Development of an improved model estimating the nutrient content of the bole for four boreal tree species

1998 ◽  
Vol 28 (1) ◽  
pp. 37-43 ◽  
Author(s):  
P Rochon ◽  
D Paré ◽  
C Messier
Keyword(s):  
Populus Tremuloides ◽  
Tree Species ◽  
Picea Glauca ◽  
Nonlinear Models ◽  
Abies Balsamea ◽  
Nutrient Content ◽  
Forest Harvesting ◽  
Nutrient Concentrations ◽  
Nutrient Contents ◽  
Improved Model

An improved model for estimating nutrient contents of the commercial portion of tree boles was developed for four boreal tree species (Populus tremuloides Michx., Betula papyrifera Marsh., Picea glauca (Moench) Voss, and Abies balsamea (L.) Mill.). This model considers the spatial pattern of variation of nutrient concentrations inside the bole and its relationships with tree size. For all species-nutrient combinations, no significant pattern was found for vertical variations in nutrient concentrations, while two types of nonlinear models, using distance from the tree periphery as the independent variable, fit the pattern of horizontal (or radial) variations. These patterns of variability were used to estimate the global nutrient concentration of the bole by using mathematical integration. The values obtained with this method were generally lower, especially for large stems, than values obtained with traditional methods that do not consider the variability of nutrient concentrations inside the bole. This improved model would permit better estimates of the amounts of nutrients lost in biomass upon forest harvesting, as well as internal cycling of nutrients within the bole.

Résistance comparée de l'épinette blanche et du sapin baumier au renversement

2002 ◽  
Vol 32 (4) ◽  
pp. 642-652 ◽  
Author(s):  
S Meunier ◽  
J -C Ruel ◽  
G Laflamme ◽  
A Achim
Keyword(s):  
Tree Species ◽  
Picea Glauca ◽  
Abies Balsamea ◽  
White Spruce ◽  
Diameter Ratio ◽  
Balsam Fir ◽  
Species Vulnerability ◽  
Mesic Site ◽  
Linear Regressions ◽  
Tree Characteristics

Information on eastern Canadian tree species vulnerability to windthrow is scarce. Some statements on relative species vulnerability have been made but they rely on empirical observations, which are often difficult to generalize. In this context, a study was conducted to compare the overturning resistance of balsam fir (Abies balsamea (L.) Mill.) and white spruce (Picea glauca (Moench) Voss) on a mesic site. To establish which tree characteristics would best explain the critical turning moment, simple linear regressions were calculated using tree dendrometric data. The best regressions were obtained with stem weight. With this variable, resistance to overturning did not differ between the two species. Only regressions involving total height showed a significantly greater resistance for white spruce. This difference can be explained by a difference between the species in height–diameter relationships. For a similar height, spruce has a greater diameter, involving a higher stem weight and thus a greater resistance. Decay did not play a major role in our experiment as trees with external defects were excluded. Our results suggest that to minimize losses from windthrow, silvi cultural treatments on mesic sites should try to increase the proportion of trees of either species with the lowest height/diameter ratio.

Estimating stand-scale biomass, nutrient contents, and associated uncertainties for tree species of Canadian forests

2013 ◽  
Vol 43 (7) ◽  
pp. 599-608 ◽  
Author(s):  
David Paré ◽  
Pierre Bernier ◽  
Benoit Lafleur ◽  
Brian D. Titus ◽  
Evelyne Thiffault ◽  
...  
Keyword(s):  
Tree Species ◽  
Nutrient Concentration ◽  
Basal Area ◽  
National Database ◽  
Tree Level ◽  
Nutrient Concentrations ◽  
Bioenergy Feedstock ◽  
Concentration Data ◽  
Nutrient Contents ◽  
Biomass Equations

The growing demand for bioenergy feedstock from forest harvest residues is generating concerns about the potential loss of site productivity through nutrient removal. We used tree-level national biomass equations and a national database of forest plots to develop stand-level biomass equations for the different tree components of 30 major forest tree species found in Canada using basal area as the independent variable. We have also compiled more than 12 800 nutrient concentration values for different components of Canadian tree species from existing databases and the literature. Uncertainties were propagated across biomass equations and through conversion of nutrient concentrations to nutrient contents. Most of the uncertainty in nutrient contents estimates was found to be among the nutrient concentration measurements. The greatest levels of uncertainty were for estimates of phosphorus in woody components and of calcium in foliage. Grouping species into genera gave only a minor loss of precision. The coupling of biomass equations and nutrient concentration data can be used to provide first-order estimates of biomass and nutrients exported by tree component and species when harvesting any commercial stand in Canada. However, the associated uncertainties are important enough to warrant their inclusion in decision making.

