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• 41. [Article] Monitoring design for riparian forests in the Pacific Northwest : research plan

  The goal of this project is to recommend a broadly-acceptale efficient and effective methodology for characterizing streamside riparian attributes in forested settings at the site grain for regional monitoring. ...

  Citation × Citation Citation Abstract Copy Title: Monitoring design for riparian forests in the Pacific Northwest : research plan Author: Bollman, Mike, National Health and Environmental Effects Laboratory., Oregon State University, Stepp, Jennifer, United States. Environmental Protection Agency. ǂb Office of Research and Development, United States. Forest Service, Barker, Jerry R., Bradshaw, Gay, Ringold, Paul L., Cline, Steven Paul, Carson, Ward, Dynamac Corporation, Fiorella, Maria R. The goal of this project is to recommend a broadly-acceptale efficient and effective methodology for characterizing streamside riparian attributes in forested settings at the site grain for regional monitoring. The authors consider monitoring design in the context of three interacting constraints: ecological functions, capabilities of technologies, and user needs. The focus is on fine grained remote methods. Comparison between candidate selected monitoring systems provides for an initial formulation of a monitoring design. A series of evaluations of these initial formulations provides for an initial recommendation. With the state's interest in the status of coastal fishes, and the programmatic interest of EPA's Western Ecology Division, the areas selected for study are in the Oregon coastal province and the Willamette basin. Title: Monitoring design for riparian forests in the Pacific Northwest : research plan Author: Bollman, Mike, National Health and Environmental Effects Laboratory., Oregon State University, Stepp, Jennifer, United States. Environmental Protection Agency. ǂb Office of Research and Development, United States. Forest Service, Barker, Jerry R., Bradshaw, Gay, Ringold, Paul L., Cline, Steven Paul, Carson, Ward, Dynamac Corporation, Fiorella, Maria R. The goal of this project is to recommend a broadly-acceptale efficient and effective methodology for characterizing streamside riparian attributes in forested settings at the site grain for regional monitoring. The authors consider monitoring design in the context of three interacting constraints: ecological functions, capabilities of technologies, and user needs. The focus is on fine grained remote methods. Comparison between candidate selected monitoring systems provides for an initial formulation of a monitoring design. A series of evaluations of these initial formulations provides for an initial recommendation. With the state's interest in the status of coastal fishes, and the programmatic interest of EPA's Western Ecology Division, the areas selected for study are in the Oregon coastal province and the Willamette basin. Close

• 42. [Article] The Impact of Disturbance on Carbon Stores and Dynamics in Forests of Coastal Alaska

  Changes in climate caused by increased concentrations of carbon dioxide (CO₂) in the Earth’s atmosphere have led land and ocean surface temperatures to increase by 0.85°C and sea level to increase by 19 ...

