Fagus Silvatica Research Articles

Release of mutagens after chemical or microbial degradation of beech wood lignin

The microbial or chemical degradation of lignin from untreated samples of beech wood dusts ( Fagus silvatica) resulted in the release of different mutagenic responses in the Salmonella/mammalian plate incorporation assay. In the first experiment using chemical degradation of lignin, dust samples were pre-extracted using acetone-water; the lignin portions were degraded into simpler compounds which were further fractionated on a Sephadex-LH20 column. The compounds isolated from the second phase of Sephadex, representing substances with a 3–4 ring structure and/or those of the same molecular weight, were highly mutagenic towards Salmonella typhimurium TA100 in the presence of metabolic activation. These substances were also active to some extent in strain TA 1537 both in the presence and absence of Aroclor-induced rat liver homogenates. In contrast, no direct- or indirect-acting mutagenicity was found when testing with strains TA97 and TA98. Strain TA1535 responded positively only to direct-acting mutagens in the fraction tested. The mutagenic fraction was found to be toxic to the cells when tested in a histidine-rich medium. Repurification of this mutagenic fraction, using silica-gel column chromatography, revealed much higher mutagenic activity than the test material towards strain TA100. In the second pilot experiment, Phanerochaete chrysosporium and Chaetomium globosum, which are known for their ability to degrade lignin, were each incubated with wood dusts in a mixture of physiological saline and nutrient broth for either 3 or 30 days. Significant mutagenic activity was observed with the dust extract after incubation with Ph. chrysosporium but not with Ch. globosum which is a known degrader of beech lignin. These results are discussed regarding hypotheses on the carcinogenicity of beech wood dusts.

General methods and materials

In the winter of 1982–83 an experiment was initiated at the University of Hohenheim to investigate the long-term effects of near ambient concentrations of O 3, SO 2, and simulated acidic rain and fog, alone and in combination, on mineral cycling, physiology, biochemistry and anatomy of Norway spruce ( Picea abies L. Karst.), Silver fir ( Abies alba Mill.) and European beech ( Fagus silvatica L.) seedlings in model ecosystems. Open-top chambers above soil lysimeters were protected with shelters 1 m above the open-top against intrusion of ambient dust and rain. The soil, a replaced acid brown earth with a base saturation of 20–30% was from the Black Forest region of the Federal Republic of Germany. This paper describes the technical design aspects of the study, including chamber construction and ventilation, SO 2 and O 3 application and monitoring, simulated precipitation forms and dispensing features, and the environmental parameters monitored. A short description of the plants used and the soil status is also presented. Chamber climatic and edaphic conditions allowed tree seedling normal growth over the five years of study. The pollutant levels within the appropriate chambers were comparable to ambient concentrations found at southwest German forest sites and varied with weather conditions.

Interactions betweenLaccaria laccata, Agrobacterium radiobacter and beech roots: Influence on P, K, Mg, and Fe mobilization from minerals and plant growth

Fagus silvatica L. inoculated or not with the ectomycorrhizal fungusLaccaria laccata and/or a phosphate-solubilizing rhizobacterium,Agrobacterium radiobacter, was cultivated in a greenhouse in lysimeter cylinders containing rock phosphate and a mica (phlogopite) as the only sources of P, Fe, Mg and Al. After two years, beech dry matter and P, Mg, Fe and K uptake were higher for plants inoculated—either withAgrobacterium radiobacter or withLaccaria laccata, but not for those plants inoculated with both micro-organisms—than for uninoculated plants. Mineral element mobilization from rock phosphate and from phlogopite was also greater when plants were inoculated with the bacteria or with the ectomycorrhizal fungi. Such mineral element dissolution can be related to the increased root growth but also to the amount of organic acids released in the rhizosphere. The absence of significant effects of dual inoculation suggested competition between micro-organisms.

