bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatial Optimization for Wildlife and Timber in Managed Forest Ecosystems
Authors: Hof John G. , Joyce Linda A. 
Published: April 2024

Abstract
This paper presents several nonlinear formulations for land allocation that optimize spatial layout for a single time period and that have the property that the number of choice variables increases linearly with the level of spatial resolution. Two nonlinear models are presented: one that accounts for spatial patterns with a cellular grid, and an alternative that uses geometric shapes. The formulations account for four criteria important to wildlife: the amount of edge, the juxtaposition of different habitat types for cover versus feeding needs, the dispersal distance between favorable habitats, and the minimum size of a patch of habitat. Case examples demonstrate the selection of different sizes of cuts as well as different spatial distributions of the cuts over the landscape, in response to different habitat needs for several species of wildlife. Sensitivity analyses were performed on alternative formulations and objective function coefficients. These model formulations are initial exploratory efforts, and extensions to this study are identified. For. Sci. 38(3):489-508.
GCA Variance Components in 36 Pinus sylvestris L. Full-Sib Families Cultivated at Five Nutrient Levels in a Growth Chamber
Authors: Jonsson Alena , Dormling Ingegerd , Eriksson Gösta , Norell Lennart 
Published: April 2024

Abstract
Seedlings belonging to 36 families from a partial diallel mating between 11 parents of Scots pine (Pinus sylvestris L.) were cultivated for three growth periods in growth chambers at five different nutrient levels in the range 5-45 mg N/l. The relation between N:K:P was always 100:65:13. Several growth, growth component, and quality characters were assessed, mainly during the third growth period. ANOVAs were run to estimate GCA and SCA variance components at each treatment level and on pooled data from all five or the four higher nutrient treatments. In the two latter the interaction GCA x nutrient treatment variance component was also estimated. For most growth and growth component characters, the highest values of GCA variance component were found at the intermediate nutrient treatments (25 and 35 mg N/l). This phenomenon was less pronounced for quality characters. The SCA was in most cases of less importance than the GCA. ANOVAs based on pooled data from all treatments resulted in GCA x treatment variance components which were mostly a few times smaller than the GCA variance component. This interaction became negligible when the lowest nutrient treatment was dropped from the analyses. For. Sci. 38(3):575-593.
Predicting Crown-Height Increment for Thinned and Unthinned Loblolly Pine Plantations
Authors: Short III E. Austin , Burkhart Harold E. 
Published: April 2024

Abstract
Several nonlinear, individual tree crown-height increment equations were tested for their ability to predict annual crown-height increment in thinned and unthinned loblolly pine plantations. The selected model contained tree height (HT), tree crown ratio (CR) raised to the one-half power, age (A), and a measure of competition. The distance-dependent and the distance-independent models were the same form; however, the competition index (CI) in the distance-dependent model was replaced by the ratio of quadratic mean diameter to tree dbh (DR) for the distance-independent model.
The individual-tree increment models were used as a basis for a stand-level crown-height increment model. The independent variables were collapsed to stand-level statistics; the model contained average height of dominant and codominant trees (HD), average crown ratio (R), and age (A). Unlike the individual-tree models, raising the average crown ratio to 0.5 did not improve the fit.
Hypothesis tests revealed that thinning, both its intensity and the elapsed time since its occurrence, had a significant effect on crown-height increment. A thinning variable, T, which accounted for thinning intensity and the interval since thinning, was developed and incorporated into the final individual-tree and stand-level increment models. Predictions of crown-height increment were improved using models with the T variable as compared to those with no thinning allowance. For. Sci. 38(3):594-610.
Interaction of Virulent Single-Gall Rust Isolates of Cronartium quercuum f. sp. fusiforme and Resistant Families of Loblolly Pine
Authors: Kuhlman E. George 
Published: April 2024

