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1.
About 50 naturally occurring chemical elements were quantitatively determined by AAS, ICP/AES, ICP/MS and INAA in the main vegetation cover of the Forest Biosphere Reserve near Kalinin, USSR. The lichen Hypogymna physodes, which was studied and compared with other plant species, accumulates the elements Al, As, Br, Ce, Co, Dy, Eu, Fe, La, Lu, Pb, Pr, Sb, Sc, Sm, Th, Tm, V, Zn, and Zr. At the same time, a depletion of the alkaline elements Na, K, Rb, and Cs and the alkaline earth elements Mg and Ca is to be observed. Within the moss cover certain heavy metals are also accumulated by Polytrichum commune and the various Sphagnum species. As in Hypogymna physodes there is also a pronounced depletion of the alkaline earth metals Mg and Ca, but contrary to Hypogymna physodes there is a simultaneous accumulation of the alkaline metals K and Rb in Polytrichum commune and additionally of Na in the Sphagnum species. This is in agreement with studies showing different behaviour for the element potassium in Polytrichum formosum in the course of several vegetation periods. Potassium accumulation was found at the beginning of the vegetation period contrary to the dilution effect due to biomass supply. The depletion of Mg and Ca in all accumulator plants seems to be a direct consequence of heavy metal concentration since this phenomenon occurs irrespective of the site, as was shown by a comparison with data from a German forest ecosystem (Grasmoor near Osnabrück). Clear bioindication behaviour of Polytrichum commune, the various Sphagnum mosses and Hypogymna physodes was found for the elements Mn, Ni, Sn, Th, Cr, Mo, and S since the same accumulation and depletion behaviour was observed for all three plants as a function of site. These plant species could thus be used as bioindication cadasters in the sense of ARNDT. The higher shrub plants examined (Vaccinium vitis-idaea and Vaccinium myrtillus) show the already known accumulation of the elements Ba and Mn (up to 4000 mg/kg of Mn for Vaccinium myrtillus). In general the concentration ranges for many elements are more restricted in higher plants.  相似文献   

2.
B. Markert 《Plant Ecology》1991,95(2):127-135
To get a first impression of the degree of pollution in the Forest Biosphere Reserve 350 km northwest of Moscow, samples of Polytrichum commune and peat profiles were measured by ICP/MS after decomposition by high-pressure ashing. Comparing the results with data found in similar systems in Central Europe the Forest Biosphere Reserve can be described than medium-polluted by heavy metals. Pb shows lower values as in comparable systems in Germany, due to the fact of lower traffic density in Sowjetunion. The status of the nutritional elements Ca, Mg and K is in the same order of magnitude as found in German forest ecosystems.  相似文献   

3.
Contrasting strategies for UV-B screening in sub-Arctic dwarf shrubs   总被引:5,自引:1,他引:4  
The content and distribution of UV-absorbing phenolic compounds was investigated in leaves of three species of Vaccinium co-existing at a site in north Sweden. Vaccinium myrtillus L., Vaccinium vitis-idaea L., and Vaccinium uliginosum L. exhibit markedly different strategies, in terms of localization and content of leaf phenolics and in their responses to UV-B enhancement. Plants were exposed to either ambient radiation or to enhancement of UV-B corresponding to 15% (clear sky) depletion of stratospheric ozone for approximately 10 years prior to commencement of this study. Vaccinium myrtillus contained the highest concentration of methanol-extractable UV-B-absorbing compounds, which was elevated in plants exposed to enhanced UV-B. Fluorescence and confocal laser scanning microscopy showed that these compounds were distributed throughout the leaf, and were particularly concentrated in chlorophyll-containing cells. In V. vitis-idaea, most phenolic compounds were cell wall-bound and concentrated in the walls of the epidermis; this pool increased in response to UV-B enhancement. It is suggested that these two plants represent extreme forms of two divergent strategies for UV-B screening, the different responses possibly being related to leaf longevity in the two species. The response of V. uliginosum was intermediate between the other two, with high concentrations of cell wall-bound phenolics in the epidermis but with this pool decreasing, and the methanol-soluble pool tending to increase, after exposure to enhanced UV-B. One explanation for this response is that this plant is deciduous, like V. myrtillus, but has leaves that are structurally similar to those of V. vitis-idaea.  相似文献   

