Climate sensitive growth models for predicting diameter growth of western Canadian boreal tree species

2020 ◽  
Author(s):  
Felix O Oboite ◽  
Philip G Comeau
Keyword(s):  
Interspecific Competition ◽  
Tree Species ◽  
Growth Models ◽  
White Spruce ◽  
Tree Size ◽  
Diameter Growth ◽  
Growth Responses ◽  
Individual Tree ◽  
Negative Effect ◽  
Frost Free Period

Abstract In the face of anticipated climate change, growth models require modifications to effectively model likely future growth and survival of trees and stands. To support incorporation of climate effects in the Mixedwood Growth Model (MGM), we developed climate-sensitive mixed effects models for lodgepole pine (Pinus contorta Douglas ex Loudon), jack pine (Pinus banksiana Lamb.), trembling aspen (Populus tremuloides Michx.), balsam poplar (Populus balsamifera L.) and white spruce (Picea glauca (Moench) Voss), and examined how tree size, intra- and interspecific competition and climate will influence individual-tree diameter growth. Remeasurement data from permanent growth and yield sample plots from across the western Canadian boreal forest were used for this study. Based on the model that we developed, tree size, competition and climate had varying effects on growth, among tree species. Although intraspecific competition had a stronger negative effect on growth for deciduous and white spruce trees, interspecific competition had a stronger negative effect on the growth of pine. Deciduous trees growing in stands having longer frost-free period experienced an increase in growth but a negative effect of frost-free period was observed for conifers. In addition, higher moisture was found to increase tree growth, but the influence of available moisture on growth was dependent on competition. Overall, these results suggest that, under climate warming, between-species differences in growth responses will contribute to our understanding of the stand dynamics in the western boreal region of Canada. Climate sensitive growth models developed in this study will be useful in the recalibration of MGM and other individual-tree models, and predictions will contribute to better-informed decisions about silvicultural treatments for these economically important boreal tree species.

scholarly journals Individual Tree Diameter Growth Models of Larch–Spruce–Fir Mixed Forests Based on Machine Learning Algorithms

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 187 ◽  
Author(s):  
Qiangxin Ou ◽  
Xiangdong Lei ◽  
Chenchen Shen
Keyword(s):  
Machine Learning ◽  
Tree Growth ◽  
Growth Models ◽  
Tree Size ◽  
Diameter Growth ◽  
Individual Tree ◽  
Mixed Forests ◽  
Tree Diameter ◽  
Individual Tree Growth ◽  
The Individual

Individual tree growth models are flexible and commonly used to represent growth dynamics for heterogeneous and structurally complex uneven-aged stands. Besides traditional statistical models, the rapid development of nonparametric and nonlinear machine learning methods, such as random forest (RF), boosted regression tree (BRT), cubist (Cubist) and multivariate adaptive regression splines (MARS), provides a new way for predicting individual tree growth. However, the application of these approaches to individual tree growth modelling is still limited and short of a comparison of their performance. The objectives of this study were to compare and evaluate the performance of the RF, BRT, Cubist and MARS models for modelling the individual tree diameter growth based on tree size, competition, site condition and climate factors for larch–spruce–fir mixed forests in northeast China. Totally, 16,619 observations from long-term sample plots were used. Based on tenfold cross-validation, we found that the RF, BRT and Cubist models had a distinct advantage over the MARS model in predicting individual tree diameter growth. The Cubist model ranked the highest in terms of model performance (RMSEcv [0.1351 cm], MAEcv [0.0972 cm] and R2cv [0.5734]), followed by BRT and RF models, whereas the MARS ranked the lowest (RMSEcv [0.1462 cm], MAEcv [0.1086 cm] and R2cv [0.4993]). Relative importance of predictors determined from the RF and BRT models demonstrated that the competition and tree size were the main drivers to diameter growth, and climate had limited capacity in explaining the variation in tree diameter growth at local scale. In general, the RF, BRT and Cubist models are effective and powerful modelling methods for predicting the individual tree diameter growth.

