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• 41. [Article] Statistical foraminiferal ecology from seasonal samples, central Oregon continental shelf

  This study examined the foraminifera and the ecologic conditions of the benthic environment of the Oregon shelf and the uppermost slope (75-550 m depth) between 143°45' N and 144°40' N. Seasonal collections monitored ...

  Citation × Citation Citation Abstract Copy Title: Statistical foraminiferal ecology from seasonal samples, central Oregon continental shelf Author: Gunther, Fredrick John This study examined the foraminifera and the ecologic conditions of the benthic environment of the Oregon shelf and the uppermost slope (75-550 m depth) between 143°45' N and 144°40' N. Seasonal collections monitored the near-bottom marine environment and the sedimentary substrate at 16 stations. The foraminiferal benthic fauna was examined from eight seasonal stations and two additional stations. Use of a multiple corer provided randomly selected subsarnples of the sediment for ecologic and faunal analyses. Use of water bottles that triggered upon bottom impact provided measurements of the water as close to the bottom as 0. 6 m. Computerized data processing and statistical analyses aided the ecologic and faunal evaluations. The environmental study showed the existence of considerable variation in the hydrography of near-bottom waters, especially between summer and winter (upwelling and non-upwelling) collections at the same station. Upwelling conditions directly affect the benthic Redacted for Privacy environment. In addition, the water at any one place, at least dciring upwelling, was so well mixed that vertical stratification did not exist between 0.6 and 5.0 m off the bottom. Statistically significant sea-. sorial variations in surface sediments at the same station were not observed. The living benthic foraminiferal fauna exhibited considerable within-station variation both in species composition and in specimen size of selected species. The percent abundance of individual dominant species varied in adjacent cores (subsamples) by amounts up to 46%. Living specimens of a single species were found that were three times as large as the smallest living specimen from the same sample, yet there was no evidence of a multimodal size distribution resulting from age classes. The author suggests that the dominant species are aggregated and that the aggregations are colonies of asexually produced siblings. Lack of fit of species-frequency curves to the lognormal distribution indicated that relatively few species are fit to reproduce in a particular environment; most juvenile specimens that enter a particular environment belong to species that will not thrive there and either die or simply maintain growth with little chance of reproductive success. The existence of colonial aggregations of individuals is considered to provide the best explanation of the observed variations between adjacent samples. However, the observed variations could be due to sampling error or to substrate microheterogeneity. A possible natural community of 15 dominant species has been determined for those species that form a consistent part of each other's biologic environment. The community crossed the depth and substrate boundaries upon which the stations were selected and appeared to be a general community for the Oregon outer shelf. The limits of the community appear to be determined mostly by water depth, with approximate boundaries at 75-100 m and somewhere between 200-500 m. Regression analyses to determine the ecologic control on the foraminiferal fauna did not indicate a close correspondence between faunal parameters and environmental variables. Regression analyses to determine the ecologic control on mdividual species indicated that most species depended upon a set of two to four environmental variables rather than upon one single limiting factor. The set for each species was different. Temperature. phosphate concentration and oxygen concentrations were common hydrographic members of sets; percent silt, percent sand, percent clay, organic carbon content and organic nitrogen were common sedimentary members of sets. Title: Statistical foraminiferal ecology from seasonal samples, central Oregon continental shelf Author: Gunther, Fredrick John This study examined the foraminifera and the ecologic conditions of the benthic environment of the Oregon shelf and the uppermost slope (75-550 m depth) between 143°45' N and 144°40' N. Seasonal collections monitored the near-bottom marine environment and the sedimentary substrate at 16 stations. The foraminiferal benthic fauna was examined from eight seasonal stations and two additional stations. Use of a multiple corer provided randomly selected subsarnples of the sediment for ecologic and faunal analyses. Use of water bottles that triggered upon bottom impact provided measurements of the water as close to the bottom as 0. 6 m. Computerized data processing and statistical analyses aided the ecologic and faunal evaluations. The environmental study showed the existence of considerable variation in the hydrography of near-bottom waters, especially between summer and winter (upwelling and non-upwelling) collections at the same station. Upwelling conditions directly affect the benthic Redacted for Privacy environment. In addition, the water at any one place, at least dciring upwelling, was so well mixed that vertical stratification did not exist between 0.6 and 5.0 m off the bottom. Statistically significant sea-. sorial variations in surface sediments at the same station were not observed. The living benthic foraminiferal fauna exhibited considerable within-station variation both in species composition and in specimen size of selected species. The percent abundance of individual dominant species varied in adjacent cores (subsamples) by amounts up to 46%. Living specimens of a single species were found that were three times as large as the smallest living specimen from the same sample, yet there was no evidence of a multimodal size distribution resulting from age classes. The author suggests that the dominant species are aggregated and that the aggregations are colonies of asexually produced siblings. Lack of fit of species-frequency curves to the lognormal distribution indicated that relatively few species are fit to reproduce in a particular environment; most juvenile specimens that enter a particular environment belong to species that will not thrive there and either die or simply maintain growth with little chance of reproductive success. The existence of colonial aggregations of individuals is considered to provide the best explanation of the observed variations between adjacent samples. However, the observed variations could be due to sampling error or to substrate microheterogeneity. A possible natural community of 15 dominant species has been determined for those species that form a consistent part of each other's biologic environment. The community crossed the depth and substrate boundaries upon which the stations were selected and appeared to be a general community for the Oregon outer shelf. The limits of the community appear to be determined mostly by water depth, with approximate boundaries at 75-100 m and somewhere between 200-500 m. Regression analyses to determine the ecologic control on the foraminiferal fauna did not indicate a close correspondence between faunal parameters and environmental variables. Regression analyses to determine the ecologic control on mdividual species indicated that most species depended upon a set of two to four environmental variables rather than upon one single limiting factor. The set for each species was different. Temperature. phosphate concentration and oxygen concentrations were common hydrographic members of sets; percent silt, percent sand, percent clay, organic carbon content and organic nitrogen were common sedimentary members of sets. Close

