Tree Species Identity Shapes Earthworm Communities

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Stephanie Schelfhout

2017-03-01

Full Text Available Earthworms are key organisms in forest ecosystems because they incorporate organic material into the soil and affect the activity of other soil organisms. Here, we investigated how tree species affect earthworm communities via litter and soil characteristics. In a 36-year old common garden experiment, replicated six times over Denmark, six tree species were planted in blocks: sycamore maple (Acer pseudoplatanus, beech (Fagus sylvatica, ash (Fraxinus excelsior, Norway spruce (Picea abies, pedunculate oak (Quercus robur and lime (Tilia cordata. We studied the chemical characteristics of soil and foliar litter, and determined the forest floor turnover rate and the density and biomass of the earthworm species occurring in the stands. Tree species significantly affected earthworm communities via leaf litter and/or soil characteristics. Anecic earthworms were abundant under Fraxinus, Acer and Tilia, which is related to calcium-rich litter and low soil acidification. Epigeic earthworms were indifferent to calcium content in leaf litter and were shown to be mainly related to soil moisture content and litter C:P ratios. Almost no earthworms were found in Picea stands, likely because of the combined effects of recalcitrant litter, low pH and low soil moisture content.

Factors affecting the survival of ash (Fraxinus spp.) trees infested by emerald ash borer (Agrilus planipennis)

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Kathleen S. Knight; John P. Brown; Robert P. Long

2013-01-01

Emerald ash borer (Agrilus planipennis) (EAB), an Asian woodboring beetle accidentally introduced in North America, has killed millions of ash (Fraxinus spp.) trees and is spreading rapidly. This study examined the effects of tree- and site-level factors on the mortality of ash trees in stands infested by EAB in OH, USA. Our data...

Evidence of Ash Tree (Fraxinus spp.) Specific Associations with Soil Bacterial Community Structure and Functional Capacity

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Michael P. Ricketts; Charles E. Flower; Kathleen S. Knight; Miquel A. Gonzalez-Meler

2018-01-01

The spread of the invasive emerald ash borer (EAB) across North America has had enormous impacts on temperate forest ecosystems. The selective removal of ash trees (Fraxinus spp.) has resulted in abnormally large inputs of coarse woody debris and altered forest tree community composition, ultimately affecting a variety of ecosystem processes. The...

Soil respiration and rates of soil carbon turnover differ among six common European tree species

DEFF Research Database (Denmark)

Vesterdal, Lars; Elberling, Bo; Christiansen, Jesper Riis

2012-01-01

replicated at six sites in Denmark. The studied tree species were the broadleaves beech (Fagus sylvatica L.), pedunculate oak (Quercus robur L.), lime (Tilia cordata L.), sycamore maple (Acer pseudoplatanus L.) and ash (Fraxinus excelsior L.) and the conifer Norway spruce (Picea abies (L.) Karst.). Rates....... Soil respiration differed significantly among several species and increased in the order beechmaple... moisture. Carbon turnover rates based on the ratio between R h and C stock were significantly higher in ash than in all other species except maple, and maple also had higher C turnover than spruce. A similar influence of tree species on C turnover was indicated by the litterfall C to forest floor C ratio...

Urban tree effects on soil organic carbon.

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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.

Seven-Year Evaluation of Insecticide Tools for Emerald Ash Borer in Fraxinus pennsylvanica (Lamiales: Oleaceae) Trees.

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Bick, Emily N; Forbes, Nora J; Haugen, Christopher; Jones, Grant; Bernick, Shawn; Miller, Fredric

2018-04-02

Emerald ash borer (EAB), Agrilus planipennis (Fairmaire; Coleoptera: Buprestidae), is decimating ash trees (Fraxinus spp.) in North America. Combatting EAB includes the use of insecticides; however, reported insecticide efficacy varies among published studies. This study assessed the effects of season of application, insecticide active ingredient, and insecticide application rate on green ash (Fraxinus pennsylvanica Marsh.) (Lamiales: Oleaceae) canopy decline caused by EAB over a 5- to 7-yr interval. Data suggested that spring treatments were generally more effective in reducing canopy decline than fall treatments, but this difference was not statistically significant. Lowest rates of decline (<5% over 5 yr) were observed in trees treated with imidacloprid injected annually in the soil during spring (at the higher of two tested application rates; 1.12 g/cm diameter at 1.3 m height) and emamectin benzoate injected biennially into the stem. All tested insecticides (dinotefuran, emamectin benzoate, and imidacloprid) under all tested conditions significantly reduced the rate of increase of dieback.

Tree species effect on the redistribution of soil metals

International Nuclear Information System (INIS)

Mertens, Jan; Van Nevel, Lotte; De Schrijver, An; Piesschaert, Frederic; Oosterbaan, Anne; Tack, Filip M.G.; Verheyen, Kris

2007-01-01

Phytostabilization of metals using trees is often promoted although the influence of different tree species on the mobilization of metals is not yet clear. Soil and biomass were sampled 33 years after planting four tree species (Quercus robur, Fraxinus excelsior, Acer pseudoplatanus, Populus 'Robusta') in a plot experiment on dredged sediment. Poplar took up high amounts of Cd and Zn and this was associated with increased Cd and Zn concentrations in the upper soil layer. The other species contained normal concentrations of Cd, Cu, Cr, Pb and Zn in their tissues. Oak acidified the soil more than the other species and caused a decrease in the concentration of metals in the upper soil layer. The pH under poplar was lower than expected and associated with high carbon concentrations in the top soil. This might be assigned to retardation of the litter decomposition due to elevated Cd and Zn concentrations in the litter. - Trees (33-year-old) growing on polluted dredged sediment have influenced the metal concentration in the upper soil layer and there was a significant tree species effect

A novel dendrochronological approach reveals drivers of carbon sequestration in tree species of riparian forests across spatiotemporal scales.

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Rieger, Isaak; Kowarik, Ingo; Cherubini, Paolo; Cierjacks, Arne

2017-01-01

Aboveground carbon (C) sequestration in trees is important in global C dynamics, but reliable techniques for its modeling in highly productive and heterogeneous ecosystems are limited. We applied an extended dendrochronological approach to disentangle the functioning of drivers from the atmosphere (temperature, precipitation), the lithosphere (sedimentation rate), the hydrosphere (groundwater table, river water level fluctuation), the biosphere (tree characteristics), and the anthroposphere (dike construction). Carbon sequestration in aboveground biomass of riparian Quercus robur L. and Fraxinus excelsior L. was modeled (1) over time using boosted regression tree analysis (BRT) on cross-datable trees characterized by equal annual growth ring patterns and (2) across space using a subsequent classification and regression tree analysis (CART) on cross-datable and not cross-datable trees. While C sequestration of cross-datable Q. robur responded to precipitation and temperature, cross-datable F. excelsior also responded to a low Danube river water level. However, CART revealed that C sequestration over time is governed by tree height and parameters that vary over space (magnitude of fluctuation in the groundwater table, vertical distance to mean river water level, and longitudinal distance to upstream end of the study area). Thus, a uniform response to climatic drivers of aboveground C sequestration in Q. robur was only detectable in trees of an intermediate height class and in taller trees (>21.8m) on sites where the groundwater table fluctuated little (≤0.9m). The detection of climatic drivers and the river water level in F. excelsior depended on sites at lower altitudes above the mean river water level (≤2.7m) and along a less dynamic downstream section of the study area. Our approach indicates unexploited opportunities of understanding the interplay of different environmental drivers in aboveground C sequestration. Results may support species-specific and

Canopy treatment influences growth of replacement tree species in Fraxinus nigra forests threatened by the emerald ash borer in Minnesota, USA

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Christopher E. Looney; Anthony W. D' Amato; Brian J. Palik; Robert A. Slesak

2017-01-01

Fraxinus nigra Marsh. (black ash), a dominant tree species of wetland forests in northern Minnesota, USA, is imperiled by the invasive insect emerald ash borer (EAB; Agrilus planipennis Fairmaire, 1888). Regeneration of associated tree species is generally low in F. nigra forests and could be impacted...

Morphological variability of Fraxinus angustifolia Vahl in the north-western Balkans

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Kristjan Jarni

2011-08-01

Full Text Available Fraxinus angustifolia Vahl is a species native in the north-western Balkans, where it has a divided range. Most of its range is located in flood-prone riparian sites in the Pannonian plain but the species is also found on humid sites along some rivers in the Submediterranean region. We analysed morphologic variation within and between five populations (14 trees/population located in the Subpannonian and Submediterranean region of Slovenia. Thirty two characters were assessed on ca. 80 leaves from each tree which were divided depending on exposure to sunlight (sun and shade leaves, and 8 traits on each fruit (ca. 50 fruits/tree. A hierarchically designed experiment using analysis of variance confirmed the significant contribution of all the analysed hierarchical levels of variation to the total variation. The results show that the differences between the trees in a single population are the greatest factor of variability of leaves, followed by differences between populations and differences which are the result of variation in exposure to sunlight. Leaves in shade positions are typically larger than those in sunny positions, and they have broader and shorter-pointed leaflets; in this feature they are very similar to the leaves of F. excelsior. Stepwise discriminant analysis showed that the traits which refer to the leaflet number and length are the best differentiating traits between individual populations. The Submediterranean population Dragonja stands out with the smallest leaves and the population Lijak from the same region is the most similar to Dragonja for most morphological traits. In general, phenotypic differences between the Subpannonian and the Submediterranean populations of F. angustifolia are minor and indistinct. Based on the differences ascertained by the study, we can only confirm the presence of F. angustifolia subsp. oxycarpa (Bieb. ex Willd. Franco et Rocha Alfonso in this part of its natural range.

Cross amplification of 15 SSR markers in the genus Fraxinus

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Andrea G. Noakes; Teodora Best; Margaret E. Stanton; Jennifer Koch; Jeanne Romero-Severson

2014-01-01

Ash (Fraxinus, Oleaceae) species occur on most continents, within a wide range of forest tree communities. Emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), introduced into the U.S. from Asia in the late twentieth century, has caused widespread mortality, primarily in green ash, Fraxinus...

In vitro propagation of Fraxinus species

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J.W. Van Sambeek; J.E. Preece

2007-01-01

The genus Fraxinus, a member of the Oleaceae family, includes over 65 ash species native to the temperate regions of the northern hemisphere (Miller, 1955). Several of the ash species are important forest trees noted for their tough, highly resistant to shock, straight grained wood as well as being excellent shade trees for parks and residential...

Friend or foe? Biological and ecological traits of the European ash dieback pathogen Hymenoscyphus fraxineus in its native environment

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Cleary, Michelle; Nguyen, Diem; Marčiulynienė, Diana; Berlin, Anna; Vasaitis, Rimvys; Stenlid, Jan

2016-02-01

Hymenoscyphus fraxineus, an introduced ascomycete fungus and primary causal agent of European ash dieback, was investigated on Fraxinus mandshurica trees in its native range in Primorye region of Far East Russia. This evidence is the first report of H. fraxineus on healthy, asymptomatic F. mandshurica trees. High-throughput sequencing revealed 49 distinct fungal taxa associated with leaves of F. mandshurica, 12 of which were identified to species level. Phyllosphere fungal assemblages were similar among sites despite being largely geographically distant. Many organisms comprising the foliar fungal community on F. mandshurica in Far East Russia have similarity to those reported inhabiting F. excelsior in Europe based on previous studies. However, Mycosphaerella sp., the most dominant species in this study and detected in nearly all samples, was associated only with F. mandshurica. Genetic diversity of H. fraxineus was significantly higher in the Far East Russian population than in Europe. In contrast to its aggressive behaviour on Fraxinus excelsior in Europe, H. fraxineus appears to be a benign associate of indigenous F. mandshurica that initially induces quiescent and asymptomatic infections in healthy trees prior to active host colonization normally associated with modification of host tissue during senescence.

Physiological and foliar symptom response of Prunus serotina, Fraxinus americana and Acer rubrum canopy trees to ozone under differing site conditions

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M. Schaub; J.M. Skelly; J.W. Zhang; J.A. Ferdinand; J.E. Savage; R.E. Stevenson; D.D. Davis; K.C. Steiner

2005-01-01

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....

The Phylogeny and Biogeographic History of Ashes (Fraxinus, Oleaceae) Highlight the Roles of Migration and Vicariance in the Diversification of Temperate Trees

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Hinsinger, Damien Daniel; Basak, Jolly; Gaudeul, Myriam; Cruaud, Corinne; Bertolino, Paola; Frascaria-Lacoste, Nathalie; Bousquet, Jean

2013-01-01

The cosmopolitan genus Fraxinus, which comprises about 40 species of temperate trees and shrubs occupying various habitats in the Northern Hemisphere, represents a useful model to study speciation in long-lived angiosperms. We used nuclear external transcribed spacers (nETS), phantastica gene sequences, and two chloroplast loci (trnH-psbA and rpl32-trnL) in combination with previously published and newly obtained nITS sequences to produce a time-calibrated multi-locus phylogeny of the genus. We then inferred the biogeographic history and evolution of floral morphology. An early dispersal event could be inferred from North America to Asia during the Oligocene, leading to the diversification of the section Melioides sensus lato. Another intercontinental dispersal originating from the Eurasian section of Fraxinus could be dated from the Miocene and resulted in the speciation of F. nigra in North America. In addition, vicariance was inferred to account for the distribution of the other Old World species (sections Sciadanthus, Fraxinus and Ornus). Geographic speciation likely involving dispersal and vicariance could also be inferred from the phylogenetic grouping of geographically close taxa. Molecular dating suggested that the initial divergence of the taxonomical sections occurred during the middle and late Eocene and Oligocene periods, whereas diversification within sections occurred mostly during the late Oligocene and Miocene, which is consistent with the climate warming and accompanying large distributional changes observed during these periods. These various results underline the importance of dispersal and vicariance in promoting geographic speciation and diversification in Fraxinus. Similarities in life history, reproductive and demographic attributes as well as geographical distribution patterns suggest that many other temperate trees should exhibit similar speciation patterns. On the other hand, the observed parallel evolution and reversions in floral

Optimizing Conservation Strategies for a Threatened Tree Species: In Situ Conservation of White Ash (Fraxinus americana L. Genetic Diversity through Insecticide Treatment

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Charles E. Flower

2018-04-01

Full Text Available Forest resources face numerous threats that require costly management. Hence, there is an increasing need for data-informed strategies to guide conservation practices. The introduction of the emerald ash borer to North America has caused rapid declines in ash populations (Fraxinus spp. L.. Natural resource managers are faced with a choice of either allowing ash trees to die, risking forest degradation and reduced functional resilience, or investing in conserving trees to preserve ecosystem structure and standing genetic diversity. The information needed to guide these decisions is not always readily available. Therefore, to address this concern, we used eight microsatellites to genotype 352 white ash trees (Fraxinus americana L. across 17 populations in the Allegheny National Forest; a subset of individuals sampled are part of an insecticide treatment regimen. Genetic diversity (number of alleles and He was equivalent in treated and untreated trees, with little evidence of differentiation or inbreeding, suggesting current insecticidal treatment is conserving local, neutral genetic diversity. Using simulations, we demonstrated that best practice is treating more populations rather than more trees in fewer populations. Furthermore, through genetic screening, conservation practitioners can select highly diverse and unique populations to maximize diversity and reduce expenditures (by up to 21%. These findings will help practitioners develop cost-effective strategies to conserve genetic diversity.

Overstory treatment and planting season affect survival of replacement tree species in emerald ash borer threatened Fraxinus nigra forests in Minnesota, USA

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Christopher E. Looney; Anthony W. D' Amato; Brian J. Palik; Robert A. Slesak

2015-01-01

Fraxinus nigra Marsh. (black ash) wetland forests in northern Minnesota, USA, are threatened by the invasive insect, emerald ash borer (Agrilus planipennis Fairmaire (EAB)). A potential management option is promoting regeneration of tree species that are not EAB hosts to maintain ecosystem functions. Using an operational-scale...

The relationship between the emerald ash borer (Agrilus planipennis) and ash (Fraxinus spp.) tree decline: Using visual canopy condition assessments and leaf isotope measurements to assess pest damage

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Charles E. Flower; Kathleen S. Knight; Joanne Rebbeck; Miquel A. Gonzalez-Meler

2013-01-01

Ash trees (Fraxinus spp.) in North America are being severely impacted by the invasive emerald ash borer (Agrilus planipennis Fairmaire) which was inadvertently introduced to the US in the 1990s from Asia. The emerald ash borer (EAB) is a phloem boring beetle which relies exclusively on ash trees to complete its life cycle. Larvae...

