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• 211. [Article] Rainfall seasonality and an ecohydrological feedback offset the potential impact of climate warming on evapotranspiration and groundwater recharge

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291944-7973.

  Citation × Citation Citation Abstract Copy Title: Rainfall seasonality and an ecohydrological feedback offset the potential impact of climate warming on evapotranspiration and groundwater recharge Author: McDonnell, Jeffrey J., Pangle, Luke A., Gregg, Jillian W. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291944-7973. Title: Rainfall seasonality and an ecohydrological feedback offset the potential impact of climate warming on evapotranspiration and groundwater recharge Author: McDonnell, Jeffrey J., Pangle, Luke A., Gregg, Jillian W. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291944-7973. Close

• 212. [Article] Soil surface CO2 efflux across the climatic gradient of the Oregon Transect for Terrestrial Ecological Research (OTTER)

  Soil CO2 efflux is a major contributor of CO2 to the atmosphere. The rate that CO2 is respired out of the soil is called the soil flux (Fs). Many variables alter Fs. These variables differ drastically ...

  Citation × Citation Citation Abstract Copy Title: Soil surface CO2 efflux across the climatic gradient of the Oregon Transect for Terrestrial Ecological Research (OTTER) Author: Martin, Mark A. Soil CO2 efflux is a major contributor of CO2 to the atmosphere. The rate that CO2 is respired out of the soil is called the soil flux (Fs). Many variables alter Fs. These variables differ drastically in the variety of ecosystems found on the earth. It is important to understand how Fs functions in each ecosystem so future concentrations of CO2 in the atmosphere can be better understood. I studied Fs and its relationship to soil temperature, predawn soil water potential, and aboveground biomass in four ecosystems across the climatic gradient found in the Oregon transect for terrestrial ecological research (OTTER). I found strong relationships between Fs and temperature at the spruce and Douglas-fir sites, and no significant relationship between Fs and temperature at the pine and juniper sites in 2000. Initial water potential data show a relationship with Fs, but more work needs to be done to document it. Title: Soil surface CO2 efflux across the climatic gradient of the Oregon Transect for Terrestrial Ecological Research (OTTER) Author: Martin, Mark A. Soil CO2 efflux is a major contributor of CO2 to the atmosphere. The rate that CO2 is respired out of the soil is called the soil flux (Fs). Many variables alter Fs. These variables differ drastically in the variety of ecosystems found on the earth. It is important to understand how Fs functions in each ecosystem so future concentrations of CO2 in the atmosphere can be better understood. I studied Fs and its relationship to soil temperature, predawn soil water potential, and aboveground biomass in four ecosystems across the climatic gradient found in the Oregon transect for terrestrial ecological research (OTTER). I found strong relationships between Fs and temperature at the spruce and Douglas-fir sites, and no significant relationship between Fs and temperature at the pine and juniper sites in 2000. Initial water potential data show a relationship with Fs, but more work needs to be done to document it. Close

• 213. [Article] Biodiversity Conservation: The Key Is Reducing Meat Consumption

  Access to this item has been restricted by repository administrators at the request of the publisher, Elsevier, until July 29, 2017.

  Citation × Citation Citation Abstract Copy Title: Biodiversity Conservation: The Key Is Reducing Meat Consumption Author: Machovina, Brian, Feeley, Kenneth J., Ripple, William J. Access to this item has been restricted by repository administrators at the request of the publisher, Elsevier, until July 29, 2017. Title: Biodiversity Conservation: The Key Is Reducing Meat Consumption Author: Machovina, Brian, Feeley, Kenneth J., Ripple, William J. Access to this item has been restricted by repository administrators at the request of the publisher, Elsevier, until July 29, 2017. Close

• 214. [Article] A procedure for estimating the carbon budget of terrestrial ecosystems in the former Soviet Union by geographic information system analysis and classification of AVHRR derived Global Vegetation Index

  The purpose of this research was to develop methods for using geographic information system (GIS) analysis and unsupervised classification of Global Vegetation Index (GVI) images to improve carbon budget ...