• 42. [Article] Realized and potential climate responses of lichen and bryophyte communities in a national forest inventory

  Climate and terrestrial vegetation have had mutual feedbacks for nearly five hundred million years, yet both are now departing from recent historical norms, with uncertain implications for forest ecosystems. ...

  Citation × Citation Citation Abstract Copy Title: Realized and potential climate responses of lichen and bryophyte communities in a national forest inventory Author: Smith, Robert J. Climate and terrestrial vegetation have had mutual feedbacks for nearly five hundred million years, yet both are now departing from recent historical norms, with uncertain implications for forest ecosystems. This dissertation outlines the current and potential future climate responses of lichen and bryophyte communities in the United States as part of a national forest inventory. The first task was to identify influences on carbon and nitrogen storage of moss and lichen “ground layers” in subarctic interior Alaska. Nutrient stores were more sensitive to local vegetation and topography than regional macroclimate. Nutrients and biomass were greatest among apparently less disturbed stands. This suggests that climatic changes could diminish ground layer nutrient storage indirectly if they promote intensifying wildfire regimes or expansions of competitive vascular vegetation. Turning to focus on species diversity, the next task was to quantify the strength of relationship between epiphytic lichen community composition and macroclimate across the 4,000 km-long swath of the U.S. Pacific coastal states. The strongest fitting lichen response gradients involved precipitation, temperature, and a heat-moisture index. Lichen indicator species (diagnostic of ten defined climate zones) emerged as useful monitoring tools because their abundance changes could signal shifting climate zone boundaries. After establishing key present-day climatic relationships, the next task was to pinpoint nationwide locations where epiphytic lichen communities will be most vulnerable to species losses under current and future warming scenarios. Novel niche-based metrics revealed greatest vulnerability among supposedly “warm-adapted” communities in southern/lowland locations, contrary to usual assumptions centering on cooler northern/montane habitats. Vulnerability analyses can steer conservation and monitoring attention to specific locations where warming is most expected to affect ecological communities. The final task, to anticipate how warming will impact individual lichen performance, was addressed by quantifying how experimental climate treatments (whole-ecosystem warming and CO2 additions) affected growth of the boreal epiphytic lichen species Evernia mesomorpha. Over just one year, incremental warming and concurrent drying caused progressive growth declines and biomass losses among individual transplants. Such warming-induced biomass losses of epiphytic lichens could precede local population extinctions and regional range contractions. Overall, this dissertation weaves together multiple lines of evidence from nutrient, diversity and growth responses to indicate the ecological effects of climate and climatic changes on vegetation in a national forest inventory context. This work suggests a pathway for integrating lichen and bryophyte responses into nationwide climate monitoring to address emergent interactions between humans, vegetation, and the global climate commons. Title: Realized and potential climate responses of lichen and bryophyte communities in a national forest inventory Author: Smith, Robert J. Climate and terrestrial vegetation have had mutual feedbacks for nearly five hundred million years, yet both are now departing from recent historical norms, with uncertain implications for forest ecosystems. This dissertation outlines the current and potential future climate responses of lichen and bryophyte communities in the United States as part of a national forest inventory. The first task was to identify influences on carbon and nitrogen storage of moss and lichen “ground layers” in subarctic interior Alaska. Nutrient stores were more sensitive to local vegetation and topography than regional macroclimate. Nutrients and biomass were greatest among apparently less disturbed stands. This suggests that climatic changes could diminish ground layer nutrient storage indirectly if they promote intensifying wildfire regimes or expansions of competitive vascular vegetation. Turning to focus on species diversity, the next task was to quantify the strength of relationship between epiphytic lichen community composition and macroclimate across the 4,000 km-long swath of the U.S. Pacific coastal states. The strongest fitting lichen response gradients involved precipitation, temperature, and a heat-moisture index. Lichen indicator species (diagnostic of ten defined climate zones) emerged as useful monitoring tools because their abundance changes could signal shifting climate zone boundaries. After establishing key present-day climatic relationships, the next task was to pinpoint nationwide locations where epiphytic lichen communities will be most vulnerable to species losses under current and future warming scenarios. Novel niche-based metrics revealed greatest vulnerability among supposedly “warm-adapted” communities in southern/lowland locations, contrary to usual assumptions centering on cooler northern/montane habitats. Vulnerability analyses can steer conservation and monitoring attention to specific locations where warming is most expected to affect ecological communities. The final task, to anticipate how warming will impact individual lichen performance, was addressed by quantifying how experimental climate treatments (whole-ecosystem warming and CO2 additions) affected growth of the boreal epiphytic lichen species Evernia mesomorpha. Over just one year, incremental warming and concurrent drying caused progressive growth declines and biomass losses among individual transplants. Such warming-induced biomass losses of epiphytic lichens could precede local population extinctions and regional range contractions. Overall, this dissertation weaves together multiple lines of evidence from nutrient, diversity and growth responses to indicate the ecological effects of climate and climatic changes on vegetation in a national forest inventory context. This work suggests a pathway for integrating lichen and bryophyte responses into nationwide climate monitoring to address emergent interactions between humans, vegetation, and the global climate commons. Close