  Citation × Citation Citation Abstract Copy Title: The Impact of Disturbance on Carbon Stores and Dynamics in Forests of Coastal Alaska Author: Yatskov, Mikhail A. Changes in climate caused by increased concentrations of carbon dioxide (CO₂) in the Earth’s atmosphere have led land and ocean surface temperatures to increase by 0.85°C and sea level to increase by 19 cm relative to preindustrial times. Global climate change will lead to further alterations in mean temperature and precipitation, as well as their extremes that are likely to influence disturbance regimes. Disturbance play an important role in forest dynamics and succession, by influencing forest ecosystems structure and function, reorganizing forests by reducing live and increasing dead matter, and thus affecting ecosystem carbon (C) balances. Under a changing climate disturbances are likely to cause widespread tree mortality across forested landscapes, creating vast amounts of coarse woody debris (CWD) that will emit C to the atmosphere to a degree that regional C balances and future C dynamics are likely to change. C balance of forested regions depends on inputs in form of C sequestered by live components during growth and outputs in form of C emitted from dead components through decomposition and combustion. Live trees in many forest ecosystems represent the largest aboveground C pool and the dynamics of this pool, as controlled by growth and mortality, have been extensively studied. In contrast, few have examined either the post-disturbance fate of CWD C or assessed C storage potential of salvaged biomass despite the occurrence of multiple recent large-scale disturbance events. Biomass and C stores and their uncertainty were estimated in the Temperate and the Boreal ecoregions of Coastal Alaska using the empirical data from the Forest Inventory and Analysis (FIA) program, literature data, and modeling using standard methods employed by the FIA program. The average aboveground woody live (218.9±4.6 Mg/ha) and log (28.1±1.8 Mg/ha) biomass in the Temperate ecoregion were among the lowest in the Pacific Northwest, whereas snag biomass (30.5±1.0 Mg/ha) was among the highest. In the Boreal ecoregion, CWD biomass comprised almost 50% of the regional aboveground woody store (76.7±3.8 Mg/ha) with bark beetle damaged stands containing 82% of the total CWD biomass. In contrast, in the Temperate ecoregion, CWD comprised 20% of the regional aboveground woody store (277.5 ±5.4 Mg/ha) with 76% of total CWD biomass in undisturbed stands. Total C stores estimates in Coastal Alaska ranged between 1523.6 and 1892.8 Tg with the highest contribution from soils and the largest potential reductions in uncertainty related to the tree and soils C pools. The impact of a large-scale spruce bark beetle (SBB) outbreak on aboveground dead wood C dynamics on the Kenai Peninsula was modeled utilizing data from the FIA program and CWD decomposition rate-constants from a chronosequence and decomposition-vectors analysis. Decomposition rate-constants from the chronosequence ranged between -0.015 yr⁻¹ and -0.022 yr⁻¹ for logs and -0.003 yr⁻¹ and +0.002 yr⁻¹ for snags. Decomposition rate-constants from the decomposition-vectors ranged between -0.045 yr⁻¹ and +0.003 yr⁻¹ among decomposition phases and -0.048 yr⁻¹ and +0.006 yr⁻¹ among decay classes. Relative to log generating disturbances those creating snags delayed C flux from CWD to the atmosphere, produced a smaller magnitude C flux, and had the potential to store 10% to 66% more C in a disturbed system over time. The effect of several management strategies ranging from "leave-as-is" to "salvage-and-utilization" on C stores and emissions following SBB outbreak on Kenai Peninsula, Alaska was evaluated. A forest with immediate post-disturbance regeneration reached pre-disturbance C stores faster than one with delayed regeneration. Lack of regeneration, representing a loss of tree cover on the disturbed portion of the landscape, caused a permanent decrease in wood C stores. Among the "salvage-and-utilization" scenarios considered, biomass fuel production with substitution for fossil fuels created the largest long-term C storage assuming the substitution was permanent. Given that reduction in near-term emissions may be a more robust strategy than long-term ones, the "leave-as-is" scenarios may represent the most feasible way to mitigate global climate change following disturbance. Title: The Impact of Disturbance on Carbon Stores and Dynamics in Forests of Coastal Alaska Author: Yatskov, Mikhail A. Changes in climate caused by increased concentrations of carbon dioxide (CO₂) in the Earth’s atmosphere have led land and ocean surface temperatures to increase by 0.85°C and sea level to increase by 19 cm relative to preindustrial times. Global climate change will lead to further alterations in mean temperature and precipitation, as well as their extremes that are likely to influence disturbance regimes. Disturbance play an important role in forest dynamics and succession, by influencing forest ecosystems structure and function, reorganizing forests by reducing live and increasing dead matter, and thus affecting ecosystem carbon (C) balances. Under a changing climate disturbances are likely to cause widespread tree mortality across forested landscapes, creating vast amounts of coarse woody debris (CWD) that will emit C to the atmosphere to a degree that regional C balances and future C dynamics are likely to change. C balance of forested regions depends on inputs in form of C sequestered by live components during growth and outputs in form of C emitted from dead components through decomposition and combustion. Live trees in many forest ecosystems represent the largest aboveground C pool and the dynamics of this pool, as controlled by growth and mortality, have been extensively studied. In contrast, few have examined either the post-disturbance fate of CWD C or assessed C storage potential of salvaged biomass despite the occurrence of multiple recent large-scale disturbance events. Biomass and C stores and their uncertainty were estimated in the Temperate and the Boreal ecoregions of Coastal Alaska using the empirical data from the Forest Inventory and Analysis (FIA) program, literature data, and modeling using standard methods employed by the FIA program. The average aboveground woody live (218.9±4.6 Mg/ha) and log (28.1±1.8 Mg/ha) biomass in the Temperate ecoregion were among the lowest in the Pacific Northwest, whereas snag biomass (30.5±1.0 Mg/ha) was among the highest. In the Boreal ecoregion, CWD biomass comprised almost 50% of the regional aboveground woody store (76.7±3.8 Mg/ha) with bark beetle damaged stands containing 82% of the total CWD biomass. In contrast, in the Temperate ecoregion, CWD comprised 20% of the regional aboveground woody store (277.5 ±5.4 Mg/ha) with 76% of total CWD biomass in undisturbed stands. Total C stores estimates in Coastal Alaska ranged between 1523.6 and 1892.8 Tg with the highest contribution from soils and the largest potential reductions in uncertainty related to the tree and soils C pools. The impact of a large-scale spruce bark beetle (SBB) outbreak on aboveground dead wood C dynamics on the Kenai Peninsula was modeled utilizing data from the FIA program and CWD decomposition rate-constants from a chronosequence and decomposition-vectors analysis. Decomposition rate-constants from the chronosequence ranged between -0.015 yr⁻¹ and -0.022 yr⁻¹ for logs and -0.003 yr⁻¹ and +0.002 yr⁻¹ for snags. Decomposition rate-constants from the decomposition-vectors ranged between -0.045 yr⁻¹ and +0.003 yr⁻¹ among decomposition phases and -0.048 yr⁻¹ and +0.006 yr⁻¹ among decay classes. Relative to log generating disturbances those creating snags delayed C flux from CWD to the atmosphere, produced a smaller magnitude C flux, and had the potential to store 10% to 66% more C in a disturbed system over time. The effect of several management strategies ranging from "leave-as-is" to "salvage-and-utilization" on C stores and emissions following SBB outbreak on Kenai Peninsula, Alaska was evaluated. A forest with immediate post-disturbance regeneration reached pre-disturbance C stores faster than one with delayed regeneration. Lack of regeneration, representing a loss of tree cover on the disturbed portion of the landscape, caused a permanent decrease in wood C stores. Among the "salvage-and-utilization" scenarios considered, biomass fuel production with substitution for fossil fuels created the largest long-term C storage assuming the substitution was permanent. Given that reduction in near-term emissions may be a more robust strategy than long-term ones, the "leave-as-is" scenarios may represent the most feasible way to mitigate global climate change following disturbance. Close

• 43. [Article] Linking Ecology and Economics for Ecosystem Management

  This article outlines an approach, based on ecosystem services, for assessing the trade-offs inherent in managing humans embedded in ecological systems. Evaluating these trade-offs requires an understanding ...

