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1.
Effects of site preparation, shelterwood density and planting depth on the survival and growth of planted beech and oak seedlings were studied. Experiments were performed in one oak and one beech stand in southern Sweden. Two areas with different densities of shelterwood and one clearcut were established in each stand. Growth, damage and survival of the planted seedlings were observed for three years. Soil water potential was recorded weekly and radiation and soil temperatures were recorded continuously during the growing seasons.Neither site preparation methods nor planting depth affected oak seedling growth, when planting was carried out on fresh clearcuts or in shelterwoods, while growth of beech seedlings was positively affected by mounding. Growth of oak seedlings was inhibited by the shelterwood treatments. In beech seedlings, growth was lowest in dense shelterwood, while there was no difference in growth between seedlings on the clearcut area and in the shelterwood of low density. Differences in growth may be explained by differences in radiation and soil water potential.When planting was carried out on a one-year-old clearcut, site preparation improved the subsequent growth of oak and beech seedlings. 相似文献
2.
Biological and other alternative control methods were tested against the woolly beech aphid (Phyllaphis fagi). Field applications of mineral oil to the egg stage reduced initial aphid population by 75%, but only when the eggs were exposed to oil close to the time of hatching. Earlier oil treatments had no effect. Bioassays with the insect pathogenic fungus Lecanicillium lecanii (Verticillium lecanii) in the commercial formulation Vertalec® were conducted using different dosages, i.e. 1 × 106 ml?1 (recommended dosage) and 2 × 107 ml?1. Both nymphs and adults were susceptible to fungal infection at both dosages. The existence of a dense wax-covering in adult P. fagi had no protective effect against fungal infection. In bioassays where leaves were treated with the recommended dosage of Vertalec, there was no difference in mortality measured after 14 days between adult P. fagi with an intact wax-layer and adult P. fagi where the wax-layer had been removed. In semi-field trials with two L. lecanii treatments at the recommended dosage, the aphid population was reduced. There was no enhanced effect with the addition of an additive to the fungal suspension or from covering the plants with a polypropylene cover. The results reveal potential alternative control methods against P. fagi populations. However, adequate control with L. lecanii probably requires several treatments as opposed to the two that were tested in the present experiment. Furthermore, efficiency may depend on summer temperatures and humidity. 相似文献
3.
Torsten W. Berger Erich Inselsbacher Franz Mutsch Michael Pfeffer 《Forest Ecology and Management》2009,258(11):2578-2592
Studies on the combined effects of beech–spruce mixtures are very rare. Hence, forest nutrition (soil, foliage) and nutrient fluxes via throughfall and soil solution were measured in adjacent stands of pure spruce, mixed spruce–beech and pure beech on three nutrient rich sites (Flysch) and three nutrient poor sites (Molasse) over a 2-year period. At low deposition rates (highest throughfall fluxes: 17 kg N ha−1 year−1 and 5 kg S ha−1 year−1) there was hardly any linkage between nutrient inputs and outputs. Element outputs were rather driven by internal N (mineralization, nitrification) and S (net mineralization of organic S compounds, desorption of historically deposited S) sources. Nitrate and sulfate seepage losses of spruce–beech mixtures were higher than expected from the corresponding single-species stands due to an unfavorable combination of spruce-similar soil solution concentrations coupled with beech-similar water fluxes on Flysch, while most processes on Molasse showed linear responses. Our data show that nutrient leaching through the soil is not simply a “wash through” but is mediated by a complex set of reactions within the plant–soil system. 相似文献
4.
