The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Bernard Prévosto - One of the best experts on this subject based on the ideXlab platform.
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Influence of nurse birch and Scots pine seedlings on early aerial development of European Beech seedlings in an open-field plantation of Central France
Forestry, 2007Co-Authors: Bernard Prévosto, Philippe BalandierAbstract:Beech woodland can be restored by direct planting of Beech (Fagus sylvatica L.) seedlings in abandoned areas, but this method is generally avoided in forestry because of the growth difficulties of Beech in full-light conditions. This study tested a method that consists of planting Beech seedlings in full-light conditions with silver birch (Betula pendula Roth.) or Scots pine (Pinus sylvestris L.) as nurse trees. A total of 65 two-year-old Beech seedlings surrounded by either 3, 4, 5 or 6 pine or birch seedlings or without competitors were planted in bare-soil open-field conditions in Central France. Tree growth and light availability were monitored at the end of each of the following 3 years, and soil moisture was also measured the last year. At the end of the experiment, aerial biomass measurements were made on the Beeches. Results showed that relative Beech growth in terms of diameter was significantly reduced by the local neighbouring trees and that this reduction was particularly noticeable in the pine treatments where there was extensive pine seedling development. In contrast, relative Beech height did not exhibit any significant variations among the treatments. Light availability was decreased by the neighbouring trees, especially in the pine treatments. Light reduction was more pronounced in the last 2 years and in the middle or lower parts of the canopy of the subject Beech. Soil water content was lower under the pine canopies than under the birch canopies, and was positively correlated to Beech relative diameter growth. Specific leaf area, height-to-diameter ratio and crown length-to-crown width ratio weakly but significantly increased with competition from the neighbours. Beech biomass partitioning was only weakly affected by the treatments. This study showed that nurse trees tend to reduce Beech growth but improve form although effects remained weak due to the insufficient length of the experiment. Further studies are also needed to quantify the effects of the neighbourhood on the growth of competitive herbaceous vegetation and on changes in the microclimatic conditions.
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Influence of nurse birch and Scots pine seedlings on early aerial development of European Beech seedlings in an open-field plantation of central France
Forestry, 2007Co-Authors: Bernard Prévosto, Philippe BalandierAbstract:Beech woodland can be restored by direct planting of Beech (Fagus sylvatica L.) seedlings in abandoned areas, but this method is generally avoided in forestry because of the growth difficulties of Beech in full light conditions. This study tested a method that consists in planting Beech seedlings in full-light conditions with Silver birch or Scots pine as nurse trees. A total of 65 two-year-old Beech seedlings surrounded by either 3, 4, 5 or 6 pine or birch seedlings or without competitors were planted in bare-soil open-field conditions in central France. Tree growth and light availability were monitored at the end of each of the 3 years, and soil moisture was also measured the last year. At the end of the experiment, aerial biomass measurements were made on the Beeches. Results showed that relative Beech growth in terms of diameter was reduced by the local neighbourhood and that this reduction was particularly noticeable in the pine treatments where there was extensive pine seedling development. In contrast, relative Beech height did not exhibit any significant variations among the treatments. Light availability was decreased by the neighbourhood, especially in the pine treatments. Light reduction was more pronounced in the last two years and in the middle or lower parts of the canopy of the subject Beech. Soil water content was lower under the pine canopies than under the birch canopies, and was positively correlated to Beech relative diameter growth. SLA, height-to-diameter ratio and crown length-to-crown width ratio increased with increasing competition from the neighbours. There were treatment effects on Beech biomass partitioning: the branch biomass-to-total biomass ratio was lower in the pine treatment than in the birch treatment, whereas stem-to-total biomass ratio was lower in the birch treatment. This study showed that nurse trees tend to reduce Beech growth but improve form. However, further studies are needed to quantify the effects of the neighbourhood on the growth of competitive herbaceous vegetation and on changes in the microclimatic conditions.