Ultrastructure in leaves of Fagus silvatica and Carpinus betulus individuals tolerant and susceptible to SO 2 and heavy metal pollutants

The ultrastructure characteristics of leaves during the development of cell organelles, in the “greening process” of spring, have been studied in pollutant-tolerant and susceptible individuals of beech ( Fagus silvatica) and hornbeam ( Carpinus betulus) in an area polluted with SO 2 (the main pollutant may reach 0.06–2.72 mg/m 3), heavy metals, and other gases discharged by non-iron metal processing factories. Leaves from tolerant beech and hornbeam individuals did not undergo ultrastructural changes compared to control leaves in an unpolluted area. The susceptible and very susceptible individuals of both species gradually undergo modification in organelle ultrastructure not only during the first steps of greening and momentary exposure to air pollution, but also as a result of long-term exposure to chronic pollution in the forest.

Xylogénèse chez les Dicotylédones arborescentes. V. Formation du bois de tension et transport de l'acide indole acétique tritié chez le Hêtre

Upper stems of young beeches (Fagus silvatica L.) were bent into Jaccard loops in May. If they stayed on the tree, they produced a wide arc of extreme tension wood on the upper side of the loop, which contained numerous gelatinous fibers, few vessels, and little axial parenchyma. On the lower side of these loops, xylogenesis was nearly stopped. If bent stems were removed from the tree, xylogenesis was far less asymmetric: the wood formed on the upper side contained normal vessels and axial parenchyma, but also gelatinous fibers; on the lower side, the wood was normal. Transport and metabolism of 3H-labelled indole acetic acid was studied in both models. In intact loops left on the trees, lateral auxin transport took place mainly towards the lower half of the stem. In isolated loops, no preferential direction could be detected for lateral auxin transport. Extreme tension wood differentiation on the upper side of a bent stem requires the intervention of correlative factors, not only from buds, but also from the base of the tree, which particularly influence lateral downward transport of auxin.

Improvements in methods for determination of abscisic acid and indole-3-acetic acid by high-performance liquid chromatography

Improvements and simplifications in the early steps of the procedure for analysis of indole-3-acetic acid and abscisic acid by high-performance liquid chromatography (HPLC) are described. These include sample preparation, extraction and purification of the hormones. The method was applied to the leaves of Fagus silvatica and pines of Picea abies. With acetonitrile as extraction solvent, the hormones were recovered with high efficiency and the amounts of other substances were reduced. Partitioning of the extract between chloroform and water at different pH values obviates the need for laborious methods for prepurification of the material, simplifies the procedure and permits the use of an analytical column for further purification of the hormones by HPLC. Some terms used for characterization of the analysis are discussed.

Selective damage to tree-seedlings by bank voles (Clethrionomys glareolus).

(1) Small saplings of Tilia cordata, when planted in deciduous woodlands, are damaged or destroyed by rodents. (2) Experiments with captive animals show that the damage is identical with that caused by bank voles. (3) Bank voles are present at all sites where damage occurs. (4) Small saplings of Betula spp. established naturally in the sites are very rarely damaged. (5) Seedlings of Quercus spp. and Fagus silvatica are damaged or destroyed but small saplings suffer little or no damage attributable to voles. (6) Experiments with captive bank voles demonstrate marked differences between species of tree in their susceptibility to damage. (7) Tilia cordata is often severely damaged or destroyed. (8) Betula spp. suffer little or no damage. (9) Damage and destruction of small saplings is an important factor in the failure of regeneration of T. cordata in English woodlands because of the low density of seedlings and low frequency of large crops of fertile fruits.

Leaf aging and lipid peroxidation: The role of the antioxidants vitamin C and E

To study age‐related peroxidation in annual beech (Fagus silvatica Mill.) leaves and perennial fir (Abies alba Mill.) needles, the concentration changes of the antioxidants vitamin C (ascorbic acid) and vitamin E (α‐tocopherol) present in leaves and needles were determined, and the formation of thiobarbituric acid reactants was measured as an index of age‐related lipid peroxidation. With age, the content of the lipid‐soluble antioxidant vitamin E increased, and the increase was higher in beech leaves than in fir needles. A comparable age‐dependent increase of the vitamin C content was found neither in leaves nor in needles. The concentration ratio of the vitamin C to the vitamin E present in leaves and needles, which determines the potency of the anti oxidative system consisting of both vitamins, declined with age. This decline was directly related to a higher peroxidation of lipids. The extent of age‐related peroxidative damage of cells seems to be controlled by the potency of anti oxidative systems.

