Analyse qualitative des équations différentielles d'un modèle de croissance pour l'érablière à sucre

1987 ◽  
Vol 17 (7) ◽  
pp. 588-593
Author(s):  
Chun-Huor Ung ◽  
François Bertrand
Keyword(s):  
Sugar Maple ◽  
Basal Area ◽  
Department Of Energy ◽  
Model Parameters ◽  
Weibull Function ◽  
Sample Plot ◽  
Permanent Sample Plots ◽  
Modèle De Croissance ◽  
Mathematical Behavior ◽  
Qualitative Analyses

This paper describes a growth model based on the Weibull function. An estimation of the model parameters is made from data of 89 permanent sample plots provided by the Quebec Department of Energy and Resources. Sugar maple represents more than 75% of the total basal area in each sample plot. Qualitative analyses is used to study completely the mathematical behavior of the model.

Modèle de prédiction des essences feuillues et résineuses du Québec

1982 ◽  
Vol 12 (2) ◽  
pp. 232-239 ◽  
Author(s):  
Chhun-Huor Ung ◽  
Jean Beaulieu ◽  
Daniel Demers
Keyword(s):  
Prediction Model ◽  
Basal Area ◽  
Growth Conditions ◽  
The State ◽  
Department Of Energy ◽  
Forest Species ◽  
Permanent Sample Plots ◽  
Real Growth ◽  
Basic Characteristics ◽  
Softwood Species

This paper describes a prediction model adopted by the Department of Energy and Resources of Quebec to (i) update temporary sample plots and (ii) project into the future the state of permanent sample plots in Quebec forests. Predicting the growth of a forest species means predicting the state of this species in time. Three basic characteristics mark the state of a species in a given year: number of trees, their total basal area, and their total volume. To date, in Quebec, normal or empirical yield tables have been used to predict the state of some species in ideal or real growth conditions, but these yield tables apply only to pure or almost pure even-aged stands. The prediction model for hardwood and softwood species presented in this paper serves the same purpose as the yield tables; however, it differs from the yield tables in that it can predict the state of each hardwood or softwood species found in pure or mixed, even- or uneven-aged stands. The prediction model was validated for 19 species found in a pilot territory located in the Basse-Gatincau (southwestern Quebec). The paper terminates with a discussion on the limitation of the prediction model and the conditions for its use.

Present-day expansion of American beech in northeastern hardwood forests: Does soil base status matter?

2009 ◽  
Vol 39 (12) ◽  
pp. 2273-2282 ◽  
Author(s):  
Louis Duchesne ◽  
Rock Ouimet
Keyword(s):  
Acer Saccharum ◽  
Sugar Maple ◽  
Basal Area ◽  
Base Cation ◽  
Hardwood Forests ◽  
Fagus Grandifolia ◽  
Soil Base ◽  
Large Area ◽  
American Beech ◽  
Permanent Sample Plots

Recently, sugar maple ( Acer saccharum Marsh.) decline in northeastern North America has been regarded as a major factor structuring hardwood forests by favouring American beech ( Fagus grandifolia Ehrh.) in the understory of maple-dominated stands. To determine whether soil fertility differences associated with sugar maple decline may have promoted the expansion of American beech, we explored the relationships between the soil base status and the sapling and tree strata density and composition, using data from 426 permanent sample plots distributed throughout Quebec. Our results indicate that American beech is currently expanding in the sugar maple range of Quebec. The abundance and proportion of American beech in the sapling stratum are mainly associated with the proportion of American beech in the tree stratum, the relative basal area of dead sugar maple trees, and the base status of soils. In accordance with the many studies reporting on the high sensitivity of sugar maple to the acid–base status of soils and the decline of the sugar maple population, this study supports the hypothesis that soil base cation depletion, caused in part by atmospheric acid deposition, is among the main factors involved in the present-day expansion of American beech over a large area in Quebec.

scholarly journals Modeling tolerant hardwood sapling density and occurrence probability in the Acadian forests of New Brunswick, Canada: Results 14 years after harvesting