4.
The effect of N supply on plant growth and leaf demography of a deciduous and an evergreen Ericaceae was studied in relation to their internal cycling of N. Mature ramets of Vaccinium myrtillus (deciduous) and Vaccinium vitis-idaea (evergreen) were established in sand culture for 1 year with an adequate supply of a balanced nutrient solution. During one growing season, the plants were given two levels of N supply enriched with 15N and eight sequential destructive harvests were taken. Recovery of unlabelled N in the new shoot was used to determine the remobilization of N from storage. Initially, growth was unaffected by N supply. After May, High N enhanced growth for both species but the nature of their growth response differed. For both species, new shoot biomass and leaf number increased but root biomass production was affected for V. myrtillus only. Whole plant biomass production was similar for both species under High N, but was greater for V. vitis-idaea under Low N. The amount of N remobilized to support new shoot growth was similar for the two species and was independent of N current supply. N was remobilized predominantly from previous year leaves for V. vitis-idaea and from previous year stems and roots for V. myrtillus. The contribution of remobilization to new shoot N was similar for the two species, but depended on N supply. Remobilization was faster in V. myrtillus, but lasted longer in V. vitis-idaea. The results are discussed in relation to species growth in N-poor environments, focusing on the extent to which species-differences in the dynamic of N remobilization and growth may explain their adaptation to constant and/or changeable N supply.  相似文献   

5.
Gwynn-Jones  D.  Lee  J. A.  Callaghan  T. V. 《Plant Ecology》1997,128(1-2):243-249
An experiment is described which studies the effects of enhanced UV-B radiation (simulating a 15% reduction in the Ozone layer) and elevated atmospheric concentrations of CO2 (600 ppm) on the dwarf shrub layer of a sub-arctic forest heath ecosystem at Abisko, North Sweden. The experimental treatments were first applied in 1993, and have covered most of the snow-free season (late May to early September) 1993–1995. Effects of the treatments on the four dwarf shrub species have been recorded largely using non-destructive measures (Vaccinium uliginosum, Vaccinium myrtillus – deciduous species and Vaccinium vitis-idaea and Empetrum hermaphroditum – evergreen species). Effects of the treatments on stem growth and leaf thickness have so far been small, although CO2 treatments initially stimulated stem extension in Vaccinium myrtillus 1993 and depressed growth in V. vitis idaea in 1994 and E. hermaphroditum during 1995. UV-B treatments stimulated fruit production in V. myrtillus in both 1994 and 1995, but there was no effect on reproductive phenology. There were also marked effects of UV-B treatments on insect herbivory in the deciduous dwarf shrubs; with leaf area loss being greater than the control in the UV-B treatment in V. myrtillus and less in V. uliginosum. The results point to the possibility of important effects of the treatments on physiological and chemical processes within the plants. The ecological results of such effects may not be immediately apparent, but may be far reaching, pointing to the need for long-term in situ experimentation in predicting the effects of these global change variables.  相似文献   

6.
The aim of this study was to investigate plant frost hardiness responses to ultraviolet (UV) radiation, since the few results reported are largely contradictory. It was hypothesized that functional adaptation of life forms could explain these contradictions. Dwarf shrubs and tree seedlings, representing both evergreen and deciduous forms, were tested (Vaccinium vitis-idaea, Vaccinium myrtillus, Pinus sylvestris, Betula pubescens and its red form f. rubra). The research was performed in Sodankyl?, Northern Finland (67°N), with enhanced UV-B- and UV-A-radiation treatments between 2002 and 2009. Plant frost hardiness was determined using the freeze-induced electrolyte leakage method in early autumn, during the onset of the frost hardening process. Additional physiological variables (malondialdehyde, glutathione, total phenols, C and N contents) were analyzed in V. vitis-idaea to explain the possible responses. These variables did not respond significantly to UV-radiation treatments, but explained the frost hardiness well (r2 = 0.678). The main finding was that frost hardiness decreased in the evergreen shrub V. vitis-idaea, particularly with enhanced UV-A radiation. No significant responses were observed with the other plants. Therefore, this study does not support the idea that enhanced UV radiation could increase plant frost hardiness.  相似文献   

