Gap dynamics and replacement patterns in gaps of the northeastern boreal forest of Quebec

2004 ◽  
Vol 34 (2) ◽  
pp. 353-364 ◽  
Author(s):  
Anh Thu Pham ◽  
Louis De Grandpré ◽  
Sylvie Gauthier ◽  
Yves Bergeron
Keyword(s):  
Boreal Forest ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Small Scale ◽  
Natural Mortality ◽  
Gap Dynamics ◽  
Structural Components ◽  
Species Replacement ◽  
Insect Outbreaks ◽  
Humid Climate

The northeastern boreal forest of Quebec is characterized by a humid climate. Consequently, fires are less frequent and small-scale disturbances play an important role in forest dynamics. Natural mortality and nonfire disturbances such as insect outbreaks and windthrow lead to gap-driven processes. Changes in structure and species composition can result from gap dynamics. The objectives of this study were to characterize gaps and examine patterns of species replacement in gaps in old conifer stands. Line intersect sampling was used to sample stands dominated by balsam fir (Abies balsamea (L.) Mill.) and (or) black spruce (Picea mariana (Mill.) BSP). Results show that 54% of the forest was in expanded gaps and that canopy gaps are relatively small, since 87% of them were smaller than 100 m2. The majority (94%) of the openings were caused by the mortality of less than 10 gap makers. Replacement probabilities show self-replacement of A. balsamea in Abies stands and of P. mariana in Picea stands. However, in Abies-Picea stands, there seems to be a reciprocal replacement of the two species. These results provide knowledge of the disturbance dynamics of the region as a basis for development of silvicultural practices that preserve the structural components of older forest stands.

Effects of local changes in active layer and soil climate on seasonal foliar nitrogen concentrations of three boreal forest shrubs

2007 ◽  
Vol 37 (2) ◽  
pp. 383-394 ◽  
Author(s):  
Jennifer K. Rohrs-Richey ◽  
Christa P.H. Mulder
Keyword(s):  
Boreal Forest ◽  
Active Layer ◽  
Black Spruce ◽  
Growth Strategy ◽  
Small Scale ◽  
Regional Warming ◽  
Vaccinium Uliginosum ◽  
Foliar N ◽  
Nitrogen Concentrations ◽  
Soil Climate

Caribou Poker Creeks Research Watershed is a boreal forest watershed in Interior Alaska that is susceptible to regional warming and permafrost thaw. We measured seasonal foliar N concentrations of the black spruce understory shrubs, Vaccinium uliginosum L., Vaccinium vitis-idaea L., and Ledum palustre L. on north- and south-facing sides of the watershed. We predicted that the shrubs would respond to small-scale changes in active layer and soil climate, and we expected similar responses according to growth strategy (evergreen or deciduous). Overall, foliar N in shrubs was higher on warmer, drier soils with deep active layers: +7.9% N in V. uliginosum, +11.1% N in V. vitis-idaea, and +9.4% N in L. palustre. Each shrub had species-specific foliar N patterns that could not be categorized by growth strategy and were not well explained by soil climate or active layer. Leaf mineral nutrition is influenced by multiple processes, and foliar N was best explained by the combination of environmental variables operating at the study site. For Caribou Poker Creeks Research Watershed, we can expect increased N status of the black spruce understory along with continued climate warming, but changes cannot be predicted based on growth strategy.

scholarly journals Root-Associated Ectomycorrhizal Fungi Shared by Various Boreal Forest Seedlings Naturally Regenerating after a Fire in Interior Alaska and Correlation of Different Fungi with Host Growth Responses

2011 ◽  
Vol 77 (10) ◽  
pp. 3351-3359 ◽  
Author(s):  
Elizabeth Bent ◽  
Preston Kiekel ◽  
Rebecca Brenton ◽  
D. Lee Taylor
Keyword(s):  
Boreal Forest ◽  
Populus Tremuloides ◽  
Fungal Community ◽  
Black Spruce ◽  
Molecular Techniques ◽  
Root Tip ◽  
Small Scale ◽  
Growth Responses ◽  
Root Tips ◽  
Content Type

ABSTRACTThe role of common mycorrhizal networks (CMNs) in postfire boreal forest successional trajectories is unknown. We investigated this issue by sampling a 50-m by 40-m area of naturally regenerating black spruce (Picea mariana), trembling aspen (Populus tremuloides), and paper birch (Betula papyrifera) seedlings at various distances from alder (Alnus viridissubsp.crispa), a nitrogen-fixing shrub, 5 years after wildfire in an Alaskan interior boreal forest. Shoot biomasses and stem diameters of 4-year-old seedlings were recorded, and the fungal community associated with ectomycorrhizal (ECM) root tips from each seedling was profiled using molecular techniques. We found distinct assemblages of fungi associated with alder compared with those associated with the other tree species, making the formation of CMNs between them unlikely. However, among the spruce, aspen, and birch seedlings, there were many shared fungi (including members of thePezoloma ericae[Hymenoscyphus ericae] species aggregate,Thelephora terrestris, andRussulaspp.), raising the possibility that these regenerating seedlings may form interspecies CMNs. Distance between samples did not influence how similar ECM root tip-associated fungal communities were, and of the fungal groups identified, only one of them was more likely to be shared between seedlings that were closer together, suggesting that the majority of fungi surveyed did not have a clumped distribution across the small scale of this study. The presence of some fungal ribotypes was associated with larger or smaller seedlings, suggesting that these fungi may play a role in the promotion or inhibition of seedling growth. The fungal ribotypes associated with larger seedlings were different between spruce, aspen, and birch, suggesting differential impacts of some host-fungus combinations. One may speculate that wildfire-induced shifts in a given soil fungal community could result in variation in the growth response of different plant species after fire and a shift in regenerating vegetation.

