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It is uncertain how predicted changes in climate will impact vegetation responses and plant species’ distributions because the physiological mechanisms underlying thresholds for damage are not well understood, ...
Citation Citation
- Title:
- Approaches for Characterizing Plant Physiological Responses to Environmental Stress
- Author:
- Marias, Danielle E.
It is uncertain how predicted changes in climate will impact vegetation responses and plant species’ distributions because the physiological mechanisms underlying thresholds for damage are not well understood, and responses to stress vary by functional type and developmental stage. Thus, it is crucial to investigate physiological responses to heat and drought stress on multiple species, populations, and growth stages with diverse approaches. In this dissertation, I employ a suite of physiological and modeling methods to inform our knowledge of plant physiological responses to environmental stress in Coffea arabica saplings, Pseudotsuga mensizeii (PSME) and Pinus ponderosa (PIPO) seedlings, and old-growth PIPO. In Chapter 2, I evaluate the effect of leaf age and methodology on the thermotolerance or heat tolerance of C. arabica leaf discs using chlorophyll fluorescence and electrolyte leakage methods. I found that mature leaves were more heat tolerant than expanding leaves, longer time between temperature exposure and measurement yielded more accurate thermotolerance assessments, and photochemistry was more heat-sensitive than cell membranes. To complement the second chapter investigating heat stress responses on detached leaf discs, Chapter 3 examines the effect of leaf age and heat stress duration (45 min or 90 min) on whole-plant physiological responses and capacity to recover in C. arabica by monitoring chlorophyll fluorescence (F[subscript V]/F[subscript M]), gas exchange, and foliar non-structural carbohydrate (NSC) dynamics in situ in response to a simulated heat wave (49°C) in a growth chamber. I found that the 90 min treatment resulted in greater photosynthetic damage and slower recovery than the 45 min treatment, expanding leaves recovered more slowly than in mature leaves, and both heat treatments inhibited flowering. A leaf energy balance model demonstrated that heat stress would be exacerbated by drought-induced stomatal closure. Heat treatment duration significantly impacted NSC dynamics that were closely related to reproduction and repair. Because seedling establishment governs species’ distributions, and because seedlings are particularly threatened by high temperatures at the soil surface, in Chapter 4 I examined the thermotolerance and heat stress responses of PIPO and PSME seedling populations from contrasting climates. Unexpectedly, I found that PSME was more heat tolerant the PIPO. I also monitored physiological recovery after exposure to a simulated heat wave (45°C) by measuring photosynthesis, F[subscript V]/F[subscript M], foliar NSC, and carbon stable isotope ratios (proxy for intrinsic water use efficiency, iWUE). Heat stress responses were consistent with phenotypic plasticity and reflected the conditions under which the plants were grown, while iWUE, a measure of potential drought resistance, was consistent with ecotypic differentiation and the climates from which the seedlings originated. To investigate responses to environmental stress on larger temporal and spatial scales without the challenges of making repeated physiological measurements on old-growth trees, in Chapter 5 I used long-term trajectories of tree-ring growth and carbon and oxygen isotopes of tree-ring cellulose (δ¹³Ccell, and δ¹⁸Ocell) to successfully predict the stand characteristics of two sets (upland, riparian) of old-growth PIPO using the Physiological Principles in Predicting Growth (3-PG) model, the δ¹³Ccell submodel, and a δ¹⁸Ocell submodel added by me. The expanded model helped to explain physiological drivers underlying the different tree-ring growth, δ¹³Ccell, and δ¹⁸Ocell trajectories measured at the upland and riparian sites. The combination of both δ¹⁸O and δ¹³Ccell submodels provided a useful and novel way to constrain 3-PG. This dissertation demonstrates an innovative strategy of applying diverse approaches to understand the physiological mechanisms behind vegetation responses to environmental stress.
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1272. [Article] A 37,000-year record of paleomagnetic and environmental magnetic variability from Burial Lake, Arctic Alaska
Burial Lake sediments from the Noatak Basin in the northwest Brooks Range of Arctic Alaska (68.43°N, 159.17°W, 21.5 m water depth) provide the oldest continuous lacustrine record of paleo-environmental ...Citation Citation
- Title:
- A 37,000-year record of paleomagnetic and environmental magnetic variability from Burial Lake, Arctic Alaska
- Author:
- Dorfman, Jason Michael
Burial Lake sediments from the Noatak Basin in the northwest Brooks Range of Arctic Alaska (68.43°N, 159.17°W, 21.5 m water depth) provide the oldest continuous lacustrine record of paleo-environmental change and paleomagnetic secular variation (PSV) in eastern Beringia. A precise radiocarbon chronology, determined through accelerator mass spectrometry (AMS) allows us to independently constrain the region's climatic and geomagnetic evolution over the last ~37,000 years. Progressive alternating field (AF) demagnetization of u-channel samples and additionally acquired physical, geochemical, and rock-magnetic datasets, reveal three distinct lithologic subunits associated with the last glacial period (37.2 - 19.4 ka), the deglacial transition (19.4 - 9.8 ka), and the Holocene (9.8 ka - present). Rock magnetic variability suggests changes in sediment provenance associated with the transition from glacial to interglacial conditions. This is interpreted to result from a variable flux of aeolian derived sediment, and is supported by complimentary internal proxy data from Burial Lake. Other regional paleoclimate data, various glacial chronologies for the Brooks Range, and a relative sea level reconstruction facilitate a discussion of possible local, widespread, and far-field sources of dust, and the time-dependency of potential forcing mechanisms governing its production, availability, transport, and deposition. Results indicate an overall reduction in dust input from the glacial period to the Holocene that is largely attributed to increases in terrestrial and aquatic productivity, warming, and moisture availability, which limited widespread landscape deflation and production of dust. Subaerial continental shelves may have provided significant far-field sources of dust to interior Alaska during the glacial period, that were shut off by sea level inundation following the Last Glacial Maximum (LGM; 19 - 26.5 ka), further contributing to diminishing dust emissions. While glacial activity in the Brooks Range may provide local revenue of dust, activation of those deposits and timing of deposition in Burial Lake often appears to be more