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Sample records for acer freemanii

  1. Accelerator Center for Energy Research (ACER)

    Federal Laboratory Consortium — The Accelerator Center for Energy Research (ACER) exploits radiation chemistry techniques to study chemical reactions (and other phenomena) by subjecting samples to...

  2. Sex Change Towards Female in Dying Acer rufinerve Trees

    Nanami, Satoshi; KAWAGUCHI, HIDEYUKI; Yamakura, Takuo

    2004-01-01

    • Background and Aims Sex changes within the genus Acer (Aceraceae) may occur because of associations of sex expression and plant health. In this study, a natural population of Acer rufinerve was monitored to clarify the sex change patterns, the relationship between sex expression and plant health, and the causal environmental conditions that precede sex changes.

  3. Motllo d'acer per safata Undertray

    Sánchez Benages , Esteban

    2006-01-01

    El projecte pretén dissenyar un motllo per produir una peça de PP (polipropilè) en sèrie. S’ha partit d’un plànol de fabricació de la peça de plàstic. Aquesta peça és una safata situada sota els seients davanters d’un vehicle. El motllo que s’ha dissenyat és d’acer amb corredisses. És d’interès el sistema de refrigeració emprat basat en circuits d’aigua. S’ha creat un model de la peça en 3 dimensions per tal de poder simular el procés d’injecció. Mitjançant la simulació del ...

  4. ACER Spelling Test: Years 3-6. Handbook.

    Australian Council for Educational Research, Hawthorn.

    The Australian Council for Educational Research (ACER) Spelling Test is designed to measure levels of achievement in spelling and comprises Test Cards, Answer Sheets, Class Analysis Charts and Handbook. The test itself is divided into four parts, one part for each of years 3 through 6 with each part consisting of 50 words. Directions for…

  5. ACER: demystifying the European energy supervisor from a consumer perspective

    S.A.C.M. Lavrijssen; I. Bordei

    2012-01-01

    The European energy regulatory triangle, consisting of National Regulatory Authorities (NRAs), the European Commission and the newly established Agency for the Cooperation of Energy Regulators (ACER), has an important role in enhancing cross border trade and wholesale market competition and ultimate

  6. Monitoring the Health of Sugar Maple, "Acer Saccharum"

    Carlson, Martha

    2013-01-01

    The sugar maple, "Acer saccharum," is projected to decline and die in 88 to 100 percent of its current range in the United States. An iconic symbol of the northeastern temperate forest and a dominant species in this forest, the sugar maple is identified as the most sensitive tree in its ecosystem to rising temperatures and a warming…

  7. Phenolic glycosides from sugar maple (Acer saccharum) bark.

    Yuan, Tao; Wan, Chunpeng; González-Sarrías, Antonio; Kandhi, Vamsikrishna; Cech, Nadja B; Seeram, Navindra P

    2011-11-28

    Four new phenolic glycosides, saccharumosides A-D (1-4), along with eight known phenolic glycosides, were isolated from the bark of sugar maple (Acer saccharum). The structures of 1-4 were elucidated on the basis of spectroscopic data analysis. All compounds isolated were evaluated for cytotoxicity effects against human colon tumorigenic (HCT-116 and Caco-2) and nontumorigenic (CCD-18Co) cell lines. PMID:22032697

  8. Molecular characterization and differential expression of two duplicated odorant receptor genes, AcerOr1 and AcerOr3, in Apis cerana cerana

    Huiting Zhao; Pengfei Gao; Haiyan Du; Weihua Ma; Songhao Tian; Yusuo Jiang

    2014-04-01

    Insects use olfaction to recognize a wide range of volatile cues, to locate food sources, mates, hosts and oviposition sites. These chemical volatiles are perceived by odorant receptors (ORs) expressed on the dendritic membrane of olfactory neurons, most of which are housed within the chemosensilla of antennae. Most insect ORs are tandemly arrayed on chromosomes and some of them are formed by gene duplication. Here, we identified a pair of duplicated Or genes, AcerOr1 and AcerOr3, from the antennae of the Asian honeybee, Apis cerana cerana, and reported their molecular characterization and temporal expression profiles. The results showed that these two genes shared high similarity both in sequence and the gene structure. Quantitative real-time PCR analysis of temporal expression pattern indicated that in drones the expression pattern of these two genes were very similar. The transcripts expressed weakly in larvae and pupae, then increased gradually in adults. In workers, the expression level of AcerOr1 changed more drastically and expressed higher than that of AcerOr3. However, both reached their highest expression level in one-day-old adults. In addition, the expression profiles between different sexes revealed that AcerOr3 appear to be expressed biased in male antennae. These results suggest that AcerOr1 may perceive odours of floral scents, while AcerOr3 may detect odours critical to male behaviour, such as the queen substance cues.

  9. Molecular characterization and differential expression of two duplicated dorant receptor genes, AcerOr1 and AcerOr3, in Apis cerana cerana.

    Zhao, Huiting; Gao, Pengfei; Du, Haiyan; Ma, Weihua; Tian, Songhao; Jiang, Yusuo

    2014-04-01

    Insects use olfaction to recognize a wide range of volatile cues, to locate food sources, mates, hosts and oviposition sites. These chemical volatiles are perceived by odorant receptors (ORs) expressed on the dendritic membrane of olfactory neurons, most of which are housed within the chemosensilla of antennae. Most insect ORs are tandemly arrayed on chromosomes and some of them are formed by gene duplication. Here, we identified a pair of duplicated Or genes, AcerOr1 and AcerOr3, from the antennae of the Asian honeybee, Apis cerana cerana, and reported their molecular characterization and temporal expression profiles. The results showed that these two genes shared high similarity both in sequence and the gene structure. Quantitative real-time PCR analysis of temporal expression pattern indicated that in drones the expression pattern of these two genes were very similar. The transcripts expressed weakly in larvae and pupae, then increased gradually in adults. In workers, the expression level of AcerOr1 changed more drastically and expressed higher than that of AcerOr3. However, both reached their highest expression level in one-day-old adults. In addition, the expression profiles between different sexes revealed that AcerOr3 appear to be expressed biased in male antennae. These results suggest that AcerOr1 may perceive odours of floral scents, while AcerOr3 may detect odours critical to male behaviour, such as the queen substance cues. PMID:24840823

  10. Volatiles from a Rare Acer spp. Honey Sample from Croatia

    Igor Jerković

    2010-06-01

    Full Text Available A rare sample of maple (Acer spp. honey from Croatia was analysed. Ultrasonic solvent extraction (USE using: 1 pentane, 2 diethyl ether, 3 a mixture of pentane and diethyl ether (1:2 v/v and 4 dichloromethane as solvents was applied. All the extracts were analysed by GC and GC/MS. The most representative extracts were 3 and 4. Syringaldehyde was the most striking compound, being dominant in the extracts 2, 3 and 4 with percentages 34.5%, 33.1% and 35.9%, respectively. In comparison to USE results of other single Croatian tree honey samples (Robinia pseudoacacia L. nectar honey, Salix spp. nectar and honeydew honeys, Quercus frainetto Ten. honeydew as well as Abies alba Mill. and Picea abies L. honeydew and literature data the presence of syringaldehyde, previously identified in maple sap and syrup, can be pointed out as a distinct characteristic of the Acer spp. honey sample. Headspace solid-phase microextraction (HS-SPME combined with GC and GC/MS identified benzaldehyde (16.5%, trans-linalool oxide (20.5% and 2-phenylethanol (14.9% as the major compounds that are common in different honey headspace compositions.

  11. The perspectives of involvement of Acer platanoides L. in medical practice

    Oksana Cherpak

    2013-04-01

    Full Text Available The content of tannins, flavonoids, β-carotene, chlorophyll a, anthocyanins, coumarins and alkaloids in leaves of Acer platanoides was ascertained on the basis of phytochemical study.

  12. THE ANALYSIS OF ACER COMPUTER’S INTERNATIONALIZATION PROCESS FROM THE RESOURCE-BASED VIEW

    HUANG, YING TZU

    2009-01-01

    This paper focuses on the analysis of Acer Corporation’s internationalisation process from the Resource-Based view, RBV. Qualitative research method will be adopted in terms of the data collection throughout the entire research. It aims to examine the business strategies that Acer has adopted in terms of resources gathering and development. In addition, its internationalization pattern will also be compared and analyzed with the established theories such as the Uppsala Model, to see if it ...

  13. RAPD analysis on genomic DNA of male and female plants of Acer negundo L.

    1999-01-01

    Genomic DNAs were isolated from both male and female plants of Acer negundo L., by modified CTAB method of Doyle and Doyle for plant genomic DNA isolation and consequently tested with RAPD technique.Some sex-related specific oxyribonucleic acid bands were amplified bY a group of decamer oligonucleotide random primers. This indicated that some genetic marks related to sexes of the species were found, which laid a foundation for sapling sex identification of Acer negundo L.

  14. Simulated herbivory advances autumn phenology in Acer rubrum

    Forkner, Rebecca E.

    2014-05-01

    To determine the degree to which herbivory contributes to phenotypic variation in autumn phenology for deciduous trees, red maple ( Acer rubrum) branches were subjected to low and high levels of simulated herbivory and surveyed at the end of the season to assess abscission and degree of autumn coloration. Overall, branches with simulated herbivory abscised ˜7 % more leaves at each autumn survey date than did control branches within trees. While branches subjected to high levels of damage showed advanced phenology, abscission rates did not differ from those of undamaged branches within trees because heavy damage induced earlier leaf loss on adjacent branch nodes in this treatment. Damaged branches had greater proportions of leaf area colored than undamaged branches within trees, having twice the amount of leaf area colored at the onset of autumn and having ˜16 % greater leaf area colored in late October when nearly all leaves were colored. When senescence was scored as the percent of all leaves abscised and/or colored, branches in both treatments reached peak senescence earlier than did control branches within trees: dates of 50 % senescence occurred 2.5 days earlier for low herbivory branches and 9.7 days earlier for branches with high levels of simulated damage. These advanced rates are of the same time length as reported delays in autumn senescence and advances in spring onset due to climate warming. Thus, results suggest that should insect damage increase as a consequence of climate change, it may offset a lengthening of leaf life spans in some tree species.

  15. Altered Acer Rubrum Fecundity Induced By Chemical Climate Change

    Deforest, J. L.; Peters, A.

    2014-12-01

    Red maple (Acer rubrum L.) is becoming the most dominating tree in North American eastern deciduous forests. Concurrently, human activities have altered the chemical climate of terrestrial ecosystems via acidic deposition, which increases the available of nitrogen (N), while decreasing phosphorus (P) availability. Once a minor forest component prior to European settlement, the abundance of red maple may be a symptom of the modern age. The current paradigm explaining red maple's rise to prominence concerns fire suppression that excludes competitors. However, this still does not explain why red maple is unique compared to other functionally similar trees. The objective of this study was to investigate the interactive influence of acid rain mitigation on the fecundity of red maple. Objectives were achieved by measuring flowering, seed production, germination, and growth from red maple on plots that have been experimentally manipulated to increase soil pH, P, or both in three unglaciated eastern deciduous hardwood forests. At least 50% of the red maple population is seed bearing in our control soils, however the median percent of seed-bearing trees declined to zero when mitigating soils from acidic deposition. This can be explained by the curious fact that red maple is polygamodioecious, or has labile sex-expression, in which an individual tree can change its sex-expression in response to the environment. Furthermore, seed-bearing trees in the mitigated plots grew less, produced less seeds, and germinated at lower rates than their counterparts in control soils. Our results provide evidence that chemical climate change could be the primary contributing factor accelerating the dominance of red maple in eastern North American forests. Our observations can provide a boarder conceptual framework for understanding how nutrient limitations can be applied beyond plant productivity towards explaining distribution changes in vegetation.

  16. Effect of Alnus subcordata, Acer insigne and Sequoia sempervirens plantations on plant diversity in Hyrcanian forest of Iran

    FATEMEH GHEIBI; MOSLEM AKBARINIA; YAHYA KOOCH

    2015-01-01

    Gheibi F, Akbarinia M, Kooch Y. 2015. Effect of Alnus subcordata, Acer insigne and Sequoia sempervirens plantations on plant diversity in Hyrcanian forest of Iran. Biodiversitas 16: 10-15. Forest plantation is a common action in order to restore the degraded forests in Hyrcanian forests of Iran. This study compares the plant biodiversity in four 25-year-old stands of plantation, adjacent understory of alder (Alnus subcordata C. A. Mey.), maple (Acer insigne Boiss.), sequoia or red wood (Sequo...

  17. The Addenbrooke's Cognitive Examination Revised (ACE-R) and its sub-scores: normative values in an Italian population sample.

    Siciliano, Mattia; Raimo, Simona; Tufano, Dario; Basile, Giuseppe; Grossi, Dario; Santangelo, Franco; Trojano, Luigi; Santangelo, Gabriella

    2016-03-01

    The Addenbrooke's Cognitive Examination Revised (ACE-R) is a rapid screening battery, including five sub-scales to explore different cognitive domains: attention/orientation, memory, fluency, language and visuospatial. ACE-R is considered useful in discriminating cognitively normal subjects from patients with mild dementia. The aim of present study was to provide normative values for ACE-R total score and sub-scale scores in a large sample of Italian healthy subjects. Five hundred twenty-six Italian healthy subjects (282 women and 246 men) of different ages (age range 20-93 years) and educational level (from primary school to university) underwent ACE-R and Montreal Cognitive Assessment (MoCA). Multiple linear regression analysis revealed that age and education significantly influenced performance on ACE-R total score and sub-scale scores. A significant effect of gender was found only in sub-scale attention/orientation. From the derived linear equation, a correction grid for raw scores was built. Inferential cut-offs score were estimated using a non-parametric technique and equivalent scores (ES) were computed. Correlation analysis showed a good significant correlation between ACE-R adjusted scores with MoCA adjusted scores (r = 0.612, p population useful for both clinical and research purposes. PMID:26563847

  18. Early Autumn Senescence in Red Maple (Acer rubrum L.) Is Associated with High Leaf Anthocyanin Content

    Rachel Anderson; Peter Ryser

    2015-01-01

    Several theories exist about the role of anthocyanins in senescing leaves. To elucidate factors contributing to variation in autumn leaf anthocyanin contents among individual trees, we analysed anthocyanins and other leaf traits in 27 individuals of red maple (Acer rubrum L.) over two growing seasons in the context of timing of leaf senescence. Red maple usually turns bright red in the autumn, but there is considerable variation among the trees. Leaf autumn anthocyanin contents were consiste...

  19. Morphology and cytology of three flower phenotypes in a duodichogamous tree species, Acer mono

    Lingzhi Zhang; Hui Shang; Yibo Luo; Xin Cheng; Weining Bai

    2011-01-01

    Duodichogamy, where individual plants produce two batches of male flowers that are temporally separated by a batch of female flowers, is the rarest temporal sexual system in flowering plants. Duodichogamy is present in some species of Acer, whose flowers of the first (male I) and second male phases (male II) differ morphologically. To explore the influence of floral development on flower morphology and phenology, we used paraffin methods and light microscopy to compare morphological and cytol...

  20. Functional analysis of embolism induced by air injection in Acer rubrum and Salix nigra

    Peter Jegsen Melcher; Maciej Andrzej Zwieniecki

    2013-01-01

    The goal of this study was to assess the effect of induced embolism with air injection treatments on the function of xylem in Acer rubrum L. and Salix nigra Marsh. Measurements made on mature trees of A. rubrum showed that pneumatic pressurization treatments that created a pressure gradient of 5.5 MPa across pit membranes (DPpit) had no effect on stomatal conductance or on branch-level sap flow. The same air injection treatments made on three year old potted A. rubrum plants also had no eff...

  1. Enfermedad pulmonar por amianto en trabajadores de acería

    2013-01-01

    Las enfermedades relacionadas al amianto se producen por la inhalación de fibras de asbestos en su variedad crisotilo o amianto blanco. A pesar de que en la Argentina la prohibición data del año 2003, existen numerosas industrias donde se sigue trabajando con este mineral, entre ellas las metalúrgicas y acerías. Actualmente se conoce la alta patogenicidad de este material, por lo que en muchos países existen programas de seguimiento de los trabajadores expuestos. Se describen las característi...

  2. The chemical identity of intervessel pit membranes in Acer challenges hydrogel control of xylem hydraulic conductivity

    Klepsch, Matthias M.; Schmitt, Marco; Paul Knox, J.; Jansen, Steven

    2016-01-01

    Ion-mediated enhancement of the hydraulic conductivity of xylem tissue (i.e. the ionic effect) has been reported for various angiosperm species. One explanation of the ionic effect is that it is caused by the swelling and shrinking of intervessel pit membranes due to the presence of pectins and/or other cell-wall matrix polymers such as heteroxylans or arabinogalactan–proteins (AGPs) that may contain acidic sugars. Here, we examined the ionic effect for six Acer species and their pit membrane chemistry using immunocytochemistry, including antibodies against glycoproteins. Moreover, anatomical features related to the bordered pit morphology and vessel dimensions were investigated using light and electron microscopy. The ionic effect varied from 18 % (± 9) to 32 % (± 13). Epitopes of homogalacturonan (LM18) and xylan (LM11) were not detected in intervessel pit membranes. Negative results were also obtained for glycoproteins (extensin: LM1, JIM20; AGP glycan: LM2), although AGP (JIM13)-related epitopes were detected in parenchyma cells. The mean vessel length was significantly correlated with the magnitude of the ionic effect, unlike other pit or vessel-related characteristics. Our results suggest that intervessel pit membranes of Acer are unlikely to contain pectic or other acidic polysaccharides. Therefore, alternative explanations should be tested to clarify the ionic effect. PMID:27354661

  3. The chemical identity of intervessel pit membranes in Acer challenges hydrogel control of xylem hydraulic conductivity.

    Klepsch, Matthias M; Schmitt, Marco; Paul Knox, J; Jansen, Steven

    2016-01-01

    Ion-mediated enhancement of the hydraulic conductivity of xylem tissue (i.e. the ionic effect) has been reported for various angiosperm species. One explanation of the ionic effect is that it is caused by the swelling and shrinking of intervessel pit membranes due to the presence of pectins and/or other cell-wall matrix polymers such as heteroxylans or arabinogalactan-proteins (AGPs) that may contain acidic sugars. Here, we examined the ionic effect for six Acer species and their pit membrane chemistry using immunocytochemistry, including antibodies against glycoproteins. Moreover, anatomical features related to the bordered pit morphology and vessel dimensions were investigated using light and electron microscopy. The ionic effect varied from 18 % (± 9) to 32 % (± 13). Epitopes of homogalacturonan (LM18) and xylan (LM11) were not detected in intervessel pit membranes. Negative results were also obtained for glycoproteins (extensin: LM1, JIM20; AGP glycan: LM2), although AGP (JIM13)-related epitopes were detected in parenchyma cells. The mean vessel length was significantly correlated with the magnitude of the ionic effect, unlike other pit or vessel-related characteristics. Our results suggest that intervessel pit membranes of Acer are unlikely to contain pectic or other acidic polysaccharides. Therefore, alternative explanations should be tested to clarify the ionic effect. PMID:27354661

  4. Energy regulation at EU level. The role of the European Commission and ACER in the context of REMIT; Energieregulierung auf Unionsebene. Die Rolle der Europaeischen Kommission und der ACER nach der REMIT-VO

    Konar, Selma [Sozietaet Becker Buettner Held, Muenchen (Germany). Energie- und Infrastrukturrecht

    2015-03-15

    The regulatory act of promulgating REMIT, the Regulation on Wholesale Market Integrity and Transparency, has highlighted the commanding position of both the European Commission and ACER, the Agency for the Cooperation of Energy Regulators, in the regulation of energy affairs in the European Union. Furthermore it has led to major changes in how surveillance is organized at the national level. The first part of this publication is dedicated to the organization of market surveillance following the promulgation of REMIT. It depicts the tasks of the European Commission and ACER in this context. The Regulation has accorded the authorities a central role in managing the European Union's responsibilities with regard to energy wholesale trade. The act of delegating such far-reaching competence to the authorities deserves careful review however. The article shows how, given ACER's lack of practical experience in market surveillance, as well as its lack of human resources, the task of surveilling the European energy wholesale market confronts the agency with a significant challenge. How successfully the EU energy agency will master this challenge will depend on a number of different factors. Stringent requirements will be needed for the data registration offices in order to ensure optimal data processing. National authorities and supervisory bodies should be made to participate in the data monitoring process. ACER's efficiency in surveilling the market will furthermore depend decisively on its IT infrastructure.

  5. Peculiarities of accumulation of nonstructural carbohydrates in shoots of various species of acer genus in conditions of coke process

    V. S. Bilchuk

    2005-11-01

    Full Text Available The research results on influence of the by-product-coking industry emission on starch and saccharose accumulation in sprouts of the Acer L. species are presented. The toxic ingredients of the coke production wastes inhibit the process of starch hydrolysis that provokes considerable decrease of the sugars content and negative influence on the plants’ winter hardiness are established.

  6. Energy regulation at EU level. The role of the European Commission and ACER in the context of REMIT

    The regulatory act of promulgating REMIT, the Regulation on Wholesale Market Integrity and Transparency, has highlighted the commanding position of both the European Commission and ACER, the Agency for the Cooperation of Energy Regulators, in the regulation of energy affairs in the European Union. Furthermore it has led to major changes in how surveillance is organized at the national level. The first part of this publication is dedicated to the organization of market surveillance following the promulgation of REMIT. It depicts the tasks of the European Commission and ACER in this context. The Regulation has accorded the authorities a central role in managing the European Union's responsibilities with regard to energy wholesale trade. The act of delegating such far-reaching competence to the authorities deserves careful review however. The article shows how, given ACER's lack of practical experience in market surveillance, as well as its lack of human resources, the task of surveilling the European energy wholesale market confronts the agency with a significant challenge. How successfully the EU energy agency will master this challenge will depend on a number of different factors. Stringent requirements will be needed for the data registration offices in order to ensure optimal data processing. National authorities and supervisory bodies should be made to participate in the data monitoring process. ACER's efficiency in surveilling the market will furthermore depend decisively on its IT infrastructure.

  7. A Nuclear Ribosomal DNA Phylogeny of Acer Inferred with Maximum Likelihood, Splits Graphs, and Motif Analysis of 606 Sequences

    Guido W. Grimm

    2006-01-01

    Full Text Available The multi-copy internal transcribed spacer (ITS region of nuclear ribosomal DNA is widely used to infer phylogenetic relationships among closely related taxa. Here we use maximum likelihood (ML and splits graph analyses to extract phylogenetic information from ~ 600 mostly cloned ITS sequences, representing 81 species and subspecies of Acer, and both species of its sister Dipteronia. Additional analyses compared sequence motifs in Acer and several hundred Anacardiaceae, Burseraceae, Meliaceae, Rutaceae, and Sapindaceae ITS sequences in GenBank. We also assessed the effects of using smaller data sets of consensus sequences with ambiguity coding (accounting for within-species variation instead of the full (partly redundant original sequences. Neighbor-nets and bipartition networks were used to visualize conflict among character state patterns. Species clusters observed in the trees and networks largely agree with morphology-based classifications; of de Jong’s (1994 16 sections, nine are supported in neighbor-net and bipartition networks, and ten by sequence motifs and the ML tree; of his 19 series, 14 are supported in networks, motifs, and the ML tree. Most nodes had higher bootstrap support with matrices of 105 or 40 consensus sequences than with the original matrix. Within-taxon ITS divergence did not differ between diploid and polyploid Acer, and there was little evidence of differentiated parental ITS haplotypes, suggesting that concerted evolution in Acer acts rapidly.

  8. Morphometric characteristics of the leaves of Greek maple (Acer heldreichii Orph in central Serbia

    Perović Marko

    2007-01-01

    Full Text Available The taxonomic characteristics of Greek maple (Acer heldreichii Orph were studied based on the analysis of leaf characteristics, by comparative-morphological method. The study was performed at three localities in central Serbia: Goč, Jastrebac and Rudnik. 30 normally developed trees were selected per each locality, and 30 leaves were selected from each tree for the analysis. The study includes 8 measured and 15 derived characteristics of leaves. The study results were statistically processed by correlation analysis, analysis of variance and cluster-analysis. It is concluded that there are two varieties, var. heldreichii and var. macropterum. Four forms are set aside in the variety macropterum: f. typicum f. dissectum, f. Equiloba and f. rotundiloba. The populations are relatively homogeneous, and both varieties occur at all three localities in significant numbers.

  9. Enfermedad pulmonar por amianto en trabajadores de acería

    Rita Zurbriggen

    2013-06-01

    Full Text Available Las enfermedades relacionadas al amianto se producen por la inhalación de fibras de asbestos en su variedad crisotilo o amianto blanco. A pesar de que en la Argentina la prohibición data del año 2003, existen numerosas industrias donde se sigue trabajando con este mineral, entre ellas las metalúrgicas y acerías. Actualmente se conoce la alta patogenicidad de este material, por lo que en muchos países existen programas de seguimiento de los trabajadores expuestos. Se describen las características generales y manifestaciones clínicas pulmonares de 27 pacientes que trabajaron en una gran acería de América del Sur. El diagnóstico de amiantopatías se realizó mediante historia clínica laboral, antecedente de exposición al amianto, estudios complementarios de función pulmonar e imágenes del tórax. Se analizaron la fuente de exposición (laboral, doméstica y ambiental, tiempo de exposición y período de latencia en los pacientes de los cuales se detectó enfermedad relacionada. Los antecedentes de tabaquismo fueron tenidos en cuenta para el análisis. En 22 pacientes se presentaron patologías benignas (81.4%, 16 de ellos tenían lesiones exclusivamente pleurales y otros 6 asbestosis. Las patologías malignas se presentaron en 5 pacientes (18.5%, en 4 fueron mesoteliomas y en uno carcinoma pulmonar. El problema de la exposición al amianto tiene vigencia actual. De ahí la necesidad de un programa de vigilancia en trabajadores expuestos al amianto actualmente o en el pasado, para detectar, notificar, registrar e investigar las características de estas patologías.

  10. Pengaruh Harga, Kualitas, dan Citra Merek terhadap Keputusan Pembelian notebook Acer pada Mahasiswa Fakultas Ekonomi Universitas Sumatera Utara

    Manurung, Gustyna

    2012-01-01

    The research is titled” The effect of Price, Quality, and Brand Image Towards purchasing decision to student of North Sumatera University from Economy Faculty. The objective of this research is knowing the effect of Price, Quality, and Brand Image notebook Acer Towards purchasing decision to student of North Sumatera University from Economy Faculty. The kind of this research is explanatory research. Analysis method to test the hypotezis by using multiple linier regression, simultaneous t...

  11. Influence of bigleaf maple (Acer Macrophyllum Pursh) on soil properties in a conifer forest of southwest British Columbia

    Chandler, Julia

    2006-01-01

    The overall objective of this research was to detect the influence of bigleaf maple (Acer macrophyllum Pursh) on soils in a conifer forest of southwest British Columbia. Forest floor properties were measured beneath bigleaf maple along six transects and on two 36 m x 36 m plots. Wavelet analysis, kriging, spatial autocorrelation analysis, local indicators of spatial association, and parametric statistics were used to explore and confirm bigleaf maple patterns of influence on surrounding soils...

  12. Phenotypic variability of plant leaves of Acer genus, introduced into steppe zone of Ukraine

    I. O. Zaitseva

    2014-10-01

    Full Text Available This paper deals with studying of the patterns of ecological adaptation of wood species of Acer L. genus during their introduction into steppe zone of Ukraine. Hydrothermal conditions of the growing season in steppe zone of Ukraine are particularly unfavorable for tree and shrubbery plantings, comprising both native and introduced species. In the course of plants’ introduction, adaptive changes occur; such changes represent the spectrum of phenotypic implementation of the definite genotype under the influence of new environmental conditions. Stress environment of the region of introduction leads to occurrence of a great variety of phenotypic forms, as the different variants of genotype implementation. Studying of phenotypic variability gives an opportunity to determine the capacity to adaptation of introduced species and ways of adaptive reactions in new conditions of living. Therefore, objective of the work consists in studying of the processes of differentiation of morphological characters in species of Acer genus introduced in the regions of steppe zone with varying intensity of hydrothermal factors. Studies were carried out in the central and south-eastern steppe regions, as well as in the south of steppe zone in the coastal and continental areas. Subjects of research were 9 species of maples, differing by their botanic and geographic origin and by the degree of drought resistance in the steppe zone of Ukraine. Patterns of variability of morphostructural characters of leaves were determined by the indicator of specific weight of leaves which was calculated as a ratio of weight of dry laminas to their area (mg/cm2. Following the results of study, it was found that adaptation of maples to xerothermic factors of the environment is connected with changing of the ratio of groups of character variation and their contribution into total sample. Direct relationship is established between the probability density of expression (phenotypic

  13. Early Autumn Senescence in Red Maple (Acer rubrum L. Is Associated with High Leaf Anthocyanin Content

    Rachel Anderson

    2015-08-01

    Full Text Available Several theories exist about the role of anthocyanins in senescing leaves. To elucidate factors contributing to variation in autumn leaf anthocyanin contents among individual trees, we analysed anthocyanins and other leaf traits in 27 individuals of red maple (Acer rubrum L. over two growing seasons in the context of timing of leaf senescence. Red maple usually turns bright red in the autumn, but there is considerable variation among the trees. Leaf autumn anthocyanin contents were consistent between the two years of investigation. Autumn anthocyanin content strongly correlated with degree of chlorophyll degradation mid to late September, early senescing leaves having the highest concentrations of anthocyanins. It also correlated positively with leaf summer chlorophyll content and dry matter content, and negatively with specific leaf area. Time of leaf senescence and anthocyanin contents correlated with soil pH and with canopy openness. We conclude that the importance of anthocyanins in protection of leaf processes during senescence depends on the time of senescence. Rather than prolonging the growing season by enabling a delayed senescence, autumn anthocyanins in red maple in Ontario are important when senescence happens early, possibly due to the higher irradiance and greater danger of oxidative damage early in the season.

  14. Adaptive responses of Acer ginnala, Pyrus ussuriensis and Prunus davidiana seedlings to soil moisture stress

    WANGQing-cheng; SUNZhi-hu; ZHANGYan-dong

    2003-01-01

    One-year-old seedlings of Amur maple (Acer ginnala Maxim), Ussurian pear (Pyrus ussuriensis Maxim) and David peach (Prunus davidiana Carr) were planted in pots in greenhouse and treated with four different soil moisture contents (75.0%,61.1%, 46.4% and 35.4%). The results showed that net photosynthesis rate (NPR), transpiration rate (TR) and stomatal conductance (Sc) of seedlings of the three species decreased with the decease of soil moisture content, and Amur maple seedlings had the greatest change in those physiological indices, followed by Ussurian pear, David peach. Amur maple and Ussurian pear seedlings also presented a decrease tendency in water use efficiency (WUE) under lower soil moisture content, whereas this was reversed for David peach. Under water stress the biomass allocation to seedling root had a significant increase for all the experimental species. As to root/shoot ratio, Amur maple seedlings had the biggest increase, while David peach had the smaliest increase. The leaf plasticity of Amur maple seedlings was greater, the leaf size and total leaf area decreased significantly as the stress was intensified. No significant change of leaf size and total leaf area was found in seedlings of Ussurian pear and David peach. It was concluded that Amur maple was more tolerant to soil moisture stress in comparison with David peach and Ussurian pear.

  15. Effect of space flight on physiological indexes and antioxidant enzymes of Acer mono

    To investigate the effects of space flight on physiological indexes and antioxidant enzymes of Acer mono, seeds were divided into two groups, one was treated by carrying on Shijian No.8 breeding satellite for 15 d, and the other was kept on the ground as controls. 5 years old seedlings that derived from the seeds of space flight and the seeds of ground control were chosen as materials, then the growth characteristics, photosynthetic characteristics, soluble protein content and antioxidant enzymes activities were analyzed. The results showed that the plant growth, net photosynthetic rate (Pn), chlorophyll content, superoxide dismutase (SOD) activity and soluble protein content of seedlings after space flight were much higher than those of ground control. However, the changes of malondialdehyde (MDA) content, peroxidase (POD), transpiration rate (Tr), intercellular carbon dioxide concentration (Ci) and stomatal conductance (Gs) were not significantly changed. The net photosynthetic rate (Pn), as well as the plant growth of seedlings after space flight were higher than those of the control. The improved ability of photosynthesis may be one of the reasons that seedlings from seeds of space flight have higher speed of growth. (authors)

  16. COENOTICAL CHAINS OF ACER PLATANOIDES AND QUERCUS ROBUR IN THE FORESTS OF NOVGOROD-SEVERSKOYE POLESYE

    Skliar V. G.

    2012-12-01

    Full Text Available We summarized information on association of small undergrowth of Norway maple (Acer platanoides L. and English oak (Quercus robur L. under the canopy of the forest with plants that form the grass-shrub layer within Novgorod-Severskoye Polesye. We founded that the association at certain extent depends on the type of population behavior of undergrowth and grasses. Small undergrowth of A. platanoides being the tolerant species according to the type of population behavior demonstrates negative association with the herbs that have high competitive ability. The pattern of association of A. platanoides with tolerant species depends on their vegetative mobility: the maple has positive association with species with no vegetative mobility and positive and negative association with species characterized by high extent of vegetative mobility. The undergrowth of Q. robur which is the competitive species due to population behavior shows positive association with the herbs that have high competitive ability. We estimated the coenotic parameters that are required for successful resumption of maple and oak in the region of research. We also shown that coenotic optimum for A. platanoides corresponds to the environment with weak intensity of competition in the living soil cover with thin grass layer and density of coverage does not exceed 50%. Q. robur has coenotic optimum among habitats in the herbaceous layer with domination of green moss and (or Convallaria majalis L., Fragaria vesca L. with no grains and density of coverage in living ground cover not more than 60%.

  17. Spread intensity and invasiveness of sycamore maple (Acer pseudoplatanus L. in Lithuanian forests

    Straigyte L

    2015-03-01

    Full Text Available The primary objectives of this study were to estimate seedling abundance, spread intensity, and invasiveness of sycamore maple (Acer pseudoplatanus L. in Lithuanian forests. The species was introduced to Lithuania in 1802, and since then has subsequently become gradually invasive. Seedling understory abundance, colonization and dispersal were investigated in six forest blocks covering the principal sycamore distribution areas in southwestern Lithuania. Seedlings height and densities in the undestory were evaluated, and seedlings assigned to four height groups. Species invasiveness was estimated applying the Pest Plant Prioritization Process (PPPP, based on the Analytic Hierarchy Process (AHP method. Results showed the average spread distance from the parent tree was 257 m, with a mean seedling number per hectare of 2064. Sycamore maple invasive score was 0.6426 (range: 0-1, the current relative to potential distribution rating was 0.57, and the social, environmental, and economic impact score was 0.1682. Such values were used to assess the Pest Plant Score for sycamore maple, obtaining a value (0.3537 lower than expectations (0.5. Results indicated that the species exhibits invasive properties and a rapid spread in the study area. Some implications of the above results in view of the upcoming climate change and the use of sycamore maple in Lithuanian forest plantations are discussed.

  18. Testing the 'rare pit' hypothesis for xylem cavitation resistance in three species of Acer.

    Christman, Mairgareth A; Sperry, John S; Adler, Frederick R

    2009-01-01

    Eudicot angiosperms with greater vulnerability to xylem cavitation tend to have vessels with greater total area of inter-vessel pits, which inspired the 'rare pit' hypothesis: the more pits per vessel, by chance the leakier will be the vessel's single air-seeding pit and the lower the air-seeding threshold for cavitation to spread between vessels. Here, we demonstrate the feasibility of the hypothesis, using probability theory to model the axial propagation of air through air-injected stems. In the presence of rare, leaky pits, air-seeding pressures through short stems with few vessel ends in series should be low; pressures should increase in longer stems as more end-walls must be breached. Measurements on three Acer species conformed closely to model predictions, confirming the rare presence of leaky pits. The model indicated that pits air-seeding at or below the mean cavitation pressure (MCP) occurred at similarly low frequencies in all species. Average end-wall air-seeding pressures predicted by the model closely matched species' MCPs. Differences in species' vulnerability were primarily attributed to differences in frequency of the leakiest pits rather than pit number or area per vessel. Adjustments in membrane properties and extent of pitting per vessel apparently combine to influence cavitation resistance across species. PMID:19434805

  19. Proteomic Analysis of Embryogenesis and the Acquisition of Seed Dormancy in Norway Maple (Acer platanoides L.

    Aleksandra Maria Staszak

    2014-06-01

    Full Text Available The proteome of zygotic embryos of Acer platanoides L. was analyzed via high-resolution 2D-SDS-PAGE and MS/MS in order to: (1 identify significant physiological processes associated with embryo development; and (2 identify changes in the proteome of the embryo associated with the acquisition of seed dormancy. Seventeen spots were identified as associated with morphogenesis at 10 to 13 weeks after flowering (WAF. Thirty-three spots were associated with maturation of the embryo at 14 to 22 WAF. The greatest changes in protein abundance occurred at 22 WAF, when seeds become fully mature. Overall, the stage of morphogenesis was characterized by changes in the abundance of proteins (tubulins and actin associated with the growth and development of the embryo. Enzymes related to energy supply were especially elevated, most likely due to the energy demand associated with rapid growth and cell division. The stage of maturation is crucial to the establishment of seed dormancy and is associated with a higher abundance of proteins involved in genetic information processing, energy and carbon metabolism and cellular and antioxidant processes. Results indicated that a glycine-rich RNA-binding protein and proteasome proteins may be directly involved in dormancy acquisition control, and future studies are warranted to verify this association.

  20. Sensitivity of leaf size and shape to climate within Acer rubrum and Quercus kelloggii.

    Royer, Dana L; McElwain, Jennifer C; Adams, Jonathan M; Wilf, Peter

    2008-01-01

    * Variation in the size and shape (physiognomy) of leaves has long been correlated to climate, and paleobotanists have used these correlations to reconstruct paleo-climate. Most studies focus on site-level means of largely nonoverlapping species sets. The sensitivity of leaf shape to climate within species is poorly known, which limits our general understanding of leaf-climate relationships and the value of intraspecific patterns for paleoclimate reconstructions. * The leaf physiognomy of two species whose native North American ranges span large climatic gradients (Acer rubrum and Quercus kelloggii) was quantified and correlated to mean annual temperature (MAT). Quercus kelloggii was sampled across a wide elevation range, but A. rubrum was sampled in strictly lowland areas. * Within A. rubrum, leaf shape correlates with MAT in a manner that is largely consistent with previous site-level studies; leaves from cold climates are toothier and more highly dissected. By contrast, Q. kelloggii is largely insensitive to MAT; instead, windy conditions with ample plant-available water may explain the preponderance of small teeth at high elevation sites, independent of MAT. * This study highlights the strong correspondence between leaf form and climate within some species, and demonstrates that intraspecific patterns may contribute useful information towards reconstructing paleoclimate. PMID:18507771

  1. Hallazgo de un endocarpo del genero Acer en niveles del Cretácico superior del embalse de Pedrezuela (Guadalix de la Sierra

    Lesiak, M. A.

    1996-12-01

    Full Text Available In this paper is described and discussed an endocarp of Acer genus that exhibits a morphology like the living species A. buergerianum Miquel. The fruit was met in the upper part of Cretaceous series from the Pedrezuela barrier of Madrid Community. We propose a new denomination for the plant that contains this endocarp: Acer palaeobuergerianum n. fsp. This name has only taxonomic value. The prefix is give in order to the age and -buergerianum by its similarity with the actual species.Se describe y discute un endocarpo fósil perteneciente al género Acer, encontrado en el Cretácico superior del embalse de Pedrezuela (Madrid. Este fruto muestra una marcada semejanza con los endocarpos de la especie actual Acer buergerianum Miquel. Se propone una nueva denominación, con valor taxonómico, para la planta: Acer palaeobuergerianum n. fsp. El prefijo palaeo sugiere su edad y la denominación - buergerianum su semejanza morfológica con la especie actual.

  2. Spectrochemical analysis of sycamore (Acer pseudoplatanus) leaves for environmental health monitoring.

    Ord, James; Butler, Holly J; McAinsh, Martin R; Martin, Francis L

    2016-05-10

    Terrestrial plants are ideal sentinels of environmental pollution, due to their sedentary nature, abundance and sensitivity to atmospheric changes. However, reliable and sensitive biomarkers of exposure have hitherto been difficult to characterise. Biospectroscopy offers a novel approach to the derivation of biomarkers in the form of discrete molecular alterations detectable within a biochemical fingerprint. We investigated the application of this approach for the identification of biomarkers for pollution exposure using the common sycamore (Acer pseudoplatanus) as a sentinel species. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was used to interrogate leaf tissue collected from three sites exposed to different levels of vehicle exhaust emissions. Following multivariate analysis of acquired spectra, significant biochemical alterations were detected between comparable leaves from different sites that may constitute putative biomarkers for pollution-induced stress. These included differences in carbohydrate and nucleic acid conformations, which may be indicative of sub-lethal exposure effects. We also observed several corresponding spectral alterations in both the leaves of A. pseudoplatanus exposed to ozone pollution under controlled environmental conditions and in leaves infected with the fungal pathogen Rhytisma acerinum, indicating that some stress-induced changes are conserved between different stress signatures. These similarities may be indicative of stress-induced reactive oxygen species (ROS) generation, although further work is needed to verify the precise identity of infrared biomarkers and to identify those that are specific to pollution exposure. Taken together, our data clearly demonstrate that biospectroscopy presents an effective toolkit for the utilisation of higher plants, such as A. pseudoplatanus, as sentinels of environmental pollution. PMID:27068098

  3. Nuclear microsatellite markers for population genetic studies in sugar maple (Acer saccharum Marsh.

    Sudhir Khodwekar

    2015-12-01

    Full Text Available A set of seven new nuclear microsatellite markers (nSSRs was developedfor sugar maple (Acer saccharum Marsh. using paired-end Illumina sequencing. Out of 96 primers screened in a panel of six unrelated individuals, seven markers amplified polymorphic products. The utility of these markers, in addition to six already published microsatellites, for genetic variation and gene flow studies was assessed. Out of the seven newly developed markers, three amplified multiple fragments and were interpreted as dominant (absence/presence markers, while four markers amplified a maximum of two amplification products per sample. The six published microsatellites and three of the four newly developed markers showed regular segregation in an open-pollinated single tree progeny. Observed heterozygosity (Ho and expected heterozygosity (He in 48 individuals from one population ranged from 0.436 to 0.917 and from 0.726 to 0.894, respectively. Dominant markers revealed 64 variable positions and moderate genetic variation within the population (He = 0.102, Shannon’s I = 0.193. Paternity analyses in the program CERVUS at co-dominant markers showed effective dispersal of pollen in the sugar maple population both at 95% and 80% confidence levels. Dependent on the confidence level, the mean pollen dispersal distance within the population ranged from 33.25 m to 38.75 m and gene flow from utside the stand from 78% to 82%. The absence of fine-scale Spatial Genetic Structure (SGS suggested effective dispersal of both seeds and pollen.

  4. Changes in the ascorbate-glutathione system during storage of recalcitrant seeds of Acer saccharinum L.

    Ewelina Ratajczak

    2011-04-01

    Full Text Available Two seed lots of Acer saccharinum (recalcitrant, with an initial moisture content of 50% and 55%, were stored at +3oC for 6 months. After this time, their viability (measured as germinability reached 100% and 30%, respectively. In embryo axes and cotyledons extracted from seeds, two major low molecular antioxidants were assayed: ascorbate (ASA and DHA and glutathione (GSH and GSSG; and activities of enzymes of the ascorbate-glutathione cycle were measured: ascorbate peroxidase (APO (E.C. 1.11.1.11, monodehydroascorbate reductase (MR (E.C. 1.6.5.4, dehydroascorbate reductase (DHAR (E.C. 1.8.5.1, and glutathione reductase (GR (E.C. 1.6.4.2.. GSH and GSSG contents of embryo axes of stored seeds decreased, as compared to the control (fresh, non-stored seeds, but a larger decrease was observed in seeds with 30% viability. In cotyledons, a particularly high increase in the GSH content in relation to the control was observed in seeds with 100% viability, while the GSSG content was significantly lower in both stored seed lots than in the control. The ASA level was twice as high in seeds with 30% viability as in the control, both in embryo axes and in cotyledons. The activity of enzymes of the ascorbate-glutathione cycle was higher in embryo axes than in cotyledons. In embryo axes of seeds with 100% viability, enzyme activities were slightly lower than in the control, while in those of seeds with 30% viability, their activities were higher than in the control. The observed changes in activities of enzymes of the ascorbate-glutathione cycle and in ascorbate and glutathione levels suggest that the stored seeds of A. saccharinum have an active antioxidant system, which plays an important role in maintaining their viability during storage.

  5. Relationship between leaf optical properties, chlorophyll fluorescence and pigment changes in senescing Acer saccharum leaves.

    Junker, Laura Verena; Ensminger, Ingo

    2016-06-01

    The ability of plants to sequester carbon is highly variable over the course of the year and reflects seasonal variation in photosynthetic efficiency. This seasonal variation is most prominent during autumn, when leaves of deciduous tree species such as sugar maple (Acer saccharum Marsh.) undergo senescence, which is associated with downregulation of photosynthesis and a change of leaf color. The remote sensing of leaf color by spectral reflectance measurements and digital repeat images is increasingly used to improve models of growing season length and seasonal variation in carbon sequestration. Vegetation indices derived from spectral reflectance measurements and digital repeat images might not adequately reflect photosynthetic efficiency of red-senescing tree species during autumn due to the changes in foliar pigment content associated with autumn phenology. In this study, we aimed to assess how effectively several widely used vegetation indices capture autumn phenology and reflect the changes in physiology and photosynthetic pigments during autumn. Chlorophyll fluorescence and pigment content of green, yellow, orange and red leaves were measured to represent leaf senescence during autumn and used as a reference to validate and compare vegetation indices derived from leaf-level spectral reflectance measurements and color analysis of digital images. Vegetation indices varied in their suitability to track the decrease of photosynthetic efficiency and chlorophyll content despite increasing anthocyanin content. Commonly used spectral reflectance indices such as the normalized difference vegetation index and photochemical reflectance index showed major constraints arising from a limited representation of gradual decreases in chlorophyll content and an influence of high foliar anthocyanin levels. The excess green index and green-red vegetation index were more suitable to assess the process of senescence. Similarly, digital image analysis revealed that vegetation

  6. Xyloglucan biosynthesis by Golgi membranes from suspension-cultured sycamore (Acer pseudoplatanus) cells

    Xyloglucan is a major hemicellulose polysaccharide in plant cell walls. Biosynthesis of such cell wall polysaccharides is closely linked to the process of plant cell growth and development. Xyloglucan polysaccharides consist of a β-1,4 glucan backbone synthesized by xyloglucan synthase and sidechains of xylose, galactose, and fucose added by other transferase enzymes. Most plant Golgi and plasma membranes also contain glucan synthases I ampersand II, which make β-1,4 and β-1,3 glucans, respectively. All of these enzymes have very similar activities. Cell walls on suspension-cultured cells from Acer pseudoplatanus (sycamore maple) were enzymatically softened prior to cell disruption by passing through a 30 μm nylon screen. Cell membranes from homogenates were separated by ultracentrifugation on top-loaded or flotation sucrose density gradients. Samples were collected by gradient fractionation and assayed for membrane markers and xyloglucan and glucan synthase activities. Standard marker assays (cyt. c reductase for eR, IDPase ampersand UDPase for Golgi, and eosin 5'-malelmide binding for plasma membrane) showed partial separation of these three membrane types. Golgi and plasma membrane markers overlapped in most gradients. Incorporation of 14C-labeled sugars from UDP-glucose and UDP-xylose was used to detect xyloglucan synthase, glucan synthases I ampersand II, and xylosyl transferase in Golgi membrane fractions. These activities overlapped, although distinct peaks of xyloglucan synthase and xylosyl transferase were found. Ca++ had a stimulatory effect on glucan synthases I ampersand II, while Mn++ had an inhibitory effect on glucan synthase I in the presence of Ca++. The similarity of these various synthase activities demonstrates the need for careful structural characterization of newly synthesized polysaccharides

  7. Root vitality of Fagus sylvatica L., Quercus petraea Liebl. and Acer pseudoplatanus L. in mature mixed forest stand

    Grygoruk, Dorota

    2016-01-01

    The main task of the present study was to investigate the root vitality of common beech Fagus sylvatica L., sessile oak Quercus petraea Liebl. and sycamore maple Acer pseudoplatanus L. in the optimal growth conditions in south-western Poland. The study was carried out in 130-year-old mixed stand located within natural range of studied tree species. The density of roots (g/100 cm3 of soil) and biomass of fine roots (g/m2) in topsoil layers (0–5 cm, 5–15 cm) were determined in the tree biogroup...

  8. 中华蜜蜂化学感受蛋白AcerCSP3的配基结合功能分析%Molecular binding characterization with chemical ligands of a chemosensory protein AcerCSP3 in the Chinese honeybee, Apis cerana cerana Fabricius ( Hymenoptera: Apidae)

    李红亮; 张林雅; 倪翠侠; 商晗武

    2011-01-01

    为研究中华蜜蜂和Apis cerana cerana化学感受蛋白AcerCSP3在化学感受系统中的生理功能,本实验通过对AcerCSP3进行原核表达、分离纯化后,利用荧光法研究了体外重组AcerCSP3与1-NPN以及候选化学配基的结合特征.Scatchard方程显示AcerCSP3与1-NPN的解离常数KD为8.29 μmol/L,结合位点数约等于1.在候选配基竞争1-NPN与AcerCSP3结合的实验中,5种配基均能在200 μmol/L浓度下使1-NPN的相对荧光强度下降至50%以下.其中β-紫罗兰酮其至能使1-NPN的相对荧光强度下降至10%左右,表明候选配基均与AcerCSP3有较强的结合能力,而3,4-二甲基苯甲醛与中蜂AcerCSP3的结合能力最强,KD达到18.77 μmol/L.本研究所用化学配基均为植物花与叶片的挥发性的次生代谢产物,表明AcerCSP3可能作为中蜂化学感受系统的一部分,在其搜寻某些植物花粉蜜源时作为气味分子运载体发挥一定的作用.%In order to clarify the physiological function of AcerCSP3, a chemosensory protein (CSP) in Apis cerana cerana, the recombinant protein AcerCSP3 was successfully expressed in a optimized prokaryotic expression system, and the binding properties of the purified AcerCSP3 with 1-NPN was then investigated.Scatchard plot analysis indicated that the dissociation constant between 1-NPN and AcerCSP3 was 8.29 μmol/L and the binding site number was about one. In the competitive binding assays, all the five candidate ligands at the concentration of 200 μmol/L reduced the relative fluorescence intensity of 1-NPN by more than 50% , with β-ionone causing 90% reduction in the relative fluorescence intensity, suggesting that all the tested ligands have strong binding capability with AcerCSP3. 3, 4-Dimethylbenzaldehyde had the strongest binding capability with a dissociation constant as high as 18.77 μmol/L. All the candidate chemical ligands are plant volatile secondary metabolites, indicating that AcerCSP3 may act as a carier for

  9. Effect of Alnus subcordata, Acer insigne and Sequoia sempervirens plantations on plant diversity in Hyrcanian forest of Iran

    FATEMEH GHEIBI

    2015-04-01

    Full Text Available Gheibi F, Akbarinia M, Kooch Y. 2015. Effect of Alnus subcordata, Acer insigne and Sequoia sempervirens plantations on plant diversity in Hyrcanian forest of Iran. Biodiversitas 16: 10-15. Forest plantation is a common action in order to restore the degraded forests in Hyrcanian forests of Iran. This study compares the plant biodiversity in four 25-year-old stands of plantation, adjacent understory of alder (Alnus subcordata C. A. Mey., maple (Acer insigne Boiss., sequoia or red wood (Sequoia sempervirens (D. Don Endl. and mixed stand (maple and sequoia, located in Salmanshahr of Mazandaran Province, northern Iran. Research carried out in, 10 sample plots with 20m × 20m area which taken by systematic-random in each plantation. All understory species were identified, recorded and then the biodiversity indices (diversity, richness and evenness were calculated. Our findings show that the planted species had significant effects on understory diversity. Statistical comparisons revealed that the highest and lowest diversity (Simpson and Shanon-Winer and richness (Margalef and Menhinic indices occurred in sequoia and alder stands, respectively. The evenness indices (Camargo and Smith-Wilson were significantly greater in maple, sequoia and mixed stands compared with the alder type. As a conclusion, floristic change trends were different according to the planted tree species. A good understanding of the complexity of vegetation processes requires long-term monitoring of vegetation change.

  10. AcerDET-2.0: a particle level fast simulation and reconstruction package for phenomenological studies on high p_T physics at LHC

    Mikos, Patryk

    2015-01-01

    The fortran version of the AcerDET package has been published in [1], and used in the multiple publications on the predictions for physics at LHC. The package provides, starting from list of particles in the event, the list of reconstructed jets, isolated electrons, muons, photons and reconstructed missing transverse energy. The AcerDET represents a simplified version of the package called ATLFAST, used since several years within ATLAS Collaboration. In the fast simulation implemented in AcerDET, some functionalities of ATLFAST are absent, but the most crucial detector effects are implemented and the parametrisations are largely simplified. Therefore it is not representing details neither of ATLAS nor CMS detectors. This short paper documents a new C++ implementation of the same algorithms as used in [1]. We believe that the package can be well adequate for some feasibility studies of the high p_T physics at LHC and at planned ppFCC. The further evolution of this code is planned. [1] E. Richter-Was, AcerDET: ...

  11. Evaluation of a single application of Neonicotnoid and multi-application contact insecticides for flatheaded borer management in field grown Acer rubrum L. cultivars

    Two trials evaluated insecticides for flatheaded borer (Chrysobothris femorata [Olivier]) control and red maple (Acer rubrum L.) cultivar growth over a 4-year period. Soil-applied systemic insecticides (acephate, imidacloprid, clothianidin, dinotefuran, and thiamethoxam) and trunk-applied contact i...

  12. Klíčení semen javoru jasanolistého (Acer negundo) a postup jeho invaze v ČR

    Hrázský, Z.; Mihulka, Stanislav

    2008-01-01

    Roč. 43, Mater. 23 (2008), s. 151-162. ISSN 1212-3323. [Rostlinné invaze v ČR: situace, výzkum a management. Praha, 30.11.2007-01.12.2007] Institutional research plan: CEZ:AV0Z60050516 Keywords : Acer negundo * invasion * mapping of distributiion Subject RIV: EF - Botanics

  13. Effect of gender on sap-flux-scaled transpiration in a dominant riparian tree species: Box elder (Acer negundo)

    Hultine, K. R.; Bush, S. E.; West, A. G.; Ehleringer, J. R.

    2007-09-01

    Acer negundo is a dioecious riparian tree species with a spatial segregation of the sexes along soil moisture gradients. Females are typically more common in wet sites along streams (typically F/M ≈ 1.6), whereas males are more common in drier sites away from streams (typically F/M ≈ 0.6). Spatial segregation between sexes may develop because of the higher reproductive cost in females compared to males. If so, female Acer negundo trees would be under stronger selection to maximize resource uptake, and would therefore likely occur at greater frequencies in high resources sites (i.e., along streamsides), and increase rates of resource acquisition (i.e., water and nutrients). The spatial segregation of the sexes leads to the hypothesis that male and female individuals have varying influence on ecosystem evapotranspiration. To address this, stem sap flux was measured on mature streamside (≤1 m from stream channel) and nonstreamside (>1 m from stream channel) male and female Acer negundo trees occurring in Red Butte Canyon near Salt Lake City, Utah, during the 2004 growing season. Despite having similar predawn and midday water potentials, sap flux density was 76% higher in streamside female trees than in males (P < 0.0001), while sap flux density was 19% greater in nonstreamside female trees compared to males (P < 0.0001). Mean daily sap flux density of all A. negundo populations was highly correlated with mean daily vapor pressure deficit (P < 0.0001), and was moderately correlated with mean daily photosynthetic active radiation (P = 0.0263). At the watershed scale, nonstreamside male and female A. negundo trees contributed 20 and 21% respectively to the estimated 1.7 mm d-1 transpiration flux from dominant riparian vegetation away from streamsides (estimated from scaled sap flux measurements of all dominant riparian tree species in Red Butte Canyon). Male and female A. negundo trees contributed 31 and 46% respectively of the estimated 8.0 mm d-1 transpiration

  14. Effect of gender on sap-flux-scaled transpiration in a dominant riparian tree species: Box elder (Acer negundo)

    Hultine, K. R.; Bush, S. E.; West, A. G.; Ehleringer, J. R.

    2007-09-01

    Acer negundo is a dioecious riparian tree species with a spatial segregation of the sexes along soil moisture gradients. Females are typically more common in wet sites along streams (typically F/M ≈ 1.6), whereas males are more common in drier sites away from streams (typically F/M ≈ 0.6). Spatial segregation between sexes may develop because of the higher reproductive cost in females compared to males. If so, female Acer negundo trees would be under stronger selection to maximize resource uptake, and would therefore likely occur at greater frequencies in high resources sites (i.e., along streamsides), and increase rates of resource acquisition (i.e., water and nutrients). The spatial segregation of the sexes leads to the hypothesis that male and female individuals have varying influence on ecosystem evapotranspiration. To address this, stem sap flux was measured on mature streamside (≤1 m from stream channel) and nonstreamside (>1 m from stream channel) male and female Acer negundo trees occurring in Red Butte Canyon near Salt Lake City, Utah, during the 2004 growing season. Despite having similar predawn and midday water potentials, sap flux density was 76% higher in streamside female trees than in males (P active radiation (P = 0.0263). At the watershed scale, nonstreamside male and female A. negundo trees contributed 20 and 21% respectively to the estimated 1.7 mm d-1 transpiration flux from dominant riparian vegetation away from streamsides (estimated from scaled sap flux measurements of all dominant riparian tree species in Red Butte Canyon). Male and female A. negundo trees contributed 31 and 46% respectively of the estimated 8.0 mm d-1 transpiration flux from dominant riparian vegetation adjacent to the stream channel. Results from this investigation show that the population structure of dioecious riparian trees has direct consequences on ecosystem ET, particularly along stream margins. Shifts in population structure therefore, may have profound

  15. The role of habitat factors in successful invasion of alien plant Acer negundo in riparian zones.

    Sikorski, Piotr; Sikorska, Daria

    2016-04-01

    Ash-leaved maple (Acer negundo) is one of the most invasive species occurring in riparian zones. The invasion is especially effective in disturbed areas, as the plant favours anthropogenic sites. The plant was also observed to be able to penetrate into sandy bars, also those separated from the land, inaccessible to people. It's removal is time-consuming and laborious, often involves damage done to sensitive vegetation and the results are doubtful, as the plant quickly regenerates. The invasion patterns and establishment of ash-leaved maple in natural ecosystems are poorly investigated. The aim of this study was to test how habitat factors such as: light availability, soil characteristics and competition contribute to ash-leaved maple effective colonization of natural sand bars free from anthropogenic pressure. In 2014 sand bars located in Vistula River Valley in Warsaw were inventoried and classified basing on their development stage as 1 - initial, 2 - unstable, 3 - stable. Apart from the occurrence of the invasive ash-leaved maple the plants competing with it were recognized and the percentage of the shoots of shrubs and herbaceous plants was estimated. PAR was measured at ground level and 1 meter above ground, the thickness of organic layer formed on the top of the sand was also measured as the indicator of sand bar development stage. The maple's survival in extremely difficult conditions resembles the strategy of willows and poplars naturally occurring in the riparian zones, which are well adapted to this environment. The success of invasion strongly depends on the plants establishment during sand bars initial stage of development. The seedlings growth correlates with the age of the sand bar (r1=0,41, r2=0,42 i r3=0,57). The colonization lasts for 4-6 years and the individuals start to cluster in bigger parches. After that period the maple turns into the phase of competition for space. Habitat factors such as shading (r2=0,41 i r3=0,51) and organic layer

  16. 桌面的3D诱惑——Acer Aspire GD245HQ显示器

    2010-01-01

    3D当前被炒得如火如萘,3D电影、3D电视机、3D投影机、3D相机、3D蓝光机,当然还有3D显示器,可以说3D已经在我们的周围无处不在,现在你可以轻轻松松地随时随地体验3D世界。坐在显示器前,戴上眼镜,让Acer GD245HQ 3D显示器为你带来身临其境的真切画面吧。

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

    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...

  18. Physiology and biochemistry of leaf bleaching in prematurely aging maple (Acer saccharinum L.) trees. II. Functional and molecular adjustment of PSII.

    Lepeduš, Hrvoje; Begović, Lidija; Mlinarić, Selma; Šimić, Domagoj; Štolfa, Ivna; Parađiković, Nada; Užarević, Zvonimir; Jurković, Vlatka; Cesar, Vera

    2011-01-01

    In the present study we aimed to investigate physiological and molecular mechanisms of photosynthetic performance decline in prematurely aged bleached leaves of silver maple (Acer saccharinum L.) trees. We used in vivo chlorophyll a fluorescence measurement to analyze changes in PSII photochemistry, relative abundance of photosynthetic proteins (D1, LHCII, Cytf and Rubisco LSU), relations between chlorophylls and their precursor protochlorophyllide as well as elemental composition of the l...

  19. The invasive alien leaf miner Cameraria ohridella and the native tree Acer pseudoplatanus: a fatal attraction?

    Péré, Christelle; Augustin, Sylvie; Ted C J Turlings; Kenis, Marc

    2012-01-01

    1. The horse-chestnut leaf miner Cameraria ohridella is an invasive moth in Europe and a serious pest of horse-chestnut Aesculus hippocastanum. The moth also occasionally attacks sycamore maple Acer pseudoplatanus, when situated beside infested horse-chestnuts. 2. The main objective of the present study was to provide an overview of the relationship between C. ohridella and A. pseudoplatanus and to determine whether C. ohridella has the potential to shift to this native tree. 3. In the fiel...

  20. Cytotoxicity and structure activity relationship studies of maplexins A-I, gallotannins from red maple (Acer rubrum).

    González-Sarrías, Antonio; Yuan, Tao; Seeram, Navindra P

    2012-05-01

    Maplexins A-I are a series of structurally related gallotannins recently isolated from the red maple (Acer rubrum) species. They differ in number and location of galloyl derivatives attached to 1,5-anhydro-glucitol. Here, maplexins A-I were evaluated for anticancer effects against human tumorigenic (colon, HCT-116; breast, MCF-7) and non-tumorigenic (colon, CCD-18Co) cell lines. The maplexins which contained two (maplexins C-D) or three (maplexins E-I) galloyl derivatives each, inhibited cancer cell growth while those with only one galloyl group (maplexins A-B) did not. Moreover, maplexins C-D showed greater antiproliferative effects than maplexins E-I (IC(50)=59.8-67.9 and 95.5-108.5 μM vs. 73.7-165.2 and 115.5-182.5 μM against HCT-116 and MCF-7 cells, respectively). Notably, the cancer cells were up to 2.5-fold more sensitive to the maplexins than the normal cells. In further mechanistic studies, maplexins C-D (at 75 μM concentrations) induced apoptosis and arrested cell cycle (in the S-phase) of the cancer cells. These results suggest that the number of galloyl groups attached to the 1,5-anhydro-glucitol moiety in these gallotannins are important for antiproliferative activity. Also, this is the first in vitro anticancer study of maplexins. PMID:22387705

  1. Acerogenin A, a natural compound isolated from Acer nikoense Maxim, stimulates osteoblast differentiation through bone morphogenetic protein action

    Research highlights: → Acerogenin A stimulated osteoblast differentiation in osteogenic cells. → Acerogenin A-induced osteoblast differentiation was inhibited by noggin. → Acerogenin A increased Bmp-2, Bmp-4 and Bmp-7 mRNA expression in MC3T3-E1 cells. → Acerogenin A is a candidate agent for stimulating bone formation. -- Abstract: We investigated the effects of acerogenin A, a natural compound isolated from Acer nikoense Maxim, on osteoblast differentiation by using osteoblastic cells. Acerogenin A stimulated the cell proliferation of MC3T3-E1 osteoblastic cells and RD-C6 osteoblastic cells (Runx2-deficient cell line). It also increased alkaline phosphatase activity in MC3T3-E1 and RD-C6 cells and calvarial osteoblastic cells isolated from the calvariae of newborn mice. Acerogenin A also increased the expression of mRNAs related to osteoblast differentiation, including Osteocalcin, Osterix and Runx2 in MC3T3-E1 cells and primary osteoblasts: it also stimulated Osteocalcin and Osterix mRNA expression in RD-C6 cells. The acerogenin A treatment for 3 days increased Bmp-2, Bmp-4, and Bmp-7 mRNA expression levels in MC3T3-E1 cells. Adding noggin, a BMP specific-antagonist, inhibited the acerogenin A-induced increase in the Osteocalcin, Osterix and Runx2 mRNA expression levels. These results indicated that acerogenin A stimulates osteoblast differentiation through BMP action, which is mediated by Runx2-dependent and Runx2-independent pathways.

  2. Interacting effects of warming and drought on regeneration and early growth of Acer pseudoplatanus and A. platanoides.

    Carón, M M; De Frenne, P; Brunet, J; Chabrerie, O; Cousins, S A O; De Backer, L; Decocq, G; Diekmann, M; Heinken, T; Kolb, A; Naaf, T; Plue, J; Selvi, F; Strimbeck, G R; Wulf, M; Verheyen, K

    2015-01-01

    Climate change is acting on several aspects of plant life cycles, including the sexual reproductive stage, which is considered amongst the most sensitive life-cycle phases. In temperate forests, it is expected that climate change will lead to a compositional change in community structure due to changes in the dominance of currently more abundant forest tree species. Increasing our understanding of the effects of climate change on currently secondary tree species recruitment is therefore important to better understand and forecast population and community dynamics in forests. Here, we analyse the interactive effects of rising temperatures and soil moisture reduction on germination, seedling survival and early growth of two important secondary European tree species, Acer pseudoplatanus and A. platanoides. Additionally, we analyse the effect of the temperature experienced by the mother tree during seed production by collecting seeds of both species along a 2200-km long latitudinal gradient. For most of the responses, A. platanoides showed higher sensitivity to the treatments applied, and especially to its joint manipulation, which for some variables resulted in additive effects while for others only partial compensation. In both species, germination and survival decreased with rising temperatures and/or soil moisture reduction while early growth decreased with declining soil moisture content. We conclude that although A. platanoides germination and survival were more affected after the applied treatments, its initial higher germination and larger seedlings might allow this species to be relatively more successful than A. pseudoplatanus in the face of climate change. PMID:24750437

  3. Effect of desiccation on the dynamics of genome-wide DNA methylation in orthodox seeds of Acer platanoides L.

    Plitta, Beata P; Michalak, Marcin; Bujarska-Borkowska, Barbara; Barciszewska, Mirosława Z; Barciszewski, Jan; Chmielarz, Paweł

    2014-12-01

    5-methylcytosine, an abundant epigenetic mark, plays an important role in the regulation of plant growth and development, but there is little information about stress-induced changes in DNA methylation in seeds. In the present study, changes in a global level of m5C were measured in orthodox seeds of Acer platanoides L. during seed desiccation from a WC of 1.04 to 0.05-0.06 g H2O g g(-1) dry mass (g g(-1)). Changes in the level of DNA methylation were measured using 2D TLC e based method. Quality of desiccated seeds was examined by germination and seedling emergence tests. Global m5C content (R2)increase was observed in embryonic axes isolated from seeds collected at a high WC of 1.04 g g(-1) after their desiccation to significantly lower WC of 0.17 and 0.19 g g(-1). Further desiccation of these seeds to a WC of 0.06 g g(-1), however, resulted in a significant DNA demethylation to R2 ¼ 11.52-12.22%. Similar m5C decrease was observed in seeds which undergo maturation drying on the tree and had four times lower initial WC of 0.27 g g(-1) at the time of harvest, as they were dried to a WC of 0.05 g g(-1). These data confirm that desiccation induces changes in seed m5C levels. Results were validated by seed lots derived from tree different A. platanoides provenances. It is plausible that sine wave-like alterations in m5C amount may represent a specific response of orthodox seeds to drying and play a relevant role in desiccation tolerance in seeds. PMID:25394802

  4. Acerogenin A, a natural compound isolated from Acer nikoense Maxim, stimulates osteoblast differentiation through bone morphogenetic protein action

    Kihara, Tasuku [Section of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Section of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Global Center of Excellence (GCOE) Program, International Research Center for Molecular Science in Tooth and Bone Diseases, Tokyo Medical and Dental University, Tokyo (Japan); Ichikawa, Saki [Section of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Yonezawa, Takayuki; Lee, Ji-Won [Research Institute for Biological Functions, Chubu University, Kasugai, Aichi (Japan); Akihisa, Toshihiro [College of Science and Technology, Nihon University, Tokyo (Japan); Woo, Je Tae [Research Institute for Biological Functions, Chubu University, Kasugai, Aichi (Japan); Michi, Yasuyuki; Amagasa, Teruo [Section of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Yamaguchi, Akira, E-mail: akira.mpa@tmd.ac.jp [Section of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Global Center of Excellence (GCOE) Program, International Research Center for Molecular Science in Tooth and Bone Diseases, Tokyo Medical and Dental University, Tokyo (Japan)

    2011-03-11

    Research highlights: {yields} Acerogenin A stimulated osteoblast differentiation in osteogenic cells. {yields} Acerogenin A-induced osteoblast differentiation was inhibited by noggin. {yields} Acerogenin A increased Bmp-2, Bmp-4 and Bmp-7 mRNA expression in MC3T3-E1 cells. {yields} Acerogenin A is a candidate agent for stimulating bone formation. -- Abstract: We investigated the effects of acerogenin A, a natural compound isolated from Acer nikoense Maxim, on osteoblast differentiation by using osteoblastic cells. Acerogenin A stimulated the cell proliferation of MC3T3-E1 osteoblastic cells and RD-C6 osteoblastic cells (Runx2-deficient cell line). It also increased alkaline phosphatase activity in MC3T3-E1 and RD-C6 cells and calvarial osteoblastic cells isolated from the calvariae of newborn mice. Acerogenin A also increased the expression of mRNAs related to osteoblast differentiation, including Osteocalcin, Osterix and Runx2 in MC3T3-E1 cells and primary osteoblasts: it also stimulated Osteocalcin and Osterix mRNA expression in RD-C6 cells. The acerogenin A treatment for 3 days increased Bmp-2, Bmp-4, and Bmp-7 mRNA expression levels in MC3T3-E1 cells. Adding noggin, a BMP specific-antagonist, inhibited the acerogenin A-induced increase in the Osteocalcin, Osterix and Runx2 mRNA expression levels. These results indicated that acerogenin A stimulates osteoblast differentiation through BMP action, which is mediated by Runx2-dependent and Runx2-independent pathways.

  5. Genetic structure and hierarchical population divergence history of Acer mono var. mono in South and Northeast China.

    Chunping Liu

    Full Text Available Knowledge of the genetic structure and evolutionary history of tree species across their ranges is essential for the development of effective conservation and forest management strategies. Acer mono var. mono, an economically and ecologically important maple species, is extensively distributed in Northeast China (NE, whereas it has a scattered and patchy distribution in South China (SC. In this study, the genetic structure and demographic history of 56 natural populations of A. mono var. mono were evaluated using seven nuclear microsatellite markers. Neighbor-joining tree and STRUCTURE analysis clearly separated populations into NE and SC groups with two admixed-like populations. Allelic richness significantly decreased with increasing latitude within the NE group while both allelic richness and expected heterozygosity showed significant positive correlation with latitude within the SC group. Especially in the NE region, previous studies in Quercus mongolica and Fraxinus mandshurica have also detected reductions in genetic diversity with increases in latitude, suggesting this pattern may be common for tree species in this region, probably due to expansion from single refugium following the last glacial maximum (LGM. Approximate Bayesian Computation-based analysis revealed two major features of hierarchical population divergence in the species' evolutionary history. Recent divergence between the NE group and the admixed-like group corresponded to the LGM period and ancient divergence of SC groups took place during mid-late Pleistocene period. The level of genetic differentiation was moderate (FST  = 0.073; G'ST  = 0.278 among all populations, but significantly higher in the SC group than the NE group, mirroring the species' more scattered distribution in SC. Conservation measures for this species are proposed, taking into account the genetic structure and past demographic history identified in this study.

  6. Effect of Elevated Atmospheric CO2 and Temperature on Leaf Optical Properties and Chlorophyll Content in Acer saccharum (Marsh.)

    Carter, Gregory A.; Bahadur, Raj; Norby, Richard J.

