bluuebunny/crossref_metadata_2025_split huggingface dataset:
Derivation, Fitting, and Implication of a Compatible Stem Taper-Volume-Weight System for Intensively Managed, Fast Growing Loblolly Pine
Authors: Zhang Yujia , Borders Bruce E. , Bailey Robert L. 
Published: April 2024

Abstract
Geometry-oriented methodology yielded a compatible taper-volume-weight system of models whose parameters were estimated using data from intensively managed loblolly pine (Pinus taeda L.) plantations in the lower coastal plain of Georgia. Two segments (separated at a stem ratio of 0.60 of total height) depicted taper, volume, and weight variations of the stems as well. The taper function defines stem taper as a proportion of the diameter at breast height. The segmented volume equation was derived from integration of the taper function along the stem, and it can be readily transformed into a ratio volume equation. Likewise, the segmented weight equation was obtained from integration of the volume function and a wood density function. Data analysis showed that fertilization has significantly reduced taper (inside and outside bark) on the upper segment and augmented stem merchantable volume in this segment. However, unit-weight (green wood and bark, green wood only, and dry wood only) was not significantly different between fertilized and unfertilized trees, implying that annual fertilization did not reduce the specific gravity very much. Finally, our analysis showed no significant impacts of complete vegetation control on taper, volume or weight characteristics. FOR. SCI. 48(3):595–607.
Harvest Scheduling with Area-Based Adjacency Constraints
Authors: McDill Marc E. , Rebain Stephanie A. , Braze Janis 
Published: April 2024

Abstract
Adjacency constraints in harvest scheduling models prevent the harvest of adjacent management units within a given time period. Two mixed integer linear programming (MILP) harvest scheduling formulations are presented that include adjacency constraints, yet allow the simultaneous harvest of groups of contiguous management units whose combined areas are less than some predefined limit. These models are termed Area Restriction Models, or ARMs, following Murray (1999). The first approach, the Path Algorithm, generates a set of constraints that prevent concurrent harvesting of groups of contiguous stands only when the combined area of a group exceeds the harvest area restriction. The second approach defines the set of Generalized Management Units (GMUs) that consist of groups of contiguous management units whose combined areas do not exceed the maximum harvest area limit. This formulation of the model can recognize direct cost savings—such as sale administration costs or harvest costs—or higher stumpage prices that may be realized by jointly managing stands. Example problems are formulated and solved using both ARM approaches and compared with models that restrict concurrent harvests on all adjacent units, regardless of area [termed Unit Restriction Models, or URMs, again following Murray (1999)]. The ARM formulations usually result in larger models and take longer to solve, but allow for higher objective function values than otherwise similar URM formulations. While the proposed ARM approaches should be applicable to more general problems, the examples are constructed so that the largest number of contiguous stands that can be harvested jointly is three. Strategies for reducing the size of the ARM formulations are discussed and tested. FOR. SCI. 48(4):631–642.
Bayesian Melding of a Forest Ecosystem Model with Correlated Inputs
Authors: Radtke Philip J. , Burk Thomas E. , Bolstad Paul V. 
Published: April 2024

Abstract
Bayesian melding, a method for assessing uncertainties in deterministic simulation models, was augmented to make use of prior knowledge about correlations between model inputs. The augmentation involved the use of a nonparametric correlation induction algorithm. The modified Bayesian melding technique was applied to the process-based forest ecosystem computer model PnET-II. The Bayesian posterior distribution for this analysis did not reflect prior knowledge of input correlations for five input pairs tested unless the correlations were explicitly accounted for in the Bayesian prior distribution. For other input pairs not known to be correlated prior to the analysis, numerous significant posterior correlations were identified. For one such pair of model inputs, a moderate posterior correlation was substantiated by empirical evidence that had not previously been taken into consideration. We conclude that, when possible, efforts should be made to account for prior knowledge of correlated inputs; however, Bayesian melding may elucidate input correlations in its posterior sample, even when no prior knowledge of such correlations exists. FOR. SCI. 48(4):701–711.
An Indirect Search Algorithm for Harvest-Scheduling Under Adjacency Constraints
Authors: Crowe Kevin , Nelson John 
Published: April 2024

