bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors that Influence Administrative Appeals of Proposed USDA Forest Service Fuels Reduction Actions
Authors: Laband David N. , González-Cabán Armando , Hussain Anwar 
Published: April 2024

Abstract
Using the database developed by the General Accounting Office on proposed fuels reduction actions on federal lands in 2001 and 2002, we conduct probit regression analysis to identify factors that significantly affect the likelihood of administrative appeal. The likelihood of appeal of a proposed fuels reduction action is significantly increased by (1) the size of area affected, (2) the number of proposed activities at the site, (3) when one of the stated purposes is commodity production (timber and sawlogs), (4) when one of the stated purposes is reduction of project-generated fuels, (5) implementation involves prescribed burning or mechanical thinning, and (6) the presence of at least one species of mammal at risk of extinction in the immediate vicinity of the site. Conversely, the likelihood of appeal is significantly reduced if (7) implementation is handled by Forest Service personnel or using a service contract, and (8) the proposed action is located in a Wildland–Urban Interface area. However, we also observe persistent regional effects, with fuels reduction proposals in Region 1 (3, 6, 8) characterized by a significantly higher (lower) likelihood of appeal than proposals in the other regions.
Landscape-Level Impact of Beech Bark Disease in Relation to Slope and Aspect in New York State
Authors: Munck I.A. , Manion P.D. 
Published: April 2024

Abstract
During the past 40 years, the beech bark disease complex has destabilized the beech component of New York State forests, but a selected portion of the American beech (Fagus grandifolia) population has attained a sustainable forest structure. The influence of slope and aspect in relation to beech bark disease on the sustainability of American beech populations was evaluated. There were differences in the proportion of American beech trees with signs of Neonectria spp. and beech scale (Cryptococcus fagisuga) on eastern and western aspects on slopes ≥16%. American beech populations on northern, northeastern, eastern, southeastern, and southern aspects on slopes ≥16% (23–29% of the sample) displayed diameter distributions that would sustain the current forest structure. In all other sites, observed percentage mortality in the large-diameter classes was higher than predicted, suggesting a future shift in forest structure toward lower densities of large trees in these sites.
Research and Development Operations and Foreign Expansion of Multinational Companies: Evidence from Forest Industry Microdata
Authors: Laaksonen-Craig Susanna , Uusivuori Jussi 
Published: April 2024

Abstract
This article examines the impacts of research and development on the mode of multinational expansion (exports versus foreign sales) by forest products companies, and the effects of firms' international strategy on the level of research and development investments. A theoretical model of imperfect competition between international companies is derived and company-level data representing Finnish forest industries are used. The results indicate that the firms' own research and development investments helped, at least during the 1980s, their foreign expansion by favoring the firms' exports rather than foreign sales. External research and development investments by other companies were substitutes for a firm's own investment on research and development in the 1980s, but this effect seems to have disappeared toward the 1990s. There have not appeared to be any significant spillover effects from the research and development activities across the firms.
Innovativeness in the North American Softwood Sawmilling Industry
Authors: Crespell Pablo , Knowles Christopher , Hansen Eric 
Published: April 2024

Abstract
The North American forest products industry has traditionally maintained a production orientation and a commodity mentality toward operations, with much of the industry following a low-cost strategy and concentrating on wood fiber recovery. The propensity to innovate (innovativeness) is important for maintaining firm competitiveness. To assess industry practices with respect to innovativeness, United States and Canadian softwood sawmills were surveyed. Respondents rated themselves more innovative with respect to manufacturing processes as compared to product and business systems innovations. Innovativeness and market orientation were found to be positively correlated. High- and medium-innovative mills were consistently different (e.g., more market-oriented, more structured new product development processes) from low-innovative mills.
Bootstrap Simulation and Response Surface Optimization of Management Regimes for Douglas-Fir/Western Hemlock Stands
Authors: Liang Jingjing , Buongiorno Joseph , Monserud Robert A. 
Published: April 2024