    1999-01-01

    Elevated atmospheric CO2 pressure and numerous causes of plant stress often result in decreased leaf chlorophyll contents and thus would be expected to alter leaf optical properties. Hypotheses that elevated carbon dioxide pressure and air temperature would alter leaf optical properties were tested for sugar maple (Acer saccharum Marsh.) in the middle of its fourth growing season under treatment. The saplings had been growing since 1994 in open-top chambers at Oak Ridge, Tennessee under the following treatments: 1) Ambient CO2 pressure and air temperature (control); 2) CO2 pressure approximately 30 Pa above ambient; 3) Air temperatures 3 C above ambient; 4) Elevated CO2 and air temperature. Spectral reflectance, transmittance, and absorptance in the visible spectrum (400-720 nm) did not change significantly (rho = 0.05) in response to any treatment compared with control values. Although reflectance, transmittance, and absorptance at 700 nm correlated strongly with leaf chlorophyll content, chlorophyll content was not altered significantly by the treatments. The lack of treatment effects on pigmentation explained the non-significant change in optical properties in the visible spectrum. Optical properties in the near-infrared (721-850 nm) were similarly unresponsive to treatment with the exception of an increased absorptance in leaves that developed under elevated air temperature alone. This response could not be explained by the data, but might have resulted from effects of air temperature on leaf internal structure. Results indicated no significant potential for detecting leaf optical responses to elevated CO2 or temperature by the remote sensing of reflected radiation in the 400-850 nm spectrum.

  7. Molecular cloning, characterization, and expression pattern of chemosensory protein 1 gene (Acer-CSP1) in the Chinese honeybee, Apis cerana cerana (Hymenoptera: Apidae)%中华蜜蜂化学感受蛋白基因Acer-CSP1克隆与表达特征分析

    李红亮; 倪翠侠; 姚瑞; 高其康; 商晗武

    2010-01-01

    化学感受蛋白(ehemosensory proteins,CSPs)是昆虫化学感受系统中重要的组成部分之一.本研究克隆了中华蜜蜂Apis cerazm cerana化学感受蛋白基因Acer-CSP1,其核苷酸全长351 bp(GenBank登录号为FJ157352),编码116个氨基酸残基,预测蛋白分子量为13.85 kD,等电点为4.89,且含有4个保守的半胱氨酸残基,均符合昆虫CSPs的一般特征,且与意蜂CSP1基因具有99.1%的相似性,与其他昆虫也有45.3%~68.0%的相似性.利用2-△△C1法及绝对定昔法的real-time PCR技术对Acer-CSP1在中蜂不同器官表达特征进行了研究,得出的一致结论为Acer-CSP1显著水平地高丰度表达于中华蜜蜂触角,其次大量表达于头部.由于触角为中华蜜蜂最主要的嗅觉器官,而头部则具有发达的感觉神经系统和味觉系统,这也提示Acer-CSP1极有可能参与中华蜜蜂的嗅觉以及其他化学感受功能.

  8. Disseny i càlcul d'una màquina perforadora i copiadora de perfils interiors per a peces d'acer ràpid

    Canela i Gilabert, Xavier

    2005-01-01

    A partir d'un prototipus creat per a la realització de proves per a l'obtenció de perfils interiors en peces d'acer ràpid, el projecte contempla o té l’objectiu de dissenyar i calcular una nova màquina perforadora i copiadora amb la mateixa funcionalitat que el prototipus esmentat. L’antiga màquina va ser creada unes dues dècades enrere pel propietari d’una empresa especialitzada en la fabricació d’eines, segons normativa DIN i especials, d’acer ràpid pel sector de la tornil...

  9. Effects of forest fragmentation on the mating system of a cool-temperate heterodichogamous tree Acer mono

    Satoshi Kikuchi

    2015-01-01

    Full Text Available Pollination is a key process for reproduction and gene flow in flowering plants. Anthropogenic habitat fragmentation, however, can disrupt plant–pollinator interactions, and may have a negative impact on the reproductive success and population viability of entomophilous plants. Heterodichogamous plants containing protandrous and protogynous individuals within a population may be susceptible to habitat fragmentation due to a lack of available mating partners. In this study, we investigated the effects of forest fragmentation on the mating system in the heterodichogamous plant Acer mono, a major constituent of cool-temperate deciduous forests in Japan. Microsatellite analysis was applied to 212 adult trees and 17 seed families from continuous and fragmented forests. Dispersal kernel modeling using the neighborhood model indicated that pollen dispersal of A. mono was highly fat-tailed. The estimated parameters of the model suggested that the siring success of a pollen donor increased approximately fivefold, with a 100 cm increase in its diameter at breast height (DBH, and that disassortative mating was five times more frequent than assortative mating. The mating system parameters of each mother tree, outcrossing rate (tm, biparental inbreeding (tm−ts, and paternity correlation (rpm varied among sites and conditions, depending on the local density of potential pollen donors. Whereas A. mono was effectively outcrossed (tm=0.901, tm−ts=0.052, and the number of effective sires was 1/rpm=14.93 in the continuous forest, clumped trees within the fragmented forest showed increased biparental inbreeding and reduced pollen pool genetic diversity (tm=0.959, tm−ts=0.245,1/rpm=1.742 as a result of localized mating combined with spatial genetic structures. In contrast, the isolated trees had a higher selfing rate, but the pollen pool diversity was maintained (tm=0.801, tm−ts=0.022, and 1/rpm=15.63 due to frequent long-distance pollination. These

  10. Potential of two submontane broadleaved species (Acer opalus, Quercus pubescens) to reveal spatiotemporal patterns of rockfall activity

    Favillier, Adrien; Lopez-Saez, Jérôme; Corona, Christophe; Trappmann, Daniel; Toe, David; Stoffel, Markus; Rovéra, Georges; Berger, Frédéric

    2015-10-01

    Long-term records of rockfalls have proven to be scarce and typically incomplete, especially in increasingly urbanized areas where inventories are largely absent and the risk associated with rockfall events rises proportionally with urbanization. On forested slopes, tree-ring analyses may help to fill this gap, as they have been demonstrated to provide annually-resolved data on past rockfall activity over long periods. Yet, the reconstruction of rockfall chronologies has been hampered in the past by the paucity of studies that include broadleaved tree species, which are, in fact, quite common in various rockfall-prone environments. In this study, we test the sensitivity of two common, yet unstudied, broadleaved species - Quercus pubescens Willd. (Qp) and Acer opalus Mill. (Ao) - to record rockfall impacts. The approach is based on a systematic mapping of trees and the counting of visible scars on the stem surface of both species. Data are presented from a site in the Vercors massif (French Alps) where rocks are frequently detached from Valanginian limestone and marl cliffs. We compare recurrence interval maps obtained from both species and from two different sets of tree structures (i.e., single trees vs. coppice stands) based on Cohen's k coefficient and the mean absolute error. A total of 1230 scars were observed on the stem surface of 847 A. opalus and Q. pubescens trees. Both methods yield comparable results on the spatial distribution of relative rockfall activity with similar downslope decreasing recurrence intervals. Yet recurrence intervals vary significantly according to tree species and tree structure. The recurrence interval observed on the stem surface of Q. pubescens exceeds that of A. opalus by > 20 years in the lower part of the studied plot. Similarly, the recurrence interval map derived from A. opalus coppice stands, dominant at the stand scale, does not exhibit a clear spatial pattern. Differences between species may be explained by the bark

  11. Climate Change in the School Yard: Monitoring the Health of Acer Saccharum with A Maple Report Card

    Carlson, M.; Diller, A.; Rock, B. N.

    2012-12-01

    K-12 Teachers and students engage in authentic science and a research partnership with scientists in Maple Watch, a University of New Hampshire outreach program. Maple Watch is a hands-on, inquiry-based program in which students learn about climate change and air quality as well as many other environmental stress factors which may affect the health of sugar maple. The iconic New England tree is slated to lose 52% of its range in this century. Maple Watch builds on the 20-year record of Forest Watch, a K-12 program in which students and teachers have contributed annual research specimens and data to a UNH study of tropospheric ozone and its impact on white pine (Pinus strobus). Maple Watch students monitor sugar maples (Acer saccharum) year-round for signals of strain and disease. Students report the first run in sap season, bud burst and leaf development, and leaf senescence and fall. Across New England the timing of these phenologic events is changing with climate warming. Students assess maple health with simple measures of leaf development in May, leaf senescence in early fall and bud quality in late fall. Simple student arithmetic rankings of leaf and bud health correlate with chlorophyll content and spectral reflectance measures that students can analyze and compare with researchers at UNH. Grading their trees for each test on a one-two-three scale, students develop a Maple Report Card for each type of measurement, which presents an annual portrait of tree health. Year-by-year, schools across the sugar maple's 31 million acre range could monitor changes in tree health. The change over time in maple health can be graphed in parallel with the Goddard Space Institute's Common Sense Climate Index. Four teachers, listed as co-authors here, began a pilot study with Maple Watch in 2010, contributing sap samples and sharing curricular activities with UNH. Pilot Maple Watch schools already manage stands of sugar maples and make maple syrup and are assisting in training

  12. Gene Expressing and sRNA Sequencing Show That Gene Differentiation Associates with a Yellow Acer palmatum Mutant Leaf in Different Light Conditions

    Shu-Shun Li

    2015-01-01

    Full Text Available Acer palmatum Thunb., like other maples, is a widely ornamental-use small woody tree for leaf shapes and colors. Interestingly, we found a yellow-leaves mutant “Jingling Huangfeng” turned to green when grown in shade or low-density light condition. In order to study the potential mechanism, we performed high-throughput sequencing and obtained 1,082 DEGs in leaves grown in different light conditions that result in A. palmatum significant morphological and physiological changes. A total of 989 DEGs were annotated and clustered, of which many DEGs were found associating with the photosynthesis activity and pigment synthesis. The expression of CHS and FDR gene was higher while the expression of FLS gene was lower in full-sunlight condition; this may cause more colorful substance like chalcone and anthocyanin that were produced in full-light condition, thus turning the foliage to yellow. Moreover, this is the first available miRNA collection which contains 67 miRNAs of A. palmatum, including 46 conserved miRNAs and 21 novel miRNAs. To get better understanding of which pathways these miRNAs involved, 102 Unigenes were found to be potential targets of them. These results will provide valuable genetic resources for further study on the molecular mechanisms of Acer palmatum leaf coloration.

  13. A first look at the ACER-SST dataset: Mapping the spatio-temporal variability of sea-surface temperatures in the last Glacial and the Holocene

    Rehfeld, Kira; Laepple, Thomas; Bassinot, Franck; Daniau, Anne-Laure; Desprat, Stéphanie; Kim, Jung-Hyun; Fernanda Sánchez-Goñi, Maria; Harrison, Sandy

    2016-04-01

    Climate in the last Glacial was characterized by abrupt and large-scale changes around cold Heinrich-Events and warm Dansgaard-Oeschger excursions in the Northern high latitudes. The global repercussions of these periods of rapid dynamics are, to date, unconstrained. Here, we present a first statistical analysis of the global multi-proxy ACER (Abrupt Climate Changes and Environmental Responses) sea surface temperature dataset, spanning the last 80 thousand years, to investigate the spatial footprints of glacial climate dynamics. In a first step we evaluate the spatial and temporal variability throughout the Glacial period, and contrast them with that during the Holocene. In a second step we investigate to which extent a temporal synchroneity of extreme events during the Glacial is detectable in the proxy records, and analyze the reversibility of Glacial dynamics.

  14. Role of the Gelatinous Layer (G-Layer) on the Origin of the Physical Properties of the Tension Wood of Acer sieboldianum

    Yamamoto, H; Arakawa, Y; Okuyama, T; Gril, J; Yamamoto, Hiroyuki; Abe, Kentaro; Arakawa, Yoshiharu; Okuyama, Takashi; Gril, Joseph

    2005-01-01

    The tension wood (TW) properties of a 70 year-old Acer sieboldianum Miq were analyzed by using the G-fiber model which was proposed in our previous paper. The roles of the G-layer on the origins of (1) a high large tensile growth stress, (2) a large longitudinal Young's modulus, and (3) a high longitudinal drying shrinkage in the tension wood xylem were discussed on the basis of the simulations using the G-fiber model. The results suggest that the G-layer generates a high tensile stress in the longitudinal direction during the xylem maturation; the longitudinal Young's modulus of the green G-layer becomes significantly higher than that of the lignified layer; furthermore, the G-layer tends to shrink extraordinarily higher than that of the lignified layer during the moisture desorption.

  15. Ecotoxicological effects evoked in hydrophytes by leachates of invasive Acer negundo and autochthonous Alnus glutinosa fallen off leaves during their microbial decomposition

    Throughout 90-day biodegradation under microaerobic conditions, invasive to Lithuania species boxelder maple (Acer negundo) leaves lost 1.5-fold more biomass than that of autochthonous black alder (Alnus glutinosa), releasing higher contents of Ntot, ammonium and generating higher BOD7. Boxelder maple leaf leachates were characterized by higher total bacterial numbers and colony numbers of heterotrophic and cellulose-decomposing bacteria than those of black alder. The higher toxicity of A. negundo aqueous extracts and leachates to charophyte cell (Nitellopsis obtusa), the inhabitant of clean lakes, were manifested at mortality and membrane depolarization levels, while the effect on H+-ATPase activity in membrane preparations from the same algae was stronger in case of A. glutinosa. Duckweed (Lemna minor), a bioindicator of eutrophic waters, was more sensitive to leaf leachates of A. glutinosa. Fallen leaves and leaf litter leachates from invasive and native species of trees, which enter water body, affect differently microbial biodestruction and aquatic vegetation in freshwater systems. - Highlights: ► We examined Acer negundo and Alnus glutinosa leaf extract effects on hydrophytes. ► Nitellopsis obtusa and Lemna minor responded differently to leaf litter leachates. ► 90-day biodegraded A. negundo leaves lost twofold more biomass than that of A. glutinosa. ► A. negundo leachates evoked higher mortality and cell depolarization of N. obtusa. ► Leachates affected H+-ATPase activity in algae membrane preparations. - Fallen leaves and leaf litter leachates from invasive and native species of trees, which enter waterbody can be environmental factor affecting differently microbial biodestruction and aquatic vegetation in freshwater systems, thus influencing ecological scenarios.

  16. Acerogenin A from Acer nikoense Maxim Prevents Oxidative Stress-Induced Neuronal Cell Death through Nrf2-Mediated Heme Oxygenase-1 Expression in Mouse Hippocampal HT22 Cell Line

    Dong-Sung Lee; Byung-Yoon Cha; Je-Tae Woo; Youn-Chul Kim; Jun-Hyeog Jang

    2015-01-01

    Oxidative cell damage contributes to neuronal degeneration in many central nervous system (CNS) diseases such as Parkinson’s disease, Alzheimer’s disease, and ischemia. Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a key role in the pathogenesis of neuronal diseases. The stem bark of Acer nikoense Maxim (Aceraceae) is indigenous to Japan; it has been used in folk medicine as a treatment of hepatic disorders and eye diseases. Acerogenin A, a natural compound is...

  17. Food-chain transfer of zinc from contaminated Urtica dioica and Acer pseudoplatanus L. to the aphids Microlophium carnosum and Drepanosiphum platanoidis Schrank

    This study examines the food-chain transfer of Zn from two plant species, Urtica dioica (stinging nettle) and Acer pseudoplatanus (sycamore maple), into their corresponding aphid species, Microlophium carnosum and Drepanosiphum platanoidis. The plants were grown in a hydroponic system using solutions with increasing concentrations of Zn from 0.02 to 41.9 mg Zn/l. Above-ground tissue concentrations in U. dioica and M. carnosum increased with increasing Zn exposure (p < 0.001). Zn concentrations in A. pseudoplatanus also increased with solution concentration from the control to the 9.8 mg Zn/l solution, above which concentrations remained constant. Zn concentrations in both D. platanoidis and the phloem tissue of A. pseudoplatanus were not affected by the Zn concentration in the watering solution. It appears that A. pseudoplatanus was able to limit Zn transport in the phloem, resulting in constant Zn exposure to the aphids. Zn concentrations in D. platanoidis were around three times those in M. carnosum. - Concentrations of Zn in two aphid species are dependant on species and exposure.

  18. The acropetal effects of indole-3-acetic acid in isolated shoot segments of Acer pseudoplatanus L. II. Possible regulation by a vectorial fieid of auxin waves

    Jacek A. Adamczyk

    2014-02-01

    Full Text Available The acropetal effects of auxin on elongation of axillary buds and on modulation of the wave-like pattern of basipetal efflux of natural auxin to agar from Acer pseudoplatanus L. shoots were studied. When synthetic IAA was applied to cut surfaces of one of two branches the elongation growth of buds situated on the opposite branch was retarded, suggesting regulation independent of the direct action of the molecules of the applied IAA. Oscillations in basipetal transport of natural auxin along the stem segments were observed corroborating the results of other authors using different tree species. Apical application of synthetic IAA for 1 hour to the lateral branch caused a phase shift of the wave-like pattern of basipetal efflux of natural auxin, when the stem segment above the treated branch was sectioned. The same effect was observed evoked by the laterally growing branch which is interpreted as an effect of natural auxin produced by the actively growing shoot. These modulations could be propagated acropetally at a rate excluding direct action of auxin molecules at the sites of measurement. The results seem to corroborate the hypothesis suggesting that auxin is involved in acropetal regulation of shoot apex growth through its effect upon modulation of the vectorial field which arises when the auxin-waves translocate in cambium.

  19. 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

    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.

  20. Effects of maple (Acer) plant part extracts on proliferation, apoptosis and cell cycle arrest of human tumorigenic and non-tumorigenic colon cells.

    González-Sarrías, Antonio; Li, Liya; Seeram, Navindra P

    2012-07-01

    Phenolic-enriched extracts of maple sap and syrup, obtained from the sugar and red maple species (Acer saccharum Marsh, A. rubrum L., respectively), are reported to show anticancer effects. Despite traditional medicinal uses of various other parts of these plants by Native Americans, they have not been investigated for anticancer activity. Here leaves, stems/twigs, barks and sapwoods of both maple species were evaluated for antiproliferative effects against human colon tumorigenic (HCT-116, HT-29, Caco-2) and non-tumorigenic (CCD-18Co) cells. Extracts were standardized to total phenolic and ginnalin-A (isolated in our laboratory) levels. Overall, the extracts inhibited the growth of the colon cancer more than normal cells (over two-fold), their activities increased with their ginnalin-A levels, with red > sugar maple extracts. The red maple leaf extract, which contained the highest ginnalin-A content, was the most active extract (IC₅₀  = 35 and 16 µg/mL for extract and ginnalin-A, respectively). The extracts were not cytotoxic nor did they induce apoptosis of the colon cancer cells. However, cell cycle analyses revealed that the antiproliferative effects of the extracts were mediated through cell cycle arrest in the S-phase. The results from the current study suggest that these maple plant part extracts may have potential anticolon cancer effects. PMID:22147441

  1. Food-chain transfer of zinc from contaminated Urtica dioica and Acer pseudoplatanus L. to the aphids Microlophium carnosum and Drepanosiphum platanoidis Schrank

    Sinnett, Danielle, E-mail: danielle.sinnett@forestry.gsi.gov.u [Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom); Hutchings, Tony R., E-mail: tony.hutchings@forestry.gsi.gov.u [Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Hodson, Mark E., E-mail: m.e.hodson@reading.ac.u [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom)

    2010-01-15

    This study examines the food-chain transfer of Zn from two plant species, Urtica dioica (stinging nettle) and Acer pseudoplatanus (sycamore maple), into their corresponding aphid species, Microlophium carnosum and Drepanosiphum platanoidis. The plants were grown in a hydroponic system using solutions with increasing concentrations of Zn from 0.02 to 41.9 mg Zn/l. Above-ground tissue concentrations in U. dioica and M. carnosum increased with increasing Zn exposure (p < 0.001). Zn concentrations in A. pseudoplatanus also increased with solution concentration from the control to the 9.8 mg Zn/l solution, above which concentrations remained constant. Zn concentrations in both D. platanoidis and the phloem tissue of A. pseudoplatanus were not affected by the Zn concentration in the watering solution. It appears that A. pseudoplatanus was able to limit Zn transport in the phloem, resulting in constant Zn exposure to the aphids. Zn concentrations in D. platanoidis were around three times those in M. carnosum. - Concentrations of Zn in two aphid species are dependant on species and exposure.

  2. Effects of elevated [CO2] and low soil moisture on the physiological responses of Mountain Maple (Acer spicatum L. seedlings to light.

    Gabriel Danyagri

    Full Text Available Global climate change is expected to affect how plants respond to their physical and biological environments. In this study, we examined the effects of elevated CO2 ([CO2] and low soil moisture on the physiological responses of mountain maple (Acer spicatum L. seedlings to light availability. The seedlings were grown at ambient (392 µmol mol(-1 and elevated (784 µmol mol(-1 [CO2], low and high soil moisture (M regimes, at high light (100% and low light (30% in the greenhouse for one growing season. We measured net photosynthesis (A, stomatal conductance (g s, instantaneous water use efficiency (IWUE, maximum rate of carboxylation (V cmax, rate of photosynthetic electron transport (J, triose phosphate utilization (TPU, leaf respiration (R d, light compensation point (LCP and mid-day shoot water potential (Ψx. A and g s did not show significant responses to light treatment in seedlings grown at low soil moisture treatment, but the high light significantly decreased the C i/C a in those seedlings. IWUE was significantly higher in the elevated compared with the ambient [CO2], and the effect was greater at high than the low light treatment. LCP did not respond to the soil moisture treatments when seedlings were grown in high light under both [CO2]. The low soil moisture significantly reduced Ψx but had no significant effect on the responses of other physiological traits to light or [CO2]. These results suggest that as the atmospheric [CO2] rises, the physiological performance of mountain maple seedlings in high light environments may be enhanced, particularly when soil moisture conditions are favourable.

  3. Fast-growing Acer rubrum differs from slow-growing Quercus alba in leaf, xylem and hydraulic trait coordination responses to simulated acid rain.

    Medeiros, Juliana S; Tomeo, Nicholas J; Hewins, Charlotte R; Rosenthal, David M

    2016-08-01

    We investigated the effects of historic soil chemistry changes associated with acid rain, i.e., reduced soil pH and a shift from nitrogen (N)- to phosphorus (P)-limitation, on the coordination of leaf water demand and xylem hydraulic supply traits in two co-occurring temperate tree species differing in growth rate. Using a full-factorial design (N × P × pH), we measured leaf nutrient content, water relations, leaf-level and canopy-level gas exchange, total biomass and allocation, as well as stem xylem anatomy and hydraulic function for greenhouse-grown saplings of fast-growing Acer rubrum (L.) and slow-growing Quercus alba (L.). We used principle component analysis to characterize trait coordination. We found that N-limitation, but not P-limitation, had a significant impact on plant water relations and hydraulic coordination of both species. Fast-growing A. rubrum made hydraulic adjustments in response to N-limitation, but trait coordination was variable within treatments and did not fully compensate for changing allocation across N-availability. For slow-growing Q. alba, N-limitation engendered more strict coordination of leaf and xylem traits, resulting in similar leaf water content and hydraulic function across all treatments. Finally, low pH reduced the propensity of both species to adjust leaf water relations and xylem anatomical traits in response to nutrient manipulations. Our data suggest that a shift from N- to P-limitation has had a negative impact on the water relations and hydraulic function of A. rubrum to a greater extent than for Q. alba We suggest that current expansion of A. rubrum populations could be tempered by acidic N-deposition, which may restrict it to more mesic microsites. The disruption of hydraulic acclimation and coordination at low pH is emphasized as an interesting area of future study. PMID:27231270

  4. Chemical and physical properties of two-year short-rotation deciduous species. [Olea sp. , Populus deltoides, Platanus sp. , Alnus glutinosa, Paulownia tomentosa, Robina pseudoacacia, Acer saccharinum

    Lee, C.S

    1982-01-01

    The following seven broadleaved species were tested: autumn olive (Olea sp.) eastern cottonwood (Populus deltoides), sycamore (Platanus species), black alder (Alnus glutinosa), royal paulownia (Paulownia tomentosa), black locust (Robina pseudoacacia) and silver maple (Acer saccharinum). The species and portions both significantly affected the chemical and the physical findings of the juvenile wood. The ages, which were tested in factorial combination with the species, also showed a significant effect on both the chemical and the physical properties of wood. All of the results indicated that both chemical and physical properties did vary with species, among the portions of the wood, and according to the ages of the wood. From the portion standpoint, the bark had higher gross heat content, sulphur content, ash content and lignin content, and it was also higher in all three kinds of extractives contents. The wood portion was found to be rich in holocellulose, alpha-cellulose and pentosan. In considering the chemical and physical properties of juvenile wood among the species, eastern cottonwood was found to have the highest value for ash content and all of the three kinds of extractives content. Paulownia had the highest value for sulphur content. Black locust had highest gross heat content, holocellulose and alpha-cellulose contents. Silver maple had highest lignin content. Results from this study showed that these seven juvenile hardwood species can produce high biomass yields of fibre and energy when grown under intensive care in central and southern Illinois sites. The best species of these seven tested woods seem to be black locust, which could also serve as a raw material for the pulp and paper industry, as well as for a fuel for energy generation. However, further economic and energy efficiency analyses are needed before judging the feasibility of these short-rotation juvenile hardwood species.

  5. Seasonal changes in contents of phenolic compounds and sugar in Rhus, Euonymus and Acer leaves with special reference to anthocyanin formation in autumn

    The seasonal changes in the contents of sugar and phenolic compounds in the leaves of Rhus, Euonymus and two Acer species were examined in order to obtain information on the metabolic process inducing the autumn reddening. The incorporation of radioactivity of glucose-(U-14C) into anthocyanin was also examined. As a result of a preliminary test, the compositions of sugar and phenolic compounds were not altered by the drying treatment, therefore dried material was used. Dried leaves (ca. 2 g) were subject to the extraction with 80% methanol (3 ml, 3 hr) under refluxing. The extraction was repeated twice. Combined extracts (ca. 90 ml) were concentrated to ca. 20 ml at 35 deg C under reduced pressure. The concentrate was repeatedly washed with n-hexane and evaporated to remove the n-hexane. The resulting solution was made up to 30 ml with water, and used for the quantitative analysis. The solutions were fractionated in order to estimate total phenol and flavanol contents. Sugars were extracted from dry leaves (ca. 2 g) by boiling 70% ethanol (20 ml) for 3 hours. D-glucose-(U-14C)(280 mCi/mM) and phenylalanine-(U-14C)(422 mCi/mM) were fed to the leaves. It was found that antho-cyanin (mainly cyanidin 3-monoglucoside) was produced in the autumnal leaves of all plants examined, and that the red pigment was steadily accumulated in their leaves during the autumn. The sugar accumulated in autumnal Rhus leaves may be rapidly consumed by the formation of phenolic compounds. (Iwakiri, K.)

  6. Physiological and foliar symptom response in the crowns of Prunus serotina, Fraxinus americana and Acer rubrum canopy trees to ambient ozone under forest conditions

    The crowns of five canopy dominant black cherry (Prunus serotina Ehrh.), five white ash (Fraxinus americana L.), and six red maple (Acer rubrum L.) trees on naturally differing environmental conditions were accessed with scaffold towers within a mixed hardwood forest stand in central Pennsylvania. Ambient ozone concentrations, meteorological parameters, leaf gas exchange and leaf water potential were measured at the sites during the growing seasons of 1998 and 1999. Visible ozone-induced foliar injury was assessed on leaves within the upper and lower crown branches of each tree. Ambient ozone exposures were sufficient to induce typical symptoms on cherry (0-5% total affected leaf area, LAA), whereas foliar injury was not observed on ash or maple. There was a positive correlation between increasing cumulative ozone uptake (U) and increasing percent of LAA for cherry grown under drier site conditions. The lower crown leaves of cherry showed more severe foliar injury than the upper crown leaves. No significant differences in predawn leaf water potential (ψL) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (gwv) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (Pn), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P wv and Pn demonstrate the strong influence of heterogeneous environmental conditions within forest canopies. - Within the heterogeneous environment of a mature forest, many factors in addition to soil moisture play a significant role in determining exposure/response relationships to ozone

  7. Desarrollo de matrices cerámicas y geopoliméricas como vías de inmovilización de polvos de acería

    Díaz Fernández, María del Carmen

    2016-01-01

    Este trabajo de Tesis Doctoral se enmarca en el ámbito de Economía Circular, ya que se lleva a cabo la práctica del concepto de Simbiosis Industrial, introducir un flujo residual como materia prima en otro ciclo productivo, con objeto de intentar dar solución al problema de contaminación que genera un residuo siderúrgico muy concreto como son los polvos de acería, cuya principal vía de gestión actualmente sigue siendo la deposición en vertedero controlado. Se va a estudiar la viabilidad de in...

  8. An Analysis of Effects of Grafting with Two Kinds of Scion of Acer negundo%金叶复叶槭两种接穗嫁接效果分析

    曾健

    2014-01-01

    A grafting trial was made with the double bud and four bud of Acer negundo as scions. It was found that with the double bud scion the survival rate was higher than that with the four bud scion, the growth was greater and the production cost was saved greatly.%以金叶复叶槭双芽和四芽做接穗进行嫁接试验,发现采用双芽接穗比四芽接穗嫁接成活率高,生长量大,而且能极大地节约生产成本。

  9. Isolation and Identification of an Endophytic Fungus Producing Gallic Acid from Acer ginnala%一株产没食子酸的茶条槭内生真菌的分离鉴定

    齐凤慧; 詹亚光; 景天忠

    2009-01-01

    从采自黑龙江省植物园的茶条槭(Acer ginnala Maxim.)的种子和枝条中分离内生真菌,用形态学和分子生物学方法鉴定分离菌株,应用高效液相色谱法检测内生真菌中没食子酸含量.结果从分离得到的链格孢属(Altemaria)菌株中选出没食子酸含量为9.52 mg/g的高产菌株CP11.

  10. Adaptación y validación en Colombia del addenbrooke’s cognitive examination-revisado (ACE-R) en pacientes con deterioro cognoscitivo leve y demencia

    Ospina García, Natalia Alexandra

    2015-01-01

    Introducción: El Addenbrooke‘s Cognitive Examination - revisado (ACE-R) es una prueba multidominio que tiene alta sensibilidad y especificidad para la detección de deterioro cognoscitivo leve y demencia en estadios tempranos. Es ampliamente usada en el mundo. En Colombia existen pocas pruebas para la detección temprana de demencia. Se requieren instrumentos validados con el rigor metodológico para conservar las propiedades del instrumento original y que se adapten a las particularidades de...

  11. Estructures bainítiques en acers HSLA de baix contingut en carboni: Influència del contingut en microaleants i del tractament tèrmic sobre l'estructura i propietats

    Illescas Fernández, Silvia

    2007-01-01

    En la present tesi doctoral s'ha portat a terme l'estudi d'estructures bainítiques i les seves propietats en dos acers HSLA de baix contingut en carboni de composicions molt semblants a excepció del contingut en elements de microaleants (Vanadi, Niobi i Titani), de manera que s'ha pretès establir la influència de cada un d'aquests elements sobre les estructures i propietats mecàniques observades.Previament a l'obtenció d'estructures bainítiques, s'han determinat les condicions òptimes d'auste...

  12. DNA Barcoding of Acer palmatum (Aceraceae)%鸡爪槭种下分类群的DNA条形码筛选

    高健; 孟婉姮; 杜芳; 李俊清

    2015-01-01

    槭属鸡爪槭(Acer palmatum Thunb.)是北温带广泛分布的一类园艺观赏树种,由于频繁的种内杂交渐渗导致其种下分类群的形态性状特征趋同,致使传统的形态学分类难以准确鉴定,新兴的DNA条形码技术为快速、准确的鉴定鸡爪槭种下分类群提供了新的思路.本研究采用5个叶绿体DNA片段(rpl16、psbA-trnH、trnL-trnF、rbcL、matK)和核基因组ITS片段,运用PWG-distance和Tree-Building两种方法对鸡爪槭的8个分类群共32个个体进行DNA条形码分析.结果显示,单个叶绿体基因组片段(分辨率为0%~25%)或核rDNAITS片段(12.5%)的分辨率较低,不同组合的叶绿体DNA片段(0%~62 5%)、叶绿体片段与核rDNA ITS片段(12.5%~50%)的分辨率则相对较高.其中,rpl16+psbA-trnH+tmL-trnF片段组合的分辨率最高(62.5%),较为符合DNA条形码快速、准确鉴定的要求,因此建议将其作为鸡爪槭种下分类群鉴定的DNA条形码.

  13. Chronic drought stress reduced but not protected Shantung maple (Acer truncatum Bunge) from adverse effects of ozone (O3) on growth and physiology in the suburb of Beijing, China

    A two-year experiment exposing Acer truncatum Bunge seedlings to elevated ozone (O3) concentrations above ambient air (AO) and drought stress (DS) was carried out using open-top chambers (OTCs) in a suburb of Beijing in north China in 2012–2013. The results suggested that AO and DS had both significantly reduced leaf mass area (LMA), stomatal conductance (Gs), light saturated photosynthetic rate (Asat) as well as above and below ground biomass at the end of the experiment. It appeared that while drought stress mitigated the expression of foliar injury, LMA, leaf photosynthetic pigments, height growth and basal diameter, due to limited carbon fixation, the O3 – induced reductions in Asat, Gs and total biomass were enhanced 23.7%. 15.5% and 8.1% respectively. These data suggest that when the whole plant was considered that drought under the conditions of this experiment did not protect the Shantung maple seedlings from the effects of O3. - Highlights: • The response of Acer truncatum Bunge to drought and ozone was investigated. • Drought could mitigate the foliage injury and leaf photosynthetic pigments. • The O3-induced reductions in Asat, Gs and total biomass were enhanced by drought. - Drought didn't protect Shantung maple from O3 effects but rather cause more reductions in biomass

  14. The Monte Carlo event generator AcerMC versions 2.0 to 3.8 with interfaces to PYTHIA 6.4, HERWIG 6.5 and ARIADNE 4.1

    Kersevan, Borut Paul; Richter-Waş, Elzbieta

    2013-03-01

    The AcerMC Monte Carlo generator is dedicated to the generation of Standard Model background processes which were recognised as critical for the searches at LHC, and generation of which was either unavailable or not straightforward so far. The program itself provides a library of the massive matrix elements (coded by MADGRAPH) and native phase space modules for generation of a set of selected processes. The hard process event can be completed by the initial and the final state radiation, hadronisation and decays through the existing interface with either PYTHIA, HERWIG or ARIADNE event generators and (optionally) TAUOLA and PHOTOS. Interfaces to all these packages are provided in the distribution version. The phase-space generation is based on the multi-channel self-optimising approach using the modified Kajantie-Byckling formalism for phase space construction and further smoothing of the phase space was obtained by using a modified ac-VEGAS algorithm. An additional improvement in the recent versions is the inclusion of the consistent prescription for matching the matrix element calculations with parton showering for a select list of processes. Catalogue identifier: ADQQ_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADQQ_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 3853309 No. of bytes in distributed program, including test data, etc.: 68045728 Distribution format: tar.gz Programming language: FORTRAN 77 with popular extensions (g77, gfortran). Computer: All running Linux. Operating system: Linux. Classification: 11.2, 11.6. External routines: CERNLIB (http://cernlib.web.cern.ch/cernlib/), LHAPDF (http://lhapdf.hepforge.org/) Catalogue identifier of previous version: ADQQ_v1_0 Journal reference of previous version: Comput. Phys. Comm. 149(2003)142 Does

  15. 不同光强对元宝枫叶生物活性物质含量的影响%Influence of light intensities on the contents of bioactivity substances in the leaves of Acer truncatum

    樊艳平; 姚延梼

    2011-01-01

    元宝枫叶含有黄酮、绿原酸、SOD活性酶、丙二醛和Vc等多种生物活性物质.以2年生元宝枫苗为试材,对其进行不同光强处理,测定叶内黄酮、绿原酸、SOD酶、丙二醛和Vc的含量.结果表明,不同光强处理对元宝枫叶内生物活性物质含量的影响十分显著,其中以60%自然光处理下的元宝枫叶黄酮含量最高,全自然光处理下绿原酸和Vc含量最高,而45%自然光处理下的元宝枫叶SOD酶活性和丙二醛含量最高.综合来看,不同的光强处理对元宝枫叶内生物活性物质含量的积累是不同的.%The contents of bioactive substances including flavonoids, chlorogenic acids, SOD enzyme, MDA, and Vc in the leaves of two-year-old Acer truncatum seedlings were studied under different light intensities. The results showed that the different light intensities had obvious influences on the contents of bioactive substances in the leaves of A. truncatum seedlings. The content of flavonoids in the leaves treated with 60% light intensity was the highest and the contents of chlorogenic acids and Vc in the leaves treated with 100% light intensity were the highest. While SOD enzye activity and MDA content in the leaves were the highest under 45% light intensity. Comprehensively, the accumulations of bioactive substances in the leaves of A. truncatum seedlings varied with the light intensities and the bioactive components.

  16. Study on the structure and dynamic population of renewed Acer mono seedlings in secondary poplar-birth forest in the mountainous regions of Northern Hebei%冀北山地杨桦次生林五角枫更新幼苗种群结构与动态研究

    王广海; 于树峰; 刘春利; 金春生; 任佳美

    2013-01-01

    对冀北山地杨桦次生林五角枫更新幼苗种群结构进行了研究,分析了五角枫幼苗种群的径级结构、高度结构、时间序列预测以及点格局。结果表明,五角枫更新苗总株数为1094株/hm2,五角枫更新苗径级主要集中在0.5~2cm之间,占总株数的73.31%。其高度主要集中在0.5~2.5m,占总株数的81.81%。Ⅱ径级、Ⅳ径级和Ⅵ径级后,五角枫更新苗株数分别下降了5%,40%和83%,表明五角枫更新幼苗小径阶种群仍然保持较多的个体,五角枫种群保持相对的稳定性。五角枫更新幼苗在0~13 m范围内呈聚集分布,在14~16 m范围内呈随机分布,在17~25 m范围内呈均匀分布。适当间伐五角枫更新幼苗对杨桦次生林结构优化和功能发挥具有重要意义。%The structure population of renewed Acer mono seedlings in secondary poplar-birth forest in Northern Hebei mountain was researched systematically with its diameter class , height class ,time sequence ,and point pattern analyzed .The results showed that the total plant number of renewed Acer mono seedling was 1 094/hm2 ,and its diameter class between 0 .5 cm and 2 cm ,accounted for 73 .31% of the total number of trees ,with its height class between 0 .5 cm and 2 .5 cm accounting for 81 .81% of the total number of trees .Time se-quence prediction model for renewed Acer mono seedling populations after Ⅱ ,Ⅳ and Ⅵ di-ameter calss indicated 5% ,40% and 83% decline in regeneration seedling number respective-ly .Small population remains larger number ,which showed Acer mono seedlings were re-newed stably .Renewed Acer mono seedlings in the range of 0~13 m was in an aggregated distribution ,with its random distribution in 14~16 m ,and its uniform distribution in 17~25 m .Therefore ,it is of great significance to proper intermediate cutting the renewed Acer mono seedlings for the optimization of its structure and function .

  17. Population structure and dynamics of the endemic plant Acer guizhouense in Guizhou Province%贵州特有植物贵州槭的种群结构及动态研究

    刘海燕; 杨乃坤; 邹天才; 黄丽华; 汪建文

    2016-01-01

    Acer guizhouense is a kind of evergreen broad-leaved tree with scientific and economic value, which only dis-tributed at 770-1 000 m in evergreen and deciduous broad-leaved mixed forest with mountain barrier in Xinzhou Town of Huangping County in Guizhou Province. So, it has significant value to explore conservation biology of endemic plants by studying its population structure and dynamic change. We took general survey in suspected distribution area, set up plots in dense area for full investigation, and analyzed the population structure and quantity dynamics pattern. The results were as follows:(1) The natural distribution region of A. guizhouense was very narrow, covered about 0.3 km2 in Leiping with a total of 2 600 trees. The dense area was 0.03 km2 , average population density 78 800 trees/km2 . The sporadic distribu-tion was 0.27 km2 , average population density≤1 500 trees/km2 . The species occasionally distributed in about 0.05 km2 Feiyunya of Dongpo Village. But there was no natural distribution between Leiping and Dongpo. According to the SAFE index and evaluation standard of IUCN, A. guizhouense was EN species. (2) The structure of A. guizhouense population was increasing and the proportion of young tree in population was 63.23%. The size of population density was young trees>middle-aged trees>adult trees. There were 2 peaks in theⅠand Ⅸ age-classes on the mortality rate curve and disap-pearance rate curve respectively, then there were 2 troughs inⅢ-ⅧandⅩ-Ⅺage-classes. So the survival curve of pop-ulation was more in line with the characteristics of Deevey-Ⅲmodel. (3) The main reason of few population individuals of A. guizhouense was the plant death or loss caused by human deforestation and habitat destruction. It is a practical and effective reasonable protection measure to carry out artificial breeding and ex situ cultivation when we strengthen the in situ conservation.%贵州槭( Acer guizhouense)属常绿阔叶乔木,仅分布于

  18. Effects of Nitrogen Fertilization on Potato Leafhopper (Hemiptera: Cicadellidae) and Maple Spider Mite (Acari: Tetranychidae) on Nursery-Grown Maples.

    Prado, Julia; Quesada, Carlos; Gosney, Michael; Mickelbart, Michael V; Sadof, Clifford

    2015-06-01

    Although leaf nitrogen (N) has been shown to increase the suitability of hosts to herbivorous arthropods, the responses of these pests to N fertilization on susceptible and resistant host plants are not well characterized. This study determined how different rates of N fertilization affected injury caused by the potato leafhopper (Empoasca fabae Harris) and the abundance of maple spider mite (Oligonychus aceris (Shimer)) on 'Red Sunset' red maple (Acer rubrum) and 'Autumn Blaze' Freeman maple (Acer×freemanii) during two years in Indiana. N fertilization increased leaf N concentration in both maple cultivars, albeit to a lesser extent during the second year of the study. Overall, Red Sunset maples were more susceptible to E. fabae injury than Autumn Blaze, whereas Autumn Blaze maples supported higher populations of O. aceris. Differences in populations of O. aceris were attributed to differences between communities of stigmaeid and phytoseiid mites on each cultivar. Injury caused by E. fabae increased with N fertilization in a dose-dependent manner in both cultivars. Although N fertilization increased the abundance of O. aceris on both maple cultivars, there was no difference between the 20 and 40 g rates. We suggest the capacity of N fertilization to increase O. aceris on maples could be limited at higher trophic levels by the community of predatory mites. PMID:26470249

  19. 元宝枫、雪松挥发物释放的昼夜节律%Diurnal Rhythm of Emission of Volatile Compounds Emission from Acer truncatum and Cedrus deodara

    宋秀华; 李传荣; 许景伟; 胡丁猛; 王超

    2015-01-01

    Objective]Most volatiles released from green plants have significant physiological activity, such as regulating plant growth,enhancing its resistance,inhibiting the growth of air microorganisms,and also producing different influences on human physiology and psychology. Acer truncatum and Cedrus deodara are common urban greening tree species,typical representative of hardwoods and conifers in Northern China. In this paper,the diurnal rhythm of volatiles released from the two species was detected and the environmental impact of the volatiles was investigated,to provide scientific reference for the urban green space recreation construction by proper tree species configuration and create the green environment more conducive to human health. [Method]The sunward leaves and branches of perennial and heathy A. truncatum and C. deodara were collected,and the volatiles were measured by using the SPME-GC-MS technique every 3 hours from 8:00 to 5:00 in the mid July. At the same time the temperature and humidity of the environment were measured. The SPSS software was used to analyze the data. [Result]1) The C6 and C8 esters,alcohols,aldehydes and terpenes were the dominant components released from A. truncatum. The 3-hexenyl acetate,hexyl acetate,3-hexen-1-ol, 3-hexenal,and β-caryophyllene accounted for 70% of the total volatiles,which made leaves give up the green leaf fragrance. Different compounds had different release patterns. The C8 esters,a major volatile,had the releasing peak at 14:00 ,and the lowest releasing point at 5:00 . The C15 sesquiterpenes appeared two peaks and two valleys of the releases,the peaks were at 17:00 and 5:00,and the valleys were at 8:00 and 23:00,respectively. The correlation analysis showed that there was positive correlation between 3-hexen-1-ol and 3-hexenal,and negative correlations between 3-hexenyl acetate with 3-hexen-1-ol and 3-hexenal. No significant correlations were found between other compounds. 2 ) The volatiles of C. deodara leaves

  20. Morphological characters of the flowers and the structure of the nectaries of Acer platanoides L.

    Elżbieta Weryszko-Chmielewska

    2012-12-01

    Full Text Available The micromorphology of the nectaries and of other elements of the flower was examined by scanning electron microscopy (SEM. The anatomy of the nectaries was determined using light microscopy (LM. The inflorescences of A. platanoides comprise flowers included in two categories: functionally male and female. Nectaries of similar structure are found in both types of these flowers. The nectary gland located on the surface of the receptacle belongs to interstaminal nectaries. It has the form of a fleshy ring situated between the petals and the pistil. The bases of the staminal filaments are located in the depressions of the nectary. The outer diameter of the nectary reaches ca. 5 mm, while the thickness of this gland's tissues is 400-700 μm. In the epidermis of the nectary gland, there are numerous, evenly distributed stomata through which nectar release occurs. The stomata function asynchronously. In some stomata, we could observe nectar drops flowing out and a layer of this secretion around the stomata. The secretory parenchyma of the nectary is composed of several layers of thick-walled cells, whereas the ends of the vascular bundles with xylem and phloem elements are situated in the subglandular parenchyma. Chloroplasts are found both in the epidermal cells and in the glandular parenchyma cells and photosynthesis can take place in them due to the nectary's good exposure to light. The presence of starch grains was found in the chloroplasts; they can be energy material for nectar production.

  1. ACER: A Framework on the Use of Mathematics in Upper-division Physics

    Caballero, Marcos D; Pepper, Rachel E; Pollock, Steven J

    2012-01-01

    At the University of Colorado Boulder, as part of our broader efforts to transform middle- and upper-division physics courses, we research students' difficulties with particular concepts, methods, and tools in classical mechanics, electromagnetism, and quantum mechanics. Unsurprisingly, a number of difficulties are related to students' use of mathematical tools (e.g., approximation methods). Previous work has documented a number of challenges that students must overcome to use mathematical tools fluently in introductory physics (e.g., mapping meaning onto mathematical symbols). We have developed a theoretical framework to facilitate connecting students' difficulties to challenges with specific mathematical and physical concepts. In this paper, we motivate the need for this framework and demonstrate its utility for both researchers and course instructors by applying it to frame results from interview data on students' use of Taylor approximations.

  2. PISA 2003 Australia: ICT Use Familiarity at School and Home. ACER Research Monograph Number 62

    Thomson, Sue; De Bortoli, Lisa

    2007-01-01

    As countries continue to invest in information and communication technologies (ICT) and they become even more common in the workplace, there is an increasing demand for schools to produce technologically literate students. This report presents results from the "Programme for International Student Assessment" (PISA) 2003, and examines how extensive…

  3. 有小有大:Acer Aspire One D250 SAMSUNG R720

    2009-01-01

    对于上网本来说.除了最近被炒得火热的Windows75统.貌似没有什么可宣传的噱头了.Acer这次采用Android系统来实现双系统.将启动时间大大缩短.并配合3G模块提供了更多的应用模式,可谓是一举多得的做法。对于SAMSUNGR720来说,我个人的确想在家摆放一台,相信和我有同样想法的人并不少.如果都是相对固定使用的话.为什么不找个大屏幕产品提升自己的使用感受呢?

  4. ACER: An Analytic Framework for Students' Use of Mathematics in Upper-Division Physics

    Wilcox, Bethany R; Rehn, Daniel A; Pollock, Steven J

    2013-01-01

    Many students in upper-division physics courses struggle with the mathematically sophisticated tools and techniques that are required for advanced physics content. We have developed an analytical framework to assist instructors and researchers in characterizing students' difficulties with specific mathematical tools when solving the long and complex problems that are characteristic of upper-division. In this paper, we present this framework, including its motivation and development. We also describe an application of the framework to investigations of student difficulties with direct integration in electricity and magnetism (i.e., Coulomb's Law) and approximation methods in classical mechanics (i.e., Taylor series). These investigations provide examples of the types of difficulties encountered by advanced physics students, as well as the utility of the framework for both researchers and instructors.

  5. Do interspecific differences in sapling growth traits contribute to the co-dominance of Acer saccharum and Fagus grandifolia?

    K. Takahashi; Lechowicz, MJ

    2008-01-01

    This is a pre-copy-editing, author-produced PDF of an article accepted for publication in ANNALS OF BOTANY following peer review.The definitive publisher-authenticated version ANNALS OF BOTANY 101(1):103-109,2008 is available online at:http://aob.oxfordjournals.org/cgi/content/abstract/101/1/103.

  6. Responses of secondary chemicals in sugar maple (Acer saccharum) seedlings to UV-B, springtime warming and nitrogen additions

    Sager, E.P.S.; Hutchinson, T.C. [Trent Univ., Peterborough, ON (Canada). Environmental Studies

    2006-10-15

    Elevated UV-B radiation due to climatic change and ozone depletion may represent a significant springtime environmental stressor to germinating seedlings in temperate forest regions. This study aimed to determine the effects of UV-B, nitrogen (N) fertilization and climate warming on the concentrations of base cations and secondary metabolites in the foliage of sugar maple seedlings growing in acid or alkaline soils. The influence of measured flavonoids and phenolics on herbivore activity was examined, as well as the relationship between foliar concentrations of calcium (Ca); manganese (Mn); and N and the production of phenolic and flavonoid compounds. Experimental plots were established in mature hardwood forests in alkaline and acid soil locations in Bobcaygeon and Haliburton, Ontario. Pentagonal open-top chambers were used to lengthen the growing season and simulate an earlier spring. Ammonium nitrate was applied at a rate comparable with an additional deposition of 5 g N per m per year. Fertilizer was applied on 3 separate occasions. Ambient UV-B radiation was screened out with Mylar D polyester film. Sites, treatments and time of sampling had complex effects on foliar elemental chemistry, production of secondary compounds and herbivory. Foliar concentrations of individual phenols were higher in seedlings in the UV-B exclusion treatments. At both sites, removal of ambient UV-B led to increases in flavonoids and chlorogenic acid, and reduced herbivore activity. At Haliburton, ammonium nitrate fertilization led to further increases in foliar Mn. Nitrogen additions led to decreases in the concentrations of some flavonoids at both sites. It was concluded that the composition of the forest soil governs the response of seedlings when they are exposed to abiotic stressors. 63 refs., 5 tabs., 8 figs.

  7. Effect of intensive planting density on tree growth, wood density and fiber properties of maple (Acer velutinum Boiss.)

    Naji HR; Nia MF; Kiaei M; Abdul-Hamid H; Soltani M; Faghihi A

    2016-01-01

    Planting density is a major factor in determining tree growth and wood quality. Although the effect of low planting density on the variation of tree and wood characteristics has been already reported, the effect of intensive initial densities in plantations has not been fully assessed yet. In this study, the effect of intensive planting densities on tree growth, wood density and fiber cell properties was investigated in the context of the development of densely-stocked maple plantations for w...

  8. Evaluación de lombricompuestos como sustrato de crecimiento de Acer Negundo l. en Río Turbio

    Estefanía Ayelen Cosio

    2014-06-01

    Full Text Available Con el fin de buscar una alternativa de uso a la deposición final de residuosbiodegradables (RB se procesaron las corrientes más significativas de RB para Río Turbio mediante el compostaje y vermicompostaje de los mismos; con el objetivo dedeterminar la factibilidad de uso de estos lombricompuestos como sustrato de crecimiento de Acernegundo L. Para esto se realizó un ensayo en invernadero con un diseño completamente aleatorizado donde se evaluaron los siguientes sustratos de crecimiento: 100 % lombricompuesto de conejo, 100 % lombricompuesto de RSUB, 50% lombricompuesto de conejo y 50% de turba, 50% lombricompuesto RSUB y 50% turba y 100% turba. Para estimar la factibilidad del uso de los lombricompuestos, en elmes de abril se tomaron datos sobre alturay diámetro de cuello de los plantines y número de plantas logradas por tratamiento. Se registraron diferencias significativas en las alturas de plantines para cada tratamiento. Los plantines de mayor tamaño se produjeron en las bandejas de los sustratos formados por 100 % turba, 100% lombricompuesto deconejo, 50% lombricompuesto de conejo y 50% turba, seguidos por 50%lombricompuesto RSUB y 50% turba, siendo los de menor tamaño los obtenidos mediante 100%lombricompuesto de RSUB. La calidad de los plantines obtenidos a partir de sustratos de crecimiento constituidos por lombricompuesto de conejo y turba son comparables, no así los obtenidos a partir de sustratos con lombricompuestos de RSUB. Sin embargo ypese aque se obtuvo un menor rendimiento con el sustrato de RSUB, su uso resultó factible para los fines perseguidos, teniendo en cuenta además, que su utilización presenta ventajas ambientales para Río Turbio.

  9. Simulated changes in biogenic VOC emissions and ozone formation from habitat expansion of Acer Rubrum (red maple)

    A new vegetation trend is emerging in northeastern forests of the United States, characterized by an expansion of red maple at the expense of oak. This has changed emissions of biogenic volatile organic compounds (BVOCs), primarily isoprene and monoterpenes. Oaks strongly emit isoprene while red maple emits a negligible amount. This species shift may impact nearby urban centers because the interaction of isoprene with anthropogenic nitrogen oxides can lead to tropospheric ozone formation and monoterpenes can lead to the formation of particulate matter. In this study the Global Biosphere Emissions and Interactions System was used to estimate the spatial changes in BVOC emission fluxes resulting from a shift in forest composition between oak and maple. A 70% reduction in isoprene emissions occurred when oak was replaced with maple. Ozone simulations with a chemical box model at two rural and two urban sites showed modest reductions in ozone concentrations of up to 5–6 ppb resulting from a transition from oak to red maple, thus suggesting that the observed change in forest composition may benefit urban air quality. This study illustrates the importance of monitoring and representing changes in forest composition and the impacts to human health indirectly through changes in BVOCs. (paper)

  10. Selectivity mechanism of Anoplophora glabripennis on four different species of maples

    2008-01-01

    Anoplophora glabripennis (Motsch.) is a wood-boring beetle that is native to China. For a long time, it caused great losses in the economy and ecology of northwest China. Attractants are often used to control insects. The volatiles emitted from the host plant play an important role for insects in finding their target. To explore the mechanism of selec-tivity to different host plants, the response of Anoplophora glabripennis to four different host plants was investigated, which included Acer negundo L., Acer mono Maxim., Acer truncatum Bunge. and Acer platanoides L., and the com-pounds in the profiles of volatiles were identified from these species. The olfactory responses ofAnoplophora glabripennis to the odors of different plants showed preference for certain host plants: Acer negundo, Acer mono and Acer truncatum. The attraction ofAcer negundo and Acer mono was signifi-cantly different (pAcer mono Maxim.>Acer truncatum Bunge.>Acer platanoides L.. 1-penten-3-ol, ocimene and trans-Germanylacetone were repellent to Anoplophora glabripennis. 1-penten-3-ol and trans-gerranylacetone were identified in Acer platanoides, and Ocimene was the most attractive to Anoplophora glabripennis among these species. The extent of feeding damage caused by Anoplophora glabripennis differed among four species. The sequences was Acer negundo > Acer mono > Acer truncatum > Acer platanoides. The epidermal hairs of the four host plants revealed that the extent of damage was related to the physical characteristics of the host plants.

  11. Disease symptoms and their frequency of occurrence in sycamores (Acer pseudoplatanus L. in the Rymanów Forest Unit stands

    Tadeusz Kowalski

    2012-12-01

    Full Text Available Field studies were conducted in the years 2003 - 2005 in the Rymanów Forest Unit in 13 stands aged between 40 to 100 years, which had 10% - 60% of the sycamore in their species composition. They grew on a mountain forest site (12 stands and mountain riparian forest (1 stand. In each of them 100 trees were examined, growing next to each other in the central part of the stands. The disease symptoms, on trunks and in the crown area of each tree, and their intensity were determined according to the predefined symptomatic - developmental code. More than 80 fragments of wood and bark were collected from trunks of living and dead trees with local cankers and bark peeling off exposing wood. From the samples, 798 isolations were made on 2% malt - agar medium. The examined sycamores in the Rymanów Forest Unit showed a large variation in the disease symptoms and their occurrence frequency. Among 1300 analyzed trees, only 13.7% did not show external, macroscopic disease symptoms. There was a relatively large share of dead trees (15.0%, which in individual stands ranged 4.0 - 32.0%. The most frequent symptoms in crowns were as follows: top dying (6.3% trees, entire branch dying (16.2% or only their tops (9.6%, crown thinning (19.4%, leaf atrophy (10.8% and leaf discoloration (11.6%. On sycamores trunks, the following symptoms were found: plate-like and strip-like necrosis of bark that was breaking, falling off and exposing wood (8.6% trees, local bark cankers (14.7%, among which healed ones dominated (10.3%, bark cracks (14.3% and tree cancer symptoms (3.8%. Bark necrosis and wood exposure formed 1.5 times more frequently on the northern and western side than on the southern and eastern side, bark cracks appeared most frequently on the southern trunk side. On the cross sections of sycamore trunks, the following symptoms were found predominantly: T-shaped discolorations which appeared in the place of local healed cankers, dead wood regions in the places of local unhealed cankers and widespread bark cankers, sometimes taking the form of a sector reaching the part near the pith, and greyish - green or greenish - brown wood discolorations in the form of numerous stains, especially in the trunk periphery part. On the trunks of 184 (14.2% sycamores, perithecia of Nectria coccinea were present. They formed in the area of cankers on bark and exposed wood alike. Fruiting bodies of Nectria cinnabarina, Eutypa acharii, Melanomma pulvis-pyrius, conidiomata of Cytospora ambiens, Aposphaeria cf. pulviscula and conidiomata of Stegonsporium pyriforme occurred sporadically. From wood, the following were isolated predominantly: Basidiomycetes sp. 1, Chalara sp. 1, Cadophora fastigiata, Nectria cinnabarina and Cytospora ambiens. Chalara sp.1, with its morphological features, best matched the anamorph of Ceratocystis coerulescens sensu lato.

  12. First year sugar maple (Acer saccharum, Marsh. ) seedling nutrition, vesicular-arbuscular mycorrhizal colonization, physiology, and growth along an acidic deposition gradient in Michigan

    McLaughlin, J.W.

    1992-01-01

    A field study was conducted to evaluate the use of foliar amino acid and root reducing sugar accumulations to separate acidic deposition from natural (i.e., soil phosphorus, mycorrhizae, and temperature) ecosystem stressors on first-year sugar maple seedling growth in three Michigan forests. Seedling growth was greatest at the sites exposed to highest levels of acidic deposition. However, sites receiving greatest acidic deposition rates also had high available soil phosphorus contents. No significant differences occurred, suggesting increased nitrogen loadings were not reflected in seedling tissue nitrogen. Seedling root or foliar calcium, magnesium, or potassium also were not significantly different, suggesting those elements were not growth limiting. Significant differences, however, occurred for seedling arginine and glutamine concentrations in foliage and reducing sugar concentrations in roots and were negatively correlated with seedling tissue phosphorus concentrations, suggesting phosphorus was limiting seedling growth at the low acidic deposition site. Vesicular-arbuscular mycorrhizal colonization of seedling roots was greater at the low acidic deposition site and positively correlated with seedling amino acid and reducing sugar accumulation but negatively correlated with sucrose concentrations in seedling roots, indicating that the fungal partner may have stimulated sucrose degradation to reducing sugars. Both air and soil temperatures were positively correlated with total sugar and sucrose concentrations in seedling roots. High levels of arginine, glutamine, and reducing sugars were negatively correlated with seedling growth indicating that seedlings at the low acidic deposition site were more stressed than seedlings at the sites receiving higher levels of pollutant loads. The results suggest differences in foliar arginine and glutamine and root reducing sugars in the forests in this study are likely due to natural rather than acidic deposition stress.

  13. Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA

    Momen, Bahram; Behling, Shawna J; Lawrence, Gregory B.; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor, which can impede seedling survival.

  14. Photosynthetic and Growth Response of Sugar Maple (Acer saccharum Marsh.) Mature Trees and Seedlings to Calcium, Magnesium, and Nitrogen Additions in the Catskill Mountains, NY, USA.

    Momen, Bahram; Behling, Shawna J; Lawrence, Greg B; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor, which can impede seedling survival. PMID:26291323

  15. Intracellular ice and cell survival in cryo-exposed embryonic axes of recalcitrant seeds of Acer saccharinum: an ultrastructural study of factors affecting cell and ice structures

    Cryogenic technologies are required to preserve embryonic axes of recalcitrant seeds. Formation of potentially lethal intracellular ice limits successful cryopreservation; thus, it is important to understand the relationships among cryo-exposure techniques, water content and survival. In this pap...

  16. THE SCREENING ACTIVITY PARTS OF ACER TRUNCATUM BUNGE.AND OTHER PLANTS OF THE SAME GENUS BY THE BRINE SHRIMP LETAITY BIOASSAY%采用BSLB(Brine Shrimp Letality Bioassay)法对元宝枫(Acer truncatum Bunge.)及同属植物活性部位的筛选

    魏希颖; 吕居娴; 李映丽; 贺浪冲

    2004-01-01

    本文通过BSLB法对元宝枫及同属植物不同部位的水提物进行了活性试验,得知:元宝枫的幼技、种皮的水提物具一定的生物致死活性;同属植物青榨槭叶和种子,秦岭槭、杈叶槭果翅的水提物也具一定的生物致死活性.本实验为元宝枫及同属植物进行进一步肿瘤细胞的体外培养试验及动物模型试验提供了科学依据.%By means of the brine shrimp lethality bioassay the authors study the watering abstracts activity of the A. truncatum Bunge. and the other plants of the same genus. The results indicate that the tender bark and seed skin of A. truncatum Bunge have the bioactivity. The leaves and seeds of A. dervidii Fr, the seed skin of A. robustum pax. have the same activity. The test offers some scientific basis for the further researches of anticancer experiments and animal model test outside the body of cell.

  17. Evaluation and comparison of size-density relationships for pure even-aged stands of ash (Fraxinus excelsior L.), beech (Fagus silvatica L.), oak (Quercus petraea Liebl.), and sycamore maple (Acer pseudoplatanus L.)

    Le Goff, Noël; Ottorini, Jean Marc; Ningre, Francois

    2011-01-01

    Size-density relationships define the maximum number of stems that even-aged stands of a given species can hold in relation to the mean size of trees. They are used to derive stand density measures and are useful tools used to control tree mortality. Size-density relationships were already available in France for beech and oak. The objective of this study was to extend these relations to younger development stages and test if specific relations are needed to be established for a set of specie...

  18. Deposition velocities to Sorbus aria, Acer campestre, Populus deltoides x trichocarpa 'Beaupre', Pinus nigra and x Cupressocyparis leylandii for coarse, fine and ultra-fine particles in the urban environment

    Freer-Smith, P.H.; Beckett, K.P.; Taylor, Gail

    2005-01-01

    Trees are effective in the capture of particles from urban air to the extent that they can significantly improve urban air quality. As a result of their aerodynamic properties conifers, with their smaller leaves and more complex shoot structures, have been shown to capture larger amounts of particle matter than broadleaved trees. This study focuses on the effects of particle size on the deposition velocity of particles (Vg) to five urban tree species (coniferous and broadleaved) measured at two field sites, one urban and polluted and a second more rural. The larger uptake to conifers is confirmed, and for broadleaves and conifers Vg values are shown to be greater for ultra-fine particles (Dp<1.0 {mu}m) than for fine and coarse particles. This is important since finer particles are more likely to be deposited deep in the alveoli of the human lung causing adverse health effects. The finer particle fraction is also shown to be transported further from the emission source; in this study a busy urban road. In further sets of data the aqueous soluble and insoluble fractions of the ultra-fines were separated, indicating that aqueous insoluble particles made up only a small proportion of the ultra-fines. Much of the ultra-fine fraction is present as aerosol. Chemical analysis of the aqueous soluble fractions of coarse, fine and ultra-fine particles showed the importance of nitrates, chloride and phosphates in all three size categories at the polluted and more rural location.

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

    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...

  20. Analysis of Bivariate Extreme Values

    Egeland Busuttil, Chris

    2015-01-01

    Results show that there is high agreement between the distribution of the bivariate ACER functions and the distribution of the copula models with ACER marginals for all time series. The distribution of the copula models with Gumbel marginals display great discrepancies to the distribution of the bivariate ACER functions. These disagreements are greatest for short time series, and decrease as the time series become longer.

  1. Australian Council for Educational Research. Fifty-first Annual Report, 1980-81.

    Australian Council for Educational Research, Hawthorn.

    The introduction to this annual report traces the history, activities, and growth of the Australian Council for Educational Research (ACER), and notes future challenges facing ACER. Abstracts are presented of seven papers which were delivered at the Invitational Conference on Societal Change held in August l980 at the University of Melbourne.…

  2. Chemosensory proteins of the eastern honeybee, Apis cerana: Identification, tissue distribution and olfactory related functional characterization.

    Li, Hong-Liang; Ni, Cui-Xia; Tan, Jing; Zhang, Lin-Ya; Hu, Fu-Liang

    2016-01-01

    Chemosensory proteins (CSPs), a class of small soluble proteins, are thought to be involved in insect chemoreceptive behavior. Here, six CSP genes, AcerCSP1-6 from Apis cerana, were cloned and characterized from worker bees' antennae. Results revealed that the AcerCSPs' amino acid sequences shared high similarity with the homologous genes of Apis mellifera, but low similarity with other insect species. Compared with corresponding CSPs of A. mellifera, AcerCSPs (1, 3, 4, and 6) exhibit quite similar gene expression profiling. On the contrary, AcerCSP2 showed a higher expression level in the forager antennae and legs than CSP2 of A. mellifera. Furthermore, AcerCSP5 was not specifically expressed in larvae, unlike CSP5 of A. mellifera. In a ligand-binding assay, AcerCSP1 and AcerCSP2, which exhibited the highest expression in antennae of A. cerana, had a stronger affinity with candidate floral chemicals and pheromones than AcerCSP4, the results of which was supported by docking analysis, suggesting that the relevance of them with A. cerana olfactory functions. Taken together, these results suggest that despite the quasi-similarity of protein sequences between A. cerana and A. mellifera, differences in tissue expression and functional characteristics between the two species still exist, indicating that homologous proteins potentially perform different tasks even in related species. PMID:26773657

  3. Aluminum solubility and mobility in relation to organic carbon in surface soils affected by six tree species of the northeastern United States

    Dijkstra, F.A.; Fitzhugh, R.D.

    2003-01-01

    We compared Al solubility and mobility in surface soils among six tree species (sugar maple [Acer saccharum], white ash [Fraxinus americana], red maple [Acer rubrum, L.], American beech [Fagus grandifolia, Ehrh.], red oak [Quercus rubra, L.], and hemlock [Tsuga canadensis, Carr.]) in a mixed hardwoo

  4. Measuring Learning Growth in a World of Universal Education. International Developments. Volume 5, Article 4

    Turner, Ross

    2015-01-01

    In 2013, staff at the Australian Council for Educational Research (ACER) Centre for Global Education Monitoring (GEM) identified the need to build measurement tools to monitor learning growth that could be used across different year levels and in different national contexts. One of those projects, under ACER's Monitoring Trends in Educational…

  5. Alkaline ceramidase 1 is essential for mammalian skin homeostasis and regulating whole-body energy expenditure.

    Liakath-Ali, Kifayathullah; Vancollie, Valerie E; Lelliott, Christopher J; Speak, Anneliese O; Lafont, David; Protheroe, Hayley J; Ingvorsen, Camilla; Galli, Antonella; Green, Angela; Gleeson, Diane; Ryder, Ed; Glover, Leanne; Vizcay-Barrena, Gema; Karp, Natasha A; Arends, Mark J; Brenn, Thomas; Spiegel, Sarah; Adams, David J; Watt, Fiona M; van der Weyden, Louise

    2016-07-01

    The epidermis is the outermost layer of skin that acts as a barrier to protect the body from the external environment and to control water and heat loss. This barrier function is established through the multistage differentiation of keratinocytes and the presence of bioactive sphingolipids such as ceramides, the levels of which are tightly regulated by a balance of ceramide synthase and ceramidase activities. Here we reveal the essential role of alkaline ceramidase 1 (Acer1) in the skin. Acer1-deficient (Acer1(-/-) ) mice showed elevated levels of ceramide in the skin, aberrant hair shaft cuticle formation and cyclic alopecia. We demonstrate that Acer1 is specifically expressed in differentiated interfollicular epidermis, infundibulum and sebaceous glands and consequently Acer1(-/-) mice have significant alterations in infundibulum and sebaceous gland architecture. Acer1(-/-) skin also shows perturbed hair follicle stem cell compartments. These alterations result in Acer1(-/-) mice showing increased transepidermal water loss and a hypermetabolism phenotype with associated reduction of fat content with age. We conclude that Acer1 is indispensable for mammalian skin homeostasis and whole-body energy homeostasis. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. PMID:27126290

  6. Addenbrooke’s Cognitive Examination and Individual Domain Cut-Off Scores for Discriminating between Different Cognitive Subtypes of Parkinson’s Disease

    Dagmar Berankova

    2015-01-01

    Full Text Available Objective. The main aim of this study was to verify the sensitivity and specificity of Addenbrooke’s Cognitive Examination-Revised (ACE-R in discriminating between Parkinson’s disease (PD with normal cognition (PD-NC and PD with mild cognitive impairment (PD-MCI and between PD-MCI and PD with dementia (PD-D. We also evaluated how ACE-R correlates with neuropsychological cognitive tests in PD. Methods. We examined three age-matched groups of PD patients diagnosed according to the Movement Disorder Society Task Force criteria: PD-NC, PD-MCI, and PD-D. ROC analysis was used to establish specific cut-off scores of ACE-R and its domains. Correlation analyses were performed between ACE-R and its subtests with relevant neuropsychological tests. Results. Statistically significant differences between groups were demonstrated in global ACE-R scores and subscores, except in the language domain. ACE-R cut-off score of 88.5 points discriminated best between PD-MCI and PD-NC (sensitivity 0.68, specificity 0.91; ACE-R of 82.5 points distinguished best between PD-MCI and PD-D (sensitivity 0.70, specificity 0.73. The verbal fluency domain of ACE-R demonstrated the best discrimination between PD-NC and PD-MCI (cut-off score 11.5; sensitivity 0.70, specificity 0.73 while the orientation/attention subscore was best between PD-MCI and PD-D (cut-off score 15.5; sensitivity 0.90, specificity 0.97. ACE-R scores except for ACE-R language correlated with specific cognitive tests of interest.

  7. Variation in root wood anatomy

    Cutler, D.F.

    1976-01-01

    Variability in the anatomy of root wood of selected specimens particularly Fraxinus excelsior L. and Acer pseudoplatanus L. in the Kew reference microscope slide collection is discussed in relation to generalised statements in the literature on root wood anatomy.

  8. Dioecy Impacts on Plant Water Fluxes in Riparian Ecosystems

    Hultine, K. R.; Bush, S. E.; West, A. G.; Ehleringer, J. R.

    2005-12-01

    Dioecious plants are frequently associated with different spatial distributions of the two sexes across resource gradients. Segregation between sexes might be expected to occur if the cost of reproduction is greater in females than in males. If so, females would be under stronger selection to increase rates of resource uptake. Acer negundo is a dioecious riparian tree species that show spatial segregation among sexes: females are typically more common along streamside (high resource) environments than males. The spatial segregation of the sexes leads to the hypothesis that male and female individuals have varying influence on ecohydrological processes. To address this, we measured sap flux, water relations and hydraulic architecture of mature streamside (less than 1 m from stream channel) male and female Acer negundo trees occurring near Salt Lake City, Utah, USA during the 2004 growing season. Despite similar predawn and midday leaf water potentials, sap flux density ( Js) was 40 percent higher in female trees than in male trees during the 2004 growing season (n = 42 days, F = 73.56, P genders showed a similar relationship between conducting sapwood area to stem diameter ratio suggesting that differences in Js scale to the whole tree level. Sap flux data from Acer negundo trees was compared to five other co-occurring riparian tree species. Female Acer negundo trees showed the highest Js among all species while Js in male Acer negundo trees was lower than all other species except one ( Acer grandidentatum). These data demonstrate that individual female Acer negundo trees have the capacity remove water at higher rates than males in high resource environments. The spatial segregation of the sexes along streamside environments may therefore have profound impacts on ecohydrological processes such as stream discharge, groundwater recharge, and nutrient cycling.

  9. Use of Addenbrooke’s cognitive examination-revised to evaluate the patients’ state in general medical practice

    Nikolai Nikolayevich Ivanets

    2012-01-01

    Full Text Available The differential diagnosis of cognitive impairments is of great importance in mental disorders detectable in general medical practice. Objective: to study whether Addenbrooke's Cognitive Examination — Revised (ACE-R may be used in these patients. Patients and methods. The study was conducted in two steps at somatic hospitals and city polyclinics. It enrolled 130patients (36 men and 94 women with anxiety-depression spectrum disorders (ADSD, mild cognitive disorders (MCD and a concurrence of these conditions. The authors used the following psychometric scales: the hospital anxiety and depression scale; the mini-mental state examination; the frontal assessment battery; ACE-R; ten words learning test. The psychometric characteristics of ACE-R and the possibilities of its use were estimated to detect MCD. The differences in the spectrum of cognitive impairments were analyzed in patients with different types of ADSD. Results. ACE-R is shown to be an effective neuropsychological tool for the primary diagnosis, detection, and evaluation of MCD in the general medical network. The results of ACE-R use indicate that the spectrum of cognitive impairments has substantial differences in patients with different types of non-psychotic disorders.