Two-year-old seedlings ofPinus koraiensis, Pinus sylvestriformis andFraxinus mandshurica were treated in open-top chambers with elevated CO2 concentrations (700 μL·L−1, 500 μL·L−1) and ambient CO2 concentrations (350 μL·L−1) in Changbai Mountain from June to Sept. in 1999 and 2001. The net photosynthetic rate, dark respiration rate, ribulose-1,5-bisphosphate
carboxlase (RuBPcase) activity, and chlorophyll content were analyzed. The results indicated the RuBPcase activity of the
three species seedlings increased at elevated CO2 concentrations. The elevated CO2 concentrations stimulated the net photosynthetic rates of three tree species exceptP. sylvestriformis grown under 500 μL·L−1 CO2 concentration. The dark respiration rates ofP. koraiensis andP. sylvestriformis increased under concentration of 700 μL·L−1 CO2, out that ofF. mandshurica decreased under both concentrations 700 μL·L−1 and 500 μL·L−1 CO2. The seedlings ofF. mandshurica decreased in chlorophyll contents at elevated CO2 concentrations.
Foundation item: This paper was supported by the National Natural Science Foundation of China (No. 30070158). Knowledge Innovation Item of
Chinese Academy of Sciences (KZCX2-406) and “Hundred Scientists” Project of Chinese Academy of Sciences.
Biography: Zhou Yu-mei (1973-) Ph. Doctor, Assistant Research fellow Institute of Applied Ecology. Chinese Academy of Sciences. Shenyang
110016. P.R. China.
Responsible editor: Song Funan 相似文献
5.
Soil moisture content (0–90 cm depth) and nitrate-nitrogen (NO3-N) concentrations in soil solution (90 cm depth) were monitored after gap formation (diameter 15–18 m) in three Danish beech-dominated forests on nutrient-rich till soils. NO3-N drainage losses were estimated by the water balance model WATBAL for one of the sites. Two forests were non-intervention forests (semi-natural and unmanaged), the third was subject to nature-based management. The study was intended to assess the range of effects of gap formation in forests of low management intensity. In the unmanaged and the nature-based managed forest, soil solution was collected for 5 years and soil moisture measured in the fourth year after gap formation. Average NO3-N concentrations were significantly higher in the gaps (9.9 and 8.1 mg NO3-N l−1, respectively) than under closed canopy (0.2 mg l−1). In the semi-natural forest, measurements were carried out up to 29 months after gap formation. Average NO3-N concentrations in the gap were 19.3 mg NO3-N l−1. Gap formation alone did not account for this high level, as concentrations were high also under closed canopy (average 12.4 mg NO3-N l−1). However, the gap had significantly higher N concentrations when trees were in full leaf, and NO3-N drainage losses were significantly increased in the gap. No losses occurred under closed canopy in growing seasons. Soil moisture was close to field capacity in all three gaps, but decreased under closed canopy in growing seasons. In the semi-natural forest, advanced regeneration and lateral closure of the gap affected soil moisture levels in the gap in the last year of the study. 相似文献
6.
Changes in phosphorus (P) fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom (Cytisus scoparius L.) and ryegrass (Lolium multiflorum) in pots were studied 14 months after the application of triple superphosphate at the rates of 0, 50, and 100 μg·g−1, to determine the fate of fertiliser-derived P in the rhizosphere soils. Application of P fertiliser increased NaOH-Pi, NaOH-Po, and H2SO4-Pi concentrations in the soil, but decreased the residual-P concentration. The resin-Pi concentration, which is extremely low in this soil (1 to 3 μg·g−1), remained the same. The majority of the added fertiliser P was however recovered in the NaOH-Pi fraction (40%–49%). This is due to the high P fixation in this soil (92%). The second highest P recovery was in NaOH-Po fraction (7%–19%). Under P deficient condition or addition at the rate of 0 μg·g−1, the NaOH-Pi concentration in the radiata rhizosphere soil was lower than that in the bulk soil and broom and grass rhizosphere soils.
This may be due to higher oxalate production by the roots and mycorrhiza under P deficient conditions which released some
of the P fixed to the soils in the rhizosphere, which needs to be tested in future studies.
Foundation project: This work was supported by Centre for Sustainable Forest Management at Forest Research Institute, New
Zealand. 相似文献
7.