Evaluation of reference genes for expression studies in ash (Fraxinus spp.)

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Loren Rivera-Vega; Praveen Mamidala; Jennifer L. Koch; Mary E. Mason; Omprakash. Mittapalli

2012-01-01

Ash (Fraxinus spp.) is a dominant tree species in North America, in both managed and natural landscapes. However, due to the rapid invasion by the emerald ash borer (Agrilus planipennis), an exotic invasive insect pest, millions of North American ash trees have been killed. Real-time quantitative polymerase chain reaction (RTq-PCR...

Biotic and Abiotic Drivers of Sap Flux in Mature Green Ash Trees (Fraxinus pennsylvanica) Experiencing Varying Levels of Emerald Ash Borer (Agrilus planipennis) Infestation

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Charles E. Flower; Douglas J. Lynch; Kathleen S. Knight; Miquel A.  Gonzalez-Meler

2018-01-01

While the relationship between abiotic drivers of sap flux are well established, the role of biotic disturbances on sap flux remain understudied. The invasion of the emerald ash borer (Agrilus planipennis Fairmaire, EAB) into North America in the 1990s represents a significant threat to ash trees (Fraxinus spp.), which are a...

How much does climate change threaten European forest tree species distributions?

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Dyderski, Marcin K; Paź, Sonia; Frelich, Lee E; Jagodziński, Andrzej M

2018-03-01

Although numerous species distribution models have been developed, most were based on insufficient distribution data or used older climate change scenarios. We aimed to quantify changes in projected ranges and threat level by the years 2061-2080, for 12 European forest tree species under three climate change scenarios. We combined tree distribution data from the Global Biodiversity Information Facility, EUFORGEN, and forest inventories, and we developed species distribution models using MaxEnt and 19 bioclimatic variables. Models were developed for three climate change scenarios-optimistic (RCP2.6), moderate (RCP4.5), and pessimistic (RPC8.5)-using three General Circulation Models, for the period 2061-2080. Our study revealed different responses of tree species to projected climate change. The species may be divided into three groups: "winners"-mostly late-successional species: Abies alba, Fagus sylvatica, Fraxinus excelsior, Quercus robur, and Quercus petraea; "losers"-mostly pioneer species: Betula pendula, Larix decidua, Picea abies, and Pinus sylvestris; and alien species-Pseudotsuga menziesii, Quercus rubra, and Robinia pseudoacacia, which may be also considered as "winners." Assuming limited migration, most of the species studied would face a significant decrease in suitable habitat area. The threat level was highest for species that currently have the northernmost distribution centers. Ecological consequences of the projected range contractions would be serious for both forest management and nature conservation. © 2017 John Wiley & Sons Ltd.

Fraxinus pollen as a source of environmental pollution

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María Fernández-González

2016-06-01

Full Text Available In Southern Europe there are but a few studies focused on the allergenic impact of ash (Fraxinus pollen as a result of its scarce distribution. In the city of Ourense this type of pollen represents 2% of the total atmospheric pollen recorded. The goal of this study is to determine the atmospheric concentrations of Fraxinus pollen and its allergen in Ourense’s atmosphere in 2015, and to assess their relationship with the main meteorological variables. The aim is to assess whether the pollen counts match the actual exposure conditions for allergen-sensitive patients. A Lanzoni VPPS-2000 volumetric sampler was used for pollen sampling, whereas a Burkard Cyclone sampler was used for allergen detection.The flowering period of Fraxinus was long, having a duration of 76 days between the third week of January and the rst week of April as consequence of the asynchronous flowering of the different species growing in the study area. The presence of the ash allergen in the atmosphere can be detected using the main olive tree allergen, Ole e 1. Our study indicates that the combination of pollen counts and allergen quanti cation should be contemplated to estimate the real exposure of sensitive people. In the case of Fraxinus pollen, there may be allergy risk periods before and after the occurrence of the highest pollen concentrations in the atmosphere as a result of special rain and humidity conditions during its flowering period.

Ozone air pollution effects on tree-ring growth,{delta}{sup 13}C, visible foliar injury and leaf gas exchange in three ozone-sensitive woody plant species

Energy Technology Data Exchange (ETDEWEB)

Novak, K. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland); Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Saurer, M. [Paul Scherrer Inst. Villigen (Switzerland); Fuhrer, J. [Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Skelly, J.M. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Plant Pathology; Krauchi, N.; Schaub, M. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland)

2007-07-15

Species specific plant responses to tropospheric ozone pollution depend on a range of morphological, biochemical and physiological characteristics as well as environmental factors. The effects of ambient tropospheric ozone on annual tree-ring growth, {delta}{sup 13} C in the rings, leaf gas exchange and ozone-induced visible foliar injury in three ozone-sensitive woody plant species in southern Switzerland were assessed during the 2001 and 2002 growing seasons. Seedlings of Populus nigra L., Viburnum lantana L. and Fraxinus excelsior L. were exposed to charcoal-filtered air and non-filtered air in open-top chambers, and to ambient air (AA) in open plots. The objective was to determine if a relationship exists between measurable ozone-induced effects at the leaf level and subsequent changes in annual tree-ring growth and {delta} {sup 13} C signatures. The visible foliar injury, early leaf senescence and premature leaf loss in all species was attributed to the ambient ozone exposures in the region. Ozone had pronounced negative effects on net photosynthesis and stomatal conductance in all species in 2002 and in V. lantana and F. excelsior in 2001. Water-use efficiency decreased and intercellular carbon dioxide concentrations increased in all species in response to ozone in 2002 only. The width and {delta}{sup 13} C of the 2001 and 2002 growth rings were measured for all species at the end of the 2002 growing season. Significant ozone-induced effects at the leaf level did not correspond to reduced tree-ring growth or increased {delta}{sup 13} C in all species, suggesting that the timing of ozone exposure and extent of leaf-level responses may be relevant in determining the sensitivity of tree productivity to ozone exposure. 48 refs., 4 tabs., 2 figs.

How fast will trees die? A transition matrix model of ash decline in forest stands infested by emerald ash borer

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Kathleen S. Knight; Robert P. Long; Joanne Rebbeck; Annemarie Smith; Kamal Gandhi; Daniel A. Herms

2008-01-01

We recorded Fraxinus spp. tree health and other forest stand characteristics for 68 plots in 21 EAB-infested forest stands in Michigan and Ohio in 2005 and 2007. Fraxinus spp. were a dominant component of these stands, with more than 900 ash trees (including Fraxinus americana, Fraxinus pennsylvanica, Fraxinus profunda...

Fraxinus: A Plant with Versatile Pharmacological and Biological Activities.

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Sarfraz, Iqra; Rasul, Azhar; Jabeen, Farhat; Younis, Tahira; Zahoor, Muhammad Kashif; Arshad, Muhammad; Ali, Muhammad

2017-01-01

Fraxinus , a member of the Oleaceae family, commonly known as ash tree is found in northeast Asia, north America, east and western France, China, northern areas of Pakistan, India, and Afghanistan. Chemical constituents of Fraxinus plant include various secoiridoids, phenylethanoids, flavonoids, coumarins, and lignans; therefore, it is considered as a plant with versatile biological and pharmacological activities. Its tremendous range of pharmacotherapeutic properties has been well documented including anticancer, anti-inflammatory, antioxidant, antimicrobial, and neuroprotective. In addition, its bioactive phytochemicals and secondary metabolites can be effectively used in cosmetic industry and as a competent antiaging agent. Fraxinus presents pharmacological effectiveness by targeting the novel targets in several pathological conditions, which provide a spacious therapeutic time window. Our aim is to update the scientific research community with recent endeavors with specifically highlighting the mechanism of action in different diseases. This potentially efficacious pharmacological drug candidate should be used for new drug discovery in future. This review suggests that this plant has extremely important medicinal utilization but further supporting studies and scientific experimentations are mandatory to determine its specific intracellular targets and site of action to completely figure out its pharmacological applications.

Evidence of Ash Tree (Fraxinus spp. Specific Associations with Soil Bacterial Community Structure and Functional Capacity

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Michael P. Ricketts

2018-04-01

Full Text Available The spread of the invasive emerald ash borer (EAB across North America has had enormous impacts on temperate forest ecosystems. The selective removal of ash trees (Fraxinus spp. has resulted in abnormally large inputs of coarse woody debris and altered forest tree community composition, ultimately affecting a variety of ecosystem processes. The goal of this study was to determine if the presence of ash trees influences soil bacterial communities and/or functions to better understand the impacts of EAB on forest successional dynamics and biogeochemical cycling. Using 16S rRNA amplicon sequencing of soil DNA collected from ash and non-ash plots in central Ohio during the early stages of EAB infestation, we found that bacterial communities in plots with ash differed from those without ash. These differences were largely driven by Acidobacteria, which had a greater relative abundance in non-ash plots. Functional genes required for sulfur cycling, phosphorus cycling, and carbohydrate metabolism (specifically those which breakdown complex sugars to glucose were estimated to be more abundant in non-ash plots, while nitrogen cycling gene abundance did not differ. This ash-soil microbiome association implies that EAB-induced ash decline may promote belowground successional shifts, altering carbon and nutrient cycling and changing soil properties beyond the effects of litter additions caused by ash mortality.

Interplay of growth rate and xylem plasticity for optimal coordination of carbon and hydraulic economies in Fraxinus ornus trees.

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Petit, Giai; Savi, Tadeja; Consolini, Martina; Anfodillo, Tommaso; Nardini, Andrea

2016-11-01

Efficient leaf water supply is fundamental for assimilation processes and tree growth. Renovating the architecture of the xylem transport system requires an increasing carbon investment while growing taller, and any deficiency of carbon availability may result in increasing hydraulic constraints to water flow. Therefore, plants need to coordinate carbon assimilation and biomass allocation to guarantee an efficient and safe long-distance transport system. We tested the hypothesis that reduced branch elongation rates together with carbon-saving adjustments of xylem anatomy hydraulically compensate for the reduction in biomass allocation to xylem. We measured leaf biomass, hydraulic and anatomical properties of wood segments along the main axis of branches in 10 slow growing (SG) and 10 fast growing (FG) Fraxinus ornus L. trees. Branches of SG trees had five times slower branch elongation rate (7 vs 35 cm year -1 ), and produced a higher leaf biomass (P trees in terms of leaf-specific conductivity (P > 0.05) and xylem safety (Ψ 50 ≈ -3.2 MPa). Slower elongation rate coupled with thinner annual rings and larger vessels allows the reduction of carbon costs associated with growth, while maintaining similar leaf-specific conductivity and xylem safety. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Post-planting treatments and shading effects in a Fraxinus angustifolia Vahl. silvopastoral system

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Giorgos Klossas

2013-05-01

Full Text Available Silvopastoral systems present difficulties in their management dueto their complexity. When trees are planted into grasslands, they need protection from livestock to prevent damage from trampling or browsing, especially during early years of establishment. One of the common post-planting protective treatments is the protection of individual trees with shelters. Trees also need protection from competition from herbaceous vegetation. The aim of present study was to evaluate the effects of using different types of tree shelters and of controlling competing herbaceous vegetation on the growth of planted young trees and, to assess the effects of heavy shadingon the herbage production and composition. The study was conducted in a Fraxinus angustifolia silvopastoral system of a 2 x 2.5 m spacing plantation in northern Greece. The effects of solid-walled (tubex and handmade by greenhouse nylon and wire mesh tree shelters as well as of herbicide application and mechanical removal of the competing herbaceous vegetation on tree height, height increment and the crown surface area of the trees were tested. The effects of artificial shading (80% on the production of the natural herbaceous vegetation were also investigated. All measurements were recorded three years after plantation. The use of solid wall tubex shelters resultedin higher tree height and higher crown surface area in comparison tothe other tested shelters. The solid wall Nylon shelters were more beneficial to the above growth parameters than the wire mesh ones. Both vegetation control treatments proved beneficial to all the growth parameters of Fraxinus angustifolia. The artificially applied heavy shading reduced herbage production by 54% compared to the control. The results indicated that post planting treatments in the Mediterranean droughty conditions are essential for the success of this tree species establishment. Furthermore, the later thinning of the dense spacing is important to maintain

Post-planting treatments and shading effects in a Fraxinus angustifolia Vahl. silvopastoral system

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Giorgos Klossas

2013-07-01

Full Text Available Silvopastoral systems present difficulties in their management due to their complexity. When trees are planted into grasslands, they need protection from livestock to prevent damage from trampling or browsing, especially during early years of establishment. One of the common post-planting protective treatments is the protection of individual trees with shelters. Trees also need protection from competition from herbaceous vegetation. The aim of present study was to evaluate the effects of using different types of tree shelters and of controlling competing herbaceous vegetation on the growth of planted young trees and, to assess the effects of heavy shading on the herbage production and composition. The study was conducted in a Fraxinus angustifolia silvopastoral system of a 2 x 2.5 m spacing plantation in northern Greece. The effects of solid-walled (tubex and handmade by greenhouse nylon and wire mesh tree shelters as well as of herbicide application and mechanical removal of the competing herbaceous vegetation on tree height, height increment and the crown surface area of the trees were tested. The effects of artificial shading (80% on the production of the natural herbaceous vegetation were also investigated. All measurements were recorded three years after plantation. The use of solid wall tubex shelters resulted in higher tree height and higher crown surface area in comparison to the other tested shelters. The solid wall Nylon shelters were more beneficial to the above growth parameters than the wire mesh ones. Both vegetation control treatments proved beneficial to all the growth parameters of Fraxinus angustifolia. The artificially applied heavy shading reduced herbage production by 54% compared to the control. The results indicated that post planting treatments in the Mediterranean droughty conditions are essential for the success of this tree species establishment. Furthermore, the later thinning of the dense spacing is important to

Role of six European tree species and land-use legacy for nitrogen and water budgets in forests

DEFF Research Database (Denmark)

Riis Christiansen, Jesper; Vesterdal, Lars; Callesen, Ingeborg

2010-01-01

-year-old common garden design with stands of common ash (Fraxinus excelsior), European beech (Fagus sylvatica L.), pedunculate oak (Quercus robur), small-leaved lime (Tilia cordata Mill.), sycamore maple (Acer pseudoplatanus) and Norway spruce (Picea abies [L.] Karst.) replicated at two sites...... in Denmark, Mattrup and Vallø during 2 years. Mean annual percolation below the root zone (mm yr−1±SE, n=4) ranked in the following order: maple (351±38)>lime (284±32), oak (271±25), beech (257±30), ash (307±69)≫ spruce (75±24). There were few significant tree species effects on N fluxes. However, the annual...... mean N throughfall flux (kg N ha−1 yr−1±SE, n=4) for spruce (28±2) was significantly larger than for maple (12±1), beech (11±1) and oak (9±1) stands but not different from that of lime (15±3). Ash had a low mean annual inorganic N throughfall deposition of 9.1 kg ha−1, but was only present at Mattrup...

White ash (Fraxinus americana) decline and mortality: the role of site nutrition and stress history

Science.gov (United States)

Alejandro A. Royo; Kathleen S. Knight

2012-01-01

Over the past century, white ash (Fraxinus americana) populations throughout its range have deteriorated as a result of declining tree health and increased mortality rates. Although co-occurring factors including site nutritional deficiencies and punctuated stress events (e.g., defoliations, drought) are hypothesized to trigger white ash decline,...

