This thesis investigates the influence of early diagenesis on trace metal and
molybdenum isotope behavior in marine and lacustrine environments. Chapter one is a
synthesis of previous research in all the marine environments investigated, providing an
essential geochemical context for interpreting the observed behavior of Mo in these settings.
Chapter...
Sediments of the central Chile margin record changes in ocean circulation and
continental erosion associated with large–scale climate change. Here Antarctic–
influenced Southern Ocean currents flow equatorward, forming a link between the high–
and low–latitude oceans. Part of this link, Antarctic Intermediate Water, is an important
conduit that ventilates South...
Ocean circulation is an important component in Earth's climate system. Predicting future climate and circulation changes requires an improved understanding of the past relationship between climate and ocean currents. The neodymium isotope composition (εNd) of water masses is frequently used as a quasi-conservative tracer to reconstruct ocean circulation. The current...
Large barite (BaSO4) structures mark cold seeps in the southern San Clemente Basin. Barium flux to San Clemente sediments is two to three times greater than fluxes measured in surrounding California Borderland basins. Analyses of sediment trap material, water column samples, sediments and pore water indicate that expected bariumbearing mineral...
The exchange of waters between the Pacific and the Southern Oceans occurs along the eastern boundary of the South Pacific. Because water masses of the Antarctic provide a connection among the world's ocean basins, these water masses maintain the ability to influence changes in ocean circulation and climate (Lynch-Stieglitz et...
This study is composed of two parts. Section I deals with
developed moorages and marinas--where they are; what services are
offered in each, and how well the existing supply of permanent moorages
serves the boating public. Section II examines the need for temporary
'harbors of refuge' in the area, what...
We present concentrations of germanium and silicon in sediment pore waters, basaltic formation fluids,
and bulk sediment from three ridge flank hydrothermal systems (RFHS). Basaltic formation fluids from
warm (>30°C) RFHS have much higher Ge concentrations and Ge:Si molar ratios than overlying sediment
pore waters, requiring seawater-basalt reactions to dominate...
Tillamook Bay is the second largest estuary on the Oregon coast, and concerns have been raised whether human induced impacts have been responsible for the perceived increase in sedimentation rates during the past century. Major land-use practices within the five watersheds of the Bay include logging, forest fires, the construction...
Subsurface hydrothermal activity dominates the heat and salt budgets of the deep water column in Crater Lake, Oregon. From a time series of conductivity-temperature-depth data and data from a thermistor chain mooring, we estimate that the net hydrothermal heat flow is ~1 W m⁻² and the corresponding salt flux is...
The investigation described in this project will test the hypothesis that fluxes of carbon, barium, manganese, iron and uranium associated with fluid seepage at the San Clemente fracture zone significantly affect the geochemical budgets for these elements, and ultimately result in anomalously high benthic fluxes throughout the San Clemente basin.
A meaningful application of Mo as a paleo-redox proxy requires an understanding of Mo cycling in modern reducing environments. Stagnant euxinic basins such as the Black Sea are generally regarded as model systems for understanding euxinic systems during early Earth history. However, drawing direct parallels between the Black Sea and...
As a result of the past three years of field studies and our interpretation of these and other data from the literature, we conclude that there are inputs of hydrothermal fluids into the bottom of Crater Lake. The dissolved materials associated with these thermally and chemically enriched fluids, coupled with...
This dissertation works towards determining the mechanisms driving the Mo isotopic composition of soils, and how these signals may be used to refine the use of Mo as a proxy of biogeochemical processes. The first step towards quantifying Mo fractionation in soils is to determine the mechanisms controlling Mo accumulation,...
A benthic microbial fuel cell (BMFC) is an electrochemical device that
generates current from the redox gradient at the sediment-water interface. Early
prototypes had anodes buried in anoxic sediments and cathodes in overlying water.
The BMFCs described in this dissertation are based on a chamber design that enables
the use...
This thesis presents the results of a formal evaluation of a new AOGCM, GENMOM, demonstrating its ability to simulate present-day climate and ENSO dynamics. The model is applied to simulate climate for the Last Glacial Maximum, deglacial, and Holocene time periods. The model output is evaluated against the best available...