Abstract
An indirect search heuristic is described for solving harvest-scheduling problems under adjacency constraints. This method works in combination with a greedy algorithm by diversifying the search through random changes in prioritized harvest queues. The indirect search is tested on a series of tactical problems and compared with published results for tabu search, simulated annealing, integer programming and linear programming. Results for large strategic problems are compared to a simulated annealing search algorithm. Objective function values are comparable to tabu search and simulated annealing, and solution times range from 38 seconds to 40 minutes, depending on the problem size and the number of iterations. Benefits of the indirect search method are: (1) objective function values can be higher than those computed through other heuristic algorithms, and (2) the algorithm produces good results without time-consuming experimentation with parameters of the search algorithm. The method also has potential for solving more complicated, multiple objective problems. FOR. SCI. 49(1):1–11.
Landscape Ecosystems of Northern Lower Michigan and the Occurrence and Management of the Kirtland's Warbler
Authors: Kashian Daniel M. , Barnes Burton V. , Walker Wayne S. 
Published: April 2024

Abstract
The Kirtland's warbler (Dendroica kirtlandii Baird) is an endangered songbird that nests in northern Lower Michigan in ecosystems dominated by young jack pine (Pinus banksiana Lamb.). An ecological, multifactor approach was used to determine the range and characteristics of landform-level ecosystems supporting the warbler and to compare the spatial and temporal patterns of warbler occupation among these ecosystems. Using an ecosystem rather than a strictly biological approach, the landforms occupied by the warbler are very diverse. Twelve landforms were identified based on 61 sites currently or formerly occupied by the warbler. Average annual jack pine height growth, an indicator of stand structural features that influences initial warbler colonization and duration of occupancy, differed significantly among landforms, resulting in marked differences in warbler occurrence in time and space across the breeding range. Landforms with favorable growing conditions for jack pine were colonized earliest and were occupied for the shortest duration, whereas landforms with unfavorable growing conditions were colonized relatively late but were occupied longest. Different ecological factors, such as the spatial position of landforms, microclimate, soil texture, or a combination of these factors, may account for favorable or unfavorable growing conditions for jack pine, which in turn affects the timing and duration of warbler occupancy. The classification and description of ecosystems occupied by the warbler provides an ecological framework for warbler management, especially when plantations rather than wildfire are the primary source of warbler habitat. FOR. SCI. 49(1):140–159.
Book Reviews: Burning Questions: A Social Science Research Plan for Federal Wildland Fire Management
Authors: Hesseln Hayley 
Published: April 2024

Abstract
Social science will play an important role in addressing wildfire issues in the 21st century as fire risk continues to escalate and society moves farther into forests and wildlands at the periphery of urbanization. A better understanding of the social relationships encompassing fire management will be useful for policymakers, fire personnel, and the public. Furthermore, the use of social science will be beneficial in elucidating the complex relationships among these groups.
Guided Transect Sampling with a New Strategy for Second-Stage Guidance
Authors: Ringvall Anna 
Published: April 2024

Abstract
Guided transect sampling (GTS) was recently proposed as a method for surveying sparse and geographically scattered populations if prior information with high spatial resolution is available. With this method, wide survey strips are, during a first stage, randomly selected in the area to be surveyed. In the second stage, the selected first-stage strips are subsampled with a survey line or survey strip based on the prior information. In this article, a new strategy for second-stage guidance is developed and evaluated in a simulation study. The suggested strategy uses an assumed model for the relationship between the prior information and the variable of interest to find an efficient design for selecting the second-stage transects. The performance of the suggested strategy is evaluated in terms of the variance obtained in different realizations of the assumed model. Results from the simulation study indicate that the suggested strategy is an efficient alternative to previously suggested strategies, if the correspondence between the model population and the real population is good. On the other hand, if the difference between the two populations is large, large variances were sometimes obtained. FOR. SCI. 49(2):169–175.
Photosynthesis and Growth in Seedlings of Five Forest Tree Species with Contrasting Leaf Anatomy Subjected to Supplemental UV-B Radiation
Authors: Bassman John H. , Edwards Gerald E. , Robberecht Ronald 
Published: April 2024