Karl-Heinz Häberle Angela J. Nunn Ilja M. Reiter Herbert Werner Werner Heller Günther Bahnweg Sebastian Gayler Cornelius Lütz Rainer Matyssek 《European Journal of Forest Research》2009,128(2):99-108
To prevent carbon (C) loss to consumers, trees need to defend their primary production. The tree-internal conflict in resource
allocation between growth and defence demands has been the subject of various hypotheses but still requires quantification.
A conceptual approach to approximating the C amount dispensable in favour of primary production at the expense of defence
is demonstrated which is based on nine defence-related metabolite groups. Quantification is exemplified at the level of sun
and shade leaves of adult Fagus sylvatica and Picea abies trees, two species contrasting in foliage type, under oxidative stress as induced by ozone exposure. The difference between
maximum and minimum metabolite levels sampled several times throughout four consecutive growing seasons were conceived as
dispensable between growth and defence-related metabolism and expressed in proportion of the mean annual gross primary production
(GPP) of the foliage. In both species, this proportion amounted to between 2 and 5% of GPP (on a molar C basis). Remaining
uncertainties are discussed as concerning functional overlap of substances between growth and defence-related metabolism,
estimated classification of metabolite turnover rates and “third-party” trade-offs across C demands. Given the complexity
of plant defence, simplification is needed for modelling allocation trade-offs in plants. The presented conceptual approach
meets this need in approximating C transfer capacities between competing physiological demands and in stimulating empirical
assessments towards mechanistic understanding.
This article belongs to the special issue: “Growth and defence of Norway spruce and European beech in pure and mixed stands”. 相似文献
8.
Masanobu Tabata Takashi Kato Masatoshi Ohkubo Yasuhisa Abe Shuichiro Yoshinaga 《Journal of Forest Research》2002,7(2):105-112
The rot ofChamaecyparis obtusa (hinoki) trees was studied in the northern part of Kagawa Prefecture, Japan. Among 158 hinoki examined, butt rot was found
in 28.6, 58.3, and 100% of trees in the 29, 30, and 34-year-old stands, respectively. All trees with butt rot, and 11 trees
without it had rotted roots. Thirteen hinoki were peeled byCervus nippon (sika deer) and all of them were infected with butt rot. The maximum height of rot in deer-damaged trees was 2.6 m from the
ground level, but was 1.9 m in undamaged trees. About eighty-two percent of rotted trees showed rotted areas of less than
40 cm2 on the cross section of stems at the ground level. White mycelia and black flecks sometimes appeared in the rotted wood.
Basidiocarps of polyporaceous fungus were often found on felled logs and rotted stumps of hinoki and identified asPerenniporia subacida. Basidiomycetous fungus was isolated frequently from rotted wood of roots and stems, and determined to beP. subacida by comparative study on cultural characteristics. An inoculation experiment and wood-decay test proved that the fungus was
the cause of the rot of hinoki. Few absorbing roots of living trees were found in the clayey subsurface soil of the high dry
bulk density and the less soil aeration. Some absorbing roots had root rot and the rot spread from the base of the absorbing
root to the central part of the woody root. This is the first report on the rot of hinoki caused byP. subacida in Japan. 相似文献
9.
Effect of collar insertion on soil respiration in a larch forest measured with a LI-6400 soil CO2 flux system 总被引:1,自引:0,他引:1
Wen Jie Wang Yuan Gang Zu Hui Mei Wang Takashi Hirano Kentaro Takagi Kaichiro Sasa Takayoshi Koike 《Journal of Forest Research》2005,10(1):57-60
Little information is available on the effect of root cutting by the collar pre-insertion technique on soil respiration. In this study, we found that soil respiration rates decreased with increasing depth of collar insertion in both the with live roots intact and with live roots severed treatments, but the rate of decrease was substantially higher in the former. The cutting of roots, especially fine roots, may be responsible for this result. 相似文献
10.