Substrate and litterfall effects on conifer seedling survivorship in southern boreal stands of Canada

2003 ◽  
Vol 33 (4) ◽  
pp. 672-681 ◽  
Author(s):  
Marie-Josée Simard ◽  
Yves Bergeron ◽  
Luc Sirois
Keyword(s):  
Populus Tremuloides ◽  
Picea Glauca ◽  
Forest Floor ◽  
Mineral Soil ◽  
Abies Balsamea ◽  
Growing Season ◽  
Winter Survival ◽  
Thuja Occidentalis ◽  
Seedling Survivorship ◽  
Conifer Seedling

Most conifer seeds die as seeds or seedlings within 5 years after dispersal. Understanding what factors keep a few of them alive is essential if natural regeneration is to be maintained in managed forests. For example, decaying logs and the conifer seedlings that often grow on them are rare under certain canopies such as deciduous trembling aspen (Populus tremuloides Michx.). We conducted a seeding experiment to evaluate the role of certain substrates, and litterfall, on early conifer survivorship. Seeds of balsam fir (Abies balsamea (L.) Mill.), white spruce (Picea glauca (Moench) Voss), and eastern white-cedar (Thuja occidentalis L.) were sown during 2 consecutive years on mineral soil, relocated logs, and litter in deciduous aspen and coniferous (Thuja occidentalis dominated) stands. Seedling survivor ship was monitored at the end of the first growing season and 1 year after each sowing. Conifer seedling survivorship was equivalent or greater under aspen than under cedar-dominated canopies. Picea and Thuja survivorship was highest on decaying logs of approximately 9 cm high (compared with logs buried at forest floor level) and lowest on forest floor litter during both the first growing season and the following autumn–winter. Abies survivorship was little affected by substrate type, except for low autumn–winter survival on litter. Thuja autumn–winter survival was significantly reduced by litterfall in both deciduous and coniferous stands.

Partial cuts in a trembling aspen – conifer stand: effects on microenvironmental conditions and regeneration dynamics

2003 ◽  
Vol 33 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Marcel Prévost ◽  
David Pothier
Keyword(s):  
Populus Tremuloides ◽  
Picea Glauca ◽  
Abies Balsamea ◽  
Basal Area ◽  
Trembling Aspen ◽  
Limited Growth ◽  
Growth And Survival ◽  
Regeneration Dynamics ◽  
Canopy Opening ◽  
Light Soil

We present the 5-year combined effects of different cutting intensities (removal of 0, 35, 50, 65, and 100% of basal area) and scarification on available light, soil temperature, and regeneration dynamics in a mixed aspen– conifer stand in Quebec, Canada. Compared with the control, the 35% cut did not change transmitted light to the under story (<20% of full light), while the 50, 65, and 100% cuttings transmitted 30, 48, and 90% of full light, respectively, during the first summer. Trembling aspen (Populus tremuloides Michx.) suckering increased with percent basal area removal (p < 0.001). After 5 years, the 35 and 50% cuttings limited growth and survival of suckers (<1000 stems/ha, of which 5% are >1 m high), but the 65 and 100% cuttings favoured their development (8000 and 11 000 stems/ha, respectively, of which 29 and 38%, respectively, are >2 m high). Balsam fir (Abies balsamea (L.) Mill.) responded well to canopy opening alone with a maximal recruitment (31 000 seedlings/ha) in the 50% cut. Spruces (white spruce, Picea glauca (Moench) Voss, and red spruce, Picea rubens Sarg.) establish following scarification only, with a better response in the 65% cut (32 000 seedlings/ha) than in the 50 (15 000), 35 (10 000), and 0% (8000) cuttings.

Does forest tree species composition impact modelled soil recovery from acidic deposition?

2021 ◽  
Author(s):  
NEIL FJ OTT ◽  
Shaun A. Watmough
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
Soil Chemistry ◽  
Acidic Deposition ◽  
Abies Balsamea ◽  
Forest Harvesting ◽  
N Deposition ◽  
Base Saturation ◽  
Soil Base ◽  
Tree Species Composition

Acidic deposition depleted soil base cation pools throughout central Ontario, particularly during the second half of the twentieth century. While sulphur (S) and nitrogen (N) deposition have declined in recent decades, forest harvesting may continue to remove base cations from soils, highlighting the need for reliable soil chemistry forecasts. This study investigated whether differences in soil chemistry among forest stands dominated by different tree species affected predictions using a dynamic biogeochemical model (VSD). Soil base saturation was modelled from 1850–2100 in stands dominated by balsam fir (<i>Abies balsamea</i> (L.) Mill.), eastern hemlock (<i>Tsuga canadensis</i> (L.) Carr.), white pine (<i>Pinus strobus</i> L.), sugar maple (<i>Acer saccharum</i> Marsh.), or yellow birch (<i>Betula alleghaniensis</i> Britt.). Three scenarios that manipulated future atmospheric S and N deposition and forest harvesting (2020–2100) were applied. When future atmospheric S and N deposition remained at 2020 levels and harvesting continued, base saturation increased marginally (2.0–4.5%) in all plots. Further increases in base saturation were minor (~1%) by 2100 when deposition reductions were implemented. When future forest harvesting was excluded, soil base saturation increased 3.4–8.5% from 2020–2100. These results suggest that tree species composition has minimal influence on modelled soil chemistry forecasts in response to changes in acidic deposition, and such models can be broadly applied for regional predictions.

