Dynamics of the boreal forest south of James Bay

1978 ◽  
Vol 56 (9) ◽  
pp. 1157-1173 ◽  
Author(s):  
T. J. Carleton ◽  
P. F. Maycock
Keyword(s):  
Boreal Forest ◽  
Tree Species ◽  
Forest Succession ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Primary Forest ◽  
General Notion ◽  
Forest Stands ◽  
James Bay ◽  
Forest Zone

Ordination models of approximate environmental and dynamic relationship between eight boreal tree species were constructed based upon principal components analysis and Kruskal's nonmetric multidimensional scaling. The assumptions inherent in these models are stated and discussed. The data consisted of 152 forest stands from the closed-crown boreal forest zone of Ontario and Quebec south of James Bay. Sequential forest succession, as demonstrated by similar techniques for a section of the Wisconsin evergreen–hardwood forest, is not common in the region of boreal forest studied. However, for those species in common between this and the Wisconsin study, similar dynamic pathways are indicated despite differences in sample size and field technique. Tree species developmental pathways, as indicated by 'succession vectors' on the ordination models are, for the most part, short and circular with the exception of Abies balsamea (balsam fir). This reflects the reestablishment of similar, relatively monospecific forest stands following catastrophic forest destruction by fire and (or) other agencies. Where catastrophe does not intervene, deciduous primary forest species may be succeeded by an understory of A. balsamea or by Picea mariana (black spruce). Equally, some forest stands of primary establishment may become decadent with little or no subsequent tree growth. These observations are discussed with respect to the general notion of forest succession.

Fire return intervals and tree species succession in the North Shore region of eastern Quebec

2008 ◽  
Vol 38 (6) ◽  
pp. 1621-1633 ◽  
Author(s):  
Mathieu Bouchard ◽  
David Pothier ◽  
Sylvie Gauthier
Keyword(s):  
Tree Species ◽  
Forest Succession ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Balsam Fir ◽  
Geographic Variations ◽  
Forest Patches ◽  
The North ◽  
Species Succession ◽  
South Axis

We evaluated geographic variations in mean fire return intervals and postfire forest succession within a 66 497 km2 land area located in the eastern Quebec boreal forest. Fire return intervals were calculated using a time since last fire map for 1800–2000, and forest dynamics were studied by superimposing 3204 forest inventory plots onto the fire map. Mean fire return interval proved significantly shorter in the western part of the study area, at 270 years, compared with the eastern part, where it was probably more than 500 years. The two main tree species in the study area were balsam fir ( Abies balsamea (L.) P. Mill.) and black spruce ( Picea mariana (Mill.) BSP). Balsam fir abundance increased progressively as a function of time since fire, whereas black spruce abundance increased during the first 90 years after fire and then declined. Balsam fir was significantly more abundant in the southeastern portion of the study area, which we attribute to the combined limitations imposed by temperature along the north–south axis and by fire along the east–west axis. Large forest patches (i.e., ≥200 km2) dominated by early successional tree species, within a matrix of irregular black spruce – balsam fir mixtures, are an important feature of preindustrial forest landscapes in this region.

Understorey–canopy affinities in boreal forest vegetation

1981 ◽  
Vol 59 (9) ◽  
pp. 1709-1716 ◽  
Author(s):  
T. J. Carleton ◽  
P. F. Maycock
Keyword(s):  
Boreal Forest ◽  
Relative Density ◽  
Forest Fire ◽  
Tree Species ◽  
Nutrient Status ◽  
James Bay ◽  
Apparent Lack ◽  
Stem Size ◽  
Single Tree ◽  
Natural Combination

One hundred and ninety-seven boreal forest stands, in a region of Ontario and Quebec south of James Bay, were examined. Tree species were summarized as relative density of each of five stem size classes. These data formed the basis for an exclusive polythetic divisive stand classification into 10 groups. Most of these groups were characterized by a single tree species. The affinity of each of 410 understorey taxa was assessed with respect to each canopy stand group or natural combination of groups. Only 121 understorey taxa showed specificity to the canopy classes identified. This apparent lack of tight overstorey–understorey affinity is discussed in relation to site nutrient status and regeneration following forest fire.

