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Sample records for betula

  1. Essential Oil of Betula pendula Roth. Buds

    Directory of Open Access Journals (Sweden)

    Betül Demirci

    2004-01-01

    Full Text Available The essential oil of Betula pendula Roth. buds was obtained using both hydrodistillation and microdistillation techniques and their chemical compositions were analyzed using both gas chromatography (GC and gas chromatography–mass spectrometry (GC-MS. Overall, more than 50 compounds were identified representing 80% and 92% for hydrodistillation and microdistillation, respectively. The main components (by hydrodistillation and microdistillation, respectively found were α-copaene (12% and 10%, germacrene D (11% and 18% and δ-cadinene (11% and 15% in the analyzed essential oils. The microdistillation technique proved to be a useful tool and compliant alternative when compared to hydrodistillation.

  2. Essential Oil of Betula pendula Roth. Buds.

    Science.gov (United States)

    Demirci, Betül; Paper, Dietrich H; Demirci, Fatih; Can Başer, K Hüsnü; Franz, Gerhard

    2004-12-01

    The essential oil of Betula pendula Roth. buds was obtained using both hydrodistillation and microdistillation techniques and their chemical compositions were analyzed using both gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Overall, more than 50 compounds were identified representing 80% and 92% for hydrodistillation and microdistillation, respectively. The main components (by hydrodistillation and microdistillation, respectively) found were alpha-copaene (12% and 10%), germacrene D (11% and 18%) and delta-cadinene (11% and 15%) in the analyzed essential oils. The microdistillation technique proved to be a useful tool and compliant alternative when compared to hydrodistillation. PMID:15841263

  3. Individual variability of seeds radiosensitivity in two species of Betula

    International Nuclear Information System (INIS)

    Interspecific variability of the seed radiosensitivity of common birch (Betula verrucosa) and of while birch (Betula pubescens) have been studied experimentally. Seeds from different trees of both birch species differ considerably in sowing properties and in the response to γ radiation. Level of variability of seed germination and of seedlings ability to survive in the variant without radiation effect is lower for the common birch (Betula verrucosa). Presowing irradiation of seeds in dose of 40 krad causes the increase of the level of seed germination of commmon birch (Betula verrucosa) in 6 times and of white birch (Betula pubescens) in 2 times. No differences are found in dose dependence between two series of different-ploid birch according to averaged values of seed germination for each excerpt

  4. Twelve Elastic Constants of Betula platyphylla Suk.

    Institute of Scientific and Technical Information of China (English)

    Wang Liyu; Lu Zhenyou

    2004-01-01

    Wood elastic constants are needed to describe the elastic behaviors of wood and be taken as an important design parameter for wood-based composite materials and structural materials. This paper clarified the relationships between compliance coefficients and engineering elastic constants combined with orthotropic properties of wood, and twelve elastic constants of Betula platyphylla Suk. were measured by electrical strain gauges. Spreading the adhesive quantity cannot be excessive or too little when the strain flakes were glued. If excessive, the glue layer was too thick which would influence the strain flakes' performance, and if too little, glues plastered were not firm, which could not accurately transmit the strain. Wood as an orthotropic material, its modulus of elasticity and poisson's ratios are related by two formulas:μij /Ei =μji /Ej and μij 0.95) between the reciprocal of elastic modulus MOE-1 and the square of the ratio of depth to length (h/l)2, which indicate that shear modulus values measured were reliable by three point bending experiment.

  5. Parasitic fungi of the genera Betula and Salix

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    Iwona Adamska

    2012-12-01

    Full Text Available In the years 2001-2004, the occurrence of parasitic fungi of plants of the genera Betula and Salix growing in the Słowiński National Park was investigated. The plant species examined included B. pubescens, B. pendula, S. aurita, S. caprea, S. cinerea, S. fragilis, and S. repens. Plants of the genus Betula were affected by 9 species of parasiting fungi. In Poland, three of them (Microsphaera ornata var. europaea, Phyllactinia guttata, Melampsoridium betulinum occur commonly, five (Asteroma leptothyrioides, Discula betulina, Fusicladium betulae, Phyllosticta betulina, Septoria betulina are rare, and Septoria betulae-odoratae has not been recorded to date. Three species, Asteroma leptothyrioides, Fusicladium betulae, Phyllosticta betulina, were found on new plant hosts. Plants of the genus Salix were attacked by 8 species of parasiting fungi. Four of them (Melampsora allii-fragilis, M. caprearum, M. epitea, Uncinula adunca var. adunca are common in Poland, four (Marssonina salicicola, Phyllosticta salicicola, Septoria salicicola, Trimmatostroma betulinum rarely occur here. Uncinula adunca var. adunca, Marssonina salicicola, Phyllosticta salicicola, Septoria salicicola and Trimmatostroma betulinum were associated with the plant species not reported earlier to be their hosts.

  6. Chemical characteristics of surface colour of birch veneer (Betula pendula)

    OpenAIRE

    Yamamoto, Akio

    2015-01-01

    Julkaistu vain painettuna, saatavuus katso Bibid. Published only in printed form, availability see Bibid This thesis investigates the discoloration of veneer produced from silver birch (Betula pendula) logs by means of biochemical and chemical analyses on the veneer and sap obtained from wood which was soaked at varying temperatures (20-70 ˚C). Drastic colour development was confirmed from the sap squeezed from green birch wood. The results from biochemical tests on the sap by sodium dodec...

  7. Phytochemical Investigation, Isolation and Characterization of Betulin from Bark of Betula Utilis

    OpenAIRE

    Himanshu Joshi; Gyanendra Kumar Saxena; Vikas Singh; Ekta Arya; Rahul Pratap Singh

    2013-01-01

    Betula utilis is a hardy perennial plant of moderate size up to 20 M in height, forming the upper limit of forest vegetation. It inhabitates along the Himalayan range from Bhutan westwards, ascending to an altitude of 4200 M. The bark of Betula utilis contains sitosterol, betulin, betulic acid, oleanolic acid, acetyloleanolic acid, lupeol, lupenone, methyl betulonate, methyl betulate and a new triterpenoid karachic acid. The ethanolic extract of powdered drug of Betula utilis was prepared. Mo...

  8. Two new phenylbutanoids from inner bark of Betula pendula.

    Science.gov (United States)

    Liimatainen, Jaana; Sinkkonen, Jari; Karonen, Maarit; Pihlaja, Kalevi

    2008-02-01

    Two phenylbutanoids, 7-{3R-[(4-hydroxyphenyl)butyl] beta-glucopyranosid-O-6-yl} 4-O-beta-glucopyranosylvanillin and 3-beta-glucopyranosyloxy-1-(4-hydroxyphenyl)-butanone were isolated from an aqueous methanol extract of the inner bark of Betula pendula. Their structures were determined by NMR spectroscopy and mass spectrometry. The complete assignment of proton and carbon signals was achieved by 1D and 2D NMR experiments: selective 1D TOCSY, HSQC, HMBC and DQF-COSY. PMID:18098157

  9. Procyanidin xylosides from the bark of Betula pendula.

    Science.gov (United States)

    Liimatainen, Jaana; Karonen, Maarit; Sinkkonen, Jari

    2012-04-01

    A procyanidin dimer xyloside, catechin-(4α→8)-7-O-β-xylopyranosyl-catechin, was isolated from the inner bark of Betula pendula and its structure was determined using 1D and 2D NMR, CD and high-resolution ESIMS. Interestingly, the 7-O-β-xylopyranose unit was found to be present in the lower terminal unit of the dimer. In addition to this procyanidin dimer xyloside, an entire series of oligomeric and polymeric procyanidin xylosides was detected. Their structures were investigated by hydrophilic interaction HPLC-HRESIMS. Procyanidin glycosides are still rarely found in nature. PMID:22273040

  10. Transcriptomic Analysis of Phenotypic Changes in Birch (Betula platyphylla Autotetraploids

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    Gui-Feng Liu

    2012-10-01

    Full Text Available Plant breeders have focused much attention on polyploid trees because of their importance to forestry. To evaluate the impact of intraspecies genome duplication on the transcriptome, a series of Betula platyphylla autotetraploids and diploids were generated from four full-sib families. The phenotypes and transcriptomes of these autotetraploid individuals were compared with those of diploid trees. Autotetraploids were generally superior in breast-height diameter, volume, leaf, fruit and stoma and were generally inferior in height compared to diploids. Transcriptome data revealed numerous changes in gene expression attributable to autotetraploidization, which resulted in the upregulation of 7052 unigenes and the downregulation of 3658 unigenes. Pathway analysis revealed that the biosynthesis and signal transduction of indoleacetate (IAA and ethylene were altered after genome duplication, which may have contributed to phenotypic changes. These results shed light on variations in birch autotetraploidization and help identify important genes for the genetic engineering of birch trees.

  11. A New Monoterpene Glucoside from the Leaves of Betula platyphylla Suk.

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new monoterpene glucoside, (2E,6Z)-2,6-dimethyl-8-b-D-glucosyloxy-2,6-octadien- oic acid, was isolated from the leaves of Betula platyphylla Suk. The structure was established by spectroscopic data.

  12. Ecological variation of radiosensitivity in the seeds of Betula verrucosa

    International Nuclear Information System (INIS)

    A study was made on variation of radiosensitivity in the seeds of common birch (Betula verrucosa Ehrh). Investigations were carried on in three types of forest-whortleberry birch grove (the top of the hill), mountain cranberry (the middle part of the hill), mixed grass (the bottom of the hill). The seeds in each area were picked from 10 well fruit bearing trees (from the middle part of top). Air-dry seeds were irradiated by 137Cs gamma-rays with 10, 20, 4 krad doses at 138 r/min dose rate. The seeds were let germinate under conditions of natural lighting and room temperatures. Radiosensitivity was evaluated from seed germination and seeding survival, and radiosensitivity variability level - with the help of variation ratio. It was established that differences in radiosensitivity among trees of different types of forest for seed germination and seeding survival of common birch, were not revealed. Radiosensitivity variation, resulted from heterogeneity of ecological conditions in different areas, is lower, than the level of individual variability of this property inside each planting

  13. FLUCTUATING ASYMMETRY OF BETULA PENDULA LEAVES AS A BIOINDICATOR OF AEROTECHNOGENIC POLLUTION OF AGROLANDSCAPES

    OpenAIRE

    Lobkov, V.; Vetrova, J.

    2014-01-01

    The main goal of our research was to determine the variability model and fluctuating asymmetry indices of the metric signs of Betula pendula as a typical species which grow uniformly in the Orel region and Orel.The following problems were solved:to collect material in the planting of silver birch in two areas;to determine the parameters of Betula pendula leaf blade and the level of its asymmetry; to explore the basic statistical properties of the asymmetry parameters of the individual feature...

  14. Dynamics of Betula ermanni population in subalpine vegetation in Changbai Mountain, Northeast China

    Institute of Scientific and Technical Information of China (English)

    Zou Chunjing; Han Shijie; Wang Xiaochun

    1999-01-01

    Betula ermanni population was divided into three groups: the upper population (2 000~2 200 m), the middle population (1 700~2000 m), and the down population (1 400~1 700 m) in Changbai Mountain. The dynamics of Betula ermanni populations in subalpine vegetation are studied and the population life table,fecundity schedule, survival curves, age structure, and fecundity curves were established. The results showed that the middle population is obviously the transition from the upper population to the down population.

  15. Phytochemical Investigation, Isolation and Characterization of Betulin from Bark of Betula Utilis

    Directory of Open Access Journals (Sweden)

    Himanshu Joshi

    2013-05-01

    Full Text Available Betula utilis is a hardy perennial plant of moderate size up to 20 M in height, forming the upper limit of forest vegetation. It inhabitates along the Himalayan range from Bhutan westwards, ascending to an altitude of 4200 M. The bark of Betula utilis contains sitosterol, betulin, betulic acid, oleanolic acid, acetyloleanolic acid, lupeol, lupenone, methyl betulonate, methyl betulate and a new triterpenoid karachic acid. The ethanolic extract of powdered drug of Betula utilis was prepared. Most of the constituents were found to be present in the ethanolic extract. Thus it was concluded that constituents of Betula utilis bark are more soluble in polar solvents. The ethanolic extract showed the presence of alkaloids, carbohydrates, flavonoids, saponins and triterpenes. After identification of crude extract, the main work was to isolate the desired compound (betulin. So, fractionation of ethanolic extract was done by suspending it in water and then extracted it with n-hexane and dichloromethane. Betulin was isolated from dichloromethane fraction using column chromatography. Ethyl acetate and n-hexane in various ratios (1:10; 1:5; 1:3; 1:2 was used as eluent for separation of desired compound from the dichloromethane fraction. After isolation of desired compound, it was subjected to characterization. For characterization studies; melting range, TLC and spectroscopic techniques (UV, IR, Mass and NMR were utilized.

  16. The correlation of the maximum intensity of fluorescence with pigment characteristics of leaves of Betula pendula

    Science.gov (United States)

    Zavoruev, V. V.; Zavorueva, E. N.

    2015-11-01

    Using fluorimeter Junior PAM (Heinz Walz GmbH, Germany) the fluorescence parameters of leaves of Betula pendula are investigated. A linear dependence of the maximum fluorescence (Fm) of leaves from the ratio of total chlorophylls concentration to concentration of carotenoids is obtained. Such dependence is found for samples collected during the period of vegetation and for simultaneous selection of colored leaves.

  17. Spatiotemporal models for predicting high pollen concentration level of Corylus, Alnus, and Betula

    Science.gov (United States)

    Nowosad, Jakub

    2016-06-01

    Corylus, Alnus, and Betula trees are among the most important sources of allergic pollen in the temperate zone of the Northern Hemisphere and have a large impact on the quality of life and productivity of allergy sufferers. Therefore, it is important to predict high pollen concentrations, both in time and space. The aim of this study was to create and evaluate spatiotemporal models for predicting high Corylus, Alnus, and Betula pollen concentration levels, based on gridded meteorological data. Aerobiological monitoring was carried out in 11 cities in Poland and gathered, depending on the site, between 2 and 16 years of measurements. According to the first allergy symptoms during exposure, a high pollen count level was established for each taxon. An optimizing probability threshold technique was used for mitigation of the problem of imbalance in the pollen concentration levels. For each taxon, the model was built using a random forest method. The study revealed the possibility of moderately reliable prediction of Corylus and highly reliable prediction of Alnus and Betula high pollen concentration levels, using preprocessed gridded meteorological data. Cumulative growing degree days and potential evaporation proved to be two of the most important predictor variables in the models. The final models predicted not only for single locations but also for continuous areas. Furthermore, the proposed modeling framework could be used to predict high pollen concentrations of Corylus, Alnus, Betula, and other taxa, and in other countries.

  18. PLATYPHYLLIN A, A NOVEL COUMARONE FROM THE LEAVES OF BETULA PLATYPHYLLA SUK.

    Institute of Scientific and Technical Information of China (English)

    SU-JUAN WANG; YUE-HU PEI; HUI-MING HUA

    2001-01-01

    A novel coumarone, platyphyllin A (1), was isolated from the leaves of Betula platyphylla Suk..The structure elucidation was accomplished by the analysis of spectroscopic data. Compound 1 was identified as a new coumarone skeleton, which was first isolated from plants.

  19. Comparative Carbon and Water Relations of Betula nana and Poa pratensis in West Greenland

    Science.gov (United States)

    Cahoon, S. M. P.; Sullivan, P. F.; Welker, J. M.; Post, E.

    2014-12-01

    The expansion of woody shrubs throughout much of the Arctic in recent decades is a common observation in response to climate change. However, we lack a complete understanding of how woody shrubs differ physiologically from neighboring species and how these differences may confer competitive advantages to woody shrubs as the climate continues to change. At a site in West Greenland, we combined detailed leaf physiological measurements with stable isotope analysis of plant leaf material, xylem water and soil water to elucidate the processes governing seasonal carbon (C) gain in the two dominant plant species at our study site: Betula nana and Poa pratensis. We hypothesized that cooler, drier soils beneath the Betula canopy would result in greater drought sensitivity during times of high atmospheric demand (i.e. greater water vapor pressure deficit; VPD), which would manifest in reduced leaf carbon isotope discrimination (Δ13C), reduced stomatal conductance (gs) and a negative relationship between leaf Δ13C and Δ18O in accordance with the dual-isotope conceptual model. Data collected over two consecutive growing seasons, however, revealed greater drought sensitivity in Poa, which displayed a dramatic reduction in Amax and gs during periods of high VPD, along with reduced leaf Δ13C. Additionally, leaf Δ13C and Δ18O were negatively correlated in Poa, suggesting strong stomatal influence on Δ13C. Conversely, we found no relationship between leaf Δ13C and Δ18O in Betula, indicating that seasonal variation in Δ13C may have been driven primarily by changes in photosynthesis. Our results suggest that, although Poa maintains greater average leaf-level photosynthesis, this species is more susceptible to drought than Betula. Meanwhile, it may be that Betula employs a strategy to avoid drought stress and maintain steady, yet conservative, C gain. This strategy may enable growth to continue during warm and dry conditions, conferring a competitive advantage for Betula in

  20. CORRELATION OF CONTENT ASCORBIC ACID IN THE ASSIMILATION APPARATUS BETULA PENDULA ROTH. WITH AGENT BY PATHOLOGICAL

    OpenAIRE

    Михаил Эдуардович Баландайкин

    2014-01-01

    Features of influence of set of anthropogenic factors and phytopathologic state of tree Betula pendula on concentration of ascorbic acid in it assimilation apparatus are considered. By criterion of influence Inonotus obliquus (Pers.: Fr.) Pilat and to presence pollution adaptable ability of a plant to action stressful factors, and also possibility of development of the mechanisms which are responsible for inhibition of biosynthesis of ascorbic acid estimated. It is shown that from all analyse...

  1. Effects of artificial defoliation and simulated insect damage on the growth of Betula pendula saplings

    OpenAIRE

    Varnagiryte-Kabašinskiene I; Araminiene V; Stakenas V

    2016-01-01

    One-year-old silver birch (Betula pendula Roth) saplings were subjected to artificial insect damage and defoliations of varying intensities, and subsequent growth indexes, biomass allocation patterns and photosynthesis were monitored during a 60-day period. Seven treatments were conducted in which the leaves of saplings were perforated with three or six holes per each leaf, and damaged by clipping one-third of each leaf, or they received 25, 50 and 75% defoliations during a single growing sea...

  2. Isolation, Characterization and Anticancer Potential of Cytotoxic Triterpenes from Betula utilis Bark

    Science.gov (United States)

    Joshi, Pushpa; Pal, Mahesh; Meena, Baleshwar; Upreti, D. K.; Rana, T. S.; Datta, Dipak

    2016-01-01

    Betula utilis, also known as Himalayan silver birch has been used as a traditional medicine for many health ailments like inflammatation, HIV, renal and bladder disorders as well as many cancers from ages. Here, we performed bio-guided fractionation of Betula utilis Bark (BUB), in which it was extracted in methanol and fractionated with hexane, ethyl acetate, chloroform, n-butanol and water. All six fractions were evaluated for their in-vitro anticancer activity in nine different cancer cell lines and ethyl acetate fraction was found to be one of the most potent fractions in terms of inducing cytotoxic activity against various cancer cell lines. By utilizing column chromatography, six triterpenes namely betulin, betulinic acid, lupeol, ursolic acid (UA), oleanolic acid and β-amyrin have been isolated from the ethyl acetate extract of BUB and structures of these compounds were unraveled by spectroscopic methods. β-amyrin and UA were isolated for the first time from Betula utilis. Isolated triterpenes were tested for in-vitro cytotoxic activity against six different cancer cell lines where UA was found to be selective for breast cancer cells over non-tumorigenic breast epithelial cells (MCF 10A). Tumor cell selective apoptotic action of UA was mainly attributed due to the activation of extrinsic apoptosis pathway via up regulation of DR4, DR5 and PARP cleavage in MCF-7 cells over non-tumorigenic MCF-10A cells. Moreover, UA mediated intracellular ROS generation and mitochondrial membrane potential disruption also play a key role for its anti cancer effect. UA also inhibits breast cancer migration. Altogether, we discovered novel source of UA having potent tumor cell specific cytotoxic property, indicating its therapeutic potential against breast cancer. PMID:27453990

  3. CORRELATION OF CONTENT ASCORBIC ACID IN THE ASSIMILATION APPARATUS BETULA PENDULA ROTH. WITH AGENT BY PATHOLOGICAL

    Directory of Open Access Journals (Sweden)

    Михаил Эдуардович Баландайкин

    2014-09-01

    Full Text Available Features of influence of set of anthropogenic factors and phytopathologic state of tree Betula pendula on concentration of ascorbic acid in it assimilation apparatus are considered. By criterion of influence Inonotus obliquus (Pers.: Fr. Pilat and to presence pollution adaptable ability of a plant to action stressful factors, and also possibility of development of the mechanisms which are responsible for inhibition of biosynthesis of ascorbic acid estimated. It is shown that from all analysed in the yielded work abiotic and biotic factors most essentially the pathogenic factor affects change of concentration of ascorbic acid in sheet plates of trees concerning norm.

  4. Evolutionary dynamics of birch (Betula aetnensis Rafin coppices on the Mount Etna (Sicily

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    Bagnato S

    2014-04-01

    Full Text Available Evolutionary dynamics of birch (Betula aetnensis Rafin coppices on the Mount Etna (Sicily. The aim of this paper is to evaluate the dynamics of Etna birch stands (Betula aetnensis Rafin following the cessation of silvicultural activities in the Etna Regional Park (Sicily. We investigated forest structure, natural regeneration, vegetation and deadwood in different forest types. Our findings highlighted three different dynamics for birch populations: stable birch stands in the high mountain area which might represent an edapho-climax forest; progressive dynamic birch stands in the intermediate mountain area, showing a gradual depletion of birch and a concomitant replacement with monospecific stands (calabrian pine, beech, oaks or mixed ones (with birch; pure birch stands (typical that tend to be regressive - especially under stressful conditions - and to be replaced by xerophilous grasslands. Following the cessation of coppicing and with stand ageing, the stumps transformation into more homogeneous stand structures have been increasing. Within the context of protected areas the restoration of coppice selection system (with appropriate adaptations could help to maintain the traditional forest landscape, acting as a silvicultural technique with low environmental and landscape impact.

  5. Fungi and bacteria associated with the wet and brown wood in trunk of Betula pendula trees

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    Krystyna Przybył

    2014-02-01

    Full Text Available Bacteria and fungi were isolated from external and internal zone of brown and water saturated wood of trunk of Betula pendula trees aged 44-46. Quantitative and qualitative differences in the bacterial and fungal populations were found between both the zones. Populations of bacteria increased towards the internal sapwood, contrary to the fungi which more frequently colonised the external zone. The most common bacteria were Pseudomonas spp. (mainly P.fluorescens biovar I whereas Bacillus macerans, B. alvei and Erwinia heibicola were able to degrade the polygalacturonic acid and pectin gels. In case of the fungi population, the most common (more than 3% colonising the external zone were successively: Phialophora fastigiata, Trichoderma harzianum, Alternaria alternata, Mortierella isabellina, Cladosporium herbarum, T. viride, C. cladosporioides and Melanconium betulinum. In the community of fungi occurring in the internal zone, the most common (more than 6.5% were:Cladosporium herbarum, Phialophora lagerbergii and Ph.fastigiata.

  6. Biomonitoring Study of Air Pollution with Betula pendula Roth., from Plovdiv, Bulgaria

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    Slaveya T. Petrova

    2011-07-01

    Full Text Available The present study is a small part of a program for application the methods of passive and active biomonitoring with tree, herbaceous, moss and lichen species for assessment of the anthropogenic factor in urban conditions. All reported results here are preliminary. Betula pendula was studied as a possible biomonitor of air pollution in Plovdiv. Eight sampling sites in the urban roadside, city center and suburban areas were investigated. Chlorophyll content was determined as essential and sensitive physiological parameter. The concentrations of 26 micro and macroelements were analyzed by FAAS and ICPMS. Maximum for chlorophyll was found in the birch leaves from west part of the town, minimum – in these from north part. More significant variations were detected for Ni, Mn, B, Cr, Co, Fe, Bi, Cd, Al, Zn. Highest concentrations of 12 elements were found in the samples, collected from the central area of Plovdiv.

  7. Slow pyrolysis of birch (Betula) studied with GC/MS and GC/FTIR/FID

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, M.; Ingemarsson, A.; Pedersen, J.R.; Olsson, J.O. [Chalmers University of Technology, Goeteborg (Sweden). Dept. of Physical Chemistry

    1999-03-01

    Small samples of wood (15 - 150 mg) from 8 different species of birch (Betula) were pyrolysed at 550{sup o}C. The compounds produced from the pyrolysis were analysed using gas chromatographic (GC) methods: direct injection with GC/FTIR/FID and pre-concentration with GC/MS. A broad distribution of oxygenated organic compounds was formed: aldehydes, acids, ketones, substituted furans and methoxylated phenols. The chromatograms were very similar for all eight species, both with direct injection and pre-concentration. Compared to similar studies for pine and spruces significantly higher amounts were formed in the molecular range 60 - 130 amu. The conifers showed more peaks with a molecular weight above 200 amu. (author)

  8. Estudo químico de extratos de folhas de Betula celtiberica Rothm. & Vasc.

    OpenAIRE

    Serra, Ana Patrícia Abrantes

    2013-01-01

    O período de estágio final, inserido no Plano de Estudos do Mestrado em Ciências Farmacêuticas da Universidade da Beira Interior, permitiu desenvolver competências técnicas, clínicas e deontológicas necessárias ao exercício da profissão farmacêutica. O presente trabalho encontra-se dividido em duas componentes, sendo a primeira o projeto de investigação de mestrado intitulado “Estudo Químico de Extratos de folhas de Betula celtiberica Rothm. & Vasc.” e a segunda o Relatório de Estágio em F...

  9. Identification of genes differentially expressed in extraradical mycelium and ectomycorrhizal roots during Paxillus involutus-Betula pendula ectomycorrhizal symbiosis

    OpenAIRE

    MOREL,M; Jacob, C; Kohler, A.; Johansson, Tomas; Martin, Francis; Chalot, Michel; Brun, Annick

    2005-01-01

    The development of ectomycorrhizal symbiosis leads to drastic changes in gene expression in both partners. However, little is known about the spatial regulation of symbiosis-regulated genes. Using cDNA array profiling, we compared the levels of expression of fungal genes corresponding to approximately 1,200 expressed sequenced tags in the ectomycorrhizal root tips (ECM) and the connected extraradical mycelium (EM) for the Paxillus involutus-Betula pendula ectomycorrhizal association grown on ...

  10. Effects of reindeer on the re-establishment of Betula pubescens subsp. czerepanovii and Salix phylicifolia in a subarctic meadow

    OpenAIRE

    Michael den Herder; Pekka Niemelä

    2003-01-01

    The effect of reindeer browsing on the regeneration of Betula pubescens subsp. czerepanovii and Salix phylicifolia was studied in a subarctic meadow in Finnish Lapland. The aim of the study was to see whether tree recovery from seeds is possible under heavy reindeer-browsing pressure. After removal of the ground and field layer vegetation in 1986, two exclosures were established so that the effect of reindeer on the secondary succession, starting from seeds, could be studied. The size and the...

  11. Free Recall Episodic Memory Performance Predicts Dementia Ten Years prior to Clinical Diagnosis: Findings from the Betula Longitudinal Study

    OpenAIRE

    Boraxbekk, Carl-Johan; Lundquist, Anders; Nordin, Annelie; Nyberg, Lars; Nilsson, Lars-Göran; Adolfsson, Rolf

    2015-01-01

    Background/Aims: Early dementia diagnosis is a considerable challenge. The present study examined the predictive value of cognitive performance for a future clinical diagnosis of late-onset Alzheimer's disease or vascular dementia in a random population sample. Methods: Cognitive performance was retrospectively compared between three groups of participants from the Betula longitudinal cohort. Group 1 developed dementia 11-22 years after baseline testing (n = 111) and group 2 after 1-10 years ...

  12. Bioactivity-guided isolation of antioxidant triterpenoids from Betula platyphylla var. japonica bark.

    Science.gov (United States)

    Eom, Hee Jeong; Kang, Hee Rae; Kim, Ho Kyong; Jung, Eun Bee; Park, Hyun Bong; Kang, Ki Sung; Kim, Ki Hyun

    2016-06-01

    The bark of Betula platyphylla var. japonica (Betulaceae) has been used to treat pneumonia, choloplania, nephritis, and chronic bronchitis. This study aimed to investigate the bioactive chemical constituents of the bark of B. platyphylla var. japonica. A bioassay-guided fractionation and chemical investigation of the bark of B. platyphylla var. japonica resulted in the isolation and identification of a new lupane-type triterpene, 27-hydroxybetunolic acid (1), along with 18 known triterpenoids (2-19). The structure of the new compound (1) was elucidated on the basis of 1D and 2D NMR spectroscopic data analysis as well as HR-ESIMS. Among the known compounds, chilianthin B (17), chilianthin C (18), and chilianthin A (19) were triterpene-lignan esters, which are rarely found in nature. Compounds 4, 6, 7, 17, 18, and 19 showed significant antioxidant activities with IC50 values in the range 4.48-43.02μM in a DPPH radical-scavenging assay. However, no compound showed significant inhibition of acetylcholine esterase (AChE). Unfortunately, the new compound (1) exhibited no significance in both biological activities. This study strongly suggests that B. platyphylla var. japonica bark is a potential source of natural antioxidants for use in pharmaceuticals and functional foods. PMID:27060627

  13. Disappearing population of Betula humilis Schrk. on the Maliszewskie Lake, NE Poland

    Directory of Open Access Journals (Sweden)

    Chrzanowska Agnieszka

    2015-03-01

    Full Text Available Betula humilis Schrk. is an endangered glacial relict inhabiting wet meadows, natural and drained fens. One of its declining populations is located on the Maliszewskie Lake (the Wizna swamp, north-eastern Poland. The goal of the present study was to estimate the number of B. humilis individuals in this locality. In the Maliszewskie Lake population, 59 ramets, grouped into three clusters, were found. Twelve nuclear microsatellite loci were chosen to genotype 52 ramets. The analysis revealed that all the shoots within the single cluster had the same genotypes at the loci considered. This means that each cluster constituted one genetically distinct individual; thus, there were only three individuals of B. humilis in the studied population. The maintenance of the B. humilis population in the Maliszewskie Lake area requires urgent active protection involving removal of the shading vegetation. In fact, the entire Maliszewskie Lake is worthy of protection because of its hitherto unexplained origin and the occurrence of many endangered bird species.

  14. Identification of SSR loci in Betula luminifera using birch EST data

    Institute of Scientific and Technical Information of China (English)

    LU Yong-quan; LI Hai-ying; JIA Qing; HUANG Hua-hong; TONG Zai-kang

    2011-01-01

    Expressed sequence tags (ESTs) are generated from single-pass sequencing of randomly picked cDNA clones and can be used for development of simple sequence repeat (SSR) markers or microsatellites.However,EST databases have been developed for only a small number of species.This paper provides a case study of the utility of freely available birch EST reources for the development of markers necessary for the genetic analysis of Betula luminifera.Based on birch EST data,primers for 80 EST-SSR candidate loci were developed and tested in birch.Of these,59 EST-SSR loci yielded single,stable and clear PCR products.We then tested the utility of those 59 markers in B.luminifera.The results showed 28 (47.6%) yielded stable and clear PCR products for at least one B.luminifera genotype.In addition,this study describes a rapid and inexpensive alternative for the development of SSRs in species with scarce available sequence data.

  15. Effects of artificial defoliation and simulated insect damage on the growth of Betula pendula saplings

    Directory of Open Access Journals (Sweden)

    Varnagiryte-Kabašinskiene I

    2015-07-01

    Full Text Available One-year-old silver birch (Betula pendula Roth saplings were subjected to artificial insect damage and defoliations of varying intensities, and subsequent growth indexes, biomass allocation patterns and photosynthesis were monitored during a 60-day period. Seven treatments were conducted in which the leaves of saplings were perforated with three or six holes per each leaf, and damaged by clipping one-third of each leaf, or they received 25, 50 and 75% defoliations during a single growing season (from April to August of 2014. Simulated insect damage and artificial defoliation decreased growth. The 75% defoliation significantly reduced the total dry mass of birch saplings at harvest by 30%, while such reduction did not influence the total productivity. The dry mass of leaves was reduced by 45% when saplings were defoliated by 75% compared to not defoliated saplings. Moreover, the total production of leaves significantly increased in the 75% defoliated saplings compared with control saplings. Artificial defoliation increased the relative biomass allocation to foliage, and this was more evident in defoliated than in mechanically insect-damaged saplings. Despite losing 25, 50 or 75% of leaf mass due to clipping, defoliated birch saplings recovered similar dry masses and root/shoot ratios by harvest as the non-defoliated saplings. Perforation and clipping parts of the leaves, as well as the artificial defoliations, caused the regrowth of biomass that did not significantly change compared to healthy silver birch saplings, and this phenomenon could be assessed as equal-compensatory growth.

  16. Wood properties of Populus and Betula in long-term exposure to elevated CO₂ and O₃.

    Science.gov (United States)

    Kostiainen, Katri; Saranpää, Pekka; Lundqvist, Sven-Olof; Kubiske, Mark E; Vapaavuori, Elina

    2014-06-01

    We studied the interactive effects of elevated concentrations of CO2 and O3 on radial growth and wood properties of four trembling aspen (Populus tremuloides Michx.) clones and paper birch (Betula papyrifera Marsh.) saplings. The material for the study was collected from the Aspen FACE (free-air CO2 enrichment) experiment in Rhinelander (WI, USA). Trees had been exposed to four treatments [control, elevated CO2 (560 ppm), elevated O3 (1.5 times ambient) and combined CO2 + O3 ] during growing seasons 1998-2008. Most treatment responses were observed in the early phase of experiment. Our results show that the CO2- and O3-exposed aspen trees displayed a differential balance between efficiency and safety of water transport. Under elevated CO2, radial growth was enhanced and the trees had fewer but hydraulically more efficient larger diameter vessels. In contrast, elevated O3 decreased radial growth and the diameters of vessels and fibres. Clone-specific decrease in wood density and cell wall thickness was observed under elevated CO2 . In birch, the treatments had no major impacts on wood anatomy or wood density. Our study indicates that short-term impact studies conducted with young seedlings may not give a realistic view of long-term ecosystem responses. PMID:24372544

  17. Responses of selected birch (Betula pendula Roth) clones to ozone change over time.

    Science.gov (United States)

    Oksanen, E.

    2003-06-01

    A long-term free air ozone fumigation experiment was conducted to study changes in physiological ozone responses during tree ontogeny and exposure time in ozone sensitive and tolerant clones of European white birch (Betula pendula Roth), originated from south and central Finland. The trees were grown in soil in natural microclimatic conditions under ambient ozone (control) and 1.4-1.7 x ambient (elevated) ozone from May 1996 to October 2001, and were measured for stem and foliage growth, net photosynthesis, stomatal conductance, stomatal density, visible injuries, foliar starch content and bud formation. After 6 years of exposure, the magnitude of ozone-induced growth reductions in the sensitive clone was 12-48% (significant difference), levels similar or greater than those reported earlier for 2- and 3-year-old saplings undergoing shorter exposures. In the tolerant clone, growth of these larger trees was reduced by 1-38% (significant difference in stem volume), although the saplings had previously been unaffected. In both clones, ozone stress led to significantly reduced leaf-level net photosynthesis but significantly increased stomatal conductance rates during the late summer, resulting in a lower carbon gain for bud formation and the onset of visible foliar injuries. Increasing ozone sensitivity with duration of exposure was explained by a change in growth form (relatively reduced foliage mass), a lower photosynthesis to stomatal conductance ratio during the late summer, and deleterious carry-over effects arising from the reduced number of over-wintering buds. PMID:12803615

  18. Genetic and environmental determinants of insect herbivore community structure in a Betula pendula population.

    Science.gov (United States)

    Silfver, Tarja; Rousi, Matti; Oksanen, Elina; Roininen, Heikki

    2014-01-01

    A number of recent studies have shown that intraspecific genetic variation of plants may have a profound effect on the herbivorous communities which depend on them. However less is known about the relative importance of intraspecific variation compared to other ecological factors, for example environmental variation or the effects of herbivore damage. We randomly selected 22 Betula pendula genotypes from a local population (block) variation on a local scale, while on a regional scale, genotypic and environmental (site) variation accounted for 4-14% of the arthropod community structure. The genetic effects were modified by environmental variation on both a local and regional scale over one study year, and locally, the largest part of the variation (38%) could be explained by the genotype × environment (block) interactions. Suppression of insect herbivores during one growing season led to changed arthropod community structure in the following growing season, but this effect was minimal and could explain only 4% of the total variation in insect community structure. Our results suggest that both genetic and environmental factors are important determinants of the community structure of herbivorous insects. Together these mechanisms appear to maintain the high diversity of insects in B. pendula forest ecosystems. PMID:24715977

  19. Community structure and regeneration types of Betula dahurica forest in Badaling forest center of Beijing

    Institute of Scientific and Technical Information of China (English)

    Zhang Yong; Zheng Zhi-hua; Zhang Zhi-xiang

    2007-01-01

    Using plant community analysis methods, we analyzed the floristic characteristics, species composition, community structure, population structure, and spatial distribution patterns of a Betula dahurica forest on the "1238" mountain of Badaling in Beijing, China. The results show that: 1) There are 33 plant species in the B. dahurica community, including 18 woody plant species. The B. dahurica forest is a monodominant community with 75.9% dominance. 2) Based on diameter at breast height (DBH)size class distribution, the population structure of B. dahurica and Acer mono-two heliophyllous and pioneer tree species is cascade-type, with both in an increasing stage. The population structure of Tilia mandshurica and T. mongolica, two shade-tolerant tree species, is inverse-J type, and they have more young seedling individuals and regenerate more stably. They are associated species of the pioneer tree species. The population structure of Quercus mongolica, as the associated species of climax species in the community, is sporadic, and its regeneration is fluctuating and random. Fraxinus rhynchophylla is a shade-tolerant tree species which has a unibar population structure and climax characteristics of pioneer tree species. The relative frequency of young seedlings reached 0.4.3) The dominant species B. dahurica is still in an increasing stage, and the regeneration of other species is steady or partly influences the community, putting the community in the pioneer species stage. From the population structure and distribution frequency ofF. rhynchophylla, the B. dahurica forest will approach to a climax state in the future.

  20. Wood anatomical analysis of Alnus incana and Betula pendula injured by a debris-flow event.

    Science.gov (United States)

    Arbellay, Estelle; Stoffel, Markus; Bollschweiler, Michelle

    2010-10-01

    Vessel chronologies in ring-porous species have been successfully employed in the past to extract the climate signal from tree rings. Environmental signals recorded in vessels of ring-porous species have also been used in previous studies to reconstruct discrete events of drought, flooding and insect defoliation. However, very little is known about the ability of diffuse-porous species to record environmental signals in their xylem cells. Moreover, time series of wood anatomical features have only rarely been used to reconstruct former geomorphic events. This study was therefore undertaken to characterize the wood anatomical response of diffuse-porous Alnus incana (L.) Moench and Betula pendula Roth to debris-flow-induced wounding. Tree microscopic response to wounding was assessed through the analysis of wood anatomical differences between injured rings formed in the debris-flow event year and uninjured rings formed in the previous year. The two ring types were examined close and opposite to the injury in order to determine whether wound effects on xylem cells decrease with increasing tangential distance from the injury. Image analysis was used to measure vessel parameters as well as fiber and parenchyma cell (FPC) parameters. The results of this study indicate that injured rings are characterized by smaller vessels as compared with uninjured rings. By contrast, FPC parameters were not found to significantly differ between injured and uninjured rings. Vessel and FPC parameters mainly remained constant with increasing tangential distance from the injury, except for a higher proportion of vessel lumen area opposite to the injury within A. incana. This study highlights the existence of anatomical tree-ring signatures-in the form of smaller vessels-related to past debris-flow activity and addresses a new methodological approach to date injuries inflicted on trees by geomorphic processes. PMID:20639516

  1. Seventeen-year trends in spring and autumn phenophases of Betula pubescens in a boreal environment

    Science.gov (United States)

    Poikolainen, Jarmo; Tolvanen, Anne; Karhu, Jouni; Kubin, Eero

    2016-08-01

    Trends in the timing of spring and autumn phenophases of Betula pubescens were investigated in the southern, middle, and northern boreal zones in Finland. The field observations were carried out at 21 sites in the Finnish National Phenological Network in 1997-2013. The effective temperature sum of the thermal growth period, i.e. the sum of the positive differences between diurnal mean temperatures and 5 °C (ETS1), increased annually on average by 6-7 degree day units. Timing of bud burst remained constant in the southern and middle boreal zones but advanced annually by 0.5 day in the northern boreal zone. The effective temperature sum at bud burst (ETS2) showed no trend in the southern and middle boreal zones, whereas ETS2 increased on average from 20-30 to 50 degree day units in the northern boreal zone, almost to the same level as in the other zones. Increase in ETS2 indicates that the trees did not start their growth in very early spring despite warmer spring temperatures. The timing of leaf colouring and leaf fall remained almost constant in the southern boreal zones, whereas these advanced annually by 0.3 and 0.6 day in the middle boreal zone and by 0.6 and 0.4 day in the northern boreal zone, respectively. The duration of the growth period remained constant in all boreal zones. The results indicate high buffering capacity of B. pubescens against temperature changes. The study also shows the importance of the duration of phenological studies: some trends in spring phenophases had levelled out, while new trends in autumn phases had emerged after earlier studies in the same network for a shorter observation period.

  2. Seventeen-year trends in spring and autumn phenophases of Betula pubescens in a boreal environment

    Science.gov (United States)

    Poikolainen, Jarmo; Tolvanen, Anne; Karhu, Jouni; Kubin, Eero

    2015-12-01

    Trends in the timing of spring and autumn phenophases of Betula pubescens were investigated in the southern, middle, and northern boreal zones in Finland. The field observations were carried out at 21 sites in the Finnish National Phenological Network in 1997-2013. The effective temperature sum of the thermal growth period, i.e. the sum of the positive differences between diurnal mean temperatures and 5 °C (ETS1), increased annually on average by 6-7 degree day units. Timing of bud burst remained constant in the southern and middle boreal zones but advanced annually by 0.5 day in the northern boreal zone. The effective temperature sum at bud burst (ETS2) showed no trend in the southern and middle boreal zones, whereas ETS2 increased on average from 20-30 to 50 degree day units in the northern boreal zone, almost to the same level as in the other zones. Increase in ETS2 indicates that the trees did not start their growth in very early spring despite warmer spring temperatures. The timing of leaf colouring and leaf fall remained almost constant in the southern boreal zones, whereas these advanced annually by 0.3 and 0.6 day in the middle boreal zone and by 0.6 and 0.4 day in the northern boreal zone, respectively. The duration of the growth period remained constant in all boreal zones. The results indicate high buffering capacity of B. pubescens against temperature changes. The study also shows the importance of the duration of phenological studies: some trends in spring phenophases had levelled out, while new trends in autumn phases had emerged after earlier studies in the same network for a shorter observation period.

  3. BpMADS4 has a central role in inflorescence initiation in silver birch (Betula pendula).

    Science.gov (United States)

    Elo, Annakaisa; Lemmetyinen, Juha; Novak, Anu; Keinonen, Kaija; Porali, Ilkka; Hassinen, Minna; Sopanen, Tuomas

    2007-09-01

    Acceleration of flowering would be beneficial for breeding trees with a long juvenile phase; conversely, inhibition of flowering would prevent the spread of transgenes from the genetically modified trees. We have previously isolated and characterized several MADS genes from silver birch (Betula pendula Roth). In this study, we investigated the more detailed function of one of them, BpMADS4, a member of the APETALA1/FRUITFULL group of MADS genes. The expression of BpMADS4 starts at very early stage of the male and female inflorescence development and the activity is high in the apex of the developing inflorescence. Later, some expression is detected in the bracts and in the flower initials. Ectopic expression of BpMADS4 accelerates flowering dramatically in normally flowering clones and also in the early-flowering birch clone, in which the earliest line flowered about 11 days after rooting, when the saplings were only 3 cm high. The birches transformed with the BpMADS4 antisense construct showed remarkable delay in flowering and the number of flowering individuals was reduced. Two of the transformed lines did not show any signs of flower development during our 2-year study, whereas all the control plants formed inflorescences within 107 days. Our results show that BpMADS4 has a critical role in the initiation of birch inflorescence development and that BpMADS4 seems to be involved in the transition from vegetative to reproductive development. Therefore, BpMADS4 provides a promising tool for the genetic enhancement of forest trees. PMID:18251933

  4. Progeny test of tetraploid Betula platyphylla and preliminary selection of hybrid parents

    Institute of Scientific and Technical Information of China (English)

    Huanwen Xu; Yu Liu; Jing Jiang; Guifeng Liu; Xiyang Zhao

    2016-01-01

    Estimating genetic parameters of parental lines through progeny testing and choosing good hybrid parents are important for genetically improving seed orchard trees. In this study, 24 tetraploid progeny seedlings were used as experimental materials, which came from test cross design:six tetraploid Betula platyphylla lines (Q33, Q13, Q103, Q19, Q83 and Q14) as female parents and four individual B. platyphylla diploid lines (F3, F4, F9 and F11) as male parents were crossed. Variance analysis of height, diame-ter, height-to-diameter ratio, and internodal distance showed that the differences between hybrid combinations reached highly significant levels. Using multi-objective decisionmaking, we performed a comprehensive assess-ment of the various hybrid combinations. Using a selection rate of 20% of the standard, five hybrids were selected;their genetic gains in average height, diameter, height-to-diameter ratio, and internodal distance were 20.95, 6.07, 13.07 and 8.96%, respectively. We also analyzed the combining ability and genetic parameter effect values of parents and hybrid combinations. The combined analysis revealed that Q13, Q103, Q33 and Q83 were superior females; F3, F4, and F9 were superior males; and F3 9 Q13, F4 9 Q83 and F9 9 Q33 were superior hybrid combinations. The heights and diameters of these proge-nies were 22.49 and 11.48% greater than average, respectively.

  5. Influence of meteorological parameters and air pollution on hourly fluctuation of birch (Betula L.) and ash (Fraxinus L.) airborne pollen.

    Science.gov (United States)

    Puc, Małgorzata

    2012-01-01

    Pollen grains are one of the most important groups of atmospheric biological particles that originate allergic processes. Knowledge of intradiurnal variation of the atmospheric pollen may be useful for the treatment and prevention of pollen allergies. Intradiurnal fluctuation of hourly pollen counts in 24 h are related to the daily rhythm of anther opening, and modified by various interacting factors. Flowering and pollen production of individual species are influenced by genetic, phenological, ecological, meteorological and climatic factors. Estimation of the intradiurnal variability in the pollen count permits evaluation of the threat posed by allergens over a given area. Measurements performed in Szczecin over a period of 7 years (2006-2012) permitted analysis of hourly variation of the pollen count of birch (Betula) and ash (Fraxinus) in 24 h, and evaluation of the impact of weather conditions and the concentration of gas air pollutants on the intradiurnal patterns of both taxa. Aerobiological monitoring was conducted using a Hirst volumetric trap (Lanzoni VPPS 2000). Consecutive phases during the day were defined as 1, 5, 25, 50, 75, 95, 99% of annual total pollen. The analysis revealed that 50% of total daily pollen was noted at 14:00 for Betula and Fraxinus. The hourly distribution of birch pollen count skewed to the left and the majority of pollen of this taxon appears in the air in the first 12 hours of the day. However, for ash, the hourly distribution of pollen count skewed to the right. Statistically significant correlation was noted between the Betula and Fraxinus pollen concentration and the mean air temperature, relative humidity, wind speed, air pressure, total radiation and nitrogen oxides (NO(x)). PMID:23311785

  6. CHANGES OF CUTICLE SURFACE LIPIDS OF POPULUS ITALICA AND BETULA PENDULA CAUSED BY POLLUTION

    Directory of Open Access Journals (Sweden)

    Zubrovskaya O. M.

    2014-08-01

    Full Text Available Arboreal plants intensively accumulate heavy metals, resulting in a corresponding revocation level of physiological processes. The lipid components operate an important role in the formation of plant resistance. Therefore, it was very important to determine the characteristics of lipid peroxidation flow in leaves of arboreal plants, and changes in the composition of cuticle surface lipids at different levels of heavy metal accumulation. Research objects were Populus italica (Du Roi Moench and Betula pendula Roth. of second age group, growing on the industrial site РJSC ‘Kryvyi Rig Factory of minium’ (with strong contamination and in the arboretum of Kryvyi Rig Botanic Garden, National Academy of Science of Ukraine (conventional control. Leaves were taken from the middle of the crown southwest exposure in phase of leaf full separation and 5-10 day of phase finishing point of their growth. It was shown that P. italica maximally accumulated zinc, content of which was increased in the phase of leaf full separation and on 5-10 day of phase of leaf growth finishing point relative to the control to 12,6 and 23 times respectively. The accumulation level of heavy metals was typically less significant for assimilation organs of B. pendula compared to P. italica. Thus, the content of zinc and lead in the leaves during the study increased only in 2 times towards control. The leaves of B. pendula, unlike P. italica, more intensively accumulated cadmium in the phase of leaf full separation and on 5-10 day of phase finishing point of their growth (it was 6 and 15 times higher relative to control respectively. It was obviously connected to the fact that the surface texture of poplar leaves may cause intense sticking of dust particles containing heavy metals and penetration into the leaves. The effect of heavy metals in both phases of leaf morphogenesis caused an increase in lipid peroxidation by 40-52% for P. italica and almost by 3 times for B. pendula

  7. Effects of intensive harvesting on forest floor properties in Betula papyrifera stands in Newfoundland

    International Nuclear Information System (INIS)

    This study investigates litter and organic matter production and related site ecology in nine medium to high quality Betula papyrifera stands in three locations in central Newfoundland on a variety of land form and drainage conditions. Three sites, Badger West (BW), Moose Pond (MP) and Middleton Lake (ML) were selected. The ML site has the highest quality (with the best height/age ratio, 18 m/60 yr, and height/DBH ratio, 18 m/30 cm), followed by MP and BW. Litter depth on well developed moders or mulls was usually 2 - 3 cm and varied from 1 - 15 cm. Forest floor depths (measured in 324 profiles) rarely reached 20 cm and was commonly 5 - 10 cm; it varied with position and site. Total and available nutrients indicate that B. papyrifera produces one of the highest-quality organic matter types of the local forest types and is important in improving site quality. The mean N-concentration in green foliage (2.21 %) and trapped litter (1.03 %) was highest at the best quality site ML, followed by MP and BW. The concentration of calcium, 0.85 %, was highest at the poorest quality site. Four years after harvesting, litter depth significantly decreased in all sites and treatments with the exception of the BW whole-tree harvest treatment. Total forest floor depth significantly decreased at all sites in the stem-only harvest treatment as well as the MP whole-tree harvest treatment. There was a significant decrease in available nitrogen following harvesting in both treatments at both the MP and BW sites. Change in available phosphorus was insignificant, with the exception of an increase in the MP stem-only harvest treatment. There was a significant decrease in available potassium at both the ML and BW whole-tree harvest treatments, but a significant increase in the stem-only harvest treatments at ML and MP. There was a significant decrease in available calcium in both treatments at both the MP and BW sites 34 refs, 4 figs, 1 tab

  8. Tree competition and species coexistence in a Quercus--Betula forest in the Dongling Mountains in northern China

    Science.gov (United States)

    Hou, Ji-hua; Mi, Xiang-cheng; Liu, Can-ran; Ma, Ke-ping

    2006-09-01

    The population size structure, growth dynamics and mode of competition among adult trees (≥ 4 cm DBH) of six abundant tree species in a 5 ha study plot of a temperate deciduous forest in the Dongling Mountains in northern China were investigated using diffusion and growth dynamics models. In the year of 2000, two dominant species, Quercus liaotungensis and Betula dahurica accounted for ca. 68.69% of the total basal area and 52.71% of the total density of adult plants. Q. liaotungensis, Populus davidiana and Acer mono exhibited inverse J-shaped DBH distributions whereas Betula dahurica, B. platyphylla and Salix caprea had unimodal DBH distributions. One-sided interspecific competition was detected between some species combinations at the scale of the 5 ha study plot, and the competitive effect was mainly size-dependent rather than from species-specific interactions with large individuals in the canopy layer out competing smaller individuals in the understory. Symmetric competition was found between Q. liaotungensis and A. mono only. However, considering the straight line relationship of G ( t, x) - √{D(t, x)}, which suggests that competitive asymmetry is very low or absent, combined with the relatively low mortality of trees with a DBH larger than 4 cm, we speculate that asymmetric interspecific competition was not important in structuring this tree community. Regeneration characteristics of each species are most likely important in regulating species coexistence and stand dynamics in this forest.

  9. [Spatial patterns of dominant tree species in sub-alpine Betula-Abies forest in West Sichuan of China].

    Science.gov (United States)

    Miao, Ning; Liu, Shi-Rong; Shi, Zuo-Min; Yu, Hong; Liu, Xing-Liang

    2009-06-01

    Based on the investigation in a 4 hm2 Betula-Abies forest plot in sub-alpine area in West Sichuan of China, and by using point pattern analysis method in terms of O-ring statistics, the spatial patterns of dominant species Betula albo-sinensis and Abies faxoniana in different age classes in study area were analyzed, and the intra- and inter-species associations between these age classes were studied. B. albo-sinensis had a unimodal distribution of its DBH frequency, indicating a declining population, while A. faxoniana had a reverse J-shaped pattern, showing an increasing population. All the big trees of B. albo-sinensis and A. faxoniana were spatially in random at all scales, while the medium age and small trees were spatially clumped at small scales and tended to be randomly or evenly distributed with increasing spatial scale. The maximum aggregation degree decreased with increasing age class. Spatial association mainly occurred at small scales. A. faxoniana generally showed positive intra-specific association, while B. albo-sinensis generally showed negative intra-specific association. For the two populations, big and small trees had no significant spatial association, but middle age trees had negative spatial association. Negative inter-specific associations of the two populations were commonly found in different age classes. The larger the difference of age class, the stronger the negative inter-specific association. PMID:19795631

  10. Growth response of downy birch (Betula pubescens) to moisture treatment at an cut-over peat bog in the Šumava Mts., Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Lanta, Vojtěch; Hazuková, I.

    2005-01-01

    Roč. 42, - (2005), s. 247-256. ISSN 0003-3847 R&D Projects: GA ČR GD206/03/H034 Institutional research plan: CEZ:AV0Z6005908 Keywords : Betula pubescens * cut-over peatland * increment Subject RIV: EF - Botanics Impact factor: 0.315, year: 2005

  11. Phenolic compounds of the inner bark of Betula pendula: seasonal and genetic variation and induction by wounding.

    Science.gov (United States)

    Liimatainen, Jaana; Karonen, Maarit; Sinkkonen, Jari; Helander, Marjo; Salminen, Juha-Pekka

    2012-11-01

    The contents of individual phenolic compounds in the inner bark of silver birch (Betula pendula Roth) were analyzed by HPLC-DAD. Samples from 21 mature trees originating from three micropropagated parent trees were collected six times over a 1-year period. Significant seasonal variation in the quantities of ten compounds and four chromatographically unresolved compound pairs was found. A majority of the compounds also exhibited significant quantitative variation among birch clones. There were no qualitative differences associated with the season or among the clones. However, wounding of the bark induced the production of new types of bark phenolics: several ellagitannins were detected in the callus tissues of birch for the first time. PMID:23065107

  12. Overexpression of a MADS-box gene from birch (Betula platyphylla promotes flowering and enhances chloroplast development in transgenic tobacco.

    Directory of Open Access Journals (Sweden)

    Guan-Zheng Qu

    Full Text Available In this study, a MADS-box gene (BpMADS, which is an ortholog of AP1 from Arabidopsis, was isolated from birch (Betula platyphylla. Transgenic Arabidopsis containing a BpMADS promoter::GUS construct was produced, which exhibited strong GUS staining in sepal tissues. Ectopic expression of BpMADS significantly enhanced the flowering of tobacco (35S::BpMADS. In addition, the chloroplasts of transgenic tobacco exhibited much higher growth and division rates, as well rates of photosynthesis, than wild-type. A grafting experiment demonstrated that the flowering time of the scion was not affected by stock that overexpressed BpMADS. In addition, the overexpression of BpMADS resulted in the upregulation of some flowering-related genes in tobacco.

  13. Effects of ozone impact on the gas exchange and chlorophyll fluorescence of juvenile birch stems (Betula pendula Roth.)

    International Nuclear Information System (INIS)

    Effects of ozone impact on gas exchange and chlorophyll fluorescence of juvenile birch (Betula pendula) stems and leaves were investigated. Significant differences in the response of leaves and stems to ozone were found. In leaves, O3 exposure led to a significant decline in photosynthetic rates, whereas stems revealed an increased dark respiration and a concomitant increase in corticular photosynthesis. In contrast to birch leaves, corticular photosynthesis appeared to support the carbon balance of stems or even of the whole-tree under O3 stress. The differences in the ozone-response between leaves and stems were found to be related to ozone uptake rates, and thus to inherent differences in leaf and stem O3 conductance. - Leaves of birch were more affected by ozone fumigation than corresponding stems, due to a higher ozone uptake rate

  14. Solar UV-B effects on PSII performance in Betula nana are influenced by PAR level and reduced by EDU

    DEFF Research Database (Denmark)

    Albert, Kristian Rost; Mikkelsen, Teis Nørgaard; Ro-Poulsen, Helge;

    2012-01-01

    The long-term and diurnal responses of photosystem II (PSII) performance to near-ambient UV-B radiation were investigated in High Arctic Betula nana. We conducted an UV exclusion experiment with five replicated blocks consisting of open control (no filter), photosynthetic active radiation and UV...... effects of UV-B. Chlorophyll-a fluorescence induction curves were used for analysis of OJIP test parameters. Near-ambient UV-B radiation reduced across season maximum quantum yield (TRo /ABS = Fv /Fm ), approximated number of active PSII reaction center (RC/ABS) and the performance index (PIABS ), despite...... in reduced UV-B compared to near-ambient UV-B. This demonstrates current solar UV-B to reduce the PSII performance both on a daily as well as a seasonal basis in this High Arctic species....

  15. Effects of decadal exposure to interacting elevated CO2 and/or O3 on paper birch (Betula papyrifera) reproduction

    International Nuclear Information System (INIS)

    We studied the effects of long-term exposure (nine years) of birch (Betula papyrifera) trees to elevated CO2 and/or O3 on reproduction and seedling development at the Aspen FACE (Free-Air Carbon Dioxide Enrichment) site in Rhinelander, WI. We found that elevated CO2 increased both the number of trees that flowered and the quantity of flowers (260% increase in male flower production), increased seed weight, germination rate, and seedling vigor. Elevated O3 also increased flowering but decreased seed weight and germination rate. In the combination treatment (elevated CO2 + O3) seed weight is decreased (20% reduction) while germination rate was unaffected. The evidence from this study indicates that elevated CO2 may have a largely positive impact on forest tree reproduction and regeneration while elevated O3 will likely have a negative impact. - In this study, we found that elevated CO2 enhances and elevated O3 decreases birch reproduction and early seedling growth

  16. Sezonske varijacije koncentracije specifi čnog IgE-a prema alergenu Betula verrucosa, Bet v

    OpenAIRE

    Dodig, Slavica; Petković, Giorgie; Kristić Kirin, Branka

    2015-01-01

    Cilj je ispitati sezonske razlike u koncentraciji ukupnog IgE-a (uIgE-a), specifi čnog IgE-a (sIgE) prema alergenu breze, Betula verrucosa - Bet v, te indeks sIgE-a (I-sIgE) u djece preosjetljive na alergen breze, Bet v. Ispitana su djeca s astmom i/ili rinitisom (N=19), preosjetljiva na alergen Bet v. Standardiziranom fl uoroimunikemijskom metodom UniCAP određena je koncentracija uIgE-a, sIgE-a prema Bet v, te izračunat I-sIgE. Odabrani biomarkeri određivani su u sezoni peludacije b...

  17. Characterization of PR-10 genes from eight Betula species and detection of Bet v 1 isoforms in birch pollen

    Directory of Open Access Journals (Sweden)

    van't Westende Wendy PC

    2009-03-01

    Full Text Available Abstract Background Bet v 1 is an important cause of hay fever in northern Europe. Bet v 1 isoforms from the European white birch (Betula pendula have been investigated extensively, but the allergenic potency of other birch species is unknown. The presence of Bet v 1 and closely related PR-10 genes in the genome was established by amplification and sequencing of alleles from eight birch species that represent the four subgenera within the genus Betula. Q-TOF LC-MSE was applied to identify which PR-10/Bet v 1 genes are actually expressed in pollen and to determine the relative abundances of individual isoforms in the pollen proteome. Results All examined birch species contained several PR-10 genes. In total, 134 unique sequences were recovered. Sequences were attributed to different genes or pseudogenes that were, in turn, ordered into seven subfamilies. Five subfamilies were common to all birch species. Genes of two subfamilies were expressed in pollen, while each birch species expressed a mixture of isoforms with at least four different isoforms. Isoforms that were similar to isoforms with a high IgE-reactivity (Bet v 1a = PR-10.01A01 were abundant in all species except B. lenta, while the hypoallergenic isoform Bet v 1d (= PR-10.01B01 was only found in B. pendula and its closest relatives. Conclusion Q-TOF LC-MSE allows efficient screening of Bet v 1 isoforms by determining the presence and relative abundance of these isoforms in pollen. B. pendula contains a Bet v 1-mixture in which isoforms with a high and low IgE-reactivity are both abundant. With the possible exception of B. lenta, isoforms identical or very similar to those with a high IgE-reactivity were found in the pollen proteome of all examined birch species. Consequently, these species are also predicted to be allergenic with regard to Bet v 1 related allergies.

  18. Influence of different particle sizes in the bark chemical composition of Eucalyptus globulus Labill., Betula pendula Roth, Picea abies (L.) Karst, Pinus sylvestris L. e Pinus pinea L.

    OpenAIRE

    Mirra, Inês Martins Pereira

    2011-01-01

    Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia The goal of this report is to characterize the bark of five industrially important forest species in Europe - Eucalyptus globulus, Betula pendula, Picea abies, Pinus sylvestris e Pinus pinea and to define their potential use as a source of value added chemical products. It was performed the anatomical characterization of bark tissues (dissociated elements), the selective fractionation (si...

  19. What was behind the bark? : An assessment of decay among urban Tilia, Betula and Acer trees felled as hazardous in the Helsinki City area

    OpenAIRE

    Terho, Minna

    2009-01-01

    Old trees growing in urban environments are often felled due to symptoms of mechanical defects that could be hazardous to people and property. The decisions concerning these removals are justified by risk assessments carried out by tree care professionals. The major motivation for this study was to determine the most common profiles of potential hazard characteristics for the three most common urban tree genera in Helsinki City: Tilia, Betula and Acer, and in this way improve management pract...

  20. Ectomycorrhizal Community Structure of Salix and Betula spp. at a Saline Site in Central Poland in Relation to the Seasons and Soil Parameters

    OpenAIRE

    Hrynkiewicz, Katarzyna; Szymańska, Sonia; Piernik, Agnieszka; Thiem, Dominika

    2015-01-01

    Saline stress is one of the most important abiotic factors limiting the growth and development of plants and associated microorganisms. While the impact of salinity on associations of arbuscular fungi is relatively well understood, knowledge of the ectomycorrhizal (EM) fungi of trees growing on saline land is limited. The main objective of this study was to determine the density and diversity of EM fungi associated with three tree species, Salix alba, Salix caprea and Betula pendula, growing ...

  1. Exogenous GA₃ Application Enhances Xylem Development and Induces the Expression of Secondary Wall Biosynthesis Related Genes in Betula platyphylla.

    Science.gov (United States)

    Guo, Huiyan; Wang, Yucheng; Liu, Huizi; Hu, Ping; Jia, Yuanyuan; Zhang, Chunrui; Wang, Yanmin; Gu, Shan; Yang, Chuanping; Wang, Chao

    2015-01-01

    Gibberellin (GA) is a key signal molecule inducing differentiation of tracheary elements, fibers, and xylogenesis. However the molecular mechanisms underlying the effect of GA on xylem elongation and secondary wall development in tree species remain to be determined. In this study, Betula platyphylla (birch) seeds were treated with 300 ppm GA₃ and/or 300 ppm paclobutrazol (PAC), seed germination was recorded, and transverse sections of hypocotyls were stained with toluidine blue; the two-month-old seedlings were treated with 50 μM GA₃ and/or 50 μM PAC, transverse sections of seedling stems were stained using phloroglucinol-HCl, and secondary wall biosynthesis related genes expression was analyzed by real-time quantitative PCR. Results indicated that germination percentage, energy and time of seeds, hypocotyl height and seedling fresh weight were enhanced by GA₃, and reduced by PAC; the xylem development was wider in GA₃-treated plants than in the control; the expression of NAC and MYB transcription factors, CESA, PAL, and GA oxidase was up-regulated during GA₃ treatment, suggesting their role in GA₃-induced xylem development in the birch. Our results suggest that GA₃ induces the expression of secondary wall biosynthesis related genes to trigger xylogenesis in the birch plants. PMID:26404260

  2. Exogenous GA3 Application Enhances Xylem Development and Induces the Expression of Secondary Wall Biosynthesis Related Genes in Betula platyphylla

    Directory of Open Access Journals (Sweden)

    Huiyan Guo

    2015-09-01

    Full Text Available Gibberellin (GA is a key signal molecule inducing differentiation of tracheary elements, fibers, and xylogenesis. However the molecular mechanisms underlying the effect of GA on xylem elongation and secondary wall development in tree species remain to be determined. In this study, Betula platyphylla (birch seeds were treated with 300 ppm GA3 and/or 300 ppm paclobutrazol (PAC, seed germination was recorded, and transverse sections of hypocotyls were stained with toluidine blue; the two-month-old seedlings were treated with 50 μM GA3 and/or 50 μM PAC, transverse sections of seedling stems were stained using phloroglucinol–HCl, and secondary wall biosynthesis related genes expression was analyzed by real-time quantitative PCR. Results indicated that germination percentage, energy and time of seeds, hypocotyl height and seedling fresh weight were enhanced by GA3, and reduced by PAC; the xylem development was wider in GA3-treated plants than in the control; the expression of NAC and MYB transcription factors, CESA, PAL, and GA oxidase was up-regulated during GA3 treatment, suggesting their role in GA3-induced xylem development in the birch. Our results suggest that GA3 induces the expression of secondary wall biosynthesis related genes to trigger xylogenesis in the birch plants.

  3. Genetic diversity of Betula luminifera populations at different elevations in Wuyi Mountain and its association with ecological factors

    Institute of Scientific and Technical Information of China (English)

    Yiqing XIE; Zhizhen LI; Ruzhu HUANG; Xiangxi XIAO; Yong HUANG

    2009-01-01

    The random amplified polymorphic DNA (RAPD) technique was used to evaluate the genetic diversity and population structure of 91 genets from four wild populations of Betula luminifera at different eleva-tions in the National Nature Reserve of the Wuyi Mountain,Fujian Province, China. Eighteen random primers (from 139 primers) produced a total of 199 scorable amplified fragments, of which 174 (87.44%) were polymorphic across all individuals. The genetic diversities of B.luminifera at the population level and species level were PPL = 60.05%, h = 0.2242, I= 0.3181 and PPL = 87.44%,h = 0.3442, I= 0.4899, respectively. The value of differ-entiation (Gst= 0.3486) and analysis of molecular variance (AMOVA) indicated that there was a relatively high genetic differentiation among populations, and about one-third of the genetic variation occurred among populations. Pearson correlation analysis further revealed that the genetic diversity within populations had significant or very significant correlation with the elevation, climatic factors (annual average temperature and annual precipitation) and soil nutrient factors (total nitrogen, C/N ratio and organic matter). Mantel tests show that there was a significant correlation between the genetic distances among popula-tions and the distance of elevation, and the divergence of soil nutrient factors. The results of the present study suggested that the relatively high genetic differentiation among populations ofB. luminifera at different elevations might be caused by ecological factors and gene flow.

  4. The Effects of Surface Roughness on Adhesion Strength of Coated Ash (Fraxinus excelsior L. and Birch (Betula L. Wood

    Directory of Open Access Journals (Sweden)

    Justina VITOSYTĖ

    2012-12-01

    Full Text Available For the evaluation of surface roughness impact on adhesion properties, the samples of dried ash (Fraxinus excelsior L. and birch (Betula L. wood were used. Before wood finishing, the surfaces of the samples were sanded. In order to get different surface roughness the abrasive material of P80, P120, P150, P180, P220 and P240 grit was used. The parameters of surface roughness Ra, Rz and Rmax were measured in three directions: along the wood grain, across the grain and in the angle of 45º. Comparison of the results showed the non-linear dependency of roughness parameters. Afterwards the wood surface was coated with three different acrylic-polyurethane coating systems (1 layer of varnish without primer, 1 layer of primer and 1 layer of varnish, and 1 layer of primer and 2 layers of varnish. The adhesion strength was assessed using the pull-off method. Also the nature of the fracture was evaluated. It was determined that the peculiarities of surface roughness, coating system type and wood species signally results the values of the adhesion strength.DOI: http://dx.doi.org/10.5755/j01.ms.18.4.3094

  5. Effects of reindeer on the re-establishment of Betula pubescens subsp. czerepanovii and Salix phylicifolia in a subarctic meadow

    Directory of Open Access Journals (Sweden)

    Michael den Herder

    2003-04-01

    Full Text Available The effect of reindeer browsing on the regeneration of Betula pubescens subsp. czerepanovii and Salix phylicifolia was studied in a subarctic meadow in Finnish Lapland. The aim of the study was to see whether tree recovery from seeds is possible under heavy reindeer-browsing pressure. After removal of the ground and field layer vegetation in 1986, two exclosures were established so that the effect of reindeer on the secondary succession, starting from seeds, could be studied. The size and the number of B. pubescens and S. phylicifolia were recorded in 1994, 1996, 1997 and 1999. Reindeer significantly reduced the height and the number of saplings (plants > 10 cm high of B. pubescens and S. phylicifolia but the number of seedlings (plants < 10 cm high did not differ between browsed and unbrowsed plots. Furthermore the heightclass distribution of saplings was different inside the exlosures compared to control areas. Over time browsed plots continued to have high densities of small saplings while in protected plots an increasing number of larger saplings appeared. In our study site, regeneration from seeds seemed possible although the height of B. pubescens and S. phylicifolia was limited by reindeer. 

  6. Effects of long-term open-field ozone exposure on leaf phenolics of European silver birch (Betula pendula Roth).

    Science.gov (United States)

    Saleem, A; Loponen, J; Pihlaja, K; Oksanen, E

    2001-05-01

    The response of phenolic compounds as a result of long-term low open-field ozone exposure was studied in ozone-sensitive and ozone-tolerant clones of European silver birch (Betula pendula Roth). The saplings were exposed to 1.5-1.6 times the ambient (elevated) ozone and ambient air (as control) over three growing seasons from May 1996 until August 1998. Quantification by modified Folin-Ciocalteau assay showed a 16.2% increase in total phenolics in elevated ozone plants as compared to that in controls and a corresponding 9.9% increase of 10 phenolic compounds quantified by HPLC. Five nonflavonoids and five flavonoids showed 8.4% and 11.4% increases, respectively. The phenolic results indicated slightly higher ozone sensitivity of clone 5 as compared to clone 2. The most ozone-responsive phenolic compounds in clone 2 and clone 5 were (+)-catechin (CT), chlorogenic acid (CGA), 5-p-coumaroylquinic acid (5CQA), 3-p-coumaroylquinic acid (3CQA), myricetin galactopyranoside (MG), quercetin-3-O-glucuronopyranoside (QGR), and quercetin-3-O-arabinofuranoside (QA). Increased phenolic content in ozone-exposed plants was related to impaired growth and accelerated leaf senescence, indicated by enhanced autumn leaf yellowing and lower chlorophyll and Mg content. The change in carbon allocation towards defensive phenolics at the expense of growth was greater in the ozone-sensitive clone as compared to tolerant clone. PMID:11471939

  7. Effects of long-term, elevated ultraviolet-B radiation on phytochemicals in the bark of silver birch (Betula pendula).

    Science.gov (United States)

    Tegelberg, Riitta; Aphalo, Pedro J; Julkunen-Tiitto, Riitta

    2002-12-01

    Long-term outdoor experiments were conducted to investigate the effects of elevated ultraviolet-B (UV-B, 280-320 nm) radiation on secondary metabolites (phenolics and terpenoids) and the main soluble sugars (sucrose, raffinose and glucose) in the bark of silver birch (Betula pendula Roth) saplings. Saplings were exposed to a constant 50% increase in erythemal UV irradiance (UV-B(CIE); based on the CIE (International Commission on Illumination) erythemal action spectrum) and a small increase in UV-A radiation (320-400 nm) for three growing seasons in an irradiation field in central Finland. Two control groups were used: saplings exposed to ambient radiation and saplings exposed to slightly increased UV-A radiation. Concentrations of sucrose, raffinose and glucose in bark were higher in UV-treated saplings than in saplings grown in ambient radiation, indicating that stem carbohydrate metabolism was changed by long-term elevated UV radiation. Saplings in the elevated UV-A + UV-B radiation treatment and the UV-A radiation control treatment had significantly increased concentrations of certain UV-absorbing phenolics, such as salidroside, 3,4'-dihydroxypropiophenone-3-glucoside, (+)-catechin and (-)-epicatechin compared with saplings in ambient radiation. In contrast, the radiation treatments had no effect on the non-UV-B-absorbing terpenoids, papyriferic acid and deacetylpapyriferic acid. We conclude that plant parts, in addition to leaves, accumulate specific phenolic UV-filters in response to UV radiation exposure. PMID:12464579

  8. Modelling of the spring phenological phases of the Silver birch Betula pendula and Bird cherry Padus racemosa in Baltic region

    Science.gov (United States)

    Kalvāns, Andis; Kalvāne, Gunta; Bitāne, Māra; Cepīte-Frišfelde, Daiga; Sīle, Tija; Seņņikovs, Juris

    2014-05-01

    The air temperature is the strongest driving factor of the plant development during spring time in moderate climate conditions. However other factors such as the air temperature during the dormancy period and light conditions can play a role as well. The full potential of the recent and historical phenological observation data can be utilised by modelling tools. We have calibrated seven phenological models described in scientific literature to calculate the likely dates leaf unfolding and start of flowering of the Silver birch Betula pendula and bird cherry Padus racemosa (Kalvāns at al, accepted). Phenological observations are derived from voluntary observation network for period 1960-2009 in Latvia. The number of used observations for each phase range from 149 to 172. Air temperature data measured in meteorological stations closest to the corresponding phenological observation sites are obtained from Latvian Environment, Geology and Meteorology Centre. We used 33 random data subsamples for model calibration to produce a range of model coefficients enabling the estimation of the phenological model uncertainty. It is found that the best reproduction of the observational data are obtained using a simple linear degree day model considering daily minimum and maximum temperature and more complex sigmoidal model honouring the need for low temperatures for dormancy release (UniChill, Chuine, 2000). The median calibration base temperature in the degree day model for the silver birch leaf unfolding is 5.6°C and for start of the flowering 6.7°C; for the bird cherry the corresponding base temperatures are 3.2°C and 3.4°C. The calibrated models and air temperature archive data derived from the Danish Meteorological Institute is used to simulate the respective phase onset in the Estonia, Latvia and Lithuania in 2009. Significant regional differences between modelled phase onset times are observed. There is a wide regional variation of the model uncertainty as well

  9. Birch (Betula spp.) wood biochar is a potential soil amendment to reduce glyphosate leaching in agricultural soils.

    Science.gov (United States)

    Hagner, Marleena; Hallman, Sanna; Jauhiainen, Lauri; Kemppainen, Riitta; Rämö, Sari; Tiilikkala, Kari; Setälä, Heikki

    2015-12-01

    Glyphosate (N-(phosphonomethyl) glycine), a commonly used herbicide in agriculture can leach to deeper soil layers and settle in surface- and ground waters. To mitigate the leaching of pesticides and nutrients, biochar has been suggested as a potential soil amendment due to its ability to sorb both organic and inorganic substances. However, the efficiency of biochar in retaining agro-chemicals in the soil is likely to vary with feedstock material and pyrolysis conditions. A greenhouse pot experiment, mimicking a crop rotation cycle of three plant genera, was established to study the effects of pyrolysis temperature on the ability of birch (Betula sp.) wood originated biochar to reduce the leaching of (i) glyphosate, (ii) its primary degradation product AMPA and (iii) phosphorus from the soil. The biochar types used were produced at three different temperatures: 300 °C (BC300), 375 °C (BC375) and 475 °C (BC475). Compared to the control treatment without biochar, the leaching of glyphosate was reduced by 81%, 74% and 58% in BC300, BC375 and BC475 treated soils, respectively. The respective values for AMPA were 46%, 39% and 23%. Biochar had no significant effect on the retention of water-soluble phosphorus in the soil. Our results corroborate earlier findings on pesticides, suggesting that biochar amendment to the soil is a promising way to reduce also the leaching of glyphosate. Importantly, the ability of biochar to adsorb agro-chemicals depends on the temperature at which feedstock is pyrolysed. PMID:26342266

  10. Effect of air pollutant NO2 on Betula pendula, Ostrya carpinifolia and Carpinus betulus pollen fertility and human allergenicity

    International Nuclear Information System (INIS)

    Pollen of Betula pendula, Ostrya carpinifolia and Carpinus betulus was exposed in vitro to two levels of NO2 (about 0.034 and 0.067 ppm) – both below current atmospheric hour-limit value acceptable for human health protection in Europe (0.11 ppm for NO2). Experiments were performed under artificial solar light with temperature and relative humidity continuously monitored. The viability, germination and total soluble proteins of all the pollen samples exposed to NO2 decreased significantly when compared with the non-exposed. The polypeptide profiles of all the pollen samples showed bands between 15 and 70 kDa and the exposure to NO2 did not produce any detectable changes in these profiles. However, the immunodetection assays indicated higher IgE recognition by patient sera sensitized to the pollen extracts from all exposed samples in comparison to the non-exposed samples. The common reactive bands to the three pollen samples correspond to 58 and 17 kDa proteins. -- Highlights: • A synthetic atmosphere containing relatively low levels of the air pollutant NO2 was simulated. • Betulaceae pollen was in vitro exposed to low levels of atmospheric NO2 pollutant. • The fertility of the Betulaceae pollen exposed to NO2 decreased significantly. • The human allergenicity of the Betulaceae pollen exposed to NO2 increased. -- When the pollen of birch trees were exposed to low levels of air pollutant NO2, a decrease in the fertility, and an increase on the allergic reactivity, were observed

  11. Large-scale climate variability and its effects on mean temperature and flowering time of Prunus and Betula in Denmark

    Science.gov (United States)

    Gormsen, A. K.; Hense, A.; Toldam-Andersen, T. B.; Braun, P.

    2005-08-01

    Large-scale climate variability largely affects average climatic conditions and therefore is likely to influence the phenology of plants. In NW-Europe, the North Atlantic Oscillation (NAO) particularly influences winter climate and, through climate interactions on plants, flowering time of all tree species. In Denmark, like in many other NW-European countries, flowering of most tree species has become earlier since the end of the 1980’s. To quantify a possible relation between NAO and flowering time of tree species, two sources of phenological information from the Copenhagen area (Denmark) were analysed, i.e. pollen counts of the genus Betula and observed first bloom dates of Prunus avium. The Winter NAO explained 29 and 37% of the variation of monthly mean temperature for February and March, respectively. The influence of temperature on flowering time was up to 56% to 60% for the February April mean. A direct correlation of Winter NAO-index and flowering time also revealed a clear relation but the time of influence was earlier (December to February). This was shown to be the likely result of a combination of direct and time-lagged effects of the NAO on air and sea surface temperature. The NAO signal is apparently stored in the North Sea and then influences temperature east up to the Baltic States. It is shown that Denmark is right in the centre of direct and time-lagged effects of the NAO. This offers the possibility of using the NAO-index for predicting flowering time of Prunus avium. The beginning of pollen flow appears to be influenced too much by short-term perturbations of the climate system decreasing the value of the NAO-index for prediction. However, it indicates a close relationship between natural climate variability, measured by the NAO index, and flowering time of tree species for Denmark.

