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P. B. Reich - One of the best experts on this subject based on the ideXlab platform.
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Are shade tolerance, survival, and growth linked? Low light and nitrogen effects on hardwood seedlings
Ecology, 1996Co-Authors: M. B. Walters, P. B. ReichAbstract:Variation in shade tolerance is a primary mechanism driving succession in northern deciduous forests. However, little is known about interspecific differences in the traits responsible for shade tolerance. Is shade tolerance due to the ability to grow or survive in deep shade, or both? How do plant morphology and photosynthesis relate to growth in shade? Is low light the sole critical stress determining differences in "shade tolerance" or do belowground resources interact with low light to affect growth and survival? In this study we address these questions for seedlings of Betula papyrifera Marsh., Betula al- leghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quer- cus rubra L. grown for 2 yr in outdoor shade houses in a complete factorial of low light (2 and 8% open sky) and nitrogen (forest soil and forest soil plus 200 kg N.ha-'.yr-'). For these seedlings we examined effects of light and nitrogen on the interrelationships among survival, growth, and shade tolerance and explored the physiological bases of shade tol- erance by examining the relationship of plant morphology and photosynthesis to growth. Nitrogen amendments did not have a significant effect on any plant trait at either light level. In 8% light, growth and survival were highest for shade-intolerant Betula papyrifera and mid-tolerant Betula alleghaniensis, lower for shade-tolerant Ostrya and Acer, and lowest for disturbance-adapted Quercus. In 2% light, species rankings reversed as Ostrya and Acer had higher growth and survival than the other species. Second-year survival was strongly related to 1st-yr growth (P < 0.001), whereas relationships with 1st-yr plant mass and 1st- yr absolute growth rates were weak. Therefore, survival of shade-tolerant species at 2% light was related to their maintenance of positive growth, whereas intolerant species had growth near zero and high rates of mortality. In both 2 and 8% light photosynthetic rates on mass (but not area) bases and the proportion of the plant in leaves (leaf area ratio and leaf mass ratio) were positively related to growth. Greater rates of growth and survival for shade-tolerant species in very low light, and for intolerant species in higher light, suggest that there is a species-based trade-off between maximizing growth in high light and min- imizing the light compensation point for growth. This trade-off may be an important mech- anism driving forest community dynamics in northern hardwood forests.
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Growth, biomass distribution and CO_2 exchange of northern hardwood seedlings in high and low light: relationships with successional status and shade tolerance
Oecologia, 1993Co-Authors: M. B. Walters, E. L. Kruger, P. B. ReichAbstract:The physiology, morphology and growth of first-year Betula papyrifera Marsh., Betula alleghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quercus rubra L. seedlings, which differ widely in reported successional affinity and shade tolerance, were compared in a controlled high-resource environment. Relative to late-successional, shade-tolerant Acer and Ostrya species, early-successional, shade-intolerant Betula species had high relative growth rates (RGR) and high rates of photosynthesis, nitrogen uptake and respiration when grown in high light. Fire-adapted Quercus rubra had intermediate photosynthetic rates, but had the lowest RGR and leaf area ratio and the highest root weight ratio of any species. Interspecific variation in RGR in high light was positively correlated with allocation to leaves and rates of photosynthesis and respiration, and negatively related to seed mass and leaf mass per unit area. Despite higher respiration rates, early-successional Betula papyrifera lost a lower percentage of daily photosynthetic CO_2 gain to respiration than other species in high light. A subset comprised of the three Betulaceae family members was also grown in low light. As in high light, low-light grown Betula species had higher growth rates than tolerant Ostrya virainiana . The rapid growth habit of sarly-successional species in low light was associated with a higher proportion of biomass distributed to leaves, lower leaf mass per unit area, a lower proportion of biomass in roots, and a greater height per unit stem mass. Variation in these traits is discussed in terms of reported species ecologies in a resource availability context.