The studies on ash dying (Fraxinus excelsior L. in the Włoszczowa Forest Unit stands

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Tadeusz Kowalski

2012-12-01

Full Text Available The studies were carried out in the Włoszczowa Forest Unit, in 9 ash stands differing in respect of age, origin (natural, artificial, site and in the nursery on 3 quarters differing due to a silvicultural method (transplanted and not transplanted and seedlings age. In each stand an analysis of disease symptoms was carried out on 100 trees (2 - 20 years old stands or 50 trees (21 - 80 years old stands growing side by side in central part of the stand, while in the nursery in each block 200 seedlings were analyzed (4 sectors with 50 seedlings each. From the infected seedlings and trees 120 fragments of dead branches, living branches with cankers, and dead roots were taken. Identification of fungi was made on the basis of fructification and over 300 isolations of fungi on malt agar medium. The most frequent disease symptoms in ash stands were: the dead top (34.7% trees, the dying of whole branches (83.5%, the dying of the top of branches (20.1%, the occurrence of healed (36.0% and unhealed cankers (18.9% and the slime flux (23.7% on the trunk, also the chlorosis of leaves (7.5% and their atrophy (11.2%. Most of the types of disease symptoms appeared irrespectively of the tree age, origin and site, sometimes showing only a difference in the frequency of occurrence. On the seedlings in the nursery the shoot discolouration, healed and unhealed cankers on shoots and necrosis of a part of leaves were recorded most frequently. Disease symptoms occurred more frequently on 4-year-old seedlings in comparison with 3-year-old. In respect of transplanted seedlings the leaves dying was more frequent. Within cankers and on dead tops of shoots the most frequent were: Alternaria alternata, Chalara sp., Cytospora ambiens, Diplodia mutila, Fusarium lateritium, Gloeosporidiella turgida, Phomopsis controversa and Phomopsis scobina. In sparsely found dead roots of living trees appeared mostly: Cryptosporiopsis radicicola, Cylindrocarpon destructans and Phialocephala

Agrobacterium-mediated genetic transformation and plant regeneration of the hardwood tree species Fraxinus profunda

Science.gov (United States)

Micah E. Stevens; Paula M. Pijut

2014-01-01

Using mature hypocotyls as the initial explants, an Agrobacterium tumefaciens-mediated genetic transformation system was successfully developed for pumpkin ash (Fraxinus profunda). This transformation protocol is an invaluable tool to combat the highly aggressive, non-native emerald ash borer (EAB), which has the potential to...

Investigation of seedlings growth and development of some trees and shrubs grown on energetic ashes of two types. [Acer negundo; Fraxinus pennsylvanica; Populus alba; Myricaria germanica

Energy Technology Data Exchange (ETDEWEB)

Kluczynski, B

1973-01-01

Pot experiments concerning the degree of resistance, of chosen species of trees and shrubs to unfavorable physical and chemical properties of energetic ashes, obtained from burning brown (K) and pit (O) coal, were carried out. Seeds were sown out in prepared substrates, in 8 combinations. The investigation consisted of two parts. Seeds of 11 species of trees and shrubs and 1 herb plant were used in the first part. Seeds of 6 species of trees and shrubs were used in the second part. All the environmental variants were investigated in 4 replications (replication = pot). Each species was evaluated according to several features determining its usefulness on various substrates. These features were divided into two groups, characterizing seedlings survival (feature group ..cap alpha..) and health conditions and general vitality (feature group ..beta..). The obtained results indicate a need of examining the usefulness for dump recultivation in field conditions of Acer negundo, Fraxinus pennsylvanica, Populus alba and probably Myricaria germanica. 8 references, 17 tables.

Variability in radial sap flux density patterns and sapwood area among seven co-occurring temperate broad-leaved tree species.

Science.gov (United States)

Gebauer, Tobias; Horna, Viviana; Leuschner, Christoph

2008-12-01

Forest transpiration estimates are frequently based on xylem sap flux measurements in the outer sections of the hydro-active stem sapwood. We used Granier's constant-heating technique with heating probes at various xylem depths to analyze radial patterns of sap flux density in the sapwood of seven broad-leaved tree species differing in wood density and xylem structure. Study aims were to (1) compare radial sap flux density profiles between diffuse- and ring-porous trees and (2) analyze the relationship between hydro-active sapwood area and stem diameter. In all investigated species except the diffuse-porous beech (Fagus sylvatica L.) and ring-porous ash (Fraxinus excelsior L.), sap flux density peaked at a depth of 1 to 4 cm beneath the cambium, revealing a hump-shaped curve with species-specific slopes. Beech and ash reached maximum sap flux densities immediately beneath the cambium in the youngest annual growth rings. Experiments with dyes showed that the hydro-active sapwood occupied 70 to 90% of the stem cross-sectional area in mature trees of diffuse-porous species, whereas it occupied only about 21% in ring-porous ash. Dendrochronological analyses indicated that vessels in the older sapwood may remain functional for 100 years or more in diffuse-porous species and for up to 27 years in ring-porous ash. We conclude that radial sap flux density patterns are largely dependent on tree species, which may introduce serious bias in sap-flux-derived forest transpiration estimates, if non-specific sap flux profiles are assumed.

ASSESMENT OF MAINTENANCE OF TREE STAND IN NATURE RESERVE "SKARPA WIŚLICKA" IN SILESIAN FOOTHILLS

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Damian Chmura

2017-04-01

Full Text Available The forest “Skarpa Wiślicka” is nature reserve that protects remnants of former primevail forest in the territory of Wiślica. It also is included in NATURA 2000 area (Cieszyńskie Źródła Tufowe code PLH240001. The aim of the present study was to valorization of treestand of this protected object. Amongst 19 observed tree species, 11 were studied in detail (232 randomly selected individuals. Dendrometry measurements, health tree were assessed. The attention was paid to presence of coarse woody debris as well. For the purpose of the latter decomposition stage was characterized. The studies demonstrated that as many as 69 individuals scored size for nature monuments (circumference and diameter at breast height. The elm Ulmus glabra prevailed (25 individuals have higher value than 220 cm of circumference and the least abundant is ash Fraxinus excelsior (2 higher than 250 cm. More than 50% of trees were characterized by damages i.e. losses of bark, dried or broken branches. Amount of coarse woody debris is not enough. Amongst logs I degree of decomposition dominated (27 logs, whereas weighted mean is 2.93 in 8-degree scale. To sum up it can be concluded that the number of trees that deserve the protection of the rank of a natural monument is very high. It reflects favorable conditions of development of forest communities in the territory of “Skarpa Wiślicka”. While relatively small amount of dead wood and low mean degree of decomposition indicates the impact of forest management i.e. frequent removal of dead wood.

Effects of cutting time, stump height, and herbicide application on ash (Fraxinus spp.) stump sprouting and colonization by emerald ash borer (Agrilus planipennis)

Science.gov (United States)

Toby R. Petrice; Robert A. Haack

2011-01-01

Efforts to eradicate or slow the spread of emerald ash borer (EAB) (Agrilus planipennis Fairmaire [Coleoptera: Buprestidae]) include cutting infested and nearby uninfested ash (Fraxinus spp.) trees. However, ash trees readily sprout after they have been cut, providing potential host material for EAB. In 2004-2005, we conducted...

EAB induced tree mortality impacts ecosystem respiration and tree water use in an experimental forest

Science.gov (United States)

Charles E. Flower; Douglas J. Lynch; Kathleen S. Knight; Miquel A. Gonzales-Meler

2011-01-01

The invasive emerald ash borer (Agrilus planipennis Fairmaire, EAB) has been spreading across the forest landscape of the Midwest resulting in the rapid decline of ash trees (Fraxinus spp.). Ash trees represent a dominant riparian species in temperate deciduous forests of the Eastern United States (USDA FIA Database). Prior...

Impact of tree species on soil carbon stocks and soil acidity in southern Sweden

International Nuclear Information System (INIS)

Oostra, Swantje; Majdi, Hooshang; Olsson, Mats

2006-01-01

The impact of tree species on soil carbon stocks and acidity in southern Sweden was studied in a non-replicated plantation with monocultures of 67-year-old ash (Fraxinus excelsior L.), beech (Fagus silvatica L.), elm (Ulmus glabra Huds.), hornbeam (Carpinusbetulus L.), Norway spruce (Picea abies L.) and oak (Quercus robur L.). The site was characterized by a cambisol on glacial till. Volume-determined soil samples were taken from the O-horizon and mineral soil layers to 20 cm. Soil organic carbon (SOC), total nitrogen (TN), pH (H2O), cation-exchange capacity and base saturation at pH 7 and exchangeable calcium, magnesium, potassium and sodium ions were analysed in the soil fraction hornbeam > oak > beech > ash > elm. The pH in the O-horizon ranged in the order elm > ash > hornbeam > beech > oak > spruce. In the mineral soil, SOC and TN ranged in the order elm > oak > ash = hornbeam > spruce > beech, i.e. partly reversed, and pH ranged in the same order as for the O-horizon. It is suggested that spruce is the best option for fertile sites in southern Sweden if the aim is a high carbon sequestration rate, whereas elm, ash and hornbeam are the best solutions if the aim is a low soil acidification rate

Assessing future suitability of tree species under climate change by multiple methods: a case study in southern Germany

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Helge Walentowski

2017-07-01

Full Text Available We compared results derived using three different approaches to assess the suitability of common tree species on the Franconian Plateau in southern Germany under projected warmer and drier climate conditions in the period 2061-2080. The study area is currently a relatively warm and dry region of Germany. We calculated species distribution models (SDMs using information on species’ climate envelopes to predict regional species spectra under 63 different climate change scenarios. We complemented this with fine-scale ecological niche analysis using data from 51 vegetation surveys in seven forest reserves in the study area, and tree-ring analysis (TRA from local populations of five tree species to quantify their sensitivity to climatic extreme years. The SDMs showed that predicted future climate change in the region remains within the climate envelope of certain species (e.g. Quercus petraea, whilst for e.g. Fagus sylvatica, future climate conditions in one third of the scenarios are too warm and dry. This was confirmed by the TRA: sensitivity to drought periods is lower for Q. petraea than for F. sylvatica. The niche analysis shows that the local ecological niches of Quercus robur and Fraxinus excelsior are mainly characterized by soils providing favorable water supply than by climate, and Pinus sylvestris (planted is strongly influenced by light availability. The best adapted species for a warmer and potentially drier climate in the study region are Acer campestre, Sorbus torminalis, S. aria, Ulmus minor, and Tilia platyphyllos, which should therefore play a more prominent role in future climate-resilient mixed forest ecosystems.

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

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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.

Variation in root wood anatomy

NARCIS (Netherlands)

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.

Relationships between browsing damage and the species dominance by the highly food-attractive and less food-attractive trees

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Petr Čermák

2011-01-01

Full Text Available The paper analyses data on the browsing damage to Acer pseudoplatanus, Carpinus betulus, Fraxinus excelsior, Quercus spp., Tilia cordata and Fagus sylvatica. Field research was carried out in the period 2007–2010 and analysed data came from 33 transects at 10 localities with the various abundance of game in the CR (everywhere Capreolus capreolus, on several plots also Cervus elaphus, Ovis musimon or Dama dama. Trees were monitored up to a height of 150 cm in natural regeneration under stands and in plantations and the occurrence was noted of new browsing damage. Differences between the percentage of damaged individuals of the given species of a food-attractive species (A. p., C. b., F. e. and the percentage of damaged individuals of all tree species on a transect as well as the proportion of these parameters correlate negatively with the given species dominance and thus, they appear to be suitable parameters for the analysis of relationships between the damage intensity and dominance. The higher the percentage proportions of highly food-attractive species and the lower the percentage of less-attractive species, the lower the relative intensity of damage to highly food-attractive species. At the same time, the higher the percentage proportion of highly food-attractive species and the lower the percentage of less-attractive species then the lower a difference between damage to less food-attractive species and all species.

Influence of fumes from industrial works on the seasonal development of trees and shrubs

Energy Technology Data Exchange (ETDEWEB)

Antipov, V G

1957-01-01

Phenological observations were made at Leningrad in 1953 and 1954 on woody species growing near three chemical works. Controls were observed in an unpolluted park. Data on the relative incidence of the main phenological phases (flushing, flowering, fruiting, autumn coloration and leaf-fall) are tabulated separately for each works. Pollution curtailed the growing season to some degree in all species; its effect in hastening coloration and leaf-fall was more marked than in retarding the spring phases. The least susceptible species were Populus balsamifera, P. suaveolens, Alnus incana, Quercus robur, Fraxinus excelsior, Amelanchier rotundifolia and Lonicera tatarica. Species unsuited for cultivation in these conditions are Caragana arborescens, Prunus padus, Tilia cordata, Ulmus laevis, Crataegus oxyacantha, Betula pubescens and B. verrucosa.

Twenty-five years of biomonitoring lead in the Frankfurt/Main area.

Science.gov (United States)

Ballach, Hans-Joachim; Wittig, Rüdiger; Wulff, Svenja

2002-01-01

The present study is an example of the historical monitoring of heavy metals. The specific question it aims to explore is: to what extent has the lead content of selected organisms used for biomonitoring in Frankfurt/Main--one of the cities in Germany most heavily affected by automobile traffic--changed as a result of legislation on leaded gasoline? Data on the lead content of the moss species Bryum argenteum Hedw. from the years 1974, 1975 and 1978 and data on the lead content of the outer bark of the ash species Fraxinus excelsior L. from 1973 served as the basis for the repeated measurements. Remeasurement was successful in 76.5% (i.e. 124 trees at 26 growth sites). The study produced the following results: As was expected, the lead content of the short-term accumulator Bryum argenteum Hedw. was distinctly lowered with a decreasing particulate lead concentration. However, the reduction factor varied greatly between the different growth sites. On the other hand, the lead content measured in the outer bark layers of Fraxinus excelsior L. has risen markedly during the past two decades. Whereas in 1973 nearly all trees examined displayed very low concentrations of lead (225 ppm). Various factors have to be taken into account to explain this increase. First of all, bark is a long-term accumulator for heavy metals like lead and its enrichment capacity could have increased as the surface becomes rougher over time. Furthermore, lead is most probably leached out of the bark to a lesser degree now than in the 1970s, owing to the reduced concentration of sulphuric acid in the rain. The dramatic growth of automobile traffic in the Frankfurt/Main area during the period covered by the study undoubtedly plays an important role as well.

To treat or not to treat: Diminishing effectiveness of emamectin benzoate tree injections in ash trees heavily infested by emerald ash borer

Science.gov (United States)

Charles E. Flower; Jennifer E. Dalton; Kathleen S. Knight; Marie Brikha; Miquel A. Gonzalez-Meler

2015-01-01

Emerald ash borer (EAB), a non-native invasive tree-boring beetle, is the primary agent behind thewidespread mortality of ash trees (Fraxinus spp.) in both natural forests and urban areas of North Amer-ica. While a variety of insecticide options have been adopted for protection against EAB attacks, little hasbeen reported on the success of...

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

DEFF Research Database (Denmark)

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

2008-01-01

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...

Production of human interferon alfa 2b in plants of Nicotiana excelsior by Agrobacterium-mediated transient expression.

Science.gov (United States)

Sindarovska, Y R; Gerasymenko, I M; Sheludko, Y V; Olevinskaya, Z M; Spivak, N Y; Kuchuk, N V

2010-01-01

Human interferon alpha2b gene was transiently expressed in Nicotiana excelsior plants. Fusion with N. plumbaginifolia calreticulin signal peptide for improved apoplast targeting and carrying out the expression under optimized conditions resulted in maximal interferon activity of 3.2 x 10(3) IU/g fresh weight (FW) with an average of 2.1 +/- 0.8 x 10(3) IU/g FW. It proves that N. excelsior is a suitable host for Agrobacterium-mediated transient expression of genes encoding physiologically active human proteins. The transient expression conditions optimized for GFP marker protein were confirmed to be preferable for hIFN alpha2b.

Desert Southwest Community Tree Guide: Benefits, Costs and Strategic Planting

Science.gov (United States)

Greg McPherson; J.R. Simpson; P.J. Peper; S.E. Maco; Q. Xiao; E. Mulrean

2004-01-01

This report quantifies benefits and costs for typical large-, medium-, small-stature, deciduous trees (Fraxinus uhdei, Prosopis chilensis, Acacia farnesiana), as well as a conifer (Pinus halapensis). The analysis assumed that trees were planted in a residential yard site or a public (street/park) site, a 40-year time frame, and...