Benthic incubation chambers have been deployed in a variety of geochemical environments that provide a comprehensive geochemical framework from which to address issues related to Ba geochemistry and the use of Ba as a paleoproxy. First order budgets for barium show that in the equatorial Pacific, present rates of Ba...
Flux estimates show that upward mixing of the deep-water nitrate pool accounts for more than 85% of the total new nitrogen input to the euphotic zone of Crater Lake. Because measured primary productivity (360 mg C m-2 d-1) is 10–30 times higher than a level supported solely by the input...
We present molybdenum isotope and concentration data from 14 sites in the eastern Pacific from the
central California to the Peru margin. The environments studied have been chosen to represent a broad
range in oxidation-reduction (redox) potential, which provide a framework for the behavior of this redox-sensitive
element. Manganese-rich hemipelagic...
We present a new estimate for the crustal phosphorous sink that results from reactions among seawater, basalt, and sediment blanketing low temperature mid-ocean ridge flank hydrothermal systems. New estimates for global hydrothermal power output, sediment thickness, and the dissolved phosphate concentrations in basement formation fluids indicate that fluid flow through...
Diatom remains indicate the oceanic Ge/Si ratio (μmol/mol) has varied temporally, ranging from Miocene values of 0.9 to Last Glacial Maximum (LGM) values of 0.55, with the present value of 0.69. These ratios lie between those for the primary sources for these elements: continental weathering (Ge/Si = 0.5) and hydrothermal...
The data presented in this report demonstrate significant improvements
in the ability to constrain trace element and Sr isotopic
concentrations in sediments overlying ridge-flank hydrothermal
systems. Improved sampling methods orchestrated by the Integrated
Ocean Drilling Program (i.e., advanced piston coring and
anoxic sample processing) enabled the collection of reactive pore...
Active inputs of thermally and chemically enriched fluids at the bottom of Crater Lake create small vertical and horizontal heterogeneities in the deep-lake temperature and salt distribution. Using an internally recording CTD and a precise definition for salinity as a function of in situ conductivity and temperature, we assess the...
On average, the water column of Lake Superior is undersaturated with respect to dissolved oxygen and supersaturated with respect to carbon dioxide during the summer-stratified period. On the basis of temporal changes in water column dissolved oxygen, we calculate rates of oxygen consumption that range from 0.19 to 0.75 mmol...
The ability to reconstruct past ocean currents is essential for determining ocean circulation’s role in global heat transport and climate change. Our understanding of the relationship between circulation and climate in the past allows us to predict the impact of future climate-driven circulation changes. One proposed tracer of past ocean...
We determined pore fluid rare earth element (REE) concentrations in near-surface sediments retrieved from the continental margin off Oregon and California (USA). These sites represent shelf-to-slope settings, which lie above, within, and below the oxygen minimum zone of the Northeast Pacific. The sediments are characterized by varying degrees of net...
Because ocean circulation impacts global heat transport, understanding the relationship between deep ocean circulation and climate is important for predicting the ocean's role in climate change. A common approach to reconstruct ocean circulation patterns employs the neodymium isotope compositions of authigenic phases recovered from marine sediments. In this approach, mild...
The rare earth elements (REEs) have been established as powerful tracers for a range of physiochemical processes occurring in the natural environment. They also hold significant economic importance as many technological advancements are reliant upon the REEs for their unique magnetic, luminescent, and electrochemical characteristics. In sedimentary settings, understanding the...
Small temporal and spatial variations in the distribution of dissolved oxygen in Crater Lake, Oregon, are used to estimate the mean age of the lake’s deep water, the flux of labile organic carbon to the deep lake, and the influence of hydrothermal activity on the concentration of dissolved oxygen within...
Isotopic analyses of dissolved molybdenum are presented for sediment pore waters from a reducing
sedimentary basin and for fluids from a low-temperature ridge flank hydrothermal system. δ⁹⁸/⁹⁵Mo in
these fluids range from 0.8 to 3.5%₀ (relative to a laboratory standard), demonstrating that marine
sedimentary reactions significantly fractionate Mo isotopes. Within...