7.
Studies were conducted in 2001-2003 at Valdai National Park (Novgorod region) and at the Zvenigorod biological station of Moscow State University. The morphology of flowers, flowering dynamics and composition of insect visiting flowers of Ericaceae species: Andromeda polifolia, Chamaedaphne calyculata, Ledum palustre, Oxycoccus palustris, Vaccinium myrtillus, V. uliginosum, and V. vitis-idaea L. were studied. Some species of insects visiting flowers were excluded from the list of pollinators on the basis of observation on their behavior. L. palustre was visited mainly by flies where as other investigated species were visited mainly by bumblebees. In some cases bumblebees were the only visitors of the investigated plants. Mechanisms that protect flowers from flies and short-tongued solitary bees visits and ensure a best pollination by bumblebees are various among different species of Ericaceae. Efficiency of nectary protection also differs among different plant species and is defined by particularities of their habitats and flowering phenology. As far as all species of this family during the flowering are dominants in typical habitats, a competition for the pollination with species of other families in most cases is megligible. Flowering periods of V. vitis-idaea and V. myrtillus in forest ecosystems overlapped weakly. Moreover, V. myrtillus is pollinated mainly by bumblebee queens where as pollinators of V. vitis-idaea are bumblebee workers, solitary bees and horse flies. The other investigated plant species inhabit only oligotrophic peat bogs. Thery are pollinated by bumblebees but periods of flowering are not overlapped and consequently follow one after another. L. palustre and V. uliginosum flower simultaneosly but they are pollinated by different pollinators.  相似文献   

8.
对鼎湖山大气降水、季风常绿阔叶林林冠穿透水、土壤水(30cm和80cm深)以及溪水中某些沉积元素进行了系统连续的观测研究,从沉积元素的转移过程阐明了鼎湖山自然保护区和季风常绿阔叶林所承受的环境压力,通过分析沉积元素在这些水文学过程中的浓度变化和相互联系,试图揭示该生态系统相应功能过程变化的规律。得到如下结果:(1)大气降水中的Pb含量远远高于穿透水、土壤水(30cm和80cm深)以及溪水中的含量,随着水分由输入向输出流动,Pb的浓度逐渐降低;(2)在大气降水、林冠穿透水、土壤水(30cm和80cm深)以及溪水中,Al离子的浓度逐步增加;(3)除Pb外,所有其他元素(Al、Mn、sr、Mg、Na、K和Ca)在土壤溶液中的浓度都高于5个水文过程的平均值;(4)Mn、K、Ca的输入和输出的浓度都不高;(5)Na和Mg在土壤水和溪水中的浓度超过5个水文过程的平均值。这表明:(1)鼎湖山的大气具有高浓度的Pb含量,而且Pb在季风常绿阔叶林系统中处于一个持续的积累过程;(2)酸性降水不仅活化了土壤中的Al元素,对各个水文学过程中的离子浓度也有增大的作用;(3)Na和Mg在当前的大气环境下有可能加速地从季风常绿阔叶林生态系统中淋洗出来。总之,由于酸雨和大气污染的影响,鼎湖山森林生态系统将处于不稳定状态。  相似文献   