  10. Host Plants of Xylosandrus mutilatus in Mississippi

    Host range of Xylosandrus mutilatus (Blandford) in North America is reported here for the first time. Descriptive data such as number of attacks per host, size of stems at point of attacks, and height of attacks above ground are presented. Hosts observed in Mississippi were Acer rubrum L., Acer saccharum Marsh., Acer palmatum Thunb., Ostrya virginiana (Mill.) K. Koch., Cornus florida L., Fagus grandifolia Ehrh., Liquidamber styraciflua L., Carya spp., Liriodendron tulipifera L., Melia azedarach L., Pinus taeda L., Prunus serotina Ehrh., Prunus americana Marsh., Ulmus alata Michaux, and Vitus rotundifolia Michaux. Liquidamber styraciflua had significantly more successful attacks, significantly higher probability of attacks, and significantly higher number of adult beetles per host tree than did Carya spp., A. rubrum, and L. tulipifera. This information is relevant in determining the impact this exotic beetle may have in nurseries, urban areas, and other forestry systems where this beetle becomes established. (author)

  11. English in Hong Kong: Word Knowledge Skills of Science Undergraduates.

    Stone, Raymond

    1999-01-01

    Examines the English language standard of a group of Hong Kong science undergraduates using the ACER Word Knowledge Test Form F. Results show a significant difference in apparent English skill levels between Hong Kong, American, and Australian students.(Author/VWL)

  12. Tree species effects on calcium cycling: The role of calcium uptake in deep soils

    Dijkstra, F.A.; Smits, M.M.

    2002-01-01

    Soil acidity and calcium (Ca) availability in the surface soil differ substantially beneath sugar maple (Acer saccharum) and eastern hemlock (Tsuga canadensis) trees in a mixed forest in northwestern Connecticut. We determined the effect of pumping of Ca from deep soil (rooting zone below 20-cm mine

  13. A Review of the Empirical Evidence Identifying Effective Interventions and Teaching Practices for Students with Learning Difficulties in Years 4, 5 and 6. Literature Review

    Purdie, Nola; Ellis, Louise

    2005-01-01

    This review has been prepared by the Australian Council for Educational research (ACER) under an Agreement with the Australian Government Department of Education, Science and Training (DEST). It is one component of a project to investigate effective third wave intervention strategies for students and learning difficulties that persist beyond the…

  14. Preliminary study on space mutagenesis of mutagenesis of three species of woody plants

    Dry seeds of three woody plants, Xanthoceras sorbifolia, Acer mono and Robiniap pseudoacacia, were carried into space by the return satellite for mutation breeding. The seed vigor,leaf pigments of seedlings, MDA contents and growth volume were analyzed. Compared with the earth control, the seed vigor of three woody plants were extremely improved by space-induced mutation, the seed germination rate, planting and survival rate of seedlings were all higher than those of earth control, and the MDA contents of Xanthoceras sorbifolia and Acer mono were declined. The leaf pigments content of the trees were all lower than those of the control, specially Robinia pseudoacacia and Acer mono, which were both significantly different from their control at 0.01 levels. The growth volume of the mutation group were inhibited in the first year; however, from the second year, the growth of Xanthoceras sorbifolia and Acer mono were faster than those of control, indicating that the space mutation can promote the seed vigor and seedling resistance of three woody plants. (authors)

  15. Molecular identification and expressive characterization of an olfactory co-receptor gene in the Asian honeybee, Apis cerana cerana.

    Zhao, Huiting; Gao, Pengfei; Zhang, Chunxiang; Ma, Weihua; Jiang, Yusuo

    2013-01-01

    Olfaction recognition process is extraordinarily complex in insects, and the olfactory receptors play an important function in the process. In this paper, a highly conserved olfactory co-receptor gene, AcerOr2 (ortholog to the Drosophila melanogaster Or83b), cloned from the antennae of the Asian honeybee, Apis cerana cerana Fabricius (Hymenoptera: Apidae), using reverse transcriptase PCR and rapid amplification of cDNA ends. The full-length sequence of the gene was 1763 bp long, and the cDNA open reading frame encoded 478 amino acid residues, including 7 putative transmembrane domains. Alignment analysis revealed that AcerOr2 shares high homology (> 74%) with similar olfactory receptors found in other Hymenoptera species. The amino acid identity with the closely related species Apis mellifera reached 99.8%. The developmental expression analysis using quantitative real-time reverse transcriptase PCR suggested that the AcerOr2 transcript was expressed at a relatively low level in the larval stage, whereas it was expressed broadly in the pupal and adult stages, with a significantly high level on the days just before and after eclosion. In situ hybridization showed that AcerOr2 mRNA was expressed in sensilla placodea and on the basal region of the worker antennal cuticle, in accordance with the previous conclusions that the conserved genes are expressed in most olfactory receptor neurons. PMID:24224665

  16. Allelopathic activity of tree species leaf litter, soil and coprolites in the dnepropetrovsk parks

    Крючкова, Анжелина Илларионовна; Кульбачко, Юрий Люцинович

    2014-01-01

    The article examines the impact of leaf litter allelopathic properties and earthworms trophy metabolic activity of earthworms (Lumbricidae) on the soil allelopathic properties under the Acer platanoides L., Aesculus hippocastanum L., Ulmus minor Mill. In the Dnepropetrovsk parks. It was established that earthworms trophy metabolic activity positively influenced on soils allelopathic status.

  17. The influence of chemical characteristics of precipitation on tree health in Banjica Forest (Belgrade, Serbia

    Radovanović M.

    2012-01-01

    Full Text Available The most represented tree species in the Banjica Forest are Acer negundo, Quercus robur, Acer pseudoplatanus, Populus nigra, Fraxinus pennsylvanica, Fraxinus ornus and Robinia pseudoacacia. According to the ICP Forests combined assessment (degree of defoliation and decolorization, endangered species are Populus nigra (64.3% of heavily damaged trees, Quercus robur (45.5%, Fraxinus pennsylvanica (37.0% and Acer negundo (26.6%, while the situation is much better for Acer pseudoplatanus and Fraxinus ornus. For Robinia pseudoacacia, 83% of trees are without decolorization, however, defoliation is established. In the period from April to October 2009, the average pH of rainwater was 5.46, and 5.18 in the period from November 2009 to March 2010. The concentration of SO42- in the period from April to October 2009 amounted to an average of 24.21 mg/l, and 28.87 mg/l in the period from November 2009 to March 2010. The concentration of SO42- and pH values is a possible explanation for the condition of the trees. [Acknowledgments. The results are a part of the project III47007 funded by the Ministry of Education and Science of the Republic of Serbia.

  18. Biology of two members of the Euwallacea fornicatus species complex (Coleoptera: Curculionidae: Scolytinae), recently invasive in the USA, reared on an ambrosia beetle artificial diet

    1. Diet and rearing protocols were developed for two members of the cryptic Euwallacea fornicatus species complex, polyphagous shot hole borer (PSHB) and tea shot hole borer (TSHB) (Coleoptera: Curculionidae: Scolytinae), using sawdust from boxelder Acer negundo and avocado Persea americana. 2. Bio...

  19. Synanthropization of dendroflora near main roads in Białystok (NE Poland

    Łaska Grażyna

    2015-06-01

    Full Text Available The aim of the study was to analyze the species composition of the dendroflora near four main roads in the city of Białystok, taking into regard their geographical and historical origin. The wildlife inventory was conducted in the vegetation season of 2011. The inventory revealed presence of a total of 837 trees and bushes representing 36 species and 18 families. The most abundant trees were those from the family Aceraceae (63.8%, while the most abundant bushes were those representing Rosaceae (48.9%. The contribution of native species (65.7% was found to be about twice as high as that of alien ones (34.3%. The dominant species among the native trees was Acer platanoides L., while the principal bush species was Crataegus monogyna Jacq. The alien tree species were most commonly represented by Acer negundo L., and bushes - by Ligustrum vulgare L. Spontaneously settled trees and bushes were clearly dominant (59.9% over those originating from plantations (40.1%. Among the native species of local origin, the prevailing species were synanthropic spontaneophytes (52%, including Acer platanoides and Tilia cordata Mill. Anthropophytes were more abundantly represented by diaphytes (22.7%, followed by kenophytes (10.4%. The most abundant species among diaphytes was Ligustrum vulgare, and among kenophytes - Acer negundo.

  20. Nutrient leaching from container-grown ornamental tree production

    Economically producing marketable container-grown ornamental shade trees with minimum amounts of nutrient leachate requires better management of nutrient applications during a growing season. Fertilizer practices with 16 treatments were used to test the nutrient leachate for growing Acer rubrum ‘Red...

  1. Life Satisfaction of Young Australians: Relationships between Further Education, Training and Employment and General and Career Satisfaction. Longitudinal Surveys of Australian Youth Research Report 43

    Hillman, Kylie; McMillan, Julie

    2005-01-01

    Prepared by the Australian Council for Educational Research (ACER) under an agreement with the Australian Government Department of Education, Science and Training (DEST), this report has three broad aims: (1) To describe the relationship between life satisfaction and participation in a range of post-school education, training and labour market…

  2. Aircraft Cabin Environmental Quality Sensors

    Gundel, Lara; Kirchstetter, Thomas; Spears, Michael; Sullivan, Douglas

    2010-05-06

    The Indoor Environment Department at Lawrence Berkeley National Laboratory (LBNL) teamed with seven universities to participate in a Federal Aviation Administration (FAA) Center of Excellence (COE) for research on environmental quality in aircraft. This report describes research performed at LBNL on selecting and evaluating sensors for monitoring environmental quality in aircraft cabins, as part of Project 7 of the FAA's COE for Airliner Cabin Environmental Research (ACER)1 effort. This part of Project 7 links to the ozone, pesticide, and incident projects for data collection and monitoring and is a component of a broader research effort on sensors by ACER. Results from UCB and LBNL's concurrent research on ozone (ACER Project 1) are found in Weschler et al., 2007; Bhangar et al. 2008; Coleman et al., 2008 and Strom-Tejsen et al., 2008. LBNL's research on pesticides (ACER Project 2) in airliner cabins is described in Maddalena and McKone (2008). This report focused on the sensors needed for normal contaminants and conditions in aircraft. The results are intended to complement and coordinate with results from other ACER members who concentrated primarily on (a) sensors for chemical and biological pollutants that might be released intentionally in aircraft; (b) integration of sensor systems; and (c) optimal location of sensors within aircraft. The parameters and sensors were selected primarily to satisfy routine monitoring needs for contaminants and conditions that commonly occur in aircraft. However, such sensor systems can also be incorporated into research programs on environmental quality in aircraft cabins.

  3. Molecular cloning, prokaryotic expression and lignand-binding characterization of a novel pheromone binding protein OBP10 in Apis cerana cerana (Hymenoptera: Apidae)%中华蜜蜂信息素结合蛋白OBP10的基因克隆、原核表达和配基结合特性分析

    吴帆; 黄君君; 谭静; 唐明珠; 李红亮

    2016-01-01

    [目的]气味结合蛋白在中华蜜蜂Apis cerana cerana嗅觉系统中起到重要作用,本实验拟研究中华蜜蜂一个新的信息素结合蛋白OBP10及其与蜜蜂信息素以及蜜源开花植物挥发物的结合特性.[方法]本实验通过RT-PCR扩增获得OBP10基因全长(GenBank登录号:KP717060.1),以pET-30a构建原核表达载体,并以Ni2+琼脂糖柱进行重组蛋白表达和分离纯化,在N-苯基-1-萘胺(N-phenyl-1-naphthylamine,1-NPN)作为荧光报告子下利用荧光光谱法体外研究重组AcerOBP10与多种候选化学配基的结合特征.[结果]经多序列联配分析,发现AcerOBP10的多个同源基因均为信息素结合蛋白(pheromone binding proteins,PBPs).配基结合特性分析显示,AcerOBP10对14种候选配基中的蜂王信息素成分对羟基苯甲酸甲酯(HOB)竞争力最大,相对荧光可降至6.06%,解离常数11.04μmol/L;进一步表明AcerOBP10属于一个新的中蜂PBPs.此外,AcerOBP10也能和包括工蜂信息素(香叶醇和橙花醇)、报警信息素(2-庚酮和乙酸异戊酯)等蜜蜂信息素以及蜜源开花植物挥发物之一的β-紫罗兰酮结合,表明AcerOBP1O可能是一种以信息素结合为主的多功能结合蛋白.[结论]AcerOBP10是中蜂一个新的信息素结合蛋白,与此前我们鉴定的蜂王信息素结合蛋白AcerASP1相比,AcerOBP10对蜜蜂信息素的结合谱更为广泛,这些结果将对进一步研究中华蜜蜂信息素识别和传递提供理论基础,对于深入了解中华蜜蜂嗅觉影响生理功能的行为机制具有重要意义.

  4. 甘肃省东南部植物分布新纪录%Newly recorded species of plant to Gansu province,China

    徐文斌

    2014-01-01

    报道了甘肃东南部植物分布新纪录4种,即五叶鸡爪茶( Rubus playfairianus Hemsl. ex Focke)、三裂飞蛾槭( Acer oblongum var. trilobum Henry)、西南假毛蕨( Pseudocyclosorus esquirolii ( Christ) Ching)和华中铁角蕨( Asple-nium sarelii Hook.),并对其特征进行了描述。%In this paper, four species in Gansu province are newly recorded, including Rubus playfairianus Hemsl. ex Focke, Acer oblongum var. trilobum Henry, Pseudocyclosorus esquirolii ( Christ) Ching, and Asplenium sarelii Hook.

  5. Impacts of Different Mobile User Interfaces on Students’ Satisfaction for Learning Dijkstra’s Shortest Path Algorithm

    Mazyar Seraj

    2014-10-01

    Full Text Available This paper describes an experimental study of learning Dijkstra’s shortest path algorithm on mobile devices. The aim of the study is to investigate and compare the impacts of two different mobile screen user interfaces on students’ satisfaction for learning the technical subject. A mobile learning prototype was developed for learning Dijkstra’s shortest path algorithm on Apple iPhone 4 operated on iPhone operating system (iOS, and Acer Inconia Tab operated on an Android operating system. Thirty students, who are either currently studying or had previously studied Computer Networks, were recruited for the usability trial. At the end of each single session, students’ satisfaction interacting with the two mobile devices was measured using QUIS questionnaire. Although there is no significant difference in students’ satisfaction between the two different mobile screen interfaces, the subjective findings indicate that Acer Inconia Tab gained higher scores as compared to Apple iPhone 4.

  6. SPECIFIC RESISTANCE AND SPECIFIC INTENSITY OF BELT SANDING OF WOOD

    Boleslaw Porankiewicz

    2010-06-01

    Full Text Available This paper examines and discusses the specific belt sanding resistance K (N·cm-2 and specific belt sanding intensity SI (g·cm-2·min-1, for wood of Pinus sylvestris L., Picea abies L., Quercus robra L., Acer pseudoplatanus L., Alnus glutinosa Gaertn., and Populus Nigra L., by different sanding pressure pS, different sanding grit NG number, and different wood grain angles Phi(v.

  7. The role of bigleaf maple in soil chemistry and nutrient dynamics in coastal temperate forests

    Turk, Tanya D.

    2006-01-01

    The influence of bigleaf maple (Acer macrophyllum Pursh) in a forest dominated by Douglas-fir [Pseudotsuga menziessi (Mirb.) Franco] and western hemlock [Tsuga heterophylla (RAF.) Sarg.] was studied in a paired-plot design through an examination of the annual contribution of bigleaf maple litterfall to nutrient flux, its rate of decay, and its properties within the forest floor and mineral soil. Compared to conifer plots, bigleaf maple plots had litterfall significantly higher in all elements...

  8. Vingt ans de recherche agroforestière en Nouvelle-Zélande : quels enseignements pour l'Europe ? 2ème partie : les pratiques agroforestières néo-zélandaises sont-elles transposables en France ?

    Guitton, J.L.; Dupraz, C.; De Montard, F.X.; Rapey, H.

    1993-01-01

    A brief resume is given of the growth of good quality Pinus radiata timber in New Zealand in conjunction with animal husbandry (either dairy cows or sheep). The potential for such silvopastoral systems to be introduced into France is discussed, and recent French research pertinent to the New Zeland agroforestry trials (in the Auvergne, Corsica, and Provence) is noted. Research has included the use of high-value broadleaves (Juglans sp., Prunus sp., Acer pseudoplatanus) in farm forestry ; or t...

  9. Industrial mineral powder production in China

    2007-01-01

    The recent annual output of major industrial mineral powders in the mainland of China has been more than 100 million t, accompanied by active development of such supporting technology as comminution, classification, separation/purification, and surface modification. In particular, the present paper reviews technologies for preparing ultra-fine particles involving dry and wet processing, modification and composition, calcination of kaolin clay, and processing of spherical/acerous industrial minerals.

  10. Establishing trees on cut-over peatlands in eastern Canada

    J. Bussières; S. Boudreau; L. Rochefort

    2008-01-01

    Four major tree-planting trials on cut-over peatlands in eastern Canada were surveyed in 2002, in order to evaluate the potential use of trees in rehabilitation following horticultural peat extraction. At one of the sites, an experiment to determine the appropriate fertilisation rate for trees planted on cut-over peatlands was also conducted over several years. Tree performance was assessed by measuring survival, total height and annual growth of red maple (Acer rubrum L.), tamarack (Larix la...

  11. 八ヶ岳周辺におけるウラジロモミ林の組成と環境要因

    長岡, 総子; 奥田, 重俊

    1999-01-01

    Species composition and environmental factors of the Abies homolepis forest are investigated around Mt. Yatsugatake in Central Japan. Based on the phytosociological classification, Abies homolepis forests in this area are classified into two communities: Rhododendron wadanum-Abies homolepis and Lonicera demissa-Abies homolepis communities. The former is differentiated by Rhododendron wadanum, Acer distylum, Arachniodes mutica, Fagus crenata and Fagus japonica; the latter, by Lonicera demissa,...

  12. Do ectomycorrhizal and arbuscular mycorrhizal temperate tree species systematically differ in root order-related fine root morphology and biomass?

    Kubisch, Petra; Hertel, Dietrich; Leuschner, Christoph

    2015-01-01

    While most temperate broad-leaved tree species form ectomycorrhizal (EM) symbioses, a few species have arbuscular mycorrhizas (AM). It is not known whether EM and AM tree species differ systematically with respect to fine root morphology, fine root system size and root functioning. In a species-rich temperate mixed forest, we studied the fine root morphology and biomass of three EM and three AM tree species from the genera Acer, Carpinus, Fagus, Fraxinus, and Tilia searching for principal dif...

  13. Conséquences des invasions végétales sur le fonctionnement des écosystèmes riverains fluviaux

    Bottollier-Curtet, Marion

    2010-01-01

    The objective of this work is to evaluate plant species origin importance for biological invasion consequences, through the analysis of the influence of native and exotic dominant plant species for ecosystem functioning. Five pairs of native dominant species (Agrostis stolonifera, Rubus caesius, Populus nigra, Urtica dioica et Salix alba) and exotic invasive species (Paspalum distichum, Fallopia japonica, Buddleja davidii, Impatiens glandulifera et Acer negundo) were compared for litter break...

  14. Multiscale model of a freeze-thaw process for tree sap exudation

    Graf, Isabell; Ceseri, Maurizio; Stockie, John M.

    2015-01-01

    Sap transport in trees has long fascinated scientists, and a vast literature exists on experimental and modelling studies of trees during the growing season when large negative stem pressures are generated by transpiration from leaves. Much less attention has been paid to winter months when trees are largely dormant but nonetheless continue to exhibit interesting flow behaviour. A prime example is sap exudation, which refers to the peculiar ability of sugar maple (Acer saccharum) and related ...

  15. Notebook Positioning by Perceptual Map and Laddering Method

    Mehdi Zaribaf; Nora Shameli

    2012-01-01

    The purpose of this applied paper is to determine positioning of laptops by perceptual map and laddering method. Data collection method was survey using questionnaire. First by using the views of computer experts of selected brands, including Sony, Acer, Asus, Dell and Msi, 5 among 20 attributes, which were considered more important, were selected through application of factor analysis technique. Then, after classification of these features by laddering technique, they were analyzed by using ...

  16. Planetary Pledge Pyramid, Facebook Application

    Pold, Søren; Andersen, Christian Ulrik

    2009-01-01

    Create an Advert X Alt skal væk NU Macbook Air solgt til 370,- kr. Acer Ferrari ONE 200 solgt til 374,- kr. på Ziinga.dk. - Klik her – Like Unlike You like this. X Mindstep | Useful Training® Interesseret i NLP og i at forbedre din bundlinie markant? Nyt NLP Business Practitioner hold i Århus, 19...

  17. Sequences of epicuticular wax structures along stems in four selected tree species

    Tomaszewski Dominik

    2014-09-01

    Full Text Available Wax layer formation accompanies the processes of epidermis and cuticle formation. To examine these changes, observationsalong current-year long shoots of four woody species (Acer negundo, A. rufinerve, Gymnocladus dioica, and Gingko biloba were made. Long shoots are suitable objects for such observations, because from the same stem, several samples can be obtained that represent a well-defined sequence of fragments of different ages.

  18. Trees as Filters of Radioactive Fallout from the Chernobyl Accident

    Brownridge, James D

    2011-01-01

    This paper is a copy of an unpublished study of the filtering effect of red maple trees (acer rubrum) on fission product fallout near Binghamton, NY, USA following the 1986 Chernobyl accident. The conclusions of this work may offer some insight into what is happening in the forests exposed to fallout from the Fukushima Daiichi Nuclear Plant accident. This posting is in memory of Noel K. Yeh.

  19. Combined effects of light and water stress on chloroplast volume regulation.

    McCain, D.C.

    1995-01-01

    A nuclear magnetic resonance technique was used to measure changes in the water content of Acer platanoides chloroplasts in leaf discs that had reached osmotic equilibrium with external solutions either in the dark or under exposure to light. Results showed that chloroplast volume regulation (CVR) maintained constant water content in the chloroplasts over a range of water potentials in the dark, but CVR failed when the water potential fell below a critical value. The critical potential was lo...

  20. Notes on Erysiphales (Ascomycetes) from Patagonia, Argentina

    Havrylenko, Maria; Takamatsu, Susumu

    2005-01-01

    Fifteen Erysiphaceous taxa found on 20 host plant species in Patagonia are documented. A new species Oidium maculatae (type host: Viola maculata) is described. Berberis linearifolia, Buddleja globosa, Prosopis alpataco and Viola maculata, are new host plants for Erysiphales.Three new combinations on fungi and host plant species were founded: Erysiphe howeana – Fuchsia magellanica; E.patagoniaca – Nothofagus pumilio and N. antarctica. The genus Sawadaea and the species S. bicornis on Acer negu...

  1. Interactive Effects of Imazapyr plus Triclopyr ester and Imazapyr plus Glyphosate Mixtures on Woody Weed Seedlings

    Nespeca, Mathew C.

    1997-01-01

    A rapid primary herbicide screening experiment was conducted to determine if synergism or antagonism occurs with imazapyr(Arsenal®) plus triclopyr ester (Garlon 4®) and imazapyr plus glyphosate(Accord®) mixtures applied to woody weed seedlings. Using a booth sprayer, 66 herbicide treatments were applied to greenhouse grown black cherry (Prunus serotina), winged elm (Ulmus alata), sweetgum (Liquidambar styraciflua), red maple (Acer rubrum), black ...

  2. Screening of cognitive impairment in patients with Parkinson's disease: diagnostic validity of the Brazilian versions of the Montreal Cognitive Assessment and the Addenbrooke's Cognitive Examination-Revised

    Emmanuelle Sobreira; Márcio A. Pena-Pereira; Alan L. Eckeli; Manoel A. Sobreira-Neto; Chagas, Marcos H. N.; Maria P. Foss; Brenna Cholerton; Zabetian, Cyrus P.; Mata, Ignacio F.; Vitor Tumas

    2015-01-01

    ABSTRACTObjective The aim of the present study is to examine the accuracy of the Brazilian versions of the Montreal Cognitive Assessment (MoCA) and the Addenbrooke's Cognitive Examination-Revised (ACE-R) to screen for mild cognitive impairment (PDMCI) and dementia (PDD) in patients with Parkinson's disease (PD).Method Both scales were administered to a final convenience sample of 79 patients with PD. Patients were evaluated by a neurologist, a psychiatrist and a neuropsychologist using UPDRS,...

  3. Alkaline ceramidase 1 is essential for mammalian skin homeostasis and regulating whole body energy expenditure

    Liakath-Ali, Kifayathullah; Vancollie, Valerie E.; Christopher J Lelliott; Speak, Anneliese O; Lafont, David; Protheroe, Hayley J; Ingvorsen, Camilla; Galli, Antonella; Green, Angela; Gleeson, Diane; Ryder, Ed; Glover, Leanne; Vizcay-Barrena, Gema; Karp, Natasha A.; Arends, Mark J

    2016-01-01

    Abstract The epidermis is the outermost layer of skin that acts as a barrier to protect the body from the external environment and to control water and heat loss. This barrier function is established through the multistage differentiation of keratinocytes and the presence of bioactive sphingolipids such as ceramides, the levels of which are tightly regulated by a balance of ceramide synthase and ceramidase activities. Here we reveal the essential role of alkaline ceramidase 1 (Acer1) in the s...

  4. Leaf litter decomposition in temperate deciduous forest stands with a decreasing fraction of beech (Fagus sylvatica)

    Jacob, Mascha; Viedenz, Karin; Polle, Andrea; Thomas, Frank

    2010-01-01

    We hypothesised that the decomposition rates of leaf litter will increase along a gradient of decreasing fraction of the European beech (Fagus sylvatica) and increasing tree species diversity in the generally beech-dominated Central European temperate deciduous forests due to an increase in litter quality. We studied the decomposition of leaf litter including its lignin fraction in monospecific (pure beech) stands and in stands with up to five tree genera (Acer spp., Carpinus betulus, Fagus s...

  5. Evidence from micromorphology and gross morphology of the genus Loranthus (Loranthaceae) in Iran

    SHAVVON, ROBABEH SHAHI; MEHRVARZ, Shahryar SAEIDI; GOLMOHAMMADI, Narges

    2012-01-01

    The genus Loranthus L. (Loranthaceae) is represented in Iran by 2 species: Loranthus europaeus Jacq. and L. grewingkii Boiss. & Buhse; the latter species is endemic to the area of Flora Iranica. The plants of Loranthus are hemiparasites growing on various host trees such as Quercus infectoria Oliv., Acer monspessulanum L., and Armeniaca vulgaris Lam. In order to investigate the range of morphological variation in different populations of these species, an inclusive gross morphological and...

  6. Surface energy balance affects gas exchange and growth of two transplanted landscape trees

    Montague, Thayne; Kjelgren, Roger; Rupp, Larry

    2000-01-01

    Research was conducted to investigate how energy balance of bark mulch and turf surfaces influence gas exchange and growth of recently transplanted trees. On several occasions over a 3-year period, stomatal conductance and leaf temperature were measured throughout the day on `Emerald Queen' Norway maple (Acer platanoides L.) and `Greenspire' littleleaf linden (Tilia cordata Mill.) trees growing over each surface. Tree water loss was estimated using a general transport flux equation applied to...

  7. Differential light responses of Mediterranean tree saplings: linking ecophysiology with regeneration niche in four co-occurring species

    Gómez Aparicio, Lorena; VALLADARES, FERNANDO; Zamora Rodríguez, Regino

    2006-01-01

    The ecophysiological mechanisms underlying plant–plant interactions and forest regeneration processes in Mediterranean ecosystems are poorly understood, and the experimental evidence for the role of light availability in these processes is particularly scant.We analyzed the effects of high and lowirradiances on 31 ecological, morphological and physiological variables in saplings of four late-successional Mediterranean trees, two deciduous (Acer opalus subsp. granatense ...

  8. Prilog neofitskoj flori područja rijeke Cetine (Dalmacija, Hrvatska)

    Pandža, Marija; Tafra, Damira

    2008-01-01

    U radu se navode nalazišta 22 neofita uz rijeku Cetinu. Neofiti – Acer negundo L., Amaranthus albus L., A. blitoides S. Watson, Ambrosia artemisiifolia L., Artemisia verlotiorum Lamotte, Conyza bonariensis (L.) Cronq., C. canadensis (L.) Cronq., Eleusine indica (L.) Gaertner, Euphorbia maculata L., E. prostrata Aiton, Galinsoga parviflora Cav., Paspalum paspalodes (Michx.) Scribn., Tagetes minuta L., Xanthium spinosum L., X. strumarium L. subsp. italicum (Moretti) D. Löve prvi put se navode z...

  9. Chamber and field evaluations of air pollution tolerances of urban trees

    Karnosky, D.F.

    1981-04-01

    Results are presented for a study of the relative air pollution tolerances of 32 urban-tree cultivars as determined by both chamber fumigations and field exposures. Tolerances to ozone and sulfur dioxide, alone and in combination, were determined using short-term, acute doses administered while the plants were inside a plastic fumigation chamber located inside the Cary Arboretum greenhouses. In a follow-up study still underway, representatives of the same cultivars were outplanted at four locations in the greater New York City area. To date, only oxidant-type injury has been observed on trees in the field plots. Cultivars tolerant to all chamber and field exposures were Acer platanoides Cleveland, Crimson King, Emerald Queen, Jade Glen, and Summershade; Acer rubrum Autumn Flame and Red Sunset; Acer saccharum Green Mountain and Temple's Upright; Fagus sylvatica Rotundifolia; Fraxinus pennsylvanica Summit; and Ginkgo biloba Fastigate and Sentry. Cultivars sensitive to ozone as determined by the chamber and field tests and that may serve as bioindicators of the presence of ozone were Gleditsia triacanthos inermis imperial and Platanus acerifolia Bloodgood.

  10. Composition and Spatial Pattern of Tree Seedlings in Korean Pine Broadleaved Forest in Changbai Mountains%长白山阔叶红松林乔木树种幼苗组成与空间分布

    陈贝贝; 赵秀海; 倪瑞强; 黄珍

    2012-01-01

    A study was performed to analyze species composition and spatial distribution of tree seedlings based on a permanent plot in Korean pine broadleaved forest in Changbai Mountains as well as field surveys of seedlings and adult trees in the plot. The relationship between mature trees and seedlings was further assessed. Results showed that a total of 1 802 trees were recorded in this plot, among which there were 9 332 tree seedlings. The numbers of Fraxinus mandshurica, Tilia amurensis, Acer mono, A. Tegmentosum, A. Ukurunduensi, A. Pseudo-sieboldianum, A. Barbinerve, Pinus koraiensis, Quercus mongolica, and Maackia amurensis seedlings were 6 986, 832, 394, 250, 123, 289, 438, 3, 10, and 7, respectively. Seedlings of dominate tree species were characterized by clumped distribution on the scales less than certain critical points. When the scales were enlarged beyond these points, seedlings were randomly dispersed. Analysis of spatial relationship showed an unobvious correlation between seedlings of dominate tree species and their mature trees.%以长白山阔叶红松林永久样地为平台,基于该群落幼苗、大树的调查数据,对乔木树种幼苗组成进行初步分析,并运用点格局分析法,对群落中幼苗及幼苗与大树相关关系进行研究.结果表明:该群落物种组成较丰富,共调查到乔木树种大树1 802株,隶属于20种,幼苗9332株,隶属于10种,这些幼苗也是样地内主要乔木树种的组成成分.在1 hm2样地内,共调查到水曲柳(Fraxinus mandshurica)幼苗6 986株,紫椴(Tilia amurensis)幼苗832株,色木槭(Acer mono)幼苗394株,青楷械(Acer tegmentosum)幼苗250株,花楷械(Acer ukurunduensis)幼苗123株,假色槭(Acer pseudo-sieboldianum)幼苗289株,簇毛槭(Acer barbinerve)幼苗438株,红松(Pinus koraiensis)幼苗3株,蒙古栎(Quercus mongolica)幼苗10株,怀槐(Maackia amurensis)幼苗7株.从幼苗的空间分布格局来看,优势树种幼苗在小尺度上呈现聚集分布,随着尺

  11. An analysis of Eemian climate in Western and Central Europe

    Zagwijn, W. H.

    On the basis of 31 pollen diagrams and additional data for botanical macrofossils an analysis is made of the Last Interglacial (Eemian) climatic history in Western and Central Europe. The main tool for this analysis is the climatic indicator species method. Only selected woody species are used for the quantification of data. Partial climatic range diagrams are presented for: Abies alba, Acer monspessulanum, Acer tataricum, Buxus sempervirens, Tilia tomentosa. The problem of time correlation and pollen zonation of the Eemian is discussed. The climatic analysis itself is based on an improved version of the indicator species method. In this version not every site is analysed for its climatic values. Instead maps and tables on the migrational history of Hedera, Ilex, Buxus, Abies and species of Acer, Tilia and Abies are the basis for climatic maps showing respectively January and July isotherms for the periods of the Corylus zone (E4a) and the Carpinus zone (E5). It is concluded that mean January temperatures were as much as 3°C higher at Amsterdam (The Netherlands), than at present, and mean temperatures in July were 2°C higher. However, the thermal maximum in winter was later (zone E5) than the summer thermal maximum (zone E4a). Winter temperatures changed parallel to rise and fall of global sea-level. Precipitation changes are more difficult to estimate. In the first part of the Eemian precipitation must have been relatively low, but from zone E4b onward it increased to higher values, reaching 800 mm and probably substantially more in zones E5 and E6. Hence the Eemian climate was in its beginning relatively more contintental, and later (from E4b onward) more oceanic. However, as compared with the Holocene, the Eemian climate was, generally speaking, more oceanic.

  12. The effect of natural and planted forest stands on soil fertility in the Hyrcanian region, Iran

    RAZIYEH RAFEIE JAHED

    2014-10-01

    Full Text Available Rafeie Jahed R, Hosseini SM, Kooch Y. 2014. The effect of natural and planted forest stands on soil fertility in the Hyrcanian region, Iran. Biodiversitas 15: 206-214. In the present work, we studied the effect of natural and planted forest stands on soil fertility in the Hyrcanian region of northern Iran. Natural forest stands (including Acer velutinum Bioss., Zelkova carpinifolia (Pall, Parrotia persica (DC. C.A.Mey, Quercus castaneifolia C.A. Mey., Carpinus betulus L, Mixed planted stand (including Acer velutinum, Ulmus carpinifolia G. Suckow Quercus castaneifolia C.A. Mey, Carpinus betulus L., Tilia begonifolia Scop. Subsp. caucasia (Rupr. Loria; maple (Acer velutinum Bioss plantation, pine (Pinus taeda L. plantation and also clear-cut region (control were considered in this research. Soil samples were collected at two different depths, i.e., 0-15 and 15-30 cm, and characterized with respect to organic carbon (C, total nitrogen (N, available nutrient elements (P, K, Ca and Mg; pH and soil texture. The results showed that the highest amount of total N was found in mixed plantation. The highest amount of available P was detected in maple plantation and pine plantation had the highest available K and organic C than other treatments. The highest and the lowest available Ca and Mg were found in natural forest and control area, respectively. In addition, it was observed that nutrients accumulate in upper layers of the soil. Hardwood stands have been more successful than the conifers stands, so this should be considered in the sustainable management of forests.

  13. Glucitol-core containing gallotannins inhibit the formation of advanced glycation end-products mediated by their antioxidant potential.

    Ma, Hang; Liu, Weixi; Frost, Leslie; Kirschenbaum, Louis J; Dain, Joel A; Seeram, Navindra P

    2016-05-18

    Glucitol-core containing gallotannins (GCGs) are polyphenols containing galloyl groups attached to a 1,5-anhydro-d-glucitol core, which is uncommon among naturally occurring plant gallotannins. GCGs have only been isolated from maple (Acer) species, including the red maple (Acer rubrum), a medicinal plant which along with the sugar maple (Acer saccharum), are the major sources of the natural sweetener, maple syrup. GCGs are reported to show antioxidant, α-glucosidase inhibitory, and antidiabetic effects, but their antiglycating potential is unknown. Herein, the inhibitory effects of five GCGs (containing 1-4 galloyls) on the formation of advanced glycation end-products (AGEs) were evaluated by MALDI-TOF mass spectroscopy, and BSA-fructose, and G.K. peptide-ribose assays. The GCGs showed superior activities compared to the synthetic antiglycating agent, aminoguanidine (IC50 15.8-151.3 vs. >300 μM) at the early, middle, and late stages of glycation. Circular dichroism data revealed that the GCGs were able to protect the secondary structure of BSA protein from glycation. The GCGs did not inhibit AGE formation by the trapping of reactive carbonyl species, namely, methylglyoxal, but showed free radical scavenging activities in the DPPH assay. The free radical quenching properties of the GCGs were further confirmed by electron paramagnetic resonance spectroscopy using ginnalin A (contains 2 galloyls) as a representative GCG. In addition, this GCG chelated ferrous iron, an oxidative catalyst of AGE formation, supported a potential antioxidant mechanism of antiglycating activity for these polyphenols. Therefore, GCGs should be further investigated for their antidiabetic potential given their antioxidant, α-glucosidase inhibitory, and antiglycating properties. PMID:27101975

  14. Notebook Positioning by Perceptual Map and Laddering Method

    Mehdi Zaribaf

    2012-01-01

    Full Text Available The purpose of this applied paper is to determine positioning of laptops by perceptual map and laddering method. Data collection method was survey using questionnaire. First by using the views of computer experts of selected brands, including Sony, Acer, Asus, Dell and Msi, 5 among 20 attributes, which were considered more important, were selected through application of factor analysis technique. Then, after classification of these features by laddering technique, they were analyzed by using another questionnaire to determine the position of each brand in the perceptual map. We try to show factors and laptop brands position with regard two factors of price and quality in the resulted perceptual map.

  15. Alteraciones de la Función Ejecutiva en la Esquizofrenia

    Toribio Guzmán, José Miguel

    2010-01-01

    [ES] La esquizofrenia es una compleja enfermedad y su heterogeneidad clínica y evolutiva sigue constituyendo un desafío para los investigadores, ha sido considerada desde un principio como un síndrome clínico que afecta diferentes procesos como el pensamiento, la emoción, los movimientos, el comportamiento, y aspectos cognitivos como la memoria, la atención, el lenguaje y especialmente las funciones ejecutivas. El objetivo de este trabajo es revisar la evidencia disponible acer...

  16. Resistencia a la compresión y reología de cementantes ambientalmente amigables

    Lizarazo Marriaga, Juan Manuel; Claisse, Peter

    2010-01-01

    Siendo la producción de cemento responsable de aproximadamente el 9% de la producción industrial de gases de invernadero, y en pro de generar materiales alternativos, en este artículo se presentan los resultados de una investigación encaminada a de- sarrollar cementantes que potencialmente representen una alternativa ambientalmente sostenible en la construcción civil. Com- binaciones de escoria granulada de alto horno, escoria de acería obtenida mediante un proceso de oxígeno básico, polvo ...

  17. Adaptive User Profiling Scheme Using Brain Imaging

    Julián Gaviria Giraldo; Jovani Alberto Jiménez Builes

    2013-01-01

    Introducción. Este artículo muestra cómo la ciencia computacional y laneurociencia cognoscitiva pue- den fusionarse para proponer un esquema efecti- vo de perfilamento. En el área de perfilamiento de usuarios, este artículo provee los caminos y tenden- cias por los cuales ha pasado la investigación acer- ca del tema, y muestra cómo se han pasado por alto algunos aspectos. En otras palabras, este trabajo resolverá efectivamente un punto: la personaliza- ción de contenido a través de la identif...

  18. SYNTHESIS AND FLOCCULABILITY OF SODIUM ALGINATE GRAFTED WITH ACRYLAMIDE

    Kaiqiang Xu; Xiongli Xu; Zhiji Ding; Meihua Zhou

    2006-01-01

    Graft copolymers of sodium alginate (SA) with acrylamide (AM) were synthesized using aceric ion initiated solution polymerization technique. The acrylamide conversions were studied by changing reaction conditions, such as temperature, molecular weight of sodium alginate and reaction time. The flocculation performance of the graft copolymer(SAG) was investigated in kaolin suspension and also in dyeing waste water. It was found that SAG is more efficient in flocculation behavior as compared to polyacrylamide and SA in kaolin suspension, and in removal capacities for CODCr and colority in dyeing wastewater.

  19. mudo brasileño

    Juan Pablo Silva-Escobar

    2014-01-01

    Full Text Available El objetivo de este trabajo es realizar un recorrido histórico y crítico acer- ca del cine mudo brasileño y ver las relaciones significantes y significativas que éste mantiene con la modernidad y la cultura brasileña a través de un conjunto de representaciones y discursos que el cine hace circular masiva- mente. Sostengo que con el cine mudo se da inicio a un imaginario social que contribuye a sustentar la matriz civilizadora de la modernidad: indus- trialización, urbanización, tecnología, racionalización.

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

    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)

  1. INVAZIVNE BILJKE KALNIČKIH ŠUMA

    Horvat, Gabrijel; FRANJIĆ, Jozo

    2016-01-01

    U radu se navode invazivne biljne vrste koje se javljaju u šumama Kalnika. Također se navodi i stanje njihove rasprostranjenosti u Hrvatskoj i njihov utjecaj na šume Kalnika. Ukupno je zabilježeno 14 invazivnih vrsta koje u šumama Kalnika stvaraju probleme, a to su – Acer negundo L. (negundovac), Ailanthus altissima (Mill.) Swingle (pajasen), Ambrosia artemisiifolia L. (ambrozija), Amorpha fruticosa L. (čivitnjača), Asclepias syriaca L. (cigansko perje), Conyza canadensis (L.) Cronquist (kana...

  2. 海南植物增补(Ⅷ)%Some newly recorded plants from Hainan Island of China (Ⅷ)

    秦新生; 严岳鸿; 陈红锋; 邢福武

    2004-01-01

    报道了海南岛5种新记录植物,包括紫果槭Acer cordatum Pax、常春藤Hedera nepalensis var.sinensis (Tobl.) Rehd.、华南龙胆Gentiana loureirii (G.Don) Griseb.、假臭草Eupatorium catarium Veldk.以及假向日葵Tithonia diversifolia A.Gray.引用的标本全部存放在中国科学院华南植物研究所标本馆(IBSC).

  3. MERJENJE STALIŠČ DO NEKATERIH BLAGOVNIH ZNAMK PRENOSNIH RAČUNALNIKOV

    Tonko, Alexander

    2010-01-01

    Dandanes je glavni cilj vsakega podjetja, ki ustanovi lastno blagovno znamko, da bi ta blagovna znamka imela na trgu pozitiven ugled, dejanski in bodoči uporabniki pa pozitivno stališče. Analiza rezultatov raziskave stališč uporabnikov treh blagovnih znamk prenosnih računalnikov »Apple«, »Acer« in »HP« kaže, da ima vsak uporabnik stališče do svoje blagovne znamke,ki pa ni vedno pozitivno. Izmed teh znamk imajo najbolj pozitivno stališče uporabniki blagovne znamke »Apple«, kar je pokazala ...

  4. Ser refugiado y vivir en África. El caso de Mozambique

    Iván Parro Fernández

    2008-01-01

    Hoy ningún lugar del mundo está inmune al problema de los refugiados y de los desplazados. Son personas que huyen sobre todo de las guerras, de las persecuciones, de las sequías, de las hambrunas o de la pobreza y la miseria tan decadentes de sus países. Son personas que únicamente quieren vivir en paz y con un futuro, crear una familia y ser felices viviendo lejos de todo aquello que les oprime y anula las esperanzas de futuro. En este artículo conoceremos algo más sobre estas personas, acer...

  5. Molecular Identification and Expressive Characterization of an Olfactory Co-Receptor Gene in the Asian Honeybee, Apis cerana cerana

    Zhao, Huiting; Gao, Pengfei; Zhang, Chunxiang; Ma, Weihua; Jiang, Yusuo

    2013-01-01

    Olfaction recognition process is extraordinarily complex in insects, and the olfactory receptors play an important function in the process. In this paper, a highly conserved olfactory co-receptor gene, AcerOr2 (ortholog to the Drosophila melanogaster Or83b), cloned from the antennae of the Asian honeybee, Apis cerana cerana Fabricius (Hymenoptera: Apidae), using reverse transcriptase PCR and rapid amplification of cDNA ends. The full-length sequence of the gene was 1763 bp long, and the cDNA ...

  6. Air pollution and the respiration of certain tree species

    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.

  7. Comparative analysis of methods for modelling the short-term probability distribution of extreme wind turbine loads

    Dimitrov, Nikolay Krasimirov

    2016-01-01

    We have tested the performance of statistical extrapolation methods in predicting the extreme response of a multi-megawatt wind turbine generator. We have applied the peaks-over-threshold, block maxima and average conditional exceedance rates (ACER) methods for peaks extraction, combined with four...... levels, based on the assumption that the response tail is asymptotically Gumbel distributed. Example analyses were carried out, aimed at comparing the different methods, analysing the statistical uncertainties and identifying the factors, which are critical to the accuracy and reliability of the...

  8. The impact of urban conditions on different tree species in public green areas in the city of Poznan

    Krzyżaniak Michał; Świerk Dariusz; Walerzak Miłosz; Urbański Piotr

    2015-01-01

    Parks in urbanised areas fulfil an important function as they create a positive climate in cities and contribute to the good health of their inhabitants. The study gives an answer to the question of which of the species under investigation is the most suitable for planting in urbanised areas. The aim of the research conducted from 2013 to 2014 at selected sites in Poznan (Poland) was to determine the state of health of Tilia cordata Mill., Acer platanoides L. and Quercus robur L. trees and to...

  9. Interculturalidad y ciencias de la educación en lengua de señas chilena

    Carolina-Alejandra-de-Lourdes Becerra-Sepúlveda

    2013-01-01

    Los paradigmas de intervención orales para la cultura sorda afectan la percepción sobre la lengua de señas Chilena . Esto provoca debates emanados de una subvaloración, dadas sus particularidades visuales: iconicidad e isomorfismo, subvaloración nacida de una incomprensión en la lectura de investigaciones internacionales (por escasez de estudios nacionales), especialmente acerca del lenguaje corporeizado. Esto se contradice con nuevas investigaciones en psicolingüística cognitiva acer-ca de e...

  10. Nitrogen and media assessment for first-year pot-in-pot production of container and bare root liners in the Intermountain West

    Gunnell, JayDee; Grossl, Paul R.; Kjelgren, Roger

    2008-01-01

    We investigated optimum nitrogen rates and different growth substrates for short-term fi nish production of container and bare root shade tree liners in a pot-in-pot production system in the Intermountain West. In one study, nitrogen ranging from 0–27 g N·tree–1(0–36 lbs N·1000 ft–2) as urea was applied to quaking aspen (Populus tremuloides), ‘Autumn Blaze’ maple (Acer × freemannii ‘Autumn Blaze’), ‘Chanticleer’ flowering pear (Pyrus calleryana ‘Chanticleer’), and ‘Canada Red’ chokecherry (Prun...

  11. Nitrogen and substrate assessment for first-year pot-in-pot production in the Intermountain West.

    Gunnell, JayDee; Grossl, Paul R.; Kjelgren, Roger

    2008-01-01

    We investigated optimum nitrogen rates and different growth substrates for short-term finish production of container and bare root shade tree liners in a pot-in-pot production system in the Intermountain West. In one study, nitrogen ranging from 0–27 g N·tree–1 (0–36 lbs N·1000 ft–2) as urea was applied to quaking aspen n (Populus tremuloides), ‘Autumn Blaze’ maple (Acer × freemannii ‘Autumn Blaze’),'Chanticleer’ flowering pear (Pyrus calleryana ‘Chanticleer’), and ‘Canada Red’ chokecherry (P...

  12. Sumedėjusių augalų grybai ir kenkėjai Vilniaus universiteto botanikos sode

    Grigaliūnaitė, Banga

    2011-01-01

    2003–2011 m. Vilniaus universiteto Botanikos sode tirta 45 genčių sumedėjusių augalų fitosanitarinė būklė. Nustatytos 109 grybų rūšys. Plačiau išplitę ir kiekvienais metais aptinkami yra patogeniniai Diaphorte, Diplodia, Exobasidium, Erysiphe, Gymnosporangium, Guignardia, Laphodermium, Mycosphaerella, Monilinia, Nectria, Pestalotiopsis, Plasmopara, Rhytisma, Thedgonia genčių grybai ir kenkėjai lapinukai (Phyllobius). Labiausiai pažeidžiami šių genčių augalai: Acer, Aesculus, Caragana, Chaenom...

  13. ESQUIZOFRENIA Y TRATAMIENTOS PSICOLÓGICOS: UNA REVISIÓN TEÓRICA - - - SCHIZOPHRENIA AND PSYCHOLOGICAL TREATMENTS: A THEORETICAL REVIEW

    Lina Montaño; Tania Nieto; Nataly Mayorga

    2013-01-01

    La esquizofrenia es un trastorno psiquiátrico que perjudica significativamente el funcionamiento del individuo que lo padece, afectando la percepción, el pensamiento, la afectividad y la conducta; de la misma manera, deteriora de manera importante la interacción social y familiar, además de diversas funciones a nivel neurológico. En el presente artículo se realizó una revisión teórica acerca de los tratamientos más utilizados para enfrentar la esquizofrenia, iniciando con una descripción acer...

  14. Lignin-Furfural Based Adhesives

    Prajakta Dongre; Mark Driscoll; Thomas Amidon; Biljana Bujanovic

    2015-01-01

    Lignin recovered from the hot-water extract of sugar maple (Acer saccharum) is used in this study to synthesize adhesive blends to replace phenol-formaldehyde (PF) resin. Untreated lignin is characterized by lignin content and nuclear magnetic resonance (NMR) analysis. The molecular weight distribution of the lignin and the blends are characterized by size exclusion chromatography (SEC). The effect of pH (0.3, 0.65 and 1), ex situ furfural, and curing conditions on the tensile properties of a...

  15. Lignin-Furfural Based Adhesives

    Prajakta Dongre; Mark Driscoll; Thomas Amidon; Biljana Bujanovic

    2015-01-01

    Lignin recovered from the hot-water extract of sugar maple ( Acer saccharum ) is used in this study to synthesize adhesive blends to replace phenol-formaldehyde (PF) resin. Untreated lignin is characterized by lignin content and nuclear magnetic resonance (NMR) analysis. The molecular weight distribution of the lignin and the blends are characterized by size exclusion chromatography (SEC). The effect of pH (0.3, 0.65 and 1), ex situ furfural, and curing conditions on the tensile properties of...

  16. Uso de la homeopatía unicista en el tratamiento del trastorno ansioso depresivo

    Pinzón Hernández, Johana Carolina

    2015-01-01

    El trastorno ansioso depresivo representa uno de los principales problemas de salud pública en la sociedad actual y uno de los principales motivos de consulta en atención primaria en salud. Se planteó una monografía que describe cual es el enfoque actual a nivel conceptual, de diagnóstico, de tratamiento y de pronóstico, tanto en la medicina convencional como en la homeopatía Unicista de dicho trastorno y posteriormente se realiza una revisión bibliográfica y en diferentes bases de datos acer...

  17. Sexismo y androcentrismo en la escuela técnica : Experiencia de mujeres jóvenes en torno a la sexualidad y la condición juvenil

    Seoane, Viviana

    2012-01-01

    En este trabajo retomamos el uso que le ha dado a la categoría experiencia la teoría feminista para indagar en la subjetividad, las sexualidades y los cuerpos. De este modo experiencia alude, tal como sugiere Teresa De Lauretis, al “proceso por el cual se construye la subjetividad de todos los seres sociales” (1992:253). Entendemos que no es posible sostener una separación tajante entre sujeto y objeto, y que el estudio centrado en las experiencias puede brindarnos información sustantiva acer...

  18. Impacts of Different Mobile User Interfaces on Students’ Satisfaction for Learning Dijkstra’s Shortest Path Algorithm

    Mazyar Seraj; Chui Yin Wong

    2014-01-01

    This paper describes an experimental study of learning Dijkstra’s shortest path algorithm on mobile devices. The aim of the study is to investigate and compare the impacts of two different mobile screen user interfaces on students’ satisfaction for learning the technical subject. A mobile learning prototype was developed for learning Dijkstra’s shortest path algorithm on Apple iPhone 4 operated on iPhone operating system (iOS), and Acer Inconia Tab operated on an Android operating system. Thi...

  19. Absorption of some mineral salts by root system of different woody species and accumulation over a whole vegetative cycle (1963)

    The concentration power of plant tissues and the translocation speed of mineral salts are considerably varying with the absorbed salt, the botanical species, the considered tissue and the part of the vegetative cycle. In Grenoble, with Picea excelsa, the 'true dormancy' is short (half-november, end of december). It is accompanied by a pre-dormancy period (October, half-november) and a post dormancy period (January, february, march). In vegetative period, Picea excelsa leaves are less concentrating mineral salt than Acer campestris leaves (coefficient 2 for calcium - 3 for phosphates) and Populus nigra leaves (coefficient 3 for calcium, coefficient 5 for phosphates). (author)

  20. La reconversión industrial de la siderúrgica integrada en Colombia

    Patricia Carolina Barreto Bernal; Oscar Gutiérrez Molina; Juan Sebastián Lara Rodríguez

    2014-01-01

    La reconversión industrial en Colombia tiene su origen como iniciativa política, buscando modernizar y preparar su aparato productivo, ante la entrada de competidores atraídos por el cambio de modelo económico. Los autores pretenden explicar los principales cambios y transformaciones surgidas en el proceso de reconversión industrial del país, particularmente el caso de Acerías Paz del Río, mediante la implementación de un método hermenéutico y la técnica de análisis documental. Como resultado...

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

    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

  2. Analysis of a sugar maple tree core for monitoring environmental uranium contamination

    Concentrations and isotopic ratios of metals in tree rings can be employed to resolve temporal changes in contamination, but few studies have explored the behavior of uranium (U). This study measured U abundance and isotopic compositions of sugar maple (Acer saccharum) tree rings near the former Fernald Feed Materials Production Center (FFMPC), a U purification facility in Ohio. U concentrations, 235U/238U, and 234U/238U are generally consistent with known events in FFMPC history. Additionally, the outermost rings have compositions consistent with contemporary soil. These results suggest that sugar maple may be reliable for monitoring past and present environmental U contamination. (author)

  3. Facile synthesis of water-soluble carbon nano-onions under alkaline conditions

    Ahmed, Gaber Hashem Gaber; Laíño, Rosana Badía; Calzón, Josefa Angela García; García, Marta Elena Díaz

    2016-01-01

    Carbonization of tomatoes at 240 °C using 30% (w/v) NaOH as catalyst produced carbon onions (C-onions), while solely carbon dots (C-dots) were obtained at the same temperature in the absence of the catalyst. Other natural materials, such as carrots and tree leaves (acer saccharum), under the same temperature and alkaline conditions did not produce carbon onions. XRD, FTIR, HRTEM, UV–vis spectroscopy, and photoluminescence analyses were performed to characterize the as-synthesized carbon nanom...

  4. Antioxidant Activities and Phytochemical Study of Leaf Extracts from 18 Indigenous Tree Species in Taiwan

    Ho, Shang-Tse; Tung, Yu-Tang; Chen, Yong-Long; Zhao, Ying-Ying; Chung, Min-Jay; Wu, Jyh-Horng

    2012-01-01

    The objective of this study is to assess antioxidant activities of methanolic extracts from the leaves of 18 indigenous tree species in Taiwan. Results revealed that, among 18 species, Acer oliverianum exhibited the best free radical scavenging activities. The IC50 values were 5.8 and 11.8 μg/mL on DPPH radical and superoxide radical scavenging activities, respectively. In addition, A. oliverianum also exhibited the strongest ferrous ion chelating activity. Based on a bioactivity-guided isola...

  5. LA “NOCHE” CONSTRUIDA POR LOS VISITANTES DEL MUSEO DE ANTROPOLOGÍA FFYH-UNC. CASO DE ESTUDIO, LA NOCHE DE LOS MUSEOS / The night built by the Museum of Anthropology FFyH-UNC visitors. The Night of the Museums as a case study.

    Mariela Eleonora Zabala; María Cristina De Carli

    2015-01-01

    En este trabajo sistematizamos las opiniones y vivencias que tienen los visitantes del Museo de Antropología de la Facultad de Filosofía y Humanidades de la Universidad Nacional de Córdoba en la propuesta cultural conocida como la Noche de los Museos. Limitamos el análisis a la edición que tuvo lugar el viernes 23 de noviembre de 2012. Lo primero que descubrimos (o percibimos) fue que había una significación especial dada a la visita por tratarse de “la noche”, a partir de ello indagamos acer...

  6. Winter browse selection by white-tailed deer and implications for bottomland forest restoration in the Upper Mississippi River Valley, USA

    Cogger, Benjamin J.; De Jager, Nathan R.; Thomsen, Meredith; Adams, Carrie Reinhardt

    2014-01-01

    White-tailed deer (Odocoileus virginianus) forage selectively, modifying upland forest species composition and in some cases shifting ecosystems to alternative stable states. Few studies, however, have investigated plant selection by deer in bottomland forests. Herbaceous invasive species are common in wetlands and their expansion could be promoted if deer avoid them and preferentially feed on native woody species. We surveyed plant species composition and winter deer browsing in 14 floodplain forest restoration sites along the Upper Mississippi River and tributaries. Tree seedling density declined rapidly with increasing cover of invasive Phalaris arundinacea, averaging less than 1 per m2 in all sites in which the grass was present. Deer browsed ∼46% of available tree seedling stems (branches) at mainland restorations, compared to ∼3% at island sites. Across all tree species, the number of browsed stems increased linearly with the number available and responded unimodally to tree height. Maximum browsing rates were observed on trees with high stem abundances (>10 per plant) and of heights between 50 and 150 cm. Deer preferred Ulmus americana and Acer saccharinum, and avoided Fraxinus pennsylvanica, Acer negundo, and Quercus spp. at mainland sites, and did not browse Phalaris arundinacea if present. Depending on plant growth responses to herbivory and the competitive effects of unbrowsed species, our results suggest that selective foraging could promote the expansion of invasive species and/or alter tree species composition in bottomland forest restorations. Islands may, however, serve as refuges from browsing on a regional scale.

  7. Probability of tree seedling establishment changes across a forest-old field edge gradient.

    Meiners, Scott J; Pickett, Steward T A; Handel, Steven N

    2002-03-01

    Forest edges affect many aspects of plant communities, causing changes in microclimate, species composition, and community structure. However, the direct role of edges in regulating forest regeneration is relatively unknown. The pattern of tree establishment across a forest-old field edge was experimentally examined to determine the response of three tree species to the edge gradient. We placed 100 1-m(2) plots in a 90 × 90 m grid that began 30 m inside the forest, extended across the edge, and ended at 60 m into the old field. Into each plot, we planted seeds of Acer rubrum, Acer saccharum, and Quercus palustris. Emergence increased with distance into the field for both A. saccharum and Q. palustris. Emergence for A. rubrum increased from forest to field, reaching a maximum near 20 m into the field, and then declined with further distance. Nearly all A. rubrum seedlings died shortly after emergence. Survival of A. saccharum increased with distance into the old field, while survivorship of Q. palustris did not respond to the edge gradient. Establishment probabilities increased with distance into the old field for both A. saccharum and Q. palustris. Growth of Q. palustris and allocation patterns of A. saccharum also varied across the edge gradient. These results suggest that edges have complex, species-specific effects on tree establishment and growth that can influence the spatial pattern and species composition of regenerating forests. PMID:21665643

  8. Seasonal variation in N uptake strategies in the understorey of a beech-dominated N-limited forest ecosystem depends on N source and species.

    Li, Xiuyuan; Rennenberg, Heinz; Simon, Judy

    2016-05-01

    In forest ecosystems, species use different strategies to increase their competitive ability for nitrogen (N) acquisition. The acquisition of N by trees is regulated by tree internal and environmental factors including mycorrhizae. In this study, we investigated the N uptake strategies of three co-occurring tree species [European beech (Fagus sylvatica L.), sycamore maple (Acer pseudoplatanus L.) and Norway maple (Acer platanoides L.)] in the understorey of a beech-dominated, N-limited forest on calcareous soil over two consecutive seasons. For this purpose, we studied (15)N uptake capacity as well as the allocation to N pools in the fine roots. Our results show that European beech had a higher capacity for both inorganic and organic N acquisition throughout the whole growing season compared with sycamore maple and Norway maple. The higher capacity of N acquisition in beech indicates a better adaption of beech to the understorey conditions of beech forests compared with the seedlings of other tree competitors under N-limited conditions. Despite these differences, all three species preferred organic over inorganic N sources throughout the growing season and showed similar seasonal patterns of N acquisition with an increased N uptake capacity in summer. However, this pattern varied with N source and year indicating that other environmental factors not assessed in this study further influenced N acquisition by the seedlings of the three tree species. PMID:26786538

  9. Effects of timber harvest on structural diversity and species composition in hardwood forests

    FARZAM TAVANKAR

    2015-04-01

    Full Text Available Tavankar F, Bonyad AE. 2015. Effects of timber harvest on structural diversity and species composition in hardwood forests. Biodiversitas 16: 1-9. Forest management leads to changes in structure and species composition of stands. In this research vertical and horizontal structure and species composition were compared in two harvested and protected stands in the Caspian forest of Iran. The results indicated the tree and seedling density, total basal area and stand volume was significantly (P < 0.01 higher in the protected stand. The Fagus orientalis L. had the most density and basal area in the both stands. Species importance value (SIV of Fagus orientalis in the protected stand (92.5 was higher than in the harvested stand (88.5. While, the SIV of shade-intolerant tree species such as Acer insigne, Acer cappadocicum and Alnus subcordata was higher in the harvested stand. The density of trees and seedling of rare tree species, such as Ulmus glabra, Tilia begonifolia, Zelkova caprinifolia and Fraxinus coriarifolia, was also higher in the protected stand. The Shannon-Wiener diversity index in the protected stand (0.84 was significantly higher (P < 0.01 than in the harvested stand (0.72. The highest diversity value in the harvested stand was observed in DBH of 10-40 cm class, while DBH of 40-70 cm had the highest diversity value in the protected stand.

  10. Cognitive function in schizophrenia and its association with socio-demographics factors

    Bharti T Talreja

    2013-01-01

    Full Text Available Background: Schizophrenia is a chronic and debilitating psychiatric illness consisting primarily of positive and negative symptoms. However, cognitive deficits in various domains have been consistently replicated in patients with schizophrenia. Therefore, the present study was designed to assess cognitive impairment in schizophrenia and to correlate the same with sociodemographic factors. Materials and Methods: Cognitive function in 100 patients with schizophrenia as per Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM IV-TR criteria attending the psychiatry outpatient department (OPD of Department of Psychiatry, SBKS MIRC was assessed using Addenbrooke′s Cognitive Examination Revised (ACER rating scale and Mini Mental State Examination (MMSE and sociodemographic details was obtained using semistructured proforma. Data was analyzed by Chi-square and t-test. Results: About 70% patients of schizophrenia were found to have cognitive dysfunction for attention, concentration, memory, language, and executive function. Positive symptoms were associated with memory (P2 years and belonging to urban habitat showed more cognitive dysfunction. Male patients were associated with impairment in two domains of ACER: Language and memory. Conclusion: The study findings depict that persistent cognitive deficits are seen in patients with schizophrenia. Its correlation with sociodemographic factors showed that patients with >2 years of illness and belonging to urban habitat showed more cognitive dysfunction. Male patients were associated with language and memory impairment. Our study recommends that the neurocognitive impairment should be included in the DSM-V diagnostic criteria for schizophrenia.

  11. Effects of combined gas composing of ozone and sulfur dioxide on trees

    Nouchi, I.; Ohashi, T.; Sawada, T.; Odaira, T.; Hikima, M.; Iwanami, M.

    1974-03-01

    Potted plants 2-3 yrs old were exposed respectively to 15 pphm of ozone, to 45 and 75 pphm of sulfur dioxide, and to a combined gas composed of 16 pphm of ozone and 18 pphm of SO/sub 2/ in an artificially weather controlled room. The damage from ozone consisted mainly of small spots on the surface of grown leaves. The damage appeared earliest on Caroline poplar (9 hr exposure), then on cherry, platanus, and Cersis (18 hr), and did not appear on Acer buergeriana, Quercus myrsinaefolia, Pinus thunbergii and Ginko biloba (60 hr). The symptoms of SO/sub 2/ damage consisted of large necrotic spots between the veins and periphery of grown leaves and of reddish brown spots on grown leaves appearing 6-12 and 12-18 hr after exposure to 75 and 45 pphm, respectively. The damage appeared on all the trees except Acer buergeriana. After exposing trees to the combined gas for 4 days the damage appeared first on Salix babylonica, then on Calorine poplar, followed by platanus, and by cherry (Prunus yedoensis). Damages appeared after 24 hr of 4 days exposure on Pinus thunbergii. The appearance of damage is accelerated by coexposure to ozone and SO/sub 2/. It could not be determined whether the results were additive or multiplicative.

  12. Memory Impairment at Initial Clinical Presentation in Posterior Cortical Atrophy.

    Ahmed, Samrah; Baker, Ian; Husain, Masud; Thompson, Sian; Kipps, Christopher; Hornberger, Michael; Hodges, John R; Butler, Christopher R

    2016-04-23

    Posterior cortical atrophy (PCA) is characterized by core visuospatial and visuoperceptual deficits, and predominant atrophy in the parieto-occipital cortex. The most common underlying pathology is Alzheimer's disease (AD). Existing diagnostic criteria suggest that episodic memory is relatively preserved. The aim of this study was to examine memory performance at initial clinical presentation in PCA, compared to early-onset AD patients (EOAD). 15 PCA patients and 32 EOAD patients, and 34 healthy controls were entered into the study. Patients were tested on the Addenbrooke's Cognitive Examination (ACE-R), consisting of subscales in memory and visuospatial skills. PCA and EOAD patients were significantly impaired compared to controls on the ACE total score (p skills (p skills compared to EOAD patients (p presentation. The findings suggest that memory impairment must be considered in assessment and management of PCA. Further study into memory in PCA is warranted, since the ACE-R is a brief screening tool and is likely to underestimate the presence of memory impairment. PMID:27128371

  13. La reconversión industrial de la siderúrgica integrada en Colombia

    Patricia Carolina Barreto Bernal

    2014-01-01

    Full Text Available La reconversión industrial en Colombia tiene su origen como iniciativa política, buscando modernizar y preparar su aparato productivo, ante la entrada de competidores atraídos por el cambio de modelo económico. Los autores pretenden explicar los principales cambios y transformaciones surgidas en el proceso de reconversión industrial del país, particularmente el caso de Acerías Paz del Río, mediante la implementación de un método hermenéutico y la técnica de análisis documental. Como resultado de la revisión se puede establecer que los procesos de reconversión están relacionados con las formas de gestión organizacional y la disposición de la estructura de capital de la empresa. Para la empresa Acerías el proceso de reconversión resultaría importante para apalancar su perdurabilidad, no obstante las dificultades a las cuales tuvo que hacer frente la gestión de la compañía.

  14. Distribution and trends of mercury in deciduous tree cores

    The distribution of total mercury (THg) within common deciduous trees and the applicability of tree cores as biomonitors of historical environmental THg trends were assessed for both contaminated and reference sites around Kingston, Ontario. Samples were collected from Acer spp., Quercus spp. Populus spp. and Salix spp. Bark and wood THg concentrations were found to be highly correlated whereas soil and wood THg concentrations were not. There were no temporal relationships for THg in dated tree rings corresponding with any other known environmental Hg trends. The shoreline speciess, Populus and Salix spp., had the greatest bark and wood Hg concentrations reaching 18 ng/g, significantly higher than for inland trees Quercus and Acer spp. with maximum values of 7 and 1.2 ng/g for bark and wood respectively. While tree cores cannot be reliably used as temporal THg biomonitors, there is promise for tree species such as Populus spp and Salix spp as spatial indicators of local long-term Hg contamination. - Total mercury trends in several deciduous trees did not follow expected environmental trends. Shoreline species (willow and popular) had higher wood THg than inland species (oak and maple).

  15. ANALYSIS POSITIONING OF NOTEBOOK PRODUCED BY HEWLETT PACKARD (HP IN BALI PROVINCE

    Ni Wayan Sukerayasa

    2009-12-01

    Full Text Available Nowadays notebook is not a luxurious thing any more, but has been one of  the things that should be obligatorily owned by high school student, university student, and practitioners. The competition among the notebooks has been getting tight. The reason is that they have been produced with almost similar attributes, qualities, and design but different prices. This study aims at (1 identifying the similarity between the notebook produced by Hewlett Packard (hp and those produced by its competitors such as, IBM, Sony, Acer and Toshiba, (2 identifying the consumers perception of the notebook produced by Hewlett Packard (hp and of those produced by its competitors, (3 identifying what is the superiority of the notebook produced by Hewlett Packard (hp compared with the superiority of those produced by its competitors, and (4 identifying what strategy is relevant in strengthening the positioning of the notebook produced by Hewlett Packard (hp. The samples were determined by purposive sampling, and the respondents employed totaled 100 spreading over Denpasar City. To achieve maximum result, Multi Dimensional Scaling (MDS was applied as the instrument of analysis to identify the similarity among the notebooks and Correspondence Analysis (CA was employed as the instrument of analysis to identify the superiority of each variable of every notebook. The result of the study show that the notebook produced by Hewlett Packard (hp is perceived to resemble those produced by IBM, Sony, and Toshiba. This means that the notebook produced by Hewlett Packard (hp competes against those produced by IBM, Sony, and Toshiba, and that it does not compete against that produced by Acer. The notebook produced by Hewlett Packard (hp is superior in the variables of product varieties, post sales, distribution channels, and promotion. The notebook produced by IBM superior in the variable product quality, while that produced by Sony is superior in the variable of product  design

  16. Constructing post-carbon institutions: Assessing EU carbon reduction efforts through an institutional risk governance approach

    This paper examines three different governance approaches the European Union (EU) and Member States (MS) are relying on to reach a low carbon economy by 2050. Current governance literature explains the operational methods of the EU's new governance approach to reduce carbon emissions. However, the literature neglects to account for the perceived risks that inhibit the roll-out of new low carbon technology. This article, through a novel approach, uses a grounded theoretical framework to reframe traditional risk literature and provides a connection to governance literature in order to assess the ability of EU governance mechanisms to reduce carbon emissions. The empirical research is based on responses from European energy stakeholders who participated in a Delphi method discussion and in semi-structured interviews; these identified three essential requirements for carbon emissions to be reduced to near zero by 2050: (1) an integrated European energy network, (2) carbon pricing and (3) demand reduction. These features correspond to institutionalized responses by the EU and MS: the Agency for the Cooperation of Energy Regulators (ACER); European Union Emission Trading Scheme (EU ETS) and energy efficiency directives and policies integrated into existing MS institutions. The theoretical and empirical findings suggest that governance by facilitation (energy efficiency) fails to induce significant investment and new policy approaches and cannot be relied on to achieve requisite reductions in demand. Governance by negotiation (ACER) and governance by hierarchy (EU ETS) do reduce risks and may encourage the necessary technological uptake. The term ‘risk governance’ is used to explain the important role governance plays in reducing risks and advancing new technology and thereby lowering carbon emissions in the energy sector. - Highlights: ► This article assesses the role of EU institutions in reducing carbon emissions by 2050. ► Empirical research is based on Delphi

  17. 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

    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.

  18. 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

    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

  19. Application of ant colony algorithm in plant leaves classification based on infrared spectroscopy

    Guo, Tiantai; Hong, Bo; Kong, Ming; Zhao, Jun

    2014-04-01

    This paper proposes to use ant colony algorithm in the analysis of spectral data of plant leaves to achieve the best classification of different plants within a short time. Intelligent classification is realized according to different components of featured information included in near infrared spectrum data of plants. The near infrared diffusive emission spectrum curves of the leaves of Cinnamomum camphora and Acer saccharum Marsh are acquired, which have 75 leaves respectively, and are divided into two groups. Then, the acquired data are processed using ant colony algorithm and the same kind of leaves can be classified as a class by ant colony clustering algorithm. Finally, the two groups of data are classified into two classes. Experiment results show that the algorithm can distinguish different species up to the percentage of 100%. The classification of plant leaves has important application value in agricultural development, research of species invasion, floriculture etc.

  20. Multiscale model of a freeze-thaw process for tree sap exudation

    Graf, Isabell; Stockie, John M

    2015-01-01

    Sap transport in trees has long fascinated scientists, and a vast literature exists on experimental and modelling studies of trees during the growing season when large negative stem pressures are generated by transpiration from leaves. Much less attention has been paid to winter months when trees are largely dormant but nonetheless continue to exhibit interesting flow behaviour. A prime example is sap exudation, which refers to the peculiar ability of sugar maple (Acer saccharum) and related species to generate positive stem pressure while in a leafless state. Experiments demonstrate that ambient temperatures must oscillate about the freezing point before significantly heightened stem pressures are observed, but the precise causes of exudation remain unresolved. The prevailing hypothesis attributes exudation to a physical process combining freeze-thaw and osmosis, which has some support from experimental studies but remains a subject of active debate. We address this knowledge gap by developing the first math...

