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• 91. [Article] Seasonality and drought effects of Amazonian forests observed from multi-angle satellite data

  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 Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Seasonality and drought effects of Amazonian forests observed from multi-angle satellite data Author: Hilker, Thomas, et al., de Moura, Yhasmin Mendes, Lyapustin, Alexei I., Resende de Sousa, Célio Helder 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 Elsevier and can be found at: http://www.journals.elsevier.com/remote-sensing-of-environment/ Title: Seasonality and drought effects of Amazonian forests observed from multi-angle satellite data Author: Hilker, Thomas, et al., de Moura, Yhasmin Mendes, Lyapustin, Alexei I., Resende de Sousa, Célio Helder 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 Elsevier and can be found at: http://www.journals.elsevier.com/remote-sensing-of-environment/ Close

• 92. [Article] Optimal irrigation management : a framework, model, and application for optimizing irrigation when supplies are limited

  Many regions in North America are experiencing water shortages, and these conditions are expected to worsen. The next generation of irrigation scheduling applications must therefore be capable of providing ...

  Citation × Citation Citation Abstract Copy Title: Optimal irrigation management : a framework, model, and application for optimizing irrigation when supplies are limited Author: Hillyer, Charles C. (Charles Carter) Many regions in North America are experiencing water shortages, and these conditions are expected to worsen. The next generation of irrigation scheduling applications must therefore be capable of providing operational advice in support of deficit irrigation strategies. However, the theoretical, technical, and practical challenges associated with deficit irrigation scheduling are far more complex than conventional (full) irrigation. This dissertation presents three distinct systems for addressing the analytical challenges of deficit irrigation management. The first section of the dissertation presents a simulation framework for agro-ecological simulation. The objective was to develop a method to enable the assembly of simulation models from previously and independently developed component models. Based on a requirements analysis of existing simulation models we developed the ModCom simulation framework. ModCom provides a set of interface specifications that describe components in a simulation. ModCom also provides implementations of the core simulation services. The framework interfaces use well-defined binary standards and allows developers to implement the interfaces using a broad range of computer languages. The Second section describes the Irrigation Efficiency Model (IEM). IEM explicitly analyzes irrigation efficiency, accounts for spatial variability of soil properties and irrigation uniformity, performs simultaneous scheduling for all fields in the farm, accounts for energy use and its associated costs, and uses both ET and soil moisture measurements to enhance the accuracy of the irrigation schedules. IEM was developed specifically for implementing Deficit Irrigation and therefore includes analyses that go beyond the requirements of conventional irrigation scheduling. The third section describes Irrigation Management Online (IMO), a web application for optimum irrigation management. This system uses IEM to generate and deliver irrigation scheduling recommendations. IMO has been developed specifically to support irrigation management when either water supplies or delivery system capacities are limited. To mitigate the complexities of irrigation constraints the system has been designed so that the irrigation manager is an integral part of the irrigation optimization procedure. The final section outlines some of the key challenges that the next generation of schedulers must overcome in order to meet the needs of agricultural irrigation in an increasingly water short future. In addition, this section will discuss how irrigation advisory programs will need to operate differently in terms of what they do and how they do it. Title: Optimal irrigation management : a framework, model, and application for optimizing irrigation when supplies are limited Author: Hillyer, Charles C. (Charles Carter) Many regions in North America are experiencing water shortages, and these conditions are expected to worsen. The next generation of irrigation scheduling applications must therefore be capable of providing operational advice in support of deficit irrigation strategies. However, the theoretical, technical, and practical challenges associated with deficit irrigation scheduling are far more complex than conventional (full) irrigation. This dissertation presents three distinct systems for addressing the analytical challenges of deficit irrigation management. The first section of the dissertation presents a simulation framework for agro-ecological simulation. The objective was to develop a method to enable the assembly of simulation models from previously and independently developed component models. Based on a requirements analysis of existing simulation models we developed the ModCom simulation framework. ModCom provides a set of interface specifications that describe components in a simulation. ModCom also provides implementations of the core simulation services. The framework interfaces use well-defined binary standards and allows developers to implement the interfaces using a broad range of computer languages. The Second section describes the Irrigation Efficiency Model (IEM). IEM explicitly analyzes irrigation efficiency, accounts for spatial variability of soil properties and irrigation uniformity, performs simultaneous scheduling for all fields in the farm, accounts for energy use and its associated costs, and uses both ET and soil moisture measurements to enhance the accuracy of the irrigation schedules. IEM was developed specifically for implementing Deficit Irrigation and therefore includes analyses that go beyond the requirements of conventional irrigation scheduling. The third section describes Irrigation Management Online (IMO), a web application for optimum irrigation management. This system uses IEM to generate and deliver irrigation scheduling recommendations. IMO has been developed specifically to support irrigation management when either water supplies or delivery system capacities are limited. To mitigate the complexities of irrigation constraints the system has been designed so that the irrigation manager is an integral part of the irrigation optimization procedure. The final section outlines some of the key challenges that the next generation of schedulers must overcome in order to meet the needs of agricultural irrigation in an increasingly water short future. In addition, this section will discuss how irrigation advisory programs will need to operate differently in terms of what they do and how they do it. Close

