Mechanical vibrations compromise the integrity of key components of thermal power plants. Without careful design, strong resonances during steady state operation can wear these components to the point of failure, leading to an unsafe situation that may force a plant to shut down. The purpose of this research is to...
At global and regional scales, tree mortality rates are positively correlated with forest net primary productivity (NPP). Yet causes of the correlation are unknown, in spite of potentially profound implications for our understanding of environmental controls of forest structure and dynamics and, more generally, our understanding of broad-scale environmental controls...
Five ruminally cannulated steers (initial BW=464 ± 26 kg) consuming low-quality forage (5% CP; 78% NDF; DM basis) were used in an incomplete 5 x 4 Latin square with four 18-d periods to determine the influence of supplemental N source and supplementation frequency (SF) on ruminal fermentation dynamics. Treatments, arranged...
• A technique for measuring in vitro respiration was investigated to understand why rates were higher than those reported in vivo and to elucidate trends within mature Pseudotsuga menziesii (Douglas‐fir) trees.
• Extracted increment cores were divided into 3–4 radial depths and a gas chromatograph was used to compare respiration...
It has been suggested that thinning trees and other fuel-reduction practices aimed at reducing the probability
of high-severity forest fire are consistent with efforts to keep carbon (C) sequestered in terrestrial pools, and
that such practices should therefore be rewarded rather than penalized in C-accounting schemes. By evaluating how fuel...
The methods for conducting reductionist ecological science are well known and widely used. In contrast, those used in the synthesis of ecological science (i.e., synthesis science) are still being developed, vary widely, and often lack the rigor of reductionist approaches. This is unfortunate because the synthesis of ecological parts into...
Litter nutrient dynamics contribute significantly to biogeochemical cycling in forest ecosystems. We examined how site environment and initial substrate quality influence decomposition and nitrogen (N) dynamics of multiple litter types. A 2.5-year decomposition study was installed in the Oregon Coast Range and West Cascades using ¹⁵N-labeled litter from Acer macrophyllum,...
Disturbance processes of various types substantially modify ecosystem carbon dynamics both temporally and spatially, and constitute a fundamental part of larger landscape-level dynamics. Forests typically lose carbon for several years to several decades following severe disturbance, but our understanding of the duration and dynamics of post-disturbance forest carbon fluxes remains...
Even slight terrain inhomogeneities can cause large horizontal variations in the clear, stably stratified, nocturnal boundary layer largely through cold air drainage. By early morning the valleys and depressions can be several degrees cooler than the adjacent slopes and plateaus. As surface heating begins in the morning, these horizontal variations...
Motivated by satellite altimeter observations of enhanced sea level variability near steep topographic slopes in the Southern Ocean, effects of topography on the spatial distribution of mesoscale eddies and on eddy–mean flow interaction are investigated using a two-layer, wind-forced, quasigeostrophic channel model. The principal topography, a zonal ridge with a...
A series of satellite sea surface temperature (SST) intercomparison workshops were conducted under NASA sponsorship at the Jet Propulsion Laboratory. Three different satellite data sets were compared with each other, with routinely collected ship data, and with climatology for the months of November 1979, December 1981, March 1982, and July...
Severe droughts occurred in the western United States during recent decades, and continued human greenhouse gas emissions are expected to exacerbate warming and drying in this region. We investigated the role of water availability in shaping forest carbon cycling and morphological traits in the eastern Cascade Mountains, Oregon, focusing on...
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steep
climatic gradient in the Cascade Mountains, Oregon
L. T. Berner and B. E. Law
Correspondence
Severe droughts occurred in the western United States during recent decades, and continued human greenhouse gas emissions are expected to exacerbate warming and drying in this region. We investigated the role of water availability in shaping forest carbon cycling and morphological traits in the eastern Cascade Mountains, Oregon, focusing on...
Full Text:
, Oregon
Berner, L. T., & Law, B. E. (2015). Water limitations on forest carbon cycling and
conifer
Severe droughts occurred in the western United States during recent decades, and continued human greenhouse gas emissions are expected to exacerbate warming and drying in this region. We investigated the role of water availability in shaping forest carbon cycling and morphological traits in the eastern Cascade Mountains, Oregon, focusing on...
Severe droughts occurred in the western United States during recent decades, and continued human greenhouse gas emissions are expected to exacerbate warming and drying in this region. We investigated the role of water availability in shaping forest carbon cycling and morphological traits in the eastern Cascade Mountains, Oregon, focusing on...