  Citation × Citation Citation Abstract Copy Title: A procedure for estimating the carbon budget of terrestrial ecosystems in the former Soviet Union by geographic information system analysis and classification of AVHRR derived Global Vegetation Index Author: Gaston, Greg G. The purpose of this research was to develop methods for using geographic information system (GIS) analysis and unsupervised classification of Global Vegetation Index (GVI) images to improve carbon budget estimates of the former Soviet Union (FSU). A GIS was used to locate the geographic distribution and estimate the area of agricultural lands in the FSU. Climatic factors were used to isolate agricultural lands suitable for no-till management. The effects of various tillage practices on the carbon cycle were estimated. Four year average, monthly maximum value GVI composites were clustered on the basis of timing, magnitude, and duration of greenness as recorded by the normalized difference of vegetation index (NDVI). The resulting 42 image classes were identified by a variety of quantitative and qualitative methods including expert assessment by scientists with extensive field experience in the FSU and analysis of temporal NDVI response curves. The image classes appear to accurately delineate vegetation/landcover regions. The percent agricultural land, percent forest cover and percent natural nonforest was estimated for each image class. Equivalent ecosystems described in the Bazilevich carbon data base were used to calculate the carbon cycle parameters forest and natural non-forest ecosystems. Carbon estimates for agricultural lands were calculated from production data. Comparisons between areal estimates of land cover from this research and reported statistics are very good. For example, forested land was estimated at 876 million hectares (MHa) forest statistical data from the FSU estimate commercial forests to be 814 MHa. Total agricultural lands are estimated in research to be 211 MHa, the same as reported by the USDA and very close to the 217 MHa reported by statistics from the FSU. Results from carbon budget analysis include: - Complete conversion of all climatically suitable lands to no-till management would sequester over 3 gigatons (Gt) of carbon in the agricultural soils of the FSU. - Phytomass and net primary productivity (NPP) estimates for forest and non-forest ecosystems compare well with carbon budget estimates that used maps to identify carbon quantifiable regions. Title: A procedure for estimating the carbon budget of terrestrial ecosystems in the former Soviet Union by geographic information system analysis and classification of AVHRR derived Global Vegetation Index Author: Gaston, Greg G. The purpose of this research was to develop methods for using geographic information system (GIS) analysis and unsupervised classification of Global Vegetation Index (GVI) images to improve carbon budget estimates of the former Soviet Union (FSU). A GIS was used to locate the geographic distribution and estimate the area of agricultural lands in the FSU. Climatic factors were used to isolate agricultural lands suitable for no-till management. The effects of various tillage practices on the carbon cycle were estimated. Four year average, monthly maximum value GVI composites were clustered on the basis of timing, magnitude, and duration of greenness as recorded by the normalized difference of vegetation index (NDVI). The resulting 42 image classes were identified by a variety of quantitative and qualitative methods including expert assessment by scientists with extensive field experience in the FSU and analysis of temporal NDVI response curves. The image classes appear to accurately delineate vegetation/landcover regions. The percent agricultural land, percent forest cover and percent natural nonforest was estimated for each image class. Equivalent ecosystems described in the Bazilevich carbon data base were used to calculate the carbon cycle parameters forest and natural non-forest ecosystems. Carbon estimates for agricultural lands were calculated from production data. Comparisons between areal estimates of land cover from this research and reported statistics are very good. For example, forested land was estimated at 876 million hectares (MHa) forest statistical data from the FSU estimate commercial forests to be 814 MHa. Total agricultural lands are estimated in research to be 211 MHa, the same as reported by the USDA and very close to the 217 MHa reported by statistics from the FSU. Results from carbon budget analysis include: - Complete conversion of all climatically suitable lands to no-till management would sequester over 3 gigatons (Gt) of carbon in the agricultural soils of the FSU. - Phytomass and net primary productivity (NPP) estimates for forest and non-forest ecosystems compare well with carbon budget estimates that used maps to identify carbon quantifiable regions. Close

• 215. [Article] Nature and Extent of the Deep Biosphere

  This is the publisher’s final pdf. The published article is copyrighted by Mineralogical Society of America and can be found at: http://www.minsocam.org/.

  Citation × Citation Citation Abstract Copy Title: Nature and Extent of the Deep Biosphere Author: D’Hondt, Steven, Colwell, Frederick S. This is the publisher’s final pdf. The published article is copyrighted by Mineralogical Society of America and can be found at: http://www.minsocam.org/. Title: Nature and Extent of the Deep Biosphere Author: D’Hondt, Steven, Colwell, Frederick S. This is the publisher’s final pdf. The published article is copyrighted by Mineralogical Society of America and can be found at: http://www.minsocam.org/. Close

• 216. [Article] Atmospheric inverse modeling to constrain regional-scale CO₂ budgets at high spatial and temporal resolution

  We present an inverse modeling framework designed to constrain CO2 budgets at regional scales. The approach captures atmospheric transport processes in high spatiotemporal resolution by coupling a mesoscale ...