• 93. [Article] Vertebrates, arthropods, and invasive plants : an investigation of the top-down and bottom-up interactions of multiple herbivore guilds in a grassland system

  Humans are increasing the scale and frequency of many natural disturbances, as well as adding novel disturbances to ecosystems. This thesis uses the arthropod community as a metric to examine the multi-trophic ...

  Citation × Citation Citation Abstract Copy Title: Vertebrates, arthropods, and invasive plants : an investigation of the top-down and bottom-up interactions of multiple herbivore guilds in a grassland system Author: Farrell, Kelly Anne Humans are increasing the scale and frequency of many natural disturbances, as well as adding novel disturbances to ecosystems. This thesis uses the arthropod community as a metric to examine the multi-trophic responses to disturbances in California grasslands. Chapter 2 explores how the long-term exclusion of native vertebrate herbivores has impacted arthropod community and trophic structure at Hastings Natural History Reserve. Chapter 3 investigates the impacts of grazing and invasive plants on the arthropod community in a manipulative plant provenance x grazing experiment that had been in place for two years at the Sierra Foothills Research and Extension Center. Few long-term studies have explored the interactions between vertebrate herbivore guilds and the arthropod community. We studied the long-term impact on arthropod community structure and composition of removing vertebrate herbivores from a California oak savannah. We used paired plots to sample arthropods and plant communities inside and outside 11 long-term vertebrate exclosures. We found that arthropods respond to vertebrate access mainly via plant compositional shifts, but that different groups of vertebrates cause changes via different pathways. Large herbivores, including deer, caused a shift from native perennial to exotic annual plants which increased plant nutritional content and supported more herbivore and detritivore arthropods. Burrowing vertebrates such as gophers reduced the predatory arthropod community by reducing vegetation structure, releasing other arthropod groups and resulting in an overall increase in arthropod abundance. These results highlight that alterations to different parts of the vertebrate community can have qualitatively different effects on arthropod community structure. The invasion and spread of non-native plants and the prevalence of livestock grazing are two human-induced disturbances that can have widespread ecosystem impacts. We used a manipulative study to examine how the replacement of native perennial grasses by exotic annual grasses and the introduction of heavy cattle grazing impact arthropod community structure. Arthropod richness, diversity, and abundance did not vary predictably between native perennial and exotic annual grass communities, though arthropods responded to plant community characteristics. In the presence of grazing, arthropod biovolume increased in annual grass treatments, which could trigger a positive-feedback cycle with vector-transmitted plant pathogens to further increase the prevalence of non-native annual grasses. Arthropod community was strongly impacted by cattle grazing, which decreased the biovolume of predatory arthropods, causing a top-down increase in herbivorous arthropod biovolume. Grazing thus impacts plant composition both through the direct removal of biomass and increased plant species evenness, and through arthropod-mediated impacts. Together, these studies show that human alterations of different vertebrate guilds can impact the trophic structure of the arthropod community. Because arthropods mediate a number of ecosystem services, disturbances that alter arthropod assemblages can have far-reaching ecosystem