Ecological and Evolutionary Interactions between Reproduction of Beech Fagus silvatica and Seed Eating Animals

Patterns of beech seed production, seedling establishment, sapling densities, and sapling mortalities were studied in several forests dominated by different tree species. In a beech dominated forest, seed production and seedling establishment were negatively correlated in space. Seedlings became established mainly where there was least canopy coverage of mature beeches. Vertebrate seed predation was low in a year with an abundant seed crop but relatively higher in a year with a moderate crop. In the latter year predispersal insect seed predation was about 39%. I suggest that mast seeding in trees is more effective in reducing seed predation by insects than by vertebrates. Data in the literature support this prediction. The mortality rates of saplings and small trees of beech and oak were higher below mature trees of their own species than below trees of other species. In a spruce forest without mature oaks and beeches there was a high density and low mortality of saplings and small trees of the latter two species. Evidence suggests that the jay Garrulus glandarius had dug down the acorns and beech nuts. The jay appears to store beech mast only when no acorns are available. This situation occurred in the study area in 3 out of 13 years. The jay seems to be one of the species that could have dispersed the beech northwards during the Holocene.

Recherches pollenanalytiques sur l'histoire tardiglaciaire et holocene de la vegetation des Monts d'Aubrac (Massif Central, France)

Eleven diagrams from ten peat bogs or mires in the Aubrac Mounts are discussed; they are supported by 22 14C datings. The passage from the Würmian Pleniglacial to the oldest Dryas (marked by the now classic intercrossing of Pinus and Artemisia curves) is noted for the first time in the region. Precisions are presented on the Late Glacial vegetational dynamics, and a first date is obtained for Juniperus expansion during the Bølling (12,810 ± 250 B.P.). A woodless younger Dryas is evidenced for the first time in the region. In the Preboreal, a period during which no expansion of Pinus is noted, pollen grains from aquatic species of Rumex are recorded. The well-dated beginning of the unbroken Tilia curve proves to be younger than the beginning of the Atlantic. The Subboreal is characterized by Fagus dominance and the existence of local “landnams”. During the Subatlantic, after an early deforestation (prior to the Middle Ages), Calluna heath and meadows take the place of the beech wood. The modern expansion of Pinus after the agricultural peak leads us to deny to existence of a vegetation series with Fagus silvatica and Pinus silvestris in Aubrac.

Carbon relations and competition between woody species in a Central European hedgerow : I. Photosynthetic characteristics.

The CO2 uptake capacity of leaves of five competing woody species in an undisturbed developing Central European hedgerow was investigated for possible factors determining competitive ability in the field. Light-saturated maximal CO2 uptake (A max) showed species-specific seasonal variations in Prunus spinosa, a bushlike pioneer on fallow land, in Crataegusxmacrocarpa and Acer campestre, two treelike species dominating the canopy, in Rubus corylifolius, a pioneer liane, and in Ribes uva-crispa, a shrubby undergrowth species. In fully-expanded sun leaves of Prunus, Crataegus and Acer A max ranged from 8 to 12 μmol m-2 s-1 while it ranged from 6 to 15 μmol m-2 s-1 in Rubus and Ribes. The temperature responses showed no difference among species. Neither leaf photosynthetic capacity nor nutrient use of carbon fixation determined competitive ability. Differences between species in the capacity of leaves to adapt to shade resulted in differences in species' establishment in the understory and demonstrated the importance of growth in order to escape light-limiting conditions. A specific sequence of species was found for the range of A max in sun leaves. It was highest in an early pioneer of low competitive ability (Rubus), medium in a later pioneer (Prunus) and in successional plants (Crataegus, Acer), and lowest in the climax species of high competitive ability, Fagus silvatica, (3-4 μmol m-2 s-1; Schulze 1970).