  Citation × Citation Citation Abstract Copy Title: Linking Ecology and Economics for Ecosystem Management Author: Farber, Stephen, Costanza, Robert, Childers, Daniel L., Erickson, Jon, Gross, Katherine, Grove, Morgan, Hopkinson, Charles S., Kahn, James, Pincetl, Stephanie, Troy, Austin, Warren, Paige, Wilson, Matthew Year: 2006 This article outlines an approach, based on ecosystem services, for assessing the trade-offs inherent in managing humans embedded in ecological systems. Evaluating these trade-offs requires an understanding of the biophysical magnitudes of the changes in ecosystem services that result from human actions, and of the impact of these changes on human welfare.We summarize the state of the art of ecosystem services?based management and the information needs for applying it. Three case studies of Long Term Ecological Research (LTER) sites?coastal, urban, and agricultural? illustrate the usefulness, information needs, quantification possibilities, and methods for this approach. One example of the application of this approach, with rigorously established service changes and valuations taken from the literature, is used to illustrate the potential for full economic valuation of several agricultural landscape management options, including managing for water quality, biodiversity, and crop productivity. Title: Linking Ecology and Economics for Ecosystem Management Author: Farber, Stephen, Costanza, Robert, Childers, Daniel L., Erickson, Jon, Gross, Katherine, Grove, Morgan, Hopkinson, Charles S., Kahn, James, Pincetl, Stephanie, Troy, Austin, Warren, Paige, Wilson, Matthew Year: 2006 This article outlines an approach, based on ecosystem services, for assessing the trade-offs inherent in managing humans embedded in ecological systems. Evaluating these trade-offs requires an understanding of the biophysical magnitudes of the changes in ecosystem services that result from human actions, and of the impact of these changes on human welfare.We summarize the state of the art of ecosystem services?based management and the information needs for applying it. Three case studies of Long Term Ecological Research (LTER) sites?coastal, urban, and agricultural? illustrate the usefulness, information needs, quantification possibilities, and methods for this approach. One example of the application of this approach, with rigorously established service changes and valuations taken from the literature, is used to illustrate the potential for full economic valuation of several agricultural landscape management options, including managing for water quality, biodiversity, and crop productivity. Close

• 44. [Article] Oregon Natural Areas Plan

  The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, ...

  Citation × Citation Citation Abstract Copy Title: Oregon Natural Areas Plan Author: Oregon Natural Heritage Advisory Council Year: 2010 The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, deserts, marshes, estuaries, dunes, rocky headlands, lakes and streams. There are a number of reasons it is so diverse. First are the extremes of climate, with rainfall ranging from over 200 inches a year along Oregon’s north coast, to less than 7 inches a year in the Alvord Desert, and temperatures from the very mild banana belt along the coast near the California border to the extremes of the high alpine areas of the Wallowa Mountains. Secondly, Oregon is diverse geographically and geologically, having ancient serpentine landscapes in the Siskiyou Mountains and recent volcanics in the Cascades and the deepest gorge in North America at Hells Canyon. Lastly, Oregon is a floristic crossroads, with arctic boreal species finding their southern limit, Rocky Mountain species common in northeastern Oregon, Great Basin species in southeastern Oregon, and California coastal and Sierra species in the southwest, all mixing with native northwestern taxa to create a wide array of habitats. Title: Oregon Natural Areas Plan Author: Oregon Natural Heritage Advisory Council Year: 2010 The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, deserts, marshes, estuaries, dunes, rocky headlands, lakes and streams. There are a number of reasons it is so diverse. First are the extremes of climate, with rainfall ranging from over 200 inches a year along Oregon’s north coast, to less than 7 inches a year in the Alvord Desert, and temperatures from the very mild banana belt along the coast near the California border to the extremes of the high alpine areas of the Wallowa Mountains. Secondly, Oregon is diverse geographically and geologically, having ancient serpentine landscapes in the Siskiyou Mountains and recent volcanics in the Cascades and the deepest gorge in North America at Hells Canyon. Lastly, Oregon is a floristic crossroads, with arctic boreal species finding their southern limit, Rocky Mountain species common in northeastern Oregon, Great Basin species in southeastern Oregon, and California coastal and Sierra species in the southwest, all mixing with native northwestern taxa to create a wide array of habitats. Close

• 45. [Article] A Morphologic Proxy for Debris Flow Erosion With Application to the Earthquake Deformation Cycle, Cascadia Subduction Zone, USA

  In unglaciated steeplands, valley reaches dominated by debris flow scour and incision set landscape form as they often account for > 80% of valley network length and relief. While hillslope and fluvial ...