2021 ◽  
Vol 97 (02) ◽  
pp. 204-218
Author(s):  
Mohammed Henneb ◽  
Gaetan Pelletier ◽  
Mathieu Fortin ◽  
Nelson Thiffault ◽  
Marie-Andrée Giroux
Keyword(s):  
New Brunswick ◽  
Acer Saccharum ◽  
Sugar Maple ◽  
Basal Area ◽  
Fagus Grandifolia ◽  
Eastern Canada ◽  
American Beech ◽  
Permanent Sample Plots ◽  
Hardwood Species ◽  
Sapling Density

Natural forest regeneration after natural or anthropogenic disturbance is difficult to predict given its high variability. The process is poorly documented for commercial northern hardwood species in the Acadian forest of eastern Canada. Our objective was to identify the silvicultural, environmental, and ecological factors that best explain the variability in sapling density and occurrence of two commercial tolerant hardwood species in New Brunswick: American beech (Fagus grandifolia Ehrh.) and sugar maple (Acer saccharum Marsh.). Forty-three permanent sample plots were established in 2002 and measured before harvesting in 2004. Sapling density and occurrence were measured 14 years after harvesting. The results showed that the interactions between the species and the residual merchantable basal area and between the species and the percent of hardwoods in the original stand best explained the sapling density and occurrence variation of tolerant hardwoods. The sapling density of sugar maple increased with increasing merchantable residual basal area. However, the effect of this variable was not significant for the density of American beech saplings. The density and occurrence of tolerant hardwood saplings both increased along with the percent of hardwoods in the original stand. These results provide an improved understanding about tolerant hardwood regeneration dynamics in New Brunswick forests.

Exploring the Recruitment Dynamics of Sugar Maple and Yellow Birch Saplings into Merchantable Stems Following Harvesting in the Acadian Forest Region of New Brunswick, Canada

2021 ◽  
Author(s):  
Alex Noel ◽  
Jules Comeau ◽  
Salah-Eddine El Adlouni ◽  
Gaetan Pelletier ◽  
Marie-Andrée Giroux
Keyword(s):  
New Brunswick ◽  
Sugar Maple ◽  
Basal Area ◽  
Stem Density ◽  
Yellow Birch ◽  
Probability Of Occurrence ◽  
Silvicultural Treatment ◽  
Forest Region ◽  
Wide Range ◽  
Acadian Forest

The recruitment of saplings in forest stands into merchantable stems is a very complex process, thus making it challenging to understand and predict. The recruitment dynamics in the Acadian Forest Region of New Brunswick are not well known or documented. Our objective was to draw an inference from existing large scale routine forest inventories as to the different dynamics behind the recruitment from the sapling layer into the commercial tree size layer in terms of density and occurrence of sugar maple (Acer saccharum Marsh.) and yellow birch (Betula alleghaniensis Britt.) following harvesting, by looking at many factors on a wide range of spatial and temporal scales using models. Results suggest that the variation in density and probability of occurrence is best explained by the intensity of silvicultural treatment, by the merchantable stem density in each plot, and by the proportion of merchantable basal area of each group of species. The number of recruits of sugar maple and yellow birch stems tend be higher when time since last treatment increases, when mid to low levels of silvicultural treatment intensity were implemented, and within plots having intermediate levels of merchantable stem density. Lastly, our modeling efforts suggest that the probability of occurrence and density of recruitment of both species tend to increase while its share of merchantable basal area increases.

A comparison of vegetative cover and tree community structure in three forested Adirondack watersheds

1985 ◽  
Vol 15 (5) ◽  
pp. 881-889 ◽  
Author(s):  
Christopher S. Cronan ◽  
Marc R. DesMeules
Keyword(s):  
New York ◽  
Sugar Maple ◽  
New York State ◽  
Basal Area ◽  
Red Maple ◽  
Vegetative Cover ◽  
Cover Type ◽  
Tree Community ◽  
Standing Dead ◽  
Annual Biomass

