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Dominique Gravel - One of the best experts on this subject based on the ideXlab platform.
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effect of a major Ice Storm on understory light conditions in an old growth acer fagus forest pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving <2%PPFD. The Ice Storm led to a synchronized increase of the light levels at almost all understory locations, which might allow a high proportion of the advanced regeneration to experience a release. However, due to the rapid recovery of the light conditions to levels similar or lower than before the Ice Storm, this disturbance should be more advantageous to shade-tolerant species.
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Effect of a major Ice Storm on understory light conditions in an old-growth Acer–Fagus forest: Pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving
Christian Messier - One of the best experts on this subject based on the ideXlab platform.
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effect of a major Ice Storm on understory light conditions in an old growth acer fagus forest pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving <2%PPFD. The Ice Storm led to a synchronized increase of the light levels at almost all understory locations, which might allow a high proportion of the advanced regeneration to experience a release. However, due to the rapid recovery of the light conditions to levels similar or lower than before the Ice Storm, this disturbance should be more advantageous to shade-tolerant species.
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Effect of a major Ice Storm on understory light conditions in an old-growth Acer–Fagus forest: Pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving
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Analysis of deciduous tree species dynamics after a severe Ice Storm using SORTIE model simulations
Ecological Modelling, 2005Co-Authors: M. Tremblay, Christian Messier, Danielle J. MarceauAbstract:Ice Storms are frequent natural disturbance events in hardwood forests of eastern Canada and the United States, but their effects on forest dynamics are not well understood. Our objectives were to characterize short- and long-term tree species dynamics after a severe Ice Storm, and to assess the influence of spatial distribution of trees on these dynamics. SORTIE, a spatially explicit individual tree-based forest model, was used to simulate the effects of a severe Ice Storm on 300 years old stands. Crown radius was reduced and tree mortality was increased for a 5-year period following the Ice Storm disturbance. To investigate the influence of the spatial distribution of trees, we repeated the same experiment in a uniformly distributed stand where we systematically assigned coordinates of all trees, saplings and seedlings before the Ice Storm was modeled. Our results showed that six types of dynamics can be adopted by a species following an Ice Storm and that spatial distribution of trees influenced the species responses. In summary, we found that a combination of factors, namely, species density and spatial distribution, shade tolerance, growth rate, extent of canopy openness and canopy loss resulting from the Ice Storm, determine how tree species respond to Ice Storm disturbance.
Charles W. Lafon - One of the best experts on this subject based on the ideXlab platform.
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a csr classification of tree life history strategies and implications for Ice Storm damage
Oikos, 2013Co-Authors: Carissa L Wonkka, Charles W. Lafon, Craig M Hutton, Audrey JoslinAbstract:Differences in life history strategy influence the ecological roles of plant species, including their susceptibility to disturbance events. According to Grime’s CSR model, plants exhibit three primary strategies, which reflect tradeoffs between stress and disturbance. Here we classify eastern North American tree species into life history strategies on the basis of the CSR model. Then, using data on Ice Storm damage to trees, we investigate how the level of damage varied among the different CSR categories. We used tree damage data for almost 2000 individual trees representing 30 species collected during two Ice Storms in the Appalachian Mountains. We augmented the study with Ice damage data gleaned from nine published Ice-Storm studies containing over 30 000 individuals representing 22 species. The trees we identified as stress-tolerators (S) consistently sustained less damage than the other species. This finding matches the stress-tolerant strategy: damageresistance is imperative for the persistence of trees that exhibit slow growth, low reproductive capacity and long lifespan. Our analyses also suggest that competitors (C) suffer widespread damage, particularly branch breakage, but experience low mortality. This pattern likely reflects features of the competitive strategy, such as wood strength and canopy form, which preclude resistance to damage but facilitate rapid recovery. The Ice damage datasets did not contain trees that we classified as ruderals (R). Competitive ruderals (C-R) and stress-tolerant ruderals (S-R), however, sustained heavy damage and high mortality, consistent with low investment in tree defense and a prioritization of reproduction. Our analyses suggest the usefulness of the CSR model for interpreting forest dynamics and understanding the implications of tree life-history strategies for forest disturbance responses.
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Ice-Storm disturbance and long-term forest dynamics in the Adirondack Mountains
Journal of Vegetation Science, 2004Co-Authors: Charles W. LafonAbstract:Abstract Ice Storms cause periodic disturbance to temperate forests of eastern North America. They are the primary agents of disturbance in some eastern forests. In this paper, a forest gap model is employed to explore consequences of Ice Storms for the long-term dynamics of Tsuga canadensis-northern hardwoods forests. The gap model LINKAGES was modified to simulate periodic Ice Storm disturbance in the Adirondack Mountains of New York. To adapt the gap model for this purpose, field data on Ice Storm disturbance are used to develop a polytomous logistic regression model of tree damage. The logistic regression model was then incorporated into the modified forest gap model, LINKADIR, to determine the type of damage sustained by each simulated tree. The logistic regression model predicts high probabilities of bent boles or severe bole damage (leaning, snapping, or uprooting) in small-diameter trees, and increasing probability of canopy damage as tree size increases. Canopy damage is most likely on gentle slo...
