Modeling density-related Iodgepole pine height growth, using Czarnowski's stand dynamics theory

1993 ◽  
Vol 23 (12) ◽  
pp. 2499-2506 ◽  
Author(s):  
C J Cieszewski ◽  
I.E. Bella

This paper presents a new density-dependent height-growth model for lodgepole pine (Pinuscontorta var. latifolia Engelm.) in Alberta. It predicts stand top height growth as a function of present top height, breast height age, and density. The model is an extension of Czarnowski's stand dynamics theory, using an iterative height increment model with variable site and density components. Using 946 annual growth periods from permanent sample plots, the calibration shows a good fit and simulates reasonable values, even beyond the database.

2004 ◽  
Vol 19 (3) ◽  
pp. 154-159 ◽  
Author(s):  
G. Geoff Wang ◽  
Shongming Huang ◽  
David J. Morgan

Abstract Based on the provincial stem analysis and permanent sample plot (PSP) data of 1,580 felled dominant and codominant trees, height growth patterns of lodgepole pine were compared among the three major natural subregions [Sub-Alpine (SAL), Upper Foothills (UFH), and Lower Foothills (LFH)] in Alberta. The comparison used the ratio of heights at 70 and 30 years of breast height age (Z ratio) as a quantitative measure of height growth pattern (i.e., the response variable), site index (height at breast height age of 50 years) as the covariate, and natural subregion as the factor. Results indicated that: (1) the height growth pattern in the SAL natural subregion was significantly different from other natural subregions; and (2) no significant differences in height growth pattern were found between other natural subregions. Two polymorphic height and site index curves were developed: one for the SAL natural subregion and the other for the UFH and LFH natural subregions. Comparisons between the two curves and the previously developed provincial curve indicated that, for the same site index, trees in the SAL subregion grow consistently slower after 50 years. When the provincial height and site index curve was applied to the SAL natural subregion, large differences (≤14%) in gross volume estimation were found. However, volume estimation differences were very small (<2%) when the provincial curve was applied to the other two natural subregions. It is recommended that the natural subregion-based curves should be used for predicting lodgepole pine site index or height at any age in the SAL natural subregion. West. J. Appl. For. 19(3):154–159.


1995 ◽  
Vol 25 (5) ◽  
pp. 767-776 ◽  
Author(s):  
Brian J. Palik ◽  
Kurt S. Pregitzer

Retrospective studies of forest stand dynamics may rely on estimates of tree ages. In some of these studies, trees are aged near the stem base, while in other studies trees may be aged at breast height. An age correction may be added to breast-height ages in an attempt to account for average time to reach breast height and thus provide better estimates of total ages. Aging at breast height can provide estimates of stem and stand ages that are sufficient and appropriate for many studies of stand dynamics, for example, those focusing on the dynamics of canopy recruitment. However, the various aging methodologies will provide similar interpretations of actual stand age structures only if early height growth rates are not variable among stems, an assumption not likely to be true. Thus, aging at breast height, with or without a correction factor, may be inappropriate in studies that rely on accurate determination of tree establishment times. In the present study, variability of early height growth rates for several tree species common to Populusgrandidentata Michx. forests is quantified by determining the number of years to reach breast height. Interpretations of stand age structures and dynamics are made based on total tree ages, breast-height ages, and corrected breast-height ages. The results are compared to explore the implications of ignoring variability in early height growth rates when interpreting development of the stands. For the study populations, early height growth rates were highly variable. Some variability was accounted for by differences in understory tolerance, establishment times, and regenerative modes. Intolerant species establishing early grew faster than more tolerant, later establishing species. Sprout-origin stems grew faster, and had much less variable growth rates, than did seed-origin stems. In the understory, hardwood regeneration grew faster than pine regeneration. Even after accounting for these factors, early height growth rates were still variable. Within replicate plots, cumulative establishment distributions based on breast-height ages always differed from those based on total ages, leading to different interpretations of stand age structures. Cumulative establishment distributions based on breast-height ages corrected for aging height differed 44% of the time from those based on total ages. The timing of understory reinitiation, an important dynamic in even-aged forests, was determined using the three aging methods and compared. The timing of understory reinitiation based on breast-height ages differed significantly from that derived using total ages, while that derived using corrected breast-height ages did not differ from the latter. These results suggest that interpretations of stand age structures and past dynamics based on breast-height ages should be viewed cautiously if the objectives of a study require accurate estimates of tree establishment times.


1983 ◽  
Vol 13 (5) ◽  
pp. 972-978 ◽  
Author(s):  
A. J. Thomson ◽  
R. B. Smith

Relative height and diameter values of 22-year-old western hemlock trees (Tsugaheterophylla (Raf.) Sarg.) were normally distributed, with a constant standard deviation from year to year. Ranking of individual trees in the distribution changed with time, presumably because the root systems encountered successively more favourable or unfavourable microsites. Competition effects were detectable on height and diameter at breast height (dbh), although these effects were considerably masked by the microsite effect. Dwarf mistletoe (Arceuthobiumtsugense (Rosendahl) G. N. Jones) effects were detectable on height growth, but not dbh growth. Height increment in a particular year varied in a pattern similar to February precipitation, while diameter increment varied in a pattern similar to March–May precipitation. This may account for the observation that the degree of correlation of height and diameter increments in a particular year varied from low to high.