The Integrated Lake–Watershed Acidification Study (ILWAS) was conducted using three forested watersheds (Panther, Sagamore, and Woods) in the central Adirondack Park of New York State. By comparing the biogeochemical behavior of these watersheds, the ILWAS investigators hoped to elucidate the major ecosystem parameters controlling the fate of strong acids introduced from the atmosphere to lake–watershed systems. The ILWAS vegetation research program was designed to compare the quantitative patterns of forest structure in these midelevation watersheds. Results showed that the ILWAS catchments contain closely related variants of the northern hardwood – spruce – fir complex of the Adirondack region. The dominant tree species in these watersheds are beech (Fagusgrandifolia Ehrh.), red spruce (Picearubens Sarg.), sugar maple (Acersaccharum Marsh.), red maple (Acerrubrum L.), and yellow birch (Betulaalleghaniensis Britt.). On an areal basis, the watersheds contain 57–88% hardwood cover type and 5–29% spruce–fir cover type. Mean live basal area values range from 22 to 30 m2 ha−1 between catchments, while standing dead basal area values range from 4 to 8 m2 ha−1. Mean live stem densities range from 1400 to 1700 stems ha−1. Mean aboveground biomass projections for the tree stratum in the three watersheds range from 143 to 199 Mt ha−1, while estimated aboveground annual biomass increments range from 4.1 to 5.3% of standing biomass.

scholarly journals Radar-based Bayesian estimation of ice crystal growth parameters within a microphysical model

2020 ◽  
Author(s):  
Robert S. Schrom ◽  
Marcus van Lier-Walqui ◽  
Matthew R. Kumjian ◽  
Jerry Y. Harrington ◽  
Anders A. Jensen ◽  
...  
Keyword(s):  
Vapor Deposition ◽  
Growth Parameters ◽  
Particle Density ◽  
Optimal Parameter ◽  
Number Concentration ◽  
Department Of Energy ◽  
The Arctic ◽  
Model Parameters ◽  
Growth Ratio ◽  
Radar Measurements

AbstractThe potential for polarimetric Doppler radar measurements to improve predictions of ice microphysical processes within an idealized model-observational framework is examined. In an effort to more rigorously constrain ice growth processes (e.g., vapor deposition) with observations of natural clouds, a novel framework is developed to compare simulated and observed radar measurements, coupling a bulk adaptive-habit model of vapor growth to a polarimetric radar forward model. Bayesian inference on key microphysical model parameters is then used, via a Markov chain Monte Carlo sampler, to estimate the probability distribution of the model parameters. The statistical formalism of this method allows for robust estimates of the optimal parameter values, along with (non-Gaussian) estimates of their uncertainty. To demonstrate this framework, observations from Department of Energy radars in the Arctic during a case of pristine ice precipitation are used to constrain vapor deposition parameters in the adaptive habit model. The resulting parameter probability distributions provide physically plausible changes in ice particle density and aspect ratio during growth. A lack of direct constraint on the number concentration produces a range of possible mean particle sizes, with the mean size inversely correlated to number concentration. Consistency is found between the estimated inherent growth ratio and independent laboratory measurements, increasing confidence in the parameter PDFs and demonstrating the effectiveness of the radar measurements in constraining the parameters. The combined Doppler and polarimetric observations produce the highest-confidence estimates of the parameter PDFs, with the Doppler measurements providing a stronger constraint for this case.

Canada's oldest permanent sample plots — thinning in white and red pine

1998 ◽  
Vol 74 (4) ◽  
pp. 606-616 ◽  
Author(s):  
Darwin Burgess ◽  
Craig Robinson
Keyword(s):  
Woody Debris ◽  
Basal Area ◽  
Wildlife Habitat ◽  
Red Pine ◽  
Major Influence ◽  
Residual Volume ◽  
Annual Increment ◽  
Permanent Sample Plots ◽  
Stand Management ◽  
Set Up