Hermann Rodenkirchen Axel Göttlein Alessandra R. Kozovits Rainer Matyssek Thorsten E. E. Grams 《European Journal of Forest Research》2009,128(2):117-128
Saplings of Fagus sylvatica and Picea abies were grown under conditions of intra and interspecific competition in a 2-year phytotron study under combinations of ambient
and elevated ozone (+O3 which is 2 × O3, but <150 nl l−1) as well as carbon dioxide concentrations (+CO2 which is amb. CO2 + 300 μl CO2 l−1) in a full factorial design. Saplings were analysed for various mineral nutrients in different plant organs as well as biomass
production and crown development. The study was based on the assumption that nutritional parameters important for growth and
competitiveness are affected by stress defence under limiting nutrient supply. The hypotheses tested were (1) that nutrient
uptake-related parameters (a) as well as efficiencies in nutrient use for above-ground competition (b) of beech rather than
spruce are impaired by the exposure to elevated O3 concentrations, (2) that the efficiency in nutrient uptake of spruce is enhanced by elevated CO2 concentrations in mixed culture, and (3) that the ability to occupy above-ground space at low nutrient cost is co-determinant
for the competitive success in mixed culture. Clear nitrogen deficiencies were indicated for both species during the 2-year
phytotron study, although foliar nitrogen-biomass relationships were not so close for spruce than for beech. O3 stress did not impair nutrient uptake-related parameters of beech; thus hypothesis (1a). was not supported. A negative effect
of elevated O3 (under amb. CO2) on the N and P based efficiencies in above-ground space occupation (i.e. lower crown volume per unit of N or P invested
in stems, limbs and foliage) of beech supported hypothesis (1b). It appeared that ozone stress triggered a nutrient demand
for stress defence and tolerance at the expense of above-ground competition (trade-off). Crown volume of beech under O3 stress was stabilized in monoculture by increased nutrient uptake. In general, the +CO2-treatment was able to counteract the impacts of 2 × O3. Elevated CO2 caused lower N and S concentrations in current-year foliage of both tree species, slightly higher macronutrient amounts in
the root biomass of spruce, but did not increase the efficiencies in nutrient uptake of spruce in mixed culture. Therefore
hypothesis (2) was not supported. At the end of the experiment spruce turned out to be the stronger competitor in mixed culture
as displayed by its higher total shoot biomass and crown volume. The amounts of macronutrients in the above-ground biomass
of spruce individuals in mixed culture distinctly exceeded those of beech, which had been strongly reduced by interspecific
competition. The superior competitiveness of spruce was related to higher N and P-based efficiencies in above-ground space
occupation as suggested in hypothesis (3).
This article belongs to the special issue “Growth and defence of Norway spruce and European beech in pure and mixed stands”. 相似文献
11.
Yumei Zhou Shijie Han Junqiang Zheng Lihua Xin Haisen Zhang 《Frontiers of Forestry in China》2008,3(2):131-138
The two main components of soil respiration, i.e., root/rhizosphere and microbial respiration, respond differently to elevated
atmospheric CO2 concentrations both in mechanism and sensitivity because they have different substrates derived from plant and soil organic
matter, respectively. To model the carbon cycle and predict the carbon source/sink of forest ecosystems, we must first understand
the relative contributions of root/rhizosphere and microbial respiration to total soil respiration under elevated CO2 concentrations. Root/rhizosphere and soil microbial respiration have been shown to increase, decrease and remain unchanged
under elevated CO2 concentrations. A significantly positive relationship between root biomass and root/rhizosphere respiration has been found.
Fine roots respond more strongly to elevated CO2 concentrations than coarse roots. Evidence suggests that soil microbial respiration is highly variable and uncertain under
elevated CO2 concentrations. Microbial biomass and activity are related or unrelated to rates of microbial respiration. Because substrate
availability drives microbial metabolism in soils, it is likely that much of the variability in microbial respiration results
from differences in the response of root growth to elevated CO2 concentrations and subsequent changes in substrate production. Biotic and abiotic factors affecting soil respiration were
found to affect both root/rhizosphere and microbial respiration.