Susceptibility of various tree species to SO/sub 2/, HF and magnesite dust pollutions

Energy Technology Data Exchange (ETDEWEB)

Pollanschutz, J

1969-01-01

The investigations covered an area polluted with SO/sub 2/ and magnesite, with SO/sub 2/ and HF, and with HF. With the aid of an increment borer, the growth of the trees was measured; in other cases, the power of endurance was estimated. In the environment of a magnesite plant magnesite dust and SO/sub 2/ pollution caused growth reduction (in decreasing order) in Abies alba, Picea abies and Pinus sylvestris. Larix decidua appeared to be by far the most resistant against both pollutants. Fagus sylvatica still showed a growth increase, though leaf burn symptoms were present; this might be due to fertilization with MgSO/sub 4/ through the leaves. When polluted with both SO/sub 2/ and HF, the (increasing) order was: Populus tremula, Fraxinus excelsior, Fagus + Acer, Picea + Pinus, Larix. Though no differences between Pinus and Picea was found here, it was striking that in the latter species the variation in susceptibility was much greater than in Pinus, which may be important for future selection work. In an atmosphere polluted solely with HF, Pinus showed a greater resistance than Picea and Abies, but it seemed that in its youth, Abies was at least as resistant as Picea. Symptoms do not always correspond with growth reduction and yield losses, and an important growth reduction may occur before any clear symptoms can be observed. Breeding for resistance should be encouraged, especially in spruce.

Black Ash (Fraxinus nigra Marsh.): Local ecological knowledge of site characteristics and morphology associated with basket-grade specimens in New England (USA)

Science.gov (United States)

Allaire K. Diamond; Marla R. Emery

2011-01-01

Fraxinus nigra Marsh. is a small, relatively uncommon tree with large social significance. Known as black ash or brown ash, it rarely exceeds 18 meters (60 feet) in height or 30-50 centimeters (12-20 inches) in diameter. In the U.S. states where the species occurs, its percentage of forest composition ranges from 0.01% in Kentucky to 6.00% in...

Lethal trap trees: a potential option for emerald ash borer (Agrilus planipennis Fairmaire) management

Science.gov (United States)

Deborah G McCullough; Therese M. Poland; Phillip A. Lewis

2015-01-01

BACKGROUND: Economic and ecological impacts of ash (Fraxinus spp.) mortality resulting from emerald ash borer (EAB) (Agrilus planipennis Fairmaire) invasion are severe in forested, residential and urban areas. Management options include girdling ash trees to attract ovipositing adult beetles and then destroying infested trees...

Transcriptomic signatures of ash (Fraxinus spp. phloem.

Directory of Open Access Journals (Sweden)

Xiaodong Bai

2011-01-01

Full Text Available Ash (Fraxinus spp. is a dominant tree species throughout urban and forested landscapes of North America (NA. The rapid invasion of NA by emerald ash borer (Agrilus planipennis, a wood-boring beetle endemic to Eastern Asia, has resulted in the death of millions of ash trees and threatens billions more. Larvae feed primarily on phloem tissue, which girdles and kills the tree. While NA ash species including black (F. nigra, green (F. pennsylvannica and white (F. americana are highly susceptible, the Asian species Manchurian ash (F. mandshurica is resistant to A. planipennis perhaps due to their co-evolutionary history. Little is known about the molecular genetics of ash. Hence, we undertook a functional genomics approach to identify the repertoire of genes expressed in ash phloem.Using 454 pyrosequencing we obtained 58,673 high quality ash sequences from pooled phloem samples of green, white, black, blue and Manchurian ash. Intriguingly, 45% of the deduced proteins were not significantly similar to any sequences in the GenBank non-redundant database. KEGG analysis of the ash sequences revealed a high occurrence of defense related genes. Expression analysis of early regulators potentially involved in plant defense (i.e. transcription factors, calcium dependent protein kinases and a lipoxygenase 3 revealed higher mRNA levels in resistant ash compared to susceptible ash species. Lastly, we predicted a total of 1,272 single nucleotide polymorphisms and 980 microsatellite loci, among which seven microsatellite loci showed polymorphism between different ash species.The current transcriptomic data provide an invaluable resource for understanding the genetic make-up of ash phloem, the target tissue of A. planipennis. These data along with future functional studies could lead to the identification/characterization of defense genes involved in resistance of ash to A. planipennis, and in future ash breeding programs for marker development.

Promotion of adventitious root formation of difficult-to-root hardwood tree species

Science.gov (United States)

Paula M. Pijut; Keith E. Woeste; Charles H. Michler

2011-01-01

North American hardwood tree species, such as alder (Alnus spp.), ash (Fraxinus spp.), basswood (Tilia spp.), beech (Fagus spp.), birch (Betula spp.), black cherry (Prunus seratina), black walnut (Juglans nigra), black willow (...

Tree Species Identity Shapes Earthworm Communities

DEFF Research Database (Denmark)

Schelfhout, Stephanie; Mertens, Jan; Verheyen, Kris

2017-01-01

Earthworms are key organisms in forest ecosystems because they incorporate organic material into the soil and affect the activity of other soil organisms. Here, we investigated how tree species affect earthworm communities via litter and soil characteristics. In a 36-year old common garden...... of soil and foliar litter, and determined the forest floor turnover rate and the density and biomass of the earthworm species occurring in the stands. Tree species significantly affected earthworm communities via leaf litter and/or soil characteristics. Anecic earthworms were abundant under Fraxinus, Acer...

Ash (Fraxinus excelsior) seed quality in relation to seed ...

African Journals Online (AJOL)

Jane

2011-07-18

Jul 18, 2011 ... bottles were seal-locked and kept in the accelerated ageing cham- ber at three ... Hundred (100) seeds of each treatment were performed in plastic ..... by heat stress: the activation state of Rubisco as a limiting factor in.

The Newspaper that Made Its Way to National Life. The First Years of Excelsior (1916- 1932

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Arno Burkholder de la Rosa

2009-04-01

Full Text Available This work covers the history of the Mexican newspaper  Excelsior between  1916 and 1932. The author  examines the context in which  the newspaper  was born  —triumph of Constitutionalism and conflicts  between  its constituting groups—  and  the survival and  strengthening of  business  journalism,  which  was born during the Porfiriato and now had to negotiate with revolutionary leaders. Excelsior maintained  during its first stage a “moderately conservative” editorial line, which  brought about trouble with the governments of Álvaro Obregón and Plutarco Elías Calles, but which also led to a growing prestige among its readers —urban middle— and high —class in the capital and other cities. This period ended when the newspaper failed to overcome its problems with the revolutionary regimes and had to face a deep economic crisis leading to bankruptcy.

Distribution of trunk-injected 14C-imidacloprid in ash trees and effects on emerald ash borer (Coleoptera: Buprestidae) adults

Science.gov (United States)

David Mota-Sánchez; Bert M. Cregg; Deborah G. McCullough; Therese M. Poland; Robert M. Hollingworth

2009-01-01

The emerald ash borer (EAB), Agrilus planipennis (Coleoptera: Buprestidae) is a destructive exotic pest of North American ash (Fraxinus sp.) trees. Trunk injection of imidacloprid is commonly used to protect landscape ash trees from A. planipennis damage. Efficacy can vary and little is known about the...

Ash Dieback on Sample Points of the National Forest Inventory in South-Western Germany

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Rasmus Enderle

2018-01-01

Full Text Available The alien invasive pathogen Hymenoscyphus fraxineus causes large-scale decline of European ash (Fraxinus excelsior. We assessed ash dieback in Germany and identified factors that were associated with this disease. Our assessment was based on a 2015 sampling of national forest inventory plots that represent a supra-regional area. In the time from 2012 to 2015, the number of regrown ash trees corresponded to only 42% of the number of trees that had been harvested or died. Severe defoliation was recorded for almost 40% of the living trees in 2015, and more than half of the crowns mainly consisted of epicormic shoots. Necroses were present in 24% of root collars. A total of 14% of the trees were in sound condition, which sum up to only 7% of the timber volume. On average, trees of a higher social status or with a larger diameter at breast height were healthier. Collar necroses were less prevalent at sites with a higher inclination of terrain, but there was no evidence for an influence of climatic variables on collar necroses. The disease was less severe at sites with smaller proportions of the basal area of ash compared to the total basal area of all trees and in the north-eastern part of the area of investigation. The regeneration of ash decreased drastically.

Physical Characterisation and Quantification of Total Above Ground Biomass Derived from First Thinnings for Wood Fuel Consumption in Ireland

OpenAIRE

Mockler, Nicholas

2013-01-01

Comprehensive knowledge of wood fuel properties assists in the optimisation of operations concerned with the harvesting, seasoning, processing and conversion of wood to energy. This study investigated the physical properties of wood fuel. These properties included moisture content and basic density. The field work also allowed for the quantification of above ground biomass partitions. The species investigated were alder (Alnus glutinosa), ash (Fraxinus excelsior L.), birch (Betula spp.), lodg...

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

International Nuclear Information System (INIS)

Schaub, M.; Skelly, J.M.; Zhang, J.W.; Ferdinand, J.A.; Savage, J.E.; Stevenson, R.E.; Davis, D.D.; Steiner, K.C.

2005-01-01

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 (ψ L ) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (g wv ) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (P n ), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P wv and P n 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

Agrobacterium-mediated genetic transformation of Fraxinus americana hypocotyls

Science.gov (United States)

Kaitlin J. Palla; Paula M. Pijut

2015-01-01

An Agrobacterium tumefaciens-mediated genetic transformation system was successfully developed for white ash (Fraxinus americana) using hypocotyls as the initial explants. Hypocotyls isolated from mature embryos germinated on Murashige and Skoog (MS) medium supplemented with 22.2 µM 6-benzyladenine (BA) and 0.5 µM...

Comparison of various pulping characteristic of Fraxinus angustifolia ...

African Journals Online (AJOL)

Handsheets made from different pulping methods were compared with each other for strength and optical properties. Strength properties were found to be higher for kraft and kraft + anthraquinone processes, while optical properties were found to be higher for cold soda and NSSC processes. Key words: Ash, Fraxinus ...

Structural Relationships Of Selected Tree Species at Several Mid-Latitude Deciduous Forest Sites in Virginia

Science.gov (United States)

1999-09-01

are included in the deciduous analyses. They are mockernut hickory { Carya tomentosa), American elm {Ulmus americana), pecan { Carya illinoensis ), and...alba, white ash (Fraxinus americana), and pecan ( Carya illinoensis ). A number of these trees have plaques indicating the dates of planting (late 1700s

Stem water storage in five coexisting temperate broad-leaved tree species: significance, temporal dynamics and dependence on tree functional traits.

Science.gov (United States)

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

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

OpenAIRE

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...

Attraction of the emerald ash borer to ash trees stressed by girdling, herbicide treatment, or wounding

Science.gov (United States)

Deborah McCullough; Therese Poland; David. Cappaert

2009-01-01

New infestations of emerald ash borer, Agrilus planipennis Fairmaire, an invasive pest native to Asia, are difficult to detect until densities build and symptoms appear on affected ash (Fraxinus spp). We compared the attraction of A. planipennis to ash trees stressed by girdling (bark and phloem removed...

Assortative mating and differential male mating success in an ash hybrid zone population

Directory of Open Access Journals (Sweden)

Frascaria-Lacoste Nathalie

2006-11-01

Full Text Available Abstract Background The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species Fraxinus excelsior L. (common ash and F. angustifolia Vahl (narrow-leaved ash, which is composed of individuals of the two species and several hybrid types. This population is structured by flowering time: the F. excelsior individuals flower later than the F. angustifolia individuals, and the hybrid types flower in-between. Hybrids are scattered throughout the population, suggesting favorable conditions for their local adaptation. We estimate jointly the best-fitting dispersal kernel, the differences in male fecundity due to variation in phenotypic traits and level of parasite attack, and the strength of assortative mating due to differences in flowering phenology. In addition, we assess the effect of accounting for genotyping error on these estimations. Results We detected a very high pollen immigration rate and a fat-tailed dispersal kernel, counter-balanced by slight phenological assortative mating and short-distance pollen dispersal. Early intermediate flowering hybrids, which had the highest male mating success, showed optimal sex allocation and increased selfing rates. We detected asymmetry of gene flow, with early flowering trees participating more as pollen donors than late flowering trees. Conclusion This study provides striking evidence that long-distance gene flow alone is not sufficient to counter-act the effects of assortative mating and selfing. Phenological assortative mating and short-distance dispersal can create temporal and spatial structuring that appears

Agrobacterium-mediated transformation of Fraxinus pennsylvanica hypocotyls and plant regeneration

Science.gov (United States)

Ningxia Du; Paula M. Pijut

2009-01-01

A genetic transformation protocol for green ash (Fraxinus pennsylvanica) hypocotyl explants was developed. Green ash hypocotyls were transformed using Agrobacterium tumefaciens strain EHA105 harboring binary vector pq35GR containing the neomycin phosphotransferase (nptII) and β-glucuronidase (GUS) fusion...

[Occurrence and control of frost in Tilia amurensis and Fraxinus mandshurica young plantations].

Science.gov (United States)

Chen, X; Zhang, Y; Ma, H

2000-12-01

The changes of minimum temperature periodical biological phenomena and frost in yound Tilia amurensis and Fraxinus mandshurica plantation stands were systematically analyzed based on the vertical gradient observation and plot investigation. Meanwhile, the resistance of Tilia amurensis to late frost was also studied. The results showed that the phenophase of T. amurensis was later than that of F. mandshurica. Influenced by significant temperature inversions in this area, the phenophase of T. amurensis and F. mandshurica changed regularly in different aspects and slope positions. The sprouts on west slope started earlier than that on east slope. The higher they grew on the slope, the earlier they sprouted, with the earliest sprout at the top of slope. Late frost in this area only took place when the trees were sprouting, but air temperature decreased significantly at the same time. The degree of injury from the late frost could be controlled effectively by selecting suitable site. Sites down the slope, especially the east slope, were not suitable for T. amurensis and F. mandshurica plantation in this research area. Chemical treatment and biological shading could prevent late frost injury through putting off sprout. Mixed plantations could prevent F. mandshurica and T. anurensis from late frost injury significantly, and the frost injury index and the proportion of the tree number of different injury grades were lower than those in pure stands.

Effects of the emerald ash borer invasion on the community composition of arthropods associated with ash tree boles

Science.gov (United States)

Emerald ash borer (EAB), Agrilus planipennis Fairmaire is an invasive non-native wood-boring beetle that has killed hundreds of millions of ash trees (Fraxinus spp.) in North America, and threatens to extirpate the ecological services provided by the genus. Identifying the arthropod community assoc...

Introduced pathogens found on ornamentals, strawberry and trees in Finland over the past 20 years

Directory of Open Access Journals (Sweden)

A. LILJA

2008-12-01

Full Text Available The comparative ease and speed of international trade and travel have enabled or enhanced the spread of pests around the globe. For example, trade in ornamental plants has bolstered the spread of alien Oomycetes such as pathogenic species of Phytophthora. To date, four Phytophthora species have been identified in Finland: P. cactorum on Fragaria x ananassa, Betula pendula and Rhododendron spp., P. plurivora on Rhododendron spp. and Syringa vulgaris, and P. pini and P. ramorum on Rhododendron spp. The ascomycete Colletotrichum acutatum, which was listed as a quarantine pathogen by the European Union until 2009, was introduced in 2000 and can survive in plant debris over two winters in Finland. Positive PCR results have also been obtained from bait plants grown in soil collected from locations where diseased Fragaria x ananassa plants had earlier been destroyed. In the mid-1990s, there was an epidemic of foliar rust caused by the Asian basidiomycete Melampsoridium hiratsukanum on Alnus glutinosa and A. incana. Recently, two ascomycetes that have been introduced are Dothistroma septosporum (responsible for red band needle blight on Pinus sylvestris and Chalara fraxinea (causing ash decline on Fraxinus excelsior.;

Progress and challenges of protecting North American ash trees from the emerald ash borer using biological control

Science.gov (United States)

Jian Duan; Leah Bauer; Roy van Driesche; Juli. Gould

2018-01-01

After emerald ash borer (EAB), Agrilus planipennis Fairmaire, was discovered in the United States, a classical biological control program was initiated against this destructive pest of ash trees (Fraxinus spp.). This biocontrol program began in 2007 after federal regulatory agencies and the state of Michigan approved release of...

Uranium mobility across annual growth rings in three deciduous tree species.

Science.gov (United States)

McHugh, Kelly C; Widom, Elisabeth; Spitz, Henry B; Wiles, Gregory C; Glover, Sam E

2018-02-01

Black walnut (Juglans nigra), slippery elm (Ulmus rubra), and white ash (Fraxinus americana) trees were evaluated as potential archives of past uranium (U) contamination. Like other metals, U mobility in annual growth rings of trees is dependent on the tree species. Uranium concentrations and isotopic compositions (masses 234, 235, 236, and 238) were analyzed by thermal ionization mass spectrometry to test the efficacy of using tree rings to retroactively monitor U pollution from the FFMPC, a U purification facility operating from 1951 to 1989. This study found non-natural U (depleted U and detectable 236 U) in growth rings of all three tree species that pre-dated the start of operations at FFMPC and compositional trends that did not correspond with known contamination events. Therefore, the annual growth rings of these tree species cannot be used to reliably monitor the chronology of U contamination. Copyright © 2017 Elsevier Ltd. All rights reserved.