• 43. [Article] Spatial and Temporal Variability of Contaminants Within Estuarine Sediments and Native Olympia Oysters: A Contrast Between a Developed and an Undeveloped Estuary

  Chemical contaminants can be introduced into estuarine and marine ecosystems from a variety of sources including wastewater, agriculture and forestry practices, point and non-point discharges, runoff from ...

  Citation × Citation Citation Abstract Copy Title: Spatial and Temporal Variability of Contaminants Within Estuarine Sediments and Native Olympia Oysters: A Contrast Between a Developed and an Undeveloped Estuary Author: Granek, Elise F., Conn, Katherine E., Nilsen, Elena B., Pillsbury, Lori, Strecker, Angela L., Rumrill, Steven S., Fish, William Year: 2016 Chemical contaminants can be introduced into estuarine and marine ecosystems from a variety of sources including wastewater, agriculture and forestry practices, point and non-point discharges, runoff from industrial, municipal, and urban lands, accidental spills, and atmospheric deposition. The diversity of potential sources contributes to the likelihood of contaminated marine waters and sediments and increases the probability of uptake by marine organisms. Despite widespread recognition of direct and indirect pathways for contaminant deposition and organismal exposure in coastal systems, spatial and temporal variability in contaminant composition, deposition, and uptake patterns are still poorly known. We investigated these patterns for a suite of persistent legacy contaminants including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) and chemicals of emerging concern including pharmaceuticals within two Oregon coastal estuaries (Coos and Netarts Bays). In the more urbanized Coos Bay, native Olympia oyster (Ostrea lurida) tissue had approximately twice the number of PCB congeners at over seven times the total concentration, yet fewer PBDEs at one-tenth the concentration as compared to the more rural Netarts Bay. Different pharmaceutical suites were detected during each sampling season. Variability in contaminant types and concentrations across seasons and between species and media (organisms versus sediment) indicates the limitation of using indicator species and/or sampling annually to determine contaminant loads at a site or for specific species. The results indicate the prevalence of legacy contaminants and CECs in relatively undeveloped coastal environments highlighting the need to improve policy and management actions to reduce contaminant releases into estuarine and marine waters and to deal with legacy compounds that remain long after prohibition of use. Our results point to the need for better understanding of the ecological and human health risks of exposure to the diverse cocktail of pollutants and harmful compounds that will continue to leach from estuarine sediments over time. Title: Spatial and Temporal Variability of Contaminants Within Estuarine Sediments and Native Olympia Oysters: A Contrast Between a Developed and an Undeveloped Estuary Author: Granek, Elise F., Conn, Katherine E., Nilsen, Elena B., Pillsbury, Lori, Strecker, Angela L., Rumrill, Steven S., Fish, William Year: 2016 Chemical contaminants can be introduced into estuarine and marine ecosystems from a variety of sources including wastewater, agriculture and forestry practices, point and non-point discharges, runoff from industrial, municipal, and urban lands, accidental spills, and atmospheric deposition. The diversity of potential sources contributes to the likelihood of contaminated marine waters and sediments and increases the probability of uptake by marine organisms. Despite widespread recognition of direct and indirect pathways for contaminant deposition and organismal exposure in coastal systems, spatial and temporal variability in contaminant composition, deposition, and uptake patterns are still poorly known. We investigated these patterns for a suite of persistent legacy contaminants including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) and chemicals of emerging concern including pharmaceuticals within two Oregon coastal estuaries (Coos and Netarts Bays). In the more urbanized Coos Bay, native Olympia oyster (Ostrea lurida) tissue had approximately twice the number of PCB congeners at over seven times the total concentration, yet fewer PBDEs at one-tenth the concentration as compared to the more rural Netarts Bay. Different pharmaceutical suites were detected during each sampling season. Variability in contaminant types and concentrations across seasons and between species and media (organisms versus sediment) indicates the limitation of using indicator species and/or sampling annually to determine contaminant loads at a site or for specific species. The results indicate the prevalence of legacy contaminants and CECs in relatively undeveloped coastal environments highlighting the need to improve policy and management actions to reduce contaminant releases into estuarine and marine waters and to deal with legacy compounds that remain long after prohibition of use. Our results point to the need for better understanding of the ecological and human health risks of exposure to the diverse cocktail of pollutants and harmful compounds that will continue to leach from estuarine sediments over time. Close

• 44. [Article] Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem

  Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification ...