  Citation × Citation Citation Abstract Copy Title: A Morphologic Proxy for Debris Flow Erosion With Application to the Earthquake Deformation Cycle, Cascadia Subduction Zone, USA Author: Penserini, Brian D., Roering, Joshua J., Strieg, Ashley Year: 2017 In unglaciated steeplands, valley reaches dominated by debris flow scour and incision set landscape form as they often account for > 80% of valley network length and relief. While hillslope and fluvial process models have frequently been combined with digital topography to develop morphologic proxies for erosion rate and drainage divide migration, debris-flow-dominated networks, despite their ubiquity, have not been exploited for this purpose. Here, we applied an empirical function that describes how slope-area data systematically deviate from so-called fluvial power-law behavior at small drainage areas. Using airborne LiDAR data for 83 small (~ 1 km2) catchments in the western Oregon Coast Range, we quantified variation in model parameters and observed that the curvature of the power-law scaling deviation varies with catchment-averaged erosion rate estimated from cosmogenic nuclides in stream sediments. Given consistent climate and lithology across our study area and assuming steady erosion, we used this calibrated denudation-morphology relationship to map spatial patterns of long-term uplift for our study catchments. By combining our predicted pattern of long-term uplift rate with paleoseismic and geodetic (tide gauge, GPS, and leveling) data, we estimated the spatial distribution of coseismic subsidence experienced during megathrust earthquakes along the Cascadia Subduction Zone. Our estimates of coseismic subsidence near the coast (0.4 to 0.7 m for earthquake recurrence intervals of 300 to 500 years) agree with field measurements from numerous stratigraphic studies. Our results also demonstrate that coseismic subsidence decreases inland to negligible values > 25 km from the coast, reflecting the diminishing influence of the earthquake deformation cycle on vertical changes of the interior coastal ranges. More generally, our results demonstrate that debris flow valley networks serve as highly localized, yet broadly distributed indicators of erosion (and rock uplift), making them invaluable for mapping crustal deformation and landscape adjustment. © 2017 Elsevier B.V. Title: A Morphologic Proxy for Debris Flow Erosion With Application to the Earthquake Deformation Cycle, Cascadia Subduction Zone, USA Author: Penserini, Brian D., Roering, Joshua J., Strieg, Ashley Year: 2017 In unglaciated steeplands, valley reaches dominated by debris flow scour and incision set landscape form as they often account for > 80% of valley network length and relief. While hillslope and fluvial process models have frequently been combined with digital topography to develop morphologic proxies for erosion rate and drainage divide migration, debris-flow-dominated networks, despite their ubiquity, have not been exploited for this purpose. Here, we applied an empirical function that describes how slope-area data systematically deviate from so-called fluvial power-law behavior at small drainage areas. Using airborne LiDAR data for 83 small (~ 1 km2) catchments in the western Oregon Coast Range, we quantified variation in model parameters and observed that the curvature of the power-law scaling deviation varies with catchment-averaged erosion rate estimated from cosmogenic nuclides in stream sediments. Given consistent climate and lithology across our study area and assuming steady erosion, we used this calibrated denudation-morphology relationship to map spatial patterns of long-term uplift for our study catchments. By combining our predicted pattern of long-term uplift rate with paleoseismic and geodetic (tide gauge, GPS, and leveling) data, we estimated the spatial distribution of coseismic subsidence experienced during megathrust earthquakes along the Cascadia Subduction Zone. Our estimates of coseismic subsidence near the coast (0.4 to 0.7 m for earthquake recurrence intervals of 300 to 500 years) agree with field measurements from numerous stratigraphic studies. Our results also demonstrate that coseismic subsidence decreases inland to negligible values > 25 km from the coast, reflecting the diminishing influence of the earthquake deformation cycle on vertical changes of the interior coastal ranges. More generally, our results demonstrate that debris flow valley networks serve as highly localized, yet broadly distributed indicators of erosion (and rock uplift), making them invaluable for mapping crustal deformation and landscape adjustment. © 2017 Elsevier B.V. Close

• 46. [Article] Impacts of Permafrost Degradation on a Stream in Taylor Valley, Antarctica

  The McMurdo Dry Valleys (MDV) of Antarctica are an ice-free landscape that supports a complex, microbially dominated ecosystem despite a severely arid, cold environment (< 5 cm water equivalent/y, − 18 ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Permafrost Degradation on a Stream in Taylor Valley, Antarctica Author: Sudman, Zachary, Gooseff, Michael N., Fountain, Andrew G., Levy, Joseph S. Year: 2017 The McMurdo Dry Valleys (MDV) of Antarctica are an ice-free landscape that supports a complex, microbially dominated ecosystem despite a severely arid, cold environment (< 5 cm water equivalent/y, − 18 °C mean annual air temperature). Recent observations of permafrost degradation in the coastal zones of the MDV suggest that this region is nearing a threshold of rapid landscape change. In 2012, substantial thermokarst development was observed along several kilometers of the west branch of Crescent Stream in Taylor Valley mostly in the form of bank failures, whereas the adjacent east branch was unaffected. The objective of this study was to quantify the changes to the stream banks of the west branch of Crescent Stream and to determine the impacts on the composition of the stream bed material. Three annually repeated terrestrial LiDAR scans were compared to determine the rates of ground surface change caused by thermokarst formation on the stream bank. The areal extent of the thermokarst was shown to be decreasing; however, the average vertical rate of retreat remained constant. Field measurements of bed materials indicated that the west branch and the reach downstream of the confluence (of east and west branches) consistently contained more fines than the unaffected east branch. This suggests that the finer bed material is a result of the thermokarst development on the west branch. These finer bed material compositions are likely to increase the mobility of the bed material, which will have implications for stream morphology, stream algal mat communities, and downstream aquatic ecosystems. Title: Impacts of Permafrost Degradation on a Stream in Taylor Valley, Antarctica Author: Sudman, Zachary, Gooseff, Michael N., Fountain, Andrew G., Levy, Joseph S. Year: 2017 The McMurdo Dry Valleys (MDV) of Antarctica are an ice-free landscape that supports a complex, microbially dominated ecosystem despite a severely arid, cold environment (< 5 cm water equivalent/y, − 18 °C mean annual air temperature). Recent observations of permafrost degradation in the coastal zones of the MDV suggest that this region is nearing a threshold of rapid landscape change. In 2012, substantial thermokarst development was observed along several kilometers of the west branch of Crescent Stream in Taylor Valley mostly in the form of bank failures, whereas the adjacent east branch was unaffected. The objective of this study was to quantify the changes to the stream banks of the west branch of Crescent Stream and to determine the impacts on the composition of the stream bed material. Three annually repeated terrestrial LiDAR scans were compared to determine the rates of ground surface change caused by thermokarst formation on the stream bank. The areal extent of the thermokarst was shown to be decreasing; however, the average vertical rate of retreat remained constant. Field measurements of bed materials indicated that the west branch and the reach downstream of the confluence (of east and west branches) consistently contained more fines than the unaffected east branch. This suggests that the finer bed material is a result of the thermokarst development on the west branch. These finer bed material compositions are likely to increase the mobility of the bed material, which will have implications for stream morphology, stream algal mat communities, and downstream aquatic ecosystems. Close

