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• 91. [Article] Models relating to terrestrial mineral cycling : progress report

  Although no formal project in mineral cycling was defined for 1972, three modeling efforts were begun: calcium cycling at Cedar River, litter decomposition, and miombo ecosystem. The calcium cycling model ...

  Citation × Citation Citation Abstract Copy Title: Models relating to terrestrial mineral cycling : progress report Author: Strand, Mary Ann Sall, U.S. International Biological Program. Coniferous Forest Biome, University of Washington Although no formal project in mineral cycling was defined for 1972, three modeling efforts were begun: calcium cycling at Cedar River, litter decomposition, and miombo ecosystem. The calcium cycling model is a simple compartment model and was developed as a practice exercise. It demonstrates the inadequacy of linear-donor control formulation for describing the transfer of a non-limiting nutrient. The litter decomposition model is used to examine the processes related to the incorporation of organic material into the soil horizons. It is a nonlinear model using difference equations on a one-week time resolution. It has not yet been coupled to mineral release. The miombo ecosystem model follows the flux of carbon through a central African ecosystem. It demonstrates the seasonal changes in biomass in various vegetation and animal components. Title: Models relating to terrestrial mineral cycling : progress report Author: Strand, Mary Ann Sall, U.S. International Biological Program. Coniferous Forest Biome, University of Washington Although no formal project in mineral cycling was defined for 1972, three modeling efforts were begun: calcium cycling at Cedar River, litter decomposition, and miombo ecosystem. The calcium cycling model is a simple compartment model and was developed as a practice exercise. It demonstrates the inadequacy of linear-donor control formulation for describing the transfer of a non-limiting nutrient. The litter decomposition model is used to examine the processes related to the incorporation of organic material into the soil horizons. It is a nonlinear model using difference equations on a one-week time resolution. It has not yet been coupled to mineral release. The miombo ecosystem model follows the flux of carbon through a central African ecosystem. It demonstrates the seasonal changes in biomass in various vegetation and animal components. Close

• 92. [Article] Terrestrial amphibian distribution, habitat associations and downed wood temperature profiles in managed headwater forests with riparian buffers in the Oregon Coast Range

  Western forests have become increasingly fragmented landscapes dominated by young stands. Given that western Oregon forests largely consist of headwater systems, there is a need to better understand how ...