  Citation × Citation Citation Abstract Copy Title: Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem Author: Reese, Douglas Charles Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification of such marine, biological hotspots would be of great importance to resource managers, conservationists, and research planners, and is consequently a growing area of research. Furthermore, in order to understand how ecosystems function and persist, it is necessary to know how ecological communities are distributed. The overall goal of this study is to provide further understanding regarding the functioning of marine ecosystems in such highly variable environments and to provide information about the distribution and structure of marine communities. Sampling was conducted during June and August of 2000 and 2002 as part of the U.S. GLOBEC mesoscale surveys from Newport, Oregon in the north to Crescent City, California in the south. A geostatistical approach was used to create surfaces used in a GIS to determine the distribution of various community characteristics. Two biological hotspots were identified and determined to persist in space and time, yet differed with respect to biological and physical features and in the amount of area covered. Various community analyses, including nonmetric multidimensional scaling, indicator species analysis, and cluster analysis were used to determine various community properties associated with the hotspots and non-hotspot regions. Results indicate that nekton biological hotspots in the northern California Current persist across differing environmental and biological conditions, although upwelling-based hotspots may be more susceptible to climatic conditions than retention-based hotspots. Analyses of the distribution of the functional groups within the region indicate that the predominant biological activity is spatially nonrandom and occurs within persistent, localized areas. Analyses of species associations suggest a moderate degree of redundancy. The presence of such complementary species within functional groups may confer the stability observed within these systems. The finding that large regional areas are composed of smaller, localized hotspots where a predominant amount of biological activity is occurring, suggests that the evaluation of large marine ecosystems may lead to erroneous or misleading results if they do not consider the more persistent, localized biological hotspots. Title: Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem Author: Reese, Douglas Charles Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification of such marine, biological hotspots would be of great importance to resource managers, conservationists, and research planners, and is consequently a growing area of research. Furthermore, in order to understand how ecosystems function and persist, it is necessary to know how ecological communities are distributed. The overall goal of this study is to provide further understanding regarding the functioning of marine ecosystems in such highly variable environments and to provide information about the distribution and structure of marine communities. Sampling was conducted during June and August of 2000 and 2002 as part of the U.S. GLOBEC mesoscale surveys from Newport, Oregon in the north to Crescent City, California in the south. A geostatistical approach was used to create surfaces used in a GIS to determine the distribution of various community characteristics. Two biological hotspots were identified and determined to persist in space and time, yet differed with respect to biological and physical features and in the amount of area covered. Various community analyses, including nonmetric multidimensional scaling, indicator species analysis, and cluster analysis were used to determine various community properties associated with the hotspots and non-hotspot regions. Results indicate that nekton biological hotspots in the northern California Current persist across differing environmental and biological conditions, although upwelling-based hotspots may be more susceptible to climatic conditions than retention-based hotspots. Analyses of the distribution of the functional groups within the region indicate that the predominant biological activity is spatially nonrandom and occurs within persistent, localized areas. Analyses of species associations suggest a moderate degree of redundancy. The presence of such complementary species within functional groups may confer the stability observed within these systems. The finding that large regional areas are composed of smaller, localized hotspots where a predominant amount of biological activity is occurring, suggests that the evaluation of large marine ecosystems may lead to erroneous or misleading results if they do not consider the more persistent, localized biological hotspots. Close

• 45. [Article] Evaluating benthic macroinvertebrates as bio-indicators of freshwater habitat quality in an eastern Oregon agro-ecosystem

  The effect of anthropogenic disturbance on river systems is gaining attention, and concerns about the state of freshwater natural resources are increasing globally, as are efforts to restore habitat that ...