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Growth, biomass distribution and CO2 exchange of northern hardwood seedlings in high and low light: relationships with successional status and shade tolerance.
Oecologia, 1993Co-Authors: M. B. Walters, E. L. Kruger, P. B. ReichAbstract:The physiology, morphology and growth of first-year Betula papyrifera Marsh., Betula alleghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quercus rubra L. seedlings, which differ widely in reported successional affinity and shade tolerance, were compared in a controlled high-resource environment. Relative to late-successional, shade-tolerant Acer and Ostrya species, early-successional, shade-intolerant Betula species had high relative growth rates (RGR) and high rates of photosynthesis, nitrogen uptake and respiration when grown in high light. Fire-adapted Quercus rubra had intermediate photosynthetic rates, but had the lowest RGR and leaf area ratio and the highest root weight ratio of any species. Interspecific variation in RGR in high light was positively correlated with allocation to leaves and rates of photosynthesis and respiration, and negatively related to seed mass and leaf mass per unit area. Despite higher respiration rates, early-successional Betula papyrifera lost a lower percentage of daily photosynthetic CO2 gain to respiration than other species in high light. A subset comprised of the three Betulaceae family members was also grown in low light. As in high light, low-light grown Betula species had higher growth rates than tolerant Ostrya virainiana. The rapid growth habit of sarly-successional species in low light was associated with a higher proportion of biomass distributed to leaves, lower leaf mass per unit area, a lower proportion of biomass in roots, and a greater height per unit stem mass. Variation in these traits is discussed in terms of reported species ecologies in a resource availability context.
M. B. Walters - One of the best experts on this subject based on the ideXlab platform.
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Are shade tolerance, survival, and growth linked? Low light and nitrogen effects on hardwood seedlings
Ecology, 1996Co-Authors: M. B. Walters, P. B. ReichAbstract:Variation in shade tolerance is a primary mechanism driving succession in northern deciduous forests. However, little is known about interspecific differences in the traits responsible for shade tolerance. Is shade tolerance due to the ability to grow or survive in deep shade, or both? How do plant morphology and photosynthesis relate to growth in shade? Is low light the sole critical stress determining differences in "shade tolerance" or do belowground resources interact with low light to affect growth and survival? In this study we address these questions for seedlings of Betula papyrifera Marsh., Betula al- leghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quer- cus rubra L. grown for 2 yr in outdoor shade houses in a complete factorial of low light (2 and 8% open sky) and nitrogen (forest soil and forest soil plus 200 kg N.ha-'.yr-'). For these seedlings we examined effects of light and nitrogen on the interrelationships among survival, growth, and shade tolerance and explored the physiological bases of shade tol- erance by examining the relationship of plant morphology and photosynthesis to growth. Nitrogen amendments did not have a significant effect on any plant trait at either light level. In 8% light, growth and survival were highest for shade-intolerant Betula papyrifera and mid-tolerant Betula alleghaniensis, lower for shade-tolerant Ostrya and Acer, and lowest for disturbance-adapted Quercus. In 2% light, species rankings reversed as Ostrya and Acer had higher growth and survival than the other species. Second-year survival was strongly related to 1st-yr growth (P < 0.001), whereas relationships with 1st-yr plant mass and 1st- yr absolute growth rates were weak. Therefore, survival of shade-tolerant species at 2% light was related to their maintenance of positive growth, whereas intolerant species had growth near zero and high rates of mortality. In both 2 and 8% light photosynthetic rates on mass (but not area) bases and the proportion of the plant in leaves (leaf area ratio and leaf mass ratio) were positively related to growth. Greater rates of growth and survival for shade-tolerant species in very low light, and for intolerant species in higher light, suggest that there is a species-based trade-off between maximizing growth in high light and min- imizing the light compensation point for growth. This trade-off may be an important mech- anism driving forest community dynamics in northern hardwood forests.