Full Text:
, Oregon
Berner, L. T., & Law, B. E. (2015). Water limitations on forest carbon cycling and
conifer
Severe droughts occurred in the western United States during recent decades, and continued human greenhouse gas emissions are expected to exacerbate warming and drying in this region. We investigated the role of water availability in shaping forest carbon cycling and morphological traits in the eastern Cascade Mountains, Oregon, focusing on...
Severe droughts occurred in the western United States during recent decades, and continued human greenhouse gas emissions are expected to exacerbate warming and drying in this region. We investigated the role of water availability in shaping forest carbon cycling and morphological traits in the eastern Cascade Mountains, Oregon, focusing on...
Observations of Earth’s magnetic field extending back to 3.45 billion years ago indicate that generation by a core dynamo must be sustained over most of Earth’s history. However, recent estimates of thermal and electrical conductivity of liquid iron at core conditions from mineral physics experiments indicate that adiabatic heat flux...
Changing environmental conditions in the North Pacific are altering the lipid/fatty acid (FA) composition of zooplankton assemblages, but the consequences to resident fish larvae are unknown. In the laboratory, we reared Pacific cod Gadus macrocephalus larvae over 4 wk on prey enriched with varying levels of 2 essential FAs (docosahexaenoic...
Management in fire-prone ecosystems relies widely upon application of prescribed fire and/or fire surrogate (e.g., forest thinning) treatments to maintain biodiversity and ecosystem function. Recently, published literature examining wildlife response to fire and fire management has increased rapidly. However, none of this literature has been synthesized quantitatively, precluding assessment of...
Juvenile red hake Urophycis chuss were collected while they were inhabiting sea scallops Placopecten magellanicus , and the effects of appetite and food availability on prey consumption and growth were examined under laboratory conditions. Fish took increasing amounts of live amphipods Gammarus annulatus with increasing periods of food deprivation up...
The sea-state bias in Geosat altimeter range measurements expressed as a percentage of significant
wave height (SWH) is examined as a function of SWH. The bias is shown to be approximately
a fixed -3.5% of SWH for SWH smaller than about 4 m. For larger SWH, the bias decreases in...
A Geosat altimeter wind speed algorithm is derived by cross-calibrating Geosat and Seasat
altimeter estimates of the normalized radar cross section σ₀ and modifying an existing Seasat
altimeter wind speed model function to obtain a model function appropriate for Geosat observations.
It is argued that the σ₀ distribution measured by...
In order to understand what controls the composition of suspended particulate material (SPM) in estuarine turbidity maxima (ETM), a set of SPM samples collected in the Columbia River and estuary (northwestern USA) during 3 seasons (fall 1990, summer 1991, spring 1992) was analyzed for detrital mineral (Min), total organic matter...
A trophic model that simulates interactions between
a predatory fish (Pacific hake, Merluccius productus), forage
fish, and juvenile salmon off the Columbia River
was constructed to identify if trophic interactions could
account for marine mortality of Columbia River juvenile
salmon. The model estimates the number of juvenile
salmon that are...
Addressing the ongoing decline of Pacific Lamprey Entosphenus tridentatus across its range along the west coast
of North America requires an understanding of all life history phases. Currently, spawning surveys (redd counts)
are a common tool used to monitor returning adult salmonids, but the methods are in their infancy for...
Distinct aggregations of fungal hyphae and rhizomorphs, or "mats", formed by some genera of ectomycorrhizal (EcM) fungi are common features of soils in coniferous forests of the Pacific Northwest. We measured in situ respiration rates of Piloderma mats and neighboring non-mat soils in an old-growth Douglas-fir forest in western Oregon...
These are the proceedings of the fifth short course in managing young forests in the Douglas-fir region, conducted by the School of Forestry, Oregon State University, June 11-13, 1973.
Knowledge and experience in the management of young forests continues to expand. The short courses are designed to keep pace with...
The fisheries sectorof Sri Lanka means of livelihoodfor 2.6 million peopleand the vast majority of themare involved in small scale fisheries. The study was taken up with the objectivesof to identify social &political membership status of small scale fishery value chain members, to assess the level of decision making power...
Background. Ampelisca eschrichtii Krøyer, 1842 of the Sakhalin Shelf of the Okhotsk Sea, Far Eastern Russia, comprise the highest known biomass concentration of any amphipod population in the world and are a critically important prey source for western gray whales. Growth and reproduction in this population has not been apparent...