  Citation × Citation Citation Abstract Copy Title: Evaluating benthic macroinvertebrates as bio-indicators of freshwater habitat quality in an eastern Oregon agro-ecosystem Author: Scherr, Melissa A. The effect of anthropogenic disturbance on river systems is gaining attention, and concerns about the state of freshwater natural resources are increasing globally, as are efforts to restore habitat that has been degraded by disturbance. In rivers, non-point source pollution affects the physical characteristics of the habitat and the endemic biotic assemblages. Aquatic macroinvertebrates are numerous and exhibit graded responses to various types of disturbance in the river, and may be used as indicators of habitat conditions. In this dissertation, macroinvertebrates were examined as bioindicators in the Umatilla River in eastern Oregon. The first study is a bioassessment of the impacts of agriculture on the benthic macroinvertebrate community in adjacent streams. The results of this study show that there are physical differences in habitat associated with adjacent land use, and the macroinvertebrate communities responded to these differences with changes in taxa richness and evenness. Indicator species analysis identified thirteen taxa which were indicative of habitat conditions associated with ideal habitat used as a reference condition, degraded habitat associated with agricultural land use, and transitional habitat associated with conservation/restoration management. The second study is a laboratory study in which the effects of temperature of a common mayfly nymph, Epeorus albertae (McDunnough) (Ephemeroptera: Heptageniidae) were evaluated. The study showed that not only the developmental rate of the nymphs was affected by temperature treatment (within a range of 18°C and 28°C), but the location of accumulated body tissues over time varied by temperature, with significant difference in the type of growth observed for insects held at the highest temperature. The third study examined the response of six indicator taxa to environmental variables as predictors of abundance in a non-parametric multiplicative regression. This study found that for all taxa examined, the two best predictors of abundance in the Umatilla River were turbidity and conductivity. Increased turbidity and conductivity are common effects of intensive agriculture in streams located in agro-ecosystems, but may potentially be mitigated by vegetative buffer strips and sustainable land use practices. Long term agricultural disturbance in the landscape has been shown to have lasting effects in the ecosystem which may be further exacerbated as global climate change increases dependence on freshwater resources. Understanding anthropogenic impacts on organismal communities and natural resources is vital to establishment of effective conservation, restoration, and maintenance of a healthy ecosystem. Title: Evaluating benthic macroinvertebrates as bio-indicators of freshwater habitat quality in an eastern Oregon agro-ecosystem Author: Scherr, Melissa A. The effect of anthropogenic disturbance on river systems is gaining attention, and concerns about the state of freshwater natural resources are increasing globally, as are efforts to restore habitat that has been degraded by disturbance. In rivers, non-point source pollution affects the physical characteristics of the habitat and the endemic biotic assemblages. Aquatic macroinvertebrates are numerous and exhibit graded responses to various types of disturbance in the river, and may be used as indicators of habitat conditions. In this dissertation, macroinvertebrates were examined as bioindicators in the Umatilla River in eastern Oregon. The first study is a bioassessment of the impacts of agriculture on the benthic macroinvertebrate community in adjacent streams. The results of this study show that there are physical differences in habitat associated with adjacent land use, and the macroinvertebrate communities responded to these differences with changes in taxa richness and evenness. Indicator species analysis identified thirteen taxa which were indicative of habitat conditions associated with ideal habitat used as a reference condition, degraded habitat associated with agricultural land use, and transitional habitat associated with conservation/restoration management. The second study is a laboratory study in which the effects of temperature of a common mayfly nymph, Epeorus albertae (McDunnough) (Ephemeroptera: Heptageniidae) were evaluated. The study showed that not only the developmental rate of the nymphs was affected by temperature treatment (within a range of 18°C and 28°C), but the location of accumulated body tissues over time varied by temperature, with significant difference in the type of growth observed for insects held at the highest temperature. The third study examined the response of six indicator taxa to environmental variables as predictors of abundance in a non-parametric multiplicative regression. This study found that for all taxa examined, the two best predictors of abundance in the Umatilla River were turbidity and conductivity. Increased turbidity and conductivity are common effects of intensive agriculture in streams located in agro-ecosystems, but may potentially be mitigated by vegetative buffer strips and sustainable land use practices. Long term agricultural disturbance in the landscape has been shown to have lasting effects in the ecosystem which may be further exacerbated as global climate change increases dependence on freshwater resources. Understanding anthropogenic impacts on organismal communities and natural resources is vital to establishment of effective conservation, restoration, and maintenance of a healthy ecosystem. Close

• 46. [Article] How Much Groundwater does a Wetland Need? Setting Ecological Water Requirements for Groundwater-Dependent Ecosystems

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: How Much Groundwater does a Wetland Need? Setting Ecological Water Requirements for Groundwater-Dependent Ecosystems Author: Carroll, Trish, Congdon, Roger, Aldous, Allison, Bach, Leslie, Gurrieri, Joe Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: How Much Groundwater does a Wetland Need? Setting Ecological Water Requirements for Groundwater-Dependent Ecosystems Author: Carroll, Trish, Congdon, Roger, Aldous, Allison, Bach, Leslie, Gurrieri, Joe Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 47. [Article] Headwater stream macroinvertebrates of the H.J. Andrews Experimental Forest, Oregon

  Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects ...

  Citation × Citation Citation Abstract Copy Title: Headwater stream macroinvertebrates of the H.J. Andrews Experimental Forest, Oregon Author: Frady, Charles H. Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects of forest harvest on macroinvertebrate communities in headwater streams. This study investigated headwater stream macroinvertebrate communities in the H.J. Andrews Experimental Forest, Oregon, U.S.A and used a paired-stream study design to examine the effect of prior forest harvest on stream macroinvertebrates. Concomitantly, this study examined how macroinvertebrate life-history traits were related to stream size, substrates, discharge, or water temperature. Results from this study suggest that neither richness nor densities differed between streams flowing through young growth versus old growth forests. Despite similarities among these metrics, multivariate ordination techniques helped elucidate differences in benthic community composition between paired streams when red alder was present in riparian zones of previously harvested basins. Indicator Species Analysis of community composition and abundance revealed that no taxa were exclusively indicative of either forest type. Macroinvertebrate life-history traits among headwater streams were related to stream size, stream substrates, or stream discharge. As predicted, macroinvertebrates that ingest leaf litter (shredders) decreased proportionally with increasing stream width, while macroinvertebrates that scrape off algae and biofilms from instream substrates (scrapers) increased with increasing stream width. Differences in macroinvertebrate habit-trait groups were related to differences in stream substrates or stream discharge between very small headwater streams (< 20ha basin area) and larger headwater streams (50-100ha basin size). Seasonal variation in stream discharge also influenced macroinvertebrate communities. Patterns in adult insect emergence in these streams displayed pulses of activity that varied among streams. During summer 2003, total emergence was greatest in one high elevation stream in this study. During spring 2004, total emergence began earlier in one low elevation and one mid elevation stream, but linkages with stream water temperature were tenuous; cumulative emergence remained higher in these streams than all others through early summer 2004. Though forest harvest often has immediate effects on macroinvertebrate communities, shifts in community composition may persist long-term if regrowth of riparian vegetation includes red alder (Alnus rubra). Analyses of macroinvertebrate life-history traits provided insight regarding species adaptations to environmental conditions. Among six headwater streams within a relatively small landscape (6400ha), proportions of stream macroinvertebrate communities with specific traits differed among streams relative to variability in physical stream attributes. Title: Headwater stream macroinvertebrates of the H.J. Andrews Experimental Forest, Oregon Author: Frady, Charles H. Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects of forest harvest on macroinvertebrate communities in headwater streams. This study investigated headwater stream macroinvertebrate communities in the H.J. Andrews Experimental Forest, Oregon, U.S.A and used a paired-stream study design to examine the effect of prior forest harvest on stream macroinvertebrates. Concomitantly, this study examined how macroinvertebrate life-history traits were related to stream size, substrates, discharge, or water temperature. Results from this study suggest that neither richness nor densities differed between streams flowing through young growth versus old growth forests. Despite similarities among these metrics, multivariate ordination techniques helped elucidate differences in benthic community composition between paired streams when red alder was present in riparian zones of previously harvested basins. Indicator Species Analysis of community composition and abundance revealed that no taxa were exclusively indicative of either forest type. Macroinvertebrate life-history traits among headwater streams were related to stream size, stream substrates, or stream discharge. As predicted, macroinvertebrates that ingest leaf litter (shredders) decreased proportionally with increasing stream width, while macroinvertebrates that scrape off algae and biofilms from instream substrates (scrapers) increased with increasing stream width. Differences in macroinvertebrate habit-trait groups were related to differences in stream substrates or stream discharge between very small headwater streams (< 20ha basin area) and larger headwater streams (50-100ha basin size). Seasonal variation in stream discharge also influenced macroinvertebrate communities. Patterns in adult insect emergence in these streams displayed pulses of activity that varied among streams. During summer 2003, total emergence was greatest in one high elevation stream in this study. During spring 2004, total emergence began earlier in one low elevation and one mid elevation stream, but linkages with stream water temperature were tenuous; cumulative emergence remained higher in these streams than all others through early summer 2004. Though forest harvest often has immediate effects on macroinvertebrate communities, shifts in community composition may persist long-term if regrowth of riparian vegetation includes red alder (Alnus rubra). Analyses of macroinvertebrate life-history traits provided insight regarding species adaptations to environmental conditions. Among six headwater streams within a relatively small landscape (6400ha), proportions of stream macroinvertebrate communities with specific traits differed among streams relative to variability in physical stream attributes. Close