We present evidence for pore water flow through the sediment of Crater Lake, Oregon based on systematic variations in pore water chemical compositions and thermal gradients. Pore water was extracted from sediment by centrifugation and diffusive exchange using a gravity corer deployed from a surface vessel and a box corer...
We examined the characteristics of biological patches at four different locations to assess the relationship of patch vertical scale, amplitude, and persistence. In contrast to patches of larger animals, we found that the majority of coherent aggregations of plankton at each site were vertically compressed, with most smaller than 5m...
This thesis investigates the behavior of major inorganic nutrients (P, N, Si), trace metals (Mn, Fe), and alkaline-earth metals (Ba) within Tillamook Bay over seasonal cycles and under a range of river discharge conditions from October 1997 through December 1999. Located in the Pacific Northwest region, Tillamook Bay is an...
The objective of this study was to compare two techniques for estimating benthic fluxes of nutrients (nitrate, phosphate, and silicic acid) and Ge/Si flux ratios. In situ flux chambers were deployed, and cores were collected and incubated at 9 sites along the California margin in July 2001. Both techniques were...
The isotopic composition of the dissolved inorganic carbon (DIC) collected at sites of active methane discharge on Hydrate Ridge, Oregon, reveals anaerobic methane oxidation mediated by bacteria, with δ13CDIC reaching values as low as –48‰ in the upper 4 cm of the sediment. In spite of the high sulfide levels...
Benthic chamber measurements of the reactants and products involved with biogenic matter diagenesis (oxygen, ammonium, nitrate, silicate, phosphate, TCO₂, alkalinity) were used to define fluxes of these solutes into and out of the sediments off southern and central California. Onshore to offshore transects indicate many similarities in benthic fluxes between...
Geophysical and biogeochemical processes associated with fluid venting from active and passive continental margins will receive significant scientific and economic attention
into the next century and are of major societal relevance. An important unknown among these interrelated processes is the role played by methane gas hydrates, at and below the...
A massive release of methane on the Cascadia Hydrate Ridge was documented
during a ROPOS program in August 1998, consistent with previously reported
observations in 1996. An extensive survey of the seafloor revealed that the
seeps lie within a narrow band trending 109 degrees. This feature parallels larger
mounds imaged...
A study was conducted to determine the heat transfer characteristics
of pin finned heat sinks in natural convection. Three pin
diameters were studied: 0.238 cm, 0.318 cm and 0.396 cm. The pins
were attached to the base in two arrangements, triangular and
rectangular, forming a horizontal array. Pin spacing was...
Cores taken from the ridge areas of the Gorda-Juan de Fuca
plate have a sedimentation rate that is appropriate for the study of
late Quaternary stratigraphy. An analysis of the clay and silt
mineralogy of the cores using X-ray diffraction methods and by
noting changes in the foraminiferan-radiolarian abundances in...
More Americans are participating in sport every year
and several organizations have made it their mission to
provide the opportunity for organized sport participation.
College and University intramural departments are one of
those organizations. They provide participation
opportunities on nearly every college campus. The review of
literature identifies the sociological...
Monocrotaline (MCT) is a member of a class of naturally occurring
phytotoxins known as pyrrolizidine alkaloids (PAs). Exposure to PAs can result
in liver and cardiopulmonary lesions as well as lymphoid organ atrophy. In the
present study C57BI/6 (B6) mice received MCT (0-150 mg/kg/day, po) for 14
days. Overt toxicity...
In the summer of 2001 the Oregon Coast Aquarium opened a new exhibit on sharks entitled, "Great White Mystery: What Happened to Surfer Bob?" For the purposes of this study, a survey was designed to determine whether visitors to the new exhibit learned factual information or left with changed attitudes...
The mycosporins, formerly called P310's are secondary metabolites
of fungi closely associated with fungal reproductive processes that
require light. The structurally related iminomycosporins are found in
marine plants and animals and may also have functions related to
light. In this study, approaches toward the asymmetric synthesis of
the mycosporins are...