1979 ◽  
Vol 9 (1) ◽  
pp. 76-81 ◽  
Author(s):  
W. J. Bloomberg ◽  
G. W. Wallis

Total height, annual height increment, annual diameter at breast height (dbh) increment, ratio of total height to dbh, and ratio of annual height increment to annual dbh increment were assessed as indicator variables for estimating growth reduction associated with Phellinusweirii root rot of Douglas-fir (Pseudotsugamenziesii). Generally, height variables were more sensitive indicators than dbh. Total height by 2-cm-dbh classes, ratio of total height to dbh, and ratio of annual height increment to annual dbh increment were more sensitive and less variable than the other indicators. Ratio of total height to dbh was a more consistent and sensitive indicator of growth reduction than all other variables. Application of this ratio in estimating height growth reduction in three plantations indicated reductions in infected trees of 1 to 8 m over periods of 2 to 24 years, averaging 0.9 to 1.7% annually.


2009 ◽  
Vol 39 (1) ◽  
pp. 180-192 ◽  
Author(s):  
Thompson K. Nunifu

In this study, compatible height and diameter increment models were fitted for lodgepole pine ( Pinus contorta Dougl. ex Loud. var. latifolia Engelm.), trembling aspen ( Populus tremuloides Michx.), and white spruce ( Picea glauca (Moench) Voss), using the relationship between diameter and height growth. It was assumed that tree diameter increment is directly proportional to height increment, and the proportionality constant is a function of competition and site productivity. The results showed that the fit statistics are comparable with results of other studies, with adjusted R2 ranging from 30% to 50%. A validation test of the models, using independent permanent sample plots data, showed that the short-term predictions of the models for both pure and mixedwood stands are fairly unbiased. The models also gave reasonable average height growth and diameter growth trajectories for pure stands of the three species and also projected long-term mixedwood (aspen – white spruce mixture) volume growth dynamics reasonably well. The models also projected reasonably well (i) the effect of increasing initial stem density on average diameter and height, and (ii) the stand volume compared with an older version the Mixedwood Growth Model (ver. 2000A). It was concluded that explicitly linking tree height and diameter increment models does not only have a solid ecological basis, but it also results in a compatible prediction of tree growth and stand dynamics.


1999 ◽  
Vol 29 (9) ◽  
pp. 1445-1448 ◽  
Author(s):  
Mark R Fulton

Relationships between tree height and diameter at breast height were described for 15 species across a range of sites in eastern Texas using a two-parameter equation. Maximum height varied significantly from site to site within a species, but the ratio of initial slope to maximum height was generally constant. Sites favoring tall trees of one species tended to favor tall trees of all species, especially among species found in the overstory. The greatest rates of height growth for a given diameter at breast height increment were found among some midstory and understory species.


1999 ◽  
Vol 29 (2) ◽  
pp. 252-259 ◽  
Author(s):  
K I Mallett ◽  
WJA Volney

Growth of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) trees infected with Armillaria ostoyae (Romagn.) Herink growing in disease centres were compared with the growth of uninfected trees from two stands in west-central Alberta. Sample trees were measured (height, diameter at breast height, and height to live crown) and disks removed for stem analysis. The standing wood volumes inside disease centres of the two sites were 54 and 15% of the volume in surrounding stands. There were no significant differences in height or diameter at breast height between infected and uninfected trees. Expected growth rates determined by stem analysis revealed, however, that there were conservative losses of 43% in annual volume increment, 32% in specific volume increment, and 23% in height increment. The pattern of stem growth of infected individuals was that typically found in open-grown trees, in marked contrast to the pattern found in uninfected trees growing outside the disease centre. Tree growth chronologies suggested that disease centres were present early in the stands' development as trees grew rapidly before they became infected; however, the characteristic open-grown pattern of trees found in disease centres did not change after they became infected.


1982 ◽  
Vol 58 (3) ◽  
pp. 131-135 ◽  
Author(s):  
I. E. Bella ◽  
J. P. De Franceschi

An operational thinning in a 25-year-old lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) stand in Alberta resulted in nearly a 50% increase in diameter at breast height (dbh) and height increment in the last 5 years. Initial stand density had no effect on dbh increment beyond that of initial tree size. The release effect extended throughout the narrow (around 1.5 m) leave strips. Mortality continued to occur at about the same rate in both treated and untreated plots, thus reducing the need for follow-up selective thinning. Although the treated area had much lower stand volumes, it has a faster growth rate and may catch up or even surpass the untreated area in merchantable yield at harvest.


BMJ Open ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. e035785
Author(s):  
Shukrullah Ahmadi ◽  
Florence Bodeau-Livinec ◽  
Roméo Zoumenou ◽  
André Garcia ◽  
David Courtin ◽  
...  

ObjectiveTo select a growth model that best describes individual growth trajectories of children and to present some growth characteristics of this population.SettingsParticipants were selected from a prospective cohort conducted in three health centres (Allada, Sekou and Attogon) in a semirural region of Benin, sub-Saharan Africa.ParticipantsChildren aged 0 to 6 years were recruited in a cohort study with at least two valid height and weight measurements included (n=961).Primary and secondary outcome measuresThis study compared the goodness-of-fit of three structural growth models (Jenss-Bayley, Reed and a newly adapted version of the Gompertz growth model) on longitudinal weight and height growth data of boys and girls. The goodness-of-fit of the models was assessed using residual distribution over age and compared with the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). The best-fitting model allowed estimating mean weight and height growth trajectories, individual growth and growth velocities. Underweight, stunting and wasting were also estimated at age 6 years.ResultsThe three models were able to fit well both weight and height data. The Jenss-Bayley model presented the best fit for weight and height, both in boys and girls. Mean height growth trajectories were identical in shape and direction for boys and girls while the mean weight growth curve of girls fell slightly below the curve of boys after neonatal life. Finally, 35%, 27.7% and 8% of boys; and 34%, 38.4% and 4% of girls were estimated to be underweight, wasted and stunted at age 6 years, respectively.ConclusionThe growth parameters of the best-fitting Jenss-Bayley model can be used to describe growth trajectories and study their determinants.


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