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Dimensional relationships of naturally established European Beech trees beneath Scots pine and Silver birch canopy
Forest Ecology and Management, 2004Co-Authors: Bernard Prévosto, T. CurtAbstract:Huge areas of the mid-elevation mountains of the French Massif central were abandoned by agriculture after grazing abandonment. They were colonized by pioneer trees, like Scots pine and Silver birch, that have formed monospecific stands in the space of a few years. In such stands Beech (Fagus sylvatica L.), a late-sucessional species, has been established naturally.In order to study Beech growth and development, Beech trees of various ages were sampled under birch and Scots pine canopy. Dimensions, age, radial and height growth of the subject Beech tree and dimensions of branches at the top of the canopy were measured. Local competition around each Beech was assessed with competition indices and below-ground competition was quantified by root biomass measurements.Despite slightly greater light availability under birch than under Scots pine, Beech saplings exhibited superior growth and dimensions at a given age under Scots pine than under birch. However, this trend tended to decrease while Beech was aging and started penetrating into the upper tree layer. Although, competition index values were significantly different between birch and Scots pine stands, growth or size were reduced by competition in the same proportions when comparing the two types of cover. Beech fine root biomass was comparable for young and intermediate trees, whereas fine root biomass of both competitor trees and ground vegetation was clearly more abundant under birch. Lastly, branching pattern only exhibited significant differences for young trees, branches were more vertically distributed and of lower dimensions beneath birch canopy than beneath pine canopy. We concluded that Beech growth was, in the first stage, more limited under birch than under pine due to a higher below-ground competition.
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Rooting strategy of naturally regenerated Beech in Silver birch and Scots pine woodlands
Plant and Soil, 2003Co-Authors: T. Curt, Bernard PrévostoAbstract:This study investigated the belowground development and strategy of late-successional European Beech (Fagussylvatica L.) in ageing natural Scots pine (Pinus sylvestris L.) and Silver birch (Betula pendula Roth.) woodlandsin a French volcanic mid-elevation area. For this purpose root biomass, root profile and fine-root architecture ofcompetitor trees were examined in 53 mixed pine-Beech and 42 birch-Beech woodlands along a stand maturationgradient, using the root auger technique (0-75-cm). The total Beech fine-root biomass highly correlated withaerial dimensions such as stem height and girth, whereas it moderately correlated with its age, thus indicatingthe effects of competition. Basic stand biometric data such as stand density and basal area had no significant effecton Beech root biomass. Conversely, competition indices taking into account the vertical dimensions of competitortrees were efficient, probably due to redundancy with Beech height. At similar age and height, Beeches underbirch had a greater belowground development than Beeches under pine. Each species exhibited specific rootingpattern and plasticity of fine-root architecture along the gradients of stand maturation and competition. Beech hada heart-shaped rooting habit in both mixings, which strongly increased along stand maturation. Its fine-root systemadopted a foraging strategy to respond to increasing stand competition. The Scots pine fine-root system was platelikeand showed a low morphological plasticity, thus presumably a conservative strategy. Silver birch exhibiteda high biomass and a foraging capacity in the topsoil but a loose root system in the subsoil. The coexistence ofpine and Beech roots in the upper soil presumably leads to a high belowground competition. Beech root systembecomes predominant throughout the soil profile and it adopts an efficient foraging strategy, but at the expense ofits belowground development. Conversely, the niche partitioning strategy between Beech and birch may explainwhy Beech develops strongly belowground in spite of the fact that birch has a dense rooting and a competitivefine-root architecture. As a consequence, Beech mid-term regeneration and development may be facilitated underbirch as compared with pine.
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Competition for water between Beech seedlings and surrounding vegetation in different light and vegetation composition conditions
Annals of Forest Science, 2003Co-Authors: Lluis Coll, Bernard Prévosto, Philippe Balandier, Catherine Picon-cochard, Thomas CurtAbstract:To gain a better understanding of Beech growth requirements and assess the competition with the surrounding vegetation at two successional stages after agricultural land abandonment, we introduced two-year-old Beech seedlings (i) in a recently abandoned meadow (one half weeded) and (ii) in an old meadow colonised by 25-year-old natural Scots pine, with one part thinned to increase light availability at ground level. Beech seedlings presented significantly different stem diameter growth rates according to vegetation composition (grasses or dicotyledon species) and light availability for both successional stages. Grass species, which developed efficient strategies to extract soil water, competed strongly with Beech seedling compared with dicotyledon species. Water competition led to a strong reduction of Beech diameter growth. For a given vegetation composition, increasing light availability improved Beech growth.
Philippe Balandier - One of the best experts on this subject based on the ideXlab platform.