__________
Translated from Journal of Plant Ecology, 2007, 31(3): 386–393 [译自: 植物生态学报] 相似文献
12.
To investigate the linkage types between carbohydrates and lignin, residual lignins were isolated from three different unbleached
pulps [kraft, alkaline sulfite anthraquinone methanol (ASAM), and soda with anthraquinone (AQ) and methanol] of spruce and
beech wood and then characterized by oxidation with 2,3-Dichloro-5,6-dicyanobenzoquinone and followed by Prehm’s methylation.
In residual lignins, sugar moieties were bound to lignins via benzyl ether bonds. In particular, galactose and mannose are
predominantly linked to lignin fragments in residual lignins of spruce wood, while xylose and galactose are favored in the
formation of LC bonds in the residual lignins of beech wood. In the case of hexoses, primary hydroxyl groups (C6 position)
preferentially take part in benzyl ether linkages. Hydroxyl groups in the C2 and C3 positions of xylose participate in LC
bonds and a small portion of arabinose was notably connected to lignin via the C5 position. Approximately seven or eight sugars
were connected in soda/AQ/methanol residual lignin per 100 C9 lignin units, while the frequencies of LC bonds in kraft and
ASAM residual lignins were distinctively less at one to three sugars per 100 C9 lignin units.
The publication of this article was made possible by an Emachu Research Fund. The authors are grateful for the fund. 相似文献
13.
The changes of Ca2+ levels in young leaf cells of bromegrass under different controlled chilling temperatures were inves- tigated by an antimonite precipitation cytochemical method. The main results were as follows: under 25/20℃ (day/night) tempera- ture and 14 h photoperiod, electron-dense Ca2+ antimonite precipitates, indicators of Ca2+ localization, were mainly localized in the vacuoles, cell walls and intercellular spaces; few Ca2+ deposits were observed in the cytosol and nuclei. After a 3℃ chilling treatment for 3 h, many Ca2+ precipitates appeared in the cytosol and nuclei, indicating that Ca2+ influx had occurred in the cytosol and nuclei. When the 3℃ treatment was prolonged to 8 h, more Ca2+ deposits appeared in the nuclei and cytosol, but the amount of Ca2+ deposits in both the cytosol and nuclei decreased markedly after a 24 h treatment and most Ca2+ deposits were returned to the vacuoles and intercellular spaces after an 8 d treatment. When bromegrass was exposed to 7℃ for 3 h, the Ca2+ distribution in the cells had no visible changes, compared with that of the 25/20℃ grown control plants. However, when the chilling treatment of 7℃ was prolonged to 8 h, a Ca2+ influx occurred, where many Ca2+ deposits were observed in the nuclei and cytosol. More Ca2+ deposits appeared in the nuclei and cytosol after a 24 h treatment, but the amount of Ca2+ deposits in the cytosol and nuclei was reduced markedly after an 8 d treatment. After a 14 d treatment, the remaining low level of Ca2+ was recovered in both the cytosol and nuclei and the Ca2+ deposits were again located in the vacuoles and the intercellular spaces. The dynamics of subcellular Ca2+ localization in young leaf cells of bromegrass during a 12℃ chilling treatment were similar to those of the 7℃ treatment. Besides, the results showed that the frost tolerance ofbromegrass exposed to 3℃ for 8 d increased by 6℃, for 7℃ and 8 d by 4℃ and for 12℃ and 14 d by 3℃, compared with the controls. 相似文献
14.