scholarly journals Growth rates of valuable tree species in secondary tropical montane cloud forests in Mexico: influence of tree size, crown position and competition

2019 ◽  
Vol 25 (3) ◽  
Author(s):  
Magdaleno Mendoza-Hernández ◽  
Patricia Gerez-Fernández ◽  
Silvia Purata-Velarde ◽  
Tarin Toledo-Aceves
Keyword(s):  
Growth Rates ◽  
Tree Species ◽  
Basal Area ◽  
Selective Logging ◽  
Tree Size ◽  
Diameter Growth ◽  
Timber Species ◽  
Cloud Forests ◽  
Negative Effect ◽  
Tropical Montane Cloud Forests

Tropical montane cloud forests (TMCF) are under severe threat from deforestation, fragmentation and degradation. Several tree species are harvested and commercialized by local communities through unplanned selective logging. Lack of information regarding the growth rates of the most economically valuable timber species hampers the design of effective sustainable management schemes for TMCF. The objective of this study was to determine the diameter growth rates and evaluate the influence of tree size, crown class and neighbouring tree basal area on the growth of common and valuable TMCF timber species. Annual diameter growth was measured during two years in 60 trees (10 to 45 cm in diameter at breast height; dbh) each of Alnus acuminata, Liquidambar styraciflua and Quercus xalapensis, located in two unmanaged secondary TMCF sites in Veracruz, Mexico. High diameter growth rates (centimeter per year [cm yr-1]; mean ± SE) were recorded in the three species; the highest was recorded in A. acuminata (1.62 cm yr-1 ± 0.08 cm yr-1), followed by Q. xalapensis (0.91 cm yr-1 ± 0.07 cm yr-1) and L. styraciflua (0.71 cm yr-1 ± 0.08 cm yr-1). Diameter growth rate was inversely related to the basal area of the neighbouring trees, indicating a negative effect of competition in the three species. Dominant trees had higher growth rates than supressed trees in the three species. The high growth rates recorded in forests with no previous management and the negative effect of basal area of neighbouring trees support the potential for silvicultural management in secondary TMCF.

scholarly journals Precommercial Thinning Increases Spruce Yields in Boreal Mixedwoods in Alberta, Canada

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 412
Author(s):  
Ivan Bjelanovic ◽  
Phil Comeau ◽  
Sharon Meredith ◽  
Brian Roth
Keyword(s):  
Growth Models ◽  
Growth And Yield ◽  
Diameter Growth ◽  
Growth Responses ◽  
Projection System ◽  
Precommercial Thinning ◽  
Thinning Intensity ◽  
Boreal Mixedwoods ◽  
Using Data ◽  
Mixedwood Stands

A few studies in young mixedwood stands demonstrate that precommercial thinning of aspen at early ages can improve the growth of spruce and increase stand resilience to drought. However, information on tree and stand responses to thinning in older mixedwood stands is lacking. To address this need, a study was initiated in 2008 in Alberta, Canada in 14 boreal mixedwood stands (seven each at ages 17 and 22). This study investigated growth responses following thinning of aspen to five densities (0, 1000, 2500, 5000 stems ha−1 and unthinned (control)). Measurements were collected in the year of establishment, and three and eight years later. Mortality of aspen in the unthinned plots was greater than in the thinned plots which were not significantly different amongst each other. Eight years following treatment, aspen diameter was positively influenced by thinning, while there was no effect on aspen height. The density of aspen had no significant effect on the survival of planted spruce. Spruce height and diameter growth increased with both aspen thinning intensity and time since treatment. Differentiation among treatments in spruce diameter growth was evident three years from treatment, while differentiation in height was not significant until eight years following treatment. Yield projections using two growth models (Mixedwood Growth Model (MGM) and Growth and Yield Projection System (GYPSY)) were initialized using data from the year eight re-measurements. Results indicate that heavy precommercial aspen thinning (to ~1000 aspen crop trees ha−1) can result in an increase in conifer merchantable volume without reducing aspen volume at the time of harvest. However, light to moderate thinning (to ~2500 aspen stems ha−1 or higher), is unlikely to result in gains in either deciduous or conifer merchantable harvest volume over those of unthinned stands.