Relative importance of different secondary successional pathways in an Alaskan boreal forest

2008 ◽  
Vol 38 (7) ◽  
pp. 1911-1923 ◽  
Author(s):  
Thomas A. Kurkowski ◽  
Daniel H. Mann ◽  
T. Scott Rupp ◽  
David L. Verbyla
Keyword(s):  
Boreal Forest ◽  
Tree Species ◽  
Black Spruce ◽  
Fire Frequency ◽  
Forest Composition ◽  
Stand Age ◽  
Solar Insolation ◽  
Species Dominance ◽  
Complex Landscape ◽  
Successional Pathways

Postfire succession in the Alaskan boreal forest follows several different pathways, the most common being self-replacement and species-dominance relay. In self-replacement, canopy-dominant tree species replace themselves as the postfire dominants. It implies a relatively unchanging forest composition through time maintained by trees segregated within their respective, ecophysiological niches on an environmentally complex landscape. In contrast, species-dominance relay involves the simultaneous, postfire establishment of multiple tree species, followed by later shifts in canopy dominance. It implies that stand compositions vary with time since last fire. The relative frequencies of these and other successional pathways are poorly understood, despite their importance in determining the species mosaic of the present forest and their varying, potential responses to climate changes. Here we assess the relative frequencies of different successional pathways by modeling the relationship between stand type, solar insolation, and altitude; by describing how stand age relates to species composition; and by inferring successional trajectories from stand understories. Results suggest that >70% of the study forest is the product of self-replacement, and tree distributions are controlled mainly by the spatial distribution of solar insolation and altitude, not by time since last fire. As climate warms over the coming decades, deciduous trees will invade cold sites formerly dominated by black spruce, and increased fire frequency will make species-dominance relay even rarer.

Long-term impact of fire on high-altitude balsam fir (Abies balsamea) forests in south-central Quebec deduced from soil charcoal

2013 ◽  
Vol 43 (2) ◽  
pp. 188-199 ◽  
Author(s):  
Pierre-Luc Couillard ◽  
Serge Payette ◽  
Pierre Grondin
Keyword(s):  
Boreal Forest ◽  
High Altitude ◽  
Tree Species ◽  
Abies Balsamea ◽  
Balsam Fir ◽  
Forest Landscape ◽  
White Birch ◽  
Soil Charcoal ◽  
Fire Activity

Extensive balsam fir (Abies balsamea (L.) Mill.) stands across the southern boreal forest are ecosystems likely more influenced by insect outbreaks and windthrows than by fire. To what degree the dominance of balsam fir stands reflects past and present disturbance dynamics associated with fire is not well documented. To answer this question, we focused on the reconstruction of the long-term fire history of high-altitude balsam fir forests of southern Quebec. The reconstruction was based on botanically identified and radiocarbon-dated soil charcoal particles in 19 sites covering successional stages from white birch (Betula payrifera Marsh.) to mixed white birch – balsam fir stands. Fire activity commenced early after deglaciation, about 9600 calibrated years before present when the first boreal tree species were established. Fire occurred recurrently during the following 5000 years with a forest landscape composed of the principal tree species common to the boreal forest, including jack pine (Pinus banksiana Lamb.). Fire activity ceased more or less abruptly about 4500 years ago due to less fire-conducive, more humid conditions. Then, the forest landscape progressively changed towards a larger representation of white birch – balsam fir forests and the disappearance of jack pine. Whereas several balsam fir stands have not burned over the last 4500 years, scattered fires occurred in particular over the last 250 years when 1815 and 1878 fires, probably man-made, burned 50% of the forest, thus causing a major change in the composition of the forest landscape. It is concluded that the high-altitude forest landscape of southern Quebec changed profoundly over the Holocene in close association with a time-transgressive dry-to-wet climatic gradient.

scholarly journals Boreal tree regeneration after fire and fuelwood harvesting in coastal Nunatsiavut

2020 ◽  
Vol 6 (4) ◽  
pp. 384-403
Author(s):  
Lucas Brehaut ◽  
Carissa D. Brown
Keyword(s):  
Boreal Forest ◽  
Forest Regeneration ◽  
Abies Balsamea ◽  
Tree Regeneration ◽  
Tree Age ◽  
Published Data ◽  
Stem Density ◽  
Forest Stands ◽  
Seedling Regeneration ◽  
The People

Consecutive landscape-scale disturbances are known to influence boreal forest regeneration, yet few published data exist on the compounding effects of natural and anthropogenic disturbance on regeneration in subarctic forests. We conducted a dendroecological study of eastern coastal boreal forest regeneration two decades after fire at three subarctic forest stands that are important sources of fuelwood for the people of Nunatsiavut (Labrador, Canada). We quantified spruce (Picea spp.) and balsam fir (Abies balsamea (L.) Mill.) seedling regeneration, standing dead tree density, trees harvested within burned forests, and aged proximal unburned stands. Age of unburned forest varied with site; however, each exhibited continuous regeneration over several decades. Despite low seedling regeneration at each site (stems·m−2; less than 35% of pre-fire stem density), model results indicated harvesting post-fire did not impact seedling regeneration. Findings suggest a negative pressure on seedling abundance from increased presence of tall multi-stemmed shrubs, yet we argue that because stands exhibit a range in tree age, shrubs may be a set of early successional species rather than indicating a change in successional trajectory. Examination of a larger chronosequence within coastal forest stands of Nunatsiavut is warranted to further understand forest regeneration in the eastern subarctic under changing disturbance regimes.