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Height competition between Quercus petraea and Fagus sylvatica natural regeneration in mixed and uneven-aged stands
Forest Ecology and Management, 2013Co-Authors: G. Ligot, Philippe Balandier, Alexis Fayolle, P. Lejeune, H. ClaessensAbstract:The mid-successional sessile oak (Quercus petraea (Matt.) Liebl.) and the late-successional European Beech (Fagus sylvatica L.) are two major species of temperate forests. According to the literature, in mixed stands, large canopy openings should promote the growth of the light-demanding oak over the shade tolerant Beech. Nevertheless, foresters who manage mixed oak and Beech forests with continuous-cover silviculture in Western and Central Europe, face difficulties to promote the regeneration of oak. In the Belgian Ardennes, we monitored the mixed advanced regeneration of 7–13 year old oak and Beech trees scattered across 23 sites to test the hypotheses regarding the relative advantage of the two species across the light gradient, the outcome of interspecific competition exerted by neighbouring saplings, the effect of direct and diffuse radiation and the site effect. We adjusted a set of mixed non-linear models of the height growth of saplings for the two species and selected the best model for the two species. In contrast to expectations, we found that Beech saplings had the highest height growth rate at all light levels. Beech saplings reached an optimum growth at transmittance of 10%, whereas oak saplings needed more than 20%. The two species responded positively to soil richness but only oak saplings responded to direct radiation and micro-climatic variations. These results indicate that oak saplings are systematically outcompeted by Beech saplings across the light gradient. Thus, the control of canopy opening is not sufficient to promote the natural regeneration of oak beneath a stand also containing Beech in the Belgian Ardennes.
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Influence of nurse birch and Scots pine seedlings on early aerial development of European Beech seedlings in an open-field plantation of central France
Forestry, 2007Co-Authors: Bernard Prévosto, Philippe BalandierAbstract:Beech woodland can be restored by direct planting of Beech (Fagus sylvatica L.) seedlings in abandoned areas, but this method is generally avoided in forestry because of the growth difficulties of Beech in full light conditions. This study tested a method that consists in planting Beech seedlings in full-light conditions with Silver birch or Scots pine as nurse trees. A total of 65 two-year-old Beech seedlings surrounded by either 3, 4, 5 or 6 pine or birch seedlings or without competitors were planted in bare-soil open-field conditions in central France. Tree growth and light availability were monitored at the end of each of the 3 years, and soil moisture was also measured the last year. At the end of the experiment, aerial biomass measurements were made on the Beeches. Results showed that relative Beech growth in terms of diameter was reduced by the local neighbourhood and that this reduction was particularly noticeable in the pine treatments where there was extensive pine seedling development. In contrast, relative Beech height did not exhibit any significant variations among the treatments. Light availability was decreased by the neighbourhood, especially in the pine treatments. Light reduction was more pronounced in the last two years and in the middle or lower parts of the canopy of the subject Beech. Soil water content was lower under the pine canopies than under the birch canopies, and was positively correlated to Beech relative diameter growth. SLA, height-to-diameter ratio and crown length-to-crown width ratio increased with increasing competition from the neighbours. There were treatment effects on Beech biomass partitioning: the branch biomass-to-total biomass ratio was lower in the pine treatment than in the birch treatment, whereas stem-to-total biomass ratio was lower in the birch treatment. This study showed that nurse trees tend to reduce Beech growth but improve form. However, further studies are needed to quantify the effects of the neighbourhood on the growth of competitive herbaceous vegetation and on changes in the microclimatic conditions.
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Influence of nurse birch and Scots pine seedlings on early aerial development of European Beech seedlings in an open-field plantation of Central France
Forestry, 2007Co-Authors: Bernard Prévosto, Philippe BalandierAbstract:Beech woodland can be restored by direct planting of Beech (Fagus sylvatica L.) seedlings in abandoned areas, but this method is generally avoided in forestry because of the growth difficulties of Beech in full-light conditions. This study tested a method that consists of planting Beech seedlings in full-light conditions with silver birch (Betula pendula Roth.) or Scots pine (Pinus sylvestris L.) as nurse trees. A total of 65 two-year-old Beech seedlings surrounded by either 3, 4, 5 or 6 pine or birch seedlings or without competitors were planted in bare-soil open-field conditions in Central France. Tree growth and light availability were monitored at the end of each of the following 3 years, and soil moisture was also measured the last year. At the end of the experiment, aerial biomass measurements were made on the Beeches. Results showed that relative Beech growth in terms of diameter was significantly reduced by the local neighbouring trees and that this reduction was particularly noticeable in the pine treatments where there was extensive pine seedling development. In contrast, relative Beech height did not exhibit any significant variations among the treatments. Light availability was decreased by the neighbouring trees, especially in the pine treatments. Light reduction was more pronounced in the last 2 years and in the middle or lower parts of the canopy of the subject Beech. Soil water content was lower under the pine canopies than under the birch canopies, and was positively correlated to Beech relative diameter growth. Specific leaf area, height-to-diameter ratio and crown length-to-crown width ratio weakly but significantly increased with competition from the neighbours. Beech biomass partitioning was only weakly affected by the treatments. This study showed that nurse trees tend to reduce Beech growth but improve form although effects remained weak due to the insufficient length of the experiment. Further studies are also needed to quantify the effects of the neighbourhood on the growth of competitive herbaceous vegetation and on changes in the microclimatic conditions.