Effects of air pollution on forest ecosystems and waters—the principles demonstrated at a case study in Central Europe

The concept of stress and strain is used as a framework to outline the natural stress acting on forest ecosystems. As a measure of the air pollution load to forest ecosystems the deposition rates of acids and heavy metals are dealt with for a beech ( Fagus silvatica) and a Norway spruce ( Picea abies) ecosystem in the Solling in Central Europe. As a measure of the long term carrying capacity of the ecosystems the input/output balance of acids, bases and heavy metals is used for the ecosystem as a whole and for its compartments. On the base of these data the risk for the forest ecosystems due to present level of air pollution is evaluated in general terms.

A simulation model of the water uptake of a beech forest: testing variations in root biomass and distribution

AbstractA validated mathematical model was used to simulate the effects of roots biomass and distribution on the water uptake of a 120‐year old beech (Fagus silvatica L.) stand located at Solling (West Germany).The modell was based on the soil‐water movement equation including an extraction term to account for the water uptake of the root system. This extraction term varies with the meteorological conditions, root density and soil water potential.Root biomass values considered were: 500 kg. ha−‐1, 1000 kg. ha−‐1, 2000 kg. ha−‐1, 4000kg. ha−‐1 and 6000 kg. ha−‐1. For each of these values, five different distributions were tested. These ranged between a soil profile 0.40m deep with high root concentration to a 1.00m soil profile with idealized uniform root distribution. The model was run under two different rainfall conditions: i) an uncommon dry year (1971), (ii) a hypothetical normal year without a dry period.The model showed the fundamental importance of the root distribution under the given meteorological conditions. This was more evident when the root biomass was low and medium. A good root distribution throughout the profile allowed the forest to overcome long dry periods. With the maximum root biomass value the distribution had no effect on the forest water uptake.

Optische Eigenschaften und Pigmente von Sonnen- und Schattenblättern der Rotbuche (Fagus silvatica L.) und der Blutbuche (Fagus silvatica cv. Atropunicea)

The spectral optical properties of sun- and shade-leaves of the beech ( Fagus silvatica L.) and the copper-beech ( Fagus silvatica cv. Atropunicea ) were determined for the wave range from 400 to 1350 nm. Measurements were taken during the main growing season (july-August). Also measured were the spectral irradiation outside and inside the crown. For the different leaf modifications the mean optical properties and the radiation energy input was calculated. The differencies between the values of the optical properties of all the measured leaf types are for the visible, the near infrared or the whole wave range of the global radiation less than 10 %. The great difference in the colouring of the sun-leaves of the copper-beech compared with the ordinary beech results only a 4 % higher absorption of global radiation energy. The radiation in the middle of the crown is not only the radiation transmitted through the leaf layers but also includes diffuse radiation inciding between the leaves or the leaf layers. The pigments and the flavonoids were extracted and the absorption spectrums and the amount of single pigments determined. The shade-leaves of the beech have about the same pigment and flavonoid content as the leaves of the copper-beech. The same is valid for the pigment content of the sun-leaves of both beech varieties. The anthocyanin content is not only very high for the sun-leaf of the copper-beech but there is also a considerable amount of flavonoids in the sun-leaves of the ordinary beech. Neither the optical properties nor the pigment and flavonoid relations or the radiation energy input give evidence of considerable differencies in the radiation ecology between the beech and its copper coloured mutant.