  Citation × Citation Citation Abstract Copy Title: Atmospheric inverse modeling to constrain regional-scale CO₂ budgets at high spatial and temporal resolution Author: Law, Beverly E., Vickers, Dean, Michalak, Anna M., Turner, David P., Gockede, Mathias We present an inverse modeling framework designed to constrain CO2 budgets at regional scales. The approach captures atmospheric transport processes in high spatiotemporal resolution by coupling a mesoscale model with Lagrangian Stochastic backward trajectories. Terrestrial biosphere CO₂ emissions are generated through a simple diagnostic flux model that splits the net ecosystem exchange into its major components of gross primary productivity and autotrophic and heterotrophic respirations. The modeling framework assimilates state-of-the-art data sets for advected background CO₂ and anthropogenic fossil fuel emissions as well as highly resolved remote sensing products. We introduce a Bayesian inversion setup, optimizing a posteriori flux base rates for surface types that are defined through remote sensing information. This strategy significantly reduces the number of parameters to be optimized compared with solving fluxes for each individual grid cell, thus permitting description of the surface in a very high resolution. The model is tested using CO₂ concentrations measured in the fall and winter of 2006 at two AmeriFlux sites in Oregon. Because this database does not cover a full seasonal cycle, we focus on conducting model sensitivity tests rather than producing quantitative CO₂ flux estimates. Sensitivity tests on the influence of spatial and temporal resolution indicate that optimum results can be obtained using 4 h time steps and grid sizes of 6 km or less. Further tests demonstrate the importance of dividing biome types by ecoregions to capture their different biogeochemical responses to external forcings across climatic gradients. Detailed stand age information was shown to have a positive effect on model performance. Title: Atmospheric inverse modeling to constrain regional-scale CO₂ budgets at high spatial and temporal resolution Author: Law, Beverly E., Vickers, Dean, Michalak, Anna M., Turner, David P., Gockede, Mathias We present an inverse modeling framework designed to constrain CO2 budgets at regional scales. The approach captures atmospheric transport processes in high spatiotemporal resolution by coupling a mesoscale model with Lagrangian Stochastic backward trajectories. Terrestrial biosphere CO₂ emissions are generated through a simple diagnostic flux model that splits the net ecosystem exchange into its major components of gross primary productivity and autotrophic and heterotrophic respirations. The modeling framework assimilates state-of-the-art data sets for advected background CO₂ and anthropogenic fossil fuel emissions as well as highly resolved remote sensing products. We introduce a Bayesian inversion setup, optimizing a posteriori flux base rates for surface types that are defined through remote sensing information. This strategy significantly reduces the number of parameters to be optimized compared with solving fluxes for each individual grid cell, thus permitting description of the surface in a very high resolution. The model is tested using CO₂ concentrations measured in the fall and winter of 2006 at two AmeriFlux sites in Oregon. Because this database does not cover a full seasonal cycle, we focus on conducting model sensitivity tests rather than producing quantitative CO₂ flux estimates. Sensitivity tests on the influence of spatial and temporal resolution indicate that optimum results can be obtained using 4 h time steps and grid sizes of 6 km or less. Further tests demonstrate the importance of dividing biome types by ecoregions to capture their different biogeochemical responses to external forcings across climatic gradients. Detailed stand age information was shown to have a positive effect on model performance. Close

• 217. [Article] What eddy-covariance measurements tell us about prior land flux errors in CO₂-flux inversion schemes

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gb/index.shtml.

  Citation × Citation Citation Abstract Copy Title: What eddy-covariance measurements tell us about prior land flux errors in CO₂-flux inversion schemes Author: Moors, Eddy J., Cescatti, Alessandro, Dolman, A. Johannes, Bocquet, Marc, Maignan, Fabienne, Chevallier, Frederic, Margolis, Hank A., Wang, Tao, Ciais, Philippe, Arain, M. Altaf, Law, Beverly E., Chen, Jiquan, Montagnani, Leonardo This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gb/index.shtml. Title: What eddy-covariance measurements tell us about prior land flux errors in CO₂-flux inversion schemes Author: Moors, Eddy J., Cescatti, Alessandro, Dolman, A. Johannes, Bocquet, Marc, Maignan, Fabienne, Chevallier, Frederic, Margolis, Hank A., Wang, Tao, Ciais, Philippe, Arain, M. Altaf, Law, Beverly E., Chen, Jiquan, Montagnani, Leonardo This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gb/index.shtml. Close

• 218. [Article] N₂-Fixing Red Alder Indirectly Accelerates Ecosystem Nitrogen Cycling

  This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://www.springerlink.com/content/101552/. To the best of our knowledge, one or more authors of ...