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Growth, biomass distribution and CO_2 exchange of northern hardwood seedlings in high and low light: relationships with successional status and shade tolerance
Oecologia, 1993Co-Authors: M. B. Walters, E. L. Kruger, P. B. ReichAbstract:The physiology, morphology and growth of first-year Betula papyrifera Marsh., Betula alleghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quercus rubra L. seedlings, which differ widely in reported successional affinity and shade tolerance, were compared in a controlled high-resource environment. Relative to late-successional, shade-tolerant Acer and Ostrya species, early-successional, shade-intolerant Betula species had high relative growth rates (RGR) and high rates of photosynthesis, nitrogen uptake and respiration when grown in high light. Fire-adapted Quercus rubra had intermediate photosynthetic rates, but had the lowest RGR and leaf area ratio and the highest root weight ratio of any species. Interspecific variation in RGR in high light was positively correlated with allocation to leaves and rates of photosynthesis and respiration, and negatively related to seed mass and leaf mass per unit area. Despite higher respiration rates, early-successional Betula papyrifera lost a lower percentage of daily photosynthetic CO_2 gain to respiration than other species in high light. A subset comprised of the three Betulaceae family members was also grown in low light. As in high light, low-light grown Betula species had higher growth rates than tolerant Ostrya virainiana . The rapid growth habit of sarly-successional species in low light was associated with a higher proportion of biomass distributed to leaves, lower leaf mass per unit area, a lower proportion of biomass in roots, and a greater height per unit stem mass. Variation in these traits is discussed in terms of reported species ecologies in a resource availability context.
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Growth, biomass distribution and CO2 exchange of northern hardwood seedlings in high and low light: relationships with successional status and shade tolerance.
Oecologia, 1993Co-Authors: M. B. Walters, E. L. Kruger, P. B. ReichAbstract:The physiology, morphology and growth of first-year Betula papyrifera Marsh., Betula alleghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quercus rubra L. seedlings, which differ widely in reported successional affinity and shade tolerance, were compared in a controlled high-resource environment. Relative to late-successional, shade-tolerant Acer and Ostrya species, early-successional, shade-intolerant Betula species had high relative growth rates (RGR) and high rates of photosynthesis, nitrogen uptake and respiration when grown in high light. Fire-adapted Quercus rubra had intermediate photosynthetic rates, but had the lowest RGR and leaf area ratio and the highest root weight ratio of any species. Interspecific variation in RGR in high light was positively correlated with allocation to leaves and rates of photosynthesis and respiration, and negatively related to seed mass and leaf mass per unit area. Despite higher respiration rates, early-successional Betula papyrifera lost a lower percentage of daily photosynthetic CO2 gain to respiration than other species in high light. A subset comprised of the three Betulaceae family members was also grown in low light. As in high light, low-light grown Betula species had higher growth rates than tolerant Ostrya virainiana. The rapid growth habit of sarly-successional species in low light was associated with a higher proportion of biomass distributed to leaves, lower leaf mass per unit area, a lower proportion of biomass in roots, and a greater height per unit stem mass. Variation in these traits is discussed in terms of reported species ecologies in a resource availability context.
Richard K. Kobe - One of the best experts on this subject based on the ideXlab platform.
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Average seedling height (± SE) per site, at the start of each year, for seedlings of six northern hardwood species.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:The outbreak occurred in 2009. Note the different scales on the y-axis. A) acru = Acer rubrum (n = 22–32, per site); B) acsa = Acer saccharum (n = 16–59, per site); C) fagr = Fagus grandifolia (n = 34–53, per site); D) fram = Fraxinus americana (n = 9–62, per site); E) osvi = Ostrya virginiana (n = 9–13, per site); F) prse = Prunus serotina (n = 13–21, per site).