The susceptibility of Asian, European and North American Fraxinus species to the ash dieback pathogen Hymenoscyphus fraxineus reflects their phylogenetic history

DEFF Research Database (Denmark)

Nielsen, Lene Rostgaard; McKinney, Lea Vig; Hietala, Ari M.

2017-01-01

susceptibility where closely related Asian, European and North American species in section Fraxinus had relatively high levels of H. fraxineus DNA in the leaves and supported high production of apothecia. Leaves from some North American species also contained relatively high levels of H. fraxineus DNA, supported...... that there is species-specific variation in disease susceptibility among European and North American Fraxinus species, but a wider comparison at the genus level has been missing so far. We assessed disease symptoms and pathogen apothecium development in 17 Fraxinus species from Asia, Europe and North America exposed...

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

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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.

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

NARCIS (Netherlands)

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

Can Emerald ash borer, Agrilus planipennis (Coleoptera: Buprestidae), emerge from logs two summers after infested trees are cut?

Science.gov (United States)

Toby R. Petrice; Robert A. Haack

2007-01-01

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of ash trees (Fraxinus spp.) in North America. Much of EAB's range expansion has been attributed to human-assisted movement of infested items such as ash logs and firewood. It is unclear the amount of time that logs cut...

Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

International Nuclear Information System (INIS)

Novak, K.; Schaub, M.; Fuhrer, J.; Skelly, J.M.; Hug, C.; Landolt, W.; Bleuler, P.; Kraeuchi, N.

2005-01-01

Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures

Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

Energy Technology Data Exchange (ETDEWEB)

Novak, K. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)]. E-mail: kristopher.novak@wsl.ch; Schaub, M. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Fuhrer, J. [Swiss Federal Research Station for Agroecology and Agriculture FAL, 8046 Zurich (Switzerland); Skelly, J.M. [Department of Plant Pathology, The Pennsylvania State University, University Park, PA 16802 (United States); Hug, C. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Landolt, W. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Bleuler, P. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Kraeuchi, N. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)

2005-07-15

Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures.

Examining the influences of tree-to-tree competition and climate on size-growth relationships in hydric, multi-aged Fraxinus nigra stands

Science.gov (United States)

Christopher E. Looney; Anthony W. D' Amato; Shawn Fraver; Brian J. Palik; Michael R. Reinikainen

2016-01-01

Most research on tree-tree competition and size-growth relationship (SGR – a stand-level metric that infers the relative efficiency with which different sized trees utilize available resources) has focused on upland systems. It is unclear if inferences from these studies extend to wetland forests. Moreover, no study to date has thoroughly investigated the relationship...

Strategic removal of host trees in isolated, satellite infestations of emerald ash borer can reduce population growth

Science.gov (United States)

Samuel J. Fahrner; Mark Abrahamson; Robert C. Venette; Brian H. Aukema

2017-01-01

Emerald ash borer is an invasive beetle causing significant mortality of ash trees (Fraxinus spp.) in North America and western Russia. The invasive range has expanded to more than half of the states in the United States since the initial detection in Michigan, USA in 2002. Emerald ash borer is typically managed with a combination of techniques...

Lead pollution due to exhaust gases. [Celtis occidentalis; fraxinus angustifolia; aesculus hippocastanum; hedera helix

Energy Technology Data Exchange (ETDEWEB)

Klinscek, P

1976-01-01

An investigation was carried out to establish the changes in the lead content of trees and shrubs on the Margaret island in Budapest as a response to the reduction in motor-vehicle traffic introduced in 1974. Compared to samples of the control area (Vacratot) the Margaret island samples were found to have a considerable higher lead content. As a consequence of the traffic modifying measure a 30% decrease in the lead content of the samples was verified. The lead pollution did not involve changes in the chlorophyll content of samples. Accumulation of lead pollution is a specific feature. Lead pollution is accumulated to a great extent (multiple of other plants) by the pilose-leaved CELTIS occidentalis, the pinnate-leaved FRAXINUS angustifolia, ssp. pannonica and the undulate-leaved AESCULUS hippocastanum as well as from among the evergreen by the stellate-hair HEDERA helix. The green belt bordering the roads by its active lead cumulation plays an important role in lessening the plumb pollution of areas more distant from the road. 14 references 3 tables.

Hypocotyl derived in vitro regeneration of pumpkin ash (Fraxinus profunda)

Science.gov (United States)

Micah E. Stevens; Paula M. Pijut

2012-01-01

Pumpkin ash (Fraxinus profunda (Bush) Bush) is at risk for extirpation by an exotic insect, the emerald ash borer (EAB). Pumpkin ash is limited to wetland areas of the Eastern United States, and has been listed as an endangered species because of EAB activity. Pumpkin ash provides many benefits to the ecosystem, and its wood is used in the...

Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle.

Science.gov (United States)

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.

Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle.

Directory of Open Access Journals (Sweden)

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.

Environmental heterogeneity explains the genetic structure of Continental and Mediterranean populations of Fraxinus angustifolia Vahl.

Directory of Open Access Journals (Sweden)

Martina Temunović

Full Text Available Tree species with wide distributions often exhibit different levels of genetic structuring correlated to their environment. However, understanding how environmental heterogeneity influences genetic variation is difficult because the effects of gene flow, drift and selection are confounded. We investigated the genetic variation and its ecological correlates in a wind-pollinated Mediterranean tree species, Fraxinus angustifolia Vahl, within a recognised glacial refugium in Croatia. We sampled 11 populations from environmentally divergent habitats within the Continental and Mediterranean biogeographical regions. We combined genetic data analyses based on nuclear microsatellite loci, multivariate statistics on environmental data and ecological niche modelling (ENM. We identified a geographic structure with a high genetic diversity and low differentiation in the Continental region, which contrasted with the significantly lower genetic diversity and higher population divergence in the Mediterranean region. The positive and significant correlation between environmental and genetic distances after controlling for geographic distance suggests an important influence of ecological divergence of the sites in shaping genetic variation. The ENM provided support for niche differentiation between the populations from the Continental and Mediterranean regions, suggesting that contemporary populations may represent two divergent ecotypes. Ecotype differentiation was also supported by multivariate environmental and genetic distance analyses. Our results suggest that despite extensive gene flow in continental areas, long-term stability of heterogeneous environments have likely promoted genetic divergence of ashes in this region and can explain the present-day genetic variation patterns of these ancient populations.

Genetic transformation of Fraxinus spp. for resistance to the emerald ash borer

Science.gov (United States)

Paula M. Pijut; Rochelle R. Beasley; Kaitlin J. Palla

2010-01-01

The emerald ash borer (EAB; Agrilus planipennis Fairmaire) (Coleoptera; Buprestidae) is a wood-boring beetle that poses substantial risk to the ash resource in North America. Ash species native to the United States and known to be susceptible to EAB are Fraxinus pennsylvanica (green ash), F. americana (white ash...

Development of Ash Dieback in South-Eastern Germany and the Increasing Occurrence of Secondary Pathogens

Directory of Open Access Journals (Sweden)

Heike D. Lenz

2016-02-01

Full Text Available Since its first identification in Poland in 2006, the ascomycete Hymenoscyphus fraxineus has caused massive dieback of Fraxinus excelsior in the countries of eastern, northern and central Europe. This work shows the development, expansion, and severity of the disease in south-eastern Germany for a period of four years, starting in 2010. Differences between habitats, as well as age classes have been captured. The presence and the amount of potentially resistant trees were proven over the years, to determine how high the resistance level might be. Typical disease symptoms are the wilting of leaves, necrotic lesions in the bark and reddish discolorations of branches and stems. In addition, stem necroses also appear by infection with species of Armillaria. Therefore, special attention has been given to Armillaria species in affected ash stands but also to other secondary pathogens, like ash bark beetles. It is shown that breeding galleries of Hylesinus fraxini are only found in trees that have recently died and thus Hylesinus fraxini is still acting as a secondary opportunistic pathogen. In contrast, Armillaria spp. can be considered as serious pathogens of weakened ash trees. In different ash stands, typical symptoms of infection can be found. A relationship between stem base necrotic lesions and vitality was examined. It is shown that necrotic lesions severely contribute to accelerating the mortality of ash trees. In addition to the high infection pressure by H. fraxineus, the high inoculum of Armillaria in the soil facilitates further infections and, thus, likewise endangers the survival of potentially resistant trees. In the following years, forest conversion and seed harvest in affected ash stands will have to be urgently considered to avoid tree gaps on a large scale. Furthermore, infection assays of potentially resistant trees with ensuing breeding programmes should be initially started for the conservation of this ecologically and

Sap flow of black ash in wetland forests of northern Minnesota, USA: Hydrologic implications of tree mortality due to emerald ash borer

Science.gov (United States)

Andrew C. Telander; Robert A. Slesak; Anthony W. D' Amato; Brian J. Palik; Kenneth N. Brooks; Christian F. Lenhart

2015-01-01

Black ash (Fraxinus nigra) mortality caused by the invasive emerald ash borer (EAB) is of concern to land managers in the upper Great Lakes region, given the large areas of ash-dominated forest and potential alteration of wetland hydrology following loss of this foundation tree species. The importance of changes in evapotranspiration (ET) following...

Establishment of trees on minesoils during drought and wet years

International Nuclear Information System (INIS)

Larson, M.M.; Kost, D.A.; Vimmerstedt, J.P.

1995-01-01

In two studies, green ash (Fraxinus pennsylvania) and white pine (Pinus strobus) were planted on three minesoils (graded topsoil, ripped topsoil, and gray cast overburden). Mixtures of grasses and/or legumes were seeded at different times in relation to tree planting. In the first study, tree planting was followed by several week of drought; in the second, precipitation was above average for the first two growing seasons following planting. In the drought year, survival of green ash was influenced by minesoil type, herbaceous mixture, and herbaceous seeding time in relation to tree planting. Among minesoils, mean survival was highest (87%) on cast overburden. Seeding grasses the fall before planting resulted in poor ash survival (40% to 47%) compared with seeding at time of planting (82% to 85%). Ash survived well (81% to 94%) on legume-seeded plots. When tree planting was followed by two wet seasons, survival at 4 and 5 yr ranged from very good to excellent in all treatments. Total height of ash trees on cast overburden averaged 31% less than that of trees on topsoil, and 29% greater on legume-seeded subplots than trees on grass subplots, although herbaceous biomass was greater on legume subplots. The three minesoils proved unsuitable for white pine. 17 refs., 7 tabs

Intraspecific variation in Fraxinus pennsylvanica responses to emerald ash borer (Agrilus planipennis)

Science.gov (United States)

J.L. Koch; D.W. Carey; M.E. Mason; T.M. Poland; K.S. Knight

2015-01-01

The emerald ash borer (EAB; Agrilus planipennis Fairmaire) is a bark and wood boring beetle native to east Asia that was first discovered in North America in 2002. Since then, entire stands of highly susceptible green ash (Fraxinus pennsylvanica Marshall) have been killed within a few years of infestation. We have identified a...

Lethal trap trees: a potential option for emerald ash borer (Agrilus planipennis Fairmaire) management.

Science.gov (United States)

McCullough, Deborah G; Poland, Therese M; Lewis, Phillip A

2016-05-01

Economic and ecological impacts of ash (Fraxinus spp.) mortality resulting from emerald ash borer (EAB) (Agrilus planipennis Fairmaire) invasion are severe in forested, residential and urban areas. Management options include girdling ash trees to attract ovipositing adult beetles and then destroying infested trees before larvae develop or protecting ash with a highly effective, systemic emamectin benzoate insecticide. Injecting this insecticide and then girdling injected trees a few weeks later could effectively create lethal trap trees, similar to a bait-and-kill tactic, if girdling does not interfere with insecticide translocation. We compared EAB larval densities on girdled trees, trees injected with the emamectin benzoate insecticide, trees injected with the insecticide and then girdled 18-21 days later and untreated controls at multiple sites. Pretreatment larval densities did not differ among treatments. Current-year larval densities were higher on girdled and control trees than on any trees treated with insecticide at all sites. Foliar residue analysis and adult EAB bioassays showed that girdling trees after insecticide injections did not reduce insecticide translocation. Girdling ash trees to attract adult EAB did not reduce efficacy of emamectin benzoate trunk injections applied ≥ 18 days earlier and could potentially be used in integrated management programs to slow EAB population growth. © 2015 Society of Chemical Industry.

Influence of hydrologic modifications on Fraxinus pennsylvanica in the Mississippi River Alluvial Valley, USA

Science.gov (United States)

Gee, Hugo K.W.; King, Sammy L.; Keim, Richard F.

2015-01-01

We used tree-ring analysis to examine radial growth response of a common, moderately flood-tolerant species (Fraxinus pennsylvanica Marshall) to hydrologic and climatic variability for > 40 years before and after hydrologic modifications affecting two forest stands in the Mississippi River Alluvial Valley (USA): a stand without levees below dams and a stand within a ring levee. At the stand without levees below dams, spring flood stages decreased and overall growth increased after dam construction, which we attribute to a reduction in flood stress. At the stand within a ring levee, growth responded to the elimination of overbank flooding by shifting from being positively correlated with river stage to not being correlated with river stage. In general, growth in swales was positively correlated with river stage and Palmer Drought Severity Index (an index of soil moisture) for longer periods than flats. Growth decreased after levee construction, but swales were less impacted than flats likely because of differences in elevation and soils provide higher soil moisture. Results of this study indicate that broad-scale hydrologic processes differ in their effects on the flood regime, and the effects on growth of moderately flood-tolerant species such as F. pennsylvanica can be mediated by local-scale factors such as topographic position, which affects soil moisture.

Enhancement of phloem exudation from Fraxinus uhdei Wenz. (evergreen ash) using ethylenediaminetetraacetic acid

International Nuclear Information System (INIS)

Costello, L.R.; Bassham, J.A.; Calvin, M.

1982-01-01

Ethylenediaminetetraacetic acid (EDTA) enhanced the exudation of 14 C-labeled assimilates from excised leaflets and whole plant specimens of Fraxinus uhdei Wenz. A 2 millimolar EDTA concentration was found to be most effective in promoting exudation from excised leaflets, while 10 millimolar EDTA was most effective in whole plants experiments. Exudation rate reached a maximum after 24 hours in both experiments. The continuous presence of EDTA throughout the treatment period was required for maximum exudation from excised leaflets. Stachyose, raffinose, verbascose, and sucrose were the principal compounds found to occur in exudate samples. These compounds are typically transported in sieve elements of various Fraxinus species suggesting the exudate was of phloem orgin. Electron microscope studies of petiolule sieve plate pores from excisd leaflets showed substantially less callose appearing after treatment with EDTA than after H 2 O treatment. It is suggested that EDTA enhances phloem exudation by inhibiting or reducing callose formation in sieve plate pores. The exudation enhancement technique described for whole plant specimens is suggested as a useful means of collecting phloem sap and studying translocation in woody plants

Is bark pH more important than tree species in determining the composition of nitrophytic or acidophytic lichen floras?

Energy Technology Data Exchange (ETDEWEB)

Spier, L. [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands); Dobben, H. van, E-mail: han.vandobben@wur.n [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands); Dort, K. van [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands)

2010-12-15

To study the pH preference of epiphytic lichens, the bark pH of Fraxinus, Tilia, Quercus and Ulmus trees in an urban environment was measured using a flat surface electrode. The total number of trees was 253. A survey was made of the lichens in a 40 x 40 cm quadrat surrounding the pH measurement point. Our data analysis using multivariate and univariate statistical techniques indicates that the tree species is the most important factor influencing lichen colonisation, and that bark pH alone is of less importance. We hypothesize that the changed pollution climate, with strong decreases in both sulphur dioxide and ammonia concentrations over the past two decades and a concomitant general increase in bark pH, has made epiphytes less sensitive to pH. - Tree species, rather than bark pH determines the occurrence of acidophytes and nitrophytes on trees.

