increase in the estuary tidal range since the late 19th century. Title: Modeling Historic Columbia River Flood Impacts Author: Helaire, Lumas, Mahedy, Andrew, Talke, Stefan A., Jay, David A Year: 2014 The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19th century. In this research project we look at several river flow scenarios. We are interested in the interaction between river flow and ocean tides, how it has changed in the LCRE since the 19th century and how it affects the river physics. With the model, we focus on the following questions: How has the spatial structure of salinity changed since the 1890's? Has the salinity intrusion length increased or decreased? Is there a change in residual salinity in some of the bays in the estuary? How have changes to the bathymetric structure of the river affected salinity intrusion? For the same flow river flow, how have wetland inundation patterns changed? How have changes to the tidal prism ascertained from a temporal analysis of tidal records, affected the amount of land inundated in a tidal cycle and how long that land remains inundated? Initial results suggest that salinity intrusion patterns have shifted and that wetland inundation patterns have been impacted by the up to 10% increase in the estuary tidal range since the late 19th century. Close

• 12. [Article] Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon

  We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of ...

  Citation × Citation Citation Abstract Copy Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Close

• 13. [Article] Applications of Remote Sensing to the Study of Estuarine Physics: Suspended Sediment Dynamics in the Columbia River Estuary

  Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding ...

  Citation × Citation Citation Abstract Copy Title: Applications of Remote Sensing to the Study of Estuarine Physics: Suspended Sediment Dynamics in the Columbia River Estuary Author: Hudson, Austin Scott Year: 2014 Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding and consideration of this circulation is, therefore, vital in the proper management of these habitats. The aim of this study is to bring together theory and new satellite observations in the Columbia River Estuary to increase our understanding of estuarine circulation and transport. Surface reflectance measurements gathered by the Moderate Imaging Spectroradiometer (MODIS) are first compared to in situ observations to develop an empirical model for remotely derived surface turbidity. Results indicate that MODIS data significantly correlate with in situ measurements of turbidity throughout the CRE (R2 = 0.96). Remote estimates of turbidity are then used to explore the physical processes that drive their spatial distribution. Although the response to different hydrodynamic conditions varies throughout the system, global levels of turbidity are most sensitive to fluvial and tidal inputs and increase during spring tides and high river flow. As a result, the turbidity field has temporal cycles that are consistent with the frequency of these processes. The location of the estuarine turbidity maximum (ETM) is highly dynamic and typically migrates downstream as the tidal velocity or river flow increases. The ETM becomes trapped near the Megler Bridge (river kilometer 20), however, and the presence of strong topography in this region suggests there exists an interaction between bottom topography and sediment transport. A 2-D semi-analytical model, developed herein from the simplified Navier-Stokes equations, confirms that topographic features exhibit substantial influence on longitudinal turbidity distributions. The model considers the coupled, tidally-averaged velocity (composed of gravitational circulation, internal tidal asymmetry, and river flow) and salinity fields and assumes a condition of morphodynamic equilibrium to estimate the distribution of sediment for arbitrary channel configurations. Model simulations demonstrate that topographic highs tend to increase local seaward sediment fluxes, and that topographic lows increase local landward sediment fluxes. Sediment flux convergence near topographic highs compresses the local turbidity distribution, whereas flux divergence near topographic lows dilates the distribution and, under appropriate conditions, produces multiple ETMs. In summary a combination of the model and satellite data has given valuable new insights into the sediment dynamics of estuarine environments; in particular, both show that turbidity distribution and ETM location vary considerably with tidal and river flow conditions, fluctuating on a variety of timescales, and are heavily influenced by bottom topography. Title: Applications of Remote Sensing to the Study of Estuarine Physics: Suspended Sediment Dynamics in the Columbia River Estuary Author: Hudson, Austin Scott Year: 2014 Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding and consideration of this circulation is, therefore, vital in the proper management of these habitats. The aim of this study is to bring together theory and new satellite observations in the Columbia River Estuary to increase our understanding of estuarine circulation and transport. Surface reflectance measurements gathered by the Moderate Imaging Spectroradiometer (MODIS) are first compared to in situ observations to develop an empirical model for remotely derived surface turbidity. Results indicate that MODIS data significantly correlate with in situ measurements of turbidity throughout the CRE (R2 = 0.96). Remote estimates of turbidity are then used to explore the physical processes that drive their spatial distribution. Although the response to different hydrodynamic conditions varies throughout the system, global levels of turbidity are most sensitive to fluvial and tidal inputs and increase during spring tides and high river flow. As a result, the turbidity field has temporal cycles that are consistent with the frequency of these processes. The location of the estuarine turbidity maximum (ETM) is highly dynamic and typically migrates downstream as the tidal velocity or river flow increases. The ETM becomes trapped near the Megler Bridge (river kilometer 20), however, and the presence of strong topography in this region suggests there exists an interaction between bottom topography and sediment transport. A 2-D semi-analytical model, developed herein from the simplified Navier-Stokes equations, confirms that topographic features exhibit substantial influence on longitudinal turbidity distributions. The model considers the coupled, tidally-averaged velocity (composed of gravitational circulation, internal tidal asymmetry, and river flow) and salinity fields and assumes a condition of morphodynamic equilibrium to estimate the distribution of sediment for arbitrary channel configurations. Model simulations demonstrate that topographic highs tend to increase local seaward sediment fluxes, and that topographic lows increase local landward sediment fluxes. Sediment flux convergence near topographic highs compresses the local turbidity distribution, whereas flux divergence near topographic lows dilates the distribution and, under appropriate conditions, produces multiple ETMs. In summary a combination of the model and satellite data has given valuable new insights into the sediment dynamics of estuarine environments; in particular, both show that turbidity distribution and ETM location vary considerably with tidal and river flow conditions, fluctuating on a variety of timescales, and are heavily influenced by bottom topography. Close