  12. Foliar responses of understorey Abies lasiocarpa to different degrees of release cutting of Betula papyrifera and conifer mixed species stand

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.R.; Letchford, T. [Ministry of Forests, Prince George, BC (Canada). Red Rock Research Station; Comeau, P.G. [BC Ministry of Forests, Victoria, BC (Canada); Coopersmith, D. [BC Ministry of Forests, Prince George, BC (Canada)

    2000-07-01

    Foliar responses of subalpine fir (Abies lasiocarpa (Hook.) Nutt.) to thinning were studied in a 35-yr-old mixed stand of paper birch (Betula papyrifera Marsh.) and conifers. The stand regenerated naturally after a wildfire with a canopy dominated by paper birch (average height 9.8 m) and an understorey dominated by subalpine fir (average height 1.6 m). The stand was thinned to four densities of birch: 0, 600 and 1200 stems ha{sup -1} and control (Unthinned at 2300-6400 stems ha{sup -1}) in the autumn of 1995. The understorey conifers, mainly subalpine fir, were thinned to 1200 stems ha{sup -1}. The study used a completely randomized split-plot design. Three sample trees were systematically selected from each treatment replicate and each tree stratum (upper, intermediate and lower understorey). One-year-old and older age class needles were collected from one south-facing branch within the fifth whorl from the tree top. Thinning of paper birch significantly (p<0.001) increased leaf area and dry weight per 100 needles for intermediate and short trees except in the 0 birch treatment. Understorey subalpine fir trees in 600 stems ha{sup -1} birch (T3) had the largest leaf area and leaf dry weight per 100 1-yr-old needles. Specific leaf area (SLA) decreased from unthinned (T1) to 0 birch (T4). Lower understorey trees had the largest SLA. One-year-old needles had significantly higher N, P and K concentrations in all the thinning treatments. These responses are consistent with the shade tolerance of subalpine fir. The results suggest that when managing a paper birch-conifers mixed wood forest it may be of benefit to understorey conifers to leave a birch canopy as a nursing crop.

  13. Responses of two birch ( Betula pendula Roth) clones to different ozone profiles with similar AOT40 exposure

    Science.gov (United States)

    Oksanen, Elina; Holopainen, Toini

    Saplings of two clones of European white birch ( Betula pendula Roth) were exposed to three different ozone profiles resulting in same AOT40 value of 13-14 ppm h in a chamber experiment. The sensitive clone 5 and the more tolerant clone 2 were growing (1) under filtered air (=control), or (2) were exposed to 70 ppb ozone for 24 h d -1 (=profile 1), (3) to 100 ppb ozone for 12 h d -1 at 8:00-20:00 (=profile 2), or (4) to 200 ppb ozone for 4.5 h d -1 at 9:30-14:00 (=profile 3) for 20 d. The saplings were determined for growth, visible leaf injuries, stomatal conductance, and concentrations of Rubisco, chlorophyll and carotenoids. Growth responses and induction of visible foliar injuries under different ozone profiles were variable, resulting in 4-17% lower dry mass of shoot, 16-46% reduction in stem height increment and 11-43% increase in visible injuries in clone 5, which was accompanied by higher leaf turnover rate under profile 3 indicating compensation growth. In clone 2, ozone-induced responses ranged from slight stimulation in stem height growth to 13% decrease in dry mass of shoot and 2-16% increase in visible injuries. Daytime stomatal conductance rates were lowered by 14-54% in clone 5 and 9-74% in clone 2, depending on profile. The additional power-weighted analyses revealed that high peak concentrations and exposure shape were important for induction of visible injuries in both clones and reduction in stomatal conductance in clone 5, whereas growth reductions were rather related to total cumulative exposure. The results indicate that profile of ozone exposure, night-time stomatal conductance (24 h flux), and recovery time for defence and compensations reactions should not be ignored in plant response and ozone flux modelling.

  14. Physical and mechanical properties of plywood produced with 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU)-modified veneers of Betula sp. and Fagus sylvatica

    OpenAIRE

    Dieste, Andrés; Krause, Andreas; Bollmus, Susanne; Militz, Holger

    2008-01-01

    The dimensional stability and some mechanical properties were tested in plywood produced with veneers modified with 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU). The experimental design included Betula sp. and Fagus sylvatica impregnated with 0.8 M, 1.3 M, and 2.3 M DMDHEU. The plywood consisted of five veneers glued with a phenolic resin. Dimensional stability tests were conducted after 10 cycles of soaking/oven-drying to determine volume changes and anti swelling efficiency (ASE). The ...

  15. Aluminum uptake and migration from the soil compartment into Betula pendula for two different environments: a polluted and environmentally protected area of Poland

    OpenAIRE

    Frankowski, Marcin

    2015-01-01

    This paper presents the impact of soil contamination on aluminum (Al) concentrations in plant parts of Betula pendula and a possible way of migration and transformation of Al in the soil-root-stem-twig-leaf system. A new procedure of Al fractionation based on extraction in water phase was applied to obtain and measure the most available forms of Al in soils and B. pendula samples. In addition, total Al content was determined in biological samples and pseudo total Al content in soil samples co...

  16. Responses in the start of Betula (birch) pollen seasons to recent changes in spring temperatures across Europe

    Science.gov (United States)

    Emberlin, J.; Detandt, M.; Gehrig, R.; Jaeger, S.; Nolard, N.; Rantio-Lehtimäki, A.

    2002-07-01

    A shift in the timing of birch pollen seasons is important because it is well known to be a significant aeroallergen, especially in NW Europe where it is a notable cause of hay fever and pollen-related asthma. The research reported in this paper aims to investigate temporal patterns in the start dates of Betula (birch) pollen seasons at selected sites across Europe. In particular it investigates relationships between the changes in start dates and changes in spring temperatures over approximately the last 20 years. Daily birch pollen counts were used from Kevo, Turku, London, Brussels, Zurich and Vienna, for the core period from 1982 to 1999 and, in some cases, from 1970 to 2000. The sites represent a range of biogeographical situations from just within the Arctic Circle through to North West Maritime and Continental Europe. Pollen samples were taken with Hirst-type volumetric spore traps. Weather data were obtained from the sites nearest to the pollen traps. The timing of birch pollen seasons is known to depend mostly on a non-linear balance between the winter chilling required to break dormancy, and spring temperatures. Pollen start dates and monthly mean temperatures for January through to May were compiled to 5-year running means to examine trends. The start dates for the next 10 years were calculated from regression equations for each site, on the speculative basis that the current trends would continue. The analyses show regional contrasts. Kevo shows a marked trend towards cooler springs and later starts. If this continues the mean start date will become about 6 days later over the next 10 years. Turku exhibits cyclic patterns in start dates. A current trend towards earlier starts is expected to continue until 2007, followed by another fluctuation. London, Brussels, Zurich and Vienna show very similar patterns in the trends towards earlier start dates. If the trend continues the mean start dates at these sites will advance by about 6 days over the next 10

  17. Geochronology of Betula extensions in pollen diagrams of Alpine Late-glacial lake deposits: A case study of the Late-glacial deposits of the Gasserplatz soil archives (Vorarlberg, Austria)

    NARCIS (Netherlands)

    J.M. van Mourik; R.T. Slotboom; J. van der Plicht; H.J. Streurman; W.J. Hoek; W.J. Kuijper; L.W.S. de Graaff

    2013-01-01

    Pollen diagrams of Alpine Late-glacial calcareous lake deposits show several extensions of Betula. The geochronology of these extensions cannot be based on radiocarbon dating due to reservoir effects of such lakes on the radiocarbon ages. A robust geochronology can be based on the oxygen isotope str

  18. Geochronology of Betula extensions in pollen diagrams of Alpine Late-glacial lake deposits: A case study of the Late-Glacial deposits of the Gasserplatz soil archives (Vorarlberg, Austria)

    NARCIS (Netherlands)

    van Mourik, J.M.; Slotboom, R.T.; van der Plicht, J.; Streurman, H.J.; Kuijper, W.J.; Hoek, W.Z.; de Graaff, L.W.S.

    2013-01-01

    Pollen diagrams of Alpine Late-glacial calcareous lake deposits show several extensions of Betula. The geochronology of these extensions cannot be based on radiocarbon dating due to reservoir effects of such lakes on the radiocarbon ages. A robust geochronology can be based on the oxygen isotope str

  19. Geochronology of Betula extensions in pollen diagrams of Alpine Late-glacial lake deposits : A case study of the Late-glacial deposits of the Gasserplatz soil archives (Vorarlberg, Austria)

    NARCIS (Netherlands)

    van Mourik, Jan M.; Slotboom, Ruud T.; van der Plicht, Johannes; Streurman, Harm Jan; Kuijper, Wim J.; Hoek, Wim Z.; de Graaff, Leo W. S.

    2013-01-01

    Pollen diagrams of Alpine Late-glacial calcareous lake deposits show several extensions of Betula. The geochronology of these extensions cannot be based on radiocarbon dating due to reservoir effects of such lakes on the radiocarbon ages. A robust geochronology can be based on the oxygen isotope str

  20. Ectomycorrhizas in vitro between Tricholoma matsutake, a basidiomycete that associates with Pinaceae, and Betula platyphylla var. japonica, an early-successional birch species, in cool-temperate forests.

    Science.gov (United States)

    Murata, Hitoshi; Yamada, Akiyoshi; Maruyama, Tsuyoshi; Neda, Hitoshi

    2015-04-01

    Tricholoma matsutake is an ectomycorrhizal basidiomycete that associates with Pinaceae in the Northern Hemisphere and produces prized "matsutake" mushrooms. We questioned whether the symbiont could associate with a birch that is an early-successional species in boreal, cool-temperate, or subalpine forests. In the present study, we demonstrated that T. matsutake can form typical ectomycorrhizas with Betula platyphylla var. japonica; the associations included a Hartig net and a thin but distinct fungal sheath, as well as the rhizospheric mycelial aggregate "shiro" that is required for fruiting in nature. The in vitro shiro also emitted a characteristic aroma. This is the first report of an ectomycorrhizal formation between T. matsutake and a deciduous broad-leaved tree in the boreal or cool-temperate zones that T. matsutake naturally inhabits. PMID:25236465

  1. Comparison of {sup 226}Ra nuclide from soil by three woody species Betula pendula, Sambucus nigra and Alnus glutinosa during the vegetation period

    Energy Technology Data Exchange (ETDEWEB)

    Soudek, Petr; Petrova, Sarka; Benesova, Dagmar [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR and Crop Research Institute, Rozvojova 263, 165 02 Prague 6 (Czech Republic); Tykva, Richard [Department of Radioisotopes, Institute of Organic Chemistry and Biochemistry AS CR, Flemingovo nam. 2, 166 10 Prague 6 (Czech Republic); Vankova, Radomira [Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany AS CR, Rozvojova 263, 165 02 Prague 6 (Czech Republic); Vanek, Tomas [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR and Crop Research Institute, Rozvojova 263, 165 02 Prague 6 (Czech Republic)], E-mail: vanek@ueb.cas.cz

    2007-09-15

    The uptake of {sup 226}Ra from the contaminated soil was compared in three woody species: alder (Alnus glutinosa), birch (Betula pendula) and elder (Sambucus nigra). The {sup 226}Ra activities increased during the vegetation periods (in 2003, 2004 and 2005) both in the leaves and flowers + seeds. The highest accumulation was found in birch, reaching 0.41 Bq/g DW in the leaves (at the end of the vegetation period in 2003). The lowest {sup 226}Ra accumulation was determined in alder. The extent of {sup 226}Ra accumulation in the leaves of woody species demonstrates that these pioneer woody species can be used as remediation alternative to the use of herbs, provided that the removal of fallen leaves could be achieved in the end of vegetation period.

  2. Validation of Two Names Betula jiulungensis (Betulaceae) and Rubia ovatifolia (Rubiaceae)%九龙桦(桦木科)与卵叶茜草(茜草科)名称的合格发表

    Institute of Scientific and Technical Information of China (English)

    林祁

    2007-01-01

    由于同时指定两号标本为模式,桦木科(Betulaceae)的九龙桦(Betula jiulungensis Hu exP.C.Li)和茜草科(Rubiaceae)的卵叶茜草(Rubia ovatifolia Z.Y.Zhang)是不合格发表的名称.现通过分别指定主模式,对九龙桦和卵叶茜草的名称作合格发表.

  3. The Evaluation of CP-001 (a Standardized Herbal Mixture of Houttuynia cordata, Rehmannia glutinosa, Betula platyphylla, and Rubus coreanus for Cytochrome P450-Related Herb-Drug Interactions

    Directory of Open Access Journals (Sweden)

    Hye Hyun Yoo

    2013-01-01

    Full Text Available In the present study, the effect of CP-001, a standardized herbal mixture of Houttuynia cordata, Rehmannia glutinosa, Betula platyphylla, and Rubus coreanus, on cytochrome P450 (CYP enzyme-mediated drug metabolism was investigated in vitro to evaluate the potential for herb-drug interactions. CP-001 was tested at concentrations of 1, 3, 10, 30, and 100 μg/mL. A CYP-specific substrate mixture was incubated with CP-001 in human liver microsomes, and the metabolites generated by each CYP-specific metabolic reaction were measured by liquid chromatography-tandem mass spectrometry. CP-001 seemed to slightly inhibit some CYP isozymes, but the IC50 values for all CYP isozymes were greater than 100 μg/mL. Furthermore, CP-001 did not exhibit time-dependent CYP inhibitory activities, indicating that it does not act as a mechanism-based inactivator of CYP enzymes. In conclusion, the effects of CP-001 on CYP isozyme activities were negligible at the concentrations tested. Therefore, the likelihood of herbal mixture-drug interaction is considered minimal.

  4. The effect of exogenous sugar solution and high concentration of CO2 on the contents of sugar and protein of Betula platyphylla leaves

    Institute of Scientific and Technical Information of China (English)

    ZHOUYu-mei; YANGChuan-ping; WANGShu-juan; WUYue-liang; WANGWen-zhang

    2003-01-01

    The content of total sugar,sucrose,fructose and protein in the leaves of 3-yr.-old Betula platyphylla was measured after the treatment by three exogenous sugar solutions(sucrose,fructose,glucose) and three high concentrations of CO2(700,1400,2100μL·L-1) for about a month in 1998.The results showed that spraying three exogenous sugar solutions increased markedly the content of sugar and protein of leaves under 700μL·L-1 and 1400μL·L-1 CO2.The effect of spraying exogenous sucrose solution was the best among the three exogenous sugars.The treatment of spraying exogenous sugar solution and 2100μL·L-1 CO2 constrained the accumulation of total sugar and protein of leaves.There was no difference in protein content of leaves when spraying glucose and fructose solutions under 700μL·L-1 and 1400μL·L-1 CO2.The treatrnent of 2100μL·L-1 CO2 concentration significantly increased the contents of total sugar,sucrose,fructose,and protein of leaves compared with that of the 700μL·L-1 and 1400μL·L-1 CO2 except the plants spraying fructose solution.there was positive correlation between the content of sugar of leaves and CO2 concentration when spraying same exogenous sugar solution.

  5. Metal resistance in populations of red maple (Acer rubrum L.) and white birch (Betula papyrifera Marsh.) from a metal-contaminated region and neighbouring non-contaminated regions

    International Nuclear Information System (INIS)

    Metal resistance in populations of Acer rubrum and Betula papyrifera in the industrially contaminated region of Sudbury, Ontario, was compared with resistance in populations from neighbouring uncontaminated regions. In two one-season experiments, seedlings were grown outdoors on contaminated (mainly Cu, Ni) and uncontaminated substrates. Sudbury populations of both species responded less to contamination than populations from uncontaminated regions. In A. rubrum this difference was small. For both species, Sudbury plants were smaller when grown on uncontaminated substrate. B. papyrifera from Sudbury grew better on contaminated substrate than the other populations. There is indication of variation in metal resistance within the populations from the non-contaminated regions. The data shows that trees may develop adaptive resistance to heavy metals, but the low degree of resistance indicates that the development of such resistances are slower than observed for herbaceous species with shorter generation times. - Highlights: ► Metal resistance in trees from an industrially contaminated region was investigated. ► Both red maple and white birch have developed some degree of resistance. ► There is indication of a cost for resistance. ► Populations from non-contaminated regions show variation in response to contamination. - Adaptive metal resistance can also develop in trees with long generation times, but the degree of resistance is lower than for herbaceous species from the same region.

  6. Aluminum uptake and migration from the soil compartment into Betula pendula for two different environments: a polluted and environmentally protected area of Poland.

    Science.gov (United States)

    Frankowski, Marcin

    2016-01-01

    This paper presents the impact of soil contamination on aluminum (Al) concentrations in plant parts of Betula pendula and a possible way of migration and transformation of Al in the soil-root-stem-twig-leaf system. A new procedure of Al fractionation based on extraction in water phase was applied to obtain and measure the most available forms of Al in soils and B. pendula samples. In addition, total Al content was determined in biological samples and pseudo total Al content in soil samples collected under plant saplings, using atomic absorption spectrometry with flame atomization. A number of relations concerning the occurrence of Al and Ca in soils and plant parts of B. pendula (tap roots, lateral roots, stem, twigs, and leaves) were observed. Based on the research findings, the mechanism of Al migration from soil to the leaves of B. pendula can be presented. It was found that aluminum uptake may be limited in roots by high calcium concentration. The application of a new procedure based on the simple sequential extraction of water-soluble fractions (the most available and exchangeable fractions of Al) can be used as an effective tool for the estimation of aluminum toxicity in soils and plants. PMID:26370811

  7. Soil metal concentrations and productivity of Betula populifolia (gray birch) as measured by field spectrometry and incremental annual growth in an abandoned urban Brownfield in New Jersey

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, Frank J. [Urban Forestry Program, Department of Ecology, Evolution and Natural Resources, Rutgers, State University, 14 College Farm Road, New Brunswick, NJ 08901-8551 (United States); Pechmann, Ildiko [Department of Biological Sciences, Rutgers, State University, 113 University Avenue, Newark, NJ 07102 (United States)], E-mail: pildiko@andromeda.rutgers.edu; Bogden, John D. [Department of Preventive Medicine and Community Health, University of Medicine and Dentistry of New Jersey - N. J. Medical School, P.O. Box 1709, Newark, NJ 07101-1709 (United States); Grabosky, Jason [Urban Forestry Program, Department of Ecology, Evolution and Natural Resources, Rutgers, State University, 14 College Farm Road, New Brunswick, NJ 08901-8551 (United States); Weis, Peddrick [Department of Radiology, University of Medicine and Dentistry of New Jersey - N. J. Medical School, P.O. Box 1709, Newark, NJ 07101-1709 (United States)

    2008-12-15

    A forested brownfield within Liberty State Park, Jersey City, New Jersey, USA, has soils with arsenic, chromium, lead, zinc and vanadium at concentrations above those considered ambient for the area. Using both satellite imagery and field spectral measurements, this study examines plant productivity at the assemblage and individual specimen level. Longer term growth trends (basal area increase in tree cores) were also studied. Leaf chlorophyll content within the hardwood assemblage showed a threshold model for metal tolerance, decreasing significantly beyond a soil total metal load (TML) of 3.0. Biomass production (calculated with RG - Red/Green Ratio Index) in Betula populifolia (gray birch), the co-dominant tree species, had an inverse relationship with the Zn concentration in leaf tissue during the growing season. Growth of B. populifolia exhibited a significant relationship with TML. Assemblage level NDVI and individual tree NDVI also had significant decreases with increasing TML. Ecosystem function measured as plant production is impaired at a critical soil metal load. - Ecosystem function as measured by plant production is impaired at a critical soil metal load (TML above 3) in northern hardwood assemblages growing in a metal-contaminated brownfield.

  8. Soil metal concentrations and productivity of Betula populifolia (gray birch) as measured by field spectrometry and incremental annual growth in an abandoned urban Brownfield in New Jersey

    International Nuclear Information System (INIS)

    A forested brownfield within Liberty State Park, Jersey City, New Jersey, USA, has soils with arsenic, chromium, lead, zinc and vanadium at concentrations above those considered ambient for the area. Using both satellite imagery and field spectral measurements, this study examines plant productivity at the assemblage and individual specimen level. Longer term growth trends (basal area increase in tree cores) were also studied. Leaf chlorophyll content within the hardwood assemblage showed a threshold model for metal tolerance, decreasing significantly beyond a soil total metal load (TML) of 3.0. Biomass production (calculated with RG - Red/Green Ratio Index) in Betula populifolia (gray birch), the co-dominant tree species, had an inverse relationship with the Zn concentration in leaf tissue during the growing season. Growth of B. populifolia exhibited a significant relationship with TML. Assemblage level NDVI and individual tree NDVI also had significant decreases with increasing TML. Ecosystem function measured as plant production is impaired at a critical soil metal load. - Ecosystem function as measured by plant production is impaired at a critical soil metal load (TML above 3) in northern hardwood assemblages growing in a metal-contaminated brownfield

  9. INHIBITORY EFFECTS OF POLYPHENOLIC EXTRACTS OF BETULA PENDULA, SALIVA HYDRANGEA AND CRATAEGUS CURVISEPALA, AS WELL AS VITAMIN C, ON THE EXTENT OF GLYCOSYLATION OF ALBUMIN, INSULIN AND HEMOGLOBIN

    Directory of Open Access Journals (Sweden)

    SEDIGHEH ASGARY

    2003-09-01

    Full Text Available Introduction: Diabetes is one of the most common endocrine diseases spreading rapidly in the world. Diabetes complications are classified to acute and chronic. Non-enzymatic glycosylation of all body proteins, such as hemoglobin, albumin is the main cause of pathogenesis in chronic complications of diabetes. As glycosylation reaction of proteins is an oxidative reaction it seems that antioxidants, such as vitamin C, inhibit the reaction and, therefore, chronic complications of diabetes. In the present study inhibitory effects of polyphenolic extracts of Betula pendula, Saliva hydrangea and Crataegus curvisepala, as well as vitamin C, on the extent of glycosylation of albumin, insulin and hemoglobin was investigated. Methods: Polyphenolic extracts of the mentioned plants were prepared in three different concentrations; 3.6, 1.8, and 0.9 mg/ml also vitamin C solutions were prepared in 5 concentrations: 0.5, 5, 10, 50 and 500 µg/ml. Results: The highest extent of glycosylation inhibition of albumin and insulin was due to S.hydrangea by 100% and 97% respectively, and that of hemoglobin was due to a.pendula, by 80%. Vitamin C in its highest concentration inhibit glycosylation of insulin, albumin and hemoglobin by 100%, 93%, and 58% respectively (P < 0.05. Discussion: Based on the findings, it seems that these plants prevent chronic complications of diabetes.

  10. Effects of light intensity and duration on leaf hydraulic conductance and distribution of resistance in shoots of silver birch (Betula pendula).

    Science.gov (United States)

    Sellin, Arne; Ounapuu, Eele; Kupper, Priit

    2008-11-01

    Variation in leaf hydraulic conductance (K(L)) and distribution of resistance in response to light intensity and duration were examined in shoots of silver birch (Betula pendula Roth). K(L) was determined on detached shoots using the evaporative flux method (transpiration was measured with a porometer and water potential drop with a pressure chamber). Although K(L) depended on light duration per se, its dynamics was largely determined by leaf temperature (T(L)). Both upper-crown leaves and branches developed in well-illuminated environment exhibited higher hydraulic efficiency compared with the lower crown, accounting for vertical trends of apparent soil-to-leaf hydraulic conductance in canopy of silver birch revealed in our previous studies. K(L) varied significantly with light intensity, the highest values for both shade and sun foliage were recorded at photosynthetic photon flux density of 330 micromol m(-2) s(-1). Light responses of K(L) were associated evidently with an irradiance-mediated effect on extravascular tissues involving regulation of cell membrane aquaporins. Effects of irradiance on K(L) resulted in changes of Psi(L), bringing about considerable alteration in partitioning of the resistance between leaves and branch (leafless shoot stem): the contribution of leaves to the shoot total resistance decreased from 94% at -1.0 MPa to 75% at -0.2 MPa. Treatment with HgCl2 decreased hydraulic conductance of both leaves and branches, implying that condition of bordered pit membranes or shoot living tissues may be involved in responses of xylem conductance to Hg2+. PMID:18513374

  11. The effect of tree architecture on conduit diameter and frequency from small distal roots to branch tips in Betula pendula, Picea abies and Pinus sylvestris.

    Science.gov (United States)

    Lintunen, Anna; Kalliokoski, Tuomo

    2010-11-01

    We studied the effect of tree architecture on xylem anatomy in three Betula pendula Roth., three Picea abies (L.) H. Karst. and three Pinus sylvestris (L.) trees (mean age 35 years). First, the analysis of conduit anatomy in different tree parts showed that conduits tapered and their frequency increased from roots (≥ 2 mm) to stem, from stem to branches and further to leaf petioles in B. pendula. Conduit anatomy in lateral and main roots, as well as lateral and main branches, significantly differed from each other in all the studied species. The increase in conduit diameter and decrease in frequency from the pith to the bark were clear aboveground, but variable patterns were observed belowground. In the leaf petioles of B. pendula, conduit diameter increased and conduit frequency decreased with increasing individual leaf area. Second, the results concerning the scaling of conduit diameter were compared with the predictions of the general vascular scaling model (WBE model) and Murray's law. The scaling parameter values at the tree level corresponded with the predictions of the WBE model in all the studied trees except for one tree of both conifer species. However, the scaling parameter values changed from one tree compartment to another rather than remaining uniform inside a tree, as assumed by the WBE model. The assumptions of the WBE model of a constant conductivity ratio, constant tapering and an unchanged total number of conduits were not fulfilled. When the conductivity ratio and relative tapering were plotted together, the results aboveground corresponded quite well with Murray's law: the conductivity ratio increased when relative tapering decreased. Our results support the theory that trees adjust both their macro- and microstructure to maximize their water transport efficiency, but also to prevent embolism and ensure mechanical safety. PMID:21030407

  12. [Allelopathic effects of the humus soils from Betula platyphylla and Quercus liaotungensis pure plantations on 9 kinds of common shrubs and herbs].

    Science.gov (United States)

    Huang, Liang-Jia; Liu, Zeng-wen; Zhu, Bo-Chao; Bing, Yuan-Hao; Zhang, Xiao-Xi; Lü, Chen

    2014-06-01

    The humus soils were collected from Betula platyphylla and Quercus liaotungensis pure plantations and woodless land separately where the site conditions were basically the same, and taken as medium for potting culture test of 9 kinds of shrubs or herbs in plastic greenhouse to assess the allelopathic effects of humus soils of pure plantations on shrubs or herbs. Humus soils from B. platyphylla plantation significantly inhibited the seed germinations of Medicago sativa and Melilotus officinalis, decreased the catalase (CAT) activity of M. officinalis, Coronilla varia, M. sativa and Lespedeza davurica, and improved malondialdehyde (MDA) contents in seedlings of Caragana kor-shinskii, C. varia and Astragalus adsurgens. The biomass growths of C. varia, Amorpha fruticosa, M. sativa, M. officinalis and A. adsurgens in humus soils from B. platyphylla plantation were significantly decreased by 48.2%, 45.1%, 44.3%, 37.3% and 36.0%, respectively. In addition, humus soil of Q. liaotungensis plantation significantly decreased the germination rates of M. sativa and A. adsurgens, the chlorophyll contents of Vicia villosa, A. fruticosa and M. sativa, and improved malondialdehyde (MDA) contents in seedlings of Lespedeza davurica, Caragana korshinskii, M. officinalis and A. adsurgens. The biomass growths of A. adsurgens, M. sativa, M. officinalis and A. fruticosa were significantly decreased by 52.6% , 43.8%, 35.5% and 34.6%, respective- ly. B. platyphylla plantation humus soil had obvious inhibition effects on M. sativa, M. officinalis and A. fruticosa, while Q. liaotungensis plantation humus soil had obvious inhibition effects on M. sativa, A. adsurgens and A. fruticosa. PMID:25223017

  13. Physiological responses of birch (Betula pendula) to ozone: a comparison between open-soil-grown trees exposed for six growing seasons and potted seedlings exposed for one season.

    Science.gov (United States)

    Oksanen, Elina

    2003-06-01

    Physiological responses of 4-year-old potted saplings of an O3-tolerant clone of Betula pendula Roth to short-term ozone (O3) exposure (one growing season) were compared with those of 6-year-old open-soil-grown trees of the same clone fumigated with O3 for six growing seasons. In the 2001 growing season, both groups of plants were exposed to ambient (control) and 1.6x ambient (elevated) O3 concentration under similar microclimatic conditions in a free air O3 exposure facility. Growth, net photosynthesis, stomatal conductance, stomatal density, visible foliar injury, starch and nutrient concentrations, bud formation and differences in O3 responses between lower, middle and upper sections of the canopy were determined. The potted saplings were unaffected by elevated O3 concentration, whereas the open-soil-grown trees showed a 3-38% reduction in shoot growth, a 22% reduction in number of overwintering buds, a 26-65% decrease in autumnal net photosynthesis, 30% and 20-23% reductions in starch and nitrogen concentrations of senescing leaves, respectively, and disturbances in stomatal conductance. The greater O3 sensitivity of open-soil-grown trees compared with potted saplings was a result of senescence-related physiological factors. First, a lower net photosynthesis to stomatal conductance ratio in open-soil-grown trees at the end of the season promoted O3 uptake and decreased photosynthetic gain, leading to the onset of visible foliar injuries. Second, decreased carbohydrate reserves may have resulted in deleterious carry-over effects arising from the reduced formation of over-wintering buds. Finally, the leaf-level O3 load was higher for open-soil-grown trees than for potted saplings because of slower leaf senescence in the trees. Thus, O3 sensitivity in European white birch increases with increasing exposure time and tree size. PMID:12750053

  14. 天然杨-桦次生林空间结构特征%Spatial structural characteristics of natural Populus davidiana - Betula platyphylla secondary forest

    Institute of Scientific and Technical Information of China (English)

    邵芳丽; 余新晓; 宋思铭; 赵阳

    2011-01-01

    运用直径分布和空间结构参数混交度、大小比数和角尺度,分析了木兰围场4 hm2天然杨-桦次生林的空间结构.结果表明:天然杨-桦次生林林分径级结构呈反“J”型曲线;林分平均混交度为0.4,其弱度和零度混交比例达51.6%,山杨、白桦的平均混交度分别为0.25和0.39;以胸径、树高为参数的大小比数基本一致,显示山杨、白桦处于亚优势向中庸的过渡状态;林分水平分布格局与树木起测直径密切相关,当起测直径为1 cm≤DBH<6 cm时,林分呈聚集分布,当起测直径DBH≥6 cm时,林分呈随机分布.%This paper analyzed the spatial structural characteristics of natural Populus davidiana -Betula platyphylla secondary forest in a 4 hm2 plot of Mulan Paddock, based on the diameter distribution and the spatial structure parameters mingling degree, neighborhood comparison, and angle index. In the forest, the diameter distribution of the stands presented as an inverse ' J' curve, the average mingling degree was 0. 4, with the individuals at weak and zero mingling degree reached 51. 6% , and the average mingling degree of P. Davidiana and B. Platyphylla was 0. 25 and 0. 39, respectively. The neighborhood comparison based on the diameter at breast height ( DBH) and tree height was almost the same, suggesting that the P. Davidiana and B. Platyphylla were in the transition state from subdominant to middle. The horizontal distribution pattern had a close relation to the minimum measured DBH, being clustered when the DBH was ≥1 cm and <6 cm, and random when the DBH was ≥6 cm.

  15. Elevated CO{sub 2} and limited nitrogen nutrition can restrict excitation energy dissipation in photosystem 2 of Japanese white birch (Betula platyphylla var. japonica) leaves

    Energy Technology Data Exchange (ETDEWEB)

    Kitao, M.; Tobita, H.; Maruyama, Y. [Forestry and Forest Products Research Inst., Hokkaido Research Center, Sapporo (Japan); Koike, T. [Hokkaido Univ., Hokkaido Univ. Forests, Sapporo (Japan)

    2005-09-01

    Elevated atmospheric C0{sub 2} concentration [C0{sub 2}] and different levels of nitrogen (N) nutrition can influence the amount of excess excitation energy in photosystem (PS) II and related photosynthetic properties. The interactive effect of two [C0{sub 2}] levels (ambient: 360 {mu}M M{sub -1} and elevated: 720 {mu}M{sub -1}) and two N levels (high: 700 mg N plant{sub -1} and low: 100 mg N plant{sub -1}) on these properties was examined in seedlings of Japanese white birch (Betula platyphylla var. japonica) using simultaneous measurements of gas exchange and chlorophyll fluorescence. Photosynthetic acclimation to elevated [C0{sub 2}], as indicated by a decline in carboxylation efficiency (CE), was observed in plants Brown at elevated [C02] especially under low N. Elevated [C0{sub 2}] resulted in a decrease in area-based leaf N content (N{sub area}) irrespective of N treatment. The adverse effect of elevated [C0{sub 2}] and low N on CE may have been exacerbated by a greater accumulation of leaf sugar and starch contents in these plants leading to a lower electron transport rate (ETR). While these plants also showed higher non-photochemical quenching (Nq{sub p}) that could offset the reduction in energy dissipation through ETR to some extent, they still have a higher risk of photoinhibition from excessive excitation energy in PSII as indicated by a decrease in photochemical quenching (q{sub p}). However, chronic photoinhibition was not observed in plant Grown at elevated [C0{sub 2}] and low N because they showed no difference in F{sub v}F{sub m} (the maximum photochemical efficiency of PS II) from those Brown at ambient [C0{sub 2}] and low N after an overnight dark adaptation. High levels of Nq{sub p} in plants Brown at elevated [C0{sub 2}] and low N reflect a near saturation of thermal energy dissipation. This impaired capacity of photoprotection would render these plants more vulnerable to photoinhibition in the event of additional environmental stresses such as

  16. STUDY ON THOUSAND-SEED WEIGHT,LONGEVITY AND VITALITY OF SEEDS OF BETULA LUMINIFERA%光皮桦种子千粒重、寿命及生命力研究

    Institute of Scientific and Technical Information of China (English)

    祝小科; 朱守谦

    2003-01-01

    The thousand-seed weight, germination rate and vitality of seeds for Betula luminifera were studied. The results showed that the thousand-seed weight was different in various habitats, and varied with the age and the part of crown and fruit. The seed had a longevity of 32—37 days in general and with a characteristic of the rapid germination. The seed had a high germination rate during the early stage or perk stage of seed dispersal, and a lower germination rate during the end stage. The germination rate and vitality of mature seed reduced with the increase of the storing time, the change in seed ger-mination was significantly different at the various ages and habitats.

  17. Change in ATP-binding cassette B1/19, glutamine synthetase and alcohol dehydrogenase gene expression during root elongation in Betula pendula Roth and Alnus glutinosa L. Gaertn in response to leachate and leonardite humic substances.

    Science.gov (United States)

    Tahiri, Abdelghani; Delporte, Fabienne; Muhovski, Yordan; Ongena, Marc; Thonart, Philippe; Druart, Philippe

    2016-01-01

    Humic substances (HS) are complex and heterogeneous compounds of humified organic matter resulting from the chemical and microbiological decomposition of organic residues. HS have a positive effect on plant growth and development by improving soil structure and fertility. They have long been recognized as plant growth-promoting substances, particularly with regard to influencing nutrient uptake, root growth and architecture. The biochemical and molecular mechanisms through which HS influence plant physiology are not well understood. This study evaluated the bioactivity of landfill leachate and leonardite HS on alder (Alnus glutinosa L. Gaertn) and birch (Betula pendula Roth) during root elongation in vitro. Changes in root development were studied in relation to auxin, carbon and nitrogen metabolisms, as well as to the stress adaptive response. The cDNA fragments of putative genes encoding two ATP-binding cassette (ABC) transporters (ABCB1 and ABCB19) belonging to the B subfamily of plant ABC auxin transporters were cloned and sequenced. Molecular data indicate that HS and their humic acid (HA) fractions induce root growth by influencing polar auxin transport (PAT), as illustrated by the modulation of the ABCB transporter transcript levels (ABCB1 and ABCB19). There were also changes in alcohol dehydrogenase (ADH) and glutamine synthetase (GS) gene transcript levels in response to HS exposure. These findings confirmed that humic matter affects plant growth and development through various metabolic pathways, including hormonal, carbon and nitrogen metabolisms and stress response or signalization. PMID:26595095

  18. Preliminary Study of Predominant Factors on Chromosome Doubling ofBetula alnoides%西南桦染色体加倍的影响因子初步研究

    Institute of Scientific and Technical Information of China (English)

    陈荣; 朱昌叁; 庞正轰

    2014-01-01

    In this paper, a method for chromosome doubling ofBetula alnoideswas developed. Terminal buds from aseptic germination ofB. alnoides were used as explants, effect factors on chromosome doubling ofB. alnoides were discussed, such as concentration of colchicine, co-culture time of colchicine, preculture time. The results showed that the concentration of colchicine was better to be 120 mg·L-1 for chromosome doubling ofB. alnoides, and maximum chimaera number would be obtained in the regermination plantlet ofB. alnoides, after preculture without colchicine for 10 d and then co-culture with colchicine for 15 d.%以西南桦种子无菌萌发小苗的顶芽为外植体,探讨秋水仙素的浓度、处理时间及预培养时间对西南桦染色体加倍的影响,初步建立西南桦染色体加倍的方法。结果表明,使西南桦染色体加倍的秋水仙素浓度以120 mg·L-1为宜;在秋水仙素加倍处理前,预培养10 d后再加倍15 d效果较好,此时得到的西南桦嵌合体较多。

  19. Spatial Pattern Analysis of Individuals in Different Age-classes of Betula platyphylla in Huoshan Mountain of Shanxi Province%山西霍山白桦种群不同龄级立木的点格局分析

    Institute of Scientific and Technical Information of China (English)

    何艳华; 闫明; 武丽君; 张直峰; 毕润成

    2011-01-01

    Betula platyphylla is a pioneer plant and is distributed intensively in Huoshan mountain. One 50 m x 50 m quadrat was established in Qiliyu from which we recorded the DBH of each individual and the spatial points of all individuals were mapped. The data were analyzed by point pattern analysis. All individuals were divided into four DBH classes; DBH I (DBH≤ 7 cm);DBH Ⅱ (7 cm 21 cm).The results of this study showed; (1) The densities of four age-classes varied in the order: age-class n >age-class Ⅲ >age-class Ⅰ>age-class Ⅳ. The middle age-classes Ⅱ and Ⅲ had many more individuals than age-classes I and Ⅳ, which indicated that the population was currently in decline. (2) The individuals of all age-classes focused on clumping distribution in space, except the age-class Ⅰ. The feature of clumping distribution became more significant with increasing age. (3) The relationships between individuals in different age-classes were significantly correlated with each other on a small scale,but became non-significant with increasing scale,except for age-classes I and n ,age-classes Ⅱ and Ⅲ,and age-classes n and Ⅳ.%以山西霍山地区的先锋树种之一白桦( Betula platyphylla)为研究对象,在霍山七里峪林场典型地段设置一个50 m×50 m的样方,应用点格局分析方法对其不同龄级(Ⅰ级、Ⅱ级、Ⅲ级和Ⅳ级)个体的分布格局及相互关系进行了研究.结果表明:(1)白桦种群不同龄级的个体间密度也不相同,中间龄级Ⅱ级(7 cm< DBH≤14 cm)和Ⅲ级(14 cm <DBH≤21 cm)的密度较大,幼龄和老龄个体密度小,年龄结构为衰退型;(2)除Ⅰ级(DBH≤7 cm)外,其余3个龄级集群分布特征比较明显,且随着龄级的增加,集群特征有更明显的趋势;(3)除Ⅰ级和Ⅱ级、Ⅱ级和Ⅲ级、Ⅱ级和Ⅳ级(DBH >21 cm)之外,其余龄级间基本都是小尺度下负关联,并随尺度的增大关联性逐渐变得不显著.

  20. Carbon gain and bud physiology in Populus tremuloides and Betula papyrifera grown under long-term exposure to elevated concentrations of CO{sub 2} and O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Riikonen, J. [Kuopio Univ., Kuopio (Finland). Dept. of Ecology and Environmental Science; Kets, K.; Sober, A. [Tartu Univ., Tartu (Estonia). Inst. of Botany and Ecology; Darbah, J.; Karnosky, D.F. [Michigan Technical Univ., Houghton, MI (United States). School of Forest Resources and Environmental Science; Oksanen, E. [Joensuu Univ., Joensuu (Finland). Faculty of Biosciences; Vapaavuori, E. [Finnish Forest Research Inst., Suonenjoki (Finland). Suonenjoki Research Inst.; Kubiske, M.E.; Nelson, N. [USDA Forest Service, Rhinelander, WI (United States). Forestry Sciences Laboratory

    2008-02-15

    Elevated carbon dioxide (CO{sub 2}) enhances photosynthesis by increasing carboxylation rates and decreasing the rate of photorespiration. While elevated CO{sub 2} has the potential to increase frost hardiness in trees by increasing bud size and concentrations of cryoprotective soluble sugars in overwintering organs, little is known about the effects of elevated CO{sub 2} on late-season photosynthesis. This study examined 3 trembling aspen (Populus tremuloides) clones and 3 paper birch (Betula papyrifera) grown at a site with elevated CO{sub 2} and ozone (O{sub 3}) applied singly and in combination. Gas exchange was studied throughout the eighth growing season. The study also examined specific leaf area and size in September and final size, carbohydrate, carbon (C), nitrogen (N) and water concentrations in November. The timing of leaf abscission was also studied, as well as bud burst and the development of leaf area index the following Spring. Results of the study showed that net photosynthesis was enhanced by between 49 and 73 per cent with elevated levels of CO{sub 2}, and decreased by between 13 and 30 per cent with elevated O{sub 3}. Elevated CO{sub 2} delayed leaf abscission and increased the ratio of monosaccharides in aspen buds. Total carbon concentrations in overwintering buds were unaffected by the treatments. It was concluded that elevated CO{sub 2} ameliorated the effects of elevated O{sub 2}, but had the potential to alter C metabolism of overwintering buds. 50 refs., 5 tabs., 6 figs.

  1. 西南桦苗木猝倒病生防菌的筛选及鉴定研究%Isolation and Identification of Damping-off Antagonist of Betula alnoides Seedlings

    Institute of Scientific and Technical Information of China (English)

    李娅; 朱潇逸; 景跃波; 庞静; 赵永红; 李翠萍; 曾郁珉; 伍建榕

    2013-01-01

    The tissue isolation and dilution-plate were used on healthy seedlings tissue , rhizosphere soil and coffee shell composting matrix for isolating antagonists of damping-off disease of Betula alnoides seedlings;and the isolated strains were identified through molecular method .The confront culture was conducted between 17 isolated strains and the pathogens Fusarium oxysporum and Fusarium solani to screen for antagonists .The results indicated that , the fungus strains 5#, 7#and bacteria BJ and JC1showed promising inhibition effects on two pathogens .The inhibi-tion rates of fungus strains 5# and 7# to the pathogens were 91.30 % and 90.12 % respectively , two bacteria strains had the inhibition belts of 0.4 cm and 0.5 cm, with the inhibition rates of 80.40%and 78.60% respec-tively , and BJ showed the better inhibition effect .The inhibition effects of two isolated fungal strains were better than bacterial strains .%采用组织分离法和稀释平板法对西南桦猝倒病发生区健康苗木组织、根际土壤及咖啡壳堆肥化基质进行菌种分离和分子鉴定。将分离获得的17株菌株与西南桦苗木猝倒病病原菌尖孢镰刀菌和腐皮镰刀菌进行平板对峙实验,筛选病原拮抗菌。结果表明,筛选出的真菌5#、7#及细菌 BJ、 JC1对西南桦苗木猝倒病原菌尖孢镰刀菌和腐皮镰刀菌具有较强抑制效果。其中真菌5#和7#的抑菌率分别为91.30%和90.12%;细菌BJ和JC1抑菌带较宽,对峙4天分别达0.4 cm和0.5 cm,抑菌率分别为80.4%和78.6%,且BJ抑菌效果更好;真菌与细菌比较,拮抗真菌5#和7#比拮抗细菌BJ和JC1抑制热区西南桦苗木猝倒病菌效果更好。通过对峙实验筛选出的5#、7#、 BJ和JC1拮抗菌,对热区防治苗木猝倒病及生防制剂的开发应用具有参考价值。

  2. Accumulation of Triterpenoids in Betula platyphylla Suspension Culture Induced by a Fungal Elicitor%真菌诱导子促进白桦悬浮细胞三萜的积累

    Institute of Scientific and Technical Information of China (English)

    翟俏丽; 范桂枝; 詹亚光

    2011-01-01

    Endophytic fungus of Phomopsis isolated from birch(Betula platyphylla) bark can be used as an elicitor to induce accumulation of triterpenoids in birch cell suspension culture. The change of dry weight and triterpenoids content of birch suspension cell were investigated at early growth phase, exponential growth phase and late growth phase after a fungal elicitor of 40, 100, and 400 (xg-mL"' concentration was added to birch suspension cells. Results showed that different induction schemes all promoted accumulation of triterpenoids, while the treatments reduced the dry weight of birch cells. Suspension cells at exponential growth phase were most easy to be induced, and 40 ng-mL"' fungal elicitor enhanced the triterpenoids content to 29. 47 mg-g"1, increasing by 789$j than that of the control. We investigated changes in pH and conductivity of the medium, and the activity of phenylalanine ammonialyase ( PAL) and peroxidase ( POD) under the optimal induction condition. Results showed that the fungal elicitor induced alkalinization of the medium and increased the conductivity, and significantly increased the activity of PAL and POD of birch suspension cells, which was 5. 70 and S. 74 fold as high as the control after 6 - 10 h of treatment, respectively. These results suggested that fungal elicitation induced defense reaction in birch suspension cell. General phenylpropanoid pathway and oxidative burst might involved in the triterpenoids accumulation induced by the fungal elicitor.%将促进白桦三萜积累的拟茎点霉属的内生真菌诱导子添加到白桦悬浮培养体系中,研究40,100,400pg·mL-1的真菌诱导子对生长初期、指数生长期和生长末期的悬浮细胞干质量和三萜积累的影响.结果表明:真菌诱导子的不同诱导方案均促进白桦悬浮细胞中三萜的积累,而细胞干质量积累却被抑制;其中最佳诱导条件为在指数生长期的白桦细胞中添加40 μg·mL-1的真菌诱导子诱导1天,诱导

  3. System establishment of stem sections with a bud rapid propagation in Betula 'Royal Frost' and analysis on its influences%紫叶白桦茎芽快繁体系的建立及影响因素分析

    Institute of Scientific and Technical Information of China (English)

    杨玲; 沈海龙

    2012-01-01

    In order to develop a high-frequency plant regeneration system for Betula 'Royal Frost', taking young sterile stem section with a bud in vitro from B. 'Royal Frost' as explants, bud direct multiplication and plantlet regeneration experiments were conducted. The results showed that the optimal shoots proliferation medium was WPM medium (pH=5.4) supplemented with 0.2 μmol·L-1 6-BA and 20 g·L-1 sucrose, proliferation rate reached 10.4, and the shoots grew well. Shoots growing medium was WPM medium (pH=5.8) supplemented with 20 g·L-1 sucrose, and microshoots with 1.7 cm height and 0.89 mm of base diameter were conducted after 30 days. The microshoots became complete regenerated plantlet through exvitro rooting culture. Microshoots had the highest rooting rate of 91.5%, the most root number of 5.0, and the longest root length of 6.5 cm, in the medium with composition of 50% peat moss, 20% vermiculite and 30% pearlite. The regenerated plantlets well grew in the medium.%为建立高效的紫叶白桦组培快繁体系,以紫叶白桦试管内无菌带芽茎段作为外植体,进行芽直接增生途径的植株再生研究.结果表明:WPM+0.2 μmol·L-16-BA+20 g·L-1蔗糖(pH5.4)是适合紫叶白桦芽直接增生的增殖培养基,增殖率可达10.4,丛生芽生长状态好.WPM+20 g·L-1蔗糖(pH5.8)是适合丛生芽生长和增壮的培养基,在此培养基上培养30 d时,丛生芽可分化形成高1.7 cm、基径0.89 mm的微枝.微枝经过试管外生根培养可形成完整的再生植株.在草炭土、蛭石和珍珠岩以5:2:3体积比混合的生根基质中,微枝生根率最高(可达91.5%),不定根数量最多(5.0条),平均根长最长(6.5 cm).再生植株在上述相同基质中生长状况良好.

  4. Climatic factors affecting radial growth of Betula ermanii and Betula platypylla in Kamchatka

    Czech Academy of Sciences Publication Activity Database

    Doležal, Jiří; Ishii, H.; Kyncl, Tomáš; Takahashi, K.; Vetrova, V. P.; Homma, K.; Sumida, A.; Hara, T.

    2010-01-01

    Roč. 40, č. 2 (2010), s. 273-285. ISSN 0045-5067 R&D Projects: GA ČR GA206/05/0119; GA AV ČR IAA600050802 Institutional research plan: CEZ:AV0Z60050516 Keywords : tree-ring widths * boreal forest * Central Japan Subject RIV: EF - Botanics Impact factor: 1.574, year: 2010

  5. Short-term effects of fire disturbance on greanhouse gases emission from Betula platyphylla-forested wetland in Xiaoxing' an Mountains,Northeast China%火干扰对小兴安岭白桦沼泽温室气体排放的短期影响

    Institute of Scientific and Technical Information of China (English)

    牟长城; 张博文; 韩丽冬; 于丽丽; 顾韩

    2011-01-01

    By the methods of static chamber and gas chromatography, this paper studied the effects of fire disturbance on the seasonal dynamics and source/sink functions of CH4, CO2 and N2O emissions from Betula platyphylla-forested wetland as well as their relations with environmental factors in Xiaoxing' an Mountains of China. In growth season, slight fire disturbance on the wetland induced an increase of air temperature and ground surface temperature by 1.8- 3.9 ℃ and a decrease of water table by 6.3 cm; while heavy fire disturbance led to an increase of air temperature and 0-40 cm soil temperature by 1.4-3.8 ℃ and a decrease of water table by 33.9 cm. Under slight or no fire disturbance, the CH4 was absorbed by the wetland soil in spring but emitted in summcr and autumn; under heavy fire disturbance, the CH4 was absorbed in spring and summer but emitted in autumn. The CO2 flux had a seasonal variation of summer > spring= autumn under no fire disturbance, but of summer > autumn > spring under fire disturbance; and the N2O flux varied in the order of spring > summer > autumn under no fire disturbance, but of autumn > spring > summcr under slight fire disturbance, and of summer > spring= autumn under heavy fire disturbance.At unburned site, the CO2 flux was significantly positively correlated with air temperature and ground surface temperature; at slightly burned site, the CO2 flux had significant positive correlations with air temperature, 5-10 cm soil temperature, and water table; at heavily burned sites, there was a significant positive correlation between CO2 flux and 5-40 cm soil temperature. Fire disturbance made the CH4 emission increased by 169.5% at lightly burned site or turned into weak CH4 sink at heavily burned site, and made the CO2 and N2O emissions and the global warming potential (GWP) at burned sites decreased by 21.2% -34.7% , 65.6% -95.8% , and 22.9% -36.6% respectively, compared with those at unburned site. Therefore

  6. Fluctuation of birch (Betula L. pollen seasons in Poland

    Directory of Open Access Journals (Sweden)

    Małgorzata Puc

    2015-12-01

    Full Text Available Birch pollen grains are one of the most important groups of atmospheric biological particles that induce allergic processes. The fluctuation pattern of birch pollen seasons in selected cities of Poland is presented. Measurements were performed by the volumetric method (Burkard and Lanzoni 2000 pollen samplers. The distributions of the data were not normal (Shapiro–Wilk test and statistical error risk was estimated at a significance level of α = 0.05. Pollen season was defined as the period in which 95% of the annual total catch occurred. The linear trend for the selected features of the pollen season, skewness, kurtosis and coefficient of variation (V% were also analyzed. During the 12–14 years of study, the beginnings of birch pollen seasons were observed 7–14 days earlier, the ends were noted 5–10 days earlier, and the days with maximum values occurred 7–14 days earlier compared to the long-term data. The left-skewed distribution of the pollen season starts in most sampling sites confirms the short-lasting occurrence of pollen in the air. The threat of birch pollen allergens was high during the pollen seasons. If vegetation is highly diverse, flowering and pollen release are extended in time, spread over different weeks and occur at different times of the day. Flowering time and pollen release are affected by insolation, convection currents, wind, and turbulence. Therefore, pollen seasons are characterized by great inter-annual variability.

  7. ДЕФИНИЦИЯ ДИССЕМИНАЦИИ INONOTUS OBLIQUUS (PERS.) PIL. ТИПОМ ЛЕСА BETULA-КОНСОРЦИИ, ОПРЕДЕЛЯЮЩИМ ИНТЕГРАЛЬНУЮ КОНСТЕЛЛЯЦИЮ

    OpenAIRE

    Баландайкин, М.

    2013-01-01

    Устанавливаются особенности влияния типа леса Betula pendula Roth. на степень встречаемости в сформированных насаждениях патологического агента Inonotus obliquus (Pers.) Pil.

  8. СОДЕРЖАНИЕ ХЛОРОФИЛЛА И КАРОТИНОИДОВ В ЛИСТЬЯХ ОДУВАНЧИКА ЛЕКАРСТВЕННОГО (TARAXACUM OFFICINALE) И БЕРЕЗЫ ПОВИСЛОЙ (BETULA PENDULA ROTH), РАСТУЩИХ В Г. ТАМБОВЕ

    OpenAIRE

    Шубина, Анна

    2011-01-01

    Для оценки состояния окружающей среды в ряде районов города Тамбова изучено содержание фотосинтетических пигментов (хлорофилла а и b, каротиноидов) в листьях одуванчика лекарственного (Taraxacum officinale) и березы повислой (Betula pendula Roth).

  9. КОРРЕЛИРОВАНИЕ СОДЕРЖАНИЯ АСКОРБИНОВОЙ КИСЛОТЫ В АССИМИЛЯЦИОННОМ АППАРАТЕ BETULA PENDULA ROTH. С ДЕЙСТВИЕМ ПАТОЛОГИЧЕСКОГО АГЕНТА

    OpenAIRE

    Баландайкин, М.

    2014-01-01

    Рассматриваются особенности влияния совокупности антропогенных факторов и фитопатологического состояния дерева Betula pendula на концентрацию аскорбиновой кислоты в ассимиляционном аппарате. По критерию воздействия Inonotus obliquus (Pers.: Fr.) Pilat и присутствию поллютантов оценивалась адаптационная способность растения к действию стрессоров, а также возможность выработки механизмов, отвечающих за ингибирование биосинтеза аскорбиновой кислоты. Показано, что из всех проанализированных в дан...

  10. Determining the age of young silver birch (Betula pendula Roth) trees growing on former agricultural

    OpenAIRE

    Tkaczyk, Miłosz; Tomusiak, Robert

    2013-01-01

    In Poland, according to the law (amendment of the act of 21st May 2010) – on the provision of information on the environment and its protection, public participation in environmental protection and environmental impact assessments etc. (Official Law Journal article 08.199.1227, as amended) – the owner can cut down trees without permission, if they do not exceed the age of 10 years old. However, if an owner happens to cuts down a tree on his property without knowing the age of the ...

  11. Selective Solvents for Extraction of Triterpenes from Betula Pendula Outer Bark

    OpenAIRE

    Pāže, A; Zandersons, J; Rižikovs, J; Dobele, G.; Jurkjāne, V; Spince, B

    2013-01-01

    The volume of birch plywood production in Latvia is illustrated by the 208 000 m3 of plywood sold in 2011 and about 562 000 m3 of processed birch veneer blocks. Wood residues such as bark, veneer shorts, cut off ends and others are used as a fuel. It would be more expedient to increase the birch wood utilisation degree by involving also birch outer bark in the processing cycle. It makes up 2% of the veneer blocks’ mass. At the J.S.C. “Latvijas Finieris”, about 6000 t per year of graded and mi...

  12. Methane and nitrous oxide emissions from stems of Betula Pendula pinus sylvestris and Picea Abies

    Czech Academy of Sciences Publication Activity Database

    Macháčová, Kateřina; Halmeenmäki, E.; Pavelka, Marian; Dušek, Jiří; Bäck, J.; Urban, Otmar; Pihlatie, M.

    Helsinky: Finnish association for aerosol resarch FAAR, 2014, s. 408-412. ISBN 978-952-7091-01-2. ISSN 0784-3496. [International Aerosol Conference 2014. Busan (KR), 28.08.2014-02.09.2014] R&D Projects: GA MŠk EE2.3.20.0246 Institutional support: RVO:67179843 Keywords : methane and nitrous oxide flux * boreal forest trees Subject RIV: EH - Ecology, Behaviour

  13. Morphology of Betula pendula var. carelica bark at the pre-reproductive stage

    Directory of Open Access Journals (Sweden)

    Nadezhda N. Nikolaeva

    2014-04-01

    Full Text Available Changes in bark morphology at the pre-reproductive stage of Karelian birch are for the first time considered in connection with the type of trunk surface. The bark surface in Karelian birch changes with age from smooth to fissured. At the pre-reproductive stage Karelian birch has smooth bark with different types of exfoliation of the phellem surface layers, and tubercular specimens feature locally fissured bark on muffs at the very onset of their formation, as well as early rhytidome formation. Morphology of the bark tissues complex is a reflection of direction and intensity of the internal processes of the plant.

  14. Allometries for Widely Spaced Populus ssp. and Betula ssp. in Nurse Crop Systems

    Directory of Open Access Journals (Sweden)

    Hendrik Stark

    2013-11-01

    Full Text Available Nurse crops of widely spaced pioneer trees are a silvicultural approach to protect the regeneration of frost sensitive target tree species. If overstorey nurse crops are harvested, they can provide additional short-term benefits through increased biomass production, e.g., for bioenergy. However, the intensification of biomass exports from forests might impact negatively on ecosystem nutrient pools. Thus, precise allometric biomass equations are required to quantify biomass and nutrient removals. Since an analysis of published allometric equations developed for typical, dense aspen or birch forests showed that the tree height-to-diameter ratio correlated positively and the proportion of branch biomass negatively with stand density, we developed new allometric biomass equations for widely spaced aspen and birch growing at 4 x 4 m spacing. These equations yielded a root mean squared error of 13% when predicting total aboveground woody biomass for our sample trees. In contrast, the corresponding root mean squared error produced by allometric biomass equations from the literature ranged between 17% to 106% of actual dry biomass. Our results show that specific allometric biomass equations are needed for widely spaced pioneer trees both for accurate estimates of biomass and the nutrients contained within.

  15. Fruit wall anatomical structure of the genus Betula section Lenta (Betulaceae)

    OpenAIRE

    Olga V. Yatsenko; Igor O. Yatsenko

    2014-01-01

    The fruits of the Lentae are referred to lower syncarpous nuts. Unlike most birches, the three-lobed scales in section Lentae stay attached to the axis for a long time. The fruit wall is differentiated into epicarp (derivative of outer tissues of inferior ovary, the tissues of receptacular origin) and the pericarp itself (mesocarp and the endocarp derivating from the ovary wall). The epicarp consists of two zones: epidermis and subepidermal zone. Two-four layers of larger sclerenchymatous cel...

  16. Analysis of three types of triterpenoids in tetraploid white birches (Betula platyphylla Suk.) and selection of plus trees

    Institute of Scientific and Technical Information of China (English)

    Sui Wang; Hui Zhao; Jing Jiang; Guifeng Liu; Chuanping Yang

    2015-01-01

    Betulin, oleanolic acid, and betulinic acid are naturally occurring pentacyclic triterpenoids that have significant medicinal value. Considerable amounts of these triterpenoids are available in the outer bark of white birch. In this study, we used ultrasound-assisted extraction (UAE) to extract triterpenoids from birch bark rapidly and with high efficiency. Using high performance liquid chro-matography (HPLC), three types of triterpenoids were separated and detected. We examined the differences among triterpenoids extracted from diploid versus tetra-ploid white birch. Then, we used factor analysis to screen out tetraploid white birches with comprehensively excel-lent performance. The results indicate that the optimum conditions for extraction include the use of ethanol as an extraction solvent, a solid-to-liquid ratio of 0.1 g/10 ml, ultrasonic power set at 100 W, a temperature of 60 ?C and an extraction time of 15 min. A reversed-phase C18 col-umn (4.6 mm 9 250 mm 9 5 lm) with a column tem-perature of 30 ?C and the mobile phase composed of A (acetonitrile) and B (0.1% aqueous phosphoric acid, v/v) at a flow rate of 0.5 ml/min were used, and the detection wavelength was 195 nm. No significant difference was observed between diploid and tetraploid white birch in terms of the content of three types of triterpenoids (at a confidence level of 0.05). As triterpenoid content, height, and DBH (diameter at breast height) are strongly interre-lated, we used factor analysis to evaluate all individuals, and we screened out six plus trees with excellent com-prehensive characters.

  17. Winter warming as an important co-driver for Betula nana growth in western Greenland during the past century

    DEFF Research Database (Denmark)

    Hollesen, Jorgen; Buchwal, Agata; Rachlewicz, Grzegorz; Hansen, Birger U.; Hansen, Marc O.; Stecher, Ole; Elberling, Bo

    2015-01-01

    . To explain the strong winter importance on growth, we assessed the importance of different environmental factors using site-specific measurements from 1991 to 2011 of soil temperatures, sea ice coverage, precipitation and snow depths. The results show a strong positive growth response to the amount......Growing season conditions are widely recognized as the main driver for tundra shrub radial growth, but the effects of winter warming and snow remain an open question. Here, we present a more than 100years long Betulanana ring-width chronology from Disko Island in western Greenland that demonstrates...... a highly significant and positive growth response to both summer and winter air temperatures during the past century. The importance of winter temperatures for Betulanana growth is especially pronounced during the periods from 1910-1930 to 1990-2011 that were dominated by significant winter warming...

  18. A Preliminary Pharmacokinetic Study of Betulin, the Main Pentacyclic Triterpene from Extract of Outer Bark of Birch (Betulae alba cortex

    Directory of Open Access Journals (Sweden)

    Melanie N. Laszczyk

    2008-12-01

    Full Text Available During the last two decades triterpenes have attracted attention because of their pharmacological potential. Triterpene extract (TE from outer bark of birch consisting mainly of betulin is able to form an oleogel which was successfully tested in the treatment of actinic keratosis. Some aspects of TE in vitro pharmacology are already known. Now we show preliminary pharmacokinetics of betulin and results of a subchronic toxicity study of TE in rats and dogs. Because of poor aqueous solubility of the TE-triterpenes (< 0.1 μg/mL respectively, for pharmacokinetic studies it was suspended in sesame oil (rats, i.p. and PEG 400 / 0.9 % NaCl (dogs, s.c.. I.p. administered, betulin, the main component of TE, shows time dependency over a period of 4 h and reaches a dose-independent serum level of 0.13 μg/mL. Dose dependency was observed with s.c. administration. At 300 mg/kg a maximum plasma concentration of 0.33 μg/mL betulin was detected after 28 daily applications. The subchronic toxicity study showed no toxicity of TE in rats (i.p. and dogs (s.c.. In conclusion, triterpene extract from birch bark is safe, its betulin is bioavailable and in addition to published triterpene biological activities TE provides high potential for further pharmaceutical and pharmacological research.

  19. Cultivable actinomycetes from rhizosphere of birch (Betula pendula) growing on a coal mine dump in Silets, Ukraine.

    Science.gov (United States)

    Ostash, Bohdan; Gren, Tetiana; Hrubskyy, Yaroslav; Tistechok, Stepan; Beshley, Stepan; Baranov, Volodymyr; Fedorenko, Victor

    2014-08-01

    Five actinomycete strains were isolated from the rhizosphere of birch, one of a few native tree forms capable of thriving on the upper level of a coal mine dump near the village of Silets (Lvivska region, Ukraine). No such strains were isolated from surrounding gangue, or from nearby grass Calamagrostis epigeios. Using 16S rDNA sequencing and analysis of cell wall aminoacids, four of these strains were shown to belong to genus Streptomyces and one to be Amycolatopsis. The isolates were able to produce siderophores and antibacterial compounds. In comparison to the reference strain Streptomyces coelicolor M145, certain rhizospheric isolates displayed somewhat increased survival in the presence of copper, iron(III), or chromium(VI) salts. The Amycolatopsis isolate was also shown to accumulate significant quantities of heavy metals from waste extracts. Possible roles of the described strains in coal mine dump ecology are discussed. PMID:23686352

  20. The long range transport of birch (Betula) pollen from Poland and Germany causes significant pre-season concentrations in Denmark

    Science.gov (United States)

    Ambelas Skjoth, C.; Sommer, J.; Stach, A.; Smith, M.; Brandt, J.; Christensen, J. H.; Frohn, L. M.; Geels, C.; Hansen, K. M.; Hedegaard, G. B.

    2009-04-01

    In Denmark, where birch pollen is considered to be among the most important allergenic pollen, about one million people suffer from seasonal allergic rhinitis. In Denmark, the official reported pollen forecast is based on the daily weather forecast, the pollen calendar and local 24-h measurements. Birch pollen has the potential for long-range transport but the present Danish pollen forecast does not account for birch pollen being transported into the country from distant sources.. Long-range transport episodes are intermittent and often out of the main pollen season, where individuals in general will be medically unprotected. Here we use an integrated approach to investigate whether or not Denmark receives significant quantities of birch pollen from Poland and Germany before local trees start to flower. In 2006 we used a combination of phenological observations and pollen measurements in Poland (Poznań) and Denmark (Copenhagen). Seasonal and diurnal variations in birch pollen measurement from Copenhagen (2000-2006) were examined with the aim of identifying pre-seasonal episodes originating from long-range transport. The 2.5% accumulation method was used for identifying start of season. If daily pollen counts exceeded 30 grains/m3 either before the local flowering season began or on the actual start day, the episode was chosen for investigation with back trajectory analysis. A birch forest inventory for Northern Europe was produced and implemented in DEHM-Pollen along with a simple unified pollen release model SUPREME to investigate the 2006 campaign in detail. In 2006, full flowering took place in Poznan between 20th and 28th of April and daily concentrations varied between 739 and 2169 grains/m3. In Copenhagen phenological observations showed that local flowering was initiated the 2nd of May. In Copenhagen several episodes with pollen concentrations at 108, 244 and 41 grains/m3 were recorded the 23rd, 26th and 27th of April, respectively. Back-trajectory analysis showed that for those tree dates the origin of the air masses was Poland including the Poznan region. 11 possible pre-seasonal long-range transport episodes in 2000-2006 were identified during analyses of the measured pollen data. All possible long-range transport episodes were investigated with back trajectories. In all investigated episodes, the air masses Copenhagen originated directly from either Germany or Poland. The model results from DEHM pollen for 2006 show several episodes in Copenhagen with high pollen concentration for the 23rd - 24th and 26th - 27th of April, respectively. These pre-seasonal peaks in 2006 were modelled well with respect to timing and magnitude. During this period the SUPREME model only predicts birch pollen emission south of Denmark. Long-range transport episodes of birch pollen from Poland and Germany has happened almost every year since 2000 and it is therefore likely that this is a general pattern. It is shown that DEHM-Pollen for the year 2006 is able to simulate pre-seasonal pollen concentrations in Denmark, where key components include a well calibrated emission model and emission inventory. Furthermore, all model components are prepared for full implementation in the THOR air pollution and forecasting system. During pre-seasonal, pollen allergy patients are in general medically unprotected. Such episodes will therefore have a full impact with respect to allergic reactions among the allergy patients. The use of the integrated approach improves knowledge of such episodes. Furthermore, an implementation of DEHM-Pollen in the THOR system has the potential to provide early warnings of severe pre-seasonal pollen episodes to the entire Danish population, by forecasting how far and how severe a possible pre-seasonal birch pollen cloud will progress into Denmark.

  1. The pattern of intrapopulational and interpopulational changes of Betula pendula in Iran, based on leaf morphological traits

    OpenAIRE

    Mohammad Esmaeilpour Poodeh; Kambiz Taheri Abkenar; Ali Aalami; Amireslam Bonyad

    2014-01-01

    Despite superior medicinal properties of Birch, there aren’t any studies reported on its morphological diversity. For the first time, leaf samples were collected from four different sites, each site 10 trees and each tree 30 fertile and sterile shoots and leaves (totally 2400). In analyzing the mean values, the Siahmarz kuh showd the maximum and the Marmishoo minimum size mean. Angle of leaf base and number of veins had minimum and fluctuating asymmetry and distance border had a maximum coeff...

  2. The pattern of intrapopulational and interpopulational changes of Betula pendula in Iran, based on leaf morphological traits

    Directory of Open Access Journals (Sweden)

    Mohammad Esmaeilpour Poodeh

    2014-04-01

    Full Text Available Despite superior medicinal properties of Birch, there aren’t any studies reported on its morphological diversity. For the first time, leaf samples were collected from four different sites, each site 10 trees and each tree 30 fertile and sterile shoots and leaves (totally 2400. In analyzing the mean values, the Siahmarz kuh showd the maximum and the Marmishoo minimum size mean. Angle of leaf base and number of veins had minimum and fluctuating asymmetry and distance border had a maximum coefficient of variation, minimum and maximum morphological diversity respectively. Average size of sterile leaf traits was larger than average size of fertile leaf traits. It seemed that Siahmarz Kuh is had the most interapopulation diversity and could apply a transition source to sink. The slightest change in the veins of the population in birch was more strongly controlled by genes. Multivariate analyses of variance indicated high statistical significance of all factors: leaf type, population, type population, tree nested population and type × tree nested population. The cluster analysis identified three clusters, the first cluster contained only Marmishoo trees. Because the majority of the population, geographic distribution of genotypes was not consistent with the grouping that could be due to the influence of environmental factors on morphological traits, so it is recommended to use molecular markers. Canonical discriminant analysis showed that petiole length ratio and fluctuating asymmetry could be used in future research on morphological diversity among populations of B. pendula.

  3. The role of summer precipitation and summer temperature in establishment and growth of dwarf shrub Betula nana in northeast Siberian tundra

    DEFF Research Database (Denmark)

    Li, Bingxi; Heijmans, Monique M P D; Berendse, Frank;

    2016-01-01

    variables and local shrub dominance. We found that establishment of shrub ramets was positively related to summer precipitation, which implies that the current high dominance of B. nana at our study site could be related to high summer precipitation in the period from 1960 to 1990. The results confirmed...... that early summer temperature is most influential to annual growth rates of B. nana. In addition, summer precipitation stimulated shrub growth in years with warm summers, suggesting that B. nana growth may be co-limited by summer moisture supply. The dual controlling role of temperature and summer...

  4. Constitutive Model of Single Root System’s Resistance to Tensile Stress - Taking Pinus tabulaeformis, Betula platyphylla, Quercus mongolica and Larix gmelinii as Experimental Objects

    OpenAIRE

    Lihua Chen; Pinghua Wang; Yuanjun Yang; Jia He

    2014-01-01

    A constitutive model for the stress-strain relationship of single forest root system was developed in order to provide theoretical foundations for the mechanisms of soil-reinforcement by root system and offer a reliable basis for the analysis of root tensile strength character. This study started a general form of linear and non-linear stress-strain relation that was mathematically defined by four boundary conditions observed in typical tensile tests of single roots. The parameters of the mod...

  5. Characteristics of soil respiration temperature sensitivity in a Pinus/Betula mixed forest during periods of rising and falling temperatures under the Japanese monsoon climate

    Directory of Open Access Journals (Sweden)

    Yusuke Oe

    2011-06-01

    Full Text Available We studied temperature sensitivity characteristics of soil respiration during periods of rising and falling temperatureswithin a common temperature range. We measured soil respiration continuously through two periods (a period of fallingtemperature, from August 7, 2003 to October 13, 2003; and a period of rising temperature from May 2, 2004 to July 2,2004 using an open-top chamber technique. A clear exponential relationship was observed between soil temperatureand soil respiration rate during both periods. However, the effects of soil water content were not significant, becausethe humid monsoon climate prevented soil drought, which would otherwise have limited soil respiration. We analyzedtemperature sensitivity using the Q10 value and Rref (reference respiration at the average temperature for the observationperiod and found that these values tended to be higher during the period of rising temperature than during theperiod of falling temperature. In the absence of an effect on soil water content, several other factors could explain thisphenomenon. Here, we discuss the factors that control temperature sensitivity of soil respiration during periods of risingand falling temperature, such as root respiration, root growth, root exudates, and litter supply. We also discuss how thecontribution of these factors may vary due to different growth states or due to the effects of the previous season, despitea similar temperature range.

  6. Effects of solar UV-A and UV-B radiation on gene expression and phenolic accumulation in Betula pendula leaves

    Energy Technology Data Exchange (ETDEWEB)

    Morales, L.O.; Tegelberg, R.; Brosche, M.; Aphalo, P.J. [Helsinki Univ., Helsinki (Finland). Dept. of Biosciences, Div. of Plant Biology; Keinanen, M. [Eastern Finland Univ., Joensuu (Finland). Faculty of Biosciences; Lindfors, A. [Edinburgh Univ., Edinburgh (United Kingdom). School of Geosciences, Grant Inst.

    2010-07-15

    Several physiological and ecological processes in plant ecosystems are regulated by solar ultraviolet (UV) radiation. Although UV radiation is an important environmental factor for plant communities, plant responses to solar UV are not fully understood. Therefore, this study examined the effects of different doses of solar UV-A and UV-B radiation on the expression of genes involved in flavonoid biosynthesis and on the accumulation of phenolic compounds in birch leaves after 30 days of exposure outdoors. Plants were exposed to 6 UV treatments using 3 types of plastic film. Epidermal flavonoids measured in vivo decreased when UV-B was excluded. Liquid chromatography-mass spectrometry revealed that the concentrations of 6 flavenoids declined linearly with UV-B exclusion, and transcripts of PAL and HYH measured by quantitative real-time polymerase chain reaction were expressed at lower levels. The results provide a better understanding of plant responses to solar UV radiation at both molecular and metabolite levels. It was concluded that different doses of solar UV-A and UV-B radiation differentially regulate gene expression and the accumulation of flavonoids in birch leaves. 63 refs., 3 tabs., 3 figs.

  7. 以光合效率度量天然白桦种群生态位初探%Primary Probing into Niche of Natural Betula platyphylla Population by Means of Photosynthetic Efficiency

    Institute of Scientific and Technical Information of China (English)

    王爱民; 祖元刚

    2002-01-01

    In terms of photosynthetic efficiency,which demonstrates the space-time function of plant,niche width of B. Platyphylla population was described.First,on the basis of net photosynthetic amount in certain time,the niche width of a birch was calculated.Then,the realized niche and rudimental niche of B. Platyphylla seedlings,young trees and adult trees were discussed.Finally, the dynamic of niche under special conditions was studied.

  8. Estrés oxidativo y respuestas fisiológicas a la acumulación de metales pesados en Betula celtiberica micorrizada y no micorrizada cultivada en un suelo contaminado

    OpenAIRE

    Murube Torcida, Ester Maria

    2014-01-01

    Los metales pesados no son biodegradables lo que hace que sean contaminantes muy persistentes en el medio ambiente, lo que supone un grave riesgo no sólo para la salud medioambiental sino también para la salud humana. La fitorremediación se presenta como una alternativa biológica sencilla y viable en la descontaminación de suelos; sin embargo, está influenciada por la biodisponibilidad de los metales pesados en el suelo así como por su toxicidad y por las actividades microbianas de la rizosfe...

  9. Is it appropriate protective figure "Plant Micro-Reserves" to protect tree species? The example of Betula pendula subsp. fontqueri in "La Garganta de los Caballeros" (Ávila)

    OpenAIRE

    Martinez Fernandez, Vanesa; Martinez Garcia, Felipe; Sardinero Roscales, Santiago

    2011-01-01

    The figure of protection "micro-reserves" was created in the Region of Valencia (ANONYMOUS, 1994) with the aim of protecting endangered plant species. This is one of the areas of greatest floristic richness and uniqueness of the western Mediterranean. In this area rare, endemic or threatened vascular flora has a peculiar distribution: they appear to form small fragments spread over the entire region (LAGUNA, 1994; LAGUNA, 2001) The protection of every these small populations of great scientif...

  10. Introduction to Distribution and Ecology of Sterile Conks of Inonotus obliquus

    OpenAIRE

    Lee, Min-Woong; Hur, Hyeon; Chang, Kwang-Choon; Lee, Tae-Soo; Ka, Kang-Hyeon; Jankovsky, L.

    2008-01-01

    Inonotus obliquus is a fungus that causes white heart rot on several broad-leaved species. This fungus forms typical charcoal-black, sterile conks (chaga) or cinder conks on infected stems of the birche (Betula spp). The dark brown pulp of the sterile conk is formed by a pure mycelial mass of fungus. Chaga are a folk remedy in Russia, reflecting the circumboreal distribution of I. obliquus in boreal forest ecosystems on Betula spp. and in meridional mountain forests on beech (Fagus spp.) in R...

  11. Plant pollen content in the air of Lublin (central-eastern Poland) and risk of pollen allergy

    OpenAIRE

    Krystyna Piotrowska-Weryszko; Elżbieta Weryszko-Chmielewska

    2014-01-01

    Pollen monitoring was carried out in Lublin in 2001–2012 by the volumetric method using a Hirst-type spore trap (Lanzoni VPPS 2000). Daily pollen concentrations considerably differed in the particular years. The pollen counts with the biggest variability were observed in the first half of a year when woody plants flowering. The highest annual pollen index were noted for the following taxa: [i]Betula, Urtica,[/i] Pinaceae, Poaceae and [i]Alnus[/i]. [i]Betula[/i] annual total showed the greates...

  12. КАТАЛИТИЧЕСКОЕ ОКИСЛЕНИЕ БЕРЕЗОВОЙ ДРЕВЕСИНЫ (BETULA PENDULA ROTH.) КИСЛОРОДОМ В СИРЕНЕВЫЙ АЛЬДЕГИД И ВАНИЛИН

    OpenAIRE

    Коропачинская, Н.; Тарабанько, В.; Черняк, М.

    2003-01-01

    Исследован процесс окисления березовой древесины молекулярным кислородом в статическом качающемся реакторе. Изучено влияние катализатора, температуры и количества загруженного субстрата на выход сиреневого альдегида и ванилина. Добавки гидроксида меди в качестве катализатора вдвое увеличивают выход альдегидов по сравнению с некаталитическим процессом. Увеличение содержания древесины в реакционной массе снижает выходы альдегидов при окислении. Достигнуты выходы ароматических альдегидов до 42 в...

  13. Expansion of invasive species on ombrotrophic bogs: desiccation or high N deposition?

    NARCIS (Netherlands)

    Tomassen, H.B.M.; Smolders, A.J.P.; Limpens, J.; Lamers, L.P.M.; Roelofs, J.G.M.

    2004-01-01

    1. In many ombrotrophic bog areas the invasion of grass (e.g. Molinia caerulea) and tree (e.g. Betula pubescens) species has become a major problem. We investigated whether the invasion of such species is due to high atmospheric nitrogen (N) deposition by conducting a fertilization experiment. 2. Th

  14. Effective height development of four co-occurring species in the gap-phase regeneration of Douglas fir monocultures under nature-oriented conversion. Forest Ecology and Management, Pages 189-198

    NARCIS (Netherlands)

    Dekker, M.; Breugel, van M.; Sterck, F.J.

    2007-01-01

    Natural regeneration in gaps in Douglas fir forest stands in the Netherlands mainly consists of Betula pendula (Roth.), Pinus sylvestris (L.), Larix kaempferi (Carr.), and Pseudotsuga menziesii (Mirb. Franco). Even though these species are well known, the autogenic development of these species in an

  15. COMPREHENSIVE CHARACTERISTIC OF PINE AND BIRCH SPECIES WITH DIFFERENT SCHEME OF COMBINATION Сравнительная характеристика сосново-березовых культур с различной схемой смешения

    Directory of Open Access Journals (Sweden)

    Shamiryan K. G.

    2012-09-01

    Full Text Available The article presents the characteristics of condition and growth of Pinus sylvestris and Betula Pendula in their cohabitation in poor sand soils (A2 in the condition of some forest enterprises of Voronezh region; the most effective way of combination of this species is revealed

  16. Environ: E00796 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00796 Birch Medicinal herb Quercetin [CPD:C00389], Kaempferol [CPD:C05903], Salicy...late, Tannin, Ascorbate [CPD:C00072] Betula pendula [TAX:3505] Betulaceae Birch leaves Medicinal herbs [BR:br08322] Dicot plants: rosids Betulaceae (birch famly) E00796 Birch ...

  17. Flynn Effects on Sub-Factors of Episodic and Semantic Memory: Parallel Gains over Time and the Same Set of Determining Factors

    Science.gov (United States)

    Ronnlund, Michael; Nilsson, Lars-Goran.

    2009-01-01

    The study examined the extent to which time-related gains in cognitive performance, so-called Flynn effects, generalize across sub-factors of episodic memory (recall and recognition) and semantic memory (knowledge and fluency). We conducted time-sequential analyses of data drawn from the Betula prospective cohort study, involving four age-matched…

  18. Birch pollen allergy: molecular characterization and hypoallergenic products

    NARCIS (Netherlands)

    Schenk, M.F.