Two of the oldest permanent sample plots (PSPs) in Canada were set up at Petawawa, Ontario (45° 57′ N, 77° 34′ W) to examine the effect of thinning on the development of natural white (Pinus strobus L.) and red pine (Pinus resinosa Ait). Field data were collected periodically, starting in 1918 when the stand was 40 years old and continuing for 71 years. Six thinning treatments were completed, beginning in 1918, and then in 1933, 1941, 1959, 1969 and 1989. The intensity of thinning varied through time with 14, 27, 38, 8, 30, and 7% of the basal area removed. The sawlog volume mean annual increment for the thinned plot remained stable at about five m3 ha−1 yr−1, but the sawlog volume periodic annual increment for the control declined markedly during the last 10-year measurement period to less than 2 m3 ha−1 yr−1. The residual volume was higher in the control; but, if the harvested sawlog volume (264.5 m3 ha−1) was added to the residual sawlog volume (301.3 m3 ha−1) for PSP one, then the sawlog production on the thinned plot has been about the same and its residual volume concentrated on fewer, larger and more valuable trees. The level of natural mortality in the control plot (129.7 m3 ha−1 of sawlog volume) was greater than 10 times that in the thinned plot, thereby adding more coarse woody debris to improve wildlife habitat. These two approaches had a major influence on stand development. The approach used will depend on specific stand-level management objectives. Key words: white pine, red pine, natural stand management, shelterwood system, permanent sample plots.

scholarly journals EFEITO DA EXPLORAÇÃO DE IMPACTO REDUZIDO EM ALGUMAS ESPÉCIES DE SAPOTACEAE NO LESTE DA AMAZÔNIA

FLORESTA ◽  
2013 ◽  
Vol 43 (3) ◽  
pp. 395 ◽  
Author(s):  
Leonardo Pequeno Reis ◽  
José Natalino Macedo Silva ◽  
Pamella Carolline Marques Dos Reis ◽  
João Olegário Pereira de Carvalho ◽  
Waldenei Travassos de Queiroz ◽  
...  
Keyword(s):  
Rain Forest ◽  
Basal Area ◽  
Tree Density ◽  
The Other ◽  
Permanent Sample Plots ◽  
Structure And Dynamics ◽  
The Family ◽  
Commercial Species ◽  
Three New Species ◽  
Reduced Impact Logging

Avaliou-se o efeito da exploração de madeira, realizada em 1997, na estrutura e dinâmica de algumas espécies de Sapotaceae em uma Floresta Ombrófila Densa, no município de Moju, Pará (02º12’26”S e 48º48’14”W). De uma área de floresta de 1.050 ha, foram selecionados 200 hapara exploração seletiva de intensidade de 23 m3.ha-1. Nessa área, foram alocadas 22 parcelas permanentes de 0,5 ha, totalizando 11 ha amostrais, onde foram medidas todas as árvores com DAP ≥10 cm, nos anos de 1995 (antes da exploração), 1998 e 2010 (após exploração). Os parâmetros avaliados foram densidade (Da) e área basal (m2.ha-1). No período de 1995 a 2010, Sapotaceae apresentou uma redução significativa de 7,7% na densidade (p = 0,0147) e aumento na dominância em 1,4% (p = 0,7851). Nesse mesmo período, observou-se redução da densidade e dominância para Pouteria laurifolia (Gomes) Radlk. (66,7 e 50,6%), Pouteria macrocarpa (Mart.) D. Dietr. (25 e 29,4%), Micropholis acutangula (Ducke) Eyma (20 e 11%), Manilkara huberi (Ducke) A. Chev. (16,4 e 17,7%) e Manilkara paraensis (Huber) Standl. (12,5 e 31,4%). A espécie com maior valor comercial, M. huberi, não mostrou recuperação nesse parâmetro, porém houve ingresso de três novas espécies na população de Sapotaceae estudada.AbstractEffect of reduced impact logging in some sapotaceae species in the eastern amazon. Effect of logging, held in 1997, on structure and dynamics of some Sapotaceae species were evaluated in a dense tropical rain forest located in the municipality of Moju, Pará (02º 12’ 26” S e 48º 48’ 14” W). Two hundred ha out of 1,050 ha forest area were selectively logged for timber (23 m3ha-1 logging intensity) in 1997.Twenty-two 0.5 ha permanent sample plots (11 ha sample) were established and all trees with dbh ≥ 10 cm were identified and measured for dbh in 1995 (before logging), 1998 and 2010 (after logging). Parameters evaluated were Density (De) and Basal area (G-m2 ha-1). Sapotaceae presented a significant reduction of 7.7% on tree density (p=0.0147), and an dominance increase of 1.4% (p=0.7851). In the same period, decreases in density and basal area were observed to Pouteria laurifolia (Gomes) Radlk. (66.7 and 50.6%), Pouteria macrocarpa (Mart.) D. Dietr. (25 and 29.4%), Micropholis acutangula (Ducke) Eyma (20 and 11%), Manilkara huberi (Ducke) A. Chev. (16.4 and 17.7%) and Manilkara paraensis (Huber) Standl. (12.5 and 31.4%). The main commercial species M. Huberi did not recover its original density. On the other hand, three new species of the family were recorded in the focused period.Keywords: Forest management; Pouteria; Manilkara; Amazonian Forest.