  1. Contribution of bacterial cell nitrogen to soil humic fractions

    Living cells of Serratia marcescens, uniformly labelled with 15N, were added to samples of maple (Acer saccharum) and black spruce (Picea mariana) forest soils. After different periods of incubation from zero time to 100 days, the soils were subjected to alkali-acid and phenol extraction to provide humic acid, fulvic acid, humin and 'humoprotein' fractions. Significant amounts of the cell nitrogen were recovered in the humic and fulvic acids immediately after addition. After incubation, less cell nitrogen appeared in the humic acid and more in the fulvic acid. The amount of cell nitrogen recovered in the humin fraction increased with incubation. Roughly 5 to 10 per cent of the added cell nitrogen was found as amino acid nitrogen from humoprotein in a phenol extract of the humic acid. The data are consistent with the occurrence of co-precipitation of biologically labile biomass nitrogen compounds with humic polymers during the alkaline extraction procedure involved in the humic-fulvic fractionation. (orig.)

  2. The computational fluid dynamics (CFD) modeling of coolant flow in fuel assembly - current results and their application

    The paper summarises present works performed by VUJE Inc in the field of computational fluid dynamics (CFD) simulation of coolant flow in fuel assemblies used in the WWER-440 reactors. These works are extension of the previous calculations presented on Acer Symposium 2004 and their aim is the better understanding of coolant flow in different parts of fuel assembly. While the previous CFD simulations were focused on study of individual parameters influences on the coolant flow mixing in the upper part of fuel assembly (pin-wise power distribution, geometry of fuel assembly, by-pass flow and coolant flow in central tube), the present works are directed more to verification of previous calculations and joining of individual effects on coolant flow mixing in the upper part of fuel assembly, mainly in the thermocouple position. The main purpose of the CFD simulations of coolant flow in fuel assembly is to increase accuracy of temperature measurements placed at the output of fuel assemblies (Authors)

  3. Version 2.0 of the European Gas Model. Changes and their impact on the German gas sector

    In January 2015 ACER, the European Agency for the Cooperation of Energy Regulators, presented an updated version of its target model for the inner-European natural gas market, also referred to as version 2.0 of the Gas Target Model. During 2014 the existing model, originally developed by the Council of European Energy Regulators (CEER) and launched in 2011, had been analysed, revised and updated in preparation of the new version. While it has few surprises to offer, the new Gas Target Model contains specifies and goes into greater detail on many elements of the original model. Some of the new content is highly relevant to the German gas sector, not least the deliberations on the current key issues, which are security of supply and the ability of the gas markets to function.

  4. STUDY ON POLLEN VIABILITY AS BIOINDICATOR OF AIR QUALITY

    Florentina ŞTEFLEA

    2012-01-01

    Full Text Available The aim of this research is to estimate the relationship between pollen viability and atmospheric pollution (in polluted and non-polluted conditions. The study was carried out in the city of Timisoara. Two areas, with different intensity of road traffic (very high and absent but all characterized by the presence of the same plant species, were selected. The pollen of herbaceous spontaneous species, arboreal species and a shrub species was used (Robinia pseudacacia, Aesculus x carnea, Catalpa bignonioides, Albizzia julibrissin, Rosa canina, Sambucus nigra, Malva neglecta, Ranunculus acer, Trifolium repens, Cichorium intybus. The pollen of these species was treated with TTC (2, 3, 5 Tryphenil-Tetrazolium-Chloride staining solution and viability was then estimated by light microscopy. The results of the mean pollen viability percentage of the examined species are reported. Pollen viability of herbaceous plants is significantly different between the two environments.

  5. Estudi de la viabilitat de l'ús de paviments rígids reforçats amb fibres

    Agustí i Garcia, Joan

    2010-01-01

    Durant els últims anys s’han produït grans avenços en la tecnologia de paviments de formigó que han permès que aquests anessin guanyant força enfront els paviments asfàltics convencionals i que diversos països desenvolupats apostessin per ells en la construcció d’autovies. A més a més, la constant investigació sobre el formigó reforçat amb fibres ha fet que aquest s’anés convertint en una alternativa real al formigó reforçat amb barres d’acer i que el seu ús s’estengués en diverses solucions ...

  6. Dendroflora of the historical park in Rzepiszew (Łódź province

    Paulina Kałczak

    2013-06-01

    Full Text Available The historical, manor park in Rzepiszew was established in the 19th century in the English landscape style. The park and manor have a long and rich history and deserve to be protected. The inventory of dendroflora showed that within the park boundaries grow more thana thousand of arborescent plants deriving from 35 species and 17 families. They are mostly common, native woody plant species, associated with deciduous forests (Alnus glutinosa, Fraxinus excelsior, Carpinus betulus, Acer pseudoplatanus. The most valuable are the magnificent trees. Among all the trees inventoried, 123 splendid trees were found, among which 8 are monuments of nature legally protected and 33 trees with circumferences that exceed minimal values to be protected. Valuable and well-preserved elements of the park are Aesculus hippocastanum and Carpinus betulus alleys. Currently, the park in Rzepiszew is subjected to a gradual naturalization and loses its primary, spatial arrangement, therefore this object requires reassessment.

  7. Natural radioactive trace elements and their occurrence in soil and in plants

    A brief survey is presented on the content of 40K, 238U, 232Th, 206Ra, 87Rb, 208Bi in certain soils in Czechoslovakia. Also presented is a survey of the 40K level in some plants. The level of the trace elements in the soils, expressed in units of 10-6 μCi/100 g soil, was ascertained as varying from 0.0271 to 0.04 for 206Ra to up to 240 for 208Bi. Novel data are also given on the content of 40K in 13 meadow plants for which the level was ascertained to vary between 4,760 (Deschampsia caespitosa P. Beav.) and 17,126 (Ranunculus acer L.) in units of 10-6 μCi/100 g ash. (L.O.)

  8. Nitrogen Deposition Reduces Decomposition Rates Through Shifts in Microbial Community Composition and Function

    Waldrop, M.; Zak, D.; Sinsabaugh, R.

    2002-12-01

    Atmospheric nitrogen (N) deposition may alter soil biological activity in northern hardwood forests by repressing phenol oxidase enzyme activity and altering microbial community composition, thereby slowing decomposition and increasing the export of phenolic compounds. We tested this hypothesis by adding 13C-labelled cellobiose, vanillin, and catechol to control and N fertilized soils (30 and 80 kg ha-1) collected from three forests; two dominated by Acer Saccharum and one dominated by Quercus Alba and Quercus Velutina. While N deposition increased total microbial respiration, it decreased soil oxidative enzyme activities, resulting in slower degradation rates of all compounds, and larger DOC pools. This effect was larger in the oak forest, where fungi dominate C-cycling processes. DNA and 13C-phospolipid analyses showed that N addition altered the fungal community and reduced the activity of fungal and bacterial populations in soil, potentially explaining reduced soil enzyme activities and incomplete decomposition.

  9. Isotope studies to determine dry deposition of sulfate to deciduous and coniferous trees: Final draft

    Experiments have been conducted at two locations near Oak Ridge, Tennessee, with radioactive 35S (87 day half-life) to examine the cycling behavior of sulfur in yellow poplar (Liriodendron tulipifera), red maple (Acer rubrum), and loblolly pine (Pinus taeda) trees. Some findings pertain to methods development for estimating dry deposition of sulfur to forest canopies and the magnitude of sulfur emissions from natural sources (Task II). We will determine through field studies, the internal cycling, storage, and biogenic emission of sulfur, as traced by 35SO42-, in environments impacted by atmospheric sulfate deposition; and will determine through isotope dilution studies, the contribution of foliar leaching and dry deposition to net throughfall (NTF) sulfate concentrations beneath deciduous and coniferous trees in such environments. 3 refs., 2 figs., 1 tab

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

    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

  11. Interculturalidad y ciencias de la educación en lengua de señas chilena

    Carolina-Alejandra-de-Lourdes Becerra-Sepúlveda

    2013-08-01

    Full Text Available Los paradigmas de intervención orales para la cultura sorda afectan la percepción sobre la lengua de señas Chilena . Esto provoca debates emanados de una subvaloración, dadas sus particularidades visuales: iconicidad e isomorfismo, subvaloración nacida de una incomprensión en la lectura de investigaciones internacionales (por escasez de estudios nacionales, especialmente acerca del lenguaje corporeizado. Esto se contradice con nuevas investigaciones en psicolingüística cognitiva acer-ca de embodied cognition . El abordaje de la LSCh a partir de nuevas teorías atraviesa la interculturalidad y educación a fin de proponerse la metáfora de “la cultura en el cuerpo” como modalidad de estudio contemporáneo.

  12. ¿Que nos puede aportar el psicoanálisis en la comprensión de las relaciones en la escuela?

    Alvarado Calderón, Kathia

    2005-01-01

    Este artículo se propone como resultado de la práctica educativa de la autora en ambientes escolares y universitarios. La necesidad de una formación sólida en teoría pedagógica a los estudiantes que inician su formación en Educación es importante, pero también lo es brindarles herramientas para enfrentar las demandas que los ideales educativos culturales imponen tanto a los educadores y educadoras como a los niños, niñas y adolescentes. La propuesta aquí esbozada es una reflexión teórica acer...

  13. Tree damage and mycotrophy

    Heyser, W.; Iken, J.; Meyer, F.H.

    1988-10-22

    Tree species that are particularly endangered in our forests are characterized by the fact that they live in an obligatory symbiosis with ectomycorrhiza fungii. In verifying which tree species appear to be more damaged or less severely damaged, a conspicuous phenomenon noted was that the tree species exhibiting slight symptoms of damage or none at all included such ones as form mycorrhizas facultatively or dispense with mycorrhizas, e.g. Acer, Aesculus, Fraxinus, Populus, Salix. Given that trees in municipal gardens reflect the development and extent of damage in a way similar to forests, and given also that much greater numbers of tree species are often cultured in parks of this type, the latter were considered particularly suited to examine the question of whether a relationship exists between mycotrophy and the severity of damage.

  14. Aerobic biotrickling filtration for biogas desulfurization

    Monzón Montebello, Andrea

    2013-01-01

    Es va gestionar l'operació d'un biofiltre percolador (BTF) durant un període total de 990 dies per a la dessulfuració d'un biogàs sintètic contenint 2,000 ppmv d’H2S (≈ 50 g S-H2S·m-3·h-1), utilitzant un material de rebliment aleatori (anelles Pall d'acer inoxidable). Després de l'optimització de l'operació a pH neutre, es va estudiar l'eliminació simultània de metilmercaptà (CH3SH) i H2S. A continuació es va executar la transició ininterrompuda des de 440 dies a pH neutre (6.0 – 6.5) a 550 d...

  15. KENBAĞI ORMAN FİDANLIĞI (ÇANKIRI )'NDA BULUNAN LEPİDOPTERA TÜRLERİNİN TESPİTİ İLE KAVAK YALANCIARISI [Paranthrene tabaniformis (Rott.)]'NIN MÜCADELE YÖNTEMLERİ ÜZERİNDE ARAŞTIRMALAR

    2002-01-01

    Kenbağı Orman Fidanlığı (Çankırı)\\'nda bulunan Lepidoptera türlerini belirlenmesi ile kavak yalancı arısı [Paranthrene tabaniformis (Rott.)]\\'nın mücadele yöntemlerini belirlemek amacıyla ele alınan bu çalışma 1999-2000 yılında mayıs-eylül ayları arasında yürütülmüştür. Fidanlık, deniz seviyesinden 760 m yükseklikte ve yaklaşık 97 ha genişliktedir. Fidanlıkta Kavak (Populus x euroamericana), Akasya (Robinia pseudoacacia L.), Negundo akçaağaç (Acer ...

  16. Lignin-Furfural Based Adhesives

    Prajakta Dongre

    2015-07-01

    Full Text Available Lignin recovered from the hot-water extract of sugar maple (Acer saccharum is used in this study to synthesize adhesive blends to replace phenol-formaldehyde (PF resin. Untreated lignin is characterized by lignin content and nuclear magnetic resonance (NMR analysis. The molecular weight distribution of the lignin and the blends are characterized by size exclusion chromatography (SEC. The effect of pH (0.3, 0.65 and 1, ex situ furfural, and curing conditions on the tensile properties of adhesive reinforced glass fibers is determined and compared to the reinforcement level of commercially available PF resin. The adhesive blend prepared at pH = 0.65 with no added furfural exhibits the highest tensile properties and meets 90% of the PF tensile strength.

  17. Citizen science identifies the effects of nitrogen dioxide and other environmental drivers on tar spot of sycamore.

    Gosling, Laura; Ashmore, Mike; Sparks, Tim; Bell, Nigel

    2016-07-01

    Elevated sulphur dioxide (SO2) concentrations were the major cause of the absence of symptoms of tar spot (Rhytisma acerinum) of sycamore (Acer pseudoplatanus), in urban areas in the 1970s. The subsequent large decline in SO2 concentrations has not always been accompanied by increased tar spot symptoms, for reasons that have remained unresolved. We used a large citizen science survey, providing over 1000 records across England, to test two competing hypotheses proposed in earlier studies. We were able to demonstrate the validity of both hypotheses; tar spot symptoms were reduced where there were fewer fallen leaves as a source of inoculum, and elevated nitrogen dioxide concentrations reduced tar spot symptoms above a threshold concentration of about 20 μg m(-3). Symptom severity was also lower at sites with higher temperature and lower rainfall. Our findings demonstrate the power of citizen science to resolve competing hypotheses about the impacts of air pollution and other environmental drivers. PMID:27131814

  18. Fossil plants from Romanian deposits of Bacles, Dolj District, Romania

    Nicolae T̡icleanu

    2001-09-01

    Full Text Available From the Middle Romanian lacustrine deposits of the Oltenia province, the authors describe the youngest fossil flora known until now in Oltenia. The inventory of the fossil flora includes the following taxa: Taxodium dubium, ?Platanus platanifolia, Ulmus laevis, Quercus roburoides, Q. cf. muehlenbergii, Carya serraefolia, Acer cf. tricuspidatum and Salix sp. In the Bâcleş fossil flora, Glyptostrobus europaeus, which is a thermophilous and shows a high frequency in all Oltenia area till the XV-th coal seam, is absent. Consequently, having in view the high frequency of Taxodium dubium, which indicate temperate climate conditions, the other consider that the fossil flora from Bâcleş is much more younger and marks an important cooling. From palaeofloristic point of view, the study of Bâcleş fossil flora is indicative for river meadow forest and, probably, flat plain forest environments.

  19. Effects of desiccation and freezing on vitality and field performance of broadleaved tree species

    Radoglou, Kalliopi; Raftoyannis, Yannis

    2001-01-01

    Effets du dessèchement et de la congélation sur la vitalité et la performance des plants d'espèces arborées platyphylles. Des plants d'Acer pseudoplatanus L., Fraxinus ornus L. et Castanea sativa Miller, ont été soumis à des traitements conditionnés contrôlés de dessèchement (15 oC, 50 % HR, mouvement d'air 0.3 m s$^{-1}$, PAR 350 $\\mu$mol m$^{-2}$ s$^{-1}$) et de congélation (à -5 oC, dans l'obscurité). Les effets de ces facteurs de stress sur la qualité des plants ont été établis par la mes...

  20. Classification of Ecological Twin Species and Plant Functional Type for Natural Pinus tabulaeformis Forests in Middle Part of Qinling Mountains%秦岭中段天然油松林生态种对和功能群划分

    蔺雨阳; 王得祥; 雷瑞德; 雍小华

    2009-01-01

    利用20个野外调查的样地资料,分析了油松天然林主要种群种间联结及其生态位重叠特征,结果表明,秦岭中段油松天然林生态种对有8个:山杨-栓皮栎、秦岭木姜子-黄连木、光皮桦-青杄、色木槭-刺叶栎、色木槭-铁杉、盐肤木-槲栎、梾木-少脉椴、桦叶四蕊槭-青榨槭.在此基础上,利用聚类分析结果结合种群的生态位特征,将该区油松天然林划分为4个生态种组,其中油松独立成为了生态关键种的种组.结合生态种对,把第4个生态种组近一步划分为4个功能群:"广泛伴生种"、"嗜热物种"、"嗜湿物种"和"潜在建群种",各功能群都具有明显的生态过程(主要是物理过程和生物过程),能帮助解释物种对生态系统过程影响的机理.生态种对和生态种组两者结合分析植物功能群得出的结果合理,功能群之间的界定也比较清晰,符合各种群的生物学等的特征.%The interspecific association of main populations of natural Pinus tabulaeformis forests in the middle part of Qinling Mountains and the characteristics of niche overlap were analysed base on field investigation. Results show that there are eight preliminary ecological twin species, namely Populus davidiana Dode-Quercus variabilis Blume, Litsea tsinlingensis Yang et P. H. Huang-Pistacia chinensis Bunge, Betula luminifera-Picea wilsonii Mast, Acer mono Maxim-Quercus spinosa David, Acer mono Meaim-Tsuga chinensis ( Franch. ) Pritz, Rhus chinensis WXL-Quercus aliena Blume, Swida macrophylla ( Wall. ) Sojak-Tilia amurensis, and Acer tetramerum Pax var. betulifolium ( Maxim. ) Rehd-Acer davidii Franch. Natural P. tabulaeformis forests in this area are classified into four ecological species groups according to the cluster analysis re-sults , in which Chinese pine become an independent species group of the ecological keystone species. The fourth ecological species group is divided into four plant functional types, all that

  1. Nuclear data evaluation and group constant generation for reactor analysis

    In nuclear or shielding design analysis for reactors including nuclear facilities, nuclear data are one of the primary importances. Research project for nuclear data evaluation and their effective applications has been continuously performed. The objectives of this project are (1) to compile the latest evaluated nuclear data files, (2) to establish their processing code systems, and (3) to evaluate the multigroup constant library using the newly compiled data files and the code systems. As the results of this project, JEF-2.2 which is latest version of Joint Evaluated File developed at OECD/NEA was compiled and COMPLOT and EVALPLOT utility codes were installed in personal computer, which are able to draw ENDF/B-formatted nuclear data for comparison and check. Computer system (NJOY/ACER) for generating continuous energy Monte Carlo code MCNP library was established and the system was validated by analyzing a number of experimental data. (Author)

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

    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...

  3. Distribution and ecology of the lichen Fellhanera gyrophorica in the Pojezierze Olsztyńskie Lakeland and its status in Poland

    Dariusz Kubiak

    2011-12-01

    Full Text Available The study presents recent data on the distribution of Fellhanera gyrophorica (Pilocarpaceae, Ascomycota in Poland, a rare lichen with a crustose, usually sterile thallus. Both previous and new localities of the species are presented with data on its eco­logy and general distribution. Furthermore, this paper provides detailed results on floristic investigations of the species in the forest areas of the Pojezierze Olsztyńskie Lakeland (Northern Poland. Fertile specimens of F. gyrophorica have been observed in Poland for the second time and in the world – for the third time. Also, a new substrate for this species has been found: Acer platanoides. In addition, Carpinus betulus and Populus tremula were also found to be the species' substrates in Poland. Based on this study and previous reports, F. gyrophorica seems to be a relatively common species in north-eastern Poland.

  4. Karyotypes, B-chromosomes and meiotic abnormalities in 13 populations of Alebra albostriella and A. wahlbergi (Hemiptera, Auchenorrhyncha, Cicadellidae from Greece

    Valentina Kuznetsova

    2013-11-01

    Full Text Available In this work 13 populations of the leafhopper species Alebra albostriella (Fallén, 1826 (6 populations and A. wahlbergi (Boheman, 1845 (7 populations (Cicadellidae: Typhlocybinae from Greece were studied cytogenetically. We examined chromosomal complements and meiosis in 41 males of A. albostriella sampled from Castanea sativa, Fagus sylvatica and Quercus cerris and in 21 males of A. wahlbergi sampled from C. sativa, Acer opalus and Ulmus sp. The species were shown to share 2n = 22 + X(0 and male meiosis of the chiasmate preductional type typical for Auchenorrhyncha. In all populations of A. albostriella and in all but two populations of A. wahlbergi B chromosomes and/or different meiotic abnormalities including the end-to-end non-homologous chromosomal associations, translocation chains, univalents, anaphasic laggards besides aberrant sperms were encountered. This study represents the first chromosomal record for the genus Alebra and one of the few population-cytogenetic studies in the Auchenorrhyncha.

  5. Karyotypes, B-chromosomes and meiotic abnormalities in 13 populations of Alebra albostriella and A. wahlbergi (Hemiptera, Auchenorrhyncha, Cicadellidae) from Greece.

    Kuznetsova, Valentina G; Golub, Natalia V; Aguin-Pombo, Dora

    2013-11-26

    In this work 13 populations of the leafhopper species Alebra albostriella (Fallén, 1826) (6 populations) and A. wahlbergi (Boheman, 1845) (7 populations) (Cicadellidae: Typhlocybinae) from Greece were studied cytogenetically. We examined chromosomal complements and meiosis in 41 males of A. albostriella sampled from Castanea sativa, Fagus sylvatica and Quercus cerris and in 21 males of A. wahlbergi sampled from C. sativa, Acer opalus and Ulmus sp. The species were shown to share 2n = 22 + X(0) and male meiosis of the chiasmate preductional type typical for Auchenorrhyncha. In all populations of A. albostriella and in all but two populations of A. wahlbergi B chromosomes and/or different meiotic abnormalities including the end-to-end non-homologous chromosomal associations, translocation chains, univalents, anaphasic laggards besides aberrant sperms were encountered. This study represents the first chromosomal record for the genus Alebra and one of the few population-cytogenetic studies in the Auchenorrhyncha. PMID:24455103

  6. Determination of the pore size of cell walls of living plant cells

    Carpita, N.; Sabularse, D.; Montezinos, D.; Delmer, D.P.

    1979-09-14

    The limiting diameter of pores in the walls of living plant cells through which molecules can freely pass has been determined by a solute exclusion technique to be 35 to 38 angstroms for hair cells of Raphanus sativus roots and fibers of Gossypium hirsutum, 38 to 40 angstroms for cultured cells of Acer pseudoplatanus, and 45 to 52 angstroms for isolated palisade parenchyma cells of the leaves of Xanthium strumarium and Commelina communis. These results indicate that molecules with diameters larger than these pores would be restricted in their ability to penetrate such a cell wall, and that such a wall may represent a more significant barrier to cellular communication than has been previously assumed.

  7. Facile synthesis of water-soluble carbon nano-onions under alkaline conditions

    Ahmed, Gaber Hashem Gaber; Laíño, Rosana Badía; Calzón, Josefa Angela García

    2016-01-01

    Summary Carbonization of tomatoes at 240 °C using 30% (w/v) NaOH as catalyst produced carbon onions (C-onions), while solely carbon dots (C-dots) were obtained at the same temperature in the absence of the catalyst. Other natural materials, such as carrots and tree leaves (acer saccharum), under the same temperature and alkaline conditions did not produce carbon onions. XRD, FTIR, HRTEM, UV–vis spectroscopy, and photoluminescence analyses were performed to characterize the as-synthesized carbon nanomaterials. Preliminary tests demonstrate a capability of the versatile materials for chemical sensing of metal ions. The high content of lycopene in tomatoes may explain the formation of C-onions in alkaline media and a possible formation mechanism for such structures was outlined. PMID:27335764

  8. Effects of grazing on natural regeneration of tree and herb species of Kheyroud forest in northern Iran

    Mohsen Javanmiri Pour; Mohmmad Reza Marvie Mohadjer; Vahid Etemad; Mahmoud Zobeiri

    2012-01-01

    We investigated the effects of grazing on natural regeneration,quantity,and diversity of woody species and dominant herb species in Kheyroud forest in northern Iran.We sampled vegetation in 5m2 plots in custom units,which are demarcated resource areas traditionally used by local livestock producers.The authors quantified number of species,height of seedlings,and diameter of seedlings.Height classes were 0-30 cm,30-130 cm,and >130 cm,and diameter classes were 0-2.5 cm,2.5-5 cm and 5-7.5 cm.The density of seedlings declined with distance from corral until reaching the custom unit boundary.Most seedlings had diameters of 0-2.5 cm and heights of 0-30 cm.Predominant species,Carpinus betulus and Acer capadocicum,were in plots near the centers of custom units,Fagus orientalis,Acer velutinum,Quercus castanifolia species were dominant in plots near the custom unit boundary.Plant species such as Oplismenus undulatifolius,Euphorbia amygdaloides,Rubus fruticos and Pteridium aquilinum were dominant in plots nearer to forest corral.Healthy seedlings were more numerous in plots nearest the corral,while defective and deformed seedlings were more abundant away from the corral.We conclude that grazing had negative effects on the quantity and quality of vegetative regeneration.Continuation of overgrazing will not only endanger the sustainability of forest ecosystems,but also will increase the challenge of sustainable forest management.

  9. Apraxia and motor dysfunction in corticobasal syndrome.

    James R Burrell

    Full Text Available BACKGROUND: Corticobasal syndrome (CBS is characterized by multifaceted motor system dysfunction and cognitive disturbance; distinctive clinical features include limb apraxia and visuospatial dysfunction. Transcranial magnetic stimulation (TMS has been used to study motor system dysfunction in CBS, but the relationship of TMS parameters to clinical features has not been studied. The present study explored several hypotheses; firstly, that limb apraxia may be partly due to visuospatial impairment in CBS. Secondly, that motor system dysfunction can be demonstrated in CBS, using threshold-tracking TMS, and is linked to limb apraxia. Finally, that atrophy of the primary motor cortex, studied using voxel-based morphometry analysis (VBM, is associated with motor system dysfunction and limb apraxia in CBS. METHODS: Imitation of meaningful and meaningless hand gestures was graded to assess limb apraxia, while cognitive performance was assessed using the Addenbrooke's Cognitive Examination - Revised (ACE-R, with particular emphasis placed on the visuospatial subtask. Patients underwent TMS, to assess cortical function, and VBM. RESULTS: In total, 17 patients with CBS (7 male, 10 female; mean age 64.4+/- 6.6 years were studied and compared to 17 matched control subjects. Of the CBS patients, 23.5% had a relatively inexcitable motor cortex, with evidence of cortical dysfunction in the remaining 76.5% patients. Reduced resting motor threshold, and visuospatial performance, correlated with limb apraxia. Patients with a resting motor threshold <50% performed significantly worse on the visuospatial sub-task of the ACE-R than other CBS patients. Cortical function correlated with atrophy of the primary and pre-motor cortices, and the thalamus, while apraxia correlated with atrophy of the pre-motor and parietal cortices. CONCLUSIONS: Cortical dysfunction appears to underlie the core clinical features of CBS, and is associated with atrophy of the primary motor and

  10. Elemental concentrations in deposited dust on leaves along an urbanization gradient

    Environmental health is an essential component of the quality of life in modern societies. Monitoring of environmental quality and the assessment of environmental risks are often species based on the elemental concentration of deposited dust. Our result suggested that stomata size and distribution were the most important factors influencing the accumulation of air contaminants in leaves. We found that the leaves' surfaces of Acer negundo and Celtis occidentalis were covered by a large number of trichomes, and these species have proven to be suitable biomonitors for atmospheric pollution difficult; these can be overcome using bioindicator species. Leaves of Padus serotina, Acer campestre, A. negundo, Quercus robur and C. occidentalis were used to assess the amount of deposited dust and the concentration of contaminants in deposited dust in and around the city of Debrecen, Hungary. Samples were collected from an urban, suburban and rural area along an urbanization gradient. The concentrations of Ba, Cu, Fe, Mn, Ni, Pb, S, Sr and Zn were determined in deposited dust using ICP–OES. Scanning electron microscopy (SEM) was used to explore the morphological structure and dust absorbing capacity of leaves. We found significant differences in dust deposition among species, and dust deposition correlated with trichomes' density. Principal component analysis (PCA) also showed a total separation of tree. - Highlights: • Dust is used as indicators of the accumulation of inorganic pollutants. • Scanning EM was used to explore the morphological structure of leaves. • Amount of dust deposited of leaves correlated with trichomes' density. • A. negundo, C. occidentalis and Q. robur are suitable to indicate air contaminants. • A. negundo and C. occidentalis are suitable to decrease the amount of dust in air

  11. Reconsidering the European regulation of merchant transmission investment in light of the third energy package: The role of dominant generators

    The regulation of merchant transmission investment (MTI) has become an important issue in the EU electricity sector, subsequent to the granting of authorizations by European authorities to five merchant projects: BritNed, Estlink, the East West Cables, NorGer and recently a merchant line connecting Italy and Austria. The creation of a new Agency for the Cooperation of Energy Regulators (ACER) at the EU level, which has decision-making powers on MTI, therefore presents a unique opportunity to question and re-design the current European policy. This paper shows that the recent decisions concerning MTI may suffer a strong bias against dominant electricity generators while incumbent Transmission System Operators (TSOs) or new entrant TSOs are generally favored by national regulators and the European Commission (EC). This strategy is misguided as it fails to recognize both the new incentives of generators to develop MTI and the conflict of interest between the regulated and non-regulated activities of incumbent TSOs. Letting dominant generators undertake MTI is indeed generally beneficial as long as potential abuses of dominance are mitigated. To deter possible anti-competitive effects, we propose a new and feasible allocation of regulatory powers based on a clear demarcation between the market monitoring powers of ACER and the antitrust powers of the EC. - Highlights: → We compare TSOs and generators as merchant transmission investors in Europe. → We find a bias among regulators against the involvement of generators. → The conflict of interest with the regulated activities of TSOs is under-estimated. → Investment by generators is preferable provided market manipulation is deterred. → We propose a new allocation of regulatory powers to make it possible.

  12. Cost-effectiveness analysis of baclofen and chlordiazepoxide in uncomplicated alcohol-withdrawal syndrome

    Vikram K Reddy

    2014-01-01

    Full Text Available Objectives: Benzodiazepines (BZDs are the first-line drugs in alcohol-withdrawal syndrome (AWS. Baclofen, a gamma-aminobutyric acid B (GABA B agonist, controls withdrawal symptoms without causing significant adverse effects. The objective of this study was to compare the cost-effectiveness of baclofen and chlordiazepoxide in the management of uncomplicated AWS. Materials and Methods : This was a randomized, open label, standard controlled, parallel group study of cost-effectiveness analysis (CEA of baclofen and chlordiazepoxide in 60 participants with uncomplicated AWS. Clinical efficacy was measured by the Clinical Institute Withdrawal Assessment for alcohol (CIWA-Ar scores. Lorazepam was used as supplement medication if withdrawal symptoms could not be controlled effectively by the study drugs alone. Both direct and indirect medical costs were considered and the CEA was analyzed in both patient′s perspective and third-party perspective. Results : The average cost-effectiveness ratio (ACER in patient′s perspective of baclofen and chlordiazepoxide was Rs. 5,308.61 and Rs. 2,951.95 per symptom-free day, respectively. The ACER in third-party perspective of baclofen and chlordiazepoxide was Rs. 895.01 and Rs. 476.29 per symptom-free day, respectively. Participants on chlordiazepoxide had more number of symptom-free days when compared with the baclofen group on analysis by Mann-Whitney test (U = 253.50, P = 0.03. Conclusion : Both study drugs provided relief of withdrawal symptoms. Chlordiazepoxide was more cost-effective than baclofen. Baclofen was relatively less effective and more expensive than chlordiazepoxide.

  13. Permeabilidad del arbolado urbano a la radiación solar: Estudio de dos especies representativas en entornos urbanos de baja densidad del Área Metropolitana de Mendoza, Argentina

    Mariela Edith Arboit

    2015-03-01

    Full Text Available El objetivo del trabajo es generar conocimientos que permitan determinar la influencia del arbolado urbano, público o privado, sobre el potencial solar de los entornos urbano- edilicios de baja densidad del Área Metropolitana de Mendoza (AMM. El estudio de la permeabilidad del arbolado urbano ha sido desarrollado para situaciones típicas del área de Capital, Mendoza, representada por especies como: Plátano 21,80%, Morera 32,7%, Fresno europeo 20,95% y Paraíso 2,72% (Cantón, 1994-2000. Sin embargo para determinar la permeabilidad arbórea de entornos urbanos de baja densidad del AMM, en una primera etapa fue necesario realizar una recolección muestral que permitió identificar la presencia de ejemplares no evaluados como Acer 9,95% y Paraíso sombrilla 8,37%. En una segunda etapa, se elaboró un plan de mediciones para un ciclo anual, sobre un conjunto de 8 ejemplares por especie seleccionada. Los resultados obtenidos indican una reducción de la energía solar disponible, del 52,88% al 75,93% en la estación de invierno y del 85,96% al 98,38 % en verano para Acer y Paraíso Sombrilla respectivamente. El estudio ha permitido avanzar en la determinación del potencial solar en ambientes urbanos considerando la permeabilidad de dos especies arbóreas representativas del AMM.

  14. Evaluation of morphological and chemical aspects of different wood species by spectroscopy and thermal methods

    Popescu, Maria-Cristina; Popescu, Carmen-Mihaela; Lisa, Gabriela; Sakata, Yusaku

    2011-03-01

    The aim of this study is to find the most convenient procedure to make an easy differentiation between various kinds of wood. The wood samples used were: fir (Acer alba), poplar (Populus tremula), lime (Tillia cordata), sycamore (Acer pseudoplatanus), sweet cherry (Prunus avium), hornbeam (Carpinus betulus), walnut (Juglans regia), beech (Fagus sylvatica), oak (Quercus robur). The methods of investigation used were FT-IR spectroscopy, X-ray diffraction and thermogravimetry. By FT-IR spectroscopy, was observed that the ratio values of lignin/carbohydrate IR bands for wood decreases with increasing the average wood density, showing a decrease in lignin content. Also, the calculated values of lignin percentage from the FT-IR spectra are in very good correlation with the values from literature. Following the deconvolution process of the X-ray diffraction patterns, it was found that the degree of crystallinity, the apparent lateral crystallite size, the proportion of crystallite interior chains and cellulose fraction tend to increase with increasing of the wood density. Thermal analysis is able to give information about degradation temperatures for the principal components of different wood samples. The shape of DTG curves depends on the wood species that cause the enlargement of the peaks or the maxima of the decomposition step varies at larger or smaller temperatures ranges. The temperatures and weight loss percentage are particular for each kind of wood. This study showed that analytical methods used have the potential to be important sources of information for a quick evaluation of the chemical composition of wood samples.

  15. Modeled effects of soil acidification on long-term ecological and economic outcomes for managed forests in the Adirondack region (USA).

    Caputo, Jesse; Beier, Colin M; Sullivan, Timothy J; Lawrence, Gregory B

    2016-09-15

    Sugar maple (Acer saccharum) is among the most ecologically and economically important tree species in North America, and its growth and regeneration is often the focus of silvicultural practices in northern hardwood forests. A key stressor for sugar maple (SM) is acid rain, which depletes base cations from poorly-buffered forest soils and has been associated with much lower SM vigor, growth, and recruitment. However, the potential interactions between forest management and soil acidification - and their implications for the sustainability of SM and its economic and cultural benefits - have not been investigated. In this study, we simulated the development of 50 extant SM stands in the western Adirondack region of NY (USA) for 100years under different soil chemical conditions and silvicultural prescriptions. We found that interactions between management prescription and soil base saturation will strongly shape the ability to maintain SM in managed forests. Below 12% base saturation, SM did not regenerate sufficiently after harvest and was replaced mainly by red maple (Acer rubrum) and American beech (Fagus grandifolia). Loss of SM on acid-impaired sites was predicted regardless of whether the shelterwood or diameter-limit prescriptions were used. On soils with sufficient base saturation, models predicted that SM will regenerate after harvest and be sustained for future rotations. We then estimated how these different post-harvest outcomes, mediated by acid impairment of forest soils, would affect the potential monetary value of ecosystem services provided by SM forests. Model simulations indicated that a management strategy focused on syrup production - although not feasible across the vast areas where acid impairment has occurred - may generate the greatest economic return. Although pollution from acid rain is declining, its long-term legacy in forest soils will shape future options for sustainable forestry and ecosystem stewardship in the northern hardwood

  16. Elemental concentrations in deposited dust on leaves along an urbanization gradient

    Simon, Edina, E-mail: edina.simon@gmail.com [Department of Ecology, University of Debrecen, H-4010 Debrecen, P.O. Box 71 (Hungary); Baranyai, Edina [Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4010 Debrecen, P.O. Box 21 (Hungary); Agilent Atomic Spectroscopy Partner Laboratory, University of Debrecen, Egyetem tér 1, H-4032 Debrecen (Hungary); Braun, Mihály [Institute of Nuclear Research of the Hungarian Academy of Sciences, Herteleni Laboratory of Environmental Studies, 4026 Debrecen, Bem tér 18/C (Hungary); Cserháti, Csaba [Department of Solid State Physics, University of Debrecen, H-4010 Debrecen, P.O. Box 2 (Hungary); Fábián, István [Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4010 Debrecen, P.O. Box 21 (Hungary); Tóthmérész, Béla [HAS-UD Biodiversity and Ecosystem Services Research Group, H-4010 Debrecen, P.O. Box 71 (Hungary)

    2014-08-15

    Environmental health is an essential component of the quality of life in modern societies. Monitoring of environmental quality and the assessment of environmental risks are often species based on the elemental concentration of deposited dust. Our result suggested that stomata size and distribution were the most important factors influencing the accumulation of air contaminants in leaves. We found that the leaves' surfaces of Acer negundo and Celtis occidentalis were covered by a large number of trichomes, and these species have proven to be suitable biomonitors for atmospheric pollution difficult; these can be overcome using bioindicator species. Leaves of Padus serotina, Acer campestre, A. negundo, Quercus robur and C. occidentalis were used to assess the amount of deposited dust and the concentration of contaminants in deposited dust in and around the city of Debrecen, Hungary. Samples were collected from an urban, suburban and rural area along an urbanization gradient. The concentrations of Ba, Cu, Fe, Mn, Ni, Pb, S, Sr and Zn were determined in deposited dust using ICP–OES. Scanning electron microscopy (SEM) was used to explore the morphological structure and dust absorbing capacity of leaves. We found significant differences in dust deposition among species, and dust deposition correlated with trichomes' density. Principal component analysis (PCA) also showed a total separation of tree. - Highlights: • Dust is used as indicators of the accumulation of inorganic pollutants. • Scanning EM was used to explore the morphological structure of leaves. • Amount of dust deposited of leaves correlated with trichomes' density. • A. negundo, C. occidentalis and Q. robur are suitable to indicate air contaminants. • A. negundo and C. occidentalis are suitable to decrease the amount of dust in air.

  17. Diversity of Riparian Plants among and within Species Shapes River Communities.

    Jackrel, Sara L; Wootton, J Timothy

    2015-01-01

    Organismal diversity among and within species may affect ecosystem function with effects transmitting across ecosystem boundaries. Whether recipient communities adjust their composition, in turn, to maximize their function in response to changes in donor composition at these two scales of diversity is unknown. We use small stream communities that rely on riparian subsidies as a model system. We used leaf pack experiments to ask how variation in plants growing beside streams in the Olympic Peninsula of Washington State, USA affects stream communities via leaf subsidies. Leaves from red alder (Alnus rubra), vine maple (Acer cinereus), bigleaf maple (Acer macrophyllum) and western hemlock (Tsuga heterophylla) were assembled in leaf packs to contrast low versus high diversity, and deployed in streams to compare local versus non-local leaf sources at the among and within species scales. Leaves from individuals within species decomposed at varying rates; most notably thin leaves decomposed rapidly. Among deciduous species, vine maple decomposed most rapidly, harbored the least algal abundance, and supported the greatest diversity of aquatic invertebrates, while bigleaf maple was at the opposite extreme for these three metrics. Recipient communities decomposed leaves from local species rapidly: leaves from early successional plants decomposed rapidly in stream reaches surrounded by early successional forest and leaves from later successional plants decomposed rapidly adjacent to later successional forest. The species diversity of leaves inconsistently affected decomposition, algal abundance and invertebrate metrics. Intraspecific diversity of leaf packs also did not affect decomposition or invertebrate diversity. However, locally sourced alder leaves decomposed more rapidly and harbored greater levels of algae than leaves sourced from conspecifics growing in other areas on the Olympic Peninsula, but did not harbor greater aquatic invertebrate diversity. In contrast to

  18. Sapling herbivory, invertebrate herbivores and predators across a natural tree diversity gradient in Germany's largest connected deciduous forest.

    Sobek, Stephanie; Scherber, Christoph; Steffan-Dewenter, Ingolf; Tscharntke, Teja

    2009-05-01

    Tree species-rich forests are hypothesised to be less susceptible to insect herbivores, but so far herbivory-diversity relationships have rarely been tested for tree saplings, and no such study has been published for deciduous forests in Central Europe. We expected that diverse tree communities reduce the probability of detection of host plants and increase abundance of predators, thereby reducing herbivory. We examined levels of herbivory suffered by beech (Fagus sylvatica L.) and maple saplings (Acer pseudoplatanus L. and Acer platanoides L.) across a tree species diversity gradient within Germany's largest remaining deciduous forest area, and investigated whether simple beech or mixed stands were less prone to damage caused by herbivorous insects. Leaf area loss and the frequency of galls and mines were recorded for 1,040 saplings (>13,000 leaves) in June and August 2006. In addition, relative abundance of predators was assessed to test for potential top-down control. Leaf area loss was generally higher in the two species of maple compared to beech saplings, while only beech showed a decline in damage caused by leaf-chewing herbivores across the tree diversity gradient. No significant patterns were found for galls and mines. Relative abundance of predators on beech showed a seasonal response and increased on species-rich plots in June, suggesting higher biological control. We conclude that, in temperate deciduous forests, herbivory-tree diversity relationships are significant, but are tree species-dependent with bottom-up and top-down control as possible mechanisms. In contrast to maple, beech profits from growing in a neighbourhood of higher tree richness, which implies that species identity effects may be of greater importance than tree diversity effects per se. Hence, herbivory on beech appeared to be mediated bottom-up by resource concentration in the sampled forest stands, as well as regulated top-down through biocontrol by natural enemies. PMID:19238448

  19. 小兴安岭凉水典型阔叶红松林动态监测样地:物种组成与群落结构%Species composition and community structure of a typical mixed broad-leaved-Korean pine (Pinus koraiensis) forest plot in Liangshui Nature Reserve, Northeast China

    徐丽娜; 金光泽

    2012-01-01

    The mixed broadleaved-Korean pine {Pinus koraiensis) forest (MBKF) represents the climax vegetation type of the eastern mountainous area of Northeast China. It is divided into three categories according to community structure and species composition, including southern MBKF, typical MBKF, and northern MBKF. To monitor long-term dynamics of the typical MBKF, we established a 9-ha plot following the field protocol of the 50 ha plot in Panama (Barro Colorado Island, BCI) in 2005 in Liangshui National Nature Reserve of Heilongjiang Province. All free-standing plant species with DBH (diameter at breast height) =1 cm were mapped, tagged, and identified to species in the plot. In the 2010 census, we documented 48 woody species with 21,355 individuals, belonging to 34 genera and 20 families. Most of the species belong to the Changbai Mountain plant flora, with a minor subtropical plant species component. The DBH distribution of all individuals showed a reversed "J" type, indicating well regenerated for the community. The DBH distribution for the canopy, sub-canopy, and middle layers and the understory layer showed the reversed "J" and "L" distributions, respectively. The DBH pattern of the nine dominant species can be classified into three categories: approximate normal, reversed "J", and "L" distribution. Spatial pattern analysis showed that the major tree species were aggregated, and aggregation intensity decreased as DBH increased. Further analysis showed that spatial distribution was closely related to topography and varied with DBH classes. For example, the distribution of Pinus koraiensis and Tilia amurensis was significantly affected by topography (P < 0.05); however, the distribution of Abies nephrolepis, Acer ukurunduense, and Ulmus laciniata correlated significantly with topography at diameter classes of I (DBH < 10 cm) and II (10 cm < DBH < 30 cm). The distribution of Betula costata and Acer tegmentosum was also significantly correlated with topography at a

  20. Retrieval deficiency in brain activity of working memory in amnesic mild cognitive impairment patients: A brain event-related potentials study

    Binyin eLi

    2016-03-01

    Full Text Available In the early stage of Alzheimer disease (AD or mild cognitive impairment (MCI, working memory (WM deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in working memory is impaired in MCI or early AD. We enrolled forty-six subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample task with simultaneous event-related potential (ERP recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2 and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test and visual spatial score of Chinese Addenbrooke’s Cognitive Examination-Revised (ACE-R, while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory

  1. Retrieval Deficiency in Brain Activity of Working Memory in Amnesic Mild Cognitive Impairment Patients: A Brain Event-Related Potentials Study

    Li, Bin-Yin; Tang, Hui-Dong; Chen, Sheng-Di

    2016-01-01

    In the early stage of Alzheimer disease (AD) or mild cognitive impairment (MCI), working memory (WM) deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in WM is impaired in MCI or early AD. We enrolled 46 subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample (DMS) task with simultaneous event-related potential (ERP) recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2, and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test) and visual spatial score of Chinese Addenbrooke's Cognitive Examination-Revised (ACE-R), while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory retrieval. The findings in the

  2. Evaluating the ecological impacts of salvage logging: can natural and anthropogenic disturbances promote coexistence?

    Royo, Alejandro A; Peterson, Chris J; Stanovick, John S; Carson, Walter P

    2016-06-01

    Salvage logging following windthrow is common throughout forests worldwide even though the practice is often considered inimical to forest recovery. Because salvaging removes trees, crushes seedlings, and compacts soils, many warn this practice may delay succession, suppress diversity, and alter composition. Here, over 8 yr following windthrow, we experimentally evaluate how salvaging affects tree succession across 11 gaps in Eastern deciduous forests of Pennsylvania, wherein each gap was divided into salvaged and control (unsalvaged) halves. Our gaps vary in size and windthrow severity, and we explicitly account for this variation as well as variation in soil disturbance (i.e., scarification) resulting from salvaging so that our results would be generalizable. Salvage logging had modest and ephemeral impacts on tree succession. Seedling richness and density declined similarly over time in both salvaged and unsalvaged areas as individuals grew into saplings. The primary impact of salvaging on succession occurred where salvaging scarified soils. Here, salvaging caused 41 to 82% declines in sapling abundance, richness, and diversity, but these differences largely disappeared within 5 yr. Additionally, we documented interactions between windthrow severity and scarification. Specifically, low-severity windthrow and scarification combined reinforced dominance by shade-tolerant and browse-tolerant species (Acer pensylvanicum, Fagus grandifolia). In contrast, high windthrow severity and scarification together reduced the density of a fast-growing pioneer tree (Prunus pensylvanica) and non-tree vegetation cover by 75% and 26%, respectively. This reduction enhanced the recruitment of two mid-successional tree species, Acer rubrum and Prunus serotina, by 2 and 3-fold, respectively. Thus, our findings demonstrate that salvaging creates novel microsites and mitigates competing vegetation, thereby enhancing establishment of important hardwoods and promoting tree species

  3. Forest tree growth response to hydroclimate variability in the southern Appalachians.

    Elliott, Katherine J; Miniat, Chelcy F; Pederson, Neil; Laseter, Stephanie H

    2015-12-01

    Climate change will affect tree species growth and distribution; however, under the same climatic conditions species may differ in their response according to site conditions. We evaluated the climate-driven patterns of growth for six dominant deciduous tree species in the southern Appalachians. We categorized species into two functional groups based on their stomatal regulation and xylem architecture: isohydric, diffuse porous and anisohydric, ring porous. We hypothesized that within the same climatic regime: (i) species-specific differences in growth will be conditional on topographically mediated soil moisture availability; (ii) in extreme drought years, functional groups will have markedly different growth responses; and (iii) multiple hydroclimate variables will have direct and indirect effects on growth for each functional group. We used standardized tree-ring chronologies to examine growth of diffuse-porous (Acer, Liriodendron, and Betula) and ring-porous (Quercus) species vs. on-site climatic data from 1935 to 2003. Quercus species growing on upslope sites had higher basal area increment (BAI) than Quercus species growing on mesic, cove sites; whereas, Acer and Liriodendron had lower BAI on upslope compared to cove sites. Diffuse-porous species were more sensitive to climate than ring porous, especially during extreme drought years. Across functional groups, radial growth was more sensitive to precipitation distribution, such as small storms and dry spell length (DSL), rather than the total amount of precipitation. Based on structural equation modeling, diffuse-porous species on upslope sites were the most sensitive to multiple hydroclimate variables (r(2)  = 0.46), while ring-porous species on upslope sites were the least sensitive (r(2)  = 0.32). Spring precipitation, vapor pressure deficit, and summer storms had direct effects on summer AET/P, and summer AET/P, growing season small storms and DSL partially explained growth. Decreasing numbers of

  4. Hypoglycin A Content in Blood and Urine Discriminates Horses with Atypical Myopathy from Clinically Normal Horses Grazing on the Same Pasture.

    M Bochnia

    Full Text Available Hypoglycin A (HGA in seeds of Acer spp. is suspected to cause seasonal pasture myopathy in North America and equine atypical myopathy (AM in Europe, fatal diseases in horses on pasture. In previous studies, this suspicion was substantiated by the correlation of seed HGA content with the concentrations of toxic metabolites in urine and serum (MCPA-conjugates of affected horses. However, seed sampling was conducted after rather than during an outbreak of the disease. The aim of this study was to further confirm the causality between HGA occurrence and disease outbreak by seed sampling during an outbreak and the determination of i HGA in seeds and of ii HGA and MCPA-conjugates in urine and serum of diseased horses. Furthermore, cograzing healthy horses, which were present on AM affected pastures, were also investigated. AM-pastures in Germany were visited to identify seeds of Acer pseudoplatanus and serum (n = 8 as well as urine (n = 6 from a total of 16 diseased horses were analyzed for amino acid composition by LC-ESI-MS/MS, with a special focus on the content of HGA. Additionally, the content of its toxic metabolite was measured in its conjugated form in body fluids (UPLC-MS/MS. The seeds contained 1.7-319.8 μg HGA/g seed. The content of HGA in serum of affected horses ranged from 387.8-8493.8 μg/L (controls < 10 μg/L, and in urine from 143.8-926.4 μg/L (controls < 10 μg/L, respectively. Healthy cograzing horses on AM-pastures showed higher serum (108.8 ± 83.76 μg/L and urine concentrations (26.9 ± 7.39 μg/L compared to control horses, but lower concentrations compared to diseased horses. The range of MCPA-carnitine and creatinine concentrations found in diseased horses in serum and urine were 0.17-0.65 mmol/L (controls < 0.01, and 0.34-2.05 μmol/mmoL (controls < 0.001, respectively. MCPA-glycine levels in urine of cograzing horses were higher compared to controls. Thus, the causal link between HGA intoxication and disease outbreak

  5. Preliminary results of studies on the distribution of invasive alien vascular plant species occurring in semi-natural and natural habitats in NW Poland

    Popiela Agnieszka

    2015-03-01

    Full Text Available In Western Pomerania, as in other areas of Europe, alien species play an increasingly important role. In particular, invasive plants tend to spread rapidly and in large numbers which may reduce diversity of native species, leading to the phenomenon of “trivialisation of flora”, and transform ecosystems. The list of invasive species (32 taxa includes alien species occurring throughout Western Pomerania, and penetrating natural or semi-natural habitats. The second group consists of potentially invasive species (23 taxa, i.e. those distributed across the area under study and tending to increase the number of their localities in semi-natural and natural habitats, taxa invasive only locally, as well as species with missing data, which does not currently allow including them into the first group. Invasive weeds, as well as some epecophytes and archaeophytes occurring only on anthropogenic sites and tending to spread, were not taken into account. Among hemiagriophytes, the most common and troublesome ones are: Conyza canadensis, Erigeron annuus, Lolium multiflorum, Lupinus polyphyllus, Solidago canadensis, S. gigantea. Among holoagriophytes, i.e. the taxa which received the highest naturalisation status, very expansive species, successful in land colonisation, like Acer negundo, Bidens frondosa, B. connata, Clematis vitalba, Elodea canadensis, Epilobium ciliatum, Heracleum sosnowskyi, Impatiens glandulifera, I. parviflora, Padus serotina, Quercus rubra and Robinia pseudoacacia, should be given particular attention. Among the invasive and potentially invasive species, most taxa penetrate plant communities of the Artemisietea and Molinio-Arrhenatheretea class, followed by Querco-Fagetea, Vaccinio-Piceetea, Stellarietea mediae, Salicetea purpurae and Koelerio-Corynophoretea. The number of invasive species is twice as high when compared to the situation of these species in Poland; on the contrary, the number of species inhabiting anthropogenic, semi

  6. Palynological and palaeobotanical investigations in the Miocene of the Yatağan basin, Turkey: High-resolution taxonomy and biostratigraphy

    Bouchal, Johannes Martin; Güner, Tuncay H.; Denk, Thomas

    2015-04-01

    , Sapindaceae (Acer), Ulmaceae (Cedrelospermum, Ulmus, Zelkova), and Zingiberales (Spirematospermum). In addition, more than two thousand plant macrofossils were collected in the course of repeated field trips, including remains of Pinaceae, Berberidiaceae (Mahonia), Betulaceae (Alnus, Carpinus), Buxaceae (Buxus), Fagaceae (Fagus, Quercus), Lauraceae, Malvaceae (Tilia), Myricaceae (Myrica), Rosaceae, Salicaceae (Populus, Salix), Sapindaceae (Acer), Smilacaceae (Smilax), Typhaceae (Typha), Ulmaceae (Zelkova). A combined analysis integrating these rich and diverse plant macro- and microfossil records will lead to a better understanding and refined reconstruction of the vegetation in the Yatağan basin during the middle to late Miocene.

  7. Retrieval Deficiency in Brain Activity of Working Memory in Amnesic Mild Cognitive Impairment Patients: A Brain Event-Related Potentials Study.

    Li, Bin-Yin; Tang, Hui-Dong; Chen, Sheng-Di

    2016-01-01

    In the early stage of Alzheimer disease (AD) or mild cognitive impairment (MCI), working memory (WM) deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in WM is impaired in MCI or early AD. We enrolled 46 subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample (DMS) task with simultaneous event-related potential (ERP) recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2, and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test) and visual spatial score of Chinese Addenbrooke's Cognitive Examination-Revised (ACE-R), while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory retrieval. The findings in the

  8. Eriophyoid mites from Northeast China (Acari: Eriophyoidea).

    Xue, Xiao-Feng; Guo, Jing-Feng; Hong, Xiao-Yue

    2013-01-01

    We describe and illustrate herein one new genus and eighteen new eriophyoid mite species (Acari: Eriophyoidea) collected in northeast China. They are: Shevtchenkella huzhongiensis sp. nov. on Ulmus davidiana Planch. var. japonica (Sarg. ex Rehder) Nakai (Ulmaceae), Shevtchenkella jingboicus sp. nov. on Acer sp. (Aceraceae), Calepitrimerus flexuosus sp. nov. on Spiraea flexuosa Fisch. ex Cambess. (Rosaceae), Calepitrimerus maximowiczii sp. nov. on Crataegus maximowiczii Schneid. (Rosaceae), Calepitrimerus pilosus sp. nov. on Agrimonia pilosa Ledeb. (Rosaceae), Calepitrimerus yichunensis sp. nov. on Sorbaria sorbifolia (L.) A.Br. (Rosaceae), Cupacarus oxyphyllus sp. nov. on Euonymus oxyphyllus Miq. (Cel-astraceae), Epitrimerus sambucus sp. nov. on Sambucus williamsii Hance (Caprifoliaceae), Epitrimerus wuyingensis sp. nov. on Acer sp. (Aceraceae), Longisolenidionus amurensis gen. nov & sp. nov. on Tilia amurensis Rupr. (Tiliaceae), Phyllocoptes jiagedaqiensis sp. nov. on Cunninghamia sp. (Taxodiaceae), Aculops huzhongensis sp. nov. on Salix sp. (Sali-caceae), Aculus huzhongsalixus sp. nov. on Salix sp. (Salicaceae), Tetra angelica sp. nov. on Angelica sp. (Apiaceae), Tetra jiagedaqia sp. nov. on Lespedeza sp. (Fabaceae), Vittacus mandshurica sp. nov. on Corylus sieboldiana Blume var. mandshurica (Maxim.) C. K. Schneid. (Betulaceae), Vittacus cannabus sp. nov. on Cannabis sativa L. (Moraceae), and Peralox dentatis sp. nov. on Ulmus sp. (Ulmaceae). Two species formerly assigned to Rhyncaphytoptus, R. abiesis (Xue, Song & Hong, 2006) and R. fabris (Xue, Song & Hong, 2006) were reassigned to Nalepella, based on the presence of seta vi on the apical shield, and other characteristics of Nalepella. One species formerly assigned to Rhyncaphytoptus, R. fargesis (Xue, Song & Hong, 2006) was reassigned to Pentaporca, based on the presence of seta vi on the apical shield, opisthosoma with five ridges and other characteristics of Pentaporca. At the same time, four new eriophyoid

  9. CHANGES IN THE ACTIVE FLOODPLAIN VEGETATION OF THE SZIGETKÖZ

    S. BARABAS

    2011-01-01

    , a 30 m wide belt of white willow (Salix alba has developed. Above this, a zone of water-demanding tall forb community has established which tolerates temporary inundation. Further away up to the original shoreline, a strip of vegetation composed of box elder (Acer negundo has appeared. Unlike the white willow belt, this zone developed slowly. At first, knee-high box elder saplings vegetated in the dry grassland, but once their roots has reached permanently wet soil layers, their growth has greatly accelerated. In the former riverbed, the mass appearance of invasive plants (Acer negundo, Ailanthus altissima, Solidago gigantea, Aster lanceolatus, Fallopia x bohemica raises serious concerns for nature protection.

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

    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

  11. Par Pond vegetation status summer 1995 - July survey descriptive summary

    A survey of the emergent shoreline aquatic plant, communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet (61 meters) above mean sea level, and continued with this July survey. Aquatic plant communities, similar to the pre-drawdown Par Pond communities, are becoming reestablished. Beds of maidencane (Panicum hemitomon), lotus (Nelumbo lutea), water lily (Nymphaea odorata), and watershield (Brasenia schreberi) are now extensive and well established. In addition, within isolated coves, extensive beds of water lilies and spike-rush (Eleocharis sp.) are common. Cattail occurrence has increased since refill, but large beds common to Par Pond prior to the drawdown have not formed. Invasion of willow (Salix sp.) and red maple (Acer rubrum) occurred along the lake shoreline during drawdown. The red maples along the present shoreline are beginning to show evidence of stress and mortality from flooding over the past four months. Some of the willows appear to be stressed as well. The loblolly pines (Pinus taeda), which were flooded in all but the shallow shoreline areas, are now dead. Future surveys are planned for the growing seasons of 1995, 1996, and 1997, along with the evaluation of satellite data for mapping the areal extent of the macrophyte beds of Par Pond

  12. High density genome wide genotyping-by-sequencing and association identifies common and low frequency SNPs, and novel candidate genes influencing cow milk traits

    Ibeagha-Awemu, Eveline M.; Peters, Sunday O.; Akwanji, Kingsley A.; Imumorin, Ikhide G.; Zhao, Xin

    2016-01-01

    High-throughput sequencing technologies have increased the ability to detect sequence variations for complex trait improvement. A high throughput genome wide genotyping-by-sequencing (GBS) method was used to generate 515,787 single nucleotide polymorphisms (SNPs), from which 76,355 SNPs with call rates >85% and minor allele frequency ≥1.5% were used in genome wide association study (GWAS) of 44 milk traits in 1,246 Canadian Holstein cows. GWAS was accomplished with a mixed linear model procedure implementing the additive and dominant models. A strong signal within the centromeric region of bovine chromosome 14 was associated with test day fat percentage. Several SNPs were associated with eicosapentaenoic acid, docosapentaenoic acid, arachidonic acid, CLA:9c11t and gamma linolenic acid. Most of the significant SNPs for 44 traits studied are novel and located in intergenic regions or introns of genes. Novel potential candidate genes for milk traits or mammary gland functions include ERCC6, TONSL, NPAS2, ACER3, ITGB4, GGT6, ACOX3, MECR, ADAM12, ACHE, LRRC14, FUK, NPRL3, EVL, SLCO3A1, PSMA4, FTO, ADCK5, PP1R16A and TEP1. Our study further demonstrates the utility of the GBS approach for identifying population-specific SNPs for use in improvement of complex dairy traits. PMID:27506634

  13. Insecticidal Activities of Bark, Leaf and Seed Extracts of Zanthoxylum heitzii against the African Malaria Vector Anopheles gambiae

    Hans J. Overgaard

    2014-12-01

    Full Text Available The olon tree, Zanthoxylum heitzii (syn. Fagara heitzii is commonly found in the central-west African forests. In the Republic of Congo (Congo-Brazzaville its bark is anecdotally reported to provide human protection against fleas. Here we assess the insecticidal activities of Z. heitzii stem bark, seed and leaf extracts against Anopheles gambiae s.s, the main malaria vector in Africa. Extracts were obtained by Accelerated Solvent Extraction (ASE using solvents of different polarity and by classical Soxhlet extraction using hexane as solvent. The insecticidal effects of the crude extracts were evaluated using topical applications of insecticides on mosquitoes of a susceptible reference strain (Kisumu [Kis], a strain homozygous for the L1014F kdr mutation (kdrKis, and a strain homozygous for the G119S Ace1R allele (AcerKis. The insecticidal activities were measured using LD50 and LD95 and active extracts were characterized by NMR spectroscopy and HPLC chromatography. Results show that the ASE hexane stem bark extract was the most effective compound against An. gambiae (LD50 = 102 ng/mg female, but was not as effective as common synthetic insecticides. Overall, there was no significant difference between the responses of the three mosquito strains to Z. heitzii extracts, indicating no cross resistance with conventional pesticides.

  14. The Effect of Edaphic Factors on the Similarity of Parasitic Nematodes in the Soil Sampled in Nurseries of Ornamental Trees and Shrubs

    Chałańska Aneta

    2014-09-01

    Full Text Available The largest faunistic similarity of nematodes was found in soils sampled in coniferous nurseries where arborvitae (Thuja occidentalis - Cupressaceae, spruces (Picea spp. - Pinaceae and pines (Pinus spp. - Pi-naceae were grown. In soil sampled from deciduous tree and shrub nurseries, similar species composition of parasitic nematodes was found in stands of oaks (Quercus spp. - Fagaceae, black locusts (Robiniapseudo-acacia - Fabaceae and maples (Acer spp. - Sapindaceae. In soils, especially the light and medium, from stands of coniferous and deciduous trees and shrubs, Aphelenchus avenae was often isolated. Bitylenchus dubius occurred in both types of nurseries, particularly in light soils. The largest faunistic similarities between nematodes isolated from places of growth of coniferous and deciduous plants were recorded in soils of loamy sand and sandy loam. The most abundant nematode species and the greatest similarity in species of plant parasitic nematodes were observed in soils with neutral pH or slightly acidic. Aphelenchus avenae was found in soil samples collected from both coniferous and deciduous plants, with no relation to soil acidity.

  15. KRAFT PULPING CHARACTERISTICS OF THREE MOROCCAN EUCALYPTI. PART 2. COMPARISON OF THE GUAIACYL FRACTION OF THE NATIVE LIGNINS BY A NOVEL METHOD

    Ericka F. Alves,

    2012-02-01

    Full Text Available In Part 1 of this series it was observed that one of the eucalypti (EGC 39 was more reactive than the other two in kraft and soda-AQ (SAQ cooking. However, the lignin in EGC 39 contained equal or less syringyl (S units than the other two eucalypti. In the present research an attempt was made to compare the guaiacyl (G fraction of the three lignins. The approach was to use SAQ treatment to cleave β-O-4 bonds in dimeric units containing uncondensed guaiacyl A-rings (those rearranging to quinone methides. The coniferyl alcohol, vinylguaiacol and isoeugenol generated from β-O-4 cleavage are then trapped as dimers by ethylguaiacol that is included in the SAQ liquor. Research with sugar maple (Acer saccharum showed that the estimate of these structures (uncondensed G-β-O-4 by this approach was in close agreement with traditional but more tedious methods such as permanganate oxidation and 31P NMR. It was also shown that the lignin in the EGC 39 hybrid contained a higher concentration of uncondensed G-β-O-4 structures than the other two eucalypti lignins.

  16. A review of metal (Pb and Zn) sensitive and pH tolerant bioassay organisms for risk screening of metal-contaminated acidic soils

    To improve risk estimates at the screening stage of Ecological Risk Assessment (ERA), short duration bioassays tailored to undisturbed soil cores from the contaminated site could be useful. However, existing standardized bioassays use disturbed soil samples and often pH sensitive organisms. This is a problem as naturally acidic soils are widespread. Changing soil properties to suit the test organism may change metal bioavailability, leading to erroneous risk estimates. For bioassays in undisturbed soil cores to be effective, species able to withstand natural soil properties must be identified. This review presents a critical examination of bioassay species' tolerance of acidic soils and sensitivity to metal contaminants such as Pb and Zn. Promising organisms include; Dendrobaena octaedra, Folsomia candida, Caenorhabditis elegans, Oppia nitens, Brassica rapa, Trifolium pratense, Allium cepa, Quercus rubra and Acer rubrum. The MetSTICK test and the Bait lamina test were also identified as suitable microorganism tests. -- Highlights: •Risk screening of metal contaminated soils should consider metal bioavailability. •Metal bioavailability is dependent on soil properties such as pH. •Many standardized bioassay organisms are sensitive to acidic soils. •This review identifies acid tolerant and metal sensitive bioassays and species. •The identified tests can improve risk screening of acidic metal contaminated soil. -- This review identifies bioassay species able to withstand naturally acidic soils while being sensitive to metal contaminants

  17. A Quantitative Index of Forest Structural Sustainability

    Jonathan A. Cale

    2014-07-01

    Full Text Available Forest health is a complex concept including many ecosystem functions, interactions and values. We develop a quantitative system applicable to many forest types to assess tree mortality with respect to stable forest structure and composition. We quantify impacts of observed tree mortality on structure by comparison to baseline mortality, and then develop a system that distinguishes between structurally stable and unstable forests. An empirical multivariate index of structural sustainability and a threshold value (70.6 derived from 22 nontropical tree species’ datasets differentiated structurally sustainable from unsustainable diameter distributions. Twelve of 22 species populations were sustainable with a mean score of 33.2 (median = 27.6. Ten species populations were unsustainable with a mean score of 142.6 (median = 130.1. Among them, Fagus grandifolia, Pinus lambertiana, P. ponderosa, and Nothofagus solandri were attributable to known disturbances; whereas the unsustainability of Abies balsamea, Acer rubrum, Calocedrus decurrens, Picea engelmannii, P. rubens, and Prunus serotina populations were not. This approach provides the ecological framework for rational management decisions using routine inventory data to objectively: determine scope and direction of change in structure and composition, assess excessive or insufficient mortality, compare disturbance impacts in time and space, and prioritize management needs and allocation of scarce resources.

  18. An integrated tool to assess the role of new planting in PM{sub 10} capture and the human health benefits: A case study in London

    Tiwary, Abhishek [School of Chemical Engineering and Analytical Sciences, Environment and Sustainable Technology Division, University of Manchester, PO Box 88, Sackville St, Manchester, M60 1QD (United Kingdom); Sinnett, Danielle, E-mail: danielle.sinnett@forestry.gsi.gov.u [Land Regeneration and Urban Greenspace Research Group, Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey, GU10 4LH (United Kingdom); Peachey, Christopher [Land Regeneration and Urban Greenspace Research Group, Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey, GU10 4LH (United Kingdom); Chalabi, Zaid; Vardoulakis, Sotiris; Fletcher, Tony [Public and Environmental Health Research Unit, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom); Leonardi, Giovanni [Centre for Radiation, Chemical, and Environmental Health Hazards, Health Protection Agency, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom); Grundy, Chris [Public and Environmental Health Research Unit, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom); Azapagic, Adisa [School of Chemical Engineering and Analytical Sciences, Environment and Sustainable Technology Division, University of Manchester, PO Box 88, Sackville St, Manchester, M60 1QD (United Kingdom); Hutchings, Tony R. [Land Regeneration and Urban Greenspace Research Group, Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey, GU10 4LH (United Kingdom)

    2009-10-15

    The role of vegetation in mitigating the effects of PM{sub 10} pollution has been highlighted as one potential benefit of urban greenspace. An integrated modelling approach is presented which utilises air dispersion (ADMS-Urban) and particulate interception (UFORE) to predict the PM{sub 10} concentrations both before and after greenspace establishment, using a 10 x 10 km area of East London Green Grid (ELGG) as a case study. The corresponding health benefits, in terms of premature mortality and respiratory hospital admissions, as a result of the reduced exposure of the local population are also modelled. PM{sub 10} capture from the scenario comprising 75% grassland, 20% sycamore maple (Acer pseudoplatanus L.) and 5% Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) was estimated to be 90.41 t yr{sup -1}, equating to 0.009 t ha{sup -1} yr{sup -1} over the whole study area. The human health modelling estimated that 2 deaths and 2 hospital admissions would be averted per year. - A combination of models can be used to estimate particulate matter concentrations before and after greenspace establishment and the resulting benefits to human health.

  19. Sample preservation for determination of organic compounds: microwave versus freeze-drying

    In search of a reliable drying method, which might be used even under field conditions, microwave drying was compared to freeze-drying of plant material. Leaves of Ananas comosus and Avicennia germinans as well as buds and phloem of Acer pseudoplatanus were used and checked for one or more of the following substances: sugars, sugar alcohols, organic and amino acids, total nitrogen, and glycinebetaine. With most samples good agreement was achieved between the two drying methods. Only in the case of the Ananas comosus leaves, which exhibited low pH and high water content, did appreciable differences occur in organic and amino acids. Besides that, sucrose was the compound most susceptible to alterations, which was especially evident when leaves of Sambucus nigra were dried in the two different compartments (condenser compartment, drying bell jar) of the freeze-dryer in use. For Ananas comosus leaf samples it was shown that microwaving can also be used prior to extraction of tissue sap. (author)

  20. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition

    Li, Yongfu; Chen, Na; Harmon, Mark E.; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A.; Mao, Jingdong

    2015-10-01

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11 litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced 13C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species.

  1. Experiencias de investigación en tecnologías de biorremediación: Revisión para un planteamiento experimental de biorremediación en aguas residuales generadas por la fabricación de coque de hulla

    Sánchez Nieves Jimena

    2004-12-01

    Full Text Available Se presenta una revisión de literatura que identifica los datos y experimentos relevantes para plantear metodologías de biorremediación como parte de un sistema de tratamiento de aguas residuales generadas por la fabricación de coque de hulla. Tras el análisis de los documentos
    consultados se identifican y describen tres tipos de aguas residuales generadas por este proceso minero-industrial: lixiviados, agua de lavado y agua contaminada de coquería. Con base en las caracterizaciones disponibles para el caso de la coquería de la empresa siderúrgica Acerías Paz del Río, restringidas a agua contaminada de coquería, se discute la pertinencia del uso de herramientas metodológicas de biorremediación en el planteamiento de un sistema de tratamiento de esta agua residual industrial. Finalmente, con el objetivo de guiar la experimentación
    que evalúe los análisis realizados en esta monografía, se presentan un protocolo experimental y una clave dicotómica; ésta última constituye una herramienta para la selección de pasos subsecuentes y de métodos específicos que aseguren la mayor depuración del agua contaminada
    de coquería.

  2. Plant resources in seven Jeonju City reservoirs: Osongjae, Gisijae, Sunggokjae, Gujujae, Seounjae, Hwanghakjae and Hacksojae

    Dong-Ok Lim

    2014-09-01

    Full Text Available The vascular plants of the seven reservoirs of Jeonju City were identified as consisting of 309 taxa; 87 families, 231 genera, 270 species, 35 varieties, and four forms. Eight taxa of endemic Korean plants were identified, including Taxus cuspidata var. caepitosa and Aster koraiensis. Ten taxa of rare and endangered species were identified, including T. cuspidata and Penthorum chinense. A total of 26 taxa of floristic special plants were recorded: class V species (5 taxa included Magnolia kobus and Prunus yedoensis; class IV species (3 taxa included Prunus davidiana and Campanula takesimana; class III species (5 taxa included Acer palmatum and Alisma orientale. The hydrophytes of the seven reservoirs of Jeonju City were investigated and, of a total of 56 taxa, 46 taxa of emerged plants, two taxa of submerged plants, five taxa of floating-leaved plants, and three taxa of floating plants were identified. Thirty-two taxa of naturalized plants were identified. Among these, Sicyos angulatus, Lactuca scariola, Paspalum distichum var. indutum and P. distichum were identified, which are all wild plants that may disturb the ecosystem. The study suggests that these areas require management for the physical removal of these wild plants.

  3. Customization of ENDF/B-VI and JENDL3.2 basic data for MCNP calculation and measurements on neutron cross section at INST, AERE, Savar

    Bhuiyan, S.I.; Molla, N.I.; Chakrobortty, T.K.; Huda, M.Q.; Mondal, M.A.W. [Institute of Nuclear Science and Technology (INST), Atomic Energy Research Establishment, Savar, Dhaka (Bangladesh)

    2000-03-01

    The NJOY94.10{sup +}, a version of NJOY, has been installed in a VAX computer under Open VMS operating system. ENDF/B-VI, latest release of ENDF data, has been also implemented in the same system. A data library has been processed using the modules RECONR, BROADR and ACER of NJOY code. MCNP4B2 computer code has been used to validate the prepared data library for some benchmark experiments. The results obtained have been found to be in good agreement with the experimental results. Excitation function have been measured for {sup 81}Br(n,alpha){sup 78}As, {sup 79}Br(n,alpha){sup 76}As, {sup 73}Ge(n,p){sup 73}Ga, {sup 72}Ge(n,p){sup 72}Ga, {sup 64}Zn(n,p){sup 64}Cu, {sup 68}Zn(n,alpha){sup 65}Ni, and {sup 70}Zn(n,2n){sup 69m}Zn reactions in the neutron energy range 13.57-14.71 MeV via Activation technique. (author)

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

    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.