  Citation × Citation Citation Abstract Copy Title: Terrestrial amphibian distribution, habitat associations and downed wood temperature profiles in managed headwater forests with riparian buffers in the Oregon Coast Range Author: Kluber, Matthew R. Western forests have become increasingly fragmented landscapes dominated by young stands. Given that western Oregon forests largely consist of headwater systems, there is a need to better understand how headwater forest taxa and their habitats are impacted by forest management practices. Several amphibian species associated with forested headwater systems have emerged as management concerns. Forest management strategies, such as harvests that remove only part of the canopy and retention of riparian buffer strips, may help ameliorate some of the negative effects on amphibians in managed forests. Pre-existing site conditions, such as legacy downed wood, also may play a role in buffering the impacts of silvicultural practices on terrestrial amphibians. Downed wood is an important habitat component for many amphibians, because the cool, moist microclimates of downed wood can provide refugia for terrestrial amphibians during warmer summer months. However, downed wood habitat suitability is another emerging concern as the rate of input and size of downed wood declines in managed forests. As part of the USDI Bureau of Land Managements Density Management Study, we investigated how untreated streamside buffers modify impacts of upland thinning on headwater forest terrestrial amphibians and their habitat at three sites in the Oregon Coast Range. To further assess habitat associations of these animals, we conducted a field experiment to address amphibian cover use, including downed wood, moss and coarse and fine substrates. In addition, we examined how temperature profiles inside small- and large-diameter downed wood and soil temperatures differed from ambient air temperatures. Temperatures of wood and soil were monitored at different slope positions (near streams and upslope) and overstory regimes (thinned and unthinned stands) to assess potential habitat suitability and buffering capabilities against seasonal temperature extremes for plethodontid salamanders. Our results suggest that pre-existing site conditions (e.g., amount of rocky or fine substrate) play an important role in determining the response of terrestrial amphibians to upland forest thinning. However, retention of stream buffers is important in maintaining unaltered stream and riparian conditions. Moderate thinning and preservation of vital habitat in riparian and nearby upland areas by way of variable-width buffers (15 m minimum width) may be sufficient in maintaining suitable habitat and microclimatic conditions vital to amphibian assemblages in managed headwater forests. Additionally, logs of a wide size range and soils may provide sufficient protection against thermal extremes harmful to plethodontid salamanders in thinned stands with limited overstory. However, this alone cannot support plethodontid salamanders. These salamanders require exposed areas (e.g., leaf litter, soil surface, rock faces) where much of their foraging and well as courtship occurs. Partial retention of the canopy through moderate thinning coupled with variable-width riparain buffers that may increase in width when suitable terrestrial habitat is encountered, may provide sufficient microhabitat, microclimate, and protection in maintaining terrestrial amphibian assemblages in managed headwater forests. Title: Terrestrial amphibian distribution, habitat associations and downed wood temperature profiles in managed headwater forests with riparian buffers in the Oregon Coast Range Author: Kluber, Matthew R. Western forests have become increasingly fragmented landscapes dominated by young stands. Given that western Oregon forests largely consist of headwater systems, there is a need to better understand how headwater forest taxa and their habitats are impacted by forest management practices. Several amphibian species associated with forested headwater systems have emerged as management concerns. Forest management strategies, such as harvests that remove only part of the canopy and retention of riparian buffer strips, may help ameliorate some of the negative effects on amphibians in managed forests. Pre-existing site conditions, such as legacy downed wood, also may play a role in buffering the impacts of silvicultural practices on terrestrial amphibians. Downed wood is an important habitat component for many amphibians, because the cool, moist microclimates of downed wood can provide refugia for terrestrial amphibians during warmer summer months. However, downed wood habitat suitability is another emerging concern as the rate of input and size of downed wood declines in managed forests. As part of the USDI Bureau of Land Managements Density Management Study, we investigated how untreated streamside buffers modify impacts of upland thinning on headwater forest terrestrial amphibians and their habitat at three sites in the Oregon Coast Range. To further assess habitat associations of these animals, we conducted a field experiment to address amphibian cover use, including downed wood, moss and coarse and fine substrates. In addition, we examined how temperature profiles inside small- and large-diameter downed wood and soil temperatures differed from ambient air temperatures. Temperatures of wood and soil were monitored at different slope positions (near streams and upslope) and overstory regimes (thinned and unthinned stands) to assess potential habitat suitability and buffering capabilities against seasonal temperature extremes for plethodontid salamanders. Our results suggest that pre-existing site conditions (e.g., amount of rocky or fine substrate) play an important role in determining the response of terrestrial amphibians to upland forest thinning. However, retention of stream buffers is important in maintaining unaltered stream and riparian conditions. Moderate thinning and preservation of vital habitat in riparian and nearby upland areas by way of variable-width buffers (15 m minimum width) may be sufficient in maintaining suitable habitat and microclimatic conditions vital to amphibian assemblages in managed headwater forests. Additionally, logs of a wide size range and soils may provide sufficient protection against thermal extremes harmful to plethodontid salamanders in thinned stands with limited overstory. However, this alone cannot support plethodontid salamanders. These salamanders require exposed areas (e.g., leaf litter, soil surface, rock faces) where much of their foraging and well as courtship occurs. Partial retention of the canopy through moderate thinning coupled with variable-width riparain buffers that may increase in width when suitable terrestrial habitat is encountered, may provide sufficient microhabitat, microclimate, and protection in maintaining terrestrial amphibian assemblages in managed headwater forests. Close

• 93. [Article] Can fuel-reduction treatments really increase forest carbon storage in the western US by reducing future fire emissions?

  NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/s1SWsO

  Citation × Citation Citation Abstract Copy Title: Can fuel-reduction treatments really increase forest carbon storage in the western US by reducing future fire emissions? Author: Harmon, Mark E., Campbell, John L., Mitchell, Stephen R. NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/s1SWsO Title: Can fuel-reduction treatments really increase forest carbon storage in the western US by reducing future fire emissions? Author: Harmon, Mark E., Campbell, John L., Mitchell, Stephen R. NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/s1SWsO Close

• 94. [Article] Study on integrating surveys of terrestrial natural resources : the Oregon Demonstration Project

  An interagency project demonstrated the feasibility of integrating Federal surveys of terrestrial natural resources and offers a vision for that integration. At locations selected from forest inventory ...

