Tree mortality is an important demographic process and primary driver of forest dynamics, yet there are relatively few plot-based studies that explicitly quantify mortality and compare the relative contribution of endogenous and exogenous disturbances at regional scales. We used repeated observations on 289,390 trees in 3673 1 ha plots on...
Despite its importance to biodiversity and ecosystem function, patterns and drivers of regional scale variation in forest structure and development are poorly understood. We characterize structural variation, create a hierarchical classification of forest structure, and develop an empirically based framework for conceptualizing structural development from 11,091 plots across 25 million...
We characterized the structure and composition of unmanaged riparian forests in three river basins in Oregon’s coastal mountains. Our objective was to evaluate stand attributes at three spatial scales: streamside (site), drainage network (stream order), and basin (subregion). Data on basal area, species composition, snag density, canopy cover, and tree...
Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors...
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dominant trends are an
increase in minimum temperatures and a decrease in snow fall, while date of last
Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors...
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, Oregon USA). LiDAR was collected approximately 2000 m
above ground level by a fixed wing aircraft
Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors...
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, microtopographic, and overstory
canopy controls of tree invasion in a subalpine meadow
landscape, Oregon Cascades
Early‐seral ecosystems make important contributions to regional biodiversity by supporting high abundance and diversity of many plant and animal species that are otherwise rare or absent from closed‐canopy forests. Therefore, the period of post‐fire tree establishment is a key stage in forest stand and ecosystem development that can be viewed...
Twentieth-century land management has altered the structure and composition of mixed-conifer forests and decreased their resilience to fire, drought, and insects in many parts of the Interior West. These forests occur across a wide range of environmental settings and historical disturbance regimes, so their response to land management is likely...
Forests dominated by Douglas-fir and western hemlock in the Pacific Northwest of the United States have strongly influenced concepts and policy concerning old-growth forest conservation. Despite the attention to their old-growth characteristics, a tendency remains to view their disturbance ecology in relatively simple terms, emphasizing infrequent, stand-replacing (SR) fire and...
Forest ecosystem dynamics emerges from nonlinear interactions between adaptive biotic agents (i.e., individual trees) and their relationship with a spatially and temporally heterogeneous abiotic environment. Understanding and predicting the dynamics resulting from these complex interactions is crucial for the sustainable stewardship of ecosystems, particularly in the context of rapidly changing...
Canopy gaps created by tree mortality can affect the speed and trajectory of vegetation growth, species’ population dynamics, and spatial heterogeneity in mature forests. Most studies focus on plant development within gaps, yet gaps also affect the mortality and growth of surrounding trees, which influence shading and root encroachment into...
Forests play a critical role sequestering atmospheric carbon dioxide, partially offsetting greenhouse gas emissions, and thereby mitigating climate change. Forest management, natural disturbances, and the fate of carbon in wood products strongly influence carbon sequestration and emissions in the forest sector. Government policies, carbon offset and trading programs, and sustainable...
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Carbon Calculators: A Review for Managers,
Policymakers, and Educators” (Zald et al.)
Table S1
Forests play a critical role sequestering atmospheric carbon dioxide, partially offsetting greenhouse gas emissions, and thereby mitigating climate change. Forest management, natural disturbances, and the fate of carbon in wood products strongly influence carbon sequestration and emissions in the forest sector. Government policies, carbon offset and trading programs, and sustainable...
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biomass, carbon & bioenergy
Forest Carbon Calculators: A
Forests play a critical role sequestering atmospheric carbon dioxide, partially offsetting greenhouse gas emissions, and thereby mitigating climate change. Forest management, natural disturbances, and the fate of carbon in wood products strongly influence carbon sequestration and emissions in the forest sector. Government policies, carbon offset and trading programs, and sustainable...
Forest ecosystems are the most important terrestrial carbon (C) storage globally, and presently mitigate anthropogenic climate change by acting as a large and persistent sink for atmospheric CO₂. Yet, forest C density varies greatly in space, both globally and at stand and landscape levels. Understanding the multi-scale drivers of this...
Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors...