directly linked with general aridity, lack of vegetative cover, and increased windiness, rather than glacial advances or retreats. Despite this lithologic complexity, we isolate a stable, single-component characteristic remanent magnetization, carried predominately by low-coercivity (titano)magnetite in the pseudo single-domain (PSD) to multi-domain (MD) magnetic grain size range. We reconstruct directional paleomagnetic secular variation (PSV) over the full length of the record, and relative paleointensity (RPI) for the last ~14,700 years, which are consistent with available regional PSV records and continuous spherical harmonic model outputs. We observe only small deviations from geocentric axial dipole (GAD) predictions during the Holocene, while larger amplitude directional features are prevalent before 10 ka, and inclinations lay significantly shallower than GAD. While this may be related to lithology and the sediment magnetic acquisition process, regional records (including those derived from lava flows) indicate similar Holocene-Pleistocene discrepancies. Following on the "eccentric dipole" hypothesis, subdued secular variation and GAD-like behavior in the Pacific appears confined to the Holocene high-intensity state, showing greater variability as Pleistocene field strength diminishes, and/or the dipole axis is shifted away from the Pacific hemisphere. Long period trends in PSV from in the Alaskan Arctic are also similar in character to far-field sites (e.g., Hawaii and Siberia), suggesting large-scale coherent core-fluid flow regimes, expressed over surface geographical extents >5,000 km, and spanning Holocene-Pleistocene time intervals. The well-dated Burial Lake record fills a significant data gap in the growing Holocene paleomagnetic database, while allowing us to extend our understanding of PSV beyond the Holocene and into the Pleistocene, and continue the development of regional stratigraphic dating curves.
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1273. [Article] Sedimentation, economic enrichment and evaluation of heavy mineral concentrations on the southern Oregon continental margin
Heavy minerals can contain potentially economic amounts of metals as both matrix and trace constituents. Such minerals appear as unconsolidated black sands on the continental shelf off southwest Oregon ...Citation Citation
- Title:
- Sedimentation, economic enrichment and evaluation of heavy mineral concentrations on the southern Oregon continental margin
- Author:
- Bowman, Kenneth Charles Jr
Heavy minerals can contain potentially economic amounts of metals as both matrix and trace constituents. Such minerals appear as unconsolidated black sands on the continental shelf off southwest Oregon and along the Oregon coast. Two diverse energies are considered in this investigation. Environmental energy of the depositional regimen, Part I; energy involved in crystallization of transition metals from a magma, Part III. In Part II, an analytical scheme for the evaluation of opaque oxides is proposed, and an examination of the results as applied to two samples is presented. Part I The unconsolidated black sands on the Oregon continental margin have been profoundly affected by tectonic uplift aid by cyclic erosive transgression and regression. Progressive enrichment in heavy minerals from the Klamath Mountains has apparently occurred during each glacio-eustatic regression of the Pleistocene seas, each regression a period of intensified erosion and sediment transport. Subsequent erosive transgressions selectively sort and redistribute these heavy minerals into paralic beach and nearshore deposits. Uplift of the coast and shelf implies that the heavy minerals were reworked during the Holocene transgression into concentrations of greater extent and higher ore tenor than relict deposits of earlier transgressions in upraised Pleistocene terraces. Extrapolation of ore reserve values from the terraces by "Mirror Image" concepts might seriously underestimate the potential of offshore deposits. Offshore heavy mineral concentrations should be coincident with observed submarine terraces. Part II An analytic scheme was developed to investigate opaque oxides in two samples; one from the Pleistocene terraces; the other from near the present shelf edge. Analyses involving X-ray diffraction techniques, atomic absorption and neutron activation established the mineralogy and elemental distribution in magnetically separated diagnostic splits. Chrome spinel, ilmenite and magnetite comprise the opaque oxide fraction in both samples. Correlation studies of these analyses suggest: (1) Chromium is a matrix metal of chrome spinel and is diadochic into magnetite. (2) Iron appears in all opaque oxides and in increasing amounts with increasing magnetic susceptibility. (3) Titanium is a matrix metal in ilmenite, and diadochic into chrome spinel and magnetite. (4) Nickel and ruthenium are diadochic into and correlated to the spinel structure; i.e. to chrome spinel and magnetite. (5) Osmium appears to be correlated to chromium. (6) Zinc is limited to spinel in these samples. Part III Goldschmidt's and Ringwood's criteria for diadochy often fail to explain the distribution of the transition metals because crystal field effects are not considered. Favored d[superscript n] configurations, e.g. octahedrally coordinated, low spin d⁶ cations in the spinel minerals, result in shortened interatomic distance and significantly strengthened cation-ligand bonds, possibly affecting the distribution of such metal cations. The octahedral site preference energy parameter (OSPE) has been used to explain distributional behavior of the first (3d) transition series metals. OSPE calculations for four low spin d⁶ cations - Co(III), Ru(II), Rh(III), and Pt(IV) - give significantly high values for this parameter. High OSPE valued transition metal cations possibly form stable proto-mineral oxide complexes in the magma which persist through crystallization. These associations predetermine the enrichment of transition metals in oxide minerals and act as nuclei during cooling and solidification. Subduction of oxidized and hydrolyzed near-surface rocks down a Benioff zone provides progressively higher Eh in the magma, a variety of cation oxidation states, and water for sepentinization of ultramafic rocks. The distribution of the platinum metals in a strongly reducing magma environment should be different than in the oxidizing magma proposed for the Klamath ultramafics. The OSPE parameter offers an explanation for the observed distribution of platinum group metals in spinel minerals from this investigation, in chromites from Uralian dunitic massifs and the Stillwater complex; and of iridium from the Great Lake Doleritic Sheet, Tasmania. Chrome spinel from Oregon had twice the concentration of ruthenium, and one-third the amount of osmium as similar Uralian chromite deposits. The first significant concentration of ruthenium in magnetite is herein reported recommending continued research into the platinum metal distribution in southwest Oregon.