Abstract
Seeds or cuttings of five forest tree species with contrasting leaf anatomies and shoot growth characteristics were cultivated under three different UV-B radiation regimes: ambient (7.5 kJ m-2 d-1 = 1×), two times ambient (2×), or three times ambient (3×) biologically effective UV-B radiation (UV-BBE) USA at the summer solstice, as calculated for Pullman, Washington. Experiments were conducted in glasshouses using a nonmodulated UV-B lamp system. Gas exchange was measured in recently mature leaves after six months of exposure. Photosynthetic rates were reduced by 2× and 3× treatments in Populus trichocarpa, and by the 3× regime for Pseudotsuga menziesii. Photosynthetic rates increased under the 2× treatment for Pseudotsuga menziesii and under the 3× treatment for Picea engelmannii. For Pinus ponderosa and Quercus rubra, photosynthetic rates were unchanged. Dark respiration increased under both 2× and 3× treatments for Picea engelmannii and by the 3× level in Quercus rubra, but was unaffected in the other species. Transpiration and stomatal conductance generally mirrored changes in photosynthesis. Water use efficiency increased for Pinus ponderosa (2× treatment) and Quercus rubra (2× and 3×), was reduced for Populus trichocarpa (2× & 3×), and remained unchanged in the other species. Enhanced UV-B radiation changed the shape of light response curves for all species. Quantum yields were unchanged for Pinus ponderosa, increased for Pseudotsuga menziesii (2×) and Picea engelmannii (2× and 3×) and were reduced in Populus trichocarpa (2×) and Quercus rubra (3×). Light compensation points were higher in the conifers (3×) and reduced in the angiosperms (2×). Chlorophylls were generally reduced by higher UV-B radiation in the conifers and for Populus trichocarpa (3×), but increased for Quercus rubra. Ultraviolet-absorbing compounds increased in the conifers and were unchanged in the angiosperms by enhanced UV-B radiation. Height growth increased (Pinus ponderosa, 3×; Quercus rubra, 2×), decreased (Picea engelmannii, 3×) or was unchanged (Pseudotsuga menziesii, Populus trichocarpa) by higher levels of UV-B radiation. Stem diameter and plant biomass were generally reduced, and shoot: root ratios increased for all species except Populus trichocarpa. Our results do not appear to support the hypothesis that inherent leaf anatomy or shoot growth pattern in these species directly determine the response of photosynthesis and growth to enhanced UV-B radiation. FOR SCI. 49(2):176–187.
Biomass Partitioning and Growth Efficiency of Intensively Managed Pinus taeda and Pinus elliottii Stands of Different Planting Densities
Authors: Colter Burkes E. , Will Rodney E. , Barron-Gafford Greg A. , Teskey Robert O. , Shiver Barry 
Published: April 2024

Abstract
The effect of planting density (740, 2,220, 3,700, and 4,440 trees/ha-1) on growth efficiency and biomass partitioning was examined in intensively managed stands of 4-yr-old loblolly (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) stands on the Coastal Plain of southern Georgia. The primary objective of this study was to determine whether decreased partitioning of biomass to stem relative to other tree components limits stem biomass growth on a per hectare basis as stand density increases. Fourth growing season stem biomass production did not increase proportionally with planting density, indicating that stem biomass growth was limited at the higher stand densities. For both species, growth efficiency (stem biomass growth produced during the fourth growing season per unit of leaf biomass) was significantly lower for stands planted at 740 trees/ha-1 compared to the other stand densities. Similarly, the ratio of stem biomass growth: fine root biomass was significantly lower for the 740 trees/ha-1 stand. Within sites, planting density had no effect on the ratio of fine root biomass: leaf biomass for either species. Overall, these results indicate that partitioning to stem growth increased relative to foliage or fine roots as stand density increased. Therefore, the limitation in stem biomass growth on a per hectare basis that occurred as stand density increased was not due to changes in partitioning, but probably due to a limitation in net primary production. FOR. SCI. 47(2):224–234.
Valuing Biodiversity, Aesthetics, and Job Losses Associated with Ecosystem Management Using Stated Preferences
Authors: Xu Weihuan , Lippke Bruce R. , Perez-Garcia John 
Published: April 2024

Abstract
The study performs a joint estimation of the values for three important attributes of forest ecosystem management—biodiversity, aesthetics, and rural employment impacts using a choice-based, stated preference approach. It develops the marginal willingness-to-pay schedule for the three attributes for timber rural, other rural, and urban communities in Washington State. In contrast to the conventional wisdom in neoclassical economics, the public perceives job losses as losses of social welfare in this study. There are differences as well as similarities among the preferences of the three communities for the attributes of ecosystem management. The results show that the overall preferences of the timber rural and urban communities towards ecosystem management are substantially different, while the preferences of other rural community are not statistically significantly different from the other two communities. The estimated environmental and social values make it possible for policy makers and resource managers to compare and assess the trade-offs of different management plans. For example, with the biodiversity index level at 60, where an index of 50 relates current conditions, and rural forest-related job losses at 5,000, each household in urban communities in Washington State is willing to pay $31.44 annually for an additional unit of improvement of biodiversity, and $45.97 annually for avoiding an additional 1,000 rural job losses. The trade-off relationship for the given biodiversity and job loss levels suggests each household in urban communities each year is willing to trade 684 additional rural forest-related job losses with one unit of biodiversity improvement, ceteris paribus. Similar trade-off relationships for households in timber and other rural communities suggest each is willing to trade 598 and 388 additional rural forest-related job losses, respectively, with one unit of biodiversity improvement, ceteris paribus. The trade-off between aesthetics and job losses are 1,229, 452, and 686 additional jobs with one unit of aesthetics improvement for urban, timber, and other rural households, respectively. The trade-off relationships provide important information for improving the efficiency and equity of forest ecosystem management. FOR. SCI. 49(2):247–257.
A Comparison of Compatible and Annual Growth Models
Authors: Ochi Norihisa , Cao Quang V. 
Published: April 2024