impacts. By exploring the mechanisms by which manipulations of the vertebrate guild alter arthropod community, this thesis demonstrates the importance of horizontal and vertical diversity in multi-trophic interactions. Title: Vertebrates, arthropods, and invasive plants : an investigation of the top-down and bottom-up interactions of multiple herbivore guilds in a grassland system Author: Farrell, Kelly Anne Humans are increasing the scale and frequency of many natural disturbances, as well as adding novel disturbances to ecosystems. This thesis uses the arthropod community as a metric to examine the multi-trophic responses to disturbances in California grasslands. Chapter 2 explores how the long-term exclusion of native vertebrate herbivores has impacted arthropod community and trophic structure at Hastings Natural History Reserve. Chapter 3 investigates the impacts of grazing and invasive plants on the arthropod community in a manipulative plant provenance x grazing experiment that had been in place for two years at the Sierra Foothills Research and Extension Center. Few long-term studies have explored the interactions between vertebrate herbivore guilds and the arthropod community. We studied the long-term impact on arthropod community structure and composition of removing vertebrate herbivores from a California oak savannah. We used paired plots to sample arthropods and plant communities inside and outside 11 long-term vertebrate exclosures. We found that arthropods respond to vertebrate access mainly via plant compositional shifts, but that different groups of vertebrates cause changes via different pathways. Large herbivores, including deer, caused a shift from native perennial to exotic annual plants which increased plant nutritional content and supported more herbivore and detritivore arthropods. Burrowing vertebrates such as gophers reduced the predatory arthropod community by reducing vegetation structure, releasing other arthropod groups and resulting in an overall increase in arthropod abundance. These results highlight that alterations to different parts of the vertebrate community can have qualitatively different effects on arthropod community structure. The invasion and spread of non-native plants and the prevalence of livestock grazing are two human-induced disturbances that can have widespread ecosystem impacts. We used a manipulative study to examine how the replacement of native perennial grasses by exotic annual grasses and the introduction of heavy cattle grazing impact arthropod community structure. Arthropod richness, diversity, and abundance did not vary predictably between native perennial and exotic annual grass communities, though arthropods responded to plant community characteristics. In the presence of grazing, arthropod biovolume increased in annual grass treatments, which could trigger a positive-feedback cycle with vector-transmitted plant pathogens to further increase the prevalence of non-native annual grasses. Arthropod community was strongly impacted by cattle grazing, which decreased the biovolume of predatory arthropods, causing a top-down increase in herbivorous arthropod biovolume. Grazing thus impacts plant composition both through the direct removal of biomass and increased plant species evenness, and through arthropod-mediated impacts. Together, these studies show that human alterations of different vertebrate guilds can impact the trophic structure of the arthropod community. Because arthropods mediate a number of ecosystem services, disturbances that alter arthropod assemblages can have far-reaching ecosystem impacts. By exploring the mechanisms by which manipulations of the vertebrate guild alter arthropod community, this thesis demonstrates the importance of horizontal and vertical diversity in multi-trophic interactions. Close