Background. Ampelisca eschrichtii Krøyer, 1842 of the Sakhalin Shelf of the Okhotsk Sea, Far Eastern Russia, comprise the highest known biomass concentration of any amphipod population in the world and are a critically important prey source for western gray whales. Growth and reproduction in this population has not been apparent...
Ecological effects of populations of the salp Cyclosalpa bakeri were studied in late summer of 1984, 1987 and 1988 dunng the Subarctic Pacific Ecosystem Research Station P in the northeast Pacific. Salps occurred largely in the top 60 m, with from 76 to 3621 mg C m⁻². Three approaches were...
Statistics of central tendency and dispersion may
not capture relevant or desired characteristics of the distribution
of continuous phenomena and, thus, they may not
adequately describe temporal patterns of change. Here, we
present two methodological approaches that can help to identify
temporal changes in environmental regimes. First, we
use higher-order...
Statistics of central tendency and dispersion may
not capture relevant or desired characteristics of the distribution
of continuous phenomena and, thus, they may not
adequately describe temporal patterns of change. Here, we
present two methodological approaches that can help to identify
temporal changes in environmental regimes. First, we
use higher-order...
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environmental data
Arismendi, I., Johnson, S. L., & Dunham, J. B. (2015). Technical Note:
Higher-order
Worldwide, lack of data on stream temperature has motivated the use of regression-based
statistical models to predict stream temperatures based on more widely available data on air
temperatures. Such models have been widely applied to project responses of stream temperatures
under climate change, but the performance of these models has...
Worldwide, lack of data on stream temperature has motivated the use of regression-based
statistical models to predict stream temperatures based on more widely available data on air
temperatures. Such models have been widely applied to project responses of stream temperatures
under climate change, but the performance of these models has...
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change on
stream temperature?
Arismendi, I., Safeeq, M., Dunham, J. B., & Johnson, S. L. (2014). Can
Piscivory by birds can be significant, particularly on fish in small streams and during seasonal low flow when available cover from predators can be limited. Yet, how varying amounts of cover may change the extent of predation mortality from avian predators on fish is not clear. We evaluated size-selective survival...
Dynamics of dead wood, a key component of forest structure, are not well described for mixed-severity fire regimes with widely varying fire intervals. A prominent form of such variation is when two stand-replacing fires occur in rapid succession, commonly termed an early-seral “reburn.” These events are thought to strongly influence...
A key uncertainty concerning the effect of wildfire on carbon dynamics is the rate at which fire-killed biomass (e.g., dead trees) decays and emits carbon to the atmosphere. We used a ground-based approach to compute decomposition of forest biomass killed, but not combusted, in the Biscuit Fire of 2002, an...
Previous research has suggested that the use of more authentic learning activities can produce more robust and durable knowledge gains. This is consistent with calls within civil engineering education, specifically hydrology, that suggest that curricula should more often include professional perspective and data analysis skills to better develop the ‘T-shaped’...
The lower Deschutes River of northcentral Oregon has a historically uniform discharge record. Significant reductions in discharge below the seasonal norms will degrade the environment for migratory and resident salmonids by increasing siltation and gravel compaction, and by reducing intragravel water dissolved oxygen content. Fish spawning will be limited by...
Statistics of central tendency and dispersion may not capture relevant or desired characteristics of the distribution of continuous phenomena and, thus, they may not adequately describe temporal patterns of change. Here, we present two methodological approaches that can help to identify temporal changes in environmental regimes. First, we use higher-order...
Worldwide, lack of data on stream temperature has motivated the use of regression-based statistical models to predict stream temperatures based on more widely available data on air temperatures. Such models have been widely applied to project responses of stream temperatures under climate change, but the performance of these models has...
Dendrimers are well-defined, polymeric nanomaterials currently being investigated for biomedical applications such as medical imaging, gene therapy, and tissue targeted therapy. Initially, higher generation (size) dendrimers were of interest because of their drug carrying capacity. However, increased generation was associated with increased toxicity. The majority of studies exploring dendrimer toxicity...
1. Temperature is a major driver of ecological processes in stream ecosystems, yet the dynamics of
thermal regimes remain poorly described. Most work has focused on relatively simple descriptors
that fail to capture the full range of conditions that characterise thermal regimes of streams across
seasons or throughout the year....
Climate-induced changes may be more substantial within the marine environment, where following ecological change is logistically difficult, and typically expensive. As marine animals tend to produce stereotyped, long-range signals, they are ideal for repeatable surveying. In this study we illustrate the potential for calling rates to be used as a...