Quantity of litter fall, its chemical composition, nutrient addition and changes in chemical constituents of soil were studied
under agroforestry systems involving Populus deltoides and Eucalyptus hybrid tree with intercrops of Cymbopogon martinii Wats and Cymbopogon flexuosus Wats in the tarai tract of Kumaon hills of U.P. India. P. deltoides had significantly more diameter (63%) as compared to E. hybrid. There was decrease in herb (5.4%) and oil yield (15.4%) of grasses due to trees, but both the grasses did not affect the
performance of trees.
On an average, dry litter production of P. deltoides was 5.0 kg tree−1 year−1 where as of E. hybrid 1.5 kg tree−1 year−1. The litter of P. deltoides contained 1.3 times more N and 1.5 times P and K of E. hybrid. Addition of N, P and K through P. deltoides litter was 36.6, 91.6, and 69.9 per cent more than E. hybrid litter, respectively. Under these two canopies soil organic carbon was enhanced by 33.3 to 83.3 per cent, available N by
38.1 to 68.9 per cent, available P by 3.4 to 32.8 per cent and available K by 5.8 to 24.3 per cent over control (no tree canopy)
in 0—15cm layer. P. deltoides plantation was superior to E. hybrib in enriching the soil. 相似文献
15.
CO2 fluxes of a Scots pine forest growing in the warm and dry southern upper Rhine plain, SW Germany
The effects of the warm and dry weather in the southern upper Rhine plain in the southwest of Germany on the carbon balance of the Scots pine forest at the permanent forest meteorological experimental site Hartheim were analysed over a 14-month period. The investigation of the net ecosystem exchange of carbon dioxide (F
NEE) of the Scots pine forest started in the extraordinary hot and dry August 2003. Carbon dioxide fluxes were measured continuously using an eddy covariance system and analysed by use of the EDDYSOFT software package. After determining the temperature dependence of the forest ecosystem respiration and the daytime light dependence of the CO2 exchange, monthly and annual carbon balances of the Scots pine forest were calculated. Mean peak daytime F
NEE rates observed in August and September 2003 (−6.5±3.6 μmol m−2 s−1) were drastically lower than in August and September 2004 (−11.8±5.2 μmol m−2 s−1), which did not show pronounced deviations from the mean long-term (1978–2002) climatic conditions. In August 2003, the Hartheim Scots pine forest was a distinct CO2 source (35 g C m−2). The estimates of the annual carbon sink strength of the Scots pine forest ranged between −132 g C m−2 (August 2003–July 2004) and −211 g C m−2 (October 2003–September 2004). The main uncertainty in the determination of the carbon balance of the Hartheim Scots pine forest was introduced by the frequently low turbulence levels, i.e. the friction velocity corrected night-time F
NEE fluxes. 相似文献
16.
To elucidate the formation and chemical structures of water-soluble material in acid-soluble lignin (ASL), lignin aromatic nuclei model compounds of creosol (I) and 5-methoxycreosol (II) were reacted with xylose or xylan in the presence of apocynol as a counterpart for condensation in 72% sulfuric acid (SA). The reaction of I gave mainly condensation product. However, the condensation reaction of II with apocynol was suppressed because of steric hindrance from the methoxyl group, and II yielded a C-xyloside after refluxing in 3% SA together with condensation products. To obtain information on CHCl3-soluble material in ASL, model compounds of arylglycerol--aryl ethers with guaiacyl (VIII) and syringyl (X) nuclei were treated by the Klason procedure. VIII gave only insoluble polymerized product, while X gave insoluble polymerized product and CHCl3-soluble low molecular weight products, which were dissolved in 3% SA. These results prove earlier views that water-soluble material in ASL consists of condensation products formed from syringyl lignin and monosaccharide units in hemicellulose. In addition, the CHCl3-soluble material in ASL appears to be composed of low molecular weight degradation products from SA treatment of Klason lignin with the syringyl nucleus.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 and at the 47th Lignin Symposium, Fukuoka, October 2002, and was reviewed in Mokuzai Gakkaishi (2002) 48:55–62 相似文献