Abstract
Basidiospores derived from 6 virulent single-gall aeciospore isolates of Cronartium quercuum f. sp. fusiforme produced different frequencies of galls on half-sib progeny of 21 loblolly pine families. One family was immune to infection by 2 of the isolates (0% of seedlings with galls), but only moderately resistant (53% galls) to another isolate. Another family was susceptible to all 6 isolates (70-82% of seedlings with galls). The interactions between individual families and the 6 isolates suggest that there are at least 9 different patterns of relative susceptibility among these 21 pine families to the 6 isolates, based on percentage of seedlings with galls. The patterns suggest that there are a variety of resistance genes among these families providing a broad genetic base for field resistance. Gall length was not always related to relative resistance. Three resistant families, 151-791,152-60, and 11-41, had the shortest average gall lengths of 21, 26, and 27 mm, respectively. However, resistant family 10-5 had the greatest average gall length of 52 mm. For. Sci.: 38(3):641-651.
Competitive Interference Between Selected Herbaceous and Woody Plants and Pinus taeda L. During Two Growing Seasons Following Planting
Authors: Morris L. A. , Moss S. A. , Garbett W. S. 
Published: April 2024

Abstract
Interference between loblolly pine (Pinus taeda) seedlings and selected herbaceous (panicum grass, Panicum dichotomiflorum; coffeeweed, Sesbania exaltata; broomsedge, Andropogon spp.) and woody (sweetgum, Liquidambar styraciflua) competitors was evaluated during the first two growing seasons following planting on a loamy sand Coastal Plain site. Pine seedling growth was reduced by all competitors. During the first growing season, competition for water was the dominant factor affecting pine growth. Panicum grass, which most rapidly depleted available water in the soil surface, was the strongest competitor. Reductions in N, Ca, and K foliar concentrations were associated with reduced surface soil water availability in grass and coffeeweed plots during this period. On plots with less competitive broomsedge and sweetgum, only K and Ca concentrations of pine foliage were reduced. Fertilization with NPK or P alone had no affect on pine growth and had only a minor affect on pine foliage nutrient concentrations. Although differences in growth occurred among families, all families responded to competitor and fertilizer treatments in a similar manner. Competitors had less influence on seedling water use and nutrition during the second growing season. Although absolute differences in seedling size among competitor treatments increased, much of this was due to differences in seedling size at the start of the growing season. FOR. SCI. 39:166-187.
Age Trends in Genetic Parameters for Tree Height in a Nonselected Population of Loblolly Pine
Authors: Balocchi C. E. , Bridgwater F. E. , Zobel B. J. , Jahromi S. 
Published: April 2024

Abstract
Additive variance for height of loblolly pine (Pinus taeda L.) in Georgia was very low at younger ages (1 to 8) but rapidly increased thereafter. Nonadditive variance increased from ages 1 to 10 and then remained constant through age 26. The ratio of nonadditive variance to total genetic variance increased from 17% at age 1 to a maximum of 82% at age 6, and then declined to 20% at age 26.
Heritability values ranged from almost zero to approximately 0.75 with the lowest values occurring at very young ages and for within-family and individual-tree heritabilities. The largest values were associated mainly with family heritabilities and older ages. Almost all estimates of heritability exhibited similar trends; values were very low at early ages and a maximum value between ages 14 and 16. Narrow-sense heritabilities were near zero until approximately age 8, then they increased sharply through age 16 and declined at the final measurement age.
Finally, the coeffident of genetic prediction for tree height between juvenile ages (1 to 16) and the final measurement age for tree height, when based on the total genetic component (CGP_G), showed a nearly linear increase from age 1 to age 16. The maximum values for this parameter were those associated with full-sib family means and ranged from 0.13 at age 1 to 0.67 at age 16. The additive (CGP_A) and nonadditive (CGP_D) components of CGP_G followed the same patterns the additive and nonadditive variances followed. FOR. SCI. 39(2):231-251.
Growth and Nutrition of Hybrid Poplar in Response to Phosphorus, Zinc, and Gibberellic Acid Treatments
Authors: Teng Yuanxin , Timmer Victor R. 
Published: April 2024