    2008-01-01

    Allergic diseases, such as hay fever and food allergy, affect a substantial part of the population in westernized countries. Pollen of the European white birch (Betula pendula) is a considerable cause of hay fever (seasonal allergic rhinitis) in northern and central Europe. The major birch pollen al

  19. Records of mining Lepidoptera in Belgium with nine species new to the country (Nepticulidae, Opostegidae, Tischeriidae, Lyonetiidae)

    OpenAIRE

    Nieukerken, van, A.

    2006-01-01

    Records of 56 species of mining Lepidoptera are given, mostly for Wallonia. Stigmella thuringiaca (Namur: Nismes, on Potentilla tabernaemontani), Ectoedemia arcuatella (Luxembourg, Namur, on Fragaria vesca) and Leucoptera lustratella (Luxembourg, Namur, on Hypericum perforatum) are reported new for Belgium on the basis of reared adults, Stigmella crataegella (Luxembourg: Belvaux, Crataegus monogyna), S. confusella (West Vlaanderen, Betula pubescens), Trifurcula subnitidella (Namur: Nismes, Lo...

  20. Beiträge zur Fortschreibung der Florenliste Deutschlands (Pteridophyta, Spermatophyta)

    OpenAIRE

    Buttler, Karl Peter; Hand, Ralf

    2007-01-01

    Im Rahmen der Vorarbeiten für eine neue Florenliste Deutschlands werden Nomenklaturaspekte bei Achillea collina, Anthriscus, Betula pubescens subsp. carpatica, Camelina microcarpa, Hordelymus, Populus nigra subsp. betulifolia, Silene baccifera sowie bei einigen von Cesati publizierten Unterart- Kombinationen diskutiert. Bei Urtica wird ein alternatives taxonomisches Konzept vorgeschlagen. Die beiden folgenden bisher nicht verfügbaren Kombinationen wurden notwendig: Populus nigra subsp. betuli...

  1. A Greener Arctic: Vascular Plant Litter Input in Subarctic Peat Bogs Changes Soil Invertebrate Diets and Decomposition Patterns

    Science.gov (United States)

    Krab, E. J.; Berg, M. P.; Aerts, R.; van Logtestijn, R. S. P.; Cornelissen, H. H. C.

    2014-12-01

    Climate-change-induced trends towards shrub dominance in subarctic, moss-dominated peatlands will most likely have large effects on soil carbon (C) dynamics through an input of more easily decomposable litter. The mechanisms by which this increase in vascular litter input interacts with the abundance and diet-choice of the decomposer community to alter C-processing have, however, not yet been unraveled. We used a novel 13C tracer approach to link invertebrate species composition (Collembola), abundance and species-specific feeding behavior to C-processing of vascular and peat moss litters. We incubated different litter mixtures, 100% Sphagnum moss litter, 100% Betula leaf litter, and a 50/50 mixture of both, in mesocosms for 406 days. We revealed the transfer of C from the litters to the soil invertebrate species by 13C labeling of each of the litter types and assessed 13C signatures of the invertebrates Collembola species composition differed significantly between Sphagnum and Betula litter. Within the 'single type litter' mesocosms, Collembola species showed different 13C signatures, implying species-specific differences in diet choice. Surprisingly, the species composition and Collembola abundance changed relatively little as a consequence of Betula input to a Sphagnum based system. Their diet choice, however, changed drastically; species-specific differences in diet choice disappeared and approximately 67% of the food ingested by all Collembola originated from Betula litter. Furthermore, litter decomposition patterns corresponded to these findings; mass loss of Betula increased from 16.1% to 26.2% when decomposing in combination with Sphagnum, while Sphagnum decomposed even slower in combination with Betula litter (1.9%) than alone (4.7%). This study is the first to empirically show that collective diet shifts of the peatland decomposer community from mosses towards vascular plant litter may drive altered decomposition patterns. In addition, we showed that

  2. Protective Activity Against Oxidative Stress of Plants Indigenous to Korea

    International Nuclear Information System (INIS)

    We have screened the cytoprotective effect against Ha, Oa, and γ-ray radiation induced oxidative stress from 32 Korean plants. Betula ermani var, saitoana (caulis, leaves), Rosa wichuraiana (caulis), Sorbus commixta (caulis), Weigela florida (leaves), Cirsium rhinoceros (whole plant), and Viburnum erosum (caulis) were found to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and intracellular reactive oxygen species (ROS). As a result, extracts of six plants reduced cell death of Chinese hamster lung fibroblast (V79-4) cells induced by Ha,Oa, treatment. In addition, these extracts protected cell death of V79-4 cells damaged by γ-ray radiation. In addition, these extracts scavenged ROS generated by radiation. Taken together, the results suggest that Betula ermani var. saitoana, Rosa wichuraiana, Sorbus commixta, Weigela florida, Cirsium rhinoceros, and Viburnum erosum protect V79-4 cells against oxidative damage by radiation through scavenging ROS

  3. Spruce forests (Ass. Sphango girgensohnii - Piceetum (Br.-Bl. 39 Polak. 62 on excessively moistened peatlands in Latvia

    Directory of Open Access Journals (Sweden)

    Normunds Priedits

    2014-02-01

    Full Text Available The research carried out on swamp spruce forests on peatland in Latvia gives a detailed notion of the phytosociological structure of Ass. Sphagno girgensohnii - Piceetum (Br. - BI. 39 Polak. 62 in the western part of the East-European Plain at the Baltic Sea. The paper reflects one of the aspects of swamp forest investigation results in Latvia on forest communities, its biodiversity and presevation. Ninety-one sample plots with Picea abies as the dominant in the tree layer or co-dominant with Betula pendula, Betula pubescens or Pinus sylvestris are described according to phytosociological Braun-Blanquet methodology. Floristic features of spruce communities belonging to Caricoso-phragmitosa and Dryopterioso-cnricosa forest site types are analysed. The results are compared with similar investigations carried out in the Baltic Sea region states and neighbouring countries.

  4. Microclimate and Modeled Fire Behavior Differ Between Adjacent Forest Types in Northern Portugal

    OpenAIRE

    2014-01-01

    Fire severity varies with forest composition and structure, reflecting micrometeorology and the fuel complex, but their respective influences are difficult to untangle from observation alone. We quantify the differences in fire weather between different forest types and the resulting differences in modeled fire behavior. Collection of in-stand weather data proceeded during two summer periods in three adjacent stands in northern Portugal, respectively Pinus pinaster (PP), Betula alba (BA), and...

  5. Pestalotioid fungi from Restionaceae in the Cape Floral Kingdom.

    OpenAIRE

    2006-01-01

    Eight pestalotioid fungi were isolated from the Restionaceae growing in the Cape Floral Kingdom of South Africa. Sarcostroma restionis, Truncatella megaspora, T. restionacearum and T. spadicea are newly described. New records include Pestalotiopsis matildae, Sarcostroma lomatiae, Truncatella betulae and T. hartigii. To resolve generic affiliations, phylogenetic analyses were performed on ITS (ITS1, 5.8S, ITS2) and part of 28S rDNA. DNA data support the original generic concept of Truncatella,...

  6. Shear Force Capacity of Various Doweled Frame Type Furniture Joints

    OpenAIRE

    KASAL, Ali; ERDİL, Yusuf Ziya; DEMİRCİ, Selçuk; ECKELMAN, Carl A.

    2013-01-01

    Tests were carried out to determine the ultimate shear force capacity of numerous of doweled frame type furniture joints under controlled laboratory conditions. Sugar maple (Acer saccharum), soft maple (Acer negund), yellow poplar (Liriodendron tulipifera), sweetgum (Liquidambar styraciflua) and black walnut (Juglans nigra)were utilized in constructing the joint specimens, but all dowels were cut from yellow birch (Betula papyrifera) and sugar maple (Acer saccharum). Two types of specimens we...

  7. Does tree seedling growth and survival require weeding of Himalayan balsam (Impatiens glandulifera)?

    OpenAIRE

    Ammer, Christian; Schall, Peter; Wördehoff, René; Lamatsch, Klaus; Bachmann, Martin

    2011-01-01

    The effect of Himalayan balsam (Impatiens glandulifera) on survival and growth of naturally regenerated silver birch (Betula pendula) and planted Norway spruce (Picea abies) and silver fir (Abies alba) seedlings was studied in a weeding experiment over 3 years. Three different treatments were applied: control, mowing, and hand weeding by pulling out the entire plant. There were no consistent treatment effects on height and diameter of the tree seedlings. The coverage of Rubus fruticosus had a...

  8. Effect of Root Moisture Content and Diameter on Root Tensile Properties

    OpenAIRE

    Yuanjun Yang; Lihua Chen; Ning Li; Qiufen Zhang

    2016-01-01

    The stabilization of slopes by vegetation has been a topical issue for many years. Root mechanical characteristics significantly influence soil reinforcement; therefore it is necessary to research into the indicators of root tensile properties. In this study, we explored the influence of root moisture content on tensile resistance and strength with different root diameters and for different tree species. Betula platyphylla, Quercus mongolica, Pinus tabulaeformis, and Larix gmelinii, the most ...

  9. DYNAMICS AND DISTINCTIONS IN CONCENTRATION OF THE BASIC PHOTOSYNTHETIC PIGMENTS OF LEAVES OF THE BIRCH GROWING IN IMPURE CONDITIONS

    OpenAIRE

    Михаил Эдуардович Баландайкин

    2014-01-01

    The complex of features of influence of external factors on frame of the basic photosynthetic pigments of a sheet plate of a birch is discussed. Besides, specificity of influence of the infectious pathological stress-factor – xylotroph basidial macromycet (facultative saprotroph) a tinder fungus bevelled – on the content of a chlorophyll of phylum a, b, their sums, lipochromes, an interrelation of pigments in sheet plates of trees Betula pendula Roth. is shown.

  10. DYNAMICS AND DISTINCTIONS IN CONCENTRATION OF THE BASIC PHOTOSYNTHETIC PIGMENTS OF LEAVES OF THE BIRCH GROWING IN IMPURE CONDITIONS

    Directory of Open Access Journals (Sweden)

    Михаил Эдуардович Баландайкин

    2014-09-01

    Full Text Available The complex of features of influence of external factors on frame of the basic photosynthetic pigments of a sheet plate of a birch is discussed. Besides, specificity of influence of the infectious pathological stress-factor – xylotroph basidial macromycet (facultative saprotroph a tinder fungus bevelled – on the content of a chlorophyll of phylum a, b, their sums, lipochromes, an interrelation of pigments in sheet plates of trees Betula pendula Roth. is shown.

  11. White Birch Trees as Resource Species of Russia : Their Distribution, Ecophysiological Features, Multiple Utilizations

    OpenAIRE

    Zyryanova, Olga A.; TERAZAWA, Minoru; KOIKE, TAKAYOSHI; Zyryanov, Vyacheslav I.

    2010-01-01

    Four birch tree species (Betula costata, B. pendula, B. platyphylla, B. pubescens) are traditionally important resource species in Russia. In the article, we discuss their spatial and ecophysiological features, biochemical constituents of the living tissues of the birches such as the wood, outer and inner bark, twigs, leaves, buds, roots. The exudation, tapping periods and sap productivity, exudated birch sap and derived birch tar are also reviewed. We show numerous useful wooden, medicinal, ...

  12. Perceived chronic stress, health and cognition

    OpenAIRE

    Öhman, Lena

    2006-01-01

    The aim of this licentiate thesis was to examine consequences of chronic stress for stressrelated diseases and to investigate the chronic stress – cognition relationship. In the first study data covering ten years was used from the Betula Prospective Cohort Study (Nilsson et al., 1997). Based on the ratings on a stress scale, matched samples between 40 and 65 years of age were divided into a high and low stress group. The reported incidence of cardiovascular, diabetes, psychiatric, tumor, and...

  13. ACCUMULATION OF HEAVY METALS IN LEAF LITTER OF DIFFERENT TREE SPECIES IN URBAN AREAS

    OpenAIRE

    Konoshina, S.; Khilkova, N.

    2015-01-01

    Analysis of heavy metal accumulation of leaf litter of woody plants: Aesculus hippocastanum Aesculus hippocastanum, heart-shaped linden Tilia cordata, Siberian larch Larix sibirica, mountain ash Sorbus aucuparia, warty birch Betula verrucosa, growing within Orel City is given. The kinds of woody plants, which leaf litter has the largest accumulation of heavy metals are determined. The maximum total content of heavy metals in leaf litter was observed in mountain ash and birch.

  14. Selection of trees for rubbing by red and roe deer in forest plantations

    OpenAIRE

    Ramos, Jaime; Bugalho, Miguel; Cortez, José Paulo; Iason, Glenn

    2006-01-01

    Antler rubbing is a form of behaviour by which deer may damage and ultimately induce mortality of trees. Understanding factors affecting selection of trees for rubbing may contribute to mitigation of negative effects of such behaviour in plantations or woodlands. We analysed characteristics of trees rubbed by red and roe deer along transects established in plantations of Pinus pinaster (Aiton), Pseudotsuga menziesii (Mirbel) Franco, Betula alba L. and Quercus robur L. in Northeast Portugal. T...

  15. Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch

    OpenAIRE

    Chiang Vincent L; Tiimonen Heidi; Mäkelä Riina; Vuosku Jaana; Saranpää Pekka; Laakso Tapio; Edesi Jaanika; Niemi Karoliina; Sutela Suvi; Koskimäki Janne; Suorsa Marja; Julkunen-Tiitto Riitta; Häggman Hely

    2009-01-01

    Abstract Background The monolignol biosynthetic pathway interconnects with the biosynthesis of other secondary phenolic metabolites, such as cinnamic acid derivatives, flavonoids and condensed tannins. The objective of this study is to evaluate whether genetic modification of the monolignol pathway in silver birch (Betula pendula Roth.) would alter the metabolism of these phenolic compounds and how such alterations, if exist, would affect the ectomycorrhizal symbiosis. Results Silver birch li...

  16. Books received by the Rijksherbarium library

    OpenAIRE

    NN

    1992-01-01

    The fifth issue of this series comprises extended keys for the determination of 148 species of Ectomycorrhizae (Abies 1, Betula 17, Carpinus 1, Fagus 31, Larix 10, Picea 51, Pinus 33, Pseudotsuga 4, and Quercus 2). The glossary, synoptic tables, literature as well as proposals for the arrangement of the plates are updated. Volume 5 comprises 16 plates of ectomycorrhiza with photo in colour, half tone photographs showing diagnostic details, and extensive legends. This series is an excellent pi...

  17. Books received by the Rijksherbarium library

    OpenAIRE

    NN

    2001-01-01

    The eleventh issue of this series gives 26 sheets with coloured and/or black-and-white photographs of 11 unidentified and 16 identified species of Ectomycorrhizae. The morphology is extensively described. Several keys are given for the identification of ectomycorrhiza with respect to the tree genera Abies, Alnus, Betula, Carpinus, Corylus, Cyclobalanopsis, Elaeocarpus, Eucalyptus, Fagus, Larix, Nothofagus, Pasania, Picea, Pinus, Populus, Pseudotsuga, Quercus, Salix, Shorea, Tetraberlinia, and...

  18. Effects of Flavonoid-rich Plant Extracts on In vitro Ruminal Methanogenesis, Microbial Populations and Fermentation Characteristics

    OpenAIRE

    Kim, Eun T.; Guan, Le Luo; Lee, Shin J.; Sang M. Lee; Lee, Sang S.; Lee, Il D.; Lee, Su K.; Lee, Sung S.

    2015-01-01

    The objective of this study was to evaluate the in vitro effects of flavonoid-rich plant extracts (PE) on ruminal fermentation characteristics and methane emission by studying their effectiveness for methanogenesis in the rumen. A fistulated Holstein cow was used as a donor of rumen fluid. The PE (Punica granatum, Betula schmidtii, Ginkgo biloba, Camellia japonica, and Cudrania tricuspidata) known to have high concentrations of flavonoid were added to an in vitro fermentation incubated with r...

  19. Properties of Modified Phenol-Formaldehyde Adhesive for Plywood Panels Manufactured from High Moisture Content Veneer

    OpenAIRE

    Pavlo Bekhta; Galyna Ortynska; Jan Sedliacik

    2015-01-01

    This paper presents the results of laboratory investigations of bonding high moisture content (15 %) birch veneers (Betula pubescens Ehrh.) with the use of modifi ed phenol-formaldehyde (PF) resin. Wheat starch, rye flour, resorcinol and phenol-resorcinol-formaldehyde resin were chosen as modifying agents. Dynamic viscosity, hydrogen ions concentration, solid content, curing time, pot life of developed adhesive compositions and shear strength of plywood samples were evaluated. ANOVA analysis ...

  20. Root system traits of Norway spruce, Scots pine, and silver birch in mixed boreal forests: an analysis of root architecture, morphology, and anatomy

    OpenAIRE

    Kalliokoski, Tuomo

    2011-01-01

    The aim of this thesis was to unravel the functional-structural characteristics of root systems of Betula pendula Roth., Picea abies (L.) Karst., and Pinus sylvestris L. in mixed boreal forest stands differing in their developmental stage and site fertility. The root systems of these species had similar structural regularities: horizontally-oriented shallow roots defined the horizontal area of influence, and within this area, each species placed fine roots in the uppermost soil layers, w...

  1. Nuclear magnetic resonance (NMR) studies of homeopathic solutions.

    Science.gov (United States)

    Aabel, S; Fossheim, S; Rise, F

    2001-01-01

    The efficacy of homeopathy is controversial. Nuclear magnetic resonance (NMR) has been used to study homeopathic solutions, showing provocative results. We examined the reproducibility of one of the allegedly positive studies. 1H NMR spectra were recorded for Sulphur D4, diluted and succussed up to D30 (called potentization) at two different frequencies (300 and 500 MHz). The Sulphur solution had been potentiated according to homeopathic principles with deionized water and alcohol. Water proton T1 relaxation measurements were performed also at 20 MHz for the different potentiated Sulphur solutions. Furthermore, the homeopathic remedy Betula alba 30c (birch pollen extract) and appropriate control solution (deionized water, unsuccussed solutions and placebo globules) were measured analogously, both with frequencies giving spectra and T1 relaxometry. The Sulphur remedies showed identical one dimensional proton spectra (1H NMR) at 300 and 500 MHz, regardless of dilution/succussion stage, from D4 to D30. Furthermore, Betula 30c as a potentiated solution and its controls (ethanol dilutions and Betula diluted but not succussed) showed identical spectra. Nor were there any statistically significant differences in longitudinal (T1) relaxation times between deionized water and Sulphur D10 to D30 preparations. The shorter T1 of the Sulphur D4 preparation could be ascribed to the higher microviscosity within the sample matrix caused by the high concentration of dissolved material. Also, the T1 values of the Betula alba 30c preparation (in globular form) and control placebo globules were identical. In conclusion, published results from NMR research on homeopathy indicating differences between homeopathic solutions and control samples could not be reproduced. PMID:11212083

  2. Spatial distribution of forests and woodlands in Iceland in accordance with the CORINE land cover classification

    OpenAIRE

    Björn Traustason 1971; Arnór Snorrason 1960

    2014-01-01

    This paper presents a united geographical database for all known forest and woodland areas in Iceland, both natural and planted. This first edition of the database follows forest and woodland classifications used in the European CORINE land cover program. According to the database, the total area of forests and woodlands in Iceland was estimated as being 156,800 ha, divided into natural downy birch (Betula pubescens) woodland (115,400 ha) and forest plantations (41,400 ha). The natural birch ...

  3. Vegetation and environmental responses to climate forcing during the Last Glacial Maximum and deglaciation in the East Carpathians: attenuated response to maximum cooling and increased biomass burning

    Science.gov (United States)

    Magyari, E. K.; Veres, D.; Wennrich, V.; Wagner, B.; Braun, M.; Jakab, G.; Karátson, D.; Pál, Z.; Ferenczy, Gy; St-Onge, G.; Rethemeyer, J.; Francois, J.-P.; von Reumont, F.; Schäbitz, F.

    2014-12-01

    The Carpathian Mountains were one of the main mountain reserves of the boreal and cool temperate flora during the Last Glacial Maximum (LGM) in East-Central Europe. Previous studies demonstrated Lateglacial vegetation dynamics in this area; however, our knowledge on the LGM vegetation composition is very limited due to the scarcity of suitable sedimentary archives. Here we present a new record of vegetation, fire and lacustrine sedimentation from the youngest volcanic crater of the Carpathians (Lake St Anne, Lacul Sfânta Ana, Szent-Anna-tó) to examine environmental change in this region during the LGM and the subsequent deglaciation. Our record indicates the persistence of boreal forest steppe vegetation (with Pinus, Betula, Salix, Populus and Picea) in the foreland and low mountain zone of the East Carpathians and Juniperus shrubland at higher elevation. We demonstrate attenuated response of the regional vegetation to maximum global cooling. Between ˜22,870 and 19,150 cal yr BP we find increased regional biomass burning that is antagonistic with the global trend. Increased regional fire activity suggests extreme continentality likely with relatively warm and dry summers. We also demonstrate xerophytic steppe expansion directly after the LGM, from ˜19,150 cal yr BP, and regional increase in boreal woodland cover with Pinus and Betula from 16,300 cal yr BP. Plant macrofossils indicate local (950 m a.s.l.) establishment of Betula nana and Betula pubescens at 15,150 cal yr BP, Pinus sylvestris at 14,700 cal yr BP and Larix decidua at 12,870 cal yr BP. Pollen data furthermore support population genetic inferences regarding the regional presence of some temperate deciduous trees during the LGM (Fagus sylvatica, Corylus avellana, Fraxinus excelsior). Our sedimentological data also demonstrate intensified aeolian dust accumulation between 26,000 and 20,000 cal yr BP.

  4. The effects of physical activity on the association between self-reported stress and episodic memory performance

    OpenAIRE

    Rajamäki, Suvi

    2010-01-01

    Recurrent stress has been found to impair brain structures essential to memory. The cognitive reserve model suggests that physical activity supplies protection against memory decline in neuropathologies. The purpose of the present study was to explore whether leisure physical activity modifies the predicted negative effect stress has on memory. A sub-sample derived from the Betula Study comprised 267 participants between 50 and 65 years. Memory was assessed by a SPT free recall and stress by ...

  5. Assessing the Effect of Leaf Litter Diversity on the Decomposition and Associated Diversity of Fungal Assemblages

    OpenAIRE

    Jing Gao; Fengfeng Kang; Tianyu Li; Xiaoshuai Song; Weihong Zhao; Xiaowen Yu; Hairong Han

    2015-01-01

    Although the effect of litter mixture on decomposition has been well documented, few studies have examined the relationships between richness and relative abundance of leaf species in litter mixture and changes in universal fungal communities during the decomposition process in temperate forests. In this study, we used the litterbag method and included three leaf litter species, i.e., aspen (Populus davidiana Dode), birch (Betula platyphylla Sukaczev) and oak (Quercus mongolica Fischer ex Led...

  6. Foliar Litter Nitrogen Dynamics as Affected by Forest Gap in the Alpine Forest of Eastern Tibet Plateau

    OpenAIRE

    Wu, Qiqian; Wu, Fuzhong; Yang, Wanqin; Zhao, Yeyi; Wei HE; Tan, Bo

    2014-01-01

    There is increasing attention on the effects of seasonal snowpack on wintertime litter decomposition, as well as the processes following it, in cold biomes. However, little information is available on how litter nitrogen (N) dynamics vary with snowpack variations created by tree crown canopies in alpine forests. Therefore, to understand the effects of seasonal snowpack on litter N dynamics during different critical stages, litterbags with fir (Abies faxoniana), birch (Betula albo-sinensis), l...

  7. Fungi are involved in the effects of litter mixtures on consumption by shredders

    OpenAIRE

    Jabiol, Jérémy; Chauvet, Eric

    2012-01-01

    1. Decomposition of litter mixtures in both terrestrial and aquatic ecosystems often shows non- additive diversity effects on decomposition rate, generally interpreted in streams as a result of the feeding activity of macroinvertebrates. The extent to which fungal assemblages on mixed litter may influence consumption by macroinvertebrates remains unknown. 2. We assessed the effect of litter mixing on all possible three-species combinations drawn from four tree species (Alnus glutinosa, Betula...

  8. Investigation of the antioxidant properties of five aromatic plants in model food systems

    OpenAIRE

    Azman, Nurul Aini Binti Mohd

    2015-01-01

    In this PhD it has been analyzed the antioxidant activity of five plants: Camelia sinensis, Gentian lutea, Betula pendula, Convolvulus arvensis and Arctostaphylos uva-ursi. An Electronic Paramagnetic Resonance has been tuned up to determine the antiradical activity of white tea against the methoxy radical using ferulic acid as a standard. It has been proven that the components with more antiradical activity, against the methoxy radical, are the ones with the gallate group, EGCG and ECG. ...

  9. Diabetes and cognitive functioning : The role of age and comorbidity

    OpenAIRE

    Nilsson, Erik

    2006-01-01

    This thesis deals with the influence of type 2 diabetes on cognitive function in adulthood and very old age. The effects of diabetes are studied both in populations free from dementia, and in a clinical Alzheimer's disease population. For Studies 1 & 11, a non-demented, non-depressed, sample of very old (>75 years of age) persons from the Kungsholmen Project in Stockholm, Sweden, was used. For Study Ill, data from the Betula prospective cohort study were employed. All select...

  10. Pulse Pressure magnifies the effect of COMT Val158Met on 15 Year Episodic Memory Trajectories

    OpenAIRE

    Persson, Ninni; Lavebratt, Catharina; Sundström, Anna; Fischer, Håkan

    2016-01-01

    We investigated whether a physiological marker of cardiovascular health, pulse pressure (PP), and age magnified the effect of the functional COMT Val158Met (rs4680) polymorphism on 15-years cognitive trajectories [episodic memory (EM), visuospatial ability, and semantic memory] using data from 1585 non-demented adults from the Betula study. A multiple-group latent growth curve model was specified to gauge individual differences in change, and average trends therein. The allelic variants showe...

  11. Birch pollen allergy: molecular characterization and hypoallergenic products

    OpenAIRE

    Schenk, M.F.

    2008-01-01

    Allergic diseases, such as hay fever and food allergy, affect a substantial part of the population in westernized countries. Pollen of the European white birch (Betula pendula) is a considerable cause of hay fever (seasonal allergic rhinitis) in northern and central Europe. The major birch pollen allergen is Bet ν 1, which is the conventional allergen name for the birch pollen proteins of a large group of proteins otherwise known as PR-10 proteins. Individuals that suffer from birch pollen al...

  12. Wild Collection and Cultivation of Native Species in Iceland

    OpenAIRE

    Whitney, Cory; Gebauer, Jens; Anderson, Molly

    2014-01-01

    Based on an MSc thesis submitted to the joint Master program between University of Kassel and University of Goettingen and later published: WHITNEY C.W., GEBAUER J. & ANDERSON M. 2012. A Survey of Wild Collection and Cultivation of Indigenous Species in Iceland. Human Ecology. This paper outlines a survey of Icelanders who use local plants. Some of the species (e.g. Angelica spp. and Betula spp.) were very important. However, great potential exists for a more diverse harvest and for sust...

  13. Plant secondary compounds and soil microbial processes in carbon and nitrogen cycling in relation to tree species

    OpenAIRE

    Kanerva, Sanna

    2007-01-01

    The aim of this study was to explore soil microbial activities related to C and N cycling and the occurrence and concentrations of two important groups of plant secondary compounds, terpenes and phenolic compounds, under silver birch (Betula pendula Roth), Norway spruce (Picea abies (L.) Karst) and Scots pine (Pinus sylvestris L.) as well as to study the effects of volatile monoterpenes and tannins on soil microbial activities. The study site, located in Kivalo, northern Finland, included ca....

  14. Speciation of Mg, Mn and Zn in extracts of medicinal plants

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Guenther [Institute of Spectrochemistry and Applied Spectroscopy, Bunsen-Kirchhoff-Str. 11, 44139, Dortmund (Germany); Konieczynski, Pawel [Department of Analytical Chemistry, Medical University of Gdansk, ul. Hallera 107, 80-416, Gdansk (Poland)

    2003-04-01

    Aqueous extracts of birch leaves (folium Betulae), peppermint leaves (folium Menthae), sage leaves (folium Salviae), valerian roots (radix Valerianae), and dandelion roots (radix Taraxaci) are analysed for the three essential elements magnesium, manganese and zinc. Ultrafiltration reveals that 60-100% of these metals are present as low molecular weight species (<5000 Da). Further characterisation of the low molecular weight fraction is done by using size exclusion chromatography and different detectors, namely element specific AAS detection, diode array UV-VIS detection and electrochemical detection. The similarities and differences of the plant extracts are well reflected by the respective chromatograms, and typical plant constituents can be identified by their spectral and electrochemical properties (e.g. flavonoids in Betula). Mg and Mn species are selectively detected by AAS in closely neighbouring chromatographic regions for all five samples. However, there are significant differences between the samples investigated. In all cases a good correlation exists between detection of these metals (Mg, Mn) and pulsed amperometric detection (PAD), which is selective for carbohydrates. The respective molecular weight of carbohydrate species is in the range of approximately 300-600 Da. The distribution of zinc species (detectable only in the Betula extract) is totally different from that of Mg and Mn species. For zinc, many more species are detected, and there is no correlation to carbohydrates; instead (poly)phenols are involved in zinc complexation. (orig.)

  15. Survival and growth for pubescent birch, pendula birch and common alder growing on farmland areas; Oeverlevnad och tillvaext hos glasbjoerk, vaartbjoerk och klibbal planterade paa aakermark

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Tord

    2000-07-01

    Pendula birches (Betula pendula Roth) and pubescent birches (Betula pubescens Ehrh.) were planted on former farmland. Before planting, the ground was harrowed or the ground was sprayed with terbuthylazine. Tree shelters were used as protection against weeds, voles and wild habitat. Birches treated with terbuthylazine showed the lowest survival. Birches growing in tree shelters were tallest and those growing on spots treated with terbuthylazine were smallest. The diameter at 0.1 m did not differ in a statistically significant way between the treatments. In another experiment with different herbicides, common alder (Alnus glutinosa (L.) Gaertn.) and pendula birch (Betula pendula Roth) were planted on former farmland that had been treated with glyphosate, terbuthylazine and propyzamide or after ground had been harrowed or not treated. In the study on herbicide-treated plants, birch had the highest plant survival. Mostly, species treated with glyphosate were thicker than species treated in other ways. Both species appeared sensitive to terbuthylazine, but not to glyphosate. Birch was not sensitive for propyzamide in opposite to alder. Some practical recommendations concerning afforestation of former farmland, especially weeding, are given.

  16. БИОХИМИЧЕСКИЕ ОСОБЕННОСТИ КОНСТИТУТИВНОЙ РЕЗИСТЕНТНОСТИ БЕРЕЗЫ ПОВИСЛОЙ (BETULA PENDULA ROTH. ) К ПОВРЕЖДЕНИЮ НАСЕКОМЫМИ-ФИЛЛОФАГАМИ В УСЛОВИЯХ АНТРОПОГЕННОГО ВОЗДЕЙСТВИЯ

    OpenAIRE

    Колтунов, Е. В.; ЯКОВЛЕВА М.И.

    2014-01-01

    Проведено изучение биохимических факторов природной (конститутивной) энтоморезистентности из листьев березы повислой из затухших очагов непарного шелкопряда и за их границами. Хроматографический анализ (ВЭЖХ) выявил 51-54 фенольных соединения. В образцах за границами очагов выявлено преобладание фенольных соединений с заметным возрастанием содержания в пике (38,9%), по сравнению с контролем (образцы из очагов). В их составе флавоноиды, фенолгликозиды, фенолкарбоновые кислоты. В составе фенолг...

  17. ВЛИЯНИЕ ТЕХНОГЕННОГО ЗАГРЯЗНЕНИЯ НА СОДЕРЖАНИЕ ФЕНОЛЬНЫХ СОЕДИНЕНИЙ В ЛИСТЬЯХ БЕРЕЗЫ ПОВИСЛОЙ (BETULA PENDULA ROTH.) В УСЛОВИЯХ УРБАНИЗАЦИИ

    OpenAIRE

    ШАВНИН С.А.; Колтунов, Е. В.; ЯКОВЛЕВА М.И.

    2014-01-01

    Хроматографический анализ фенольных соединений из листьев березы повислой в условиях урбанизации на разном расстоянии от городской автомагистрали выявил 51-54 соединения. Из общего количества идентифицировано 15 фенольных соединений (флавоноиды, фенолкарбоновые и гидроксикоричные кислоты). Попарный сравнительный анализ образцов из листьев деревьев вблизи автомагистрали показал значительное преобладание фракций со снижением содержания соединений (68,18%). Возрастание содержания фенольных соеди...

  18. Holocene Asian monsoon evolution revealed by a pollen record from an alpine lake on the southeastern margin of the Qinghai-Tibetan Plateau, China

    Science.gov (United States)

    Zhang, Enlou; Wang, Yongbo; Sun, Weiwei; Shen, Ji

    2016-02-01

    We present the results of pollen analyses from a 1105 cm long sediment core from Wuxu Lake in southwestern China, which depict the variations of the East Asian winter monsoon (EAWM) and the Indian summer monsoon (ISM) during the last 12.3 ka. During the period of 12.3 to 11.3 cal ka BP, the dominance of Betula forest and open alpine shrub and meadow around Wuxu Lake indicates a climate with relatively cold winters and dry summers, corresponding to the Younger Dryas event. Between 11.3 and 10.4 cal ka BP, further expansion of Betula forest and the retreat of alpine shrubs and meadows reflect a greater seasonality with cold winters and gradually increasing summer precipitation. From 10.4 to 4.9 cal ka BP, the dense forest understory, together with the gradual decrease in Betula forest and increase in Tsuga forest, suggest that the winters became warmer and summer precipitation was at a maximum, corresponding to the Holocene climatic optimum. Between 4.9 and 2.6 cal ka BP, Tsuga forest and alpine shrubs and meadows expanded significantly, reflecting relatively warm winters and decreased summer precipitation. Since 2.6 cal ka BP, reforestation around Wuxu Lake indicates a renewed humid period in the late Holocene; however, the vegetation in the catchment may also have been affected by grazing activity during this period. The results of our study are generally consistent with previous findings; however, the timing and duration of the Holocene climatic optimum from different records are inconsistent, reflecting real contrast in local rainfall response to the ISM. Overall, the EAWM is broadly in-phase with the ISM on the orbital timescale, and both monsoons exhibit a trend of decreasing strength from the early to late Holocene, reflecting the interplay of solar insolation receipt between the winter and summer seasons and El Niño-Southern Oscillation strength in the tropical Pacific.

  19. Vegetation response to climate forcing during the last glacial maximum and deglaciation in the East Carpathians: attenuated response to maximum cooling and increased biomass burning

    Directory of Open Access Journals (Sweden)

    Eniko M. MAGYARI

    2014-11-01

    Full Text Available The Carpathian Mountains were one of the main mountain reserves of the boreal and cool temperate flora during the Last Glacial Maximum (LGM in East-Central Europe. Previous studies demonstrated late glacial vegetation dynamics in this area; however, our knowledge on the LGM vegetation composition is limited due to the scarcity of suitable sedimentary archives. Here we present a new record of vegetation, fire and lacustrine sedimentation from the youngest volcanic crater of the Carpathians (Lake St Anne, Lacul Sfânta Ana, Szent-Anna-tó to examine environmental change in this region during the LGM and the subsequent deglaciation. Our record indicates the persistence of boreal forest steppe vegetation (Pinus sylvestris, Pinus mugo, Pinus cembra, Betula, Salix, Populus, Picea abies in the foreland and low mountain zone of the East Carpathians and Juniperus shrubland at higher elevation. We demonstrate attenuated response of the regional vegetation to maximum global cooling. Between ~22,870 and 19,150 cal yr BP we find increased regional biomass burning that is antagonistic with the global trend. Increased regional fire activity suggests extreme continentality likely with relatively warm and dry summers. We also demonstratexerophytic steppe expansion directly after the LGM, from ~19,150 cal yr BP, and regional increase in boreal woodland cover with Pinus and Betula from 16,300 cal yr BP. Plant macrofossils indicate local (950 m a.s.l. establishment of Betula nana and B. pubescens at 15,150 cal yr BP, Pinus sylvestris at 14,700 cal yr BP and Larix decidua at 12,870 cal yr BP. Pollen data furthermore hints at the regional presence of some temperate deciduous trees during the LGM (Fagus sylvatica, Carpinus betulus, Corylus avellana, Fraxinus excelsior, Ulmus. We also present pollen based quantitative climate reconstruction from this site and discuss its connection with other climate reconstructions and climate modeling results. 

  20. Plant pollen content in the air of Lublin (central-eastern Poland and risk of pollen allergy

    Directory of Open Access Journals (Sweden)

    Krystyna Piotrowska-Weryszko

    2014-11-01

    Full Text Available Pollen monitoring was carried out in Lublin in 2001–2012 by the volumetric method using a Hirst-type spore trap (Lanzoni VPPS 2000. Daily pollen concentrations considerably differed in the particular years. The pollen counts with the biggest variability were observed in the first half of a year when woody plants flowering. The highest annual pollen index were noted for the following taxa: [i]Betula, Urtica,[/i] Pinaceae, Poaceae and [i]Alnus[/i]. [i]Betula[/i] annual total showed the greatest diversity in the study years. The number of days on which the pollen concentration exceeded the threshold values, thereby inducing allergies, was determined for the taxa producing the most allergenic pollen. The above-mentioned taxa primarily included the following: Poaceae, in the case of which the highest number of days with the risk of occurrence of pollen allergy was found (35, [i]Betula[/i] (18, and [i]Artemisia[/i] (10. The following taxa:[i] Alnus[/i] (14 days, [i]Populus[/i] (11 days, [i]Fraxinus[/i] (10 days, and [i]Quercus[/i] (8 days, were also characterized by a large number of days on which their pollen concentrations exceeded the threshold values. The occurrence of periods of high concentration of particular pollen types were also noted. Risk of pollen allergy appeared the earliest at the beginning of February during [i]Alnus [/i]and [i]Corylus[/i] blooming. High concentrations of other woody plants were recorded from the last ten days of March to about 20 May, and of herbaceous plants from the first/last half of May – beginning of October.

  1. The phenological phases of flowering and pollen seasons of spring flowering tree taxa against a background of meteorological conditions in Kraków, Poland

    Directory of Open Access Journals (Sweden)

    Danuta Stępalska

    2016-06-01

    Full Text Available The aim of the study was to compare phenological observations of pollen seasons of selected early spring trees. Special attention was paid to meteorological conditions which favored or did not favor tree flowering and pollen release. For this reason, we used phenological observation, pollen counts, and meteorological data in five sites in the center of Kraków in the period 2009–2011. Phenological phases (5 of four tree species: Alnus glutinosa, Alnus incana, Corylus avellana, and Betula pendula, were analyzed. It was found that in case of A. glutinosa the pollen season often preceded the flowering period, while for A. incana those two phenomena were more correlated. As regards Corylus avellana, the beginning of the pollen season and phenological phases was simultaneous. However, pollen grains occurred in the air longer, even by a dozen or so days. The phenological phases and pollen seasons of Alnus and Corylus were dependent on meteorological conditions. To give the definition of the relationship between pollen concentration and weather conditions, Spearman rank correlation analysis was applied. High Alnus and Corylus pollen concentrations were found on sunny days with a maximum temperature over 10°C and no precipitation, and when the snow cover was gone. In case of Betula, the phenological phases of the full pollination period usually coincided with the periods of high pollen concentrations. However, Betula pollen sometimes appears earlier and stays in the air longer than the flowering period of local trees in the nearest vicinity. This situation indicates long-distance transport or secondary deposition.

  2. Stature of Sub-arctic Birch in Relation to Growth Rate, Lifespan and Tree Form

    OpenAIRE

    JÓNSSON, THORBERGUR HJALTI

    2004-01-01

    • Background and Aims Sub-arctic mountain birch Betula pubescens var. pumila communities in the North Atlantic region are of variable stature, ranging from prostrate scrubs to forests with trees up to 12 m high. Four hypotheses were tested, relating growth and population characteristics of sub-arctic birch woodland and scrub to tree stature; i.e. the variable stature of birch woods is due to differences in (1) the mean growth rate; (2) the age-related patterns of growth rate; (3) the life exp...

  3. Environmentally friendly utilization of biomass

    OpenAIRE

    Grimm, Alejandro

    2007-01-01

    The thesis deals with various ways of utilization of biomass. Chapter 1 compares three biomass types: birch wood Betula sp., marine brown alga Fucus vesiculosus, and terrestrial moss Pleurozium schreberi, as precursors for preparation of biosorbents for removal of copper ions from diluted water solutions. Small sample doses (0.5 g/100ml) of the biosorbents prepared from alga and moss enabled more than 90 % removal of Cu (II) ions from diluted water solutions (5-20 mg/l). The sample from birch...

  4. Fuelwood characteristics of selected indigenous tree species from central India

    Energy Technology Data Exchange (ETDEWEB)

    Jain, R.K.; Singh, B. [National Botanical Research Institute, Lucknow (India)

    1999-06-01

    Thirty tree species indigenously growing in their natural habitat in subtropical forest of central India were collected and fuelwood properties viz, moisture, silica, ash, density, carbon, nitrogen, volatile matter, calorific value and fuel value index (FVI) calculated to screen desirable species for potential production of fuelwood in these areas. The present study revealed that Acer oblongum, Betula alonoides, Grevillea robusta, Limonia acidissima, Lyonia ovalifolia, Madhuca indica, Melia azedarch, Morinda tinctoria, Myrica sapida, Prunus cornuta, Pyrus pashia, Quercus langinosa, Rhamnus triqueter and Stereospermum xylocarpum possess excellent fuelwood qualities. (Author)

  5. Biomass distribution patterns of ecotones between forest and swamp in Changbai Mountain

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper studied the biomass distribution patterns of Larix olgensis/swamp ecotones and Betula platyphlla/swamp ecotones in Changbai Mountain so as to provide theory foundation for the management of these nature resources, by setting up sample belts, investigating initial data along the environmental gradients change, and establishing regression models. By means of regression models, the biomass of communities, layers, tree species and organs was calculated. In this system, it was found that the community biomass increased gradually along the environmental gradients change from swamp to forest in Changbai Mountain. Furthermore, the ecotoneal biomass distributed mainly over tree layer. The tree biomass distributed mainly in two or three dominate tree species.

  6. Development of Bioavailable Pools of Base Cations and P after Afforestation of Volcanic Soils in Iceland

    DEFF Research Database (Denmark)

    Ritter, Eva

    2009-01-01

    Few long-term studies have been conducted on changes in soil nutrients after afforestation in Iceland, a country with a young history of forest management. While fertilization was shown to improve survival of seedlings in the first years after planting on the nutrient limited soils, knowledge about......): native birch (Betula pubescens) and introduced Siberian larch (Larix sibirica). A treeless heathland was included to present soil conditions prior to forest establishment. The sites are part of the largest forest area in Iceland, located in the east of the country. Results revealed an effect of stand age...

  7. Effect of Tree Species and Mycorrhizal Colonization on the Archaeal Population of Boreal Forest Rhizospheres▿

    OpenAIRE

    Bomberg, Malin; Timonen, Sari

    2008-01-01

    Group 1.1c Crenarchaeota are the predominating archaeal group in acidic boreal forest soils. In this study, we show that the detection frequency of 1.1c crenarchaeotal 16S rRNA genes in the rhizospheres of the boreal forest trees increased following colonization by the ectomycorrhizal fungus Paxillus involutus. This effect was very clear in the fine roots of Pinus sylvestris, Picea abies, and Betula pendula, the most common forest trees in Finland. The nonmycorrhizal fine roots had a clearly ...

  8. Inhibition of the growth of Alexandrium tamarense by algicidal substances in Chinese fir (Cunninghamia lanceolata).

    Science.gov (United States)

    Yang, Wei-Dong; Liu, Jie-Sheng; Li, Hong-Ye; Zhang, Xin-Lian; Qi, Yu-Zao

    2009-10-01

    The wood sawdust from Chinese fir (Cunninghamia lanceolata) exhibited stronger inhibition on the growth of Alexandrium tamarense than those from alder (Alnus cremastogyne), pine (Pinus massoniana), birch (Betula alnoides) and sapele (Entandrophragma cylindricum). The water extract, acetone-water extract and essential oil from fir sawdust were all shown to inhibit the growth of A. tamarense. The inhibition of fir essential oil was the strongest among all the above wood sources while the half effective concentration was only 0.65 mg/L. These results suggested that the fir essential oil may play an important role in the algicidal effect of Chinese fir. PMID:19634014

  9. A 22 570 yr record of vegetational and climatic change from Wenhai Lake in the Hengduan Mountains biodiversity hotspot, Yunnan, Southwest China

    Directory of Open Access Journals (Sweden)

    Y. F. Yao

    2014-09-01

    Pinus and Abies, coupled with broad-leaved forest (mainly Quercus and Betula, reflecting a transition in climatic conditions from warm-humid to cold-humid. During this period, human activity increased in this region, with impacts on the vegetation which may be evidenced by the distinct decrease in Pinus and Quercus pollen and an increase in Polygonaceae pollen in the upper 30 cm of the core. The marked decline in Quercus pollen, in particular, in the Wenhai core can be correlated with that observed in the Haligu core (situated about 2 km away between 2400 cal. yr BP and the present.

  10. Biomass functions for young scots pine-dominated forest

    Energy Technology Data Exchange (ETDEWEB)

    Ahnlund Ulvcrona, K. (Vindeln Experimental Forests, Svartberet Research Station, Swedish Univ. of Agricultural Science, Vindeln (Sweden)), e-mail: Kristina.ulvcrona@esf.slu.se; Nilsson, U. (Southern Swedish Forest Research centre, Swedish Univ. of Agricultural Science, Alnarp (Sweden)); Lundmark, T. (Forest Ecology and Management, Swedish Univ. of Agricultural Science, Umeaa (Sweden))

    2010-07-15

    The aim of this study was to develop predictive biomass functions for young stands of Scots pine-dominated forests in northern Sweden. Above ground biomass was destructively sampled, and biomass functions for all tree fractions (e.g. stem including bark, branch and foliage) were developed, based on independent variables. Functions to estimate dry weight of the whole tree were also developed. No significant regressions could be found for the dead branch fraction. DBH for sampled trees in this study was in the range of 11 - 136 mm (Pinus sylvestris), 10 - 121 mm (Picea abies L. Karst) and 9 - 113 mm (Betula spp.)

  11. Arboristični vidiki snegoloma v mestni občini Ljubljana v zimi 1999:

    OpenAIRE

    Marion, Lena; Oven, Primož; Torelli, Niko

    2005-01-01

    As a result of heavy snow in February 1999, trees were damaged in the City of Ljubljana, Slovenia. Of the investigated 624 trees, 195 (31%) were damaged by snow. On average, 1.7 branch and top per tree were broken. Snow damaged 17 tree species, affecting particularly Aesculus hippocastanum L. and, to a lesser extent, Betula pendula ROTH. and Salix x sepulcralis SIMONK. Decay was the most frequent defect at the failure location and was often associated withincluded bark and vicinity of old mec...

  12. Analysis of trees planted in vicinity of hospitals in Ljubljana as a source of pollen

    OpenAIRE

    Kofol Seliger, Andreja; Pirnat, Janez

    2010-01-01

    The paper analyses woody plants growing in the vicinity of hospital buildings situated along Zalog Road, Korytko Street, Šlajmar Street, Bohorič Street and Njegoš Street in Ljubljana, Slovenia. Woody plants are an immediate potential source of allergenic pollen, affecting all park users such as patients, visitors and hospital employees. The most allergenic tree species in the park was found to be birch (Betula pendula Roth.), which accounts for 6.8% of all registered trees. The low allergenic...

  13. Air pollution and the respiration of certain tree species

    Energy Technology Data Exchange (ETDEWEB)

    Makedonska, T.; Slavova, V.

    1973-01-01

    These studies are conducted to compare the effects of air pollution on horse chestnut (Aesculus hippocastanum L.), London plane (Platanus acerifolia Milld.) ash-leaved maple (Acer negundo L.) and European birch (Betula alba L.). With increasing concentrations of air pollution these species react by increasing the intensity of respiration, as in separate cases the increase reaches up to 40%. Most sensitive to air pollution is the horse chestnut, followed by birch and ash-leaved maple; least sensitive is London plane. With respect to gas resistance birch and ash-leaved maple rank close to the horse chestnut but are more resistant than the horse chestnut and less sensitive than London plane.

  14. rboricultural aspects of snow-damage in the citz of Ljubljana in the winter 1999

    OpenAIRE

    Marion, Leon; Torelli, Niko; Oven, Primož

    2005-01-01

    As a result of heavy snow in February 1999, trees were damaged in the City of Ljubljana, Slovenia. Of the investigated 624 trees, 195 (31%) were damaged by snow. On average, 1.7 branch and top per tree were broken. Snow damaged 17 tree species, affecting particularly Aesculus hippocastanum L. and, to a lesser extent, Betula pendula ROTH. and Salix x sepulcralis SIMONK. Decay was the most frequent defect at the failure location and was often associated withincluded bark and vicinity of old mec...

  15. PURIFICATION OF HARDWOOD-DERIVED AUTOHYDROLYSATES

    OpenAIRE

    Joni Tapani Lehto,; Raimo Juhani Alén

    2012-01-01

    Carbohydrate-containing hydrolysates (1.1 to 14.9% of wood dry matter) obtained from autohydrolysis (at 130 to 150°C for 30 to 120 minutes) of birch (Betula pendula) chips prior to pulping were purified with respect to non-carbohydrate materials, without carbohydrate losses, either by ethyl acetate extraction or XAD-4 resin treatment. In the former case, about 50% of lignin and practically all the furanoic compounds (2-furaldehyde and 5-(hydroxymethyl)furfural) could be removed, whereas in th...

  16. Pollen record and environmental evolution of Caotanhu wetland in Xinjiang since 4550 cal. a BP

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yun; KONG ZhaoChen; NI Jian; YAN Shun; YANG ZhenJing

    2008-01-01

    This paper presents a multi-proxy reconstruction of the climate change in Caotanhu wetland using pollen, phytolith and charcoal records, and the data of loss of ignition (LOI), grain size analysis, and susceptibility. Results reveal that between 4550 and 2500 cal. a BP, a dry climatic condition was not favorable for the accumulation of peat. Since 2500 cal. a BP, the climate became humid and the wetland developed with abundant freshwater aquatic plants, which contributed to peat accumulation. Never-theless, alternate periods of rain and dry climate occurred during that period. Between 2500 and 1810 cal. a BP (550 BC-140 AD), the climate was more humid than at present. A lot of emerged plants, such as Phragmites, Typha and Sparganium, and freshwater green algae grew in the wetland which was sur-rounded by desert-steppe vegetation composed mainly of Chenopodiaceae, Arternisia, Compositae and Thalictrum. However, from 1810 to 1160 cal. a BP (140-790 AD), the water level started to decrease and hydrophyte species reduced greatly, but some Phragmites still grew in the wetland and around it was desert vegetation with high proportion of Chenopodiaceae and Artemisia. Then from 1160 to 650 a BP (790-1300 AD), it entered a period of desert-steppe with abundant mesic and xerophytic plants. And a lot of aquatic plants prevailed in the wetland. Here, what is noticeable is that percentages of arboreal pollen, consisting mainly of Betula and Picea, increased greatly and reached a maximal value of 27.2%, in which, Betula percentages rose to 23.2%. Hence, it is reasonable to conclude that Betula grew in the highland of the wetland, or Picea timberline shifted downward resulting in the increase of percentages of Betula and Picea pollen, which were transported into the wetland by flood or wind. But since 650 cal. a BP, desert vegetation prevailed around the wetland again with dominant Chenopodiaceae and Ar-temisia, and the climate was similar to modern one. Despite some aquatic

  17. How to measure distinct components of visual attention fast and reliably

    DEFF Research Database (Denmark)

    Vangkilde, Signe Allerup; Kyllingsbæk, Søren; Habekost, Thomas; Bundesen, Claus; Marklund, Petter; Nilsson, Lars-Göran

    2009-01-01

    the Swedish Betula-project, a longitudinal study investigating changes in cognitive functions over the adult life span (Nilsson et al., 2004). The test consists of a computer-based letter recognition task with stimulus displays of varied durations followed by pattern masks or a blank screen. The......Measuring different attentional processes in a fast and reliable way is important in both clinical and experimental settings. However, most tests of visual attention are either lengthy or lack sensitivity, specificity, and reliability. To address this we developed a ten minute test procedure for...

  18. Application of calibration standardization method to the analysis of diuretic pharmaceutical herbs

    International Nuclear Information System (INIS)

    Calibration standardization of X-ray fluorescence method was carried out for the determination of the anorganic contents in diuretic herbs as called Folia Betulae, Stylus Maydis, Flores Verbasci, Equisetum Arvense and Flos Helichrysi, growing in Turkey. These herbs are widely used in pharmacy and public health for kidney disease therapy. Herb samples were steeped in the water and mixed through the pure cellulose, then pelletized in the intermediate thickness. An annular source of 109Cd (3.7 MBq) was used for excitation of fluorescent K lines of elements lying between potassium and zirconium. Toxic elements in considerable amounts were not found. (author)

  19. Hoitotyön vaikutus nuoren visakoivikon metsikön arvoon

    OpenAIRE

    Siipola, Simo

    2012-01-01

    Tämän tutkimuksen tavoitteena oli selvittää nuorten visakoivikoiden (Betula pentula var. carelica) arvoa tilavuuden funktiona. Nuorten visakoivikoiden tilavuus-arvonmäärityksiä tarvitaan esimerkiksi metsikön maanlunastuksissa, tilakaupoissa, tila-arvioinneissa ja erilaisissa korvausasioissa. Visaseura ry:n 2010 jäsenilleen järjestämässä nuorten visakoivikoiden kyselyssä; Har-vennusikäisten visojen kasvattaminen, etsittiin nuoria ja varttuneempia visakoivikoita tutkimustyöhön. Suunnitelman...

  20. Contribución al conocimiento de agaricales y russulales de los Pirineos aragoneses (Valles de Ordesa y Pineta-Huesca).

    OpenAIRE

    CASTRO CERCEDA, M.L., FREIRE, L.

    1991-01-01

    En este trabajo enumeramos unas 40 especies de macromicetos,   pertenecientes a los órdenes Agaricales y Russulales, que fueron   encontrados por los autores, durante el otoño de 1989, en la II   Campaña de Microflora Ibérica. Las especies han sido recolectadas preferentemente en bosques   mixtos de hayas (Fagus sylvativa) y abetos (Abies alba) con   extraordinario sotobosque de boj (Buxus sempervirens), pero   también fueron visitados abedulares (Betula sp.) y prados. ...

  1. AGING AND DECISION MAKING AS MEASURED BY THE SWEDISH VERSION OF THE ADMC BATTERY

    OpenAIRE

    jaafar hussein, amez

    2013-01-01

    The aim of this study was to examine age-related differences in decision-making competence. The study is a part of the ongoing Betula project (Nilsson et al., 1997; 2004), and the data included test results from (N, 364) corresponding to the questionnaires with complete responses (>80%) to the items addressed. The Swedish version of the Adult Decision-Making Competence (A-DMC) battery was used. An exploratory factor analysis of the A-DMC data yielded a two-component solution: The A-DMC tas...

  2. Flora vascular acompañante en masas de monte bajo de castaño en Asturias

    OpenAIRE

    García, Andrés; Díaz-, T.; Majada, Juan; Ciordia, Marta

    2014-01-01

    En Asturias, las zonas forestales ocupan un total de 762.329 hectáreas, es decir, el 72,2% de la superficie del Principado es monte. De éstas, 453.700 hectáreas son arboladas, siendo los bosques de caducifolios (hoja caduca) los más abundantes y que representan en torno al 20% de la superficie asturiana. En estos bosques encontramos, por ejemplo, especies arbóreas como el roble (Quercus spp.), el abedul (Betula celtiberica Rothm. & Vasc.) o el haya (Fagus sylv...

  3. Vegetation and climate history in the Laptev Sea region (Arctic Siberia) during Late Quaternary inferred from pollen records

    Science.gov (United States)

    Andreev, Andrei A.; Schirrmeister, Lutz; Tarasov, Pavel E.; Ganopolski, Andrey; Brovkin, Viktor; Siegert, Christine; Wetterich, Sebastian; Hubberten, Hans-Wolfgang

    2011-08-01

    Paleoenvironmental records from a number of permafrost sections and lacustrine cores from the Laptev Sea region dated by several methods ( 14C-AMS, TL, IRSL, OSL and 230Th/U) were analyzed for pollen and palynomorphs. The records reveal the environmental history for the last ca 200 kyr. For interglacial pollen spectra, quantitative temperature values were estimated using the best modern analogue method. Sparse grass-sedge vegetation indicating arctic desert environmental conditions existed prior to 200 kyr ago. Dense, wet grass-sedge tundra habitats dominated during an interstadial ca 200-190 kyr ago, reflecting warmer and wetter summers than before. Sparser vegetation communities point to much more severe stadial conditions ca 190-130 kyr ago. Open grass and Artemisia communities with shrub stands ( Alnus fruticosa, Salix, Betula nana) in more protected and moister places characterized the beginning of the Last Interglacial indicate climate conditions similar to present. Shrub tundra ( Alnus fruticosa and Betula nana) dominated during the middle Eemian climatic optimum, when summer temperatures were 4-5 °C higher than today. Early-Weichselian sparse grass-sedge dominated vegetation indicates climate conditions colder and dryer than in the previous interval. Middle Weichselian Interstadial records indicate moister and warmer climate conditions, for example, in the interval 40-32 kyr BP Salix was present within dense, grass-sedge dominated vegetation. Sedge-grass- Artemisia-communities indicate that climate became cooler and drier after 30 kyr BP, and cold, dry conditions characterized the Late Weichselian, ca 26-16 kyr BP, when grass-dominated communities with Caryophyllaceae, Asteraceae, Cichoriaceae, Selaginella rupestris were present. From 16 to 12 kyr BP, grass-sedge communities with Caryophyllaceae, Asteraceae, and Cichoriaceae indicate climate was significantly warmer and moister than during the previous interval. The presence of Salix and Betula reflect

  4. Molecular responses of plants to solar UV-B and UV-A radiation

    OpenAIRE

    Morales Suárez, Luis Orlando

    2014-01-01

    Plant responses to solar ultraviolet radiation (UV, 280-400 nm) were assessed at different molecular levels using Betula pendula Roth (silver birch) and Arabidopsis thaliana (Arabidopsis) as model species in outdoor experiments to assess the possibly interacting roles of the UV-B and UV-A wavebands in acclimation to sunlight. Solar UV-B (280-315 nm) and UV-A (315-400 nm) irradiance was attenuated with plastic films. Both solar UV-B and UV-A promoted the acclimation of silver birch and Arabido...

  5. Spoil heaps from brown-coal mining in NW Bohemia: spontaneous succession vs reclamation

    International Nuclear Information System (INIS)

    Some results, conclusions and suggestions are presented that emerged from the study on spontaneous succession which started in 1977. Trends in spontaneous succession are briefly described. Under certain conditions, spontaneous succession is the cheapest reclamation method. On marginal heap slopes, tree planting is recommended as the most rapid reclamation measure. The expansion of grasses and trees can be accelerated by their artificial sowing or planting. Arrhena therum elatius seems to be the most suitable among grasses, and Betula verrucosa among woody species to be sown and then successfully established. The best time is usually between the 6th and 10th years of spontaneous succession. (Z.S.) 1 fig., 4 refs

  6. Comparative analysis of species-based specificity in Sz90 and Cs137 accumulation demonstrated by ligneous plant forest communities

    International Nuclear Information System (INIS)

    Field-proven study of Sr90 and Cs137 absorption activity demonstrated by pinus silvestris l., piceae abies (l) roth, quercus rubra l., acer platanoides l., betula pendula roth., tilia cordata mill. under identical habitat conditions. The above plants were examined after 5-year growth period on radionuclide-contaminated soil. To a great extent, such parameters as radionuclide accumulation in experimental plants and accumulation activity were determined by the plants' bio-ecological properties. Differences relevant to these parameters could reach 15-fold value

  7. Retranslocation of foliar nutrients of deciduous tree seedlings in different soil condition under free-air O3 enrichment

    OpenAIRE

    Shi C; Eguchi N; Meng F; Watanabe T.; Satoh F; Koike T.

    2016-01-01

    Retranslocation is the amount of an element that is depleted from old plant components and is provided for new growth. Leaf senescence is usually accelerated at elevated O3 (eO3), and leaf shedding is influenced by soil nutrient availability (and acidification). In this study, we focused on the net retranslocation and allocation dynamics of foliar nutrients (N, P, Mg, K, Ca, Mn, Fe and Al) to investigate the effect of eO3 on birch (Betula platyphylla var. japonica), oak (Quercus mongolica var...

  8. The biochemical and histoanatomical response of some woody species to anthropic impact in Suceava County, Romania

    OpenAIRE

    Elena CIORNEA; Irina BOZ; IONEL, ELENA; COJOCARU, SABINA IOANA; DUMITRU, Gabriela

    2015-01-01

    The use of extractive mining technologies in various areas of Suceava, Romania (C?limani Mountains - sulfur, Tarni?a-Ostra - copper and barite, and Crucea-Botuşana - uranium) has resulted in the accumulation of surplus chemicals with direct action on the ecosystem. The aim of this study was to analyze the possible damage on some woody species (Picea abies L., Populus tremulaL., Salix alba L., Betula verrucosa Ehrh.,and Larix decidua Mill.) and their adaptive and phytoremediation capacity thro...

  9. Comparative Analysis of some Vernal Pollen Concentrations in Timisoara (Romania, Szeged (Hungary, Novi Sad (Serbia and Ljubljana (Slovenia

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2009-11-01

    Full Text Available he aim of the study was to compare the airborne concentrations of pollen produced by vernal flowering trees taxa (Alnus, Betula, Carpinus, Corylus, Fraxinus, Platanus, Populus, Quercus, Taxaceae/Cupressaceae in the cities of Timisoara (Romania, Szeged (Hungary, Novi Sad (Serbia and Ljubljana (Slovenia during the years 20062008. Annual variations in the concentration of pollen in the atmosphere were analysed by the volumetric method. In these cities, the period with the greatest diversity of pollen types is spring. These trees are found in mixed forests and are used in urban landscaping and home gardens. Inter-annual differences can be seen in the seasonal behaviour of the pollen in Novi Sad, 2008 being the year in which the highest levels of airborne pollen were reached. During the 3-year period, pollen of the representatives of the family Betulaceae accounted for a significant proportion of total pollen, predominated by Betula pollen and a considerably lower proportion of Alnus, Carpinus and Corylus airpollen. Taxaceae/Cupressaceae pollen appears in the atmospheric pollen spectra of all localities in high concentrations. These pollen grains are the main source of allergens in springtime. Results of the study reveal important differences between the cities.

  10. Cadmium accumulation and its effect on the in vitro growth of woody fleabane and mycorrhized white birch

    International Nuclear Information System (INIS)

    The effect of Cd on woody fleabane (Dittrichia viscosa (L.) Greuter) and white birch (Betula celtiberica Rothm. and Vasc.) was examined. Woody fleabane and white birch were grown in vitro in Murashige, T., Skoog, F., [1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant. 15, 473-479] (MS) plus Cd (10 mg Cd kg-1) and except for root length in white birch, plant development was inhibited when Cd was added. Cd accumulation in above-ground tissues showed differences among clones, reaching 1300 and 463 mg Cd kg-1 dry wt. in selected clones of woody fleabane and white birch, respectively. Tolerance of Paxillus filamentosus (Scop) Fr. to Cd was also examined before mycorrhization. Plants of mycorrhized white birch grown in the presence of Cd had a better development and accumulated more Cd in their shoots than the non-mycorrhized ones. The use of selected clones of woody fleabane and the mycorrhization of white birch enhance extraction efficiency from contaminated soils in phytoremediation programs. - The high accumulation of Cd observed in selected clones of Dittrichia viscosa and mycorrhized Betula celtiberica grown in vitro implies a potential application for phytoextraction

  11. Cadmium accumulation and its effect on the in vitro growth of woody fleabane and mycorrhized white birch

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, R.; Bertrand, A.; Casares, A. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain); Garcia, R. [Departamento de Quimica Fisica y Analitica, Oviedo University, Julian Claveria s/n, 33071 Oviedo (Spain); Gonzalez, A. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain)], E-mail: aidag@uniovi.es; Tames, R.S. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain)

    2008-04-15

    The effect of Cd on woody fleabane (Dittrichia viscosa (L.) Greuter) and white birch (Betula celtiberica Rothm. and Vasc.) was examined. Woody fleabane and white birch were grown in vitro in Murashige, T., Skoog, F., [1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant. 15, 473-479] (MS) plus Cd (10 mg Cd kg{sup -1}) and except for root length in white birch, plant development was inhibited when Cd was added. Cd accumulation in above-ground tissues showed differences among clones, reaching 1300 and 463 mg Cd kg{sup -1} dry wt. in selected clones of woody fleabane and white birch, respectively. Tolerance of Paxillus filamentosus (Scop) Fr. to Cd was also examined before mycorrhization. Plants of mycorrhized white birch grown in the presence of Cd had a better development and accumulated more Cd in their shoots than the non-mycorrhized ones. The use of selected clones of woody fleabane and the mycorrhization of white birch enhance extraction efficiency from contaminated soils in phytoremediation programs. - The high accumulation of Cd observed in selected clones of Dittrichia viscosa and mycorrhized Betula celtiberica grown in vitro implies a potential application for phytoextraction.

  12. Fire drives transcontinental variation in tree birch defense against browsing by snowshoe hares.

    Science.gov (United States)

    Bryant, John P; Clausen, Thomas P; Swihart, Robert K; Landhäusser, Simon M; Stevens, Michael T; Hawkins, Christopher D B; Carrière, Suzanne; Kirilenko, Andrei P; Veitch, Alasdair M; Popko, Richard A; Cleland, David T; Williams, Joseph H; Jakubas, Walter J; Carlson, Michael R; Bodony, Karin Lehmkuhl; Cebrian, Merben; Paragi, Thomas F; Picone, Peter M; Moore, Jeffrey E; Packee, Edmond C; Malone, Thomas

    2009-07-01

    Fire has been the dominant disturbance in boreal America since the Pleistocene, resulting in a spatial mosaic in which the most fire occurs in the continental northwest. Spatial variation in snowshoe hare (Lepus americanus) density reflects the fire mosaic. Because fire initiates secondary forest succession, a fire mosaic creates variation in the abundance of early successional plants that snowshoe hares eat in winter, leading to geographic variation in hare density. We hypothesize that fire is the template for a geographic mosaic of natural selection: where fire is greatest and hares are most abundant, hare browsing has most strongly selected juvenile-phase woody plants for defense. We tested the hypothesis at multiple spatial scales using Alaska birch (Betula neoalaskana) and white birch (Betula papyrifera). We also examined five alternative hypotheses for geographic variation in antibrowsing defense. The fire-hare-defense hypothesis was supported at transcontinental, regional, and local scales; alternative hypotheses were rejected. Our results link transcontinental variation in species interactions to an abiotic environmental driver, fire. Intakes of defense toxins by Alaskan hares exceed those by Wisconsin hares, suggesting that the proposed selection mosaic may coincide with a geographic mosaic of coevolution. PMID:19422319

  13. Effects of Flavonoid-rich Plant Extracts on In vitro Ruminal Methanogenesis, Microbial Populations and Fermentation Characteristics.

    Science.gov (United States)

    Kim, Eun T; Guan, Le Luo; Lee, Shin J; Lee, Sang M; Lee, Sang S; Lee, Il D; Lee, Su K; Lee, Sung S

    2015-04-01

    The objective of this study was to evaluate the in vitro effects of flavonoid-rich plant extracts (PE) on ruminal fermentation characteristics and methane emission by studying their effectiveness for methanogenesis in the rumen. A fistulated Holstein cow was used as a donor of rumen fluid. The PE (Punica granatum, Betula schmidtii, Ginkgo biloba, Camellia japonica, and Cudrania tricuspidata) known to have high concentrations of flavonoid were added to an in vitro fermentation incubated with rumen fluid. Total gas production and microbial growth with all PE was higher than that of the control at 24 h incubation, while the methane emission was significantly lower (pPunica, Betula, Ginkgo, Camellia, and Cudrania treatments, respectively. Ciliate populations were reduced by more than 60% in flavonoid-rich PE treatments. The Fibrobacter succinogenes diversity in all added flavonoid-rich PE was shown to increase, while the Ruminoccocus albus and R. flavefaciens populations in all PE decreased as compared with the control. In particular, the F. succinogenes community with the addition of Birch extract increased to a greater extent than that of others. In conclusion, the results of this study showed that flavonoid-rich PE decreased ruminal methane emission without adversely affecting ruminal fermentation characteristics in vitro in 24 h incubation time, suggesting that the flavonoid-rich PE have potential possibility as bio-active regulator for ruminants. PMID:25656200

  14. AcEST: BP919966 [AcEST

    Lifescience Database Archive (English)

    Full Text Available d B8QJH1 Definition tr|B8QJH1|B8QJH1_BETVE Histidine kinase 2 (Fragment) OS=Betula verrucosa Align length 80...icant alignments: (bits) Value tr|B8QJH1|B8QJH1_BETVE Histidine kinase 2 (Fragment) OS=Betula v... 110 3e-23... (Putative histi... 102 1e-20 tr|Q9C5U0|Q9C5U0_ARATH Histidine kinase OS=Arabidopsis...279 OS=Striga asiatica PE=2 SV=1 102 1e-20 tr|Q76GZ9|Q76GZ9_MAIZE Histidine kinase 3 OS=Zea mays GN=ZmHK3a ...... 101 2e-20 tr|Q75WE8|Q75WE8_MAIZE Histidine kinase 3 OS=Zea mays GN=ZmHK3b ... 101 2e-20 tr|Q5JJP1|Q5JJP1_ORYSJ Putative his

  15. Holocene vegetation and climate change on the Haanja heights, South-East Estonia

    International Nuclear Information System (INIS)

    The development of forests on the Haanja Heights has been controlled by external factors, including climate, soils, hydrology, and human impact. The sediment sequence from Lake Kirikumaee, which covers about 12 000 years, records the vegetation history throughout the Late Glacial and Holocene. In the Alleroed, woodland tundra with sparse birch and willow was established. Grass-shrub tundra in the Younger Dryas was replaced by birch forest in the Pre-Boreal. During the Holocene two major shifts in vegetation dynamics occurred: the first about 8500 BP with a sharp decline in Betula-Pinus forest and development of broad-leaved forest, and the second about 3500 BP, with a decline in broad-leaved forest and regeneration of Pinus-Betula forest with a high share of Picea. The climate modelling, based on pollen record and lake-level changes, suggest cold, severe climate with low precipitation values in the early Pre-Boreal. Between 9500-8500 BP the climate was rather stable. The lake level first rose, then stabilized, and finally dropped. The sharp climate amelioration in the late Boreal together with the humidity increase resulted in a lake-level rise. The decreased precipitation and rather high summer temperatures, increased evapotranspiration, and reduced water balance are characteristic of the Sub-Boreal. Since 3500 BP, the climate deteriorated and mixed coniferous forest started to dominate. Several small climatic fluctuations, including the Little Ice Age cooling, have been traced by modelling. (author)

  16. Pollen calendar of Lublin, 1995-2000

    Directory of Open Access Journals (Sweden)

    Krystyna Piotrowska

    2012-12-01

    Full Text Available The measurements of pollen fall were carried out in Lublin in 1995 - 2000 years by the gravimetric method. The modified Durham sampler was applied, located at 9 m above ground level. On the base of results 6 year observations - the pollen calendar for Lublin was prepared. The following 15 plant taxa were taken under consideration: Alnus, Corylus, Cupressaceae, Populus, Fraxinus, Betula, Quercus, Pinaceae, Poaceae, Rumex, Plantago, Urtica, Chenopodiaceae, Artemisia and Ambrosia. The anemophilous plants' pollen season in Lublin began in half of February and lasted till half of September. First appeared pollen grains of decidous tress' and shrubs, then the coniferous. High values of pollen fall of these plants were noted till the end of May. Start of grass pollen season was recorded from the half of May, and at the latter part of this month, also other herbaceous plants. The highest concentrations of pollen were found in April and May when trees and shrubs pollinated. The highest annual totals were marked for plants of the following taxa: Betula, Poaceae, Pinaceae, Alnus, Urtica.

  17. Vegetation and climate in the Western Sayan Mts according to pollen data from Lugovoe Mire as a background for prehistoric cultural change in southern Middle Siberia

    Science.gov (United States)

    Blyakharchuk, Tatiana A.; Chernova, Natalia A.

    2013-09-01

    On the basis of pollen and spore analyses and radiocarbon dating of peat deposits of Lugovoe Mire in southern Middle Siberia, changes of vegetation and climate of the Western Sayan Mts and the Khakasia Republic (Russia) since 6000 yr 14C BP (5000 cal yr BC) are found to correspond with the development of archaeological cultures and with the pollen-based palaeoclimatic reconstruction of Levina and Orlova (1993) constructed for the forest-steppe zone of the south of West Siberia. Three phases in the development of the regional vegetation (Abies, Betula, and Pinus) are distinguished in the pollen diagram of Lugovoe Mire, which form the environmental background for the archaeological cultures developed in this region. The first penetration of ancient hunting-fishing tribes into this area occurred during the ‘Abies stage' of the vegetation. Bronze Age cultures practiced agriculture and animal husbandry mostly during the ‘Betula stage'. Beginning in the Iron Age, archaeological cultures bloomed in the study area on the background of expanding Pinus sylvestris forests. The origin of all these cultures was connected with migrations of people from the southwest or southeast. An important reason for these migrations was dry climatic phases at millennial intervals, which influenced especially strongly the more southerly homelands of the migrating ancient tribes.

  18. Late glacial and holocene landscapes of central Beringia

    Science.gov (United States)

    Lozhkin, Anatoly V.; Anderson, Patricia; Eisner, Wendy R.; Solomatkina, Tatiana B.

    2011-11-01

    New palynological and sedimentological data from St. Lawrence Island present a rare view into late-glacial and Holocene environments of the central Bering Land Bridge. The late glaciation was a time of dynamic landscape changes in south-central Beringia, with active thermokarst processes, including the formation and drainage of thaw lakes. The presence of such a wet, unstable substrate, if widespread, probably would have had an adverse impact on food sources and mobility for many of the large mammal populations. The establishment of Betula shrub tundra on the island suggests late-glacial summers that were warmer than present, consistent with regional paleoclimatic interpretations. However, the increasing proximity to the Bering Sea, as postglacial sea levels rose, modified the intensity of warming and prevented the establishment of deciduous forest as found in other areas of Beringia at this time. The mid- to late Holocene is marked by more stable land surfaces and development of Sphagnum and Cyperaceae peat deposits. The accumulation of organic deposits, decline of shrub Betula, and decrease in thermokarst disturbance suggest that conditions were cooler than the previous. A recent decline in peat accumulation at the study sites may relate to local geomorphology, but similar decreases have been noted for other arctic regions.

  19. Adaptation of Forest Management Regimes in Southern Sweden to Increased Risks Associated with Climate Change

    Directory of Open Access Journals (Sweden)

    Narayanan Subramanian

    2015-12-01

    Full Text Available Even though the growth rates of most tree species in Sweden is expected to increase in the near future as a result of climate change, increased risks of damage by storms and various pests and pathogens, notably root rot and bark beetles, may also occur. Thus, forest management practices such as changes to thinning regimes, reductions in rotation lengths, and switching to other species (native or exotic may represent adaptive management strategies to increase the resistance and resilience of Swedish forests to climate change. Clearly, thorough analyses examining the effects of anticipated climatic changes on damage levels, and the potentially relieving effects of possible management adaptations are needed before implementing such changes. In this study, damage caused by storms, root rot and bark beetles (single and in various combinations under selected climate and management scenarios were simulated in Norway spruce (Pice abies L. Karst stands. The results indicate that reductions in thinning intensity and rotation lengths could improve both volume production and profitability in southern Sweden. In addition, cultivation of rapidly growing species, such as hybrid larch (Larix × marschlinsii Coaz. and hybrid aspen (Populus tremula L. × P. tremuloides Michx., could be as profitable as Norway spruce cultivation, or even more profitable. However, slow-growing species, such as Silver birch (Betula pendula Roth, Downy birch (Betula pubescens Ehrh. and European beech (Fagus sylvatica L. indicated low economic output in terms of Land Expectation Value.

  20. Increasing shrub abundance and N addition in Arctic tundra affect leaf and root litter decomposition differently

    Science.gov (United States)

    McLaren, J.; van de Weg, M. J.; Shaver, G. R.; Gough, L.

    2013-12-01

    Changes in global climate have resulted in a ';greening' of the Arctic as the abundance of deciduous shrub species increases. Consequently, not only the living plant community, but also the litter composition changes, which in turn can affect carbon turnover patterns in the Arctic. We examined effects of changing litter composition (both root and leaf litter) on decomposition rates with a litter bag study, and specifically focused on the impact of deciduous shrub Betula nana litter on litter decomposition from two evergreen shrubs (Ledum palustre, and Vaccinium vitis-idaea) and one graminoid (Eriophorum vaginatum) species. Additionally, we investigated how decomposition was affected by nutrient availability by placing the litterbags in an ambient and a fertilized moist acidic tundra environment. Measurements were carried out seasonally over 2 years (after snow melt, mid-growing season, end growing season). We measured litter mass loss over time, as well as the respiration rates (standardized for temperature and moisture) and temperature sensitivity of litter respiration at the time of harvesting the litter bags. For leaves, Betula litter decomposed faster than the other three species, with Eriophorum leaves decomposing the slowest. This pattern was observed for both mass loss and litter respiration rates, although the differences in respiration became smaller over time. Surprisingly, combining Betula with any other species resulted in slower overall weight loss rates than would be predicted based on monoculture weight loss rates. This contrasted with litter respiration at the time of sampling, which showed a positive mixing effect of adding Betula leaf liter to the other species. Apparently, during the first winter months (September - May) Betula litter decomposition is negatively affected by mixing the species and this legacy can still be observed in the total mass loss results later in the year. For root litter there were fewer effects of species identity on root

  1. ОЦЕНКА ОТНОСИТЕЛЬНОГО ЖИЗНЕННОГО СОСТОЯНИЯ НАСАЖДЕНИЙ БЕРЕЗЫ ПОВИСЛОЙ (BETULA PENDULA ROTH.) И ТОПОЛЯ БАЛЬЗАМИЧЕСКОГО (POPULUS BALSAMIFERA L.) В ПРОМЫШЛЕННОЙ И СЕЛИТЕБНОЙ ЗОНЕ СТЕРЛИТАМАКСКОГО ПРОМЫШЛЕННОГО ЦЕНТРА

    OpenAIRE

    ИБРАГИМОВА А.Х.; ТАГИРОВА О.В.; ГИНИЯТУЛЛИН Р.Х.; КУЛАГИН А.Ю.

    2014-01-01

    Определение относительного жизненного состояния древесных насаждений позволяет оценить устойчивость отдельных деревьев и насаждений к воздействию техногенных факторов среды. Исследованы насаждения березы повислой и тополя бальзамического в промышленной и селитебной зоне Стерлитамакского промышленного центра. При сборе и обработке фактического материала использованы общепринятые методы изучения лесных насаждений.Произведены инструментальные (диаметр, высота, возраст) и визуальные определения (...

  2. Study on Soil Fertility of Different Forest Types in Jialing River Source%嘉陵江源头几种林地土壤肥力状况调查

    Institute of Scientific and Technical Information of China (English)

    谭胡燕; 刘瑞英; 杨改河; 任学敏; 王得祥

    2011-01-01

    Based on analysis of soil pH, the content of organic matter and main nutrient at the different levels of soil under seven different forest types (Quercus aliena BI. Var. Acuteserrate, Betula albo-sinensis, Pinus tabulaeformis , Pinus armandii , Abies fargesii , coniferous and broad-leaved mixed forest, shrub forest)in Jialing river of source, this paper studied on soil fertility of different forest types. The result showed that the soil in Pinus armandii, Pinus tabulae formis and coniferous and broad-leaved mixed forest were near neutral, the soil in Quercus aliena BI. Var. Acuteserrate, Betula albo-sinensis and shrub forest were slightly acidic, the soil in Abies fargesii was acidic. The soil pH, the contents of soil organic matter, total N and P, alkali-hydro N and available P tended to decrease with soil depth. The soil fertility was increased in the order of Pinus armandii <Lpinus tabulae formis <coniferous and broad-leaved mixed ioresKQuercus aliena BI. Var. Acuteserrate<shrub forest<Abies fargesii<L Betula albo-sinensis.%以嘉陵江源头风景区7种林型(锐齿栎林、红桦林、油松林、华山松林、巴山冷杉林、针阔混交林及灌木林)土壤为研究对象,通过对林地土壤不同层次pH、有机质及主要养分含量的测定,分析不同林型下土壤肥力的差异状况.结果表明,华山松林、油松林和针阔混交林的土壤趋于中性,锐齿栎林、红桦林、灌木林的土壤趋于弱酸性,而巴山冷杉林的土壤呈酸性.随土壤深度增加,土壤pH升高,土壤有机质、全氮、全磷、碱解氮、有效磷含量均呈下降趋势.土壤综合肥力优劣为华山松林<油松林<针阔混交林<锐齿栎林<灌木林<巴山冷杉林<红桦林.