  Citation × Citation Citation Abstract Copy Title: Study on integrating surveys of terrestrial natural resources : the Oregon Demonstration Project Author: House, Carol C., Williams, William, Geissler, Paul H., Goebel, J. Jeffery, Olsen, Anthony R., Schreuder, Hans T., National Health and Environmental Effects Research Laboratory (U.S.) An interagency project demonstrated the feasibility of integrating Federal surveys of terrestrial natural resources and offers a vision for that integration. At locations selected from forest inventory and analysis, National forest system Region 6, and national resources inventory surveys in a six-county area in Northern Oregon, experienced teams interpreted and made measurements on aerial photographs and measured on-site a range of soil, vegetation and animal attributes. The project demonstrated the feasibility of conducting a combined FIA/NFS/NRI survey at the substate level and suggests an approach that will preserve the utility of the critical historic information from these surveys. Title: Study on integrating surveys of terrestrial natural resources : the Oregon Demonstration Project Author: House, Carol C., Williams, William, Geissler, Paul H., Goebel, J. Jeffery, Olsen, Anthony R., Schreuder, Hans T., National Health and Environmental Effects Research Laboratory (U.S.) An interagency project demonstrated the feasibility of integrating Federal surveys of terrestrial natural resources and offers a vision for that integration. At locations selected from forest inventory and analysis, National forest system Region 6, and national resources inventory surveys in a six-county area in Northern Oregon, experienced teams interpreted and made measurements on aerial photographs and measured on-site a range of soil, vegetation and animal attributes. The project demonstrated the feasibility of conducting a combined FIA/NFS/NRI survey at the substate level and suggests an approach that will preserve the utility of the critical historic information from these surveys. Close

• 95. [Article] Marine Nitrogen Subsidies to Terrestrial Systems: Transport Through Wrack Deposition

  Fluctuations in one system affect adjacent systems; mechanistic understanding of linkages helps conservation efforts be more effective by focusing on influential species and areas that facilitate connections ...

  Citation × Citation Citation Abstract Copy Title: Marine Nitrogen Subsidies to Terrestrial Systems: Transport Through Wrack Deposition Author: Traylor, Andrew Fluctuations in one system affect adjacent systems; mechanistic understanding of linkages helps conservation efforts be more effective by focusing on influential species and areas that facilitate connections between ecosystems. This study explored marine-derived nutrient inputs to adjacent terrestrial communities. We quantified wrack (seaweed and other organic matter) deposition at sites (Shi Shi Beach (SS), Giants Graveyard (GG), and Cape Alava (CA)) along the outer Olympic Peninsula, WA that created potential nitrogen sources serving nearby terrestrial communities. We found five dominant species of seaweed in wrack deposits with variation in dominance and biomass of wrack within sites and between sites. We attribute within site variation to flotation adaptations of species and intersite variation to differences in geomorphology and source population. Due to abundance and stable nitrogen concentrations over time, Phyllospadix was influential to total nitrogen deposition from mean higher water (MHHW) to ~ 1.3m above MHHW, however above this elevation Fucus, Macrocystis, and Nereocystis were likely influential species. Cape Alava showed highest total nitrogen deposit per m² followed by GG and SS (CA > SS ~=GG; =65.8; p<0.0001). Our study shows considerable amounts of nitrogen are deposited on beaches through wrack and total nitrogen deposits is influenced by particular species of seaweeds and percent cover of deposits. Title: Marine Nitrogen Subsidies to Terrestrial Systems: Transport Through Wrack Deposition Author: Traylor, Andrew Fluctuations in one system affect adjacent systems; mechanistic understanding of linkages helps conservation efforts be more effective by focusing on influential species and areas that facilitate connections between ecosystems. This study explored marine-derived nutrient inputs to adjacent terrestrial communities. We quantified wrack (seaweed and other organic matter) deposition at sites (Shi Shi Beach (SS), Giants Graveyard (GG), and Cape Alava (CA)) along the outer Olympic Peninsula, WA that created potential nitrogen sources serving nearby terrestrial communities. We found five dominant species of seaweed in wrack deposits with variation in dominance and biomass of wrack within sites and between sites. We attribute within site variation to flotation adaptations of species and intersite variation to differences in geomorphology and source population. Due to abundance and stable nitrogen concentrations over time, Phyllospadix was influential to total nitrogen deposition from mean higher water (MHHW) to ~ 1.3m above MHHW, however above this elevation Fucus, Macrocystis, and Nereocystis were likely influential species. Cape Alava showed highest total nitrogen deposit per m² followed by GG and SS (CA > SS ~=GG; =65.8; p<0.0001). Our study shows considerable amounts of nitrogen are deposited on beaches through wrack and total nitrogen deposits is influenced by particular species of seaweeds and percent cover of deposits. Close

• 96. [Article] Chronic nitrogen additions suppress decomposition and sequester soil carbon in temperate forests

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer ...