We studied the ages and diameter growth rates of trees in former Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) old-growth stands on 10 sites and compared them with young-growth stands (50-70 years old, regenerated after timber harvest) in the Coast Range of western Oregon. The diameters and diameter growth rates for the...
Disasters result from hazards affecting vulnerable people. Most disasters research by anthropologists focuses on vulnerability; this article focuses on natural hazards. We use the case of wildfire mitigation on United States Forest Service lands in the northwestern United States to examine social, political, and economic variables at multiple scales that...
Forest carbon (C) density varies tremendously across space due to the inherent heterogeneity of forest ecosystems. Variation of forest C density is especially pronounced in mountainous terrain, where environmental gradients are compressed and vary at multiple spatial scales. Additionally, the influence of environmental gradients may vary with forest age and...
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histograms (gray bars) for each variable, below diagonal each panel is a
scatterplot (gray circles) and fit
Forest carbon (C) density varies tremendously across space due to the inherent heterogeneity of forest ecosystems. Variation of forest C density is especially pronounced in mountainous terrain, where environmental gradients are compressed and vary at multiple spatial scales. Additionally, the influence of environmental gradients may vary with forest age and...
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a,⇑, Thomas A. Spies b, Rupert Seidl c, Robert J. Pabst a, Keith A. Olsen a, E. Ashley Steel d
Forest carbon (C) density varies tremendously across space due to the inherent heterogeneity of forest ecosystems. Variation of forest C density is especially pronounced in mountainous terrain, where environmental gradients are compressed and vary at multiple spatial scales. Additionally, the influence of environmental gradients may vary with forest age and...
The Northwest Forest Plan (NWFP) initiated one of the most sweeping changes to forest management in the world, affecting 10 million hectares of federal land. The NWFP is a science-based plan incorporating monitoring and adaptive management and provides a unique opportunity to evaluate the influence of policy. We used >25...
Equations for predicting height from diameter outside bark at breast height (DBH) were generated for 24 tree species in western Oregon. The equations were based on the asymptotic Chapman-Richards function. Because geographic location and site productivity may influence height-diameter relationships, height-diameter measures from 8727 plots were first grouped by site...
Forest policymakers and managers have long sought ways to evaluate the capability of forest landscapes to jointly produce timber, habitat, and other ecosystem services in response to forest management. Currently, carbon is of particular interest as policies for increasing carbon storage on federal lands are being proposed. However, a challenge...
Fire-prone landscapes are not well studied as coupled human and natural systems (CHANS) and present many challenges
for understanding and promoting adaptive behaviors and institutions. Here, we explore how heterogeneity, feedbacks, and external
drivers in this type of natural hazard system can lead to complexity and can limit the development...
Increasingly, objectives for forests with moderate- or mixed-severity fire regimes are to restore successionally diverse landscapes that are resistant and resilient to current and future stressors. Maintaining native species and characteristic processes requires this successional diversity, but methods to achieve it are poorly explained in the literature. In the Inland...
Wildfire risk in temperate forests has become a nearly intractable problem that can be characterized as a socioecological “pathology”: that is, a set of complex and problematic interactions among social and ecological systems across multiple spatial and temporal scales. Assessments of wildfire risk could benefit from recognizing and accounting for...
Published April 1978. 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 2010 Deepwater Horizon oil release posed the challenges of two types of spill: a familiar spill characterized by buoyant oil, fouling and killing organisms at the sea surface and eventually grounding on and damaging sensitive shoreline habitats, and a novel deepwater spill involving many unknowns. The subsurface retention of...
Coal-fired power plants constitute a significant source of energy production for the United States, and are projected to do so for decades to come. Most of the scrutiny coal-fired power plants receive is in the form of environmental concerns regarding green house gas emissions of carbon dioxide, sulfur dioxide, and...
Internal waves and tides are a dominant source of current variability, and they are intermittent and hard to predict. Internal waves can have significant variability in alongshore structure. However, previous studies on internal waves have focused primarily on their cross-shore structure and propagation. For example, while alongshore-propagating superinertial internal tides...
Background. As part of the nationwide student completion agenda, the Achieving the Dream (ATD) national reform network was established to help community colleges quickly institute sustainable change scaled to impact all students at the institution in a short period of time. Although ATD has been in existence for over a...