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

    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.

  6. Deposition of particulate matter of different size fractions on leaf surfaces and in waxes of urban forest species.

    Dzierzanowski, Kajetan; Popek, Robert; Gawrońska, Helena; Saebø, Arne; Gawroński, Stanislaw W

    2011-01-01

    Particulate matter (PM) is an air contaminant in urban and industrial areas that often exceeds limit values, creating serious problems due to its harmful effects on health. Planting trees and shrubs as air filters is a way to improve air quality in these areas. However,further knowledge on species effectiveness in air purification is essential This study compared four species of tree (Acer campestre L, Fraxinus excelsior L, Platanus x hispanica Mill. ex Muenchh. 'Acerifolia', Tilia cordata Mill.), three species of shrub (Forsythia x intermedia Zabel, Physocarpus opulifolius (L.) Maxim., Spiraea japonica L.), and one climber species (Hedera helix L) that are commonly cultivated along streets in Poland to capture fine, coarse and larger particles from air. Separate gravimetric analyses were performed to quantify PM deposited on surfaces and trapped in waxes. Significant differences were found between the plant species tested. The distribution of different particle size fractions differed between and within species and also between leaf surfaces and in waxes. PMID:21972570

  7. Nutritional Value of Seaweed to Ruminants

    Roger D. Applegate

    1995-12-01

    Full Text Available We compared the nutritional quality (apparent digestible dry matter (ADDM, crude protein, total phenolics, gross energy, of 3 seaweed species (Alaria esculenta, Ascophyllum nodosum, Fucus vesiculosis to that of 3 woody browse species{Acer rubrum, Thuja occidentalis, Abies balsamea, lichen (Usnea spp., and winter rye (Secale cereals for ruminants. The ADDM's of the 3 seaweeds (63-80% DM were 11-167% DM higher and crude protein contents (12.1-14.6% DM were 68-186% DM higher than the 3 browse species. Seaweeds had lower total phenolics (5.5-10.3% DM and gross energy (12-15 KJ/g DM, and moderate digestible energy (DE contents (9-10 KJ/g DM compared to the browse species. The 3 browse species had ADDM's of 30-57% DM, crude protein contents of 5.1-7.2% DM, total phenolic concentrations of 11.6-16.4% DM, and DE contents of 6-12 KJ/g DM. Winter rye and lichen had the lowest total phenolic concentrations (1.3 and 1.9% DM of forages examined, and had lower ADDM's (35 and 40% DM, DE contents (6-7 KJ/g DM, and crude protein (7.8 and 5.7% DM than seaweeds. The relatively high DE and protein contents of seaweed may explain high deer densities of Maine coastal islands where browse availability and use appears to be low.

  8. Diet and nutrient balance of red panda in Nepal

    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.

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

    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.

  10. Inventory of epiphytic macrolichens on trees used in urban arborization in Curitiba, Paraná, Brazil

    Lucas Nogueira

    2009-12-01

    Full Text Available The floristic composition of epiphytic macrolichens on the following tree species used in urban arborization in Curitiba was analysed: Acer negundo, Lagerstroemia indica, Ligustrum lucidum, Parapiptadenia rigida, Cassia leptophylla, Syagrus romanzoffi ana, Tabebuia alba, Tabebuia chrysotricha, Tabebuia heptaphylla, and Tipuana tipu. A total of 84 species are reported, from which 14 are recorded for the fi rst time in Paraná State and Flavoparmelia soredians is recorded for the fi rst time in Brazil. Parmeliaceae was the best represented family, with 45 species distributed in nine genera, followed by Physciaceae with 24 species in six genera. The native tree species showed greater lichen species richness and a higher number of exclusive lichen species than the exotic tree species. The highest lichen species richness was found in Tabebuia chrysotricha with 62 taxa, followed by Syagrus romanzoffi ana with 47. Candelaria concolor, Canoparmelia crozalsiana, Canoparmelia texana, Dirinaria applanata, Dirinaria confl uens, Heterodermia obscurata, Myelochroa lindmanii, Parmotrema pilosum, Physcia poncinsii, Punctelia borreri, Punctelia reddenda, Pyxine subcinerea, Ramalina celastri and Ramalina peruviana are suggested as macrolichen species with the greatest potential for future biomonitoring studies of air quality in Curitiba.

  11. Aspects of the Flora and Vegetation of the “Izvorul Bigar” Nature Reserve (South-Western Romania

    Alma L. NICOLIN

    2009-06-01

    Full Text Available The “Izvorul Bigăr” Nature Reserve is located in south-western Romania. The aim of the present paper is to describe some aspects of the flora and vegetation around Bigăr spring. The analysis of the vegetal association was carried out using the method of the Central-European phytocoenological school. The vegetation around the Bigăr spring and waterfall is dominated by compact beech forests with a frequently reduced grassy layer and soil rich in humus. On the banks of the watercourse and on the rocks around the spring there are species specific to flooding plains of the beech sub-stratum and also thermophilous and xerophilous species, many of them Balkan, Pontic or Mediterranean elements. The phytocoenoses we analysed belong to the Phyllitidi - Fagetum Vida (1959 1963 association. The association is characteristic to shady and moist slopes with soils rich in humus and formed on a lime substratum sometimes with surface rocks. The species with high abundance-dominance values are: Fagus sylvatica, Fraxinus ornus, Acer pseudoplatanus, Tilia cordata, Hedera helix, Asplenium scolopendrium, Arum orientale, Asarum europaeum, Cardamine bulbifera, Lunaria annua, Polypodium vulgare. Such species as Carpinus orientalis, Cotinus coggygria, Fraxinus ornus, Ruscus hypoglossum, Syringa vulgaris point out the thermophilous character of the forests in southern Banat.

  12. Aspects of the Flora and Vegetation of the “Izvorul Bigăr” Nature Reserve (South-Western Romania

    Ilinca M. IMBREA

    2009-06-01

    Full Text Available The “Izvorul Bigăr” Nature Reserve is located in south-western Romania. The aim of the present paper is to describe some aspects of the flora and vegetation around Bigăr spring. The analysis of the vegetal association was carried out using the method of the Central-European phytocoenological school. The vegetation around the Bigăr spring and waterfall is dominated by compact beech forests with a frequently reduced grassy layer and soil rich in humus. On the banks of the watercourse and on the rocks around the spring there are species specific to flooding plains of the beech sub-stratum and also thermophilous and xerophilous species, many of them Balkan, Pontic or Mediterranean elements. The phytocoenoses we analysed belong to the Phyllitidi - Fagetum Vida (1959 1963 association. The association is characteristic to shady and moist slopes with soils rich in humus and formed on a lime substratum sometimes with surface rocks. The species with high abundance-dominance values are: Fagus sylvatica, Fraxinus ornus, Acer pseudoplatanus, Tilia cordata, Hedera helix, Asplenium scolopendrium, Arum orientale, Asarum europaeum, Cardamine bulbifera, Lunaria annua, Polypodium vulgare. Such species as Carpinus orientalis, Cotinus coggygria, Fraxinus ornus, Ruscus hypoglossum, Syringa vulgaris point out the thermophilous character of the forests in southern Banat.

  13. A Review of the Characteristics of Small-Leaved Lime (Tilia cordata Mill. and Their Implications for Silviculture in a Changing Climate

    Tanguy De Jaegere

    2016-03-01

    Full Text Available Tilia cordata Mill. is a minor European broadleaved species with a wide but scattered distribution. Given its scarcity and low value in the wood market, it has received little attention from researchers and forest managers. This review summarizes the main aspects of T. cordata ecology and growth. Its main limiting factor is its need for warm summer temperatures to ensure successful seed production. It has a height growth pattern relatively similar to that of Acer pseudoplatanus L., with a slight delay in the early stages. Yield tables report great productivity, especially in eastern Europe. T. cordata used to be a major species in Europe, in contrast to its present distribution, but it is very likely to receive renewed interest in the future. Indeed, with the potential change of competition between species in some regions and the need for important diversification in others, T. cordata may play an important role in forest adaptation to climate change, especially owing to its wide ecological tolerance and its numerous ecosystem services. It is necessary to increase our knowledge about its regeneration and its responses to environmental and silvicultural factors, to establish clear management recommendations.

  14. Ecophysiological and seasonal variations in Cd, Pb, Zn, and Ni concentrations in the leaves of urban deciduous trees in Istanbul

    The concentrations of Cd, Pb, Zn and Ni were measured in the leaves of 7 species of deciduous trees, from the urban sites of Istanbul, in both the Spring and Autumn seasons. We detected some differences in the heavy metal concentrations of the control and urban site samples of identical species. Highest concentrations of Cd were detected in Populus, Pb in Aesculus and Robinia, Zn in Populus, and Ni in Robinia and Fraxinus. Lowest chlorophyll content and highest peroxidase (POD) activity was found in the urban site samples of Acer. We have found a positive correlation between the increase in the POD activity and the Pb concentration in Populus. Generally, the tree species investigated in this study, are considered to have different tolerance levels to heavy metal pollution. The data obtained show that the chlorophyll content and the POD activity may be used as heavy metal stress biomarkers in the urban trees. - Ecophysiological changes in the urban trees may be used as heavy metal stress biomarkers

  15. Soil characteristics and heavy metal accumulation by native plants in a Mn mining area of Guangxi, South China.

    Liu, Jie; Zhang, Xue-hong; Li, Tian-yu; Wu, Qing-xin; Jin, Zhen-jiang

    2014-04-01

    Revegetation and ecological restoration of a Mn mineland are important concerns in southern China. To determine the major constraints for revegetation and select suitable plants for phytorestoration, pedological and botanical characteristics of a Mn mine in Guangxi, southern China were investigated. All the soils were characterized by low pH and low nitrogen and phosphorus levels except for the control soil, suggesting that soil acidity and poor nutrition were disadvantageous to plant growth. In general, the studied mine soils had normal organic matter (OM) and cation exchange capacity (CEC). However, OM (8.9 g/kg) and CEC (7.15 cmol/kg) were very low in the soils from tailing dumps. The sandy texture and nutrient deficiency made it difficult to establish vegetation on tailing dumps. Mn and Cd concentrations in all soils and Cr and Zn concentrations in three soils exceeded the pollution threshold. Soil Mn and Cd were above phytotoxic levels, indicating that they were considered to be the major constraints for phytorestoration. A botanical survey of the mineland showed that 13 plant species grew on the mineland without obvious toxicity symptoms. High Mn and Cd concentrations have been found in the aerial parts of Polygonum pubescens, Celosia argentea, Camellia oleifera, and Solanum nigrum, which would be interesting for soil phytoremediation. Miscanthus floridulus, Erigeron acer, Eleusina indica, and Kummerowia striata showed high resistance to the heavy metal and harsh condition of the soils. These species could be well suited to restore local degraded land in a phytostabilization strategy. PMID:24271720

  16. Fine roots are the dominant source of recalcitrant plant litter in sugar maple-dominated northern hardwood forests.

    Xia, Mengxue; Talhelm, Alan F; Pregitzer, Kurt S

    2015-11-01

    Most studies of forest litter dynamics examine the biochemical characteristics and decomposition of leaf litter, but fine roots are also a large source of litter in forests. We quantified the concentrations of eight biochemical fractions and nitrogen (N) in leaf litter and fine roots at four sugar maple (Acer saccharum)-dominated hardwood forests in the north-central United States. We combined these results with litter production data to estimate ecosystem biochemical fluxes to soil. We also compared how leaf litter and fine root biochemistry responded to long-term simulated N deposition. Compared with leaf litter, fine roots contained 2.9-fold higher acid-insoluble fraction (AIF) and 2.3-fold more condensed tannins; both are relatively difficult to decompose. Comparatively, leaf litter had greater quantities of more labile components: nonstructural carbohydrates, cellulose and soluble phenolics. At an ecosystem scale, fine roots contributed over two-thirds of the fluxes of AIF and condensed tannins to soil. Fine root biochemistry was also less responsive than leaf litter to long-term simulated N deposition. Fine roots were the dominant source of difficult-to-decompose plant carbon fractions entering the soil at our four study sites. Based on our synthesis of the literature, this pattern appears to be widespread in boreal and temperate forests. PMID:26073624

  17. How fresh is maple syrup? Sugar maple trees mobilize carbon stored several years previously during early springtime sap-ascent.

    Muhr, Jan; Messier, Christian; Delagrange, Sylvain; Trumbore, Susan; Xu, Xiaomei; Hartmann, Henrik

    2016-03-01

    While trees store substantial amounts of nonstructural carbon (NSC) for later use, storage regulation and mobilization of stored NSC in long-lived organisms like trees are still not well understood. At two different sites with sugar maple (Acer saccharum), we investigated ascending sap (sugar concentration, δ(13) C, Δ(14) C) as the mobilized component of stored stem NSC during early springtime. Using the bomb-spike radiocarbon approach we were able to estimate the average time elapsed since the mobilized carbon (C) was originally fixed from the atmosphere and to infer the turnover time of stem storage. Sites differed in concentration dynamics and overall δ(13) C, indicating different growing conditions. The absence of temporal trends for δ(13) C and Δ(14) C indicated sugar mobilization from a well-mixed pool with average Δ(14) C consistent with a mean turnover time (TT) of three to five years for this pool, with only minor differences between the sites. Sugar maple trees hence appear well buffered against single or even several years of negative plant C balance from environmental stress such as drought or repeated defoliation by insects. Manipulative investigations (e.g. starvation via girdling) combined with Δ(14) C measurements of this mobilized storage pool will provide further new insights into tree storage regulation and functioning. PMID:26639654

  18. Insecticidal activities of bark, leaf and seed extracts of Zanthoxylum heitzii against the African malaria vector Anopheles gambiae.

    Overgaard, Hans J; Sirisopa, Patcharawan; Mikolo, Bertin; Malterud, Karl E; Wangensteen, Helle; Zou, Yuan-Feng; Paulsen, Berit S; Massamba, Daniel; Duchon, Stephane; Corbel, Vincent; Chandre, Fabrice

    2014-01-01

    The olon tree, Zanthoxylum heitzii (syn. Fagara heitzii) is commonly found in the central-west African forests. In the Republic of Congo (Congo-Brazzaville) its bark is anecdotally reported to provide human protection against fleas. Here we assess the insecticidal activities of Z. heitzii stem bark, seed and leaf extracts against Anopheles gambiae s.s, the main malaria vector in Africa. Extracts were obtained by Accelerated Solvent Extraction (ASE) using solvents of different polarity and by classical Soxhlet extraction using hexane as solvent. The insecticidal effects of the crude extracts were evaluated using topical applications of insecticides on mosquitoes of a susceptible reference strain (Kisumu [Kis]), a strain homozygous for the L1014F kdr mutation (kdrKis), and a strain homozygous for the G119S Ace1R allele (AcerKis). The insecticidal activities were measured using LD50 and LD95 and active extracts were characterized by NMR spectroscopy and HPLC chromatography. Results show that the ASE hexane stem bark extract was the most effective compound against An. gambiae (LD50 = 102 ng/mg female), but was not as effective as common synthetic insecticides. Overall, there was no significant difference between the responses of the three mosquito strains to Z. heitzii extracts, indicating no cross resistance with conventional pesticides. PMID:25525826

  19. Agricultural, domestic and handicraft folk uses of plants in the Tyrrhenian sector of Basilicata (Italy

    Guarrera Paolo

    2005-07-01

    Full Text Available Abstract Background Research was carried out into agricultural and domestic-handicraft uses in folk traditions in the Tyrrhenian sector of the Basilicata region (southern Italy, as it is typically representative of ethnobotanical applications in the Mediterranean area. From the point of view of furnishing a botanical support for the study of local "material culture" data was collected through field interviews of 49 informants, most of whom were farmers. Results The taxa cited are 60, belonging to 32 botanical families, of which 18 are employed for agricultural uses and 51 for domestic-handicraft folk uses. Data show a diffuse use of plants for many purposes, both in agricultural (present uses 14%; past uses 1% and for domestic-handicraft use (present uses 40%; past uses 45%; most of the latter are now in decline. Conclusion 60 data look uncommon or typical of the places studied. Some domestic-handicraft folk uses are typical of southern Italy (e.g. the use of Ampelodesmos mauritanicus for making ties, ropes, torches, baskets or that of Acer neapolitanum for several uses. Other uses (e.g. that of Inula viscosa and Calamintha nepeta for peculiar brooms, and of Origanum heracleoticum for dyeing wool red are previously unpublished.

  20. Corrosion Inhibition of Several Plant Leaves Extracts for Zinc in HCl Solution%几种植物叶提取物在HCl中对锌的缓蚀作用

    李向红; 付惠; 邓书; 刘建祥

    2010-01-01

    采用失重法首次研究了钓鱼慈竹(Neosinocalamus affinis)竹叶提取物(NALE),三角枫(Acer buergerianum)叶提取物(ABLE)和滇润楠(Machilus yunnanensis)叶提取物(MYLE)在盐酸中对锌的缓蚀作用.详细考察了缓蚀剂浓度(0.1~1.0g/L)、温度(30~60℃)、腐蚀浸泡时间(6~72 h)和盐酸浓度(0.01~0.05 mol/L)对缓蚀性能的影响.结果表明:三种植物提取物在0.01 mol/L HCl溶液中均对锌具有良好的缓蚀作用,且在锌表面的吸附符合Langmuir吸附等温式.缓蚀率随缓蚀剂浓度的增加而增大,但随温度、盐酸浓度和腐蚀浸泡时间的增加而减小.三种植物提取物的缓蚀率排序为:NALE>ABLE>MYLE.

  1. Multiscale model of a freeze-thaw process for tree sap exudation.

    Graf, Isabell; Ceseri, Maurizio; Stockie, John M

    2015-10-01

    Sap transport in trees has long fascinated scientists, and a vast literature exists on experimental and modelling studies of trees during the growing season when large negative stem pressures are generated by transpiration from leaves. Much less attention has been paid to winter months when trees are largely dormant but nonetheless continue to exhibit interesting flow behaviour. A prime example is sap exudation, which refers to the peculiar ability of sugar maple (Acer saccharum) and related species to generate positive stem pressure while in a leafless state. Experiments demonstrate that ambient temperatures must oscillate about the freezing point before significantly heightened stem pressures are observed, but the precise causes of exudation remain unresolved. The prevailing hypothesis attributes exudation to a physical process combining freeze-thaw and osmosis, which has some support from experimental studies but remains a subject of active debate. We address this knowledge gap by developing the first mathematical model for exudation, while also introducing several essential modifications to this hypothesis. We derive a multiscale model consisting of a nonlinear system of differential equations governing phase change and transport within wood cells, coupled to a suitably homogenized equation for temperature on the macroscale. Numerical simulations yield stem pressures that are consistent with experiments and provide convincing evidence that a purely physical mechanism is capable of capturing exudation. PMID:26400199

  2. A Study of Multi-Signal Monitoring System Establishment for Hemodynamic Energy Detection

    YeonSoo Shin

    2014-09-01

    Full Text Available Deaths due to cardiovascular diseases are increasing worldwide, and multi-signal monitoring systems to diagnose such diseases are under development. However, only a few researches are underway for devices that monitor hemodynamic energy, which is a marker for pulsatile flow generated by the contraction and relaxation of the heart. Therefore, this study aimed to integrate multiple monitoring devices into a single device, while also incorporating hemodynamic energy monitoring. Blood pressure and flow were measured with two channels each, while electrocardiogram (ECG, photoplethysmography (PPG, and temperature were measured with one channel each. All signals were processed at hardware level, and then converted into analog voltage. The seven signals were then converted into digital signals with a data acquisition board (DAQ. The software was developed with Labview™ (National Instruments, U.S.A to form a graphic user interface (GUI on a tablet computer (ACER, U.S.A through USB 2.0, to allow for monitoring and analysis of the signals obtained. Development of this system successfully formed a multi-signal monitoring system that integrates multiple signals into one device. Future directions include development of cardiovascular diagnosis algorithm and evaluation of the system via preclinical animal experiments.

  3. Habitat diversity of the Multicolored Asian ladybeetle Harmonia axyridis Pallas (Coleoptera: Coccinellidae in agricultural and arboreal ecosystems: a review

    Vandereycken, A.

    2012-01-01

    Full Text Available The Multicolored Asian ladybeetle, Harmonia axyridis (Pallas, native to Asia, is an invasive species in many European and American countries. Initially introduced as a biological control agent against aphids and coccids in greenhouses, this alien species rapidly invaded many habitats such as forests, meadows, wetlands, and agricultural crops. This paper reviews the habitats (forests, crops, herbs, gardens and orchards where H. axyridis has been observed, either during insect samplings or as part of Integrated Pest Management (IPM programs. Studies have referenced H. axyridis on 106 plant taxa (35 arboreal species, 21 crop species, 27 herbaceous species, 11 ornamental species, and 12 orchard species and have identified 89 plant-prey relationships (34 arboreal species, 16 crop species, 13 herbaceous species, 10 ornamental species, and 16 orchard species in different countries. Harmonia axyridis is more abundant in forest areas, principally on Acer, Salix, Tilia and Quercus, than in agroecosystems. Some plant species, such as Urtica dioica L., which surround crops, contain large numbers of H. axyridis and could constitute important reserves of this alien species in advance of aphid invasions into crops. This review highlights the polyphagy and eurytopic aspect of H. axyridis.

  4. Effects of heating and cooling rate on transformation behaviors in weld heat affected zone of low carbon steel; Teitanso koban no yosetsu netsu eikyobu no hentai kyodo ni oyobosu kanetsu reikyaku sokudo no eikyo

    Kanetsuki, Y.; Katsumata, M. [Kobe Steel, Ltd., Kobe (Japan)

    1998-01-25

    Discussions were given on effects of welding heat cycles on transformation behaviors in a weld heat affected zone (HAZ). Test pieces are low-carbon fine ferrite pearlite organization steel sheets, which have been treated with a thermomechanical control process (TMCP). The heat cycling was experimented at a maximum temperature of 1350 degC by using a high-frequency heating coil, heating rates from 0.15 to 200 degC/s, cooling rates from 10 to 80 degC/s at an elevated temperature region (higher than 900 degC), and transformation regions (lower than 900 degC) from 0.5 to 6 degC. A transformation curve in actual welding heat cycling was interpreted from these results. Shear-type inverse transformation (from ferrite to austenite) occurs in a rate region corresponding to the heating rate realized during welding. Austenite containing internal stress and a lower structure formed by this inverse transformation accelerates transformation into grain boundary ferrite (GBF) and acerous ferrite (AF). On the other hand, slow cooling in the elevated temperature region releases the internal stress, restores the lower structure, and suppresses the GBF and AF transformation. The GBF tends to precipitate pearlite in adjacent regions and deteriorates the HAZ tenacity. 17 refs., 8 figs., 1 tab.

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

    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

  6. Impact of Hot-Water Extraction on Acetone-Water Oxygen Delignification of Paulownia Spp. and Lignin Recovery

    Chen Gong

    2014-02-01

    Full Text Available A hardwood-based biorefinery process starting with hot-water extraction (HWE is recommended in order to remove most of the hemicelluloses/xylans before further processing. HWE may be followed by delignification in acetone/water in the presence of oxygen (AWO for the production of cellulose and lignin. In this study, the HWE-AWO sequence was evaluated for its effectiveness at removing lignin from the fast-growing species Paulownia tomentosa (PT and Paulownia elongata (PE, in comparison with the reference species, sugar maple (Acer saccharum, SM. HWE might lead to a remarkable increase in lignin accessibility, and as a result, a greater AWO delignification degree was observed for extracted PT, PE, and SM than for unextracted ones. Organosolv lignin was recovered from the spent liquor of AWO delignification of PT with/without prior HWE and characterized to evaluate the benefits of HWE on the lignin structure and purity. The lignin recovered from the spent liquor of HWE-AWO sequence is of higher purity and lighter color than that recovered from the AWO spent liquor. These properties along with low sulfur content are desirable for lignin high-value applications.

  7. Possibilities of cultivating ornamental trees and shrubs under conditions of air pollution with oxides of sulfur

    Bialobok, S.; Bartkowiak, S.; Rachwal, L.

    1974-01-01

    The field work conducted has shown that high concentrations of SO/sub 2/ in the air can be withstood by the following trees and shrubs. Trees: Acer campestris, A. platanoides, Ailanthus altissima, Aesculus hippocastanum, Morus alba, Platanus acerifolia, Pinus strobur, P. nigra, Populus Berolinensis, P. candicans, P. Hybr. 27, P. Marilandica, P. simonii, P. Serotina, Quercus robus, Robinia pseudoacacia. Shrubs: Caragana arborescens, Crataegus oxyacantha, C. monogyna, Cerasus mehaleb, Forsythia/most of the species and varieties/, Ligustrum vulgare, Philadelphus coronaria, Ptelea trifoliata, Sambucus nigra, Salix caprea, Sorbaria sorbifolia, Sorbus aucuparia, Taxus baccata. For the selection of trees and shrubs in the laboratory, high concentrations of SO/sub 2/ were used (60-150 ppm for a period of 10 minutes). Experiments were conducted on cut shrubs kept in the gas chambers. In order to estimate the degree of their injury, they were transferred to a shaded greenhouse. A concentration of 65 ppm of SO/sub 2/ could be withstood by the following Forsythias: Forsythia intermedia Primulina, F. Densiflora, F. Spectabilis, F. giraldina, F. suspensa, F. koreana, F. ovata, F. japonica and Hippophae rhamnoides. A concentration of 130 ppm could be withstood only by F. intermedia Vitelina. A similarly high concentration of SO/sub 2/ could be withstood by shoots and leaves of Ailanthus girladii Duclouxii and by Platanus acerifolia. From among the lilacs Syringa pekinensis and S. amurensis proved resistant to high concentrations of SO/sub 2/.

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

    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.

  9. Physical and chemical properties of some imported woods and their degradation by termites.

    Shanbhag, Rashmi R; Sundararaj, R

    2013-01-01

    The influence of physical and chemical properties of 20 species of imported wood on degradation of the wood by termites under field conditions was studied. The wood species studied were: Sycamore maple, Acer pseudoplatanus L. (Sapindales: Sapindaceae) (from two countries), Camphor, Dryobalanops aromatic C.F.Gaertner (Malvales: Dipterocarpaceae), Beech, Fagus grandifolia Ehrhart (Fagales: Fagaceae), F. sylvatica L. (from two countries), Oak, Quercus robur L., Ash, Fraxinus angustifolia Vahl (Lamiales: Oleaceae), F. excelsior L., Padauk, Pterocarpus soyauxii Taubert (Fabales: Fabaceae), (from two countries), Jamba, Xylia dolabrifiormis Roxburgh, Shorea laevis Ridley (Malvales: Dipterocarpaceae), S. macoptera Dyer, S. robusta Roth, Teak, Tectona grandis L.f. (Lamiales: Lamiaceae) (from five countries), and rubber tree, Hevea brasiliensis Müller Argoviensis (Malpighiales: Euphorbiaceae) from India. The termites present were: Odontotermes horni (Wasmann) (Isoptera: Termitidae), O. feae, O. wallonensis, and O. obeus (Rambur). A significant conelation was found between density, cellulose, lignin, and total phenolic contents of the wood and degradation by termites. The higher the density of the wood, the lower the degradation. Similarly, higher amount of lignin and total phenolic contents ensured higher resistance, whereas cellulose drives the termites towards the wood. PMID:23906349

  10. Potential New Associations of North American Parasitoids With the Invasive Asian Longhorned Beetle (Coleoptera: Cerambycidae) for Biological Control.

    Duan, Jian J; Aparicio, Ellen; Tatman, Daria; Smith, Michael T; Luster, Doug G

    2016-04-01

    The Asian longhorned beetle, Anoplophora glabripennis (Motschulsky), is a polyphagous wood-boring insect native to Asia. Since it invaded North America in the 1990s, the beetle has been continuously targeted by quarantines and eradication programs in the United States and Canada. We examined the potential for development of new species-associations between A. glabripennis and hymenopteran parasitoids collected from cerambycids and other wood-boring insects infesting red maple (Acer rubrum L.) trees in the mid-Atlantic region of the United States. Results of our study showed that five groups of braconid parasitoids (Ontsira mellipes Ashmead, Rhoptrocentrus piceus Marsh, Spathius laflammei Provancher, Heterospilus spp., and Atanycolus spp.) successfully attacked early instars of A. glabripennis larvae infesting red maple logs and produced both male and female progenies. One species, O. mellipes, was continuously reared on A. glabripennis larvae inserted inside small red maple sticks for over 50 generations, and produced female-biased progeny (∼6:1 female to male ratio) at each generation. Continuous rearing of O. mellipes on A. glabripennis larvae did not significantly increase the parasitism and mean number of progeny produced per parasitized host. Together, these findings demonstrate that some North American parasitoids may be able to develop new associations with A. glabripennis and thus should be further studied under semifield or field conditions for possible use in biocontrol. PMID:26602779

  11. Establishing trees on cut-over peatlands in eastern Canada

    J. Bussières

    2008-12-01

    Full Text Available Four major tree-planting trials on cut-over peatlands in eastern Canada were surveyed in 2002, in order to evaluate the potential use of trees in rehabilitation following horticultural peat extraction. At one of the sites, an experiment to determine the appropriate fertilisation rate for trees planted on cut-over peatlands was also conducted over several years. Tree performance was assessed by measuring survival, total height and annual growth of red maple (Acer rubrum L., tamarack (Larix laricina (Du Roi Koch., black spruce (Picea mariana (Mill. B.S.P., jack pine (Pinus banksiana Lamb. and hybrid poplar (Populus spp.. Establishment and growth of tamarack and black spruce in cut-over peatlands showed good potential when compared to performance in conventional forestry plantations. Red maple and jack pine gave poor productivity but promising survival, whilst hybrid poplar plantings failed. Adding nutrients was essential for growth but dosages above 122.5 g of 3.4N-8.3P-24.2K per tree gave no further improvement. Therefore, several different tree species can be planted to reclaim cut-over peatlands in eastern Canada, so long as the appropriate species are chosen and nutrients are provided.

  12. Dynamics of nitrogen nutrition of coexisting dominant trees in mixed broad-leaved/Korean pine forest

    Li Yuwen

    1999-01-01

    Chemical analysis of ammonium, nitrate and total nitrogen in tree leaves and roots and an in-vivo bioassay for nitrate reductase activity (NRA) were used to monitor the seasonal variations in nitrogen assimilation among four coexisting dominant tree species, including Pinus koraiensis, Ti/ia amurensis, Fraxinus mandshurica and Acer mono, in a virgin mixed broad-leaved/Korean pine (Pinus koraiensis) forest. The soil study included individual horizons of L+F (0-5 cm), Ah (5-11 cm) and Aw (11-25 cm). All four species had nitrate and ammonium in their roots and leaves, and also NRA in leaves. This indicated that these coexisting species were adapted to ammonium + nitrate nutrition. A negative correlation existed between nitrate use and ammonium use. Ammonium concentration was higher than that of nitrate in tree leaves and roots, and also in soils, which indicated climax woody species had a relative preference for ammonium nutrition. There was a positive relationship between tree nitrogen nutrition use and soil nitrogen nutrient supply. Utilization of ammonium and nitrate as well as the seasonal patterns differed significantly between the species. Peaks of ammonium, nitrate, NRA and total nitrogen in one species were therefore not necessarily synchronous with peaks in other species, and which indicated a species-specific seasonal use of nitrogen. The species-specific temporal differentiation in nitrogen use might reduce the competition between co-existing species and may be an important mechanism promoting stability of virgin mixed broad-leaved∥Korean pine forest.

  13. Variation of Soil Nutrition in a Fagus engleriana Seem.-Cyclobalanopsis oxyodon Oerst. Community Over a Small Scale in the Shennongjia Area, China

    2006-01-01

    Soil nutrition is a key factor influencing species composition in a community, but it has clearly scaledependent heterogeneity. In the present study, geostatistics methods and canonical correspondence analysis (CCA) were used to detect: (i) the variation range of soil spatial heterogeneity; (ii) the influence of topographic factors on the distribution of soil nutrition; and (iii) the relationships between soil chemical properties and species in the community. In all, 23 soil variables were measured, including total N and organic C, Al, Ba, Ca, Cr, Cu, Fe, Ga, Li, Mg, Mn, Na, NH4-N, Ni, NO3-N, Pb, pH, P, Sr, Ti, V, and Zn. Semi-variograms of these variables were calculated and mapped. All indices showed autocorrelations, with ranges between 29 and 200 m. When the sample method was larger than these distances, spatial autocorrelations were avoided. The distribution patterns of Ca, Cr, Ga, K, Mg, organic C, P, Pb, and pH, and total N were related to the microtopography and the distribution of these compounds was clumped in water catchments area. The CCA method was used to investigate the relationship between plant species and soil properties in this community. Fagus engleriana Seem., Lindera obtusiloba BI. Mus., and Acer griseum (Franch.) Pax were correlated with organic C, available N, and P.

  14. Factors affecting soil fauna feeding activity in a fragmented lowland temperate deciduous woodland.

    Simpson, Jake E; Slade, Eleanor; Riutta, Terhi; Taylor, Michele E

    2012-01-01

    British temperate broadleaf woodlands have been widely fragmented since the advent of modern agriculture and development. As a result, a higher proportion of woodland area is now subject to edge effects which can alter the efficiency of ecosystem functions. These areas are particularly sensitive to drought. Decomposition of detritus and nutrient cycling are driven by soil microbe and fauna coactivity. The bait lamina assay was used to assess soil fauna trophic activity in the upper soil horizons at five sites in Wytham Woods, Oxfordshire: two edge, two intermediate and one core site. Faunal trophic activity was highest in the core of the woodland, and lowest at the edge, which was correlated with a decreasing soil moisture gradient. The efficiency of the assay was tested using four different bait flavours: standardised, ash (Fraxinus excelsior L.), oak (Quercus robur L.), and sycamore (Acer pseudoplatanus L.). The standardised bait proved the most efficient flavour in terms of feeding activity. This study suggests that decomposition and nutrient cycling may be compromised in many of the UK's small, fragmented woodlands in the event of drought or climate change. PMID:22235311

  15. Urban tree effects on soil organic carbon.

    Jill L Edmondson

    Full Text Available Urban trees sequester carbon into biomass and provide many ecosystem service benefits aboveground leading to worldwide tree planting schemes. Since soils hold ∼75% of ecosystem organic carbon, understanding the effect of urban trees on soil organic carbon (SOC and soil properties that underpin belowground ecosystem services is vital. We use an observational study to investigate effects of three important tree genera and mixed-species woodlands on soil properties (to 1 m depth compared to adjacent urban grasslands. Aboveground biomass and belowground ecosystem service provision by urban trees are found not to be directly coupled. Indeed, SOC enhancement relative to urban grasslands is genus-specific being highest under Fraxinus excelsior and Acer spp., but similar to grasslands under Quercus robur and mixed woodland. Tree cover type does not influence soil bulk density or C∶N ratio, properties which indicate the ability of soils to provide regulating ecosystem services such as nutrient cycling and flood mitigation. The trends observed in this study suggest that genus selection is important to maximise long-term SOC storage under urban trees, but emerging threats from genus-specific pathogens must also be considered.

  16. Urban tree effects on soil organic carbon.

    Edmondson, Jill L; O'Sullivan, Odhran S; Inger, Richard; Potter, Jonathan; McHugh, Nicola; Gaston, Kevin J; Leake, Jonathan R

    2014-01-01

    Urban trees sequester carbon into biomass and provide many ecosystem service benefits aboveground leading to worldwide tree planting schemes. Since soils hold ∼75% of ecosystem organic carbon, understanding the effect of urban trees on soil organic carbon (SOC) and soil properties that underpin belowground ecosystem services is vital. We use an observational study to investigate effects of three important tree genera and mixed-species woodlands on soil properties (to 1 m depth) compared to adjacent urban grasslands. Aboveground biomass and belowground ecosystem service provision by urban trees are found not to be directly coupled. Indeed, SOC enhancement relative to urban grasslands is genus-specific being highest under Fraxinus excelsior and Acer spp., but similar to grasslands under Quercus robur and mixed woodland. Tree cover type does not influence soil bulk density or C∶N ratio, properties which indicate the ability of soils to provide regulating ecosystem services such as nutrient cycling and flood mitigation. The trends observed in this study suggest that genus selection is important to maximise long-term SOC storage under urban trees, but emerging threats from genus-specific pathogens must also be considered. PMID:25003872

  17. Suitability of thermoluminescence, chemiluminescence, ESR and viscosity measurements as detection method for the irradiation of medicinal herbs

    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.)

  18. New, rare or remarkable microfungi in the Italian Alps (Carnic Alps)--part I--ascomycotina.

    Feige, G B; Ale-Agha, N; Jensen, M; Christiaans, B; Kricke, R

    2004-01-01

    During our observations in the SE part of the Carnic Alps in the year 2003 we were able to collect and identify 35 ascomycetes on trees and dead wood. Among these one can find numerous ascomycetes of different orders e.g. Pyrenomycetes, Loculoascomycetes and Discomycetes. Some species like Botryosphaeria ribis GROSENLUCHER & DUGGAR on Ribes alpinum L., Dothiora pyrenophora (FR.) FR. on Sorbus aucuparia L., Gemmamyces piceae (BORTH.) CASAGO. on Picea excelsa (LAM.) LINK, Glomerella montana (SACC.) v. ARX & E. MULLER on Sesleria caerulea (L.) ARD, Hymenoscyphus immutabilis (Fuck.) Dennis on Alnus incana (L.) Moench, Hysterographium fraxini (PERS. Ex. FR.) de Not. on Fraxinus ornus L., Lachnellula willkommii (Hartig) DENNIS [= Trichascyphella willkommii (Hartig) NANNF.] on Larix decidua MILL.,Leptosphaeria lycopodina (Mont.) SACC. on Lycopodium annotinum L., Mollisia adenostylidis REHM. on Adenostyles glabra (MILL.) DC., Pezicula cinnamomea (DC.)SACC. [ana: Cryptosporiopsis quercina PETRAK] on Quercus robur L., Pyrenopeziza petiolaris (A. & S. Ex FR.) NANNF. on Acer pseudoplatanus L., Tapesia rosae (PERS.) FUCKEL on Rosa canina L., are new for this area. All specimen are deposited in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha. PMID:15756826

  19. Soil acidification and foliar nutrient status of Ontario's deciduous forest in 1986 and 2005

    To assess the impacts of the decline in sulphur (S) deposition over the past 20 years in Ontario, soil chemistry and sugar maple (Acer saccharum Marsh) foliar chemistry were measured at 17 sites in south and central Ontario in 2005 and compared with archived samples collected in 1986. Foliar S concentrations were lower in 2005, reflecting the decline in S deposition whereas foliar N remained unchanged, reflecting the lack of change in N deposition in Ontario. Mineral soil pH, exchangeable base cations were lower in 2005 whereas total S, N and cation exchange capacity (CEC) were unchanged. Foliar concentrations of Ca were positively related to soil Ca levels in the A-horizon and were lower in 2005. Despite evidence of increasing soil acidity and losses of calcium, foliar base cation concentrations at most sites were adequate for sugar maple and forest health in terms of canopy appearance (Decline Index) improved. - Despite declining S deposition soils acidified in deciduous forests of Ontario between 1986 and 2005, while crown condition improved

  20. Arboriculture for quality timber production with hardwood: results after 20 years from planting

    Barreca L

    2010-12-01

    Full Text Available In the last decades, production forestry plantations has been developed using typical forest tree species, or species of agricultural interest, such as walnut and cherry. The use of these species in a context different than the traditional one put a number of problems not easy to solve. The present study has considered some timber-quality plantations of hardwoods species (Acer pseudoplatanus L., Prunus avium L., Fraxinus excelsior L., Juglans regia L. established on the Serre Catanzaresi (VV, with the aim of assessing the achievements obtained both in quantitative (growth and qualitative (shape of the stems, degree of branching terms. The results of the analyses carried out revealed that the studied plantations are an interesting example of possibilities and limits of cultivation of commonly used hardwoods in relation to the practices adopted. The observed differences are mainly related to the different species used. Some of them (sycamore and wild cherry guaranteed satisfactory results, others (ash and walnut showed severe limitations, due to the poor quality of planting material, the incompatibility between the species needs and site characteristics, or because these species usually constitute mixed populations.

  1. THE COPĂCEL HILL FOREST, BETWEEN BĂLA AND ERCEA, A FUTURE RESERVE OF MUREŞ COUNTY

    OROIAN SILVIA

    2012-12-01

    Full Text Available The forest lies in the region known as the “Transylvanian Plain”, on the Copăcel hill, between Băla and Ercea. The specific landscape of this region is characterized by medium altitude hills, with wide and soft slopes. In this forest, the presence of the Delphinium simonkaianum Pawł. var. psilocarpum (Simk. Pawł species, a threatened endemic taxon, was reported in 1953. In 2011, this globally threatened taxon was identified, after 58 years, on the upper side of the Copăcel slope, in a mixed oak and hornbeam forest. These oak and hornbeam mixtures are the result of impacts exerted on oak forests. The identified association, Melampyro bihariensis-Carpinetum (Borza 1941 Soó 1964 em. Coldea 1975, has three distinct layers: the arborescent layer dominated by Carpinus betulus and Quercus petraea, along with Quercus robur, Prunus avium, Acer campestre, Ulmus glabra, etc., with good canopy cover (0.8-0.9; the shrub layer, represented by species such as: Crataegus monogyna, Corylus avellana, Cornus mas, Ligustrum vulgare, Rosa canina, Sambucus nigra, Staphylea pinnata, etc., is relatively poor in individuals, which are present particularly in forest clearings or at the edge of the forest. Grass synusia is well developed, sometimes forming an almost continuous cover (Asarum europaeum, Convallaria majalis, Dactylis glomerata ssp. aschersoniana, Galium odoratum, Melampyrum bihariense, Stellaria holostea, Aconitum anthora, Aconitum moldavicum, Lilium martagon, Arum orientale.

  2. Geoarchaeological investigations at Sormás-Török-földek, in Southwestern Transdanubia, Hungary

    Katalin NÁFRÁDI

    2014-11-01

    Full Text Available A comprehensive and detailed picture was gained about the historical events and the natural environment of Southwestern Hungary at the beginning of the 5th millennia BC. Wood charcoal analysis provided site-related information about the natural milieu of the site. Anthracological analysis has not been carried out in Southwestern Hungary so far, whereby more than 3600 fragments of charred wood remains were identified. Our dataset was compared to pollen analytical, archaeobotanical and archaeological data to create a more accurate vegetation picture for this period of time and to reconstruct the utilization of wood during Middle and Late Neolithic.Charcoal assemblage reflects the composition of the woodland around the site. Based on the results a thermophilous Quercus forest mixed with Fagus, Fraxinus, Acer, Alnus and Ulmus existed in the study site during the Middle and Late Neolithic and different types of wood were used for fire wood and for construction purposes as well. Anthracological analysis of samples from Sormás-Török-földek enabled a more accurate vegetation reconstruction for the study site by the comparison to previously known pollen analytical data and added extra information regarding the local vegetation and wood utilization for the Middle and Late Neolithic.

  3. Comparative behavior of three long-lived radionuclides in forest ecosystems

    This paper deals with studies in three forest ecosystems in eastern Tennessee, an area of rich temperate deciduous forests, sometimes referred to as mixed mesophytic forests. Two of these forest ecosystems were contaminated as a result of waste disposal operations. The third was experimentally tagged with millicurie quantities of 137Cs. One of these ecosystems is a floodplain forest that is typical of this region. This forest has been growing on alluvial soils since 1944. Prior to that time the area was a temporary holding pond within White Oak Creek which received radioactive effluents from ORNL. Radiocesium was deposited in the pond sediments as were 90Sr, 239Pu, 241Am, and other radionuclides. The dam which created the pond failed in late 1944, and the area was allowed to revert to natural conditions. The result was the development of a floodplain forest consisting of three different forest communities. The soils are fertile alluvials representative of bottomlands. The overstory tree species are principally ash, sycamore, boxelder, willow, and sweetgum (Fraxinus americana L., Plantanus occidentalis L., Acer negundo L., Salix nigra Marsh, and Liquidambar styraciflua L., respectively)

  4. Evaluation of radiocesium concentrations in new leaves of wild plants two years after the Fukushima Dai-ichi Nuclear Power Plant accident.

    Sugiura, Yuki; Shibata, Michihiro; Ogata, Yoshimune; Ozawa, Hajime; Kanasashi, Tsutomu; Takenaka, Chisato

    2016-08-01

    Radiocesium ((137)Cs) transfer to plants immediately after the Fukushima Dai-ichi Nuclear Power Plant accident was investigated by collecting newly emerged leaf and soil samples between May 2011 and November 2012 from 20 sites in the Fukushima prefecture. Radiocesium concentrations in leaf and soil samples were measured to calculate concentration ratios (CR). Woody plants exhibited high CR values because (137)Cs deposited on stems and/or leaves were transferred to newly emerging tissues. The CR values in 2012 declined as compared to that in 2011. Exchangeable (137)Cs rates in soil (extraction rate) samples were measured at five sites. These rates decreased at four sites in 2012 and depended on environmental conditions and soil type. Both CR values and extraction rates decreased in 2012. However, CR values reflected the changes in extraction rates and characteristics of each species. Amaranthaceae, Chenopodiaceae, and Polygonaceae, which had been identified as Cs accumulators, presented no clear (137)Cs accumulation ability. In 2012, the perennial plant Houttuynia cordata and deciduous trees Chengiopanax sciadophylloides and Acer crataegifolium displayed high CR values, indicating that these species are (137)Cs accumulators and may be considered as potential species for phytoremediation. PMID:27116401

  5. Natural and experimental tests of trophic cascades: gray wolves and white-tailed deer in a Great Lakes forest.

    Flagel, D G; Belovsky, G E; Beyer, D E

    2016-04-01

    Herbivores can be major drivers of environmental change, altering plant community structure and changing biodiversity through the amount and species of plants consumed. If natural predators can reduce herbivore numbers and/or alter herbivore foraging behavior, then predators may reduce herbivory on sensitive plants, and a trophic cascade will emerge. We have investigated whether gray wolves (Canis lupus) generate such trophic cascades by reducing white-tailed deer (Odocoileus virginianus) herbivory on saplings and rare forbs in a northern mesic forest (Land O' Lakes, WI). Our investigation used an experimental system of deer exclosures in areas of high and low wolf use that allowed us to examine the role that wolf predation may play in reducing deer herbivory through direct reduction in deer numbers or indirectly through changing deer behavior. We found that in areas of high wolf use, deer were 62 % less dense, visit duration was reduced by 82 %, and percentage of time spent foraging was reduced by 43 %; in addition, the proportion of saplings browsed was nearly sevenfold less. Average maple (Acer spp.) sapling height and forb species richness increased 137 and 117 % in areas of high versus low wolf use, respectively. The results of the exclosure experiments revealed that the negative impacts of deer on sapling growth and forb species richness became negligible in high wolf use areas. We conclude that wolves are likely generating trophic cascades which benefit maples and rare forbs through trait-mediated effects on deer herbivory, not through direct predation kills. PMID:26670677

  6. ACRR [Annular Core Research Reactor] fission product release tests: ST-1 and ST-2

    Two experiments (ST-1 and ST-2) have been performed in the Annular Core Research Reactor (ACER) at Sandia National Laboratories (SNLA) to obtain time-resolved data on the release of fission products from irradiated fuels under light water reactor (LWR) severe accident conditions. Both experiments were conducted in a highly reducing environment at maximum fuel temperatures of greater than 2400 K. These experiments were designed specifically to investigate the effect of increased total pressure on fission product release; ST-1 was performed at approximately 0.16 MPa and ST-2 was run at 1.9 MPa, whereas other parameters were matched as closely as possible. Release rate data were measured for Cs, I, Ba, Sr, Eu, Te, and U. The release rates were higher than predicted by existing codes for Ba, Sr, Eu, and U. Te release was very low, but Te did not appear to be sequestered by the zircaloy cladding; it was evenly distributed in the fuel. In addition, in posttest analysis a unique fuel morphology (fuel swelling) was observed which may have enhanced fission product release, especially in the high pressure test (ST-2). These data are compared with analytical results from the CORSOR correlation and the VICTORIA computer model. 8 refs., 8 figs., 2 tabs

  7. The role of selected tree species in industrial sewage sludge/flotation tailing management.

    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

  8. Response of seedlings of different tree species to elevated C02 in Changbai Mountain

    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.

  9. Analysis of airborne pollen grains in Konya, Turkey, 2005

    In this study, airborne pollen grains of Konya province were investigated using Durham sampler from January to December 2005. A total of 4420 pollen grains/cm/sup 2/ which belonged to 29 taxa and 9 unidentified pollen grains were recorded. From identified taxa, 19 belong to arboreal and 10 taxa to non-arboreal plants. Total pollen grains consist of 87,49% arboreal, 12,31% non-arboreal plants and 0,20% unidentified pollen grains. In the investigated region, from arboreal plant taxa Pinus spp. (21,63%), Fraxinus spp. (21,13%), Cupressaceae (15,84%), Ailanthus spp. (7,47%), Platanus spp. (3,80%), Acer spp. (3,28%), Populus spp. (1,86%), Sophora spp. (3,85%) and from non-arboreal plant taxa Chenopodiaceae / Amaranthaceae (4,77%), Poaceae (3,67%) were responsible for the greatest amount of pollen. During the study period, the pollen fall reached its highest level in March. (author)

  10. Forest structure and woody plant species composition after a wildfire in beech forests in the north of Iran

    Mohammad Naghi Adel; Hassan Pourbabaei; Ali Omidi; Daniel C Dey

    2013-01-01

    Beech (Fagus orientalis Lipsky) forest covers about 565,000 ha of land in Guilan province,north of Iran and forms a major carbon pool.It is an important economic,soil protection and recreation resource.We studied long-term effects of fire on the structure and composition 37 years after fire occurrence in these forests.To do this research,we selected 85 ha burned and 85 ha unbumed beech forests).The results indicated that the fire had not changed the overall uneven-aged structure,but it changed forest composition from pure stands to mixed stands that now include species such as Carpinus betulus,Acer cappadocicum and Alnus subcordata.The density of trees and regeneration was significantly increased,while the density of shrubs significantly decreased.The main reasons for increased tree regeneration were attributed to (1) reduction of litter depth,and (2) increase in available light from opening of the canopy and reduction in shrub competition.It is apparent that the forest is on a path to return to its natural state before the fire after 37 years.

  11. Effects of elevated ozone on CO2 uptake and leaf structure in sugar maple under two light environments

    The interactive effects of ozone and light on leaf structure, carbon dioxide uptake and short-term carbon allocation of sugar maple (Acer saccharum Marsh.) seedlings were examined using gas exchange measurements and 14C-macroautoradiographic techniques. Two-year-old sugar maple seedlings were fumigated from budbreak for 5 months with ambient or 3 × ambient ozone in open-top chambers, receiving either 35% (high light) or 15% (low light) of full sunlight. Ozone accelerated leaf senescence, and reduced net photosynthesis, 14CO2 uptake and stomatal conductance, with the effects being most pronounced under low light. The proportion of intercellular space increased in leaves of seedlings grown under elevated ozone and low light, possibly enhancing the susceptibility of mesophyll cells to ozone by increasing the cumulative dose per mesophyll cell. Indeed, damage to spongy mesophyll cells in the elevated ozone × low light treatment was especially frequent. 14C macroautoradioraphy revealed heterogeneous uptake of 14CO2 in well defined areole regions, suggesting patchy stomatal behaviour in all treatments. However, in seedlings grown under elevated ozone and low light, the highest 14CO2 uptake occurred along larger veins, while interveinal regions exhibited little or no uptake. Although visible symptoms of ozone injury were not apparent in these seedlings, the cellular damage, reduced photosynthetic rates and reduced whole-leaf chlorophyll levels corroborate the visual scaling of whole-plant senescence, suggesting that the ozone × low light treatment accelerated senescence or senescence-like injury in sugar maple. (author)

  12. Decomposition and nitrogen dynamics of 15N-labeled leaf, root, and twig litter in temperate coniferous forests

    van Huysen, Tiff L.; Harmon, Mark E.; Perakis, Steven S.; Chen, Hua

    2013-01-01

    Litter nutrient dynamics contribute significantly to biogeochemical cycling in forest ecosystems. We examined how site environment and initial substrate quality influence decomposition and nitrogen (N) dynamics of multiple litter types. A 2.5-year decomposition study was installed in the Oregon Coast Range and West Cascades using 15N-labeled litter from Acer macrophyllum, Picea sitchensis, and Pseudotsuga menziesii. Mass loss for leaf litter was similar between the two sites, while root and twig litter exhibited greater mass loss in the Coast Range. Mass loss was greatest from leaves and roots, and species differences in mass loss were more prominent in the Coast Range. All litter types and species mineralized N early in the decomposition process; only A. macrophyllum leaves exhibited a net N immobilization phase. There were no site differences with respect to litter N dynamics despite differences in site N availability, and litter N mineralization patterns were species-specific. For multiple litter × species combinations, the difference between gross and net N mineralization was significant, and gross mineralization was 7–20 % greater than net mineralization. The mineralization results suggest that initial litter chemistry may be an important driver of litter N dynamics. Our study demonstrates that greater amounts of N are cycling through these systems than may be quantified by only measuring net mineralization and challenges current leaf-based biogeochemical theory regarding patterns of N immobilization and mineralization.

  13. Effect of enhanced UV-B radiation of adaxial leaf surface micromorphology and epicuticular wax biosynthesis of sugar maple

    Sugar maple (Acer saccharum [Marsh.]) seedlings were exposed to UV-BBE ranging from 0.61 kJ m-2 d-1 to 12.48 kJ m-2 d-1. Increasing UV-B intensity was associated with changes in micromorphological characteristics of the adaxial leaf surface. In vivo incorporation of [1-14C] acetate into sugar maple adaxial leaf surface epicuticular wax indicated (p<0.05) a UV-B sensitivity threshold at or near 6.2 kJ m-2 d-1. Exposure to dosages greater than 6.2 kJ m-2 d-1 resulted in a significant (p<0.05) decrease in wax biosynthesis. The proportion of [1-14C] acetate incorporated into each of the different epicuticular wax classes changed with increasing UV-B. Incorporation of [1-14C] acetate into alkyl esters decreased while incorporation into alkanes increased with increasing UV-B dose. The effects of enhanced UV-B dose recorded in this experiment may have implications for cuticle function. (author)

  14. Response of a forest ecotone to ionizing radiation. Progress report, October 15, 1978-October 14, 1979

    Compositional and structural characteristics of three forest types, including aspen dominated, maple-birch dominated, and an intervening ecotone, were studied before and after irradiation in northern Wisconsin. Irradiation occurred during the summer of 1972. As of the summer of 1978, establishment of tree seedlings at 10 m from the radiation source continued to be inhibited by the vigorous development of ground vegetation except, in part, in the aspen area where seedling density increased sharply relative to 1977 because of an influx of Acer rubrum. By 1974 many of the seedlings at 20 m had reached the sapling size-class. At the present time it appears that recolonization of the 10 m irradiated zone by the original tree flora will be a very slow process, largely because of a dense growth of Rubus sp. and other heliophytes. As of 1978 the recovery of leaf litter production appeared to be continuing in all three areas although the ratios of tree to shrub litter were still well below preirradiation levels at 10 m and slightly below at 20 m. In most respects, the ecotone has shown properties and responses to radiation intermediate to those observed in the aspen and maple-birch areas. The rate and compositional characteristics of succession in the ecotone relative to aspen and maple-birch forest types is presently under study

  15. Tree species composition affects the abundance of rowan (Sorbus aucuparia L.) in urban forests in Finland.

    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

  16. Thermal neutron scattering data for the moderator materials H2O, D2O and ZrHx in ENDF-6 format and as ACE library for MCNP(X) codes

    At thermal neutron energies, the binding of the scattering nucleus in a solid, liquid, or gas affects the cross section and the angular and energy distributions of the scattered neutrons. These effects are described in the thermal sub-library of evaluated files in File 7 of the ENDF- 6 format. New and re-evaluations are described for the three thermal moderator materials: hydrogen bound in light water (H2O), deuterium bound in heavy water (D2O) and hydrogen in ZrH (zirconium hydride). The calculations for a variety of temperatures were made with the LEAPR module of NJOY to obtain new evaluated thermal neutron scattering files that are accurate over a wider range of energy and momentum transfer than existing files. The IKE physics models are described in detail, and the inputs to LEAPR are given. Detailed comparisons with a significant number of measurements of differential and integral neutron cross sections and other relevant data are reported (for the validation of the generated Scattering Law data files S(α,β,Τ)). Experimental data are reproduced reasonably well. In addition, thermal MCNP data sets for use in the continuous Monte Carlo codes MCNP and MCNPX were generated from these evaluations. Calculated neutron spectra agree rather well with measurements. Details are also given of the updates to the NJOY modules LEAPR, THERMR, and ACER necessary in generating and processing the thermal neutron scattering data. (author)

  17. Three-dimensional mapping of light transmittance and foliage distribution using lidar

    The horizontal and vertical distributions of light transmittance were evaluated as a function of foliage distribution using lidar (light detection and ranging) observations for a sugar maple (Acer saccharum) stand in the Turkey Lakes Watershed. Along the vertical profile of vegetation, horizontal slices of probability of light transmittance were derived from an Optech ALTM 1225 instrument's return pulses (two discrete, 15-cm diameter returns) using indicator kriging. These predictions were compared with (i) below canopy (1-cm spatial resolution) transect measurements of the fraction of photosynthetically active radiation (FPAR) and (ii) measurements of tree height. A first-order trend was initially removed from the lidar returns. The vertical distribution of vegetation height was then sliced into nine percentiles and indicator variograms were fitted to them. Variogram parameters were found to vary as a function of foliage height above ground. In this paper, we show that the relationship between ground measurements of FPAR and kriged estimates of vegetation cover becomes stronger and tighter at coarser spatial resolutions. Three-dimensional maps of foliage distribution were computed as stacks of the percentile probability surfaces. These probability surfaces showed correspondence with individual tree-based observations and provided a much more detailed characterization of quasi-continuous foliage distribution. These results suggest that discrete-return lidar provides a promising technology to capture variations of foliage characteristics in forests to support the development of functional linkages between biophysical and ecological studies. (author)

  18. An integrated tool to assess the role of new planting in PM10 capture and the human health benefits: A case study in London

    The role of vegetation in mitigating the effects of PM10 pollution has been highlighted as one potential benefit of urban greenspace. An integrated modelling approach is presented which utilises air dispersion (ADMS-Urban) and particulate interception (UFORE) to predict the PM10 concentrations both before and after greenspace establishment, using a 10 x 10 km area of East London Green Grid (ELGG) as a case study. The corresponding health benefits, in terms of premature mortality and respiratory hospital admissions, as a result of the reduced exposure of the local population are also modelled. PM10 capture from the scenario comprising 75% grassland, 20% sycamore maple (Acer pseudoplatanus L.) and 5% Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) was estimated to be 90.41 t yr-1, equating to 0.009 t ha-1 yr-1 over the whole study area. The human health modelling estimated that 2 deaths and 2 hospital admissions would be averted per year. - A combination of models can be used to estimate particulate matter concentrations before and after greenspace establishment and the resulting benefits to human health.

  19. Tree Species Classification By Multiseasonal High Resolution Satellite Data

    Elatawneh, Alata; Wallner, Adelheid; Straub, Christoph; Schneider, Thomas; Knoke, Thomas

    2013-12-01

    Accurate forest tree species mapping is a fundamental issue for sustainable forest management and planning. Forest tree species mapping with the means of remote sensing data is still a topic to be investigated. The Bavaria state institute of forestry is investigating the potential of using digital aerial images for forest management purposes. However, using aerial images is still cost- and time-consuming, in addition to their acquisition restrictions. The new space-born sensor generations such as, RapidEye, with a very high temporal resolution, offering multiseasonal data have the potential to improve the forest tree species mapping. In this study, we investigated the potential of multiseasonal RapidEye data for mapping tree species in a Mid European forest in Southern Germany. The RapidEye data of level A3 were collected on ten different dates in the years 2009, 2010 and 2011. For data analysis, a model was developed, which combines the Spectral Angle Mapper technique with a 10-fold- cross-validation. The analysis succeeded to differentiate four tree species; Norway spruce (Picea abies L.), Silver Fir (Abies alba Mill.), European beech (Fagus sylvatica) and Maple (Acer pseudoplatanus). The model success was evaluated using digital aerial images acquired in the year 2009 and inventory point records from 2008/09 inventory. Model results of the multiseasonal RapidEye data analysis achieved an overall accuracy of 76%. However, the success of the model was evaluated only for all the identified species and not for the individual.

  20. Proteomic insights into seed germination in response to environmental factors.

    Tan, Longyan; Chen, Sixue; Wang, Tai; Dai, Shaojun

    2013-06-01

    Seed germination is a critical process in the life cycle of higher plants. During germination, the imbibed mature seed is highly sensitive to different environmental factors.However, knowledge about the molecular and physiological mechanisms underlying the environmental effects on germination has been lacking. Recent proteomic work has provided invaluable insight into the molecular processes in germinating seeds of Arabidopsis, rice (Oryza sativa), soybean (Glycine max), barley (Hordeum vulgare), maize (Zeamays), tea (Camellia sinensis), European beech (Fagus sylvatica), and Norway maple (Acer platanoides) under different treatments including metal ions (e.g. copper and cadmium), drought, low temperature, hormones, and chemicals (gibberellic acid, abscisic acid, salicylic acid, and α-amanitin), as well as Fusarium graminearum infection. A total of 561 environmental factor-responsive proteins have been identified with various expression patterns in germinating seeds. The data highlight diverse regulatory and metabolic mechanisms upon seed germination, including induction of environmental factor-responsive signaling pathways, seed storage reserve mobilization and utilization, enhancement of DNA repair and modification, regulation of gene expression and protein synthesis, modulation of cell structure, and cell defense. In this review, we summarize the interesting findings and discuss the relevance and significance for our understanding of environmental regulation of seed germination. PMID:23986916

  1. 西藏植物的新分布属和新分布种

    于顺利; 李晖; 土艳丽

    2008-01-01

    根据西藏高原生物研究所标本馆馆藏标本,发现有西藏新分布属2个,即马甲子属(Paliurus)和菠萝蜜属(Arctocarpus);西藏新分布种23个,即马甲子(Paliurus ramossissimus)、扁担杆(Grewia biloba)、儿茶(Acacia catechu)、华南皂角(Gleditsia fera)、白背桤叶树(Clethra petelotii)、思茅铁线莲(Clematis ranunculoides var.pterantha)、疏果山蚂蝗(Desmodium griffithianum)、滇南山蚂蝗(Desmodium megaphyllum var.megaphyllum)、芹叶铁线莲(Clematis aethusifolia)、棱喙毛茛(Ranunculus trigonus)、中华水龙骨(Polypodiodes chinensis)、贡山猕猴桃(Actinidia pilosula)、长齿木蓝(Indigofera dolichochaeta)、线叶柳(Salix wihelmsiana var.wihelmsiana)、透茎冷水花(Pilea pumila var.pumila)等.发现栽培种及逸生种3个,即棒叶槭Acer negundo)、木槿(Hibiscus syriacus)和欧洲千里光(Senecio vulgaris).

  2. Vegetation survey of Four Mile Creek wetlands. [Savannah River Plant

    Loehle, C.

    1990-11-01

    A survey of forested wetlands along upper Four Mile Creek was conducted. The region from Road 3 to the creek headwaters was sampled to evaluate the composition of woody and herbaceons plant communities. All sites were found to fall into either the Nyssa sylvatica (Black Gum) -- Persea borbonia (Red Bay) or Nyssa sylvatica -- Acer rubrum (Red Maple) types. These community types are generally species-rich and diverse. Previous studies (Greenwood et al., 1990; Mackey, 1988) demonstrated contaminant stress in areas downslope from the F- and H-Area seepage basins. In the present study there were some indications of contaminant stress. In the wetland near H-Area, shrub basal area, ground cover stratum species richness, and diversity were low. In the area surrounding the F-Area tree kill zone, ground cover stratum cover and shrub basal area were low and ground cover stratum species richness was low. The moderately stressed site at F-Area also showed reduced overstory richness and diversity and reduced ground cover stratum richness. These results could, however, be due to the very high basal area of overstory trees in both stressed F-Area sites that would reduce light availability to understory plants. No threatened or endangered plant species were found in the areas sampled. 40 refs., 4 figs., 8 tabs.

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

    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

  4. Conversion trials in mixed coppices of Gargano (Puglia, Italy: first results

    2009-03-01

    Full Text Available Six plots have been drawn in an mixed aged coppice stand, 40 years after last coppicing; they represent a typical expression of Doronico-Carpinetum phytosociological association and they are characteristic of many woods of Gargano’s territory, composed by Quercus cerris L. (turkey oak, Quercus pubescens Willd. (downy oak, Acer opalus Mill. (italian maple, Carpinus betulus L. (european hornbeam, Ostrya carpinifolia Scop. (hop hornbeam. Compared treatments are: natural evolution of the coppice without thinning versus two thinning regimes with different intensity, both aimed to convert the stands into high forests. 1200 and 1600 stems per hectare were released in the conversion plots. Plots, control and treated in 2001, have been measured before and immediately after thinning and remeasured five years later. At the present time, stands are characterized by a basically monolayered structure, in which turkey oak is prevalent in term of basal area. Moreover in thinned areas, losses on the released shoots number are unimportant both in absolute and in percent terms; in control plot, instead, competition by plants of upper storey on the dominated ones means high values of mortality.

  5. Antiangiogenic Activity and Pharmacogenomics of Medicinal Plants from Traditional Korean Medicine

    Ean-Jeong Seo

    2013-01-01

    Full Text Available Aim. In the present study, we investigated the antiangiogenic properties of 59 plants used in traditional Korean medicine. Selected phytochemicals were investigated in more detail for their modes of action. Methods. A modified chicken-chorioallantoic-membrane (CAM assay using quail eggs was applied to test for antiangiogenic effects of plant extracts. A molecular docking in silico approached the binding of plant constituents to the vascular endothelial growth factor receptors 1 and 2 (VEGFR1, VEGFR2. Microarray-based mRNA expression profiling was employed to correlate the 50% inhibition concentrations (IC50 of a panel of 60 NCI cell lines to these phytochemicals. Results. Extracts from Acer mono leaves, Reynoutria sachalniensis fruits, Cinnamomum japonicum stems, Eurya japonica leaves, Adenophora racemosa whole plant, Caryopteris incana leaves-stems, and Schisandra chinensis stems inhibited angiogenesis more than 50% in quail eggs. Selected phytochemicals from Korean plants were analyzed in more detail using microarray-based mRNA expression profiles and molecular docking to VEGFR1 and VEGFR2. These results indicate multifactorial modes of action of these natural products. Conclusion. The antiangiogenic activity of plants used in traditional Korean medicine implicates their possible application for diseases where inhibition of blood vessel formation is desired, for example, cancer, macular degeneration, diabetic retinopathy and others.

  6. Relationships between xylem embolism and eco-physiological indices in eight woody plants in sltu(Ⅱ):The relationship with photosynthetic eco-physiological indices

    AN Feng; CAI Jing; JIANG Zaimin; ZHANG Yuanying; ZHAO Pingjuan; ZHANG Shuoxin

    2007-01-01

    The relationship between xylem embolism and eco-physiology indices (I.e.photosynthetic available radiation,temperature,relative humidity,photosynthetic rate,transpiration rate,stomatal conductance and water use efficiency) in eight tree species was investigated in situ.The species studied,Robinia pseudoacacia L.,Acer truncatum Bge.,Hippophae rhamnoides L.,Ulmus pumila L.,Pinus tabulaeformis Carr., Pinus bungeana Zucc.ex Endl.,Ligustrum lucidum Ait.,and Salix matsudana Koidz.f.pendula Schneid,grow well on the Xilin campus of Northwest A&F University.Results indicated that photosynthetic available radiation,air temperature and relative humidity can affect xylem embolism by daily adjustment of stomatal conductance,transpiration rate and water relations of a tree.Embolism was a common case in the daily growth of the plants,and there was some correlation between xylem embolism and photosynthetic rate,transpiration rate,stornatal conductance,and water use efficiency.Embolism may thus be an adaptive mechanism by some tree species to water stress.

  7. Ecology and Taxonomy of Water Canyon, Canadian County, Oklahoma, Master's Thesis, University of Oklahoma 1961 [Revised 2013

    Constance E. Taylor

    2014-03-01

    Full Text Available Numerous canyons have been cut into the Rush Springs Sandstone of Permian age in West Central Oklahoma and subsequently refilled. Some of these canyons have been partly exposed by erosion of the sediment fill. Fossils collected indicate the canyon fill is sub-Pleistocene to geologically recent. The microclimate of these canyons is more mesic compared to the dryer prairie uplands. Sugar maple (Acer saccharum persists there, far west of its other locations in very eastern Oklahoma. Beginning in 1932 several of these sediment-filled canyons began a process of rapid erosion, exposing the rock walls of the canyons. This study is a comparison of Water Canyon and two of its branches: Water Branch Canyon, a stable canyon wooded with mature vegetation including sugar maple and Activity Branch Canyon, a newly excavated canyon branch that began eroding after excessive rainfall in 1932. This study was completed in 1960. Six transects are used to show the distribution of the 233 plant species found in the Water Canyon complex. Herbaceous species generally were unique to each canyon type.

  8. Floodplain forest loss and changes in forest community composition and structure in the upper Mississippi River: a wildlife habitat at risk

    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.

  9. Harvest-related edge effects on prey availability and foraging of hooded warblers in a bottomland hardwood forest.

    John Kilgo

    2005-04-20

    The effects of harvest-created canopy gaps in bottomland hardwood forests on arthropod abundance and, hence, the foraging ecology of birds are poorly understood. I predicted that arthropod abundance would be high near edges of group-selection harvest gaps and lower in the surrounding forest, and that male Hooded Warblers (Wilsonia citrina) foraging near gaps would find more prey per unit time than those foraging in the surrounding forest. In fact, arthropod abundance was greater >100 m from a gap edge than at 0-30 m or 30-100 m from an edge, due to their abundance on switchcane (Arundinaria gigantea); arthropods did not differ in abundance among distances from gaps on oaks (Quercus spp.) or red maple (Acer rubrum). Similarly, Hooded Warbler foraging attack rates were not higher near gap edges: when foraging for fledglings, attack rate did not differ among distances from gaps, but when foraging for themselves, attack rates actually were lower 0-30 m from gap edges than 30-100 m or >100 m from a gap edge. Foraging attack rate was positively associated with arthropod abundance. Hooded Warblers apparently encountered fewer prey and presumably foraged less efficiently where arthropods were least abundant, i.e., near gaps. That attack rates among birds foraging for fledglings were not affected by distance from gap (and hence arthropod abundance) suggests that prey availability may not be limiting at any location across the forest, despite the depressing effects of gaps on arthropod abundance.

  10. Widespread occurrence of expressed fungal secretory peroxidases in forest soils.

    Kellner, Harald; Luis, Patricia; Pecyna, Marek J; Barbi, Florian; Kapturska, Danuta; Krüger, Dirk; Zak, Donald R; Marmeisse, Roland; Vandenbol, Micheline; Hofrichter, Martin

    2014-01-01

    Fungal secretory peroxidases mediate fundamental ecological functions in the conversion and degradation of plant biomass. Many of these enzymes have strong oxidizing activities towards aromatic compounds and are involved in the degradation of plant cell wall (lignin) and humus. They comprise three major groups: class II peroxidases (including lignin peroxidase, manganese peroxidase, versatile peroxidase and generic peroxidase), dye-decolorizing peroxidases, and heme-thiolate peroxidases (e.g. unspecific/aromatic peroxygenase, chloroperoxidase). Here, we have repeatedly observed a widespread expression of all major peroxidase groups in leaf and needle litter across a range of forest ecosystems (e.g. Fagus, Picea, Acer, Quercus, and Populus spp.), which are widespread in Europe and North America. Manganese peroxidases and unspecific peroxygenases were found expressed in all nine investigated forest sites, and dye-decolorizing peroxidases were observed in five of the nine sites, thereby indicating biological significance of these enzymes for fungal physiology and ecosystem processes. Transcripts of selected secretory peroxidase genes were also analyzed in pure cultures of several litter-decomposing species and other fungi. Using this information, we were able to match, in environmental litter samples, two manganese peroxidase sequences to Mycena galopus and Mycena epipterygia and one unspecific peroxygenase transcript to Mycena galopus, suggesting an important role of this litter- and coarse woody debris-dwelling genus in the disintegration and transformation of litter aromatics and organic matter formation. PMID:24763280

  11. Widespread occurrence of expressed fungal secretory peroxidases in forest soils.

    Harald Kellner

    Full Text Available Fungal secretory peroxidases mediate fundamental ecological functions in the conversion and degradation of plant biomass. Many of these enzymes have strong oxidizing activities towards aromatic compounds and are involved in the degradation of plant cell wall (lignin and humus. They comprise three major groups: class II peroxidases (including lignin peroxidase, manganese peroxidase, versatile peroxidase and generic peroxidase, dye-decolorizing peroxidases, and heme-thiolate peroxidases (e.g. unspecific/aromatic peroxygenase, chloroperoxidase. Here, we have repeatedly observed a widespread expression of all major peroxidase groups in leaf and needle litter across a range of forest ecosystems (e.g. Fagus, Picea, Acer, Quercus, and Populus spp., which are widespread in Europe and North America. Manganese peroxidases and unspecific peroxygenases were found expressed in all nine investigated forest sites, and dye-decolorizing peroxidases were observed in five of the nine sites, thereby indicating biological significance of these enzymes for fungal physiology and ecosystem processes. Transcripts of selected secretory peroxidase genes were also analyzed in pure cultures of several litter-decomposing species and other fungi. Using this information, we were able to match, in environmental litter samples, two manganese peroxidase sequences to Mycena galopus and Mycena epipterygia and one unspecific peroxygenase transcript to Mycena galopus, suggesting an important role of this litter- and coarse woody debris-dwelling genus in the disintegration and transformation of litter aromatics and organic matter formation.