scholarly journals Diameter Growth in Even- and Uneven-Aged Northern Hardwoods in New Hampshire Under Partial Cutting

2004 ◽  
Vol 21 (3) ◽  
pp. 160-163 ◽  
Author(s):  
William B. Leak
Keyword(s):  
New Hampshire ◽  
Diameter Growth ◽  
Growth Responses ◽  
Partial Cutting ◽  
Individual Tree ◽  
Increment Core ◽  
Northern Hardwood ◽  
Important Concern ◽  
Understory Trees ◽  
Baseline Diameter

Abstract One important concern in the conversion of even-aged stands to an uneven-aged condition through individual-tree or small-group cutting is the growth response throughout the diameter-class distribution, especially of the understory trees. Increment-core sampling of an older, uneven-aged northern hardwood stand in New Hampshire under management for about 50 years established the baseline diameter-growth responses of the sapling, pole, and sawtimber strata. Growth responses of the poletimber and sawtimber in a 70-year-old even-aged stand were comparable to the uneven-aged stand after an initial partial cutting treatment; growth of the understory began approaching comparable rates after the second entry about 25 years after the first cut. North. J. Appl. For. 21(3):160–163.

scholarly journals Use of Plastic Shelters for Low-Cost Establishment of Street Trees

1996 ◽  
Vol 20 (2) ◽  
pp. 85-89 ◽  
Author(s):  
R. H. Jones ◽  
A. H. Chappelka ◽  
D. H. West
Keyword(s):  
Tree Species ◽  
Low Cost ◽  
Height Growth ◽  
Diameter Growth ◽  
Industrial Park ◽  
Growth Responses ◽  
Urban Settings ◽  
Planting Methods ◽  
Survival And Growth ◽  
One Year

Abstract One-year-old seedlings of 11 commonly used urban shade tree species were protected with plastic shelters to determine effects on survival and growth. Additional seedlings were planted in the cities of Auburn and Opelika, Alabama, to determine seedling performance in actual urban settings and to estimate incidence of vandalism in five urban settings. Shelters increased survival in four species and height growth in seven. Diameter growth responses were mixed. During the first 13 months after planting, only 3% of the seedlings in the cities were damaged by people. However, 20% of the shelters were vandalized at least once. Vandalism rates for shelters were greatest (37-44%) in neighborhoods of privately and publicly owned homes; intermediate (20%) in recreational parks, and lowest (4-6%) in undeveloped or industrial park areas. Installation of each tree with its shelter cost $2.78 (excluding labor) and required 20-25 minutes of labor. Tree shelters show promise as a low-cost alternative to more expensive planting methods, especially in undeveloped portions of cities. South. J. Appl. For. 20(2):85-89.

scholarly journals Individual-Tree Diameter Growth Models for Mixed Nothofagus Second Growth Forests in Southern Chile

Forests ◽  
2017 ◽  
Vol 8 (12) ◽  
pp. 506 ◽  
Author(s):  
Paulo Moreno ◽  
Sebastian Palmas ◽  
Francisco Escobedo ◽  
Wendell Cropper ◽  
Salvador Gezan
Keyword(s):  
Growth Models ◽  
Diameter Growth ◽  
Southern Chile ◽  
Individual Tree ◽  
Tree Diameter ◽  
Second Growth ◽  
Diameter Growth Models

scholarly journals Individual Tree Diameter and Height Growth Models for 30 Tree Species in Mixed-Species and Uneven-Aged Forests of Mexico

Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 429
Author(s):  
Jaime Briseño-Reyes ◽  
José Javier Corral-Rivas ◽  
Raúl Solis-Moreno ◽  
Jaime Roberto Padilla-Martínez ◽  
Daniel José Vega-Nieva ◽  
...  
Keyword(s):  
Tree Species ◽  
Forest Ecosystems ◽  
Growth Models ◽  
Mixed Forest ◽  
Tree Height ◽  
Height Growth ◽  
Site Factors ◽  
Individual Tree ◽  
Species Specific ◽  
Total Tree