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Competition for water between Beech seedlings and surrounding vegetation in different light and vegetation composition conditions
Annals of Forest Science, 2003Co-Authors: Lluis Coll, Bernard Prévosto, Philippe Balandier, Catherine Picon-cochard, Thomas CurtAbstract:To gain a better understanding of Beech growth requirements and assess the competition with the surrounding vegetation at two successional stages after agricultural land abandonment, we introduced two-year-old Beech seedlings (i) in a recently abandoned meadow (one half weeded) and (ii) in an old meadow colonised by 25-year-old natural Scots pine, with one part thinned to increase light availability at ground level. Beech seedlings presented significantly different stem diameter growth rates according to vegetation composition (grasses or dicotyledon species) and light availability for both successional stages. Grass species, which developed efficient strategies to extract soil water, competed strongly with Beech seedling compared with dicotyledon species. Water competition led to a strong reduction of Beech diameter growth. For a given vegetation composition, increasing light availability improved Beech growth.
T. Curt - One of the best experts on this subject based on the ideXlab platform.
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Growth, mortality, and morphological response of European Beech and downy oak along a light gradient in sub-Mediterranean forest
Canadian Journal of Forest Research, 2005Co-Authors: Georges Kunstler, T. Curt, M. Bouchaud, Jacques LepartAbstract:We examined light as a niche partitioning factor between the late-successional European Beech (Fagus sylvatica L.) and the mid-successional downy oak (Quercus pubescens Willd.), two dominant species in the sub-Mediterranean area of southern France. For these species we estimated sapling growth models (in radius and in height) as a function of light availability. Beech had a higher growth in low light and a higher asymptotic growth rate than oak. We estimated species-specific growth-mortality functions. Beech showed a higher tolerance to slow growth than oak. By linking light-growth functions and growth-mortality functions, we found that Beech had a lower mortality at low light than oak. Beech saplings had a higher probability of survival than oak at low and at high light levels. Beech exhibited the highest plasticity of morphological traits (i.e., biomass allocation, leaf morphology, and architectural traits) as a function of light. Since Beech has higher growth and survival than oak at variable light regimes, we conclude that niche partitioning for light cannot explain the coexistence of these two species. We propose that disturbance and water stress should be explicitly taken into account to understand niche partitioning and succession in the sub- Mediterranean area.
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Dimensional relationships of naturally established European Beech trees beneath Scots pine and Silver birch canopy
Forest Ecology and Management, 2004Co-Authors: Bernard Prévosto, T. CurtAbstract:Huge areas of the mid-elevation mountains of the French Massif central were abandoned by agriculture after grazing abandonment. They were colonized by pioneer trees, like Scots pine and Silver birch, that have formed monospecific stands in the space of a few years. In such stands Beech (Fagus sylvatica L.), a late-sucessional species, has been established naturally.In order to study Beech growth and development, Beech trees of various ages were sampled under birch and Scots pine canopy. Dimensions, age, radial and height growth of the subject Beech tree and dimensions of branches at the top of the canopy were measured. Local competition around each Beech was assessed with competition indices and below-ground competition was quantified by root biomass measurements.Despite slightly greater light availability under birch than under Scots pine, Beech saplings exhibited superior growth and dimensions at a given age under Scots pine than under birch. However, this trend tended to decrease while Beech was aging and started penetrating into the upper tree layer. Although, competition index values were significantly different between birch and Scots pine stands, growth or size were reduced by competition in the same proportions when comparing the two types of cover. Beech fine root biomass was comparable for young and intermediate trees, whereas fine root biomass of both competitor trees and ground vegetation was clearly more abundant under birch. Lastly, branching pattern only exhibited significant differences for young trees, branches were more vertically distributed and of lower dimensions beneath birch canopy than beneath pine canopy. We concluded that Beech growth was, in the first stage, more limited under birch than under pine due to a higher below-ground competition.