In vivo research following ingesting of commercially available
Lactobacillus tablets, which contain about 2X10⁶ cfu/tablet of
Lactobacillus acidophilus and Lactobacillus bulgaricus cells in a dose
of four tablets daily, showed serum lipoprotein concentrations did not
change significantly. In order to increase the number of viable
Lactobacillus bacteria after challenging in...
Jets in crossflow are used in a wide range of engineering applications and have been studied for more than 60 years. The transversal penetration and structure of a jet placed in a crossflow is known to be strongly three-dimensional. It is believed that, by using a pulsed jet inclined in...
A personal view of the 50 years of broadcasting - radio and ETV - that we call KOAC, Corvallis. Service to people of Oregon from 1922 through 1972 with program philosophies, historical evolution of facilities - and the people who kept is all happening ......
To investigate the responses of healthy adult women to two
levels of vitamin B-6, a seven week two-part experiment was conducted
with five young adults and eight middle-aged subjects. During the
four unsupplemented weeks, dietary vitamin B-6 was 2.3-2.4 mg/day.
In the final three weeks, the same diet was supplemented...
New ice cores retrieved from the Taylor Glacier (Antarctica) blue ice area contain ice and air spanning the Marine Isotope Stage (MIS) 5/4 transition, a period of global cooling and ice sheet expansion. Chronologies were determined for the ice and air bubbles in the new ice cores by visually matching...
Trained male cyclists (6 in study 1, 5 in study 2) cycled to exhaustion (EXH) at
75% of VO₂ max twice; once in the non-supplemented (NS) state and once in the vitamin
B-6 (B-6)(20 mg PN) supplemented (S) state. The diet contained 2.3 mg B-6 in study 1
and 1.9...
Marine primary production can be modeled and estimated using remotely-observable physiological signatures such as chlorophyll and carbon. Current models are based on strict physiological relationships based on photoautotrophic phytoplankton, and discrepancies between modeled and in situ data may stem from unaccounted-for physiological deviations from photoautotrophy. Mixotrophic phytoplankton can obtain energy...
The recent establishment of the Galápagos Marine Reserve (GMR) presents a unique opportunity to analyze the economic implications of using zonification as a tool to manage conflicting claims to a fragile and limited resource. Recognizing that the long-term success of the GMR depends on the cooperation of all of the...
The effect of jet flow pulsing and blowing ratio on a jet in cross flow has been investigated. Preliminary jet flow studies were performed without cross flow and an extensive study of jet with cross flow was done for a total of nine test cases. The effect of velocities ratios...
Kinetics of cell division in the intestinal epithelial proliferative cells (cell nests) of the rough-skinned newt, Taricha granulosa, were studied using tritiated thymidine autoradiography and the mitotic arresting properties of colcemid. Percent labeled mitoses (PLM) curves were drawn from the autoradiographic data from two separate experiments in which the newts...
Deciphering the evolution of global climate from the end of the Last Glacial Maximum approximately 19 ka to the early Holocene 11 ka presents an outstanding opportunity for understanding the transient response of Earth's climate system to external and internal forcings. During this interval of global warming, the decay of...
Long-term, large-scale studies of meta-ecosystems provide critical information about how global change influences communities. In my dissertation, I analyzed data from studies encompassing 18 years (2006 – 2023) and over 1,000 km of coastline to investigate drivers of rocky intertidal community structure and dynamics. Specifically, I explored the roles of...
Five simulated precipitation patterns characteristic of the Columbia
Basin and Plateau region and six fertilization rates were evaluated
for their effect on percent crude protein, percent in vitro dry matter
digestibility, fiber content, and yield of wheat aftermath on a commercial
farm in north central Oregon.
The higher moisture regimes...
Determination of the source and fate of natural (higher plant lipids, marine
lipids, etc.) and anthropogenically (e.g., petroleum, coal emissions) derived
hydrocarbons and oxygenated compounds in the environment was accomplished
using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS)
to characterize or identify molecular biomarkers to be utilized as tracers....