• 47. [Article] Relationships among juvenile anadromous salmonids, their freshwater habitat, and landscape characteristics over multiple years and spatial scales in the Elk River, Oregon

  Research on the distribution of juvenile salmonids in streams has been dominated by studies examining small areas over short periods. However, information relevant to freshwater influences on population ...

  Citation × Citation Citation Abstract Copy Title: Relationships among juvenile anadromous salmonids, their freshwater habitat, and landscape characteristics over multiple years and spatial scales in the Elk River, Oregon Author: Burnett, Kelly M. Research on the distribution of juvenile salmonids in streams has been dominated by studies examining small areas over short periods. However, information relevant to freshwater influences on population persistence is likely to derive from longer-term, multi-scale studies. Relationships were examined among juvenile anadromous salmonids, their freshwater habitat, and landscape characteristics throughout the Elk River, Oregon over 7 years at multiple spatial scales. Ocean-type chinook salmon (Oncorhynchus tshawytscha), coho salmon (0. kisutch), coastal cutthroat trout (0. clarki) and winter-run steelhead (0. mykiss) comprised the salmonid assemblage. Habitat selection was quantified at stream system, valley segment, and channel unit scales by selection ratios estimated with bootstrapping methods. Unconstrained valleys in tributaries and pools in the mainstem were typically selected by each species except steelhead, which often avoided these. Valley segment types generally did not differ for characteristics routinely assessed in stream surveys. Thus, fish probably perceived other biotic or abiotic differences among valley segment types. Evidence suggested competition may have influenced selection by coho and chinook salmon. Discriminant analysis indicated that level of use by juvenile chinook salmon appeared related to valley segment type and spatial position. Unconstrained valleys, nearby valley segments, and valley segments with larger, deeper pools, containing more wood were most highly used by chinook salmon. Mean volume and maximum depth of pools were each directly related to catchment area, which explained more variation than landscape characteristics summarized at any of five spatial scales. At each scale except the most spatially extensive, wood density in valley segments was negatively related to the percent area in resistant rock types and positively related to the percent area in mature to old forests. The most variation was explained with these landscape variables summarized at an intermediate spatial scale (i.e., sub-catchment). Although spatial scales appeared similar in processes affecting wood density, finer scales omitted key source areas for wood delivery, and coarser scales included source areas less tightly coupled to wood dynamics in surveyed channels. If only 1 or 2 years of data or one spatial scale had been examined, as commonly occurs, conclusions may have differed substantially from those in this study. Title: Relationships among juvenile anadromous salmonids, their freshwater habitat, and landscape characteristics over multiple years and spatial scales in the Elk River, Oregon Author: Burnett, Kelly M. Research on the distribution of juvenile salmonids in streams has been dominated by studies examining small areas over short periods. However, information relevant to freshwater influences on population persistence is likely to derive from longer-term, multi-scale studies. Relationships were examined among juvenile anadromous salmonids, their freshwater habitat, and landscape characteristics throughout the Elk River, Oregon over 7 years at multiple spatial scales. Ocean-type chinook salmon (Oncorhynchus tshawytscha), coho salmon (0. kisutch), coastal cutthroat trout (0. clarki) and winter-run steelhead (0. mykiss) comprised the salmonid assemblage. Habitat selection was quantified at stream system, valley segment, and channel unit scales by selection ratios estimated with bootstrapping methods. Unconstrained valleys in tributaries and pools in the mainstem were typically selected by each species except steelhead, which often avoided these. Valley segment types generally did not differ for characteristics routinely assessed in stream surveys. Thus, fish probably perceived other biotic or abiotic differences among valley segment types. Evidence suggested competition may have influenced selection by coho and chinook salmon. Discriminant analysis indicated that level of use by juvenile chinook salmon appeared related to valley segment type and spatial position. Unconstrained valleys, nearby valley segments, and valley segments with larger, deeper pools, containing more wood were most highly used by chinook salmon. Mean volume and maximum depth of pools were each directly related to catchment area, which explained more variation than landscape characteristics summarized at any of five spatial scales. At each scale except the most spatially extensive, wood density in valley segments was negatively related to the percent area in resistant rock types and positively related to the percent area in mature to old forests. The most variation was explained with these landscape variables summarized at an intermediate spatial scale (i.e., sub-catchment). Although spatial scales appeared similar in processes affecting wood density, finer scales omitted key source areas for wood delivery, and coarser scales included source areas less tightly coupled to wood dynamics in surveyed channels. If only 1 or 2 years of data or one spatial scale had been examined, as commonly occurs, conclusions may have differed substantially from those in this study. Close

• 48. [Article] Simulated response of ecosystem processes to climate change in northern California and western Nevada

  In order to investigate potential climate impacts on landscape-scale ecosystem processes, I implemented a dynamic general vegetation model (DGVM) over a large domain in northern California and western ...