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The physical and chemical properties of soils greatly affect the toxicity of bromacil and picloram. Consequently, a knowledge of the parameters which influence the soil inactivation of these herbicides is ...
Citation Citation
- Title:
- Surfactant effects on bromacil and picloram adsorption by Oregon soils
- Author:
- Gaynor, John Donald
The physical and chemical properties of soils greatly affect the toxicity of bromacil and picloram. Consequently, a knowledge of the parameters which influence the soil inactivation of these herbicides is necessary to determine proper application rates for good weed control. Enhancement in phytotoxicity with the addition of surfactants or surface active agents in the spray volume has been observed for these chemicals; however, little is known concerning the effects of these additives on picloram and bromacil adsorption. The objectives of this research are: 1) to evaluate the effects of cation saturation on bromacil adsorption by montmorillonite, 2) to determine the effects of pH and organic matter on the adsorption of bromacil and picloram by soils and 3) to determine the effects of dilute solutions of four surfactants on the adsorption of bromacil and picloram by soils. The adsorption of 2-¹⁴C-labeled bromacil on Ca²⁺, Cu²⁺ and Al³⁺ saturated montmorillonite was determined after equilibration a. 0° and 25°C. Seven concentrations of 2-¹⁴C-labeled bromacil and ¹⁴C-carboxyl labeled picloram were equilibrated without surfactant with nine Oregon soils at 25°C. Labeled bromacil and picloram at 5 ppm and 10 ppm concentration in 1% and 10% surfactant solution were also equilibrated at 25°C with eight of the above soils. After equilibrium the montmorillonite and soil samples were centrifuged and analyzed on a liquid scintillation counter for bromacil and picloram remaining in solution. The adsorption of bromacil at 25° and 0°C for each cationic saturated montmorillonite and at 25°C by the nine Oregon soils increased with concentration according to the Freundlich equation, Bromacil adsorbed on the montmorillonite increased with cation saturation in the order Ca²⁺ < Cu²⁺ < Al³⁺. The overall adsorption of bromacil was reduced when the temperature was increased to 25°C. Bromacil adsorbed on the cation saturated rnontmorillonite may occur by complexation of the Cu²⁺ or Al³⁺ cations with the ring N at the one position of the bromacil or by induction through a pH effect. The increased adsorption at the lower temperature may be due to a change in water solubility or adsorption energy. The equilibration of bromacil with the nine Oregon soils indicated organic matter was the most important parameter affecting adsorption. A highly significant correlation coefficient of 0.913 was calculated between the Freundlich K value for bromacil adsorption and organic matter. Bromacil adsorption in the low organic matter soils appeared to be directly correlated with an increase in exchangeable aluminum or pH as observed in the montmorillonite study. However, the wide range in organic matter at the intermediate level limited the opportunity to correlate bromacil adsorption with aluminum or pH. The adsorption of bromacil increased in the presence of the 1% cationic and anionic surfactants and decreased in the presence of the 1% nonionic surfactant solution compared to that without surfactant. Regardless of surfactant type the 1% surfactant solutions greatly decreased the variable effects of organic matter on bromacil adsorption in the Minam and Kinney soil series but not the Woodcock soil series. Bromacil adsorption from the 10% concentration of each surfactant type was greatly reduced compared to adsorption from the 1% surfactant solution. Strangely, the adsorption of bromacil from surfactant solution was always less in the Woodcock soil series than in the Minam and Kinney soil series. Picloram adsorption increased with concentration on the nine soils according to the Freundlich equation. A significant negative correlation coefficient of 0.667 was calculated between the Freundlich K value for picloram adsorption and pH; however, the interaction between pH and exchangeable aluminum could not be isolated. Complexation of picloram with exchangeable aluminum and adsorption of the molecular species by organic matter appeared to be the principle modes of adsorption. The adsorption of picloram by soils increased in the presence of the 1% cationic and nonionic surfactant solutions and decreased in the 1% anionic surfactant solution compared to that without surfactant. Adsorption in the presence of 1% cationic surfactant solution occurred from the molecular and ionic species as indicated by equal adsorption in the Minam (pH = 7) and Kinney (pH = 5) soil series. The 10% cationic surfactant solution decreased adsorption from that in the 1% surfactant solution; however, an inverse relationship between organic matter and adsorption was evident in the Minam and Kinney soil series. Adsorption from the nonionic surfactant solution was independent of surfactant concentration but decreased as pH increased. The 1% anionic surfactant solution effectively competed with picloram for adsorption sites. However, the 10% surfactant solution increased adsorption from that in the 1% surfactant solution possibly due to the creation of adsorption sites for picloram by the adsorbed surfactant. Increased phytotoxicity of bromacil and picloram has been observed by others when a nonionic surfactant was introduced into the spray solution. The results of this study indicate that part of the increased toxicity may be due to reduced soil adsorption of the chemicals in anionic and nonionic surfactant solutions. The addition of a cationic surfactant, on the other hand, may increase adsorption and provide poor weed control at recommended rates. Further investigation is required to determine if the herbicides adsorbed by the surfactant are available for root uptake and if the soil applied surfactant is phytotoxic.