Stenhammer, Wilhelm. sinfonien Nr. 1 F-Dur und Nr. 2 g-Moll op. 34, Excelsior! op. 13, Serenade F-Dur op. 31. Sinfonieorchester Göteborg, Neeme Järvi / Andreas K. W. Meyer

Index Scriptorium Estoniae

Meyer, Andreas K. W.

1995-01-01

Uuest heliplaadist "Stenhammer, Wilhelm. sinfonien Nr. 1 F-Dur und Nr. 2 g-Moll op. 34, Excelsior! op. 13, Serenade F-Dur op. 31. Sinfonieorchester Göteborg, Neeme Järvi". DG 2 CD 445857-2 (WD: 138'37")

Airborne pollen of Carya, Celtis, Cupressus, Fraxinus and Pinus in the metropolitan area of Monterrey Nuevo Leon, Mexico.

Science.gov (United States)

Rocha-Estrada, Alejandra; Alvarado-Vázquez, Marco Antonio; Torres-Cepeda, Teresa Elizabeth; Foroughbakhch-Pournavab, Rahim; Hernández-Piñero, Jorge Luis

2008-01-01

The concentration of pollen grains in the atmosphere over the metropolitan area of Monterrey, Nuevo Leon, Mexico, was analyzed throughout a year from March 2003-February 2004, focused on the genus Carya, Celtis, Cupressus, Fraxinus and Pinus owing to their interest as etiological pollinosis agents in diverse regions of the world. A 7-day Hirst type volumetric spore and pollen trap was located on a building roof of the city at 15 m from ground level for continuous sampling. The total quantity of pollen recorded for the study period was 21,083 grains/m(3), corresponding to 49.75 % of the taxa of interest. February and March were the months with higher pollen amounts in the air with 7,525 and 2,781 grains/m(3), respectively, and amounted to 49 % of total year through pollen. Fraxinus was the genus which contributed to the largest amount of pollen with 28 % of total grains (5,935 grains/m(3)) followed by Cupressus with 13 % (2,742 grains/ m(3)). Celtis, Pinus and Carya contributed with 5.3 % , 2.7 % , and 0.6 % of total pollen, respectively. These results indicate that Fraxinus and Cupressus are present in the area in sufficient quantity to indicate likely involvement in the origin of allergic disorders in the human population.

Genetic variation in dieback resistance in Fraxinus excelsior confirmed by progeny inoculation assay

DEFF Research Database (Denmark)

Lobo, Albin; McKinney, Lea Vig; Hansen, Jon Kehlet

2015-01-01

from low susceptible mother clones developed smaller necroses when compared to offspring from susceptible clones. Their crown damage due to natural infections was also significantly less. The correlation coefficient between average crown damages of mother clones and the average of their progeny was 0...

Targeted and Untargeted Metabolomics to Explore the Bioavailability of the Secoiridoids from a Seed/Fruit Extract (Fraxinus angustifolia Vahl in Human Healthy Volunteers: A Preliminary Study

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Rocío García-Villalba

2015-12-01

Full Text Available The bark, seeds, fruits and leaves of the genus Fraxinus (Oleaceae which contain a wide range of phytochemicals, mostly secoiridoid glucosides, have been widely used in folk medicine against a number of ailments, yet little is known about the metabolism and uptake of the major Fraxinus components. The aim of this work was to advance in the knowledge on the bioavailability of the secoiridoids present in a Fraxinus angustifolia Vahl seed/fruit extract using both targeted and untargeted metabolomic analyses. Plasma and urine samples from nine healthy volunteers were taken at specific time intervals following the intake of the extract and analyzed by UPLC-ESI-QTOF. Predicted metabolites such as tyrosol and ligstroside-aglycone glucuronides and sulfates were detected at low intensity. These compounds reached peak plasma levels 2 h after the intake and exhibited high variability among the participants. The ligstroside-aglycone conjugates may be considered as potential biomarkers of the Fraxinus secoiridoids intake. Using the untargeted approach we additionally detected phenolic conjugates identified as ferulic acid and caffeic acid sulfates, as well as hydroxybenzyl and hydroxyphenylacetaldehyde sulfate derivatives which support further metabolism of the secoiridoids by phase I and (or microbial enzymes. Overall, the results of this study suggest low uptake of intact secoiridoids from a Fraxinus angustifolia Vahl extract in healthy human volunteers and metabolic conversion by esterases, glycosidases, and phase II sulfo- and glucuronosyl transferases to form smaller conjugated derivatives.

Flash-flood impacts cause changes in wood anatomy of Alnus glutinosa, Fraxinus angustifolia and Quercus pyrenaica.

Science.gov (United States)

Ballesteros, J A; Stoffel, M; Bollschweiler, M; Bodoque, J M; Díez-Herrero, A

2010-06-01

Flash floods may influence the development of trees growing on channel bars and floodplains. In this study, we analyze and quantify anatomical reactions to wounding in diffuse-porous (Alnus glutinosa L.) and ring-porous (Fraxinus angustifolia Vahl. and Quercus pyrenaica Willd.) trees in a Mediterranean environment. A total of 54 cross-sections and wedges were collected from trees that had been injured by past flash floods. From each of the samples, micro-sections were prepared at a tangential distance of 1.5 cm from the injury to determine wounding-related changes in radial width, tangential width and lumen of earlywood vessels, and fibers and parenchyma cells (FPC). In diffuse-porous A. glutinosa, the lumen area of vessels shows a significant (non-parametric test, P-value <0.05) decrease by almost 39% after wounding. For ring-porous F. angustifolia and Q. pyrenaica, significant decreases in vessel lumen area are observed as well by 59 and 42%, respectively. Radial width of vessels was generally more sensitive to the decrease than tangential width, but statistically significant values were only observed in F. angustifolia. Changes in the dimensions of earlywood FPC largely differed between species. While in ring-porous F. angustifolia and Q. pyrenaica the lumen of FPC dropped by 22 and 34% after wounding, we observed an increase in FPC lumen area in diffuse-porous A. glutinosa of approximately 35%. Our data clearly show that A. glutinosa represents a valuable species for flash-flood research in vulnerable Mediterranean environments. For this species, it will be possible in the future to gather information on past flash floods with non-destructive sampling based on increment cores. In ring-porous F. angustifolia and Q. pyrenaica, flash floods leave less drastic, yet still recognizable, signatures of flash-flood activity through significant changes in vessel lumen area. In contrast, the use of changes in FPC dimensions appears less feasible for the determination of

Biomass models to estimate carbon stocks for hardwood tree species

Energy Technology Data Exchange (ETDEWEB)

Ruiz-Peinado, R.; Montero, G.; Rio, M. del

2012-11-01

To estimate forest carbon pools from forest inventories it is necessary to have biomass models or biomass expansion factors. In this study, tree biomass models were developed for the main hardwood forest species in Spain: Alnus glutinosa, Castanea sativa, Ceratonia siliqua, Eucalyptus globulus, Fagus sylvatica, Fraxinus angustifolia, Olea europaea var. sylvestris, Populus x euramericana, Quercus canariensis, Quercus faginea, Quercus ilex, Quercus pyrenaica and Quercus suber. Different tree biomass components were considered: stem with bark, branches of different sizes, above and belowground biomass. For each species, a system of equations was fitted using seemingly unrelated regression, fulfilling the additivity property between biomass components. Diameter and total height were explored as independent variables. All models included tree diameter whereas for the majority of species, total height was only considered in the stem biomass models and in some of the branch models. The comparison of the new biomass models with previous models fitted separately for each tree component indicated an improvement in the accuracy of the models. A mean reduction of 20% in the root mean square error and a mean increase in the model efficiency of 7% in comparison with recently published models. So, the fitted models allow estimating more accurately the biomass stock in hardwood species from the Spanish National Forest Inventory data. (Author) 45 refs.

Similar Gender Dimorphism in the Costs of Reproduction across the Geographic Range of Fraxinus ornus

Science.gov (United States)

Verdú, Miguel; Spanos, Kostas; čaňová, Ingrid; Slobodník, Branko; Paule, Ladislav

2007-01-01

Background and Aims The reproductive costs for individuals with the female function have been hypothesized to be greater than for those with the male function because the allocation unit per female flower is very high due to the necessity to nurture the embryos until seed dispersal occurs, while the male reproductive allocation per flower is lower because it finishes once pollen is shed. Consequently, males may invest more resources in growth than females. This prediction was tested across a wide geographical range in a tree with a dimorphic breeding system (Fraxinus ornus) consisting of males and hermaphrodites functioning as females. The contrasting ecological conditions found across the geographical range allowed the evaluation of the hypothesis that the reproductive costs of sexual dimorphism varies with environmental stressors. Methods By using random-effects meta-analysis, the differences in the reproductive and vegetative investment of male and hermaphrodite trees of F. ornus were analysed in 10 populations from the northern (Slovakia), south-eastern (Greece) and south-western (Spain) limits of its European distribution. The variation in gender-dimorphism with environmental stress was analysed by running a meta-regression between these effect sizes and the two environmental stress indicators: one related to temperature (the frost-free period) and another related to water availability (moisture deficit). Key Results Most of the effect sizes showed that males produced more flowers and grew more quickly than hermaphrodites. Gender differences in reproduction and growth were not minimized or maximized under adverse climatic conditions such as short frost-free periods or severe aridity. Conclusions The lower costs of reproduction for F. ornus males allow them to grow more quickly than hermaphrodites, although such differences in sex-specific reproductive costs are not magnified under stressful conditions. PMID:17098751

Acer-Fraxinus dominated woods of the Italian peninsula: a floristic and phytogeographical analysis

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Claudia Angiolini

2012-07-01

Full Text Available Forest communities dominated by noble broad-leaved trees (maple, lime and ash in Europe are of elevated scientific and con­servation interest for the European Union. In this paper, we first present a synthesis of the maple and ash forests in peninsular Italy. By classifying these forests, we distinguish seven main groups for the territory, which only broadly match the syntaxa proposed in the literature. The variability of the Apennine data is then analysed floristically and phytogeographically (using chorological components in a central-southern European context, using numerical classification, INSPAN, and direct ordination of several synoptic tables. These analyses allow us to identify six different groups of European Acer-Fraxinus communities. Canonical Vari­ates Analysis (CVA of the geographical components confirms the existence of distinct phytogeographical groups. In particular, we highlight the clear distinction between central European (including the Alps and southern European coenoses. Among the latter there was a clear floristic and chorological distinction between Balkan and Apennine groups. These results reflect the biogeographical subdivisions of Europe, but do not support the syntaxonomical schemes proposed by other authors, which are based only on floristic-ecological information or (recently use a smaller data set of Italian relevés. This study also shows that syntaxonomical schemes above the association level should pay more attention to phytogeographical aspects rather than focus on floristic-ecological information alone, in order to propose models that are of value on a geographical scale.

Monitoring ash (Fraxinus spp.) decline and emerald ash borer (Agrilus planipennis) symptoms in infested areas

Science.gov (United States)

Kathleen S. Knight; Britton P. Flash; Rachel H. Kappler; Joel A. Throckmorton; Bernadette Grafton; Charles E. Flower

2014-01-01

Emerald ash borer (A. planipennis) (EAB) has had a devastating effect on ash (Fraxinus) species since its introduction to North America and has resulted in altered ecological processes across the area of infestation. Monitoring is an important tool for understanding and managing the impact of this threat, and the use of common...

Results of the radiological survey of the Excelsior Steel Ball Company, Tonawanda, New York (TNY005)

International Nuclear Information System (INIS)

McKenzie, S.P.; Brown, K.S.

1998-07-01

At the request of the US Department of Energy (DOE), a team from Oak Ridge National Laboratory conducted two radiological surveys of property belonging to the Excelsior Steel Ball Company, which is surrounded on three sides by the former site of the Linde Uranium Refinery, Tonawanda, New York. The surveys were performed in September 1997 and February 1998. The purpose of the first survey was to determine if radioactive residuals were present from previous activities at the former Linde site. The Linde Air Products Division of Union Carbide Corporation, Tonawanda, New York, had used radioactive materials at that location for work performed under government contract from 1942 through 1948. The purpose of the second survey was to collect additional biased samples from an area of the site where biased sample results showed slightly elevated levels of thorium-232

Hepatoprotective standardized EtOH–water extract from the seeds of Fraxinus rhynchophylla Hance

OpenAIRE

Guo, Sen; Guo, Tiantian; Cheng, Ni; Liu, Qingchao; Zhang, Yunting; Bai, Lu; Zhang, Li; Cao, Wei; Ho, Chi-Tang; Bai, Naisheng

2016-01-01

Fraxinus rhynchophylla Hance (Oleaceae), its stem barks are known as Cortex fraxini (?? q?n p?) listed in Chinese Pharmacopoeia. Phytochemical study has indicated that methanol extracts from Qinpi has protective effect on acute liver injury. The present study investigates the hepatoprotective activity of EtOH?water extract from the seeds of F.?rhynchophylla Hance against carbon tetrachloride-induced liver injury in mice. The EtOH?water extract significantly alleviated liver damage as indicate...

Population Dynamic, the Spatial Distribution Pattern and Management of Ash Tree, Fraxinus rotundifolia psyllid Psyllopsis discrepans Flor (Hem., Psyllidae in Kermanshah Province, Iran

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arezoo jamshidi

2017-03-01

Full Text Available Introduction: Due to increasing air pollution, one of the ways to reduce pollution is to develop the green space, the urban parks, domestic gardens and streets marginal, including the ash trees, which play a vital role in supporting urban by its beauty and reducing air pollution. One of the convenient options to overshadow ash trees in their gardens. The jumping plant-louse, Psyllopsis discrepans is a sap-suckerpest which has highly host -specific and feed mainly on the young leaves and sprouts, is considered as important ash pests. Large populations of the pest cause the leaf curl gall and distort which result in leaf scar and less aesthetic appearance of ash canopy. The pest causes plant weakness by the toxic action of the saliva injected during their feeding process. The nymphal instar secreted honeydew which stimulates fungal growth on plant organs. There are a number of psyllid control methods which each of them has its own set of advantages and disadvantages. The objective of this work was to verify the population fluctuation and assessing the spatial distribution of P. discrepans, in ash tree, Fraxinus rotundifolia Mill (Oleaceae and in order to develop the best psyllid control plan, it is important that to weigh out the most effective options to reduce the population of this pest, in Kermanshah, western region of Iran. Materials and Methods: In this study the monitoring of P. discrepans population was carried out in urban areas of infested trees, using yellow adhesive traps with 50 m far from each other. Two sampling methods were took place the regular weekly from March 2014 to May 2015. nymphs tend to cling to the foliage when disturbed while the adults tend to jump and fly away. These differences in habit necessitated the use of two sampling techniques. The counts of eggs and nymphs were made by taking samples at each infested tree. The samples were placed individually in plastic bags and chilled in a refrigerator until they could be

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

International Nuclear Information System (INIS)

Baycu, Guelriz; Tolunay, Doganay; Ozden, Hakan; Guenebakan, Suereyya

2006-01-01

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

In vitro inducible nitric oxide synthesis inhibitory active constituents from Fraxinus rhynchophylla.

Science.gov (United States)

Kim, N Y; Pae, H O; Ko, Y S; Yoo, J C; Choi, B M; Jun, C D; Chung, H T; Inagaki, M; Higuchi, R; Kim, Y C

1999-10-01

Bioassay-guided fractionation of an H2O extract of the barks of Fraxinus rhynchophylla has furnished two inducible nitric oxide synthase (iNOS) inhibitory compounds, ferulaldehyde (1) and scopoletin (3) together with a coumarin, fraxidin (2). Compounds 1 and 3 showed inhibition of nitric oxide (NO) synthesis in a dose-dependent manner by murine macrophage-like RAW 264.7 cells stimulated with interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS). The inhibition of NO synthesis of 1 was reflected in the decreased amount of iNOS protein, as determined by Western blotting.

The sentinel tree nursery as an early warning system for pathway risk assessment: Fungal pathogens associated with Chinese woody plants commonly shipped to Europe.