  12. Economics of short-rotation woody crops plantation at Amana, Iowa

    This paper reports on a 21 ha energy plantation of silver maple (Acer saccharinum) established on an old-field bottomland site near Amana, IA. The project started in 1988 and sponsored by the Oak Ridge National Laboratory, (US Dept. of Energy), is a 6 year cooperative effort of the Amana Society, Department of Forestry, ISU, and the Iowa Dept. of Natural Resources. The objective is to accurately estimate biomass yields and costs of growing wood for energy in a short-rotation, close spacing system under operational conditions. Research is being conducted on spacing rotation, fertilization, groundwater quality, and improved seedlings. A detailed cost accounting system was established to accurately record time and cost data by activity. Establishment costs (rent, site preparation, tree planting) and initial (2 year) cultural management costs (herbicide and mowing) total $1,304/ha. Cost proportions for rent, site preparation, and planting are 11%, 18.2%, and 59.4%, respectively. Cultural management costs incurred through 1990 total $148/ha

  13. Silencio en la contratación. Análisis del Código Civil peruano y de la Convención de Viena sobre compraventa interna- cional de mercaderías

    Luis Cárdenas Rodríguez

    2013-03-01

    Full Text Available En este trabajo se enfoca el rol del silencio en la celebración de contratos. Más que un estudio de teoría general, se busca un acer- camiento práctico a la aplicación de la normativa del Derecho peruano y de la Convención de Viena. Para ello se incluyen alusiones a pronunciamientos jurisprudenciales sobre: contratos de seguro, fianza y compraventa internacional. Se brinda especial atención a los casos donde exista un uso para el comercio o una práctica entre las partes de contratación sin respuesta expresa. Asimismo, se explica la importancia de la buena fe en la calificación del silencio circunstanciado, pues en ocasiones se deriva de ella un deber o una carga de hablar en caso de que no se quiera que se dote al silencio de valor positivo conducente a la conclusión del contrato. Finalmente, se resalta el papel de la buena fe y la costumbre en pos de una actitud flexible frente a novedosos supuestos y perma- nentes exigencias que impone la práctica.

  14. Phytopatological monitoring of Inonotus rickii and GPS-GIS applications, Rome, Italy

    Moriondo M

    2008-06-01

    Full Text Available Plant disease management may be improved by collecting, storing, manipulating, analysing and displaying epidemiological information using a Geographic Information System (GIS, a useful tool to evaluate plant disease problems in a spatial context. In this study, GIS analysis was applied along with global positioning systems (GPS to integrate field data-collected with the spatial distribution of the pathogen Inonotus rickii. This pathogen provokes a decay of sapwood/heartwood and cankers, determining a progressive crown dieback and structural weakness of the trees, therefore increasing risk of branch breaks and tree failures. It is widespread in tropical and subtropical countries and it has already been recorded in many areas in Rome on Acer negundo, Albizia julibrissin, Koelreuteria paniculata, Celtis australis and Platanus x acerifolia. A survey was carried out in different boulevards of A. negundo and A. julibrissin with the aim of evaluating disease symptoms such as sparse foliage, dead twigs and branches, wood decay and presence of fungal structures. In this survey, I. rickii was recorded also on Robinia pseudoacacia, which is a new host. The study allowed to obtain thematic maps showing the spatial distribution of all infected trees, as well as the presence of anamorph and/or teleomorph structures of the fungus. Moreover, a map representing the incidence of the pathogen in different boulevards was obtained. The usefulness of GIS analysis in studies aimed to support and refine management strategies for disease control in urban trees is discussed.

  15. Sustained by First Nations: European newcomers' use of Indigenous plant foods in temperate North America

    Nancy J. Turner

    2012-12-01

    Full Text Available Indigenous Peoples of North America have collectively used approximately 1800 different native species of plants, algae, lichens and fungi as food. When European explorers, traders and settlers arrived on the continent, these native foods, often identified and offered by Indigenous hosts, gave them sustenance and in some cases saved them from starvation. Over the years, some of these species – particularly various types of berries, such as blueberries and cranberries (Vaccinium spp., wild raspberries and blackberries (Rubus spp., and wild strawberries (Fragaria spp., and various types of nuts (Corylus spp., Carya spp., Juglans spp., Pinus spp., along with wild-rice (Zizania spp. and maple syrup (from Acer saccharum – became more widely adopted and remain in use to the present day. Some of these and some other species were used in plant breeding programs, as germplasm for hybridization programs, or to strengthen a crop's resistance to disease. At the same time, many nutritious Indigenous foods fell out of use among Indigenous Peoples themselves, and along with their lessened use came a loss of associated knowledge and cultural identity. Today, for a variety of reasons, from improving people's health and regaining their cultural heritage, to enhancing dietary diversity and enjoyment of diverse foods, some of the species that have dwindled in their use have been “rediscovered” by Indigenous and non-Indigenous Peoples, and indications are that their benefits to humanity will continue into the future.

  16. New approach to the reclamation of the old flotation tailings in Bor

    Dožić Stevan

    2010-01-01

    Full Text Available The old flotation tailings of the Bor copper mine have not been reclaimed for several decades, although it is a serious threat to the environment, especially to some parts of the town. To date, there have been no efficacious attempts of solving the problem by indirect rehabilitation, only several cases of direct reclamation. This paper presents some results of the experiment established on a part of the tailings in the vicinity of the town, where various variants of meliorated and sterile substrates were applied in the biological reclamation with several tree and grass species. The analysis shows that, in the rehabilitation of sterile substrate of the copper mine, it is possible to grow several woody species. The best results were achieved by the species that were planted in the fertile soil layer on the sterile copper mine substrate, and on the mixture of soil and waste. Among the woody species, Robinia pseudoaccacia, Fraxinus excelsior and Acer pseudoplatanus showed the best survival percent, growth, and physiological vitality and the poorest were spruce and common oak.

  17. [Spatial heterogeneity of natural regeneration in a spruce-fir mixed broadleaf-conifer forest in Changbai Mountains].

    Li, Yan-Li; Yang, Hua; Kang, Xin-Gang; Wang, Yan; Yue, Gang; Shen, Lin

    2014-02-01

    Based on fieldwork on a plot of 60 m x 60 m in the Changbai Mountain area of Northeast China in August 2012, the spatial distribution pattern and heterogeneity of natural regeneration in the spruce-fir mixed broadleaf-conifer forest were analyzed using semi-variograms, fractal dimensions and Kriging interpolation methods. The results showed that Abies nephrolepis and Acer mono were the most common regeneration species, accounting for 87.4% of the total. The regeneration seedlings and saplings presented an aggregate distribution pattern with the biggest radius of 9.93 m. Distinct spatial autocorrelation existed among regeneration seedlings and saplings, with 88.7% of variation coming from structure factors (biological and ecological properties and environmental heterogeneity) and 11.3% from random factors. The spatial distribution of the regeneration seedlings and saplings presented anisotropy, with the smallest fractal dimension and strongest spatial heterogeneity from north to south, and the highest fractal dimension and weakest spatial heterogeneity from northeast to southwest. The spatial heterogeneity of heights of seedlings and saplings was greater than that of root collar diameters. The distance of spatial autocorrelation for tree root collar diameters was 29.97 m, and that for heights was 31.86 m. Random factors and structure factors were found to contribute equally to the spatial heterogeneity. PMID:24830227

  18. Antioxidant Activities and Phytochemical Study of Leaf Extracts from 18 Indigenous Tree Species in Taiwan

    Shang-Tse Ho

    2012-01-01

    Full Text Available The objective of this study is to assess antioxidant activities of methanolic extracts from the leaves of 18 indigenous tree species in Taiwan. Results revealed that, among 18 species, Acer oliverianum exhibited the best free radical scavenging activities. The IC50 values were 5.8 and 11.8 μg/mL on DPPH radical and superoxide radical scavenging activities, respectively. In addition, A. oliverianum also exhibited the strongest ferrous ion chelating activity. Based on a bioactivity-guided isolation principle, the resulting methanolic crude extracts of A. oliverianum leaves were fractionated to yield soluble fractions of hexane, EtOAc, BuOH, and water. Of these, the EtOAc fraction had the best antioxidant activity. Furthermore, 8 specific phytochemicals were isolated and identified from the EtOAc fraction. Among them, 1,2,3,4,6-O-penta-galloyl-β-D-glucopyranose had the best free radical scavenging activity. These results demonstrate that methanolic extracts and their derived phytochemicals of A. oliverianum leaves have excellent antioxidant activities and thus they have great potential as sources for natural health products.

  19. Antioxidant activities and phytochemical study of leaf extracts from 18 indigenous tree species in taiwan.

    Ho, Shang-Tse; Tung, Yu-Tang; Chen, Yong-Long; Zhao, Ying-Ying; Chung, Min-Jay; Wu, Jyh-Horng

    2012-01-01

    The objective of this study is to assess antioxidant activities of methanolic extracts from the leaves of 18 indigenous tree species in Taiwan. Results revealed that, among 18 species, Acer oliverianum exhibited the best free radical scavenging activities. The IC(50) values were 5.8 and 11.8 μg/mL on DPPH radical and superoxide radical scavenging activities, respectively. In addition, A. oliverianum also exhibited the strongest ferrous ion chelating activity. Based on a bioactivity-guided isolation principle, the resulting methanolic crude extracts of A. oliverianum leaves were fractionated to yield soluble fractions of hexane, EtOAc, BuOH, and water. Of these, the EtOAc fraction had the best antioxidant activity. Furthermore, 8 specific phytochemicals were isolated and identified from the EtOAc fraction. Among them, 1,2,3,4,6-O-penta-galloyl-β-D-glucopyranose had the best free radical scavenging activity. These results demonstrate that methanolic extracts and their derived phytochemicals of A. oliverianum leaves have excellent antioxidant activities and thus they have great potential as sources for natural health products. PMID:22454657

  20. Effect of Chipping and Solarization on Emergence and Boring Activity of a Recently Introduced Ambrosia Beetle (Euwallacea sp., Coleoptera: Curculionidae: Scolytinae) in Southern California.

    Eatough Jones, Michele; Paine, Timothy D

    2015-08-01

    Polyphagous shot hole borer (Euwallacea sp., Coleoptera: Curculionidae: Scolytinae) has recently invaded southern California. The beetle, along with its associated fungi, Fusarium euwallaceae, Graphium sp., and Acremonium sp., causes branch dieback and tree mortality in a large variety of tree species including avocado (Persea americana Mill.) and box elder (Acer negundo L.). With the spread of the beetle through Los Angeles, Orange, and San Diego Counties in California, there is increasing concern that felled trees and pruned branches infested with polyphagous shot hole borer should receive sanitation treatment to reduce the potential spread of the beetle from the movement of untreated wood. We tested two sanitation methods to reduce beetle populations, chipping with a commercial chipper and solarization by covering logs with clear or black plastic in full sun. Both chipping and solarization decreased beetle emergence and boring activity compared to untreated control logs. Chipping was most effective for chip sizes <5 cm. Solarization was most effective using clear polyethylene sheeting during hot summer months, particularly August, when daily maximum temperatures were ≥35°C. Beetles persisted for 2 mo or more when solarization was applied during the spring or fall. PMID:26470327

  1. Biochemical Composition Suggests Different Roles of Leaf Litter and Fine Roots in Soil Carbon Formation

    Xia, M.; Pregitzer, K. S.; Talhelm, A. F.

    2012-12-01

    Plant litter is a major source of soil organic carbon (C). This litter is not homogenous, but instead primarily composed of fine root and leaf litter that adapted to different physiological functions. These unique functions suggest that root and leaf litter likely have different biochemical traits, and thus different decomposition patterns. However, few studies have compared their substrate quality and contributions to soil C. Also, much less attention has been given to fine roots although they can represent a substantial litter production. Here we hypothesize that 1) leaf litter and fine roots have different substrate quality as they are highly different in biochemical composition; 2) the biochemical composition of leaf litter and fine roots responds differently to the simulated nitrogen (N) deposition. To test these hypotheses, we collected leaf litter and fine roots of Acer saccharum (the dominant species in the northern temperate ecosystems we studied) in both ambient and N addition treatment plots at four sites of Michigan N deposition gradient study. We quantified ten biochemical components thought to be important on decomposition. Strikingly, we found a consistently three-fold higher lignin concentration in fine roots than that in leaf litter (Ptannin (CT) concentration in fine roots (13.13±0.51%) was also substantially higher than that in leaf litter (P< 0.01, 4.63±0.42 %). Tissue CT can inhibit litter decay by both precipitating proteins and by having antimicrobial properties. In contrast, fine roots exhibited lower concentrations of non-structural carbohydrates (NSC), soluble phenolics, and holocellulose (hemicelluloses & cellulose) than leaf litter (P< 0.01). These components are considered more easily accessible, and may stimulate the decay of lignin by providing required energy. Therefore, fine roots of Acer saccharum have a relatively recalcitrant nature based on their distinct biochemical composition, suggesting fine roots may be the major driver

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

    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.

  3. 45S rDNA在多种植物中期染色体上的定位%Physical Mapping of 45S rDNA on Metaphase Chromosomes in Several Plant Species

    刘博; 陈成彬; 李秀兰; 陈瑞阳; 宋文芹

    2006-01-01

    应用荧光原位杂交技术首次确定了日本小檗(Berberis thunbergii DC)、车前(Plantago major L.)、野芹菜(Sanicula lamelligera Hance)、荔枝(Litchi chinensis Sonn.)、槭树(Acer buergerianum Miq.)、天目琼花(Viburnum sargentii Koehne.)、丹参(Salvia miltorrhiza Bunge.)、榆树(Ulmus pumila L.)中45S rDNA在中期染色体上的位置.根据rDNA的位点数和位置的变化,分为四种类型:①在日本小檗、车前和野芹菜中,荧光信号正好位于随体染色体的次缢痕或端部;②荔枝和槭树,分别有1对和3对染色体具随体,但荧光原位杂交却检测到3对和5对染色体上具有杂交信号;③天目琼花,具有4对随体染色体,但仅在其中一对随体上显示了杂交信号;④在丹参和榆树中,有的杂交信号位于着丝粒部位或长臂的末端,杂交信号的数目成奇数.黄瓜(Cucumis sativus L.)的染色体45S rDNA信号正好位于6条染色体的着丝粒部位,这与Dal-Hoe和Hoshi等人的结果是一致的.上述结果表明:45S rDNA可以作为染色体的一个识别指标,对识别染色体的个体性具有一定的参考价值.另外还对45S rDNA位点分布的多态性进行了讨论.%The genomic distribution of ribosomal RNA genes has been determined for the first time by fluo rescence in situ hybridization (FISH) in Berberis thunbergii DC. , Plantago major L. , Sanicula lamelligera Hance, Litchi chinensis Sonn. , Acer buergerianum Miq. , Viburnum sargentii Koehne. , Salvia miltiorrhiza Bunge. , and Ulmus pumila L.. These species could be divided into four groups based on the difference on the number and sites of their rDNA loci: the fluorescence signals lay in the secondary constrictions or the terminal regions of SAT-chromosomes in B. thunbergii, P. major, and S. lamelligera; 3 and 5 pairs of signals were de tected in L. chinensis and A. buergerianum, respectively which had 1 and 3 pairs of satellites respectively ; there were 4 pairs of SAT-chromosomes in V

  4. 昆明树木园枯枝落叶层无脊椎动物群落多样性%Diversity of invertebrate community in leaf litters of Kunming Arboretum, Yunnan Province of Southwest China

    王婧; 聂晶; 张立敏; 谢永辉; 李正跃; 张宏瑞

    2012-01-01

    为了解昆明树木园枯枝落叶层无脊椎动物群落结构及特征,于2010年5月-2011年9对昆明树木园中香樟(Cinnamomum camphora)、圆柏(Sabina chinensis)、玉兰(Magnolia denudata)、云南松(Pinus yunnanensis)、红枫(Acer palmatum cv.Atropuceum)共5个树种的枯枝落叶层无脊椎动物进行采样调查.共采获无脊椎动物25237头,隶属于2门5纲18目15科,其中蜱螨目和弹尾目为优势类群;缨翅目、伪蝎目、半翅目和革翅目为常见类群.采用Shannon多样性指数、Pielou均匀度指数和Simpson优势度指数来衡量5个树种的枯枝落叶层无脊椎动物多样性,结果表明:5个树种的枯枝落叶层中无脊椎动物群落物种组成相似,群落中时空异质性较低;5个树种的枯枝落叶层中共采集菌食性蓟马375头,隶属l科、3属、4种,其中,奇管蓟马属(Allothrips)为云南新纪录属,同时也是昆明树木园菌食性蓟马群落中的绝对优势类群.%An investigation was conducted on the invertebrates in leaf litters under five tree spe-cies ( Cinnamomum camphora, Sabina chinensis, Magnolia denudata, Pinus yunnanensis, and Acer palmatum cv. Atropuceum) in Kunming Arboretum from May 2010 to September 2011, aimed to understand the community structure and characteristics of the invertebrate assemblages in the leaf litters of the five tree species. A total of 25237 invertebrate individuals belonging to 15 families of 18 orders in 5 classes under 2 phyla were collected, among which, Acarina and Col-lembola were the dominant groups, while Thysanoptera, Pseudoscorpionidea, Hemiptera, and Dermaptera were the common groups. Shannon diversity index, Pielou evenness index, and Simpson dominance index were used to compare the diversity of the invertebrate assemblages. A similar species composition of the invertebrate assemblages was observed in the leaf litters of the five tree species, and the spatioternporal heterogeneity of the assemblages was small. In the leaf

  5. Hymenoscyphus fraxineus vs. Hymenoscyphus albidus – A comparative light microscopic study on the causal agent of European ash dieback and related foliicolous, stroma-forming species

    Baral, Hans-Otto; Bemmann, Martin

    2014-01-01

    in combination with molecular work. Hy. fraxineus was described from Europe as a cryptic species that differed from Hy. albidus by molecular data alone. However, the Hy. albidus/Hy. fraxineus species complex represents one of many examples within the ascomycetes in which subtle microscopic differences between closely related species, in this case the presence or absence of croziers at the ascus base, are strictly correlated with molecular characteristics. Two species that closely resemble Hy. albidus and Hy. fraxineus form pseudosclerotia in Aesculus leaves and again differ from each other mainly in the ascus base: Hymenoscyphus aesculi on Aesculus hippocastanum from Europe lacks croziers, whereas Hymenoscyphus honshuanus from Japan on Aesculus turbinata possesses croziers. Other taxa treated here include Hymenoscyphus vacini, a European species growing on stromatized net veins of skeletonized leaves of Acer, and Hymenoscyphus torquatus, a Chinese species on unidentified herbaceous stems. An equivalent stroma-forming North American species on leaves of Fraxinus, Rutstroemia longipes (Rutstroemiaceae), is discussed and compared. A key to the Hymenoscyphus species that form a dark stroma on leaves of Acer, Aesculus, Fraxinus, and Picrasma is provided. PMID:25544935

  6. 秋色叶植物叶片着色与酶活性关系的研究%Study on the Relation between Leaf Coloring and Enzymes Activity in Different Fall-leaf Plants

    王彩娟; 蔺银鼎; 王凯; 贾清芳

    2011-01-01

    Three kinds of fall-leaf plant Acer truncatum Bunge,Rhus typhina Linn and Parthenocissus quinquefolia Planch were used as the materials,the changes of anthocyanin content and the activities of SOD,POD,PPO were dynamically investigated at leaf coloring stages,and the relationship between them was also studied.The results showed that: the anthocyanin content of three kinds of fall-leaf plant determined the leaves coloring degree.The anthocyanin content in three fall-leaf plants tended upwards in line with the process of leaves coloring,the synthesis rate of anthocyanin in Rhus typhina and Parthenocissus tricuspidata ascended faster than Acer truncatum Bunge.The SOD activity showed a drop tendency in the process of color transformation,and the SOD activity was strongly negatively relative with anthocyanin content,suggesting that the SOD activity is not conducive to leaves coloring of fall-leaf plant.The POD activity showed an increasing at first,then showed a decreased tendency,and the relativity between the POD activity and anthocyanin content is different among three kinds of fall-leaf plant.The PPO activity rises along with the color changes and is strongly positively relative with anthocyanin content,further illustrating that the PPO activity plays an important role in the process of leaves coloring of fall-leaf plant.%以元宝枫、火炬、爬山虎3种秋色叶植物为试材,研究了秋叶变色时期叶片花青苷的含量与超氧化物歧化酶(SOD)、过氧化物酶(POD)及多酚氧化酶(PPO)活性的动态变化及相关关系。结果表明:3种秋色叶植物花青苷的含量决定叶片的着色程度。3种秋色叶植物花青苷含量随叶片着色呈上升趋势,火炬和爬山虎花青苷的上升速率比元宝枫快。SOD活性随着叶片着色逐渐下降,与花青苷含量呈极显著负相关,说明其在一定程度上不利于秋色叶植物叶片着色。POD活性表现出先升后降的趋势,3种植物中POD活性

  7. Steel desulphurization with synthetic slag

    Heput, T.

    2007-02-01

    Full Text Available Generally speaking, sulphur is considered a harmful element for steel quality, reason why all the technological steps are being taken in order to eliminate it from the metal bath. This paper deals with the influence of the chemical composition, on the slag quantity and of the bath stirring condition upon the desulphurization process in the casting ladle by treatment with synthetic slag. The experiments were made at an open-hearth plant with the steel tapping in two ladles (the desulphurization was made with synthetic slag at one ladle while the other one was considered standard and at the electric steel plant and for the synthetic slag formation a mix was used, made, according to several receipts, of: lime (50-75%, fluorine (0-17%, bauxite (0-32% and aluminous slag (8-22%. The data were processed in the calculation programs EXCEL and MATLAB, which resulted in a series of correlations between the desulphurization degree and the chemical composition of the slag, respectively the slag quantity both for the charges bubbled with Argon and the unbubbled ones.

    En general, el azufre es considerado un elemento nocivo para la calidad del acero y, por eso, en la práctica, se toman todas las medidas de orden tecnológico para su eliminación del baño metálico. En este trabajo se analiza la influencia de la composición química, de la cantidad de escoria y del estado de agitación del baño sobre el proceso de desulfuración en la cuchara para fundir por tratamiento con escoria sintética. Los experimentos se han realizado en una acería evacuando el acero en dos ollas (en una cuchara se efectuó la desulfuración con escoria sintética y a la otra se consideró como patrón y en un acería eléctrica y para la formación de la escoria sintética se utilizó una mezcla producida según muchas recetas, formada por: cal (50-75%, fluorina (0-17%, bauxita (0-32% y escoria aluminosa (8-22%. Los datos han sido procesados en los programas de c

  8. 四个彩叶树种挥发性有机化合物成分分析%Volatile Organic Compounds from Four Color-leaf Tree Species

    王金凤; 陈卓梅; 韩素芳; 林飞凡

    2015-01-01

    选取枫香(Liquidambar formosana)、榉树(Zelkova serrata)、三角槭(Acer buergerianum)、银杏(Ginkgo biloba)4个园林绿化中常用的彩色乔木树种,采用动态顶空采集法和TDS-GC-MS联用技术,对其挥发性有机物(VOCs)成分进行分析,结果表明:从4种彩色乔木树种中共鉴定出76种VOCs,萜类化合物是4个彩色乔木树种挥发性有机化合物的主要成分,其中,从银杏中共检测到61种VOCs,含萜类13种,相对含量为26.31%,萜类化合物主要是长叶烯(8.26%)和长叶松萜烯(7.79%);从枫香中共检测出31种VOCs,有萜类13种(57.46%),萜类物质主要是长叶烯(35.97%)、长叶环烯(5.15%)、长叶蒎烯(3.15%)、雪松烯(2.81%);从榉树中共检测出29种VOCs中,含有萜类12种(60.03%),萜类化合物主要是长叶烯(36.85%)、长叶环烯(4.52%)、雪松烯(3.37%)、长叶蒎烯(2.96%)、石竹烯(2.73%);从三角槭中共检测出23种 VOCs 中,含有萜类11种(72.67%),萜类化合物主要是长叶烯(47%)、α-蒎烯(7.13%)、长叶环烯(5.23%)、雪松烯(2.6%)。%Four color-leaf tree species likeLiquidambar formosana,Zelkova serrate,Acer buergerianum andGinkgo biloba were selected for collecting volatile organic compounds (VOCs) by dynamic headspace air-circulation method. The collected VOCs were identified by the thermal desorption system gas chromatography/mass spectrum (TDS-GC/MS). The result showed that there were 76 types of VOCs from testes tree species, among them, terpenes occupied the major part. 61 types of VOCs were identified fromG. biloba, including 13 terpenes (about 26.31%), mainly longifolene (8.26%) and longifolene-(V4) (7.79%). 31 types of VOCs were identified fromL. formosana, including 13 terpenes,(57.46%), mainly longifolene (35.97%), longicyclene (5.15%), longipinene (3.15%) and cedrene (2.81%). 29 types of VOCs were identified

  9. Quantifying flooding regime in floodplain forests to guide river restoration

    Christian O. Marks

    2014-09-01

    Full Text Available Abstract Determining the flooding regime needed to support distinctive floodplain forests is essential for effective river conservation under the ubiquitous human alteration of river flows characteristic of the Anthropocene Era. At over 100 sites throughout the Connecticut River basin, the largest river system in New England, we characterized species composition, valley and channel morphology, and hydrologic regime to define conditions promoting distinct floodplain forest assemblages. Species assemblages were dominated by floodplain-associated trees on surfaces experiencing flood durations between 4.5 and 91 days/year, which were generally well below the stage of the two-year recurrence interval flood, a widely-used benchmark for floodplain restoration. These tree species rarely occurred on surfaces that flooded less than 1 day/year. By contrast abundance of most woody invasive species decreased with flooding. Such flood-prone surfaces were jointly determined by characteristics of the hydrograph (high discharges of long duration and topography (low gradient and reduced valley constraint, resulting in increased availability of floodplain habitat with increasing watershed area and/or decreasing stream gradient. Downstream mainstem reaches provided the most floodplain habitat, largely associated with low-energy features such as back swamps and point bars, and were dominated by silver maple (Acer saccharinum. However, we were able to identify a number of suitable sites in the upper part of the basin and in large tributaries, often associated with in-channel islands and bars and frequently dominated by sycamore (Platanus occidentalis and flood disturbance-dependent species. Our results imply that restoring flows by modifying dam operations to benefit floodplain forests on existing surfaces need not conflict with flood protection in some regional settings. These results underscore the need to understand how flow, geomorphology, and species traits

  10. Litter decomposition over broad spatial and long time scales investigated by advanced solid-state NMR: insight into effects of climate, litter quality, and time

    Mao, J.; Chen, N.; Harmon, M. E.; Li, Y.; Cao, X.; Chappell, M.

    2012-12-01

    Advanced 13C solid-state NMR techniques were employed to study the chemical structural changes of litter decomposition across broad spatial and long time scales. The fresh and decomposed litter samples of four species (Acer saccharum (ACSA), Drypetes glauca (DRGL), Pinus resinosa (PIRE), and Thuja plicata (THPL)) incubated for up to 10 years at four sites under different climatic conditions (from Arctic to tropical forest) were examined. Decomposition generally led to an enrichment of cutin and surface wax materials, and a depletion of carbohydrates causing overall composition to become more similar compared with original litters. However, the changes of main constituents in the four litters were inconsistent with the four litters following different pathways of decomposition at the same site. As decomposition proceeded, waxy materials decreased at the early stage and then gradually increased in PIRE; DRGL showed a significant depletion of lignin and tannin while the changes of lignin and tannin were relative small and inconsistent for ACSA and THPL. In addition, the NCH groups, which could be associated with either fungal cell wall chitin or bacterial wall petidoglycan, were enriched in all litters except THPL. Contrary to the classic lignin-enrichment hypothesis, DRGL with low-quality C substrate had the highest degree of composition changes. Furthermore, some samples had more "advanced" compositional changes in the intermediate stage of decomposition than in the highly-decomposed stage. This pattern might be attributed to the formation of new cross-linking structures, that rendered substrates more complex and difficult for enzymes to attack. Finally, litter quality overrode climate and time factors as a control of long-term changes of chemical composition.

  11. Living part on soil bioengineering structures in Appennino Tosco-emiliano

    Guastini, Enrico; Preti, Federico; Dani, Andrea

    2014-05-01

    From analisys headed up in soil bioengineered areas in different parts of Tuscany, the suitest root systems in slope stabilization turn out to be those spreading from seed-born plants, while adventitious roots from cuttings are often absent in the part more distant from the neck, and in some cases are insufficient to grant life support just in case of minor stress conditions. Genus Alnus shows it's adaptation capability to restore initial restoration steps and to create renovation prerequisites for other species through ammending litter production and symbiosis for nitrogen fixation with Frankia genus bacteria; other similar symbiosis (with Rhizobium and fungi) are carried out by Robinia pseudacacia. Soil fecundity increase is confirmed by the following entrance of more demanding species, as Ostrya carpinifolia and Acer pseudoplatanus at the tree level, Urtica dioica and Rubus Ulmifolius (nitrophilouses) at grass level. In the project phase it ought to imagine a well-structured implant, including rooted plants, cuttings and posibly a seed mix of colonising species aiming to form a germplasm on the structure itself in order to sprout whenever the local conditions allow it. Verifying that many after developed species came from ornithocore dissemination (Ficus carica, Pinus spp., Rosa canina, Sambucus nigra), lead to toughts about bedding out bird-attracting species on structures in order to realise a faster (and maybe more complex) succession development. This higher velocity could grant in a shorter period the production of a root mass spread in a more disomogeneous and complex pattern than that deriving from cuttings disposed in the traditional way; such a variability could allow a better interaction with other biological factors in the soil (bacteria, fungi, nematodes, ...) that are important for the plant nutrient cicle (Ohsowski et al., 2012) and then the constituion of an articulate, long-term system.

  12. Photosynthetic responses of forest understory tree species to long-term exposure to elevated carbon dioxide concentration at the Duke Forest FACE experiment

    Tree species growing within the forest understory contribute to the overall carbon balance of forest ecosystems in addition to representing many of the species that occur in the overstory of mature ecosystems. This article described a 7 year study investigating the responses of forest understory tree species to increasing concentrations of atmospheric carbon dioxide (CO2). The study examined the photosynthetic responses of Acer rubrum L., Carya glabra Mill., Cercis Canadensis L., and Liquidambar styraciflua L. during their seventh year of exposure to elevated CO2 at the Duke Forest Free Air Carbon Enrichment (FACE) experiment to determine whether photosynthetic down-regulation had occurred, as well as to determine whether the enhancement of photosynthesis observed during the first year of exposure to elevated CO2 was sustained. The study was conducted to test a previous hypothesis that significant photosynthetic down-regulation would be observed after 7 years of exposure to elevated CO2. Photosynthetic CO2 response and light response curves were measured, as well as chlorophyll fluorescence, chlorophyll concentration and foliar nitrogen (N). Results showed that exposure to elevated CO2 increased photosynthesis in all species measured after 7 years of treatment. The greatest photosynthetic increase was observed near saturating irradiances. In all species, elevated CO2 increased electron transport efficiency but did not significantly alter carboxylation efficiency. Quantum yield as estimated by light curves, chlorophyll concentration, and foliar N concentrations was unaffected by elevated CO2. It was concluded that there was scant evidence of progressive N limitation of leaf-level processes in the understory species after 7 years of exposure to elevated CO2 in the experiment. 42 refs., 2 tabs., 4 figs

  13. 八达岭林场水源涵养林多样性特征分析%Analysis on the Water Conservation Forest Diversity of Badaling Forest Farm

    张林玉; 梁晶

    2014-01-01

    对八达岭林场16种林分类型水源涵养林物种丰富度、多样性、均匀度等多样性特征指标进行了研究。结果表明:在西沟油松林、杂木林和黑桦林中多样性指数变化表现为灌木>草本>乔木,在其他群落类型中多样性指数与丰富度指数一致;多样性指数在刺槐残次林、侧柏黄栌混交林、油松林、元宝枫林和华山松林中表现为草本层>灌木层>乔木层,华北落叶松林群落内部各层次物种多样性指数为灌木层>草本层>乔木层。%We studied the diversity index of species richness,diversity and uniformity of 16 types of water conservation forests in Badaling forest farm.Results showed that the diversity index change in Xigou pine forest and shaw and black birch forest is in the form of shrub>herb>tree,in other communities it is same with the richness index;in secondary forest of Platycladus orientalis,Robinia pseudoacacia Cotinus coggy-gria mixed forest,pine forest,Acer truncatum and Huashan pine forest,the diversity index is in the order of herb layer>shrub layer>tree layer,the species diversity among all levels of larch forest community is shrub layer>herb layer>tree layer.

  14. Chronic nitrogen deposition alters tree allometric relationships: implications for biomass production and carbon storage.

    Ibáñez, Inés; Zak, Donald R; Burton, Andrew J; Pregitzer, Kurt S

    2016-04-01

    As increasing levels of nitrogen (N) deposition impact many terrestrial ecosystems, understanding the potential effects of higher N availability is critical for forecasting tree carbon allocation patterns and thus future forest productivity. Most regional estimates of forest biomass apply allometric equations, with parameters estimated from a limited number of studies, to forest inventory data (i.e., tree diameter). However most of these allometric equations cannot account for potential effects of increased N availability on biomass allocation patterns. Using 18 yr of tree diameter, height, and mortality data collected for a dominant tree species (Acer saccharum) in an atmospheric N deposition experiment, we evaluated how greater N availability affects allometric relationships in this species. After taking into account site and individual variability, our results reveal significant differences in allometric parameters between ambient and experimental N deposition treatments. Large trees under experimental N deposition reached greater heights at a given diameter; moreover, their estimated maximum height (mean ± standard deviation: 33.7 ± 0.38 m) was significantly higher than that estimated under the ambient condition (31.3 ± 0.31 m). Within small tree sizes (5-10 cm diameter) there was greater mortality under experimental N deposition, whereas the relative growth rates of small trees were greater under experimental N deposition. Calculations of stemwood biomass using our parameter estimates for the diameter-height relationship indicated the potential for significant biases in these estimates (~2.5%), with under predictions of stemwood biomass averaging 4 Mg/ha lower if ambient parameters were to be used to estimate stem biomass of trees in the experimental N deposition treatment. As atmospheric N deposition continues to increase into the future, ignoring changes in tree allometry will contribute to the uncertainty associated with aboveground carbon storage

  15. Characterization of Transpiration in a Deciduous Forest of the US Midwest

    Dragoni, D.; Caylor, K. K.; Schmid, H.

    2006-12-01

    The exchange of water between atmosphere and biosphere is an important determinant of climate and the productivity of vegetation, as transpiration involves substantial amounts of energy. Knowing how transpiration changes over seasonal and diurnal cycles can help increase the understanding of how a forest reacts to changes in the biosphere and atmosphere on both short and long time scales. A study was conducted to characterize the daily and seasonal variation of transpiration in sugar maple (Acer Saccharum) at the Morgan-Monroe State Forest (MMSF) AmeriFlux site in Indiana (USA), were this species represent more than 25% of the forest basal area. Transpiration was estimated by up-scaling single point measurements of sap flow density obtained using the heat-pulse technique. To characterize the variability of sap flow density in the deep sapwood of sugar maples, 3 to 4 radial profiles were obtained for each sampled tree at different positions around the trunk. Different approaches were then tested to scale up to whole tree sap flow. Seventeen trees of different diameter were sampled by three roving sap flow systems, taking measurements from each tree for 5-7 contiguous days. Because of the small scale but complex topography in the area and the relatively shallow soil, particular attention was given to the effect of spatial and temporal variability of soil moisture content on transpiration; for this reason, sampled trees were selected along a topographic gradient and soil water content was measured in the proximity of each tree. Meteorological measurements taken at the nearby MMSF AmeriFlux tower were used to explain transpiration variability in terms of vapor pressure deficit, and solar radiation, while eddy- covariance measurements of latent heat flux were related to the up-scaled transpiration of sugar maples in the study area.

  16. Technetium-99 cycling in maple trees: Characterization of changes in chemical form

    Prior field studies near an old radioactive waste disposal site at Oak Ridge, TN, indicated that following root uptake, metabolism by deciduous trees rendered 99Tc less biogeochemically mobile than expected, based on chemistry of the pertechnetate (TcO-4) anion. Subsequently, the form of technetium (Tc) in maple tree (Acer sp.) sap, leaves, wood and forest leaf litter was characterized using one or more of the following methods: dialysis, physical fractionation, chemical extraction, gel permeation chromatography, enzymatic extraction, or thin layer chromatography (TLC) on silica gel. Chromatography (Sephadex G-25) of TcO-4 incubated in vitro with tree sap showed it to behave similar to TcO-4 anion. When labeled wood and leaf tissues were processed using a tissue homogenizer, 15% and 40%, respectively, of the Tc was solubilized into phosphate buffer. Most (65% to 80%) of the solubilized Tc passing a 0.45-micron filter also passed through an ultrafiltration membrane with a nominal molecular weight cutoff of 10,000 atomic mass units (amu). A majority (72% to 80%) of the Tc in wood could be chemically removed by successive extractions with ethanol, water and weak mineral acid. These same extractants removed only 23% to 31% of the Tc from maple leaves or forest floor leaf litter. Most of the Tc in leaves and leaf litter was removed only by strongly alkaline reagents typically used to release structural polysaccharides (hemicelluloses) from plant tissues. Chromatography (Sephadex G-25) of the ethanol-water extract from wood and the alkaline extract from leaves demonstrated that Tc in these extracts was not principally TcO-4 but was complexed with molecules greater than 1000 amu. Incubations of leaf and wood homogenates with protease approximately doubled the amount of Tc released from contaminated tissues

  17. Air quality in the mountain climate-balneological resort Kislovodsk

    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.

  18. 湘西洛塔禁伐恢复林木本植物群落特征研究%STUDIES ON THE RESTORATION TREE SPECIES COMMUNITY CHARACTERISTICS OF LUOTA REGION IN WESTERN HUNAN PROVINCE

    郭敏; 薛跃规; 朱远锋; 李兆林

    2001-01-01

    This paper studies the restoration community for 20a of Luotaregion in western Hunan province.The results are shown as follows:the ap pearance of this community is characterized by the middle and low phaneropytes s uch as Acer davidii,Dendrobenthamia capitata,et al.The shrub layer occupies the important position in the structure of the community.There are 96 kinds of t rees,shrubs and vine species in this community.It shows that the community diversity is hig her than that of restoring for 40a.The structure of the community is not steadil y developing toward the climax state.%对湘西洛塔喀斯特地貌植物群落20年恢复林进行样方调查,结果表明:该植物群落的外貌由青榨槭、四照花、枫香、杜英、楠木等中小高位芽植物决定,其结构主要以灌木层为主,整个群落正处于一个向顶极状态发展的阶段.调查的数据还表明,在50 m×4 m样地内有木本植物96种,比自然恢复40年的阿堀村风水林物种多样性高.个体高度与径级结构以灌木层和幼苗占绝对数量,说明该群落的物种丰富,其木本植物的配置还未达到稳定状态,正向着顶极状态发展.

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

    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. Substrate influences ecophysiological performance of tree seedlings.

    Pröll, Gisela; Hietz, Peter; Delaney, Christina M; Katzensteiner, Klaus

    2016-01-01

    Unfavourable soil conditions frequently limit tree regeneration in mountain forests on calcareous bedrock. Rocky, shallow organic soils on dolomite pose a particular problem for tree regeneration due to commonly restricted water and nutrient supplies. Moreover, an often dense layer of understorey vegetation competes for the limited resources available. Hence, an array of interacting factors impairs tree seedlings' performance on dolomite, but there is little information on the ecophysiological mechanisms. We studied the effects of substrate, competing vegetation and foliar nutrient concentrations on the photosynthetic rate (A), stomatal conductance (gs) and leaf water potentials (ψ) of sycamore (Acer pseudoplatanus L.), beech (Fagus sylvatica L.), spruce [Picea abies (L.) Karst.] and larch (Larix decidua Mill.) under controlled (well-watered/drought-stressed) conditions and under prevailing field conditions. While A and gs of well-watered spruce in the pot experiment were reduced by the mineral substrate, the organic dolomite substrate with dense competing vegetation reduced gs and ψ of sycamore, spruce and larch under drought-stressed conditions in the field. For sycamore and spruce, A and gs were strongly correlated with foliar nitrogen (N) and potassium (K) concentrations in the pot experiment. In contrast, soil water primarily affected beech and larch. Finally, dense competing vegetation negatively affected A and gs of spruce and A of larch on dolomite. Our results highlight the critical role of N, K and water availability for tree seedlings in shallow soils on calcareous bedrock. On these sites, natural tree regeneration is at particular risk from episodic drought, a likely consequence of climate change. PMID:26446268

  1. Particulate organic matter quality influences nitrate retention and denitrification in stream sediments: evidence from a carbon burial experiment

    Stelzer, Robert S.; Scott, J. Thad; Bartsch, Lynn; Parr, Thomas B.

    2014-01-01

    Organic carbon supply is linked to nitrogen transformation in ecosystems. However, the role of organic carbon quality in nitrogen processing is not as well understood. We determined how the quality of particulate organic carbon (POC) influenced nitrogen transformation in stream sediments by burying identical quantities of varying quality POC (northern red oak (Quercus rubra) leaves, red maple (Acer rubrum) leaves, red maple wood) in stream mesocosms and measuring the effects on nitrogen retention and denitrification compared to a control of combusted sand. We also determined how POC quality affected the quantity and quality of dissolved organic carbon (DOC) and dissolved oxygen concentration in groundwater. Nitrate and total dissolved nitrogen (TDN) retention were assessed by comparing solute concentrations and fluxes along groundwater flow paths in the mesocosms. Denitrification was measured by in situ changes in N2 concentrations (using MIMS) and by acetylene block incubations. POC quality was measured by C:N and lignin:N ratios and DOC quality was assessed by fluorescence excitation emission matrix spectroscopy. POC quality had strong effects on nitrogen processing. Leaf treatments had much higher nitrate retention, TDN retention and denitrification rates than the wood and control treatments and red maple leaf burial resulted in higher nitrate and TDN retention rates than burial of red oak leaves. Leaf, but not wood, burial drove pore water to severe hypoxia and leaf treatments had higher DOC production and different DOC chemical composition than the wood and control treatments. We think that POC quality affected nitrogen processing in the sediments by influencing the quantity and quality of DOC and redox conditions. Our results suggest that the type of organic carbon inputs can affect the rates of nitrogen transformation in stream ecosystems.

  2. Investigation of pulsatile flowfield in healthy thoracic aorta models.

    Wen, Chih-Yung; Yang, An-Shik; Tseng, Li-Yu; Chai, Jyh-Wen

    2010-02-01

    Cardiovascular disease is the primary cause of morbidity and mortality in the western world. Complex hemodynamics plays a critical role in the development of aortic dissection and atherosclerosis, as well as many other diseases. Since fundamental fluid mechanics are important for the understanding of the blood flow in the cardiovascular circulatory system of the human body aspects, a joint experimental and numerical study was conducted in this study to determine the distributions of wall shear stress and pressure and oscillatory WSS index, and to examine their correlation with the aortic disorders, especially dissection. Experimentally, the Phase-Contrast Magnetic Resonance Imaging (PC-MRI) method was used to acquire the true geometry of a normal human thoracic aorta, which was readily converted into a transparent thoracic aorta model by the rapid prototyping (RP) technique. The thoracic aorta model was then used in the in vitro experiments and computations. Simulations were performed using the computational fluid dynamic (CFD) code ACE+((R)) to determine flow characteristics of the three-dimensional, pulsatile, incompressible, and Newtonian fluid in the thoracic aorta model. The unsteady boundary conditions at the inlet and the outlet of the aortic flow were specified from the measured flowrate and pressure results during in vitro experiments. For the code validation, the predicted axial velocity reasonably agrees with the PC-MRI experimental data in the oblique sagittal plane of the thoracic aorta model. The thorough analyses of the thoracic aorta flow, WSSs, WSS index (OSI), and wall pressures are presented. The predicted locations of the maxima of WSS and the wall pressure can be then correlated with that of the thoracic aorta dissection, and thereby may lead to a useful biological significance. The numerical results also suggest that the effects of low WSS and high OSI tend to cause wall thickening occurred along the inferior wall of the aortic arch and the

  3. BIFoR FACE: A ten-year Free-Air Carbon Dioxide Enrichment (FACE) Experiment in Old Growth Deciduous English Woodland

    Thomas, R. M.; MacKenzie, A. R.; Ellsworth, D.; Hemming, D.; Crous, K.; Pope, F.; Blaen, P.; Poynter, A.; Hamilton, L.; Blenkhorn, D.; Jarvis-Rouse, F.

    2015-12-01

    The Birmingham Institute of Forest research (BIFoR) will perform fundamental physical, biological, ecological, social and cultural research of direct relevance to forested landscapes worldwide. A core platform for BIFoR to study the ten-year response of a mature temperate deciduous forest ecosystem to against a large step-change in atmospheric [CO2] is the BIFoR Free-Air Carbon Dioxide Enrichment (FACE) experiment. BIFoR FACE is being established in Mill Haft, a mature (~150 year-old) oak (Quercus robur) and hazel (Corylus avellana) coppice-with-standards woodland in central England. The facility will enable elevated CO2 (eCO2) treatments to be introduced in 30 m diameter rings (3 treatment and 6 control plots), commencing in spring 2016. Under eCO2 conditions primary research questions will investigate carbon uptake and storage, corresponding nutrient limitations, and biodiversity and ecosystem responses. As well as describing the facility and experimental design, we present baseline data collected throughout 2015, prior to fumigation. These data include: biophysical tree properties; atmospheric CO2/H2O fluxes; airborne and ground laser scatterometry; leaf area index; geophysical survey data; phenology camera derivatives; soil and water chemical and physical properties; and invertebrate surveys. Data from an intensive campaign conducted during august 2015 are also shown, including in- and above- canopy characterisation of biogenic VOCs using a Proton Transfer Reaction Mass Spectrometer, aerosol loading including bioaerosols, and enhanced atmospheric chemistry. Further campaign results are presented from leaf level photosynthetic carbon-dioxide response curve (A/Ci) performed at different canopy heights on oak trees, and on the dominant understory species - hazel and sycamore (Acer pseudoplatinus) across the site. BIFoR FACE is an exciting new international facility for forest science - ideas for collaborations are encouraged. Please see http

  4. Miocene fossil plants from Bukpyeong Formation of Bukpyeong Basin in Donghae City, Gangwon-do Province, Korea and their palaeoenvironmental implications

    Jeong, Eun Kyoung; Kim, Hyun Joo; Uemura, Kazuhiko; Kim, Kyungsik

    2016-04-01

    The Tertiary sedimentary basins are distributed along the eastern coast of Korean Peninsula. The northernmost Bukpyeong Basin is located in Donghae City, Gangwon-do Province, Korea. The Bukpyeong Basin consists of Bukpyeong Formation and Dogyeongri Conglomerate in ascending order. The geologic age of Bukpyeong Formation has been suggested as from Early Miocene to Pliocene, In particular, Lee & Jacobs (2010) suggested the age of the Bukpyeong Formation as late Early Miocene to early Middle Miocene based on the fossils of rodent teeth. Sedimentary environment has been thought as mainly fresh water lake and/or swamp partly influenced by marine water. Lately, new outcrops of Bukpyeong Formation were exposed during the road construction and abundant fossil plants were yielded from the newly exposed outcrops. As a result of palaeobotanical studies 47 genera of 23 families have been found. This fossil plant assemblage is composed of gymnosperms and dicotyledons. Gymnosperms were Pinaceae (e.g., Pinus, Tsuga), Sciadopityaceae (e.g., Sciadopitys) and Cupressaceae with well-preserved Metasequoia cones. Dicotyledons were deciduous trees such as Betulaceae (e.g., Alnus, Carpinus) and Sapindaceae (e.g., Acer, Aesculus, Sapindus), and evergreen trees such as evergreen Fagaceae (e.g., Castanopsis, Cyclobalanopsis, Pasania) and Lauraceae (e.g., Cinnamomum, Machilus). In addition, fresh water plants such as Hemitrapa (Lytraceae) and Ceratophyllum (Ceratophyllaceae) were also found. The fossil plant assemblage of the Bukpyeong Formation supported the freshwater environment implied by previous studies. It can be suggested that the palaeoflora of Bukpyeong Formation was oak-laurel forest with broad-leaved evergreen and deciduous trees accompanying commonly by conifers of Pinaceae and Cupressaceae under warm-temperate climate.

  5. Leaf area and foliar biomass relationships in northern hardwood forests located along an 800 km acid deposition gradient

    The canopies of northern hardwood forests dominated by sugar maple (Acer saccharum Marsh.) were examined at five locations spanning 800 km along an acid deposition and climatic gradient in the Great Lakes region. Leaf area index (LAI) calculated from litterfall ranged from 6.0 to 8.0 in 1988, from 4.9 to 7.9 in 1989, and from 5.3 to 7.8 in 1990. The data suggest that maximum LAI for the sites is between 7 and 8. Insect defoliation and the allocation of assimilates to reproductive parts in large seed years reduced LAI by up to 34%. Allometric equations for leaf area and foliar biomass were not significantly different among sites. They predicted higher LAI values than were estimated from litterfall and could not account for the influences of defoliation and seed production. Canopy transmittance was a viable alternative for estimating LAI. Extinction coefficients (K) of 0.49 to 0.65 were appropriate for solar elevations of 63 degree to 41 degree. Patterns of specific leaf area (SLA) were similar for the sites. Average sugar maple SLA increased from 147 cm2g-1 in the upper 5 m of the canopy to 389 cm2g-1 in the seeding layer. Litterfall SLA averaged 196 cm2g-1 for all species and 192 cm2g-1 for sugar maple. Similarity among the sites in allometric relationships, maximum LAI, canopy transmittance, and patterns of SLA suggests these characteristics were controlled primarily by the similar nutrient and moisture availability at the sites. A general increasing trend in litter production along the gradient could not be attributed to N deposition or length of growing season due to year to year variability resulting from insect defoliation and seed production

  6. Calibrating abundance indices with population size estimators of red back salamanders (Plethodon cinereus in a New England forest

    Ahmed A. Siddig

    2015-05-01

    Full Text Available Herpetologists and conservation biologists frequently use convenient and cost-effective, but less accurate, abundance indices (e.g., number of individuals collected under artificial cover boards or during natural objects surveys in lieu of more accurate, but costly and destructive, population size estimators to detect and monitor size, state, and trends of amphibian populations. Although there are advantages and disadvantages to each approach, reliable use of abundance indices requires that they be calibrated with accurate population estimators. Such calibrations, however, are rare. The red back salamander, Plethodon cinereus, is an ecologically useful indicator species of forest dynamics, and accurate calibration of indices of salamander abundance could increase the reliability of abundance indices used in monitoring programs. We calibrated abundance indices derived from surveys of P. cinereus under artificial cover boards or natural objects with a more accurate estimator of their population size in a New England forest. Average densities/m2 and capture probabilities of P. cinereus under natural objects or cover boards in independent, replicate sites at the Harvard Forest (Petersham, Massachusetts, USA were similar in stands dominated by Tsuga canadensis (eastern hemlock and deciduous hardwood species (predominantly Quercus rubra [red oak] and Acer rubrum [red maple]. The abundance index based on salamanders surveyed under natural objects was significantly associated with density estimates of P. cinereus derived from depletion (removal surveys, but underestimated true density by 50%. In contrast, the abundance index based on cover-board surveys overestimated true density by a factor of 8 and the association between the cover-board index and the density estimates was not statistically significant. We conclude that when calibrated and used appropriately, some abundance indices may provide cost-effective and reliable measures of P. cinereus

  7. Aboveground Net Primary Productivity in a Riparian Wetland Following Restoration of Hydrology

    Melissa Koontz

    2016-02-01

    Full Text Available This research presents the initial results of the effects of hydrological restoration on forested wetlands in the Mississippi alluvial plain near Memphis, Tennessee. Measurements were carried out in a secondary channel, the Loosahatchie Chute, in which rock dikes were constructed in the 1960s to keep most flow in the main navigation channel. In 2008–2009, the dikes were notched to allow more flow into the secondary channel. Study sites were established based on relative distance downstream of the notched dikes. Additionally, a reference site was established north of the Loosahatchie Chute where the dikes remained unnotched. We compared various components of vegetation composition and productivity at sites in the riparian wetlands for two years. Salix nigra had the highest Importance Value at every site. Species with minor Importance Values were Celtis laevigata, Acer rubrum, and Plantanus occidentalis. Productivity increased more following the introduction of river water in affected sites compared to the reference. Aboveground net primary productivity was highest at the reference site (2926 ± 458.1 g·m−2·year−1, the intact site; however, there were greater increase at the sites in the Loosahatchie Chute, where measurements ranged from 1197.7 ± 160.0 g m−2·year−1·to 2874.2 ± 794.0 g·m−2·year−1. The site furthest from the notching was the most affected. Pulsed inputs into these wetlands may enhance forested wetland productivity. Continued monitoring will quantify impacts of restored channel hydrology along the Mississippi River.

  8. Investigation of free amino acid, total phenolics, antioxidant activity and purine alkaloids to assess the health properties of non-Camellia tea

    Wu Bi

    2016-03-01

    Full Text Available To find novel functional beverages from folk teas, 33 species of frequently used non-Camellia tea (plants other than Camellia were collected and compared with Camellia tea (green tea, pu-erh tea and black tea for the first time. Data are reported here on the quantities of 20 free amino acids (FAAs and three purine alkaloids (measured by UHPLC, total polyphenols (measured by Folin-Ciocalteu assay, and antioxidant activity (DPPH. The total amounts of FAAs in non-Camellia tea (0.62–18.99 mg/g are generally less than that of Camellia tea (16.55–24.99 mg/g. However, for certain FAAs, the quantities were much higher in some non-Camellia teas, such as γ-aminobutyric acid in teas from Ampelopsis grossedentata, Isodon serra and Hibiscus sabdariffa. Interestingly, theanine was detected in tea from Potentilla fruticosa (1.16±0.81 mg/g. Furthermore, the content of polyphenols in teas from A. grossedentata, Acer tataricum subsp. ginnala are significantly higher than those from Camellia tea; teas from I. serra, Pistacia chinensis and A. tataricum subsp. ginnala have remarkable antioxidant activities similar to the activities from green tea (44.23 μg/mL. Purine alkaloids (caffeine, theobromine and theophylline were not detected in non-Camellia teas. The investigation suggest some non-Camellia teas may be great functional natural products with potential for prevention of chronic diseases and aging, by providing with abundant polyphenols, antioxidants and specific FAAs.

  9. 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

    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.

  10. Toward an improved model of maple sap exudation: the location and role of osmotic barriers in sugar maple, butternut and white birch.

    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

  11. Transport, compartmentation, and metabolism of homoserine in higher plant cells. Carbon-13- and phosphorus-31-nuclear magnetic resonance studies

    The transport, compartmentation, and metabolism of homoserine was characterized in two strains of meristematic higher plant cells, the dicotyledonous sycamore (Acer pseudoplatanus) and the monocotyledonous weed Echinochloa colonum. Homoserine is an intermediate in the synthesis of the aspartate-derived amino acids methionine, threonine (Thr), and isoleucine. Using 13C-nuclear magnetic resonance, we showed that homoserine actively entered the cells via a high-affinity proton-symport carrier (K(m) approximately 50-60 micromolar) at the maximum rate of 8 +/- 0.5 micromol h-1 g-1 cell wet weight, and in competition with serine or Thr. We could visualize the compartmentation of homoserine, and observed that it accumulated at a concentration 4 to 5 times higher in the cytoplasm than in the large vacuolar compartment. 31P-nuclear magnetic resonance permitted us to analyze the phosphorylation of homoserine. When sycamore cells were incubated with 100 micromolar homoserine, phosphohomoserine steadily accumulated in the cytoplasmic compartment over 24 h at the constant rate of 0.7 micromol h-1 g-1 cell wet weight, indicating that homoserine kinase was not inhibited in vivo by its product, phosphohomoserine. The rate of metabolism of phosphohomoserine was much lower (0.06 micromol h-1 g-1 cell wet weight) and essentially sustained Thr accumulation. Similarly, homoserine was actively incorporated by E. colonum cells. However, in contrast to what was seen in sycamore cells, large accumulations of Thr were observed, whereas the intracellular concentration of homoserine remained low, and phosphohomoserine did not accumulate. These differences with sycamore cells were attributed to the presence of a higher Thr synthase activity in this strain of monocot cells

  12. Impact of interspecific competition and drought on the allocation of new assimilates in trees.

    Hommel, R; Siegwolf, R; Zavadlav, S; Arend, M; Schaub, M; Galiano, L; Haeni, M; Kayler, Z E; Gessler, A

    2016-09-01

    In trees, the interplay between reduced carbon assimilation and the inability to transport carbohydrates to the sites of demand under drought might be one of the mechanisms leading to carbon starvation. However, we largely lack knowledge on how drought effects on new assimilate allocation differ between species with different drought sensitivities and how these effects are modified by interspecific competition. We assessed the fate of (13) C labelled assimilates in above- and belowground plant organs and in root/rhizosphere respired CO2 in saplings of drought-tolerant Norway maple (Acer platanoides) and drought-sensitive European beech (Fagus sylvatica) exposed to moderate drought, either in mono- or mixed culture. While drought reduced stomatal conductance and photosynthesis rates in both species, both maintained assimilate transport belowground. Beech even allocated more new assimilate to the roots under moderate drought compared to non-limited water supply conditions, and this pattern was even more pronounced under interspecific competition. Even though maple was a superior competitor compared to beech under non-limited soil water conditions, as indicated by the changes in above- and belowground biomass of both species in the interspecific competition treatments, we can state that beech was still able to efficiently allocate new assimilate belowground under combined drought and interspecific competition. This might be seen as a strategy to maintain root osmotic potential and to prioritise root functioning. Our results thus show that beech tolerates moderate drought stress plus competition without losing its ability to supply belowground tissues. It remains to be explored in future work if this strategy is also valid during long-term drought exposure. PMID:27061772

  13. Aboveground Net Primary Productivity in a Riparian Wetland Following Restoration of Hydrology.

    Koontz, Melissa; Lundberg, Christopher; Lane, Robert; Day, John; Pezeshki, Reza

    2016-01-01

    This research presents the initial results of the effects of hydrological restoration on forested wetlands in the Mississippi alluvial plain near Memphis, Tennessee. Measurements were carried out in a secondary channel, the Loosahatchie Chute, in which rock dikes were constructed in the 1960s to keep most flow in the main navigation channel. In 2008-2009, the dikes were notched to allow more flow into the secondary channel. Study sites were established based on relative distance downstream of the notched dikes. Additionally, a reference site was established north of the Loosahatchie Chute where the dikes remained unnotched. We compared various components of vegetation composition and productivity at sites in the riparian wetlands for two years. Salix nigra had the highest Importance Value at every site. Species with minor Importance Values were Celtis laevigata, Acer rubrum, and Plantanus occidentalis. Productivity increased more following the introduction of river water in affected sites compared to the reference. Aboveground net primary productivity was highest at the reference site (2926 ± 458.1 g·m(-2)·year(-1)), the intact site; however, there were greater increase at the sites in the Loosahatchie Chute, where measurements ranged from 1197.7 ± 160.0 g m(-2)·year(-1)·to 2874.2 ± 794.0 g·m(-2)·year(-1). The site furthest from the notching was the most affected. Pulsed inputs into these wetlands may enhance forested wetland productivity. Continued monitoring will quantify impacts of restored channel hydrology along the Mississippi River. PMID:26861409

  14. 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

    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

  15. BIFoR FACE: A Free-Air Carbon Dioxide Enrichment (FACE) facility in old-growth temperate deciduous woodland

    MacKenzie, Rob; Thomas, Rick; Ellsworth, David; Hemming, Debbie; Crous, Kristine; Blaen, Phillip; Poynter, Alex; Blenkhorn, Daniel; Pope, Francis

    2016-04-01

    The Birmingham Institute of Forest research (BIFoR) focuses on fundamental physical, biological, ecological, social and cultural research of direct relevance to forested landscapes worldwide. A core platform for BIFoR is a Free-Air Carbon Dioxide Enrichment (FACE) facility, with which we study the ten-year response of a mature temperate deciduous forest ecosystem to a 150-ppmv step-change in atmospheric [CO2]. BIFoR FACE is being established in Mill Haft, a mature (~150 year-old) oak (Quercus robur) and hazel (Corylus avellana) coppice-with-standards woodland in central England, UK. The facility enables elevated CO2 (eCO2) treatments to be introduced in 30 m diameter rings (3 treatment plots, 3 fully-replicated control plots, and 3 unmodified ambient controls). Primary research questions focus on carbon uptake and storage, corresponding nutrient limitations, and biodiversity and ecosystem responses to elevated CO2. Here we describe the facility and experimental design, and present baseline data collected through the growing season of 2015. These data include: biophysical tree properties; atmospheric CO2/H2O fluxes; airborne and ground laser scatterometry; leaf area index; geophysical survey data; canopy phenology; soil and water chemical and physical properties; and invertebrate surveys. Data from an intensive campaign conducted during august 2015 are also shown, including in- and above- canopy characterisation of biogenic VOCs using a Proton Transfer Reaction Mass Spectrometer, aerosol loading including bioaerosols, and air quality. Further campaign results are presented from leaf level photosynthetic carbon-dioxide response curve (A/Ci) performed at different canopy heights on oak trees, and on the dominant understory species - hazel and sycamore (Acer pseudoplatanus) across the site. BIFoR FACE is intended to be an international facility for forest science - ideas for collaborations are encouraged. Please see http

  16. The Little Ice Age and its Spatial Variability across the Balkans

    Kulkarni, C.; Peteet, D. M.; Boger, R. A.

    2015-12-01

    Using biological proxies (pollen, spores, and charcoal), geochemical signals through X-ray fluorescence, and AMS 14C based chronology, we present a correlation between two new high resolution Little Ice Age (LIA) records from the Central Balkans that are part of one of the least studied regions of Europe. The sediments extracted from a western sinkhole and central Serbian oxbow lake are analyzed at 8-10-cm intervals to capture the nature and magnitude of the LIA at a resolution of 20 years. During the 15th-19th CE, indigenous tree (e.g. Quercus, Acer, Pinus) and herbaceous (e.g. Poaceae, Chenopodiaceae, Artemisia) pollen from these records demonstrate fluctuations in woodland-grassland dynamics. While tree populations from Central Serbia remain comparatively stable (40-60%), the trees of western Serbia vacillate drastically between 15% and 50%. Similarly, central Serbian grasses show variations of ~18-36% whereas the western Serbian grass populations exhibit abrupt oscillations between high (55%) and low (19%) percentages. As a proxy for surface erosion and clastic input into the lakes, the 1-cm resolution potassium and titanium counts are in strong agreement with varying herbaceous taxa. These variations in ecological signals across the cores can account for local factors including altitude, terrain exposure, soils etc., however, the dynamic human component of the landscape is evident through crop pollen (e.g. Cerealia, Juglans) and microscopic charcoal highlighting the dominant role of people in ecological changes. Although the two sites show certain differences in charcoal concentration, extremely high charcoal indicates accelerated land clearance between the 15th and 17th CE. Until the beginning of 18th CE, the cultivars (e.g. Secale, Triticum) occur with very low percentages and then peak to suggest improved agriculture in the region. In the post-LIA era, the 20th CE exhibits increased arboreal percentages and declining grasslands in both the two Central

  17. General functions to transform associate data to host data, and their use in phylogenetic inference from sequences with intra-individual variability

    Grimm Guido W

    2008-03-01

    Full Text Available Abstract Background Amongst the most commonly used molecular markers for plant phylogenetic studies are the nuclear ribosomal internal transcribed spacers (ITS. Intra-individual variability of these multicopy regions is a very common phenomenon in plants, the causes of which are debated in literature. Phylogenetic reconstruction under these conditions is inherently difficult. Our approach is to consider this problem as a special case of the general biological question of how to infer the characteristics of hosts (represented here by plant individuals from features of their associates (represented by cloned sequences here. Results Six general transformation functions are introduced, covering the transformation of associate characters to discrete and continuous host characters, and the transformation of associate distances to host distances. A pure distance-based framework is established in which these transformation functions are applied to ITS sequences collected from the angiosperm genera Acer, Fagus and Zelkova. The formulae are also applied to allelic data of three different loci obtained from Rosa spp. The functions are validated by (1 phylogeny-independent measures of treelikeness; (2 correlation with independent host characters; (3 visualization using splits graphs and comparison with published data on the test organisms. The results agree well with these three measures and the datasets examined as well as with the theoretical predictions and previous results in the literature. High-quality distance matrices are obtained with four of the six transformation formulae. We demonstrate that one of them represents a generalization of the Sørensen coefficient, which is widely applied in ecology. Conclusion Because of their generality, the transformation functions may be applied to a wide range of biological problems that are interpretable in terms of hosts and associates. Regarding cloned sequences, the formulae have a high potential to

  18. Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle.

    Najihah Musa

    Full Text Available The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management.

  19. Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle

    Musa, Najihah; Andersson, Klas; Burman, Joseph; Andersson, Fredrik; Hedenström, Erik; Jansson, Nicklas; Paltto, Heidi; Westerberg, Lars; Winde, Inis; Larsson, Mattias C.; Bergman, Karl-Olof; Milberg, Per

    2013-01-01

    The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak) was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata) were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management. PMID:23840415

  20. El Lago de Tota

    Borrero H. José I.

    1963-06-01

    Full Text Available Puesto que el lago de Tola constituye hoy en día la única fuente de abastecimiento de agua para nuestra máxima industria nacional, como es Acerías de Paz del Río, porque esta industria depende en un ciento por ciento del lago de Tota para su desarrollo actual y ensanches futuros, según concepto de sus directivas además por ser este un lugar de incomparable belleza al cual debe dársele la importancia que merece, se ha resuelto escribir estas líneas, en las cuales el lector encontrará esbozados en la forma más sucinta posible una serie de hechos que a no dudar todos hemos observado al visitar el lago. No se pretende que este pequeño escrito abarque todo el problema que es de por sí muy vasto y que posiblemente ha sido tratado ya antes con mayor propiedad, pero sí se espera que produzca en cada uno de los lectores una reacción que sea lo suficientemente grande para que logre convertirlos en admiradores de Tota por consiguiente en sus perennes defensores. No tratamos tampoco de inculpar a nadie y menos a ninguna de las entidades nacionales responsables de la conservación de nuestros recursos naturales, sino simplemente de alertar a todos los directivos de esas entidades para que de común acuerdo logremos salvar el Lago de Tota.

  1. Study of patients of road traffic accidents a rriving in emergency department [ED] of V.S hospital at Ahmedabad city, single centre pilot study.

    Aharnish Shah

    2014-07-01

    Full Text Available Objectives of the study According to the latest world status report on road safety released by WHO, we are now the world leaders in road traffic accident rate & related mortality. Our study intends to find out the epidemiological factors, risk factors, use of safety measures, compliance with traffic laws, presenting injuries & ED intervention required, in patients with road traffic accidents. Materials & methods Our study is a cross sectional observational study in which data was obtained from 150 patients of road traffic accidents arriving at any time to emergency department. Collected data included information about basic details, basic crash characteristics, risk factors, use of safety measures, injuries sustained, ED intervention required & disposition. Results Approximately 77% of the patients belong to 11-50 yr age group. The most common time of RTA is between 6 am to 12 noon [36.67%]. However accidents requiring admission were more during night time [62.74%]. Innocent passengers & pedestrians contributed to 41% of the accident cases. Non compliance with traffic laws & safety measures like driving without license [20%], using mobile phones while driving [10%], not using headlights at night [26%], not using seatbelts [80%], not using helmets [91%], etc were found in a substantial number of cases. Intracranial bleed & skull fractures were significantly (31.2% v/s 0% more in drivers without helmets than those with helmets. ED intervention required in decreasing order were dressing ( 38%, laceration repair (27.33%, splinting (24%, crash intubation (10%, ICD (2.66%. Conclusion: Well equipped secondary & tertiary level trauma centres, specially dedicated to management of trauma patients, with a proper triage plan, are necessary for proper management of trauma patients & better utilisation of resources. Our study shows that an ER physician should be trained in l aceration repair, dressing, splint/slab application, fracture/dislocation reduction

  2. Predicting tree biomass growth in the temperate-boreal ecotone: Is tree size, age, competition, or climate response most important?

    Foster, Jane R; Finley, Andrew O; D'Amato, Anthony W; Bradford, John B; Banerjee, Sudipto

    2016-06-01

    As global temperatures rise, variation in annual climate is also changing, with unknown consequences for forest biomes. Growing forests have the ability to capture atmospheric CO2 and thereby slow rising CO2 concentrations. Forests' ongoing ability to sequester C depends on how tree communities respond to changes in climate variation. Much of what we know about tree and forest response to climate variation comes from tree-ring records. Yet typical tree-ring datasets and models do not capture the diversity of climate responses that exist within and among trees and species. We address this issue using a model that estimates individual tree response to climate variables while accounting for variation in individuals' size, age, competitive status, and spatially structured latent covariates. Our model allows for inference about variance within and among species. We quantify how variables influence aboveground biomass growth of individual trees from a representative sample of 15 northern or southern tree species growing in a transition zone between boreal and temperate biomes. Individual trees varied in their growth response to fluctuating mean annual temperature and summer moisture stress. The variation among individuals within a species was wider than mean differences among species. The effects of mean temperature and summer moisture stress interacted, such that warm years produced positive responses to summer moisture availability and cool years produced negative responses. As climate models project significant increases in annual temperatures, growth of species like Acer saccharum, Quercus rubra, and Picea glauca will vary more in response to summer moisture stress than in the past. The magnitude of biomass growth variation in response to annual climate was 92-95% smaller than responses to tree size and age. This means that measuring or predicting the physical structure of current and future forests could tell us more about future C dynamics than growth responses

  3. Air pollution assessment based on elemental concentration of leaves tissue and foliage dust along an urbanization gradient in Vienna

    Foliage dust contains heavy metal that may have harmful effects on human health. The elemental contents of tree leaves and foliage dust are especially useful to assess air environmental pollution. We studied the elemental concentrations in foliage dust and leaves of Acer pseudoplatanus along an urbanization gradient in Vienna, Austria. Samples were collected from urban, suburban and rural areas. We analysed 19 elements in both kind of samples: aluminium, barium, calcium, copper, iron, potassium, magnesium, sodium, phosphor, sulphur, strontium and zinc. We found that the elemental concentrations of foliage dust were significantly higher in the urban area than in the rural area for aluminium, barium, iron, lead, phosphor and selenium. Elemental concentrations of leaves were significantly higher in urban than in rural area for manganese and strontium. Urbanization changed significantly the elemental concentrations of foliage dust and leaves and the applied method can be useful for monitoring the environmental load. - Highlights: → We studied the elements in dust and leaves along an urbanization gradient, Austria. → We analysed 19 elements: Al, Ba, Ca, Cd, Cu, Fe, K, Mg, Na, P, Pb, S, Sr and Zn. → Elemental concentrations were higher in urban area than in the rural area. → Studied areas were separated by CDA based on the elemental concentrations. → Dust and leaves can be useful for monitoring the environmental load. - Studying the elements (Al, Ba, Ca, Cu, Fe, K, Mg, Na, P, S, Sr, Zn) in dust and leaves along an urbanization gradient in Wien, Austria we found that the elemental concentrations of foliage dust were significantly higher in the urban area than in the rural area for Al, Ba, Fe, Pb, P and Se, and concentrations of leaves were significantly higher in urban than in rural area for Mn and Sr.