  Citation × Citation Citation Abstract Copy Title: N₂-Fixing Red Alder Indirectly Accelerates Ecosystem Nitrogen Cycling Author: Matkins, Joselin J., Hibbs, David E., Perakis, Steven S. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://www.springerlink.com/content/101552/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: N₂-Fixing Red Alder Indirectly Accelerates Ecosystem Nitrogen Cycling Author: Matkins, Joselin J., Hibbs, David E., Perakis, Steven S. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://www.springerlink.com/content/101552/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 219. [Article] The ecology of riparian ecosystems of Northeast Oregon : shrub recovery at Meadow Creek and the structure and biomass of headwater Upper Grande Ronde ecosystems

  Riparian ecosystems play numerous and essential roles related to the quality and flow of water, and food/habitat for fish, and varieties of wildlife. Due to lateral and linear linkages throughout the landscape, ...

  Citation × Citation Citation Abstract Copy Title: The ecology of riparian ecosystems of Northeast Oregon : shrub recovery at Meadow Creek and the structure and biomass of headwater Upper Grande Ronde ecosystems Author: Case, Richard L. Riparian ecosystems play numerous and essential roles related to the quality and flow of water, and food/habitat for fish, and varieties of wildlife. Due to lateral and linear linkages throughout the landscape, these zones influence the integrity of the terrestrial as well as the entire aquatic-riverine ecosystem. Since Euro-American settlement in the West, the structure and condition of many riparian ecosystems has been significantly altered. To provide tools and an ecological perspective related to riparian restoration and management, and to document late 20th century headwater riparian structure and biomass in the Upper Grande Ronde Basin, this research project was undertaken. At Meadow Creek, the response of riparian hardwood species to the termination of livestock grazing was quantified. Regression equations were developed to predict shrub biomass. Permanently marked hardwood plants were measured annually to quantify parameters of growth (height, crown area, mainstem diameter, number of stems, biomass). Permanent belt transects on gravel bars were utilized to quantify rates of shrub establishment. Elk/deer-proof exclosures allowed the quantification of the browsing influence of wild ungulates. In 1991, initial shrub heights and densities reflected decades of grazing pressure. Mean heights of515 woody plants (14 species) was 47 cm and densities on gravel bars averaged 10.7 plants/100m². After two seasons without livestock grazing, mean crown volumes of willows (Salix spp.) increased 550% inside of wild ungulate exclosures and 195% outside, black cottonwood (Populus trichocarpa) 773% inside and 808% outside, and thin-leaf alder (Almis incana) 1046% inside and 198% outside, respectively. Willows were significantly impeded (p<0.Ol) mule deer and Rocky Mountain elk, alder samples were too small to statistically test, and cottonwood was not significantly impeded. However, impacts by deer and elk may be exaggerated due to high densities and the ungulate density-dynamics unique within the 77 km² Starkey Experimental Forest big-game enclosure surrounding the study site. Establishment rates are low at this time, i.e., only 10% of previously suppressed willows produced catkins. Although in transects densities increased by 5 new woody plants/lOOm² (50m of streambank). Other non-anthropogenic factors influencing the recovery of shrubs, included beaver which removed mainstems from 20% of willows, 11% of thin-leaf alder, and 4% of black cottonwood, and active insect defoliation which was noted on 16% of willows, 7% of thin-leaf alder, and 0% of black cottonwood. Crude protein levels measured in willow and alder leaves was relatively high (16.1 to 16.3%) helping to explain their palatability and use by wild and domestic herbivores. Few studies have quantified biomass, structure and composition of headwater riparian ecosystems. Data such as this are important given their dominant roles in ecosystem biodiversity, and aquatic function. To document relatively intact forested headwater ripanan conditions in the Upper Grande Ronde Basin, the biomass, structure and composition along six headwater reaches was quantified. Sampling was done using a nested belt transect/plot arrangement along 500 meter reaches. Total aboveground biomass (TAGB) ranged from 203 to 261 Mg/ha, with overstory conifers contributing 101 to 177 Mg/ha. Living understory components (saplings, seedlings, shrubs, and herbs) comprised 5 to 18 