Abstract
Compatible growth and yield models are desirable because they provide the same growth estimates regardless of length of growth periods. However, the compatibility constraints restrict the number of possible models. This restriction might be overcome by using models that predict annual stand growth based on periodic measurements. The advantages of this approach are (1) the flexibility allowed in building annual growth models without constraints, and (2) the step-invariance property maintained by these models. An annual growth model was developed in this study that predicts yield based on information from the previous year. For 162 plots from the Southwide Seed Source Study of loblolly pine (Pinus taeda L.), the annual growth model provided better predictions of stand survival, basal area, and volume than two compatible growth models. FOR. SCI. 49(2):285–290.
Clustering Versus Regression Trees for Determining Ecological Land Units in the Southern California Mountains and Foothills
Authors: Franklin Janet 
Published: April 2024

Abstract
A landscape stratification was required for simulation modeling of fire disturbance and succession in the mountains and foothills region of the Peninsular Ranges within San Diego County, California. Two quantitative approaches to mapping ecological land units (ELUs) were compared for a 3,878 km2 study area. These were: (a) clustering of climate overlain with key terrain variables; and (b) regression tree modeling of climate, geology, and terrain variables using a normalized difference vegetation index (NDVI), derived from a Landsat Thematic Mapper image, as the dependent variable. Terrain variables derived from a digital elevation model included slope gradient, cosine transformed slope aspect, potential solar insolation, and a topographic moisture index. For the simulation model ELUs were required that would stratify the landscape according to biomass (fuel) accumulation dynamics, related to site productivity, and probabilities of plant species establishment. Therefore, ELUs were defined using abiotic variables, and the resulting stratifications were evaluated by their ability to reduce within-class variance in the NDVI (as an index of biological productivity), and by comparing them to a map of existing vegetation. While the regression tree method resulted in classes that explained more variance in NDVI than classes resulting from unsupervised clustering, the difference was not large. In contrast, the unsupervised approach resulted in ecological land classes that were more strongly related to existing vegetation patterns. FOR. SCI. 49 (3):354–368.
Classification Accuracy for Stratification with Remotely Sensed Data
Authors: Czaplewski Raymond L. , Patterson Paul L. 
Published: April 2024

Abstract
Tools are developed that help specify the classification accuracy required from remotely sensed data. These tools are applied during the planning stage of a sample survey that will use poststratification, prestratification with proportional allocation, or double sampling for stratification. Accuracy standards are developed in terms of an “error matrix,” which is familiar to remote sensing specialists. In addition, guidance is provided to determine when new remotely sensed classifications are needed to maintain acceptable levels of statistical precision with stratification. FOR. SCI. 49(3):402–408.
Combining Remotely Sensed Optical and Radar Data in kNN-Estimation of Forest Variables
Authors: Holmström H. , Fransson J.E.S. 
Published: April 2024

Abstract
The use of optical and radar data for estimation of forest variables has been investigated and evaluated by employing the k nearest neighbor (kNN) method. The investigation was performed at a test site located in the south of Sweden consisting mainly of Norway spruce and Scots pine forests with standwise stem volume in the range of 0–430 m3 ha-1. The kNN method imputes weighted reference plot variables to areas to be estimated (target areas), facilitating further use of data in forestry planning models. Remotely sensed multispectral optical data from the SPOT-4 XS satellite and radar data from the airborne CARABAS-II VHF SAR sensor were used, separately and combined, to define weights in the kNN algorithm. The weights were inversely proportional to the image feature distance between the reference plot and the target area. The distance metric was defined using regression models based on the image data sources. Positive impact on the accuracies of stem volume and age estimates was found by combining the two image data sources. Stem volume, at stand level, was estimated with a RMSE of 37 m3 ha-1 (22% of the true mean value) using the combination of optical and radar data, compared to 50 m3 ha-1 (30%) for the best single-sensor case in this study. In conclusion, the results indicate that the accuracy of forest variable estimations was substantially improved by using multisensor data. FOR. SCI. 49(3):409–418.