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Using dendrochronology to identify major Ice Storm events in oak forests of southwestern Virginia
Climate Research, 2002Co-Authors: Charles W. Lafon, James H. SpeerAbstract:Major Ice Storms are significant forest disturbance agents and natural hazards in east- ern North America. Studies of forest damage suggest that Ice Storm severity varies among topo- graphic positions, but little climatic information is available to evaluate fine-scale variations in Ice Storm climatology. Our study assesses the utility of tree-ring analysis for identifying fine-scale spatial patterns and long-term temporal variations in the frequency of major Ice Storms. We looked for Ice Storm signals in tree-ring chronologies of chestnut oak Quercus prinus L. and black oak Q. velutina Lam. at 2 sites in southwestern Virginia that were affected by known Ice Storms in 1979 and 1994. Radial growth of these species exhibits a dual response to Ice Storm disturbance. Trees with substan- tial canopy loss show reduced radial growth for several years following an Ice Storm. Other trees dis- play increased growth due to the loss of competitors. We identified thresholds of ring-width increase and decrease that distinguished Ice Storms from other events, permitting a preliminary attempt to reconstruct Ice Storm history at each of the 2 study sites. For our Gap Mountain site, ring-width chronologies spanning the period 1914-1998 record apparent signals of major Ice Storms in 1920, 1979, and 1994. For the Walker Mountain site, our results suggest that during the period 1901-1998 the stand was affected by major Ice Storms in 1918 and 1994. This study suggests that den- drochronology provides a promising method for understanding fine-scale spatial patterns of Ice Storm disturbance in hardwood forests.
Jacques Brisson - One of the best experts on this subject based on the ideXlab platform.
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Long-term impact of a major Ice Storm on tree mortality in an old-growth forest
Forest Ecology and Management, 2019Co-Authors: Élise Deschênes, Marie‐hélène Brice, Jacques BrissonAbstract:Abstract In January 1998, eastern North America experienced the worst Ice Storm ever recorded, which resulted in major damage to forests throughout the region. However, we know little about the long-term effects of such a severe weather event, or how its potential interaction with other biotic factors impacted tree mortality. In this study, we investigated the long-term influence of the 1998 Ice Storm on tree mortality in Boise-des-Muir ecological reserve, an old-growth forest in southern Quebec (Canada). Mortality rates for four out of the five tree species studied showed a striking increase a few years after the Ice Storm, between 2000 and 2004. After this peak, tree mortality rates remained higher than before 1998. These results indicate a lagged and persistent effect of the Ice Storm on tree mortality and suggest that the tree community of Boise-des-Muir was more severely impacted than previously reported. Tree species were differentially damaged by the Ice Storm, and more than 25% of all tree species lost more than half their crown. Using a Cox proportional hazard model, we evaluated the impact of different levels of initial canopy damage from the Ice Storm on long-term tree mortality while taking into account other important biotic factors, such as tree size, tree density, indIces of species-specific competition, and the presence of the beech scale insect. Species differed in their response to the Storm, suggesting fundamental differences in sensitivity to extreme weather events. In particular, eastern hop-hornbeam (Ostrya virginiana) and American beech (Fagus grandifolia) were the species most vulnerable to the Ice Storm, and severe canopy loss led to a large increase in mortality risk. These findings suggest that the difference in tree survival following a natural disturbance likely depends not only on the severity of the damage itself, but also on species-specific ability to repair injuries and maintain physiological processes. We also found that tree size and species-specific competition influenced tree mortality significantly but did not interact with level of canopy loss. Consequently, multiple biotic factors remain important to explain mortality even after a major disturbance and should be considered when evaluating tree mortality. Our results show that the impact of the Ice Storm on tree mortality was species-specific, lagged and persisted for several years after the disturbance, potentially resulting in long-term compositional changes in the forest. This underscores the necessity of conducting long-term monitoring studies to understand the complete impacts of Ice Storms and other extreme climatic events on forests.
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effect of a major Ice Storm on understory light conditions in an old growth acer fagus forest pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving <2%PPFD. The Ice Storm led to a synchronized increase of the light levels at almost all understory locations, which might allow a high proportion of the advanced regeneration to experience a release. However, due to the rapid recovery of the light conditions to levels similar or lower than before the Ice Storm, this disturbance should be more advantageous to shade-tolerant species.
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Effect of a major Ice Storm on understory light conditions in an old-growth Acer–Fagus forest: Pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving
Marilou Beaudet - One of the best experts on this subject based on the ideXlab platform.
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effect of a major Ice Storm on understory light conditions in an old growth acer fagus forest pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving <2%PPFD. The Ice Storm led to a synchronized increase of the light levels at almost all understory locations, which might allow a high proportion of the advanced regeneration to experience a release. However, due to the rapid recovery of the light conditions to levels similar or lower than before the Ice Storm, this disturbance should be more advantageous to shade-tolerant species.
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Effect of a major Ice Storm on understory light conditions in an old-growth Acer–Fagus forest: Pattern of recovery over seven years
Forest Ecology and Management, 2007Co-Authors: Marilou Beaudet, Christian Messier, Jacques Brisson, Dominique GravelAbstract:We evaluated the effects of a major Ice Storm on understory light conditions (%PPFD, photosynthetic photon flux density) in an old-growth Acer-Fagus forest in Quebec, based on pre- and post-disturbance light measurements taken until the seventh growing season after the event (which occurred in January 1998). Before the Ice Storm, most microsites received between 2 and 4%PPFD. Following the Ice Storm, the stand-level mean %PPFD increased four- to five-fold, ranging from 13.8 to 20.5%PPFD, from 0.3 to 4 m aboveground. Despite its magnitude, the post-Ice Storm increase in light transmission was short-lived. By 1999 (2-year+), the mean light levels had decreased by half, and recovery to pre-Storm conditions occurred within 3-7 years, depending on height. The decrease in light transmission during the post-disturbance years followed an inverse J-shape trend, indicating more dynamic changes early after disturbance. By 2004 (7-year+), light levels at ≤2 m had become slightly but significantly lower than before the Ice Storm, with most microsites receiving