Abstract
Phosphorus-induced growth inhibition in poplar hybrid shoots in a greenhouse trial was corrected by treatment with either soil-incorporated Zn fertilizer or leaf spray of gibberellic acid (GA). Increasing P applications depressed plant growth. Zinc added alone failed to stimulate growth, but when combined Zn with P it increased total biomass production by 27-41%. GA spray increased height and dry weight of shoot by 32% and 11%, respectively, at the expense of root growth without increasing total biomass. Foliar P and Zn concentrations were unchanged by GA treatment, but N concentrations were reduced, probably because of dilution. Although GA may be useful for stimulating shoot elongation, it may not be practical for correcting P-induced Zn disorders in hybrid poplar culture. FOR. SCI. 39(2):252-259.
Disaggregating Stand Volume Growth to Individual Trees
Authors: Zhang Lianjun , Moore James A. , Newberry James D. 
Published: April 2024

Abstract
A disaggregation function, relative size-growth (RSG), was proposed and developed for interior Douglas-fir (Pseudotsuga menziesii var. glauca [Beissn] Franco) to distribute stand volume growth to a list of individual trees. The RSG function was formulated as a quadratic equation relating relative tree growth to relative tree size in a stand. The shape of the RSG function was linear, convex, or concave depending on initial stand conditions and structure. A recursive system of equations was developed to predict the three coefficients of the RSG function using initial stand density, mean tree size, and coefficient of variation of tree size distribution as predictor variables. This disaggregation function determines within-stand growth of individual trees and simulates stand development and dynamics. The RSG function provides a biologically based link between whole-stand and individual tree resolution models. FOR. SCI. 39(2):295-309.
Modeling Multiplicative Error Variance: An Example Predicting Tree Diameter from Stump Dimensions in Baldcypress
Authors: Parresol Bernard R. 
Published: April 2024

Abstract
In the context of forest modeling, it is often reasonable to assume a multiplicative heteroscedastic error structure to the data. Under such circumstances ordinary least squares no longer provides minimum variance estimates of the model parameters. Through study of the error structure, a suitable error variance model can be specified and its parameters estimated. This error model is used to construct a covariance matrix which in turn is used to form an estimated generalized least squares estimator of the forest model parameters. The theory is illustrated with data on baldcypress (Taxodium distichum [L.] Rich.). A multiple linear regression equation is developed for predicting diameter at 3 m from solid-wood stump diameter (i.e., diameter inside the fluting) and stump height. By modeling the error structure, standard errors on three of the four coefficients from the tree diameter-stump dimensions regression were reduced by 13 to 50%. The effect on prediction confidence intervals is graphically illustrated. For. Sci. 39(4):670-679.
An Integer Programming Approach for Spatially and Temporally Optimizing Wildlife Populations
Authors: Hof John , Bevers Michael , Joyce Linda , Kent Brian 
Published: April 2024

Abstract
This paper presents mixed integer linear programming formulations that optimize the spatial layout of management actions for providing wildlife habitat, over time. The formulations focus on wildlife growth and dispersal as a dynamic, probabilistic process. Habitat fragmentation/connectivity is thus modeled indirectly. Multiple timber age classes are accounted for as different wildlife habitat types, which define carrying capacity limitations that are tracked spatially. A variety of objective functions are specified, including ones based on piecewise-approximated nonlinear functions that relate wildlife populations to the probability of species viability. All of the formulations and objective functions are demonstrated with a case example. For. Sci. 40(1):177-191.
Measuring Net Investment and Productivity in Timber Production
Authors: Wear David N. 
Published: April 2024