Long-term impact of liming on growth and vigor of northern hardwoods

2011 ◽  
Vol 41 (6) ◽  
pp. 1295-1307 ◽  
Author(s):  
Robert P. Long ◽  
Stephen B. Horsley ◽  
Thomas J. Hall
Keyword(s):  
Acer Saccharum ◽  
Sugar Maple ◽  
Keystone Species ◽  
Basal Area ◽  
Fagus Grandifolia ◽  
Northern Hardwood ◽  
Crown Health ◽  
Lime Application ◽  
Species Specific

Sugar maple (Acer saccharum Marsh.) is a keystone species in the northern hardwood forest, and decline episodes have negatively affected the growth and health of sugar maple in portions of its range over the past 50+ years. Crown health, growth, survival, and flower and seed production of sugar maple were negatively affected by a widespread decline event in the mid-1980s on the unglaciated Allegheny Plateau in northern Pennsylvania. A long-term liming study was initiated in 1985 to evaluate responses to a one-time application of 22.4 Mg·ha–1 of dolomitic limestone in four northern hardwood stands. Over the 23-year period ending in 2008, sugar maple basal area increment (BAINC) increased significantly (P ≤ 0.05) in limed plots from 1995 through 2008, whereas American beech (Fagus grandifolia Ehrh.) BAINC was unaffected. For black cherry (Prunus serotina Ehrh.), the third principal overstory species, BAINC and survival were reduced in limed plots compared with unlimed plots. Foliar Ca and Mg remained significantly higher in sugar maple foliage sampled 21 years after lime application, showing persistence of the lime effect. These results show long-term species-specific responses to lime application.

Assessment of sugar maple health based on basal area growth pattern

2003 ◽  
Vol 33 (11) ◽  
pp. 2074-2080 ◽  
Author(s):  
Louis Duchesne ◽  
Rock Ouimet ◽  
Claude Morneau
Keyword(s):  
Growth Pattern ◽  
Acer Saccharum ◽  
Radial Growth ◽  
Sugar Maple ◽  
Basal Area ◽  
Tree Age ◽  
Tree Health ◽  
Health Decline ◽  
Area Growth ◽  
Natural Range

The first tree health decline symptoms usually observed are foliar deficiency symptoms, foliage loss, and dieback. To improve the subjective nature and unspecificity of these assessments, we examined sugar maple (Acer saccharum Marsh.) radial growth and health to develop an indicator of sugar maple tree health status based on radial growth pattern. We used the basal area increment (BAI) of 328 tree-ring collections from 16 sites located in southern Quebec, throughout the sugarbush natural range, that were categorized by defoliation class. BAI of trees with decline symptoms was significantly lower than that of healthy trees in 9 of the 16 stands. BAI trends since 1955 showed an inverse relationship with tree decline class measured in 1989, irrespective of tree age. The results indicate that declining trees in these stands have not recovered based on BAI. They also suggest that the decrease in slope of BAI predated the observed symptoms of sugar maple decline by at least one decade. Results suggest that sugar maple vigor and health can be assessed by measuring tree's BAI trend, an indicator that may be useful for the diagnosis of sugar maple health and status years before the appearance of visible canopy symptoms.

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