Abstract
A method was proposed to simulate forest stand growth, timber prices, and interest rates by distribution-free bootstrapping, and then optimize management controls for economic and ecological objectives by response surface analysis. The method was applied to Douglas-fir/western hemlock stands to predict the effects on economic and ecological objectives of management alternatives defined by the cutting cycle, C, the residual stand basal area, B, the diameter of the largest tree, D, and the ratio, q, of the number of trees in adjacent diameter classes. The effects were described with response surfaces, which were used to determine the best combinations of B, q, and C for each management criterion. Adjusting B, q, and C could control for 97 to 99% of the variability in the expected value of species diversity, size diversity, percentage of peeler logs, and basal area, and for 80 to 90% of the variability in land expectation value and annual production. Economic and ecologic criteria were generally most sensitive to the q ratio, the residual basal area, and the cutting cycle. Annual production was negatively correlated with tree size diversity and wood quality. There was no apparent conflict between stand diversity and wood quality.
Forest Volume and Biomass Estimation Using Small-Footprint Lidar-Distributional Parameters on a Per-Segment Basis
Authors: Aardt Jan A.N. van , Wynne Randolph H. , Oderwald Richard G. 
Published: April 2024

Abstract
This study assessed a lidar-based, object-oriented (segmentation) approach to forest volume and aboveground biomass modeling. The study area in the Piedmont physiographic region of Virginia is composed of temperate coniferous, deciduous, and mixed stands. Segmentation objects, hierarchical in terms of area and ranging from 0.035 to 5.632 ha/object, were created using a lidar-derived canopy height model. Horizontal point (basal area) samples were used to calculate volume and aboveground biomass. Per-object lidar point (per return height and intensity) distributional parameters were extracted from small-footprint lidar. Adjusted R 2 and Mallow's Cp metrics were used to select models for the range of segmentation results. Selected variables included intensity-based and structurally related first through fifth return height parameters. Object-based modeling (adjusted R 2 = 0.58–0.79; various object sizes) resulted in distinct improvements over stand-based attempts (adjusted R 2 = 0.40–0.73; majority adjusted R 2 &lt; 0.50). Adjusted R 2 and RMSE values for deciduous volume (0.59; 51.15 m3/ha) and biomass (0.58; 37.41 Mg/ha) were better than those found for another, plot-based study in the study area. Coniferous R 2 values for volume (0.66) and biomass (0.59) were lower than previous studies, which was attributed to variability within the relatively narrow volume range (6.94–50.93 m3/ha).
A Generalized Approach for Modeling and Localizing Stem Profile Curves
Authors: Trincado Guillermo , Burkhart Harold E. 
Published: April 2024

Abstract
The Max and Burkhart segmented taper equation was fitted using nonlinear mixed-effects modeling techniques to account for within- and between-individual variation in loblolly pine (Pinus taeda L.) stem profiles. Within- and between-tree residual variances and spatial autocorrelation between residuals were incorporated in the model with an error variance function and a continuous autocorrelation structure, respectively. However, most of the residual autocorrelation was accounted for by including random effects. Upper stem diameter measurements were used to estimate random effects parameters using an approximate Bayesian estimator, which localized stem profile curves for individual trees. The procedure was tested with an independent data set. Measures of precision and bias showed that upper stem diameter measurements and subsequent estimates of random effects improved the predictive capability of the taper equation mainly in the lower portion of the bole. The method can localize stem curves for trees growing under different site and management conditions. It also represents a general framework that can be applied to other taper equation forms, increasing their flexibility and efficiency in prediction for local conditions.
Carbon and Nitrogen Cycling in Southwestern Ponderosa Pine Forests
Authors: Hart Stephen C. , Selmants Paul C. , Boyle Sarah I. , Overby Steven T. 
Published: April 2024