• 94. [Article] Ecology of the northern subpopulation of northern anchovy (Engraulis mordax) in the California Current large marine ecosystem

  Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, ...

  Citation × Citation Citation Abstract Copy Title: Ecology of the northern subpopulation of northern anchovy (Engraulis mordax) in the California Current large marine ecosystem Author: Litz, Marisa N. C. Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, or population fluctuations relative to ocean conditions in the eastern boundary upwelling system off the U.S. West Coast. This thesis includes three primary studies of northern anchovy in the CCLME off Oregon and Washington using data collected during four National Marine Fisheries Service (NMFS) surveys (1977-2006): inter- and intra-annual variation in anchovy distribution and its relationship to oceanography, growth rates of larval and juvenile anchovy that indicate the timing of major spawning events and changes in mortality rates, and analysis of whole lipids and fatty acid profiles to determine food sources in years of contrasting oceanographic conditions. First, I quantified the relationship between northern anchovy abundance with environmental variables at two spatial and temporal scales: 1) mesoscale, including sea surface temperature (SST), salinity (SSS), density (SSD), chlorophyll a, distance from shore, and depth; and 2) macroscale, including Pacific Decadal Oscillation Index, Multivariate El Niño Southern Oscillation Index, timing of the Spring Transition, and abundance of cold-water zooplankton. Anchovy densities increased significantly from 1999-2004, and decreased significantly from 2005-2006. SST and proximity to shore were the most consistent parameters explaining anchovy distribution. Year-class strength was highly correlated with, and presumably driven by, the abundance of cold-water copepods. Second, I characterized recruitment for northern anchovy by conducting microstructure analysis of saggital otoliths from late larval and juvenile life history phases collected in September 2006. I identified a protracted spawning period for northern anchovy ranging from June-August 2006. Juveniles that were spawned and hatched early in the summer 2006 had higher growth rates, but smaller back-calculated sizes-at-age during the larval phase, when compared to congeners spawned later that summer. Finally, I determined total lipid content and fatty acid signatures of northern anchovy and three other forage fish species during two contrasting periods of oceanographic conditions (summers of 2005 and 2006): Pacific sardine (Sardinops sagax), Pacific herring (Clupea harengus pallasii), and whitebait smelt (Allosmerus elongatus). Forage fish lipid levels were lowest in 2005 and increased in 2006. Fatty acid biomarkers in 2005 indicated that the food web was based mainly on dinoflagellates, corroborating observations of delayed coastal upwelling and low primary productivity in the CCLME. In 2006, fatty acids reflected higher levels of diatom feeding and zooplankton carnivory. The results of these studies confirm that in the CCLME, northern anchovy are sensitive to even small environmental perturbations, which is important because this work provides metrics for evaluating climate-mediated, bottom-up ecological processes affecting anchovy survival. Title: Ecology of the northern subpopulation of northern anchovy (Engraulis mordax) in the California Current large marine ecosystem Author: Litz, Marisa N. C. Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, or population fluctuations relative to ocean conditions in the eastern boundary upwelling system off the U.S. West Coast. This thesis includes three primary studies of northern anchovy in the CCLME off Oregon and Washington using data collected during four National Marine Fisheries Service (NMFS) surveys (1977-2006): inter- and intra-annual variation in anchovy distribution and its relationship to oceanography, growth rates of larval and juvenile anchovy that indicate the timing of major spawning events and changes in mortality rates, and analysis of whole lipids and fatty acid profiles to determine food sources in years of contrasting oceanographic conditions. First, I quantified the relationship between northern anchovy abundance with environmental variables at two spatial and temporal scales: 1) mesoscale, including sea surface temperature (SST), salinity (SSS), density (SSD), chlorophyll a, distance from shore, and depth; and 2) macroscale, including Pacific Decadal Oscillation Index, Multivariate El Niño Southern Oscillation Index, timing of the Spring Transition, and abundance of cold-water zooplankton. Anchovy densities increased significantly from 1999-2004, and decreased significantly from 2005-2006. SST and proximity to shore were the most consistent parameters explaining anchovy distribution. Year-class strength was highly correlated with, and presumably driven by, the abundance of cold-water copepods. Second, I characterized recruitment for northern anchovy by conducting microstructure analysis of saggital otoliths from late larval and juvenile life history phases collected in September 2006. I identified a protracted spawning period for northern anchovy ranging from June-August 2006. Juveniles that were spawned and hatched early in the summer 2006 had higher growth rates, but smaller back-calculated sizes-at-age during the larval phase, when compared to congeners spawned later that summer. Finally, I determined total lipid content and fatty acid signatures of northern anchovy and three other forage fish species during two contrasting periods of oceanographic conditions (summers of 2005 and 2006): Pacific sardine (Sardinops sagax), Pacific herring (Clupea harengus pallasii), and whitebait smelt (Allosmerus elongatus). Forage fish lipid levels were lowest in 2005 and increased in 2006. Fatty acid biomarkers in 2005 indicated that the food web was based mainly on dinoflagellates, corroborating observations of delayed coastal upwelling and low primary productivity in the CCLME. In 2006, fatty acids reflected higher levels of diatom feeding and zooplankton carnivory. The results of these studies confirm that in the CCLME, northern anchovy are sensitive to even small environmental perturbations, which is important because this work provides metrics for evaluating climate-mediated, bottom-up ecological processes affecting anchovy survival. Close

• 95. [Article] Final report: Predicting field establishment rates from standardized plant traits - Year two of: Restoring prairies: A synthesis of studies on vegetation and invasive species in support of effective management

  Willamette Valley wetland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species (Wilson et al. 1993, Noss et al. 1995, USFWS 2000, ...