Fagus silvatica L. und das aceri-fagetum an der alpinen Waldgrenze in Mitteleurop�ischen gebirgen

In the Central Europaean mountain ranges, the alpine timberline is usually formed by Picea abies or by other conifers (Larix decidua, Pinus mugo, Pinus cembra). Unlike in the East Europaean mountains, the Balkan Peninsula, the Europaean Mediterranean and Les Vosges, Fagus silvatica occurs sporadically on the alpine timberline in this area where it forms very specific woods. This type of the alpine timberline is bound to the association Aceri-Fagetum (Bartsch 1940, Moor 1952). This association is found on the highest sites of the Fagion alliance in the subalpine vegetation zone. Within this zone, the association is bound to localities with heavy snowfall and a submaritime climat. It occupies larger areas in the Swiss Jura and in Les Vosges. In other Central Europaean mountains (the Alps, Schwarzwald, Krkonose etc.) it occus in isolated areas only. Many trunk deformations and bush forms are found with Fagus on a large scale in the snow impacted localities (steep slopes, periphery of corries, avalanche slopes etc.). Crawling and sliding snow causes these growth deformations in the Fagus seedlings since their first year. The general increase of the vegetative propagation is a remarkable and exceptional response of Fagus in adapting to these extreme growth conditions. Under alpine timberline conditions, the generative propagation is very limited. The vegetative shoots with adventitious root systems are formed mainly from branches layering in the humus. The typical monocormonal tree-form of Fagus from lower altitudes turns in this way into a polycormon. From an evolutionary point of view, it is a suitable substitution; but from the ecological viewpoint, however, it is a sturdy growth form. In its typical form, the polycormon is formed by a number of vegetative shoots, which may be deformed but are very elastic and resistent. The number of shoots in a polycormon varies from 3–5 below, and up to 40–50 at and above the timberline. They are formed by shoots of a number of filial successions. The decay of a polycormon results from decreasing vitality of single shoots or, very often, it is caused by the impact of snow and ice. Considering, however, the fact that single shoots have a sufficient adventitious root system and are thus physiologically independent, the dying of the other shoots does not mean a danger for the existence of the remaining part of the polycormon. The age of a polycormon as a whole is difficult to determine. Fagus polycormons can be considered as a typical growthform of the highest sites of the association Aceri-Fagetum. No other tree species is able to form close stands under these conditions. This phenomenon is of primary importance for the existence of this plant community. The unusual character of the structure and dynamics of the highest Aceri-Fagetum stands gives rise to a special type of the alpine timberline which should be understood not as a ‘line’ but as a transitional zone between the closed stands and the hon-wooded plant communities of the subalpine vegetation zone. The dynamic succession of the Fagus polycormons guarantees the stability of the Fagus stands forming the alpine timberline.

CHEMICAL CHANGES DUE TO ACID PRECIPITATION IN A LOESS-DERIVED SOIL IN CENTRAL EUROPE

ABSTRACTIn a stand of Fagus silvatica in the Solling highlands, Federal Republic of Germany, we followed the effect of acid precipitation on chemical soil state and the ion fluxes in the ecosystem between 1966 and 1979. As indicated by increasing aluminum concentration in the soil solution and an in

Influence of Chemical Composition, Addition of Raspberry Leaves, and Nitrogen Supply on Decomposition Rate and Dynamics of Nitrogen and Phosphorus in Beech Leaf Litter

Newly fallen beech Fagus silvatica L. leaves from three forests of contrasting vegetation type in southern Sweden were incubated in pots on an identical soil under laboratory conditions. During a 26-wk period at + 12'C weight loss rates were initially somewhat higher for leaves from the most fertile site, but by 18 wk the rates had become similar. There was an absolute accumulation of nitrogen in the leaf litter, which was accelerated by supplying the element in organic or inorganic form to the soil. Nitrogen in protein added under the litter layer, and both nitrogen and phosphorus of wild raspberry leaves mixed with it, was transferred into the decomposing litter, but gave no or only a slight increase in weight loss rate. The different responses suggested that the nitrogen availability to decomposer microbes in the litter, in combination with a low lignin content, resulted in increased decomposition rate. The initial nitrogen concentration seemed to influence weight loss only during the initial period of decomposition. Phosphorus was also transferred into litter, but was retained less efficiently than nitrogen, suggesting a non-limiting availability for decomposer activity. No accumulation in litter from nitrogen deposition in simulated rain could be noted, but a certain unexplained increased weight loss. Finally, the different factors which might regulate the turn-over rate of organic matter and plant nutrients in soils of different beech forest type are discussed.