9.
P. S. Karlsson 《Ecography》1987,10(2):114-119
The relationship between micro-site nitrogen status (total soil N conc., total vegetation N, and leaf N conc.) and performance (biomass) for two evergreen and two deciduous dwarf shrubs was studied in a subarctic heath. One deciduous species, Vaccinium uliginosum , dominated on sites having the highest vegetation nitrogen content and highest leaf nitrogen concentrations. The evergreen Empetrum hermaphroditum dominated on sites with a low total vegetation nitrogen content and low leaf nitrogen concentrations. Two other species, V. myrtillus (deciduous) and V. vitis-idaea (evergreen), showed intermediate patterns that were not clearly separated from either V. uliginosum or Empetrum . Soil nitrogen content showed no significant differences between micro-sites. Possible physiological reasons for the observed patterns are discussed.  相似文献   

10.
  • 1 . In 30 Hochmooren der Bundesrepublik Deutschland werden verschiedene Arten des Sphagnetum magellanici auf ihren Gehalt an Pb, Cd, Cu, Zn und Mn untersucht (Sphagnum magellanicum, Sphagnum rubellum, Polytrichum strictum, Vaccinium oxycoccus).
  • 2 . Während die Sphagnen besonders viel Pb anreichern, zeigt Polytrichum strictum hohe Cu-Gehalte. In Vaccinium oxycoccus treten sehr hohe Mn-Konzentrationen auf.
  • 3 . Von Vaccinium oxycoccus werden Blättchen, Sprosse und Wurzeln getrennt untersucht. Pb, Cd, Cu und Zn reichern sich besonders in den Wurzeln an, Mn dagegen in den Blättchen.
  • 4 . Es werden darüber hinaus vertikale Torfprofile auf ihr Schwermetallverteilungsmuster untersucht. Während sich vor allem Pb und Cd, aber auch Cu und Zn in den unteren Moosabschnitten und in den anschließenden Torfschichten anreichern, ist die Mn-Konzentration an der Polsteroberfläche am höchsten.
  • 5 . In der Schwermetallbelastung der Hochmoore treten deutliche regionale Unterschiede auf. Die höchste Pb-Belastung findet sich in den Hochmooren des Harzes, während die Pb-Belastung in NW-Deutschland, im südlichen Schwarzwald und im westlichen Alpenvorland am geringsten ist.
  • 6 . Beim Schwermetallgehalt in Sphagnum magellanicum bestehen zwischen Pb einerseits und Cd, Cu und Zn andererseits signifikante Korrelationen. Eine Sonderstellung unter den gemessenen Mikronährstoffen nimmt Mn ein.
  • 7 . Die Jahresnettoproduktion von Sphagnum magellanicum wird mit verschiedenen Methoden bestimmt. Sie beträgt im Mittel 3,0 g. dm?2 a?. Daraus lassen sich Immissionsraten für die einzelnen Schwermetalle berechnen, die für Cd und Zn rund die Hälfte der Emission dieser Metalle betragen.
Die Arbeit wurde durch die Deutsche Forschungsgemeinschaft gefördert, der wir an dieser Stelle besonders danken.  相似文献   

11.
红豆越桔活性成分研究及开发利用   总被引:1,自引:0,他引:1  
红豆越桔是一种新兴的水果,其果实根茎叶中含有丰富的活性物质——花青素、黄酮、有机酸等。这些活性物质具有抗氧化损伤、清除氧自由基、抑制癌细胞、提高视力等多种作用。本文综述了国内外近年来对红豆越桔活性物质的研究概况,以及对红豆越桔产品的开发现状,并对进一步的研究提出了展望。  相似文献   

12.
Studied contents of macro-, microelements and long-lived radionuclides in the following medicinal plants belonging to the wetland community of Siberian region, Russia: Sphagnum fuscum (Schimp.) Klinggr., Sphagnum balticum (Russ.) Russ. ex С. Jens., Polytrichum strictum Brid., Pinus sylvestris L., Pinus sibirica Du Tour, Betula pubescens Ehrh., Andromeda polifolia L., Ledum palustre L., Oxycoccus palustris Pers., Rubus chamaemorus L., Vaccinium uliginosum L., Comarum palustre L., Chamaedaphne calyculata (L.) Moench. Samples were collected in the sphagnum wetlands of Tomsk region and Khanty-Mansi Autonomous Okrug. For the purpose of research, we used roots, shoots and bark of the plants in the Pinophyta and Magnoliophyta species and turf of the Bryophyta species. The content of macro-, microelements in the plants was determined by an atomic emission spectrometer with inductively coupled plasma “iCAP 6300 Duo” of the “Thermo Scientific” company. The specific activities of the long-lived radionuclides Th-232, K-40, Ra-226, Cs-137 were measured by a gamma-ray spectrometric complex with a high purity germanium semiconductor detector by “ORTEC” (AMETEK) and a digital analyser “ORTEC DSPEC LF”. The obtained results of the element content are useful when selecting a medicinal plant species (or part thereof) which may be used in preparation of new medicinal drugs.  相似文献   