Clearcutting — a regeneration method in the boreal forest

1996 ◽  
Vol 72 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Andrew Youngblood ◽  
Brian Titus
Keyword(s):  
North America ◽  
Boreal Forest ◽  
Key Words ◽  
Tree Species ◽  
Forest Regeneration ◽  
Forest Ecosystems ◽  
New Age ◽  
Forest Stands ◽  
Age Class ◽  
Ecological Basis

Clearcutting is a method of regenerating an even-aged stand in which a new age class develops in a fully exposed microclimate after a single cutting of all trees in the previous stand. It is a common regeneration method used throughout the boreal forest of North America. The ecological basis for reliance on this method of regenerating forest stands is examined, including considerations for specific tree species, for stands, and increasingly more important, for forest ecosystems. Despite past success and continued reliance on this method of regeneration in the boreal forest, alternative regeneration methods are proving to be equally feasible. Key words: clearcutting, forest regeneration, boreal forest

Structure, composition, and diversity of old-growth black spruce boreal forest of the Clay Belt region in Quebec and Ontario

2003 ◽  
Vol 11 (S1) ◽  
pp. S79-S98 ◽  
Author(s):  
Karen Harper ◽  
Catherine Boudreault ◽  
Louis DeGrandpré ◽  
Pierre Drapeau ◽  
Sylvie Gauthier ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Picea Mariana ◽  
Black Spruce ◽  
Small Scale ◽  
Structural Development ◽  
Spruce Forest ◽  
Forest Stands ◽  
Old Growth ◽  
Old Growth Forest ◽  
Old Growth Forests

Old-growth black spruce (Picea mariana) boreal forest in the Clay Belt region of Ontario and Quebec is an open forest with a low canopy, quite different from what many consider to be "old growth". Here, we provide an overview of the characteristics of old-growth black spruce forest for three different site types on organic, clay, and coarse deposits. Our objectives were (1) to identify the extent of older forests; (2) to describe the structure, composition, and diversity in different age classes; and (3) to identify key processes in old-growth black spruce forest. We sampled canopy composition, deadwood abundance, understorey composition, and nonvascular plant species in 91 forest stands along a chronosequence that extended from 20 to more than 250 years after fire. We used a peak in tree basal area, which occurred at 100 years on clay and coarse sites and at 200 years on organic sites, as a process-based means of defining the start of old-growth forest. Old-growth forests are extensive in the Clay Belt, covering 30–50% of the forested landscape. Black spruce was dominant on all organic sites, and in all older stands. Although there were fewer understorey species and none exclusive to old-growth, these forests were structurally diverse and had greater abundance of Sphagnum, epiphytic lichens, and ericaceous species. Paludification, a process characteristic of old-growth forest stands on clay deposits in this region, causes decreases in tree and deadwood abundance. Old-growth black spruce forests, therefore, lack the large trees and snags that are characteristic of other old-growth forests. Small-scale disturbances such as spruce budworm and windthrow are common, creating numerous gaps. Landscape and stand level management strategies could minimize structural changes caused by harvesting, but unmanaged forest in all stages of development must be preserved in order to conserve all the attributes of old-growth black spruce forest. Key words: boreal forest, old growth, paludification, Picea mariana, structural development, succession.

Forest dynamics following spruce budworm outbreaks in the northern and southern mixedwoods of central Quebec

2007 ◽  
Vol 37 (4) ◽  
pp. 763-772 ◽  
Author(s):  
Mathieu Bouchard ◽  
Daniel Kneeshaw ◽  
Christian Messier
Keyword(s):  
Forest Dynamics ◽  
Forest Succession ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Northern Region ◽  
Southern Region ◽  
Aerial Photographs ◽  
Forest Zone ◽  
Hardwood Species