  Citation × Citation Citation Abstract Copy Title: Simulated response of ecosystem processes to climate change in northern California and western Nevada Author: McGlinchy, Maureen C. In order to investigate potential climate impacts on landscape-scale ecosystem processes, I implemented a dynamic general vegetation model (DGVM) over a large domain in northern California and western Nevada on a rectangular grid of ca. 800-meter spatial resolution. I used 100 years of observed, monthly climate and nine future climate projections in an attempt to explore the range of possible climate futures in the region. I selected three general circulation models (MIROC3.2(medres), UKMO-HadCM3 and CSIRO-Mk3.0), incorporating a range of 2xCO₂ temperature sensitivity. Each GCM was run through three carbon dioxide emissions scenarios (SRES A2, A1B and B1). For this analysis, I focused the study on the simulated ecological impacts under the three A2 scenarios. Historical observations and future climate scenarios were interpolated to the 800-meter grid by the PRISM model. MC1, a systems-based DGVM, compared favorably to observed data for simulations of vegetation distribution and annual streamflow. MC1 slightly overestimated annual production in the Sierra Nevada and Klamath Mountains and underestimated it in the Coast Range and Eastern Cascades. MC1 displayed a low bias for annual area burned and high bias for pyrogenic emissions. Validation of simulated model output was complicated because MC1 does not consider the effects of land management on ecosystems and the study region is heavily-impacted by development, logging, fire suppression, grazing and pre-European, indigenous land-use and burning. Under all future climate projections, an increase in growing season length and temperature led to the replacement of tundra and subalpine vegetation types with temperate conifer forest. Increased winter minimum temperatures promoted the expansion of mixed needleleaf-broadleaf forest, particularly in the mid-elevations of the Sierra Nevada and in coastal forests. In the MIROC3.2 and HadCM3 scenarios, ecosystem-level net primary productivity (NPP) did not increase with enhanced CO₂ fertilization because production remained limited by water, even though both NPP and water-use-efficiency were increased at the leaf level in proportion to CO₂ concentration. Increases in NPP were projected in CSIRO-Mk3, but increased precipitation and warmer temperatures also increased rates of heterotrophic respiration for no net gain in net ecosystem productivity (NEP). Fire extent and severity increased in all scenarios, mostly driven by significant decreases in mountainous snowpack and earlier snowmelt. Thus, a relatively constant NEP and increased fire emissions produced decreases in total ecosystem carbon across all future scenarios. Projected annual streamflow varied between future climate scenarios and was highly influenced by projected precipitation. In all future simulations, high-elevation mountainous landscapes were highly sensitive to projected changes in climate, largely attributable to an increased growing season and temperature, decreased snowpack and reduced fire return interval. Coastal forests were also highly susceptible to changes in vegetation type and increases in fire. Several sources contribute to uncertainty in MC1, including input datasets, model assumptions, uncertainties in ecosystem science, and questions of scale. Therefore, these results should be considered preliminary, but useful in suggesting a range of plausible ecological futures as we continue to refine model capabilities. Title: Simulated response of ecosystem processes to climate change in northern California and western Nevada Author: McGlinchy, Maureen C. In order to investigate potential climate impacts on landscape-scale ecosystem processes, I implemented a dynamic general vegetation model (DGVM) over a large domain in northern California and western Nevada on a rectangular grid of ca. 800-meter spatial resolution. I used 100 years of observed, monthly climate and nine future climate projections in an attempt to explore the range of possible climate futures in the region. I selected three general circulation models (MIROC3.2(medres), UKMO-HadCM3 and CSIRO-Mk3.0), incorporating a range of 2xCO₂ temperature sensitivity. Each GCM was run through three carbon dioxide emissions scenarios (SRES A2, A1B and B1). For this analysis, I focused the study on the simulated ecological impacts under the three A2 scenarios. Historical observations and future climate scenarios were interpolated to the 800-meter grid by the PRISM model. MC1, a systems-based DGVM, compared favorably to observed data for simulations of vegetation distribution and annual streamflow. MC1 slightly overestimated annual production in the Sierra Nevada and Klamath Mountains and underestimated it in the Coast Range and Eastern Cascades. MC1 displayed a low bias for annual area burned and high bias for pyrogenic emissions. Validation of simulated model output was complicated because MC1 does not consider the effects of land management on ecosystems and the study region is heavily-impacted by development, logging, fire suppression, grazing and pre-European, indigenous land-use and burning. Under all future climate projections, an increase in growing season length and temperature led to the replacement of tundra and subalpine vegetation types with temperate conifer forest. Increased winter minimum temperatures promoted the expansion of mixed needleleaf-broadleaf forest, particularly in the mid-elevations of the Sierra Nevada and in coastal forests. In the MIROC3.2 and HadCM3 scenarios, ecosystem-level net primary productivity (NPP) did not increase with enhanced CO₂ fertilization because production remained limited by water, even though both NPP and water-use-efficiency were increased at the leaf level in proportion to CO₂ concentration. Increases in NPP were projected in CSIRO-Mk3, but increased precipitation and warmer temperatures also increased rates of heterotrophic respiration for no net gain in net ecosystem productivity (NEP). Fire extent and severity increased in all scenarios, mostly driven by significant decreases in mountainous snowpack and earlier snowmelt. Thus, a relatively constant NEP and increased fire emissions produced decreases in total ecosystem carbon across all future scenarios. Projected annual streamflow varied between future climate scenarios and was highly influenced by projected precipitation. In all future simulations, high-elevation mountainous landscapes were highly sensitive to projected changes in climate, largely attributable to an increased growing season and temperature, decreased snowpack and reduced fire return interval. Coastal forests were also highly susceptible to changes in vegetation type and increases in fire. Several sources contribute to uncertainty in MC1, including input datasets, model assumptions, uncertainties in ecosystem science, and questions of scale. Therefore, these results should be considered preliminary, but useful in suggesting a range of plausible ecological futures as we continue to refine model capabilities. Close