  3. Vegetation Dynamics in the Kenai Lowlands, Alaska during the Late Pleistocene and Holocene

    Science.gov (United States)

    Jones, M. C.; Peteet, D. M.

    2005-12-01

    The use of paleoinformation through ecosystem reconstruction can help us understand the behavior and sensitivity of the boreal forest as climate continues to change. A 2.5-meter sediment core extracted from Swanson Fen, a muskeg in the northern Kenai Lowlands on the Kenai Peninsula, Alaska, provides a sensitive Holocene paleoenvironmental record that lies in an ecotone between interior boreal forest and maritime coastal forest today. The core was sampled at 2-cm intervals and processed for pollen and spores. Five intervals were dated using AMS radiocarbon dating, and the basal macrofossils produced an age of 12,245 ±45 radiocarbon years. The central Kenai Peninsula Lowlands underwent a number of marked vegetational and climatic changes since deglaciation. Four distinct vegetation zones reveal changes starting in the late Pleistocene. The pioneer vegetation includes a dominance of herbaceous ( Artemisia, Apiaceae, Asteroideae)and shrubby ( Betula) species. The second zone (beginning at 9890±45 radiocarbon years) and marking the Holocene boundary, shows a striking increase in Polypodiaceae (ferns) and Picea (spruce) and a decrease in shrubby species such as Betula, indicative of warming. The third zone indicates a decline in Polypodiaceae and a reemergence of Betula species, while the final most recent zone reveals a rapid resurgence in Picea and Tsuga mertensiana (Mountain hemlock) species. While a general warming trend occurred following deglaciation, vegetation patterns suggest extended periods of increased precipitation, for example in the early Holocene, as is evidenced by the plethora of Polypodiaceae. A movement and an intensification of the Aleutian Low could explain these periods of increased precipitation over the Kenai Peninsula. Alternatively, this spike in Polypodiaceae can be explained by increased disturbance. The presence of 10 % Picea pollen at the base of the core suggests that one of the Picea species may have survived the last glaciation in the

  4. Uptake of americium-241 by plants from contaminated Chernobyl exclusive zone test site soils

    International Nuclear Information System (INIS)

    Americium-241 was found to accumulate in soils and biological objects of the environment. Its concentration has increased many times after the Chernobyl disaster and can be expected to increase about 40 times in the future. This research concentrated on the contaminated exclusive Chernobyl zone polluted by trace radionuclides, their behavior and accumulation by various plant species. Special attention is devoted to the bioavailability of 241Am to the plants Galium rivale, G. tinctorium, G. aparine, G. intermedium, Berteroa incana, Artemisia absinthium, A. vulgaris, Centaurea borysthenica, C. arenaria, Cirsium arvense, Succissa pratensis, Solidago virgaurea, Linaria vulgaris, Lepidium ruderale, Stenactis annua, Veronica maxima, Verbascum lychnitis, Euphorbia cyparissias, Genista tinctoria, Erigeron canadensis, Oenothera biennis, Betula pendula and Quercus robur, which were collected from the Chernobyl, Kopachi, and Yanov districts. The plant samples of Oenothera biennis, Betula pendula and Quercus robur were collected from the Yanov district, where the soil contamination by 241Am and 137Cs was at the level of 660 and 27 MBq/m2, respectively. Gamma spectroscopy and radiochemical methods were used to estimate the activity concentration of 137Cs, 90Sr, 238Pu, 239+240Pu, 241Am. The radionuclides were measured in the dry green mass of the plant samples and in the dry soils. The contamination of the Oenothera biennis, Betula pendula and Quercus robur samples by 137Cs was (5.8±1,5)x106, (7.4±1.1)x105, and (2.6±0.2)x106 Bq/kg dry mass, respectively, and contamination by 241Am was 47±5, 45±3 and 3.2±0.2 Bq/kg, respectively. The soil-to-plant transfer ratio for 137Cs ranged lay within the interval of 0.2 to 0.03 Bq/kg : Bq/m2, the the transfer ratio for 241Am did not exceed 7x10-5 Bq/kg : Bq/m2. The coefficient of the relative contents of the 241Am/239+240Pu radionuclides in the various plant samples varied from 3.2 to 8.3, while for soil from the Yanov district this

  5. A new Middle Pleistocene interglacial record from Denmark: Chronostratigraphic correlation, palaeovegetation and fire dynamics

    DEFF Research Database (Denmark)

    Kuneš, Petr; Kjærsgaard Sørensen, Malene; Buylaert, Jan-Pieter; Murray, Andrew S.; Houmark‐Nielsen, Michael; Odgaard, Bent Vad

    2013-01-01

    Germany. Numerical analyses (REVEALS and DCA) indicate that forests during the temperate stage were dense and that vegetation openness increased only towards the end of the interglacial, accompanied by increased fire occurrence. A short interstadial sequence with a dominance of Pinus and Betula and the...... Trelde Klint, Denmark, and analyse its biostratigraphy, correlation with other European records, vegetation development, fire dynamics and absolute dating. Except for a slight truncation of the early part of the record, the pollen stratigraphy exhibits a full interglacial succession, including temperate...... presence of Larix is present above the interglacial deposit. We argue that lack of attention to differences in fire regimes may hamper understanding of between-site correlations of interglacial pollen records. OSL dating, using a novel feldspar technique, yields an average age of 350±20 ka for the sandy...

  6. Determination of de novo and pool emissions of terpenes from four common boreal/alpine trees by 13CO2 labelling and PTR-MS analysis.

    Science.gov (United States)

    Ghirardo, Andrea; Koch, Kristine; Taipale, Risto; Zimmer, Ina; Schnitzler, Jörg-Peter; Rinne, Janne

    2010-05-01

    Boreal forests emit a large amount of monoterpenes into the atmosphere. Traditionally these emissions are assumed to originate as evaporation from large storage pools. Thus, their diurnal cycle would depend mostly on temperature. However, there is indication that a significant part of the monoterpene emission would originate directly from de novo synthesis. By applying 13CO2 fumigation and analyzing the isotope fractions with proton transfer reaction mass spectrometry (PTR-MS) and classical GC-MS, we determined the fractions of monoterpene emissions originating from de novo biosynthesis in Pinus sylvestris (58%), Picea abies (33.5%), Larix decidua (9.8%) and Betula pendula (100%). Application of the observed split between de novo and pool emissions from P. sylvestris in a hybrid emission algorithm resulted in a better description of ecosystem scale monoterpene emissions from a boreal Scots pine forest stand. PMID:20040067

  7. Aeropalynologic analysis of Timisoara (Romania during 2006 year

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2007-05-01

    Full Text Available This article presents the results of a one year qualitative-quantitative study of airborne pollen. The objective of the investigation was to analyse the daily presence and distribution of pollen and to identify the pollen types that are abundantly represented in the atmosphere of the city of Timisoara. A continuous aeropalynologic survey was accomplished between 1 mai 2006 and 8 octombrie 2006. Plants with anemophilous pollination were the best represented: Pinaceae, Poaceae, Plantago, Rumex, Urtica, Chenopodiaceae/Amaranthaceae, Artemisia, Ambrosia, Fraxinus, Salix, Betula, Carpinus, Quercus, Juglans, Platanus, Morus, Tilia. The total pollen spectrum was represented by 17 pollen types. Ambrosia artemisiifolia pollen types was dominant. The highest level of pollen emission was recorded during August-September.

  8. AcEST: DK954251 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ia with plantlets Developmental stage gametophytes with sporophytes...... 37 0.038 sp|Q42377|EC2_ARATH EC protein homolog 2 OS=Arabidopsis thaliana... 37 0.049 sp|Q40396|MT2_NICGU Metalloth...ct: 30 GAEMGVGAENGCKCGANCQCDPCTC 54 >tr|Q508T1|Q508T1_9ROSI Metallothionein-like protein OS=Betula platyphylla PE=4 SV=1 Length...56 Definition Adiantum capillus-veneris mRNA. clone: TST39A01NGRL0019_P05. 5' end sequence. Accession DK954251 Tissue type prothall...p|P25860|MT2A_ARATH Metallothionein-like protein 2A OS=Arabidop... 39 0.013 sp|P43396|MT1_COFAR Metallothionein-like prote

  9. AcEST: DK962973 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ia with plantlets Developmental stage gametophytes with sporophytes...032 sp|Q42377|EC2_ARATH EC protein homolog 2 OS=Arabidopsis thaliana... 37 0.042 sp|Q40396|MT2_NICGU Metallothionein-like prote...MGVGAENGCKCGANCQCDPCTC 54 >tr|Q508T1|Q508T1_9ROSI Metallothionein-like protein OS=Betula platyphylla PE=4 SV=1 Length...47 Definition Adiantum capillus-veneris mRNA. clone: TST39A01NGRL0015_E16. 5' end sequence. Accession DK962973 Tissue type prothall...ionein-like protein 2A OS=Arabidop... 39 0.011 sp|P43396|MT1_COFAR Metallothionein-like prote

  10. Characterisation of Holocene plant macrofossils from North Spanish ombrotrophic mires: vascular plants

    Directory of Open Access Journals (Sweden)

    M. Souto

    2016-06-01

    Full Text Available Methods and criteria that were used to identify plant macrofossils from four ombrotrophic mires in northern Spain are presented. Twelve monocotyledon and ten dicotyledon species were recorded. Some were identified from vegetative or reproductive macroremains (Eriophorum angustifolium, Molinia caerulea, Calluna vulgaris, Erica mackaiana, Erica tetralix, Potentilla erecta, while others were recognised only by their fruits (Rhynchospora alba, Carex durieui, Carex echinata, Carex binervis, Carex demissa, Betula alba, seeds (Juncus squarrosus, Juncus bulbosus, Luzula multiflora, Narthecium ossifragum, Drosera rotundifolia, Drosera intermedia, Caltha palustris, Daboecia cantabrica, rhizome fragments with remains of leaves (Agrostis curtisii, or twigs with buds and leaves (Vaccinium myrtillus. Descriptions of the specific distinctive characters for the plant macrofossils that were recorded are accompanied by illustrations that facilitate their interpretation. Dichotomous identification keys are also provided.

  11. Stimulated production of steroids in Inonotus obliquus by host factors from birch.

    Science.gov (United States)

    Wang, Lian-Xia; Lu, Zhen-Ming; Geng, Yan; Zhang, Xiao-Mei; Xu, Guo-Hua; Shi, Jin-Song; Xu, Zheng-Hong

    2014-12-01

    Steroids was considered as one of the bioactive components in Inonotus obliquus, while this kind of secondary metabolites are less accumulated in cultured mycelia. In this study, effect of extracts from bark and core of host-related species, birch (Betula platyphylla Suk.), on steroid production of I. obliquus in submerged culture were evaluated. The results showed that all dosages (0.01 and 0.1 g/L) of aqueous extracts and methanol extracts from birch bark and birch core possessed significantly stimulatory effect on steroid production of I. obliquus (P obliquus simultaneously increased in the presence of aqueous extract and methanol extract from birch bark. The results presented herein indicate that extracts from birch bark could act as an inducer for steroid biosynthesis of I. obliquus. PMID:25027706

  12. Значение бонитета условий местопроизрастания березы в экологии Inonotus obliquus (Pers. ) Pil

    OpenAIRE

    Баландайкин, Михаил

    2012-01-01

    Устанавливается специфика влияние классов бонитета Betula pendula Roth. на степень встречаемости в формируемых ею насаждениях патологического агента Inonotus obliquus (Pers.) Pil.

  13. ВЛИЯНИЕ ВЕРТИКАЛЬНОЙ СТРУКТУРЫ БЕРЕЗОВЫХ НАСАЖДЕНИЙ НА РАСПРОСТРАНЕННОСТЬ INONOTUS OBLIQUUS (PERS.) PIL

    OpenAIRE

    Баландайкин, М.

    2013-01-01

    В настоящей работе речь идет о нативной согласованности дисперсии Inonotus obliquus (Pers.) Pil. и формы древостоя Betula pendula Roth. Также рассматриваются некоторые соподчиненные закономерности.

  14. Properties of Modified Phenol-Formaldehyde Adhesive for Plywood Panels Manufactured from High Moisture Content Veneer

    Directory of Open Access Journals (Sweden)

    Pavlo Bekhta

    2015-01-01

    Full Text Available This paper presents the results of laboratory investigations of bonding high moisture content (15 % birch veneers (Betula pubescens Ehrh. with the use of modifi ed phenol-formaldehyde (PF resin. Wheat starch, rye flour, resorcinol and phenol-resorcinol-formaldehyde resin were chosen as modifying agents. Dynamic viscosity, hydrogen ions concentration, solid content, curing time, pot life of developed adhesive compositions and shear strength of plywood samples were evaluated. ANOVA analysis has shown that type, mixture and content of modifying agents affect significantly the mechanical performance of plywood panels. The obtained results of shear strength values were above the standard requirements (1 N/mm2, and the properties of samples met the European standard EN 314-2 for gluing quality of class 3 and such plywood panels can be used in exterior conditions.

  15. METHODS OF BIOMONITORING IN URBAN ENVIRONMENT: ALLERGENIC POLLEN IN WESTERN ROMANIA AND RELATIONSHIPS WITH METEOROLOGICAL VARIABLES

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2015-12-01

    Full Text Available Biomonitoring results showed that a total of 23 pollen types were located in the air of the study area. The analysis of the airborne pollen content concerned 20 taxa, whose pollen has allergenic properties and occurs in large quantities in the air of Timisoara: Alnus, Taxaceae/Cupressaceae, Salix, Populus, Ulmus, Fraxinus, Juglans, Quercus, Tilia, Pinaceae, Corylus, Carpinus, Betula, Poaceae, Rumex, Plantago, Urticaceae, Chenopodiaceae/Amaranthaceae, Ambrosia and Artemisia. Analysis of the pollen count in Timisoara was performed on the basis of the data collected in the year 2009. Ambrosia artemisiifolia, Urticaceae and Poaceae reached the highest atmospheric pollen concentrations in Timisoara. Multiple regression analysis was found to be a very valuable tool for identifying the weather variables most closely associated with atmospheric pollen seasons.

  16. Epitope grafting, re-creating a conformational Bet v 1 antibody epitope on the surface of the homologous apple allergen Mal d 1

    DEFF Research Database (Denmark)

    Holm, Jens; Ferreras, Mercedes; Ipsen, Henrik; Würtzen, Peter A; Gajhede, Michael; Larsen, Jørgen N; Lund, Kaare; Spangfort, Michael D

    2011-01-01

    Birch-allergic patients often experience oral allergy syndrome upon ingestion of vegetables and fruits, most prominently apple, that is caused by antibody cross-reactivity of the IgE antibodies in patients to proteins sharing molecular surface structures with the major birch pollen group 1 allergen...... from Betula verrucosa (Bet v 1). Still, to what extent two molecular surfaces need to be similar for clinically relevant antibody cross-reactivity to occur is unknown. Here, we describe the grafting of a defined conformational antibody epitope from Bet v 1 onto the surface of the homologous apple...... allergen Malus domestica group 1 (Mal d 1). Engineering of the epitope was accomplished by genetic engineering substituting amino acid residues in Mal d 1 differing between Bet v 1 and Mal d 1 within the epitope defined by the mAb BV16. The kinetic parameters characterizing the antibody binding interaction...

  17. Which plant for which skin disease? Part 2: Dermatophytes, chronic venous insufficiency, photoprotection, actinic keratoses, vitiligo, hair loss, cosmetic indications.

    Science.gov (United States)

    Reuter, Juliane; Wölfle, Ute; Korting, Hans Christian; Schempp, Christoph

    2010-11-01

    This paper continues our review of scientifically evaluated plant extracts in dermatology. After plants effective against dermatophytes, botanicals with anti-edema effects in chronic venous insufficiency are discussed. There is good evidence from randomized clinical studies that plant extracts from grape vine leaves (Vitis vinifera), horse chestnut (Aesculus hippocastanum), sea pine (Pinus maritima) and butcher's broom (Ruscus aculeatus) can reduce edema in chronic venous insufficiency. Plant extracts from witch hazel (Hamamelis virginiana), green tea (Camellia sinensis), the fern Polypodium leucotomos and others contain antioxidant polyphenolic compounds that may protect the skin from sunburn and photoaging when administered topically or systemically. Extracts from the garden spurge (Euphorbia peplus) and from birch bark (Betula alba) have been shown to be effective in the treatment of actinic keratoses in phase II studies. Some plant extracts have also been investigated in the treatment of vitiligo, various forms of hair loss and pigmentation disorders, and in aesthetic dermatology. PMID:20707877

  18. Quantification of C uptake in subarctic birch forest after setback by an extreme insect outbreak

    DEFF Research Database (Denmark)

    Heliasz, Michal; Johansson, Torbjörn; Lindroth, Anders;

    2011-01-01

    ) forests in northern Scandinavia cyclically every 9–10 years and occasionally (50–150 years) extreme population densities can threaten ecosystem stability. Here we report impacts on C balance following a 2004 outbreak where a widespread area of Lake Torneträsk catchment was severely defoliated. We show......The carbon dynamics of northern natural ecosystems contribute significantly to the global carbon balance. Periodic disturbances to these dynamics include insect herbivory. Larvae of autumn and winter moths (Epirrita autumnata and Operophtera brumata) defoliate mountain birch (Betula pubescens...... that in the growing season of 2004 the forest was a much smaller net sink of C than in a reference year, most likely due to lower gross photosynthesis. Ecosystem respiration in 2004 was smaller and less sensitive to air temperature at nighttime relative to 2006. The difference in growing season uptake...

  19. Holocene stratigraphy and vegetation history in the Scoresby Sund area, East Greenland

    DEFF Research Database (Denmark)

    Funder, Svend Visby

    1978-01-01

    The Holocene stratigraphy in Scoresby Sund is based on climatic change as reflected by fluctuations in fjord and valley glaciers, immigration and extinction of marine molluscs, and the vegetation history recorded in pollen diagrams from five lakes. The histories are dated by C-14, and indirectly by...... thermophilous elements indicating temperatures similar to the present. From 9400 yr BP the fjord glaciers retreated rapidly in the narrow fjords, the few moraines formed are referred to the Rødefjord stages and indicate topographically conditioned stillstands. At 8000 yr BP the low arctic Betula nana imigrated...... into the area, and in the period until 5000 yr BP dense dwarf shrub heath grew in areaS where it is now absent. In the fjords the subarctic Mytilus edulis and Pecten islandica lived, suggesting a climate warmer than the present. From c. 5000 yr BP the dense dwarf shrub heath began to disappear in the...

  20. Managing invasive populations of Asian longhorned beetle and citrus longhorned beetle: a worldwide perspective.

    Science.gov (United States)

    Haack, Robert A; Hérard, Franck; Sun, Jianghua; Turgeon, Jean J

    2010-01-01

    The Asian longhorned beetle (ALB), Anoplophora glabripennis (Motschulsky), and citrus longhorned beetle (CLB), Anoplophora chinensis (Forster) (Coleoptera: Cerambycidae), are polyphagous xylophages native to Asia and are capable of killing healthy trees. ALB outbreaks began in China in the 1980s, following major reforestation programs that used ALB-susceptible tree species. No regional CLB outbreaks have been reported in Asia. ALB was first intercepted in international trade in 1992, mostly in wood packaging material; CLB was first intercepted in 1980, mostly in live plants. ALB is now established in North America, and both species are established in Europe. After each infestation was discovered, quarantines and eradication programs were initiated to protect high-risk tree genera such as Acer, Aesculus, Betula, Populus, Salix, and Ulmus. We discuss taxonomy, diagnostics, native range, bionomics, damage, host plants, pest status in their native range, invasion history and management, recent research, and international efforts to prevent new introductions. PMID:19743916

  1. Interspecific differences in foliar 1 PAHs load between Scots pine, birch, and wild rosemary from three polish peat bogs.

    Science.gov (United States)

    Mętrak, Monika; Aneta, Ekonomiuk; Wiłkomirski, Bogusław; Staszewski, Tomasz; Suska-Malawska, Małgorzata

    2016-08-01

    Pine needles are one of the most commonly used bioindicators of polycyclic aromatic hydrocarbons (PAHs) in the environment. Therefore, the main objective of the current research was the assessment of PAHs accumulation potential of Scots pine (Pinus sylvestris L.) needles in comparison to wild rosemary (Rhododendron tomentosum Harmaja) and birch (Betula spp.) leaves. Our study was carried out on three peat bogs subjected to different degree of anthropopression, which gave us also the opportunity to identify local emission sources. Pine needles had the lowest accumulation potential from all the studied species. The highest accumulation potential, and hence carcinogenic potential, was observed for wild rosemary leaves. As far as emission sources are concerned, the most pronounced influence on atmospheric PAHs loads had traditional charcoal production, resulting in great influx of heavy PAHs. Observed seasonal changes in PAHs concentrations followed the pattern of winter increase, caused mainly by heating season, and summer decrease, caused mainly by volatilization of light PAHs. PMID:27393196

  2. Habitat Ecology of Himalayan Musk Deer (Moschus chrysogaster in Manaslu Conservation Area, Nepal

    Directory of Open Access Journals (Sweden)

    Xiuxiang Meng

    2012-01-01

    Full Text Available The Himalayan musk deer (Moschus chrysogaster is an endangered species found in the Himalayan region of Nepal. This research was conducted in the Manaslu Conservation Area to explore the deers general population status, distribution, habitat preference and conservation threats. Musk deer are distributed within the altitudinal range of 3128-4039 m spanning 35.43 km2, with the most potential habitat in the Prok VDC (Village Development Committee. Within this area the Musk deer highly preferred altitudes between 3601-3800 m, with a 21-30 slope, 26-50% crown cover and 26-50% ground cover. There are significant differences in the use of different habitat types in terms of altitude, slope, crown cover, ground cover and topography. The preferred tree species were Abies spectabilis, Betula utilis and Rhododendron species. Poaching of deer for their musk is the major conservation threat.

  3. Breeding increases the efficacy of Chondrostereum purpureum in the sprout control of birch.

    Directory of Open Access Journals (Sweden)

    Leena Hamberg

    Full Text Available We tested whether the pairing of selected isolates could be used to increase the efficiency of a decay fungus Chondrostereum purpureum (Pers. Ex Fr. Pouzar to control hardwood sprouting in Finland. We paired C. purpureum strains efficient in sprout control or highly active in laccase production, and tested the efficacy of their progeny in spout control experiments. This procedure resulted in a strain with an efficacy superior to that of the parental strains. The mortality of birch (Betula pendula Roth. and B. pubescens Ehrh. 1 cm in stump diameter was 78%, 56% and 9% for the best progeny, the best parental strain and the control, respectively. Mortality was only slightly higher for B. pendula than for B. pubescens but no significant differences were found between the number or maximum height of stump sprouts. Our results showed that cross breeding of this decay fungus is a good alternative in attempts to produce efficient biocontrol agents against hardwood sprouting.

  4. Determination of total Betta-activity and heavy metals in biomonitor species (phytomonitors) from the area of ITR-Sofia

    International Nuclear Information System (INIS)

    For the purposes of environmental assessment of the area around the Research reactor in Sofia, species from monitored control points, selected in a certain way (habitat, population, air and hydrogeological parameters) are examined. Samples from following phytomonitored species: Betula pendula (silver birch) popullus canadensis (Canadian populus), Quercus sp. (Oak), Dactilus glomerata (Cock's-foot), Abies alba (Silver Fir) and Sequoia sempervirens (Coast Redwood) were analyzed. The total beta activity was determined by radiometric analysis and heavy metals content was measured using X-ray fluorescence analysis. The results are discussed in terms of radiation monitoring program of INRNE (gamma-background, aerosols, surface and groundwater, soil, plants) and obtained values are compared with reference points in the country

  5. Two new species of Oobius Trjapitzin (Hymenoptera, Encyrtidae) egg parasitoids of Agrilus spp. (Coleoptera, Buprestidae) from the USA, including a key and taxonomic notes on other congeneric Nearctic taxa

    Science.gov (United States)

    Triapitsyn, Serguei V.; Petrice, Toby R.; Gates, Michael W.; Bauer, Leah S.

    2015-01-01

    Abstract Oobius Trjapitzin (Hymenoptera, Encyrtidae) species are egg parasitoids that are important for the biological control of some Buprestidae and Cerambycidae (Coleoptera). Two species, Oobius agrili Zhang & Huang and Oobius longoi (Siscaro), were introduced into North America for classical biocontrol and have successfully established. Two new native North American species that parasitize eggs of Agrilus spp. (Buprestidae) are described and illustrated from the USA: Oobius minusculus Triapitsyn & Petrice, sp. n. (Michigan), an egg parasitoid of both Agrilus subcinctus Gory on ash (Fraxinus spp.) and Agrilus egenus Gory on black locust (Robinia pseudoacacia L.) trees, and Oobius whiteorum Triapitsyn, sp. n. (Pennsylvania), an egg parasitoid of Agrilus anxius Gory on European white birch (Betula pendula Roth). A taxonomic key and notes on the Nearctic native and introduced Oobius species are also included. PMID:25931963

  6. Two new species of Oobius Trjapitzin (Hymenoptera, Encyrtidae egg parasitoids of Agrilus spp. (Coleoptera, Buprestidae from the USA, including a key and taxonomic notes on other congeneric Nearctic taxa

    Directory of Open Access Journals (Sweden)

    Serguei V. Triapitsyn

    2015-04-01

    Full Text Available Oobius Trjapitzin (Hymenoptera, Encyrtidae species are egg parasitoids that are important for the biological control of some Buprestidae and Cerambycidae (Coleoptera. Two species, O. agrili Zhang & Huang and O. longoi (Siscaro, were introduced into North America for classical biocontrol and have successfully established. Two new native North American species that parasitize eggs of Agrilus spp. (Buprestidae are described and illustrated from the USA: O. minusculus Triapitsyn & Petrice, sp. n. (Michigan, an egg parasitoid of both A. subcinctus Gory on ash (Fraxinus spp. and A. egenus Gory on black locust (Robinia pseudoacacia L. trees, and O. whiteorum Triapitsyn, sp. n. (Pennsylvania, an egg parasitoid of A. anxius Gory on European white birch (Betula pendula Roth. A taxonomic key and notes on the Nearctic native and introduced Oobius species are also included.

  7. A precise study on effects that trigger alkaline hemicellulose extraction efficiency.

    Science.gov (United States)

    Hutterer, Christian; Schild, Gabriele; Potthast, Antje

    2016-08-01

    The conversion of paper-grade pulps into dissolving pulps requires efficient strategies and process steps to remove low-molecular noncellulosic macromolecules generally known as hemicelluloses. Current strategies include alkaline extractions and enzymatic treatments. This study focused on the evaluation of extraction efficiencies in alkaline extractions of three economically interesting hardwood species: beech (Fagus sylvatica), birch (Betula papyrifera), and eucalyptus (Eucalyptus globulus). Substrate pulps were subjected to alkaline treatments at different temperatures and alkalinities using white liquor as the alkali source, followed by analyses of both pulps and hemicellulose-containing extraction lyes. The extracted hardwood xylans have strong potential as an ingredient in the food and pharmaceutical industries. Subsequent analyses revealed strong dependencies of the extraction efficiencies and molar mass distributions of hemicelluloses on the process variables of temperature and effective alkalinity. The hemicellulose content of the initial pulps, the hardwood species, and the type of applied base played minor roles. PMID:27163434

  8. Impact of Wetting/Oven-Drying Cycles on the Mechanical and Physical Properties of Birch Plywood

    Science.gov (United States)

    Sooru, M.; Kasepuu, K.; Kask, R.; Lille, H.

    2015-11-01

    The objective of this study was to explore some physical and mechanical properties and the dimensional stability of birch (Betula sp.) nine-ply veneers glued with phenol-formaldehyde (PF) after 10 cycles of soaking/oven-drying. The properties to be determined were bending strength (BS), modulus of elasticity in bending (MOE), Janka hardness (JH) and thickness swelling (TS), which were tested according to the European Standards (EN). An analytical equation was used for approximation of the change in the physical and mechanical properties of the samples depending on the number of cycles. It was shown that the values of the studied properties were affected most by the first soaking and drying cycles after which BS and MOE decreased continuously while the values of JH and TS stabilized. After 10 cycles the final values of BS, MOE, JH and TS accounted for 75-81%, 95%, 82% and 98.5% of the initial values, respectively.

  9. Impact of anthropogenic forest contamination on radioresistance of woody plant seed

    International Nuclear Information System (INIS)

    Radioresistance of seeds of bay willow (Salix pentandra L.) and great sallow willow (Salix caprea L.) from forests chronically affected and non-affected by acidic (SO2, NOx, HF, etc.) industries has been studied and compared. Bay willow seeds of 6 harvests showed no difference in radioresistance. However, seeds of both species manifested strong synchronous variability in resistance to preplant exposure. Also, no influence was observed of mother plant gas content on great sallow willow seeds of different harvests. Data obtained confirm similar results of previous studies conducted by the author (1987) to identify the impact of plant gas content on radioresistance of seeds and seedlings of pine (Pinus sylvestris L.) and birch (Betula verrucosa Erh.). (author)

  10. Biochemical and molecular genetic approaches on the radioprotective mechanism of natural products

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Hee; Lee, Eun Ju; Sung, Woo Kyung; Piao, Wen Hua [Kyunghee University, Seoul (Korea)

    1999-04-01

    We reported the radio-protective effect of DTT. The treatment of DTT increased cell survival after gamma-irradiation, decreased in the frequencies of micronucleus, and reduction in DNA fragmentation and apoptotic cells. Induction of apoptosis after UV-C irradiation was revealed by the changes in the relative cell death, increase in the relative amount of apoptotic cells, and the induction of DNA fragmentation. About 100 medicinal plants were purchased and methanol extract samples were prepared. Radio-protective and radio-sensitizing activities of these samples were screened. Seven samples showed above 20% radio-protective activities: Salvia miltiorrhiza, Areca catechu, Cornus officinalis, Alpiniae officinari rhizoma, Meliae fructus, Alpiniae katsumadaii semen, Betulae cortex. Acanthopanax sessiliflous showed the highest radio-sensitizing effect and 10 other samples revealed moderate activities: Melia japonica, Agastache rugosa, Platycodon gradiflorum, Broussonetia bazinoki, Angelica gigas, Inula helenium, Chelidonium majus, Pulsatilla koreana, Oldenlandia diffusa, Dioscorea batatas. (author). 49 refs., 9 figs., 7 tabs.

  11. Long-term forest dynamics at Gribskov, eastern Denmark with early-Holocene evidence for thermophilous broadleaved tree species

    DEFF Research Database (Denmark)

    Overballe-Petersen, Mette V; Nielsen, Anne Birgitte; Hannon, Gina E.;

    2012-01-01

    two periods of the early Holocene and from c. 3000 cal. BP to present. The early-Holocene part of the record indicates a highly disturbed forest ecosystem with frequent fires and abundant macrofossils of particularly Betula sp. and Populus sp. The sediment stratigraphy and age–depth relationships give......We report on a full-Holocene pollen, charcoal and macrofossil record from a small forest hollow in Gribskov, eastern Denmark. The Fagus sylvatica pollen record suggests the establishment of a small Fagus population at Gribskov in the early Holocene together with early establishment of other...... thermophilous broadleaved trees, including Quercus sp., Tilia sp. and Ulmus sp. The macrofossils contribute to the vegetation reconstruction with evidence for local presence of species with low pollen productivity or easily degraded pollen types such as Populus. The charcoal record shows frequent burning during...

  12. Enzymological study of the evolution of the technogenic soil submitted to biological recultivation in Bozanta Mare (Maramures county, north-western Romania

    Directory of Open Access Journals (Sweden)

    Cristian Felix BLIDAR

    2009-11-01

    Full Text Available This paper summarizes our research work regarding the dynamics of vegetation growth of miscellaneous species of trees planted and monitored in the particular environment of the tailing pond in Bozanta Mare (Maramures County. The structure of soil bearing high content of heavy metals and cyanides considerably impacts the ecologic conditions of tailing ponds. Aspects related to soil characteristics (such as structure, size of particles, porosity, texture, chemical composition are included. In the framework of our experiment we have planted seedlings belonging to four species of trees: Quercus petraea, Populus tremula, Betula verrucosa, Salix caprea. Our aim was to study the evolution of enzyme activities. Our contribution, based on the outcomes of our research, consists in the formulation of functional correlations spotted between cormophites and enzyme activities, between the species of trees and their environmental underlying conditions, with the overarching goal to optimize the activities undertaken in order to alleviate the tailing ponds inherent to mining activities.

  13. Determination of selected microelements in polish herbs and their infusions

    Energy Technology Data Exchange (ETDEWEB)

    Kalny, Piotr [Medical University of Warsaw, Department of Drugs Analysis, Banacha 1, 02-091 Warsaw (Poland); Fijalek, Zbigniew [Medical University of Warsaw, Department of Drugs Analysis, Banacha 1, 02-091 Warsaw (Poland); National Medicines Institute, Department of Pharmaceutical Chemistry, Chelmska 30/34, 00-725 Warsaw (Poland); Daszczuk, Anna [Medical University of Warsaw, Department of Drugs Analysis, Banacha 1, 02-091 Warsaw (Poland); Ostapczuk, Peter [Research Center of Juelich, Department of Safety and Radiation Protection, Leo-Brand Str. 1, D-52425 Juelich (Germany)]. E-mail: p.ostapczuk@fz-juelich.de

    2007-08-01

    Ba, Cd, Cr, Cu, Fe, Ni, Pb and Zn were determined in birch leaves (Folium Betulae), dandelion roots (Radix Taraxacae), hawthorn blossom (Inflorescentia Crataegi) and their infusions by graphite furnace atomic absorption spectrometry (GFAAS) after microwave digestion of plant samples. Infusions were made from herbs according to prescription for patients, provided by the producer of medicine on the package. The results obtained were compared with daily requirements for each element. Results show high content of cadmium in the medicinal plants analyzed. The highest level in infusions was observed for Ni and Zn (over 90% of the total element concentration for Ni and in most cases over 50% for Zn), and the lowest for Cd and Pb. The calculated daily intake of majority of the analyzed elements was very low (under 1% of daily requirements)

  14. Determination of selected microelements in polish herbs and their infusions

    International Nuclear Information System (INIS)

    Ba, Cd, Cr, Cu, Fe, Ni, Pb and Zn were determined in birch leaves (Folium Betulae), dandelion roots (Radix Taraxacae), hawthorn blossom (Inflorescentia Crataegi) and their infusions by graphite furnace atomic absorption spectrometry (GFAAS) after microwave digestion of plant samples. Infusions were made from herbs according to prescription for patients, provided by the producer of medicine on the package. The results obtained were compared with daily requirements for each element. Results show high content of cadmium in the medicinal plants analyzed. The highest level in infusions was observed for Ni and Zn (over 90% of the total element concentration for Ni and in most cases over 50% for Zn), and the lowest for Cd and Pb. The calculated daily intake of majority of the analyzed elements was very low (under 1% of daily requirements)

  15. The blocking activity of birch pollen-specific immunotherapy-induced IgG4 is not qualitatively superior to that of other IgG subclasses

    DEFF Research Database (Denmark)

    Ejrnaes, Anne M; Bødtger, Uffe; Larsen, Jørgen N; Svenson, Morten

    2004-01-01

    for the clinical efficacy of SIT. In this study, fractionated serum samples from 14 SIT-treated birch pollen allergic individuals enabled determination of the inhibitory capacity of IgG4 alone versus non-IgG4 IgG. Allergen-binding activities of IgG and the IgG-mediated inhibition of allergen binding...... to autologous IgE were detected using 125I-labelled rBet v 1.2801, a recombinant variant of the major allergen of Betula verrucosa pollen. Results show that IgG4-depletion resulted in equivalent reductions in binding and blocking activities. In contrast, a significant but less than two-fold higher...

  16. A longitudinal study of memory advantages in bilinguals.

    Directory of Open Access Journals (Sweden)

    Jessica K Ljungberg

    Full Text Available Typically, studies of cognitive advantages in bilinguals have been conducted previously by using executive and inhibitory tasks (e.g. Simon task and applying cross-sectional designs. This study longitudinally investigated bilingual advantages on episodic memory recall, verbal letter and categorical fluency during the trajectory of life. Monolingual and bilingual participants (n=178 between 35-70 years at baseline were drawn from the Betula Prospective Cohort Study of aging, memory, and health. Results showed that bilinguals outperformed monolinguals at the first testing session and across time both in episodic memory recall and in letter fluency. No interaction with age was found indicating that the rate of change across ages was similar for bilinguals and monolinguals. As predicted and in line with studies applying cross-sectional designs, no advantages associated with bilingualism were found in the categorical fluency task. The results are discussed in the light of successful aging.

  17. Slow pyrolysis of willow (Salix) studied with GC/MS and GC/FTIR/FID

    Energy Technology Data Exchange (ETDEWEB)

    Ingemarsson, A.; Nilsson, M.; Pedersen, J.R.; Olsson, J.O. [Chalmers University of Technology, Goeteborg (Sweden). Dept. of Physical Chemistry

    1999-07-01

    Small samples (15-150 mg) of wood and bark from basket willow (Salix viminalis) clone Jorr were pyrolysed at 550{sup o}C. Samples from pure wood of European White (Silver) Birch (Betula pendula (alba)) and Norway Spruce (Picea abies) were used as references. The compounds produced during pyrolysis were analysed using gas chromatographic (GC) methods: direct injection with GC/FTIR/FID, direct injection with GC/MS, and pre-concentration with GC/MS. The samples from salix, birch and spruce all produced a range of low molecular weight compounds: aliphatic acids, esters, aldehydes, and ketones as well as furans. Commonly, these samples also formed aromatic compounds: phenol, methyl-phenols, and the guiacol (2-Methoxyphenol) series of compounds. Salix and birch both produced the syringol (2,6-Dimethoxyphenol) series of compounds. Syringol derivatives were not detected from the pyrolysis of spruce. (author)

  18. PURIFICATION OF HARDWOOD-DERIVED AUTOHYDROLYSATES

    Directory of Open Access Journals (Sweden)

    Joni Tapani Lehto,

    2012-02-01

    Full Text Available Carbohydrate-containing hydrolysates (1.1 to 14.9% of wood dry matter obtained from autohydrolysis (at 130 to 150°C for 30 to 120 minutes of birch (Betula pendula chips prior to pulping were purified with respect to non-carbohydrate materials, without carbohydrate losses, either by ethyl acetate extraction or XAD-4 resin treatment. In the former case, about 50% of lignin and practically all the furanoic compounds (2-furaldehyde and 5-(hydroxymethylfurfural could be removed, whereas in the latter case, the corresponding amounts were about 30% and 50 to 90%, respectively. A partial recovery of various unsaturated impurities is of importance, because they may act as inhibitors when biochemically converting carbohydrates in hydrolysates into value-added products.

  19. Late glacial vegetation development in Denmark – new evidence based on macrofossil and pollen from Slotseng, a small-scale site in southern Jutland

    DEFF Research Database (Denmark)

    Mortensen, Morten Fischer; Birks, Hilary H.; Christensen, Charlie;

    2011-01-01

    This paper presents the first unambiguous terrestrial palaeoecological record for the late glacial “Bølling warming” in Denmark. Pollen and macrofossil stratigraphies from pre-Bølling to 10,800 cal yr BP are presented from a small kettle hole in Southwest Denmark, during which the lake basin...... developed from an immature stage after the deglaciation to complete infilling in the early Holocene. Results show that the recently deglaciated landscape bore a discontinuous vegetation of pioneer plants. After the Bølling warming, an open Dryas octopetala-Betula nana community developed with Helianthemum...... the Younger Dryas period trees disappeared and the vegetation became open again and dominated by subarctic species. Following climate warming at the Younger Dryas–Holocene transition a shrub community of Empetrum and Juniperus developed. After approximately 200 years it was replaced by birch forest...

  20. Comparative measurements of transpiration an canopy conductance in two mixed deciduous woodlands differing in structure and species composition

    DEFF Research Database (Denmark)

    Herbst, Mathias; Rosier, Paul T.W.; Morecroft, Michael D.;

    2008-01-01

    continuous hazel (Corylus avellana L.) understory. Wytham Woods, which had an LAI of 3.6, was dominated by ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.) and had only a sparse understory. Annual canopy transpiration was 367 mm for Grimsbury Wood and 397 mm for Wytham Woods. These values......Transpiration of two heterogeneous broadleaved woodlands in southern England was monitored by the sap flux technique throughout the 2006 growing season. Grimsbury Wood, which had a leaf area index (LAI) of 3.9, was dominated by oak (Quercus robur L.) and birch (Betula pubescens L.) and had a...... incoming solar radiation (RG) and the vapour pressure deficit (D). The response of gc to RG was similar for both forests. Both reference conductance (gcref), defined as gc at D = 1 kPa, and the stomatal sensitivity (-m), defined as the slope of the logarithmic response curve of gc to D, increased during...

  1. A 22 570-year record of vegetational and climatic change from Wenhai Lake in the Hengduan Mountains biodiversity hotspot, Yunnan, Southwest China

    Science.gov (United States)

    Yao, Y. F.; Song, X. Y.; Wortley, A. H.; Blackmore, S.; Li, C. S.

    2015-03-01

    The Hengduan Mountains, with their strong altitudinal vegetation zonation, form a biodiversity hotspot which offers the potential for comparison between sites in order to understand how this zonation arose and how it has responded to climate change and human impacts through time. This paper presents a 22 570-year pollen record of vegetational and climatic change based on a core 320 cm in depth collected from Wenhai Lake on Jade Dragon Snow Mountain, one of the highest peaks in the Hengduan Mountains region of Yunnan, Southwest China. From 22 570 to 21 140 cal yr BP, the vegetation was dominated by broad-leaved forest (comprising mainly Quercus, Betula and Castanopsis), accompanied by needle-leaved forest (mainly Pinus and Abies), indicating a rather cold and dry climate relative to the present followed by cold and wet conditions. In the period between 21 140 and 19 350 cal yr BP, the vegetation was still dominated by broad-leaved forest and needle-leaved forest as before but with a notable increase in Betula pollen and a sharp decrease in Quercus pollen, implying a relatively cold and dry climate with several fluctuations in humidity. The period 19 350 to 17 930 cal yr BP was a transition stage from broad-leaved forest to needle-leaved forest, with a dramatic decrease in Quercus pollen and a maximum reading for Abies pollen, reflecting the coldest and driest climate since 22 570 cal yr BP. The expansion in needle-leaved forest dominated by Pinus and Abies (22 570-17 930 cal yr BP) along with an increase of Betula might correspond to the Last Glacial Maximum (LGM; the start of the LGM perhaps occurred prior to the basal age of the core). Between 17 930 and 9250 cal yr BP, needle-leaved forest declined and broad-leaved forest began to increase at first, suggesting increases in temperature and humidity, while towards the end of the period, needle-leaved forest expanded and broad-leaved forest shrank, indicating a colder and drier climate, possibly corresponding to the

  2. Short communication. A review on the efficacy tests and risk analyses conducted on Chondrostereum purpureum, a potential biocontrol agent, in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Hantula, J.; Hamberg, L.; Vartiamaki, H.; Korhonen, K.; Uotila, A.

    2012-11-01

    Hardwood sprouting is a problem in forest regeneration areas, under electric lines, on roadsides and railways. In Finland, isolates of Chondrostereum purpureum were screened by field experiments for their efficiency to control sprouting. The proportion of dead stumps with the best isolates exceeded 80% on birch (Betula pendula and B. pubescens), and C. purpureum was also found to affect the sprouting of aspen (Populus tremula) and rowan (Sorbus aucuparia). The risks of C. purpureum based biocontrol were evaluated by population genetic analysis. It showed that C. purpureum is a geographically undifferentiated species that does not reproduce clonally. The risk of infection of non-target trees was found to be highest in early spring. These findings suggest that the risks of using C. purpureum in biocontrol are small. (Author) 36 refs.

  3. Spontaneous changes a basis for new ornamental woody plant cultivars

    Directory of Open Access Journals (Sweden)

    Đukić Matilda

    2006-01-01

    Full Text Available In nursery stock production of some ornamental woody plants the appearance of spontaneous variability was identified in the form of atypical pigmentation of leaves (albinism, variegated, red colored, leaves shape (jaggy and dwarfs. Mutated plants with variegated leaves were observed among hybrid plane (Platanus x acerifolia (Ait. Willd., Siberian elm (Ulmus pumila L., laurel cherry (Prunus laurocerasus L. and Lawson false-cypress (Chamaecyparis lawsoniana (Murr. Parl. Seedlings. The type of variegation and frequency were analyzed. Among plane tree and Siberian elm seedlings there were observed red colored leaves. Atypical, jaggy shaped leaves were found among laurel cherry seedlings. Dwarf growth was identified at Siberian elm and birch (Betula pendula Roth. where also found fruits at one year seedling. There were not significant differences in some morphological and physiological properties in plane tree seedlings with various pigmented leaves. .

  4. Is the Growth of Birch at the UPPER Timberline in the Himalayas Limited By Moisture or By Temperature?

    Science.gov (United States)

    Liang, E.; Dawadi, B.; Pederson, N.; Eckstein, D.

    2014-12-01

    Birch (Betula) trees and forests are found across much of the temperate and boreal zones of the Northern Hemisphere. Yet, despite being an ecologically-significant genus, it is much less-well studied compared to common genera like Pinus, Picea, Juniperus, Quercus, and Fagus. In the Himalayas, Himalayan birch (Betula utilis) is a widespread, important broadleaf timberline species that survives in mountain rain shadows via access to water from snowmelt. Because precipitation in the Nepalese Himalayas decreases with increasing elevation, we hypothesized that the growth of birch at the upper timberlines between 3,900 and 4,150 m a.s.l. is primarily limited by moisture availability rather than by low temperature. To verify this assumption, a total of 292 increment cores were extracted from 211 birch trees at nine timberline sites. The synchronous occurrence of narrow rings and high inter-series correlations within and among sites evidenced a reliable cross-dating and a common climatic signal in the tree-ring widths variations. From March-May, all nine tree-ring width site chronologies showed a strongly positive response to total precipitation and a less strongly negative response to temperature. During the instrumental meteorological record (after 1960), years with a high percentage of missing rings coincided with pre-monsoon drought events. Periods of below-average growth are in phase with well-known drought events all over monsoon Asia, showing additional evidence that Himalayan birch growth at the upper timberlines is persistently limited by moisture availability. Our study describes the rare case of a drought-induced altitudinal timberline that is composed by a broadleaf tree species.

  5. Late glacial multiproxy evidence of vegetation development and environmental change at Solova, southeastern Estonia

    Directory of Open Access Journals (Sweden)

    Amon, Leeli

    2010-06-01

    Full Text Available Reinvestigation of the late glacial Solova (Remmeski basin, based on plant macro­fossil and diatom record, AMS 14C chronology and sediment composition (loss-on-ignition and magnetic susceptibility data, provided information on vegetation history and palaeoenvironmental and palaeoclimatic changes since the time of the deglaciation of the area around 14 000 cal yr BP. The chronology of the sequence is based on seven AMS dates on terrestrial macrofossils, providing evidence of rapid sedimentation in between 14 000 and 13 500 cal yr BP. Loss-on-ignition data show a clear short-lived warming episode centred to 13 800 cal yr BP, tentatively correlated with the GI-1c warming of the event stratigraphy of the Last Termination in the North Atlantic region, which suggests that at least parts of the Haanja Heights were ice-free by 14 000 cal yr BP. Macrofossil evidence indicates Betula nana–Dryas octopetala-dominated open tundra communities with Saxifraga on dry ground, and Carex sp. and Juncus on wet ground at that time. The first evidence of the postglacial presence of tree birch (Betula pendula in Estonia is dated back to 13 500 cal yr BP. However, conifer remains were not found in the late glacial sediment sequence of Solova Bog. The late-Allerød (GI-1a organic deposits, which are quite typical of other parts of Estonia and indicate general warming, are missing at Solova, most probably due to a hiatus in sedimentation in this very small and shallow upland basin.

  6. THE WATER CONSERVATION OF THE MAJOR FOREST TYPES OF DAQING MOUNTAIN IN INNER MONGOLIA%内蒙古大青山主要林分类型水源涵养能力研究

    Institute of Scientific and Technical Information of China (English)

    王冬至; 张秋良; 陈高娃; 青梅

    2012-01-01

    In this paper, the canopy interception, water holding capacity of litter and soil moisture level was observed in natural pine forest and the different ages of secondary birch, and the observation data were analyzed by SAS data processing software. The regression equation of natural rainfall and canopy interception was established. The result shows that soil water holding capacity is increasing from the Pinus tabulaeformis plantation andyoung-aged forest、middle -aged forest、matured forest of Betula platyphylla natural secondary forest, but there is a downward trend as soil depth increased. Soil water holding capacity of Betula platyphylla natural secondary forest is higher than that of Pinus tabulaeformis plantation.%本文对研究区的油松人工林和天然白桦次生林不同林龄的林冠截留量、枯落物持水量及土壤层的持水量进行了观测,并通过SAS数据处理软件对观测数据进行了分析.建立了自然降雨与林冠截留的回归方程,不同分解程度枯落物持水比率及持水速率的表达式,并对不同林分类型土壤持水量进行多重比较分析,结果显示油松人工林和天然白桦次生林的幼龄林、中龄林、成熟林土壤持水量依次增大并随着土层深度的增大持水能力呈下降趋势,天然白桦次生林的土壤持水量高于人工油松林.

  7. 黑河地区不同优势树种林下枯落物量的比较%Comparing the Litter Amounts under Dominant Tree Species of Heihe District

    Institute of Scientific and Technical Information of China (English)

    孙元发; 吴铭

    2014-01-01

    枯落物是森林生态系统物质循环的一个重要组成部分,具有极为重要的水文功能,枯落物水文生态功能的发挥首先取决于枯落物的量。通过对黑河地区不同优势树种林下枯落量的调查与测定,结果表明:黑河地区各种优势树种中,落叶松的单位面积上枯落物总干质量最大,达到5.46 t 灋hm -2,而樟子松的单位面积上枯落物总干质量最小,只有1.08t 灋hm -2,赤杨、山杨、柞树、白桦、黑桦单位面积上枯落物总干质量为2.93~4.9t 灋hm -2。%Litter is an important constituent part in forestry ecosystem cycle ,with vital hydrological function ,which is determined primarily by litter amount .In this work ,litter amount under dominant tree species of Heihe district was surveyed .The result manifested litter amount of unit area was highest under Larix gmelinii ,up to 5 .46 t · hm -2 , while it was lowest under Pinus sylvestris ,only with 1 .08 t · hm -2 .Under A lnus japonica ,Populus davidiana , Quercus mongolica ,Betula platyphylla ,Betula dahurica ,it was from 2 .93 to 4 .9 t · hm -2 .

  8. Rapid carbon turnover beneath shrub and tree vegetation is associated with low soil carbon stocks at a subarctic treeline.

    Science.gov (United States)

    Parker, Thomas C; Subke, Jens-Arne; Wookey, Philip A

    2015-05-01

    Climate warming at high northern latitudes has caused substantial increases in plant productivity of tundra vegetation and an expansion of the range of deciduous shrub species. However significant the increase in carbon (C) contained within above-ground shrub biomass, it is modest in comparison with the amount of C stored in the soil in tundra ecosystems. Here, we use a 'space-for-time' approach to test the hypothesis that a shift from lower-productivity tundra heath to higher-productivity deciduous shrub vegetation in the sub-Arctic may lead to a loss of soil C that out-weighs the increase in above-ground shrub biomass. We further hypothesize that a shift from ericoid to ectomycorrhizal systems coincident with this vegetation change provides a mechanism for the loss of soil C. We sampled soil C stocks, soil surface CO2 flux rates and fungal growth rates along replicated natural transitions from birch forest (Betula pubescens), through deciduous shrub tundra (Betula nana) to tundra heaths (Empetrum nigrum) near Abisko, Swedish Lapland. We demonstrate that organic horizon soil organic C (SOCorg ) is significantly lower at shrub (2.98 ± 0.48 kg m(-2) ) and forest (2.04 ± 0.25 kg m(-2) ) plots than at heath plots (7.03 ± 0.79 kg m(-2) ). Shrub vegetation had the highest respiration rates, suggesting that despite higher rates of C assimilation, C turnover was also very high and less C is sequestered in the ecosystem. Growth rates of fungal hyphae increased across the transition from heath to shrub, suggesting that the action of ectomycorrhizal symbionts in the scavenging of organically bound nutrients is an important pathway by which soil C is made available to microbial degradation. The expansion of deciduous shrubs onto potentially vulnerable arctic soils with large stores of C could therefore represent a significant positive feedback to the climate system. PMID:25367088

  9. Environmental variability in the monsoon-westerlies transition zone during the last 1200 years: lake sediment analyses from central Mongolia and supra-regional synthesis

    Science.gov (United States)

    Tian, Fang; Herzschuh, Ulrike; Dallmeyer, Anne; Xu, Qinghai; Mischke, Steffen; Biskaborn, Boris K.

    2013-08-01

    A high resolution multi-proxy (pollen, grain size, total organic carbon) record from a small mountain lake (Lake Khuisiin; 46.6°N, 101.8°E; 2270 m a.s.l.) in the south-eastern Khangai Mountains of central Mongolia has been used to explore changes in vegetation and climate over the last 1200 years. The pollen data indicates that the vegetation changed from dry steppe dominated by Poaceae and Artemisia (ca AD 760-950), to Larix forest steppe (ca AD 950-1170), Larix-Betula forest steppe (ca AD 1170-1380), meadow dominated by Cyperaceae and Poaceae (ca AD 1380-1830), and Larix-Betula forest steppe (after ˜ AD 1830). The cold-wet period between AD 1380 and 1830 may relate to the Little Ice Age. Environmental changes were generally subtle and climate change seems to have been the major driver of variations in vegetation until at least the early part of the 20th century, suggesting that either the level of human activity was generally low, or the relationship between human activity and vegetation did not alter substantially between AD 760 and 1830. A review of centennial-scale moisture records from China and Mongolia revealed that most areas experienced major changes at ca AD 1500 and AD 1900. However, the moisture availability since AD 1500 varied between sites, with no clear regional pattern or relationship to present-day conditions. Both the reconstructions and the moisture levels simulation on a millennium scale performed in the MPI Earth System Model indicate that the monsoon-westerlies transition area shows a greater climate variability than those areas influenced by the westerlies, or by the summer monsoon only.

  10. High environmental variability in the monsoon-westerlies transition area of Asia during the last 1200 years: lake sediment analyses from central Mongolia and supra-regional synthesis

    Science.gov (United States)

    Tian, Fang; Herzschuh, Ulrike; Dallmeyer, Anne; Xu, Qinghai; Mischke, Steffen; Biskaborn, Boris K.

    2013-04-01

    A high resolution multi-proxy (pollen, grain size distribution, total organic carbon) record from a small mountain lake (Lake Khuisiin; 46.6°N, 101.8°E; 2270 m a.s.l.) in the south-eastern Khangai Mountains of central Mongolia has been used to explore changes in vegetation and climate over the last 1200 years. The pollen data indicates that the vegetation changed from dry steppe dominated by Poaceae and Artemisia (ca. AD 760-950), to Larix forest steppe (ca. AD 950-1170), Larix-Betula forest steppe (ca. AD 1170-1380), meadow dominated by Cyperaceae and Poaceae (ca. AD 1380-1830), and Larix-Betula forest steppe (after ~AD 1830). There was no consistent evidence of warming during the Medieval Warm Period, but the cold wet period between AD 1380 and 1830 may relate to the Little Ice Age. Environmental changes were generally subtle and climate change seems to have been the major driver of variations in vegetation until at least the early part of the 20th century, suggesting that either the level of human activity was generally low, or the relationship between human activity and vegetation did not alter substantially between AD 760 and 1830. A review of centennial-scale moisture records from China and Mongolia revealed that most areas experienced major changes at ca. AD 1500 and AD 1900. However, the moisture availability since AD 1500 varied between sites, with no clear regional pattern or relationship to present-day conditions. Both the reconstructions and the moisture levels simulation on the millennium scale preformed in the MPI Earth System Model indicate that the monsoon-westerlies transition area shows a higher climate variability than the areas purely influenced by the westerlies or the summer monsoon.

  11. Free atmospheric CO2 enrichment increased above ground biomass but did not affect symbiotic N2-fixation and soil carbon dynamics in a mixed deciduous stand in Wales

    Directory of Open Access Journals (Sweden)

    A. R. Smith

    2011-02-01

    Full Text Available Through increases in net primary production (NPP, elevated CO2 is hypothesized to increase the amount of plant litter entering the soil. The fate of this extra carbon on the forest floor or in mineral soil is currently not clear. Moreover, increased rates of NPP can be maintained only if forests can escape nitrogen limitation. In a Free atmospheric CO2 Enrichment (FACE experiment near Bangor, Wales, 4 ambient and 4 elevated [CO2] plots were planted with patches of Betula pendula, Alnus glutinosa and Fagus sylvatica on a former arable field. After 4 years, biomass averaged for the 3 species was 5497 (se 270 g m−2 in ambient and 6450 (se 130 g m−2 in elevated [CO2] plots, a significant increase of 17% (P = 0.018. During that time, only a shallow L forest floor litter layer had formed due to intensive bioturbation. Total soil C and N contents increased irrespective of treatment and species as a result of afforestation. We could not detect an additional C sink in the soil, nor were soil C stabilization processes affected by elevated [CO2]. We observed a decrease of leaf N content in Betula and Alnus under elevated [CO2], while the soil C/N ratio decreased regardless of CO2 treatment. The ratio of N taken up from the soil and by N2-fixation in Alnus was not affected by elevated [CO2]. We infer that increased nitrogen use efficiency is the mechanism by which increased NPP is sustained under elevated [CO2] at this site.

  12. Study on complexity of plant communities at different altitudes on the Northern Slope of Changbai Mountain

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    By the method of gradient pattern analysis, twenty plots were set at altitudes of 700-2600 m with an interval of 100 m on the northern slope of the Changbai Mountain. The dissimilarity of respective sub-plots in the same community was measured and the complexity of plant communities at different altitudes was analyzed. The result from binary data of tree species in canopy tree indicated that the sub-plots in the communities, except subalpine Betula ermanii forest, showed comparatively high dissimilarity in species composition. Especially, the dissimilarity index (0.7) of broadleaved/Korean pine forest at low altitudes was obviously higher than other communities. The differences are not obvious between communities referring to dark coniferous forest. Comparatively, the dissimilarity in sub-plots of the communities at altitude of 1400 m was slightly higher than that of other communities, which reflected the complexity of tree species compositions of transitory-type communities. For subalpine Betula ermanii forest, tree species composition was simple and showed a high similarity between sub-plots. The results derived from binary data of shrub showed that the dissimilarity index of shrub species in broadleaved/Korean pine forest at low altitudes was higher than that in other communities, but the divergence tendency wasn't so obvious as that of arbor species. The dissimilarity derived from binary data of herb and all plant species at different altitudes showed greatly close tendency, and the differences in herb and all plant species between sub-plots were the greatest for the communities of broad-leaved-Korean pine forest and alpine tundra zone.

  13. Systematics of the ectomycorrhizal genus Lactarius in the Rocky Mountain alpine zone.

    Science.gov (United States)

    Barge, Edward G; Cripps, Cathy L; Osmundson, Todd W

    2016-03-01

    Lactarius (Russulales) is an important component of ectomycorrhizal fungal communities in cold-dominated contiguous arctic and disjunct alpine habitats where it associates primarily with Betula, Dryas and Salix However, little is known of this genus in the central and southern Rocky Mountain alpine zone (3000-3900 m) of North America. Molecular phylogenetic analyses of nuc rDNA ITS1-5.8S-ITS2 (ITS barcode) and the second largest subunit of the RNA polymerase II gene (RPB2) partial sequences in conjunction with detailed morphological examination confirm at least six species occurring above treeline. Most have intercontinental distributions in North America and Eurasia according to molecular comparison with type material and collections from Europe, Fennoscandia, Svalbard and Alaska. Rocky Mountain collections of L. lanceolatus (subgenus Russularia), along with the type from Alaska are paraphyletic with respect to L. aurantiacus and North American taxa L. luculentus and L. luculentus v. laetus Rocky Mountain collections of L. nanus, L. glyciosmus, L. repraesentaneus and L. salicis-reticulatae (subgenus Piperites) all form clades with European material from type localities and other arctic-alpine habitats. The arctic-alpine L. pseudouvidus/L. brunneoviolaceus group appears to be a complex containing additional taxa. North American material originally described as part of this group is well-separated phylogenetically and is described here as L. pallidomarginatus sp. nov. Lactarius lanceolatus, L. nanus and L. salicis-reticulatae appear largely restricted to arctic-alpine habitats with Salix Lactarius glyciosmus and L. repraesentaneus occur in arctic-alpine, subalpine and boreal habitats with Betula and also Picea and possibly Salix for the latter. Species distributions are hypothesized to be shaped by host ranges, glaciation and long distance dispersal. PMID:26740539

  14. Plant Diversity and Its Elevational Gradient Patterns in Wulu Mountain, Shanxi, China%山西五鹿山植物物种多样性及其海拔梯度格局

    Institute of Scientific and Technical Information of China (English)

    曲波; 苗艳明; 张钦弟; 毕润成

    2012-01-01

    Samplings were gathered and examined in forests along altitudinal gradients of Wulu Mountain, China. The results indicated that the major communities in the forests can be classified as Quercus wutaishanica, Pinus labulaeformis, Acer ginnala, Betula platyphylla, Pinus bungeana, Syringa reticulate- Acer ginnala and Betula platyphylla community. Our research suggests that the Quercus wutaishanica community appears to be a dominant community in a successional stage toward temperate deciduous broad-leaved forests. The species richness in different layers of these communities can be distinguished as, herb layer > shrub layer > tree layer. Both the Shannon-Wiener diversity index and Simpson diversity index showed similar patterns. The species diversity indices of different layers and overall importance value of the forest communities indicate that the forests appear to be successional and sub-climax communities in Wulu Mountain. Our research also suggests that there is a peak with higher species diversity index in the communities of middle elevation. We suggested that the pattern could be affected by temperature, moisture , and human disturbance. The pattern could also be influenced by the nature of successional stages and sub-climax communities.%采用典型取样法,沿海拔梯度对五鹿山自然植被进行调查.结果表明:五鹿山主要群落类型为辽东栎(Quercus wutaishanica)群落、油松(Pinus tabulaeformis)群落、茶条槭(Acer ginnala)群落、白皮松(Pinus bungeana)群落、暴马丁香-茶条槭(Syringa reticulate-Acer ginnala)群落和白桦(Betula platyphylla)群落.其中,辽东栎群落略占优势,这可能暗示着该地区植被具有继续向暖温带落叶阔叶林演替的倾向.各层次植物物种丰富度呈现出草本层>灌木层>乔木层特征,Shannon-Wiener多样性指数和Simpson多样性指数整体规律为草本层>灌木层>乔木层.以五鹿山森林群落不同层次的各种物种多样性指数和森林

  15. Airborne pollen spectrum of Dnіpropetrovsk city as a basis of hay fever control

    Directory of Open Access Journals (Sweden)

    V. V. Rodinkova

    2013-02-01

    other representatives of Asteraceae constituted of 5% each. The most abundant tree pollen rain (4% from total annual count was produced by the Populus species. Betula pollen was the next having up 2% of annual pollen rain in Dnipropetrovsk. As can be seen, the first arboreal spring-summer pollination wave was not massive in Dnipropetrovsk. It was represented by Populus, Betula, Acer, Fraxinus, Quercus, Ulmus, Pinus, Juglans pollen spread in the end of March, whole April and the first weeks of May mostly. However, the second wave was intensively seen from the mid of July till the mid of October. Important airborne pollen producing taxa were Artemisisia, Ambrosia, Asteraceae, Chenopodiaceae, Urtica, Plantago, Polygonaceae pollen at that time. Important airborne pollen allergens of Poaceae family (grasses held the 7th position in the total annual pollen rain and were recorded between two pollination waves from the mid of May till the end of June mostly. The worst period for the patients was associated with the Betula, Acer and Quercus pollination from 13th of April  till the mid of May and with Ambrosia and Artemisia pollination from 28th of July, till September, 30. The present airborne pollen calendar should be considered while diagnosing the hay fever symptoms in sensitive patients. It’s important to continue the pollen count and control in Dnіpropetrovsk due to constant changing of climatic and anthropogenic conditions impacting the pollen production and release.

  16. 高原湿地纳帕海周边山地不同植被类型枯落物持水特性%Water Holding Characteristics of Litters of Different Species in Mountainous Area of Napahai Plateau Wetland

    Institute of Scientific and Technical Information of China (English)

    陆梅; 田昆; 赖建东; 赵一鹤; 魏江舟

    2011-01-01

    The water holding capacity was characterized for the litters from eight plantation types in the mountainous area of Napahai Plateau Wetland. The results show that, for all the eight plantation types, the semi-decomposed and decomposed layer had higher litter storage and water reserving capacity than the freshly-littered layer. The litter storage decreased from highwood, shrub to waste grassland. Specifically, the litter storages of natural Picea asperata Mast, mixed forest of Pinus densata Mast and Rhododendron simsii Planch, mixed forest of Salix cupularis Rehd and Betula platyphylla Suk, Crataegus pinnatifida Bge and waste grassland demonstrated a capacity of 36.60, 30.67, 26.63, 25.61 and 5. 30 t/hm2 , respectively. Comparatively, mixed forest of Salix cupularis Rehd and Betula platyphylla Suk had the highest water holding capacity, and seriously human-disturbed Pinus densata Mast had the lowest. The water holding capacity of the litters increased rapidly during the initial first hour, and then slightly increased after 6~10 hour saturation. The highest water absorption rates were observed in the first 30 minute saturation time, and thereafter the rates decreased substantially. Water loss rates were similar for all the litters, showing a linear decreasing trend. Systematic analysis indicated that the litter of mixed forest of Salix cupularis Rehd and Betula platyphylla Suk had the highest water holding capacity, the strongest flood-adjusting capacity, the most ideal water loss process and the highest water supply capacity, and the best hydro-ecological effect among the eight plantation types.%对高原湿地纳帕海周边山地8种不同植被类型枯落物持水特性进行了研究.结果表明,(1)8种植被类型枯落物储量和总持水量均表现出半分解+分解层>未分解层的变化趋势;枯落物储量呈现从乔木林到灌木林和荒草地逐渐降低的总体趋势;高山柳+白桦混交林最大总持水量最大,受人为干扰较为

  17. CUTICULAR STRUCTURE OF TWO ANGIOSPERM FOSSILS IN NEOGENE FROM TENGCHONG, YUNNAN PROVINCE AND ITS PALAEOENVIRONMENTAL SIGNIFICANCE%云南腾冲新近纪两种被子植物化石的角质层构造及其古环境意义

    Institute of Scientific and Technical Information of China (English)

    孙柏年; 丛培允; 阎德飞; 解三平

    2003-01-01

    This paper emphatically describes the cuticular characteristics of two fossil angiosperm species Betula mioluminifera Hu et Chaney and Carpinus subcordata Nathorst collected from Neogene in Tengchong, Yunnan. The cuticular characteristics of their Nearest Living Relative species (NLR species), Betula luminifera Winkler and Carpinus cordata B1.var. mollis Cheng et Chen, are analysed. In this experiment, we have got the lower epidermis of C.subcordata, whose characteristics are described as follows: Only the middle and lower parts of leave preserved; length about 7.5 cm, width 5 cm. Midrib strong; angle between ventricumbent and midrib 40°-50°; nearer to the base, bigger the angle; venulose, more than 12 pairs. Upper epidermis a little thicker and net-veined, stomata not found; epidermic cells arrayed rotundly, polygonal, length and width 20-30 μm; length of the net about 350 μm, width about 200 μm; width of nervecourses 50 μm with 3-4 rows of parallel cells; cells in nervecourses oblong, length about 2-3 times of width. Lower epidermis thin with stomata; trichome found; arrangement of epidermic cells as the same of upper epidermis. Distribution of stomata ruleless; type of stomatal apparatus Anomocytic; stomata slightly sunken; guard cells kidney-shaped and slightly lower than surrounding cells; inner surface of guard cells thick; guard cell surrounded by several epidermic cells. The cuticle, with its stomatal pores, represents the interface between plants and atmosphere, and its features such as cuticle thickness, stomatal density (SD), stomatal index (SI) and stomatal ratio (SR) are well used as a palaeoenvironmental indicator. Therefore, we can analyse changes in palaeoenvironment by studying the stomatal parameter of fossil plants which are sensitive to the change in atmospheric CO2 concentration. In this experiment, we have got the stomatal parameter of C.subcordata which indicates that atmospheric CO2 concentration in Neogene was higher than that of

  18. Late Miocene (Pannonian) Vegetation from the Northern Part of Central Paratethys

    Science.gov (United States)

    Kováčová, M.; Doláková, N.

    2009-04-01

    During Late Miocene, the Western Carpathian paleogeography started to change. The Lake Pannon retreated southwards, and the northern coast of the back arc basin was slightly elevated due to progradation of deltaic and alluvial facies, especially in the lowlands. The studied „Pannonian lake" sediments come from the Czech and Slovak parts of Central Paratethys. Changes of the sedimentary environment from deep to shallow lake and deltaic environment, followed by development of alluvial plains were noticed. Salinity crisis due to Paratethys isolation led to development of total freshwater environment to the end of this period. Samples from 3 surficial localities and 15 boreholes were palynologically studied. Occasional occurences of Dinoflagellates indicate a slightly higher salinity, whereas green algae Pediastrum, aquatic ferns Azolla, and aquatic and coastal plants (Nelumbo, Nymphaea, Myriophyllum, Sparganium, Potamogeton, Cyperaceae etc.) represent a freshwater environment. Due to paleogeographic changes and climatic oscillations the number of thermophilous taxa decreased and some of them disappeared completely from this area (f. e. Sapotaceae, Palmae). Mostly broad-leaved deciduous elements of mixed mesophytic forests (Quercus, Celtis, Carya, Tilia, Carpinus, Betula, Juglans) with some thermophilous elements admixture of Engelhardia, Castanea, Trigonobalanopsis, Symplocos, Cornaceaepollis satzveyensis generally dominate. Variously high relief of the uplifted mountainy chains created ideal conditions for higher presence of extrazonal vegetation (Cedrus, Tsuga, Picea, Cathaya) in the investigated area. Zonal type of vegetation including marshes, riparian forests with Alnus, Salix, Pterocarya, Liquidambar, Betula, Fraxinus, shrubs and lianas on dryer substrates associated riparian forest (Buxus, Ericaceae, Vitaceae, Lonicera, Rosaceae type Rubus), and coastal swamps with Taxodiaceae, Nyssa, Myrica, Sciadopitys were growing in the floodplain lowlands of Vienna Basin

  19. Osmolality and non-structural carbohydrate composition in the secondary phloem of trees across a latitudinal gradient in Europe

    Directory of Open Access Journals (Sweden)

    Anna eLintunen

    2016-06-01

    Full Text Available Phloem osmolality and its components are involved in basic cell metabolism, cell growth, and in various physiological processes including the ability of living cells to withstand drought and frost. Osmolality and sugar composition responses to environmental stresses have been extensively studied for leaves, but less for the secondary phloem of plant stems and branches. Leaf osmotic concentration and the share of pinitol and raffinose among soluble sugars increase with increasing drought or cold stress, and osmotic concentration is adjusted with osmoregulation. We hypothesize that similar responses occur in the secondary phloem of branches. We collected living bark samples from branches of adult Pinus sylvestris, Picea abies, Betula pendula and Populus tremula trees across Europe, from boreal Northern Finland to Mediterranean Portugal. In all studied species, the observed variation in phloem osmolality was mainly driven by variation in phloem water content, while tissue solute content was rather constant across regions. Osmoregulation, in which osmolality is controlled by variable tissue solute content, was stronger for Betula and Populus in comparison to the evergreen conifers. Osmolality was lowest in mid-latitude region, and from there increased by 37% towards northern Europe and 38% towards southern Europe due to low phloem water content in these regions. The ratio of raffinose to all soluble sugars was negligible at mid-latitudes and increased towards north and south, reflecting its role in cold and drought tolerance. For pinitol, another sugar known for contributing to stress tolerance, no such latitudinal pattern was observed. The proportion of sucrose was remarkably low and that of hexoses (i.e. glucose and fructose high at mid-latitudes. The ratio of starch to all non-structural carbohydrates increased towards the northern latitudes in agreement with the build-up of osmotically inactive C reservoir that can be converted into soluble

  20. Influence of aerogenic contamination on phytoncide activity of woody plants

    Directory of Open Access Journals (Sweden)

    S. O. Volodarez

    2015-07-01

    Full Text Available The main objective of this paper is to determine variations of antimicrobial activity of the volatile organic compounds from leaves of woody plants, which are growing on the areas with the different air pollution degree in the south-east of Ukraine. The research objects were Aesculus hippocastanum L., Betula pendula Roth, Salix alba L., Picea pungens Engelm. in Donetsk, Ukraine, and 6 species (Betula pendula Roth, Fraxinus excelsior L., Robinia pseudoacacia L., Populus nigra L., Tilia cordata Mill., Picea pungens Engelm. in Kramatorsk, Ukraine. Samples were collected in Donetsk every month during 2012 and 2013 years on four sample areas. Three research areas border with Donetsk Metallurgical Plant PSC, heavy traffic road and Kalinin coal mine, that feature such pollutants as CO2, SO2, NO2, and marsh gas. The fourth research area is the recreation zone (Donetsk Culture and Leisure Park near Donbass Arena stadium. The control area is located in the Donetsk Botanical Garden. The leaves from trees in Kramatorsk were collected in July and August 2013 on the sample area. The research area borders with Novokramatorsk Machine-building Plant JSC, which also features CO2, SO2, NO2 and other pollutants. The control area is located in the Jubilejnyi park. The research proves that antimicrobial activity of the volatile organic compounds from leaves of species under studyis sensitive to the impact of pollutants. Moreover, the antimicrobial activity of leaves B. pendula, S. alba, F. excelsior, R. pseudoacacia, P. nigra increases under the influence of pollutants from metallurgical plants and traffic exhausts. The antimicrobial ability of A. hippocastanum, T. cordata and P. pungens enhances in the areas with the cleaner air. These species are not gas-resistant species. Consequently, gas-resistant species feature the higher antimicrobial activity in the conditions of contamination. The other benefit of this study consists in monitoring of the seasonal

  1. Microbial Diversity of Primary Korean Pine Forests and Artificial Forests in Liangshui National Natural Reserve%凉水自然保护区原始红松林与人工林土壤微生物多样性

    Institute of Scientific and Technical Information of China (English)

    郭彦萃; 熊毅; 张志

    2013-01-01

    采用BIOLOG微平板法,研究了小兴安岭凉水国家自然保护区内原始红皮云杉( Picea koraiensis Na-kai)红松林、青楷槭( Acer tegmentosum Maxim.)红松林与人工兴安落叶松( Larix gmelini Rupr.)林、白桦( Betula platyphylla Suk.)林土壤微生物多样性特征。结果表明:各林型土壤微生物AWCD值随土层深度与季节变化表现为,在表层与0~10 cm土层中,四季2种原始红松林均高于人工林;在>10~20 cm土层中以人工林在春、夏、秋三季最高,冬季仍以原始红松林最高。不同土层的3种微生物多样性指数均以青楷槭红松林最高,且显著高于2种人工林。可见,原始阔叶红松林土壤微生物比原始针叶红松林及人工林土壤微生物具有更丰富的多样性。%By BIOLOG microplate method, an investigation was conducted to study the soil microbial diversity characteristics of Picea.koraiensis Nakai, Acer tegmentosum Maxim, artificial Larix.gmelini Rupr.and Betula platyphylla Suk.in Liang-shui National Nature Reserve, Xiaoxing’an Mountain.The soil microbial AWCD values of the forest-type varied with soil depth and seasons:in the surface and 0-10 cm layer of soil, it was highest in two original Korean pine forest throughout the year;in the 10-20 cm layer of soil, it was highest in plantation in spring, summer and autumn, while it was highest in the primitive Korean pine forest in winter;three different soil microbial diversity indexes of all soil layers were highest in Acer tegmentosum Maxim forest, and significantly higher than those of two plantation.Therefore, the soil microbial diversi-ty of original Broad-leaved Korean Pine forest is richer than that of the original coniferous Korean pine forest and planta-tion.

  2. Leaf and twig litter decomposition of main species in different forests along the north slope of Changbai Mountain,northeast China

    Institute of Scientific and Technical Information of China (English)

    GUO Zhongling; LI Qingkang; ZHENG Jinping; LIU Wande; FAN Chunnan; MA Yuandan; YU Guirui; HAN Shijie

    2007-01-01

    From 2001 to 2003,the litter decomposition dynamics of dominant tree species were conducted using a litterbag burying method in the broadleaf-Korean pine forest,spruce-fir forest and Ermans birch forest,which represents three altitudinal belts in Changbai Mountain,northeast China.The spatial and temporal dynamics of litter decomposition and the effects of litter properties were examined.Furthermore,the decomposition trend of different species was simulated by the Olson model,and results showed that annual mass loss rates increased over time,but was not significantly correlated.Leaf decomposition rates increased after decomposing for 638 days (1.75 years),and the order of dry weight remaining rates of leaf litter for different species is:Asian white birch (Betula platyphylla) (24.56%)<Amur linden (Tilia amurensis) (24.81%) < Korean pine (Pinus koraiensis)(38.48%)<spruce (Picea jezoensis var. microsperma)(41.15%)< Ermans birch (Betula ermanii) (41.53%)<fir (Abies nephrolepis) (42.62%).The dry weight remaining rates of twig litter was smaller than that of leaf litter,and followed the order of Amur linden (44.98%)<fir (64.62%)<Korean pine (72.07%)<spruce (73.51%)<Asian white birch (77.37%)<Ermans birch (80.35%).The simulation results by the Olson model showed that,in leaf,the 95%-decomposition rates ranged from 4.5 to 8.0 years,and annual decomposition rate (k) followed the order of Amur linden (0.686)>Asian white birch (0.624)>Korean pine (0.441)>spruce (0.406)>fir (0.397)>Ermans birch (0.385);in twig,it ranged from 7.8 to 29.3 years,and k follows the order:Amur linden (0.391)>fir (0.204)>Korean pine (0.176)>spruce (0.157)>Asian white birch (0.148)>Ermans birch (0.102).In general,the differences of decomposition rate are evident between leaf and twig litter and among species,and were higher in broad-leaved species compared with coniferous species at the same elevation,and decreased with the ascending of elevation.