Abstract
Ponderosa pine forests of the southwestern United States were historically characterized by relatively open, parklike stands with a bunchgrass-dominated understory. This forest structure was maintained by frequent, low-intensity surface fires. Heavy livestock grazing, fire suppression, and favorable weather conditions following Euro-American settlement in the late 19th century resulted in a dramatic increase in pine regeneration. Today, many of these forest stands have high stand densities with low understory production, and are susceptible to infrequent, stand-replacing fires. The primary objective of our study was to better characterize the contemporary carbon (C) and nitrogen (N) cycling processes in relatively unmanaged southwestern ponderosa pine stands. We then compared these ecosystem conditions with those of an adjacent stand that had received an ecological restoration treatment that included thinning and prescribed burning. Our results suggest that N availability and aboveground net primary productivity (ANPP) of trees in these forests are low compared to other forests. Restoration treatments decreased ANPP but increased the proportion of ANPP in woody tissues. These treatments also increased soil respiration, water availability, temperature, and net nitrification, but had no effect on net N mineralization and microbial N. We speculate that the understory response to restoration treatments is a key factor affecting the overall ecosystem response in these forests.
Spatial Patterns of Modern Period Human-Caused Fire Occurrence in the Missouri Ozark Highlands
Authors: Yang Jian , He Hong S. , Shifley Stephen R. , Gustafson Eric J. 
Published: April 2024

Abstract
The spatial pattern of forest fire locations is important in the study of the dynamics of fire disturbance. In this article we used a spatial point process modeling approach to quantitatively study the effects of land cover, topography, roads, municipalities, ownership, and population density on fire occurrence reported between 1970 and 2002 in the Missouri Ozark Highland forests, where more than 90% of fires are human-caused. We used the AIC (Akaike information criterion) method to select an appropriate inhomogeneous Poisson process model to best fit to the data. The fitted model was diagnosed using residual analysis as well. Our results showed that fire locations were spatially clustered, and high fire occurrence probability was found in areas that (1) were public land, (2) within 6 km to 17 km of municipalities, and (3) &lt;500 m from roads where forests are accessible to humans. In addition, fire occurrence probability was higher in pine-oak forests on moderate (&lt;25 degree) slopes and xeric aspects and at higher (&gt;270 m) elevations, reflecting the effects of natural factors on fire occurrence. The results serve as a provisional hypothesis for expanding fire risk estimation to surrounding areas. The spatial scale of analysis (approximately 1 ha) provides new information to guide planning and risk reduction efforts.
Sediment and Wood Routing in Steep Headwater Streams: An Overview of Geomorphic Processes and their Topographic Signatures
Authors: May Christine 
Published: April 2024

Abstract
Headwater streams in steep terrain pose a significant challenge for the development of best management practices (BMP) in forested watersheds. There is an incomplete understanding of the processes that govern the input, storage, and transport of sediment and wood, and these processes differ geographically. At the upstream extent of the channel network, headwater streams represent a transition from hillslope to channel processes. At the downstream extent, many of these channels transition from mass wasting to fluvial process dominance. Large-scale sediment routing processes typically consist of debris flows, earth flows, and/or gully erosion. In the interval between episodic transport events, headwater streams can interrupt the delivery of sediment from hillslopes to larger river systems by storing large volumes of sediment and wood. Forest management guidelines typically identify headwater streams as occurring upstream of the distribution of fish; however, a topographically based designation of headwater streams could prove useful for identifying which erosional processes are dominant in a particular area. Broad-scale terrain analysis based on unique topographic signatures can be used to identify the spatial domain of different geomorphic landforms that govern headwater stream processes, how they may be affected by forest management, and to infer the type and severity of downstream disturbance.
Influence of Headwater Streams on Downstream Reaches in Forested Areas
Authors: MacDonald Lee H. , Coe Drew 
Published: April 2024