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Linear mixed-effects model results of seedling height growth as a function of site, year and seedling height at the start of the growing season for six northern hardwood species.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:Per species, only models within two AICc (Akaike’s Information Criterion) units from the best model are included. The deviation from the best model in AICc units (ΔAICc) is indicated. n indicates the number of included seedlings per species. The marginal (m) R2 (fixed effects only), and the conditional (c) R2 (both fixed and random effects) are indicated. acru = Acer rubrum; acsa = Acer saccharum; fagr = Fagus grandifolia; fram = Fraxinus americana; osvi = Ostrya virginiana; prse = Prunus serotina.
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Predicted seedling height growth for seedlings of six northern hardwood species in response to a forest tent caterpillar outbreak.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:Back-transformed mean (± SE) predicted height growth per site, per year, while holding seedling height constant at a species-specific average across all sites and years. The outbreak occurred in 2009. Note the different scales on the y-axis. A) acru = Acer rubrum (n = 22–32, per site); B) acsa = Acer saccharum (n = 16–59, per site); C) fagr = Fagus grandifolia (n = 34–53, per site); D) fram = Fraxinus americana (n = 9–62, per site); E) osvi = Ostrya virginiana (n = 9–13, per site); F) prse = Prunus serotina (n = 13–21, per site).
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Description of the six defoliated study sites and species for which seedlings were included.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:Land form, location, estimated defoliation level (in 2009), dominant species in the overstory (the three most abundant species based on stems ≥ 10 cm diameter at breast height; Baribault et al. [27]), and species for which seedlings were included are indicated. Site numbers generally correspond to the numbering in Baribault et al. [27], except for sites 12 and 13, which were merged into one site (site 12). acru = Acer rubrum; acsa = Acer saccharum; fagr = Fagus grandifolia; fram = Fraxinus americana; osvi = Ostrya virginiana; piba = Pinus banksiana; pogr = Populus grandidentata; prse = Prunus serotina; qual = Quercus alba; quru = Quercus rubra; quve = Quercus velutina; tiam = Tilia americana.
E. L. Kruger - One of the best experts on this subject based on the ideXlab platform.
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Growth, biomass distribution and CO_2 exchange of northern hardwood seedlings in high and low light: relationships with successional status and shade tolerance
Oecologia, 1993Co-Authors: M. B. Walters, E. L. Kruger, P. B. ReichAbstract:The physiology, morphology and growth of first-year Betula papyrifera Marsh., Betula alleghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quercus rubra L. seedlings, which differ widely in reported successional affinity and shade tolerance, were compared in a controlled high-resource environment. Relative to late-successional, shade-tolerant Acer and Ostrya species, early-successional, shade-intolerant Betula species had high relative growth rates (RGR) and high rates of photosynthesis, nitrogen uptake and respiration when grown in high light. Fire-adapted Quercus rubra had intermediate photosynthetic rates, but had the lowest RGR and leaf area ratio and the highest root weight ratio of any species. Interspecific variation in RGR in high light was positively correlated with allocation to leaves and rates of photosynthesis and respiration, and negatively related to seed mass and leaf mass per unit area. Despite higher respiration rates, early-successional Betula papyrifera lost a lower percentage of daily photosynthetic CO_2 gain to respiration than other species in high light. A subset comprised of the three Betulaceae family members was also grown in low light. As in high light, low-light grown Betula species had higher growth rates than tolerant Ostrya virainiana . The rapid growth habit of sarly-successional species in low light was associated with a higher proportion of biomass distributed to leaves, lower leaf mass per unit area, a lower proportion of biomass in roots, and a greater height per unit stem mass. Variation in these traits is discussed in terms of reported species ecologies in a resource availability context.
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Growth, biomass distribution and CO2 exchange of northern hardwood seedlings in high and low light: relationships with successional status and shade tolerance.