  3. Features of secondary birch young stands in low mountain Pokuttya (Ukrainian Carpathian mts.

    Directory of Open Access Journals (Sweden)

    S. Y. Milevskaya

    2015-06-01

    Full Text Available Forest landscapes of the region during the last 3–5 centuries undergone the profound anthropogenic transformation. Secondary young stands occupy 25% of the total forest area. The problem of derivatives is particularly relevant for the modern forest typology in the Carpathian region. It requires the reflection in its dynamic trends shaping the stands, especially mixed young stands. The aim of our study consisted in getting the knowledge of the structural features of the secondary phytocoenosis of birch young stands in this area.The object of the study was age class I saplings growing in the mountainous part of Pokuttya, particularly in the basin of the Lutshka River. The conceptual basis of our study is the modern dynamic vision that every forest type is a consecutive series of forest plant communities within each type of homogeneous growing conditions. We apply methods of ecological-floristic research of the Brown-Blanke school in the interpretation of the Polish school phytosociology. However we also take into account both syntaxonomy generalizations of the Ukrainian scientists. The actual material comprises the original geobotanical studies with fixation of the vast majority of species in plant communities. Mainly the species having diagnostic value to separate syntaxons were taken into account in the analytical processing. Young forest stands (with the height of 8–12 m and crown cover of 70% together form the trees Betula pendula and B. pubescens. Fairly numerous admixture is formed by trees Alnus incana; besides, there are Fagus sylvatica, Populus tremula, Quercus robur, Padus avium. For dominants, they can be called “grey-alder birch blackberry sedge bracken fern” – Betula pendula+Alnus incana–Rubus caesius–Carex brizoides+Pteridium aquilinum. It is rich in floristic composition of the plant communities. They contain at least 12 species of trees, 3 species of shrubs, 4 species of bushes and 89 species of herbs. Diagnostic

  4. 基于CCA排序的霍山森林植物功能型划分%Classification of Plant Functional Types Based on CCA Ordination in Forest at Huoshan Mountain

    Institute of Scientific and Technical Information of China (English)

    丁献华; 毕润成; 闫明

    2011-01-01

    采用群落生态学的调查方法,在霍山七里峪设置80个样方并采集土壤样品.通过计算重要值和测定土壤理化性质(pH值、含水量、有机质含量、N、P、K含量),建立样方×物种矩阵和样方×环境矩阵,用CCA排序划分植物功能型.结果表明,随着海拔等环境因子的变化,可以将七里峪天然次生林划分为:F1山核桃Carya cathayensis Sarg.、虎榛子Ostryopsis davidiana Decaisne、披针叶苔草Carex lanceolata Boott.;F2油松Pinus tabulaeformis Carr.、三裂绣线菊Spiraea trilobata Linn.、荩草Arthraxon hispidus(Thunb.)Makio.;F3辽东栎Quercus wutaishanica Blume、连翘Forsythia suspensa(Thunb.)Vahl.Enum.、披针叶苔草;F4华北落叶松Larix principis-rupprechtii Mayr.、美丽胡枝子Lespedeza formosa(Vog.)Koehne、林荫千里光Senecio nemorensis Linn;F5 白桦Betula platyphylla Suk、毛榛子Corylus heterophylla Fisch.Ex Trautv.、披针叶苔草5个功能型.%This thesis adopted the investigation method of community ecology, 80 quadrates were set up and 80 soil samples were collected from QiLiYu. of Huoshan Mountain. By calculating the importance value and measurement the soil physical and chemical properfies ( soil pH, contents of soil water, contents of organic, N, P, K, etc. ), matrix of quadrates × species and matrix of quadrates × environmental factors were established. PlFls were defined according to CCA ordination. The results showed that: With changes of elevation and other environmental factors, HuoMountainQiliyu secondary forest can be divided into:Fl Carya cathayensis Sarg., Ostryopsis davidiana Decaisne, Carex lanceolata Boott. ; F2 Pinus tabulaeformis Carr. , Quercus wutaishanica Blume, Spiraea trilobata Linn, Arthraxon hispidus ( Thunb. ) Makio.; F3 Quercus wutaishanica Blume, Forsythia suspensa ( Thunb. ) Vahl. Eunm,, Carex lunceolata Boott. ;F4 Larix principis-rupprechtii Mayr. , Lespedeza formosa ( Vng. ) Koehne、Senecio nemorensis Linn;F5 Betula platyphylla

  5. A 22 570 yr record of vegetational and climatic change from Wenhai Lake in the Hengduan Mountains biodiversity hotspot, Yunnan, Southwest China

    Science.gov (United States)

    Yao, Y. F.; Song, X. Y.; Wortley, A. H.; Blackmore, S.; Li, C. S.

    2014-09-01

    The Hengduan Mountains, with their strong altitudinal vegetation zonation, form a biodiversity hotspot which offers the potential for comparison between sites in order to understand how this zonation arose and how it has responded to climate change and human impacts through time. This paper is one of the studies covering a range of altitudes within this hotspot, and presents a 22 570 yr pollen record of vegetational and climatic change based on a core 320 cm in depth collected from Wenhai Lake on the Jade Dragon Snow Mountain, one of the highest peaks in the Hengduan Mountains region of Yunnan, Southwest China. From 22 570 to 21 140 cal. yr BP, the vegetation was dominated by broad-leaved forest (comprising mainly Quercus, Betula and Castanopsis), accompanied by coniferous Pinus and Abies and the drought-tolerant herb Artemisia, indicating a cool and dry climate. In the period between 21 140 and 19 350 cal. yr BP, the vegetation was still dominated by broad-leaved forest but with a notable increase in pollen of aquatic plants, implying a relatively warm and moderately humid climate. The period 19 350 to 17 930 cal. yr BP was a transition stage from broad-leaved forest to needle-leaved forest, reflecting a warm-humid climate at the beginning and a cold-dry one at the end. Between 17 930 and 9250 cal. yr BP, needle-leaved forest and broad-leaved forest alternated in dominance in the early stages, with the former taking the predominant position by the end of the period, suggesting a climate fluctuating between warm-humid and cold-dry. From 9250 cal. yr BP to present, the vegetation has been dominated by needle-leaved forest (comprising mainly Pinus and Abies), coupled with broad-leaved forest (mainly Quercus and Betula), reflecting a transition in climatic conditions from warm-humid to cold-humid. During this period, human activity increased in this region, with impacts on the vegetation which may be evidenced by the distinct decrease in Pinus and Quercus pollen and

  6. Transformation of Carbon and Nitrogen by Earthworms in the Decomposition Processes of Broad-leaved Litters

    Institute of Scientific and Technical Information of China (English)

    DONG Weihua; YIN Xiuqin

    2007-01-01

    Earthworms are the important constituents in the decayed food web and the main ecological conditioners in the process of decomposition and nutrient mineralization. The transformation of organic carbon (C) and total nitrogen (N) in the broad-leaved litters ingested by earthworms was researched by means of a laboratory experiment. Experimental samples were collected from broad-leaved Korea Pine mixed forest in Liangshui National Natural Reserve (47°10'50"N, 128°53'20"E) in the northeastern Xiao Hinggan Mountains of Northeast China. The contents of organic C and total N in earthworms, leaf litters and earthworm faeces were analyzed. Results show that the organic C content was in the following order: leaf litters>faeces>earthworms, while total N content was contrary to that of the organic C. The organic C contents in the different leaf litters were in the following order: Tilia amurensis>Betula costata>Acer mono, whereas the total N contents in the different leaf litters were: Betula costata>Tilia amurensis>Acer mono. The contents of organic C and total N in the faeces from the different leaf litters were almost consistent with the contents of the leaf litters. After the leaf litters were ingested by earthworms, the organic C, which was transformed to increase earthworms' weights, accounted for 3.90%-13.31% of the total ingestion by earthworms, while that in the earthworm faeces accounted for 6.14%-13.70%. The transformed organic C through the other metabolism (e.g., respiration) of earthworms accounted for 75.04%-89.92%. The ingested organic C by earthworms was mostly used for metabolic activities. The N ingested by earthworms was less than organic C. It is estimated that 37.08% of total N was transformed to increase the earthworm's weight, 19.97% into earthworm faeces and 47.86% for the consumption of the earthworm's activities. The earthworms not only increased the content of organic C and total N in the soil, but also decreased the values of C/N in

  7. СРАВНИТЕЛЬНАЯ ХАРАКТЕРИСТИКА БАКТЕРИЙ РОДА BACILLUS СЕМЕЙСТВА БЕРЁЗОВЫЕ (BETULACAEA) ПРИ КУЛЬТИВИРОВАНИИ НА ИСКУССТВЕННЫХ ПИТАТЕЛЬНЫХ СРЕДАХ

    OpenAIRE

    Бороздина, Ирина

    2011-01-01

    В ходе исследования проведена идентификация микроорганизмов рода Bacillus, высеянных с поверхности филлоплана растений семейства Берёзовые (Betulacaea) Берёзы повислой (Betula pendula), Берёзы белой (Betula alba), Ольхи мелкопильчатой (Alnus serrulata) на основании изучения морфологических, культуральных, тинкториальных, физиолого-биохимических свойств. Дана сравнительная характеристика биологических свойств Bac. laterosporus, Bac. mesentericus, Bac. mycoides, Bac. subtilis, Bac. cereus, Bac....

  8. Modelling tree biomasses in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Repola, J.

    2013-06-01

    Biomass equations for above- and below-ground tree components of Scots pine (Pinus sylvestris L), Norway spruce (Picea abies [L.] Karst) and birch (Betula pendula Roth and Betula pubescens Ehrh.) were compiled using empirical material from a total of 102 stands. These stands (44 Scots pine, 34 Norway spruce and 24 birch stands) were located mainly on mineral soil sites representing a large part of Finland. The biomass models were based on data measured from 1648 sample trees, comprising 908 pine, 613 spruce and 127 birch trees. Biomass equations were derived for the total above-ground biomass and for the individual tree components: stem wood, stem bark, living and dead branches, needles, stump, and roots, as dependent variables. Three multivariate models with different numbers of independent variables for above-ground biomass and one for below-ground biomass were constructed. Variables that are normally measured in forest inventories were used as independent variables. The simplest model formulations, multivariate models (1) were mainly based on tree diameter and height as independent variables. In more elaborated multivariate models, (2) and (3), additional commonly measured tree variables such as age, crown length, bark thickness and radial growth rate were added. Tree biomass modelling includes consecutive phases, which cause unreliability in the prediction of biomass. First, biomasses of sample trees should be determined reliably to decrease the statistical errors caused by sub-sampling. In this study, methods to improve the accuracy of stem biomass estimates of the sample trees were developed. In addition, the reliability of the method applied to estimate sample-tree crown biomass was tested, and no systematic error was detected. Second, the whole information content of data should be utilized in order to achieve reliable parameter estimates and applicable and flexible model structure. In the modelling approach, the basic assumption was that the biomasses of

  9. Extinct mountain goat ( Oreamnos harringtoni) in Southeastern Utah

    Science.gov (United States)

    Mead, Jim I.; Agenbroad, Larry D.; Phillips, Arthur M.; Middleton, Larry T.

    1987-05-01

    The extinct Harrington's mountain goat ( Oreamnos harringtoni Stock) is predominantly known from dry cave localities in the Grand Canyon, Arizona, in addition to two sites in the Great Basin, Nevada, and from San Josecito Cave, Nuevo Leon, Mexico. A dry shelter in Natural Bridges National Monument, on the central Colorado Plateau, southeastern Utah, preserves numerous remains of the extinct mountain goat in addition to pack rat middens. Remains from a 100-cm stratigraphic profile indicate that O. harringtoni lived on the plateau >39,800 yr B.P., the oldest directly dated find of extinct mountain goat. Plant macrofossils indicate that Engelmann's spruce ( Picea engelmannii), limber pine ( Pinus flexilis), rose ( Rosa cf. woodsii), and Douglas fir ( Pseudotsuga menziesii) grew during the late Pleistocene where a riparian and a pinyon-juniper ( Pinus edulis-Juniperus osteosperma) community now predominates; Douglas fir are found only in mesic, protected, north-facing areas. Limber pine, Douglas fir, bark, and grasses were the major dietary components in the dung. A springtime diet of birch ( Betula) is determined from pollen clumps in dung pellets.

  10. Classification of plant somatic embryos by computer vision.

    Science.gov (United States)

    Hämäläinen, J J; Kurtén, U; Kauppinen, V

    1993-01-01

    This article deals with the automation of the process of somatic embryogenesis for the propagation of plants. An important problem is the monitoring of the embryo production process in order to decide the time to start harvesting embryos for further processing. The classification algorithm development for somatic embryos of birch (Betula pendula Roth) showed that automated recognition of embryos at different developmental stages is possible. No globular stage embryos were classified to be heart or torpedo stage and no heart or torpedo stage embryos were classified to be at globular stage. Heart and torpedo stage embryos were classified into three developmental classes by a new index that describes the relation of embryo breadth to the length of the root. The probability of classifying a nonembryo as an embryo was less than 1%, and 14% of the object classified as embryos by a human expert were discarded by the algorithm. A computer vision system suitable for automated monitoring of samples from the bioreactor was constructed. PMID:18601243

  11. Photosynthetic limitation of several representative subalpine species in the Catalan Pyrenees in summer.

    Science.gov (United States)

    Fernàndez-Martínez, J; Fleck, I

    2016-07-01

    Information on the photosynthetic process and its limitations is essential in order to predict both the capacity of species to adapt to conditions associated with climate change and the likely changes in plant communities. Considering that high-mountain species are especially sensitive, three species representative of subalpine forests of the Central Catalan Pyrenees: mountain pine (Pinus uncinata Mill.), birch (Betula pendula Roth) and rhododendron (Rhododendron ferrugineum L.) were studied under conditions associated with climate change, such as low precipitation, elevated atmospheric [CO2 ] and high solar irradiation incident at Earth's surface, in order to detect any photosynthetic limitations. Short-term high [CO2 ] increased photosynthesis rates (A) and water use efficiency (WUE), especially in birch and mountain pine, whereas stomatal conductance (gs ) was not altered in either species. Birch showed photosynthesis limitation through stomatal closure related to low rainfall, which induced photoinhibition and early foliar senescence. Rhododendron was especially affected by high irradiance, showing early photosynthetic saturation in low light, highest chlorophyll content, lowest gas exchange rates and least photoprotection. Mountain pine had the highest A, photosynthetic capacity (Amax ) and light-saturated rates of net CO2 assimilation (Asat ), which were maintained under reduced precipitation. Furthermore, maximum quantum yield (Fv /Fm ), thermal energy dissipation, PRI and SIPI radiometric index, and ascorbate content indicated improved photoprotection with respect to the other two species. However, maximum velocity of carboxylation of RuBisco (Vcmax ) indicated that N availability would be the main photosynthetic limitation in this species. PMID:26833754

  12. Spatial variations of Pb in the vertical zone of the soil-plant system in the Changbai Mountain National Nature Reserve

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The characteristics of vertical and horizontal variations of lead element(Pb) in soil-plant system of vertical zone in Changbai Mountain National Nature Reserve(CNNR) were studied.The results showed that Pb concentrations in soils of vertical zone are all above 25 mg/kg,and the average Pb concentration of each soil zone negatively correlates its degree of variation,i.e.brown coniferous forest soil zone has the lowest average Pb concentration of four soil zones,and the highest horizontal variation; however,mountain soddy forest soil has the highest average Pb concentration,and the lowest horizontal variation; the average concentration of plant Pb of each plant zone is lower than the worldwide average level of Pb in plant( Clarke),respectively,and plant Pb content order is consistent with soil Pb content order,but their horizontal variations are different from those in soil zones,the variation of mountain tundra forest zone is highest,but Betula ermanii forest zone the lowest.Vertical variation of plant Pb is obviously higher than that in soils with variation coefficient of 89.76%; the enrichment capability of plant for Pb is depended on the plant types and the different organs of plant; parent material and parent rock,pH values,soil organic matter and soil particle fraction etc.are the main factors influencing variations of Pb content in soil-plant system of vertical zone in CNNR.

  13. The skin prick test – European standards

    Directory of Open Access Journals (Sweden)

    Heinzerling Lucie

    2013-02-01

    Full Text Available Abstract Skin prick testing is an essential test procedure to confirm sensitization in IgE-mediated allergic disease in subjects with rhinoconjunctivitis, asthma, urticaria, anapylaxis, atopic eczema and food and drug allergy. This manuscript reviews the available evidence including Medline and Embase searches, abstracts of international allergy meetings and position papers from the world allergy literature. The recommended method of prick testing includes the appropriate use of specific allergen extracts, positive and negative controls, interpretation of the tests after 15 – 20 minutes of application, with a positive result defined as a wheal ≥3 mm diameter. A standard prick test panel for Europe for inhalants is proposed and includes hazel (Corylus avellana, alder (Alnus incana, birch (Betula alba, plane (Platanus vulgaris, cypress (Cupressus sempervirens, grass mix (Poa pratensis, Dactilis glomerata, Lolium perenne, Phleum pratense, Festuca pratensis, Helictotrichon pretense, Olive (Olea europaea, mugwort (Artemisia vulgaris, ragweed (Ambrosia artemisiifolia, Alternaria alternata (tenuis, Cladosporium herbarum, Aspergillus fumigatus, Parietaria, cat, dog, Dermatophagoides pteronyssinus, Dermatophagoides farinae, and cockroach (Blatella germanica. Standardization of the skin test procedures and standard panels for different geographic locations are encouraged worldwide to permit better comparisons for diagnostic, clinical and research purposes.

  14. The rhizosphere and PAH amendment mediate impacts on functional and structural bacterial diversity in sandy peat soil

    Energy Technology Data Exchange (ETDEWEB)

    Yrjaelae, Kim, E-mail: kim.yrjala@helsinki.f [Department of Biological and Environmental Sciences, General Microbiology, University of Helsinki, P.O. Box 56, (Biocenter 1C), 00014 Helsinki (Finland); Keskinen, Anna-Kaisa; Akerman, Marja-Leena; Fortelius, Carola [METROPOLIA University of Applied Science, Vantaa (Finland); Sipilae, Timo P. [Department of Biological and Environmental Sciences, General Microbiology, University of Helsinki, P.O. Box 56, (Biocenter 1C), 00014 Helsinki (Finland)

    2010-05-15

    To reveal the degradation capacity of bacteria in PAH polluted soil and rhizosphere we combined bacterial extradiol ring-cleavage dioxygenase and 16S rRNA analysis in Betula pubescens rhizoremediation. Characterisation of the functional bacterial community by RFLP revealed novel environmental dioxygenases, and their putative hosts were studied by 16S rRNA amplification. Plant rhizosphere and PAH amendment effects were detected by the RFLP/T-RFLP analysis. Functional species richness increased in the birch rhizosphere and PAH amendment impacted the compositional diversity of the dioxygenases and the structural 16S rRNA community. A shift from an Acidobacteria and Verrucomicrobia dominated to an Alpha- and Betaproteobacteria dominated community structure was detected in polluted soil. Clone sequence analysis indicated catabolic significance of Burkholderia in PAH polluted soil. These results advance our understanding of rhizoremediation and unveil the extent of uncharacterized functional bacteria to benefit bioremediation by facilitating the development of the molecular tool box to monitor bacterial populations in biodegradation. - The bacterial community analysis using 16S rRNA and extradiol dioxygenase marker genes in rhizoremediation revealed both a rhizosphere and a PAH-pollution effect.

  15. Online Measurement of Real-Time Cytotoxic Responses Induced by Multi-Component Matrices, such as Natural Products, through Electric Cell-Substrate Impedance Sensing (ECIS).

    Science.gov (United States)

    Fallarero, Adyary; Batista-González, Ana E; Hiltunen, Anna K; Liimatainen, Jaana; Karonen, Maarit; Vuorela, Pia M

    2015-01-01

    Natural products are complex matrices of compounds that are prone to interfere with the label-dependent methods that are typically used for cytotoxicity screenings. Here, we developed a label-free Electric Cell-substrate Impedance Sensing (ECIS)-based cytotoxicity assay that can be applied in the assessment of the cytotoxicity of natural extracts. The conditions to measure the impedance using ECIS were first optimized in mice immortalized hypothalamic neurons GT1-7 cells. The performance of four natural extracts when tested using three conventional cytotoxicity assays in GT1-7 cells, was studied. Betula pendula (silver birch tree) was found to interfere with all of the cytotoxicity assays in which labels were applied. The silver birch extract was also proven to be cytotoxic and, thus, served as a proof-of-concept for the use of ECIS. The extract was fractionated and the ECIS method permitted the distinction of specific kinetic patterns of cytotoxicity on the fractions as well as the extract's pure constituents. This study offers evidence that ECIS is an excellent tool for real-time monitoring of the cytotoxicity of complex extracts that are difficult to work with using conventional (label-based) assays. Altogether, it offers a very suitable cytotoxicity-screening assay making the work with natural products less challenging within the drug discovery workflow. PMID:26569236

  16. Pollen-Associated Microbiome Correlates with Pollution Parameters and the Allergenicity of Pollen

    Science.gov (United States)

    Obersteiner, Andrea; Gilles, Stefanie; Frank, Ulrike; Beck, Isabelle; Häring, Franziska; Ernst, Dietrich; Rothballer, Michael; Hartmann, Anton; Traidl-Hoffmann, Claudia; Schmid, Michael

    2016-01-01

    Pollen allergies have been rapidly increasing over the last decades. Many allergenic proteins and non-allergenic adjuvant compounds of pollen are involved in the plant defense against environmental or microbial stress. The first aim of this study was to analyze and compare the colonizing microbes on allergenic pollen. The second aim was to investigate detectable correlations between pollen microbiota and parameters of air pollution or pollen allergenicity. To reach these aims, bacterial and fungal DNA was isolated from pollen samples of timothy grass (Phleum pratense, n = 20) and birch trees (Betula pendula, n = 55). With this isolated DNA, a terminal restriction fragment length polymorphism analysis was performed. One result was that the microbial diversity on birch tree and timothy grass pollen samples (Shannon/Simpson diversity indices) was partly significantly correlated to allergenicity parameters (Bet v 1/Phl p 5, pollen-associated lipid mediators). Furthermore, the microbial diversity on birch pollen samples was correlated to on-site air pollution (nitrogen dioxide (NO2), ammonia (NH3), and ozone (O3)). What is more, a significant negative correlation was observed between the microbial diversity on birch pollen and the measured NO2 concentrations on the corresponding trees. Our results showed that the microbial composition of pollen was correlated to environmental exposure parameters alongside with a differential expression of allergen and pollen-associated lipid mediators. This might translate into altered allergenicity of pollen due to environmental and microbial stress. PMID:26910418

  17. Environmental niche and distribution of six deciduous tree species in the Spanish Atlantic region

    Directory of Open Access Journals (Sweden)

    Roces-Díaz JV

    2015-04-01

    Full Text Available Understanding the influence of environmental factors on the distribution of tree species is essential for developing management actions at regional level. We computed species distribution models for six European tree species to determine their potential niche in the Spanish Atlantic region, where deciduous forests are relatively well preserved. We used data from the national Forest Inventory and topo-climatic and soil variables to construct distribution models by the Generalized Linear Model procedure. The main factors found to determine the presence of the selected species were minimum winter temperature and mineral fertility of soils. Suitable habitats for Quercus petraea and F. sylvatica were mainly high-altitude areas with low minimum temperatures. In contrast, Q. robur and C. sativa were restricted to low altitudes and warmer conditions. Betula pubescens was not influenced by the elevation, probably because it is adapted to Atlantic conditions, and distribution of this species was associated with low fertility soils. Although the submediterranean Q. pyrenaica was positively influenced by the slope, model performance was poor for this species, possibly because of the truncated environmental range of the species in the study area. The findings suggest that temperature rather than moisture is shaping the distribution of deciduous trees at the southern limit of the Atlantic biogeographic region. We also note that the strong elevational difference between the warm coast and the cold mountains may determine the geographical disjunction between Q. robur and Q. petraea in southern Europe.

  18. Research observation: Hydrolyzable and condensed tannins in plants of northwest Spain forests

    Science.gov (United States)

    Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, E.E.

    2003-01-01

    Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

  19. Research observation: Hydrolyzable and condensed tannins in plants of the northwest

    Science.gov (United States)

    Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, Edward E.

    2003-01-01

    Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

  20. Depositional environments of the Hart coal zone (Paleocene), Willow Bunch Coalfield, southern Saskatchewan, Canada from petrographic, palynological, paleobotanical, mineral and trace element studies

    Energy Technology Data Exchange (ETDEWEB)

    Potter, J.; Beaton, A.P.; McDougall, W.J.; Nambudiri, E.M.V.; Vigrass, L.W. (University of Regina, SK (Canada). Energy Research Unit)

    1991-12-01

    Coal petrology, palynology, paleobotany and mineralogy of the Hart coal indicate deposition under wet, warm-temperate to subtropical climatic conditions in low-lying backswamps with fluvial channels and locally ponded areas. The coal is dominated by mixed xylitic/attrital lithotypes and by huminite macerals with secondary inertinite macerals and minor liptinite macerals. Good correlation exists between lithotypes and maceral composition. Local and vertical variations in proportions of huminites and inertinites reflect frequent fluctuations in water levels, periodic flooding, desiccation and burning of the peat. Swamps were dominated by {ital Glyptostrobus-Taxodium} forest with {ital Betula-Myrica-Alnus} communities and, locally {ital Laevigatosporites}, which are the dominant contributors to the xylite-rich lithotypes. Attrital lithotypes with abundant {ital Pandanus}, {ital Typha} and {ital Azolla} are consistent with wetter areas of a fluvial environment, including ponds and channels. Trace elements Cr, Cu, Mo, Ni, Si, Ti, U, Se, V, W, K and Th, typically associated with syngenetic minerals kaolinite, calcite and quartz, may have a volcanic source. High concentrations of Na, Ba and Ca found in organic complexes are of secondary origin and probably originate in deep source brines rather than marine surface waters. 55 refs., 11 figs., 5 tabs.

  1. Take me to your leader: does early successional nonhost vegetation spatially inhibit Pissodes strobi (Coleoptera: Curculionidae)?

    Science.gov (United States)

    Koopmans, Jordan M; De La Giroday, Honey-Marie C; Lindgren, B Staffan; Aukema, Brian H

    2009-08-01

    The spatial influences of host and nonhost trees and shrubs on the colonization patterns of white pine weevil Pissodes strobi (Peck) were studied within a stand of planted interior hybrid spruce [Picea glauca (Moench) Voss x Picea engelmannii (Parry) ex Engelm.]. Planted spruce accounted for one third of all trees within the stand, whereas the remaining two thirds were comprised of early-successional nonhost vegetation, such as alder (Alnus spp.), paper birch (Betula papyrifera Marsh.), black cottonwood [Populus balsamifera ssp. trichocarpa (T. Ng.) Brayshaw], lodgepole pine [Pinus contorta (Dougl.) ex Loud.], trembling aspen (Populus tremuloides Michx), willow (Salix spp.), and Canadian buffaloberry [Shepherdia canadensis (L.) Nutt.]. Unlike the spruce trees, nonhost vegetation in the stand was not uniformly distributed. Spatial point process models showed that Canadian buffaloberry, paper birch, black cottonwoood, and trembling aspen had negative associations with damage caused by the weevil, even though the density of the insects' hosts in these areas did not change. Moreover, knowing the locations of these nonhost trees provided as much, or more, inference about the locations of weevil-attacked trees as knowing the locations of suitable or preferred host trees (i.e., those larger in size). Nonhost volatiles, the alteration of soil composition, and overstory shade are discussed as potential explanatory factors for the patterns observed. New research avenues are suggested to determine whether nonhost vegetation in early successional stands might be an additional tool in the management of these insects in commercially important forests. PMID:19689899

  2. Origin of monoterpene emissions from boreal tree species: Determination of de novo and pool emissions by 13CO2 labeling

    Science.gov (United States)

    Rinne, J.; Ghirardo, A.; Koch, K.; Taipale, R.; Zimmer, I.; Schnitzler, J.

    2009-12-01

    Boreal forests emit a large amount of monoterpenes into the atmosphere. Traditionally these emissions are assumed to originate as evaporation from large storage pools. Thus their diurnal cycle would depend mostly on temperature. However, there is indication that a significant part of the monoterpene emission would originate directly from de novo synthesis. By applying 13CO2 fumigation and analyzing the isotope fractions with proton transfer reaction mass spectrometry (PTR-MS) and classical GC-MS we studied the origin of monoterpene emissions from some major Eurasian boreal and alpine tree species. We determined the fractions originating from de novo biosynthesis and from large internal monoterpene storages for three coniferous tree species with specialized monoterpene storage structures and one dicotyledon species without such structures. The emission from dicotyledon species Betula pendula originated solely from the de novo synthesis. The origin of the emissions from coniferous species was mixed with varying fraction originating from de novo synthesis (Pinus sylvestris 58%, Picea abies 33.5%, Larix decidua 9.8%) and the rest from large internal monoterpene storage pools. Application of the observed fractions of emission originating from de novo synthesis and large storage pools in a hybrid emission algorithm resulted in a better description of ecosystem scale monoterpene emissions from a boreal Scots pine forest stand.

  3. Direct amplification of DNA from fresh and preserved ectomycorrhizal root tips.

    Science.gov (United States)

    Bent, Elizabeth; Taylor, D Lee

    2010-02-01

    Methods are described by which DNA can be amplified directly from ectomycorrhizal root tip homogenates of a variety of plant species (Picea mariana (black spruce), Betula papyrifera (paper birch), Populus tremuloides (trembling aspen) and Alnus sp.(alder)), including root tips that have been preserved in RNA Later (Ambion, Austin, TX). In most cases for extracts and homogenates diluted 10-fold prior to PCR, and in all cases for 100-fold dilutions, direct amplification of DNA from fresh root tip homogenates yielded as many or more ng of PCR amplicon (fungal ITS region) than amplification of DNA extracted from the same tips using a commercial kit or a manual ethanol precipitation-based method. For alder root tip extracts diluted 10-fold, the commercial kit method yielded more ng of PCR amplicon than 10-fold diluted, although direct use of homogenates still resulted in amplification in all tips tested. We also demonstrate consistent amplification of DNA from homogenates of birch, spruce and aspen ectomycorrhizal root tips preserved for 4months in RNA Later. PMID:19963016

  4. Icelandic Birch Polyploids—The Case of a Perfect Fit in Genome Size

    Directory of Open Access Journals (Sweden)

    K. Anamthawat-Jónsson

    2010-01-01

    Full Text Available Two birch species coexist in Iceland, dwarf birch Betula nana and tree birch B. pubescens. Both species are variable morphologically, which has been shown to be due to introgressive hybridization via interspecific hybrids. The aim of this study was to examine if the introgression could be related to genome size. We characterized 42 plants from Bifröst woodland morphologically and cytogenetically. The population consisted of diploid B. nana (38%, tetraploid B. pubescens (55%, and triploid hybrids (7%. Genome size was measured from 12 plants, using Feulgen DNA image densitometry (FDM on spring leaf buds and flow cytometry (FCM with dormant winter twigs. The use of winter twigs for FCM is novel. The average 1C-values for diploid, triploid, and tetraploid plants were 448, 666, and 882 Mbp, respectively. Monoploid genome sizes were found to be statistically constant among ploidy levels. This stability is in contrast to the different taxonomic positions of the di- and tetraploids and also contrasts with the frequent occurrence of genome downsizing in polyploids.

  5. Arctic Shrub Growth Response to Climate Variation and Infrastructure Development on the North Slope of Alaska

    Science.gov (United States)

    Ackerman, D.; Finlay, J. C.; Griffin, D.

    2015-12-01

    Woody shrub growth in the arctic tundra is increasing on a circumpolar scale. Shrub expansion alters land-atmosphere carbon fluxes, nutrient cycling, and habitat structure. Despite these ecosystem effects, the drivers of shrub expansion have not been precisely established at the landscape scale. This project examined two proposed anthropogenic drivers: global climate change and local infrastructure development, a press disturbance that generates high levels of dust deposition. Effects of global change were studied using dendrochronology to establish a relationship between climate and annual growth in Betula and Salix shrubs growing in the Alaskan low Arctic. To understand the spatial heterogeneity of shrub expansion, this analysis was replicated in shrub populations across levels of landscape properties including soil moisture and substrate age. Effects of dust deposition on normalized difference vegetation index (NDVI) and photosynthetic rate were measured on transects up to 625 meters from the Dalton Highway. Dust deposition rates decreased exponentially with distance from road, matching previous models of road dust deposition. NDVI tracked deposition rates closely, but photosynthetic rates were not strongly affected by deposition. These results suggest that dust deposition may locally bias remote sensing measurements such as NDVI, without altering internal physiological processes such as photosynthesis in arctic shrubs. Distinguishing between the effects of landscape properties, climate, and disturbance will improve our predictions of the biogeochemical feedbacks of arctic shrub expansion, with potential application in climate change modeling.

  6. Vaccination for birch pollen allergy. Induction of affinity-matured or blocking IgG antibodies does not account for the reduced binding of IgE to Bet v 1

    DEFF Research Database (Denmark)

    Svenson, Morten; Jacobi, Henrik H; Bødtger, Uffe; Poulsen, Lars K; Rieneck, Klaus; Bendtzen, Klaus

    2003-01-01

    (Betula verrucosa) (Bet v 1), the major allergen in birch pollen, to serum IgG and IgE, separately and in competition. Sera from six birch pollen-allergic patients were obtained before and after 5 years of SAV, and binding was assessed with 125I-Bet v 1. Before SAV, IgG bound more than eight times the...... amount of Bet v 1 compared with IgE, and together they accounted for more than 85% of the serum binding capacity. While SAV induced minimal changes in IgE binding, the IgG binding capacities increased 6-32 times. In contrast, the binding avidities (K(d) 28-40pM) changed less than 20%, pre- and post......-SAV IgG provided similar inhibition of Bet v 1 binding to IgE at equimolar levels, and cross inhibition studies between IgG and IgE showed low inter-individual differences. Following SAV, all sera reduced Bet v 1 binding to CD23(+) cells, correlating with reduced binding of Bet v 1 to IgE (P...

  7. Bioconversion of Birch Wood Hemicellulose Hydrolyzate to Xylitol.

    Science.gov (United States)

    Miura, Masahiro; Shimotori, Yasutaka; Nakatani, Hisayuki; Harada, Akira; Aoyama, Masakazu

    2015-06-01

    A sugar solution containing 42.9 g l(-1) of xylose was prepared from the wood of Japanese white birch (Betula platyphylla var. japonica) by hydrolysis with 3 % sulfuric acid with a liquor-to-solid ratio of 4 (g g(-1)) at 120 °C for 1 h. During the acid hydrolysis, undesirable by-products were generated, such as acetic acid, furfural, and low-molecular-weight phenols, which inhibit bioconversion of xylose to xylitol. These inhibitors were successfully removed from the hydrolyzate by sorption onto a steam-activated charcoal followed by treatment with an anion exchange resin. Bioconversion of the detoxified hydrolyzate to xylitol by the yeast Candida magnoliae was investigated under the microaerobic conditions. The oxygen transfer rate (OTR) varied from 9.6 to 22.3 mmol O2 l(-1) h(-1). The best fermentative performance of C. magnoliae in the birch wood hydrolyzate (xylitol yield 0.74 g xylitol g xylose(-1); volumetric productivity 1.0 g l(-1) h(-1)) was obtained at the OTR of 12.6 mmol O2 l(-1) h(-1). PMID:25894947

  8. Comparative study of lipophilic extractives of hardwoods and corresponding ECF bleached kraft pulps

    Directory of Open Access Journals (Sweden)

    Pascoal Neto, C.

    2006-07-01

    Full Text Available The lipophilic extractives of Eucalyptus globulus , Eucalyptus grandis , Eucalyptus urograndis , Betula verrucosa and Acacia mangium woods and of the corresponding ECF bleached kraft pulps, were characterised by GC-MS. The five hardwoods showed significant differences in the content and composition of the main families of extractives, namely fatty acids, long chain aliphatic alcohols and sterols. Significant differences in the composition persist after wood pulping and ECF bleaching of pulps. The fate of the various types of extractives during the wood and pulp processing is discussed. Long chain aliphatic acids and alcohols are quite stable during the pulp production and are retained to a great extent in the final bleached pulp; delta 5 sterols are mostly oxidised and partially retained in the pulps, while delta 7 sterols are completely degraded and/or dissolved. B. verrucosa and A. mangium bleached pulps show contents of fatty acids about 4 and 20 times higher than that of Eucalyptus pulps, respectively, while the content of long chain aliphatic alcohols in A. mangium pulp is of the order of 100 times higher than Eucalyptus and B. verrucosa pulps.

  9. Establishment of trees on mixtures of pulverised fuel ash and gypsum. Part II: nutrition and trace elements

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, P.J.A.; Moffat, A.J.

    1993-10-01

    Pulverised fuel ash (PFA) sites in Britain have traditionally been restored to agriculture, but with the current trend to taking agricultural land out of production there is renewed interest in alternative end uses such as forestry. PFA has been shown to be colonized naturally to trees after 20-plus-years. In a series of experiments, the authors tested the growth and chemical uptake of a variety of tree species ([ital Populus nigra] var 'Italica', [ital P.alba], [ital Pinus nigra] var maritima, [ital Betula pendula], [ital Acer pseudoplatanus], [ital Alnus glutinosa], [ital A. cordata], and [ital Robinia pseudoacacia]) in a variety of mixtures (PFA, flue gas desulphurization gypsum, a 1:1 PFA:gypsum mix and a 2:1 mix, and a compost control). In earlier research several of the species were shown to tolerate the unusual physical and chemical characteristics of the mixtures. Here, elemental content of leaves from the trees after one year indicated that PFA consistently increased foliar levels of K, B, and Mo. Poor performance of some of the tree species in pure PFA was attributed to boron toxicity. Adding gypsum with the PFA tended to reduce B uptake. Fertilizers tended to improve tree performance. The authors were encouraged by the performance of the nitrogen fixing species ([ital Alnus] and [ital Robinia]), indicating that it may be possible to establish a self-sustaining woodland on power plant wastes.

  10. Diet and nutrient balance of red panda in Nepal

    Science.gov (United States)

    Panthi, Saroj; Coogan, Sean C. P.; Aryal, Achyut; Raubenheimer, David

    2015-10-01

    We identified the winter plant species consumed by red panda in the Dhorpatan Hunting Reserve of eastern Nepal and compared this to the early-summer diet which was determined previously by Panthi et al. (2012). In addition, we estimated the proximate nutritional content of the leaves identified in red panda diet for both seasons, and we used nutritional geometry to explore macronutrient balance of leaves from the two different sampling periods. We identified six different plants in winter scats, which were the same as found in the previously determined early-summer diet. Arundinaria spp. bamboos were the main species found (82.1 % relative frequency), followed by Acer spp. (6.3 %), Betula utilis (4.6 %), Quercus semicarpifolia (3.7 %), Berberis spp. (1.3 %), and lichens (1.0 %), leaving 2.0 % unidentified. Geometric analysis suggested that the macronutrient balance of seasonal diets were similar in nutrient balance to the most frequently consumed Arundinaria spp. Differences in macronutrient balance may indicate seasonal nutrient preferences, such as increased carbohydrate intake in winter for thermogenesis, and increased protein and lipid intake in early summer to support reproduction and lactation; however, these differences may also indicate differences in resource availability. Habitat conserved for red panda in the region should include sufficient Arundinaria spp. as well as lesser consumed plants which may serve as complimentary foods.

  11. Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

    Directory of Open Access Journals (Sweden)

    Guodong Jia

    Full Text Available Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined.

  12. Fungal Assemblages in Different Habitats in an Erman’s Birch Forest

    Science.gov (United States)

    Yang, Teng; Sun, Huaibo; Shen, Congcong; Chu, Haiyan

    2016-01-01

    Recent meta-analyses of fungal diversity using deeply sequenced marker genes suggest that most fungal taxa are locally distributed. However, little is known about the extent of overlap and niche partitions in total fungal communities or functional guilds within distinct habitats on a local forest scale. Here, we compared fungal communities in endosphere (leaf interior), phyllosphere (leaf interior and associated surface area) and soil samples from an Erman’s birch forest in Changbai Mountain, China. Community structures were significantly differentiated in terms of habitat, with soil having the highest fungal richness and phylogenetic diversity. Endophytic and phyllosphere fungi of Betula ermanii were more phylogenetically clustered compared with the corresponding soil fungi, indicating the ability of that host plants to filter and select their fungal partners. Furthermore, the majority of soil fungal taxa were soil specialists, while the dominant endosphere and phyllosphere taxa were aboveground generalists, with soil and plant foliage only sharing <8.2% fungal taxa. Most of the fungal taxa could be assigned to different functional guilds; however, the assigned guilds showed significant habitat specificity with variation in relative abundance. Collectively, the fungal assemblages in this Erman’s birch forest were strictly niche specialized and constrained by weak migration among habitats. The findings suggest that phylogenetic relatedness and functional guilds’ assignment can effectively interpret the certain ecological processes.

  13. Glacial Refugium of Pinus pumila (Pall.) Regel in Northeastern Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Shilo, N A; Lozhkin, A V; Anderson, P M; Brown, T A; Pakhomov, A Y; Solomatkina, T B

    2007-02-10

    One of the most glowing representatives of the Kolyma flora [1], ''Pinus pumila'' (Pall.) Regel (Japanese stone pine), is a typical shrub in larch forests of the northern Okhotsk region, basins of the Kolyma and Indigirka rivers, and high-shrub tundra of the Chukchi Peninsula. It also forms a pine belt in mountains above the forest boundary, which gives way to the grass-underbrush mountain tundra and bald mountains. In the southern Chukchi Peninsula, ''Pinus pumila'' along with ''Duschekia fruticosa'' (Rupr.) Pouzar and ''Betula middendorffii'' Trautv. et C. A. Mey form trailing forests transitional between tundra and taiga [2]. Pinus pumila pollen, usually predominating in subfossil spore-and-pollen spectra of northeastern Siberia, is found as single grains or a subordinate component (up 2-3%, rarely 10%) in spectra of lacustrine deposits formed during the last glacial stage (isotope stage 2) in the Preboreal and Boreal times of the Holocene. Sometimes, its content increases to 15-22% in spectra of lacustrine deposits synchronous to the last glacial stage near the northern coast of the Sea of Okhotsk [3], evidently indicating the proximity of Japanese stone pine thickets.

  14. Microclimate and Modeled Fire Behavior Differ Between Adjacent Forest Types in Northern Portugal

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    Anita Pinto

    2014-10-01

    Full Text Available Fire severity varies with forest composition and structure, reflecting micrometeorology and the fuel complex, but their respective influences are difficult to untangle from observation alone. We quantify the differences in fire weather between different forest types and the resulting differences in modeled fire behavior. Collection of in-stand weather data proceeded during two summer periods in three adjacent stands in northern Portugal, respectively Pinus pinaster (PP, Betula alba (BA, and Chamaecyparis lawsoniana (CL. Air temperature, relative humidity and wind speed varied respectively as CL < PP < BA, PP < CL < BA, and CL < BA < PP. Differences between PP and the other types were greatest during the warmest and driest hours of the day in a sequence of 10 days with high fire danger. Estimates of daytime moisture content of fine dead fuels and fire behavior characteristics for this period, respectively, from Behave and BehavePlus, indicate a CL < BA < PP gradient in fire potential. High stand density in CL and BA ensured lower wind speed and higher fuel moisture content than in PP, limiting the likelihood of an extreme fire environment. However, regression tree analysis revealed that the fire behavior distinction between the three forest types was primarily a function of the surface fuel complex, and more so during extreme fire weather conditions.

  15. β-Amyloid binding in elderly subjects with declining or stable episodic memory function measured with PET and [11C]AZD2184

    International Nuclear Information System (INIS)

    Cognitive decline has been suggested as an early marker for later onset of Alzheimer's disease. We therefore explored the relationship between decline in episodic memory and β-amyloid using positron emission tomography (PET) and [11C]AZD2184, a radioligand with potential to detect low levels of amyloid deposits. Healthy elderly subjects with declining (n = 10) or stable (n = 10) episodic memory over 15 years were recruited from the population-based Betula study and examined with PET. Brain radioactivity was measured after intravenous administration of [11C]AZD2184. The binding potential BPND was calculated using linear graphical analysis with the cerebellum as reference region. The binding of [11C]AZD2184 in total grey matter was generally low in the declining group, whereas some binding could be observed in the stable group. Mean BPND was significantly higher in the stable group compared to the declining group (p = 0.019). An observation was that the three subjects with the highest BPND were ApoE ε4 allele carriers. We conclude that cognitive decline in the general population does not seem to stand by itself as an early predictor for amyloid deposits. (orig.)

  16. The occurence of rare and protected plant species on the peat bog near Lake Bikcze (Łęczyńsko-Włodawskie Lakeland

    Directory of Open Access Journals (Sweden)

    Magdalena Pogorzelec

    2012-12-01

    Full Text Available This paper presents the results of a pilot field study, conducted in July 2007, designed to make floristic evaluation of the peat bog area adjacent to the western shore of Lake Bikcze (Łęczyńsko-Włodawskie Lakeland. The main aim of the study was to confirm the occurrence of populations of rare and legally protected plant species in this area and to identify, on a preliminary basis, habitat conditions in their stands. The occurrence of populations of the following strictly protected plant species: Betula humilis, Salix lapponum, Salix myrtilloides, Carex limosa, Drosera intermedia, Drosera rotundifolia, Dactylorhiza incarnata; and partially protected species: Menyanthes trifoliata, has been confirmed in the studied peat bog. Both an investigation of abiotic factors, conducted in situ, and an analysis of the species composition of the flora in terms of habitat preferences of particular groups of taxa have shown that the described rare plant species find suitable conditions for their growth and development in the studied peat bog.

  17. Determining the Composition of Lignins in Different Tissues of Silver Birch

    Science.gov (United States)

    Fagerstedt, Kurt V.; Saranpää, Pekka; Tapanila, Tarja; Immanen, Juha; Alonso Serra, Juan Antonio; Nieminen, Kaisa

    2015-01-01

    Quantitative and qualitative lignin analyses were carried out on material from the trunks of silver birch (Betula pendula Roth) trees. Two types of material were analyzed. First, whole birch trunk pieces were cryosectioned into cork cambium, non-conductive phloem, the cambial zone (conductive phloem, cambium and differentiating xylem), lignified xylem and the previous year’s xylem; material that would show differences in lignin amount and quality. Second, clonal material from one natural birch population was analyzed to show variations between individuals and between the lignin analysis methods. The different tissues showed marked differences in lignin amount and the syringyl:guaiacyl (S/G) ratio. In the non-conductive phloem tissue containing sclereids, the S/G ratio was very low, and typical for phloem fibers and in the newly-formed xylem, as well as in the previous year’s xylem, the ratio lay between five and seven, typical for broadleaf tree xylem. Clonal material consisting of 88 stems was used to calculate the S/G ratios from the thioacidolysis and CuO methods, which correlated positively with an R2 value of 0.43. Comparisons of the methods indicate clearly that the CuO method is a good alternative to study the monomeric composition and S/G ratio of wood lignins. PMID:27135322

  18. Belowground carbon pools and dynamics in China's warm temperate and sub-tropical deciduous forests

    Directory of Open Access Journals (Sweden)

    C. W. Xiao

    2009-07-01

    Full Text Available We report the first estimates of pools and dynamics of microbes, roots, plant litter and soil organic carbon (SOC in three dominant types of China's vast deciduous forest area: Betula platyphylla, Quercus liaotungensis, and Quercus aliena varacuteserrata. Organic matter degradation rates overshadowed litter inputs as the main determinant of the soil carbon stocks. Across the three forests, rates of litter decomposition were also indicative for turnover rates of SOC. Litter and SOC decay was faster in the sub-tropical than in the warm-temperate forests. Among the latter, SOC turnover was highest in the forest producing the higher-quality litter. Microbial biomass was, as expected, correlated with SOC content. Microbial activity, in contrast, was highest at the sub-tropical forest, despite the lower SOC availability, lower fraction of labile SOC, and lower soil microbial biomass. These results may contribute to increased understanding of controls over belowground carbon cycling in deciduous forests.

  19. НЕЛИНЕЙНЫЕ МОДЕЛИ ВЗАИМОСВЯЗИ РАСПРОСТРАНЕНИЯ INONOTUS OBLIQUUS (PERS.) PIL. С БОНИТЕТОМ И ВОЗРАСТОМ БЕРЕЗОВОГО ЛЕСА. ВЛИЯНИЕ РЯДА МОРФОЛОГИЧЕСКИХ ХАРАКТЕРИСТИК НАСАЖДЕНИЙ НА ВСТРЕЧАЕМОСТЬ БАЗИДИАЛЬНОГО МАКРОМИЦЕТА

    OpenAIRE

    Баландайкин, М.

    2013-01-01

    Показаны регрессии двух параметров таксации на пространственную организацию факультативного сапротрофа в насаждениях Betula pendula Roth. Рассмотрены особенности влияния некоторых биоэкологических факторов на миграцию гриба.

  20. РАСПРОСТРАНЕНИЕ МАКРОМИЦЕТА INONOTUS OBLIQUUS (PERS.) PIL. В БЕРЕЗОВЫХ НАСАЖДЕНИЯХ РАЗЛИЧНОГО ПРОИСХОЖДЕНИЯ

    OpenAIRE

    Баландайкин, М.

    2013-01-01

    Позиционируется элементарная березовая синузия автотрофно детерминируемой консорции, разобщенная в констелляции по сингулярному таксационному признаку (происхождение древостоя) в аспекте импактивности Betula pendula Roth. скошенным трутовиком.

  1. How much selenium do medicinal plants contain? Results of a research on wild-growing species from Western Romania

    Directory of Open Access Journals (Sweden)

    Diana Simona ANTAL

    2010-05-01

    Full Text Available The ultratrace element selenium is essential for higher animals and man. It is an active constituent of over twenty different selenoproteins from human tissues. As well, this rare nonmetal element is a potent anticarcinogen, inhibiting both chemically and virally induced tumors. The ever-increasing biological importance of Se determined us to perform the first largescale investigation of Romanian medicinal plants in what their Se content is concerned, and to evaluate the extraction ratio of this element during decoction. ICP-MS (Inductively Coupled Plasma - Mass Spectrometry analysis revealed average Se contents of 43 μg/kg dry matter. The highest Se content was found in aerial parts (average of 60 μg/kg, followed by leaves (58, roots (54, flowers (35 and fruits (12. Species grown on limestone weathering soils are significantly richer in Se than the ones grown on granite or phyllite. Outstanding Se contents were measured for samples of Betula pendula leaves – 381, 131 and 113 μg Se/kg, Agrimonia eupatoria herb - 332 μg/kg, and Galium verum herb – 287 μg/kg. The extraction ratio of Se through decoction ranges from 4% (valerian roots to 83% (chicory roots. The Se content and the high amounts of flavonoids in birch, agrimony and yellow bedstraw underline the value of these plants in the auxiliary treatment of various free-radical mediated diseases.

  2. Þéttleiki og fjölbreytileiki sveppróta í misgömlum birki og lerkiskógum

    OpenAIRE

    Brynja Hrafnkelsdóttir 1982

    2009-01-01

    Þéttleiki og fjölbreytileiki útrænnar svepprótar var rannsakaður í misgömlum birkiskógum (Betula pubescens) og lerkiskógum (Larix sibirica) á Fljótsdalshéraði, auk þess sem skóglaust mólendi var haft með til samanburðar. Leitað var svara við eftirfarandi spurningum: a) Er svepprótarsmit til staðar í skóglausu landi á Fljótsdalshéraði? b) Myndast svepprót á birkiplöntum ef þær eru gróðursettar í lerkiskóg? Myndast svepprót á lerkiplöntur ef þær eru gróðursettar í birkiskóg? c) Er hægt að no...

  3. Spatial heterogeneity in the timing of birch budburst in response to future climate warming in Ireland

    Science.gov (United States)

    Caffarra, Amelia; Zottele, Fabio; Gleeson, Emily; Donnelly, Alison

    2014-05-01

    In order to predict the impact of future climate warming on trees it is important to quantify the effect climate has on their development. Our understanding of the phenological response to environmental drivers has given rise to various mathematical models of the annual growth cycle of plants. These models simulate the timing of phenophases by quantifying the relationship between development and its triggers, typically temperature. In addition, other environmental variables have an important role in determining the timing of budburst. For example, photoperiod has been shown to have a strong influence on phenological events of a number of tree species, including Betula pubescens (birch). A recently developed model for birch (DORMPHOT), which integrates the effects of temperature and photoperiod on budburst, was applied to future temperature projections from a 19-member ensemble of regional climate simulations (on a 25 km grid) generated as part of the ENSEMBLES project, to simulate the timing of birch budburst in Ireland each year up to the end of the present century. Gridded temperature time series data from the climate simulations were used as input to the DORMPHOT model to simulate future budburst timing. The results showed an advancing trend in the timing of birch budburst over most regions in Ireland up to 2100. Interestingly, this trend appeared greater in the northeast of the country than in the southwest, where budburst is currently relatively early. These results could have implications for future forest planning, species distribution modeling, and the birch allergy season.

  4. Stem CO2 release under illumination: corticular photosynthesis, photorespiration or inhibition of mitochondrial respiration?

    Science.gov (United States)

    Wittmann, Christiane; Pfanz, Hardy; Loreto, Francesco; Centritto, Mauro; Pietrini, Fabrizio; Alessio, Giorgio

    2006-06-01

    In illuminated stems and branches, CO2 release is often reduced. Many light-triggered processes are thought to contribute to this reduction, namely photorespiration, corticular photosynthesis or even an inhibition of mitochondrial respiration. In this study, we investigated these processes with the objective to discriminate their influence to the overall reduction of branch CO2 release in the light. CO2 gas-exchange measurements of young birch (Betula pendula Roth.) branches (O2) and non-photorespiratory (exchange. This suppression of photorespiration was attributed to the high CO2 concentrations (C(i)) within the bark tissues (1544 +/- 227 and 618 +/- 43 micromol CO2 mol(-1) in the dark and in the light, respectively). Changes in xylem CO2 were not likely to explain the observed decrease in stem CO2 release as gas-exchange measurements before and after cutting of the branches did not effect CO2 efflux to the atmosphere. Combined fluorescence and gas-exchange measurements provided evidence that the light-dependent reduction in CO2 release can pre-dominantly be attributed to corticular refixation, whereas an inhibition of mitochondrial respiration in the light is unlikely to occur. Corticular photosynthesis was able to refix up to 97% of the CO2 produced by branch respiration, although it rarely led to a positive net photosynthetic rate. PMID:17080940

  5. The effect of u.v.-B radiation on u.v.-absorbing secondary metabolites in birch seedlings grown under simulated forest soil conditions

    International Nuclear Information System (INIS)

    Birch (Betula pendula Roth) seedlings were grown under enhanced u.v.-B radiation and simulated forest-soil conditions, after which individual secondary metabolites were determined in the leaves. It was found that not all of the u.v.-absorbing secondary metabolites of the seedlings responded to supplementary u.v.-B radiation. Under increased u.v.-B radiation, significant increases in concentration were observed only for the major flavonoid, quercitrin, the minor fiavonoid, myricetin-3-galactoside, and for chlorogenic acid. On the other hand, 3,4′dihydroxypropiophenone-3-β-D-glucopyranoside decreased under u.v.-B irradiation. The concentration of phenolic compounds in the leaves changed during the growing season (between two harvests) but this change was not related to u.v.-B enhancement. A low availability of mineral nutrients did not impair the capacity of the seedlings to accumulate u.v.-protecting phenolic compounds under increased u.v.-B radiation. The growth conditions used might have affected the intracellular concentrations of secondary metabolites, and thus furnished the birch seedlings with an increased tolerance of u.v.-B radiation. These findings point to the significance of certain phenolic components in the protection of deciduous trees against u.v.-B radiation. (author)

  6. Leaf surface lipophilic compounds as one of the factors of silver birch chemical defense against larvae of gypsy moth.

    Science.gov (United States)

    Martemyanov, Vyacheslav V; Pavlushin, Sergey V; Dubovskiy, Ivan M; Belousova, Irina A; Yushkova, Yuliya V; Morosov, Sergey V; Chernyak, Elena I; Glupov, Victor V

    2015-01-01

    Plant chemical defense against herbivores is a complex process which involves a number of secondary compounds. It is known that the concentration of leaf surface lipophilic compounds (SLCs), particularly those of flavonoid aglycones are increased with the defoliation treatment of silver birch Betula pendula. In this study we investigated how the alteration of SLCs concentration in the food affects the fitness and innate immunity of the gypsy moth Lymantria dispar. We found that a low SLCs concentrations in consumed leaves led to a rapid larval development and increased females' pupae weight (= fecundity) compared to larvae fed with leaves with high SLCs content. Inversely, increasing the compounds concentration in an artificial diet produced the reverse effects: decreases in both larval weight and larval survival. Low SLCs concentrations in tree leaves differently affected larval innate immunity parameters. For both sexes, total hemocytes count in the hemolymph increased, while the activity of plasma phenoloxidase decreased when larvae consume leaves with reduced content of SLCs. Our results clearly demonstrate that the concentration of SLCs in silver birch leaves affects not only gypsy moth fitness but also their innate immune status which might alter the potential resistance of insects against infections and/or parasitoids. PMID:25816371

  7. Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch

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    Chiang Vincent L

    2009-09-01

    Full Text Available Abstract Background The monolignol biosynthetic pathway interconnects with the biosynthesis of other secondary phenolic metabolites, such as cinnamic acid derivatives, flavonoids and condensed tannins. The objective of this study is to evaluate whether genetic modification of the monolignol pathway in silver birch (Betula pendula Roth. would alter the metabolism of these phenolic compounds and how such alterations, if exist, would affect the ectomycorrhizal symbiosis. Results Silver birch lines expressing quaking aspen (Populus tremuloides L. caffeate/5-hydroxyferulate O-methyltransferase (PtCOMT under the 35S cauliflower mosaic virus (CaMV promoter showed a reduction in the relative expression of a putative silver birch COMT (BpCOMT gene and, consequently, a decrease in the lignin syringyl/guaiacyl composition ratio. Alterations were also detected in concentrations of certain phenolic compounds. All PtCOMT silver birch lines produced normal ectomycorrhizas with the ectomycorrhizal fungus Paxillus involutus (Batsch: Fr., and the formation of symbiosis enhanced the growth of the transgenic plants. Conclusion The down-regulation of BpCOMT in the 35S-PtCOMT lines caused a reduction in the syringyl/guaiacyl ratio of lignin, but no significant effect was seen in the composition or quantity of phenolic compounds that would have been caused by the expression of PtCOMT under the 35S or UbB1 promoter. Moreover, the detected alterations in the composition of lignin and secondary phenolic compounds had no effect on the interaction between silver birch and P. involutus.

  8. Traditional Uses of Plants in the Tolfa–Cerite–Manziate Area (Central Italy

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    Paolo Maria Guarrera

    2015-09-01

    Full Text Available Traditional knowledge of local plant uses is rapidly fading away, especially in rural Mediterranean areas. We carried out ethnobotanical research in 2010-2011 in order to investigate the local knowledge of wild plants in the Tolfa–Cerite–Manziate area of Italy (Latium, district of Rome. We carried out a total of 45 semi-structured interviews with farmers, herders, and fishers. Here, a simple diachronic comparison is made between the current study and a previous one conducted in some of the villages of the study area to highlight potential losses of traditional knowledge of local plants. We documented a total of 102 plant species, belonging to 48 families, along with their uses (excluding food uses. We also reported some non-plant based remedies that were primarily used in veterinary medicine. Some plant uses, especially for making handicrafts, have not been reported previously (e.g., those of Celtis australis L. Cannabaceae, Betula pendula Roth Betulaceae. Many plant uses are no longer remembered in the area, which indicates a loss of local ethnobotanical knowledge.

  9. Diversity, Distribution Pattern and Conservation Status of the Plants Used in Liver Diseases/Ailments in Indian Himalayan Region

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In the Indian Himalayan Region, the studies focused on diversity of the plants used for treating liver diseases/ailments have not been carried out so far. Therefore, the present attempt has been made to study the diversity, distribution patternand conservation status of the plant species used for treating liver diseases/ailments in that region. A total of 138 species (35 species of trees, 22 shrubs and 81 herbs) belonging to 98 genera in 60 families have been recorded. Amongst the families, Euphorbiaceae (9 species), and altitudinal zone <1,800 m, (i.e., 115species) are rich in species. Traditionally, various plant parts, such as roots/rhizomes/tubers (46species), leaves (31), whole plants (30), barks (15),fruits (13), seeds and unspecified parts (8 each), and inflorescence (1) are used for the treatment of liver diseases/ailments. 34 species are native, 3 are endemic and 15 near endemic. 7 species are categorized as Critically Endangered (Betula utilis),Endangered (Podophyllum hexandrum, Ephedra gerardiana, and Nardostachys grandiflora) and Vulnerable (Bergenia ligulata, B. stracheyi, and Hedychium spicatum) using new IUCN criteria.Available chemical composition of plant parts used for the treatment of liver diseases/ailments have been given. Assessment of the populations of threatened species, development of an appropriate strategy,action plan for the conservation and sustainable utilization of such components of plant diversity are suggested.

  10. Can Urban Trees Reduce the Impact of Climate Change on Storm Runoff?

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    Katarina ZABRET

    2015-11-01

    Full Text Available The process of urbanisation leads to significant changes in surface cover, which influence the hydrological properties of an area. The infiltration of precipitation into the soil is reduced, so that both surface water runoff and the velocity at which water travels have increased drastically. In recent decades climate change has also been observed to affect precipitation trends. Many studies have shown that the amount of rainfall is increasing and that heavy rainfall events are becoming more frequent. These changes are producing more runoff, which has to be drained. Urban trees can reduce the amount of precipitation reaching the ground due to rainfall interception, and are becoming increasingly recognized as an effective means for the regulation of storm water volumes and costs. The study measured rainfall interception in an urban area. It shows that Betula pendula can intercept 20.6% of annual rainfall, whereas Pinus nigra could intercept as much as 51.0% of annual rainfall. The advantage of rainfall interception was shown in the case of a parking lot where the planting of trees was able to reduce runoff by up to 17%.

  11. Large ontogenetic declines in intra-crown leaf area index in two temperate deciduous tree species.

    Science.gov (United States)

    Nock, C A; Caspersen, J P; Thomas, S C

    2008-03-01

    The widespread occurrence of age-related changes in leaf morphology and allocation suggests that the leaf area index of individual trees (intra-crown LAI) may decline late in ontogeny. We used direct, within-canopy measurements to quantify the LAI of canopy trees with exposed crowns of two temperate deciduous species. Intra-crown LAI declined from approximately 7 to 4 in Acer saccharum, and from approximately 9.5 to 6.5 in Betula alleghaniensis, as tree size increased (from 15 to 72 cm diameter at breast height [dbh]). For A. saccharum, age (which varied from 30 to 160 years) was a significantly better predictor of LAI decline than dbh. We also modeled the effect of ontogenetic declines in LAI on understory light availability and found that light transmission increases significantly as canopy trees grow and mature. Our results thus suggest that gradual declines in LAI with tree age may play an important and overlooked role in contributing to the heterogeneity of sub-canopy light regimes in mature forests. PMID:18459337

  12. Canopy carbon net assimilation of an urban, naturally assembled brownfield forest

    Science.gov (United States)

    Schafer, K. V.; Wadhwa, S.; Tripathee, R.; Gallagher, F. J.

    2010-12-01

    In this study, we have been investigating an urban brownfield at Liberty State Park that has been abandoned approximately for 40 years. Natural colonization has taken place that allowed a pioneer forest to grow with primarily Betula populifera and Populus spec. Despite soil metal contamination this urban forest exhibits moderate annual productivity and serves as a carbon sink. Diameters at breast height (DBH, 1.35 m above ground) of all trees in a study plot were measured. Aboveground biomass equations were determined for both species through destructive sampling. Aboveground net primary production was about 770 gC m-2 a-1 in 2009. Canopy net assimilation (AnC) was modeled with the canopy conductance constrained assimilation (4CA) model using measured sapflux derived conductance and photosynthetic parameters measured with a LICOR 6400. Annual AnC in 2009 was approximately 1500 gC m-2 a-1 thus with a partitioning of biomass and respiration in the same range of most natural forest with less anthropogenic induced stress. Urban brownfields thus can serve as C sinks and provide phytostabilization of contaminants.

  13. Treeline dynamics with climate change at the central Nepal Himalaya

    Science.gov (United States)

    Gaire, N. P.; Koirala, M.; Bhuju, D. R.; Borgaonkar, H. P.

    2014-07-01

    Treeline shifting in tandem with climate change has widely been reported from various parts of the world. In Nepal, several impacts of climate change on the physical environment have been observed, but study on the biological impacts is lacking. This dendrochronological study was carried out at the treeline in the high mountain slope of Kalchuman Lake (3750-4003 m a.s.l.) area of Manaslu Conservation Area in the central Nepal Himalaya to explore the impact of climate change on the treeline dynamic. Two belt transect plots (size: 20 m wide, > 250 m long) were laid which included treeline as well as tree species limit. Ecological mapping of all individuals of dominant trees Abies spectabilis and Betula utilis was done and their tree cores were collected. Stand character and age distribution revealed an occurrence of more matured B. utilis (max. age 198 years) compared to A. spectabilis (max. age 160 years). A. spectabilis contained an overwhelmingly high population (89%) of younger plants (climate change with differential pattern in regeneration condition, much wider differences are anticipated in their population status as climate continues to change throughout the century.

  14. Wood surface roughness: an impact of wood species, grain direction and grit size

    Directory of Open Access Journals (Sweden)

    Justina Vitosytė

    2015-06-01

    Full Text Available For the research the samples of ash (Fraxinus excelsior L., birch (Betula L., black alder (Alnus glutinosa L., Scots pine (Pinus Sylvestris L. and spruce (Picea abies L. wood were used with dimensions of 270×215×15 mm. All wood samples were tangentially planed, defect free and kiln dried. Before the research, the average moisture content, wood density, number of annual rings per 1 cm, average width of annual ring and wood surface grain direction were evaluated. Different wood surface roughness of the samples was obtained sanding wood samples in the eccentric sanding stand, using standard open-type sandpaper with different grit size. The arithmetic mean value of the single roughness depths of consecutive sampling lengths parameter Rz of the sanded wood samples were measured in five sectors along the wood grain, across and in the angle of 45°, using a contact stylus profilometer. In total 1800 measurements were done during testing series. Obtained measurement results were processed by digital Gaussian filter according to DIN EN ISO 11562. In the research the dependence of wood surface on wood species, grain direction and grit size of abrasive material was evaluated.DOI: http://dx.doi.org/10.5755/j01.ms.21.2.5882

  15. Unified phenology model with Bayesian calibration for several European species in Belgium

    Science.gov (United States)

    Fu, Y. S. H.; Demarée, G.; Hamdi, R.; Deckmyn, A.; Deckmyn, G.; Janssens, I. A.

    2009-04-01

    Plant phenology is a good bio-indicator for climate change, and this has brought a significant increase of interest. Many kinds of phenology models have been developed to analyze and predict the phenological response to climate change, and those models have been summarized into one kind of unified model, which could be applied to different species and environments. In our study, we selected seven European woody plant species (Betula verrucosa, Quercus robur pedunculata, Fagus sylvatica, Fraxinus excelsior, Symphoricarpus racemosus, Aesculus hippocastanum, Robinia pseudoacacia) occurring in five sites distributed across Belgium. For those sites and tree species, phenological observations such as bud burst were available for the period 1956 - 2002. We also obtained regional downscaled climatic data for each of these sites, and combined both data sets to test the unified model. We used a Bayesian approach to generate distributions of model parameters from the observation data. In this poster presentation, we compare parameter distributions between different species and between different sites for individual species. The results of the unified model show a good agreement with the observations, except for Fagus sylvatica. The failure to reproduce the bud burst data for Fagus sylvatica suggest that the other factors not included in the unified model affect the phenology of this species. The parameter series show differences among species as we expected. However, they also differed strongly for the same species among sites.Further work should elucidate the mechanism that explains why model parameters differ among species and sites.

  16. Assessment of the urban trees health status on the base of nutrient and pigment content in their leaves

    Directory of Open Access Journals (Sweden)

    SLAVEYA PETROVA

    2014-04-01

    Full Text Available Town settlements have different load level by emissions originated mostly from transport, industry and heating system. Their environmental and climate conditions are more or less changed that effect to growth, physiology and vigor of woody plants at the city public vegetation areas. Our study on determining the impact of urban environment on the tree health status was focused on the quantities of nutrients and main components of the pigment complex – chlorophyll a, chlorophyll b and carotenoids. Leaves of Acer platanoides L., Aesculus hippocastanum L. and Betula pendula Roth. were sampled from urban areas with different type of anthropogenic pressure in the town of Plovdiv (Bulgaria. Concentrations of the elements Ca, K, Mg, N, Na, P, and S were analyzed by ICP-MS. Health condition of trees in the city parks and suburban areas was acceptable, but in the central part and close to the industrial area it was non-satisfactory. This preliminary research pointed ecophysiological tools as useful to develop new criteria for sustainable urban arboriculture, including species selection (based on stress tolerance criteria, nursery hardening and preconditioning, and care after planting.

  17. Replacing monocultures with mixed-species stands: Ecosystem service implications of two production forest alternatives in Sweden.

    Science.gov (United States)

    Felton, Adam; Nilsson, Urban; Sonesson, Johan; Felton, Annika M; Roberge, Jean-Michel; Ranius, Thomas; Ahlström, Martin; Bergh, Johan; Björkman, Christer; Boberg, Johanna; Drössler, Lars; Fahlvik, Nils; Gong, Peichen; Holmström, Emma; Keskitalo, E Carina H; Klapwijk, Maartje J; Laudon, Hjalmar; Lundmark, Tomas; Niklasson, Mats; Nordin, Annika; Pettersson, Maria; Stenlid, Jan; Sténs, Anna; Wallertz, Kristina

    2016-02-01

    Whereas there is evidence that mixed-species approaches to production forestry in general can provide positive outcomes relative to monocultures, it is less clear to what extent multiple benefits can be derived from specific mixed-species alternatives. To provide such insights requires evaluations of an encompassing suite of ecosystem services, biodiversity, and forest management considerations provided by specific mixtures and monocultures within a region. Here, we conduct such an assessment in Sweden by contrasting even-aged Norway spruce (Picea abies)-dominated stands, with mixed-species stands of spruce and birch (Betula pendula or B. pubescens), or spruce and Scots pine (Pinus sylvestris). By synthesizing the available evidence, we identify positive outcomes from mixtures including increased biodiversity, water quality, esthetic and recreational values, as well as reduced stand vulnerability to pest and pathogen damage. However, some uncertainties and risks were projected to increase, highlighting the importance of conducting comprehensive interdisciplinary evaluations when assessing the pros and cons of mixtures. PMID:26744048

  18. The likely impact of climate change on the biodiversity of Italian forests

    Directory of Open Access Journals (Sweden)

    Borghetti M

    2012-12-01

    Full Text Available Based on literature results and our expert evaluation, we report some likely impacts of climate change on the biodiversity of forest communities in Italy by the end of this century. In the Mediterranean region and on the Apennines: at low altitudes, vulnerability of Pinus sp. and Quercus ilex forests, with loss of intraspecific genetic variability; transition from Mediterranean closed-canopy macchia to scattered shrublands; risk of local extinction for coastal populations of mesic/relic hardwood species (e.g., Quercus robur, Carpinus betulus, Zelkova sicula, Fraxinus sp.; ’eastern’ relic species like Quercus troiana, Quercus frainetto, Quercus aegilops, and Q. gussonei in Sicily, and the peripheral low-altitude Fagus sylvatica populations, will be highly vulnerable; in the mid-altitude forest, vulnerability of most demanding species like Quercus cerris and Castanea sativa, possible immigration of Mediterranean species like Quercus ilex; in the montane forest, Fagus sylvatica and Abies alba will be less competitive with respect to more continental and drought-resistant tree species, and could loose genetic variability; relic species like Taxus baccata and Betula aetnensis may be at risk. In the alpine region: upward movement of timberline and changes in timberline communities, for instance Picea abies may be more competitive over Larix decidua, and fragmented species like Pinus cembra might become vulnerable. In general, we recognize the difficulty in separating the effects of climatic variables from those of other processes, like fires and land-use change.

  19. β-Amyloid binding in elderly subjects with declining or stable episodic memory function measured with PET and [{sup 11}C]AZD2184

    Energy Technology Data Exchange (ETDEWEB)

    Mattsson, Patrik [Karolinska Institutet, Centre for Psychiatry Research, Department of Clinical Neuroscience, Stockholm (Sweden); Karolinska University Hospital, Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatry Research, Stockholm (Sweden); Forsberg, Anton; Halldin, Christer [Karolinska Institutet, Centre for Psychiatry Research, Department of Clinical Neuroscience, Stockholm (Sweden); Persson, Jonas; Nilsson, Lars-Goeran [Karolinska Institute and Stockholm University, Aging Research Center (ARC), Stockholm (Sweden); Nyberg, Lars [Umeaa University, Department of Radiation Sciences (Diagnostic Radiology), Umeaa (Sweden); Farde, Lars [Karolinska Institutet, Centre for Psychiatry Research, Department of Clinical Neuroscience, Stockholm (Sweden); AstraZeneca Translational Science Center at Karolinska Institutet, Stockholm (Sweden)

    2015-09-15

    Cognitive decline has been suggested as an early marker for later onset of Alzheimer's disease. We therefore explored the relationship between decline in episodic memory and β-amyloid using positron emission tomography (PET) and [{sup 11}C]AZD2184, a radioligand with potential to detect low levels of amyloid deposits. Healthy elderly subjects with declining (n = 10) or stable (n = 10) episodic memory over 15 years were recruited from the population-based Betula study and examined with PET. Brain radioactivity was measured after intravenous administration of [{sup 11}C]AZD2184. The binding potential BP{sub ND} was calculated using linear graphical analysis with the cerebellum as reference region. The binding of [{sup 11}C]AZD2184 in total grey matter was generally low in the declining group, whereas some binding could be observed in the stable group. Mean BP{sub ND} was significantly higher in the stable group compared to the declining group (p = 0.019). An observation was that the three subjects with the highest BP{sub ND} were ApoE ε4 allele carriers. We conclude that cognitive decline in the general population does not seem to stand by itself as an early predictor for amyloid deposits. (orig.)

  20. History of formation of forests in the plain part of Ukraine in the Holocene

    International Nuclear Information System (INIS)

    Full text: The authors analyzed and generalized the results of palynological and radiocarbon-dating studies of Holocene deposits of the forest, forest-steppe and steppe zones of Ukraine. Based on the obtained data, we reconstructed the pattern of main changes of vegetation and climate starting from 10,300 years BP. We consider changes in forest vegetation of the studied area in the Early (PB-1, PB-2, BO-1, BO-2, BO-3), Middle (AT-1, AT-2, AT-3, SB-1, SB-2, SB-3) and Late Holocene. For most important forest-forming trees (species of Pinus, Betula, Alnus, Quercus, Tilia, Carpinus, Fagus etc.), the main periods of their maximum participation in Ukrainian forest vegetation were identified. Broadleaf forests and mixed forests with participation of broadleaf trees were most widespread in Ukraine 4,500-6,200 years BP. During the second phase of the Atlantic time of the Holocene the northern border of the steppe zone in Ukraine was stable. Expansion of forest communities in the steppe zone progressed through gradual increase of forest areas that originally occurred in flood plains and ravines. (author)

  1. FAGALES POLLEN IN THE ATMOSPHERE OF TIMIŞOARA, ROMANIA (2000-2007

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2013-12-01

    Full Text Available This work presents the first aerobiological monitoring results for Fagales in the city of Timişoara (Romania using a volumetric spore-trap (Lanzoni VPPS 2000 which is now the most commonly used aerobiologic measurement instrument in Europe. The aim of this study was to determine characteristics of Fagales pollen occurrence in outdoor environment of Timişoara by measuring daily pollen concentrations. The concept of the atmospheric pollen season was used. Sampling was carried out during 8 years, starting in 2000 until 2007. Fagales allergenic pollen appear in the area of Timişoara only from the end of January to the end of May. The data showed that during the early spring the atmospheric pollen season for these allergenic species is highly variable. There were considerable variations in start date, atmospheric pollen season, peak concentration, date of peak. The concentration of airborne Fagales pollen in Timişoara and the correlations with some meteorological parameters have been examined. Daily pollen concentrations presented negative correlation with daily average relative humidity, and slightly positive with wind speed using Spearman’s correlation coefficients. Fagales pollen concentrations represent important values in the atmosphere of Timişoara, which means they may to cause pollinosis in its population. The best-represented pollen type through the entire period was Betula.

  2. Boreal Forests of Kamchatka: Structure and Composition

    Directory of Open Access Journals (Sweden)

    Markus P. Eichhorn

    2010-09-01

    Full Text Available Central Kamchatka abounds in virgin old-growth boreal forest, formed primarily by Larix cajanderi and Betula platyphylla in varying proportions. A series of eight 0.25–0.30 ha plots captured the range of forests present in this region and their structure is described. Overall trends in both uplands and lowlands are for higher sites to be dominated by L. cajanderi with an increasing component of B. platyphylla with decreasing altitude. The tree line on wet sites is commonly formed by mono-dominant B. ermanii forests. Basal area ranged from 7.8–38.1 m2/ha and average tree height from 8.3–24.7 m, both being greater in lowland forests. Size distributions varied considerably among plots, though they were consistently more even for L. cajanderi than B. platyphylla. Upland sites also contained a dense subcanopy of Pinus pumila averaging 38% of ground area. Soil characteristics differed among plots, with upland soils being of lower pH and containing more carbon. Comparisons are drawn with boreal forests elsewhere and the main current threats assessed. These forests provide a potential baseline to contrast with more disturbed regions elsewhere in the world and therefore may be used as a target for restoration efforts or to assess the effects of climate change independent of human impacts.

  3. Root biomass and underground C and N storage of the primitive Korean pine and broad-leaved forest and its different succession stages in Changbai Mountain, northeast China

    Institute of Scientific and Technical Information of China (English)

    YANG Liyun; LUO Tianxiang; WU Songtao

    2006-01-01

    This paper studied root biomass and underground carbon (C) and nitrogen (N) storage of a more than 200-year-old primitive Korean pine and broad-leaved forest and its two 20- and 80-year-old secondary Populus davidiana and Betula platyphylla forests in Changbai Mountain,northeast China.The results showed that with forest succession,the root biomass of 20-year-old,80-year-old,and primitive forests was 2.437,2.742,and 4.114 kg/m2,respectively.The root C storage was 1.113,1.323,and 2.023kg/m2,soil C storage was 11.911,11.943,and 12.587 kg/m2,and underground C storage was 13.024,13.266,and 14.610kg/m2,respectively,while the root N storage was 0.035,0.032,and 0.038 kg/m2,soil N storage was 1.208,1.222,and 0.915 kg/m2,and underground N storage was 1.243,1.254,and 0.955 kg/m2,respectively,which indicated that along with forest succession,the forest underground became a potential"carbon sink,"whereas underground N storage did not change obviously.

  4. The amount of carbon in the undergrowth biomass of main types of forests stands in Poland

    Directory of Open Access Journals (Sweden)

    Janyszek Sławomir

    2015-12-01

    Full Text Available The sequestration of carbon in biomass of herb and moss layers of forest ecosystems is relatively less studied, than analogical processes in trees biomass and soil organic mass. The paper presents mean values of carbon concentration and mean amounts of dry mass of plant material in the herb and moss layer of phytocoenoses formed under canopy of stands of main forest-forming species of trees in Poland. The parameters were studied for beech, birch, oak, alder, pine, fir and spruce forest stands, for most of the particular age classes. The studied plots were contained in following plant associations and communities: Ribo nigri-Alnetum, Fraxino-Alnetum, Galio odorati-Fagetum, Luzulo luzuloidis-Fagetum, Molinio caeruleae-Quercetum roboris, Calamagrostio-Quercetum petraeae, Abietetum polonicum, Abieti-Piceetum montanum, Calamagrostio villosae-Piceetum, as well as anthropogenic communities: Betula pendula comm. on Leucobryo-Pinetum habitat, Larix decidua comm. on Tilio-Carpinetum habitat, Pinus sylvestris comm. on Tilio-Carpinetum habitat, Picea abies comm. on Luzulo pilosae-Fagetum habitat (in lowland and Picea abies comm. on Luzulo luzuloidis-Fagetum habitat (in lower mountain localities. The relatively highest carbon amount was observed in oak forests, pine forests and in older age classes of lowland beech forest, where the carbon concentration in dry mass reaches from 60 to 81%. The lowest concentrations were determined for lowland spruce forests, highland fir forests and for alder forests. The carbon concentration reached in these types of ecosystems from 39 to 41%.

  5. Study of the betulin enriched birch bark extracts effects on human carcinoma cells and ear inflammation

    Directory of Open Access Journals (Sweden)

    Dehelean Cristina A

    2012-11-01

    Full Text Available Abstract Background Pentacyclic triterpenes, mainly betulin and betulinic acid, are valuable anticancer agents found in the bark of birch tree. This study evaluates birch bark extracts for the active principles composition. Results New improved extraction methods were applied on the bark of Betula pendula in order to reach the maximum content in active principles. Extracts were analyzed by HPLC-MS, Raman, SERS and 13C NMR spectroscopy which revealed a very high yield of betulin (over 90%. Growth inhibiting effects were measured in vitro on four malignant human cell lines: A431 (skin epidermoid carcinoma, A2780 (ovarian carcinoma, HeLa (cervix adenocarcinoma and MCF7 (breast adenocarcinoma, by means of MTT assay. All of the prepared bark extracts exerted a pronounced antiproliferative effect against human cancer cell lines. In vivo studies involved the anti-inflammatory effect of birch extracts on TPA-induced model of inflammation in mice. Conclusions The research revealed the efficacy of the extraction procedures as well as the antiproliferative and anti-inflammatory effects of birch extracts.

  6. Effects of invasive European bird cherry (Prunus padus) on leaf litter processing by aquatic invertebrate shredder communities in urban Alaskan streams

    Science.gov (United States)

    Roon, David A.; Wipfli, Mark S.; Wurtz, Tricia L.