Abstract
The source areas of headwater streams typically compose 60% to 80% of a catchment. This, plus the typical increase in precipitation with elevation, means that headwater streams generate most of the streamflow in downstream areas. Headwater streams also provide other important constituents to downstream reaches, including coarse and fine sediment, large woody debris, coarse and fine organic matter, and nutrients. The relative importance of headwater streams as a source of these other constituents is highly variable because the amount and quality of each constituent can be modified by in-channel storage, dilution, biological uptake, diminution, and chemical transformations. Headwater sources of water, fine sediment, and fine particulate organic matter are more likely to be delivered to downstream reaches than coarse sediment, woody debris, nutrients, or an increase in water temperatures. The complexity and temporal variability of channel-hillslope interactions, in-channel processes, and downstream conditions makes it difficult to rigorously link upstream inputs and anthropogenic activities to the condition of downstream resources. These issues may preclude the use of adaptive management, particularly in larger basins, as adaptive management implicitly assumes that (1) downstream changes can rapidly be detected, (2) management will change rapidly in response to any adverse change, and (3) a management change will rapidly improve the affected resource. Since these assumptions may be difficult to satisfy—particularly in larger basins—the use of adaptive management must be carefully examined before it can be applied at the watershed scale.
Riparian Buffer and Density Management Influences on Microclimate of Young Headwater Forests of Western Oregon
Authors: Anderson Paul D. , Larson David J. , Chan Samuel S. 
Published: April 2024

Abstract
Thinning of 30- to 70-year-old Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) stands is a common silvicultural activity on federal forest lands of the Pacific Northwest, United States. Empirical relationships among riparian functions, silvicultural treatments, and different riparian buffer widths are not well documented for small headwater streams. We investigated buffer width and density management effects on riparian microclimates of headwater streams in western Oregon. Spatial variations in stand density, canopy cover, and microclimate were measured along transects extending from stream center upslope into thinned stands, patch openings, or unthinned stands, with riparian buffers ranging from &lt;5 m up to 150 m width. For treated stands, summer mean daily air and soil temperature maxima increased, and mean daily humidity minima decreased with distance from stream. Microclimate gradients were strongest within 10 m of stream center, a distinct area of stream influence within broader riparian areas. Thinning resulted in subtle changes in microclimate as mean air temperature maxima were 1 to 4°C higher than in unthinned stands. With buffers 15 m or greater width, daily maximum air temperature above stream center was less than 1°C greater, and daily minimum relative humidity was less than 5% lower than for unthinned stands. In contrast, air temperatures were significantly warmer within patch openings (+6 to +9°C), and within buffers adjacent to patch openings (+3°C) than within unthinned stands. Buffers of widths defined by the transition from riparian to upland vegetation or topographic slope breaks appear sufficient to mitigate the impacts of upslope thinning on the microclimate above headwater streams.
Vertebrate Assemblages Associated with Headwater Hydrology in Western Oregon Managed Forests
Authors: Olson Deanna H. , Weaver George 
Published: April 2024

Abstract
We characterized headwater stream habitats, fish and amphibian fauna, in and along 106 headwater stream reaches at 12 study sites within managed forest stands 40 to 70 years old in western Oregon. Headwater stream types in our sample included perennial, spatially intermittent, and dry reaches. We captured 454 fish of three species groups and 1,796 amphibians of 12 species. Using canonical correlation, nonmetric multidimensional scaling ordination, and generalized linear models, we identified species and assemblages associated with reach hydrologic type (e.g., perennial, intermittent, dry), stream size, gradient, and substrate composition. Our findings of torrent salamander (Rhyacotriton species) occurrences in spatially intermittent streams, and patchy and infrequent occurrences of Cottus fish (sculpins) and coastal tailed frogs (Ascaphus truei Stejneger) suggests these taxa warrant consideration during headwater management for retention of locally distinct biotic resources.
Structures Linking Physical and Biological Processes in Headwater Streams of the Maybeso Watershed, Southeast Alaska
Authors: Bryant Mason D. , Gomi Takashi , Piccolo Jack J. 
Published: April 2024