The effect of light availability and basal area on cone production in Abies balsamea and Picea glauca

2002 ◽  
Vol 80 (4) ◽  
pp. 370-377 ◽  
Author(s):  
David F Greene ◽  
Christian Messier ◽  
Hugo Asselin ◽  
Marie-Josée Fortin
Keyword(s):  
Populus Tremuloides ◽  
Picea Glauca ◽  
Light Availability ◽  
Abies Balsamea ◽  
Basal Area ◽  
White Spruce ◽  
Balsam Fir ◽  
Forest Edges ◽  
Cone Production ◽  
Effect Of Light

Mean annual seed production is assumed to be proportional to basal area for canopy trees, but it is not known if subcanopy trees produce fewer seeds than expected (given their size) because of low light availability. Ovulate cone production was examined for balsam fir (Abies balsamea (L.) Mill.) and white spruce (Picea glauca (Moench) Voss) in 1998 and for balsam fir in 2000 in western Quebec using subcanopy stems, near or far from forest edges, or (at one site) planted white spruce trees in fully open conditions. A very simple light model for transmission through mature trembling aspen (Populus tremuloides Michx.) crowns and through boles near forest edges was developed to account for the effect of light receipt on cone production. The enhanced light near forest edges (e.g., recent clearcuts) leads to about a doubling of cone production for subcanopy stems. The minimum subcanopy height for cone production far from an edge is about 10 m for balsam fir and 14 m for white spruce, with these minima decreasing near edges. By contrast, the minimum height for white spruce in a plantation (full light) is about 3 m. Accounting for light receipt leads to an increase in the explained variance.Key words: balsam fir, cone production, light model, regressions, subcanopy stems, white spruce.

Chemical transformations of deadwood and foliar litter of mixed boreal species during decomposition

2012 ◽  
Vol 42 (4) ◽  
pp. 772-788 ◽  
Author(s):  
Manuella Strukelj ◽  
Suzanne Brais ◽  
Sylvie A. Quideau ◽  
Se-Woung Oh
Keyword(s):  
Chemical Composition ◽  
Populus Tremuloides ◽  
Picea Glauca ◽  
Boreal Forests ◽  
Cupric Oxide ◽  
Abies Balsamea ◽  
Nuclear Magnetic Resonance Analysis ◽  
Chemical Transformations ◽  
Carbonyl Carbon ◽  
Important Input

Deadwood constitutes an important input of carbon to soil, but its role in carbon sequestration over the long term is not well documented in the eastern boreal forests of Canada, especially when compared with foliar litter. The objectives of this study were to characterize and compare patterns of mass loss and changes in chemical composition of deadwood and foliar litter of trembling aspen (Populus tremuloides Michx.), white spruce (Picea glauca (Moench) Voss), and balsam fir (Abies balsamea (L.) Mill.) during a 5- to 6-year period of field decomposition, using litterbags, solid-state 13C nuclear magnetic resonance analysis, and lignin monomer quantification by cupric oxide oxidation. The maximum decomposition limit was similar between foliar litter and wood material, but foliar litter decomposed faster, reached the estimated maximum decomposition limit, and converged to a composition rich in alkyl, phenolic, and carbonyl carbon. However, wood did not reach the estimated maximum decomposition limit and underwent relatively little chemical changes, remaining with high carbohydrate content. At the end of the experiment, aspen wood still had a lower lignin concentration than that of conifers, but contained higher proportions of alkyl and carbonyl carbon. Although wood contributes to a greater diversity in the chemical composition of the forest floor, foliar litter, which keeps a high alkyl C content throughout its decay, could generate more recalcitrant residual organic matter.

scholarly journals Semi-natural and intensive silvicultural systems for the boreal mixedwood forest

1996 ◽  
Vol 72 (3) ◽  
pp. 286-292 ◽  
Author(s):  
V. J. Lieffers ◽  
J. D. Stewart ◽  
R. B. Macmillan ◽  
D. Macpherson ◽  
K. Branter
Keyword(s):  
Populus Tremuloides ◽  
Land Tenure ◽  
Picea Glauca ◽  
Abies Balsamea ◽  
White Spruce ◽  
Growth And Yield ◽  
Mixedwood Forests ◽  
Seed Sources ◽  
Starting Point ◽  
Western Boreal Forest