  4. A floristic survey of the Hyrcanian forests in Northern Iran, using two lowland-mountain transects

    Alireza Naqinezhad; Hassan Zare-Maivan; Hamid Gholizadeh

    2015-01-01

    We investigated the floristic composition of the Hyrcanian forests and the related forest-steppe ecotone in Northern Iran by using two long ecological transects, from lowland to upper mountain areas. The study was conducted during 2008 and 2009 and yielded the identification of 395 plant taxa belonging to 233 genera and 78 families. Dicots with 300 taxa were the richest groups of the flora, followed by monocots with 75 taxa, pteridophytes with 18 species, and gymnosperms with two species. The largest families were Asteraceae (33 taxa); Rosaceae (32 taxa); and Poa-ceae (30 taxa), and the most diverse genera included Carex (15 taxa); Alchemilla (7 taxa); and Poa, Geranium and Acer (6 taxa each). Hemicryptophytes were the most dominant life forms in the area (40%); followed by geo-phytes (31.4%); phanerophytes (15.4%); therophytes (11.4%);and chamaephytes (1.8%). Phytogeographically, Euro-Siberian/Irano-Turanian elements (86 taxa, 21.8%) and Euro-Siberian elements (85 taxa, 21.5%) were the most common chorotypes in the area. Out of 395 taxa, 66 taxa (16.7%) were endemics and subendemics in Iran, of which 26 taxa were exclusively endemics of Iran. According to the IUCN Red List Categories, 48 threatened plant taxa were found in the study area. Plant diversity, life form, and chorotypes in the current study were compared with similar transect studies in other areas of the Hyrcanian forests and in different altitudinal belts, using Sørenson similarity indices. Floristic composition of the surveyed transects demonstrated almost 50% similarity between them.

  5. Ionic liquids influence on the surface properties of electron beam irradiated wood

    Highlights: • Wood veneers impregnated with three imidazolium-based ionic liquids and irradiated with electron beam were studied by FTIR-ATR, SEM/EDX, AFM, contact angle and image analysis. • ILs preserve the surface properties of the wood (surface energy, roughness, color) upon irradiation, in comparison with the reference wood, but the surface composition is changed by treatment with IL-s, mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. • Under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface. - Abstract: In this paper, the influence of three imidazolium-based ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-hexyl-3-methylimidazolium chloride) on the structure and surface properties of sycamore maple (Acer pseudoplatanus) veneers submitted to electron beam irradiation with a dose of 50 kGy has been studied by using Fourier transform infrared spectroscopy, as well as image, scanning electron microscopy/SEM/EDX, atomic force microscopy and contact angle analysis. The experimental results have proven that the studied ionic liquids determine a better preservation of the structural features of wood (cellulose crystallinity index and lignin concentration on the surface) as well as some of surface properties such as surface energy, roughness, color upon irradiation with electron beam, in comparison with the reference wood, but surface composition is changed by treatment with imidazolium-based ionic liquids mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. Also, under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface

  6. [Composition and seasonal dynamics of litter falls in a broad-leaved Korean pine (Pinus koraiensis) mixed forest in Changbai Mountains, Northeast China].

    Yuan, Zuo-qiang; Li, Bu-hang; Bai, Xue-jiao; Lin, Fei; Shi, Shuai; Ye, Ji; Wang, Xu-gao; Hao, Zhan-qing

    2010-09-01

    In order to understand the composition and spatiotemporal dynamics of the litter falls at community level in a broad-leaved Korean pine mixed forest in Changbai Mountains, litter falls were collected from 150 containers in a 25 hm2 permanent plot in 2008. The leaf litters in the containers were from 35 tree species, accounting for 67.3% of the total number (52) of the tree species with DBH > or =1 cm in the plot. The litter falls had a weight 29.39 kg, equivalent to 3918.4 kg x hm(-2) among which, broad leaves, miscellany, needle leaves, and branches occupied 61.7%, 18.0%, 11.7%, and 8.6%, respectively. About 83.8% of the broad leaves were from Tilia amurensis, Fraxinus mandshurica, Quercus mongolica, Acer mono, and Ulmus japonica. The litter falls showed an evident seasonal dynamics, with the peaks occurred from 13 September to 10 October, e.g., the litter falls from T. amurensis and Pinus koraiensis peaked in 13-26 September, while those from Q. mongolica, U. japonica, and A. pseudo-sieboldianum peaked in 27 September to 10 October. There was a great difference in the mass of the litter falls among the containers, e.g., with 150-200 g litters in 68 containers and >500 g litters in 1 container. The species number of the litter falls in a container was 18 in maximum, and was 12 in common (32 containers). Litter falls mass was positively proportional to the sum of the basal area at breast height of parent trees in the plot, and the amount of the litter falls in the containers was related with the locations of the containers, exhibiting an evident spatial heterogeneity in the plot. PMID:21265134

  7. Tree Nonstructural Carbohydrate Reserves Across Eastern US Temperate Forests

    Mantooth, J.; Dietze, M.

    2015-12-01

    Understanding the roles, importance, and dynamics of tree non-structural carbohydrates (NSCs) is currently an active area of research. The question of how the relationships between NSCs, growth, and mortality can be used to develop more accurate projections of forest dynamics is central to this research. To begin to address this question, we have asked an even more fundamental question: How much are trees allocating carbon to storage, in the form of NSCs, versus new growth? Ecological theory predicts that there should be trade-offs between different plant life history strategies provided that there are the carbon mass-balance constraints to enforce these trade-offs. Current data on tree NSCs lack the spatial and taxonomic extent required to properly address this question. Therefore, we established a network of forest inventory plots at ten sites across the eastern US and measured growth in adult trees using increment cores and repeat measures of diameter at breast height (DBH). Increment cores were also used to measure sapwood NSCs. We hypothesized that across the eastern US, shade tolerant species, e.g. Sugar Maple (Acer saccharum) have the largest NSC reserves and that shade intolerant species have the lowest reserves. We also hypothesized that NSC reserves increase with temperature and precipitation, as with growth, and that within species NSC reserves increase with growth rate. Initial analyses of tree NSCs indicates that trees of intermediate shade tolerance, e.g. Red Oak (Quercus rubra) have the highest concentrations of sapwood NSCs, and among the highest growth rates. Across the entire study region, NSC concentrations are positively correlated with tree size and growth rate. Within species, NSC concentrations are also positively correlated with growth rate. Across functional groups healthy individuals have significantly higher sapwood NSC concentrations than visibly stressed individuals. There are also significantly lower NSC concentrations in sapwood of

  8. Survivors, not invaders, control forest development following simulated hurricane.

    Plotkin, Audrey Barker; Foster, David; Carlson, Joel; Magill, Alison

    2013-02-01

    Wind disturbance profoundly shapes temperate forests but few studies have evaluated patterns and mechanisms of long-term forest dynamics following major windthrows. In 1990, we initiated a large hurricane simulation experiment in a 0.8-ha manipulation (pulldown) and 0.6-ha control area of a maturing Quercus rubra--Acer rubrum forest in New England. We toppled 276 trees in the pulldown, using a winch and cable, in the northwesterly direction of natural treefall from major hurricanes. Eighty percent of canopy trees and two-thirds of all trees > or = 5 cm dbh (diameter at breast height) suffered direct and indirect damage. We used 20 years of measurements to evaluate the trajectory and mechanisms of forest response after intense disturbance. Based on the patch size and disturbance magnitude, we expected pioneer tree and understory species to drive succession. The first decade of analyses emphasized tree seedling establishment and sprouting by damaged trees as the dominant mechanisms of forest recovery in this extensive damaged area. However, despite 80% canopy damage and 8000-m2 patch size, surviving overstory and advance regeneration controlled longer-term forest development. Residual oaks make up 42% of stand basal area after 20 years. The new cohort of trees, dominated by black birch advance regeneration, contributes 30% of stand basal area. There were shifts in understory vegetation composition and cover, but few species were gained or lost after 20 years. Stand productivity rebounded quickly (litterfall recovered to pre-disturbance levels in six years), but we predict that basal area in the pulldown will lag behind the control (which gained 6 m2/ha over 20 years) for decades to come. This controlled experiment showed that although the scale and intensity of damage were great, abundant advance regeneration, understory vegetation, and damaged trees remained, allowing the forest to resist changes in ecosystem processes and invasion by new species. PMID:23691660

  9. Changes in radiocesium contamination from Fukushima in foliar parts of 10 common tree species in Japan between 2011 and 2013.

    Yoshihara, Toshihiro; Matsumura, Hideyuki; Tsuzaki, Masaharu; Wakamatsu, Takashi; Kobayashi, Takuya; Hashida, Shin-Nosuke; Nagaoka, Toru; Goto, Fumiyuki

    2014-12-01

    Yearly changes in radiocesium ((137)Cs) contamination, primarily due to the Fukushima accident of March 2011, were observed in the foliar parts of 10 common woody species in Japan (Chamaecyparis obtusa, Cedrus deodara, Pinus densiflora, Cryptomeria japonica, Phyllostachys pubescens, Cinnamomum camphora, Metasequoia glyptostroboides, Prunus × yedoensis, Acer buergerianum, and Aesculus hippocastanum). The samples were obtained from Abiko (approximately 200 km SSW of the Fukushima Dai-ichi Nuclear Power Plant) during each growing season between 2011 and 2013, and the foliar parts were examined based on their year of expansion and location in each trees. The radiocesium concentrations generally decreased with time; however, the concentrations and rates of decrease varied among species, age of foliar parts, and locations. The radiocesium concentrations in the 2012 current-year foliar parts were 29%-220% of those from 2011, while those from 2013 fell to between 14% and 42% of the 2011 values. The net decontamination in the foliage was higher in evergreen species than in deciduous species. The radiocesium concentrations in the upper foliar parts were higher than those in the lower parts particularly in C. japonica. In addition, the radiocesium concentrations were higher in the current-year foliar parts than in the 1-year-old foliar parts, particularly in 2013. Thus, the influence of the direct deposition of the fallout was reduced with time, and the translocation ability of radiocesium from old to new tissues became more influential. Similar to the behavior of potassium in trees, Cs redistribution probably occurred primarily due to internal nutrient translocation mechanisms. PMID:25261868

  10. Chemometrics in biomonitoring: Distribution and correlation of trace elements in tree leaves.

    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

  11. Transpiration of urban trees and its cooling effect in a high latitude city

    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.

  12. Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle.

    Musa, Najihah; Andersson, Klas; Burman, Joseph; Andersson, Fredrik; Hedenström, Erik; Jansson, Nicklas; Paltto, Heidi; Westerberg, Lars; Winde, Inis; Larsson, Mattias C; Bergman, Karl-Olof; Milberg, Per

    2013-01-01

    The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak) was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata) were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management. PMID:23840415

  13. Аллелопатическая активность листового опада древесных растений, почвы и копролитов в парках г. Днепропетровск

    Анжелина Илларионовна Крючкова; Юрий Люцинович Кульбачко

    2014-01-01

    В работе рассматривается влияние аллелопатических свойств опада древесных растений и трофометаболической деятельности дождевых червей (Lumbricidae) на аллелопатические свойства почвы под древесными породами Acer platanoides L., Aesculus hippocastanum L., Ulmus minor Mill. в парках г. Днепропетровск. Установлено, что трофометаболическая деятельность червей положительно влияет на аллелопатический статус почв....

  14. Characterisation of airborne particulates and associated trace metals deposited on tree bark by ICP-OES, ICP-MS, SEM-EDX and laser ablation ICP-MS

    Suzuki, Keiko

    Particulate matter accumulated on tree bark specimens was examined in order to investigate its potential use as a natural monitor to study the impact on local atmospheric conditions. Tree bark from sargent cherry ( Prunus sargentii) and sugar maple ( Acer saccharum Marsh) trees was collected from four locations: Drax (North Yorkshire), Darley Dale (Derbyshire), Galway (Ireland) and Tristan da Cunha. Particulates accumulated on tree bark were prepared for analysis using a microwave-assisted HNO 3 digestion. The bulk elemental content was determined by inductively coupled plasma optical emission spectrometry (ICP-OES) and trace metals were analysed by inductively coupled plasma mass spectrometry (ICP-MS). Analysis of bulk tree bark samples revealed that the highest mean Pb concentration was obtained in Darley Dale samples, 1069 ng g -1, with 147 and 3.2 ng g -1 Pb in Drax and Galway samples, respectively. In Tristan da Cunha samples 0.12 ng g -1 of Pb was detected. Pb, As, Cr, Sb, Sn and Zn were enriched by factors of 10-8650 relative to the background elemental abundance in tree bark obtained from Tristan da Cunha. Particulates accumulated on the tree bark were characterised by SEM-EDX and LA-ICP-MS to provide information on the particle composition and morphology. This study supports the suggestion that the major particulate sources are high-temperature combustion processes. Direct analysis by LA-ICP-MS revealed the potential of this alternative method to investigate the distribution of suspended particulates and their elemental association on the bark specimen.

  15. Modifying woody plants for efficient conversion to liquid and gaseous fuels

    Dinus, R.J.; Dimmel, D.R.; Feirer, R.P.; Johnson, M.A.; Malcolm, E.W. (Institute of Paper Science and Technology, Atlanta, GA (USA))

    1990-07-01

    The Short Rotation Woody Crop Program (SRWCP), Department of Energy, is developing woody plant species as sources of renewable energy. Much progress has been made in identifying useful species, and testing site adaptability, stand densities, coppicing abilities, rotation lengths, and harvesting systems. Conventional plant breeding and intensive cultural practices have been used to increase above-ground biomass yields. Given these and foreseeable accomplishments, program leaders are now shifting attention to prospects for altering biomass physical and chemical characteristics, and to ways for improving the efficiency with which biomass can be converted to gaseous and liquid fuels. This report provides a review and synthesis of literature concerning the quantity and quality of such characteristics and constituents, and opportunities for manipulating them via conventional selection and breeding and/or molecular biology. Species now used by SRWCP are emphasized, with supporting information drawn from others as needed. Little information was found on silver maple (Acer saccharinum), but general comparisons (Isenberg 1981) suggest composition and behavior similar to those of the other species. Where possible, conclusions concerning means for and feasibility of manipulation are given, along with expected impacts on conversion efficiency. Information is also provided on relationships to other traits, genotype X environment interactions, and potential trade-offs or limitations. Biomass productivity per se is not addressed, except in terms of effects that may by caused by changes in constituent quality and/or quantity. Such effects are noted to the extent they are known or can be estimated. Likely impacts of changes, however effected, on suitability or other uses, e.g., pulp and paper manufacture, are notes. 311 refs., 4 figs., 9 tabs.

  16. Soil magnetic susceptibility reflects soil moisture regimes and the adaptability of tree species to these regimes

    Wang, J.-S.; Grimley, D.A.; Xu, C.; Dawson, J.O.

    2008-01-01

    Flooded, saturated or poorly drained soils are frequently anaerobic, leading to dissolution of the strongly magnetic minerals, magnetite and maghemite, and a corresponding decrease in soil magnetic susceptibility (MS). In this study of five temperate deciduous forests in east-central Illinois, USA, mean surface soil MS was significantly higher adjacent to upland tree species (31 ?? 10-5 SI) than adjacent to floodplain or lowland tree species (17 ?? 10-5 SI), when comparing regional soils with similar parent material of loessal silt. Although the sites differ in average soil MS for each tree species, the relative order of soil MS means for associated tree species at different locations is similar. Lowland tree species, Celtis occidentalis L., Ulmus americana L., Acer saccharinum L., Carya laciniosa (Michx. f.) Loud., and Fraxinus pennsylvanica Marsh. were associated with the lowest measured soil MS mean values overall and at each site. Tree species' flood tolerance rankings increased significantly, as soil MS values declined, the published rankings having significant correlations with soil MS values for the same species groups. The three published classifications of tree species' flood tolerance were significantly correlated with associated soil MS values at all sites, but most strongly at Allerton Park, the site with the widest range of soil drainage classes and MS values. Using soil MS measurements in forests with soil parent material containing similar initial levels of strongly magnetic minerals can provide a simple, rapid and quantitative method to classify soils according to hydric regimes, including dry conditions, and associated plant composition. Soil MS values thus have the capacity to quantify the continuum of hydric tolerances of tree species and guide tree species selection for reforestation. ?? 2007 Elsevier B.V. All rights reserved.

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

    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

  18. Photostabilization of the botanical insecticide azadirachtin in the presence of lecithin as UV protectant

    The phytochemical insecticide, azadirachtin (AZ), undergoes UV‐induced photodegradation. Using the isomer AZ‐A as a standard, its photochemical stability was studied with and without adding lecithin surfactant as a UV protectant. Standard solutions of pure AZ‐A and Margosan‐O® were prepared in methanol‐hexane with (AZ‐A:lecithin, 1:2 by weight) and without lecithin, applied separately onto glass plates and maple (Acer L.) foliage and exposed to radiant energy under controlled conditions. Noticeable photostabilization of AZ‐A was achieved in the samples containing lecithin compared to AZ‐A samples without the lecithin additive. First‐order kinetic evaluation of the data showed that the DTy50 (half‐life) and C (rate constant) values for AZ‐A with and without lecithin on glass plates were 5.68 d and 0.122, and 5.42 d and 0.128, respectively. The corresponding values for the Margosan‐0 formulation were 7.37 d and 0.094, and 6.24 d and 0.111. The DT50 and C values for the pure AZ‐A on maple foliage with and without lecithin were 8.77 d and 0.079, and 6.54 d and 0.106, respectively. The corresponding values for the Margosan‐0 formulation on foliage were 8.35 d and 0.083, and 7.45 d and 0.093. The kinetic data gave quantitative information regarding the photostabilization of AZ‐A in the presence of lecithin. Good UV protection can only be achieved if the additive has the matching Xmax of AZ‐A. The mechanism of photostabilization of AZ‐A in the presence of lecithin was due to either energy transfer from the excited AZ‐A to lecithin and/or competitive absorption of UV photons by the latter

  19. Climate change triggers effects of fungal pathogens and insect herbivores on litter decomposition

    Butenschoen, Olaf; Scheu, Stefan

    2014-10-01

    Increasing infestation by insect herbivores and pathogenic fungi in response to climate change will inevitably impact the amount and quality of leaf litter inputs into the soil. However, little is known on the interactive effect of infestation severity and climate change on litter decomposition, and no such study has been published for deciduous forests in Central Europe. We assessed changes in initial chemical quality of beech (Fagus sylvatica L.) and maple litter (Acer platanoides L.) in response to infestation by the gall midge Mikiola fagi Hart. and the pathogenic fungus Sawadaea tulasnei Fuckel, respectively, and investigated interactive effects of infestation severity, changes in temperature and soil moisture on carbon mineralization in a short-term laboratory study. We found that infestation by the gall midge M. fagi and the pathogenic fungus S. tulasnei significantly changed the chemical quality of beech and maple litter. Changes in element concentrations were generally positive and more pronounced, and if negative less pronounced for maple than beech litter most likely due to high quality fungal tissue remaining on litter after abscission. More importantly, alterations in litter chemical quality did not translate to distinct patterns of carbon mineralization at ambient conditions, but even low amounts of infested litter accelerated carbon mineralization at moderately increased soil moisture and in particular at higher temperature. Our results indicate that insect herbivores and fungal pathogens can markedly alter initial litter chemical quality, but that afterlife effects on carbon mineralization depend on soil moisture and temperature, suggesting that increased infestation severity under projected climate change potentially increases soil carbon release in deciduous forests in Central Europe.

  20. Impacts of Invasive Pests on Forest Carbon and Nitrogen Dynamics

    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.

  1. Temporal Persistence of Point Throughfall in a Deciduous Forest

    Carlyle-Moses, D. E.

    2011-12-01

    For 28 rainfall events with a cumulative depth of 259.3mm, throughfall (TF) was measured using 85 stationary cylindrical gauges (catch area = 0.067 m^2 each) in a deciduous forest comprised of red oak (Quercus rubra L.), sugar maple (Acer saccharum Marsh.) and American beech (Fagus gradifolia Ehrh.) under growing season conditions. For rainfalls in which all gauges received TF the ratio between the maximum and minimum point TF was 11.2 for rainfalls MAD)^-1, where TFn represents the normalized TF value, TFi and TFMedian are the point TF at gauge i (mm) and median point TF (mm) for all gauges, respectively, and MAD is the mean absolute difference of all gauge catches from TFMedian (mm). Analyses of the temporal stability of TFn and backwards step-wise multiple regression of TFn versus rainfall depth (mm) and mean rainfall intensity (mm h^-1) were conducted revealing a complex TF spatio-temporal pattern below the canopy. Forty-one of the 85 gauges (48 %) had temporally persistent catches that were significantly (p ≤ 0.05) smaller (21 %) or larger (27 %) than the median. Many gauges that had a significant temporal persistence of TFn also exhibited significant (p ≤ 0.10) weak (r^2 0.153 had mean TFn values > 0. There was no significant difference (p < 0.05) between the stand average pf of 0.162 ± 0.07 and the threshold pf value of 0.153. The change in the spatial pattern of TF through time was evaluated using Spearman's rank correlation coefficient values of all possible event pairings as the dependent variable and the temporal lag (days), difference in rainfall depth, and difference in mean rainfall intensity as independent variables. Explanations as to the spatio-temporal behaviour of TFn are given and the implications of the study findings on TF sampling and simulation are discussed.

  2. How to help woody plants to overcome drought stress?-a control study of four tree species in Northwest China.

    Liu, Xiaozhen; Zhang, Shuoxin

    2010-05-01

    Water is essential for plants and involves most physical and chemical processes within their lifecycles. Drought stress is a crucial limiting factor for plant growth and production. 48% of the land in China is arid and semi-arid, and non-irrigated land occupies approximately 51.9% of the total cultivated areas. Therefore, studies on plant drought resistant mechanisms have great significance for improving water use efficiency and thus increasing productivity of economical plants. Prior research has shown that the application of nitrogenous fertilizer affects the drought-resistant characteristics of plants. This study aimed to reveal the effect of nitrogenous fertilizer on physiological aspects and its impact on the drought resistance of four tree species (Robinia pseudoacacia L., Ligustrum lucidum Ait., Acer truncatum Bge. and Ulmus pumila L. ) in northwest China. Three levels of nitrogen fertilization (46% N based of urea adjusted to: 5g/15g soil, 15g/15g soil and 25g/15g soil) and an additional control study were applied to 2-year-old well-grown seedlings under drought conditions (30% field moisture capacity). Stomatal conductance, transpiration rate and net photosynthetic rate were measured by a LI-6400 photosynthesis system, while water use efficiency was calculated from net photosynthesis rate and transpiration rate. The results revealed that as the amount of urea applied was raised, stomatal conductance, transpiration rate and net photosynthetic rate decreased significantly, and thus water use efficiency significantly increased. It is therefore concluded that the application of nitrogenous fertilizer regulated physiological parameters by reducing stomata conductance to improve water use efficiency. In addition, among the four tree species, U. pumila had the maximum value of water use efficiency under the same drought condition. The outcome of this study provides a guided option for forest management in arid and semi-arid areas of northwest China.

  3. Uses of tree saps in northern and eastern parts of Europe

    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.

  4. A cross-site comparison of factors influencing soil nitrification rates in northeastern USA forested watersheds

    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.

  5. Mineralization and nitrification patterns at eight northeastern USA forested research sites

    Ross, D.S.; Lawrence, G.B.; Fredriksen, G.

    2004-01-01

    Nitrogen transformation rates in eight northeastern US research sites were measured in soil samples taken in the early season of 2000 and the late season of 2001. Net mineralization and nitrification rates were determined on Oa or A horizon samples by two different sampling methods - intact cores and repeated measurements on composite samples taken from around the cores. Net rates in the composite samples (n=30) showed three different temporal patterns: high net nitrification with minimal NH4+ accumulation, high net nitrification and high NH4+ accumulation, and minimal net nitrification and moderate NH4+ accumulation. The 4-week net rates in intact cores were about half that of the rates from the composite samples but were well related (R2 > 0.70). Composite samples from sites that exhibited high net nitrification were incubated with acetylene and net nitrification was completely stopped, suggesting an autotrophic pathway. Gross mineralization and nitrification (2000 only) rates were estimated using the isotope dilution technique. Gross rates of nitrification and consumption in intact cores were relatively low. Gross rates of mineralization and net rates of nitrification were both related to the soil C/N ratio, with higher rates generally occurring in sites containing Acer saccharum as a dominant or co-dominant species. The comparison of methods suggests that all provide a similar hierarchy of potential rates but that the degree of net nitrification is strongly influenced by the degree of sample disturbance. Differences between sites appear to be related to an interaction of soil (C/N) and vegetation (A. saccharum contribution) characteristics. ?? 2003 Elsevier B.V. All rights reserved.

  6. Aspectos experimentales de la determinacion de curvas esfuerzo-deformacion a alta temperatura y en atmosfera controlada: Refractarios Al2O3-MgO-C

    Cavalieri, A. L.

    2011-06-01

    Full Text Available A methodology for the mechanical evaluation of refractory materials at high temperatures and controlled atmosphere, designed and implemented in the Structural Materials Laboratory of Ceramics Division of INTEMA, is described. The methodology includes the measurement of the specimen deformation by contact extensometry in compression tests to obtain stress-strain curves and the use of a gaseous flow as a system to control atmosphere. The determination of stress-strain curves of Al2O3-MgO-C commercial refractories used in steelmaking ladles at room temperature and 1260°C in different atmospheres is presented as an example of application of this methodology.Se presenta una metodología diseñada e implementada en el Laboratorio de Materiales Estructurales de la División Cerámicos del INTEMA para la evaluación del comportamiento mecánico de materiales refractarios a altas temperaturas y en atmósfera controlada. La metodología comprende la determinación de la deformación por extensometría de contacto en ensayos en compresión con el fin de obtener curvas esfuerzo-deformación y el uso de un sistema de control de atmósfera por desplazamiento a través del pasaje de una corriente gaseosa. La determinación de curvas esfuerzo-deformación de ladrillos refractarios comerciales Al2O3-MgO-C utilizados en cucharas de acería a temperatura ambiente y a 1260 °C en diferentes atmósferas se presenta como ejemplo de aplicación de esta metodología.

  7. Investigation of free amino acid, total phenolics, antioxidant activity and purine alkaloids to assess the health properties of non-Camellia tea.

    Bi, Wu; He, Chunnian; Ma, Yunyun; Shen, Jie; Zhang, Linghua Harris; Peng, Yong; Xiao, Peigen

    2016-03-01

    To find novel functional beverages from folk teas, 33 species of frequently used non-Camellia tea (plants other than Camellia) were collected and compared with Camellia tea (green tea, pu-erh tea and black tea) for the first time. Data are reported here on the quantities of 20 free amino acids (FAAs) and three purine alkaloids (measured by UHPLC), total polyphenols (measured by Folin-Ciocalteu assay), and antioxidant activity (DPPH). The total amounts of FAAs in non-Camellia tea (0.62-18.99 mg/g) are generally less than that of Camellia tea (16.55-24.99 mg/g). However, for certain FAAs, the quantities were much higher in some non-Camellia teas, such as γ-aminobutyric acid in teas from Ampelopsis grossedentata, Isodon serra and Hibiscus sabdariffa. Interestingly, theanine was detected in tea from Potentilla fruticosa (1.16±0.81 mg/g). Furthermore, the content of polyphenols in teas from A. grossedentata, Acer tataricum subsp. ginnala are significantly higher than those from Camellia tea; teas from I. serra, Pistacia chinensis and A. tataricum subsp. ginnala have remarkable antioxidant activities similar to the activities from green tea (44.23 μg/mL). Purine alkaloids (caffeine, theobromine and theophylline) were not detected in non-Camellia teas. The investigation suggest some non-Camellia teas may be great functional natural products with potential for prevention of chronic diseases and aging, by providing with abundant polyphenols, antioxidants and specific FAAs. PMID:27006902

  8. SPRING FLORA OF CEMETERIES OF ODESSA

    SPRING FLORA OF CEMETERIES OF ODESSA

    2014-04-01

    Full Text Available The spring flora was analyzed on six cemeteries in Odessa, such cemeteries as Vtoroe xristianskoe, Troickoe, Tairovskoe, Trete evrejskoe, Oficerskoe (Dmitrievskое and Severnoe. There were found and identified 235 species of plants, which belong to 186 genera and 67 families. There was taken a taxonomic analysis of flora of the cemeteries also of spreding of plants by ekobiomorphs, the analysis of hronotyp and origin. The proportion of the flora on the cemeteries is 1:2,8:3,5. The dominant family of the flora of Odessa’s cemeteries is Asteraceae. There are other leading families such as Rosaceae, Fabaceae, Poaceae, Brassicaceae, Lamiaceae. Herbs and trees are dominant among the life forms. Mesophytes and kseromezophytes are in the majority among hihromorphs. Heliophytes are on the first place by adapting to the light. Our results showed that the adventitious plants occupy up to 44% of all amount of plants at the cemeteries in Odessa. Kenophytes is a dominant group among them. Floragenetics analysis revealed the dominance of the plants from Asia. There have been allocated plants that were met at all six cemeteries independently of the location religious and age characteristics of the cemetery. "Core" of the flora of Odessa’s cemetery have made weed Acer negundo L., Ballota nigra L. and decorative Hedera helix L., Centaurea dealbata Willd., Buxus sempervirens L., Convallaria majalis L., Sedum kamtschaticum Fisch., Thuja occidentalis L., Hemerocalis fulva (L. L. There were found 4 species of plants that belong to the rare and endangered plants of Odessa’s region: Convallaria majalis L., Hyacinthella leucophaea (K. Koch Schur, Clematis integrifolia L., Paeonia tenuifolia L. Moreover Convallaria majalis L. grows on all six investigated cemeteries. Also two species: Hyacinthella leucophaea (K. Koch Schur and Clematis

  9. Effect of controlled inoculation with specific mycorrhizal fungi from the urban environment on growth and physiology of containerized shade tree species growing under different water regimes.

    Fini, Alessio; Frangi, Piero; Amoroso, Gabriele; Piatti, Riccardo; Faoro, Marco; Bellasio, Chandra; Ferrini, Francesco

    2011-11-01

    The aim of this work was to evaluate the effects of selected mycorrhiza obtained in the urban environment on growth, leaf gas exchange, and drought tolerance of containerized plants growing in the nursery. Two-year-old uniform Acer campestre L., Tilia cordata Mill., and Quercus robur L. were inoculated with a mixture of infected roots and mycelium of selected arbuscular (maple, linden) and/or ectomycorrhiza (linden, oak) fungi and grown in well-watered or water shortage conditions. Plant biomass and leaf area were measured 1 and 2 years after inoculation. Leaf gas exchange, chlorophyll fluorescence, and water relations were measured during the first and second growing seasons after inoculation. Our data suggest that the mycelium-based inoculum used in this experiment was able to colonize the roots of the tree species growing in the nursery. Plant biomass was affected by water shortage, but not by inoculation. Leaf area was affected by water regime and, in oak and linden, by inoculation. Leaf gas exchange was affected by inoculation and water stress. V(cmax) and J(max) were increased by inoculation and decreased by water shortage in all species. F(v)/F(m) was also generally higher in inoculated plants than in control. Changes in PSII photochemistry and photosynthesis may be related to the capacity of inoculated plants to maintain less negative leaf water potential under drought conditions. The overall data suggest that inoculated plants were better able to maintain physiological activity during water stress in comparison to non-inoculated plants. PMID:21472449

  10. Quantifying Age-Related Hydraulic and Biochemical Constraints on Tree Photosynthesis in the Southern Appalachian Mountains

    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

  11. Changes in radiocesium contamination from Fukushima in foliar parts of 10 common tree species in Japan between 2011 and 2013

    Yearly changes in radiocesium (137Cs) contamination, primarily due to the Fukushima accident of March 2011, were observed in the foliar parts of 10 common woody species in Japan (Chamaecyparis obtusa, Cedrus deodara, Pinus densiflora, Cryptomeria japonica, Phyllostachys pubescens, Cinnamomum camphora, Metasequoia glyptostroboides, Prunus × yedoensis, Acer buergerianum, and Aesculus hippocastanum). The samples were obtained from Abiko (approximately 200 km SSW of the Fukushima Dai-ichi Nuclear Power Plant) during each growing season between 2011 and 2013, and the foliar parts were examined based on their year of expansion and location in each trees. The radiocesium concentrations generally decreased with time; however, the concentrations and rates of decrease varied among species, age of foliar parts, and locations. The radiocesium concentrations in the 2012 current-year foliar parts were 29%–220% of those from 2011, while those from 2013 fell to between 14% and 42% of the 2011 values. The net decontamination in the foliage was higher in evergreen species than in deciduous species. The radiocesium concentrations in the upper foliar parts were higher than those in the lower parts particularly in C. japonica. In addition, the radiocesium concentrations were higher in the current-year foliar parts than in the 1-year-old foliar parts, particularly in 2013. Thus, the influence of the direct deposition of the fallout was reduced with time, and the translocation ability of radiocesium from old to new tissues became more influential. Similar to the behavior of potassium in trees, Cs redistribution probably occurred primarily due to internal nutrient translocation mechanisms. - Highlights: • 137Cs concentrations of foliar parts expanded in 2013 was 14–42% of those in 2011. • The rates of decrease varied with the species, sampling part, and position. • Newly expanded foliar parts contain higher 137Cs concentrations than older parts. • 137Cs translocation

  12. Tree Distributions, Subsurface Characteristics and Nitrogen Cycling

    Brunner, L.; Wallace, M. C.; Brush, G.

    2014-12-01

    This study examines the connection between vegetation and geologic, soil and hydrologic subsurface characteristics of a natural deciduous forest in Oregon Ridge Park, located in the Piedmont physiographic province in Maryland, USA. A preliminary study showed the relationship between nitrogen cycling and four different species occurring on a coarse grained schist and a fine grained schist. Mineralization values for Liriodendon tulipifera were positive on the coarser grained substrate and negative on the fine grained substrate. Nitrification values were positive on both substrates. Mineralization and nitrification values were both positive for Quercus prinus on both the coarse and fine substrates. Mineralization values for Acer rubrum were negative on the coarse substrate and positive on the finer substrate, while mineralization for Quercus rubra was negative on the coarse substrate and positive on the fine schist. Nitrification was positive for Q. rubra on the coarse schist and both positive and negative on the fine schist. Resistivity analyses were performed in collaboration with the Wyoming Center for Environmental Hydrology and Geophysics (WyCEHG) along two perpendicular transects at the study site. This analysis provides indirect information on subsurface conductivity, with low resistivity being interpreted as subsurface water or clay. One transect crossed a valley with a first-order stream in the center, while the second transect was taken along the break and slope of the hillslope. All trees were identified and diameter at breast height (DBH) measured in sixty-three randomly located plots along both transects. A principle components analysis of all tree data showed four associations of species. The plots were labelled as to association. The position of the associations along the transects show a relationship between wet, dry and mesic associations with differences in transect resistivity.

  13. Understanding the effects of intermediate disturbances on evapotranspiration in the upper Midwest

    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.

  14. Differences in impacts of Hurricane Sandy on freshwater swamps on the Delmarva Peninsula, Mid−Atlantic Coast, USA

    Middleton, Beth A.

    2016-01-01

    Hurricane wind and surge may have different influences on the subsequent composition of forests. During Hurricane Sandy, while damaging winds were highest near landfall in New Jersey, inundation occurred along the entire eastern seaboard from Georgia to Maine. In this study, a comparison of damage from salinity intrusion vs. wind/surge was recorded in swamps of the Delmarva Peninsula along the Pocomoke (MD) and Nanticoke (DE) Rivers, south of the most intense wind damage. Hickory Point Cypress Swamp (Hickory) was closest to the Chesapeake Bay and may have been subjected to a salinity surge as evidenced by elevated salinity levels at a gage upstream of this swamp (storm salinity = 13.1 ppt at Nassawango Creek, Snow Hill, Maryland). After Hurricane Sandy, 8% of the standing trees died at Hickory including Acer rubrum, Amelanchier laevis, Ilex spp., and Taxodium distichum. In Plot 2 of Hickory, 25% of the standing trees were dead, and soil salinity levels were the highest recorded in the study. The most important variables related to structural tree damage were soil salinity and proximity to the Atlantic coast as based on Stepwise Regression and NMDS procedures. Wind damage was mostly restricted to broken branches although tipped−up trees were found at Hickory, Whiton and Porter (species: Liquidamabar styraciflua, Pinus taeda, Populus deltoides, Quercus pagoda and Ilex spp.). These trees fell mostly in an east or east−southeast direction (88o−107o) in keeping with the wind direction of Hurricane Sandy on the Delmarva Peninsula. Coastal restoration and management can be informed by the specific differences in hurricane damage to vegetation by salt versus wind.

  15. A Grassroots Remote Sensing Toolkit Using Live Coding, Smartphones, Kites and Lightweight Drones

    Anderson, K.; Griffiths, D.; DeBell, L.; Hancock, S.; Duffy, J. P.; Shutler, J. D.; Reinhardt, W. J.; Griffiths, A.

    2016-01-01

    This manuscript describes the development of an android-based smartphone application for capturing aerial photographs and spatial metadata automatically, for use in grassroots mapping applications. The aim of the project was to exploit the plethora of on-board sensors within modern smartphones (accelerometer, GPS, compass, camera) to generate ready-to-use spatial data from lightweight aerial platforms such as drones or kites. A visual coding ‘scheme blocks’ framework was used to build the application (‘app’), so that users could customise their own data capture tools in the field. The paper reports on the coding framework, then shows the results of test flights from kites and lightweight drones and finally shows how open-source geospatial toolkits were used to generate geographical information system (GIS)-ready GeoTIFF images from the metadata stored by the app. Two Android smartphones were used in testing–a high specification OnePlus One handset and a lower cost Acer Liquid Z3 handset, to test the operational limits of the app on phones with different sensor sets. We demonstrate that best results were obtained when the phone was attached to a stable single line kite or to a gliding drone. Results show that engine or motor vibrations from powered aircraft required dampening to ensure capture of high quality images. We demonstrate how the products generated from the open-source processing workflow are easily used in GIS. The app can be downloaded freely from the Google store by searching for ‘UAV toolkit’ (UAV toolkit 2016), and used wherever an Android smartphone and aerial platform are available to deliver rapid spatial data (e.g. in supporting decision-making in humanitarian disaster-relief zones, in teaching or for grassroots remote sensing and democratic mapping). PMID:27144310

  16. Boron toxicity characteristics of four northern California endemic tree species

    Glaubig, B.A.; Bingham, F.T.

    A greenhouse study was undertaken to determine the characteristics of soil B toxicity for four tree species endemic to The Geysers area in northern California: digger pine (Pinus sabiniana Dougl. ex D. Don), California laurel (or, California bay) (Umbellularia californica (Hoo. and Arn. Nutt.)), madrone (Arbutus menziesii Pursh), and bigleaf maple (Acer macrophyllum Pursh). Significant exponential relationships were found between soil B concentration and relative growth, and between tissue B concentration and relative growth for the four species. Significant linear relationships were found between both soil and tissue B concentration and foliar damage for the four species. Foliar damages over 25% of the leaf or needle area on digger pine, California laurel, madrone, and bigleaf maple, respectively, occurred at saturated soil extract concentrations (mmol B/L) of 1.2, 0.4, 0.5, and 0.08. Twenty-five percent foliar damage was associated with leaf or needle tissue concentrations (mmol B/kg) of 115, 100, 50, and 30 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Growth decrements of 25% occurred at saturated soil extract concentrations (mmol B/L) of 1.6, 0.3, 0.2, 0.5 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Twenty-five percent growth decrements were associated with leaf or needle tissue concentrations (mmol B/kg) of 140, 100, 20, and 7 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. By comparison with two agronomic crops - cotton (Gossypium hirsutum L.) and cowpea (Vigna unguiculata L.) - the four tree species were placed into one of six B tolerance classes.

  17. A Grassroots Remote Sensing Toolkit Using Live Coding, Smartphones, Kites and Lightweight Drones.

    Anderson, K; Griffiths, D; DeBell, L; Hancock, S; Duffy, J P; Shutler, J D; Reinhardt, W J; Griffiths, A

    2016-01-01

    This manuscript describes the development of an android-based smartphone application for capturing aerial photographs and spatial metadata automatically, for use in grassroots mapping applications. The aim of the project was to exploit the plethora of on-board sensors within modern smartphones (accelerometer, GPS, compass, camera) to generate ready-to-use spatial data from lightweight aerial platforms such as drones or kites. A visual coding 'scheme blocks' framework was used to build the application ('app'), so that users could customise their own data capture tools in the field. The paper reports on the coding framework, then shows the results of test flights from kites and lightweight drones and finally shows how open-source geospatial toolkits were used to generate geographical information system (GIS)-ready GeoTIFF images from the metadata stored by the app. Two Android smartphones were used in testing-a high specification OnePlus One handset and a lower cost Acer Liquid Z3 handset, to test the operational limits of the app on phones with different sensor sets. We demonstrate that best results were obtained when the phone was attached to a stable single line kite or to a gliding drone. Results show that engine or motor vibrations from powered aircraft required dampening to ensure capture of high quality images. We demonstrate how the products generated from the open-source processing workflow are easily used in GIS. The app can be downloaded freely from the Google store by searching for 'UAV toolkit' (UAV toolkit 2016), and used wherever an Android smartphone and aerial platform are available to deliver rapid spatial data (e.g. in supporting decision-making in humanitarian disaster-relief zones, in teaching or for grassroots remote sensing and democratic mapping). PMID:27144310

  18. Ground cover and tree growth on calcareous minesoils: Greater influence of soil surface than nitrogen rate or seed mix

    Growth of ground cover and trees was evaluated for five growing seasons on calcareous coal minesoil surfaces (standard graded topsoil, graded and ripped topsoil, graded gray cast overburden) in southeastern Ohio. Soil surface plots were seeded in September 1987 with either a standard herbaceous seed mix [orchardgrass (Dactylis glomerata L.), timothy (Phleum pratense L.), perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), Ranger alfalfa (Medicago sativa L.), Mammoth red clover (Trifolium pratense L.), Empire birdsfoot trefoil (Lotus corniculatus L.), and wheat (Triticum aestivum L.)], or a modified mix using no alfalfa and half the rate of orchardgrass. Nitrogen (45, 90, or 135 kg ha/N) was applied as ammonium nitrate in September 1987 and April 1989. White ash (Fraxinus americana L.), silver maple (Acer saccharinum L.), northern red oak (Quercus rubra L.), and eastern white pine (Pinus strobus L.) were planted in spring 1989 into 0.8 m-wide strips sprayed with glyphosate herbicide at 2.24 kg/ha in October 1988. Total cover and total biomass were highest in July 1989, following the last application of nitrogen fertilizer in April 1989. Total cover ranged from 44% to 56%, and total biomass ranged from 102 to 162 g/0.5 m2 from 1990 to 1993. Total cover and total biomass were lower at the lowest nitrogen rate in 1989 only. Type of herbaceous seed mix did not affect growth of ground cover or trees. Overall tree survival was 82.0% the first year but declined to 40.6% after 5 yr. Survival varied significantly among all tree species (3.5% for pine, 22.2% for oak, 38.5% for maple, 98.1% for ash)

  19. Assessment of fly ash-aided phytostabilisation of highly contaminated soils after an 8-year field trial

    Aided phytostabilisation is a cost-efficient technique to manage metal-contaminated areas, particularly in the presence of extensive pollution. Plant establishment and survival in highly metal-contaminated soils are crucial for phytostabilisation success, as metal toxicity for plants is widely reported. A relevant phytostabilisation solution must limit metal transfer through the food chain. Therefore, this study aimed at evaluating the long-term efficiency of aided phytostabilisation on former agricultural soils highly contaminated by cadmium, lead, and zinc. The influence of afforestation and fly ash amendments on reducing metal phytoavailability was investigated as were their effects on plant development. Before being planted with a tree mix, the site was divided into three plots: a reference plot with no amendment, a plot amended with silico-aluminous fly ash and one with sulfo-calcic fly ash. Unlike Salix alba and Quercus robur, Alnus glutinosa, Acer pseudoplatanus and Robinia pseudoacacia grew well on the site and accumulated, overall, quite low concentrations of metals in their leaves and young twigs. This suggests that these three species have an excluder phenotype for Cd, Zn and Pb. After 8 years, metal availability to A. glutinosa, A. pseudoplatanus and R. pseudoacacia, and translocation to their above-ground parts, strongly decreased in fly ash-amended soils. Such decreases fit well together with the depletion of CaCl2-extractable metals in amended soils. Although both fly ashes were effective to decrease Cd, Pb and Zn concentrations in above-ground parts of trees, the sulfo-calcic ash was more efficient.

  20. Early spring leaf out enhances growth and survival of saplings in a temperate deciduous forest.

    Augspurger, Carol K

    2008-05-01

    Saplings of many canopy tree species in winter deciduous forests receive the major portion of their light budget for their growing season prior to canopy closure in the spring. This period of high light may be critical for achieving a positive carbon (C) gain, thus contributing strongly to their growth and survival. This study of saplings of Aesculus glabra and Acer saccharum in Trelease Woods, Illinois, USA, tested this hypothesis experimentally by placing tents of shade cloth over saplings during their spring period of high light prior to canopy closure in three consecutive years. Leaf senescence began 16 days (year 0) and 60 days (year 1) earlier for shaded A. glabra saplings than control saplings. No change in senescence occurred for A. saccharum. The annual absolute growth in stem diameter of both species was negligible or negative for shaded saplings, but positive for control saplings. Only 7% of the shaded A. glabra saplings were alive after 2 years, while all control saplings survived for 3 years; only 20% of the shaded A. saccharum saplings survived for 3 years, while 73% of control saplings were alive after the same period. Early spring leaf out is a critical mechanism that allows the long-term persistence of saplings of these species in this winter deciduous forest. Studies and models of C gain, growth, and survival of saplings in deciduous forests may need to take into account their spring phenology because saplings of many species are actually "sun" individuals in the spring prior to their longer period in the summer shade. PMID:18347817

  1. A six-year study of sapling and large-tree growth and mortality responses to natural and induced variability in precipitation and throughfall.

    Hanson, P J; Todd, D E; Amthor, J S

    2001-04-01

    Global climatic change may cause changes in regional precipitation that have important implications for forest growth in the southern United States. In 1993, a stand-level experiment was initiated on Walker Branch Watershed, Tennessee, to study the sensitivity of forest saplings and large trees to changes in soil water content. Soil water content was manipulated by gravity-driven transfer of precipitation throughfall from a dry treatment plot (-33%) to a wet treatment plot (+33%). A control plot was included. Each plot was 6400 m2. Measurements of stem diameter and observations of mortality were made on large trees and saplings of Acer rubrum L., Cornus florida L., Liriodendron tulipifera L., Nyssa sylvatica Marsh, Quercus alba L. and Quercus prinus L. every 2 weeks during six growing seasons. Saplings of C. florida and A. rubrum grew faster and mortality was less on the wet plot compared with the dry and control plots, through 6 years of soil water manipulation. Conversely, diameter growth of large trees was unaffected by the treatments. However, tree diameter growth averaged across treatments was affected by year-to- year changes in soil water status. Growth in wet years was as much as 2-3 times greater than in dry years. Relationships between tree growth, phenology and soil water potential were consistent among species and quantitative expressions were developed for application in models. These field growth data indicate that differences in seasonal patterns of rainfall within and between years have greater impacts on growth than percentage changes in rainfall applied to all rainfall events. PMID:11282574

  2. Quality assessment of urban trees using growth visual and chlorophyll fluorescence indicators

    Uhrin Peter

    2016-06-01

    Full Text Available Urbanised landscape represents composed structures of technical and biotic elements where social and economy activities create living space for human society but with strongly changed environment. To dominant characters belong climate changes with increased air temperature, drought and emission load, which has developed wide spectrum of stress factors influencing the urban vegetation. For the assessment of plant growth and adaptation response, we have used Sycamore maple (Acer pseudoplatanus L. as study model woody plant. In the framework of visual characters, we assessed the following indicators: (a assimilation organs (leaf necrosis; (b crown quality (degree of foliage and degree of dead tree crown; (c trunk and branch quality (mechanical damage, incidence of wood destroying fungus and trunk cavities and callus healing of trunk wounds. Each indicator was assessed in five-point scale, and in the end, the common index of quality was calculated. The quality index achieved 9.33 points in the first and 10.33 in the second evaluation periods in the Nitra city and 2.66 at the both assessed periods in the comparable rural park. In the group of physiological indicators, chlorophyll a fluorescence marker and its Fv/Fm parameter were used. Within three repeating assessment during growing season (June, August and September, the average values reached Fv/Fm = 0.814 in the city and Fv/Fm = 0.829 in rural park. The results confirmed statistical significances between loaded city conditions and relatively clean rural locality. Used markers have shown as appropriate tools for growth response measurements of street trees in a changed urban environment.

  3. Seasonal and interannual variability of canopy transpiration of a hedgerow in southern England.

    Herbst, Mathias; Roberts, John M; Rosier, Paul T W; Gowing, David J

    2007-03-01

    Transpiration from a hawthorn (Crataegus monogyna L.) dominated hedgerow in southern England was measured continuously over two growing seasons by the sap flow technique. Accompanying measurements of structural parameters, microclimate and leaf stomatal and boundary layer conductances were used to establish the driving factors of hedgerow transpiration. Observed transpiration rates, reaching peak values of around 8 mm day(-1) and a seasonal mean of about 3.5 mm day(-1), were higher than those reported for most other temperate deciduous woodlands, except short-rotation coppice and wet woodlands. The high rates were caused by the structural and physiological characteristics of hawthorn leaves, which exhibited much higher stomatal and boundary-layer conductances than those of the second-most abundant woody species in the hedgerow, field maple (Acer campestre L.). Only in the hot summer of 2003 did stomatal conductance, and thus transpiration, decrease substantially. The hedgerow canopy was always closely coupled to the atmosphere. Hedgerow transpiration equaled potential evaporation (calculated by the Priestley-Taylor formula) in 2003 and exceeded it in 2004, which meant that a substantial fraction of the energy (21% in 2003 and more than 37% in 2004) came from advection. Hedgerow canopy conductance (g(c)), as inferred from the sap flow data by inverting the Penman-Monteith equation, responded to solar radiation (R(G)) and vapor pressure deficit (D). Although the response to R(G) showed no systematic temporal variation, the response to D, described as g(c)(D) = g(cref) - mln(D), changed seasonally. The reference g(c) depended on leaf area index and the ratio of -m/g(cref) on long-term mean daytime D. A model is proposed based on these observations that predicts canopy conductance for the hawthorn hedge from standard weather data. PMID:17241974

  4. Vegetation classification in southern pine mixed hardwood forests using airborne scanning laser point data.

    McGaughey, Robert J. [USDA Forest Service, Pacific Northwest Research Station; Reutebuch, Stephen E. [USDA Forest Service, Pacific Northwest Research Station

    2012-09-01

    Forests of the southeastern United States are dominated by a relatively small number of conifer species. However, many of these forests also have a hardwood component composed of a wide variety of species that are found in all canopy positions. The presence or absence of hardwood species and their position in the canopy often dictates management activities such as thinning or prescribed burning. In addition, the characteristics of the under- and mid-story layers, often dominated by hardwood species, are key factors when assessing suitable habitat for threatened and endangered species such as the Red Cockaded Woodpecker (Picoides borealis) (RCW), making information describing the hardwood component important to forest managers. General classification of cover types using LIDAR data has been reported (Song et al. 2002, Brennan and Webster 2006) but most efforts focusing on the identification of individual species or species groups rely on some type of imagery to provide more complete spectral information for the study area. Brandtberg (2007) found that use of intensity data significantly improved LIDAR detection and classification of three leaf-off deciduous eastern species: oaks (Quercus spp.), red maple (Acer rubrum L.), and yellow poplar (Liriodendron tulipifera L.). Our primary objective was to determine the proportion of hardwood species present in the canopy using only the LIDAR point data and derived products. However, the presence of several hardwood species that retain their foliage through the winter months complicated our analyses. We present two classification approaches. The first identifies areas containing hardwood and softwood (conifer) species (H/S) and the second identifies vegetation with foliage absent or present (FA/FP) at the time of the LIDAR data acquisition. The classification results were used to develop predictor variables for forest inventory models. The ability to incorporate the proportion of hardwood and softwood was important to the

  5. Ionic liquids influence on the surface properties of electron beam irradiated wood

    Croitoru, Catalin [“Transilvania” University of Brasov, Product Design and Environment Department, 29 Eroilor Str., 500036, Brasov (Romania); Patachia, Silvia, E-mail: st.patachia@unitbv.ro [“Transilvania” University of Brasov, Product Design and Environment Department, 29 Eroilor Str., 500036, Brasov (Romania); Doroftei, Florica; Parparita, Elena; Vasile, Cornelia [“Petru Poni” Institute of Macromolecular Chemistry, Physical Chemistry of Polymers Department, 41A Gr. Ghica Voda Alley, Iasi (Romania)

    2014-09-30

    Highlights: • Wood veneers impregnated with three imidazolium-based ionic liquids and irradiated with electron beam were studied by FTIR-ATR, SEM/EDX, AFM, contact angle and image analysis. • ILs preserve the surface properties of the wood (surface energy, roughness, color) upon irradiation, in comparison with the reference wood, but the surface composition is changed by treatment with IL-s, mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. • Under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface. - Abstract: In this paper, the influence of three imidazolium-based ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-hexyl-3-methylimidazolium chloride) on the structure and surface properties of sycamore maple (Acer pseudoplatanus) veneers submitted to electron beam irradiation with a dose of 50 kGy has been studied by using Fourier transform infrared spectroscopy, as well as image, scanning electron microscopy/SEM/EDX, atomic force microscopy and contact angle analysis. The experimental results have proven that the studied ionic liquids determine a better preservation of the structural features of wood (cellulose crystallinity index and lignin concentration on the surface) as well as some of surface properties such as surface energy, roughness, color upon irradiation with electron beam, in comparison with the reference wood, but surface composition is changed by treatment with imidazolium-based ionic liquids mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. Also, under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface.

  6. Assessment of fly ash-aided phytostabilisation of highly contaminated soils after an 8-year field trial

    Pourrut, Bertrand [Universite Lille Nord de France, Lille (France); Groupe ISA, Equipe Sols et Environnement, Laboratoire Genie Civil et geoEnvironnement (LGCgE) Lille Nord de France EA 4515, 48 boulevard Vauban, 59046 Lille Cedex (France); Lopareva-Pohu, Alena [Universite Lille Nord de France, Lille (France); Groupe ISA, Equipe Sols et Environnement, Laboratoire Genie Civil et geoEnvironnement (LGCgE) Lille Nord de France EA 4515, 48 boulevard Vauban, 59046 Lille Cedex (France); Universite du Littoral-Cote d' Opale, Unite de Chimie Environnementale et Interaction sur le Vivant (UCEIV), EA 4492, Maison de la Recherche en Environnement Industriel de Dunkerque 2, avenue Maurice Schumann, 59140 Dunkerque (France); Pruvot, Christelle [Universite Lille Nord de France, Lille (France); Groupe ISA, Equipe Sols et Environnement, Laboratoire Genie Civil et geoEnvironnement (LGCgE) Lille Nord de France EA 4515, 48 boulevard Vauban, 59046 Lille Cedex (France); Garcon, Guillaume; Verdin, Anthony [Universite Lille Nord de France, Lille (France); Universite du Littoral-Cote d' Opale, Unite de Chimie Environnementale et Interaction sur le Vivant (UCEIV), EA 4492, Maison de la Recherche en Environnement Industriel de Dunkerque 2, avenue Maurice Schumann, 59140 Dunkerque (France); Waterlot, Christophe; Bidar, Geraldine [Universite Lille Nord de France, Lille (France); Groupe ISA, Equipe Sols et Environnement, Laboratoire Genie Civil et geoEnvironnement (LGCgE) Lille Nord de France EA 4515, 48 boulevard Vauban, 59046 Lille Cedex (France); Shirali, Pirouz [Universite Lille Nord de France, Lille (France); Universite du Littoral-Cote d' Opale, Unite de Chimie Environnementale et Interaction sur le Vivant (UCEIV), EA 4492, Maison de la Recherche en Environnement Industriel de Dunkerque 2, avenue Maurice Schumann, 59140 Dunkerque (France); and others

    2011-10-01

    Aided phytostabilisation is a cost-efficient technique to manage metal-contaminated areas, particularly in the presence of extensive pollution. Plant establishment and survival in highly metal-contaminated soils are crucial for phytostabilisation success, as metal toxicity for plants is widely reported. A relevant phytostabilisation solution must limit metal transfer through the food chain. Therefore, this study aimed at evaluating the long-term efficiency of aided phytostabilisation on former agricultural soils highly contaminated by cadmium, lead, and zinc. The influence of afforestation and fly ash amendments on reducing metal phytoavailability was investigated as were their effects on plant development. Before being planted with a tree mix, the site was divided into three plots: a reference plot with no amendment, a plot amended with silico-aluminous fly ash and one with sulfo-calcic fly ash. Unlike Salix alba and Quercus robur, Alnus glutinosa, Acer pseudoplatanus and Robinia pseudoacacia grew well on the site and accumulated, overall, quite low concentrations of metals in their leaves and young twigs. This suggests that these three species have an excluder phenotype for Cd, Zn and Pb. After 8 years, metal availability to A. glutinosa, A. pseudoplatanus and R. pseudoacacia, and translocation to their above-ground parts, strongly decreased in fly ash-amended soils. Such decreases fit well together with the depletion of CaCl{sub 2}-extractable metals in amended soils. Although both fly ashes were effective to decrease Cd, Pb and Zn concentrations in above-ground parts of trees, the sulfo-calcic ash was more efficient.

  7. Identification, pathogenicity and abundance of Paracremonium pembeum sp. nov. and Graphium euwallaceae sp. nov.--two newly discovered mycangial associates of the polyphagous shot hole borer (Euwallacea sp.) in California.

    Lynch, Shannon Colleen; Twizeyimana, Mathias; Mayorquin, Joey Sal; Wang, Danny Ho; Na, Francis; Kayim, Mukaddes; Kasson, Matthew T; Thu, Pham Quang; Bateman, Craig; Rugman-Jones, Paul; Hulcr, Jiri; Stouthamer, Richard; Eskalen, Akif

    2016-01-01

    Fusarium euwallaceae is a well-characterized fungal symbiont of the exotic ambrosia beetle Euwallacea sp. (polyphagous shot hole borer [PSHB]), together inciting Fusarium dieback on many host plants in Israel and California. Recent discoveries of additional fungal symbionts within ambrosia beetle mycangia suggest these fungi occur as communities. Colony-forming units of Graphium euwallaceae sp. nov. and Paracremonium pembeum sp. nov., two novel fungal associates of PSHB from California, grew from 36 macerated female heads and 36 gallery walls collected from Platanus racemosa, Acer negundo, Persea americana and Ricinus communis. Fungi were identified based on micromorphology and phylogenetic analyses of the combined internal transcribed spacer region (nuc rDNA ITS1-5.8S-ITS2 [ITS barcode]), elongation factor (EF 1-α), small subunit (18S rDNA) sequences for Graphium spp., ITS, EF 1-α, calmodulin (cmdA), large subunit of the ATP citrate lyase (acl1), β-tubulin (tub2), RNA polymerase II second largest subunit (rpb2) and large subunit (28S rDNA) sequences for Paracremonium spp. Other Graphium spp. recovered from PSHB in Vietnam, Euwallacea fornicatus in Thailand, E. validus in Pennsylvania and Paracremonium sp. recovered from PSHB in Vietnam were identified. F. euwallaceae was recovered from mycangia at higher frequencies and abundances in all hosts except R. communis, in which those of F. euwallaceae and P. pembeum were equal. P. pembeum was relatively more abundant within gallery walls of A. negundo and R. communis. In all hosts combined F. euwallaceae was relatively more abundant within PSHB heads than gallery walls. All three fungi grew at different rates and colonized inoculated excised stems of P. americana and A. negundo. P. pembeum produced longer lesions than F. euwallaceae and G. euwallaceae on inoculated avocado shoots. Results indicate PSHB is associated with a dynamic assemblage of mycangial fungal associates that pose additional risk to native and

  8. Separating temperature from other factors in phenological measurements

    Schwartz, Mark D.; Hanes, Jonathan M.; Liang, Liang

    2014-09-01

    Phenological observations offer a simple and effective way to measure climate change effects on the biosphere. While some species in northern mixed forests show a highly sensitive site preference to microenvironmental differences (i.e., the species is present in certain areas and absent in others), others with a more plastic environmental response (e.g., Acer saccharum, sugar maple) allow provisional separation of the universal "background" phenological variation caused by in situ (possibly biological/genetic) variation from the microclimatic gradients in air temperature. Moran's I tests for spatial autocorrelation among the phenological data showed significant ( α ≤ 0.05) clustering across the study area, but random patterns within the microclimates themselves, with isolated exceptions. In other words, the presence of microclimates throughout the study area generally results in spatial autocorrelation because they impact the overall phenological development of sugar maple trees. However, within each microclimate (where temperature conditions are relatively uniform) there is little or no spatial autocorrelation because phenological differences are due largely to randomly distributed in situ factors. The phenological responses from 2008 and 2009 for two sugar maple phenological stages showed the relationship between air temperature degree-hour departure and phenological change ranged from 0.5 to 1.2 days earlier for each additional 100 degree-hours. Further, the standard deviations of phenological event dates within individual microclimates (for specific events and years) ranged from 2.6 to 3.8 days. Thus, that range of days is inferred to be the "background" phenological variation caused by factors other than air temperature variations, such as genetic differences between individuals.

  9. A Grassroots Remote Sensing Toolkit Using Live Coding, Smartphones, Kites and Lightweight Drones.

    K Anderson

    Full Text Available This manuscript describes the development of an android-based smartphone application for capturing aerial photographs and spatial metadata automatically, for use in grassroots mapping applications. The aim of the project was to exploit the plethora of on-board sensors within modern smartphones (accelerometer, GPS, compass, camera to generate ready-to-use spatial data from lightweight aerial platforms such as drones or kites. A visual coding 'scheme blocks' framework was used to build the application ('app', so that users could customise their own data capture tools in the field. The paper reports on the coding framework, then shows the results of test flights from kites and lightweight drones and finally shows how open-source geospatial toolkits were used to generate geographical information system (GIS-ready GeoTIFF images from the metadata stored by the app. Two Android smartphones were used in testing-a high specification OnePlus One handset and a lower cost Acer Liquid Z3 handset, to test the operational limits of the app on phones with different sensor sets. We demonstrate that best results were obtained when the phone was attached to a stable single line kite or to a gliding drone. Results show that engine or motor vibrations from powered aircraft required dampening to ensure capture of high quality images. We demonstrate how the products generated from the open-source processing workflow are easily used in GIS. The app can be downloaded freely from the Google store by searching for 'UAV toolkit' (UAV toolkit 2016, and used wherever an Android smartphone and aerial platform are available to deliver rapid spatial data (e.g. in supporting decision-making in humanitarian disaster-relief zones, in teaching or for grassroots remote sensing and democratic mapping.

  10. Erbium-Doped Amorphous Carbon-Based Thin Films: A Photonic Material Prepared by Low-Temperature RF-PEMOCVD

    Hui-Lin Hsu

    2014-02-01

    Full Text Available The integration of photonic materials into CMOS processing involves the use of new materials. A simple one-step metal-organic radio frequency plasma enhanced chemical vapor deposition system (RF-PEMOCVD was deployed to grow erbium-doped amorphous carbon thin films (a-C:(Er on Si substrates at low temperatures (<200 °C. A partially fluorinated metal-organic compound, tris(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5- octanedionate Erbium(+III or abbreviated Er(fod3, was incorporated in situ into a-C based host. Six-fold enhancement of Er room-temperature photoluminescence at 1.54 µm was demonstrated by deuteration of the a-C host. Furthermore, the effect of RF power and substrate temperature on the photoluminescence of a-C:D(Er films was investigated and analyzed in terms of the film structure. Photoluminescence signal increases with increasing RF power, which is the result of an increase in [O]/[Er] ratio and the respective erbium-oxygen coordination number. Moreover, photoluminescence intensity decreases with increasing substrate temperature, which is attributed to an increased desorption rate or a lower sticking coefficient of the fluorinated fragments during film growth and hence [Er] decreases. In addition, it is observed that Er concentration quenching begins at ~2.2 at% and continues to increase until 5.5 at% in the studied a-C:D(Er matrix. This technique provides the capability of doping Er in a vertically uniform profile.

  11. Photosynthetic responses of forest understory tree species to long-term exposure to elevated carbon dioxide concentration at the Duke Forest FACE experiment

    Springer, C.J. [West Virginia Univ., Morgantown, WV (United States); Thomas, R.B. [Kansas Univ., Lawrence, KS (United States). Dept. of Ecology and Evolutionary Biology

    2007-01-15

    Tree species growing within the forest understory contribute to the overall carbon balance of forest ecosystems in addition to representing many of the species that occur in the overstory of mature ecosystems. This article described a 7 year study investigating the responses of forest understory tree species to increasing concentrations of atmospheric carbon dioxide (CO{sub 2}). The study examined the photosynthetic responses of Acer rubrum L., Carya glabra Mill., Cercis Canadensis L., and Liquidambar styraciflua L. during their seventh year of exposure to elevated CO{sub 2} at the Duke Forest Free Air Carbon Enrichment (FACE) experiment to determine whether photosynthetic down-regulation had occurred, as well as to determine whether the enhancement of photosynthesis observed during the first year of exposure to elevated CO{sub 2} was sustained. The study was conducted to test a previous hypothesis that significant photosynthetic down-regulation would be observed after 7 years of exposure to elevated CO{sub 2}. Photosynthetic CO{sub 2} response and light response curves were measured, as well as chlorophyll fluorescence, chlorophyll concentration and foliar nitrogen (N). Results showed that exposure to elevated CO{sub 2} increased photosynthesis in all species measured after 7 years of treatment. The greatest photosynthetic increase was observed near saturating irradiances. In all species, elevated CO{sub 2} increased electron transport efficiency but did not significantly alter carboxylation efficiency. Quantum yield as estimated by light curves, chlorophyll concentration, and foliar N concentrations was unaffected by elevated CO{sub 2}. It was concluded that there was scant evidence of progressive N limitation of leaf-level processes in the understory species after 7 years of exposure to elevated CO{sub 2} in the experiment. 42 refs., 2 tabs., 4 figs.

  12. Comparison of heavy metal contents in their leaves by 17 road afforestation trees%17种道路绿化树木叶片重金属镉和铬含量的比较研究

    刘冰

    2014-01-01

    The urban road green trees could absorb heavy metal pollutants in the atmosphere.The heavy metals Cd and Cr contents in leaves of 17 virescence trees in Xinxiang City are analysed.The results indicate that the same road afforestation trees show different heavy metal contents in their leaves,polluted area > clear area, Autumn > Spring, Cd > Cr; simultaneously different species show quite different contents to the same heavy metal element,the content of Cd is in the order of Populus alba >Acer mono >Populus tomentosa > Ligustrum quihoui Carr > Ligustrum lucidum > Prunus ceraifera > Euonymus j aponicus > Koelreuteria paniculata > P latanus acerifolia > Ailanthus altissima > Broussonetia papyrifera > Fraxinus chinensis > Sophora j aponica > Photinia frasery > Pittosporum tobira >Yucca gloriosa >Buxus microphylla;the content of Cr is in the order of Acer mono > Populus tomentosa >Populus alba > Prunus ceraifera > Buxus microphylla > Photinia frasery > P latanus acerifolia >Sophora j aponica >Yucca gloriosa >Broussonetia papyrifera >Ligustrum quihoui Carr >Pittosporum tobira >Koelreuteria paniculata >Ligustrum lucidum >Ailanthus altissima >Fraxinus chinensis >Buxus megistophylla .The afforest trees are classified three at the basis of the content of Cd and Cr,the first category includes Populus tomentosa and Acer mono ;Prunus ceraiferai ,P latanus acerifolia ,Populus alba ,Buxus microphylla and Photinia frasery belong to the second category;the third category includes Fraxinus chinensis ,Sophora j aponica ,Broussonetia papyrifera ,Ailanthus altissima ,Koelreuteria paniculata , Pittosporum tobira ,Yucca gloriosa , Euonymus j aponicus , Ligustrum lucidum and Ligustrum quihoui Carr . Heavy metal contents in road green trees leaves show markedly difference depending on function areas,seasons,heavy metal kinds and tree species.%对新乡市17种道路绿化树木叶片重金属镉和铬的含量进行了分析,结果表明,同种道路绿化树木叶片的重金属含

  13. Stem water storage in five coexisting temperate broad-leaved tree species: significance, temporal dynamics and dependence on tree functional traits.

    Köcher, Paul; Horna, Viviana; Leuschner, Christoph

    2013-08-01

    The functional role of internal water storage is increasingly well understood in tropical trees and conifers, while temperate broad-leaved trees have only rarely been studied. We examined the magnitude and dynamics of the use of stem water reserves for transpiration in five coexisting temperate broad-leaved trees with largely different morphology and physiology (genera Fagus, Fraxinus, Tilia, Carpinus and Acer). We expected that differences in water storage patterns would mostly reflect species differences in wood anatomy (ring vs. diffuse-porous) and wood density. Sap flux density was recorded synchronously at five positions along the root-to-branch flow path of mature trees (roots, three stem positions and branches) with high temporal resolution (2 min) and related to stem radius changes recorded with electronic point dendrometers. The daily amount of stored stem water withdrawn for transpiration was estimated by comparing the integrated flow at stem base and stem top. The temporal coincidence of flows at different positions and apparent time lags were examined by cross-correlation analysis. Our results confirm that internal water stores play an important role in the four diffuse-porous species with estimated 5-12 kg day(-1) being withdrawn on average in 25-28 m tall trees representing 10-22% of daily transpiration; in contrast, only 0.5-2.0 kg day(-1) was withdrawn in ring-porous Fraxinus. Wood density had a large influence on storage; sapwood area (diffuse- vs. ring-porous) may be another influential factor but its effect was not significant. Across the five species, the length of the time lag in flow at stem top and stem base was positively related to the size of stem storage. The stem stores were mostly exhausted when the soil matrix potential dropped below -0.1 MPa and daily mean vapor pressure deficit exceeded 3-5 hPa. We conclude that stem storage is an important factor improving the water balance of diffuse-porous temperate broad-leaved trees in moist

  14. Complejidad restringida y Complejidad generalizada o las complejidades de la Complejidad

    Edgar Morin

    2007-01-01

    Full Text Available Par tien do de la ase ve ra ción acer ca de que la no ción de Com ple ji dad no se ha lla en la Fi lo - so fía re co no ci da como tal, aun que sí en to dos los pen sa do res que han de sa rro lla do una vi sion com - ple ja del mun do, se avan za ha cia la ca rac te ri za - ción del por qué la Cien cia clá si ca la ha re cha za - do des de el si glo XVII has ta el XX, si glo en que esa cla se de Cien cia en tra en cri sis ante los de sa - rro llos que han pues to a la Com ple ji dad en evi - den cia; no so la men te en los sis te mas muy com - pli ca dos y por ello “com ple jos” (lo que es de no - mi na do como `Com ple ji dad res trin gi da´, sino en los sis te mas de cual quier tipo (la `Com ple ji - dad ge ne ra li za da´. Com pren sión ésta de la Com ple ji dad fiel a su eti mo lo gía que data de `com ple xus´ como `lo te ji do en co mún´ y que avan za ha cia una nue va vi sión pa ra dig má ti ca de-la-con jun ción, que tras cien de el pa ra dig ma dis yun ti vo-ana lí ti co de la Cien cia mo der - na. Nue va vi sión en la que las no cio nes de `sis tema´, `emer gen cia´ y `caos´ ad quie ren nue vos sen ti dos y va lor heu rís ti co y que de be ría con du - cir nos ha cia una nue va en se ñan za que vuel va a reu nir las no cio nes que han que da do de sin te gra - das y ha cia una éti ca de la com pren sión.

  15. Declines in populations of Salix caprea L.during forest regeneration after strong herbivore pressure

    Janusz B. Faliński

    2014-02-01

    (Carpinus betulus, Tilia cordata, Acer platanoides and Ulmus glabra under the canopy of light-seeded trees, and the non-creation of a new generation of pioneer species points to the imminent end of the process of regeneration in the forest communities of Białowieża National Park.

  16. Relación costo-efectividad de las intervenciones preventivas contra el cáncer cervical en mujeres mexicanas Generalized cost-effectiveness of preventive interventions against cervical cancer in Mexican women: results of a Markov model from the public sector perspective

    Cristina Gutiérrez-Delgado

    2008-04-01

    Full Text Available OBJETIVO: Realizar un análisis de la relación costo-efectividad generalizada (ACEG para la vacuna anti-VPH, el tamiz por captura de híbridos (CH y el tamiz por Papanicolaou en el caso mexicano. MATERIAL Y MÉTODOS: Entre abril y agosto de 2007 se desarrolló en México un ACEG de las intervenciones relacionadas con 10 posibles escenarios en un modelo markoviano, bajo la perspectiva del sector público como pagador. RESULTADOS: Los escenarios con cobertura universal muestran un cociente costo-efectividad por AVISA ganado para el Papanicolaou en mujeres de 25 a 64 años de 16 678 pesos, para el tamiz por CH en mujeres de 30 a 64 años de 17 285 pesos y para la vacuna en niñas de 12 años de 84 008 pesos. El financiamiento anual necesario para estas intervenciones es de 621, 741 y 2 255 millones de pesos, respectivamente. CONCLUSIONES: Se sugiere introducir una combinación selectiva de tamices (Papanicolaou y CH y considerar las ventajas comparativas de aplicación en distintas poblaciones y áreas geográficas. De manera complementaria, se aconseja introducir la vacuna con un precio umbral de 181 pesos por dosis, equiparable en términos del costo y la efectividad a la CH.OBJECTIVE: To develop a generalized cost-effectiveness analysis (GCEA of the HPV vaccine, hybrid capture screening (HC and Papanicolaou screening (Pap in the Mexican context. MATERIALS AND METHODS: From April to August 2007, in Mexico, a GCEA of the interventions was developed for 10 possible scenarios using a Markov model from the public sector perspective as payer. RESULTS: Scenarios considering 80% coverage show an ACER per DALY averted of $16678 pesos for Pap of women between ages 25 and 64, $17277 pesos for HC of women between ages 30 and 64, and $84008 pesos for vaccination of 12-year-old girls. Annual financing of $621, $741 and $2255 million pesos, respectively, is needed for these scenarios. CONCLUSIONS: A selective, combined introduction of Pap-HC screening that

  17. Response of Vegetation in Northern China to Global Warming

    Cui, H.; Huang, R.