  Citation × Citation Citation Abstract Copy Title: Final report: Predicting field establishment rates from standardized plant traits - Year two of: Restoring prairies: A synthesis of studies on vegetation and invasive species in support of effective management Author: Wilson, Mark V., Roberts, Rachel E., Clark, Deborah Louise, 1950- Willamette Valley wetland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species (Wilson et al. 1993, Noss et al. 1995, USFWS 2000, Schultz et al. 2003). A rigorous program of ecosystem restoration can protect and enhance wetland plants, animals, and services (Pywell and Putwain 1996). The restoration projects of the West Eugene Wetlands Program (WEWP) comprise one of the few large-scale and long-term integrated restoration programs in the world. Successful ecosystem restoration requires establishing and maintaining native plants. In turn, plant establishment hinges on having suitable environmental conditions, using species with adequate germination and growth rates, and reducing competitive pressure from non-native plants (Figure 1). In year one of this project, we synthesized the wealth of plant establishment data during wetland restoration in the West Eugene Wetlands Program (Wilson 2004). In year two, our objectives were to expand on these results in several important ways: • Generalize these results through the investigation of plant traits (Table 1) that consistently correspond to the patterns of establishment and vigor (Figure 1). • Systematically compile the results into a trait database. This database includes findings from similar ecosystems, both in the Willamette Valley and elsewhere. • Testing the effect of habitat variation on the relationship between traits and seedling establishment patterns. Our goal is to predict key aspects of prairie restoration performance, in this case establishment rates, based on species traits and habitat. These predictions can then be applied as management recommendations, such as which species to sow to maximize native plant abundance at a given site, even if the species have not been field tested. The two components of our project–plant traits and the database–are crucial to this goal. • Without the generalization that traits allow, understanding of wetland restoration increases slowly and expensively, one case study at a time. • The organization of the database will increase the power and efficiency of revealing the relationships between plant traits and plant performance. Perhaps even more important is the role of the database in developing a Web-based expert system for managers wishing to plan wetland restorations. Title: Final report: Predicting field establishment rates from standardized plant traits - Year two of: Restoring prairies: A synthesis of studies on vegetation and invasive species in support of effective management Author: Wilson, Mark V., Roberts, Rachel E., Clark, Deborah Louise, 1950- Willamette Valley wetland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species (Wilson et al. 1993, Noss et al. 1995, USFWS 2000, Schultz et al. 2003). A rigorous program of ecosystem restoration can protect and enhance wetland plants, animals, and services (Pywell and Putwain 1996). The restoration projects of the West Eugene Wetlands Program (WEWP) comprise one of the few large-scale and long-term integrated restoration programs in the world. Successful ecosystem restoration requires establishing and maintaining native plants. In turn, plant establishment hinges on having suitable environmental conditions, using species with adequate germination and growth rates, and reducing competitive pressure from non-native plants (Figure 1). In year one of this project, we synthesized the wealth of plant establishment data during wetland restoration in the West Eugene Wetlands Program (Wilson 2004). In year two, our objectives were to expand on these results in several important ways: • Generalize these results through the investigation of plant traits (Table 1) that consistently correspond to the patterns of establishment and vigor (Figure 1). • Systematically compile the results into a trait database. This database includes findings from similar ecosystems, both in the Willamette Valley and elsewhere. • Testing the effect of habitat variation on the relationship between traits and seedling establishment patterns. Our goal is to predict key aspects of prairie restoration performance, in this case establishment rates, based on species traits and habitat. These predictions can then be applied as management recommendations, such as which species to sow to maximize native plant abundance at a given site, even if the species have not been field tested. The two components of our project–plant traits and the database–are crucial to this goal. • Without the generalization that traits allow, understanding of wetland restoration increases slowly and expensively, one case study at a time. • The organization of the database will increase the power and efficiency of revealing the relationships between plant traits and plant performance. Perhaps even more important is the role of the database in developing a Web-based expert system for managers wishing to plan wetland restorations. Close

• 96. [Article] Review of Status and Opportunities in Farmed Fish using an Innovative Real Time Fish Market Information System

  Abstract Only This is part of the IIFET Special Session on Markets and Value Chains for Small Aquaculture & Fisheries Enterprises with a Focus on Gender that took place on 17 July 2012 in Dar Es Salaam, ...