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Rooting strategy of naturally regenerated Beech in Silver birch and Scots pine woodlands
Plant and Soil, 2003Co-Authors: T. Curt, Bernard PrévostoAbstract:This study investigated the belowground development and strategy of late-successional European Beech (Fagussylvatica L.) in ageing natural Scots pine (Pinus sylvestris L.) and Silver birch (Betula pendula Roth.) woodlandsin a French volcanic mid-elevation area. For this purpose root biomass, root profile and fine-root architecture ofcompetitor trees were examined in 53 mixed pine-Beech and 42 birch-Beech woodlands along a stand maturationgradient, using the root auger technique (0-75-cm). The total Beech fine-root biomass highly correlated withaerial dimensions such as stem height and girth, whereas it moderately correlated with its age, thus indicatingthe effects of competition. Basic stand biometric data such as stand density and basal area had no significant effecton Beech root biomass. Conversely, competition indices taking into account the vertical dimensions of competitortrees were efficient, probably due to redundancy with Beech height. At similar age and height, Beeches underbirch had a greater belowground development than Beeches under pine. Each species exhibited specific rootingpattern and plasticity of fine-root architecture along the gradients of stand maturation and competition. Beech hada heart-shaped rooting habit in both mixings, which strongly increased along stand maturation. Its fine-root systemadopted a foraging strategy to respond to increasing stand competition. The Scots pine fine-root system was platelikeand showed a low morphological plasticity, thus presumably a conservative strategy. Silver birch exhibiteda high biomass and a foraging capacity in the topsoil but a loose root system in the subsoil. The coexistence ofpine and Beech roots in the upper soil presumably leads to a high belowground competition. Beech root systembecomes predominant throughout the soil profile and it adopts an efficient foraging strategy, but at the expense ofits belowground development. Conversely, the niche partitioning strategy between Beech and birch may explainwhy Beech develops strongly belowground in spite of the fact that birch has a dense rooting and a competitivefine-root architecture. As a consequence, Beech mid-term regeneration and development may be facilitated underbirch as compared with pine.
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Root biomass and rooting profile of naturally regenerated Beech in mid-elevation Scots pine woodlands
Plant Ecology, 2003Co-Authors: T. Curt, Bernard PrévostoAbstract:The natural establishment of shade-tolerant forest species such as Beech (Fagus sylvatica L.) occurs in naturally regenerated Scots pine (Pinus sylvestris L.) woodlands that develop on former pastures and cultivated lands. To examine possible effects of underground competition in Beech establishment, we studied the root biomass and the rooting profile of 53 mixed Scots pine-natural Beech woodlands in French mid-elevation volcanic areas. Stands were arranged along a maturation gradient. Roots were sampled using the root-auger technique (0 to 75cm depth every 15 cm). In addition, 23 young Beeches were uprooted to study the entire root system. Total Beechfine-root biomass was closely correlated with most Beech aerial characteristics, (e.g., height, diameter and girth),and correlated moderately with tree age. However, it correlated poorly with basic competition indices such asstand density and basal area. Conversely, competition indices including vertical dimensions of competing trees were correlated with the underground biomass, probably as a result of redundancy with Beech height. The rooting profile (fine roots, < 5 mm) of Beech and pine were quite similar, and did not change significantly along the stand maturation gradient. Beech has a heart-shaped root system while pine is more plate-like and dimorphic. Beech fine-root biomass progressively surpassed pine biomass throughout the soil layers, thus confirming that it is dynamic and competitive in mature mixed stands. The coexistence of the root systems of Beech and pine in the same soil layers presumably results in strong underground competition.