Vertical transports of plankton, momentum, heat, and turbulence are modeled. A novel integration of high resolution turbulence and biophysical modeling is used to show the influence of a Kelvin-Helmholtz instability on the vertical migration of simple gyrotactic organisms. A viscous limit on mixing driven by shear turbulence is proposed. Large...
Three experiments were conducted (1) to develop and characterize
polyclonal antibodies against ovine adipocyte plasma membranes (APM),
(2) to evaluate the effect of administering the developed antibodies to
lambs on lamb growth and carcass characteristics, and (3) to investigate
the possibility of using the developed antibodies to identify antigenic
components...
Anthropogenic activities have posed many threats to the oceans and marine life. Understanding how individuals are affected and physiologically respond to these threats is crucial and allows for management and conservation applications. I evaluated the overall health condition of a subpopulation of gray whales (Eschrichtius robustus) along the Oregon coast,...
Oregon's Columbia River ports are as diversified as the lands on which they are located. From Astoria to Umatilla, the common factor that links the ports is the Columbia River, which borders all of the ports discussed in this publication.
The progress report that follows includes research results ranging from unproved ideas to scientific papers published during the tenure of this contract, The end of the contract year finds several facets of our work in various states of preparation, therefore the reader is cautioned that all except the published papers...
Concurrent satellite-measured chlorophyll (CHL), sea surface temperature (SST), sea level anomaly (SLA) and model-derived wind vectors from the 13+ year SeaWiFS period September 1997 – December 2010 quantify time and space patterns of phytoplankton variability and its links to physical forcing in the Pacific Ocean. The CHL fields are a...
Baleen whales store energy gained on foraging grounds to support reproduction and other metabolic needs while fasting for long periods during migration. Whale body condition can be used to monitor foraging success, and thus better understand and anticipate individual‐ and population‐level trends in reproduction and survival. We assessed the body...
Using data collected from cannabis growers and traditional farmers, and the “Good Farmer” approach, this research provides a comparative analysis of the occupational identities of cannabis cultivators and traditional farmers in Colorado and Oregon. Though both growers and farmers within the study suggested that cannabis cultivation differed from conventional agriculture,...
Mycotoxins are food-borne toxins produced by molds which are commonly found on animal feeds of economic significance. Toxic doses of these compounds vary widely across livestock species, and even within a species when considered across all stages of development and production. This variation is due to the wide range of...
Quantification and comparison of morphological changes over the last ~300 y in Oregon salt marshes provide valuable insights into the tectonic, hydroclimatic, and anthropogenic processes shaping this important intertidal zone. Understanding of the rates and drivers of salt marsh change contextualizes intertidal habitats within the sediment routing system (i.e., source...
A study was conducted over a two year period, 1973 through
1974, on perennial ryegrass-subclover pastures with stocking rates
of 7.4 (moderate), 9. 9 (heavy), and 12.4 (overstocked) ewes per
hectare to establish guidelines on stocking intensity for dryland
improved pastures in western Oregon. Climatic conditions varied
annually and caused...
Fishery management production models tend to stress only the elements directly linked to fish (i.e. fish, fish food, and fish predators). Large coastal jellyfish are major consumers of plankton in heavily fished ecosystems; yet, they are frequently not included as model components. We explore the relationship between gulf menhaden (Brevoortia...
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Fisheries Hokkaido University, 21: 2‐
112.
James, M. C., Scott, A. S.‐M., and Ransom, A. M. 2007
End-to-end models were constructed to examine and compare the trophic structure and energy flow in coastal shelf ecosystems of four US Global Ocean Ecosystem Dynamics (GLOBEC) study regions: the Northern California Current, the Central Gulf of Alaska, Georges Bank, and the Southwestern Antarctic Peninsula. High-quality data collected on system components...
Fishery management production models tend to stress only the elements directly linked to fish (i.e. fish, fish food, and fish predators). Large coastal jellyfish are major consumers of plankton in heavily fished ecosystems; yet, they are frequently not included as model components. We explore the relationship between gulf menhaden (Brevoortia...