  Citation × Citation Citation Abstract Copy Title: Review of Status and Opportunities in Farmed Fish using an Innovative Real Time Fish Market Information System Author: Ngugi, Charles, Quagrainie, Kwamena, Amadiva, Judith, Manyala, Julius Abstract Only This is part of the IIFET Special Session on Markets and Value Chains for Small Aquaculture & Fisheries Enterprises with a Focus on Gender that took place on 17 July 2012 in Dar Es Salaam, Tanzania in conjunction with 16th IIFET Conference. The complete proceedings of this special session are available (http://aquafishcrsp.oregonstate.edu/Documents/Uploads/FileManager/IIFET%202012%20CRSP%20Session%20Proceedings%20Final_small.pdf) through the Aquaculture & Fisheries Collaborative Research Support Program gender web site, (http://aquafishcrsp.oregonstate.edu/Gender/). Title: Review of Status and Opportunities in Farmed Fish using an Innovative Real Time Fish Market Information System Author: Ngugi, Charles, Quagrainie, Kwamena, Amadiva, Judith, Manyala, Julius Abstract Only This is part of the IIFET Special Session on Markets and Value Chains for Small Aquaculture & Fisheries Enterprises with a Focus on Gender that took place on 17 July 2012 in Dar Es Salaam, Tanzania in conjunction with 16th IIFET Conference. The complete proceedings of this special session are available (http://aquafishcrsp.oregonstate.edu/Documents/Uploads/FileManager/IIFET%202012%20CRSP%20Session%20Proceedings%20Final_small.pdf) through the Aquaculture & Fisheries Collaborative Research Support Program gender web site, (http://aquafishcrsp.oregonstate.edu/Gender/). Close

• 97. [Article] Lichen Functional Trait Variation Along an East-West Climatic Gradient in Oregon and Among Habitats in Katmai National Park, Alaska

  Functional traits of vascular plants have been an important component of ecological studies for a number of years; however, in more recent times vascular plant ecologists have begun to formalize a set ...

  Citation × Citation Citation Abstract Copy Title: Lichen Functional Trait Variation Along an East-West Climatic Gradient in Oregon and Among Habitats in Katmai National Park, Alaska Author: Spickerman, Kaleigh Functional traits of vascular plants have been an important component of ecological studies for a number of years; however, in more recent times vascular plant ecologists have begun to formalize a set of key traits and universal system of trait measurement. Many recent studies hypothesize global generality of trait patterns, which would allow for comparison among ecosystems and biomes and provide a foundation for general rules and theories, the so-called “Holy Grail” of ecology. However, the majority of these studies focus on functional trait patterns of vascular plants, with a minority examining the patterns of cryptograms such as lichens. Lichens are an important component of many ecosystems due to their contributions to biodiversity and their key ecosystem services, such as contributions to mineral and hydrological cycles and ecosystem food webs. Lichens are also of special interest because of their reliance on atmospheric deposition for nutrients and water, which makes them particularly sensitive to air pollution. Therefore, they are often used as bioindicators of air pollution, climate change, and general ecosystem health. This thesis examines the functional trait patterns of lichens in two contrasting regions with fundamentally different kinds of data. To better understand the patterns of lichen functional traits, we examined reproductive, morphological, and chemical trait variation along precipitation and temperature gradients in Oregon. Specifically, we measured traits of 102 macrolichen species collected from 166 USDA Forest Service program for Forest Inventory and Analysis (FIA) plots. These plots were located in a more-or-less continuous swath across Oregon between 43°W and 45°W. Plots were grouped into seven regions (the Oregon Coast, Coast Range, Willamette Valley, Western Cascades, High Cascades, Eastern Cascades, and Eastern Oregon). Using multivariate analysis techniques we found strong linear and nonlinear trait patterns along precipitation and temperature gradients, and were able to characterize the seven main regions of Oregon by the relative abundance of lichen traits. The literature on what lichen traits are most common in which habitats is sparse and anecdotal; understanding trait-habitat patterns could have management implications due to lichen importance as bioindicators and animal forage. Understanding how key traits are distributed among habitats could provide insight into potential air pollution impacts on certain habitats, animal movement among habitats, etc. To examine trait-habitat patterns, we measured the reproductive, morphological, and chemical traits of 429 lichen species collected haphazardly (without a formal sampling framework) from ten distinct habitats within