Mg/ha (2 to 9% of TAGB), while forest floor detrital accumulations comprised 65 to 101 Mg/ha (29 to 42% of TAGB). Average shade per day for July, 1993 ranged between 53% and 75%, reducing the unshaded solar energy potential of 2390 Mj/day to between 680 and 1280 Mj/day striking each m² of stream surface. This baseline reference information can serve in multi-disciplined research, as well as, be a basis for long term studies of natural systems responding to changing climate and different resource management scenarios. Title: The ecology of riparian ecosystems of Northeast Oregon : shrub recovery at Meadow Creek and the structure and biomass of headwater Upper Grande Ronde ecosystems Author: Case, Richard L. Riparian ecosystems play numerous and essential roles related to the quality and flow of water, and food/habitat for fish, and varieties of wildlife. Due to lateral and linear linkages throughout the landscape, these zones influence the integrity of the terrestrial as well as the entire aquatic-riverine ecosystem. Since Euro-American settlement in the West, the structure and condition of many riparian ecosystems has been significantly altered. To provide tools and an ecological perspective related to riparian restoration and management, and to document late 20th century headwater riparian structure and biomass in the Upper Grande Ronde Basin, this research project was undertaken. At Meadow Creek, the response of riparian hardwood species to the termination of livestock grazing was quantified. Regression equations were developed to predict shrub biomass. Permanently marked hardwood plants were measured annually to quantify parameters of growth (height, crown area, mainstem diameter, number of stems, biomass). Permanent belt transects on gravel bars were utilized to quantify rates of shrub establishment. Elk/deer-proof exclosures allowed the quantification of the browsing influence of wild ungulates. In 1991, initial shrub heights and densities reflected decades of grazing pressure. Mean heights of515 woody plants (14 species) was 47 cm and densities on gravel bars averaged 10.7 plants/100m². After two seasons without livestock grazing, mean crown volumes of willows (Salix spp.) increased 550% inside of wild ungulate exclosures and 195% outside, black cottonwood (Populus trichocarpa) 773% inside and 808% outside, and thin-leaf alder (Almis incana) 1046% inside and 198% outside, respectively. Willows were significantly impeded (p<0.Ol) mule deer and Rocky Mountain elk, alder samples were too small to statistically test, and cottonwood was not significantly impeded. However, impacts by deer and elk may be exaggerated due to high densities and the ungulate density-dynamics unique within the 77 km² Starkey Experimental Forest big-game enclosure surrounding the study site. Establishment rates are low at this time, i.e., only 10% of previously suppressed willows produced catkins. Although in transects densities increased by 5 new woody plants/lOOm² (50m of streambank). Other non-anthropogenic factors influencing the recovery of shrubs, included beaver which removed mainstems from 20% of willows, 11% of thin-leaf alder, and 4% of black cottonwood, and active insect defoliation which was noted on 16% of willows, 7% of thin-leaf alder, and 0% of black cottonwood. Crude protein levels measured in willow and alder leaves was relatively high (16.1 to 16.3%) helping to explain their palatability and use by wild and domestic herbivores. Few studies have quantified biomass, structure and composition of headwater riparian ecosystems. Data such as this are important given their dominant roles in ecosystem biodiversity, and aquatic function. To document relatively intact forested headwater ripanan conditions in the Upper Grande Ronde Basin, the biomass, structure and composition along six headwater reaches was quantified. Sampling was done using a nested belt transect/plot arrangement along 500 meter reaches. Total aboveground biomass (TAGB) ranged from 203 to 261 Mg/ha, with overstory conifers contributing 101 to 177 Mg/ha. Living understory components (saplings, seedlings, shrubs, and herbs) comprised 5 to 18 Mg/ha (2 to 9% of TAGB), while forest floor detrital accumulations comprised 65 to 101 Mg/ha (29 to 42% of TAGB). Average shade per day for July, 1993 ranged between 53% and 75%, reducing the unshaded solar energy potential of 2390 Mj/day to between 680 and 1280 Mj/day striking each m² of stream surface. This baseline reference information can serve in multi-disciplined research, as well as, be a basis for long term studies of natural systems responding to changing climate and different resource management scenarios. Close