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Jul-Aug 2003-2004,2006-2008, 2010-2011 Mike Roman and James Pierson (University of Maryland
Satellite-derived data provide the temporal means and seasonal and nonseasonal
variability of four physical and biological parameters off Oregon and Washington
(41°–48.5°N). Eight years of data (1998–2005) are available for surface chlorophyll
concentrations, sea surface temperature (SST), and sea surface height, while six years of
data (2000–2005) are available for...
This dissertation concentrates on the controlling factors on the instability of the Laurentide Ice Sheet (LIS) and their effects on abrupt climate change. Northern Hemisphere climate fluctuated abruptly during the last deglaciation possibly related to variability in Atlantic meridional overturning circulation (AMOC) and reduced aerial extent of the LIS. Reductions...
Greenland ice core water isotopic composition (δ¹⁸O) provides detailed evidence for abrupt climate changes, but is by itself insufficient for quantitative reconstruction of past temperatures and their spatial patterns. We investigate Greenland temperature evolution during the last deglaciation using independent reconstructions from three ice cores and simulations with a coupled...
The cause of warming in the Southern Hemisphere during the most recent deglaciation remains a matter of debate[superscript 1,2]. Hypotheses for a Northern Hemisphere trigger, through oceanic redistributions of heat, are based in part on the abrupt onset of warming seen in East Antarctic ice cores and dated to 18,000...
The distribution of barite (BaSO₄) in marine sediments has long been studied as a proxy for paleoproductivity. While pure barite is known to be a stable mineral in oxic sediments, it is also known that variations in the Sr/Ba ratio influence its solubility and liability during early diagenesis. To extract...
Ocean circulation is an important component in Earth's climate system. Predicting future climate and circulation changes requires an improved understanding of the past relationship between climate and ocean currents. The neodymium isotope composition (εNd) of water masses is frequently used as a quasi-conservative tracer to reconstruct ocean circulation. The current...
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Brian A. Haley, JamesMcManus
Ocean circulation is
The heart rate, oxygen consumption, survivorship, and 1-lactate
accumulation were determined in the intertidal limpets Collisella pelta
and Collisella digitalis in relation to laboratory desiccation at 15°C
or 30°C. Water loss was computed as a percentage of total initial body
water (wet weight - dry weight). Although water was lost...
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30 Comparison of McManus', Federizon's and Jamir's Site
Group Categories In Relation to Habitat
Continental margin sediments have been recognized as a major source of dissolved iron to the global ocean. The focus of this study was to build an early diagenetic model that can be used to simulate iron fluxes from continental margins and thereby identify key controlling factors. The model uses the...
When characterizing the processes that shape ecosystems, ecologists increasingly use the unique perspective
offered by repeat observations of remotely sensed imagery. However, the concept of change embodied in much of
the traditional remote-sensing literature was primarily limited to capturing large or extreme changes occurring
in natural systems, omitting many more...
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Sen13, Todd A Schroeder7, Annemarie Schneider14,
Ruth Sonnenschein15, James E Vogelmann16, Michael A
This study deals with the histochemical identification of the
changing patterns of glycogen in the uterus of the early pregnant and
lactating golden hamster (Mesocricetus auratus Waterhouse). The uterus of the hamster representing days one through five of gestation,
and one through ten, twelve, and fourteen of lactation, provided the...
This histochemical study deals with the changing patterns of
glycogen in the uterus of the immature virgin, cycling virgin, and
post partum (non-lactating) golden hamster (Mesocricetus auratus
Waterhouse). The periodic acid-Schiff technique was used for the
histochemical localization of glycogen in the uterus of the immature,
cycling and non-lactating post...
This thesis describes the development of a rare earth element (REE) proxy for paleoceanographic studies of climate change. This work was done in three stages with the goal: (1) To develop a cleaning method that overcomes the problems of REE readsorption; (2) To measure pore water REEs for evaluation of...
Oregon Biography Index is intended to serve primarily as a starting point in locating biographies of Oregonians. We have indexed 47 historical volumes which are either entirely devoted to biographies or have large self-contained biographical sections. The profiles in the books vary widely in accuracy and detail. Birth dates of...