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1275. [Article] Spatial Association of Humpback Whales (Megaptera novaeangliae) and their Prey in the Southern Gulf of Maine, USA
Efficient foraging strategies result in a predator spatially overlapping with its prey, foraging in the most profitable patches, and minimizing the time transiting between patches. Previous studies investigating ...Citation Citation
- Title:
- Spatial Association of Humpback Whales (Megaptera novaeangliae) and their Prey in the Southern Gulf of Maine, USA
- Author:
- Kirchner, Theresa
Efficient foraging strategies result in a predator spatially overlapping with its prey, foraging in the most profitable patches, and minimizing the time transiting between patches. Previous studies investigating baleen whale foraging strategies have generally focused on investigating spatial overlap with prey patches, patch profitability or movement within feeding grounds. The present study investigated the fine-scale strategies of movement between individual prey schools and larger prey patches in humpback whales (Megaptera novaeangliae) bubble-feeding on sand lance (Ammodytes spp.) in and around the Stellwagen Bank National Marine Sanctuary, USA. The goal was to investigate the presence of hierarchically nested spatial structures in both sand lance patches and whale bubble-feeding behavior, and to compare the scales and geometry of these patches between predator and prey behavior on each hierarchical scale. Furthermore, the profitability of sand lance schools in feeding areas was investigated. Using animal-borne tag technology to record underwater movement of whales in combination with surface observations of whale behavior, the locations of bubble-feeding events were identified. Concurrent hydroacoustic measurements of the prey distribution in the water column were used to identify the locations and energetic parameters of sand lance schools around tagged whales. First Passage Time analysis was used to determine the spatial scale of individual bubble-feeding events. Based on spatial proximity, feeding events and prey schools were grouped into larger feeding bouts and prey patches to investigate the presence of hierarchically nested scales. Up to three hierarchy levels were found in bubble-feeding behavior of nine whales tagged on six days between 2008 and 2012, and up to five hierarchy levels in the sand lance prey field around the tagged whales. There was a significant positive correlation between the lengths of whale bubble-feeding bouts and the lengths of sand lance patches over three common hierarchy levels. On each hierarchy level, the lengths of whale bubble-feeding bouts were significantly smaller than those of sand lance patches. Mean inter-feeding bout distances were significantly positively correlated with mean inter-prey patch distances over two hierarchy levels. Mean distances between feeding events were similar to the mean distances between prey schools. On larger hierarchy levels, mean inter-bout distances were greater than mean distances among prey patches. Mean school height and density tended to be greater in schools recorded inside than outside of feeding bout areas. The prey field structures found here were likely a result of the specific habitat requirements of sand lance. The results of this study suggest that the tagged whales were able to adapt their foraging movement to the structure of the prey field. By feeding on neighboring schools, whales could minimize the time spent between prey schools. On larger spatial scales, whales did not feed on neighboring prey patches. This could be a result of decreased abilities to find the nearest patch, or because, rather than restricting their foraging movement to neighboring patches, the whales were targeting specific patches. The foraging movement observed in this study led to spatial overlap of the tagged whales with sand lance schools that were characterized by properties rendering them more energetically profitable for bubble-feeding whales. While hierarchically structured foraging movement has been found in other marine predators, this is the first study that demonstrates this kind of foraging mechanism for baleen whales.
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Riparian ecosystems play numerous and essential roles related to the quality and flow of water, and food/habitat for fish, and varieties of wildlife. Due to lateral and linear linkages throughout the landscape, ...
Citation Citation
- Title:
- The ecology of riparian ecosystems of Northeast Oregon : shrub recovery at Meadow Creek and the structure and biomass of headwater Upper Grande Ronde ecosystems
- Author:
- Case, Richard L.