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Root biomass and rooting patterns of naturally regenerated Beech according to a gradient of age and competition with birch and Scots
2001Co-Authors: T. Curt, Bernard Prévosto, M. Bouchaud, G. Agrech, André MarquierAbstract:We studied 53 mixed Scots pine-Beech mixed stands and 42 Silver birch-Beech mixed stands, along an stand maturation and competition gradient. In addition, 23 young Beeches were uplifted under pine and 24 under birch, in order to give real measurement of below- and aboveground biomass. Results indicate that each species presented a typical rooting habit among all stands. Beech total fine-root biomass increased markedly according to the stand maturation gradient, and thus to its age and height. Results also indicated a coexistence strategy between Beech and pine roots, which may lead in the long-term to a strong belowground competition and a reduction of root development. Conversely, we observed a tendency to a niche partitioning strategy between Beech and birch. This progressive vertical compartmentalization may allow to reduce interspecific competition between tree species. The uplifted Beeches confirmed that the Beech rooting under birch may be more favorable than under pine. In the two types of mixings, Beech total fine-root biomass highly correlated with aboveground individual parameters such as tree height and girth.
Andreas Bolte - One of the best experts on this subject based on the ideXlab platform.
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Understory dynamics after disturbance accelerate succession from spruce to Beech-dominated forest—the Siggaboda case study
Annals of Forest Science, 2014Co-Authors: Andreas Bolte, Lutz Hilbrig, Britt Maria Grundmann, Andreas RoloffAbstract:& Context It is assumed that climate change will favour European Beech (Fagus sylvatica L.) to Norway spruce (Picea abies [L.] Karst.) at its northern range margins due to climate change and induced disturbance events. & Aims An old-growth mixed forest of spruce and Beech, situated near the northern Beech margin, was studied to reveal effects of disturbances and response processes on natural forest dynamics, focussing on the understory. & Methods We carried out analyses on understory dynamics of Beech and spruce in relation to overstory release. This was done based on a sequence of stand and tree vitality inventories after a series of abiotic and biotic disturbances. & Results It became apparent that Beech (understory) has a larger adaptive capacity to disturbance impacts and oversto-ry release (68 % standing volume loss) than spruce. Understory dynamics can play a key role for forest succes-sion from spruce to Beech-dominated forests. Disturbances display an acceleration effect on forest succession in the face of climate change. & Conclusion Beech is poised strategically to replace spruce as the dominant tree species at the study area. Due to an increasing productivity and a lower risk of stand failure, Beech may raise into the focus of forestry in southern Sweden.
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the north eastern distribution range of european Beech a review
Forestry, 2007Co-Authors: Andreas Bolte, Tomasz Czajkowski, Thomas KompaAbstract:Today, European Beech (Fagus sylvatica L.) seems to be a markedly successful tree species in the north-east of its distribution range. The distribution area may be larger than originally assumed; past forest management is probably the main cause of the contraction in the postglacial European Beech range. Numerous attempts consistently have failed to locate a distinct distribution edge for European Beech. Therefore, we define northern and eastern Poland and the southern regions of the Baltic States as margins of European Beech distribution. Ecophysiological approaches have identified the drought constraints for European Beech in terms of (1) the critical limit for xylem cavitation and loss of hydraulic conductivity, reached at a shoot water potential of -1.9 MPa, and (2) a reduction in gross primary production and total ecosystem respiration when relative extractable soil water reaches 40 and 20 per cent, respectively. However, it is difficult to correlate European Beech distribution margins with single macro-climatic factors. Moreover, the adaptation of European Beech populations and provenances to drought and frost varies. The phenotypic plasticity and evolutionary adaptability of European Beech appear to be underestimated. These characteristics may counteract a further contraction of the European Beech range arising from climate change in the future.
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The north-eastern distribution range of European Beech—a review
Forestry, 2007Co-Authors: Andreas Bolte, Tomasz Czajkowski, Thomas KompaAbstract:Summary Today, European Beech ( Fagus sylvatica L.) seems to be a markedly successful tree species in the north-east of its distribution range. The distribution area may be larger than originally assumed; past forest management is probably the main cause of the contraction in the postglacial European Beech range. Numerous attempts consistently have failed to locate a distinct distribution edge for European Beech. Therefore, we defi ne northern and eastern Poland and the southern regions of the Baltic States as margins of European Beech distribution. Ecophysiological approaches have identifi ed the drought constraints for European Beech in terms of (1) the critical limit for xylem cavitation and loss of hydraulic conductivity, reached at a shoot water potential of – 1.9 MPa, and (2) a reduction in gross primary production and total ecosystem respiration when relative extractable soil water reaches 40 and 20 per cent, respectively. However, it is diffi cult to correlate European Beech distribution margins with single macro-climatic factors. Moreover, the adaptation of European Beech populations and provenances to drought and frost varies. The phenotypic plasticity and evolutionary adaptability of European Beech appear to be underestimated. These characteristics may counteract a further contraction of the European Beech range arising from climate change in the future.