• 48. [Article] The effect of broadcast burning on the quality of winter forage for elk, westen Oregon

  The Roosevelt elk (Cervus elephus roosevelti) is a National Forest management indicator species on the westside of the Cascade mountains, Western Oregon. A Habitat Effectiveness model is used by State ...

  Citation × Citation Citation Abstract Copy Title: The effect of broadcast burning on the quality of winter forage for elk, westen Oregon Author: Friesen, Cheryl Ann The Roosevelt elk (Cervus elephus roosevelti) is a National Forest management indicator species on the westside of the Cascade mountains, Western Oregon. A Habitat Effectiveness model is used by State and Federal agencies to evaluate elk habitat in the region. Concerns about the model's lack of differentiation between winter and summer ranges in the analyses and assumptions that burning will increase forage quality on winter range prompted this study. I investigated the effect of broadcast burning, plant association, and time since disturbance on the quality of trailing blackberry (Rubus ulna), red huckleberry (Vaccinium parviflorum), willow (Salix spp.), vine maple (Acer circinatum), salal (Gaultheria shallon), and red elderberry (Sambucus racemosa). Crude protein, neutral detergent fiber, acid detergent fiber, acid insoluble ash, lignin, astringency, condensed tannin, and hydrolyzable tannin contents were measured. No significant effects of burning, plant association, or age were observed for crude protein, hydrolyzable tannins, or neutral detergent fiber. Crude protein varied among taxa: trailing blackberry contained 9.65%, and the other taxa ranged from 5.21-7.24%. Neutral detergent fiber was highly variable: trailing blackberry contained 30.90%, and the other taxa ranged from 52.20%-65.06%. Acid detergent fiber content ranged from 44.88%-49.49% for all taxa except trailing blackberry (17.78%). Lignin varied among taxa: trailing blackberry had the lowest content (6.37%) and salal had the highest (30.25%). Lignin content in salal was greater on recently disturbed sites. Astringency ranged from 0.0015 mg protein precipitated per mg plant tissue in vine maple to 0.6737 in trailing blackberry. Salal and willow had intermediate astringencies: elderberry, huckleberry, and vine maple had the lowest. Hydrolyzable tannins were present in all species except red elderberry. Burning and plant association effected astringency and condensed tannin content in trailing blackberry and huckleberry. Samples from burned, very dry and resource-poor sites had higher astringencies than on similar unburned units and non-resource-limiting sites. Condensed tannin contents increased with unit age in salal, huckleberry, and trailing blackberry, possibly accumulating during peak years of re-establishment after disturbance. Vine maple and red huckleberry were the only taxa with positive digestible protein levels. Digestible protein content may be higher in winter forage on less severe sites. Elk forage enhancement in winter range should be evaluated on a site-specific basis. Burning did not promote a detectable increase in quality for these forage taxa, and it decreased the quality of species sensitive to site conditions. Title: The effect of broadcast burning on the quality of winter forage for elk, westen Oregon Author: Friesen, Cheryl Ann The Roosevelt elk (Cervus elephus roosevelti) is a National Forest management indicator species on the westside of the Cascade mountains, Western Oregon. A Habitat Effectiveness model is used by State and Federal agencies to evaluate elk habitat in the region. Concerns about the model's lack of differentiation between winter and summer ranges in the analyses and assumptions that burning will increase forage quality on winter range prompted this study. I investigated the effect of broadcast burning, plant association, and time since disturbance on the quality of trailing blackberry (Rubus ulna), red huckleberry (Vaccinium parviflorum), willow (Salix spp.), vine maple (Acer circinatum), salal (Gaultheria shallon), and red elderberry (Sambucus racemosa). Crude protein, neutral detergent fiber, acid detergent fiber, acid insoluble ash, lignin, astringency, condensed tannin, and hydrolyzable tannin contents were measured. No significant effects of burning, plant association, or age were observed for crude protein, hydrolyzable tannins, or neutral detergent fiber. Crude protein varied among taxa: trailing blackberry contained 9.65%, and the other taxa ranged from 5.21-7.24%. Neutral detergent fiber was highly variable: trailing blackberry contained 30.90%, and the other taxa ranged from 52.20%-65.06%. Acid detergent fiber content ranged from 44.88%-49.49% for all taxa except trailing blackberry (17.78%). Lignin varied among taxa: trailing blackberry had the lowest content (6.37%) and salal had the highest (30.25%). Lignin content in salal was greater on recently disturbed sites. Astringency ranged from 0.0015 mg protein precipitated per mg plant tissue in vine maple to 0.6737 in trailing blackberry. Salal and willow had intermediate astringencies: elderberry, huckleberry, and vine maple had the lowest. Hydrolyzable tannins were present in all species except red elderberry. Burning and plant association effected astringency and condensed tannin content in trailing blackberry and huckleberry. Samples from burned, very dry and resource-poor sites had higher astringencies than on similar unburned units and non-resource-limiting sites. Condensed tannin contents increased with unit age in salal, huckleberry, and trailing blackberry, possibly accumulating during peak years of re-establishment after disturbance. Vine maple and red huckleberry were the only taxa with positive digestible protein levels. Digestible protein content may be higher in winter forage on less severe sites. Elk forage enhancement in winter range should be evaluated on a site-specific basis. Burning did not promote a detectable increase in quality for these forage taxa, and it decreased the quality of species sensitive to site conditions. Close