Riparian ecosystems play numerous and essential roles related to the quality and flow of water, and food/habitat for fish, and varieties of wildlife. Due to lateral and linear linkages throughout the landscape, these zones influence the integrity of the terrestrial as well as the entire aquatic-riverine ecosystem. Since Euro-American settlement in the West, the structure and condition of many riparian ecosystems has been significantly altered. To provide tools and an ecological perspective related to riparian restoration and management, and to document late 20th century headwater riparian structure and biomass in the Upper Grande Ronde Basin, this research project was undertaken. At Meadow Creek, the response of riparian hardwood species to the termination of livestock grazing was quantified. Regression equations were developed to predict shrub biomass. Permanently marked hardwood plants were measured annually to quantify parameters of growth (height, crown area, mainstem diameter, number of stems, biomass). Permanent belt transects on gravel bars were utilized to quantify rates of shrub establishment. Elk/deer-proof exclosures allowed the quantification of the browsing influence of wild ungulates. In 1991, initial shrub heights and densities reflected decades of grazing pressure. Mean heights of515 woody plants (14 species) was 47 cm and densities on gravel bars averaged 10.7 plants/100m². After two seasons without livestock grazing, mean crown volumes of willows (Salix spp.) increased 550% inside of wild ungulate exclosures and 195% outside, black cottonwood (Populus trichocarpa) 773% inside and 808% outside, and thin-leaf alder (Almis incana) 1046% inside and 198% outside, respectively. Willows were significantly impeded (p<0.Ol) mule deer and Rocky Mountain elk, alder samples were too small to statistically test, and cottonwood was not significantly impeded. However, impacts by deer and elk may be exaggerated due to high densities and the ungulate density-dynamics unique within the 77 km² Starkey Experimental Forest big-game enclosure surrounding the study site. Establishment rates are low at this time, i.e., only 10% of previously suppressed willows produced catkins. Although in transects densities increased by 5 new woody plants/lOOm² (50m of streambank). Other non-anthropogenic factors influencing the recovery of shrubs, included beaver which removed mainstems from 20% of willows, 11% of thin-leaf alder, and 4% of black cottonwood, and active insect defoliation which was noted on 16% of willows, 7% of thin-leaf alder, and 0% of black cottonwood. Crude protein levels measured in willow and alder leaves was relatively high (16.1 to 16.3%) helping to explain their palatability and use by wild and domestic herbivores. Few studies have quantified biomass, structure and composition of headwater riparian ecosystems. Data such as this are important given their dominant roles in ecosystem biodiversity, and aquatic function. To document relatively intact forested headwater ripanan conditions in the Upper Grande Ronde Basin, the biomass, structure and composition along six headwater reaches was quantified. Sampling was done using a nested belt transect/plot arrangement along 500 meter reaches. Total aboveground biomass (TAGB) ranged from 203 to 261 Mg/ha, with overstory conifers contributing 101 to 177 Mg/ha. Living understory components (saplings, seedlings, shrubs, and herbs) comprised 5 to 18 Mg/ha (2 to 9% of TAGB), while forest floor detrital accumulations comprised 65 to 101 Mg/ha (29 to 42% of TAGB). Average shade per day for July, 1993 ranged between 53% and 75%, reducing the unshaded solar energy potential of 2390 Mj/day to between 680 and 1280 Mj/day striking each m² of stream surface. This baseline reference information can serve in multi-disciplined research, as well as, be a basis for long term studies of natural systems responding to changing climate and different resource management scenarios.
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1277. [Article] Avian Radar Baseline Study: Final Survey Report for the Proposed Reedsport Ocean Power Technologies Wave Park
Geo-Marine, Inc. (GMI) conducted an offshore avian radar baseline study for Oregon Wave Energy Trust (OWET) for a wave energy study located northwest of Reedsport, Oregon from 25 August through 29 October ...Citation Citation
- Title:
- Avian Radar Baseline Study: Final Survey Report for the Proposed Reedsport Ocean Power Technologies Wave Park
- Author:
- Geo-Marine, Inc.
Geo-Marine, Inc. (GMI) conducted an offshore avian radar baseline study for Oregon Wave Energy Trust (OWET) for a wave energy study located northwest of Reedsport, Oregon from 25 August through 29 October 2010. The study was conducted from shore with GMI’s Mobile Avian Radar System (MARS®). The MARS® was equipped with a 3-centimeter (cm) wavelength 50-kilowatt (kW) radar with a 2.5-degree (°) parabolic antenna for horizontal scanning, and a 3-cm, 25-kW radar with an open array antenna for vertical scanning. Diurnal land-based nearshore and diurnal and nocturnal boat-based radar validation surveys were conducted specifically to determine whether the radar could detect birds flying at low attitudes above the water. Comparison between the nearshore and offshore (study area) observer bird passage rates and the nearshore and offshore radar passage rates revealed low correlation between diurnal observations and radar data. The correlation analysis values were all too low (<.307) to develop a correction factor to apply to the radar data. Sea clutter was identified as the limiting factor. When algorithms to reduce false tracks from sea clutter were applied, tracks of real birds were eliminated because they could not be separated from sea clutter false tracks. At present there is no technology known that can accurately remove bird detections from sea clutter. This problem was further magnified in this study because radar visual validation surveys revealed that a major portion of the bird movement both nearshore and offshore occurred at altitudes from 1-30 feet (ft) above sea level. At that altitude it is impossible to separate birds from wind-driven waves and high swells that are common in the study area during fall. The visual validation data documented that the radar was ineffective when birds were flying close to the surface. In addition to providing data to facilitate passage rate comparisons between observer and the radar, the radar validation surveys provided data on bird flight behaviors within and adjacent to the study area. These data, which were requested to be collected for this study, included information on nearshore and offshore (study area) bird species occurrence, passage rates, flight altitudes and speeds, flight directions, and flock sizes. During the diurnal land-based nearshore avian surveys 43 bird species were identified; 32 bird species were observed during the boat-based offshore surveys. One federally-listed bird species, Marbled Murrelet (threatened), was observed occasionally during nearshore and offshore surveys. Diurnal nearshore bird passage rates ranged from 30-390 birds/nautical mile (NM)/hour (hr) from 0 to 1 NM offshore and from 10-142 birds/NM/hr from 1 to 2 NM offshore. Offshore (study area) passage rates ranged from 142-268 birds/NM/hr; offshore nocturnal passage rates ranged from 3-53 birds/NM/hr. The majority of birds flying over both nearshore (94%) and offshore (93%) waters were flying from 1-100 ft above sea level (asl). The majority of these birds were flying from 1-30 ft asl (nearshore, 75%; offshore, 83%). The dominant flight directions were to the south and the majority of birds sighted were in the 1-5 flock category. This Avian Radar Baseline Study was contracted to assist in collecting data that could potentially be used to meet these requirements. Avian radar validation surveys were designed specifically by GMI for this study to determine the accuracy of the radar data in predicting the number of birds that would potentially collide with the 30-ft tall wave buoys. The results of the avian radar validation surveys from this study indicate that avian radar is not able to collect accurate altitude flight data within the potential bird-wave power buoy collision zone (1-30 ft asl) because of the presence of sea clutter (high wind waves and/or swells) in the study area; however, diurnal avian radar validation bird survey data collected from shore and from a boat in the study area provided information requested by the Scope of Work including on nearshore and offshore (study area) species occurrence, avian passage rates (number of bird tracks/NM/hr), frequency of avian flight altitudes within and above the bird-wave power buoy collision zone, flock size frequency, and flight direction frequency. In addition, a nocturnal thermal imaging camera was used to conduct nighttime avian studies and provided data on nighttime bird passage rates. GMI recommends, based on the findings of this Avian Radar Baseline Study, that seasonal radar studies recommended by the FERC Study Plan be replaced with diurnal boat surveys and nocturnal boat surveys using stabilized remote sensing technologies (e.g., thermal imaging, high definition cameras). These methods will, in GMI’s opinion, provide the best data on nocturnal passage rate (bird abundance) and altitude use within the potential bird-wave power buoy collision zone (1-30 ft asl).