Oecologia, 1993Co-Authors: M. B. Walters, E. L. Kruger, P. B. ReichAbstract:The physiology, morphology and growth of first-year Betula papyrifera Marsh., Betula alleghaniensis Britton, Ostrya virginiana (Mill.) K. Koch, Acer saccharum Marsh., and Quercus rubra L. seedlings, which differ widely in reported successional affinity and shade tolerance, were compared in a controlled high-resource environment. Relative to late-successional, shade-tolerant Acer and Ostrya species, early-successional, shade-intolerant Betula species had high relative growth rates (RGR) and high rates of photosynthesis, nitrogen uptake and respiration when grown in high light. Fire-adapted Quercus rubra had intermediate photosynthetic rates, but had the lowest RGR and leaf area ratio and the highest root weight ratio of any species. Interspecific variation in RGR in high light was positively correlated with allocation to leaves and rates of photosynthesis and respiration, and negatively related to seed mass and leaf mass per unit area. Despite higher respiration rates, early-successional Betula papyrifera lost a lower percentage of daily photosynthetic CO2 gain to respiration than other species in high light. A subset comprised of the three Betulaceae family members was also grown in low light. As in high light, low-light grown Betula species had higher growth rates than tolerant Ostrya virainiana. The rapid growth habit of sarly-successional species in low light was associated with a higher proportion of biomass distributed to leaves, lower leaf mass per unit area, a lower proportion of biomass in roots, and a greater height per unit stem mass. Variation in these traits is discussed in terms of reported species ecologies in a resource availability context.
Danaë M. A. Rozendaal - One of the best experts on this subject based on the ideXlab platform.
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Average seedling height (± SE) per site, at the start of each year, for seedlings of six northern hardwood species.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:The outbreak occurred in 2009. Note the different scales on the y-axis. A) acru = Acer rubrum (n = 22–32, per site); B) acsa = Acer saccharum (n = 16–59, per site); C) fagr = Fagus grandifolia (n = 34–53, per site); D) fram = Fraxinus americana (n = 9–62, per site); E) osvi = Ostrya virginiana (n = 9–13, per site); F) prse = Prunus serotina (n = 13–21, per site).
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Linear mixed-effects model results of seedling height growth as a function of site, year and seedling height at the start of the growing season for six northern hardwood species.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:Per species, only models within two AICc (Akaike’s Information Criterion) units from the best model are included. The deviation from the best model in AICc units (ΔAICc) is indicated. n indicates the number of included seedlings per species. The marginal (m) R2 (fixed effects only), and the conditional (c) R2 (both fixed and random effects) are indicated. acru = Acer rubrum; acsa = Acer saccharum; fagr = Fagus grandifolia; fram = Fraxinus americana; osvi = Ostrya virginiana; prse = Prunus serotina.
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Predicted seedling height growth for seedlings of six northern hardwood species in response to a forest tent caterpillar outbreak.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:Back-transformed mean (± SE) predicted height growth per site, per year, while holding seedling height constant at a species-specific average across all sites and years. The outbreak occurred in 2009. Note the different scales on the y-axis. A) acru = Acer rubrum (n = 22–32, per site); B) acsa = Acer saccharum (n = 16–59, per site); C) fagr = Fagus grandifolia (n = 34–53, per site); D) fram = Fraxinus americana (n = 9–62, per site); E) osvi = Ostrya virginiana (n = 9–13, per site); F) prse = Prunus serotina (n = 13–21, per site).
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Description of the six defoliated study sites and species for which seedlings were included.
2016Co-Authors: Danaë M. A. Rozendaal, Richard K. KobeAbstract:Land form, location, estimated defoliation level (in 2009), dominant species in the overstory (the three most abundant species based on stems ≥ 10 cm diameter at breast height; Baribault et al. [27]), and species for which seedlings were included are indicated. Site numbers generally correspond to the numbering in Baribault et al. [27], except for sites 12 and 13, which were merged into one site (site 12). acru = Acer rubrum; acsa = Acer saccharum; fagr = Fagus grandifolia; fram = Fraxinus americana; osvi = Ostrya virginiana; piba = Pinus banksiana; pogr = Populus grandidentata; prse = Prunus serotina; qual = Quercus alba; quru = Quercus rubra; quve = Quercus velutina; tiam = Tilia americana.