  Citation × Citation Citation Abstract Copy Title: Chronic nitrogen additions suppress decomposition and sequester soil carbon in temperate forests Author: Lajtha, K., Nadelhoffer, K., Caldwell, B. A., Frey, S. D., et al., Ollinger, S. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10533. Title: Chronic nitrogen additions suppress decomposition and sequester soil carbon in temperate forests Author: Lajtha, K., Nadelhoffer, K., Caldwell, B. A., Frey, S. D., et al., Ollinger, S. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10533. Close

• 97. [Article] A Terrestrial-Aquatic Food Web Subsidy is Potentially Mediated by Multiple Predator Effects on an Arboreal Crab

  Terrestrial-aquatic food web subsidies are known to affect food web structure, ecosystem productivity, and stability of recipient habitats. This study describes a prey flux across the land–water interface ...

  Citation × Citation Citation Abstract Copy Title: A Terrestrial-Aquatic Food Web Subsidy is Potentially Mediated by Multiple Predator Effects on an Arboreal Crab Author: Yeager, Lauren A., Stoner, Elizabeth W., Peters, Joseph R., Layman, Craig A. Year: 2015 Terrestrial-aquatic food web subsidies are known to affect food web structure, ecosystem productivity, and stability of recipient habitats. This study describes a prey flux across the land–water interface associated with a behavioral response to multiple predators. Specifically, mangrove tree crabs (Aratus pisonii, hereafter Aratus) are primarily arboreal, but may jump off mangrove trees to escape avian predators, making them vulnerable to fish predation. Mesocosm experiments, field observations, and tethering assays were used to investigate behavioral responses, habitat shifts, and risk for Aratus associated with these two predator types. In the field, Aratus spent most of their time above the water on mangroves, where risk is lowest. In response to simulated bird strikes in mesocosm trials, crabs jumped off trees to escape imminent risk, and spent more time in and near the water, enhancing risk of fish predation. Fish attacks on crabs were nearly three times greater in treatments with simulated bird attacks. In addition, empirical diet data was used to examine the importance of Aratus as a prey item for a fish predator. Aratus represented up to 29% of diet by volume for one of the most common mesopredators in the Caribbean (gray snapper Lutjanus griseus), with the proportion varying greatly across space. Because Aratus consume mangrove-derived carbon, their consumption by aquatic predators represents another pathway by which mangrove production may be incorporated into aquatic food webs. These data suggest how the nexus of behavioral and food web ecology may provide for new perspectives on energy flow between ecosystems. Title: A Terrestrial-Aquatic Food Web Subsidy is Potentially Mediated by Multiple Predator Effects on an Arboreal Crab Author: Yeager, Lauren A., Stoner, Elizabeth W., Peters, Joseph R., Layman, Craig A. Year: 2015 Terrestrial-aquatic food web subsidies are known to affect food web structure, ecosystem productivity, and stability of recipient habitats. This study describes a prey flux across the land–water interface associated with a behavioral response to multiple predators. Specifically, mangrove tree crabs (Aratus pisonii, hereafter Aratus) are primarily arboreal, but may jump off mangrove trees to escape avian predators, making them vulnerable to fish predation. Mesocosm experiments, field observations, and tethering assays were used to investigate behavioral responses, habitat shifts, and risk for Aratus associated with these two predator types. In the field, Aratus spent most of their time above the water on mangroves, where risk is lowest. In response to simulated bird strikes in mesocosm trials, crabs jumped off trees to escape imminent risk, and spent more time in and near the water, enhancing risk of fish predation. Fish attacks on crabs were nearly three times greater in treatments with simulated bird attacks. In addition, empirical diet data was used to examine the importance of Aratus as a prey item for a fish predator. Aratus represented up to 29% of diet by volume for one of the most common mesopredators in the Caribbean (gray snapper Lutjanus griseus), with the proportion varying greatly across space. Because Aratus consume mangrove-derived carbon, their consumption by aquatic predators represents another pathway by which mangrove production may be incorporated into aquatic food webs. These data suggest how the nexus of behavioral and food web ecology may provide for new perspectives on energy flow between ecosystems. Close

• 98. [Article] Spatial and temporal effects of atmospheric deposition, climate, and land management on forest nutrient cycling and biodiversity

  Emissions largely associated with the combustion of fossil fuels and agriculture has caused elevated atmospheric deposition of nitrogen (N) and sulfur (S) throughout much of the developed world. Increased ...