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1278. [Article] Breeding ecology and nest site selection of Kittlitz's murrelets on Kodiak Island, Alaska
The Kittlitz's murrelet (Brachyramphus brevirostris) is a rare member of the seabird family Alcidae that breeds in coastal areas of Alaska and Beringian Russia. The species belongs to the genus Brachyramphus, ...Citation Citation
- Title:
- Breeding ecology and nest site selection of Kittlitz's murrelets on Kodiak Island, Alaska
- Author:
- Lawonn, Matthew James
The Kittlitz's murrelet (Brachyramphus brevirostris) is a rare member of the seabird family Alcidae that breeds in coastal areas of Alaska and Beringian Russia. The species belongs to the genus Brachyramphus, an unusual seabird taxon in which all three extant species nest non-colonially, situating their nests up to 75 km inland from coastal marine waters. This nesting strategy is different from that of most seabird species, which tend to nest colonially on remote islands or sea cliffs, where terrestrial predators are generally absent or cannot easily access nests. Within the genus Brachyramphus, Kittlitz's murrelet is notable because a majority of the global population appears to nest on the surface of the ground in rocky alpine habitat near inland or tidewater glaciers, foraging in adjacent marine waters influenced by glacial outflows. The unusual nesting habits of Kittlitz's murrelet have made the study of its nesting ecology difficult, and gaps therefore exist in our understanding of the species' breeding biology. Kittlitz's murrelet populations have declined substantially in core areas of its range, causing the U. S. Fish and Wildlife Service to designate the species as a candidate for protection under the Endangered Species Act. A better understanding of Kittlitz's murrelet nesting ecology is crucial for determining potential causes of these declines and for future management of the species. To this end, I studied Kittlitz's murrelet breeding ecology and nest site selection during 2008-2011 on Kodiak Island, Alaska, in an unglaciated area that was recently found to have large numbers of accessible nests. I and my colleagues found 53 active Kittlitz's murrelet nests in inland scree-dominated habitats and placed remote, motion-sensing cameras at 33 nests. Adults exchanged incubation duties at the nest every 24 or 48 h, almost exclusively during early morning twilight. Following hatching of eggs, parents provisioned their single nestling with an average of 3.9 to 4.8 fish per day, depending on the year. Parental visits to the nest during chick-rearing occurred primarily after sunrise in the early to mid-morning hours, and during evening twilight. Fish were delivered singly to the chick, and Pacific sand lance (Ammodytes hexapterus), a high-lipid forage fish, accounted for about 92% of all identifiable chick meal deliveries. Chick growth rates were high relative to confamilial species, consistent with the high quality of chick diets; the logistic growth rate constant (K) was 0.291, greater than that for any other semi-precocial alcid. Chicks fledged an average of 24.8 d after hatching and asymptotic chick body mass averaged about 135.5 g, approximately 58% of adult body mass. Age at fledging, asymptotic chick body mass (% adult mass), and the number of meal deliveries required to fledge a chick were all lower than or as low as any other species of semi-precocial alcid. The average estimated nest survival rate during 2008-2011 was 0.093 (95% CI = 0.01–0.30), which is extremely low compared to other species in the family Alcidae, and is almost certainly insufficient to sustain a stable population. The primary causes of nest failure were depredation (47% of total nest fates), mostly by red foxes (Vulpes vulpes), and unexplained nestling mortality on the nest (21% of nest fates). Saxitoxin and/or pathogenic endoparasite burdens were observed in five of six necropsied chick carcasses, suggesting possible causes for chick mortality not directly attributable to predation. Habitat characteristics of Kittlitz's murrelet nest sites differed significantly from unused sites at several scales. At a small scale (within 5 m of the nest), nest sites had a lower percent coverage of vegetation and higher percent coverage of intermediate-sized rocks (5–30 cm diameter), compared to randomly selected unused sites. Nest sites were also located on steeper, more north-facing slopes compared to randomly selected sites. Nest sites also had a lower percent coverage of vegetation than randomly-selected sites at larger scales (within 25 m and 50 m of the nest site). Nest sites were located significantly farther from the edge of densely-vegetated habitats than random sites. There was no evidence that nest sites were different from randomly-selected sites in terms of elevation, proximity to ridgelines, or proximity to the open ocean, although a low degree of variation within the study area for these habitat characteristics may have precluded detection of potential differences. Nest survival rates did not co-vary with slope, percent vegetation coverage, distance from vegetated edges, or percent cover of intermediate-sized rocks; however, this result may be an artifact of a limited sample size. The results of this thesis will provide managers with a better understanding of the factors that may limit Kittlitz's murrelet nesting success, such as nest predation and forage fish availability, as well as factors that may influence the quality and distribution of Kittlitz’s murrelet nesting habitat in the future, given on-going and progressive climate change.