Katmai National Park in southwest Alaska as part of a taxonomic inventory. Using multivariate analysis techniques we grouped habitats based on the expression of lichen traits and described the relative abundance of each trait in different habitats. The second goal of this study was to examine the potential usefulness of herbarium collections in ecological studies of this type. Herbarium specimens are a large potential resource that is generally unused in ecological studies due to concerns over potential bias and noise introduced by variation in collection methods. However, recent work has suggested that herbarium specimens may yield more useful results than previously thought and could be a valid resource for ecological studies. The data for our study were collected in a haphazard manner for a floristic inventory, similar to the collection methods used for many herbarium specimens. The patterns that we observed indicates that herbarium specimens may be a good resource for future research. Title: Lichen Functional Trait Variation Along an East-West Climatic Gradient in Oregon and Among Habitats in Katmai National Park, Alaska Author: Spickerman, Kaleigh Functional traits of vascular plants have been an important component of ecological studies for a number of years; however, in more recent times vascular plant ecologists have begun to formalize a set of key traits and universal system of trait measurement. Many recent studies hypothesize global generality of trait patterns, which would allow for comparison among ecosystems and biomes and provide a foundation for general rules and theories, the so-called “Holy Grail” of ecology. However, the majority of these studies focus on functional trait patterns of vascular plants, with a minority examining the patterns of cryptograms such as lichens. Lichens are an important component of many ecosystems due to their contributions to biodiversity and their key ecosystem services, such as contributions to mineral and hydrological cycles and ecosystem food webs. Lichens are also of special interest because of their reliance on atmospheric deposition for nutrients and water, which makes them particularly sensitive to air pollution. Therefore, they are often used as bioindicators of air pollution, climate change, and general ecosystem health. This thesis examines the functional trait patterns of lichens in two contrasting regions with fundamentally different kinds of data. To better understand the patterns of lichen functional traits, we examined reproductive, morphological, and chemical trait variation along precipitation and temperature gradients in Oregon. Specifically, we measured traits of 102 macrolichen species collected from 166 USDA Forest Service program for Forest Inventory and Analysis (FIA) plots. These plots were located in a more-or-less continuous swath across Oregon between 43°W and 45°W. Plots were grouped into seven regions (the Oregon Coast, Coast Range, Willamette Valley, Western Cascades, High Cascades, Eastern Cascades, and Eastern Oregon). Using multivariate analysis techniques we found strong linear and nonlinear trait patterns along precipitation and temperature gradients, and were able to characterize the seven main regions of Oregon by the relative abundance of lichen traits. The literature on what lichen traits are most common in which habitats is sparse and anecdotal; understanding trait-habitat patterns could have management implications due to lichen importance as bioindicators and animal forage. Understanding how key traits are distributed among habitats could provide insight into potential air pollution impacts on certain habitats, animal movement among habitats, etc. To examine trait-habitat patterns, we measured the reproductive, morphological, and chemical traits of 429 lichen species collected haphazardly (without a formal sampling framework) from ten distinct habitats within Katmai National Park in southwest Alaska as part of a taxonomic inventory. Using multivariate analysis techniques we grouped habitats based on the expression of lichen traits and described the relative abundance of each trait in different habitats. The second goal of this study was to examine the potential usefulness of herbarium collections in ecological studies of this type. Herbarium specimens are a large potential resource that is generally unused in ecological studies due to concerns over potential bias and noise introduced by variation in collection methods. However, recent work has suggested that herbarium specimens may yield more useful results than previously thought and could be a valid resource for ecological studies. The data for our study were collected in a haphazard manner for a floristic inventory, similar to the collection methods used for many herbarium specimens. The patterns that we observed indicates that herbarium specimens may be a good resource for future research. Close