Directory of Open Access Journals (Sweden)

Anna Maria Vettraino

Full Text Available Introduction of and invasion by alien plant pathogens represents the main cause of emerging infectious diseases affecting domesticated and wild plant species worldwide. The trade in living plants is the most common pathway of introduction. Many of the alien tree pathogens recently introduced into Europe were not previously included on any quarantine lists. To help determine the potential risk of pest introduction through trading of ornamental plants, a sentinel nursery was established in Beijing, China in 2008. The sentinel nursery planting included four of the most common ornamental woody species shipped to Europe including Ilex cornuta var. fortunae, Zelkova schneideriana, Fraxinus chinensis and Buxus microphylla. Symptoms developing on these species within the sentinel nursery were detected in 2013 and consisted of necrotic spots on leaves, canker and stem necrosis, shoot blight and shoot necrosis. Fungi associated with the trees and their symptoms included Alternaria alternata detected from all hosts; Diaporthe liquidambaris and Diaporthe capsici from bark and leaf necrosis of Zelkova schneideriana; Botryosphaeria dothidea and Nothophoma quercina from stem cankers on Fraxinus chinensis and leaf necrosis on Ilex cornuta; and Pseudonectria foliicola from leaf necrosis on Buxus microphylla. Next generation sequencing analysis from asymptomatic tissues detected eighteen OTU's at species level among which some taxa had not been previously recorded in Europe. These results clearly demonstrate that looking at trees of internationally traded species in the region of origin can reveal the presence of potentially harmful organisms of major forestry, landscape or crop trees. Results of this study also provide an indication as to how some disease agents can be introduced using pathways other than the co-generic hosts. Hence, sentinel nurseries represent one potential mechanism to address the current lack of knowledge about pests in the countries from

Water-soluble constituents of the root barks of Fraxinus rhynchophylla (Chinese drug Qinpi).

Science.gov (United States)

Xiao, Kai; Song, Qing-Hong; Zhang, Shu-Wei; Xuan, Li-Jiang

2008-01-01

Chemical studies on the roots of Fraxinus rhynchophylla led to the isolation of fraxisecoside (1), a novel coumarin-secoiridoid hybrid glycoside, namely, fraxetin-8-O-[11'-methyl-oleosidyl-(7'-->6'')]-beta-D-glucopyranoside and 14 known compounds. Their structures were elucidated based on chemical evidence and spectroscopic analysis, including extensive 2D NMR methods. Compound 2 was first isolated as a pure compound. Compound 1 exhibited moderate PTP1B inhibition activity. Compounds 1 and 2 showed inhibition activity against B- and T-cell proliferation, without cytotoxicity.

Effectiveness of treatments to establish trees on minelands during drought and wet years

International Nuclear Information System (INIS)

Larson, M.M.; Kost, D.A.; Vimmerstedt, J.P.

1994-01-01

In two studies, green ash (Fraxinus pennsylvanica) and white pine (Pinus strobus) were planted on three minesoils (graded topsoil, ripped topsoil, and gray cast overburden). Mixtures of grasses and/or legumes were seeded at different times in relation to tree planting. In the first study, tree planting was followed by several weeks of drought; in the second study, precipitation was above average for the first two growing seasons following planting. In the drought year, survival of green ash was influenced by minesoil type, herbaceous mixture, and time of seeding in relation to tree planting. Among minesoils, ash survival on ripped topsoil was 28% above that on graded topsoil in one seeding treatment, but mean survival was highest (87%) on cast overburden. Seeding grasses the fall before planting resulted in poor ash survival (40% to 47%) compared with seeding at time of planting (82% to 85%). Ash survived well (81% to 94%) on legume-seeded plots owing, in part, to slow early development of legumes the first season. When tree planting was followed by two wet seasons, survival at 4 and 5 yr ranged from very good to excellent, with much smaller differences between treatments. Total height of ash trees on cast overburden averaged 31% less than that of trees on topsoil. Mean height of ash on legume-seeded subplots was 75 cm, compared with 58 cm on grass subplots, although herbaceous biomass was greater on legume subplots. The three minesoils proved unsuitable for white pine

Effects of Reforestation on Tree Pollen Sensitization in Inhabitants of Nuevo Leon, Mexico

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Samuel Palma-Gómez

2014-06-01

Full Text Available Background: Climate change has implications for health, ecology and society. Urban green areas are a key element in the planning of citie, promoting citizen interaction with the environment, as well as health. Lack of planning and design of these areas as well as the selection of ornamental trees can be a trigger of pollen allergy in the surrounding population. Reforestation is among the programs implemented by the government that have an impact on allergy. Environmental reforestation programs do not take into account the allergenic potential of some spe- cies. In the last 4 years, the government of Nuevo Leon, Mexico, has planted nearly 18,000 Quercus species trees, in addition to an unknown number of Fraxinus species trees that are listed as tree species with high pollen production. Objective: To identify changes in tree pollen sensitization, based on environmental reforestation programs. Material and method: A retrospective and descriptive study was done in which positive skin prick tests to pollen from trees in the interval of 2010-2014 were analyzed, correlating between tree species used for reforestation and increased sensitivity to the former. Results: A statistically signi cant increase in pollen sensitization to species with which Nuevo Leon was reforested was found, along with a decrease in sensitization to the species that were not reforested. Conclusion: Reforestation contributes to some extent to the change in the pattern of positive skin tests and may result in more frequent exac- erbations of respiratory diseases. It is an activity that should always be regulated and assisted by experts in the according eld.

[Effects of reforestation on tree pollen sensitization in inhabitants of Nuevo Leon, Mexico].

Science.gov (United States)

Palma-Gómez, Samuel; González-Díaz, Sandra Nora; Arias-Cruz, Alfredo; Macías-Weinmann, Alejandra; Amaro-Vivian, Laura Elizabeth; Pérez-Vanzzini, Rafael; Gutiérrez-Mujica, José Julio; Yong-Rodríguez, Adrián

2014-01-01

Climate change has implications for health, ecology and society. Urban green areas are a key element in the planning of cities, promoting citizen interaction with the environment, as well as health. Lack of planning and design of these areas as well as the selection of ornamental trees can be a trigger of pollen allergy in the surrounding population. Reforestation is among the programs implemented by the government that have an impact on allergy. Environmental reforestation programs do not take into account the allergenic potential of some species. In the last 4 years, the government of Nuevo Leon, Mexico, has planted nearly 18,000 Quercus species trees, in addition to an unknown number of Fraxinus species trees that are listed as tree species with high pollen production. To identify changes in tree pollen sensitization, based on environmental reforestation programs. A retrospective and descriptive study was done in which positive skin prick tests to pollen from trees in the interval of 2010-2014 were analyzed, correlating between tree species used for reforestation and increased sensitivity to the former. A statistically significant increase in pollen sensitization to species with which Nuevo Leon was reforested was found, along with a decrease in sensitization to the species that were not reforested. Reforestation contributes to some extent to the change in the pattern of positive skin tests and may result in more frequent exacerbations of respiratory diseases. It is an activity that should always be regulated and assisted by experts in the according field.

Relationships between root respiration rate and root morphology, chemistry and anatomy in Larix gmelinii and Fraxinus mandshurica.

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Jia, Shuxia; McLaughlin, Neil B; Gu, Jiacun; Li, Xingpeng; Wang, Zhengquan

2013-06-01

Tree roots are highly heterogeneous in form and function. Previous studies revealed that fine root respiration was related to root morphology, tissue nitrogen (N) concentration and temperature, and varied with both soil depth and season. The underlying mechanisms governing the relationship between root respiration and root morphology, chemistry and anatomy along the root branch order have not been addressed. Here, we examined these relationships of the first- to fifth-order roots for near surface roots (0-10 cm) of 22-year-old larch (Larix gmelinii L.) and ash (Fraxinus mandshurica L.) plantations. Root respiration rate at 18 °C was measured by gas phase O2 electrodes across the first five branching order roots (the distal roots numbered as first order) at three times of the year. Root parameters of root diameter, specific root length (SRL), tissue N concentration, total non-structural carbohydrates (starch and soluble sugar) concentration (TNC), cortical thickness and stele diameter were also measured concurrently. With increasing root order, root diameter, TNC and the ratio of root TNC to tissue N concentration increased, while the SRL, tissue N concentration and cortical proportion decreased. Root respiration rate also monotonically decreased with increasing root order in both species. Cortical tissue (including exodermis, cortical parenchyma and endodermis) was present in the first three order roots, and cross sections of the cortex for the first-order root accounted for 68% (larch) and 86% (ash) of the total cross section of the root. Root respiration was closely related to root traits such as diameter, SRL, tissue N concentration, root TNC : tissue N ratio and stele-to-root diameter proportion among the first five orders, which explained up to 81-94% of variation in the rate of root respiration for larch and up to 83-93% for ash. These results suggest that the systematic variations of root respiration rate within tree fine root system are possibly due to the

Ozone air pollution and foliar injury development on native plants of Switzerland

International Nuclear Information System (INIS)

Novak, Kristopher; Skelly, John M.; Schaub, Marcus; Kraeuchi, Norbert; Hug, Christian; Landolt, Werner; Bleuler, Peter

2003-01-01

Visible ozone-induced foliar injury on native forest species of Switzerland was identified and confirmed under ambient OTC-conditions and related to the current European AOT40 standard. - The objectives of this study were to examine the foliar sensitivity to ozone exposure of 12 tree, shrub, and herbaceous species native to southern Switzerland and determine the seasonal cumulative ozone exposures required to induce visible foliar injury. The study was conducted from the beginning of May through the end of August during 2000 and 2001 using an open-top chamber research facility located within the Lattecaldo Cantonal Forest Nursery in Canton Ticino, southern Switzerland (600 m asl). Plants were examined daily and dates of initial foliar injury were recorded in order to determine the cumulative AOT40 ppb h ozone exposure required to cause visible foliar injury. Plant responses to ozone varied significantly among species; 11 species exhibited visible symptoms typical of exposures to ambient ozone. The symptomatic species (from most to least sensitive) were Populus nigra, Viburnum lantana, Salix alba, Crataegus monogyna, Viburnum opulus, Tilia platyphyllos, Cornus alba, Prunus avium, Fraxinus excelsior, Ribes alpinum, and Tilia cordata; Clematis spp. did not show foliar symptoms. Of the 11 symptomatic species, five showed initial injury below the critical level AOT40 10 ppmh O 3 in the 2001 season

Evaluation of urban environment pollution based on the accumulation of macro- and trace elements in epiphytic lichens.

Science.gov (United States)

Parzych, Agnieszka; Astel, Aleksander; Zduńczyk, Anna; Surowiec, Tomasz

2016-01-01

Nitrogen, phosphorus, potassium, magnesium, zinc, nickel, copper, manganese, iron and lead accumulation properties of three epiphytic lichen species (Hypogymnia physodes (L.) Nyl., Parmelia sulcata Taylor and Xanthoria parietina (L.) Th. Fr.) were compared. An assessment of pollution of the municipal environment in Słupsk (Poland) according to macro- and trace elements was also done. Lichen samples were taken in Autumn 2013 from Betula pendula, Fraxinus excelsior, Acer platanoides, A. pseudoplatanus and Populus sp. trees. Sampling stations comprised of house development areas, green urban parks, vicinity of streets with heavy traffic and industrial enterprises. It was found that lichens represent diverse accumulation properties to pollutants according to the species. X. parietina indicated the highest bioaccumulation in relation to N, K, Mg, Zn and Fe, the thalli of H. physodes accumulated the largest amounts of Ni and Pb, while P. sulcata P and Cu. Manganese was accumulated in similar quantities by all species. Evidences acquired by the use of factor analysis proved that pollution in Słupsk municipal environment is a serious issue with three major sources domination: street dust, marine factor and residual oil combustion. The high-risk areas were detected and visualized using surface maps based on Kriging algorithm. It was seen that the highest pollution occurs in the town centre, while the smallest happened on its outskirts and in urban parks.

Remote sensing of changes in morphology and physiology of trees under stress

Science.gov (United States)

Olson, C. E., Jr.; Rohde, W. G.; Ward, J. M.

1970-01-01

Results of continuing studies of forest trees subjected to varying types of stress are reported. Both greenhouse and field studies are included. Greenhouse work with tree seedlings exposed to varying levels of NaCl and CaCl2 in the soil indicated that, in the initial stages, palisade cells shrink and the amount of air space in the leaf increases. As the severity of damage increases, the cells of the spongy mesophyll shrink and flatten, and the amount of air space in the leaf decreases. Statistical analysis of foliar reflectance and associated moisture content data led to a series of regression equations for predicting foliar moisture content from reflectance data. Equations were calculated for three species, yellow birch (Betula alleghaniensis Britton), sugar maple (Acer saccharum Marsh.) and white ash (Fraxinus americana L.) having multiple correlation coefficients of 0.98, 0.94 and 0.93 respectively. Interpretation of multispectral imagery of the Ann Arbor Forestry Test Site (NASA Site 190) provided evidence that infections of Fomes annosus can be detected in the early stages. Infections of two needle cast diseases were also detected in conifer plantations in the test site. A study of automatic interpretation of multispectral scanner imagery for tree species recognition provided encouraging results.

Radiosensitivity and recovery of tree crowns in a gamma-irradiated northern forest community

International Nuclear Information System (INIS)

Buech, R.R.

1977-01-01

Crown mortality was observed on 13 tree species in a gamma-irradiated forest community located near Rhinelander, Wis. Observations at the end of the first (1973) and second (1974) postirradiation growing seasons are presented for each species. Crown mortality was most severe during 1973 for Acer rubrum, A. saccharum, Ostrya virginiana, Populus tremuloides, Prunus serotina, Quercus rubra, and Ulmus americana. For some species, however, crown mortality was most severe during 1974. These were Betula alleghaniensis, B. papyrifera, Tilia americana, and possibly Fraxinus americana and F. nigra. These differences in year of primary response are explained on the basis of bud differentiation and mortality. The most resistant species were A. saccharum, O. virginiana, and Populus tremuloides, and the most sensitive were T. americana and U. americana. Others were intermediate in sensitivity. Taken collectively, exposures less than 2 or 3 kr did not seriously affect crowns of most species, whereas exposures exceeding about 40 kr were lethal to the crowns of all tree species. The observed zonation of tree mortality closely approximated predictions published by others except for underestimating the resistance of A. saccharum and overestimating the resistance of T. americana, F. americana, and Prunus serotina. Not surprisingly, the tree stratum of the northern forest community was found to be more radiosensitive than lichen, grassland, or herbaceous communities in other irradiation studies

Allometric biomass equations for 12 tree species in coniferous and broadleaved mixed forests, Northeastern China.

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He, Huaijiang; Zhang, Chunyu; Zhao, Xiuhai; Fousseni, Folega; Wang, Jinsong; Dai, Haijun; Yang, Song; Zuo, Qiang

2018-01-01

Understanding forest carbon budget and dynamics for sustainable resource management and ecosystem functions requires quantification of above- and below-ground biomass at individual tree species and stand levels. In this study, a total of 122 trees (9-12 per species) were destructively sampled to determine above- and below-ground biomass of 12 tree species (Acer mandshuricum, Acer mono, Betula platyphylla, Carpinus cordata, Fraxinus mandshurica, Juglans mandshurica, Maackia amurensis, P. koraiensis, Populus ussuriensis, Quercus mongolica, Tilia amurensis and Ulmus japonica) in coniferous and broadleaved mixed forests of Northeastern China, an area of the largest natural forest in the country. Biomass allocation was examined and biomass models were developed using diameter as independent variable for individual tree species and all species combined. The results showed that the largest biomass allocation of all species combined was on stems (57.1%), followed by coarse root (21.3%), branch (18.7%), and foliage (2.9%). The log-transformed model was statistically significant for all biomass components, although predicting power was higher for species-specific models than for all species combined, general biomass models, and higher for stems, roots, above-ground biomass, and total tree biomass than for branch and foliage biomass. These findings supplement the previous studies on this forest type by additional sample trees, species and locations, and support biomass research on forest carbon budget and dynamics by management activities such as thinning and harvesting in the northeastern part of China.

Risk to ash from emerald ash borer: can biological control prevent the loss of ash stands?

Science.gov (United States)

Jian J. Duan; Roy G. Van Driesche; Leah S. Bauer; Daniel M. Kashian; Daniel A. Herms

2015-01-01

Ash trees (Fraxinus spp.) are an important components of both natural forests and urban plantings in the United States and Canada (Federal Register, 2003; Nowak et al., 2003). There are approximately 16 species of Fraxinus native to North America (Harlow et al., 1996; USGS, 2014), each adapted to different ecological niches across...