• 49. [Article] Where's the ground surface? Elevation bias in LIDAR-derived digital elevation models due to dense vegetation in Oregon tidal marshes

  Light Detection and Ranging (LIDAR) is a powerful resource for coastal and wetland managers and its use is increasing. Vegetation density and other land cover characteristics influence the accuracy of ...

  Citation × Citation Citation Abstract Copy Title: Where's the ground surface? Elevation bias in LIDAR-derived digital elevation models due to dense vegetation in Oregon tidal marshes Author: Ewald, Michael J. Light Detection and Ranging (LIDAR) is a powerful resource for coastal and wetland managers and its use is increasing. Vegetation density and other land cover characteristics influence the accuracy of LIDAR-derived ground surface digital elevation models; however, the degree to which wetland land cover biases LIDAR estimates of the ground surface is largely unknown. The minimum-bin LIDAR gridding technique has been proposed as a way to mitigate dense vegetation interference to generate LIDAR-derived digital elevation models (DEM). Past research has focused on the ability to resolve the marsh plain elevation and only limited research has investigated the overall DEM accuracy across the landscape using a wide range of cell sizes and land cover classes. I compared LIDAR-derived DEM accuracy across a 174 ha tidal wetland restoration site with a mix of native wetland and non-native agricultural pasture species. I found an optimum cell size of 1.4 m (1.96 m²) with a mean positive bias of 4.5 cm and a mean absolute error of 24.3 cm. At cell sizes smaller than the optimum, vegetation interferes with the LIDAR sensor and positively biases DEM models. At cell sizes larger than 1.4 m, the DEM captures and favors low features within the landscape, such as channels and ditches, which thereby degrade overall DEM performance. In addition, I investigated LIDAR interference by twelve common tidal wetland vegetation associations across six Oregon estuaries, using survey-grade Global Positioning System (GPS) measurements of the wetland surface and quantitative vegetation data (percent cover by species) for each measurement location. The fundamental vertical accuracy (FVA) of the LIDAR datasets was 4.5 cm root mean square error (RMSE) and had no consistent positive or negative bias in open landcover. Within wetland vegetation communities, my results suggest that LIDAR estimates of the ground surface in tidal wetlands are typically 10 cm to 30 cm above GPS measurements. Plant associations dominated by Carex obnupta and Carex lyngbyei exhibited the largest discrepancy between LIDAR and GPS measurements (mean discrepancies 36.6 cm and 48.8 cm respectively). The smallest errors observed in the study were about 10 cm to 11 cm and occurred in several different plant associations, including two low tidal marsh associations dominated by a mixture of Deschampsia cespitosa, Distichlis spicata, Sarcocornia perennis and Jaumea carnosa. These results suggest that the minimum-bin gridding technique for LIDAR may mitigate vegetation interference by densely vegetated land covers within LIDAR-derived DEM. However, care should be taken to select an appropriate cell size and validate the results before relying on the DEM for analysis. My research yields new information for coastal LIDAR users and increases our understanding of uncertainty in LIDAR-derived datasets to improve the ability to accurately evaluate and manage coastal environments. Title: Where's the ground surface? Elevation bias in LIDAR-derived digital elevation models due to dense vegetation in Oregon tidal marshes Author: Ewald, Michael J. Light Detection and Ranging (LIDAR) is a powerful resource for coastal and wetland managers and its use is increasing. Vegetation density and other land cover characteristics influence the accuracy of LIDAR-derived ground surface digital elevation models; however, the degree to which wetland land cover biases LIDAR estimates of the ground surface is largely unknown. The minimum-bin LIDAR gridding technique has been proposed as a way to mitigate dense vegetation interference to generate LIDAR-derived digital elevation models (DEM). Past research has focused on the ability to resolve the marsh plain elevation and only limited research has investigated the overall DEM accuracy across the landscape using a wide range of cell sizes and land cover classes. I compared LIDAR-derived DEM accuracy across a 174 ha tidal wetland restoration site with a mix of native wetland and non-native agricultural pasture species. I found an optimum cell size of 1.4 m (1.96 m²) with a mean positive bias of 4.5 cm and a mean absolute error of 24.3 cm. At cell sizes smaller than the optimum, vegetation interferes with the LIDAR sensor and positively biases DEM models. At cell sizes larger than 1.4 m, the DEM captures and favors low features within the landscape, such as channels and ditches, which thereby degrade overall DEM performance. In addition, I investigated LIDAR interference by twelve common tidal wetland vegetation associations across six Oregon estuaries, using survey-grade Global Positioning System (GPS) measurements of the wetland surface and quantitative vegetation data (percent cover by species) for each measurement location. The fundamental vertical accuracy (FVA) of the LIDAR datasets was 4.5 cm root mean square error (RMSE) and had no consistent positive or negative bias in open landcover. Within wetland vegetation communities, my results suggest that LIDAR estimates of the ground surface in tidal wetlands are typically 10 cm to 30 cm above GPS measurements. Plant associations dominated by Carex obnupta and Carex lyngbyei exhibited the largest discrepancy between LIDAR and GPS measurements (mean discrepancies 36.6 cm and 48.8 cm respectively). The smallest errors observed in the study were about 10 cm to 11 cm and occurred in several different plant associations, including two low tidal marsh associations dominated by a mixture of Deschampsia cespitosa, Distichlis spicata, Sarcocornia perennis and Jaumea carnosa. These results suggest that the minimum-bin gridding technique for LIDAR may mitigate vegetation interference by densely vegetated land covers within LIDAR-derived DEM. However, care should be taken to select an appropriate cell size and validate the results before relying on the DEM for analysis. My research yields new information for coastal LIDAR users and increases our understanding of uncertainty in LIDAR-derived datasets to improve the ability to accurately evaluate and manage coastal environments. Close