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1279. [Article] Conserving energy by safe environmentally acceptable practices in maintaining and procuring transmission poles: third annual report ; June 1983
ABSTRACT Improved Fumigants After 13 years, chioropicrin, methylisothiocyanate (MIT), Vapam, and Vorlex continue to effectively control internal decay of pressure-treated Douglas-fir transmission poles. ...Citation Citation
- Title:
- Conserving energy by safe environmentally acceptable practices in maintaining and procuring transmission poles: third annual report ; June 1983
- Author:
- Oregon State University, Oregon State University. Dept. of Forest Products
ABSTRACT Improved Fumigants After 13 years, chioropicrin, methylisothiocyanate (MIT), Vapam, and Vorlex continue to effectively control internal decay of pressure-treated Douglas-fir transmission poles. The estimated retreating schedules for application of these fumigants to treated wood may be as long as 10 years for Vapam and 15 years for the others. The close-tube bioassay, developed during this research, has proven to be an effective method for determining the persistence of these fumigants in wood and should help in determining when fumigant-treated poles should be retreated. The use of gelatin to encapsulate MIT for wood treatment was ideal because the capsules did not react with MIT, were MIT impermeable when dry, permitting prolonged storage without significant fumigant loss, and readily released MIT when moistened in the wood. Although release of encapsulated MIT in the wood was enhanced by small amounts of water, excess moisture appeared to hinder MIT diffusion into wood. Assays of Vapam treated wood show that the amount of MIT released by breakdown of Vapam is significantly lower than the expected theoretical yield from this fumigant. Encapsulated MIT reduced the decay fungus population in poles in service more effectively than applications of Vapam. The effectiveness of a fumigant in controlling decay may be expressed as the product of the fumigant concentration (C) and the time (T) the decay fungus is exposed to the fumigant before it succumbs. A higher value indicates a less effective treatment. In wood, the CT value obtained for MIT was two times greater at 20% wood moisture content (MC) than at 40 and 75% MC. Although MIT was least effective at 20% MC, there was more MIT i bound to the wood than at the higher moisture levels. This suggests that the MIT bound to the wood structure may be less effective against decay fungi than the MIT in the air and water in the wood. Although the effectiveness of MIT varied with the wood MC, it was nevertheless still very fungitoxic over a broad range of moisture levels. In chioropicrin treated wood, inhibition of invasion by decay fungi was indicated by the lysis and vacuolation of the fungal hyphae in the wood. Chloropicrin appears to hydrogen bond to wood and may form covalent bonds with phenolic wood extractives and lignin, possibly increasing the persistence of the treatment. Controling decay of cedar sapwood Three waterborne fungicides have been added to the previously selected materials being tested on cedar pole sections at an O.S.U. test site as potential substitutes for the pentachiorophenol in oil treatment currently used. The effectiveness of all treatments will be evaluated later this year using the Aspergillus bioassay and a modified soil block test. The most effective treatments then will be tested on poles in service. Bolt-hole protection Later this year cores will be removed from the control bolt holes to evaluate the extent of natural fungal colonization. If a sufficient level of colonization has occurred, the effectiveness of the various chemical treatments in preventing decay in field-drilled bolt holes in Douglas-fir poles will be evaluated. Detecting decay and estimating residual strength in poles A serological technique for rapid detection of decay fungi was found to cross react with non-decay fungi and thus lackedthe necessary specificity for identifying decay fungi in wood. Additional work is needed to purify the preparations to render them more specific to decay fungi. Measurements of modulus of rupture (MOR), modulus of elasticity (MOE), work to maximum load, specific gravity, radial compression strength (RCS), and Pilodyn pin penetration of sound appearing wood containing decay fungi were not significantly different from the corresponding values for wood from which no decay fungi were isolated. However, tests of poles with more advanced decay did show significant reductions in wood strength properties. Specific gravity alone was not a good predictor of bending strength of wood from decayed poles, but the use of both specific gravity and RCS tests significantly improved the ability to predict the bending strength of these wood samples. Decay of Douglas-fir poles prior to pressure treatment The continued study of the fungal infestation of poles during air seasoning has demonstrated that there is a significant buildup of Poria carbonica, the major pole decay fungus, with time. In general, as air seasoning time increased, decay fungi infested more poles and occupied more wood within each pole. Sampling of freshly cut poles in the forest this past year showed that some contained potential decay fungi prior to reaching the pole yard. Frequent isolation of decay fungus monokaryons throughout the air seasoning period suggests that spores of these fungi were infesting the poles at a relatively constant rate. The ability of the basidiomycetes isolated from these poles to reduce wood strength will be evaluated in rapid tests for toughness by impact breaking and changes in the breaking radius of Douglas-fir test sticks. iv The germination of basidiospores of P. carbonica was studied on culture medium and laboratory techniques are being developed to follow germination on a wood surface under varying environmental conditions to further illucidate their role in the infestation of seasoning wood. Exposure of sterilized pole sections at four Pacific Northwest air seasoning sites for successive 3-month periods has been continued. The dramatic increase in infection during Nov.-Jan. '81 at all locations except Arlington WA, did not reoccur in that same time period during 1982. There was, however, a continuing low level of infection at all sites during the year with a slight peak of infection in May-June '82 in Arlington WA. The results of these tests are currently being computer analyzed to more effectively study the patterns of fungal invasion of wood as influenced by environmental factors.