  Citation × Citation Citation Abstract Copy Title: Spatial and temporal effects of atmospheric deposition, climate, and land management on forest nutrient cycling and biodiversity Author: McDonnell, Todd C. Emissions largely associated with the combustion of fossil fuels and agriculture has caused elevated atmospheric deposition of nitrogen (N) and sulfur (S) throughout much of the developed world. Increased atmospheric deposition of N and S can lead to soil and surface water acidification and affect forest soil nutrient supply. The critical load (CL) of atmospheric deposition is the level of deposition below which significant harm to ecosystems is not likely to occur. The critical load provides an understanding of the extent to which terrestrial and aquatic systems may be affected by air pollution at present or in the future. This research implements novel methods for generating CL estimates of N and S deposition and evaluates spatial and temporal trends in soil chemistry and plant biodiversity with respect to future climate and land management scenarios. Results are presented in the context of chemical thresholds known to be associated with adverse impacts to terrestrial and aquatic biota of the southern Appalachian Mountains and high elevation Colorado Rocky Mountains. Title: Spatial and temporal effects of atmospheric deposition, climate, and land management on forest nutrient cycling and biodiversity Author: McDonnell, Todd C. Emissions largely associated with the combustion of fossil fuels and agriculture has caused elevated atmospheric deposition of nitrogen (N) and sulfur (S) throughout much of the developed world. Increased atmospheric deposition of N and S can lead to soil and surface water acidification and affect forest soil nutrient supply. The critical load (CL) of atmospheric deposition is the level of deposition below which significant harm to ecosystems is not likely to occur. The critical load provides an understanding of the extent to which terrestrial and aquatic systems may be affected by air pollution at present or in the future. This research implements novel methods for generating CL estimates of N and S deposition and evaluates spatial and temporal trends in soil chemistry and plant biodiversity with respect to future climate and land management scenarios. Results are presented in the context of chemical thresholds known to be associated with adverse impacts to terrestrial and aquatic biota of the southern Appalachian Mountains and high elevation Colorado Rocky Mountains. Close

• 99. [Article] Global vegetation monitoring: towards a sustainable technobiosphere

  The concept of sustainable resource management can be applied at multiple scales. Monitoring is an essential component of sustainable natural resource management schemes, and as we begin to confront the ...

  Citation × Citation Citation Abstract Copy Title: Global vegetation monitoring: towards a sustainable technobiosphere Author: Turner, David P. The concept of sustainable resource management can be applied at multiple scales. Monitoring is an essential component of sustainable natural resource management schemes, and as we begin to confront the need to manage natural resources at the global scale, the importance of monitoring at the global scale is also growing. The combination of satellite remote sensing, in situ measurements, and simulation modeling has the potential to deliver an annual assessment of status and trends for several measures of terrestrial biosphere structure and function relevant to sustainability. However, there is, as yet, no internationally coordinated effort in place to perform that analysis. Synthesis activity of that kind would support the development of global environmental governance institutions, including both nongovernmental organizations and international bodies. Title: Global vegetation monitoring: towards a sustainable technobiosphere Author: Turner, David P. The concept of sustainable resource management can be applied at multiple scales. Monitoring is an essential component of sustainable natural resource management schemes, and as we begin to confront the need to manage natural resources at the global scale, the importance of monitoring at the global scale is also growing. The combination of satellite remote sensing, in situ measurements, and simulation modeling has the potential to deliver an annual assessment of status and trends for several measures of terrestrial biosphere structure and function relevant to sustainability. However, there is, as yet, no internationally coordinated effort in place to perform that analysis. Synthesis activity of that kind would support the development of global environmental governance institutions, including both nongovernmental organizations and international bodies. Close

• 100. [Article] Specific consensus statement on the likely impacts of climate change on the Pacific Northwest

  The signatories of this statement seek to describe the state of scientific knowledge regarding likely impacts of climate change to the Pacific Northwest region. The intent is to assist Governor Kulongoski’s ...

  Citation × Citation Citation Abstract Copy Title: Specific consensus statement on the likely impacts of climate change on the Pacific Northwest The signatories of this statement seek to describe the state of scientific knowledge regarding likely impacts of climate change to the Pacific Northwest region. The intent is to assist Governor Kulongoski’s Advisory Group on Global Warming in its task of developing a greenhouse gas emission reduction strategy for Oregon. The signatories agree that climate change is underway and that it is having global effects as well as impacts in the Pacific Northwest region. Title: Specific consensus statement on the likely impacts of climate change on the Pacific Northwest The signatories of this statement seek to describe the state of scientific knowledge regarding likely impacts of climate change to the Pacific Northwest region. The intent is to assist Governor Kulongoski’s Advisory Group on Global Warming in its task of developing a greenhouse gas emission reduction strategy for Oregon. The signatories agree that climate change is underway and that it is having global effects as well as impacts in the Pacific Northwest region. Close