scholarly journals Vulnerability of Conifer Regeneration to Spruce Budworm Outbreaks in the Eastern Canadian Boreal Forest

Forests ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 850 ◽  
Author(s):  
Janie Lavoie ◽  
Miguel Montoro Girona ◽  
Hubert Morin
Keyword(s):  
Boreal Forests ◽  
Black Spruce ◽  
Choristoneura Fumiferana ◽  
Management Strategies ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Insect Outbreaks ◽  
Spruce Stands ◽  
Canadian Boreal Forest

Spruce budworm (Choristoneura fumiferana) is the main defoliator of conifer trees in North American boreal forests, affecting extensive areas and causing marked losses of timber supplies. In 2017, spruce budworm affected more than 7 million ha of Eastern Canadian forest. Defoliation was particularly severe for black spruce (Picea mariana (Mill.) B.S.P.), one of the most important commercial trees in Canada. During the last decades, intensive forest exploitation practices have created vast stands of young balsam fir (Abies balsamea (L.) Mill.) and black spruce. Most research focused on the impacts of spruce budworm has been on mature stands; its effects on regeneration, however, have been neglected. This study evaluates the impacts of spruce budworm on the defoliation of conifer seedlings (black spruce and balsam fir) in clearcuts. We measured the cumulative and annual defoliation of seedlings within six clearcut black spruce stands in Quebec (Canada) that had experienced severe levels of defoliation due to spruce budworm. For all sampled seedlings, we recorded tree species, height class, and distance to the residual forest. Seedling height and species strongly influenced defoliation level. Small seedlings were less affected by spruce budworm activity. As well, cumulative defoliation for balsam fir was double that of black spruce (21% and 9%, respectively). Distance to residual stands had no significant effect on seedling defoliation. As insect outbreaks in boreal forests are expected to become more severe and frequent in the near future, our results are important for adapting forest management strategies to insect outbreaks in a context of climate change.

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.

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.

Spatiotemporal evolution of paludification associated with autogenic and allogenic factors in the black spruce–moss boreal forest of Québec, Canada

2019 ◽  
Vol 91 (2) ◽  
pp. 650-664 ◽  
Author(s):  
Éloïse Le Stum-Boivin ◽  
Gabriel Magnan ◽  
Michelle Garneau ◽  
Nicole J. Fenton ◽  
Pierre Grondin ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Vegetation Dynamics ◽  
Pinus Banksiana ◽  
Fire History ◽  
Black Spruce ◽  
Mineral Soil ◽  
Abies Balsamea ◽  
Organic Layer ◽  
Coniferous Species ◽  
Topographic Depressions

AbstractPaludification is the most common process of peatland formation in boreal regions. In this study, we investigated the autogenic (e.g., topography) and allogenic (fire and climate) factors triggering paludification in different geomorphological contexts (glaciolacustrine silty-clayey and fluvioglacial deposits) within the Québec black spruce (Picea mariana)–moss boreal forest. Paleoecological analyses were conducted along three toposequences varying from a forest on mineral soil to forested and semi-open peatlands. Plant macrofossil and charcoal analyses were performed on basal peat sections (≤50 cm) and thick forest humus (<40 cm) to reconstruct local vegetation dynamics and fire history involved in the paludification process. Results show that primary paludification started in small topographic depressions after land emergence ca. 8000 cal yr BP within rich fens. Lateral peatland expansion and secondary paludification into adjacent forests occurred between ca. 5100 and 2300 cal yr BP and resulted from low-severity fires during a climatic deterioration. Fires that reduced or eliminated entirely the organic layer promoted the establishment ofSphagnumin microdepressions. Paludification resulted in the decline of some coniferous species such asAbies balsameaandPinus banksiana. The paleoecological approach along toposequences allowed us to understand the spatiotemporal dynamics of paludification and its impacts on the vegetation dynamics over the Holocene.