The effects of 20th century spruce budworm ( Choristoneura fumiferana (Clem.)) outbreaks on forest dynamics was examined in the southern and northern parts of the mixedwood forest zone in central Quebec, Canada. In each region, three study areas were placed in unmanaged stands that had not burned for more than 200 years. Disturbance impacts and forest succession were evaluated using aerial photographs and dendrochronology. Spruce budworm outbreaks occurred around 1910, 1950, and 1980 in both regions. The 1910 outbreak seemed to have limited impact in both regions, and the 1950 outbreak caused heavy mortality in conifer stands (mostly of balsam fir, Abies balsamea (L.) Mill.) in the southern region. The 1980 outbreak caused major mortality in the northern region, but had little impact in the southern region. Successive spruce budworm outbreaks led to a massive invasion by hardwood species in the last century in the southern region but not in the northern region. The reason for such contrasting dynamics between regions is unknown, but we hypothesize that differences in disturbance intensities, influenced by climate, played a major role. Results from this study emphasize that generalizations about the effect of spruce budworm outbreaks on forest dynamics cannot be derived from observations made during a single outbreak or at a single location.

Distribution and dynamics of tree species across a fire frequency gradient in the James Bay region of Quebec

2003 ◽  
Vol 33 (2) ◽  
pp. 243-256 ◽  
Author(s):  
Marc-André Parisien ◽  
Luc Sirois
Keyword(s):  
Tree Species ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Black Spruce ◽  
Species Abundance ◽  
White Spruce ◽  
Fire Frequency ◽  
Jack Pine ◽  
James Bay ◽  
Fire Cycle

This study examines how forest structure and composition change with spatial variations in the fire cycle across a shore-hinterland gradient. Twenty-one well-drained sites were sampled at different distances from James Bay to describe the forest stands. To quantify the role of fire in tree species distribution, a spatial analysis of fire polygons from 1930 to 1998 was undertaken in a 43 228 km2 study area adjacent to James Bay. Results from this analysis reveal an important decrease in the fire cycle, from 3142 to 115 years, from the shore to the hinterland. In forests bordering James Bay, white spruce (Picea glauca (Moench) Voss) is found in pure stands. It is gradually replaced by black spruce (Picea mariana (Mill.) BSP) at 0.5 km from the shore. Jack pine (Pinus banksiana Lamb.) abruptly appears at 22 km from the shore. There is a positive correlation between the frequency of white spruce and the fire cycle (R = 0.893), whereas this correlation is negative for black spruce (R = –0.753) and jack pine (R = –0.807) (Spearman correlations). Jack pine is confined to regions having a short fire cycle, while black spruce can seemingly maintain itself with or without fire. The exclusion of white spruce hinterland seems to be mainly due to a short fire cycle; however, other factors, such as soil development and species abundance, presumably have a marked influence on the distribution of this species.

Effects of mechanized careful logging on natural regeneration and vegetation competition in the southeastern Canadian boreal forest

2002 ◽  
Vol 32 (4) ◽  
pp. 653-666 ◽  
Author(s):  
Brian Harvey ◽  
Suzanne Brais
Keyword(s):  
Boreal Forest ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Rubus Idaeus ◽  
Larix Laricina ◽  
Silty Clay ◽  
Predominantly Black ◽  
Vegetation Development ◽  
Monitoring Study ◽  
Canadian Boreal Forest

Careful logging regulations in Quebec restrict circulation of harvesting and forwarding or skidding machinery to evenly spaced, parallel trails, which creates a particular pattern of disturbed and relatively undisturbed zones in cutovers. A 7-year monitoring study was established to evaluate the effects of careful logging on vegetation development in the southern boreal forest of Quebec. A total of 255 sample plots (2 m2) were located in seven cutovers in predominantly black spruce (Picea mariana (Mill.) BSP) forests that were whole-tree "careful logged": 120 on fresh to moist silty clays or silty clay loams and 135 on dry to fresh loamy sands. Three microsites were sampled: skid trails and the edge and the centre of protection strips. A gradient of disturbance from the skid trail to centre of the protection strip was evident for finer textured sites. Careful logging resulted in high densities of black spruce and balsam fir (Abies balsamea (L.) Mill.) (> 20 000 stems/ha each) in the protection strip. Survival of other understory species was also favoured in protection strips. Higher disturbance levels in skid trails favoured establishment of larch (Larix laricina (Du Roi) K. Koch), raspberry (Rubus idaeus L.), and graminoids. Reduction of ericaceous cover occurred in skid trails on coarse-textured sites but was only temporary. Softwood stocking 7 years after harvest (based on 2-m2 plots), ranged from 69 to 74% on fine- to medium-textured sites and from 31 to 51% on coarse-textured sites. The pattern of vegetation development created by careful logging has important implications for silvicultural decisions and stand modelling.

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