13.
Ericaceous dwarf shrubs including Calluna vulgaris and Vaccinium spp. occur both in open heathland communities and in forest ecosystems as understory vegetation. Ericaceous shrubs were once thought to form ericoid mycorrhizal associations with a relatively narrow range of ascomycetous fungi closely related to, and including, Rhizoscyphus ericae. However, perceptions have recently changed since the realization that a broader range of ascomycete fungi, and in some cases basidiomycete fungi, can also form associations with the roots of ericaceous plants. We used a combination of molecular approaches, including denaturing gradient gel electrophoresis, terminal restriction fragment length polymorphism, cloning and sequencing, to investigate the diversity of fungi associated with C. vulgaris roots collected across a heathland/native Scots pine forest vegetation gradient. We also determined differences in fungal community composition between roots of co-occurring C. vulgaris and Vaccinium myrtillus in the forest understory. Collectively, the data show that a large diversity of potentially ericoid mycorrhizal fungal taxa associate with roots of C. vulgaris and V. myrtillus, and that ascomycetes were about 2.5 times more frequent than basidiomycetes. The assemblages of fungi associated with C. vulgaris and V. myrtillus were different. In addition, the community of fungi associated with C. vulgaris hair roots was different for samples collected from the forest, open heathland and a transition zone between the two. This separation was partly, but not entirely, due to the occurrence of typical ectomycorrhizal basidiomycetes associated with the hair roots of C. vulgaris in the forest understory. These data demonstrate that forest understory ericaceous shrubs associate with a diverse range of ascomycete and basidiomycete taxa, including typical ectomycorrhizal basidiomycetes.  相似文献   

14.
采用高效液相色谱法对越桔果渣中黄酮甙元进行定性和定量分析.用甲醇和水(60:40)以0.8 mL/min流速进行洗脱,368 nm波长检测越桔果渣水解液中黄酮类成分并测定其含量.结果:越桔果渣中黄酮甙元主要有杨梅素和槲皮素,其含量分别为:0.0206%和0.0686%.该方法测定样品简单易行,分离效果佳,灵敏度高,重现性好,结果准确可靠.  相似文献   

15.
通过构建pVB4215植物双元表达载体,采用农杆菌介导法转化烟草,研究VviDREB1在植物体中的异源表达特性.结果显示,实验获得了25个Hyg抗性株系,经过PCR、RT-PCR和GUS组织化学染色检测及Hyg基因的PCR复检等多点验证,证实表达载体边界内序列完整地整合到2个烟草株系的基因组中.转基因烟草株系在4℃低温处理20 h后,恢复生长5 h,叶片光系统PSⅡ抗寒性分析结果表明,转基因植株的叶片快速叶绿素荧光曲线OJIP各点数值高于对照植株,VviDREB1基因能够显著提高烟草的荧光产量,最大光化学效率Fv/Fm和以吸收光能为基础的性能指数PIABS较对照高,说明VviDREB1对保护植物组织细胞内光合系统PSⅡ有明显的作用,转VviDREB1基因烟草对低温有一定的忍耐能力.  相似文献   