Boreal mixedwood forests of aspen (Populus tremuloides) and white spruce (Picea glauca) are found on mesic sites in the western boreal forest. In the natural development of mixedwood stands, aspen is usually the first species to dominate the site. However, depending upon spruce seed sources and seedbeds, spruce can establish immediately after disturbance or in the next several decades. In most cases, spruce grow in the understory of deciduous species during its early development. If there are no spruce seed sources, aspen may be the sole tree species for a long period. In most circumstances, however, the longer-lived and taller white spruce eventually becomes the dominant species. If stands remain undisturbed for long periods, they will likely become uneven-aged mixtures of spruce and balsam fir (Abies balsamea). We propose silvicultural systems that will develop stands of a range of compositions, structures and value. As a starting point, we identify eight different mixed-wood compositions that might be identified in stand inventories, and propose various silvicultural treatments, including underplanting of white spruce, understory protection, shelterwood, and uneven-aged management. Fundamental changes in land tenure and silvicultural regulations, and improvements in estimation of growth and yield will be required before this range of management of mixed-woods can be implemented. Key words: aspen, white spruce, shelterwood, Populus tremuloides, Picea glauca, succession, ecosystem management

Litterfall and litter nutrient content in primary and secondary Amazonian ‘terra firme’ rain forest

1989 ◽  
Vol 5 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Mario Dantas ◽  
John Phillipson
Keyword(s):  
Primary Production ◽  
Secondary Forest ◽  
Net Primary Production ◽  
Nutrient Content ◽  
Nutrient Concentrations ◽  
Primary Forest ◽  
Forest Site ◽  
Secondary Forests ◽  
Forest Types ◽  
Nutrient Contents

ABSTRACTLitterfall in primary and secondary forests (‘capoeira’) in eastern Brazilian Amazonia was measured fortnightly from August 1979 to October 1980. The nutrient contents of the litter (N, P, K, Ca and Mg) were determined.Litterfall differed between the two forest types (primary forest − 8.04 t ha−1 yr−1; secondary forest − 5.04 t ha−1 yr−1). The value obtained for primary forest was similar to those reported elsewhere in Brazil (mean = 8 t ha−1 yr−1) and from other regions of S. America (mean = 7.20 t ha−1 yr−1).Prediction of net primary production from litterfall at the primary forest site gave rise to values of 14.47 and 26.53 t ha−1 yr−1. Estimates of net primary production in ‘capoeira’ ranged from 9.07 to 16.63 t ha−1 yr−1.Seasonality of litterfall was more marked in ‘capoeira’ than primary forest but in both cases was less pronounced than elsewhere in Brazil.Nutrient concentrations were highest in ‘capoeira’ litter, a finding which accords with results from other tropical sites; nevertheless input of nutrients per unit area of forest floor was greatest in the primary forest.

Insects can limit seed productivity at the treeline

2015 ◽  
Vol 45 (3) ◽  
pp. 286-296 ◽  
Author(s):  
Ryan G. Jameson ◽  
Andrew J. Trant ◽  
Luise Hermanutz
Keyword(s):  
Seed Germination ◽  
Seed Production ◽  
Seed Predation ◽  
Tree Species ◽  
Picea Glauca ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Insect Larvae ◽  
Seed Productivity ◽  
Change Models

Numerous factors contribute to the variability in treeline change; however, the potential role of insect predation in limiting seed productivity is not well documented. Conditions for seed germination, establishment, and survival are not limiting at the Mealy Mountains treeline (Labrador, Canada), but seedlings are rarely encountered, suggesting a seed-related bottleneck to recruitment. Mature cones were collected in 2008 from four tree species (black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.), balsam fir (Abies balsamea (L.) Mill.), eastern larch (Larix laricina (Du Roi) K. Koch), and white spruce (Picea glauca (Moench) Voss)) across three treeline zones (forest, transition, and krummholz) to assess potential seed limitation. During that year, an unexpectedly high diversity of insect larvae caused extensive reproductive loss and damaged the cones of ∼85% of trees sampled, confirming that treeline change models should include seed predation. Seed germination was low and variable in all treeline zones, although significantly higher in black spruce and eastern larch. Most reproductive quality measures decreased significantly with elevation, although no differences among zones or tree species in the percentages of seeds damaged by insects were found (mean ± standard deviation: 31% ± 23%). Based on tree density and seed production, black spruce is predicted to lead the treeline expansion in the Mealy Mountains. Although climate warming may create conditions conducive for increased seed production, predispersal seed predation may limit future treeline expansion.

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