• 98. [Article] Forestry

  Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2011. All rights reserved.

  Citation × Citation Citation Abstract Copy Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2011. All rights reserved. Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2011. All rights reserved. Close

• 99. [Article] Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica

  Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, ...

  Citation × Citation Citation Abstract Copy Title: Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica Author: Volpe, Noelia L. Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, may also negatively affect biodiversity for those species that exhibit behavioral responses to changes in habitat configuration. Such behavioral changes include movement, which is influenced by subdividing and isolating habitats through which animals prefer to travel. Ecosystem services that depend on the ability of animals to move through the landscape could be affected by changes in habitat configuration. Pollination is one such process because access of pollinators to flowers is often the key determinant of plant reproductive success. Yet, relatively little is known about how forest fragmentation may influence the flow of pollen carried by forest-dwelling pollinators, such as hummingbirds. I evaluate how changes in the distribution of pollinators produced by habitat fragmentation in southern Costa Rica affects a pollination web occupied by a generalist tropical pollinator, the green hermit hummingbird (Phaethornis guy). I used radio-telemetry to measure patterns of space use by green hermits living in forested areas with different levels of fragmentation. I first characterize patterns of space use by green hermits at three scales: point, path and home range. I found that green hermits have marked preference for locations in forested areas with high density of Heliconia plants and canopy cover; prefer paths close to streams that minimize crossing large stretches of non-forested matrix; and establish their home ranges in areas with high forest amount. In addition, home range area was negatively related to the amount of forest within it and positively related to fragmentation per se. Average resource density within the home range appeared to be unrelated to the area covered by the green hermits. My observations indicate that while the presence of green hermits in an area is mainly determined by the amount of forest available, the way they move through a landscape will be strongly affected by habitat configuration. In this context, pollen transfer by green hermits will be limited by the presence of open, non-forested areas owing to matrix avoidance. In landscapes with small discontinuous patches, the total area covered by an individual green hermit is likely to be small so I hypothesize that the genetic variability of pollen it transports may be diminished. I also assess the effectiveness of a tool commonly used to study the effect of habitat fragmentation on animal movement: translocation experiments. Such experiments are purported to have important advantages of being time efficient and standardizing across individuals the ‘motivation’ to move. Yet, we lack tests of whether movement behavior of translocated birds reflects natural behavior of unmanipulated birds. I compared the routine movement behavior of green hermits to that of experimentally translocated individuals. Behaviors documented during translocation experiments reflected those observed during routine movements. Both translocated and non-translocated birds showed similar levels of preference for mature tropical forest at the point level and avoided moving across non-forested matrix while selecting streams as movement corridors at the path level. Movement rates (distance covered per unit time) were generally higher during translocation experiments. However, the negative influence of forest cover on movement rates was proportionately similar in translocation and routine movement treatments. My results show that movement behavior of birds during translocation experiments is similar to natural movement behavior of birds. Therefore, translocation experiments may be reliable tools to address effects of landscape structure on animal movement. Title: Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica Author: Volpe, Noelia L. Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, may also negatively affect biodiversity for those species that exhibit behavioral responses to changes in habitat configuration. Such behavioral changes include movement, which is influenced by subdividing and isolating habitats through which animals prefer to travel. Ecosystem services that depend on the ability of animals to move through the landscape could be affected by changes in habitat configuration. Pollination is one such process because access of pollinators to flowers is often the key determinant of plant reproductive success. Yet, relatively little is known about how forest fragmentation may influence the flow of pollen carried by forest-dwelling pollinators, such as hummingbirds. I evaluate how changes in the distribution of pollinators produced by habitat fragmentation in southern Costa Rica affects a pollination web occupied by a generalist tropical pollinator, the green hermit hummingbird (Phaethornis guy). I used radio-telemetry to measure patterns of space use by green hermits living in forested areas with different levels of fragmentation. I first characterize patterns of space use by green hermits at three scales: point, path and home range. I found that green hermits have marked preference for locations in forested areas with high density of Heliconia plants and canopy cover; prefer paths close to streams that minimize crossing large stretches of non-forested matrix; and establish their home ranges in areas with high forest amount. In addition, home range area was negatively related to the amount of forest within it and positively related to fragmentation per se. Average resource density within the home range appeared to be unrelated to the area covered by the green hermits. My observations indicate that while the presence of green hermits in an area is mainly determined by the amount of forest available, the way they move through a landscape will be strongly affected by habitat configuration. In this context, pollen transfer by green hermits will be limited by the presence of open, non-forested areas owing to matrix avoidance. In landscapes with small discontinuous patches, the total area covered by an individual green hermit is likely to be small so I hypothesize that the genetic variability of pollen it transports may be diminished. I also assess the effectiveness of a tool commonly used to study the effect of habitat fragmentation on animal movement: translocation experiments. Such experiments are purported to have important advantages of being time efficient and standardizing across individuals the ‘motivation’ to move. Yet, we lack tests of whether movement behavior of translocated birds reflects natural behavior of unmanipulated birds. I compared the routine movement behavior of green hermits to that of experimentally translocated individuals. Behaviors documented during translocation experiments reflected those observed during routine movements. Both translocated and non-translocated birds showed similar levels of preference for mature tropical forest at the point level and avoided moving across non-forested matrix while selecting streams as movement corridors at the path level. Movement rates (distance covered per unit time) were generally higher during translocation experiments. However, the negative influence of forest cover on movement rates was proportionately similar in translocation and routine movement treatments. My results show that movement behavior of birds during translocation experiments is similar to natural movement behavior of birds. Therefore, translocation experiments may be reliable tools to address effects of landscape structure on animal movement. Close

• 100. [Article] Forestry

  Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2013. All rights reserved.

  Citation × Citation Citation Abstract Copy Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2013. All rights reserved. Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2013. All rights reserved. Close