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1280. [Article] Surface-subsurface geology of the middle to upper Eocene sedimentary and volcanic rock units, western Columbia County, northwest Oregon
The middle to upper Eocene Tillamook Volcanics form the basement in the Rock Creek - Rocky Point area. These tholeiitic to alkalic basalts, basaltic andesites, and andesites were erupted as shield volcanoes ...Citation Citation
- Title:
- Surface-subsurface geology of the middle to upper Eocene sedimentary and volcanic rock units, western Columbia County, northwest Oregon
- Author:
- Berkman, Thomas Anthony
The middle to upper Eocene Tillamook Volcanics form the basement in the Rock Creek - Rocky Point area. These tholeiitic to alkalic basalts, basaltic andesites, and andesites were erupted as shield volcanoes seaward of the strandline ontop of an older deep-marine mudstone unit (Yamhill Formation) and an accreted portion of oceanic seafloor (lower Eocene Siletz River Volcanics). The subaerial flows are predominantly aphyric with subordinate plagioclase-augite porphyritic flows with pilotaxitic texture. The overlying Hamlet formation (informal) is composed of three members which document a marine transgression over subsiding islands of Tilamook Volcanics in the middle to late Eocene. The stratigraphically lowest Roy Creek member is composed of basaltic boulder to cobble conglomerate grading upward into fossiliferous pebbly basaltic sandstone deposited around sea stacks and along a high-energy rocky coastline composed of Tillamook Volcanics. Continued subsidence and transgression resulted in deposition of the Sunset Highway member of the Hamlet formation, which conformably overlies the Roy Creek member. The Sunset Highway member consists of interbedded micaceous arkosic sandstone and siltstone with rare basaltic grit beds occurring near the top of the member. Molluscan fauna, faint low-angle cross-bedding, parallel laminations and bioturbation in these sandstones are interpreted to represent deposition in a high-energy inner shelf environment. The upper Narizian (upper Eocene) Sweet Home Creek member conformably overlies the Sunset Highway member in western Columbia and eastern Clatsop counties and is composed of two lithofacies. The dominant lower facies consists of micromicaceous and carbonaceous silty mudstone which contains abundant Foraniinifera indicative of outer neritic to tipper bathyal water depths. Thin-bedded micaceous arkosic turbidite sandstones in nested channels of the upper facies are locally present near the top of the unit and represent deposits of a channelized shelf-slope break. Abrupt sea level regression coupled with increased sedimentation rates due to tectonic unroofing in source areas in Idaho and Washington resulted in abrupt shallowing of sedimentation before deposition of the overlying Cowlitz Formation (C & W sandstone member). The C & W sandstone in cores from the Mist Gas Field and outcrops in the Rock Creek - Rocky Point area in Columbia County consists of massive to hummocky bedded sandstone with some bioturbated siltstone and coal formed in a delta front complex ranging from brackish-water swamps to storm-wave-dominated lower shoreface environments. Sandstone onlaps basement highs of Tillamook Volcanics (Nehalem arch), resulting in a complicated facies geometry with some intrabasinal basaltic detritus. Sedimentary structures, statistical grain size analysis, and lithofacies associations suggest that strong wave processes reworked the delta front sands during a transgression at the seaward edge of the system. Thickening-upward and shallowing-upward sequences record periods of westward deltaic progradation and increasing storm-wave energy. C & W gas reservoirs consist of well-sorted, friable, fine-grained arkose to lithic arkose. Sandstone reservoir porosity and permeability average 31% and 1200 md, respectively. Porosity is dominated by primary intergranular pores which have been reduced by (1) compaction of ductile grains, (2) formation of minor mixed-layer clay rim cement, sparry calcite cement and authigenic pyrite, and (3) late stage precipitation of plagioclase, K-feldspar, and quartz overgrowths. However, partial dissolution of plagiociase feldspar has created some secondary porosity. Although arkosic sandstones have high porosities and correspondingly high permeabilities, chioritic cement in volcaniclastic-rich sandstones significantly reduces permeability without concomitant reduction in porosity. The Cole Mountain basalt (informal) locally intnides and overlies the Cowlitz Formation. These basalts to basaltic andesites have calc-alkaline affinities and consist of hypabyssal sills, submarine lava flows, and local peperites which are lithologically, chemically, and petrographically distinct from the slightly older Tillamook Volcanics. The uppermost Narizian to Refugian (latest Eocene) Keasey Formation unconfonnably overlies the Cowlitz Formation in the study area. Volcanic and glauconitic sandstones at the base of the Keasey Formation mark the unconformity and reflect a period of slow sedimentation under slightly reducing conditions. The Keasey Formation predominantly consists of stractureless, tuffaceous fossiliferous mudstone deposited by hemipelagic sedimentation on the middle to upper slope. The informal Miocene (?) Ivy Creek formation locally disconformably overlies the Keasey Formation in the study area. The fluvially deposited Ivy Creek formation consists of a friable upper trough cross-bedded pebbly sand fades which overlies 9 m of blue organic-rich overbank clay. Local pebbly grits in matrix-support with buried flow-oriented rooted tree stems suggest that some debris flows entered the fluvial system from surrounding highlands. The unit may correspond to the middle Miocene Scappoose Formation. Northwest-trending down-to-the-northeast high-angle faults, some with oblique offset, and a subordinate set of older east-trending faults are the dominant structural features of the Rock Creek - Rocky Point area. The faulting produces a dissected structural high or upthrown basement block of middle to upper Eocene Tillamook Volcanics. Upper Eocene sedimentary units flank the north and south sides with occasional perched sedimentary outliers along the volcanic crest. Although source rock evaluations from this study indicate that the upper Eocene samples are thermally immature, it is possible that thermogenic thy gas at Mist migrated updip from more deeply buried Cowlitz shales and coals or equivalent Eocene strata in the adjacent Tualatin and Astoria basins.