A diversity in climate, geologic parent material, and soil
characteristics exist in Jackson, Josephine, Coos, and Douglas
Counties of southwest Oregon. Previous field trials and soil testing
results have revealed uncertainties as to the phosphorus (P) status
of the soils in this area. Twenty-four sites from nine agriculturally
significant soil...
Sterols of the yeast Saccharomyces cerevisiae are found in
membranes with a free C-3,β hydroxyl group or stored in lipid
droplets as esters of long-chain fatty acids. We have examined the
distribution of cholesterol into free sterol and steryl ester pools
of a sterol auxotrophic strain of Saccharomyces cerevisiae. Varying...
Much attention has been given to how to model the price spread since Gardner's important contribution was published in the mid seventies. Most farm-retail price spread studies are applied on agriculture products restricted to domestic trade only. Globalization and weaker trade barriers allow products to reach new markets, and at...
Data is limited evaluating infrequent supplementation of urea or biuret to ruminants consuming low-quality forage (<6% crude protein). Therefore, a series of experiments were designed to compare the effects of daily (D) and alternate day (2D) supplementation of two non-protein nitrogen (NPN) sources (urea or biuret) to ruminants consuming low-quality...
Before 2002, almost all of the approximately 40,000 acres of land in the Wood River Valley, Oregon were used for intensive, flood-irrigated summer cattle grazing, as it had been for over 100 years. Conservation activity in the valley was limited to a couple of wealthy landowners. But a year after...
Multispan skyline logging systems are cable systems designed to yard logs over steep terrain having a constant or convex slope. An intermediate skyline support is used to raise the skyline high enough to achieve ground clearance without overstressing the skyline. Certain improvements in performance can be realized by providing intermediate...
We compare two families of continued fractions algorithms, the symmetrized Rosen algorithm and the Veech algorithm. Each of these algorithms expands real numbers in terms of certain algebraic integers. We give explicit models of the natural extension of the maps associated with these algorithms; prove that these natural extensions are...
We give explicit pseudo-Anosov homeomorphisms with vanishing
Sah–Arnoux–Fathi invariant. Any translation surface whose Veech group
is commensurable to any of a large class of triangle groups is shown to have
an affine pseudo-Anosov homeomorphism of this type. We also apply a reduction
to finite triangle groups and thereby show the...
We give continued fraction algorithms for each conjugacy class of triangle Fuchsian group of signature
(3, n, ∞), with n ≥ 4. In particular, we give an explicit form of the group that is a subgroup of the Hilbert
modular group of its trace field and provide an interval map...
Control abstraction is the process by which programmers define new control constructs by specifying an ordering of statement execution. Using control abstraction, we can create new control constructs for parallel programming, separate the specification of parallelism and synchronization from the rest of the application code, and vary the parallelism exploited...
In order to survive and prosper fishing companies have to balance the need for continuity and change. Investment strategy is a good indicator on the direction companies are headed in terms of capacity, onboard production, and the financial risks they are willing to take. However, the success of an investment...
Previously published physical and biological data document a zonally oriented frontal region within the California Current system separating colder and more eutrophic water north of ≈33°N from warmer; more stratified, and oligotrophic water farther to the south. Satellite images of phytoplankton pigment from the coastal zone color scanner from 1979-1983...
A 5-year time series of coastal zone color scanner imagery (1980-1983, 1986) is used to examine
changes in the large-scale pattern of chlorophyll pigment concentration coincident with the spring
transition in winds and currents along the west coast of North America. The data show strong
interannual variability in the timing...
Bayocean sand spit lies along the northern Oregon coast
approximately 70 miles south of the Columbia River. Work was
begun on the construction of a large recreational resort on the spit
in the early 1900's. At the outset, the resort appeared to have a
promising future. However, a three-year delay...
Revised April 1983. Reprinted January 2000. 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
Good management practices are essential if optimum fertilizer responses are to be realized.
These practices include use of recommended varieties, selection of adapted soils, weed control, disease and insect control, good seed bed preparation, proper seeding methods, and timely harvest.
Because of the influence of soil type, climatic conditions, and...