    2014-01-01

    European bird cherry (Prunus padus) (EBC) is an invasive ornamental tree that is spreading rapidly in riparian forests of urban Alaska. To determine how the spread of EBC affects leaf litter processing by aquatic invertebrate shredders, we conducted complementary leaf pack experiments in two streams located in Anchorage, Alaska. The first experiment contrasted invasive EBC with three native tree species—thin-leaf alder (Alnus tenuifolia), paper birch (Betula neoalaskana), and black cottonwood (Populus trichocarpa)—in one reach of Chester Creek; finding that EBC leaf litter broke down significantly faster than birch and cottonwood, but at a similar rate to alder. The second experiment contrasted EBC with alder in four reaches of Campbell and Chester creeks; finding that while EBC leaf litter broke down significantly faster than alder in Chester Creek, EBC broke down at a similar rate to alder in Campbell Creek. Although EBC sometimes supported fewer shredders by both count and mass, shredder communities did not differ significantly between EBC and native plants. Collectively, these data suggest that invasive EBC is not currently exhibiting strong negative impacts on leaf litter processing in these streams, but could if it continues to spread and further displaces native species over time.

  7. Use of mosses and lichens for the evaluation of the radioactive fallout, deposits and flows under forest-cover

    International Nuclear Information System (INIS)

    Following the Chernobyl nuclear accident in April 1986, samples of 24 moss and lichen species were collected from a variety of forest types - young or mature spruce [Picea abies], beech [Fagus sylvatica], birch [Betula alba] or oak [Quercus robur] stands, and from bark, stump, dead branch, soil drainage channel or stream positions - between October 1986 and September 1988. Caesium radioisotopes (134Cs and 137Cs) were measured. Variability of contamination between species was relatively small; variability of contamination between sites was larger: greater contamination was recorded for samples (1) from forest edges exposed in May 1986 to contaminated precipitation, (2) in forest gaps, particularly in spruce stands and (3) on tree stems with greater stemflow, particularly beech. Radiocaesium 'ecological' half-life was shorter for mosses: e.g. about 18 months for Pleurozium schreberi (a terrestrial moss); and about 21 months for Hypogymnia physodes (a tree stem lichen). Samples from the Ardennes region recorded shorter half lives than those from the Gaume; this is attributed to differences in mean annual precipitation (respectively, 1200 and 800 mm). Depending on bryophyte morphology (rather than density beneath forest canopy), between 15 and 50% of original contamination had not reached the soil 30 months after the accident

  8. Wood Resources of Thailand

    International Nuclear Information System (INIS)

    According to 'The Book of Siamese Plant Names' issued by the Royal Forest Department in 1948, exactly one thousand species of trees in Thailand had been identified before that date. Many more species, including such remarkable ones as Prunus .javanica (T & B) Mig. and Betula anoides Ham., which are typical of the temperate zone, were later added to the list. Of the total number mentioned, 280 species have been registered under the Thai Forest Act as reserved species which cannot be cut without permission from the authority. Timbers of real commercial value, however, are comparatively few in number and those with high production figures for the fiscal year 1966 are listed in Table I where the wood density of each species is also given. Only twenty years ago, very few species superior in natural durability, strength, dimensional stability and working quality were offered in local timber markets, including Bangkok. Recently, as the demand for timbers increased enormously and with the development of wood-consuming industry, nearly all tree species have become valuable. Some soft species, such as Salmalia malabarica Schott & Endl., which were previously considered to be unusable, have also become important raw materials for pulp and paper, plywood and particle-board manufacturing. Trees of smaller size are also continuously needed for the fabrication of construction materials

  9. The Pleistocene biogeography of eastern North America: A nonmigration scenario for deciduous forest

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. [Argonne National Lab., IL (United States). Environmental Research Div.; Iltis, H. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Botany

    1998-12-31

    The current reconstruction of the vegetation of eastern North America at the last glacial maximum postulates a very wide zone of tundra and boreal forest south of the ice. This reconstruction requires that the deciduous forest retreated far to the south. The authors believe that this reconstruction is seriously in error. Geologic evidence for glacial activity or tundra is absent from the southern Appalachians. Positive evidence for boreal forest is based on pollen identifications for Picea, Betula, and Pinus, when in reality southern members of these genera have pollen that cannot be distinguished from that of northern members. Further, pollen of typical southern species such as oaks and hickories occurs throughout profiles that past authors had labeled boreal. Pollen evidence for a far southern deciduous forest refuge is lacking. Data on endemics are particularly challenging for the scenario in which deciduous forest migrated to the south and back. The southern Appalachian region is rife with endemics that are often extreme-habitat specialists unable to migrate. The previously glaciated zone is almost completely lacking in endemics. Outlier populations, range boundaries, and absence of certain hybrids all argue against a large boreal zone. The new reconstruction postulates a cold zone no more than 75--100 miles wide south of the ice in the East.

  10. Suitability of thermoluminescence, chemiluminescence, ESR and viscosity measurements as detection method for the irradiation of medicinal herbs

    International Nuclear Information System (INIS)

    Chemiluminescence, electron spin resonance, thermoluminescence and viscosity measurements have been investigated for their suitability as detection method for the irradiation of the medicinal herbs anise seeds (anisi fructus), valerian roots (valerianae radix), redberry leaves (uvae ursi folium), birch leaves (betulae folium), greek hay seeds (foenugraeci semen), cayenne pepper (capsici fructus acer), black-aldertee bark (frangulae cortex), fennel fruits (feoniculi fructus), rose hip shells (cynosbati fructus), coltsfoot (farfarae folium), acorus roots (calami rhizoma), chamomile flowers (matricariae flos), caraway (carvi fructus), lavender flowers (lavandulae flos), linseed (lini semen), lime tree flowers (tiliae flos), St. Mary's thistle fruit (cardui mariae herba), lemon balm (melissae folium), java tea (orthosiphonis folium), peppermint (menthae piperitae folium), sage leaves (salviae folium), scouring rush (equiseti herba), senna leaves (sennae folium), plantain herbs (plantaginis lanceolata herba), thyme herbs (thymi herba), juniper berries (juniperi fructus), hawthorne herbs (crataegi folium), wheat starch (amylum tritici) and wormwood (absinthii herba). Depending on the herbs, the methods used were more or less suitable. Chemiluminescence measurements showed the smallest differences between untreated and irradiated samples whereas thermoluminescence measurements on isolated minerals from the vegetable drugs gave better results. In some herbs radiation-specific radicals could be identified by ESR spectroscopy. Viscosity measurement is suitable for some herbs as fast and inexpensive method for screening. (orig.)

  11. Screening Analyses of Pinosylvin Stilbenes, Resin Acids and Lignans in Norwegian Conifers

    Directory of Open Access Journals (Sweden)

    Anne Fiksdahl

    2006-01-01

    Full Text Available The content and distribution of stilbenes and resin acids in Scots pine (Pinus sylvestris and spruce (Picea abies, sampled in central Norway, have been examined. The contents of pinosylvin stilbenes in pine heartwood/living knots were 0.2-2/2-8 % (w/w. No stilbenes could be detected in spruce (Picea abies. The resin acid contents of pine sapwood/heartwood and knots were 1-4 and 5-10 % (w/w, respectively. Minor amounts of resin acids (< 0.2/< 0.04 %w/w were identified in spruce wood/knots. The lignan content in knots of Norwegian spruce was 6.5 % (w/w. Diastereomerically pure hydroxymatairesinol (HMR, 84 % of total lignans was readily isolated from this source since only minor quantities (2.6 % of total lignans of the allo-HMR diastereomer was detected. Insignificant amounts of lignans were present in the sapwood. Lignans could not be detected in the sapwood or knots of Norwegian sallow (Salix caprea, birch (Betula pendula or juniper (Juniperus communis.

  12. Scale correlation between vegetation and soil in larch forest, NE China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    After the analysis on the linages of species, the fractal dimensions of vegetation and soil in a managed larch(Larix gmelini) forest in Daxingan Mountains, NE China were estimated separately, and their scale correlation was discussed. (1) The dominant species of the larch forest, larch and the important accompany species, birch(Betula platyphylla) were homogeneously distributed along the transect. The other species were heterogeneous, and can be divided into three groups located on the right , left and central parts of th transect respectively. The transect can be separated into two parts at the position for the 29th quadrat(580m). (2) The fractal dimension in the large scale range from 200 to 400m was lower than that in the small scale range from 0 to 200m in the forest, indicating the different variation regularities of spatial heterogeneity in different scale ranges. The inflection point at 200m was one of the key scales of spatial hierarchy of the larch forest. (3) The scale variation of the forest was correlated with that of soil pH on large scales, which reflected the indirect control of the dominant species to the spatial pattern and species distribution of understories by changing soil acidity in the forest and the indirect effects of forest management.

  13. Tc1-like transposable elements in plant genomes

    Science.gov (United States)

    2014-01-01

    Background The Tc1/mariner superfamily of transposable elements (TEs) is widespread in animal genomes. Mariner-like elements, which bear a DDD triad catalytic motif, have been identified in a wide range of flowering plant species. However, as the founding member of the superfamily, Tc1-like elements that bear a DD34E triad catalytic motif are only known to unikonts (animals, fungi, and Entamoeba). Results Here we report the identification of Tc1-like elements (TLEs) in plant genomes. These elements bear the four terminal nucleotides and the characteristic DD34E triad motif of Tc1 element. The two TLE families (PpTc1, PpTc2) identified in the moss (Physcomitrella patens) genome contain highly similar copies. Multiple copies of PpTc1 are actively transcribed and the transcripts encode intact full length transposase coding sequences. TLEs are also found in angiosperm genome sequence databases of rice (Oryza sativa), dwarf birch (Betula nana), cabbage (Brassica rapa), hemp (Cannabis sativa), barley (Hordium valgare), lettuce (Lactuta sativa), poplar (Populus trichocarpa), pear (Pyrus x bretschneideri), and wheat (Triticum urartu). Conclusions This study extends the occurrence of TLEs to the plant phylum. The elements in the moss genome have amplified recently and may still be capable of transposition. The TLEs are also present in angiosperm genomes, but apparently much less abundant than in moss. PMID:24926322

  14. Responses of gas exchange and plant hydraulic conductance to water deficit in silver birch trees growing under increasing atmospheric humidity

    Science.gov (United States)

    Sellin, Arne; Kupper, Priit

    2013-04-01

    Climate change scenarios predict increase in air temperature by 3.5-5° C and precipitation by 5-30% in boreal and northern temperate regions of Europe by the end of the century. On the other hand, climate extremes including heat waves and droughts are projected to become more frequent and last longer across Europe over the 21st century. Increasing atmospheric humidity inevitably occurring with more frequent rainfall events reduce water fluxes through the vegetation, and have an effect on the structure of leaves and vascular tissues, plant hydraulic properties, biomass allocation, nutrient uptake and growth (Tullus et al. 2012). We investigated fast and long-term effects of water deficit on plant water status, gas exchange and hydraulic conductance on saplings of silver birch (Betula pendula) growing under artificially manipulated air humidity in an experimental forest ecosystem at the Free Air Humidity Manipulation site (http://www.lote.ut.ee/FAHM/in-english; Kupper et al. 2011). Fast-developing water deficit was imposed by letting cut sample branches to dehydrate in open-air conditions, long-term water deficit was generated by seasonal drought. The fast-imposed water deficit estimated by leaf (ΨL) or branch water status (ΨB) had highly significant (P

  15. Long-term ecological behaviour of abandoned uranium mill tailings. 1

    International Nuclear Information System (INIS)

    Inactive uranium mill tailings were surveyed in the Province of Ontario to describe their surface characteristics, identify naturally invading biota, and determine essential chemical and physical parameters associated with the tailings. Inactive tailings sites can have wet areas, tailings completely covered with water, and dry areas. In the wet areas of most sites, wetland vegetation stands were found which were dominated by species of cattails (Typhaceae), along with some species of rushes (Juncaceae) and sedges (Cyperceae). Dry areas of the tailings exhibited a variety of surface features which are often a reflection of different amelioration efforts. Most of the indigenous species of vascular plants identified on dry areas of the tailings occurred only sporadically. Invading plants found on most sites were the tree species, trembling aspen (Populus tremuloides) and paper birch (Betula papyrifera). Elemental concentration and some physical characteristics of the tailings collected from a depth of 0-20 cm were determined. Uptake of heavy metals and radionuclides were evaluated in trees found in the dry areas and in cattails (Typha latifolia) in the wetland areas. Water bodies on tailings and surface water leaving the tailings, before and after treatment, were characterized in this survey. Aquatic bryophytes have invaded some water bodies on the tailings, and acid tolerant algae were evident in most of the water associated with the tailings. Ecological processes occurring on inactive uranium mill tailings which were identified in this survey are essential in evaluating the long-term fate of these waste sites

  16. Changes in petiole hydraulic properties and leaf water flow in birch and oak saplings in a CO2-enriched atmosphere

    International Nuclear Information System (INIS)

    This study examined the water flow and petiole hydraulic properties in the individual leaves of Betula maximowicziana Regel and ring-porous Quercus mongolica Fish. ex Ledeb ssp. crispula Menitsky. The aim of the study was to examine the relationship between water flow, hydraulic properties and elevated carbon dioxide (CO2). The effects of elevated CO2 on sun and shade leaves of 2 petioles were investigated in order to examine structural changes in response to CO2. The study was conducted at the Sapporo Experimental Forest in Japan, where a free air CO2 enrichment system was used to maintain CO2 levels. Results of the study demonstrated that elevated CO2 levels consistently decreased water flow, including leaf-specific hydraulic conductivity and total vessel area of the petiole in leaves exposed to the sun. Elevated CO2 levels had no impact on the hydraulic conductivity of shade leaves. It was concluded that changes in water flow were also associated with changes in petiole hydraulic properties. 57 refs., 2 tabs., 4 figs

  17. Essential and non-essential elements in natural vegetation in southern Norway: Contribution from different sources

    Energy Technology Data Exchange (ETDEWEB)

    Nordløkken, Marit, E-mail: marit.nordlokken@ntnu.no; Berg, Torunn; Flaten, Trond Peder; Steinnes, Eiliv

    2015-01-01

    Concentrations of essential and non-essential elements in five widespread species of natural boreal vegetation were studied with respect to seasonal variation and contribution from different sources. The plant species included in the study were Betula pubescens, Sorbus aucuparia, Vaccinium myrtillus, Vaccinium uliginosum, Calluna vulgaris and Deschampsia flexuosa. Concentrations of elements essential to plants remained essentially constant or decreased slightly throughout the growing season. Concentrations of most non-essential elements increased or tended to increase on a dry mass basis from June to July as well as from July to September. The increasing trend for these elements was observed for all species except C. vulgaris. Principal component analysis (PCA) of the material indicated a common source for many of the non-essential elements; Sc, Ti, V, Ga, As, Y, Sb, lanthanides, Pb, Bi, and U, i.e. both elements presumably of geogenic origin and elements associated with trans-boundary air pollution. Uptake by plant roots appeared to be the main source of nutrient elements as well as some non-essential elements. - Highlights: • Concentrations of elements in different plant species were studied. • Changes in concentrations during a growing season were identified. • PCA indicated a common source for many of the non-essential elements. • Uptake by roots appeared to be the plant’s main source of nutrient elements.

  18. Combining microtomy and confocal laser scanning microscopy for structural analyses of plant-fungus associations.

    Science.gov (United States)

    Rath, Magnus; Grolig, Franz; Haueisen, Janine; Imhof, Stephan

    2014-05-01

    The serious problem of extended tissue thickness in the analysis of plant-fungus associations was overcome using a new method that combines physical and optical sectioning of the resin-embedded sample by microtomy and confocal microscopy. Improved tissue infiltration of the fungal-specific, high molecular weight fluorescent probe wheat germ agglutinin conjugated to Alexa Fluor® 633 resulted in high fungus-specific fluorescence even in deeper tissue sections. If autofluorescence was insufficient, additional counterstaining with Calcofluor White M2R or propidium iodide was applied in order to visualise the host plant tissues. Alternatively, the non-specific fluorochrome acid fuchsine was used for rapid staining of both, the plant and the fungal cells. The intricate spatial arrangements of the plant and fungal cells were preserved by immobilization in the hydrophilic resin Unicryl™. Microtomy was used to section the resin-embedded roots or leaves until the desired plane was reached. The data sets generated by confocal laser scanning microscopy of the remaining resin stubs allowed the precise spatial reconstruction of complex structures in the plant-fungus associations of interest. This approach was successfully tested on tissues from ectomycorrhiza (Betula pendula), arbuscular mycorrhiza (Galium aparine; Polygala paniculata, Polygala rupestris), ericoid mycorrhiza (Calluna vulgaris), orchid mycorrhiza (Limodorum abortivum, Serapias parviflora) and on one leaf-fungus association (Zymoseptoria tritici on Triticum aestivum). The method provides an efficient visualisation protocol applicable with a wide range of plant-fungus symbioses. PMID:24249491

  19. Surface pollen and its relationship to vegetation in the Zoige Basin, eastern Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    Furong LI; Yan ZHAO; Jinghui SUN; Wenwei ZHAO; Xiaoli GUO; Ke ZHANG

    2011-01-01

    We use a data set of 23 surface pollen samples from moss polsters in the Zoige Basin to explore the relationship between modem pollen assemblages and contemporary vegetation patterns.The surface pollen samples spanned four types of plant communities:Carex muliensis marsh,Stipa and Kobresia meadow,Carexdominated forb meadow and Sibiraea angustata scrub.Principal-components analysis(PCA)was used to determine the relationships between modem pollen and vegetation and environmental variables.The results show that the pollen assemblages of surface moss samples generally reflect the features of the modem vegetation,basically similar in the vegetation types and the dominant genera; however,they don't show a very clear distinction between different communities.Our results also demonstrate that pollen representation of different families or genus varied.Some tree taxa,such as Pinus and Betula,and herb types,such as Artemisia are over-represented,while Asteraceae,Ranunculaceae and Cyperaceae are moderately represented,and Poaceae and Rosaceae are usually under-represented in our study region.PCA results indicate that the distribution of vegetation in the Zoige Basin is mainly controlled by precipitation and altitude.

  20. [Analysis on factors affecting net primary productivity distribution in Changbai Mountain based on process model for landscape scale].

    Science.gov (United States)

    Zhang, Na; Yu, Guirui; Yu, Zhenliang; Zhao, Shidong

    2003-05-01

    Based on the data received from remote sensing images, the spatial distribution of annual net primary productivity (NPP) was simulated by the process model (EPPML), and the relationships between annual NPP and environmental conditions were analyzed. The results showed that NPP in 1995 was 0.680 kg C.m-2.yr.-1, mostly ranging from 0.105 to 1.241 kg C.m-2.yr.-1, accounting for 82.1%. The highest NPP (1.084 kg C.m-2.yr.-1) appears in mixed broad-leaved and Korean pine forest. Environmental conditions decide the main trend of the spatial distribution of annual NPP (Carbon) in Changbai Mountain. Soil water content had a negative correlativity with NPP, and the correlation coefficient (R) was -0.65. Therefore, water was sufficient for the growth of plants in Changbai Mountain. NPP was highly correlated with LAI (R = 0.81). When LAI was greater than 4-5 m2.m-2, NPP became saturated. NPP was also highly correlated with canopy transpiration (R = 0.77). The response of NPP on environmental conditions, LAI and canopy transpiration in Betula ermanii and broad-leaved forests were different from those in other vegetation. PMID:12924113

  1. Long-Term Arctic Peatland Dynamics, Vegetation and Climate History of the Pur-Taz Region, Western Siberia

    Science.gov (United States)

    Peteet, Dorothy; Andreev, Andrei; Bardeen, William; Mistretta, Francesca

    1998-01-01

    Stratigraphic analyses of peat composition, LOI, pollen, spores, macrofossils, charcoal, and AMS ages are used to reconstruct the peatland, vegetation and climatic dynamics in the Pur-Taz region of western Siberia over 5000 years (9300 - 4500 BP). Section stratigraphy shows many changes from shallow lake sediment to different combinations of forested or open sedge, moss, and Equisetum fen and peatland environments. Macrofossil and pollen data indicate that Larix sibirica and Betula pubescens trees were first to arrive, followed by Picea obovata. The dominance of Picea macrofossils 6000-5000 BP in the Pur-Taz peatland along with regional Picea pollen maxima indicate warmer conditions and movement of the spruce treeline northward at this time. The decline of pollen and macrofossils from all of these tree species in uppermost peats suggests a change in the environment less favorable for their growth, perhaps cooler temperatures and/or less moisture. Of major significance is the evidence for old ages of the uppermost peats in this area of Siberia, suggesting a real lack of peat accumulation in recent millennia or recent oxidation of uppermost peat.

  2. Net transfer of carbon between ectomycorrhizal tree species in the field

    International Nuclear Information System (INIS)

    Different plant species can be compatible with the same species of mycorrhizal fungi and be connected to one another by a common mycelium. Transfer of carbon nitrogen and phosphorus through interconnecting mycelia has been measured frequently in laboratory experiments, but it is not known whether transfer is bidirectional, whether there is a net gain by one plant over its connected partner, or whether transfer affects plant performance in the field. Laboratory studies using isotope tracers show that the magnitude of one-way transfer can be influenced by shading of 'receiver' plants fertilization of 'donor' plants with phosphorus, or use of nitrogen-fixing donor plants and non-nitrogen-fixing receiver plants indicating that movement may be governed by source–sink relationships. Here we use reciprocal isotope labelling in the field to demonstrate bidirectional carbon transfer between the ectomycorrhizal tree species Betula papyrifera and Pseudotsuga menziesii, resulting in net carbon gain by P. menziesii. Thuja plicata seedlings lacking ectomycorrhizae absorb small amounts of isotope, suggesting that carbon transfer between B. papyrifera and P. menziesii is primarily through the direct hyphal pathway. Net gain by P. menziesii seedlings represents on average 6% of carbon isotope uptake through photosynthesis. The magnitude of net transfer is influenced by shading of P. menziesii, indicating that source–sink relationships regulate such carbon transfer under field conditions

  3. Analysis of organic acids in selected forest litters of Northeast China

    Institute of Scientific and Technical Information of China (English)

    SONGJin-feng; CUIXiao-yang

    2003-01-01

    Larch (Larix olgensis), Manchurian ash (Fraxinus mandshurica), Korean pine (Pinus koraiensis) and White birch (Betula platyphylla) are the major planting species in northeast China. The samples of forest litters were collected from the stands of the above 4 species in Laoyeling and Jianlagou experiment stations of Maorshan Exp. Forest Farm (45°12′-45°30′N,127°30′-127°48′E), Northeast Forestry University, in early October 2002. Quantitative analysis and qualitative analysis were carried out on the organic acids existing in freshly fallen litters (L layer) and hemi-decomposed litters (F layer) of the four forest species by using Gas Chromatogram system. A wide variety of organic acids were identified, including oxalic, malonic, fumaric,succinic, maleic, malic, citric, C16:0, C18:0, C18:1, C18:2, C18:3 and C20:0 acids. In respect of L litters of all samples, the oxalic acid content (over 30 mg/g) was the highest of the seven low-molecular-weight organic acids identified, while the content of oleic or linoleic (above 40 mg/g) was found to be highest among the six high aliphatic acids identified. As to F litters, oxalic acid content was also the highest, followed by linoleic and oleic. For the same tree species or the same forest, the kinds and contents of organic acids in L litters were more abundant than that in F litters.

  4. The role of selected tree species in industrial sewage sludge/flotation tailing management.

    Science.gov (United States)

    Mleczek, Mirosław; Rutkowski, Paweł; Niedzielski, Przemysław; Goliński, Piotr; Gąsecka, Monika; Kozubik, Tomisław; Dąbrowski, Jędrzej; Budzyńska, Sylwia; Pakuła, Jarosław

    2016-11-01

    The aim of the study was to estimate the ability of ten tree and bush species to tolerate and accumulate Cd, Cu, Pb, Zn, and As species [As(III), As(V), and total organic arsenic] in industrial sewage sludge extremely contaminated with arsenic (almost 27.5 g kg(-1)) in a pot experiment. The premise being that it will then be possible to select the most promising tree/bush species, able to grow in the vicinity of dams where sewage sludge/flotation tailings are used as landfill. Six of the ten tested tree species were able to grow on the sludge. The highest content of total As was observed in Betula pendula roots (30.0 ± 1.3 mg kg(-1) DW), where the dominant As species was the toxic As(V). The highest biomass of Quercus Q1 robur (77.3 § 2.6 g) and Acer platanoides (76.0 § 4.9 g) was observed. A proper planting of selected tree species that are able to thrive on sewage sludge/flotation tailings could be an interesting and promising way to protect dams. By utilizing differences in their root systems and water needs, we will be able to reduce the risk of fatal environmental disasters. PMID:27348264

  5. Response of seedlings of different tree species to elevated C02 in Changbai Mountain

    Institute of Scientific and Technical Information of China (English)

    DAILi-min; JILan-zhu; WANGMiao; LIQiu-rong

    2003-01-01

    Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Lanx olgensis,Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 pmol· mol-1) and ambient CO2 (400μmol· mol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species.The broad-leaf tree species were more sensitive to the elevated CO2than conifer tree species. All seedlings showed a photo-synthetic acclimation to Iong-term elevated CO2.

  6. Online Measurement of Real-Time Cytotoxic Responses Induced by Multi-Component Matrices, such as Natural Products, through Electric Cell-Substrate Impedance Sensing (ECIS

    Directory of Open Access Journals (Sweden)

    Adyary Fallarero

    2015-11-01

    Full Text Available Natural products are complex matrices of compounds that are prone to interfere with the label-dependent methods that are typically used for cytotoxicity screenings. Here, we developed a label-free Electric Cell-substrate Impedance Sensing (ECIS-based cytotoxicity assay that can be applied in the assessment of the cytotoxicity of natural extracts. The conditions to measure the impedance using ECIS were first optimized in mice immortalized hypothalamic neurons GT1-7 cells. The performance of four natural extracts when tested using three conventional cytotoxicity assays in GT1-7 cells, was studied. Betula pendula (silver birch tree was found to interfere with all of the cytotoxicity assays in which labels were applied. The silver birch extract was also proven to be cytotoxic and, thus, served as a proof-of-concept for the use of ECIS. The extract was fractionated and the ECIS method permitted the distinction of specific kinetic patterns of cytotoxicity on the fractions as well as the extract’s pure constituents. This study offers evidence that ECIS is an excellent tool for real-time monitoring of the cytotoxicity of complex extracts that are difficult to work with using conventional (label-based assays. Altogether, it offers a very suitable cytotoxicity-screening assay making the work with natural products less challenging within the drug discovery workflow.

  7. The rhizosphere and PAH amendment mediate impacts on functional and structural bacterial diversity in sandy peat soil

    International Nuclear Information System (INIS)

    To reveal the degradation capacity of bacteria in PAH polluted soil and rhizosphere we combined bacterial extradiol ring-cleavage dioxygenase and 16S rRNA analysis in Betula pubescens rhizoremediation. Characterisation of the functional bacterial community by RFLP revealed novel environmental dioxygenases, and their putative hosts were studied by 16S rRNA amplification. Plant rhizosphere and PAH amendment effects were detected by the RFLP/T-RFLP analysis. Functional species richness increased in the birch rhizosphere and PAH amendment impacted the compositional diversity of the dioxygenases and the structural 16S rRNA community. A shift from an Acidobacteria and Verrucomicrobia dominated to an Alpha- and Betaproteobacteria dominated community structure was detected in polluted soil. Clone sequence analysis indicated catabolic significance of Burkholderia in PAH polluted soil. These results advance our understanding of rhizoremediation and unveil the extent of uncharacterized functional bacteria to benefit bioremediation by facilitating the development of the molecular tool box to monitor bacterial populations in biodegradation. - The bacterial community analysis using 16S rRNA and extradiol dioxygenase marker genes in rhizoremediation revealed both a rhizosphere and a PAH-pollution effect.

  8. Common environmental allergens causing respiratory allergy in India.

    Science.gov (United States)

    Singh, A B; Kumar, Pawan

    2002-03-01

    Respiratory allergy affects all age groups but the children are the worst affected by the respiratory allergy. Bioparticles from different biological sources are the main cause of allergy. Pollen grains, fungal spores, insect and other materials of biological origin form the most important allergen load in the air. For the efficient diagnosis of the allergy and its effective treatment it is very important to know about the prevalence, seasonal and annual variations of aeroallergens of the area. India being the climatically diversed country, there is diversity in the flora and fauna of different parts of the country. Atmospheric surveys carried out in different parts of India reveal that, Alanus nitida, Amarantus spinosus, Argemone mexicana Cocos nucifera, Betula utilis, Borasus flabellifer, Caraica papaya, Cedrus deodara, Cassia fistula, Parthenium, Chenopodium album, Dodonaea viscosa, Malotus phillipensis, Plantago ovata, Prosopis juliflora, Ricinus communis, Holoptelea intergifolia are the allergenically important pollens of the country. Among the fungal aeroallergens, Alternaria, Candida aibieans, Aspergillus versicolor, Aspergillus terreus, Aspergillus japonicus, Cladosporium cladosporoides, Fusarium roseum, Ganoderma lucidum,Neurospora sitophila Helminthosporium, Ustilago trtici, Uromyses are important allergens. Dust mites D. farinae, D.pteronyssinus are also important source of inhalant allergens particularly in the coastal areas of the country. Cockroaches, beetles, weevils, mosquitoes, house flies also contribute towards the aeroallergen load and are allergenically implicated. Avoidance of the indoor and outdoor aeroallergens is recommended for better management of respiratory allergy. PMID:12003301

  9. Study on the Relationship between Forest Fire and Forest Types in Saihanba Forest Center%塞罕坝机械林场森林类型与林火关系的研究

    Institute of Scientific and Technical Information of China (English)

    于士涛

    2014-01-01

    该文通过对塞罕坝机械林场野外调查获取实地数据来分析林场的林型特征与火灾的关系,得出结论如下:樟子松纯林属于极易燃类型;白桦林属于中等易燃类型;蒙古栎林属较易燃类型;落叶松和白桦的混交林内属于较难燃类型;落叶松、樟子松和云杉的混交林内属于较易燃类型。%In this dissertation datum gotten by some field investigation was also used to analyze the rela⁃tion between forest fire and the character of forest. The main conclusions as follows:Forest of L. gmelinii is difficult to burn;forest of Pinus sylvestris var. mongolica Litv is very inflammable;forest of Betula platy⁃phylla Suk is mid-inflammable;forest of Quercus mongolica Fisch is correspondingly inflammable. Mixed for⁃est of L. gmelinii and P. sylvestris var. mongolica Litv is uninflammable;mixed forest of L. gmelinii,P. syl⁃vestris var. mongolica Litv and Picea asperata Mast is correspondingly inflammable.

  10. Variance analysis on different trees species depending on soil type – uncontaminated and heavy metals contaminated ones

    Directory of Open Access Journals (Sweden)

    Monica MARIAN

    2008-05-01

    Full Text Available This paper summarizes our research work regarding the dynamics of vegetation growth of miscellaneous species of trees planted and monitored in the particular environment of the tailing pond in Bozanta Mare (Maramures County. The structure of soil bearing high content of heavy metals and cyanides considerably impacts the ecologic conditions of tailing ponds. Aspects related to soil characteristics (such as structure, size of particles, porosity, texture, chemical composition are included. Vegetal species that have accommodated within the tail pond are included as well. In the framework of our experiment we have planted seedlings belonging to four species of trees: Quercus petraea, Populus tremula, Betula verrucosa, Salix caprea. We have planted the seedlings in different location contexts in the tailing pond (“in situ”, as we have also planted “ex situ” witness trees. Our aim was to monitor the dynamics of growth of the stem and of cuttings. Our contribution, based on the outcomes of our research, consists in the formulation of functional correlations spotted between cormophites and micro biota, between the species of trees and their environmental underlying conditions, with the overarching goal to optimize the activities undertaken in order to alleviate the tailing ponds inherent to mining activities.

  11. ALPINE VEGETATION ECOTONE DYNAMICS IN GANGOTRI CATCHMENT USING REMOTE SENSING TECHNIQUES

    Directory of Open Access Journals (Sweden)

    C. P. Singh

    2012-09-01

    Full Text Available Analysis of the satellite imagery reveals two different perspectives of the vegetation ecotone dynamics in Gangotri catchment. On one hand, there is evidence of upward shift in the alpine tree and vegetation ecotone over three decades. On the other hand, there has been densification happening at the past treeline. The time series fAPAR data of two decades from NOAA-AVHRR confirms the greening trend in the area. The density of trees in Chirbasa has gone up whereas in Bhojbasa there is no significant change in NDVI but the number of groves has increased. Near Gaumukh the vegetal activity has not shown any significant change. We found that the treeline extracted from satellite imagery has moved up about 327±80m and other vegetation line has moved up about 401±77m in three decades. The vertical rate of treeline shift is found to be 11m/yr with reference to 1976 treeline; however, this can be 5m/yr if past toposheet records (1924 – 45 are considered as reliable reference. However, the future IPCC scenario based bioclimatic fundamental niche modelling of the Betula utilis (a surrogate to alpine treeline suggests that treeline could be moving upward with an average rate of 3m/yr. This study not only confirms that there is an upward shift of vegetation in the alpine zone of Himalayas, but also indicate that old vegetation ecotones have grown denser

  12. Characteristic of Tuber spp. localities in natural stands with emphasis on plant species composition

    Directory of Open Access Journals (Sweden)

    Dorota Hilszczanska

    2014-12-01

    Full Text Available Fungi belonging to the genus Tuber establish ectomycorrhizal symbioses with shrubs, trees and some herbaceous plants. Some Tuber species, for example, T. melanosporum, T. magnatum, T. aestivum are economically important because they produce edible fruiting bodies with a distinctive taste and flavor. Our concept of truffle ecophysiology is dominated by the symbiosis with deciduous hosts, such as: Quercus spp., Fagus sylvatica, Castanea sativa, Corylus spp., Carpinus betulus, Ostrya carpinifolia, Betula verrucosa, and Tilia spp., whereas the real range of hosts in nature seems to be much wider. Moreover, interactions between Tuber mycelium and plant community could be more complex than just forming the ectomycorrhizal symbiosis. Here we show our inventory of plants and soils at six truffle’ sites in the southern part of Poland (Nida Basin and Przedbórz Upland. The aim of this study was to widen our understanding of ecological factors affecting Tuber spp., in the context of pioneering stage of research on truffles in Poland. We hope our findings will have a practical application and will help to choose suitable soils for truffle orchards.

  13. A geochemical study of toxic metal translocation in an urban brownfield wetland

    International Nuclear Information System (INIS)

    Rhizosphere soil and dominant plant samples were collected at a brownfield site in New Jersey, USA, during summer 2005 to evaluate plant metal uptake from the contaminated soils. Metal concentrations varied from 4.25 to 978 μg g−1 for As, 9.68–209 μg g−1 for Cr, 23.9–1870 μg g−1 for Cu, and 24.8–6502 μg g−1 for Zn. A wide range of metal uptake efficiencies in the roots, stems and leaves was found in this study. Data showed that (1) Betula populifolia has high Zn, Cu and As accumulations in the root, and high concentrations of Cu and Zn in the stem and the leaf; (2) Rhus copallinum has high accumulation of Zn and Cr in the leaf and Cu in the stem; (3) Polygonum cuspidatum has high accumulations of Cu and As in the root; and (4) Artemisia vulgaris shows high Cu accumulation in the leaf and the stem. - Highlights: ► Rhizosphere soil and dominant plant samples were studied at a brownfield. ► Plant roots showed exceptional capacity of heavy metal accumulation. ► Metal uptake efficiency decrease with the increases of pH and organic matter. ► Variations in metal uptake efficiency in the root, stem and leave were found. - Metal uptake by brownfield wetland plants in the New York/New Jersey metropolitan area.

  14. Co-occurrence of airborne allergenic pollen grains and fungal spores in Rzeszów, Poland (2000-2002

    Directory of Open Access Journals (Sweden)

    Idalia Kasprzyk

    2012-12-01

    Full Text Available The co-occurrence of airborne allergenic pollen grains and fungal spores was estimated in Rzeszów in the years 2000-2002. The volumetric method was used in this aerobiological study. Six taxa of pollen grains and five types of fungal spores characterized by strong allergenicity and/or high concentrations in the air were analyzed. The time series of pollen grains and fungal spores were compared using PCA analysis. The periods of the greatest concentrations of tree pollen did not coincide with similar periods for herbaceous plants and fungal spores. From February to mid-March, Alnus pollen dominated in the air. The second period was characterized by Betula pollen. It occurred in April. Herbaceous pollen and fungal spores occurred in the air simultaneously (from mid May to the end of August, creating a risky situation for sensitized people. The periods of the highest concentrations of Epicoccum and Ganoderma fungal spores did not coincide with the same period for the examined plant taxa. In Rzeszów the probability of becoming exposed to very high concentrations of allergenic pollen and fungal spores at the same time was high, especially in July, when the highest concentrations of Poaceae, Alternaria and Cladosporium were noted. The hypersensitivity to only one plant or fungal allergen is rarely encountered. Under the present scenarios of global warming, pollen seasons of many taxa will be longer and sufferers will have year-long symptoms.

  15. Analysis of airborne pollen concentrations in Zagreb, Croatia, 2002.

    Science.gov (United States)

    Peternel, Renata; Culig, Josip; Mitić, Bozena; Vukusić, Ivan; Sostar, Zvonimir

    2003-01-01

    Employing the volumetric method by use of a Hirst sampler, a total of 71,286 pollen grains, as many as 94.20% of them allergenic, were recorded in the air samples from the city of Zagreb during the 2002 pollen season. Among identified pollen of 35 plant species/genera/families, 23 were allergenic: Taxus/Juniperus, Alnus sp., Fraxinus sp., Betula sp., Corylus sp., Poaceae, Urticaceae, Artemisia sp., Ambrosia sp., Carpinus sp., Castanea sp., Chenopodiaceae, Salix sp., Populus sp., Ulmus sp., Juglans sp., Quercus sp., Platanus sp., Fagus sp., Plantago sp., Pinus sp., Picea sp. and Abies sp. The pollen of these plants also cause the majority of pollinosis in Europe. Study results and the pollen calendar designed for the 2002 pollen season for the City of Zagreb provide useful data for allergologists to reach an accurate diagnosis. The calendar also provides timely information on airborne pollen types and air concentrations for individuals with pollen hypersensitivity, thus allowing them to adjust their daily activities so as to minimize their contact with allergens and improve their quality of life both at home and at work. PMID:12852741

  16. The importance of the stationary and individual pollen monitoring for the diagnostic of pollen allergy

    Directory of Open Access Journals (Sweden)

    Dorota Myszkowska

    2012-12-01

    Full Text Available The aim of the study was to evaluate pollen seasons of selected taxa with particular reference to allergic taxa such as birch (Betula sp., grasses (Poaceae, mugwort (Artemisia sp. in Cracow in 2003 and 2004 (project number 3 PO5D 034 24 funded by the State Committee for Scientific Research. Pollen concentrations obtained using the stationary Burkard trap and personal Partrap FA 52 were compared. The volumetric method was used in the study. Average daily concentrations (pollen grains × m-3 were obtained by counting pollen grains every hour along 4 longitudinal transects and applying an appropriate conversion factor. Duration of the pollen season was determined using the 95% method. Variations in annual totals of pollen grains (birch and mugwort, in start dates (especially for grasses and in the season duration (birch and grasses were found. The comparison of pollen concentrations obtained using the stationary and personal traps at the same place showed non statistically significant correlation for all the studied taxa and statistically significant correlations for birch, mugwort and grasses (Spearman rank correlation. However, the statistically significant differences between the concentrations obtained using Burkard and Partrap carried by patients (Wilcoxon's test were noted. Very low concentrations of pollen grains measured indoor (work, flats and the influence of the local plants growing in separate place (courtyard of the Allergology Department on the pollen concentration were found.

  17. Molecular characterization of recombinant T1, a non-allergenic periwinkle (Catharanthus roseus) protein, with sequence similarity to the Bet v 1 plant allergen family.

    Science.gov (United States)

    Laffer, Sylvia; Hamdi, Said; Lupinek, Christian; Sperr, Wolfgang R; Valent, Peter; Verdino, Petra; Keller, Walter; Grote, Monika; Hoffmann-Sommergruber, Karin; Scheiner, Otto; Kraft, Dietrich; Rideau, Marc; Valenta, Rudolf

    2003-01-01

    More than 25% of the population suffer from Type I allergy, an IgE-mediated hypersensitivity disease. Allergens with homology to the major birch ( Betula verrucosa ) pollen allergen, Bet v 1, belong to the most potent elicitors of IgE-mediated allergies. T1, a cytokinin-inducible cytoplasmic periwinkle ( Catharanthus roseus ) protein, with significant sequence similarity to members of the Bet v 1 plant allergen family, was expressed in Escherichia coli. Recombinant T1 (rT1) did not react with IgE antibodies from allergic patients, and failed to induce basophil histamine release and immediate-type skin reactions in Bet v 1-allergic patients. Antibodies raised against purified rT1 could be used for in situ localization of natural T1 by immunogold electron microscopy, but did not cross-react with most of the Bet v 1-related allergens. CD analysis showed significant differences regarding secondary structure and thermal denaturation behaviour between rT1 and recombinant Bet v 1, suggesting that these structural differences are responsible for the different allergenicity of the proteins. T1 represents a non-allergenic member of the Bet v 1 family that may be used to study structural requirements of allergenicity and to engineer hypo-allergenic plants by replacing Bet v 1-related allergens for primary prevention of allergy. PMID:12656672

  18. The efficacy of six elite isolates of the fungus Chondrostereum purpureum against the sprouting of European aspen.

    Science.gov (United States)

    Hamberg, Leena; Hantula, Jarkko

    2016-04-15

    The sprouting of broad-leaved trees after cutting is problematic in forest regeneration areas, along roads and railways, under electric power and above gas pipe lines. In Finland, one of the most difficult species to control in these areas is the European aspen (Populus tremula), which produces both stump sprouts and root suckers after saplings have been cut. In this study, we investigated whether a decay fungus of broad-leaved trees, Chondrostereum purpureum, could be used as a biological control agent against aspen sprouting. The efficacy of six elite strains of C. purpureum (improved earlier in a breeding process) was investigated on aspen for three years. The most efficient C. purpureum strain, R53, tested earlier on birch (Betula pendula and B. pubescens), was efficient in causing mortality of aspen stumps and preventing the development of root suckers. With this strain, stump mortality was 78%, while significantly lower in control stumps which were cut only (47%). Aspen trees in the vicinity of the treatments (within a 10 m radius around each sapling) decreased the efficacy of C. purpureum. This study shows that the decay fungus C. purpureum can successfully be used in the sprout control of aspen saplings. PMID:26899306

  19. Trees are important conduits for emission of methane from temperate and tropical wetlands

    Science.gov (United States)

    Gauci, Vincent; Pangala, Sunitha; Gowing, David; Hornibrook, Edward

    2013-04-01

    Methane produced in wetland soil generally is thought to be emitted to the atmosphere primarily via diffusion through pore water, release of gas bubbles (i.e., ebullition), and gas phase diffusion through the aerenchyma of herbaceous plants. The role of trees as a conduit for methane export from soil to the atmosphere has received limited attention despite evidence from mesocosm experiments showing that seedlings and saplings of wetland trees have a significant capacity to transport soil-produced gases. Notably ~60% of global wetlands are forested. We present in situ measurements of methane flux from a temperate carr (swamp) composed of alder (Alnus glutinosa) and birch (Betula pubescens) situated in the United Kingdom and a tropical forested peat swamp located in Borneo. The in situ data are complemented by a mesocosm experiment in which methane emissions were measured from alder saplings subjected to two water-regime treatments. In both the in situ and mesocosm studies, emissions from trees are compared to methane flux from the ground surface, the latter occurring via pore water diffusion, ebullition or the aerenchyma of herbaceous plants. We show that tree stem emissions are controlled by a number of factors including tree species, soil pore-water concentration and stem lenticel density. Our results demonstrate that the omission of tree-mediated methane fluxes from measurement campaigns conducted in forested wetland can significantly underestimate total ecosystem flux of methane.

  20. Wood properties of trembling aspen and paper birch after 5 years of exposure to elevated concentrations of CO(2) and O(3).

    Science.gov (United States)

    Kostiainen, Katri; Kaakinen, Seija; Warsta, Elina; Kubiske, Mark E; Nelson, Neil D; Sober, Jaak; Karnosky, David F; Saranpää, Pekka; Vapaavuori, Elina

    2008-05-01

    We investigated the interactive effects of elevated concentrations of carbon dioxide ([CO(2)]) and ozone ([O(3)]) on radial growth, wood chemistry and structure of five 5-year-old trembling aspen (Populus tremuloides Michx.) clones and the wood chemistry of paper birch (Betula papyrifera Marsh.). Material for the study was collected from the Aspen FACE (free-air CO(2) enrichment) experiment in Rhinelander, WI, where the saplings had been exposed to four treatments: control, elevated [CO(2)] (560 ppm), elevated [O(3)] (1.5 x ambient) and their combination for five growing seasons. Wood properties of both species were altered in response to exposure to the treatments. In aspen, elevated [CO(2)] decreased uronic acids (constituents of, e.g., hemicellulose) and tended to increase stem diameter. In response to elevated [O(3)] exposure, acid-soluble lignin concentration decreased and vessel lumen diameter tended to decrease. Elevated [O(3)] increased the concentration of acetone-soluble extractives in paper birch, but tended to decrease the concentration of these compounds in aspen. In paper birch, elevated [CO(2)] decreased and elevated [O(3)] increased starch concentration. The responses of wood properties to 5 years of fumigation differed from those previously reported after 3 years of fumigation. PMID:18316312

  1. Tree species composition affects the abundance of rowan (Sorbus aucuparia L.) in urban forests in Finland.

    Science.gov (United States)

    Hamberg, Leena; Lehvävirta, Susanna; Kotze, D Johan; Heikkinen, Juha

    2015-03-15

    Recent studies have shown a considerable increase in the abundance of rowan (Sorbus aucuparia) saplings in urban forests in Finland, yet the reasons for this increase are not well understood. Here we investigated whether canopy cover or tree species composition, i.e., the basal areas of different tree species in Norway spruce dominated urban forests, affects the abundances of rowan seedlings, saplings and trees. Altogether 24 urban forest patches were investigated. We sampled the number of rowan and other saplings, and calculated the basal areas of trees. We showed that rowan abundance was affected by tree species composition. The basal area of rowan trees (≥ 5 cm in diameter at breast height, dbh) decreased with increasing basal area of Norway spruce, while the cover of rowan seedlings increased with an increase in Norway spruce basal area. However, a decrease in the abundance of birch (Betula pendula) and an increase in the broad-leaved tree group (Acer platanoides, Alnus glutinosa, Alnus incana, Amelanchier spicata, Prunus padus, Quercus robur, Rhamnus frangula and Salix caprea) coincided with a decreasing number of rowans. Furthermore, rowan saplings were scarce in the vicinity of mature rowan trees. Although it seems that tree species composition has an effect on rowan, the relationship between rowan saplings and mature trees is complex, and therefore we conclude that regulating tree species composition is not an easy way to keep rowan thickets under control in urban forests in Finland. PMID:25588119

  2. Ontogeny and environment as determinants of the secondary chemistry of three species of white birch.

    Science.gov (United States)

    Laitinen, Jaana; Julkunen-Tiitto, Riitta; Rousi, Matti; Heinonen, Jaakko; Tahvanainen, Jorma

    2005-10-01

    This study investigates variation in the secondary chemistry of the bark of three closely related, winter-dormant species of white birch (Betula resinifera, B. pendula, and B. platyphylla) at different ontogenetic stages by using different plant parts (top and base). The experimental birches were grown for 4 years in two growing conditions (pot and field) at different nutrient levels. There was considerable species-specific quantitative and qualitative variation in the secondary chemicals in bark, but this was also affected by fertilization and the age of the plant. In general, there was greater chemical diversity in saplings than in seedlings. The study revealed three new components, secoisolariciresinol 9-O-beta-glucopyranoside and two of its derivatives, that have not been reported previously for the bark of white birches. Principal component analysis showed that the species studied had a similar chemical composition at the juvenile stage, but as the plants grew, they became more clearly differentiated, which indicates that the species of older plants can be identified by chemotaxonomy. Evidently, the secondary chemistry of birches is under genetic control, but it is affected by properties of growing conditions and ontogeny. PMID:16195842

  3. Methane Emission through Trees in Temperate and Tropical Wetlands

    Science.gov (United States)

    Pangala, S. R.; Gauci, V.; Hornibrook, E. R.; Gowing, D.

    2012-12-01

    Methane produced in wetland soil generally is thought to be emitted by a combination of three key processes: 1) diffusion through water-filled pores, 2) abrupt release of bubbles (ebullition), and 3) via internal spaces within the stems of herbaceous plants adapted to live in waterlogged soils. The capacity for trees to mediate methane emissions has received limited attention despite mesocosm studies of seedlings and saplings demonstrating that wetland trees have a significant capacity to transport soil-produced methane to the atmosphere. Notably ~60% of global wetlands are forested. We present in situ measurements of methane flux from a temperate carr (swamp) composed of alder (Alnus glutinosa) and birch (Betula pubescens) situated in the United Kingdom and a tropical forested peat swamp located in Borneo. The in situ data are complemented by a mesocosm experiment in which methane emissions were measured from alder saplings subjected to two water-regime treatments. In both the in situ and mesocosm studies, emissions from trees are compared to methane flux from the ground surface, the latter occurring via pore water diffusion, ebullition or via the aerenchyma of herbaceous plants. We show that tree stem emissions are controlled by a number of factors including tree species, soil pore-water concentration and stem lenticel density. Our results demonstrate that the omission of tree-mediated methane fluxes from measurement campaigns conducted in forested wetland can significantly underestimate the total ecosystem flux of methane.

  4. The effect of fire disturbance on short-term soil respiration in typical forest of Greater Xing’an Range, China

    Institute of Scientific and Technical Information of China (English)

    Long Sun; Tongxin Hu; Ji Hong Kim; Futao Guo; Hong Song; Xinshuang Lv; Haiqing Hu

    2014-01-01

    We investigated the effect of fire disturbance on short-term soil respiration in birch (Betula platyphylla Suk.) and larch (Larix gmelinii Rupr.) forests in Greater Xing’an range, northeastern China for further understanding of its effect on the carbon cycle in ecosystems. Our study show that post-fire soil respiration rates in B. platyphylla and L. gmelinii forests were reduced by 14%and 10%, respectively. In contrast, the soil heterotrophic respiration rates in the two types of forest were similar in post-fire and control plots. After fire, the contribution of root respiration to total soil respiration was dramatically reduced. Variation in soil respiration rates was explained by soil moisture (W) and soil tem-perature (T) at a depth of 5 cm. Exponential regression fitted T and W models explained Rs rates in B. platyphylla control and post-fire plots (83.1% and 86.2%) and L. gmelinii control and post-fire plots (83.7%and 88.7%). In addition, the short-term temperature coefficients in B.

  5. The effect of increased air humidity on fine root and rhizome biomass and turnover of silver birch forest ecosystem - a FAHM study.

    Science.gov (United States)

    Ostonen, I.; Kupper, P.; Sõber, J.; Aosaar, J.; Varik, M.; Lõhmus, K.

    2012-04-01

    A facility for free air humidity manipulation (FAHM) was established to investigate the effect of increased air humidity on belowground biomass and turnover in silver birch (Betula pendula Roth.) forest ecosystems with respect to rising air humidity predicted for Northern Europe. Fine root and rhizomes are short-lived and recognized as the most important component contributing to below-ground C fluxes in forests. The FAHM system enables air relative humidity to be increased on average 7 units (%) over the ambient level during mist fumigation. The experimental site contains humidified (H) and control (C) plots; each plot contains sectors with diverse "forest" understory and early successional grasses. The trees were planted in 2006, humidification started in spring 2008, and soil cores to study fine root and rhizome biomass and turnover were taken in 2007, 2009 and 2010. In July 2009, total fine root and rhizome biomass was 8 tons per ha in C and 16 tons per ha in H plots. The roots of understory formed 86% in C and 93% H plots, respectively. Our preliminary data suggest that the increased humidity affected more the roots of understory plants: fine root and rhizome biomass and production increased approximately twice by increasing air humidity. However, the tendency was similar for fine root biomass and production of silver birch. Fine root turnover speeded up for both silver birch and understory roots in H plots. Hence, changes in air humidity can significantly affect forest carbon cycling.

  6. Pulse Pressure magnifies the effect of COMTVal158Met on 15 Year Episodic Memory Trajectories

    Directory of Open Access Journals (Sweden)

    Ninni ePersson

    2016-03-01

    Full Text Available We investigated whether a physiological marker of cardiovascular health, pulse pres­sure (PP, and age magnified the effect of the functional COMT Val158Met (rs4680 pol­ymor­phism on 15-year cognitive trajectories (episodic memory [EM], visuospatial ability, and se­man­tic memory using data from 1585 non-demented adults from the Betula study. A mul­tiple-group growth model was specified to gauge individual differences in change. The allelic variants showed negligible differences across the cognitive markers in average trends. The older portion of the sample selectively age-magnified the effects of Val158Met on EM changes, resulting in greater decline in Val compared to homozygote Met carriers. This effect was attenuated by sta­tistical control for PP. Further, PP mod­erated the effects of COMT on 15-year EM trajectories, resulting in greater decline in Val carriers, even after accounting for the confounding effects of sex, education, cardiovascular diseases (dia­betes, stroke, and hypertension, and chronological age, controlled for practice gains. The effect was still present after excluding individuals with a history of cardiovascular diseases. The effects of cognitive change were not moderated by any other covariates. This report underscores the importance of addressing synergistic effects in nor­mal cognitive aging, as the addition thereof may even place healthy individuals at greater risk for memory decline.

  7. Genome-scale transcriptome analysis in response to nitric oxide in birch cells: implications of the triterpene biosynthetic pathway.

    Directory of Open Access Journals (Sweden)

    Fansuo Zeng

    Full Text Available Evidence supporting nitric oxide (NO as a mediator of plant biochemistry continues to grow, but its functions at the molecular level remains poorly understood and, in some cases, controversial. To study the role of NO at the transcriptional level in Betula platyphylla cells, we conducted a genome-scale transcriptome analysis of these cells. The transcriptome of untreated birch cells and those treated by sodium nitroprusside (SNP were analyzed using the Solexa sequencing. Data were collected by sequencing cDNA libraries of birch cells, which had a long period to adapt to the suspension culture conditions before SNP-treated cells and untreated cells were sampled. Among the 34,100 UniGenes detected, BLASTX search revealed that 20,631 genes showed significant (E-values≤10-5 sequence similarity with proteins from the NR-database. Numerous expressed sequence tags (i.e., 1374 were identified as differentially expressed between the 12 h SNP-treated cells and control cells samples: 403 up-regulated and 971 down-regulated. From this, we specifically examined a core set of NO-related transcripts. The altered expression levels of several transcripts, as determined by transcriptome analysis, was confirmed by qRT-PCR. The results of transcriptome analysis, gene expression quantification, the content of triterpenoid and activities of defensive enzymes elucidated NO has a significant effect on many processes including triterpenoid production, carbohydrate metabolism and cell wall biosynthesis.

  8. Non-destructive methods for peat layer assessment in oligotrophic peat bogs: a case study from Poiana Ştampei, Romania

    Directory of Open Access Journals (Sweden)

    Iuliana F. Gheorghe

    2011-04-01

    Full Text Available Practices currently employed in the investigation and characterisation of peat deposits are destructive and may irremediable perturb peat bog development even in cases when exploitation is not carried out. We investigated the correlation between vegetation characteristics in the active area of Poiana Ştampei peat bog, Romania, and the underlying peat layer depth, aiming at establishing a non-destructive method of peat layer depth estimation. The presence of the Sphagneto-Eriophoretum vaginati association, dominated by Sphagnum fimbriatum, Eriophorum vaginatum, Andromeda polifolia, Vaccinium oxycoccos, V. myrtillus, V. vitis-idaea, Polytrichum commune, Picea excelsa, Pinus sylvestris and Betula verrucosa was found to predict the existence of the peat layer but not its depth. Out of the seven identified vegetation types, one type was associated with a very thin or no peat layer, one type was characterised by the presence of a thick (over 100 cm peat layer and five types indicated the presence of variable average depths of the peat layer. pH values correlated with peat layer depth only within the vegetation type associated with thick peat layers.

  9. Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

    Science.gov (United States)

    Jia, Guodong; Yu, Xinxiao; Fan, Dengxing; Jia, Jianbo

    2016-01-01

    Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r) functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono) and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined. PMID:27028757

  10. Birch Stands Growth Increase in Western Siberia

    Science.gov (United States)

    Kharuk, Viacheslav I.; Kuzmichev, Valeriy V.; Im, Sergey T.; Ranson, Kenneth J.

    2014-01-01

    Birch (Betula pendula Roth) growth within the Western Siberia forest-steppe was analyzed based on long-term (1897-2006) inventory data (height, diameter at breast height [dbh], and stand volume). Analysis of biometry parameters showed increased growth at the beginning of twenty-first century compared to similar stands (stands age = 40-60 years) at the end of nineteenth century. Mean height, dbh, and stem volume increased from 14 to 20 m, from 16 to 22 cm, and from approx. 63 to approx. 220 cu m/ha, respectively. Significant correlations were found between the stands mean height, dbh, and volume on the one hand, and vegetation period length (r(sub s) = 0.71 to 0.74), atmospheric CO2 concentration (r(sub s) = 0.71 to 0.76), and drought index (Standardized Precipitation-Evapotranspiration Index, r(sub s) = -0.33 to -0.51) on the other hand. The results obtained have revealed apparent climate-induced impacts (e.g. increase of vegetation period length and birch habitat drying due to drought increase) on the stands growth. Along with this, a high correlation of birch biometric parameters and [CO2] in ambient air indicated an effect of CO2 fertilization. Meanwhile, further drought increase may switch birch stand growth into decline and greater mortality as has already been observed within the Trans-Baikal forest-steppe ecotone.

  11. Forest biomass at Xiaolong Mountain in Gansu Province,China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to accurately estimate the size of the carbon pool and the capacity of the carbon sink in the forested areas of Xiaolong Mountain in Gansu Province,we have established regression equations of organ biomass of eight tree species.We measured and investigated the biomass of different forest stand types based on data from 1259 standard sample plots and 836 standard sample trees.for eight types of forest stands on Xiaolong Mountain,are as follows:Quercus aliena var.acuteserrata 84.05,Pinus tabulaeformis 62.44,Quercus variabilis 81.77,Populus sp.and Betula sp.combined 77.44,Larix sp.69.00,Pinus armandii 70.07,Picea sp.96.49 and Abies sp.98.72.We also looked at other broad-leaved mixed forests.Our study shows that the biomass of a single tree of each tree species is closely related to the diameter at breast height (DBH) and to tree height.The biomass of single trees as well as stand volumes is closely related to average DBH,average tree height and to stand density.

  12. The sedimentary sequence from the Lake Ķūži outcrop, central Latvia: implications for late glacial stratigraphy

    Directory of Open Access Journals (Sweden)

    Tiiu Koff

    2011-06-01

    Full Text Available Sediment samples from an outcrop in the near-shore area of Lake Ķūži (Vidzeme Heights, Central Latvia were investigated using palaeobotanical (pollen and macrofossil analysis and lithological (grain-size analysis methods and accelerator mass spectrometry 14C dating. A dark, organic-rich sediment layer was found below 1.7 m of sandy layers approximately 30 cm above the present lake level. Radiocarbon dating of a wood sample from the lowermost layer (11 050 ± 60 14C BP, 13 107–12 721 cal BP shows that the layer is of late glacial age. The composition of the pollen spectra is characterized by Betula nana, Cyperaceae pollen and spores of Equisetum, confirming that the lowermost sediments were formed during the late glacial. Fossils of obligate aquatic organisms in the upper layer, which include oospores of Characeae and seeds of Potamogeton, indicate an open water environment. Pollen of Myriophyllum and Potamogeton and non-pollen palynomorphs, such as algal Botryococcus and Pediastrum cf. boryanum, confirm this conclusion. The pollen assemblage from the greyish loam layer following this lacustrine phase shows a pattern characteristic of the Younger Dryas vegetation before the start of the real expansion of birch forests at the beginning of the Holocene.

  13. Holocene Vegetation and Climate History on the Zoige Plateau in the Eastern Tibetan Plateau

    Science.gov (United States)

    Zhao, Y.; Yu, Z.; Chen, F.; Zhao, W.

    2009-12-01

    We present a well-dated and high-resolution fossil pollen record and discuss its climatic interpretations from a peatland in Zoige on the Eastern Tibetan Plateau. The objectives of this study were to provide a detailed reconstruction of regional vegetation history during the Holocene and to understand the vegetation response to Asian summer monsoon. The 10,300-year chronology of the 650-cm-long peat core (ZB08-c1) was controlled by eight AMS C-14 dates on hand-picked charcoals. Loss-on-ignition (LOI) analysis was conducted at 1-cm intervals, and pollen analysis at mostly 8-cm intervals. LOI results indicate that organic matter content is high at 60-80% between ~10,000 and 4000 cal BP, but decreases to Cyperaceae (60-80%), Picea (up to 15%), Ranunculaceae (up to 10%) and Betula, indicating Cyperaceae-dominated vegetation on peatlands and Picea-dominated upland vegetation. Total tree pollen has high values (up to 35%) during the early and mid-Holocene, but decreases after 4000 cal yr BP. The tree pollen decline from ~4000 to 2500 cal BP likely reflects the deforestation caused by weakened summer monsoon, as similar forest decline has been documented at other sites on the northeastern Tibetan Plateau. However, vegetation and lithology changes since 2500 cal BP, especially after 1300 cal BP, were likely caused by human-induced deforestation, pasture grazing and resultant erosion, which has been documented in other peat-based studies from the region.

  14. Dynamic early Holocene vegetation development on the Faroe Islands inferred from high-resolution plant macrofossil and pollen data

    Science.gov (United States)

    Hannon, Gina E.; Rundgren, Mats; Jessen, Catherine A.

    2010-03-01

    Vegetation dynamics during the earliest part of the Holocene (11,250-10,250 cal yr BP) have been reconstructed from a lacustrine sequence on Sandoy, the Faroe Islands, using detailed plant macrofossil and pollen evidence. The plant macrofossils suggest the initial vegetation was sparse herb and shrub tundra, with Salix herbacea and open-ground species, followed by the development of a denser and more species-rich arctic heathland after 11,150 cal yr BP. Despite high pollen values for Betula nana, macrofossils are rare. The bulk of the macrofossils recorded are S. herbacea and Empetrum leaves with numerous herb taxa and an abundance of Racomitrium moss. Conditions start to change around 10,800 cal yr BP, with increased catchment erosion and sediment delivery to the lake from ca. 10,600 cal yr BP, and a transition to alternating Cyperaceae and Poaceae communities between ca. 10,450 and 10,250 cal yr BP. This vegetation change, which has been recorded throughout the Faroes, has previously been interpreted as a retrogressive shift from woody shrubs to a herbaceous community. The detailed plant macrofossil data show the shift is the replacement of an Empetrum arctic heathland by grassland and moist sedge communities. These taxa dominate the modern landscape.

  15. Surface pollen and its relationship to vegetation in the Zoige Basin, eastern Tibetan Plateau

    Science.gov (United States)

    Li, Furong; Zhao, Yan; Sun, Jinghui; Zhao, Wenwei; Guo, Xiaoli; Zhang, Ke

    2011-09-01

    We use a data set of 23 surface pollen samples from moss polsters in the Zoige Basin to explore the relationship between modern pollen assemblages and contemporary vegetation patterns. The surface pollen samples spanned four types of plant communities: Carex muliensis marsh, Stipa and Kobresia meadow, Carex-dominated forb meadow and Sibiraea angustata scrub. Principal-components analysis (PCA) was used to determine the relationships between modern pollen and vegetation and environmental variables. The results show that the pollen assemblages of surface moss samples generally reflect the features of the modern vegetation, basically similar in the vegetation types and the dominant genera; however, they don't show a very clear distinction between different communities. Our results also demonstrate that pollen representation of different families or genus varied. Some tree taxa, such as Pinus and Betula, and herb types, such as Artemisia are over-represented, while Asteraceae, Ranunculaceae and Cyperaceae are moderately represented, and Poaceae and Rosaceae are usually under-represented in our study region. PCA results indicate that the distribution of vegetation in the Zoige Basin is mainly controlled by precipitation and altitude.

  16. Altered vegetative assemblage trajectories within an urban brownfield

    International Nuclear Information System (INIS)

    Recognizing the growing importance of both structure (maintenance of biodiversity) and function (fostering natural cycles) of urban ecologies, we examine coarse scale (herbaceous, shrub and forest) beta guild trajectory in an urban brownfield. The distribution of the pioneer forest assemblage dominated by Betula populifolia Marsh. and Populus spp. could be correlated positively with total soil metal load (arsenic, cadmium, chromium, copper, lead, zinc, lead and vanadium),whereas herbaceous and shrub guilds were negatively correlated. Distinct assemblage development trajectories above and below a critical soil metal threshold are demonstrated. In addition, we postulate that the translocation of metals into the plant tissue of several dominant species may provide a positive feedback loop, maintaining relatively high concentrations of metals in the litter and soil. Therefore assembly theory, which allows for the development of alternate stable states, may provide a better model for the establishment of restoration objectives on degraded urban sites. - Highlights: → Forest distribution and total soil metal load yield strong positive correlations. → Shrub and herbaceous guild distribution and TML are negative and weaker. → Below a critical TML threshold transition between guilds exhibit a standard trajectory. → Above the critical TML threshold the shrub guild is virtually absent. → Metal cycling has the potential to lead to an alternative steady state. - High concentrationsof soil metals, impact the trajectory of vegetative assemblages in an urban brownfield leading to the speculation of an alternate stable state.

  17. Late Glacial and Early Holocene Climatic Changes Based on a Multiproxy Lacustrine Sediment Record from Northeast Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Kokorowski, H D; Anderson, P M; Sletten, R S; Lozhkin, A V; Brown, T A

    2008-05-20

    Palynological (species assemblage, pollen accumulation rate), geochemical (carbon to nitrogen ratios, organic carbon and biogenic silica content), and sedimentological (particle size, magnetic susceptibility) data combined with improved chronology and greater sampling resolution from a new core from Elikchan 4 Lake provide a stronger basis for defining paleoenvironmental changes than was previously possible. Persistence of herb-dominated tundra, slow expansion of Betula and Alnus shrubs, and low percentages of organic carbon and biogenic silica suggest that the Late-Glacial transition (ca. 16,000-11,000 cal. yr BP) was a period of gradual rather than abrupt vegetation and climatic change. Consistency of all Late-Glacial data indicates no Younger Dryas climatic oscillation. A dramatic peak in pollen accumulation rates (ca. 11,000-9800 cal. yr BP) suggests a possible summer temperature optimum, but finer grain-sizes, low magnetic susceptibility, and greater organic carbon and biogenic silica, while showing significant warming at ca. 11,000 cal. yr BP, offer no evidence of a Holocene thermal maximum. When compared to trends in other paleo-records, the new Elikchan data underscore the apparent spatial complexity of climatic responses in Northeast Siberia to global forcings between ca. 16,000-9000 cal. yr BP.

  18. Floodplain forest loss and changes in forest community composition and structure in the upper Mississippi River: a wildlife habitat at risk

    Science.gov (United States)

    Knutson, M.G.; Klaas, E.E.

    1998-01-01

    Large floodplain forests represent a threatened and endangered type of ecosystem in the United States. Estimates of cumulative losses of floodplain forest range from 57% to 95% at different locations within the continental United Stales. Floodplain forests of the Upper Mississippi River (UMR) have significantly declined in extent due to agriculture, lock and dam construction, and urban development since European settlement. We collected data on shrubs, herbs, and trees from 56 floodplain forest plots in 1992 and compared our results with a previous analysis of historical tree data from the same area recorded by the General Land Office Survey in the 1840s. Acer saccharinum strongly dominates among mature trees and its relative dominance has increased over time. Salix spp. And Betula nigra have declined in relative dominance. Tree sizes are similar to those of presettlement forests, but present forests have fewer trees. The lack of early successional tree species and a trend toward an increasing monoculture of A. Saccharinum in the mature stages indicate problems with regeneration. Because floodplain forests represent a rare habitat type, losses and changes in habitat quality could pose serious problems for wildlife that depend upon these habitats, especially birds.

  19. Survey of microfungi in the Landschaftspark Duisburg-Nord (Germany).

    Science.gov (United States)

    Jensen, M; Nerat, N; Ale-Agha, N

    2011-01-01

    During an excursion in the Landschaftspark Duisburg-Nord in 2009 and 2010 we were able to collect and identify more than 100 specimens of microfungi on different parts of cultivated and wild plant species. We found parasitic and saprophytic microfungi on trees, bushes and herbaceous plants. Some of them have been observed only rarely until now. Most of the collected microfungi species belong to the classes of Ascomycetes, Basidiomycetes and Deuteromycetes - for example Leptosphaeria modesta (Desm.) Rabenh. on Knautia cf. arvensis (L.) Coult., Ramularia urticae Ces. on Urtica dioica L., Stigmina glomerulosa (Sacc.) S. Hughes on Juniperus communis L., Pseudomassaria corni (Sowerby) Arx on Cornus alba L., Mollisia discolor (Mont.) W. Phillips on Cornus alba L., Botryosphaeria quercuum (Schwein.) Sacc. on Quercus robur L., Peronospora cytisi Rostr. on Laburnum anagyroides Med., Microsphaera guarinonii Briosi and Cavara on Laburnum anagyroides Med., Brachysporium dingleyae S. Hughes on Fraxinus angustifolia Vahl and Rhododendron spec., Mamiania fimbriata (Pers.) Ces. and De Not. on Carpinus betulus L., Atopospora betulina (Fr.) Petr. on Betula pendula Roth, Septoria robiniae (Lib.) Desm. (=Phloeospora robiniae (Lib.) Höhn.) on Robinia pseudoacacia L., Chalara hughesii Nag Raj and W.B. Kendr. on Quercus robur L.. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige and N. Ale-Agha. PMID:22702187

  20. Elevated Atmospheric CO2 Affects Ectomycorrhizal Species Abundance and Increases Sporocarp Production under Field Conditions

    Directory of Open Access Journals (Sweden)

    Douglas L. Godbold

    2015-04-01

    Full Text Available Anthropogenic activities during the last century have increased levels of atmospheric CO2. Forest net primary productivity increases in response to elevated CO2, altering the quantity and quality of carbon supplied to the rhizosphere. Ectomycorrhizal fungi form obligate symbiotic associations with the fine roots of trees that mediate improved scavenging for nutrients in exchange for a carbohydrate supply. Understanding how the community structure of ectomycorrhizal fungi is altered by climate change is important to further our understanding of ecosystem function. Betula pendula and Fagus sylvatica were grown in an elevated CO2 atmosphere delivered using free air carbon dioxide enrichment (FACE under field conditions in the U.K., and Picea abies was grown under elevated CO2 in glass domes in the Czech Republic. We used morphotyping and sequencing of the internal transcribed spacer region of the fungal ribosomal operon to study ectomycorrhizal community structure. Under FACE, un-colonised roots tips increased in abundance for Fagus sylvatica, and during 2006, sporocarp biomass of Peziza badia significantly increased. In domes, ectomycorrhizal community composition shifted from short-distance and smooth medium-distance to contact exploration types. Supply and competition for carbon belowground can influence ectomycorrhizal community structure with the potential to alter ecosystem function.

  1. Pulse Pressure Magnifies the Effect of COMT Val(158)Met on 15 Years Episodic Memory Trajectories.

    Science.gov (United States)

    Persson, Ninni; Lavebratt, Catharina; Sundström, Anna; Fischer, Håkan

    2016-01-01

    We investigated whether a physiological marker of cardiovascular health, pulse pressure (PP), and age magnified the effect of the functional COMT Val(158)Met (rs4680) polymorphism on 15-years cognitive trajectories [episodic memory (EM), visuospatial ability, and semantic memory] using data from 1585 non-demented adults from the Betula study. A multiple-group latent growth curve model was specified to gauge individual differences in change, and average trends therein. The allelic variants showed negligible differences across the cognitive markers in average trends. The older portion of the sample selectively age-magnified the effects of Val(158)Met on EM changes, resulting in greater decline in Val compared to homozygote Met carriers. This effect was attenuated by statistical control for PP. Further, PP moderated the effects of COMT on 15-years EM trajectories, resulting in greater decline in Val carriers, even after accounting for the confounding effects of sex, education, cardiovascular diseases (diabetes, stroke, and hypertension), and chronological age, controlled for practice gains. The effect was still present after excluding individuals with a history of cardiovascular diseases. The effects of cognitive change were not moderated by any other covariates. This report underscores the importance of addressing synergistic effects in normal cognitive aging, as the addition thereof may place healthy individuals at greater risk for memory decline. PMID:26973509

  2. Pulse Pressure Magnifies the Effect of COMT Val158Met on 15 Years Episodic Memory Trajectories

    Science.gov (United States)

    Persson, Ninni; Lavebratt, Catharina; Sundström, Anna; Fischer, Håkan

    2016-01-01

    We investigated whether a physiological marker of cardiovascular health, pulse pressure (PP), and age magnified the effect of the functional COMT Val158Met (rs4680) polymorphism on 15-years cognitive trajectories [episodic memory (EM), visuospatial ability, and semantic memory] using data from 1585 non-demented adults from the Betula study. A multiple-group latent growth curve model was specified to gauge individual differences in change, and average trends therein. The allelic variants showed negligible differences across the cognitive markers in average trends. The older portion of the sample selectively age-magnified the effects of Val158Met on EM changes, resulting in greater decline in Val compared to homozygote Met carriers. This effect was attenuated by statistical control for PP. Further, PP moderated the effects of COMT on 15-years EM trajectories, resulting in greater decline in Val carriers, even after accounting for the confounding effects of sex, education, cardiovascular diseases (diabetes, stroke, and hypertension), and chronological age, controlled for practice gains. The effect was still present after excluding individuals with a history of cardiovascular diseases. The effects of cognitive change were not moderated by any other covariates. This report underscores the importance of addressing synergistic effects in normal cognitive aging, as the addition thereof may place healthy individuals at greater risk for memory decline. PMID:26973509

  3. Thermal Insulation from Hardwood Residues

    Science.gov (United States)

    Sable, I.; Grinfelds, U.; Vikele, L.; Rozenberga, L.; Zeps, M.; Luguza, S.

    2015-11-01

    Adequate heat is one of the prerequisites for human wellbeing; therefore, building insulation is required in places where the outside temperature is not suitable for living. The climate change, with its rising temperatures and longer dry periods, promotes enlargement of the regions with conditions more convenient for hardwood species than for softwood species. Birch (Betula pendula) is the most common hardwood species in Latvia. The aim of this work was to obtain birch fibres from wood residues of plywood production and to form low-density thermal insulation boards. Board formation and production was done in the presence of water; natural binder, fire retardant and fungicide were added in different concentrations. Board properties such as density, transportability or resistance to particulate loss, thermal conductivity and reaction to fire were investigated. This study included thermal insulation boards with the density of 102-120 kg/m3; a strong correlation between density and the binder amount was found. Transportability also improved with the addition of a binder, and 0.1-0.5% of the binder was the most appropriate amount for this purpose. The measured thermal conductivity was in the range of 0.040-0.043 W/(m·K). Fire resistance increased with adding the fire retardant. We concluded that birch fibres are applicable for thermal insulation board production, and it is possible to diversify board properties, changing the amount of different additives.

  4. Coupled long-term summer warming and deeper snow alters species composition and stimulates gross primary productivity in tussock tundra.

    Science.gov (United States)

    Leffler, A Joshua; Klein, Eric S; Oberbauer, Steven F; Welker, Jeffrey M

    2016-05-01

    Climate change is expected to increase summer temperature and winter precipitation throughout the Arctic. The long-term implications of these changes for plant species composition, plant function, and ecosystem processes are difficult to predict. We report on the influence of enhanced snow depth and warmer summer temperature following 20 years of an ITEX experimental manipulation at Toolik Lake, Alaska. Winter snow depth was increased using snow fences and warming was accomplished during summer using passive open-top chambers. One of the most important consequences of these experimental treatments was an increase in active layer depth and rate of thaw, which has led to deeper drainage and lower soil moisture content. Vegetation concomitantly shifted from a relatively wet system with high cover of the sedge Eriophorum vaginatum to a drier system, dominated by deciduous shrubs including Betula nana and Salix pulchra. At the individual plant level, we observed higher leaf nitrogen concentration associated with warmer temperatures and increased snow in S. pulchra and B. nana, but high leaf nitrogen concentration did not lead to higher rates of net photosynthesis. At the ecosystem level, we observed higher GPP and NEE in response to summer warming. Our results suggest that deeper snow has a cascading set of biophysical consequences that include a deeper active layer that leads to altered species composition, greater leaf nitrogen concentration, and higher ecosystem-level carbon uptake. PMID:26747269

  5. Landscape Mapping and Tree Diversity Assessment of Pangi Valley: A Remote Tribal Area of Himachal Pradesh in Western Himalaya, India

    Directory of Open Access Journals (Sweden)

    Amit KUMAR

    2013-12-01

    Full Text Available Pangi valley in Chamba district of Himachal Pradesh is one of the remote tribal areas in Indian western Himalaya. The plant resources in its landscapes are flourishing under least anthropogenic conditions. For social upliftment of the tribals in this area, a number of developmental activities are being implemented by the government. A study was conducted for mapping of its landuse/landcover using satellite remote sensing to identify major forested landscapes in the region. It was followed by a detailed random stratified sampling of the forested landscapes for phytosociological estimation of its tree species. The 21.97 % of study area was estimated under forests followed by Scrublands and Grassy meadows (18.24 %. Majority of area (54.05 % was Snow and Scree slopes. Among the forests, maximum area was occupied by Mixed Broad Leaved Forest LSE type (36.08% followed by Cedrus deodara (26.94% and Betula utilis (18.07% forest LSE types. These species, owing to immense medicinal properties and value for their economic utilization, feature in threatened and endangered category list of plants. It is, therefore, recommended that the developmental activities may be implemented in scientific way, which may not pose threat to bioresources in this region.

  6. Factors influencing caesium-137 levels in moose (Alces alces) and small game in Northern Sweden

    International Nuclear Information System (INIS)

    In the third annual hunting season after the Chernobyl accident the concentration of Cs-137 in meat of northern Swedish moose was significantly higher than in the first one (1986). In September 1986 the mean Cs concentration was 500 Bq/kg in calves but in September 1988 it has risen 1300 Bq/kg. This increase was only temporary and a rapid decline occured after September and by December 1988 the concentration of Cs was the same as in late 1986. Adult moose showed the same increase during the hunt 1988 but to a lower magnitude. Typical food plants of moose such as bilberry (Vaccinum myrtillus) and birch (Betula pubescens) showed, contradictory to expected by the level in moose, a decline of concentration caesium from 1986 to 1988. A probable explanation to the dramatically increased concentration of Cs in moose is a change in diet selection during 1988. Small mammals such as voles and lemmings showed a variation in concentration of caesium-137 which was more dependent on other factors than on their body size. This emphasize the necessity to study diet selection by herbivores in detail in order to predict uptake and changes in environmental contaminants. (orig.)

