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...