16.
Fruit-eating behaviour of Red grouse was studied in the Grampians of Scotland from analyses of bird droppings for seeds and from direct observations of feeding birds. The commonest moorland species with edible fruits are blaeberry, Vaccinium myrtillus L., cowberry, Vaccinium vitis-idaea L., and crowberry, Empetrum nigrum L.
The fruit-frugivore interaction is not species specific, as grouse ate berries of all the fruiting species, but almost all individuals showed high fruit specificity for one type of fruit. Fruit selection is density-dependent and probably depends on the formation by grouse of a search specific image of the commonest fruit available in the feeding area. This is well known in polyphagous predator-prey interactions in animals but has not so far been reported in animal-plant feeding interactions.
We related fruit selection to both relative fruit abundance and plant cover. Some birds were feeding highly selectively on crowberries which were low in fruit abundance but had high relative cover. This indicated that the fruit resource had been large but had become depleted. Such birds would eventually lose their specific searching image and, following a short period of random search, would form new searching images.
The fruit cues and effect of density dependent selection on the evolution of fruiting behaviour was discussed.  相似文献   

17.
大兴安岭北部林区野果资源及保护利用   总被引:1,自引:0,他引:1  
调查了大兴安岭北部林区野生果树种质资源及其开发利用现状。记录到该地区野生肉果类10科,15属,29种。其中越桔和笃斯越桔是大兴安岭北部林区资源极其丰富的野果。蔷薇科有16种,为该地区野生果树的优势科。介绍了11种具有重要经济价值的野果。大兴安岭北部林区的野果资源已得到初步开发利用,越桔、笃斯越桔、山刺玫等数种野果已进入产业化阶段。提出了合理保护和利用对策。  相似文献   

18.
分布尼泊尔至台湾的少齿越桔组(越桔属)   总被引:1,自引:0,他引:1  
对越桔属Vaccinium中曾经被认为属于越桔组sect.Vitis-idoea的种或与之相关的76个运算上的分类单位进行数值分析,并记录了44个特片,解析如下:Vaccinium sect.Vitis-idoea应是局限于越桔V.vitis-idaca这个种而言;5个喜马拉雅的分类单位:V.nummularia,V.paucicrenatum,V.delavayi,V.retusum,V.moupinense,有2个表面上类似V.vitis-idaea的分类单位,运算上部是聚类在一起都被归入少齿越桔组scet.Aethopus.其余20个操作分类单位(OTU)包含10个分类单位,每个都十分特殊,但没有显著的片段的祥式可分辨。  相似文献   

19.
In natural forest, disturbance changes tree species composition which in turn affects soil properties. Two areas in the Central Forest State Biosphere Reserve, in the Russian Southern Taiga Zone, differed in the intensity of disturbance: Norway spruce was the dominant species at one site, while at the other spruce was mixed with broadleaves. The presence of broadleaves was due to large gaps in the canopy having been formed, which have triggered vegetation succession. At both sites, five plots were selected to evaluate how the presence of broadleaves influences the properties of the soils under spruce. Soil samples were taken close to spruce trees and the O, A and E horizons were analysed. A difference in the distribution of organic matter in the soil horizons was evident, with a higher concentration in the O and A horizons at the spruce dominated site, while a more homogeneous distribution was found under spruce at the site where broadleaves were abundant. The organic matter did not only differ in quantity, but also in quality as estimated by the C/N ratio, and therefore affected the CEC and element relative availability. No differences at the two sites were found for water-extractable and exchangeable elements, but the ratio between the exchangeable and the acid-extractable forms were different, suggesting a higher relative availability of the elements at the spruce dominated site, and thus potentially higher leaching. Both theoretical and empirical studies have suggested that podzolisation and accumulation of organic matter in the O horizon are related to stagnation of ecosystem processes and ecosystem decline. Our data suggest that the presence to windthrow sites and the inclusion of broadleaf species acts to slow or even reverse podzolisation even in spruce dominated sites.  相似文献   

20.
General regularities in the structure of the microbial communities of southern taiga soil ecosystems and taxonomic differences between the microbial communities of soils with different hydrothermal characteristics are discussed with reference to the main types of soils of the Central State Forest Biosphere Reserve.  相似文献   

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