Linking stand attributes to cartographic information for ecosystem management purposes in the boreal forest of eastern Québec

2010 ◽  
Vol 86 (4) ◽  
pp. 511-519 ◽  
Author(s):  
Guillaume Côté ◽  
Mathieu Bouchard ◽  
David Pothier ◽  
Sylvie Gauthier
Keyword(s):  
Boreal Forest ◽  
Ecosystem Management ◽  
Large Scale ◽  
Stand Structure ◽  
Black Spruce ◽  
Management Strategies ◽  
Abies Balsamea ◽  
Forest Types ◽  
Forest Classification ◽  
Stand Characteristics

In the North American boreal forest, the adoption of forest ecosystem management strategies usually increases the number of forest stands to be treated with irregular or uneven-aged silvicultural systems. However, it is difficult to properly target the stands most appropriate for partial cut treatments in remote areas where road access is limited, because current inventory data do not include an assessment of key stand characteristics for silvicultural prescriptions, such as the abundance of small stems in the understory. In this study, we present a forest classification performed using classification and ordination methods, based on ground-measured structural and compositional stand characteristics, in a region of eastern Québec, Canada. This classification resulted in six forest types, which range in composition and structure from relatively regular post-fire stands dominated by black spruce (Picea mariana) to relatively irregular stands co-dominated by balsam fir (Abies balsamea) and black spruce. This classification was linked with cartographic information currently available to forest managers. Information from a fine-scale forest map predicted slightly better the presence of forest types with irregular stand structures compared with a coarse-scale forest map complemented with a fire map. Thus, areas most suitable for the implementation of uneven-aged silvicultural systems can be roughly delineated from existing cartographic information, which will facilitate their integration into large-scale and long-term forest management plans.Key words: boreal forest, forest classification, forest dynamics, stand structure, silviculture

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 frequency and vegetation dynamics for the south-central boreal forest of Quebec, Canada

2002 ◽  
Vol 32 (11) ◽  
pp. 1996-2009 ◽  
Author(s):  
Daniel Lesieur ◽  
Sylvie Gauthier ◽  
Yves Bergeron
Keyword(s):  
Forest Management ◽  
Boreal Forest ◽  
Forest Dynamics ◽  
Little Ice Age ◽  
Black Spruce ◽  
Fire Frequency ◽  
Ice Age ◽  
Species Replacement ◽  
Fire Cycle ◽  
South Central

Fire history and forest dynamics were reconstructed for a 3800-km2 territory located in the south-central boreal forest of Quebec. Fire cycle was characterized using a random sampling strategy combined with archival data on fires that had occurred since 1923 on private land owned by Smurfit-Stone. Bioclimatic subdomain, land use, surficial deposit, and mean distance from a firebreak did not affect the fire cycle. Fire cycles have been longer since the end of the Little Ice Age (~1850). Warming after the Little Ice Age seems to have triggered a change in fire frequency. Forest dynamics were characterized by transition matrices for changes in dominant canopy composition from 344 permanent sampling plots. These permanent plots were sampled approximately every 15 years over the preceding 40 years. We observed two distinct patterns of replacement: (i) deciduous and mixed stands were replaced by balsam fir (Abies balsamifera (L.) Mill.) (and, to a lesser extent, by black spruce (Picea mariana (Mill.) BSP)) and (ii) jack pine (Pinus banksiana Lamb.) was replaced by black spruce. Analyses confirm that species replacement occurs in the eastern boreal forest of Canada when the fire-return interval is long enough and that the substrate plays an important role along with other disturbances, such as insect outbreaks. Our results also suggest that the proportion of old-growth forests (>100 years old) in the landscape should increase as a result of the lengthening of the fire cycle. More and more stands are likely to experience species replacement. From the standpoint of sustainable forest management, this perspective calls into question the widespread use of clear-cutting in the boreal forest. Regional context must be taken into account in forest management if the conservation of biodiversity and ecosystem integrity are serious objectives. Economically and ecologically sound silvicultural scenarios that emulate natural processes are discussed.

Temporal changes in stem decay and dead and sound wood volumes in the northeastern Canadian boreal forest

2013 ◽  
Vol 43 (3) ◽  
pp. 234-244 ◽  
Author(s):  
Julie Barrette ◽  
David Pothier ◽  
Charles Ward
Keyword(s):  
Boreal Forest ◽  
Picea Mariana ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Forest Stand ◽  
Old Growth ◽  
Wood Volume ◽  
Dead Trees ◽  
Positive Balance ◽  
Canadian Boreal Forest

Yield tables used for stand-level predictions of standing volume typically do not account for the presence of dead trees and stem decay. Yet, recently dead trees, referred to as dead and sound wood (DSW), could be considered as a valuable supplemental wood source. Conversely, stem decay can cause important losses during product recovery. Accordingly, the general objective of this study was to characterize the patterns of change of stem decay and of DSW as functions of time since the last fire (TSF). The amount of stem decay and of DSW per tree species were measured in two chronosequences of 30 stands each, covering more than 1000 years in the northeastern Canadian boreal forest. Stand-level decay volume increased during the first 150 years following fire and then stabilized. This volume was mainly composed of black spruce (Picea mariana (Mill.) BSP) when TSF <200 years and of balsam fir (Abies balsamea (L.) Mill.) when TSF >200 years. Conversely, the volume of DSW declined rapidly after fire and increased gradually from about 200 years TSF. Hence, the loss of wood volume attributable to stem decay in old-growth stands was cancelled out by the increased availability of DSW, with a slightly positive balance of 3.5 m3/ha. This could be significant considering the large amount of old-growth stands in this part of the boreal forest.

Sign in / Sign up

Export Citation Format

Share Document