    2009-05-01

    During the last 30 years, the warmth index (WI) (Kira, 1945) has increased by 10 to 20 points in northern China and the humid index (HI) (Xu,1985) correspondingly decreased by 1 to 2 points. Accordingly, the green leaf stage of plants and herbs around Beijing prolonged from late Nov. to mid-Dec. The phenophase has also been changed, e.g., the most enjoyable period of red leaves such as common smoketree (Cotinus coggygria) and maple (Acer mono and A.truncatum) has postponed for 10 days and the blooming period of flowering plants has also advanced for the same span. Some plants, e.g. japanese pagodatree (Sophora japonica) and hispid locust (Robinia hispida) even blossom again in fall. Some evergreen and thermophilic plants have also been planted to further north. Rice (Oryza sativa) have extended to around 49 degree N and, as an extreme case, to 52 degree N (Huma County, Heilongjiang Province), and tea (Camellia sinensis) from around 35 to 36.5 degree N. River basins of Songhuajiang and Nenjiang in Heilongjiang Province become important rice production bases. Rizhao and Qingdao in Shandong province become famous tea production bases. Before 1970s, evergreen broadleaf woody plants were rarely cultivated in Beijing. But now such plants as privet (Lygustrum lucidum), magnolia (Magnolia grandiflora), evergreen euonymus (Euonymus japonicus), and boxwood (Buxus sinica var. margaritacea) all live there through the winter. Many thermophilic garden plants, such as fig (Ficus carica), Chinese tulip tree (Liliodendron chinense), Chinese photinia (Photinia serrulata), crape myrtle (Lagerstroemia indica), and plum blossom (Prunus mume) are also successively cultivated outdoors in Beijing. Common papermulberry (Broussonetia papirifera) gradually increases and even becomes subdominant species of deciduous forest during last 30 years in the piedmont around Beijing. The cultivation boundary of some thermophilic trees, e.g., Chinese catalpa (Catalpa ovata), japanese pagodatree

  18. 南瓜属植物离体茎段嫁接维管 组织的发育过程%Vascular development in the segment grafts of Cucurbita in Vitro

    王幼群; 杜中; 韩静

    2000-01-01

    The segment of hypocotyl from two species of Cucurbita were g rafted under sterile culture.The vascular development in the graft union from he terograft of C.pepo/C.moschata and autograft of C.moschata was examined by using light microscopy.The xylem and sieve elements were differentiated from the parenchyma cells in the scion and the stock,and the callus of the graft inte rface 6~8 days after grafting.8 days after grafting,the xylem and phloem bridges connecting the scion and stock were formed,and the number of vessels and sieve tubes in the graft interface increased along with the days after grafting.6(5)CF was used as a tracer to test the phloem connection of scion and stock during th e different period of development.It was found that 8 days after grafting the tr acer could be transported from the scion to the stock.%在离体条件下,采用南瓜属植物的下胚轴节段进行嫁接。光镜观察发现: 异种嫁接西葫芦/南瓜和南瓜自体嫁接嫁接后6~8 d在接穗、砧木的薄壁细胞和嫁接面处愈伤 组织细胞中分化出管状分子和筛分子,连接接穗和砧木的木质部和韧皮部桥在嫁接后8 d形 成。随后随发育天数的增加其数目增加。用6(5)CF作为筛管输导的示踪剂检验了不同发育时 期砧木和接穗间的连通情况,发现嫁接后8 d从接穗引入的6(5)CF可以输导到砧木。

  19. Seeing the Forest through the Trees: Considering Roost-Site Selection at Multiple Spatial Scales.

    David S Jachowski

    Full Text Available Conservation of bat species is one of the most daunting wildlife conservation challenges in North America, requiring detailed knowledge about their ecology to guide conservation efforts. Outside of the hibernating season, bats in temperate forest environments spend their diurnal time in day-roosts. In addition to simple shelter, summer roost availability is as critical as maternity sites and maintaining social group contact. To date, a major focus of bat conservation has concentrated on conserving individual roost sites, with comparatively less focus on the role that broader habitat conditions contribute towards roost-site selection. We evaluated roost-site selection by a northern population of federally-endangered Indiana bats (Myotis sodalis at Fort Drum Military Installation in New York, USA at three different spatial scales: landscape, forest stand, and individual tree level. During 2007-2011, we radiotracked 33 Indiana bats (10 males, 23 females and located 348 roosting events in 116 unique roost trees. At the landscape scale, bat roost-site selection was positively associated with northern mixed forest, increased slope, and greater distance from human development. At the stand scale, we observed subtle differences in roost site selection based on sex and season, but roost selection was generally positively associated with larger stands with a higher basal area, larger tree diameter, and a greater sugar maple (Acer saccharum component. We observed no distinct trends of roosts being near high-quality foraging areas of water and forest edges. At the tree scale, roosts were typically in American elm (Ulmus americana or sugar maple of large diameter (>30 cm of moderate decay with loose bark. Collectively, our results highlight the importance of considering day roost needs simultaneously across multiple spatial scales. Size and decay class of individual roosts are key ecological attributes for the Indiana bat, however, larger-scale stand

  20. Seeing the Forest through the Trees: Considering Roost-Site Selection at Multiple Spatial Scales.

    Jachowski, David S; Rota, Christopher T; Dobony, Christopher A; Ford, W Mark; Edwards, John W

    2016-01-01

    Conservation of bat species is one of the most daunting wildlife conservation challenges in North America, requiring detailed knowledge about their ecology to guide conservation efforts. Outside of the hibernating season, bats in temperate forest environments spend their diurnal time in day-roosts. In addition to simple shelter, summer roost availability is as critical as maternity sites and maintaining social group contact. To date, a major focus of bat conservation has concentrated on conserving individual roost sites, with comparatively less focus on the role that broader habitat conditions contribute towards roost-site selection. We evaluated roost-site selection by a northern population of federally-endangered Indiana bats (Myotis sodalis) at Fort Drum Military Installation in New York, USA at three different spatial scales: landscape, forest stand, and individual tree level. During 2007-2011, we radiotracked 33 Indiana bats (10 males, 23 females) and located 348 roosting events in 116 unique roost trees. At the landscape scale, bat roost-site selection was positively associated with northern mixed forest, increased slope, and greater distance from human development. At the stand scale, we observed subtle differences in roost site selection based on sex and season, but roost selection was generally positively associated with larger stands with a higher basal area, larger tree diameter, and a greater sugar maple (Acer saccharum) component. We observed no distinct trends of roosts being near high-quality foraging areas of water and forest edges. At the tree scale, roosts were typically in American elm (Ulmus americana) or sugar maple of large diameter (>30 cm) of moderate decay with loose bark. Collectively, our results highlight the importance of considering day roost needs simultaneously across multiple spatial scales. Size and decay class of individual roosts are key ecological attributes for the Indiana bat, however, larger-scale stand structural components

  1. Impact assessment of intermediate processes of steelmaking in electricity cogeneration of steel mill companies//Evaluación del impacto de los procesos intermedios de la producción de acero en la cogeneración de electricidad de la industria siderúrgica

    Eder Quental-de-Araújo

    2015-09-01

    Full Text Available La industria siderúrgica es uno de los sectores donde se consume mayor cantidad de energia, siendo responsable por la generación de productos resultantes de procesos con un alto valor energético agregado, entre los que se destacan los gases de proceso. Esos combustibles suministran parte de la demanda térmica de la siderúrgica y, típicamente, son aprovechados para la cogeneración de electricidad. De esta forma, aún con la gran cantidad y la alta complejidad de las variables que intervienen, fue aplicada una metodología clara y accesible desarrollada por Araújo (2015, para prever y simular la cogeneración de electricidad en un proceso típico de la industria siderúrgica. El objetivo de este trabajo es el de evaluar la sensibilidad de la cogeneración a la alteración de la producción de los procesos intermedios. Fue observado que algunos procesos como coquería, el alto horno y la acería, presentan una relación directa entre el aumento de la producción y la capacidad de cogeneración y, en otros procesos como la sinterización y la laminación, el incremento de la producción provoca una disminución de la disponibilidad de combustibles para la central termoeléctrica. Palabras claves: siderúrgica, previsión, cogeneración, gases de proceso, los procesos intermedios.______________________________________________________________________________AbstractThe steel industry is one of the most energy-intensive industry sectors, accounting also for the generation of co-products with high added energy, among them stands out the process gases. These fuels supply part of thermal demand from the steel mill companies and are typically utilized for cogeneration of electricity. Thus even with all the amount and complexity of variables involved, a clear and accessible methodology developed by Araujo was applied (2015 to predict and simulate the cogeneration of electricity. Therefore this study aims to evaluate the sensitivity of the change in

  2. How low can you go? Assessing minimum concentrations of NSC in carbon limited tree saplings

    Hoch, Guenter; Hartmann, Henrik; Schwendener, Andrea

    2016-04-01

    Tissue concentrations of non-structural carbohydrates (NSC) are frequently used to determine the carbon balance of plants. Over the last years, an increasing number of studies have inferred carbon starvation in trees under environmental stress like drought from low tissue NSC concentrations. However, such inferences are limited by the fact that minimum concentrations of NSC required for survival are not known. So far, it was hypothesized that even under lethal carbon starvation, starch and low molecular sugar concentrations cannot be completely depleted and that minimum NSC concentrations at death vary across tissues and species. Here we present results of an experiment that aimed to determine minimum NSC concentrations in different tissues of saplings of two broad-leaved tree species (Acer pseudoplatanus and Quercus petratea) exposed to lethal carbon starvation via continuous darkening. In addition, we investigated recovery rates of NSC concentrations in saplings that had been darkened for different periods of time and were then re-exposed to light. Both species survived continuous darkening for about 12 weeks (confirmed by testing the ability to re-sprout after darkness). In all investigated tissues, starch concentrations declined close to zero within three to six weeks of darkness. Low molecular sugars also decreased strongly within the first weeks of darkness, but seemed to stabilize at low concentrations of 0.5 to 2 % dry matter (depending on tissue and species) almost until death. NSC concentrations recovered surprisingly fast in saplings that were re-exposed to light. After 3 weeks of continuous darkness, tissue NSC concentrations recovered within 6 weeks to levels of unshaded control saplings in all tissues and in both species. To our knowledge, this study represents the first experimental attempt to quantify minimum tissue NSC concentrations at lethal carbon starvation. Most importantly, our results suggest that carbon-starved tree saplings are able to

  3. 吉林市松花江沿江绿地木本植物群落树种组成与α多样性%Species Composition and Alpha Diversity of Woody Plant Community in Green Space along Songhua River in Jilin City

    马赛; 孙晓刚; 丁言

    2015-01-01

    采用样方法,对吉林市松花江沿江绿地木本植物群落进行了调查研究。结果表明:共调查木本植物998棵,隶属于20科、34属、56种。裸子植物门中松科物种最多,被子植物门中蔷薇科物种最多。在绿化带群落乔木、灌木中东北杏、玫瑰分别具有最大的重要值,在游园群落乔木、灌木中家榆、接骨木分别具有最大的重要值,在亲水群落乔木、灌木中旱柳、茶条槭分别具有最大的重要值。 Menhinick、Margalef、Shannon-Wiener和Simpson指数均表现为绿化带群落>亲水群落>游园群落,而修正的Hill指数和Pielou指数表现为亲水群落>绿化带群落>游园群落。%The author investigated the species composition and alpha diversity of woody plant community in green space along the Songhua River in Jilin city through using quadrat method .The results indicated that a total of 998 woody plants were investiga-ted, and they belonged to 56 species, 34 genera and 20 families.In gymnosperm, Pinaceae had the most species .In angiosperm, Rosaceae had the most species .Armeniaca mandshurica and Rosa rugosa had the highest importance value in green belt community;Ulmus pumila and Sambucus williamsii had the highest importance value in garden community;Salix matsudana and Acer ginnalahad the highest importance value in waterfront community .The Menhinick index , Margalef index , Shannon-Wiener index and Simpson index of various woody plant communities all showed the following sequence :green belt community>waterfront community>garden community, while the modified Hill index and the Pielou index revealed the following order:waterfront community>green belt com-munity>garden community .

  4. Enhanced transpiration by riparian buffer trees in response to advection in a humid temperate agricultural landscape

    Hernandez-Santana, V.; Asbjornsen, H.; Sauer, T.; Isenhart, T.; Schilling, K.; Schultz, Ronald

    2011-01-01

    Riparian buffers are designed as management practices to increase infiltration and reduce surface runoff and transport of sediment and nonpoint source pollutants from crop fields to adjacent streams. Achieving these ecosystem service goals depends, in part, on their ability to remove water from the soil via transpiration. In these systems, edges between crop fields and trees of the buffer systems can create advection processes, which could influence water use by trees. We conducted a field study in a riparian buffer system established in 1994 under a humid temperate climate, located in the Corn Belt region of the Midwestern U.S. (Iowa). The goals were to estimate stand level transpiration by the riparian buffer, quantify the controls on water use by the buffer system, and determine to what extent advective energy and tree position within the buffer system influence individual tree transpiration rates. We primarily focused on the water use response (determined with the Heat Ratio Method) of one of the dominant species (Acer saccharinum) and a subdominant (Juglans nigra). A few individuals of three additional species (Quercus bicolor, Betula nigra, Platanus occidentalis) were monitored over a shorter time period to assess the generality of responses. Meteorological stations were installed along a transect across the riparian buffer to determine the microclimate conditions. The differences found among individuals were attributed to differences in species sap velocities and sapwood depths, location relative to the forest edge and prevailing winds and canopy exposure and dominance. Sapflow rates for A. saccharinum trees growing at the SE edge (prevailing winds) were 39% greater than SE interior trees and 30% and 69% greater than NW interior and edge trees, respectively. No transpiration enhancement due to edge effect was detected in the subdominant J. nigra. The results were interpreted as indicative of advection effects from the surrounding crops. Further, significant

  5. The Features of Naturalization of Invasive Fraction of Flora in the Voronezh Region and in Some Regions of the European Part of Russia

    Vladimirov D.R.

    2015-10-01

    Full Text Available The article is about naturalization features of invasive fraction of flora in Voronezh and some other regions of the European part of Russia. The summary table represents all invasive and potentially invasive plants of the European part of Russia with their level of naturalization (or invasive status. Invasive fraction of flora in the Voronezh region numbers 120 plants. All of them are on different stages of naturalization process in an anthropogenic areal. Invasive plants represent by agriophyts – 41 (34,1 % species, epecophyts – 75 (62,5 % species and colonophyts-epecophyts – 4 (3,4 % species. Totally there are 201 species of invasive and potentially invasive plants spread within European part of Russia (Northern-West Russia, Ivanovo, Kaluga, Tver, and Voronezh regions. They formed the “black list” of European Russia. 10 species are common to all invasive fractions. These are Acer negundo, Amelanchier x spicata, Aster x salignus, Echinocystis lobata, Elodea canadensis, Heracleum sosnowskyi, Impatiens glandulifera, Impatiens parviflora, Juncus tenuis and Lupinus polyphyllus. The analysis of the general list of invasive fractions of European Russia shows that 120 species of the list are invasive or potentially invasive in the Voronezh region (100 and 20 species in accordance, adventives naturalized species – 31, native species – 19, archaeophyts – 2, apophyts – 4. 26 species from the list were not found in the Voronezh region. Apparently, the region is a transit area for many invasive plants, which migrate from South to North, from East to West etc. Not only its natural and climatic potential, but also high level of transformation of local landscapes enabled immigrant-plants to naturalize within the bounds of the region. Furthermore, for many years the Voronezh region was the center of introduction of alien plants. Many of those became a part of invasion fraction of regional flora. In recent decades green building took place of

  6. Trophic-metabolic activity of earthworms (Lumbricidae as a zoogenic factor of maintaining reclaimed soils’ resistance to copper contamination

    Y. L. Kulbachko

    2014-07-01

    Full Text Available Soil contamination by heavy metals, first of all, influences biological and ecological conditions, and it is able to change the conservative soil features, such as humus content, aggregation, acidity and others, leading to partial or total diminishing of soil fertility and decrease in soil economic value. Zoogenic issues of soil protective capacity formation in conditions of heavy metal content rise under technogenesis have been studied. The article discusses the features of earthworm trophic-metabolic activity in the afforested remediated site (Western Donbass, Ukraine with different options of mixed soil bulk. Western Donbass is the large center of coal mining located in South-Western part of Ukraine. High rates of technical development in this region lead to surface subsidence, rising and outbreak of high-mineralized groundwater, and formation of dump pits of mine wastes. Remediated area is represented by the basement of mine wastes covered by 5 options of artificial mixed soil with different depth of horizons. The following tree species were planted on top of artificial soil: Acer platanoides L., Robinia pseudoacacia L., and Juniperus virginiana L. The main practical tasks were to define on the quantitative basis the buffer capacity of artificial mixed soil and earthworm excreta in relation to copper contamination and to compare its immobilization capacity in conditions of artificial forest plants in the territory of Western Donbass. It was proved that earthworm excreta had a great influence on soil immobilization capacity (particularly, on soil buffering to copper which increased for excreta in the following range: humus-free loess loam – top humus layer of ordinary chernozem. Immobilization efficiency of copper by earthworm excreta from ordinary chernozem bulk compared with baseline (ordinary chernozem was significantly higher. It should be noted that trophic-metabolic activity of earthworms plays very important role as a zoogenic factor

  7. Short Rotation Forestry (SRF in a Mediterranean Environment Under Limited Energy Inputs

    Stella Lovelli

    2010-12-01

    Full Text Available The aim of this work is comparing the two year performance (diameter, total height and mortality of twenty tree and shrub species in a semi arid environment. The research also wants to supply recommendation on the agronomic cropping techniques in areas where rainfall is the main limiting factor and water use is strictly limited. Woody biomass is gaining increasing importance for energy production in Italy. During the last five years, roughly 5000 ha of Short Rotation Forestry (SRF have been planted, mostly in northern Italy, especially using poplar clones. However, in Southern Italy, due to the poor rainfall and the lack of knowledge existing on the species to use, few groves have been established. The studied groves were set in December 2005 in a Mediterranean area where the total year rainfall is not higher than 600 mm (mostly in autumn and winter. Twenty species (Salix cinerea, Ulmus carpinifolia, Corylus avellana, Spartium junceum, Acer saccharinum, Morus alba, Saphora japonica, Eleagnus angustifolia, Fraxinus angustifolia (var oxicarpa, Sambucus nigra, Robinia pseudoacacia, Populus nigra, Albizia julibrissis, Populus alba, Salix alba, Ailanthus altissima, Alnus cordata, Ficus carica, Eucalyptus camaldulensis, Celtis australis were planted in “collection” plots and set in singular plots on single rows (3 m X 0.5 m spacing. Six species (R. pseudoacacia, P. nigra, P. alba, S. nigra, E. camaldulensis, and A. altissima were planted in eighteen random “experimental” split-plots, using single and twin rows (0.5 m spacing between plants. Plots had a rectangular plant spacing (3 m between singular and twin rows, 0.5 m on each row. Plant density was roughly 6670 cuttings ha-1 in “collection” plots with singular rows and 10950 cuttings ha-1 in “experimental” plots using single and twin rows. The expected harvest interval ranges from 2 to 5 years, depending on the first results. In the “collection” plots, the first results showed

  8. A Monte-Carlo maplet for the study of the optical properties of biological tissues

    Yip, Man Ho; Carvalho, M. J.

    2007-12-01

    Monte-Carlo simulations are commonly used to study complex physical processes in various fields of physics. In this paper we present a Maple program intended for Monte-Carlo simulations of photon transport in biological tissues. The program has been designed so that the input data and output display can be handled by a maplet (an easy and user-friendly graphical interface), named the MonteCarloMaplet. A thorough explanation of the programming steps and how to use the maplet is given. Results obtained with the Maple program are compared with corresponding results available in the literature. Program summaryProgram title:MonteCarloMaplet Catalogue identifier:ADZU_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADZU_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.:3251 No. of bytes in distributed program, including test data, etc.:296 465 Distribution format: tar.gz Programming language:Maple 10 Computer: Acer Aspire 5610 (any running Maple 10) Operating system: Windows XP professional (any running Maple 10) Classification: 3.1, 5 Nature of problem: Simulate the transport of radiation in biological tissues. Solution method: The Maple program follows the steps of the C program of L. Wang et al. [L. Wang, S.L. Jacques, L. Zheng, Computer Methods and Programs in Biomedicine 47 (1995) 131-146]; The Maple library routine for random number generation is used [Maple 10 User Manual c Maplesoft, a division of Waterloo Maple Inc., 2005]. Restrictions: Running time increases rapidly with the number of photons used in the simulation. Unusual features: A maplet (graphical user interface) has been programmed for data input and output. Note that the Monte-Carlo simulation was programmed with Maple 10. If attempting to run the simulation with an earlier version of Maple

  9. Simulated Nitrogen Deposition Reduces the Abundance of Dominant Forest Understory and Groundcover Plants

    Talhelm, A. F.; Burton, A. J.; Pregitzer, K. S.; Zak, D. R.

    2012-12-01

    Growth in global industrialization is expected to increase the amount of atmospheric N deposition added to terrestrial ecosystems during the next century (Dentener et al. 2006). In North America, northern temperate forests in the eastern half of the U.S. and Canada have received large amounts of N deposition for several decades and there is evidence that these consistent inputs of atmospheric N have increased the availability of N in these forests (Talhelm et al. 2012). Groundcover plants (seedlings, shrubs, and herbaceous plants) are considered to be more sensitive indicators of N deposition impacts than overstory trees (Pardo et al. 2011). Further, these plants are both crucial to forest regeneration following disturbance and, relative to their biomass, disproportionately important within forest ecosystems in terms of species diversity, net primary productivity, nutrient cycling, and litter production (Gillam 2007). In order to understand the effects of chronic N deposition on forests in the north-central United States, we have experimentally added 3 g N m-2 yr--1 in the form of NaNO3 pellets to plots at four northern hardwood forest sites spread across 500 km in Michigan since 1994. From 2005 to 2012, we have made repeated measurements of the abundance of both groundcover plants (1.4 m in height, less than 5 cm diameter at 1.4 m). At these sites, sugar maple (Acer saccharum) ) seedlings are highly abundant (up to 200 plants m-2) and the dominant groundcover plant (79% of all woody stems). Hop-hornbeam (Ostrya virginiana) is the dominant understory plant (42% of all stems). Experiment N additions strongly and consistently reduced the abundance of these two plants in these forest strata at the sites where these plants were most abundant. For sugar maple seedlings, there were significant effects at sites A (-49%) and C (-65%, Site × N: P germination (P = 0.296), but did reduce the number of seedlings that survived the first growing season (P = 0.001) and over the

  10. Variability of BVOC emissions from a Mediterranean mixed forest in southern France with a focus on Quercus pubescens

    A.-C. Genard-Zielinski

    2014-06-01

    Full Text Available We aimed at quantifying Biogenic Volatiles Organic Compounds (BVOC emissions in June from three Mediterranean species located at the O3HP site (Southern France: Quercus pubescens, Acer monspessulanum and C. coggygria (for isoprene only. As Q. pubescens was shown to be the main BVOC emitter with isoprene representing ≈ 99% of the carbon emitted as BVOC, we mainly focused on this species. C. coggygria was found to be a non-isoprene emitter (no other BVOC were investigated. To fully understand both the canopy effect on Q. pubescens isoprene emission and the inter-individual variability (tree to tree and within canopy, diurnal variations of isoprene were investigated from nine branches (seven branches located to the top of canopy at ≈ 4 m Above Ground Level, and two inside the canopy at ≈ 2 m a.g.l.. Q. pubescens daily mean isoprene emission rates (ERd fluctuated between 23.1 and 97.7 μg C gDM−1 h−1 and were exponentially correlated with net assimilation (Pn. Q. pubescens daily mean Pn ranged between 5.4 and 13.8, and 2.8 and 6.4 μmol CO2 m−2 s−1 for sunlit and shaded branches respectively. Both ERd and isoprene emission factors (Is assessed according to Guenther et al. (1993 algorithm, varied by a factor of 4 among the sunlit branches. While sunlit branches ERm was clearly higher than for shaded branches, there was an non-significant variability on Is (58.5 to 76.5 μg C gDM−1 h−1. Diurnal variations of isoprene emission rates (ER for sunlit branches were also investigated. ER were detected at dawn 2 h after Pn became positive and, exponentially dependent on Pn. Diurnal variations of ER were not equally well described along the day by temperature (CT and light (CL parameters according to G93 algorithm. Temperature had more impact than PAR in the morning emission increase. ER was no more correlated to CL × CT between solar noon (maximum ER and mid-afternoon, possibly due to thermal stress of the plant. A comparison between

  11. Elevated stream inorganic nitrogen impacts on a dominant riparian tree species: Results from an experimental riparian stream system

    Hultine, K. R.; Jackson, T. L.; Burtch, K. G.; Schaeffer, S. M.; Ehleringer, J. R.

    2008-12-01

    The release of inorganic nitrogen from intensive agricultural practices and urbanization has resulted in significant alterations of the aquatic nitrogen cycle in riparian ecosystems. Nevertheless, impacts of stream nitrogen inputs on the terrestrial nitrogen cycle and the water and carbon cycles are unclear. Information on terrestrial ecosystem responses to stream N loading is largely absent in part because of the difficulty in controlling for temporal and spatial variation in streamflow, geomorphology, climate, and vegetation. To address these issues, we constructed a dual-plot artificial stream riparian system within a 10-year-old plantation of a dominant riparian tree species, box elder (Acer negundo). The dual-plot design allowed for different concentrations of stream inorganic nitrogen between plots while controlling for ecohydrologic and geohydrologic variability. The system was used to investigate elevated inorganic stream nitrogen impacts on water use patterns, above-ground productivity, and leaf chemistry of streamside box elder trees over two consecutive growing seasons (2006 and 2007). One plot received inorganic soluble fertilizer that brought the NO3 concentration of stream water from 5 μmol l-1 to about 100 μmol l-1, while the second plot received no additional nitrogen. Relative stem sap flux density (Js) did not vary between plots until near the conclusion of the 2006 growing season, when trees in the fertilized plot showed a steep upswing in Js relative to trees in the control plot. Sap flux in 2007 increased consistently by 0.4% day-1 in the fertilized plot relative to the control plot over a 75-day period, before leveling off near the conclusion of the growing season. At the onset of the experiment, leaf nitrogen per unit mass and leaf nitrogen per unit area were significantly higher in the control plot, and leaf C:N ratios were lower. In 2007, however, differences in leaf chemistry disappeared, suggesting that leaf nitrogen increased in the

  12. Biology and host associations of redbay ambrosia beetle (Coleoptera: Curculionidae: Scolytinae), exotic vector of laurel wilt killing redbay trees in the southeastern United States.

    Hanula, James L; Mayfield, Albert E; Fraedrich, Stephen W; Rabaglia, Robert J

    2008-08-01

    The redbay ambrosia beetle, Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae), and its fungal symbiont, Raffaelea sp., are new introductions to the southeastern United States responsible for the wilt of mature redbay, Persea borbonia (L.) Spreng., trees. In 2006 and 2007, we investigated the seasonal flight activity of X. glabratus, its host associations, and population levels at eight locations in South Carolina and Georgia where infestations ranged from very recent to at least several years old. Adults were active throughout the year with peak activity in early September. Brood development seems to take 50-60 d. Wood infested with beetles and infected with the Raffaelea sp. was similar in attraction to uninfested redbay wood, whereas both were more attractive than a nonhost species. Sassafras, Sassafras albidium (Nutt.) Nees, another species of Lauraceae, was not attractive to X. glabratus and very few beetle entrance holes were found in sassafras wood compared with redbay. Conversely, avocado, Persea americana Mill., was as attractive to X. glabratus as swampbay, P. palustris (Raf.) Sarg., and both were more attractive than the nonhost red maple, Acer rubrum L. However, avocado had relatively few entrance holes in the wood. In 2007, we compared X. glabratus populations in areas where all mature redbay have died to areas where infestations were very active and more recent. Trap catches of X. glabratus and numbers of entrance holes in trap bolts of redbay were correlated with the number of dead trees with leaves attached. Older infestations where mature host trees had been eliminated by the wilt had low numbers of beetles resulting in trap catches ranging from 0.04 to 0.12 beetles per trap per d compared with 4-7 beetles per trap per d in areas with numerous recently dead trees. Our results indicate beetle populations drop dramatically after suitable host material is gone and provide hope that management strategies can be developed to restore

  13. Evaluation of selected wild plants flowering season 1991 - 2009 (1991 - 2000 & 2001 - 2009)

    Hajkova, L.; Nekovar, J.; Novak, M.; Richterova, D.

    2009-09-01

    The subsequent wild plants are observed by volunteer observers at CHMI phenological network: CALTHA palustris L., ANEMONE nemorosa L., HEPATICA nobilis Mill., RANUNCULUS acer L., FRAGARIA vesca L., TRIFOLIUM repens L., HYPERICUM perforatum L., CHAMAENERION angustifolium L. Holub, VACCINIUM myrtillus L., LAMIUM album L., CHRYSANTHEMUM leucanthemum L., TUSSILAGO farfara L., PETASITES albus (L.) Gaert., PETASITES hybridus (L.) G. M. Sch., CONVALLARIA majalis L., GALANTHUS nivalis L., DACTYLIS glomerata L., ALOPECURUS pratensis L. and others. Some of them start to blossom in early spring, some others in the summer. Part of them belong to very important allergens, part of them have medicinal effects. Phenophases first leaves (FL - BBCH11), inflorescence emergence (IE - BBCH 51), beginning and end of flowering (BF - BBCH 61, EF - BBCH 69) are observed by these species. Statistical parameters (average, median, lower quartile, upper quartile, minimum, maximum, standard deviation, variation range and variation coefficient) of phenophase onset are computed from all of phenological stations in Czechia for the period 1991 - 2009. The phenophase onset and phenophase duration depend not only on genetic base but also on external effects such as weather. We have compiled dynamics of temperature to phenophase onset according CHMI meteorological stations for the same period 1991 - 2009 (especially sums of active temperatures above biological minimum 5°C and progression of extreme temperatures). We have also compared results between two periods (1991 - 2000, 2001 - 2009). Phenological stations are at different altitude. At this case study were used results from 4 phenological stations at altitude ( 500 m asl). GALANTHUS nivalis L. Station: Lednice (165 m n. m.) Period: 1991 - 2000 Statistical parameter/phenophase BBCH 61 BBCH 69 Average 62 94 Median 60 97 Lower quartile 57 86 Upper quartile 66 101 Minimum 51 70 Maximum 79 116 Variation range 28 46 Standard deviation 8,6 12

  14. Аллелопатическая активность листового опада древесных растений, почвы и копролитов в парках г. Днепропетровск

    Анжелина Илларионовна Крючкова

    2014-11-01

    Full Text Available В работе рассматривается влияние аллелопатических свойств опада древесных растений и трофометаболической деятельности дождевых червей (Lumbricidae на аллелопатические свойства почвы под древесными породами Acer platanoides L., Aesculus hippocastanum L., Ulmus minor Mill. в парках г. Днепропетровск. Установлено, что трофометаболическая деятельность червей положительно влияет на аллелопатический статус почв.

  15. АЛЛЕЛОПАТИЧЕСКАЯ АКТИВНОСТЬ ЛИСТОВОГО ОПАДА ДРЕВЕСНЫХ 20РАСТЕНИЙ, ПОЧВЫ И КОПРОЛИТОВ В ПАРКАХ Г. ДНЕПРОПЕТРОВСК

    Крючкова, А.; Кульбачко, Ю.

    2014-01-01

    В работе рассматривается влияние аллелопатических свойств опада древесных растений и трофометаболической деятельности дождевых червей (Lumbricidae) на аллелопатические свойства почвы под древесными породами Acer platanoides L., Aesculus hippocastanum L., Ulmus minor Mill. в парках г. Днепропетровск. Установлено, что трофометаболическая деятельность червей положительно влияет на аллелопатический статус почв.The article examines the impact of leaf litter allelopathic properties and earthworms t...

  16. Uptake of 207Pb and 111Cd through bark of mature sugar maple, white ash and white pine: a field experiment

    Cd and Pb uptake by bark is not likely to be a major contribution to metal burdens in tree xylem. - A field study was undertaken to determine whether 207Pb and 111Cd, applied to the exterior bark of sugar maple (Acer saccharum Marsh.), white ash (Fraxinus americana L.) and white pine (Pinus strobus L.), could enter xylem tissue. Stable isotope tracers (3 μg Pb ml-1; 2 μg Cd ml-1) were applied separately to bark in simulated rainfall, acidified to pH 4.5, in multiple doses over a 4 month (July-October) period. Tree cores were extracted from the region of application in the following March, and Pb and Cd isotopes were measured in bark and the outer tree rings using inductively coupled plasma mass spectrometry. The majority of the applied stable isotope tracer recovered (over 94%) was present in bark tissue, although a small amount of each metal tracer entered the outer (1-3) tree rings in all trees. Despite high concentrations of excess 207Pb in bark (up to 50 μg g-1), the maximum concentration of excess 207Pb measured in tree rings was only around 50 ng g-1, which represents less than 30% of the background Pb concentration in wood at the study site. High excess 111Cd concentrations in bark (up to 35 μg g-1) also resulted in small increases in 111Cd in wood (up to 50 ng g-1), but due to lower background Cd concentrations in wood, such increases more than doubled the amount of Cd in wood compared with background levels. However, at sites where such high bark Cd concentrations are found, uptake from Cd-contaminated soil would probably be much greater than found at our study site. It appears that Cd and Pb applied to bark can enter woody tissue, but that this route of uptake is likely to be a minor contributor to the metal burden in wood

  17. Vegetation Diversity Quality in Mountainous Forest of Ranu Regulo Lake Area, Bromo Tengger Semeru National Park, East Java

    Jehan Ramdani Hariyati

    2012-01-01

    Full Text Available Aim of this research was to study vegetation diversity quality in mountainous forest of Ranu Regulo Lake area in Bromo Tengger Semeru National Park (TNBTS, East Java. Field observation was carried out by vegetation analysis using sampling plots of 25x25 m2 for trees, 5x5 m2 for poles, 1x1 m2 for ground surface plants. Community structure of each lake side was determined by calculating vegetation's density, basal area, frequency, important value and stratification of species. While vegetations diversity was estimated by taxa richness, Shannon-Wiener diversity index, and rate of endemism. Each lake side forests were compared by Morisita community similarity index. Data were tabulated by Microsoft Excel 2007. The result showed that based on existed vegetation, mountainous forest surrounding Ranu Regulo Lake consisted of four ecosystems, i.e. heterogenic mountainous forest, pine forest, acacia forest and bushes. Bushes Area has two types of population, edelweiss and Eupatorium odoratum invaded area. Vegetation diversity quality in heterogenic mountainous forest of Ranu Regulo TNBTS was the highest, indicated by its multi-stratification to B stratum trees of 20-30m high. Heterogenic mountainous forest’s formation was Acer laurinum and Acmena accuminatissima for trees, Chyatea for poles. Taxa richness was found 59 species and 30 families, while the others were found below 28 species and 17 families. Diversity Index of heterogenic mountainous forest is the highest among others for trees is 2.31 and 3.24 for poles and second in bushes (H=3.10 after edelweiss ecosystem (H=3.39. Highest rate of endemism reached 100% for trees in heterogenic mountainous forest, 87% for poles in edelweiss area and 89% for bushes also in heterogenic mountainous forest. Trees, poles and herbs most similarity community showed by pine and acacia forest. Based on those five characters, vegetation diversity quality in Ranu Regulo Lake area was medium for heterogenic mountainous

  18. Seedling Growth and Phosphorus Cycling in Northern Forest Soils Amended With Biochar and Wood Ash

    Noyce, G. L.; Jones, T.; Fulthorpe, R.; Basiliko, N.

    2015-12-01

    Biochar may be a powerful soil amendment to reduce nutrient depletion in North American forests where long-term nitrogen deposition has led to phosphorus (P) limitation, but many effects of biochar in these ecosystems are still unknown. We performed a 12-week growth chamber experiment in which red pine (Pinus resinosa) and sugar maple (Acer saccharum) seedlings were grown in pots with soil from three Ontario forests and varying amounts of sugar maple biochar. Additionally, biochar effects were compared with the effects of wood ash, a forest biomass bioenergy by-product that may also be a beneficial soil amendment in these ecosystems. We assessed plant biomass, soil microbial biomass and phosphatase activity; additional chemical analyses of plant tissue and soils are ongoing. Biochar effects on seedling growth were not consistent across tree species, soil type, and addition rate. For sugar maple seedlings grown in sand and sandy-loam textured soils, biochar additions of 20 t ha-1 significantly (p = 0.03) decreased root biomass by 25 %, and the root-to-shoot ratio correspondingly declined, but this effect was not observed in a silty soil. For red pine seedlings, the same biochar addition rate slightly increased root biomass. Wood ash effects on biomass were similarly variable. For example, in the sandy soil, sugar maple root biomass was significantly lower after application of 16 t ash ha-1, but unchanged by rates of 4 or 40 t ash ha-1. Microbial biomass and soil phosphatase activity also varied by soil type. Phosphatase activity was significantly lower (p = 0.02) in soils with sugar maple compared to red pine, but there were no consistent biochar or ash effects across all soils and species. However, for red pine seedlings grown in silt, biochar significantly (p = 0.04) reduced the phosphatase activity compared to the control and ash soils. Overall, biochar may lessen P-limitation in forested ecosystems, but the suitability of biochar, and wood ash, for increasing P

  19. Application of statistical correction in extended weather forecasting in the southern region of Brazil Aplicação de correlações estatísticas nas previsões de tempo estendidas na região Sudeste do Brasil

    Ana Maria Heuminski de Avila

    2012-12-01

    resultados do modelo corrigido e sem correção apresentam uma alta acerácea, indicando que o modelo de previsão de tempo por conjunto pode apresentar-se como uma ferramenta auxiliar para o monitoramento das safras agrícolas.

  20. La objetividad entre paréntesis: A propósito de Humberto Maturana

    Jorge Liberati

    2007-01-01

    Full Text Available Re tro tra yén do se a los tra ba jos ini cia les de Hum ber to Ma tu ra na acer ca de las con di cio nes bá si cas del ori gen de la Vida a tra vés de la con - jun ción de `clau su ra´, `au to no mía´ y `es truc tu ra - ción´ de una pri mi ge nia cé lu la en tan to sis te ma `au to poié ti co´, se avan za ha cia un co men ta rio pa no rá mi co de dos cam pos cen tra les en los tra ba - jos ul te rio res del pen sa dor chi le no ha cia los que éste pro yec ta el pro ce so au to poié ti co: la rea li dad fí si ca y el co no ci mien to hu ma no. Lo que lo lle va a abor dar una con cep cion de los sis te mas so cia - les y su sur gi mien to (en la que se ins pi ra ra Ni klas Luh mann, y a un tra ta mien to de la `ob je ti vi - dad´ (que po dría ha ber te ni do un pre ce den te en Leib nitz en tér mi nos de `do mi nios de coor di na - ción de ac cio nes´ tra ma das en el len gua je, a par - tir de cons ti tuir nos en `ob ser va do res´ que tri bu - tan a una Cien cia para la com pren sión de la na tu - ra le za y no para su con trol y do mi nio, y a una con duc ta so cial no de com pe ten cia sino de coo - pe ra ción.

  1. Simulated Impacts of Emerald Ash Borer on Throughfall and Stemflow Inputs of Water and Nitrogen in Black Ash Wetlands in Northern Michigan

    Pypker, T. G.; Davis, J.; Van Grinsven, M. J.; Bolton, N. W.; Shannon, J.; Kolka, R. K.; Nelson, J.; Wagenbrenner, J. W.

    2014-12-01

    Emerald ash borer (Agrilus planipennis Fairmaire (EAB)) is an invasive insect that effectively kills ash trees (genus: Fraxinus) greater than 2.5 cm in diameter, resulting in near-complete stand mortality within 3-4 years. Black ash wetlands occupy approximately 270,000 ha in Michigan, and have 40 to 90% of the basal area occupied by black ash (F. nigra Marshall); hence the loss of black ash may result in dramatic changes in the canopy hydrology and nutrient deposition. We assessed the impact of a simulated EAB invasion on throughfall and stemflow quantity and nitrogen (N) content in 9 uninfected black ash wetlands located in the Upper Peninsula of Michigan. Within the 9 stands, 3 stands were left untreated ('Control'), 3 stands had all the black ash trees manually girdled ('Girdled') and 3 had all the black ash trees felled by chainsaw ('Clearcut'). We measured the quantity and inorganic-N content of throughfall using an array of randomly placed collectors (n = 16 per site). Stemflow was monitored at 2 sites (n = 12 trees) on the 3 most common tree species (black ash, yellow birch (Betula alleghaniensis Britt.) and red maple (Acer rubra L.)). Preliminary results indicate that relative to the Control, average monthly throughfall was 25% and 1% greater in the Clearcut and Girdled sites, respectively. While the loss of the ash trees resulted in greater throughfall inputs in the Clearcut sites, water table heights did not significantly change as a result of the treatments. Stemflow from live black ash trees was lower than from the yellow birch and red maple trees. As a result, we predict stemflow will increase over time as species with smoother bark and less upright branching begin replacing the black ash. Hence, the change in tree species may result in a greater concentration of inorganic-N inputs to the base of the trees, thereby altering the distribution of inorganic-N inputs into the wetland. Our preliminary results show no significant change in the total

  2. Combination of different methods to assess the fate of lignin in decomposing needle and leave litter

    Klotzbücher, Thimo; Filley, Timothy; Kaiser, Klaus; Kalbitz, Karsten

    2010-05-01

    Lignin is a major component of plant litter. However, its fate during litter decay is still poorly understood. One reason is the difficult analysis. Commonly used methods utilize different methodological approaches and focus on different aspects, e.g., content of lignin and/or of lignin-derived phenols and the degree of oxidation. The comparability and feasibility of the methods has not been tested so far. Our aims were: (1) to compare different methods with respect to track lignin degradation during plant litter decay and (2) to evaluate possible advantages of combining the different results. We assessed lignin degradation in decaying litter by 13C-TMAH thermochemolysis and CuO oxidation (each combined with GC/MS) and by determination of acid-detergent lignin (ADL) combined with near infrared spectroscopy. Furthermore, water-extractable organic matter produced during litter decay was examined for indicators of lignin-derived compounds by UV absorbance at 280 nm, fluorescence spectroscopy, and 13C-TMAH GC/MS. The study included litter samples from 5 different tree species (acer, ash, beech, pine, spruce), exposed in litterbags to degradation in a spruce stand for 27 months. First results suggested stronger lignin degradation in coniferous than in deciduous litter. This was indicated by complementary results from various methods: Conifer litter showed a more pronounced decrease in ADL content and a stronger increase in oxidation degree of side chains (Ac/Al ratios of CuO oxidation and 13C-TMAH products). Furthermore water extracted organic matter from needles showed a higher aromaticity and molecule complexity. Thus properties of water extractable organic matter seemed to reflect the extents of lignin degradation in solid litter samples. Contents of lignin-derived phenols determined with the CuO method (VSC content) hardly changed during decay of needles and leaves. These results thus not matched the trends found with the ADL method. Our results suggested that water

  3. Reinvestigation of the Miocene palynoflora from the Daotaiqiao Formation of north-eastern China using SEM

    Akyurt, Elvan; Grímsson, Friðgeir; Zetter, Reinhard; Leng, Qin; Bouchal, Johannes Martin

    2016-04-01

    Here we report the first results of an ongoing study on the Miocene palynoflora from the Daotaiqiao Formation of north-eastern China. Using the single grain technique, we examined individual pollen and spores using both light and scanning electron microscopy. A previous study by Grímsson et al. (2012) on Onagraceae pollen grains from this locality, using the same technique identified five different species. Such a variety of Onagraceae from a single palynoflora is unknown elsewhere. The ongoing study suggests a remarkably rich pollen and spore flora with at least 15 different types of spores, one Ginkgo and one Ephedra type pollen, 11 conifer pollen types and approximately 145 angiosperm pollen types. Spores are very rare in the samples (≤1%). Conifer pollen grains are regularly observed but are not a dominant component (ca. 16 %). The samples yield a high quantity and diversity of angiosperm pollen (ca. 80%). The conifers include representatives of Cupressaceae (2 spp.), Pinaceae (Larix, Picea, Pinus, Tsuga) and Sciadopityaceae. The angiosperm pollen cover at least 40 families. Prominent elements are pollen of the Betulaceae (Alnus, Betula, Carpinus, Corylus), Cercidiphyllaceae (Cercidiphyllum), Ericaceae (8 spp.), Eucommiaceae (Eucommia), Fagaceae (Fagus, Quercus spp., Castaneoideae), Juglandaceae (Carya, Cyclocarya, Juglans, Pterocarya), Rosaceae (11 spp.), Sapindaceae (Acer, Aesculus) and Ulmaceae (Hemiptelia, Ulmus, Zelkova). The high angiosperm pollen diversity indicates a varying landscape with a relatively high variety of niches including riparian, dry and mesic forests. Most of the potential modern analogues of the fossil taxa are currently thriving under humid temperate (Cfa- and Cwa)-climates, pointing to paleoclimate conditions not unlike those found today in the lowlands and adjacent mountain regions of the (south-) eastern United States, the humid-meridional region of western Eurasia, and central and southern China, and Honshu (Japan). References

  4. Predicted distribution of visible and near-infrared radiant flux above and below a transmittant leaf

    The effects of background reflectance, leaf size, and leaf height above the background on upward and downward radiant flux (φu and φd) from a leaf were investigated using a computer model of a horizontal, isotropically scattering leaf. This research was conducted to determine how these variables influence the light environment above, below and adjacent to a leaf. Leaf spectral properties for big-leaf maple (Acer macrophyllum) were measured in the laboratory and used in the model. Model results were reported as relative radiant flux (φr), defined as a percentage of the light entered into the model. The model showed that upward relative radiant flux φur from a leaf was highly dependent on the reflectance of the background and the wavelength of light. The greatest variation in φur was observed in the near infrared (NIR). The φur also varied depending upon the height of the leaf above the background and the size of the leaf. Leaves were brightest when placed the farthest distance above the background. Small leaves reached maximum brightness at lower heights than larger leaves. Finally, φur varied spatially. Leaf edges reflected more light than the leaf center except for leaves positioned very close to the background. Additional studies using the model showed that the intensity of light within a leaf shadow varied spatially, with the greatest downward relative radiant flux φdr, occurring directly below the center of the leaf. Furthermore, φdr within the shadow cast by the leaf decreased as the height of the leaf above the background increased. The rate of decrease depended upon the size of the leaf. The smaller the leaf, the greater was the change in φdr with change in leaf height. These results imply that NIR canopy reflectance, due to leaf transmittance, may be highly dependent upon the reflectance of its background. Furthermore, architecturally different canopies may show different degrees of dependence upon background reflectance in the NIR. These results

  5. Importance of Forest Composition on Mercury Deposition through Litterfall and Accumulation in Soils

    Juillerat, J. I.; Ross, D. S.

    2010-12-01

    Upland forests receive greater atmospheric deposition of mercury (Hg) than non-forested areas. In addition to wet deposition of Hg, forests are subjected to Hg deposition in throughfall and litterfall: dry deposition to leaves may be subsequently leached in throughfall; elemental Hg may enter leaves and be later deposited in the leaf litter (litterfall). This research evaluated the importance of forest type on the Total Hg (THg) flux in litterfall and on THg accumulation in organic soil horizons. Eighteen research sites were sampled throughout Vermont, USA. Mercury concentration was measured in senescing leaves of dominant tree species (16 species in total) in three forest types (low-elevation coniferous, mixed, and deciduous/Northern Hardwood forest). Leaf traps were used to measure the litterfall flux. Upper soil horizons were sampled and analyzed for mercury and carbon. Mercury concentration in senescing leaves varied significantly between tree species. Some hardwood species had higher THg concentration in leaves than coniferous species. Striped maple (Acer pensylvanicum) had significantly higher THg concentration than any other species. Total Hg concentration was negatively correlated with leaf height on the tree. Leaf surface-to-weight ratio was positively correlated with THg. The calculated THg flux in litterfall varied from 12 to 28 ug/m2/yr; there was no significant difference between forest types. Results showed an unexpectedly high THg concentration in understory trees. The assumption that needles have greater THg concentration than leaves needs to be revisited; forest structure needs to be taken into account. Total Hg concentration and THg to carbon ratio were consistent within soil horizons but differed among horizons. Similar to other studies, THg concentration was lower in the Oi horizon (litter layer) and peaked in the Oe horizon (fermentation layer) before declining in the humified Oa and/or A horizons. Mineral soil (A horizons) tended to have

  6. Bioaccumulation of cadmium by spring barley (Hordeum vulgare L. and its effect on selected physiological and morphological parameters

    Miriama Kopernická

    2016-01-01

    Full Text Available Heavy metals and other toxic elements in the environment, mainly located in soil and groundwater, have a significant effect on plant and its productivity that has a huge attention in recent years. Accumulation of heavy metals in soil cause toxicity to plants, and contaminate the food chain. The industrial areas, as well as developing countries have been contaminated with high concentration of heavy metals. Main sources of contamination are mining and other industrial processes, as well as military and or lanfills, sludge dumps or waste disposal sites. The heavy metals are very dangerous to environment and pose serious danger to public health by entering throught the food chain or into drinking water. Phytoextraction is one way how to remove the contaminants from soil by plants. Phytoextraction of heavy metals is a technology that has been studied for several years. It is more ecological and cheaper way how to clean our environment.Several plant species are known becauce they hyperaccumulate a high contents of metals from the soil. The accumulators are mainly herbaceous species, crops and nowadays angiosperm trees with a high growth such as poplars or willows. We have focused on the determination of some morphological (lenght and weight of roots and biomass and physiological (contents of dry mass and number of lief stomata characteristics and the determination of the bioaccumulation factor and the translocation factor of cadmium by spring barley (Hordeum vulgare L.. Imprints of leaves were evaluated using an optical microscope Axiostar Plus, Carl Zeiss, lens CP Achromat 40x/0.65, eyepiece PI 10x / 18, Canon Utilities Software Zoom Browser EX 4.6 and hardware Acer Travel Mate 4600, Canon Power Shot A95. The density of stomata was evaluated on an area of 1 mm2. Samples of the dried plants (leaves and roots were mineralized by acid digestion using microwave digestion device MARS X - press 5. The end of determination to obtain the cadmium content was

  7. Disturbance severity and net primary production resilience of a Great Lakes forest ecosystem

    Goodrich-Stuart, E. J.; Fahey, R.; De La Cruz, A.; Gough, C. M.

    2013-12-01

    nitrogen resources, appear to maintain NPP up to the disturbance severity threshold. Our results suggest that both canopy and subcanopy trees reacted rapidly to compensate for canopy tree mortality, but at higher disturbance severities, subcanopy trees provided an important buffer in support of NPP resilience. Our data also suggests a larger increase in the growth rate of red maples (Acer rubrum) following disturbance than subcanopy red oak (Quercus rubra) and white pine (Pinus strobus), as well as a greater contribution to overall plot-level production in more severely disturbed plots. These findings demonstrate that some forests can tolerate substantial disturbance without a reduction in NPP, suggesting that the relationship between disturbance severity and declining production may be non-linear. This result has important implications for the region's C cycle, suggesting that moderate disturbances may not cause a decline in forest C sequestration but may actually stimulate new growth to maintain NPP.

  8. Seasonal and vertical changes in leaf angle distribution for selected deciduous broadleaf tree species common to Europe

    Raabe, Kairi; Pisek, Jan; Sonnentag, Oliver; Annuk, Kalju

    2014-05-01

    Leaf inclination angle distribution is a key parameter in determining the transmission and reflection of radiation by vegetation canopies. It has been previously observed that leaf inclination angle might change gradually from more vertical in the upper canopy and in high light habitats to more horizontal in the lower canopy and in low light habitats [1]. Despite its importance, relatively few measurements on actual leaf angle distributions have been reported for different tree species. Even smaller number of studies have dealt with the possible seasonal changes in leaf angle distribution [2]. In this study the variation of leaf inclination angle distributions was examined both temporally throughout the growing season and vertically at different heights of trees. We report on leaf inclination angle distributions for five deciduous broadleaf species found commonly in several parts of Europe: grey alder (Alnus incana), Silver birch (Betula pendula Roth), chestnut (Castanea), Norway maple (Acer platanoides), and aspen (Populus tremula). The angles were measured using the leveled camera method [3], with the data collected at several separate heights and four times during the period of May-September 2013. The results generally indicate the greatest change in leaf inclination angles for spring, with the changes usually being the most pronounced at the top of the canopy. It should also be noted, however, that whereas the temporal variation proved to be rather consistent for different species, the vertical variation differed more between species. The leveled camera method was additionally tested in terms of sensitivity to different users. Ten people were asked to measure the leaf angles for four different species. The results indicate the method is quite robust in providing coinciding distributions irrespective of the user and level of previous experience with the method. However, certain caution must be exercised when measuring long narrow leaves. References [1] G.G. Mc

  9. Carbon and water exchange of a younger, drier deciduous forest compared to the long-term study site at Harvard Forest, Massachusetts

    Hadley, J. L.; Kuzeja, P. S.

    2004-05-01

    We measured carbon and water exchange by the eddy covariance method at a younger, drier deciduous forest and compared it to the well-known Harvard Forest deciduous site during two growing seasons (2002 and 2003) and an intervening dormant season. Forests at both sites are dominated by red oak (Quercus rubra) and red maple (Acer rubrum), but the younger forest is situated near a hilltop, as opposed to the long-term Harvard Forest site, which is in a lowland area within 100 m of a stream and about 200 m from a bog. The younger forest had a maximum tree age of about 44 years within 200 m of the eddy flux tower (owing to an intense fire in the autumn of 1957); this compares to maximum tree ages of 65 to 90 years, depending on exact location, near the long-term site. The younger, drier forest stored about 1.7 Mg C/ha from May 2002 through April 2003. We estimate that this was about 30% less than annual storage in the older, moister forest at the long-term site, but as the 12-month periods on which this comparison is based are not completely overlapping for the two sites, this comparison may change slightly. Light-saturated net ecosystem carbon uptake of both sites was about 22 μ mol m-2 s-1 in June 2002, but by August the value for the drier site was only about 20 μ mol m-2 s-1 compared to about 24 μ mol m-2 s-1 for the long-term site, suggesting that water availability may have become a limiting factor for photosynthesis in the drier forest. At the younger site in 2003 compared to 2002, we estimated less C storage in May and June but more C storage in July, August and September, with an overall increase in growing season C storage of about 0.4 Mg/ha. Lower early-growing season in carbon storage in 2003 versus 2002 was associated with slightly lower net ecosystem carbon uptake at all light levels in June 2003 compared to a year earlier. Cloudy and cool weather in May and early June 2003 reduced C uptake directly by reducing light available for photosynthesis, and

  10. Cost-effectiveness analysis of neonatal hearing screening program in china: should universal screening be prioritized?

    Huang Li-Hui

    2012-04-01

    Full Text Available Abstract Background Neonatal hearing screening (NHS has been routinely offered as a vital component of early childhood care in developed countries, whereas such a screening program is still at the pilot or preliminary stage as regards its nationwide implementation in developing countries. To provide significant evidence for health policy making in China, this study aims to determine the cost-effectiveness of NHS program implementation in case of eight provinces of China. Methods A cost-effectiveness model was conducted and all neonates annually born from 2007 to 2009 in eight provinces of China were simulated in this model. The model parameters were estimated from the established databases in the general hospitals or maternal and child health hospitals of these eight provinces, supplemented from the published literature. The model estimated changes in program implementation costs, disability-adjusted life years (DALYs, average cost-effectiveness ratio (ACER, and incremental cost-effectiveness ratio (ICER for universal screening compared to targeted screening in eight provinces. Results and discussion A multivariate sensitivity analysis was performed to determine uncertainty in health effect estimates and cost-effectiveness ratios using a probabilistic modeling technique. Targeted strategy trended to be cost-effective in Guangxi, Jiangxi, Henan, Guangdong, Zhejiang, Hebei, Shandong, and Beijing from the level of 9%, 9%, 8%, 4%, 3%, 7%, 5%, and 2%, respectively; while universal strategy trended to be cost-effective in those provinces from the level of 70%, 70%, 48%, 10%, 8%, 28%, 15%, 4%, respectively. This study showed although there was a huge disparity in the implementation of the NHS program in the surveyed provinces, both universal strategy and targeted strategy showed cost-effectiveness in those relatively developed provinces, while neither of the screening strategy showed cost-effectiveness in those relatively developing provinces. This

  11. Hypersensitivity to common tree pollens in New York City patients.

    Lin, Robert Y; Clauss, Allison E; Bennett, Edward S

    2002-01-01

    Testing for tree pollen hypersensitivity typically requires the use of several tree pollens. Identifying patterns of cross-sensitivity to tree pollens could reduce the number of trees used for testing. The goal of this study was to relate reported tree pollen levels to hypersensitivity patterns. Three hundred seventy-one allergy patients were tested serologically for hypersensitivity toward prevalent tree pollens in the surrounding New York area over the years 1993-2000. Specific tree pollens that were examined included oak (Quercus alba), birch (Betula verrucosa), beech (Fagus grandifolia), poplar (Populus deltoides), maple (Acer negundo), ash (Fraxinus americana), hickory (Carya pecan), and elm (Ulmus americana). Statistical analysis of the levels of hypersensitivity was performed to identify correlations and grouping factors. Pollen levels, obtained from published annual pollen and spore reports, were characterized and related to the prevalence of hypersensitivity for the various trees. The highest prevalence of hypersensitivity (score > or = class 1) was for oak (34.3%), birch (32.9%), and maple (32.8%) tree pollens. Lower prevalences were observed for beech (29.6%), hickory (27.1%), ash (26%), elm (24.6%), and poplar (20.6%) trees. Significant correlations were observed between oak, birch, and beech radioallergosorbent test scores. Factor analysis identified two independent pollen groups with oak, birch, and beech consisting of one group and the other five tree pollens constituting the other group. Peak pollen counts clearly were highest for oak, birch, and maple trees. The peak pollen counts corresponded roughly to seropositivity prevalences for the tree pollens. When elm, poplar, and beech test scores were not used to identify patients who were allergic to tree pollens, only 1 of 106 patients with any positive tree radioallergosorbent test score was missed. It is concluded that in the New York City area, hypersensitivity to tree pollens most often is

  12. Soil Warming Alters the Nitrogen Cycle: Ecosystem Implications and Feedbacks to the Climate System

    Butler, S. M.; Melillo, J. M.; Johnson, J. E.; Mohan, J. E.; Steudler, P. A.; Bowles, F. P.

    2008-12-01

    shown that red maples (Acer rubrum), when grown with high levels of nitrate, have a greater ability to produce this enzyme than many other species common to the region's forests. We have also observed that red maple seedlings and saplings show a higher growth response to soil warming than juvenile plants of other species. Our working hypothesis is that some of this response is linked to the capacity of red maple to use the nitrate produced in the warmed soils. In the long term, warming could lead to red maples becoming a more dominant tree in the forests of southern New England.

  13. Comparing riparian forest processes on large rivers to inform floodplain management and restoration

    Stella, J. C.; Piegay, H.; Gruel, C.; Riddle, J.; Raepple, B.

    2014-12-01

    by Acer negundo (box elder), which is non-native and invasive in Europe, suggesting similar processes of colonization and propagation in both systems. Overall, the Sacramento can serve as a predictive reference system for the Rhône, where significant restoration efforts are undeway to improve riparian structure and function in diverted river reaches.

  14. Plant and Soil Emissions of Amines and Amino Acids: A Source of Secondary Aerosol Precursors

    Jackson, M. L.; Doskey, P. V.; Pypker, T. G.

    2011-12-01

    Ammonia (NH3) is the most abundant alkaline gas in the atmosphere and forms secondary aerosol by neutralizing sulfuric and nitric acids that are released during combustion of fossil fuels. Ammonia is primarily emitted by cropping and livestock operations. However, C2 and C3 amines (pKb 3.3-3.4), which are stronger bases than NH3 (pKb 4.7) have been observed in nuclei mode aerosol that is the precursor to secondary aerosol. Mixtures of amines and amino acids have been identified in diverse environments in aerosol, fog water, cloud water, the soluble fraction of precipitation, and in dew. Glycine (pKb 4.2), serine (pKb 4.8) and alanine (pKb 3.7 and 4.1 for the D and L forms, respectively) are typically the most abundant species. The only reported values of gas-phase glycine, serine and alanine were in marine air and ranged from 6-14 pptv. The origin of atmospheric amines and amino acids has not been fully identified, although sources are likely similar to NH3. Nitrate assimilation in plants forms glycine, serine, and L-alanine, while D-alanine is present in bacterial cell walls. Glycine is converted to serine during C3 plant photorespiration, producing CO2 and NH3. Bacteria metabolize glycine and alanine to methylamine and ethylamine via decarboxylation. Likely sources of amino acids are plants and bacteria, thus concentrations near continental sources are likely greater than those measured in marine air. The overall goal of the research is to examine seasonal variations and relationships between the exchange of CO2, NH3, amines, and amino acids with a corn/soybean rotation in the Midwest Corn Belt. The study presents gaseous profiles of organic amine compounds from various species of vegetation using a mist chamber trapping technique and analysis of the derivatized species by high pressure liquid chromatography with fluorescence detection. Amino acid and amine profiles were obtained for red oak (Quercus rubra), sugar maple (Acer saccharinum), white pine (Pinus

  15. Oak Forest Responses to Episodic-Seasonal-Drought, Chronic Multi-year Precipitation Change and Acute Drought Manipulations in a Region With Deep Soils and High Precipitation

    Hanson, Paul J.; Wullschleger, Stan D.; Todd, Donald E.; Auge, Robert M.; Froberg, Mats; Johnson, Dale W.

    2010-05-01

    Implications of episodic-seasonal drought (extremely dry late summers), chronic multi-year precipitation manipulations (±33 percent over 12 years) and acute drought (-100 percent over 3 years) were evaluated for the response of vegetation and biogeochemical cycles for an upland-oak forest. The Quercus-Acer forest is located in eastern Tennessee on deep acidic soils with mean annual temperatures of 14.2 °C and abundant precipitation (1352 mm y-1). The multi-year observations and chronic manipulations were conducted from 1993 through 2005 using understory throughfall collection troughs and redistribution gutters and pipes. Acute manipulations of dominant canopy trees (Quercus prinus; Liriodendron tulipifera) were conducted from 2003 through 2005 using full understory tents. Regional and severe late-summer droughts were produced reduced stand water use and photosynthetic carbon gain as expected. Likewise, seedlings and saplings exhibited reduced survival and cumulative growth reductions. Conversely, multi-year chronic increases or decreases in precipitation and associated soil water deficits did not reduce large tree basal area growth for the tree species present. The resilience of canopy trees to chronic-change was the result of a disconnect between carbon allocation to tree growth (an early-season phenomenon) and late-season drought occurrence. Acute precipitation exclusion from the largest canopy trees also produced limited physiological responses and minimal cumulative growth reductions. Lateral root water sources were removed through trenching and could not explain the lack of response to extreme soil drying. Therefore, deep rooting the primary mechanism for large-tree resilience to severe drought. Extensive trench-based assessments of rooting depth suggested that ‘deep' water supplies were being obtained from limited numbers of deep fine roots. Observations of carbon stocks in organic horizons demonstrated accumulation with precipitation reductions and

  16. Responses of hybrid poplar clones and red maple seedlings to ambient O3 under differing light within a mixed hardwood forest

    The responses of ramets of hybrid poplar (Populus spp.) (HP) clones NE388 and NE359, and seedlings of red maple (Acer rubrum, L.) to ambient ozone (O3) were studied during May-September of 2000 and 2001 under natural forest conditions and differing natural sunlight exposures (sun, partial shade and full shade). Ambient O3 concentrations at the study site reached hourly peaks of 109 and 98 ppb in 2000 and 2001, respectively. Monthly 12-h average O3 concentrations ranged from 32.3 to 52.9 ppb. Weekly 12-h average photosynthetically active radiation (PAR) within the sun, partial shade and full shade plots ranged from 200 to 750, 50 to 180, and 25 to 75 μmol m-2 s-1, respectively. Ambient O3 exposure induced visible foliar symptoms on HP NE388 and NE359 in both growing seasons, with more severe injury observed on NE388 than on NE359. Slight foliar symptoms were observed on red maple seedlings during the 2001growing season. Percentage of total leaf area affected (%LAA) was positively correlated with cumulative O3 exposures. More severe foliar injury was observed on plants grown within the full shade and partial shade plots than those observed on plants grown within the sun plot. Lower light availability within the partial shade and full shade plots significantly decreased net photosynthetic rate (Pn) and stomatal conductance (gwv). The reductions in Pn were greater than reductions in gwv, which resulted in greater O3 uptake per unit Pn in plants grown within the partial shade and full shade plots. Greater O3 uptake per unit Pn was consistently associated with more severe visible foliar injury in all species and/or clones regardless of differences in shade tolerance. These studies suggest that plant physiological responses to O3 exposure are likely complicated due to multiple factors under natural forest conditions. - Under natural forest conditions and ambient O3 exposures, available light plays a significant role in determining O3 uptake and resulting physiological

  17. Litter Species Composition and Topographic Effects on Fuels and Modeled Fire Behavior in an Oak-Hickory Forest in the Eastern USA.

    Dickinson, Matthew B; Hutchinson, Todd F; Dietenberger, Mark; Matt, Frederick; Peters, Matthew P

    2016-01-01

    Mesophytic species (esp. Acer rubrum) are increasingly replacing oaks (Quercus spp.) in fire-suppressed, deciduous oak-hickory forests of the eastern US. A pivotal hypothesis is that fuel beds derived from mesophytic litter are less likely than beds derived from oak litter to carry a fire and, if they do, are more likely to burn at lower intensities. Species effects, however, are confounded by topographic gradients that affect overstory composition and fuel bed decomposition. To examine the separate and combined effects of litter species composition and topography on surface fuel beds, we conducted a common garden experiment in oak-hickory forests of the Ohio Hills. Each common garden included beds composed of mostly oak and mostly maple litter, representative of oak- and maple-dominated stands, respectively, and a mixture of the two. Beds were replenished each fall for four years. Common gardens (N = 16) were established at four topographic positions (ridges, benches on south- and northeast-facing slopes, and stream terraces) at each of four sites. Litter source and topographic position had largely independent effects on fuel beds and modeled fire dynamics after four years of development. Loading (kg m-2) of the upper litter layer (L), the layer that primarily supports flaming spread, was least in more mesic landscape positions and for maple beds, implying greater decomposition rates for those situations. Bulk density in the L layer (kg m-3) was least for oak beds which, along with higher loading, would promote fire spread and fireline intensity. Loading and bulk density of the combined fermentation and humic (FH) layers were least on stream terrace positions but were not related to species. Litter- and FH-layer moistures during a 5-day dry-down period after a rain event were affected by time and topographic effects while litter source effects were not evident. Characteristics of flaming combustion determined with a cone calorimeter pointed to greater fireline

  18. Soil organic carbon sequestration as affected by afforestation: the Darab Kola forest (north of Iran) case study.

    Kooch, Yahya; Hosseini, Seyed Mohsen; Zaccone, Claudio; Jalilvand, Hamid; Hojjati, Seyed Mohammad

    2012-09-01

    Following the ratification of the Kyoto Protocol, afforestation of formerly arable lands and/or degraded areas has been acknowledged as a land-use change contributing to the mitigation of increasing atmospheric CO(2) concentration in the atmosphere. In the present work, we study the soil organic carbon sequestration (SOCS) in 21 year old stands of maple (Acer velutinum Bioss.), oak (Quercus castaneifolia C.A. Mey.), and red pine (Pinus brutia Ten.) in the Darab Kola region, north of Iran. Soil samples were collected at four different depths (0-10, 10-20, 20-30, and 30-40 cm), and characterized with respect to bulk density, water content, electrical conductivity, pH, texture, lime content, total organic C, total N, and earthworm density and biomass. Data showed that afforested stands significantly affected soil characteristics, also raising SOCS phenomena, with values of 163.3, 120.6, and 102.1 Mg C ha(-1) for red pine, oak and maple stands, respectively, vs. 83.0 Mg C ha(-1) for the control region. Even if the dynamics of organic matter (OM) in soil is very complex and affected by several pedo-climatic factors, a stepwise regression method indicates that SOCS values in the studied area could be predicted using the following parameters, i.e., sand, clay, lime, and total N contents, and C/N ratio. In particular, although the chemical and physical stabilization capacity of organic C by soil is believed to be mainly governed by clay content, regression analysis showed a positive correlation between SOCS and sand (R = 0.86(**)), whereas a negative correlation with clay (R = -0.77(**)) was observed, thus suggesting that most of this organic C occurs as particulate OM instead of mineral-associated OM. Although the proposed models do not take into account possible changes due to natural and anthropogenic processes, they represent a simple way that could be used to evaluate and/or monitor the potential of each forest plantation in immobilizing organic C in soil (thus

  19. Study of overall arrangement for construction of China's industrial system of non-wood forest crops Ⅰ: woody edible oil%中国现代经济林产业体系建设布局研究Ⅰ——木本食用油料篇

    何方

    2011-01-01

    现代经济林是我国社会主义现代建设中不可缺少和不可替代的.为科学发展与转变发展方式,必须进行产业布局的研究.有关现代经济林的产业布局,笔者提出了指导思想与指导原则,并将现代经济林分为食用油料、工业用油、油脂类干果、淀粉类干果、香调料、饮料等7大类,约含60余种产业,基本涵盖了全国主要名特优产品.并具体分述了油茶、油橄榄、椰子、文冠果、元宝枫、仁用杏及毛株的适用区域、栽培方法与产业布局.%Construction of the industrial system of non-wood forest crops plays an indispensible role in China' s socialist modernization.An overall arrangement must be made in order to meet the requirements for scientific development.Guiding ideology and principles were put forward, followed by a detailed research report of why and how to categorize the main non-wood forest crops into crops that mainly produce edible oils, industrial oils, fat-type dry fruit and nuts,starch-type dry fruit and nuts, spice and condiment, forest-based beverage raw materials and chemically industrial raw materials.Approximately sixty industrial sectors were involved to cover the production of all the famous and quality non-wood forest products in China.Production base areas of all these products were laid out.Growing region,cultivation methods and overall arrangement of Camellia oleifera , Olea euporaea , Xaruthoceras sobifolia , Cocos mucifara ,Acer truncatum, Armeniaca vulgaris and Carnus walteri were also discussed.

  20. Plant-Arthropod Associations from the Lower Miocene of the Most Basin in Northern Bohemia(Czech Republic):A Preliminary Report

    Jakub PROKOP; Torsten WAPPLER; Stanislav KNOR; Zlatko KVA(C)EK

    2010-01-01

    Terrestrial plants and insects currently account for the majority of the Earth's biodiversity,and approximately half of insect species are herbivores.Thus,insects and plants share ancient associations that date back more than 400 Myr.However,investigations of their past interactions are at the preliminary stages in Western Europe.Herein,we present the first results of our study of various feeding damage based on a dataset of nearly 3500 examined plant specimens from the Lower Miocene of the Lagerstatte Bilina Mine in the Most Basin,Czech Republic.This site provides a unique view of the Neogcue freshwater ecosystems.It has long been studied by scientists working in different branches of sedimentology,paleobotany,and paleozoology.The fossils are preserved in three characteristic horizons overlaying the coal seam(Clayey Superseam Horizon,Delta Sandy Horizon,and Lake Clayey Horizon),reflecting paleoenvironmental changes in a short time period of development.The trace fossils are classified as functional feeding groups or"guilds",without searching for a direct cause or a recent analog host relation.Approximately 23% of specimens of dicotyledonous plant leaves were found to be damaged and associated with some leaf"morphotypes".Deciduous plant-host taxa,and those with a chartaceons texture typical of riparian habitats,were frequently damaged,such as Populus,recorded with two species Populus zaddachii and Populus populina(57.9% and 31% herbivory levels,respectively),followed by Acer,Alnus,and Carya,averaging almost 30% of damaged leaves/leaflets.There has been evidence of 60 damage types(DT)representing all functional feeding groups recorded at the Bilina Mine,including 12 types of leaf mines and 16 galltype DT.In total,Lower Miocene of the Lagerstatte Bilina Mine exhibits a high level of external foliage feeding types(23.7%),and a low level of more specialized DT,such as galls(4.3%)and leaf mines(<1%).A broader comparison based on DT of the main sedimentary environments