  7. Bioaccumulation of arsenic and cadmium in birch and lime from the Bor region.

    Science.gov (United States)

    Alagić, Slađana Č; Šerbula, Snežana S; Tošić, Snežana B; Pavlović, Aleksandra N; Petrović, Jelena V

    2013-11-01

    Copper production in the Bor region (east Serbia) during the last 100 years has influenced the quality of soil, water, and air. This pollution has endangered not only the biotope but all living organisms, including humans. Contents of arsenic (As) and cadmium (Cd) were analyzed in Betula sp. (birch) and Tillia sp. (lime) within the Bor region with the aim to investigate the bioaccumulation of these highly toxic, nonessential trace elements in selected plants, which may be important for biomonitoring and bioremediation purposes. The results of statistical data analysis showed that several factors influenced the bioaccumulation of trace elements in the examined plants, of which soil pH, soil content, and mechanism of accumulation were the main factors. The greatest As and Cd concentrations were found in plant material from the Bor center sampling site in the urban/industrial zone, which is in close proximity to the pollution source, due to the greatest metal concentrations in soil and the lowest soil pH. The low values of biological accumulation coefficients (bioconcentration factor mobility ratio <1) pointed to a low rate of uptake and accumulation of As and Cd in lime and birch. Trace elements showed different patterns of behavior and accumulation in the trees. Lime showed a high ability of assimilation through leaves, whereas birch showed a better potential to express a linear correlation between concentrations in plant parts and soil. PMID:23963120

  8. The role of forest floor and trees to the ecosystem scale methane budget of boreal forests

    Science.gov (United States)

    Pihlatie, Mari; Halmeenmäki, Elisa; Peltola, Olli; Haikarainen, Iikka; Heinonsalo, Jussi; Santalahti, Minna; Putkinen, Anuliina; Fritze, Hannu; Urban, Otmar; Machacova, Katerina

    2016-04-01

    Boreal forests are considered as a sink of atmospheric methane (CH4) due to the activity of CH4 oxidizing bacteria (methanotrophs) in the soil. This soil CH4 sink is especially strong for upland forest soils, whereas forests growing on organic soils may act as small sources due to the domination of CH4 production by methanogens in the anaerobic parts of the soil. The role of trees to the ecosystem-scale CH4 fluxes has until recently been neglected due to the perception that trees do not contribute to the CH4 exchange, and also due to difficulties in measuring the CH4 exchange from trees. Findings of aerobic CH4 formation in plants and emissions from tree-stems in temperate and tropical forests during the past decade demonstrate that our understanding of CH4 cycling in forest ecosystems is not complete. Especially the role of forest canopies still remain unresolved, and very little is known of CH4 fluxes from trees in boreal region. We measured the CH4 exchange of tree-stems and tree-canopies from pine (Pinus sylvestris), spruce (Picea abies) and birch (Betula pubescens, Betula pendula) trees growing in Southern Finland (SMEAR II station) on varying soil conditions, from upland mineral soils to paludified soil. We compared the CH4 fluxes from trees to forest-floor CH4 exchange, both measured by static chambers, and to CH4 fluxes measured above the forest canopy by a flux gradient technique. We link the CH4 fluxes from trees and forest floor to physiological activity of the trees, such as transpiration, sap-flow, CO2 net ecosystem exchange (NEE), soil properties such as temperature and moisture, and to the presence of CH4 producing methanogens and CH4 oxidizing methanotrophs in trees or soil. The above canopy CH4 flux measurements show that the whole forest ecosystem was a small source of CH4 over extended periods in the spring and summer 2012, 2014 and 2015. Throughout the 2013-2014 measurements, the forest floor was in total a net sink of CH4, with variation

  9. Altitudinal gradients of soil and vegetation carbon and nitrogen in a high altitude nature reserve of Karakoram ranges.

    Science.gov (United States)

    Shedayi, Arshad Ali; Xu, Ming; Naseer, Iqnaa; Khan, Babar

    2016-01-01

    This study aimed to investigate the correlation of carbon and nitrogen in soil and leaves with the altitude, vegetation type, herbaceous biomass (HB), litter mass (LM) and with each other. Soil and leaf samples collected from different forest types along altitudinal gradients in the Karakoram Mountains. Dry and gas law methods were used for the chemical analysis. Regression models used for correlation analysis and T test for comparison. The correlation of soil total carbon (STC) and soil total nitrogen (STN) along altitudinal gradients and correlation between soil organic carbon (SOC) and STN was significantly positive with the values R(2) = 0.1684, p = 0.01, R(2) = 0.1537, p = 0.009 and R(2) = 0.856, p = 7.31E-10 respectively, while it was non-significant between soil inorganic carbon (SIC) and altitude and also between SIC and STN. The concentration of SOC and STN was highest in the broad leaved Betula utilis forest (22.31, 1.6 %) and least in the mixed (Pinus, Juniper, Betula) forest soil (0.85, 0.09 %) respectively. In the tree species leaf total carbon (LTC) and leaf total nitrogen (LTN) were highest in the Pinus wallichiana (PW) (632.54, 19.77), and least in the Populus alba (87.59, 4.06). In the shrub species LTC and LTN nitrogen were highest in the Rosa webiana (235.64, 7.45) and least in the Astragalus gilgitensis (43.45, 1.60) respectively. Total carbon and total nitrogen showed a slightly decreasing and increasing trend with altitude in the leaf and soil samples, respectively. The mean nitrogen and carbon was higher in the leaves of trees (3, 97.95) than in the shrubs (2.725, 74.24) and conifers (2.26, 76.46) than in the leaves of the deciduous (2, 46.36) trees. The correlation between LTC and STN was non-significant. Strong significant (R(2) = 0.608, p = 0.003) and weak non-significant (R(2) = 0.04, p = 0.32) relationships were found in STN and STC with LM and HB respectively. SOC (75.15 %) was found to be the main contributor to

  10. 冀北山地天然次生林土壤有机质空间异质性研究%Spatial Variability of Soil Organic Matte in Natural Secondary Forest

    Institute of Scientific and Technical Information of China (English)

    梁文俊; 魏曦; 朱宝才

    2015-01-01

    【目的】以冀北山地山杨白桦天然次生林为研究对象,探讨该群落土壤垂直方向有机质的分布格局和空间变异特征。【方法】采用大面积野外调查数据,运用统计学、GIS 空间结构分析技术进行分析。结果表明:土壤有机质含量最高的是0~20 cm 层,20~40 cm 有机质含量最小。变异系数随土壤深度的增加逐渐增大,3层都属于中度变异;3层有机质含量的最佳理论模型分别为指数模型、高斯模型和球型模型;各层有机质含量集中区和插值分析分级面积有所不同,但总体变化规律是一致的。0~20 cm 土层土壤有机质含量最大,20~40 cm 层是有机质消耗集中区,有机质含量最小,40~60 cm 层处于中等水平。【结论】研究区是属于次生山杨白桦林,土壤环境受外界破坏较少,土层垂直方向空间变异不显著,母质层有机质的形成和表层土壤有机质的消耗都处在合理的范围内,体现了该区域土壤处于健康、可持续发展的良好状态。%Objective]Populus davidiana + Betula platyphylla natural secondary forest was used as research objective in this study.The aim of this study was to explore the vertical distribu-tion and spatial variation of soil organic matter of the forest.[Method]Field survey data,statis-tics and GIS spatial structure analysis techniques were used in this study.[Results]The content of soil organic matter was the highest in the 0-20 cm layer but the content of 20-40cm was the lowest.The coefficient of variation increased with increasing soil depth and three layers belonged to moderate variation.The best theoretical models of organic matter in three layer were exponen-tial,Gaussian and spherical models.Each layer organic matter content focus area and interpola-tion analysis grade area was different,but the overall change was the same.Soil organic matter of 0 -20 cm layer was the largest.Soil layer of 20-40 cm was

  11. Environmental monitoring program for the Ormen Lange Onshore Processing Plant and the Reserve Power Plant at Nyhamna, Gossa. Monitoring of vegetation and soil: re-analyses and establishment of new monitoring plots in 2010.; Miljoeovervaakingsprogram for Ormen Lange landanlegg og Reservegasskraftverk paa Nyhamna, Gossa. Overvaaking av vegetasjon og jord: gjenanalyser og nyetablering av overvaakingsfelter i 2010

    Energy Technology Data Exchange (ETDEWEB)

    Aarrestad, P.A.; Bakkestuen, V.; Stabbetorp, O.E.; Myklebost, Heidi

    2011-07-01

    conducted for three distinct habitats: wet oligotrophic heathland, and hummocks and lawns on raised bogs. The site in hummocks was established in 2010, whereas the other sites were re-analyzed with the same methods as in 2008. The parameters are monitored within delimited plots. The vegetation is monitored in permanently marked plots (0.5m x 0.5m), ten for each vegetation type at each site, in total 60 plots. In each plot the abundance of vascular plants, bryophytes and lichens are recorded, as well as the cover of the vegetation layers. Plant growth is measured in each site for 20 individuals of Betula nana, Calluna vulgaris, and Sphagnum capillifolium. Five samples of each of Racomitrium lanuginosum, Sphagnum capillifolium and Cladonia arbuscula from each site are collected and analyzed for plant nutrient content and the heavy metals copper (Cu), nickel (Ni), mercury (Hg), lead (Pb), and zinc (Zn). Ten soil samples are collected from each habitat at each site and analyzed for ph, Kjeldahl nitrogen, exchangeable elements, cation exchange capacity, and base saturation, a total of 30 samples from each site. The heavy metals Cu, Ni, Hg, Pb, and Zn are measured in samples of peat mud, 10 samples from each site. Peat water is analyzed for chemical nutrients and heavy metals, 10 samples from each site. The chemical analyses are conducted at the Norwegian Forest and Landscape Institute and NILU. There is still no indication that any pollution has affected the species composition of the vegetation. The vegetation is stable at both sites, both in wet heathland and in lawns on raised bogs. A few species occurring at low frequency in 2008 were not recorded in 2010, and some previously unrecorded species were found. This is normal for re-analyses of vegetation. There were significant differences in plant growth for Betula nana and Calluna vulgaris between the two sites, with highest growth rate at Aukra. This is most likely due to better climatic. (Author)

  12. Community structure and regeneration characteristics of Taxus yunnanensis in northwest Yunnan Province of Southwest China%滇西北云南红豆杉群落结构与更新特征

    Institute of Scientific and Technical Information of China (English)

    刘万德; 李帅锋; 张志钧; 苏建荣

    2012-01-01

    Taking the Taxus yunnanensis communities in northwest Yunnan Province as test ob-jects and based on the field investigation data at three sites ( Lanping, Xianggelila, and Ninglang counties) of northwest Yunnan, this paper analyzed the species composition, species diversity, stem size class, and regeneration features of the T. yunnanensis communities. The dominant spe-cies in the T. yunnanensis communities were Yushania niitakayamensis, Tsuga dumosa, T. yun-nanensis , Betula albo-sinensis, and Fargesia yunnanensis. Xianggelila had the higher species richness of family, genus, and shrubs than the other two counties, but no significant differences were observed in the species richness of trees and lianas and the total species richness among the three counties. Lanping and Xianggelila had the higher species richness and abundance at smal-ler size classes (DBH < 5 cm) , while Ninglang had the highest species richness and abundance at the second diameter class (1 cm≤DBH < 5 cm) and height class (5 cm≤H<10 m). The wild T. yunnanensis population had weak regeneration ability through seedling, but had stronger sprouting ability. The ratio of the stems through sprouting to through seedling was 1. 314. The major sprouting types at all of the three sites were stem basal sprouting and stem epicormic sprou-ting. Ninglang had the highest sprouting stems, but all the three sites had no significant differ-ences in the mean diameter and height of sprouting stems.%以云南西北部云南红豆杉(Taxus yunnanensis)群落为研究对象,利用在兰坪县、香格里拉县和宁蒗县的野外样地调查数据,分析了云南红豆杉群落物种组成、多样性、结构及云南红豆杉更新特征.结果表明:云南红豆杉群落主要物种包括玉山竹(Yushania niitakayamensis)、云南铁杉(Tsuga dumosa)、云南红豆杉、红桦(Betula albo-sinensis)和云南箭竹(Fargesia yunnanensis).香格里拉县具有较高的科、属、灌木物种丰富度,但乔木、

  13. Natural Regeneration Pattern of Urban Forests in Harbin%哈尔滨城市森林自然演替格局研究

    Institute of Scientific and Technical Information of China (English)

    梅琳琳; 冯树丹; 达良俊; 宋坤; 王冰; 关兵兵

    2012-01-01

    In order to strengthen the urban protects of the variety of vegetation biodiversity and reasonable utilization, to perfect the system of ecology theory about the urban vegetation, the author did a lot of research about Haerbin urban forest natural succession pattern. The author decided to adopt the vegetation sociology research combine with every wood investigation research, researching 11 kinds of urban forest natural regeneration pattern in Harbin. The results showed that the difference kinds and quantities of composition about the woody plants under the forest different types of urban forest in maintaining woody plant diversity were quite different. Based on frequency distribution of DBH, population structure of each tree species fell into 3 types: unimodal type, L type and sporadic type. In the case, 4 representative species belonged to unimodal type: Populus berolinensis, Pinus tabulaeformis var. mukdensis, Larix gmelini, Pinus sylvestris var. mongolic; 4 L-types were: Populus davidiana, Phellodendron amurense, Fraxinus mandshurica, and Ulmus pumila; 3 sporadic types were: Juglans mandshurica, Betula platyphylla, and Picea koraiensis. It was suggested that the habitat, the seed resources and the seed dispersal pattern were the key limitation of urban forests.%为了加强城市植被生物多样性的保护与合理利用,完善城市植被生态学研究的理论体系,对哈尔滨城市森林自然演替格局进行研究.采用植被社会学调查与每木调查相结合的方法,对哈尔滨11种城市森林类型进行天然更新格局研究.结果表明,林下木本植物的种类和数量组成有所差异,不同城市森林类型在维持木本植物多样性方面存在较大差异.根据胸径级频率分布的形状,将各树种的种群结构归纳为3种类型:种群结构单峰型的为中东杨(Populus berolinensis)、黑皮油松(Pinus tabulaeformis var.mukdensis)、兴安落叶松(Larix gmelini)、樟子松(Pinus sylvestris var

  14. Comprehensive Evaluation of Forest Community Stability of Different Types of Low-Quality Forest Stands in the Greater Higgnan Mountains%大兴安岭不同类型低质林群落稳定性的综合评价

    Institute of Scientific and Technical Information of China (English)

    宋启亮; 董希斌

    2014-01-01

    The low-quality forest community stability was comprehensively evaluated by calculating subordinate function values of a model which was established based on fuzzy synthetic evaluation by a total of 30 factors of 5 indices of species diversity,soil physical properties,soil chemical properties,litter characteristics and soil carbon flux in 5 typical low-quality forest stands that mixed conifer and broadleaved forest,Populus davidiana forest,Quercus mongolica forest,Betula platyphylla forest and broadleaved mixed forest in the Greater Higgnan Mountains. The results showed that: The indices of species diversity,litter characteristics and soil carbon flux of mixed conifer and broadleaved forest are highest,the index of soil chemical properties of broadleaved mixed forest is highest,the index of soil physical properties of Quercus mongolica forest is highest,forest community stability of 5 types of forest communities in the Great Higgnan Mountains,ranked in the decreasing order of community of mixed conifer and broadleaved forest > broadleaved mixed forest > Quercus mongolica forest>Betula platyphylla forest >Populus davidiana forest. The evaluation results can provide theoretical basis for the ecosystem restoration of low-quality forest stands in the Greater Higgnan Mountains.%以大兴安岭林区分布的针阔混交林、山杨林、蒙古栎林、白桦林和阔叶混交林5种典型低质林森林群落类型为研究对象,选择反映森林群落基本特征的物种多样性、土壤物理性质、土壤化学性质、枯落物特性和土壤碳通量这5项指标,共30个评价因子,运用模糊数学中隶属函数的方法综合评价低质林森林群落稳定性。结果表明:针阔混交林物种多样性、枯落物特性、土壤碳通量指标最高,阔叶混交林土壤化学性质指标最高,蒙古栎林土壤物理性质指标最高,大兴安岭5种森林群落稳定性表现为针阔混交林>阔叶混交林>蒙古栎林>白

  15. Stomatal regulation, structural acclimation and metabolic shift towards defensive compounds reduce O3 load in birch under chronic O3 stress

    Science.gov (United States)

    Oksanen, E.; Riikonen, J.; Kontunen-Soppela, S.; Maenpaa, M.; Rousi, M.

    2009-12-01

    Northern forests are encountering new threats due to continuously increasing load of oxidative stress, e.g. due to rising tropospheric O3 levels, and simultaneous climate warming, which is more intense in northern latitudes as compared to global means. The proportion of silver birch (Betula pendula) in Finnish forests is expected to increase with climate warming. Unfortunately, we have growing evidence that the vitality and the carbon sink strength of birch trees are weakened under chronic O3 stress. In this study we investigated the effects of slightly elevated O3 concentration (1.3 x the ambient), temperature (T) and their combination on the antioxidant defense, gas exchange and leaf growth of Betula pendula saplings (clone 12) growing in open-field conditions over two growing seasons. The plants were measured for SLA (specific leaf area), total leaf area, net photosynthesis (Pn), stomatal conductance (gs), maximum rate of carboxylation (Vc,max), maximum rate of electron transport (Jmax), relative stomatal limitation to photosynthesis (ls), dark respiration (Rd), apoplastic concentrations of AA (ascorbic acid), DHA (dehydroascobate) and total ascorbate, the redox state of apoplastic ascorbate, and total antioxidant capacity. Elevated O3 enhanced the total antioxidant capacity in the apoplast in the first year of the experiment at the ambient T. However, during the second year of the experiment, the saplings responded to elevated O3 level by closing the stomata and by developing leaves with a lower leaf area per mass, rather than by accumulating ascorbate in the apoplast. O3 did not affect the total leaf area, whereas Pn was slightly and gs significantly reduced in the second year. Elevated T enhanced the total leaf area, Pn and Vc,max, redox state of ascorbate and total antioxidant capacity in the apoplast. The effects of T and O3 on total leaf area and net photosynthesis were counteractive. We were not able to detect significant differences in Rd between the

  16. Environmental monitoring program for the Ormen Lange Onshore Processing Plant and the Reserve Power Plant at Nyhamna, Gossa. Monitoring of vegetation and soil: re-analyses and establishment of new monitoring plots in 2010

    International Nuclear Information System (INIS)

    conducted for three distinct habitats: wet oligotrophic heathland, and hummocks and lawns on raised bogs. The site in hummocks was established in 2010, whereas the other sites were re-analyzed with the same methods as in 2008. The parameters are monitored within delimited plots. The vegetation is monitored in permanently marked plots (0.5m x 0.5m), ten for each vegetation type at each site, in total 60 plots. In each plot the abundance of vascular plants, bryophytes and lichens are recorded, as well as the cover of the vegetation layers. Plant growth is measured in each site for 20 individuals of Betula nana, Calluna vulgaris, and Sphagnum capillifolium. Five samples of each of Racomitrium lanuginosum, Sphagnum capillifolium and Cladonia arbuscula from each site are collected and analyzed for plant nutrient content and the heavy metals copper (Cu), nickel (Ni), mercury (Hg), lead (Pb), and zinc (Zn). Ten soil samples are collected from each habitat at each site and analyzed for ph, Kjeldahl nitrogen, exchangeable elements, cation exchange capacity, and base saturation, a total of 30 samples from each site. The heavy metals Cu, Ni, Hg, Pb, and Zn are measured in samples of peat mud, 10 samples from each site. Peat water is analyzed for chemical nutrients and heavy metals, 10 samples from each site. The chemical analyses are conducted at the Norwegian Forest and Landscape Institute and NILU. There is still no indication that any pollution has affected the species composition of the vegetation. The vegetation is stable at both sites, both in wet heathland and in lawns on raised bogs. A few species occurring at low frequency in 2008 were not recorded in 2010, and some previously unrecorded species were found. This is normal for re-analyses of vegetation. There were significant differences in plant growth for Betula nana and Calluna vulgaris between the two sites, with highest growth rate at Aukra. This is most likely due to better climatic. (Author)

  17. Holocene local forest history at two sites in Småland, southern Sweden - insights from quantitative reconstructions using the Landscape Reconstruction Algorithm

    Science.gov (United States)

    Cui, Qiaoyu; Gaillard, Marie-José; Lemdahl, Geoffrey; Olsson, Fredrik; Sugita, Shinya

    2010-05-01

    et al.; Trondman et al., CL 1.22; Mazier et al. CL 1.21) we used 3 sets of pollen taxa (20, 22, 31) and 3 sets of pollen productivity estimates (PPEs) (1. southern Sweden; 2. southern Sweden except for cereals, Calluna, Plantago and Rumex, Denmark; 3. the mean of all PPEs available in NW Europe). The Spearman rank correlation test shows that there are no significant differences between the 9 runs. LOVE was applied on the pollen records from the two small bogs following the same strategy. We also compared the LOVE estimates (20 taxa, PPEs dataset 2) with the records of plant macro-remains and coleoptera species that are indicators of the local occurrence of conifers (Pinus and Picea), Betula, and deciduous trees. The results show large discrepancies between the LOVE estimates and pollen percentages. The LOVE estimates are higher than pollen percentages for Cyperaceae, Gramineae and Filipendula, and the broaded-leaved trees Corylus, Fraxinus, and Tilia. In contrast, the LOVE estimates for Pinus and Betula are generally much lower than their pollen percentages. LOVE estimates and pollen percentages are relatively similar for Alnus, Quercus, and Calluna. The LOVE reconstruction confirms the assumed difference between the sites in terms of the abundance of birch and pine, which was not clearly demonstrated by the pollen percentages and accumulation rates. The Pinus LOVE estimates are significantly higher at one of the sites, which explains the differences in fire history between the sites. The comparison of the LOVE estimates with plant macro-remains and coleoptera species shows a good correspondence. References: Greisman, A. and Gaillard, MJ, 2009. Journal of Quaternary Science, 24(6):593-611. Olsson, F. et al. 2009. Palaeogeography, Palaeoclimatology, Palaeoecology, 10.1016/j.palaeo.2009.07.013 Sugita, S., 1993. Quaternary Research, 39:239-244. Sugita, S., 2007a. The Holocene, 17(2):229-241. Sugita, S., 2007b. The Holocene, 17(2):243-257.

  18. Usability of multiangular imaging spectroscopy data for analysis of vegetation canopy shadow fraction in boreal forest

    Science.gov (United States)

    Markiet, Vincent; Perheentupa, Viljami; Mõttus, Matti; Hernández-Clemente, Rocío

    2016-04-01

    Imaging spectroscopy is a remote sensing technology which records continuous spectral data at a very high (better than 10 nm) resolution. Such spectral images can be used to monitor, for example, the photosynthetic activity of vegetation. Photosynthetic activity is dependent on varying light conditions and varies within the canopy. To measure this variation we need very high spatial resolution data with resolution better than the dominating canopy element size (e.g., tree crown in a forest canopy). This is useful, e.g., for detecting photosynthetic downregulation and thus plant stress. Canopy illumination conditions are often quantified using the shadow fraction: the fraction of visible foliage which is not sunlit. Shadow fraction is known to depend on view angle (e.g., hot spot images have very low shadow fraction). Hence, multiple observation angles potentially increase the range of shadow fraction in the imagery in high spatial resolution imaging spectroscopy data. To investigate the potential of multi-angle imaging spectroscopy in investigating canopy processes which vary with shadow fraction, we obtained a unique multiangular airborne imaging spectroscopy data for the Hyytiälä forest research station located in Finland (61° 50'N, 24° 17'E) in July 2015. The main tree species are Norway spruce (Picea abies L. karst), Scots pine (Pinus sylvestris L.) and birch (Betula pubescens Ehrh., Betula pendula Roth). We used an airborne hyperspectral sensor AISA Eagle II (Specim - Spectral Imaging Ltd., Finland) mounted on a tilting platform. The tilting platform allowed us to measure at nadir and approximately 35 degrees off-nadir. The hyperspectral sensor has a 37.5 degrees field of view (FOV), 0.6m pixel size, 128 spectral bands with an average spectral bandwidth of 4.6nm and is sensitive in the 400-1000 nm spectral region. The airborne data was radiometrically, atmospherically and geometrically processed using the Parge and Atcor software (Re Se applications Schl

  19. Radioactive caesium in Boreal forest landscapes - Dynamics and transport in food webs. Summary of research 1986-1996

    International Nuclear Information System (INIS)

    The need for - but also the paucity of - radioecological knowledge concerning the boreal forest became particularly apparent after the nuclear power plant accident in Chernobyl in April 1986. As a consequence several new projects were initiated in the Nordic countries with particular focus on the behaviour of radioactive caesium in terrestrial and aquatic systems characteristic for the Fenno-Scandinavian landscapes. Among these new projects a multi-disciplinary co-operation in Umeaa between scientists at the Swedish University of Agricultural Sciences, and the Defence Research Establishment emerged. Initially this joint work focused mainly on descriptions of the dynamic changes of the content of radioactive caesium in soil-plant and animal communities in the county of Vaesterbotten. Most of the studies have been performed at the Vindeln experimental forest, 60 km NW of Umeaa. Plants of key interest were: bilberry (Vaccinium myrtillus), birch (Betula spp.), and pine (Pinus sylvestris), and among the animals: the moose (Alces alces) and a small rodent, the forest vole (Clethrionomus glareolus). Gradually over the past ten years the research has entered the stage where the specific causes of the caesium behaviour have been addressed - partly by the help of models developed for simulating forest ecosystems, partly by complementary field experiments. This paper reviews our main findings on this theme concerning the behaviour of radioactive caesium in boreal landscapes and significant pathways to man, as has become apparent from the radioecological co-operation dating from about ten years back. A list of the publications arising from these studies since 1986 is also presented in this report

  20. Bud flush phenology and nursery carryover effect of paper birch provenances

    Directory of Open Access Journals (Sweden)

    Dhar A

    2015-12-01

    Full Text Available Paper birch (Betula papyrifera Marsh is an ecologically valuable species with a broad geographic distribution across the North America. Its diversity, versatility and enduring nature make it an ideal candidate for a selective breeding program in this region. However, an understanding of the genecology of this species is fundamental to deploy it successfully. Ten paper birch provenances were collected from British Columbia (BC, Canada and northern Idaho (USA along elevational transects to determine whether observed bud flush phenology was due to genetics and /or environmental variation or their interaction. Seedlings were grown at three different nurseries: University of Idaho (46°44’N, Landing (50°17’N and Little Forestry (54°00’N and planted in a randomized single tree interlocking block design in three common gardens at Sandpoint, ID (48°13’N, Skimikin, BC (50°45’N and Red Rock, BC (53°45’N. Results indicate that variation in the timing of bud flush is a complex interaction among local genetic characteristics and environmental conditions of the growing site. Birch bud flush followed a general geographic trend where provenances at the southern common garden (Sandpoint required less time (Day of Year, DoY and fewer growing degree days (GDD compared to central (Skimikin and northern (Red Rock common gardens. Although there were significant differences in the timing of bud flush among provenances along an elevational gradient, none of the regions showed the expected linear elevational cline, trends were inconsistent. Further, birch bud flush was significantly influenced by nursery displacement effects in the initial year of establishment but disappeared within three years. These results provide an opportunity to characterize bud flush phenology of paper birch and would be useful for improving operational paper birch seed transfer programs in BC.

  1. Plant Pb Contents in Elevation Zones of the Changbai Mountain National Nature Reserve, China

    Institute of Scientific and Technical Information of China (English)

    BAI Jun-Hong; CUI Bao-Shan; DENG Wei; WANG Qing-Gai; DING Qiu-Yi

    2007-01-01

    Typical plants and soils of four elevation zones,mountain tundra(Zone A),Betula ermanii forest(Zone B),mountain dark coniferous forest(Zone C),and mountain coniferous and broad-leaf forest(Zone D),along the vertical gradient of the northern mountain slope of the Changbai Mountain National Nature Reserve,Jilin Province,China,were sampled to study the relationship between plant and soil Pb,and to compare the Pb levels in typical plant types within the same elevation zone.The Pb contents in the soil and plant samples were measured by using a flame atomic absorption spectrophotometer.The results showed that the average plant Pb contents of the four plant elevation zones were lower than the average worldwide level.except for Zone B,Compared with the average level in China or the average worldwide level,the soil Pb levels of the four plant zones were higher,with Zones D and B having the lowest and highest averages,respectively.Plant Pb levels fluctuated from the upper to the lower zones,in a pattern of low-high-low-high,which was the same as that of the soils in the four zones.Furthermore.plant Pb was closely related to soll Pb.Depending on the plant species and plant parts,large differences were found in the Pb levels of typical plants within each zone.In Zone A,Vaccinium uliginosum and Rhododendron redowskianum had higher Pb levels than the other plants.In Zone C,the Pb levels in the branches of both plant species were higher than those in the leaves,which was contrary to Zone D.In Zone B,the Pb levels in the plant parts varied greatly with plant species.

  2. Thermal analysis of wood of the main tree species of Central Siberia

    Directory of Open Access Journals (Sweden)

    S. R. Loskutov

    2015-12-01

    Full Text Available Thermal decomposition of wood from coniferous and deciduous species of Siberia has been studied using thermogravimetry (TG and differential scanning calorimetry (DSC. The tree species were larch Larix sibirica Ledeb., Scots pine Pinus sylvestris L., spruce Picea obovata Ledeb., fir Abies sibirica Ledeb., Siberian pine Pinus sibirica Du Tour., birch Betula pendula Roth., and aspen Populus tremula L. Thermal analysis of wood samples was carried out under oxidative (air and inert (argon atmospheres from 25 to 700 °С at heating rates 10, 20, 40 °С • min–1 (TG/DTG and from 25 to 590 °С at heating rates 10, 40 °С • min–1 (DSC. The stages of thermal decomposition, the temperature intervals, the mass loss, the mass loss rate, the temperature of DTG/DSC peaks, and heating effects were determined for each tree species. The kinetic thermal degradation parameters of wood were obtained by the Broido and Ozawa–Flynn–Wall models. The wood of coniferous and deciduous species of Siberia was characterized on the base of analysis of activation energy values at various stages of thermal decomposition and the relations of activation energy on conversion level of wood substance of different tree species, and also the comparison of mass loss at the same stages of thermal destruction, heating effects, residual mass and other parameters of TG/DTG, DSC. In our opinion, the results of this work present interest for researchers and specialists in the field of forest pyrology, wood science, dendrochemistry.

  3. Environmental and Physiological Controls on Plant Leaf Wax δD from Western Greenland

    Science.gov (United States)

    Berke, M. A.; Bush, R. T.; Cartagena Sierra, A.; Cheah, D.; Costello, C.; Muldoon, T.; Tillema, M.

    2015-12-01

    Hydrogen isotope ratios of leaf waxes are increasingly used to reconstruct past hydroclimate, but the interpretation of these signatures from ancient sedimentary archives relies on a thorough understanding of the drivers of isotope variability in modern environments. These studies are particularly valuable in the arctic and subarctic, regions particularly vulnerable to rapid climate change, but where modern vegetation is understudied compared to proxy applications reliant on vegetation. Here we present δD values from leaf wax compounds of tundra vegetation in the Kangerlussuaq area of western Greenland. We collected samples along a transect that follows 12 sites from the base of the Greenland Ice Sheet, around a small lake ('Bird Lake') and to the town of Kangerlussuaq, along the Sandflugtdalen ('Flying Sand Valley'). We collected a variety of common tundra species in these locations including dwarf shrubs (e.g. Betula nana, Rhododendron lapponica, and Salix glauca), forbs and graminoids (e.g. Calamagrostis lapponica and Eriophorum angustifolium), and horsetails (Equisetum arvense) to study possible interspecies isotopic variability. We measured leaf and stem waters of these plants to help constrain potential drivers of leaf wax n-alkane δD values across this transect. Results are discussed relative to local climate parameters and modelled precipitation values to elucidate source water contributions modified by evaporation and transpiration. This survey of δD values from leaf wax compounds and plant waters in western Greenland will extend stable isotope calibrations to tundra vegetation and provide insights into the use of sedimentary leaf wax compounds for reconstruction of paleohydroclimate.

  4. Methods and applications to control the uptake rate of carbon

    Energy Technology Data Exchange (ETDEWEB)

    Ingestad, T.; Hellgren, O.; Hesseldahl, H.; Lund Ingestad, A.B.

    1996-12-01

    Methods to control carbon and nutrient uptake at different availability of carbon were tested on plants of birch (Betula pendula Roth.) and tomato (Lycopersicon esculentum Mill. cv. Solentos). The present paper accounts for the methods and the possibility to maintain steady-state, i.e., a long-term and stable physiological state of acclimated plants. Steady-state comprises, by definition, equality between constant relative growth rates, and relative uptake rates of carbon and nutrients. Two methods were tested. The first, not previously applied, method (a), was based on a constant relative addition rate of carbon, R{sub AC}. In the second method (b), a constant concentration of CO{sub 2} in the air, C{sub a}, was used to attain non-limiting conditions. The methods are analogous to those used by us to control plant nutrition, and the generality of fluxes to quantify supply as well as uptake and growth was verified. Thus, different R{sub AC} resulted in clear-cut responses, from strong reduction to non-limitation of uptake and growth, whereas different c{sub a} levels in the range 100 to 700 ppm had comparatively small effects, with an unclear causality. Non-limiting conditions were achieved at c{sub a} {>=} 200 ppm. Transpiration rate increased rapidly at c{sub a} < 200 ppm CO{sub 2}, and at low R{sub AC} levels < o.1 day{sup -1}, wilting tendencies were observed. Elevated c{sub a}, 500 or 700 ppm, did not increase the relative growth rate (G{sub G}) but reduced transpiration and increased both nitrogen productivity (growth rate per unit of nitrogen in the plant) and transpiration productivity (growth rate per unit of water transpired by the plant). (EG)

  5. Air quality in the mountain climate-balneological resort Kislovodsk

    Science.gov (United States)

    Chalaya, Elena; Efimenko, Natalia; Povolotckaia, Nina; Senik, Irina; Slepykh, Victor

    2016-04-01

    There has been studied the quality of the surface atmosphere in the mountain climate-balneological resort Kislovodsk (MCBRK) to treat by means of climate and landscape (TCL) of the patients suffering from bronchial asthma (PBA) [1]. 60 children (31 boys and 29 girls at the age of 9-11 years) were examined in the course of 34 days of the resort treatment in MCBRK, PBA (ICD-10 G45,0) in a remission stage. There have been used the data of the long-term bioclimatic monitoring (BCM) that is carried out by PRIC FMBA, aerosol monitoring of IFA RAS, landscape monitoring of SNP in Kislovodsk Resort Park (KRP) as well as the data of medical monitoring, daily testing of meteopathic reactions (MPR), indicators dynamics of bronchial patency, cardiac rhythm, neurovascular reactivity, psychoemotional status of patients. TCL was carried out in the form of walks under the canopy of Betula pendula Roth., Salix f. pendula, acer platanoides globosum, Aesculus hippocastanum L., Phellodendron amurense, Tilia caucasica in KRP daily lasting from 1 till 2 hours. The results of a complex research showed that at TCL in KRP the favourable heat balance had 92% warm relations (TB300C), aerosol growth till 6-12 particles/cm3 in the blocking anti-cyclone. Conclusion: the surface atmosphere in KRP is mainly at the level of background rural territories, it is perspective for usage in the medical and improving purposes. Episodes of slightly polluted surface atmosphere are connected with forest fires, autopollution during the periods of the blocking anti-cyclones. References 1. Resort study of Caucasian Mineral Vody region/Under the general edition of MD, prof. V.V. Uyba. Scientific publication. - Pyatigorsk: PRIC FMBA. Volume 1. - 2009. - 335p; Volume 2. - 2011. - 368p.

  6. Vegetation biomass and habitat selection by a newly introduced population of muskoxen in northern Quebec

    Directory of Open Access Journals (Sweden)

    René Nault

    1993-12-01

    Full Text Available Ground coverage by woody and herbaceous plant species and standing biomass of vegetation susceptible to being grazed upon were estimated in a 156 km2 area where 190 muskoxen were censused during the preceding autumn. Habitat use was estimated with droppings census. Six terrestrial habitat types were delineated on 1:32 000 aerial photographs and randomly sampled: low shrub on xeric sites (LSX; 64 km2, low shrub on mesic sites (LSM; 45 km2, bare ground (BG; 27 km2, forest-tundra (FT; 12 km2, wet meadow (WM; 2 km2 and riparian willows (RW; 1 km2. Dominant plant species varied greatly between habitat types, and only a few such as Betula glandulosa, Salix arctophila, and Polygonum viviparum were common. Tall shrubs were present only in RW where they covered most of the ground, and in FT. Low shrubs were uniformly distributed and covered 18-32% of the ground, with the exception of RW (5%. Ground cover by herbs had a similar range (i.e. 20-37%, except in RW where the mean exceeded 50%. Mosses and lichens occupied about half of the ground everywhere. Phytomass exhibited great variation within and between habitat types; extreme values averaged 892 kg*ha-1 in LSX, and 1965 kg*ha-1 in LSM. However the difference was not significant due to limited sample size and within habitat variance. Nevertheless the mass of herbaceous dicots was greater in RW than in any other habitat type. Total phytomass was 2-20 times greater in northern Québec than in Greenland. Based on droppings density, muskoxen preferred RW over BG and FT, and LSX over BG. Although the density of muskoxen in the study area was high relative to other muskox ranges, habitat quality and quantity should allow continued population growth.

  7. The sensitivity of stand-scale photosynthesis and transpiration to changes in atmospheric CO2 concentration and climate

    Directory of Open Access Journals (Sweden)

    B. Kruijt

    1999-01-01

    Full Text Available The 3-dimensional forest model MAESTRO was used to simulate daily and annual photosynthesis and transpiration fluxes of forest stands and the sensitivity of these fluxes to potential changes in atmospheric CO2 concentration ([CO2], temperature, water stress and phenology. The effects of possible feed-backs from increased leaf area and limitations to leaf nutrition were simulated by imposing changes in leaf area and nitrogen content. Two different tree species were considered: Picea sitchensis (Bong. Carr., a conifer with long needle longevity and large leaf area, and Betula pendula Roth., a broad-leaved deciduous species with an open canopy and small leaf area. Canopy photosynthetic production in trees was predicted to increase with atmospheric [CO2] and length of the growing season and to decrease with increased water stress. Associated increases in leaf area increased production further only in the B. pendula canopy, where the original leaf area was relatively small. Assumed limitations in N uptake affected B. pendula more than P. sitchensis. The effect of increased temperature was shown to depend on leaf area and nitrogen content. The different sensitivities of the two species were related to their very different canopy structure. Increased [CO2] reduced transpiration, but larger leaf area, early leaf growth, and higher temperature all led to increased water use. These effects were limited by feedbacks from soil water stress. The simulations suggest that, with the projected climate change, there is some increase in stand annual `water use efficiency', but the actual water losses to the atmosphere may not always decrease.

  8. Variación de la vegetación holocena (4300-280 B.P. de Cantabria a traves del análisis polínico de la turbera del Alsa

    Directory of Open Access Journals (Sweden)

    Mariscal, B.

    1993-04-01

    Full Text Available This paper describes the palinological study carried out in a peat deposit in Bárcena Pie de Concha (Cantabria, Spain. A 2,6 m. profile was obtained and 24 samples were studied. Three samples were also dated by 14C. and the ages were also determined (4310 to 280 years B.P.. The data obtained shows that the peat was formed between the Atlantic and the Subboreal, the Subatlantique periods appear well defined in the diagrams. Three phases have been distinguished in the microflora. A inferior section of the profile, characterized by the predominance of Pinus sp. pollen; a second or middle section in which pollen belonging to caducifolium trees, Betula sp. and Corylus avellana, and third or superior section which in characterized by an increase of herbaceous plants, like Ericaceae.Se incluyen los diagramas polínicos con las especies arbóreas y no arbóreas correspondiente a los 2,6 m. de perfil de la turbera, lo que supone el análisis polínico de 24 muestras de turba. Las dataciones absolutas (C-14, obtenidas, muestran que la turbera se formó entre los 4310 y los 280 años B.P. El inicio de la turbera se produce durante la transición entre el período climático Atlántico y el Subboreal, y tanto estos dos períodos como el Subatlántico aparecen bien definidos en el Palinograma. Se han podido diferenciar tres fases en la microflora. Una parte inferior, que se caracteriza por el predominio del polen de Pinus sp.; una parte media en la que abundan los pólenes de árboles caducifolios fundamentalmente Betuna, sp. y Corylus avellana y una parte superior que se caracteriza por un aumento de las plantas herbáceas como Ericaceae.

  9. Tree Species Linked to Large Differences in Ecosystem Carbon Distribution in the Boreal Forest of Alaska

    Science.gov (United States)

    Melvin, A. M.; Mack, M. C.; Johnstone, J. F.; Schuur, E. A. G.; Genet, H.; McGuire, A. D.

    2014-12-01

    In the boreal forest of Alaska, increased fire severity associated with climate change is altering plant-soil-microbial feedbacks and ecosystem carbon (C) dynamics. The boreal landscape has historically been dominated by black spruce (Picea mariana), a tree species associated with slow C turnover and large soil organic matter (SOM) accumulation. Historically, low severity fires have led to black spruce regeneration post-fire, thereby maintaining slow C cycling rates and large SOM pools. In recent decades however, an increase in high severity fires has led to greater consumption of the soil organic layer (SOL) during fire and subsequent establishment of deciduous tree species in areas previously dominated by black spruce. This shift to a more deciduous dominated landscape has many implications for ecosystem structure and function, as well as feedbacks to global C cycling. To improve our understanding of how boreal tree species affect C cycling, we quantified above- and belowground C stocks and fluxes in adjacent, mid-successional stands of black spruce and Alaska paper birch (Betula neoalaskana) that established following a 1958 fire near Fairbanks, Alaska. Although total ecosystem C pools (aboveground live tree biomass + dead wood + SOL + top 10 cm of mineral soil) were similar for the two stand types, the distribution of C among pools was markedly different. In black spruce, 78% of measured C was found in soil pools, primarily in the SOL, where spruce contained twice the C stored in paper birch (4.8 ± 0.3 vs. 2.4 ± 0.1 kg C m-2). In contrast, aboveground biomass dominated ecosystem C pools in birch forest (6.0 ± 0.3 vs. 2.5 ± 0.2 kg C m-2 in birch and spruce, respectively). Our findings suggest that tree species exert a strong influence over plant-soil-microbial feedbacks and may have long-term effects on ecosystem C sequestration and storage that feedback to the climate system.

  10. 拉萨-林芝植被样带不同群落类型的细根生物量%Biomass of Fine Root in Different Community Type on the Tibetan Vegetation Transect

    Institute of Scientific and Technical Information of China (English)

    何永涛; 石培礼; 徐玲玲

    2009-01-01

    Fine root biomass was measured by soil core sampler in four community type on Tibetan Plateau, of which include two coppice of Betida platyphylla and Quercus aquifolioides , one shrub of Salix oritrepha, and one coniferous woodland of Pinus densata. The fine root density were Betida platyphylla of (785.9±290.4) g·m~(-2), Quercus aquifolioides of (801.0±279.5) g·m~(-2) , Salix oritrepha of (376.0±146.0) g·m~(-2) and Pinus densata of (431.2 ±171.1) g·m~(-2) . Result showed that the fine root density of two coppices was significantly higher than that of shrub and coniferous woodland. Dead fine root was 16.2% of the total fine root in Betula platyphylla, and the percentage were about 25% in other three type of forest. Distribution of fine root had the same pattern that high density of fine root appeared at 0~10 cm soil depth.%@@ 细根通常是指植被地下根系中直径小于2 nun的根,其生产和周转直接影响着整个生态系统的碳平衡和养分循环.在森林生态系统中约3%~84%(大部分为10%-60%)的净初级生产力被用于细根的生产(张小全等,2001);而细根的周转则是森林土壤C累积的最大输入量,如果忽略细根的生产、死亡和分解,土壤有机物质和养分元素的周转将被低估20%-80%(Vogt et al.,1986;1996).

  11. 铁杉球蚜的生物学及空间分布%Biology of the hemlock woolly adelgid, Adelges tsugae, and its spatial distribution

    Institute of Scientific and Technical Information of China (English)

    周建华; 肖银波; 肖育贵; 卢文华

    2007-01-01

    通过对铁杉(Tusga chinensis Pritz)-云杉(Picea retroflexac Mast)、铁杉-华山松(Pinus armardi Franch)、云南铁杉(Tusga domosa Eichler)-槭树(Acer mono Maxim)-桦木(Betula platyphylla Suk)四川主要铁杉林类型中铁杉球蚜Adelges tsugae Annand林间定株、种群随机抽样、室内饲养研究表明,铁杉球蚜在四川1年发生2代(越冬代和第1代),世代重叠,成虫营孤雌生殖.越冬代从4月上旬至第2年的4月下旬,产卵盛期在5月下旬,平均产卵量为15.58粒,1龄若虫具有滞育越夏习性;第1代从12月下旬至8月中旬,产卵盛期在3月下旬,平均产卵量为67.37粒,并可产生有翅成虫,但无转主危害现象.种群的发育与温度有相关性,温度高林分种群发育进度快于温度低林分.该虫的危害与生境有一定相关性,铁杉针阔混交林危害重于铁杉针叶林;同一树冠不同层次之间、不同方位之间危害程度差异不显著;当年受害严重的树株第2年受害不严重.

  12. Toward an improved model of maple sap exudation: the location and role of osmotic barriers in sugar maple, butternut and white birch.

    Science.gov (United States)

    Cirelli, Damián; Jagels, Richard; Tyree, Melvin T

    2008-08-01

    Two theories have been proposed to explain how high positive pressures are developed in sugar maple stems when temperatures fluctuate around freezing. The Milburn-O'Malley theory proposes that pressure development is purely physical and does not require living cells or sucrose. The osmotic theory invokes the involvement of living cells and sucrose to generate an osmotic pressure difference between fibers and vessels, which are assumed to be separated by an osmotic barrier. We analyzed wood of Acer saccharum Marsh., Juglans cinerea L. and Betula papyrifera Marsh. (all generate positive pressures) examining three critical components of the osmotic model: pits in cell walls, selectivity of the osmotic barrier and stability of air bubbles under positive xylem pressure. We examined the distribution and type of pits directly by light and scanning electron microscopy (SEM), and indirectly by perfusion of branch segments with fluorescent dyes with molecular masses similar to sucrose. The latter approach allowed us to use osmotic surrogates for sucrose that could be tracked by epifluorescence. Infusion experiments were used to assess the compartmentalization of sucrose and to determine the behavior of gas bubbles as predicted by Fick's and Henry's laws. The SEM images of sugar maple revealed a lack of pitting between fibers and vessels but connections between fiber-tracheids and vessels were present. Fluorescein-perfusion experiments demonstrated that large molecules do not diffuse into libriform fibers but are confined within the domain of vessels, parenchyma and fiber-tracheids. Results of the infusion experiments were in agreement with those of the fluorescein perfusions and further indicated the necessity of a compartmentalized osmolyte to drive stem pressure, as well as the inability of air bubbles to maintain such pressure because of instability. These results support the osmotic model and demonstrate that the secondary cell wall is an effective osmotic barrier for

  13. Ecological and phytopathological status of birch stands on the territory of Krasnoyarsk group of districts

    Directory of Open Access Journals (Sweden)

    A. I. Tatarintsev

    2015-04-01

    Full Text Available According to inspection data, the health and vital status of birch (Betula pendula Roth. stands in Krasnoyarsk group of lands (southern part of Central Siberia were estimated (established as satisfactory in general; about half of birch stands near urbanized areas were weakened. The condition of stands decreased significantly with increased recreation use, the effect of technogenic pollution was negligible. The most valuable (important representatives of pathogenic biota identified on birch trees were infestations of necrotic cancer and rot diseases. In birch stands the bacterial dropsy was found to be widespread (agent of infection – Erwinia multivora Scz.-Parf, occurrence of the disease ranged from a single ill tree up to 10–38 % of the stands. The birch stands in taiga areas were affected to a greater extent than in forest-steppe; there were high yield class stands on moist soils. Prevalence of bacteriosis rose with increasing stand age and density and not dependent on recreation use level. Trees with dropsy are dead in fact or potentially. In taiga birch forests the infection and rot of roots was caused by honey agaric (Armillaria mellea sensu lato, that lead to single or, rarely, group tree drying and the fungus usually eliminated already weakened trees. Wood biomass was destroyed by complex of aphyllophorous Hymenomycetes, their hemiparasitic species caused stem rots that decreased stand marketability and also resulted in rot-realated wind-break accumulation. Occurrence of rot was significantly higher in second growth birch stands, possibly above 20 %; the relationship between rot prevalence and forest assessment was not revealed.

  14. Photosynthetic downregulation in leaves of the Japanese white birch grown under elevated CO{sub 2} concentration does not change their temperature-dependent susceptibility to photoinhibition

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, M.; Tobita, H.; Yazaki, K.; Kitao, M. [Forestry and Forest Products Research Institute. Dept. of Plant Ecology, Tsukuba (Japan); Watanabe, M.; Koike, T. [Hokkaido Univ.. Dept. of Forest Science, Sapporo (Japan)

    2013-02-15

    To determine the effects of elevated CO{sub 2} concentration ([CO{sub 2}]) on the temperature-dependent photosynthetic properties, we measured gas exchange and chlorophyll fluorescence at various leaf temperatures (15, 20, 25, 30, 35 and 40 deg. C) in 1-year-old seedlings of the Japanese white birch (Betula platyphylla var. japonica), grown in a phytotron under natural daylight at two [CO{sub 2}] levels (ambient: 400 {mu}mol mol{sup -1} and elevated: 800 {mu}mol mol{sup -1}) and limited N availability (90 mg N plant{sup -1}). Plants grown under elevated [CO{sub 2}] exhibited photosynthetic downregulation, indicated by a decrease in the carboxylation capacity of Rubisco. At temperatures above 30 deg. C, the net photosynthetic rates of elevated-CO{sub 2}-grown plants exceeded those grown under ambient [CO{sub 2}] when compared at their growth [CO{sub 2}]. Electron transport rates were significantly lower in elevated-CO{sub 2}-grown plants than ambient-CO{sub 2}-grown ones at temperatures below 25 deg. C. However, no significant difference was observed in the fraction of excess light energy [(1 - q{sub P})x F{sub v}'/F{sub m}'] between CO{sub 2} treatments across the temperature range. The quantum yield of regulated non-photochemical energy loss was significantly higher in elevated-CO{sub 2}-grown plants than ambient, when compared at their respective growth [CO{sub 2}] below 25 deg. C. These results suggest that elevated-CO{sub 2}-induced downregulation might not exacerbate the temperature-dependent susceptibility to photoinhibition, because reduced energy consumption by electron transport was compensated for by increased thermal energy dissipation at low temperatures. (Author)

  15. Suitability of thermoluminescence, chemiluminescence, ESR and viscosity measurements as detection method for the irradiation of medicinal herbs; Eignung von Thermolumineszenz-, Chemilumineszenz-, ESR- und Viskositaetsmessungen zur Identifizierung strahlenbehandelter Arzneidrogen

    Energy Technology Data Exchange (ETDEWEB)

    Schuettler, C.; Gebhardt, G.; Stock, A.; Helle, N.; Boegl, K.W.

    1993-12-31

    Chemiluminescence, electron spin resonance, thermoluminescence and viscosity measurements have been investigated for their suitability as detection method for the irradiation of the medicinal herbs anise seeds (anisi fructus), valerian roots (valerianae radix), redberry leaves (uvae ursi folium), birch leaves (betulae folium), greek hay seeds (foenugraeci semen), cayenne pepper (capsici fructus acer), black-aldertee bark (frangulae cortex), fennel fruits (feoniculi fructus), rose hip shells (cynosbati fructus), coltsfoot (farfarae folium), acorus roots (calami rhizoma), chamomile flowers (matricariae flos), caraway (carvi fructus), lavender flowers (lavandulae flos), linseed (lini semen), lime tree flowers (tiliae flos), St. Mary`s thistle fruit (cardui mariae herba), lemon balm (melissae folium), java tea (orthosiphonis folium), peppermint (menthae piperitae folium), sage leaves (salviae folium), scouring rush (equiseti herba), senna leaves (sennae folium), plantain herbs (plantaginis lanceolata herba), thyme herbs (thymi herba), juniper berries (juniperi fructus), hawthorne herbs (crataegi folium), wheat starch (amylum tritici) and wormwood (absinthii herba). Depending on the herbs, the methods used were more or less suitable. Chemiluminescence measurements showed the smallest differences between untreated and irradiated samples whereas thermoluminescence measurements on isolated minerals from the vegetable drugs gave better results. In some herbs radiation-specific radicals could be identified by ESR spectroscopy. Viscosity measurement is suitable for some herbs as fast and inexpensive method for screening. (orig.) [Deutsch] Die Eignung von Chemilumineszenz-, ESR-, Thermolumineszenz- und Viskositaetsmessungen als Nachweismethode fuer die Behandlung von Arzneidrogen mit ionisierenden Strahlen wurde an Anis, Baldrianwurzel, Baerentraubenblaettern, Birkenblaettern, Bockshornsamen, Cayennepfeffer, Faulbaumrinde, Fenchel, Hagebuttenschalen, Huflattichblaettern

  16. [Soil humus differentiation and correlation with other soil biochemical properties in pure forests in semi-arid low-hilly area of Inner Mongolia, China].

    Science.gov (United States)

    Zhang, Xiao-Xi; Liu, Zeng-Wen; Bing, Yuan-Hao; Zhu, Bo-Chao; Huang, Liang-Jia

    2014-10-01

    Whether the content and composition of soil humus in pure forest change due to its simple component of litter and specificity of single-species dominant community is a key problem for forest sustainable management. In this study, soils from 6 kind of pure forests in semi-arid low-hilly area of Inner Mongolia were collected and their humus and other biochemical properties were measured to investigate the differentiation of soil humus and the impact factors. The results showed that the soil of Picea asperata and Betula platyphylla pure forests had the highest contents of humus and better condensation degrees and stabilities, followed by that of Populus simonii, Larix principis-rupprechtii and Ulmus pumila pure forests, while the soil of Pinus tabuliformis pure forest had the lowest content of humus, condensation degree and stability. There were significant positive correlations between soil microorganism biomass, activity of phosphatase and the content and stability of soil humus. In contrast, the soil peroxidate, dehydrogenase activity and soil humus content showed significant negative correlations with each other. Furthermore, the enhancement of dehydrogenase activity might decrease the stability of humus. There were significant positive correlations between available N and the content and stability of soil humus, but total Cu, Zn and Fe had negative correlations with them, and total Cu and Fe might reduce the stability of humus as well. The particularity of pure forest environment and litter properties might be the key inducement to soil humus differentiation, thus reforming the pure forest through mixing with other tree species or planting understory vegetation would be the fundamental way to improve the soil humus composition and stability. PMID:25796887

  17. Diversity and distribution of macrofungi in the Eastern Himalayan ecosystem

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    Prakash Pradhan

    2016-04-01

    Full Text Available Background: Eastern Himalayas have rich biodiversity but are threatened by anthropogenic activities and periodic natural calamities. The present investigation focused on the cryptogamic group of macrofungi in the Darjeeling Himalayas which are extremely diverse and ecologically significant, but have received very little attention from a conservation perspective. Materials and Methods: Investigations were conducted during June-September of 2013-2014 in the Darjeeling district of West Bengal, India, wherein, local macrofungi were sampled in mixed to monoculture forests using 50 random transects 100×2 m. Fruit bodies were studied, collected, identified in the laboratory and deposited at Calcutta University Herbarium. Sampling units were georeferenced and physico-climatic factors were derived from the WORLDCLIM database. Results: The macrofungi belonged to 98 species representing 72 genera and 47 families; 58.16% were saprotrophs, 17.34% were ectomycorrhizal and 10.2% were parasitic. The most species-rich families were Russulaceae with 9 Russula species followed by Marasmiaceae with 4 Marasmius species and Coprinaceae with 3 Coprinus species. Most of the ectomycorrhizal macrofungi were hosted by natural stands of Quercus, Lithocarpus and Betula. The only species with zooparasitic capability were Cordyceps nutans and C. militaris. The relative abundance of only 6 saprotrophs communicatively accounted for 52.84% of the total abundance. Conclusion: The findings showed that this region is rich in macrofungal diversity intricately linked to the functioning of the local ecosystem. However, a high proportion of saprotrophs compared to ectomycorrhizal species suggests disturbance and degradation of regional forests. Mycofloristically important localities like Lolaygaon, Sonada, and Lameydhura in the Darjeeling district should be prioritized for further studies and future conservation action.

  18. Radioactive caesium in Boreal forest landscapes - Dynamics and transport in food webs. Summary of research 1986-1996

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, R.; Nylen, T.; Palo, T

    1998-12-01

    The need for - but also the paucity of - radioecological knowledge concerning the boreal forest became particularly apparent after the nuclear power plant accident in Chernobyl in April 1986. As a consequence several new projects were initiated in the Nordic countries with particular focus on the behaviour of radioactivecaesium in terrestrial and aquatic systems characteristic for the Fenno-Scandinavian landscapes. Among these new projects a multi-disciplinary co-operation in Umeaa between scientists at the Swedish University of Agricultural Sciences, and the Defence Research Establishment emerged. Initially this joint work focused mainly on descriptions of the dynamic changes of the content of radioactive caesium in soil-plant and animal communities in the county of Vaesterbotten. Most of the studies have been performed at the Vindeln experimental forest, 60 km NW of Umeaa. Plants of key interest were: bilberry (Vaccinium myrtillus), birch (Betula spp.), and pine (Pinus sylvestris), and among the animals: the moose (Alces alces) and a small rodent, the forest vole (Clethrionomus glareolus). Gradually over the past ten years the research has entered the stage where the specific causes of the caesium behaviour have been addressed - partly by the help of models developed for simulating forest ecosystems, partly by complementary field experiments. This paper reviews our main findings on this theme concerning the behaviour of radioactive caesium in boreal landscapes and significant pathways to man, as has become apparent from the radioecological co-operation dating from about ten years back. A list of the publications arising from these studies since 1986 is also presented in this report.

  19. Phenological modelling: Can spatial data substitute temporal data?

    Science.gov (United States)

    Jochner, Susanne; Caffarra, Amelia; Menzel, Annette

    2014-05-01

    Not only long-term information, but also urbanisation gradients may be supportive to assess phenological responses to global warming. A substitution of phenological data collected over a longer period with data collected over a spatial gradient might be appropriate if plant phenology responds to climate change over time similarly as climate variability over space. However, the inherent methodological, spatial and temporal peculiarities of different data sources could hinder generalisations. We investigated whether phenological responses of birch (Betula pendula Roth) assessed by temperature variations are comparable over time and space and whether spatially calibrated models can predict long-term phenological data adequately. Therefore, we used flowering data sampled along urbanisation gradients in Germany in 2010 and 2011 and long-term data (1991-2010) in Bavaria. These data was explored using linear regression models based on mean temperature as well as process-based models (DORMPHOT model) incorporating forcing and chilling temperatures and photoperiod. A time-for-space substitution might not always be suitable since models calibrated on spatial data were only found to be useful to predict spatial data, but not to predict long-term data. This finding was also confirmed by a comparison of temperature response rates. The temperature response derived from spatial data (-4.4 days/°C) was significantly higher than the response calculated from the long-term data (-1.9 days/°C). Furthermore, the predictive performance of the linear model was comparable to that of the DORMPHOT model. A possible explanation might be that the process-based DORMPHOT model also includes the description of the responses of trees to chilling and photoperiod and to their interaction, but there is not enough information in only two study years to adequately model this response. Consequently, models calibrated on spatial data cannot necessarily reflect changes that occur in phenological

  20. Treeline dynamics with climate change at Central Nepal Himalaya

    Science.gov (United States)

    Gaire, N. P.; Koirala, M.; Bhuju, D. R.; Borgaonkar, H. P.

    2013-10-01

    Global climate change has multidimensional impacts with several biological fingerprints, and treeline shifting in tandem with climate change is a widely observed phenomenon in various parts of the world. In Nepal several impacts of climate change on physical environments have been observed. However, studies on the biological impacts are lacking. This dendrochronological study was carried out at the treeline ecotone (3750-4003 m a.s.l.) in the Kalchuman Lake (Kal Tal) area of the Manaslu Conservation Area in central Nepal Himalaya with the aim to study the dynamic impact of climate change at the treeline. The study provides an insight into regeneration and treeline dynamics over the past 200 yr. Two belt transect plots (size: 20 m wide, >250 m long) were laid covering forest line, treeline as well as tree species Abies spectabilis and Betula utilis was done and their tree-cores were collected. Stand character and age distribution revealed an occurrence of more matured B. utilis (max. age 198 yr old) compared to A. spectabilis (max. age 160 yr). A. spectabilis contained an overwhelmingly high population (89%) of younger plants (climate change and much wider differences anticipated in their population status as climate continues to cha spectabilis correlated negatively with the mean monthly temperature of May-August of the current year and with September of the previous year. The regeneration of A. spectabilis, on the other hand, was positively related with May-August precipitation and January-April temperature of the current year. The reconstructed average summer temperature (May-August) using tree ring data revealed alternate period of cool and warm period with warming in the 2nd half of the 20th century. Further palynological and geochronological studies of sediments of the Kalchuman Lake would advance our understanding of past climatic trends and dynamics of the associated treeline and vegetation in the area.

  1. Effects of extreme spring temperatures on phenology: a case study from Munich and Ingolstadt

    Science.gov (United States)

    Jochner, Susanne; Menzel, Annette

    2010-05-01

    Extreme events - e.g. warm spells or heavy precipitation events - are likely to increase in the future both in frequency and intensity. Therefore, research on extreme events gains new importance; also in terms of plant development which is mostly triggered by temperatures. An arising question is how plants respond to an extreme warm spell when following an extreme cold winter season. This situation could be studied in spring 2009 in the greater area of Munich and Ingolstadt by phenological observations of flowering and leaf unfolding of birch (Betula pendula L.) and flowering of horse chestnut (Aesculus hippocastanum L.). The long chilling period of winter 2008 and spring 2009 was followed by an immediate strong forcing of flowering and leaf unfolding, especially for birch. This extreme weather situation diminished the difference between urban and rural dates of onset. Another important fact that could be observed in the proceeding period of December 2008 to April 2009 was the reduced temperature difference among urban and rural sites (urban heat island effect). Long-term observations (1951-2008) of the phenological network of the German Meteorological Service (DWD) were used to identify years with reduced urban-rural differences between onset times in the greater area of Munich in the past. Statistical analyses were conducted in order to answer the question whether the sequence of extreme warm and cold events leads to a decreased difference in phenological onset times or if this behaviour can be attributed to extreme warm springs themselves or to the decreased urban heat island effect which is mostly affected by general atmospheric circulation patterns.

  2. Chemometrics in biomonitoring: Distribution and correlation of trace elements in tree leaves.

    Science.gov (United States)

    Deljanin, Isidora; Antanasijević, Davor; Bjelajac, Anđelika; Urošević, Mira Aničić; Nikolić, Miroslav; Perić-Grujić, Aleksandra; Ristić, Mirjana

    2016-03-01

    The concentrations of 15 elements were measured in the leaf samples of Aesculus hippocastanum, Tilia spp., Betula pendula and Acer platanoides collected in May and September of 2014 from four different locations in Belgrade, Serbia. The objective was to assess the chemical characterization of leaf surface and in-wax fractions, as well as the leaf tissue element content, by analyzing untreated, washed with water and washed with chloroform leaf samples, respectively. The combined approach of self-organizing networks (SON) and Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) aided by Geometrical Analysis for Interactive Aid (GAIA) was used in the interpretation of multiple element loads on/in the tree leaves. The morphological characteristics of the leaf surfaces and the elemental composition of particulate matter (PM) deposited on tree leaves were studied by using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) detector. The results showed that the amounts of retained and accumulated element concentrations depend on several parameters, such as chemical properties of the element and morphological properties of the leaves. Among the studied species, Tilia spp. was found to be the most effective in the accumulation of elements in leaf tissue (70% of the total element concentration), while A. hippocastanum had the lowest accumulation (54%). After water and chloroform washing, the highest percentages of removal were observed for Al, V, Cr, Cu, Zn, As, Cd and Sb (>40%). The PROMETHEE/SON ranking/classifying results were in accordance with the results obtained from the GAIA clustering techniques. The combination of the techniques enabled extraction of additional information from datasets. Therefore, the use of both the ranking and clustering methods could be a useful tool to be applied in biomonitoring studies of trace elements. PMID:26748000

  3. Transpiration of urban trees and its cooling effect in a high latitude city

    Science.gov (United States)

    Konarska, Janina; Uddling, Johan; Holmer, Björn; Lutz, Martina; Lindberg, Fredrik; Pleijel, Håkan; Thorsson, Sofia

    2016-01-01

    An important ecosystem service provided by urban trees is the cooling effect caused by their transpiration. The aim of this study was to quantify the magnitude of daytime and night-time transpiration of common urban tree species in a high latitude city (Gothenburg, Sweden), to analyse the influence of weather conditions and surface permeability on the tree transpiration, and to find out whether tree transpiration contributed to daytime or nocturnal cooling. Stomatal conductance and leaf transpiration at day and night were measured on mature street and park trees of seven common tree species in Gothenburg: Tilia europaea, Quercus robur, Betula pendula, Acer platanoides, Aesculus hippocastanum, Fagus sylvatica and Prunus serrulata. Transpiration increased with vapour pressure deficit and photosynthetically active radiation. Midday rates of sunlit leaves ranged from less than 1 mmol m-2 s-1 ( B. pendula) to over 3 mmol m-2 s-1 ( Q. robur). Daytime stomatal conductance was positively related to the fraction of permeable surfaces within the vertically projected crown area. A simple estimate of available rainwater, comprising of precipitation sum and fractional surface permeability within the crown area, was found to explain 68 % of variation in midday stomatal conductance. Night-time transpiration was observed in all studied species and amounted to 7 and 20 % of midday transpiration of sunlit and shaded leaves, respectively. With an estimated night-time latent heat flux of 24 W m-2, tree transpiration significantly increased the cooling rate around and shortly after sunset, but not later in the night. Despite a strong midday latent heat flux of 206 W m-2, a cooling effect of tree transpiration was not observed during the day.

  4. Suitability of different pollen as alternative food for the predatory mite Amblyseius swirskii (Acari, Phytoseiidae).

    Science.gov (United States)

    Goleva, Irina; Zebitz, Claus P W

    2013-11-01

    , and A. hippocastanum and Betula pendula pollen is recommended to be used as dispersible pollen in greenhouses. PMID:23670826

  5. Drivers of Change in a 7300-Year Holocene Diatom Record from the Hemi-Boreal Region of Ontario, Canada.

    Science.gov (United States)

    Beck, Kristen K; Medeiros, Andrew S; Finkelstein, Sarah A

    2016-01-01

    A Holocene lake sediment record spanning the past 7300 years from Wishart Lake in the Turkey Lakes Watershed in the Hemi-Boreal of central Ontario, Canada, was used to evaluate the potential drivers of long-term change in diatom assemblages at this site. An analysis of diatom assemblages found that benthic and epiphytic taxa dominated the mid-Holocene (7300-4000 cal yr BP), indicating shallow, oligotrophic, circum-neutral conditions, with macrophytes present. A significant shift in diatom assemblages towards more planktonic species (mainly Cyclotella sensu lato, but also several species of Aulacoseira, and Tabellaria flocculosa) occurred ~4000 cal yr BP. This change likely reflects an increase in lake level, coincident with the onset of a more strongly positive moisture balance following the drier climates of the middle Holocene, established by numerous regional paleoclimate records. Pollen-inferred regional changes in vegetation around 4000 yrs BP, including an increase in Betula and other mesic taxa, may have also promoted changes in diatom assemblages through watershed processes mediated by the chemistry of runoff. A more recent significant change in limnological conditions is marked by further increases in Cyclotella sensu lato beginning in the late 19th century, synchronous with the Ambrosia pollen rise and increases in sediment bulk density, signaling regional and local land clearance at the time of Euro-Canadian settlement (1880 AD). In contrast to the mid-Holocene increase in planktonic diatoms, the modern increase in Cyclotella sensu lato likely indicates a response to land use and vegetation change, and erosion from the watershed, rather than a further increase in water level. The results from Wishart Lake illustrate the close connection between paleoclimate change, regional vegetation, watershed processes, and diatom assemblages and also provides insight into the controls on abundance of Cyclotella sensu lato, a diatom taxonomic group which has shown

  6. Inhibition of Cytosolic Phospholipase A2α (cPLA2α by Medicinal Plants in Relation to Their Phenolic Content

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    Eva Arnold

    2015-08-01

    Full Text Available The cytosolic phospholipase A2α(cPLA2α is one of the potential targets for anti-inflammatory drugs, since this enzyme plays a key role in the inflammation processes seen in health disorders, like asthma, allergic reactions, arthritis and neuronal diseases. In this study, cPLA2α inhibition by 43 methanol extracts from medicinal plants rich in polyphenols was determined. The eight most active extracts were derived from Ribes nigrum (IC50 of 27.7 μg/mL, Ononis spinosa (IC50 of 39.4 μg/mL, Urtica dioica (IC50 of 44.32 μg/mL, Betula sp. (IC50 of 58.02 μg/mL, Sanguisorba officinalis (IC50 of 76.25 μg/mL, Orthosiphon stamineus (IC50 of 78.83 μg/mL, Petasites hybridus (IC50 of 81.02 μg/mL and Tussilago farfara (IC50 of 123.28 μg/mL. Additionally, the antioxidant activities of these extracts were determined with the 2,2-diphenyl-1-picrylhydrazyl (DPPH assay and their phenolic content with the Folin–Ciocalteu reagent. Antioxidant activity showed a non-linear, positive correlation to the phenolic content, but no correlation of PLA2 inhibition with phenolic content could be established. This study provides evidence that cPLA2α may be a relevant target for anti-inflammatory agents.

  7. Tree encroachment dynamics in heathlands of north-west Italy: the fire regime hypothesis

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    Ascoli D

    2010-09-01

    Full Text Available Tree encroachment is one of the primary conservation issues in Calluna-heathlands, a priority habitat in Europe. Improving understanding of the ecological factors that trigger transitions to woodlands is key to developing strategies for heathlands management. The irrational use of fire has been recognized as one of the key factors that drives the loss of heathlands of north-west Italy. The effect of high frequency pastoral burning on the replacement of heathlands by grasslands has been documented by several studies. The relationship between fire and tree encroachment is less clear. The paper examines the effect of the fire regime on the encroachment of Populus tremula L. and Betula pendula Roth. in the heathland. The study was carried out at the Managed Nature Reserve of Vauda (7° 41’ E, 45° 13’ N, which includes one of the most valuable heathlands of north-western Italy. The experimental design consisted of analysing the age structure, dendrometric variables and the species composition of three aspen and birch stands, circular-shaped and isolated within the heathland matrix. From 1986 to 2009 all stands experienced the same fire regime due to pastoral burning. Wildfires of similar behaviour occurred in 1998, 2003 and 2008 and determined the stand structure observed in 2009. The results evidenced that fire acts as a catalyst not only for seedlings establishment, as previously documented, but also for woodland expansion in the heathland. After initial establishment, stands showed a concentric encroachment dynamic, mainly due to aspen root suckering after post-fire stem mortality, whose steps of expansion coincided with the return interval of wildfires. Moreover, aspen determined the loss of heathland characteristic species, whose relative abundances were inversely correlated to aspen density along a gradient from the stands centre to the surrounding heathland. The regulation of current burning practices by prescribed burning, integrated

  8. Forest tree seedlings may suffer from predicted future winters

    Science.gov (United States)

    Domisch, Timo; Repo, Tapani; Martz, Françoise; Rautio, Pasi

    2016-04-01

    Future climate scenarios predict increased precipitation and air temperatures, particularly at high latitudes, and especially so during winter, spring and autumn. However, soil temperatures are more difficult to predict, since they depend strongly on the insulating snow cover. Warm periods during winter can lead to thaw-freeze cycles and flooding, which again can result in the formation of ice layers, affecting soil properties, soil gas concentrations and the survival of tree seedlings. We conducted two laboratory experiments of 20 weeks duration each, simulating winter, spring and early summer, and imposed Scots pine (Pinus sylvestris L.) or downy birch (Betula pubescens Ehrh.) seedlings to four different winter scenarios: (1) ambient snow cover, (2) compressed snow and ice encasement, (3) frozen flood and (4) no snow. We estimated the stress that the seedlings experienced by means of gas exchange, chlorophyll fluorescence and determining above- and belowground biomass and carbohydrate contents, as well as measuring soil oxygen and carbon dioxide concentrations. The seedlings in the snow and compressed snow treatments survived until the end of the experiments, although only those covered with an ambient snow cover showed normal height growth and typical carbohydrate contents. The seedlings in the other treatments showed symptoms of dieback already during early spring and had almost completely died at the end of the experiment. Our results suggest the crucial significance of the protective snow cover, and that a missing soil cover or soil hypoxia and anoxia during winter can be lethal for seedlings, and that respiratory losses and winter desiccation of aboveground organs can further lead to the death of tree seedlings.

  9. Comparative measurements of transpiration and canopy conductance in two mixed deciduous woodlands differing in structure and species composition.

    Science.gov (United States)

    Herbst, Mathias; Rosier, Paul T W; Morecroft, Michael D; Gowing, David J

    2008-06-01

    Transpiration of two heterogeneous broad-leaved woodlands in southern England was monitored by the sap flux technique throughout the 2006 growing season. Grimsbury Wood, which had a leaf area index (LAI) of 3.9, was dominated by oak (Quercus robur L.) and birch (Betula pubescens L.) and had a continuous hazel (Corylus avellana L.) understory. Wytham Woods, which had an LAI of 3.6, was dominated by ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.) and had only a sparse understory. Annual canopy transpiration was 367 mm for Grimsbury Wood and 397 mm for Wytham Woods. These values were similar to those for beech (Fagus sylvatica L.) plantations in the same region, and differ from one another by less than the typical margin of uncertainty of the sap flux technique. Canopy conductance (g(c)), calculated for both woodlands by inverting the Penman-Monteith equation, was related to incoming solar radiation (R(G)) and the vapor pressure deficit (D). The response of g(c) to R(G) was similar for both forests. Both reference conductance (g(cref)), defined as g(c) at D=1 kPa, and stomatal sensitivity (-m), defined as the slope of the logarithmic response curve of g(c) to D, increased during the growing season at Wytham Woods but not at Grimsbury Wood. The -m/g(cref) ratio was significantly lower at Wytham Woods than at Grimsbury Wood and was insufficient to keep the difference between leaf and soil water potentials constant, according to a simple hydraulic model. This meant that annual water consumption of the two woodlands was similar despite different regulatory mechanisms and associated short-term variations in canopy transpiration. The -m/g(cref) ratio depended on the range of D under which the measurements were made. This was shown to be particularly important for studies conducted under low and narrow ranges of D. PMID:18381276

  10. Impacts of Invasive Pests on Forest Carbon and Nitrogen Dynamics

    Science.gov (United States)

    Lovett, G. M.; Crowley, K. F.

    2014-12-01

    Forests of the U.S. have been subject to repeated invasions of destructive insects and diseases imported from other continents. Like other disturbances, these pests can produce short-term ecosystem effects due to tree mortality, but unlike other disturbances, they often target individual species and therefore can cause long-term species change in the forest. Because tree species vary in their influence on carbon (C) and nitrogen (N) cycles, pest-induced species change can radically alter the biogeochemistry of a forest. In this paper we use both data and modeling to examine how pest-induced species change may alter the C and N cycling in forests of the eastern U.S. We describe a new forest ecosystem model that distinguishes individual tree species and allows species composition to shift over the course of the model run. Results indicate that the mortality of eastern hemlock (Tsuga canadensis) by hemlock woolly adelgid and its replacement by faster-growing species such as black birch (Betula lenta) will reduce forest floor C stocks but increase productivity as the birch become established. Decline of American beech (Fagus grandifolia) from beech bark disease and its replacement by sugar maple (Acer saccharum) is likely to decrease soil C storage and increase N leaching from the ecosystem. Responses to other invasive pests will also be discussed. The magnitude of these species-specific effects on C and N cycling is in many cases larger than direct effects expected from changes in climate and atmospheric N deposition, indicating that species change should be included in models that predict forest ecosystem function under future environmental conditions.

  11. Long-term deforestation in NW Spain: linking the Holocene fire history to vegetation change and human activities

    Science.gov (United States)

    Kaal, Joeri; Carrión Marco, Yolanda; Asouti, Eleni; Martín Seijo, Maria; Martínez Cortizas, Antonio; Costa Casáis, Manuela; Criado Boado, Felipe

    2011-01-01

    The Holocene fire regime is thought to have had a key role in deforestation and shrubland expansion in Galicia (NW Spain) but the contribution of past societies to vegetation burning remains poorly understood. This may be, in part, due to the fact that detailed fire records from areas in close proximity to archaeological sites are scarce. To fill this gap, we performed charcoal analysis in five colluvial soils from an archaeological area (Campo Lameiro) and compared the results to earlier studies from this area and palaeo-ecological literature from NW Spain. This analysis allowed for the reconstruction of the vegetation and fire dynamics in the area during the last ca 11 000 yrs. In the Early Holocene, Fabaceae and Betula sp. were dominant in the charcoal record. Quercus sp. started to replace these species around 10 000 cal BP, forming a deciduous forest that prevailed during the Holocene Thermal Maximum until ˜5500 cal BP. Following that, several cycles of potentially fire-induced forest regression with subsequent incomplete recovery eventually led to the formation of an open landscape dominated by shrubs (Erica sp. and Fabaceae). Major episodes of forest regression were (1) ˜5500-5000 cal BP, which marks the mid-Holocene cooling after the Holocene Thermal Maximum, but also the period during which agropastoral activities in NW Spain became widespread, and (2) ˜2000-1500 cal BP, which corresponds roughly to the end of the Roman Warm Period and the transition from the Roman to the Germanic period. The low degree of chronological precision, which is inherent in fire history reconstructions from colluvial soils, made it impossible to distinguish climatic from human-induced fires. Nonetheless, the abundance of synanthropic pollen indicators (e.g. Plantago lanceolata and Urtica dioica) since at least ˜6000 cal BP strongly suggests that humans used fire to generate and maintain pasture.

  12. Uses of tree saps in northern and eastern parts of Europe

    Directory of Open Access Journals (Sweden)

    Ingvar Svanberg

    2012-12-01

    Full Text Available In this article we review the use of tree saps in northern and eastern Europe. Published accounts by travellers, ethnologists and ethnobotanists were searched for historical and contemporary details. Field observations made by the authors have also been used. The presented data shows that the use of tree sap has occurred in most north and eastern European countries. It can be assumed that tree saps were most used where there were extensive stands of birch or maple trees, as these two genera generally produce the largest amount of sap. The taxa most commonly used have been Betula pendula, B. pubescens, and Acer platanoides, but scattered data on the use of several other taxa are presented. Tree sap was used as a fresh drink, but also as an ingredient in food and beverages. It was also fermented to make light alcoholic products like ale and wine. Other folk uses of tree saps vary from supplementary nutrition in the form of sugar, minerals and vitamins, to cosmetic applications for skin and hair and folk medicinal use. Russia, Ukraine, Belarus, Estonia, Latvia and Lithuania are the only countries where the gathering and use of sap (mainly birch sap has remained an important activity until recently, due to the existence of large birch forests, low population density and the incorporation of sap into the former Soviet economic system. It is evident that gathering sap from birch and other trees was more widespread in earlier times. There are records indicating extensive use of tree saps from Scandinavia, Poland, Slovakia and Romania, but it is primarily of a historical character. The extraction of tree sap in these countries is nowadays viewed as a curiosity carried out only by a few individuals. However, tree saps have been regaining popularity in urban settings through niche trading.

  13. Effects of atmospheric CO{sub 2}, light availability and tree species on the quality of leaf detritus as a resource for treehole mosquitoes

    Energy Technology Data Exchange (ETDEWEB)

    Strand, M.; Herms, D.A.; Walker, E.D.; Merritt, R.W. [Michigan State Univ., Dept. of Entomology, East Lansing, MI (United States); Ayres, M.P. [Dartmouth College, Dept. of Biological Sciences, Hanover, NH (United States); Kubiske, M.E.; Pregitzer, K.S. [Michigan Technological Univ., School of Forestry and Lake Superior Ecosystems Research Center, Houghton, MI (United States); Kaufman, M.G. [Michigan State Univ., W.K. Kellogg Biological Station, Hickory Corners, MI (United States)

    1999-07-01

    Elevated CO{sub 2} could alter the productivity of heterotrophic aquatic ecosystems through effects on allochthonous litter inputs. The effects of atmospheric CO{sub 2} concentration, light availability to trees and tree species, on leaf detritus quality as a food resource for eastern treehole mosquitoes (Aedes triseriatus) were examined. Larvae were reared in laboratory microcosms (simulated treeholes) with naturally-senesced, abscised foliage from seedlings of red oak (Quercus rubra) and paper birch (Betula papyrifera) grown in ambient and elevated atmospheric CO{sub 2} environments. Elevated CO{sub 2} did not have significant effects on any measure of mosquito performance. In contrast, host species and light availability had dramatic effects on mosquito development time and survival; light availability had additional effects on adult size. Mosquito reproductive potential ({+-} SE) averaged 8.4 {+-} 1.5 females female{sup -1}) generation{sup -1} when litter input was from birch-sun leaves, but was 19.6 {+-} 1.8 when the litter was from birch-shade leaves and 13.0 {+-} 1.8 when from oak-sun leaves. Mosquito development time was nearly halved when the litter input was from oak-sun leaves versus birch-sun leaves, suggesting a potential for even greater demographic effects (e.g. two generations per year instead of one could yield a 20-fold increase in annual growth rate). Trophic transfer rates (mg insect detritivore g litter{sup -1} d{sup -1}) were 3-fold greater on birch-shade leaves than on birch-sun leaves. Changes in insolation and tree species composition can have important consequences for forest ecosystems, because of effects on litter quality that impact microbial saprobes and, ultimately, invertebrate detritivores. (au)

  14. A cross-site comparison of factors influencing soil nitrification rates in northeastern USA forested watersheds

    Science.gov (United States)

    Ross, D.S.; Wemple, B.C.; Jamison, A.E.; Fredriksen, G.; Shanley, J.B.; Lawrence, G.B.; Bailey, S.W.; Campbell, J.L.