Abstract
An index number approach is developed for measuring changes in inputs, outputs, and total factor productivity in a timber-producing sector. These methods are applied to timber production in the U.S. South for the period 1952 to 1985. Results suggest that development of the sector may be described by an adjustment phase between 1952 and 1962 and a growth phase between 1962 and 1985. Aggregate output grew during the latter period at an annual rate of 2.0% for the forest industry and 1.2% for all other private lands. Input growth was also strong for the industry reflecting expansion in both the area of timberland and the intensity of management. On other private lands, however, timberland and inputs showed steady declines. Output growth net of input growth shows that productivity grew at about 0.5% per year on the industry lands and 2.5% per year on other private lands. However, the strong productivity measure for the other private ownership likely reflects measurement error related to the classification of timberland. These results demonstrate the potential hazards of using either trends in timberland area or gross investment (planting) alone to assess the development of a timber-producing sector. For. Sci. 40(1):192-208.
Seasonal Physiology of Douglas-fir Saplings: Response to Microclimate in Stands of Tanoak or Pacific Madrone
Authors: Harrington Timothy B. , Pabst Robert J. , Tappeiner II J. C. 
Published: April 2024

Abstract
Plant water potential, leaf conductance, and photosynthesis of saplings of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) were monitored monthly in 1986 through 1988. The objective was to describe influences of microclimate (light, soil water, temperature, and relative humidity) associated with young stands of tanoak (Lithocarpus densiflorus [Hook. & Arn.] Rehd.) or Pacific madrone (Arbutus menziesii Pursh) on Douglas-fir physiology. Hardwood shade reduced photosynthetically active radiation to 20 to 38% of full sunlight; as a result, photosynthesis of Douglas-fir shaded by hardwoods was light-limited throughout the year. Soil water potentials (30-cm depth) in summer (July through September) averaged -0.64 MPa in the presence of hardwoods and - 0.23 MPa in their absence. Reduced soil water availability in the hardwood stand, coupled with elevated air temperatures and lower relative humidities, reduced photosynthesis of associated Douglas-fir. Stomatae neared complete closure at the following plant water potentials: -2.3 (tanoak), -2.5 (Douglas-fir), and -3.4 MPa (madrone). Although seasonal rates of photosynthesis did not vary greatly among the three species, specific water-use patterns were apparent. The abilities of species to minimize water stress were ranked as tanoak &gt; Douglas-fir &gt; madrone. For. Sci. 40(1):59-82.
Growth of Outplanted Lodgepole Pine Seedlings One Year After Inoculation with Plant Growth Promoting Rhizobacteria
Authors: Chanway C. P. , Holl F. B. 
Published: April 2024

Abstract
Four-month-old lodgepole pine seedlings were inoculated with plant growth promoting rhizobacteria (Bacillus polymyxa strain L6-16R) and outplanted at one interior site (Gavin Lake) and two coastal sites (University of British Columbia South Campus and Totem Field) in British Columbia. The percentage of seedlings that incurred overwinter injury and that survived 13 months after outplanting were not influenced by bacterial inoculation. At Totem Field, where growth of control seedlings was greatest, inoculation had an inhibitory effect on seedling performance. At South Campus, where growth of control seedlings was intermediate compared with seedlings at Totem Field and Gavin Lake, inoculation had a slight stimulatory effect on seedling performance, but bacterial effects were not significant. However, at Gavin Lake, where seedlings attained only 14% of the biomass of those grown at Totem Field, inoculated seedlings had significantly increased stem diameter (7%), root dry weight (32%), and shoot dry weight (33%). While the effects of site history and site quality were confounded in this study, these results suggest that inoculation of lodgepole pine with strain L6-16R may be useful for seedlings targeted for outplanting on relatively harsh or poorer quality sites, but less so for seedlings to be planted at higher quality sites. For. Sci. 40(2): 238-246.
Adaptedness of Noble Fir (Abies procera Rehd.) Beyond Its Northern Limit
Authors: Xie Chang Yi , Ying Cheng C. 
Published: April 2024