Lack of knowledge of individual tree growth in species-rich, mixed forest ecosystems impedes their sustainable management. In this study, species-specific models for predicting individual diameter at breast height (dbh) and total tree height (h) growth were developed for 30 tree species growing in mixed and uneven-aged forest stands in Durango, Mexico. Growth models were also developed for all pine, all oaks, and all other species of the genus Arbutus (strawberry trees). A database of 55,158 trees with remeasurements of dbh and h of a 5-year growth period was used to develop the models. The data were collected from 217 stem-mapped plots located in the Sierra Madre Occidental (Mexico). Weighted regression was used to remove heteroscedasticity from the species-specific dbh and h growth models using a power function of the tree size independent variables. The final models developed in the present study to predict dbh and total tree height growth included size variables, site factors, and competition variables in their formulation. The developed models fitted the data well and explained between 98 and 99% and of the observed variation of dbh, and between 77 and 98% of the observed variation of total tree height for the studied species and groups of species. The developed models can be used for estimating the individual dbh and h growth for the analyzed species and can be integrated in decision support tools for management planning in these mixed forest ecosystems.

The interactive effect of competition and climate on growth of boreal tree species in western Canada and Alaska

2020 ◽  
Vol 50 (5) ◽  
pp. 457-464 ◽  
Author(s):  
Felix O. Oboite ◽  
Philip G. Comeau
Keyword(s):  
Interspecific Competition ◽  
Tree Growth ◽  
Intraspecific Competition ◽  
Tree Species ◽  
Basal Area ◽  
White Spruce ◽  
Jack Pine ◽  
Western Canada ◽  
Trembling Aspen ◽  
Balsam Poplar

Understanding interactions between competition and climate in relation to their effects on individual tree growth is crucial to the development of climate-sensitive growth models required for modelling boreal forest succession in a changing climate. We used data from permanent growth and yield sample plots in western Canada and Alaska to investigate the impact of competition within a regional gradient of climatic conditions for lodgepole pine (Pinus contorta Douglas ex Loudon), jack pine (Pinus banksiana Lamb.), trembling aspen (Populus tremuloides Michx.), balsam poplar (Populus balsamifera L.), white spruce (Picea glauca (Moench) Voss), and black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.). We characterized the effects of competition (basal area of spruce–fir, deciduous, and pine trees larger than the focal tree) and climate (mean annual temperature and precipitation) and their interactions on basal area growth of individual trees using linear mixed-effects models. Our results indicated that intraspecific competition had stronger effects on growth than interspecific competition and climate. Moreover, significant interactions between intraspecific competition and climate suggest that an increase in intraspecific competition will lead to a reduction in tree growth for warmer regions (lodgepole pine, trembling aspen, balsam poplar, and white spruce) and wetter regions (jack pine). The manner in which interspecific competition altered tree growth responses to climate was variable, depending on tree species and competition type. These results indicate that the relationships between growth and climate may differ according to the degree of competition and the structure of the stand.

Individual-tree diameter growth models for quantifying within-stand response to nitrogen fertilization

1990 ◽  
Vol 20 (8) ◽  
pp. 1149-1155 ◽  
Author(s):  
Bahman Shafii ◽  
James A. Moore ◽  
James D. Newberry
Keyword(s):  
Growth Models ◽  
Stand Density ◽  
Simulation Models ◽  
Diameter Growth ◽  
Individual Tree ◽  
Diameter Increment ◽  
Prognosis Model ◽  
Using Data ◽  
Individual Trees ◽  
Northern Idaho

Diameter-increment models for nitrogen-fertilized stands were developed using data from permanent research plots in northern Idaho. The equations partially resembled PROGNOSIS model diameter growth formulations. Results indicated that both initial tree size and initial stand density produced significant interactions with treatment to explain an individual tree's response to fertilization. Larger trees in a stand showed more fertilization response than smaller trees. Furthermore, individual trees in low-density stands showed more fertilization response than those growing in high-density stands. These diameter increment predictive equations were formulated to be compatible with individual-tree distance-independent simulation models.

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