Untersuchungen über Cytokinine parasitischer Herkunft III. Cytokinin-Aktivitäten bei Melampyrum und Lathraea sowie bei Blattgallen an Populus, Fagus und Quercus

Summary Using two biotests there could be shown the production of substances with cytokinin-activities in parasitic plants ( Melampyrum arvense; Lathraea squamaria ) and in leaves with galls induced by parasitic insects ( Pachypappa marsupialis KCH., Pemphigus spirothecae PASS. and P. bursarius L. on Populus nigra ssp. pyramidalis; Mikiola fagi HTG. and Hartigiola annulipes HTG. on Fagus silvatica; Cynips [Diplolepis] quercusfolii L. on Quercus petraea ). Purified extracts of the whole plants ( Melampyrum, Lathraea ) and gall-bearing as well as gall-less leaves were separated chromatographically. The highest cytokinin-activities tested by growth of tobacco-callus-tissue and by inhibition of chlorophyll decrease in Xanthium leaves could always be detected at a Rf of 0.6–0.7 exceptionally Populus , exhibiting cytokinin-activities at a Rf of 0.2 additionally. The importance of cytokinin concerning the host-paras it relation is discussed.

The Role of Forest Vegetation in the Biogeochemical Cycle of Heavy Metals

AbstractConcentration of the heavy metals Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb was measured in different compartments of vegetation and soil in a beech (Fagus silvatica) and a spruce (Picea abies) forest and the inventory of these elements was calculated. During a period of 3 years the heavy metal concentration in precipitation and soil water fluxes below tree root zone was determined and total element fluxes were calculated.Annual input from the atmosphere is small (≤30%) for the metals Cr, Mn, and Ni when compared to the amounts stored in the annual increment of biomass. The percentage is higher for Fe (40 to 60%). Uptake of these metals must be supplied partly by weathering of soil minerals. Accumulation of Cu in biomass is completely accounted for by atmospheric input. Total uptake of Co, Zn, Cd, and Pb into the cycling fraction (leaves, needles) and the noncycling fraction (wood) can be accounted for or is exceeded by atmospheric input. Air pollution from industry, home firing, and motor vehicles is the probable source.Biomass contained up to 27% of total Cd in the ecosystem, but only about 8% of Cu, 2 to 5% of Ni, Zn, and Mn, about 1% of Pb and Cr, and <0.3% of Fe and Co. Accumulation of Pb, Fe, and Co is very strong in the organic surface layer which contains up to 180 times the amount of metal reaching soil as annual litterfall, but only 3 times the amount of Mn, indicating a fast release of the metal by decomposition of organic matter.

CO-Produktion höherer Pflanzen an natürlichen Standorten

The CO production by higher plants has been studied by intensive in situ measurements on Pinus silvestris, Fagus silvatica, Quercus robur and Acer pseudoplatanus . The measurements were carried out during different seasons using test atmospheres with CO and CO 2 mixing ratios of 0-200 ppb for CO and 300-700 ppm for CO 2 , The measurements showed a light dependent CO production with maximum values of 16 X 10 -7 g/h · dm2 leaf area at a radiation flux of 8 X 10 5 erg/cm 2 · sec. The CO production is independent of the seasons and the CO and CO 2 mixing ratios of the test atmospheres. A CO uptake by plant was not observed. Assuming the mean CO production rate of 1.6 X 10 -7 g/h · dm 2 at a radiation flux of 0.5 X 105 erg/cm 2 · sec to be representative for global conditions the mean world-wide global CO-production by plants amounts to 0.7 X 10 14 g/year.