• 50. [Article] Neacoxie Watershed

  Abstract -- Previously, little information was known about the ecology or the condition of native habitats in the Neacoxie sub-watershed that drains from the city of Warrenton into the north section of ...

  Citation × Citation Citation Abstract Copy Title: Neacoxie Watershed Abstract -- Previously, little information was known about the ecology or the condition of native habitats in the Neacoxie sub-watershed that drains from the city of Warrenton into the north section of the Necanicum Estuary in the city of Seaside. In 2002, the Necanicum Watershed Council completed an assessment for the Necanicum River watershed, but with major knowledge gaps for the Neacoxie watershed, which includes the Neacoxie Creek corridor and the Clatsop Plains. In order for the North Coast Land Conservancy (NCLC) and other land managers to develop stewardship priorities and to make informed decisions about land management actions in this region, additional information was required. Together with the Necanicum Watershed Council and the North Coast Watershed Association, NCLC secured funding to conduct habitat inventories of the Neacoxie watershed. The Neacoxie Watershed Assessment summarizes the results of terrestrial plant transects and aquatic plant surveys completed in the summer of 2011 on ten properties owned by the North Coast Land Conservancy (NCLC) in the Neacoxie Creek watershed (please refer to Appendices A & B). Habitat types include stabilized sand dunes dominated by coastal prairie habitat, interdunal wetland swales and lakes, upland Sitka spruce forest, and forested wetlands. Percent composition of each plant community type observed was calculated. Invasive non-native plant species were recorded. Surveys were also conducted for both native and non-native plants in four water bodies owned by NCLC or adjacent to land trust properties. The plant community data that were collected will be used to evaluate baseline ecological conditions in the Neacoxie watershed. Plant communities can be used as indicators of long-term tidal and hydrologic conditions as well as the ecological health of the landscape. Repeated measurements can be used to assess community changes over time and to assess how plant community composition compares to that described for natural conditions. This information will assist the land trust in making science-based stewardship decisions on its properties, and can be used by other landowners to better understand changes occurring in plant communities in similar habitats on their properties as a result of human disturbance (e.g., land development, farming, grazing) and invasion by non-native plants. Title: Neacoxie Watershed Abstract -- Previously, little information was known about the ecology or the condition of native habitats in the Neacoxie sub-watershed that drains from the city of Warrenton into the north section of the Necanicum Estuary in the city of Seaside. In 2002, the Necanicum Watershed Council completed an assessment for the Necanicum River watershed, but with major knowledge gaps for the Neacoxie watershed, which includes the Neacoxie Creek corridor and the Clatsop Plains. In order for the North Coast Land Conservancy (NCLC) and other land managers to develop stewardship priorities and to make informed decisions about land management actions in this region, additional information was required. Together with the Necanicum Watershed Council and the North Coast Watershed Association, NCLC secured funding to conduct habitat inventories of the Neacoxie watershed. The Neacoxie Watershed Assessment summarizes the results of terrestrial plant transects and aquatic plant surveys completed in the summer of 2011 on ten properties owned by the North Coast Land Conservancy (NCLC) in the Neacoxie Creek watershed (please refer to Appendices A & B). Habitat types include stabilized sand dunes dominated by coastal prairie habitat, interdunal wetland swales and lakes, upland Sitka spruce forest, and forested wetlands. Percent composition of each plant community type observed was calculated. Invasive non-native plant species were recorded. Surveys were also conducted for both native and non-native plants in four water bodies owned by NCLC or adjacent to land trust properties. The plant community data that were collected will be used to evaluate baseline ecological conditions in the Neacoxie watershed. Plant communities can be used as indicators of long-term tidal and hydrologic conditions as well as the ecological health of the landscape. Repeated measurements can be used to assess community changes over time and to assess how plant community composition compares to that described for natural conditions. This information will assist the land trust in making science-based stewardship decisions on its properties, and can be used by other landowners to better understand changes occurring in plant communities in similar habitats on their properties as a result of human disturbance (e.g., land development, farming, grazing) and invasion by non-native plants. Close