Abstract
We focus on headwater streams originating in the mountainous terrain of northern temperate rain forests. These streams rapidly descend from gradients greater than 20% to less than 5% in U-shaped glacial valleys. We use a set of studies on headwater streams in southeast Alaska to define headwater stream catchments, link physical and biological processes, and describe their significance within watersheds. We separate headwater stream systems into four units that have distinct hydrologic and geomorphic processes that link terrestrial processes to aquatic systems. Headwater streams collect, process, and transport material downstream. Physical and biological processes in headwater streams are complex and closely tied to terrestrial processes. Steps and step pools formed by large wood are keystone structures that link physical processes to biological processes and increase channel complexity. Large and coarse wood debris dams form in-channel step structures and act as valves that regulate the downstream flow of material. A large amount of inorganic and organic sediment is stored in step structures, which may be biological hotspots in headwater streams. Step pools formed by large woody debris are critical habitat for Dolly Varden (Salvelinus malma), juvenile coho salmon (Oncorhynchus kisutch), steelhead (O. mykiss), and cutthroat trout (O. clarkii) in reaches with gradients from less than 4% to those greater than 10%. Landslides and debris flows are the dominant channel-altering processes in headwater streams and remove the step profile. Management activities that increase the number and frequency of channel disturbance events in headwater streams can have important and long-term consequences throughout a watershed.
Modeling Pulpwood Trade within the United States South
Authors: Polyakov Maksym , Teeter Lawrence 
Published: April 2024

Abstract
Interregional trade of roundwood products is an important factor of regional roundwood markets. Until now, regional and subregional forest sector models did not account for the spatial aspects of roundwood markets. This article explores ways to model interregional trade of roundwood products. It compares the performance of different specifications of a gravity model (the model widely used in the analysis of international trade) and a fixed gravity coefficient model (common in regional input-output analysis) to forecast pulpwood trade between the states of the United States South. The gravity model estimated using nonlinear least-squares with fixed effects (NLS FEM) and the fixed gravity coefficient model (FGCM) showed the best results. Another important result of this study is the finding that the fixed gravity coefficients for pulpwood trade in the United States South are temporally stable. This suggests the possibility of using the FGCM for modeling roundwood trade in the absence of time series data.
Comparison of Methods to Estimate Reineke's Maximum Size-Density Relationship Species Boundary Line Slope
Authors: VanderSchaaf Curtis L. , Burkhart Harold E. 
Published: April 2024

Abstract
Maximum size-density relationships (MSDR) provide natural resource managers useful information about the relationship between tree density and average tree size. Obtaining a valid estimate of how maximum tree density changes with changes in average tree size is necessary to describe these biological relationships accurately. This article examines three methods to estimate the slope (b) of the MSDR species boundary line across a range of planting densities: ordinary least-squares (OLS), first-difference model, and the linear mixed-effects model. For this article, stability refers to the extent to which parameter estimates do not change when the range of planting densities in the fitting data set changes. When using data from a planting density trial consisting of planting densities ranging from 6,727 to 747 seedlings per hectare, mixed-effect models produced the most stable estimates of b while OLS resulted in the least stable estimates. MSDR boundaries have been defined as either (1) those that describe the boundaries of individual stands (MSDR dynamic thinning line) or (2) those that describe MSDRs common across all sites for a particular species in a certain geographical region (MSDR species boundary line). A further refinement of the MSDR species boundary line is proposed by defining two MSDR species boundary lines, labeled here as I and II. Although both MSDR species boundary lines are positioned above all observations, one MSDR species boundary line, II, has a slope that can be considered the population average of all MSDR dynamic thinning lines; the other species boundary line (I) has a slope that results from positioning the boundary above all observations without accounting for self-thinning patterns of individual stands. A mixed-effects analysis was used to estimate the slope of MSDR species boundary line II.