    2009-01-01

    Elevated N deposition is continuing on many forested landscapes around the world and our understanding of ecosystem response is incomplete. Soil processes, especially nitrification, are critical. Many studies of soil N transformations have focused on identifying relationships within a single watershed but these results are often not transferable. We studied 10 small forested research watersheds in the northeastern USA to determine if there were common factors related to soil ammonification and nitrification. Vegetation varied between mixed northern hardwoods and mixed conifers. Watershed surface soils (Oa or A horizons) were sampled at grid or transect points and analyzed for a suite of chemical characteristics. At each sampling point, vegetation and topographic metrics (field and GIS-based) were also obtained. Results were examined by watershed averages (n = 10), seasonal/watershed averages (n = 28), and individual sampling points (n = 608). Using both linear and tree regression techniques, the proportion of conifer species was the single best predictor of nitrification rates, with lower rates at higher conifer dominance. Similar to other studies, the soil C/N ratio was also a good predictor and was well correlated with conifer dominance. Unlike other studies, the presence of Acer saccharum was not by itself a strong predictor, but was when combined with the presence of Betula alleghaniensis. Topographic metrics (slope, aspect, relative elevation, and the topographic index) were not related to N transformation rates across the watersheds. Although found to be significant in other studies, neither soil pH, Ca nor Al was related to nitrification. Results showed a strong relationship between dominant vegetation, soil C, and soil C/N. ?? 2008 Springer Science+Business Media, LLC.

  15. Carbon budgets of three temperate forest ecosystems in Dongling Mt.,Beijing,China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    There is a general agreement that forest ecosystems in the Northern Hemisphere function as signifi-cant sinks for atmospheric CO2; however, their magnitude and distribution remain large uncertainties. In this paper, we report the carbon (C) stock and its change of vegetation, forest floor detritus, and mineral soil, annual net biomass increment and litterfall production, and respiration of vegetation and soils between 1992 to 1994, for three temperate forest ecosystems, birch (Betula platyphylla) forest, oak (Quercus liaotungensis) forest and pine (Pinus tabulaeformis) plantation in Mt. Dongling, Beijing, China. We then evaluate the C budgets of these forest ecosystems. Our results indicated that total C density (organic C per hectare) of these forests ranged from 250 to 300 t C ha-1, of which 35―54 t C ha-1 from vegetation biomass C and 209―244 t C ha-1 from soil organic C (1 m depth, including forest floor detritus). Biomass C of all three forests showed a net increase, with 1.33―3.55 t C ha-1 a-1 during the study period. Litterfall production, vegetation autotrophic respiration, and soil heterotrophic respira-tion were estimated at 1.63―2.34, 2.19―6.93, and 1.81―3.49 t C ha-1 a-1, respectively. Ecosystem gross primary production fluctuated between 5.39 and 12.82 t C ha-1 a-1, about half of which (46%―59%, 3.20―5.89 t C ha-1 a-1) was converted to net primary production. Our results suggested that pine forest fixed C of 4.08 t ha-1 a-1, whereas secondary forests (birch and oak forest) were nearly in balance in CO2 exchange between the atmosphere and ecosystems.

  16. Carbon budgets of three temperate forest ecosystems in Dongling Mt., Beijing, China

    Institute of Scientific and Technical Information of China (English)

    FANG JingYun; LIU GuoHua; ZHU Biao; WANG XiaoKe; LIU ShaoHui

    2007-01-01

    There is a general agreement that forest ecosystems in the Northern Hemisphere function as significant sinks for atmospheric CO2; however, their magnitude and distribution remain large uncertainties. In this paper, we report the carbon (C) stock and its change of vegetation, forest floor detritus, and mineral soil, annual net biomass increment and litterfall production, and respiration of vegetation and soils between 1992 to 1994, for three temperate forest ecosystems, birch (Betula platyphylla) forest, oak (Quercus liaotungensis) forest and pine (Pinus tabulaeformis) plantation in Mt. Dongling, Beijing, China. We then evaluate the C budgets of these forest ecosystems. Our results indicated that total C density (organic C per hectare) of these forests ranged from 250 to 300 t C ha-1, of which 35―54 t C ha-1 from vegetation biomass C and 209―244 t C ha-1 from soil organic C (1 m depth, including forest floor detritus). Biomass C of all three forests showed a net increase, with 1.33―3.55 t C ha-1 a-1 during the study period. Litterfall production, vegetation autotrophic respiration, and soil heterotrophic respiration were estimated at 1.63―2.34, 2.19―6.93, and 1.81―3.49 t C ha-1 a-1, respectively. Ecosystem gross primary production fluctuated between 5.39 and 12.82 t C ha-1 a-1, about half of which (46%―59%, 3.20―5.89 t C ha-1 a-1) was converted to net primary production. Our results suggested that pine forest fixed C of 4.08 t ha-1 a-1, whereas secondary forests (birch and oak forest) were nearly in balance in CO2 exchange between the atmosphere and ecosystems.

  17. Growth responses of Picea mongolica seedlings to defoliation rate

    Institute of Scientific and Technical Information of China (English)

    ZOU Chun-jing; HAN Shi-jie; QI Shu-yan; XU Wen-duo; LI Dao-tang

    2005-01-01

    Picea mongolica W. D. Xu. is an endemic species in China. The spruce forest is only found in semi-arid habitat in Inner Mongolia Autonomous Region of China. Based on the simulative defoliation experiment, it was proved that Picea mongolica seedlings had the compensatory and overcompensatory effects under the certain defoliation rate. The results of variance analysis on growth indexes showed that in PM Ⅰ (natural regeneration seedlings under Picea mongolica forest), the differences of H1 (height in June 23) and H2 (height in September 3) were extremely significant, and the difference of D(diameter at the breast height) were not significant. In PM Ⅱ (artificial regeneration seedlings under Betula platyphylla Suk. forest), the difference of H1 was significant, the difference of H2 was not significant, and the difference of D was extremely significant. The regression equations were established and the compensatory and overcompensatory points were obtained. In PM Ⅰ , the compensatory points of H1, H2, and D were 0.7628, 0.7436, 0.5725, and the overcompensatory points were 0.6056, 0.5802 and 0.2909 respectively. In PM Ⅱ, the compensatory points of H1, H2, and D are 0.5012, 0.3421, 0.2488, and the overcompensatory points are 0.4137, 0.2633 and 0.0747 respectively. These results suggested that the induction of compensatory growth mechanisms in spruce seedlings required a threshold level of defoliation, and the insects in Picea mongolica forest could be controlled in a certain degree.

  18. Evaluation of the allergenicity potential of TcPR-10 protein from Theobroma cacao.

    Directory of Open Access Journals (Sweden)

    Sara Pereira Menezes

    Full Text Available BACKGROUND: The pathogenesis related protein PR10 (TcPR-10, obtained from the Theobroma cacao-Moniliophthora perniciosa interaction library, presents antifungal activity against M. perniciosa and acts in vitro as a ribonuclease. However, despite its biotechnological potential, the TcPR-10 has the P-loop motif similar to those of some allergenic proteins such as Bet v 1 (Betula verrucosa and Pru av 1 (Prunus avium. The insertion of mutations in this motif can produce proteins with reduced allergenic power. The objective of the present work was to evaluate the allergenic potential of the wild type and mutant recombinant TcPR-10 using bioinformatics tools and immunological assays. METHODOLOGY/PRINCIPAL FINDINGS: Mutant substitutions (T10P, I30V, H45S were inserted in the TcPR-10 gene by site-directed mutagenesis, cloned into pET28a and expressed in Escherichia coli BL21(DE3 cells. Changes in molecular surface caused by the mutant substitutions was evaluated by comparative protein modeling using the three-dimensional structure of the major cherry allergen, Pru av 1 as a template. The immunological assays were carried out in 8-12 week old female BALB/c mice. The mice were sensitized with the proteins (wild type and mutants via subcutaneous and challenged intranasal for induction of allergic airway inflammation. CONCLUSIONS/SIGNIFICANCE: We showed that the wild TcPR-10 protein has allergenic potential, whereas the insertion of mutations produced proteins with reduced capacity of IgE production and cellular infiltration in the lungs. On the other hand, in vitro assays show that the TcPR-10 mutants still present antifungal and ribonuclease activity against M. perniciosa RNA. In conclusion, the mutant proteins present less allergenic potential than the wild TcPR-10, without the loss of interesting biotechnological properties.

  19. CO2 elevation improves photosynthetic performance in progressive warming environment in white birch seedlings [v1; ref status: indexed, http://f1000r.es/up

    Directory of Open Access Journals (Sweden)

    Shouren Zhang

    2013-01-01

    Full Text Available White birch (Betula paperifera Mash seedlings were exposed to progressively warming in greenhouses under ambient and elevated CO2 concentrations for 5 months to explore boreal tree species’ potential capacity to acclimate to global climate warming and CO2 elevation. In situ foliar gas exchange, in vivo carboxylation characteristics and chlorophyll fluorescence were measured at temperatures of 26oC and 37oC. Elevated CO2 significantly increased net photosynthetic rate (Pn at both measurement temperatures, and Pn at 37oC was higher than that at 26oC under elevated CO2. Stomatal conductance (gs was lower at 37oC than at 26oC, while transpiration rate (E was higher at 37oC than that at 26oC. Elevated CO2 significantly increased instantaneous water-use efficiency (WUE at both 26oC and 37oC, but WUE was markedly enhanced at 37oC under elevated CO2. The effect of temperature on maximal carboxylation rate (Vcmax, PAR-saturated electron transport rate (Jmax and triose phosphate utilization (TPU varied with CO2, and the Vcmax and Jmax were significantly higher at 37oC than at 26oC under elevated CO2. However, there were no significant interactive effects of CO2 and temperature on TPU. The actual photochemical efficiency of PSII (DF/ Fm’, total photosynthetic linear electron transport rate through PSII (JT and the partitioning of JT to carboxylation (Jc were higher at 37oC than at 26oC under elevated CO2. Elevated CO2 significantly suppressed the partitioning of JT to oxygenation (Jo/JT. The data suggest that the CO2 elevation and progressive warming greatly enhanced photosynthesis in white birch seedlings in an interactive fashion.

  20. New insights in postglacial paleoclimatic and paleoenvironmental changes in Central Europe derived from isotope analyses of laminated lake sediments and peat deposits

    International Nuclear Information System (INIS)

    Isotope ratio determinations in concert with geochemical and palynological analyses performed on material from German continental archives (lake sediments, peat cores) provided information about paleoclimatic and paleoenvironmental changes in Central Europe throughout the last 15,000 years. Oxygen isotope ratio variations of (i) bulk carbonates from lake sediments (Lake Steisslingen) and of (ii) cellulose extracted from peat cores suggest the following climatic trends: an early postglacial climate optimum in the Boelling; a distinct cooling phase during the Younger Dryas; an early Holocene warming period in the Preboreal; another warming phase in the Boreal leading into the mid-Holocene warm period; a gradual decrease of mean annual air temperatures since the mid- Holocene warm period. Evaluation of other isotopic proxy data in concert with geochemical and palynological information revealed that the above-described climatic variations in Central Europe triggered marked paleoenvironmental changes in the study region between the Boelling and the onset of the mid-Holocene warm period. Elevated organic carbon contents in lake sediments and increasing δ13C values of organic carbon were typically associated with climatic warm phases and seem to indicate enhanced in-lake productivity. Pollen counts and biomarker data suggest a predominance of Betula during climatic warm phases and a predominance of Pinus during colder periods. The Mid Younger Dryas event was observable in pollen and biomarker data, but oxygen isotope ratios of bulk carbonates from Lake Steisslingen did not record temperature variations at that time. The data presented for the chronozones Bolling through Boreal provide evidence that the elucidation of paleoclimatic and paleoenvironmental variations on our continents can benefit greatly from a joint interpretation of isotope analyses, palynological evidence, and inorganic and organic geochemistry data derived from continental archives. (author)

  1. An ecological approach to the assessment of vegetation cover on inactive uranium mill tailings sites

    International Nuclear Information System (INIS)

    Vascular plants have been collected from abandoned or inactive uranium mill tailings in three mining areas in Canada. The collection was evaluated to determine some characteristics of vegetation development and to identify the plants which will persist on the sites. A total of 170 species were identified. Many of the species are widely distributed in North America, none has been reported as rare in any of the locations from which they were collected. Species richness was highest on Bancroft sites and lowest on Uranium City sites, though values were variable between sites. Forty-four per cent of the total number of species were found on only a single site. Only seven species occurred on more than half of the tailings sites and in all three mining areas. There was no difference between amended and unamended sites in terms of either species richness or species composition. There was no apparent relationship between species richness and either site size, site age or amendment history. The results of this survey suggest that the uranium mill tailings sites are at an early stage of colonization where the seed input from surrounding areas and the heterogeneity of the sites are factors determining species composition and species richness. The fate of an individual once it has reached the site will be determined by its ability to establish on the sites. A perennial growth habit and the ability to expand clonally are important characteristics of the species on the tailings. The species on the tailings are commonly found in a variety of habitats. Consistent with the observation that the tailings sites are at a stage of early colonization, we find that the few species widely distributed across sites are all characteristic pioneering species with wide environmental tolerances. These species included Populus tremuloides, P. balsamifera, Scirpus cyperinus, Equisetum arvense, Betula papyrifera, Achillea millefolium and Typha spp. The vegetation on the tailings is likely to be

  2. NMR analysis of the human saliva metabolome distinguishes dementia patients from matched controls.

    Science.gov (United States)

    Figueira, João; Jonsson, Pär; Nordin Adolfsson, Annelie; Adolfsson, Rolf; Nyberg, Lars; Öhman, Anders

    2016-07-19

    Saliva is a biofluid that is sensitive to metabolic changes and is straightforward to collect in a non-invasive manner, but it is seldom used for metabolite analysis when studying neurodegenerative disorders. We present a procedure for both an untargeted and targeted analysis of the saliva metabolome in which nuclear magnetic resonance (NMR) spectroscopy is used in combination with multivariate data analysis. The applicability of this approach is demonstrated on saliva samples selected from the 25 year prospective Betula study, including samples from dementia subjects with either Alzheimer's disease (AD) or vascular dementia at the time of sampling or who developed it by the next sampling/assessment occasion five years later, and age-, gender-, and education-matched control individuals without dementia. Statistically significant multivariate models were obtained that separated patients with dementia from controls and revealed seven discriminatory metabolites. Dementia patients showed significantly increased concentrations of acetic acid (fold change (fc) = 1.25, p = 2 × 10(-5)), histamine (fc = 1.26, p = 0.019), and propionate (fc = 1.35, p = 0.002), while significantly decreased levels were observed for dimethyl sulfone (fc = 0.81, p = 0.005), glycerol (fc = 0.79, p = 0.04), taurine (fc = 0.70, p = 0.007), and succinate (fc = 0.62, p = 0.008). Histamine, succinate, and taurine are known to be important in AD, and acetic acid and glycerol are involved in related pathways. Dimethyl sulfone and propionate originate from the diet and bacterial flora and might reflect poorer periodontal status in the dementia patients. For these seven metabolites, a weak but statistically significant pre-diagnostic value was observed. Taken together, we present a robust and general NMR analysis approach for studying the saliva metabolome that has potential use for screening and early detection of dementia. PMID:27265744

  3. Contribution of Soil Fauna to Foliar Litter-Mass Loss in Winter in an Ecotone between Dry Valley and Montane Forest in the Upper Reaches of the Minjiang River.

    Directory of Open Access Journals (Sweden)

    Yan Peng

    Full Text Available Litter decomposition during winter can provide essential nutrients for plant growth in the subsequent growing season, which plays important role in preventing the expansion of dry areas and maintaining the stability of ecotone ecosystems. However, limited information is currently available on the contributions of soil fauna to litter decomposition during winter in such ecosystems. Therefore, a field experiment that included litterbags with two different mesh sizes (0.04 mm and 3 mm was conducted to investigate the contribution of soil fauna to the loss of foliar litter mass in winter from November 2013 to April 2014 along the upper reaches of the Minjiang River. Two litter types of the dominant species were selected in each ecosystem: cypress (Cupressus chengiana and oak (Quercus baronii in ecotone; cypress (Cupressus chengiana and clovershrub (Campylotropis macrocarpa in dry valley; and fir (Abies faxoniana and birch (Betula albosinensis in montane forest. Over one winter incubation, foliar litter lost 6.0%-16.1%, 11.4%-26.0%, and 6.4%-8.5% of initial mass in the ecotone, dry valley and montane forest, respectively. Soil fauna showed obvious contributions to the loss of foliar litter mass in all of the ecosystems. The highest contribution (48.5%-56.8% was observed in the ecotone, and the lowest contribution (0.4%-25.8% was observed in the montane forest. Compared with other winter periods, thawing period exhibited higher soil fauna contributions to litter mass loss in ecotone and dry valley, but both thawing period and freezing period displayed higher soil fauna contributions in montane forest. Statistical analysis demonstrated that the contribution of soil fauna was significantly correlated with temperature and soil moisture during the winter-long incubation. These results suggest that temperature might be the primary control factor in foliar litter decomposition, but more active soil fauna in the ecotone could contribute more in litter

  4. The added value of biomarker analysis to the genesis of plaggic Anthrosols; the identification of stable fillings used for the production of plaggic manure

    Science.gov (United States)

    van Mourik, Jan M.; Wagner, Thomas V.; Geert de Boer, J.; Jansen, Boris

    2016-07-01

    Plaggic Anthrosols are the result of historical forms of land management in cultural landscapes on chemically poor sandy substrates. Application of plaggic manure was responsible for the development of the plaggic horizons of these agricultural soils. Pollen diagrams reflect aspects of the environmental development but the interpretation of the pollen spectra is complicated due to the mix of the aeolian pollen influx of crop species and species in the surroundings, and of pollen occurring in the used stable fillings. Pollen diagrams and radiocarbon dates of plaggic Anthrosols suggested a development period of more than a millennium. Calluna is present in almost all the pollen spectra, indicating the presence of heath in the landscape during the whole period of soil development. Optically stimulated luminescence dating of the plaggic horizon made clear that the deposition of plaggic covers started in the 16th century and accelerated in the 18th century. The stable fillings, used for the production of plaggic manure and responsible for the rise of the soil surface, cannot be identified with pollen diagrams alone. Biomarker analyses provide more evidence about the sources of stable fillings. The oldest biomarker spectra of the plaggic horizons of three typical plaggic Anthrosols examined in this study were dominated by biomarkers of forest species such as Quercus and Betula while the spectra of middle part of the plaggic horizons were dominated by biomarkers of stem tissue of crop species such as Secale and Avena. Only the youngest spectra of the plaggic horizons were dominated by biomarkers of Calluna. This indicates that the use of heath sods as stable filling was most likely introduced very late in the development of the Anthrosols. Before the 19th century the mineral component in plaggic manure cannot be explained by the use of heath sods. We conclude that other sources of materials, containing mineral grains must have been responsible for the raise of the plaggic

  5. Investigations on structure and function of the Betv1-gene family

    International Nuclear Information System (INIS)

    Bet v 1, the major allergen of birch (Betula verrucose) and Cor a 1, the major allergen of hazel (Corylus avellana) are related to one family of pathogenesis related proteins. Thus the structure and function of these molecules is relevant for allergen research as well as for the biology of the pollen itself. Naturally occurring Bet v 1 from pollen (nBet v 1) shows heterogeneity when analyzed by 2-D gel electrophoresis, which could suggest that modifications take place posttranslationally. In this thesis, it was demonstrated by RP-HPLC and mass spectrometry that various sequence isoforms of nBet v 1 are expressed in pollen. With the exception of cleavage of the N-terminal methionine residue further postsynthetic modifications were not found. The same results were obtained for recombinantly expressed Bet v 1a. In addition, the presence of three isoforms of Cor a 1 in pollen could be demonstrated by the same methods. Again, the N-terminal methionine was absent in this protein. Yet, interestingly, C-terminal asparagine was partly desamidated in Cor a 1. This could be due to the existence of a fourth isoform or to a posttranslational modification. Bet v 1 shares sequence similarity with a RNase of Ginseng panax and, therefore, the activity of RNases in birch pollen wash-outs was characterized. However, Bet v 1 exhibits no such, activity. A further aim of this thesis has been the characterization of novel allergens. Cofactor independent phosphoglycerate mutase of higher plants was found to be a highly conserved plant allergen. It was purified and molecularly cloned. (author)

  6. Quantifying Age-Related Hydraulic and Biochemical Constraints on Tree Photosynthesis in the Southern Appalachian Mountains

    Science.gov (United States)

    Missik, J.; Benson, M. C.; Oishi, A. C.; Novick, K. A.; Miniat, C.

    2015-12-01

    Forest carbon accumulation generally declines with age, a trend largely attributed to reductions in gross primary production (GPP). However, for many species, uncertainty remains about the specific mechanisms limiting GPP. We examine both tree hydraulic and biochemical parameters affecting carbon uptake across a successional gradient in the southern Appalachian Mountains, utilizing a chronosequence approach with 5-, 10-, and 85-year old forest stands. We conducted measurements on four of the dominant species in the region: Liriodendron tulipifera, Betula lenta, Acer rubrum, and Quercus alba. To assess biochemical photosynthetic capacity, we estimated Vcmax and Jmax from over 140 gas exchange A/Ci curves. We determined that leaf gas exchange measurements performed on excised branches of A. saccharum, L. tulipifera, and Q. alba significantly underestimated assimilation by 35, 26, and 63% on average, respectively. Therefore, A/Ci measurements were performed on in situ canopy branches, using an 18 m boom lift to access the tallest trees. We examine how these photosynthetic parameters vary with age, height, and foliar nitrogen content among tree species and canopy positions. In order to investigate hydraulic factors driving stomatal behavior and therefore carbon uptake, we collected measurements of mid-day and pre-dawn leaf water potential (ψmd and ψpd) and xylem cavitation vulnerability. Preliminary results suggest that ψmd-ψpd decreases with along the chronosequence in anisohydric species, whereas ψmd-ψpd increases or remains stable with age/height in isohydric species. These data will be analyzed together with site- and species-specific hydraulic vulnerability data to assess whether the hydraulic safety margin changes with tree age/height, and explore how these patterns vary among species representing different xylem anatomies and a range of isohydric/anisohydric water management strategies. These results will provide improved estimates of common parameters in

  7. Are low altitude alpine tundra ecosystems under threat? A case study from the Parc National de la Gaspésie, Québec

    International Nuclear Information System (INIS)

    According to the 2007 IPCC report, the alpine tundra ecosystems found on low mountains of the northern hemisphere are amongst the most threatened by climate change. A treeline advance or a significant erect shrub expansion could result in increased competition for the arctic-alpine species usually found on mountaintops and eventually lead to their local extinction. The objectives of our study were to identify recent changes in the cover and growth of erect woody vegetation in the alpine tundra of Mont de la Passe, in the Parc National de la Gaspésie (Québec, Canada). The comparison of two orthorectified aerial photos revealed no significant shift of the treeline between 1975 and 2004. During the same period however, shrub species cover increased from 20.2% to 30.4% in the lower alpine zone. Dendrochronological analyses conducted on Betula glandulosa Michx. sampled at three different positions along an altitudinal gradient (low, intermediate and high alpine zone) revealed that the climatic determinants of B. glandulosa radial growth become more complex with increasing altitude. In the lower alpine zone, B. glandulosa radial growth is only significantly associated positively to July temperature. In the intermediate alpine zone, radial growth is associated positively to July temperature but negatively to March temperature. In the high alpine zone, radial growth is positively associated to January, July and August temperature but negatively to March temperature. The positive association between summer temperatures and radial growth suggests that B. glandulosa could potentially benefit from warmer temperatures, a phenomenon that could lead to an increase in its cover over the next few decades. Although alpine tundra vegetation is not threatened in the short-term in the Parc National de la Gaspésie, erect shrub cover, especially B. glandulosa, could likely increase in the near future, threatening the local arctic-alpine flora. (letter)

  8. High-performance liquid chromatographic determination of arbutin in skin-whitening creams and medicinal plant extracts.

    Science.gov (United States)

    Thongchai, Wisanu; Liawruangrath, Boonsom; Liawruangrath, Saisunee

    2007-01-01

    A high-performance liquid chromatographic method was developed for quantitative analysis of arbutin. The arbutin was separated on an ODS Hypersil C(18) column with a mobile phase of water:methanol:0.1 M hydrochloric acid (89:10:1, v/v/v). The level of arbutin was measured by means of UV detection at 222 nm. The optimum conditions for arbutin quantitative analysis were investigated. The calibration curve was found to be linear up to 1,000 microg/ml(-1) of arbutin concentration, and the working calibration curve for arbutin determination over the range 0.5-30.0 microg/ml(-1) of arbutin (r(2)=0.9999) was established. The relative standard deviations for intraday and interday were found to be 0.98% and 1.15%, respectively. A detection limit (3sigma) and quantitation limit (10sigma) of 0.02 microg/ml(-1) and 0.2 microg/ml(-1), respectively, and a mean percentage recovery of the spiked arbutin of 99.88 +/- 1.12% were obtained. The proposed method has been applied to the determination of arbutin in commercial skin-whitening creams (Arbuwhite cream, Super Whitening cream, and Shiseido cream) with average contents of 7.60, 5.30, and 57.90 mg/g(-1), respectively. It was also applied to the determination of arbutin in medicinal plant extracts from Betula alnoides Buch. Ham., Clerodendrum petasites S. Moore, Curculigo latifolia Dryand. Var. latifolia, and Hesperethusa crenulata (Roxb.) Roem, levels of which were found to be 3.50, 1.50, 1.10, and 0.12 microg/g(-1), respectively (no article reported in the literature about arbutin analysis). The proposed HPLC method is rapid, simple, and selective for routine analysis. PMID:17342266

  9. РЕДКИЕ И ОХРАНЯЕМЫЕ ВИДЫ РАСТЕНИЙ В ЛУЖСКОМ РАЙОНЕ ЛЕНИНГРАДСКОЙ ОБЛАСТИ

    OpenAIRE

    Конечная, Галина; Шипилина, Лилия

    2013-01-01

    В статье приводятся результаты инвентаризации редких и охраняемых растений, а также проверки ранее указанных мест их обитания в Лужском районе Ленинградской области. Указаны новые местонахождения: для трех видов из Красной книги РФ (Cypripedium calceolus L., Liparis loeselii (L.) Rich, Orchis ustulata L.), для 16 видов из Красной книги природы Ленинградской области (Betula humilis Schrank., Carex hartmanii Cajand., C. paniculata L., Coeloglossum viride (L.) С. Hartm., Dentaria bulbifera L., F...

  10. Recent expansion of erect shrubs in the Low Arctic: evidence from Eastern Nunavik

    International Nuclear Information System (INIS)

    In order to characterize shrub response near the treeline in Eastern Nunavik (Québec), a region under extensive warming since the 1990s, we compared two series (1964 and 2003) of vertical aerial photos from the vicinity of Kangiqsualujjuaq. Our study revealed a widespread increase in erect woody vegetation cover. During the 40 years spanning the two photo series, erect shrub and tree cover increased markedly on more than half of the land surface available for new colonization or infilling. Within the 7.2 km2 analysed, areas with dense shrub and tree cover (>90%) increased from 34% to 44% whereas areas with low cover (<10%) shrank from 45% to 29%. This increase in cover of trees and shrubs occurred throughout the landscape regardless of altitude, slope angle and exposure, although to varying extents. The main shrub species involved in this increase was Betula glandulosa Michx. (dwarf birch), which was present in 98% and dominant in 85% of the 345 plots. In addition, numerous seedlings and saplings of Larix laricina (Du Roi) K Koch (eastern larch) were found above the treeline (25% of the plots), suggesting that the altitudinal treeline might shift upslope in the near future. Sites that remained devoid of erect woody vegetation in 2003 were either characterized by the absence of a suitable seedbed or by harsh local microclimatic conditions (wind exposure or excessive drainage). Our results indicate dramatic increases in shrub and tree cover at a Low Arctic site in Eastern Nunavik, contributing to a growing number of observations of woody vegetation change from various areas around the North. (letter)

  11. Water use and carbon exchange of red oak- and eastern hemlock-dominated forests in the northeastern USA: implications for ecosystem-level effects of hemlock woolly adelgid.

    Science.gov (United States)

    Hadley, Julian L; Kuzeja, Paul S; Daley, Michael J; Phillips, Nathan G; Mulcahy, Thomas; Singh, Safina

    2008-04-01

    Water use and carbon exchange of a red oak-dominated (Quercus rubra L.) forest and an eastern hemlock-dominated (Tsuga canadensis L.) forest, each located within the Harvard Forest in north-central Massachusetts, were measured for 2 years by the eddy flux method. Water use by the red oak forest reached 4 mm day(-1), compared to a maximum of 2 mm day(-1) by the eastern hemlock forest. Maximal carbon (C) uptake rate was also higher in the red oak forest than in the eastern hemlock forest (about 25 versus 15 micromol m(-2) s(-1)). Sap flux measurements indicated that transpiration of red oak, and also of black birch (Betula lenta L.), which frequently replaces eastern hemlock killed by hemlock woolly adelgid (Adelges tsugae Annand.), were almost twice that of eastern hemlock. Despite the difference between species in maximum summertime C assimilation rate, annual C storage of the eastern hemlock forest almost equaled that of the red oak forest because of net C uptake by eastern hemlock during unusually warm fall and spring weather, and a near-zero C balance during the winter. Thus, the effect on C storage of replacing eastern hemlock forest with a forest dominated by deciduous species is unclear. Carbon storage by eastern hemlock forests during fall, winter and spring is likely to increase in the event of climate warming, although this may be offset by C loss during hotter summers. Our results indicate that, although forest water use will decrease immediately following eastern hemlock mortality due to the hemlock woolly adelgid, the replacement of eastern hemlock by deciduous species such as red oak will likely increase summertime water use over current rates in areas where hemlock is a major forest species. PMID:18244947

  12. Understanding the effects of intermediate disturbances on evapotranspiration in the upper Midwest

    Science.gov (United States)

    Frasson, R.; Bohrer, G.; Frasson, C. D.; Kenny, W.; Maurer, K.; Ivanov, V. Y.; Vogel, C.; Walko, R. L.; Medvigy, D.; Curtis, P.

    2012-12-01

    Following heavy disturbances in the 19th and early 20th centuries, an even aged, aspen-dominated canopy flourished in certain areas of the upper Midwest of the U.S., such as the forest surrounding the University of Michigan Biological Station (UMBS). Currently, the dominant early successional species are either reaching maturity or beginning to decline. As aspen (textit{Populus spp.}) and birch (textit{Betula papyrifera}) are senescing, they are replaced by red maple (textit{Acer rubrum}), northern red oak (textit{Quercus rubra}), and white pine (textit{Pinus strobus}) leading to a more structurally diverse canopy. Despite conventional conceptual models suggesting declining rates of net carbon sequestration for aging forests, recent empirical studies at our site point to a higher-than-expected carbon storage rate. The Forest Accelerated Succession ExperimenT (FASET), in which aspen and birch were girdled in an area of 39 ha, provides an invaluable opportunity to study how carbon and water vapor fluxes vary as the canopy recovers from intermediate disturbance. By comparing water vapor and carbon fluxes in the undisturbed UMBS-AmeriFlux location with the fluxes measured in the FASET site, we aim to better understand how succession affects transpiration and carbon sequestration. In this work, we utilized the Ocean-Land-Atmosphere-Model (OLAM) to study how latent heat flux, as a proxy for evapotranspiration, responds to changes in the vegetation. We ran two scenarios, namely undisturbed and girdled. In the second configuration we modified vegetation parameters inside the FASET site to reflect the effects of the birch and aspen removal. Finally we compared simulation results with measurements obtained at both undisturbed UMBS-AmeriFlux site and at FASET. As a result of this study, we expect to improve the understanding of the role of canopy structure on evapotranspiration of broadleaved deciduous forests.

  13. Volatile organic compounds emitted from silver birch of different provenances across a latitudinal gradient in Finland.

    Science.gov (United States)

    Maja, Mengistu M; Kasurinen, Anne; Holopainen, Toini; Kontunen-Soppela, Sari; Oksanen, Elina; Holopainen, Jarmo K

    2015-09-01

    Climate warming is having an impact on distribution, acclimation and defence capability of plants. We compared the emission rate and composition of volatile organic compounds (VOCs) from silver birch (Betula pendula (Roth)) provenances along a latitudinal gradient in a common garden experiment over the years 2012 and 2013. Micropropagated silver birch saplings from three provenances were acquired along a gradient of 7° latitude and planted at central (Joensuu 62°N) and northern (Kolari 67°N) sites. We collected VOCs emitted by shoots and assessed levels of herbivore damage of three genotypes of each provenance on three occasions at the central site and four occasions at the northern site. In 2012, trees of all provenances growing at the central site had higher total VOC emission rates than the same provenances growing at the northern site; in 2013 the reverse was true, thus indicating a variable effect of latitude. Trees of the southern provenance had lower VOC emission rates than trees of the central and northern provenances during both sampling years. However, northward or southward translocation itself had no significant effect on the total VOC emission rates, and no clear effect on insect herbivore damage. When VOC blend composition was studied, trees of all provenances usually emitted more green leaf volatiles at the northern site and more sesquiterpenes at the central site. The monoterpene composition of emissions from trees of the central provenance was distinct from that of the other provenances. In summary, provenance translocation did not have a clear effect in the short-term on VOC emissions and herbivory was not usually intense at the lower latitude. Our data did not support the hypothesis that trees growing at lower latitudes would experience more intense herbivory, and therefore allocate resources to chemical defence in the form of inducible VOC emissions. PMID:26093370

  14. Permanent vegetation quadrats on Olkiluoto island. Establishment and results from the first inventory

    International Nuclear Information System (INIS)

    This report describes in detail the vegetation quadrats established inside the permanent, follow-up sample plots (Forest Extensive High-level monitoring plots, FEH) on Olkiluoto Island. During summer 2005 a total of 94 sample plots (a 30 m2), each containing eight quadrats (a 1m2), were investigated. The total number of sampled quadrats was 752. Seventy of the 94 plots represent coniferous stands: 57 Norway spruce-dominated and 13 Scots pine-dominated stands. Ten of the plots represent deciduous, birch-dominated (Betula spp.) stands, 7 plots common alder-dominated (Alnus glutinosa) stands, and seven plots are mires. The majority of the coniferous tree stands were growing on sites representing various succession stages of the Myrtillus, Vaccinium-Myrtillus and Deschampsia-Myrtillus forest site types. The pine-dominated stands growing on exposed bedrock clearly differed from the other coniferous stands: the vegetation was characterised by the Cladina, Calluna-Cladina and Empetrum-Vaccinium vitis-idaea/Vaccinium Myrtillus forest site types. The deciduous stands were characterized by tall grasses, especially Calamagrostis epigejos, C. purpurea and Deschampsia flexuosa. The vegetation of the deciduous stands dominated by common alder represented grove-like sites and seashore groves. Typical species for mires included Calamagrostis purpurea, Calla palustris, Equisetum sylvaticum, and especially white mosses (Sphagnum spp.). A total of 184 vascular plant species were found growing within the quadrats. Due to the high number of quadrats in these forests, the spruce stands had the highest total number of species, but the birch and alder-dominated forests had the highest average number of species per quadrat. This basic inventory of the permanent vegetation quadrats on Olkiluoto Island provides a sound starting point for future vegetation surveys. Guidelines for future inventories and supplementary sampling are given in the discussion part of this report. (orig.)

  15. The effect of increased air humidity on northern deciduous forest ecosystem - a FAHM study.

    Science.gov (United States)

    Ostonen, Ivika; Rosenvald, Katrin; Tullus, Arvo; Parts, Kaarin; Sellin, Arne; Kupper, Priit; Sõber, Jaak; Sõber, Anu; Uri, Veiko; Aosaar, Jürgen; Varik, Mats; Lõhmus, Krista

    2013-04-01

    At northern latitudes a rise in atmospheric humidity and precipitation is predicted as a consequence of global climate change. In 2006 an unique experimental facility for free air humidity manipulation (FAHM) was established in Estonia to study the functioning of deciduous forest ecosystem under altered humidity conditions. The experimental site contains humidified and control plots, each includes four types of forest ecosystem: two overstorey species (planted hybrid aspen (Populus tremula L. × P. tremuloides Michx. and silver birch (Betula pendula Roth.)) both split into two types according to understorey vegetation (diverse "forest" understory and early successional grasses). We investigated the productivity, biomass allocation and functioning of silver birch forest ecosystem in response to elevated atmospheric humidity (on average 7% over the ambient level) during four growing seasons (2008-2011). We hypothesized that elevated air humidity facilitates both above- and below-ground growth and accumulation of plant biomass. During the first three experimental seasons height, stem diameter, and stem volume (D2H) increments of trees, biomass of understory in aboveground and fine root biomass in belowground were similar or significantly reduced in humidified plots. Only the fine root and rhizome biomass of the understory was twice higher in humidified plots. However, fine root turnover speeded up for both tree and understory roots. The trends in above-ground growth changed in 2011, when current annual increments of trees height, diameter, stem volume and fine root biomass were higher in humidified plots. Functionally, trees hydraulic conductance was significantly higher and stem sap flux lower for humidified trees coinciding with significantly higher biomass of primary (in majority ectomycorrhizal) roots, morphologically thinner and longer root tips and higher specific root length. Humidification caused a shift in the root tips colonizing fungal community towards the

  16. Characteristics of T-cell and B-cell immune respoonses to pollen allergens in Bulgarian patients with pollinosis

    Directory of Open Access Journals (Sweden)

    ZHIVKA KOSTOVA

    2015-12-01

    Full Text Available Characterization of the pollen allergens and identification of the main T-cell and B-cell epitopes is of crucial importance, since the clarification of the cellular and molecular mechanisms will allow long-term control of this type allergic diseases and development of safe immunotherapeutic medication. The objective of this study was to identify which pollen allergens are responsible for the T-cell activation in atopic patients with pollinosis and to determine whether the same allergens are responsible for the IgE-mediated reactions. Thirty-seven patients with pollinosis and thirteen non-allergic subjects were recruited. Peripheral blood samples were collected out of the pollen season. T-cell responses (IFN-γ production towards different pollen allergens and levels of pollen specific IgE and IgG in the sera were measured by ELISA. The T-cell reactivity in most patients was directed towards the grass pollen B1, tree pollen I and autumn pollen B5. 70% of the allergic individuals responded to allergens from Lolium perenne, 84% to Dactylis glomerata, 11% to Phleum pratense, 65% to Betula pendula and 70% to Taxus baccata. Elevated serum levels of specific IgE in the allergic patients (p<0.01 were measured against the tree pollen I and autumn pollen, which include widespread deciduous trees (birch, willow, poplar and yew and Artemisia absinthium, respectively. Our results show that the T-cell reactivity and antibody responses may be directed towards different or the same allergens. In addition, we propose that short synthetic peptides, which contain overlapping T- and B-cell epitopes can be used for specific immunotherapy treatment if they lack antibody recognition domains.

  17. Development and in-house validation of an allergen-specific ELISA for quantification of Bet v 4 in diagnostic and therapeutic birch allergen products.

    Science.gov (United States)

    Dehus, Oliver; Zimmer, Julia; Döring, Sascha; Führer, Frank; Hanschmann, Kay-Martin; Holzhauser, Thomas; Neske, Florian; Strecker, Daniel; Trösemeier, Jan-Hendrik; Vieths, Stefan; Kaul, Susanne

    2015-02-01

    Birch (Betula) pollen is a major cause of allergy in northern and central Europe. The allergenic potency of products for diagnosis and therapy of birch pollen allergy is adjusted nearly exclusively to the major birch pollen allergen Bet v 1. Although every fifth patient is additionally sensitized to Bet v 4, both content and variability of this minor allergen in birch allergen products remain unclear due to a lack of simple and cost-effective quantitative methods. This study aimed to develop and in-house validate the first Bet v 4-specific sandwich enzyme-linked immunosorbent assay (ELISA). Based on a murine monoclonal antibody in combination with a polyclonal rabbit antiserum, the ELISA proved to be highly sensitive, with a lower limit of quantification of 30 pg/ml Bet v 4. After confirmation of satisfactory accuracy, reproducibility, and robustness, the ELISA was utilized to quantify Bet v 4 in 30 authorized birch allergen products. The allergen was detected in all samples tested, ranging from 0.2 to 4.4 μg/ml. No significant correlation of Bet v 4 was found with the respective amount of Bet v 1. In contrast to Bet v 1, also no correlation of Bet v 4 with total protein content or total allergenic activity could be observed. Thus, it seems presently unfeasible to base birch allergen product standardization additionally on Bet v 4. In light of these results, the continuous monitoring of Bet v 4 in birch allergen products with the presented ELISA will provide a basis for the understanding of the clinical relevance of minor allergens. PMID:25572690

  18. Synthesis of siderophores by plant-associated metallotolerant bacteria under exposure to Cd(2.).

    Science.gov (United States)

    Złoch, Michał; Thiem, Dominika; Gadzała-Kopciuch, Renata; Hrynkiewicz, Katarzyna

    2016-08-01

    Rhizosphere and endophytic bacteria are well known producers of siderophores, organic compounds that chelate ferric iron (Fe(3+)), and therefore play an important role in plant growth promotion in metalliferous areas, thereby improving bioremediation processes. However, in addition to their primary function in iron mobilization, siderophores also have the capacity to chelate other heavy metals, such as Al(3+), Zn(2+), Cu(2+), Pb(2+) and Cd(2+), that can affect homeostasis and the heavy metal tolerance of microorganisms. The main goal of our study was to select the most efficient siderophore-producing bacterial strains isolated from the roots (endophytes) and rhizosphere of Betula pendula L. and Alnus glutinosa L. growing at two heavy metal contaminated sites in southern Poland. Siderophore biosynthesis of these strains in the presence of increasing concentrations of Cd(2+) (0, 0.5, 1, 2 and 3 mM) under iron-deficiency conditions was analysed using spectrophotometric chemical tests for hydroxamates, catecholates and phenolates, as well as the separation of bacterial siderophores by HPLC and characterization of their structure by UHPLC-QTOF/MS. We proved that (i) siderophore-producing bacterial strains seems to be more abundant in the rhizosphere (47%) than in root endophytes (18%); (ii) the strains most effective at siderophore synthesis belonged to the genus Streptomyces and were able to secrete three types of siderophores under Cd(2+) stress: hydroxamates, catecholates and phenolates; (iii) in general, the addition of Cd(2+) enhanced siderophore synthesis, particularly ferrioxamine B synthesis, which may indicate that siderophores play a significant role in tolerance to Cd(2+) in Streptomyces sp. PMID:27183333

  19. Integration of BpMADS4 on various linkage groups improves the utilization of the rapid cycle breeding system in apple.

    Science.gov (United States)

    Weigl, Kathleen; Wenzel, Stephanie; Flachowsky, Henryk; Peil, Andreas; Hanke, Magda-Viola

    2015-02-01

    Rapid cycle breeding in apple is a new approach for the rapid introgression of agronomically relevant traits (e.g. disease resistances) from wild apple species into domestic apple cultivars (Malus × domestica Borkh.). This technique drastically shortens the long-lasting juvenile phase of apple. The utilization of early-flowering apple lines overexpressing the BpMADS4 gene of the European silver birch (Betula pendula Roth.) in hybridization resulted in one breeding cycle per year. Aiming for the selection of non-transgenic null segregants at the end of the breeding process, the flower-inducing transgene and the gene of interest (e.g. resistance gene) that will be introgressed by hybridization need to be located on different chromosomes. To improve the flexibility of the existing approach in apple, this study was focused on the development and characterization of eleven additional BpMADS4 overexpressing lines of four different apple cultivars. In nine lines, the flowering gene was mapped to different linkage groups. The differences in introgressed T-DNA sequences and plant genome deletions post-transformation highlighted the unique molecular character of each line. However, transgenic lines demonstrated no significant differences in flower organ development and pollen functionality compared with non-transgenic plants. Hybridization studies using pollen from the fire blight-resistant wild species accession Malus fusca MAL0045 and the apple scab-resistant cultivar 'Regia' indicated that BpMADS4 introgression had no significant effect on the breeding value of each transgenic line. PMID:25370729

  20. 山西霍山白桦种群不同龄级立木的点格局分析

    Institute of Scientific and Technical Information of China (English)

    何艳华; 闫明; 武丽君; 张直峰; 毕润成

    2011-01-01

    以山西霍山地区的先锋树种之一白桦(Betula platyphylla)为研究对象,在霍山七里峪林场典型地段设置一个50 m×50 m的样方,应用点格局分析方法对其不同龄级(Ⅰ级、Ⅱ级、Ⅲ级和Ⅳ级)个体的分布格局及相互关系进行了研究。结果表明:(1)白桦种群不同龄级的个体间密度也不相同,中间龄级Ⅱ级(7 cm〈DBH≤14 cm)和Ⅲ级(14 cm〈DBH≤21 cm)的密度较大,幼龄和老龄个体密度小,年龄结构为衰退型;(2)除Ⅰ级(DBH≤7 cm)外,其余3个龄级集群分布特征比较明显,且随着龄级的增加,集群特征有更明显的趋势;(3)除Ⅰ级和Ⅱ级、Ⅱ级和Ⅲ级、Ⅱ级和Ⅳ级(DBH〉21 cm)之外,其余龄级间基本都是小尺度下负关联,并随尺度的增大关联性逐渐变得不显著。

  1. Biological and Physical Drivers of Coarse Woody Debris Respiration Following Moderate Forest Disturbance

    Science.gov (United States)

    Schmid, A. V.; Franklin, R. B.; Vogel, C. S.; Liebman, E.; Curtis, P.; Gough, C. M.

    2014-12-01

    Forest disturbances that cause plant mortality alter the net carbon (C) balance by increasing heterotrophic respiration associated with coarse woody debris (CWD) decomposition. Whether a forest transitions from a C sink to source following disturbance is largely a function of the quantity of additional CWD produced and the rate of woody debris decomposition. Coarse woody debris temperature, moisture, and microbial community composition are known to drive rates of heterotrophic respiration, but rarely have these factors been studied together across a gradient of wood decay and over time following disturbance. We used a large-scale experimental disturbance, in which early successional aspen (Populus spp.) and birch (Betula papyrifera) were killed via stem girdling within a 39 ha area, to study the effects of moderate disturbance on the forest C cycle. We quantified changes over time in CWD mass for a decade, before and after disturbance. We then conducted point measurements of CWD respiration, temperature and moisture, and quantified extracellular enzyme activity of enzymes associated with wood decomposition for five classes varying in extent of decay and standing woody debris. Process and inventory data are being used to estimate ecosystem CO2 efflux from CWD, which we will contrast with net ecosystem production (NEP) determined from long-term eddy covariance measurements of net CO2 exchange between the forest and atmosphere at the University of Michigan Biological Station (US-UMd) Ameriflux site. Our results will improve ecosystem model predictions of CWD respiration by incorporating both physical factors, such as temperature and wood moisture content, and biological factors, such as extracellular enzymatic activity of different functional types of decomposers.

  2. Heavy metals in reindeer and their forage plants

    Directory of Open Access Journals (Sweden)

    O. Eriksson

    1990-09-01

    Full Text Available An attempt was made to assess the level of heavy metal transfer from forage plants to reindeer (Rangifer tarandus L. in an area in northern Lapland affected from dust from an open pit copper mine. Botanical analyses of rumen contents from reindeer provided information about the main plant species in the diet. Representative plant material was collected from sample plots within an 8 km radius from the central part of the mine and from a reference area situated about 200 km upwind of the mining site. The following plant species were analysed: Bryoria jremontii, Br. juscescens, Cladina rangiferina, Equisetum fluviatile, Descbampsiaflexuosa, Eriopborum vaginatum, Salix glauca, Salix pbylicifolia, Betula nana, and Vaccini-um myrtillus. The greatest difference between metal concentrations in the plants collected from dust contaminated area and from the reference area was found in lichens. Copper is the main metallic component of the ore and was found in higher concentrations in lichens coming from the area around the mine than in lichens from the reference area. Smaller differences were found in vascular plants. Dust particles, remaining on outer surfaces after snow smelt contributed to a limited extent to the metal contents. Species—specific accumulation of metals was observed in some plants. The uptake of lead and cadmium in some vascular plants was somewhat higher in the reference area compared with plants growing in the perifery of the mining center, probably due to the metal concentrations in the bedrock. Organ material (liver and kidney was collected from reindeer in both areas. No noticable effect on metal concentrations in the liver of the reindeer were found. Although the lead, cadmium and copper concentrations were higher in the organs collected from animals in the reference area than in those from the mining area, the levels were still below the concentrations regarded as harmful for the animals from toxicological point of view. The

  3. Late Glacial and Holocene Paleoenvironmental Change Recorded in Lake Sediments, Brock Plateau (Melville Hills), Northwest Territories, Canada

    Science.gov (United States)

    Ruhland, K.; St. Jacques, J.; Beierle, B. D.; Lamoureux, S. F.; Dyke, A. S.; Smol, J. P.

    2009-05-01

    Sediments from South Lake, Brock Plateau (Melville Hills), Northwest Territories, provide one of the longest postglacial records from the mainland western Canadian Arctic, outside of eastern Beringia. Sedimentation commenced at least 13,900 cal yr B.P., possibly as early as 15,000 cal yr B.P. in response to early deglaciation of the site. Pollen is present throughout the entire record, with an initial Artemisia-Salix assemblage indicative of very cold conditions, consistent with a locally severe Younger Dryas Stade (~12,700-11,500 cal yr B.P.). At ~11,000 cal yr B.P., abiotic proxies signal a transition to warmer conditions, which is confirmed by a pollen shift to an assemblage dominated by Betula and Cyperaceae. Although South Lake was biologically productive during the early Holocene (~11,000-7,000 cal yr B.P.), diatoms and other siliceous organisms are notably absent from the record, suggesting severe silica limitation. Rises in Alnus crispa and Picea mariana pollen at ~7500 cal yr B.P. suggest cooling and/or an increase in effective moisture. Following this vegetation change, wetter conditions likely led to the establishment of a pioneering diatom community at ~6500 cal yr B.P. as a result of increased hydrological inputs and thus, the silica supply. Decreased organic sedimentation after 2000 cal yr B.P. suggests cooler conditions. Additionally, changing niveo-eolian deposition of sand on lake ice varied with a ~3000-year periodicity through the entire record. The long South Lake pollen record lends support to the hypothesis that the Brock Plateau was one of the earliest deglaciated regions, if not an actual nunatak during the late Wisconsinan.

  4. Vegetation of the Central Beringian Lowlands: Evidence of a Glacial Refugium Found in IODP Expedition 323 Sediment

    Science.gov (United States)

    Westbrook, R.; Fowell, S. J.; Bigelow, N. H.; VanLaningham, S.

    2011-12-01

    The lowlands of central Beringia may have acted as a glacial refugium for boreal vegetation, which expanded into eastern and western Beringia as climate changed and glaciers retreated. Persistence of trees, shrubs and mesic-adapted vegetation in the vicinity of the modern Bering Strait and Bering Sea Shelf could have presented a barrier to migrating fauna during Pleistocene glacial stages. These hypotheses have been difficult to test, because sampling has been restricted to lacustrine sediment and peat deposits accessible in eastern and western Beringia. Pollen analysis of cores from IODP Expedition 323 (Bering Sea Expedition) sites U1339 and U1343, on the edge of the Bering Sea Shelf, permits reconstruction of the terrestrial vegetation of adjacent south-central Beringia. Palynological assemblages extracted from sediment that accumulated during Marine Isotope Stages 2 and 6 are dominated by grass (Poaceae ≥ 15%) and sedge (Cyperaceae ≥ 20%). Spruce (Picea ≥ 5%), birch (Betula ≥ 10%) and alder (Alnus ≥ 5%) are also consistently present throughout glacial/interglacial cycles, suggesting that small populations of trees and shrubs remained in central Beringia during glacial maxima. These results support the refugium hypothesis. Although it is possible that some of the boreal plant pollen deposited during glacial stages is derived from interglacial sediment reworked by rivers flowing across the emergent shelf, we postulate that such sources only contribute about 1-5% of the total sediment found at these Bering slope sites. Thus we consider the palynological assemblages from IODP Expedition 323 a robust proxy for the glacial vegetation of central Beringia.

  5. Plant community responses to 5 years of simulated climate change in meadow and heath ecosystems at a subarctic-alpine site.

    Science.gov (United States)

    Jägerbrand, Annika K; Alatalo, Juha M; Chrimes, Dillon; Molau, Ulf

    2009-09-01

    Climate change was simulated by increasing temperature and nutrient availability in an alpine landscape. We conducted a field experiment of BACI-design (before/after control/impact) running for five seasons in two alpine communities (heath and meadow) with the factors temperature (increase of ca. 1.5-3.0 degrees C) and nutrients (5 g N, 5 g P per m(2)) in a fully factorial design in northern Swedish Lapland. The response variables were abundances of plant species and functional types. Plant community responses to the experimental perturbations were investigated, and the responses of plant functional types were examined in comparison to responses at the species level. Nutrient addition, exclusively and in combination with enhanced temperature increase, exerted the most pronounced responses at the species-specific and community levels. The main responses to nutrient addition were increases in graminoids and forbs, whereas deciduous shrubs, evergreen shrubs, bryophytes, and lichens decreased. The two plant communities of heath or meadow showed different vegetation responses to the environmental treatments despite the fact that both communities were located on the same subarctic-alpine site. Furthermore, we showed that the abundance of forbs increased in response to the combined treatment of temperature and nutrient addition in the meadow plant community. Within a single-plant functional type, most species responded similarly to the enhanced treatments although there were exceptions, particularly in the moss and lichen functional types. Plant community structure showed BACI responses in that vegetation dominance relationships in the existing plant functional types changed to varying degrees in all plots, including control plots. Betula nana and lichens increased in the temperature-increased enhancements and in control plots in the heath plant community during the treatment period. The increases in control plots were probably a response to the observed warming during

  6. How reproducible are the measurements of leaf fluctuating asymmetry?

    Directory of Open Access Journals (Sweden)

    Mikhail V. Kozlov

    2015-06-01

    Full Text Available Fluctuating asymmetry (FA represents small, non-directional deviations from perfect symmetry in morphological characters. FA is generally assumed to increase in response to stress; therefore, FA is frequently used in ecological studies as an index of environmental or genetic stress experienced by an organism. The values of FA are usually small, and therefore the reliable detection of FA requires precise measurements. The reproducibility of fluctuating asymmetry (FA was explored by comparing the results of measurements of scanned images of 100 leaves of downy birch (Betula pubescens conducted by 31 volunteer scientists experienced in studying plant FA. The median values of FA varied significantly among the participants, from 0.000 to 0.074, and the coefficients of variation in FA for individual leaves ranged from 25% to 179%. The overall reproducibility of the results among the participants was rather low (0.074. Variation in instruments and methods used by the participants had little effect on the reported FA values, but the reproducibility of the measurements increased by 30% following exclusion of data provided by seven participants who had modified the suggested protocol for leaf measurements. The scientists working with plant FA are advised to pay utmost attention to adequate and detailed description of their data acquisition protocols in their forthcoming publications, because all characteristics of instruments and methods need to be controlled to increase the quality and reproducibility of the data. Whenever possible, the images of all measured objects and the results of primary measurements should be published as electronic appendices to scientific papers.

  7. Effects of chronic radiation exposure on small mammals in the Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    The Chernobyl reactor accident in April 1986 caused the release to atmosphere of some 2 x 106 TBq, or more, of total fission/activation products. Estimates of deposition vary, although it is probable that about half the activity was deposited within 20 km of the release point, predominantly following two plume trajectories to the north and west. This resulted in the death of pine trees over 400 ha, the abandonment of up to 150 000 ha of agricultural land and the establishment of an exclusion zone extending to 30 km from the site. High levels of radionuclide contamination continue to prevail within the exclusion zone. Nonetheless, recolonisation has been widespread. Mixed deciduous woodlands, with a high proportion of birch (Betula spp.) and willow (Salix spp.), have become established in the forest areas, while agricultural land has succeeded to tall grassland and scrub. Field sites investigated in this study, during 2001-2003, exhibited external gamma dose rates varying from 0.1 μSv h-1 to 140 μSv h-1. Corresponding mean concentrations of 137Cs in the top 20 cm of soil varied from about 6 x 102 to 3 x 106 Bq kg-1 dw (dry weight). Little impact is evident on populations of small mammals in these areas, either for species diversity or overall abundance, although there is a slight (not statistically significant) trend for increasing spleen weight in the bank vole with increasing levels of contamination. Previous suggestions that populations contain a preponderance of juveniles and sub-adults at the highest contaminated sites are not supported. (author)

  8. Macroscale intraspecific variation and environmental heterogeneity: analysis of cold and warm zone abundance, mortality, and regeneration distributions of four eastern US tree species.

    Science.gov (United States)

    Prasad, Anantha M

    2015-11-01

    I test for macroscale intraspecific variation of abundance, mortality, and regeneration of four eastern US tree species (Tsuga canadensis,Betula lenta,Liriodendron tulipifera, and Quercus prinus) by splitting them into three climatic zones based on plant hardiness zones (PHZs). The primary goals of the analysis are to assess the differences in environmental heterogeneity and demographic responses among climatic zones, map regional species groups based on decision tree rules, and evaluate univariate and multivariate patterns of species demography with respect to environmental variables. I use the Forest Inventory Analysis (FIA) data to derive abundance, mortality, and regeneration indices and split the range into three climatic zones based on USDA PHZs: (1) cold adapted, leading region; (2) middle, well-adapted region; and (3) warm adapted, trailing region. I employ decision tree ensemble methods to assess the importance of environmental predictors on the abundance of the species between the cold and warm zones and map zonal variations in species groups. Multivariate regression trees are used to simultaneously explore abundance, mortality, and regeneration in tandem to assess species vulnerability. Analyses point to the relative importance of climate in the warm adapted, trailing zone (especially moisture) compared to the cold adapted, leading zone. Higher mortality and lower regeneration patterns in the warm trailing zone point to its vulnerability to growing season temperature and precipitation changes that could figure more prominently in the future. This study highlights the need to account for intraspecific variation of demography in order to understand environmental heterogeneity and differential adaptation. It provides a methodology for assessing the vulnerability of tree species by delineating climatic zones based on easily available PHZ data, and FIA derived abundance, mortality, and regeneration indices as a proxy for overall growth and fitness. Based on

  9. Variability in diet composition and dynamics of radiocaesium in moose

    International Nuclear Information System (INIS)

    1. Moose is the most important game species in Sweden and the fall-out after the Chernobyl accident has severely affected hunting of this animal. Nine years after the accident many animals in areas that received high deposition still show activity concentrations that exceed the limit for human consumption. Whilst the mechanism for uptake of 137Cs in animals is fairly well known, the extent of variability in diet composition in wild animals is still puzzling and our ability to predict future trends in activity concentration of radionuclides limited. Studies on moose since the Chernobyl accident reveal considerable variation in 137Cs-transfer between years and between individuals even in the same area. Differences in diet composition among individuals may explain the high degree of observed variability. Seventy per cent of the diet of moose in September is composed of Vaccinium myrtillus, Betula spp. and Salix spp. Significant differences between the proportion of birch and other components and species diversity within the diets among some years were measured. 2. We used a simple model, applying Monte Carlo simulations to create artificial diets for 137Cs intake in moose. The model suggests that changes of diet composition or habitat use are the main reasons for the large variation of 137Cs observed in moose. The variability in activity concentrations between different years obscure the decline expected from physical decay. The model shows that the standard deviation of 137Cs activity concentration in moose meat declines with time as differences in activity concentration between food plants diminish. The coefficient of variation varies considerably among years in the real population and the model suggests that even at comparatively low mean values a large variation between individuals is expected. The model predicts that even after 30 years, the half-life of 137Cs, a high mean level and a large variation could be possible

  10. Benthic fauna of extremely acidic lakes (pH 2-3)

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, G.G.

    2001-07-01

    The structure of the benthic invertebrate communities were investigated in terms of composition, abundance, and biomass from extremely acidic lakes with pH values from 2 to 3 in areas where coal was intensively mined in the Lusatian region in the eastern region of Germany. Benthic invertebrates colonisation on leaves and the breakdown rate processing of the three deciduous leaf: Betula pendula (birch), Fraxinus excelsior (ash), and Juglans regia (walnut) were investigated. Also, the main key-species of these acidic environments were investigated, in terms of description of pupal exuviae of Chironomus crassimanus and the feeding habit of this acid-resistant species through analysis of their gut content. The benthic food web in extremely acidic mining Lusatian lakes is very short in terms of species richness, trophic relationship, guilds and functional feeding groups. Collector-filters and scraper-grazers were absent in extremely acidic mining lakes (AML 107, AML 111 and AML 117). Shredders as Limnophyes minimus (Diptera, Chironomidae, Orthocladiinae) and Hydrozetes lacustris (Acari, Hydrozetidae) occurred in low abundance in AML 107 and AML 111, and it may be in response to slow leaf breakdown process in these ecosystems, except in AML 117 where the H. lacustris contributed most to ecosystems functioning via the processing of litter. Aquatic insects as Sialis lutaria (Megaloptera, Sialidae), Orectochilus villosus (Coleoptera, Gyrinidae), Coenagrion mercuriale (Odonata, Coenagrionidae), and Phryganeidae (Trichoptera) are the top-predators of these ecosystems. They did not depend on the level of pH in the lakes, but on the availability of food resources. (orig.)

  11. The saproxylic beetle assemblage associated with different host trees in Southwest China

    Institute of Scientific and Technical Information of China (English)

    Jie Wu; Xiao-Dong Yu; Hong-Zhang Zhou

    2008-01-01

    Dead wood is a habitat for many insects and other small animals,some of which may be rare or endangered and in need of effective protection.In this paper,saproxylic beetle assemblages associated with different host trees in the subtropical forests in southwestern China were investigated.A total of 277 species (1 439 specimens) in 36 beetle families were collected from 117 dead wood samples,of which 101 samples were identified and respectively belonged to 12 tree genera.The number of saproxylic beetle species varied greatly among logs of different tree genera,with the highest diversity on logs of Juglans.Generally,broad-leaved trees had a higher richness and abundance of saproxylic species than coniferous trees.Cluster analysis revealed that assemblages from broad-leaved tree genera were generally similar (except for Betula) and assemblages from coniferous trees formed another distinct cluster.The subsequent indicator analysis proposed that there are different characteristic species for different cluster groups of host tree genera.In our study,log diameter has no positive influence on beetle species density.Conversely,comparisons of individual-based rarefaction curves suggested that beetle species richness was highest in the small diameter class both in coniferous and broad-leaved tree genera.With increased wood decay,proportion of habitat specialists (saproxylic beetles living on one tree genus)decreased,whereas proportion of habitat generalists (living on more than three tree genera)increased.The beetle species density was found to be higher in early stages,and decreased in later stages as well.A negative influence of altitude on saproxylic beetle species richness and abundance was detected.It was indicated that different tree genera and altitudes possibly display cross effects in modulating the altitudinal distribution and host preference of the beetles.

  12. 东灵山4种落叶阔叶次生林的物种组成与群落结构%Species composition and community structure of four deciduous broadleaved secondary forest in Dongling Mountain

    Institute of Scientific and Technical Information of China (English)

    李亮; 刘海丰; 白帆; 祝燕; 李广起; 李文超; 桑卫国

    2011-01-01

    植被的群落构成是决定森林演替方向的重要因素之一.辽东栎林(Quercus wutaishanica forest,QWF)、棘皮桦林(Betula dahurica forest,BDF)、胡桃楸林(Juglans mandshurica forest,JMF)与杂木林(mixed forest,MF)是东灵山地区4种典型的暖温带落叶阔叶次生林.为了更好地了解东灵山地区暖温带落叶阔叶次生林植被动态,我们对该4种林型的物种组成与群落结构进行了综合分析.参照巴拿马(Barro Colorado Island,BCI)50 ha热带雨林样地的技术规范,于2009年在北京东灵山地区以上4个林型中各建立了一块1 ha样地,对样地中所有胸径大于1 cm的木本个体进行了坐标定位和调查.结果表明,QWF样地有22种,属于20科20属;BDF样地共22种,属于16科18属;JMF样地30种,隶属于21科23属;MF样地19种,隶属于14科15属.从物种多度、平均胸径、胸高断面积和重要值等指标来看,各群落具有比较明显的优势种:4个样地所有树种的径级分布均旱倒"J"型,具有良好的更新层;共有树种的径级分布在不同样地有所不同,如辽东栎在QWF样地呈偏态分布,在BDF样地则为倒"J"型分布,而棘皮桦在QWF和BDF样地都呈正态分布,但是径级分布有所差异,表明径级结构与群落类型有密切关系.%The following are typical communities in the secondary deciduous broad-leaved forests in the Dongling Mountain area: Quercus wutaishanica forest (QWF), Betula dahurica forest (BDF), luglans mandshurica forest (JMF) and mixed forest (MF). Comprehensive research on species composition and community structure of these four forest types will contribute to a more thorough knowledge of the successional dynamics and ecological functions in warm temperate deciduous broad-leaved forests. Following the field protocol of the 50-ha plot on Barro Colorado Island in Panama, one l-ha plot was established in each of these forest types in Dongling Mountain in 2009. In these plots, all free-standing trees ≥1

  13. 关帝山森林土壤有机碳和氮素的空间变异特征%Spatial Variations of Soil Organic Carbon and Nitrogen of Forestland in Guandi Mountain

    Institute of Scientific and Technical Information of China (English)

    杨秀清; 韩有志

    2011-01-01

    Classical statistics and geo-statistics were used to analyze the spatial variations and distribution pattern of soil organic carbon( SOC), total nitrogen(TN) and C/N ratio of forestland in three ecological areas of Pangquangou National Nature Reserve in Guandi Mountain of Shanxi Province, China. The results showed that the SOC and TN increased firstly but fell off afterwards, the C/N decreased continually with the succession level from artificial forest to secondary broad-leaved forest composed of Betula albo-sinensis, Betula platyphylla and Populus davidiana in early phase succession, to secondary Picea, Populus, Betula mixed forest in later stage succession. The coefficient of variation of SOC, TN and C/N varied from 11.74% to 64.71% which showed medium variations. The Range of SOC and TN in artificial forest was larger but still smaller than that in secondary forest, this explained a lower variation degree and more homogeneous spatial distribution of SOC and TN in artificial forest than that in secondary forest.The structural variance ratio of SOC, TN and C/N in artificial forest was in the range of 0-64.8%, which meant a weak or medium spatial autocorrelation, while the structural variance ratio of SOC, TN and C/N in secondary forest was more than 75%, appearing high spatial autocorrelation, and structural variance ratio of the narrated above 3 index showed a increasing trend with progressive succession. Kriged maps showed that SOC, TN and C/N in artificial forest present a high fragmentized distributions but a regular patched distributions. Forest succession, disturbance and toporographic condition have important effects on spatial variation and its characteristics of SOC, TN and C/N of forestland.%在庞泉沟自然保护区选择3个生态功能区设置典型样地,运用经典统计学和地统计学方法研究了森林土壤有机碳、全氮及碳氮比的空间变异特征及分布格局.结果表明,随着生态系统由人工林→次生演

  14. 凉水保护区土壤产类漆酶-多铜氧化酶细菌群落结构%The community structure of laccase-like multicopper oxidase-producing bacteria in soil of Liangshui Nature Reserve

    Institute of Scientific and Technical Information of China (English)

    赵丹; 谷惠琦; 崔岱宗; 范晓旭; 张曦; 赵敏

    2012-01-01

    在凉水国家级自然保护区3种主要林型红松(Pinus koraiensis)、白桦(Betula platyphylla)及云杉(Picea dietrich)林采集林下土壤样品,以铜离子作为筛选剂处理后,结合平板分离法与基于16S rDNA V3区片段的变性梯度凝胶电泳(Denaturing Gradient Gel Electrophoresis,DGGE)技术,调查了土壤样品中产类漆酶-多铜氧化酶(laccase-like multicopper oxidase,LMCO)细菌的群落结构.这是研究产类漆酶-多铜氧化酶细菌在环境中存在的种、属及分布的新尝试.平板分离获得10株细菌均为芽孢杆菌属(Bacillus sp.),其中梭状芽孢杆菌(Bacillus fusiformis)未见相关报道.通过DGGE图谱分析可知,产类漆酶-多铜氧化酶细菌在研究地不同林型土壤中的群落结构无明显差异,在红松林土壤中多样性最为丰富.DGGE条带测序结果表明,取样地土壤中产类漆酶细菌主要为罗尔斯顿菌属(Ralstonia sp.)、肠杆菌属(Enterobacter sp.)、芽孢杆菌属和一些未培养细菌.%Laccases catalyze the oxidation of various aromatics, particularly phenolic and amine substrates, making them valuable in industrial applications. Laccases also play an important role in soil organic matter (SOM) turnover processes and the global carbon cycle due to their involvement in the synthesis and degradation of lignin as well as transformation of lignified substrates and humic substances. Laccases belong to the protein family of multicopper oxidases characterized by copper atoms in the active center. Laccases or laccase-like multicopper oxidases ( LMCO) have been extensively studied especially in fungi. Recently, increasing evidence points to a wide occurrence of LMCO in bacteria. As bacterial communities are known to decompose pollutants and municipal wastes involving large quantities of phenolic substances and organic matter, it can be deduced that bacterial LMCO might also participate in lignin degradation and SOM cycling. Copper atoms not only constitute

  15. 甘肃兴隆山主要森林类型土壤渗透性%Soil Infiltration Characteristics of Main Forest Types in Xinglong Mountain of Gansu

    Institute of Scientific and Technical Information of China (English)

    魏强; 凌雷; 张广忠; 柴春山; 闫沛斌; 陶继新

    2013-01-01

    0-60 cm soil layer of six main forests, including Picea wilosonii forest, Picea wilosonii and Betula platyphylla forest, Populus davidiana and Betula platyphylla forest, Catanester multiglorus and Rosa xanthina shrubs, Pinus tabulaeformis forest and Larix principis-rupprechtii forest in Xinglong Mountain of Gansu, was conducted to investigate the infiltration capability in 2010 and provide basis for the evaluation of water conservation function of forest and sustainable management of water conservation forests. The results showed that the infiltration eigenvalues of six forest types are as: initial infiltration rate>average infiltration rate>stable infiltration rate. The characteristics of soil infiltration differ significantly with deferent forest types. The comprehensive score for soil infiltration is in the range of -1.960 0-1.944 9, and the natural forest is obviously better than plantation. The soil infiltration capability of natural forest gradually increases with its development of positive succession. Correlation analysis showed that soil infiltration capability is greatly affected by soil physical and chemical properties. Soil infiltration has not only close relation with bulk density and porosity, but also with soil nutrient contents and pH. Combined with the correlation analysis, ten soil physical and chemical properties factors, which extremely significantly or significantly influenced soil infiltration, were selected to build four dominant factor equations of soil permeability by stepwise regression method with the correlation coefficient of higher than 0. 850 0 (P<0. 01 ). In four equations , the first introduced factor is the soil bulk density, and it is the most important one among many impact factors. The hydrolysable nitrogen, available phosphorus, total nitrogen, pH value and soil organic matter are the secondary factors. Horton infiltration model is the best one to describe the soil infiltration process of water conservation forests in

  16. On the Biomass of Four Major Tree Species in Vegetation Restoration Pattern Area of Beichuan Nature Reserve%北川自然保护区植被恢复模式区4种主要树种生物量研究

    Institute of Scientific and Technical Information of China (English)

    冯永林; 沈金亮; 张建设; 邓东周; 邵文; 王刚; 孙志鹏; 苏春英; 王刚

    2015-01-01

    In the experiment, by taking Quercus engleriana Seem., Betula albo-sinensis Burk., Abies faxoniana Rehd. and Fargesia rufa Yi, in the vegetation restoration pattern area of Beichuan Nature Reserve as the research objects, the study on the biomass models, the biomass distribution law of single plant and the growth rule of every organ of the four tree species was made. The results indicated that in the compositions of al of the species, the proportion of trunk biomass was the highest, while that of trunk biomass was the lowest, the proportions of branch and root biomasses varied depending on species; in the comparison of correlativity between the proportions of biomasses of al nutrition organs and biomass of single plant, the relations were general y significant, the tree trunks were positively related while the roots were negatively related; the proportion of trunk biomass of al species was significantly and negatively related to the proportions of leaf and branch biomasses, while the biomass of leaves was significantly and positively related to the biomass of branches.%以北川自然保护区植被恢复模式区巴东栎、红桦、岷江冷杉、青川箭竹为研究对象,对四种树种生物量模型、单株生物量分配规律以及各器官生长规律等进行研究。结果表明:在各树种生物量组成中,干生物量比例最大,叶最小,枝和根生物量比例因树种不同而有所差异;在各营养器官生物量比例与其单株生物量相关关系的比较中,整体上关系明显,树干为正相关,树根为负相关;树种干生物量比例与枝和叶生物量比例存在显著的负相关关系,而枝和叶生物量之间存在显著的正相关关系。

  17. CO{sub 2} enrichment and carbon partitioning to phenolics: do plant responses accord better with the protein competition or the growth differentiation balance models?

    Energy Technology Data Exchange (ETDEWEB)

    Mattson, W.J. [Forestry Sciences Lab., Rhinelander, WI (United States); Julkunen-Tiitto, R. [Univ. of Joensuu, Biology Dept., Joensuu (Finland); Herms, D.A. [Ohio State Univ., Dept. of Entmology, Wooster, OH (United States)

    2005-11-01

    Rising levels of atmospheric CO{sub 2} can alter plant growth and partitioning to secondary metabolites. The protein competition model (PCM) and the extended growth/differentiation balance model (GDB{sub e}) are similar but alternative models that address ontogenetic and environmental effects on whole-plant carbon partitioning to the phenylpropanoid biosynthetic pathway, making many divergentpredictins. To test the validity of the models, we compare plant responses to one key prediction: if CO{sub 2} enrichment simultaneously stimulates both photosynthesis and growth, then PCM predicts that partitioning to phenolic compounds will decline, whereas GDB{sub e} generally predicts the opposite. Elevated CO{sub 2} (at 548 ppm) increased the biomass growth (ca 23%) as well as the net photosynthesis (ca 13%) of 1-year-old potted paper birch, Betula papyrifera Marsch., in a free air carbon dioxide enrichment study (FACE) in northern Wisconsin. Concomitantly, elevated CO{sub 2} increased carbon partitioning to all measured classes of phenolics (Folin-Denis phenolics, HPLC low molecular weight phenolics (i.e. cinnamic acid derivatives, flavonol flycosides, and flavon-3-ols), condensed tannins, and acid-detergent lignin) in leaves. In stem tissues, tannins and lignin increased, but F-D phenolics did not. In root tissues, F-D phenolics, and tannins increased, but lignin did not. The data suggest that CO{sub 2} enrichment stimulated pathway-wide increase in carbon partitioning to phenylpropanoids. High CO{sub 2} plants had 11.8% more F-D phenolics, 19.3% more tannin, and 10% more lignin than ambient plants after adjusting for plant mass via analysis of covariance. In general, the results unequivocally support the predictions of the GDB{sub e} model. By way of contrast, results from many parallel studies on FACE trembling aspen, Populus tremuloides Michx., suggest that although 2 enrichment has consistently stimulated both photosynthesis and growth, it apparently did not

  18. Experimental study of terrestrial plant litter interaction with aqueous solutions

    Science.gov (United States)

    Fraysse, F.; Pokrovsky, O. S.; Meunier, J.-D.

    2010-01-01

    Quantification of silicon and calcium recycling by plants is hampered by the lack of physico-chemical data on reactivity of plant litter in soil environments. We applied a laboratory experimental approach for determining the silica and calcium release rates from litter of typical temperate and boreal plants: pine ( Pinus laricio), birch ( Betula pubescens), larch ( Larix gmelinii), elm ( Ulmus laevis Pall.), tree fern ( Dicksonia squarrosa), and horsetail (Equisetum arvense) in 0.01 M NaCl solutions, pH of 2-10 and temperature equals to 5, 25 and 40 °C. Open system, mixed-flow reactors equipped with dialysis compartment and batch reactors were used. Comparative measurements were performed on intact larch needles and samples grounded during different time, sterilized or not and with addition or not of sodium azide in order to account for the effect of surface to mass ratio and possible microbiological activity on the litter dissolution rates. Litter degradation results suggest that the silica release rate is independent on dissolved organic carbon release (cell breakdown) which implies the presence of phytoliths in a pure "inorganic" pool not complexed with organic matter. Calcium and DOC are released at the very first stage of litter dissolution while Si concentration increases gradually suggesting the presence of Ca and Si in two different pools. The dry-weight normalized dissolution rate at circum-neutral pH range (approx. 1-10 μmol/g DW/day) is 2 orders of magnitude higher than the rates of Si release from common soil minerals (kaolinite, smectite, illite). Minimal Ca release rates evaluated from batch and mixed-flow reactors are comparable with those of most reactive soil minerals such as calcite and apatite, and several orders of magnitude higher than the dissolution rates of major rock-forming silicates (feldspars, pyroxenes). The activation energy for Si liberation from plant litter is approx. 50 kJ/mol which is comparable with that of surface

  19. Variability and ecology of Siberian larch species

    Energy Technology Data Exchange (ETDEWEB)

    Abaimov, A.P.; Milyutin, L.I. [Russian Academy of Sciences, Krasnoyarsk (Russian Federation). Sukachev Inst. of Forest, Siberian Branch; Lesinski, J.A.; Martinsson, Owe [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Silviculture

    1998-12-31

    There are at least four larch taxons distinguished in Siberia that occupy almost 37 percent of the the Russian forests. The natural distribution of the taxons is clinal from the west to the east with L. sibirica Ledeb. in the west followed by L. x czekanowskii Szafer, L. gmelinii Rupr. and L. cajanderi Mayr. L. sibirica and L. x czekanowskii are phytocenosis builders only at the northern timberline and in the South-Siberian mountains whereas L. gmelinii and L. cajanderi are the main species over the vast territory within and beyond the permafrost zone of East Siberia. Due to large variety of growing conditions, the main features of the larch forests in terms of age structure and growth rates are also enormously variable. Thanks to specific life strategies with respect to seed dispersion patterns and very high adaptability to fires that often affect Siberian forests, these larch species regenerate very well being only seldom temporary replaced by Betula sp. forming secondary forest associations. Larch forests of different categories (protective and commercial) are exploited and regenerated in the same way as it is applied for Scots pine in Siberia. There is a growing interest in Siberian larch species among researchers and practitioners from abroad, mainly due to their fast growth and excellent wood properties. Some attempts of introducing Siberian larch species as commercial plantations have already been initiated in western countries. However, the knowledge of botanical, ecological and silvicultural features of Siberian larch species is rather poor outside of Russia. Because of its economic importance for Russian forestry the Siberian larch species have been comprehensively studied for many years and many papers as well as a number of monographs have been published, most of them in Russian. The large Russian expertise concerning regionalisation of seed sources, seed crop and quality, seed orchards, seedling production in nurseries and silvicultural practices in

  20. Impact of late glacial climate variations on stratification and trophic state of the meromictic lake Längsee (Austria: validation of a conceptual model by multi proxy studies

    Directory of Open Access Journals (Sweden)

    Jens MÜLLER

    2002-02-01

    Full Text Available Selected pigments, diatoms and diatom-inferred phosphorus (Di-TP concentrations of a late glacial sediment core section of the meromictic Längsee, Austria, were compared with tephra- and varve-dated pollen stratigraphic and geochemical results. A conceptual model was adopted for Längsee and evaluated using multi proxy data. During the unforested late Pleniglacial, a holomictic lake stage with low primary productivity prevailed. Subsequent to the Lateglacial Betula expansion, at about 14,300 cal. y BP, okenone and isorenieratene, pigments from purple and green sulphur bacteria, indicate the onset of anoxic conditions in the hypolimnion. The formation of laminae coincides with this anoxic, meromictic period with high, though fluctuating, amounts of okenone that persisted throughout the Lateglacial interstadial. The occurrence of unlaminated sediment sections of allochthonous origin, and concurrent low concentrations of okenone, were related to cool and wet climate fluctuations during this period, probably coupled with a complete mixing of the water column. Two of these oscillations of the Lateglacial interstadial have been correlated tentatively with the Aegelsee and Gerzensee oscillations in the Alps. The latter climate fluctuation divides a period of enhanced anoxia and primary productivity, correlated with the Alleröd chronozone. Continental climate conditions were assumed to be the main driving forces for meromictic stability during Alleröd times. In addition, calcite dissolution due to severe hypolimnetic anoxia, appear to have supported meromictic stability. Increased pigment concentrations, which are in contrast to low diatom-inferred total phosphorus (Di- TP, indicate the formation of a productive metalimnion during this period, probably due to a clear-water phase (low catchment erosion, increased temperatures, and a steep gradient between the phosphorus enriched hypolimnion and the oligotrophic epilimnion. Meltwater impacts from an