• 49. [Article] Persistence and accumulation of clopyralid (3,6-dichloropicolinic acid) in soil

  Field studies were started at Hyslop Farm, Corvallis, Oregon in 1984 to determine the soil persistence of the herbicide clopyralid (3,6-dichloropicolinic acid) under cropping situations. The herbicide ...

  Citation × Citation Citation Abstract Copy Title: Persistence and accumulation of clopyralid (3,6-dichloropicolinic acid) in soil Author: Tanphiphat, Karin Field studies were started at Hyslop Farm, Corvallis, Oregon in 1984 to determine the soil persistence of the herbicide clopyralid (3,6-dichloropicolinic acid) under cropping situations. The herbicide was sprayed on bare soil at the proposed use rate of 0.14 kg/ha in the spring and on the same plots at a high rate of 0.56 kg/ha in the summer. Winter wheat (Triticum aestivum L. 'Stephen') was seeded in the same fall. Treated plots did not yield differently than untreated plots. Safflower (Carthamus tinctorius L.), a crop known to be sensitive to clopyralid, was planted in the spring of 1985 to the area treated with clopyralid in 1984. Safflower grew normally and fresh weights were not reduced. Greenhouse bioassays were conducted on soil samples collected from two separate sets of plots treated with clopyralid in the fall of 1984 or the spring of 1985. The application rates were 0.56 and 1.12 kg/ha. Lentil (Lentilla lens L.), safflower, and peas (Pisum sativum L.) were used as indicator plants. From the plots sprayed in the fall, soil samples were collected at 0, 14, 34, 54, 114, 220, and 287 days after treatment. Clopyralid disappeared faster in the second depth (10 to 20 cm depth) than in the first depth (0 to 10 cm depth). No herbicide was detected in the second depth 220 days after treatment but in the first depth there was sufficient herbicide to cause growth reduction in all of the indicator species. In soil sampled 287 days after applying either 0.56 or 1.12 kg/ha, enough herbicide remained in the first depth to produce slight symptoms on lentil. No herbicide injury was observed on peas or safflower. From plots sprayed in the spring, soil samples were collected 0, 14, 28, and 56 days after treatment. In the spring, clopyralid dissipated more slowly than in the fall, based on the observation that the indicator plants were more severely injured when grown in soil samples collected following the spring application than they were following the fall application. Adding 2,4-D did not affect clopyralid persistence. Clopyralid and XRM-3785 (clopyralid + 2,4-dichlorophenoxy acetic acid) at the same dosage of clopyralid disappeared from the soil at approximately the same time. Title: Persistence and accumulation of clopyralid (3,6-dichloropicolinic acid) in soil Author: Tanphiphat, Karin Field studies were started at Hyslop Farm, Corvallis, Oregon in 1984 to determine the soil persistence of the herbicide clopyralid (3,6-dichloropicolinic acid) under cropping situations. The herbicide was sprayed on bare soil at the proposed use rate of 0.14 kg/ha in the spring and on the same plots at a high rate of 0.56 kg/ha in the summer. Winter wheat (Triticum aestivum L. 'Stephen') was seeded in the same fall. Treated plots did not yield differently than untreated plots. Safflower (Carthamus tinctorius L.), a crop known to be sensitive to clopyralid, was planted in the spring of 1985 to the area treated with clopyralid in 1984. Safflower grew normally and fresh weights were not reduced. Greenhouse bioassays were conducted on soil samples collected from two separate sets of plots treated with clopyralid in the fall of 1984 or the spring of 1985. The application rates were 0.56 and 1.12 kg/ha. Lentil (Lentilla lens L.), safflower, and peas (Pisum sativum L.) were used as indicator plants. From the plots sprayed in the fall, soil samples were collected at 0, 14, 34, 54, 114, 220, and 287 days after treatment. Clopyralid disappeared faster in the second depth (10 to 20 cm depth) than in the first depth (0 to 10 cm depth). No herbicide was detected in the second depth 220 days after treatment but in the first depth there was sufficient herbicide to cause growth reduction in all of the indicator species. In soil sampled 287 days after applying either 0.56 or 1.12 kg/ha, enough herbicide remained in the first depth to produce slight symptoms on lentil. No herbicide injury was observed on peas or safflower. From plots sprayed in the spring, soil samples were collected 0, 14, 28, and 56 days after treatment. In the spring, clopyralid dissipated more slowly than in the fall, based on the observation that the indicator plants were more severely injured when grown in soil samples collected following the spring application than they were following the fall application. Adding 2,4-D did not affect clopyralid persistence. Clopyralid and XRM-3785 (clopyralid + 2,4-dichlorophenoxy acetic acid) at the same dosage of clopyralid disappeared from the soil at approximately the same time. Close