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interspecific competition impacts on the morphology and distribution of fine roots in european Beech fagus sylvatica l and norway spruce picea abies l karst
European Journal of Forest Research, 2006Co-Authors: Andreas Bolte, I VillanuevaAbstract:Morphology and vertical distribution patterns of spruce and Beech live fine roots (diameter ≤2 mm) were studied using a soil core method in three comparable mature stands in the Solling: (1) pure Beech, (2) pure spruce and (3) mixed spruce–Beech. This study was aimed at determining the effects of interspecific competition on fine root structure and spatial fine root distribution of both species. A vertical stratification of Beech and spruce fine root systems was found in the mixed stand due to a shift in Beech fine roots from upper to lower soil layers. Moreover, compared to pure Beech, a significantly higher specific root length (SRL, P 0.10; SSA 225/212 cm2 g−1, P>0.10). Symmetric competition belowground between mixed Beech and spruce was observed since live fine roots of both species were under-represented compared to pure stand. However, the higher space sequestration efficiency suggests a higher competitive ability of Beech belowground.
Ralf Petercord - One of the best experts on this subject based on the ideXlab platform.
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Vitality loss of European Beech (Fagus sylvatica L.) and infestation by the European Beech splendour beetle (Agrilus viridis L., Buprestidae, Coleoptera)
Forest Ecology and Management, 2019Co-Authors: Claus Brück-dyckhoff, Ralf Petercord, Reinhard SchopfAbstract:Abstract Despite its dominance in Central Europe, Beech cultivation is not without risks, because drought periods and direct solar radiation of the stem are suspected of causing branch dieback, sunburn and predisposition to attack by the European Beech splendour beetle Agrilus viridis. Outbreaks of this beetle occurred in Germany in the early 1950s and in Hungary between 2003 and 2006 following severe precipitation deficiencies and extraordinary high temperatures. Leaf loss and an unusual accumulation of dead branches at the top of the crown of Beech trees prompted us to initiate in 2010 a three-year study to investigate whether and to what extent A. viridis infestations are involved in this damage pattern. In eight differently damaged Beech stands in Bavaria (south-eastern Germany) we measured the prevalence of A. viridis with flight interception traps in relation to the vitality status of Beech, checked the oviposition behaviour of females on trap trees, and investigated the infestation frequency of Beech trees depending on stand structure. The prevalence of A. viridis was significantly enhanced in sample plots with more heavily damaged Beech trees. At lying trap trees, females preferred parts of the bark for oviposition which had been exposed to south or west when the trees had been standing. Particularly, trees in open stands, distant to neighbours in the south and west as well as damaged by sunburn are predisposed to attack by A. viridis. It was proved that survival of A. viridis occurred in branches at the top of live Beech trees from where outbreak situations may be initiated due to climatic conditions like drought and/or extreme temperatures. Prevention of A. viridis infestation consists of avoiding sudden exposure to intense solar radiation of the Beech trunk by silvicultural measures.
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Genetic diversity and bark physiology of the European Beech (Fagus sylvatica): a coevolutionary relationship with the Beech scale (Cryptococcus fagisuga).
Tree physiology, 2000Co-Authors: Doris Krabel, Ralf PetercordAbstract:In 1994 and 1995, the degree of infestation by the Beech scale (Cryptococcus fagisuga Lind.) was recorded on 120 Beech trees (Fagus sylvatica L.) in the Pless Forest near Gottingen, Germany. Simultaneously, the trees were characterized genetically and compounds of primary and secondary metabolism of Beech bark were analyzed. A correlation was established between Beech scale infestation and the genotype of the host trees, based on gene locus A of isocitrate dehydrogenase (IDH-A). The fraction of infested Beech trees was higher in the heterozygous genotype A2A3 group than in the homozygous genotype A2A2 and A3A3 groups, whereas the fraction of Beech trees with decreasing infestation from one year to the next was lower in the heterozygous genotype A2A3 group than in the homozygous genotype A2A2 and A3A3 groups. Concentrations of soluble carbohydrates, protein amino acids and proanthocyanidins were determined in the inner and outer bark of trees with differing degrees of infestation. The results indicate that the defense reaction of Beech against infestation by Beech scale comprises multiple processes in which nutrient availability to the Beech scale is reduced by concentration shifts and by the formation of inhibiting compounds.