Good management practices are essential if optimum fertilizer responses are to be realized. These practices include use of recommended varieties, selection of adapted soils, weed control, disease and insect control, good seedbed preparation, proper seeding methods, and timely harvest. Follow recommended soil sampling procedures to estimate fertilizer needs. The Oregon...
This paper presents the initial results from an empirical study of mechanical design engineers. In this study, six engineers were video-taped solving real mechanical design problems. Preliminary analysis of this protocol data has yielded several important findings, including (a) mechanical designers progress from systematic to opportunistic behavior as the design...
Understanding the effects of climate variability on growth dynamics and timing of early life history events in marine fishes can provide insights into survival, recruitment and productivity. We examined interannual variation in indicators of larval growth rates, size at hatch and metamorphosis, and the timing of metamorphosis of northern rock...
This report has three primary objectives; it attempts to examine the relationship of various cultural systems to the marine environment, seeks to create an inventory of uses man has put the marine environment to, and makes an analysis of the attitudes of people towards the marine environment.
A wide variety of organisms show morphologically plastic responses to environmental
stressors but in general these changes are not reversible. Though less common, reversible
morphological structures are shown by a range of species in response to changes in predators,
competitors, or food. Theoretical analysis indicates that reversible plasticity increases fitness...
The effects of precommercial thinning on the understory vegetative cover of 16- to 18-year-old spruce–hemlock (Picea sitchensis (Bong.) Carrière – Tsuga heterophylla (Raf.) Sarg.) stands were studied in seven replicate areas over seven growing seasons postthinning. Vegetative cover was analyzed at the class level, but species-specific effects were examined in...
Growth increment widths from hard structures of marine and freshwater fish and bivalve species are increasingly used to model growth and elucidate relationships with environmental variability. Fully characterizing the intrinsic age-related growth variation among individuals within and between populations, while estimating the extrinsic environmental effects simultaneously, can be challenging. Using...
While much effort has been directed at determining the spatial scales of adaptation in thermal reaction norms for growth, it is widely assumed that these reaction norms have high temporal stability. Water temperatures in the Gulf of Alaska in 2007 were the coldest on record since the mid-1970s and we...
Despite the importance of Pacific cod in Bering Sea fisheries and foodwebs, little is known about the habitat use and the distribution of early life stages. We analysed 6 years of catch data for 0-group Pacific cod in fishery-independent surveys of the Bering Sea shelf. Juvenile cod were most commonly...
Many Gram-negative bacteria use a type III secretion system (T3SS) to establish associations with their hosts. The T3SS is a conduit for direct injection of type-III effector proteins into host cells, where they manipulate the host for the benefit of the infecting bacterium. For plant-associated pathogens, the variations in number...
Monthly composite images from the global coastal zone color scanner
(CZCS) data set are used to provide an initial illustration and comparison of seasonal
and interannual variability of phytoplankton pigment concentration along the western
coasts of South and North America in the Peru Current system (PCS) and California
Current system...
The first three years of SeaWiFS data (1997-2000) provide the most complete quantification to date of chlorophyll seasonal variability along the full latitudinal extent of the four major eastern boundary currents (EBCs). Comparisons to previously published chlorophyll seasonal climatologies deduced from the relatively sparse coverage provided by the Coastal Zone...
Abstract: Relationships between tree traits and tree value for lumber production were investigated. For the purposes of
estimating relative economic weights for use in multitrait selection in coastal Douglas-fir (Pseudotsuga menziesii
(Mirb.) Franco var. menziesii), tree height, diameter at breast height, and branch diameter were measured on 164 trees
(ages...
People interested in economic development in rural communities are often faced with the need to estimate impacts of economic changes or to forecast population, employment, business activity, or public service demands.
An economic "tool" that is often used to assist in this task is the "multiplier." This circular is designed...
A significant step transition between seasonally stratified and destratified hydrographic conditions occurred during an October 2008 cruise to the Florida Panhandle Shelf along a cross-shelf transect that was sampled before and after a cold front passed through the area. Meteorological measurements from nearby ocean and land-based stations characterized the event....