• 50. [Article] The land-water interface : patterns of riparian vegetation and channel morphology in the Oregon Coast Range system

  This study was conducted to describe variation of riparian vegetation in an Oregon Coast Range system according to geomorphic characteristics and in relation to streamflow. Specific objectives of this ...

  Citation × Citation Citation Abstract Copy Title: The land-water interface : patterns of riparian vegetation and channel morphology in the Oregon Coast Range system Author: Takahashi, Mayumi This study was conducted to describe variation of riparian vegetation in an Oregon Coast Range system according to geomorphic characteristics and in relation to streamflow. Specific objectives of this study were to: I) examine if the vegetation composition and structure of the riparian forest varied among channel-reach morphologies, 2) examine how the composition and structure of the riparian forest changed with distance from the stream, and 3) extract major underlying environmental gradients explaining riparian forest community from riparian vegetation data. A 30 m x 30 m sample site was randomly located on each side of upper Camp Creek in each of 19 reaches, and within each site three consecutive 30 m x 10 m belt-transects established perpendicular to the stream flow. Overstory and understory vegetation was sampled in each belt transect. Environmental variables sampled included slope, aspect, height above summer low flow, elevation above sea level. Non-metric Multidimensional Scaling and Indicator Species Analysis was used to describe characteristics of riparian plant communities. Distinct riparian vegetation patterns were observed in upper Camp Creek with increasing distance from stream. Both overstory and understory vegetation quickly changed with increasing distance from stream. Areas within ten meters from stream were characterized as mesic riparian environments while areas twenty meters away from stream were characterized as upland conifer forest environments. Vegetation composition was ordered along an inferred moisture gradient from streamside to hillslope, and distance from stream and height above summer low flow were almost equally correlated to the gradient. Tall shrubs including salmonberry, sword fern and vine maple are important component of riparian vegetation. Channel-reach morphology little differentiated riparian vegetation. A few species were significantly abundant in a specific reach of channel morphology. However, results of this study about relationships between channel-reach morphology and riparian vegetation were inconclusive. Title: The land-water interface : patterns of riparian vegetation and channel morphology in the Oregon Coast Range system Author: Takahashi, Mayumi This study was conducted to describe variation of riparian vegetation in an Oregon Coast Range system according to geomorphic characteristics and in relation to streamflow. Specific objectives of this study were to: I) examine if the vegetation composition and structure of the riparian forest varied among channel-reach morphologies, 2) examine how the composition and structure of the riparian forest changed with distance from the stream, and 3) extract major underlying environmental gradients explaining riparian forest community from riparian vegetation data. A 30 m x 30 m sample site was randomly located on each side of upper Camp Creek in each of 19 reaches, and within each site three consecutive 30 m x 10 m belt-transects established perpendicular to the stream flow. Overstory and understory vegetation was sampled in each belt transect. Environmental variables sampled included slope, aspect, height above summer low flow, elevation above sea level. Non-metric Multidimensional Scaling and Indicator Species Analysis was used to describe characteristics of riparian plant communities. Distinct riparian vegetation patterns were observed in upper Camp Creek with increasing distance from stream. Both overstory and understory vegetation quickly changed with increasing distance from stream. Areas within ten meters from stream were characterized as mesic riparian environments while areas twenty meters away from stream were characterized as upland conifer forest environments. Vegetation composition was ordered along an inferred moisture gradient from streamside to hillslope, and distance from stream and height above summer low flow were almost equally correlated to the gradient. Tall shrubs including salmonberry, sword fern and vine maple are important component of riparian vegetation. Channel-reach morphology little differentiated riparian vegetation. A few species were significantly abundant in a specific reach of channel morphology. However, results of this study about relationships between channel-reach morphology and riparian vegetation were inconclusive. Close