Abstract
The adaptedness of noble fir (Abies procera Rehd.) beyond its northern limit was examined at 12 locations distributed throughout the Maritime, Submaritime, and Subcontinental climates in south coastal British Columbia. Ten-year testing results demonstrated large site effects. Noble fir planted in the Maritime climate survived better, grew faster, entered the period of accelerated growth earlier, and maintained a higher growth rate. In the Maritime climate, the reforestation range of noble fir can be extended considerably north of its current natural distribution and to lower elevations. Low winter temperature and growing-season soil moisture appear to be the major environmental factors limiting the species' expansion into more continental climates, and these factors must be considered in planting site selection.
Provenance differences in both growth and survival were significant but small compared to site differences. Adaptive variation showed gentle geographic clines indicating that northern provenances were better adapted in the Maritime climate, whereas inland provenances were superior in the Submaritime climate. Lack of strong geographic patterns suggests that local environmental factors may be important to the adaptive variation of the species.
The test results suggest that introduction of noble fir to British Columbia should be limited to the Maritime region, and that northern provenances, such as French Butte, McKinley Lake, and Stevens Pass in Washington are the primary seed sources. For. Sci. 40(3):412-428.
Topographic Variation of Soil Nitrogen Dynamics at Walker Branch Watershed, Tennessee
Authors: Garten Charles T. , Huston Michael A. , Thoms Christopher A. 
Published: April 2024

Abstract
Understanding the spatial and temporal variability of soil nitrogen (N) transformations is central to quantifying the N dynamics and productivity of ecosystems. The objectives of this work were to examine spatial and temporal variation of soil N dynamics and to identify factors correlated with topographic variation in soil N dynamics in a forest watershed. Net N mineralization and net nitrification potential were measured by aerobic laboratory incubations of surface (0-7 cm) mineral soils. Principal components analysis was used to describe sampling sites across the watershed based on 13 site characterization variables. A topographic index used in hydrologic modeling, In (α/tan β), was calculated for each site as the natural logarithm of the ratio of the upslope drainage area per unit contour length (α) to the local slope angle (tan β). Soils from valley floors had greater total N concentrations, lower carbon-to-nitrogen (C:N) ratios, greater potential net nitrification, and greater microbial activity (as indicated by short-term urease assays) than soils from ridges. Mean net nitrification potential was 0.59 μg N g-1 d-1 in surface soils from valley floors and was &lt; 0.01 on ridges and slopes. The first principal component was related to the N and C properties of soils, leaf litter, and leaf fall at a site. The second principal component was related to forest stand composition. The topographic index was significantly correlated with important variables related to soil N dynamics. Once calibration data are derived, this index may be useful as a first approximation to total soil N concentrations and soil C:N ratios in forest watersheds because In (α/tan β) can be calculated from geographic information systems that contain topographic data. For. Sci. 40(3):497-512.
Random-Parameter Height/Age Models when Stand Parameters and Stand Age are Correlated
Authors: Lappi Juha , Malinen Juha 
Published: April 2024

Abstract
Height/age curves of dominant trees in a stand can be predicted using models containing random stand and tree parameters. If the population mean curve is estimated from the data where stand-specific parameters are correlated with stand age (e.g., because old stands are growing on poor sites), this correlation may cause biased estimates. The same bias problem occurs in traditional site index methods. It is shown how ordinary least squares estimates of tree specific parameters can be used for computing unbiased estimates of the population mean parameters and for estimating the relationship between stand parameters and stand age. The application of the estimated model several years after the data collection time is problematic because it should be known how the population changes over time. For. Sci. 40(4):715-731.
Note on the Relation Between Ring Widths and Basal Area Increments
Authors: Visser Hans 
Published: April 2024

Abstract
A primary aim of tree-ring analysis is to reconstruct the annual growth patterns of individual trees or groups of trees, and then derive growth models which allow for prediction of wood production. Tree growth is mostly measured as a series of annual ring widths. In practice, however, one is interested in annual basal area increments (BAIs). The calculation of BAIs is quite involved. One needs extra information in addition to ring widths: diameters measured at the thickest and thinnest sides of the tree and an estimate of bark width. In this note a summary of the relevant formulas is presented. For. Sci. 41(2):297-304.