We analyzed the sedimentological characteristics and magnetic properties of cores from the three basins of Clear Lake, California, USA, to assess the depositional response to a series of land use changes that occurred in the watershed over the 20th century. Results indicate that distinct and abrupt shifts in particle size,...
Because invasive annual grasses can strongly influence soil resource availability and disturbance regimes to favor their own
persistence, there is a great need to understand the interrelationships among invasive plant abundance, resource availability, and
desirable species prominence. These interrelationships were studied in two salt desert sites where the local abundance...
Red clover is an important seed and forage crop in western Oregon. Lime, phosphorus, potassium, sulfur, and boron will increase yields under some western Oregon soil conditions. The need for nutrients other than sulfur can be estimated using a soil test. Red clover is best adapted to well-drained soils. Good...
The characterization of temporal and spatial distribution of sunlight is essential for understanding energy transport in natural ecosystems. Fiber-optic distributed temperature sensing (DTS) allows meter resolution measurements of temperature at subminute resolution. The difference in temperature due to absorption and reflection of a pair of helically twisted black and white...
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
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
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
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
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
Satellite-derived pigment concentrations from the west coast time series (WCTS) are averaged into monthly mean fields over the California Current system (CCS) for the period July 1979 to June 1986. Errors caused by the scattering algorithm used in the WCTS are reduced by an empirical correction function, although winter values...
Small-scale turbulence is a random phenomenon, and theoretical relationships about turbulent processes are often only crude approximations. There are relatively few accurate statements that can be made about a turbulent flow without recourse to experimental evidence from flow itself (Tennekes and Lumley, 1972). In the atmosphere, turbulent flows are relatively...
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...
This paper examines albedo perturbation and radiative forcing after a high-severity fire in a
mature forest in the Oregon Cascade Range. Correlations between postfire albedo and seedling, sapling,
and snag (standing dead tree) density were investigated across fire severity classes and seasons for years
4-15 after fire. Albedo perturbation was...
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snag attrition on albedo and radiative forcing
Thomas L. O’Halloran1, Steven A. Acker2, Verena M
This paper examines albedo perturbation and radiative forcing after a high-severity fire in a
mature forest in the Oregon Cascade Range. Correlations between postfire albedo and seedling, sapling,
and snag (standing dead tree) density were investigated across fire severity classes and seasons for years
4-15 after fire. Albedo perturbation was...
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., Acker, S. A., Joerger, V. M., Kertis, J., & Law, B. E. (2014).
Postfire influences of snag attrition on
Growing evidence indicates that disrupting the microbial community that comprises the intestinal tract, known as the gut microbiome, can contribute to the development or severity of disease. As a result, it is important to discern the agents responsible for microbiome disruption. While animals are frequently exposed to a diverse array...
Growing evidence indicates that disrupting the microbial community that comprises the intestinal tract, known as the gut microbiome, can contribute to the development or severity of disease. As a result, it is important to discern the agents responsible for microbiome disruption. While animals are frequently exposed to a diverse array...
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Restructuring of the Microbiome in Adult
Zebrafish
Christopher A. Gaulke1, Carrie L. Barton2,3, Sarah
Self-assembly of recombinant proteins within the biosilica of living diatoms represents a means to construct functional materials in a reproducible and scalable manner that will enable applications that harness the inherent specificities of proteins to sense and respond to environmental cues. Here we describe the use of a silaffin-derived lysine-rich...
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Xiong,† Nicole R. Ford,‡ Karen A. Hecht,‡ Guritno Roesijadi,‡, § and
Thomas C. Squier
Self-assembly of recombinant proteins within the biosilica of living diatoms represents a means to construct functional materials in a reproducible and scalable manner that will enable applications that harness the inherent specificities of proteins to sense and respond to environmental cues. Here we describe the use of a silaffin-derived lysine-rich...
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Engineered Diatom
Biosilica Matrices
Yijia Xiong,† Nicole R. Ford,‡ Karen A. Hecht,‡ Guritno Roesijadi
Self-assembly of recombinant proteins within the biosilica of living diatoms represents a means to construct functional materials in a reproducible and scalable manner that will enable applications that harness the inherent specificities of proteins to sense and respond to environmental cues. Here we describe the use of a silaffin-derived lysine-rich...