Russet Burbank, Russet Norkotah, and Shepody tubers infected with Potato virus Y strains (PVYO, PVYN:O, PVYNTN) were tested from storage at 4A degrees C at the initiation of sprouting and then the same tubers were tested again from storage at 4A degrees C seventy eight days later. Samples were taken...
The International Food Policy Research Institute (IFPRI) and the International Center for Living Aquatic Resources Management (ICLARM), in collaboration with the Food and Agricultural Organization of the United Nations (FAO), are presently attempting to model supply and demand for highly aggregated fish categories within the context of IFPRI's IMPACT global...
The relationship between predator avoidance deficits induced by a simple handling stress and the level of plasma corticosteroids was determined for juvenile coho salmon Oncorhynchus kisutch. Groups of fish were held out of water for 1 min, then allowed to recover from this stress for 1, 90, or 240 min....
Phytoplankton biomass in high-nitrate, low-chlorophyll (HNLC) ocean regions exhibits a pronounced stability: variation occurs only within a narrow range of values. The magnitude of this variation has profound ecological and geochemical consequences. While mechanisms believed to set the upper limits to HNLC phytoplankton biomass (iron limitation, microherbivore grazing) have received...
To consider the regional scale effects of forest management requires complete and consistent data over large areas. We used Landsat Thematic Mapper and Multispectral Scanner (TM and MSS) imagery to map forest cover and detect major disturbances between 1975 and 1992 for a 4.2 x 106 ha area of interior...
Published June 1967. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The fisheries sector of Sri Lanka means of livelihood for 2.6 million people and the vast majority of them are involved in small scale fisheries. The study was taken up with the objectives of to identify social &political membership status of small scale fishery value chain members, to assess the...
Iron (Fe) and copper (Cu) are essential cofactors for microbial metalloenzymes, but little is known about the metalloenyzme inventory of anaerobic marine microbial communities despite their importance to the nitrogen cycle. We compared dissolved O₂ , NO₃⁻, NO₂⁻, Fe and Cu concentrations with nucleic acid sequences encoding Fe and Cu-binding...
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J.
Giovannonig, Kevin L. Verging, Frank J. Stewarta,b
*Correspondence: Corresponding Author
Iron (Fe) and copper (Cu) are essential cofactors for microbial metalloenzymes, but little is known about the metalloenyzme inventory of anaerobic marine microbial communities despite their importance to the nitrogen cycle. We compared dissolved O₂ , NO₃⁻, NO₂⁻, Fe and Cu concentrations with nucleic acid sequences encoding Fe and Cu-binding...
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reaction center, L and M subunits 81482 0 0 0 629 122 12 10 6 170 6 11 0
f.21.1.2 Cytochrome b of
Iron (Fe) and copper (Cu) are essential cofactors for microbial metalloenzymes, but little is known about the metalloenyzme inventory of anaerobic marine microbial communities despite their importance to the nitrogen cycle. We compared dissolved O₂ , NO₃⁻, NO₂⁻, Fe and Cu concentrations with nucleic acid sequences encoding Fe and Cu-binding...
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marine
oxygen minimum zones
Glass, J. B., Kretz, C. B., Ganesh, S., Ranjan, P., Seston, S. L., Buck, K
Chilodontidae is a small family of eight described characiform species popularly
known as headstanders. These small to moderately sized fishes are well known to
aquarists, who prize their striking spotted pigmentation and unusual behaviors, and to
systematists, who have revised both chilodontid genera in recent memory and studied
their phylogenetic...
We used serology and muscle digestion to test black bears (Ursus americanus) from western Oregon, USA, for Trichinella. Results indicate black bears in Oregon are not part of a sylvatic cycle for Trichinella, and risk of human exposure to Trichinella larvae from eating black bear meat from Oregon appears low.
Volcanic samples collected with the Monterey Bay Aquarium Research Institute's ROV Tiburon from eight seamounts at the continental margin offshore central to southern California comprise a diverse suite of mainly alkalic basalt to trachyte but also include rare tholeiitic basalt and basanite. All samples experienced complex crystal fractionation probably near...
Abstract: Background: The cross section for forming a heavy evaporation residue in fusion reactions depends on the capture cross section, the fusion probability, P[subscript CN], i.e., the probability that the projectile-target system will evolve inside the fission saddle point to form a completely fused system rather than reseparating (quasifission), and...
A period of cooling about 13,000 years ago interrupted about 2,000 years of deglacial warming. Known as the Younger Dryas (YD), the event is thought to have resulted from a slowdown of the Atlantic meridional overturning circulation in response to a sudden flood of Laurentide Ice Sheet meltwater that reached...