Progress and Challenges of Protecting North American Ash Trees from the Emerald Ash Borer Using Biological Control

Directory of Open Access Journals (Sweden)

Jian J. Duan

2018-03-01

Full Text Available After emerald ash borer (EAB, Agrilus planipennis Fairmaire, was discovered in the United States, a classical biological control program was initiated against this destructive pest of ash trees (Fraxinus spp.. This biocontrol program began in 2007 after federal regulatory agencies and the state of Michigan approved release of three EAB parasitoid species from China: Tetrastichus planipennisi Yang (Eulophidae, Spathius agrili Yang (Braconidae, and Oobius agrili Zhang and Huang (Encyrtidae. A fourth EAB parasitoid, Spathius galinae Belokobylskij (Braconidae from Russia, was approved for release in 2015. We review the rationale and ecological premises of the EAB biocontrol program, and then report on progress in North American ash recovery in southern Michigan, where the parasitoids were first released. We also identify challenges to conserving native Fraxinus using biocontrol in the aftermath of the EAB invasion, and provide suggestions for program improvements as EAB spreads throughout North America. We conclude that more work is needed to: (1 evaluate the establishment and impact of biocontrol agents in different climate zones; (2 determine the combined effect of EAB biocontrol and host plant resistance or tolerance on the regeneration of North American ash species; and (3 expand foreign exploration for EAB natural enemies throughout Asia.

New management practice in the hotel business – The case of the hotel Excelsior

Directory of Open Access Journals (Sweden)

Ivona Vrdoljak

2004-01-01

Full Text Available The paper analyses the new management practice in the hotel industry. Over recent years, the environment for hotel management in Croatia has changed radically. Difficult business conditions require the transformation of management in the hotel industry. From the old-style business model, in which hotel managers were focused inwards on the hotel and its operation, a new paradigm encompassing a more externally oriented focus is now required. The current transformation of socially-owned hotels into capital-based and market-oriented business enterprises will accelerate the general process of privatisation and promote incentive management strategies. The article gives the research results of the new management practice in the case of the hotel "Excelsior" in Dubrovnik. It is one of the most successful hotels on the Croatian coast, which practises modern management. The research referred to management level, sex, age and educational structure of managers, their continuing education, knowledge, skills and characteristics of management, main functions of management, delegation of authorities and responsibilities, management system, decision-making, styles of leading and governing of managers by their time. The received results have been compared with the earlier management approach of the above-mentioned hotel. The objective of the paper is to point out the importance of the new management practice and its contribution to the successful hotel business.

PHYSIOLOGICAL AND FOLIAR INJURY RESPONSES OF PRUNUS SEROTINA, FRAXINUS AMERICANA, AND ACER RUBRUM SEEDLINGS TO VARYING SOIL MOISTURE AND OZONE. (R825244)

Science.gov (United States)

Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings wer...

Exploring public perceptions of solutions to tree diseases in the UK: Implications for policy-makers.

Science.gov (United States)

Jepson, Paul; Arakelyan, Irina

2017-10-01

Tree diseases are on the increase in many countries and the implications of their appearance can be political, as well as ecological and economic. Preventative policy approaches to tree diseases are difficult to formulate because dispersal pathways for pest and pathogens are numerous, poorly known and likely to be beyond human management control. Genomic techniques could offer the quickest and most predictable approach to developing a disease tolerant native ash. The population of European Ash ( Fraxinus Excelsi or) has suffered major losses in the last decade, due to the onset of Hymenoscyphus fraxineus (previously called Chalara Fraxinea ) commonly known in the UK as ash dieback. This study presents evidence on the public acceptability of tree-breed solutions to the spread of Chalara , with the main aim to provide science and policy with an up-stream 'steer' on the likely public acceptability of different tree breeding solutions. The findings showed that whilst there was a firm anti-GM and ' we shouldn't tamper with nature ' attitude among UK publics, there was an equally firm and perhaps slightly larger pragmatic attitude that GM (science and technology) should be used if there is a good reason to do so, for example if it can help protect trees from disease and help feed the world. The latter view was significantly stronger among younger age groups (Millennials), those living in urban areas and when the (GM)modified trees were destined for urban and plantation, rather than countryside settings. Overall, our findings suggest that the UK government could consider genomic solutions to tree breeding with more confidence in the future, as large and influential publics appear to be relaxed about the use of genomic techniques to increase tolerance of trees to disease.

Optimizing Use of Girdled Ash Trees for Management of Low-Density Emerald Ash Borer (Coleoptera: Buprestidae) Populations.

Science.gov (United States)

Siegert, Nathan W; McCullough, Deborah G; Poland, Therese M; Heyd, Robert L

2017-06-01

Effective survey methods to detect and monitor recently established, low-density infestations of emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), remain a high priority because they provide land managers and property owners with time to implement tactics to slow emerald ash borer population growth and the progression of ash mortality. We evaluated options for using girdled ash (Fraxinus spp.) trees for emerald ash borer detection and management in a low-density infestation in a forested area with abundant green ash (F. pennsylvanica). Across replicated 4-ha plots, we compared detection efficiency of 4 versus 16 evenly distributed girdled ash trees and between clusters of 3 versus 12 girdled trees. We also examined within-tree larval distribution in 208 girdled and nongirdled trees and assessed adult emerald ash borer emergence from detection trees felled 11 mo after girdling and left on site. Overall, current-year larvae were present in 85-97% of girdled trees and 57-72% of nongirdled trees, and larval density was 2-5 times greater on girdled than nongirdled trees. Low-density emerald ash borer infestations were readily detected with four girdled trees per 4-ha, and 3-tree clusters were as effective as 12-tree clusters. Larval densities were greatest 0.5 ± 0.4 m below the base of the canopy in girdled trees and 1.3 ± 0.7 m above the canopy base in nongirdled trees. Relatively few adult emerald ash borer emerged from trees felled 11 mo after girdling and left on site through the following summer, suggesting removal or destruction of girdled ash trees may be unnecessary. This could potentially reduce survey costs, particularly in forested areas with poor accessibility. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

Looking for age-related growth decline in natural forests: unexpected biomass patterns from tree rings and simulated mortality

Science.gov (United States)

Foster, Jane R.; D'Amato, Anthony W.; Bradford, John B.

2014-01-01

Forest biomass growth is almost universally assumed to peak early in stand development, near canopy closure, after which it will plateau or decline. The chronosequence and plot remeasurement approaches used to establish the decline pattern suffer from limitations and coarse temporal detail. We combined annual tree ring measurements and mortality models to address two questions: first, how do assumptions about tree growth and mortality influence reconstructions of biomass growth? Second, under what circumstances does biomass production follow the model that peaks early, then declines? We integrated three stochastic mortality models with a census tree-ring data set from eight temperate forest types to reconstruct stand-level biomass increments (in Minnesota, USA). We compared growth patterns among mortality models, forest types and stands. Timing of peak biomass growth varied significantly among mortality models, peaking 20–30 years earlier when mortality was random with respect to tree growth and size, than when mortality favored slow-growing individuals. Random or u-shaped mortality (highest in small or large trees) produced peak growth 25–30 % higher than the surviving tree sample alone. Growth trends for even-aged, monospecific Pinus banksiana or Acer saccharum forests were similar to the early peak and decline expectation. However, we observed continually increasing biomass growth in older, low-productivity forests of Quercus rubra, Fraxinus nigra, and Thuja occidentalis. Tree-ring reconstructions estimated annual changes in live biomass growth and identified more diverse development patterns than previous methods. These detailed, long-term patterns of biomass development are crucial for detecting recent growth responses to global change and modeling future forest dynamics.

CARACTERIZACIÓN BIOQUÍMICA PARCIAL DE PROTEÍNAS ALERGIÉNICAS DE FRAXINUS SINENSIS Y CECROPIA SP.

OpenAIRE

Rodríguez, Adriana; Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá; Leal, Francisco; Hospital Infantil Lorenzita Villegas de Santos, Bogotá

2013-01-01

The allergenic capabilities ofthe poli en of Fraxinus sinensis (Urapán) and Cecropia sp. (Y arumo) were determined in patients with respiratory allergies in the city ofBogotá. Of a total of207 patients wbo were subjected to therelevant allergy skin tests, 20 (9.66%) were positive for F. sinensis and 6 (2.9%) for the extract from Cecropia sp. The allergenicity was confirmed by the determination of specific Iinmunoglobulin E (lgE). Of the twenty patients positive for F. sinensis, only 6 ofthem ...

The hydraulic conductance of Fraxinus ornus leaves is constrained by soil water availability and coordinated with gas exchange rates.

Science.gov (United States)

Gortan, Emmanuelle; Nardini, Andrea; Gascó, Antonio; Salleo, Sebastiano

2009-04-01

Leaf hydraulic conductance (Kleaf) is known to be an important determinant of plant gas exchange and photosynthesis. Little is known about the long-term impact of different environmental factors on the hydraulic construction of leaves and its eventual consequences on leaf gas exchange. In this study, we investigate the impact of soil water availability on Kleaf of Fraxinus ornus L. as well as the influence of Kleaf on gas exchange rates and plant water status. With this aim, Kleaf, leaf conductance to water vapour (gL), leaf water potential (Psileaf) and leaf mass per area (LMA) were measured in F. ornus trees, growing in 21 different sites with contrasting water availability. Plants growing in arid sites had lower Kleaf, gL and Psileaf than those growing in sites with higher water availability. On the contrary, LMA was similar in the two groups. The Kleaf values recorded in sites with two different levels of soil water availability were constantly different from each other regardless of the amount of precipitation recorded over 20 days before measurements. Moreover, Kleaf was correlated with gL values. Our data suggest that down-regulation of Kleaf is a component of adaptation of plants to drought-prone habitats. Low Kleaf implies reduced gas exchange which may, in turn, influence the climatic conditions on a local/regional scale. It is concluded that leaf hydraulics and its changes in response to resource availability should receive greater attention in studies aimed at modelling biosphere-atmosphere interactions.

Hide and go seek with temperature signals of Northeastern US Tree Species

Science.gov (United States)

Alexander, M. R.; Pederson, N.; Bishop, D. A.; Pearl, J. K.; Anchukaitis, K. J.

2017-12-01

Improving reconstructions of past climate is vital in providing long-term context for regional climate change. There have been only two published reconstructions of past temperatures in the northeastern U.S. (NEUS) since the 1980s, one based on Picea rubens, and one out in 2017 based upon Chamaecyparis thyoides (Atlantic white cedar; AWC). Because increased species diversity generally improves dendrohydroclimatic reconstructions and both Picea rubens and AWC have limitations as paleoproxies due to land-use and air pollution, we conducted a series of tests to ask, "Does species diversity improve reconstructions of temperature history in the northeastern United States?" The first two tests were performed on AWC and then a network of AWC and Picea rubens. Subsequent tests added groups of species or genera from a network of 230 tree-ring chronologies beginning with those having the strongest relation between warming temperatures and increased growth. PC1 of the AWC test represented 40% of the variance and showed a significant positive relation with winter temperature (r = 0.38). As additional species were included, the "winter temperature PC" accounted for less of the overall variance, ranging from 26% of the variance in test 2 to 5% by test 5. AWC is swamped by the hydroclimatic signal that dominates our network. Populations of species such as Fagus grandifolia, Fraxinus nigra, Juniperus virginiana, Liriodendron tulipifera, Pinus rigida, and Pinus strobus from our network loaded strongest with AWC on the winter temperature PC. Including multiple species accounted for almost 20% more variance in the winter temperature record than AWC alone. Although drought is a dominating influence of tree growth in this region, our results suggest that winter temperatures are recorded within NEUS tree rings. Increasing the species diversity of tree proxies has the potential for improving reconstruction of paleotemperatures in regions lacking latitudinal or altitudinal tree lines

Can urban tree roots improve infiltration through compacted subsoils for stormwater management?

Science.gov (United States)

Bartens, Julia; Day, Susan D; Harris, J Roger; Dove, Joseph E; Wynn, Theresa M

2008-01-01

Global land use patterns and increasing pressures on water resources demand creative urban stormwater management. Strategies encouraging infiltration can enhance groundwater recharge and water quality. Urban subsoils are often relatively impermeable, and the construction of many stormwater detention best management practices (D-BMPs) exacerbates this condition. Root paths can act as conduits for water, but this function has not been demonstrated for stormwater BMPs where standing water and dense subsoils create a unique environment. We examined whether tree roots can penetrate compacted subsoils and increase infiltration rates in the context of a novel infiltration BMP (I-BMP). Black oak (Quercus velutina Lam.) and red maple (Acer rubrum L.) trees, and an unplanted control, were installed in cylindrical planting sleeves surrounded by clay loam soil at two compaction levels (bulk density = 1.3 or 1.6 g cm(-3)) in irrigated containers. Roots of both species penetrated the more compacted soil, increasing infiltration rates by an average of 153%. Similarly, green ash (Fraxinus pennsylvanica Marsh.) trees were grown in CUSoil (Amereq Corp., New York) separated from compacted clay loam subsoil (1.6 g cm(-3)) by a geotextile. A drain hole at mid depth in the CUSoil layer mimicked the overflow drain in a stormwater I-BMP thus allowing water to pool above the subsoil. Roots penetrated the geotextile and subsoil and increased average infiltration rate 27-fold compared to unplanted controls. Although high water tables may limit tree rooting depth, some species may be effective tools for increasing water infiltration and enhancing groundwater recharge in this and other I-BMPs (e.g., raingardens and bioswales).

Morphological and molecular characteristics of a new species of Pasteuria parasitic on Meloidogyne ardenensis.

Science.gov (United States)

Bishop, Alistair H; Gowen, Simon R; Pembroke, Barbara; Trotter, James R

2007-09-01

A species of the hyper-parasitic bacterium Pasteuria was isolated from the root-knot nematode Meloidogyne ardenensis infecting the roots of ash (Fraxinus excelsior). It is morphologically different from some other Pasteuria pathogens of nematodes in that the spores lack a basal ring on the ventral side of the spore and have a unique clumping nature. Transmission electron microscopy (TEM) showed that the clumps of spores are not random aggregates but result from the disintegration of the suicide cells of the thalli. Sporulation within each vegetative mycelium was shown to be asynchronous. In addition to the novel morphological features 16S rRNA sequence analysis showed this to be a new species of Pasteuria which we have called P. hartismeri. Spores of P. hartismeri attach to juveniles of root-knot nematodes infecting a wide range of plants such as mint (Meloidogyne hapla), rye grass (unidentified Meloidogyne sp.) and potato (Meloidogyne fallax).

Physiological and foliar injury responses of Prunus serotina, Fraxinus americana, and Acer rubrum seedlings to varying soil moisture and ozone

International Nuclear Information System (INIS)

Schaub, M.; Skelly, J.M.; Steiner, K.C.; Davis, D.D.; Pennypacker, S.P.; Zhang, J.; Ferdinand, J.A.; Savage, J.E.; Stevenson, R.E.

2003-01-01

High soil water availability favors ozone uptake, increases foliar injury, and exacerbates the negative ozone effect on gas exchange of seedlings of deciduous tree species. - Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings were exposed to three different ozone scenarios (ambient air: 100% O 3 ; non-filtered air: 98% ambient O 3 ; charcoal-filtered air: 50% ambient O 3 ) within each of two different water regimes (nine plots irrigated, nine plots non-irrigated) during three growing seasons. During the 1998 and 1999 growing season, leaf gas exchange, plant water relations, and foliar injury were measured. Climatic data, ambient- and chamber-ozone-concentrations were monitored. We found that seedlings grown under irrigated conditions had similar (in 1998) but significantly higher gas exchange rates (in 1999) than seedlings grown within non-irrigated plots among similar ozone exposures. Cherry and ash had similar ozone uptake but cherry developed more ozone-induced injury (<34% affected leaf area, LAA) than ash (<5% LAA), while maple rarely showed foliar injury, indicating the species differed in ozone sensitivity. Significantly more severe injury on seedlings grown under irrigated conditions than seedlings grown under non-irrigated conditions demonstrated that soil moisture altered seedling responses to ambient ozone exposures

Secoiridoids from the stem barks of Fraxinus rhynchophylla with pancreatic lipase inhibitory activity.

Science.gov (United States)

Ahn, Jong Hoon; Shin, Eunjin; Liu, Qing; Kim, Seon Beom; Choi, Kyeong-Mi; Yoo, Hwan-Soo; Hwang, Bang Yeon; Lee, Mi Kyeong

2013-01-01

Pancreatic lipase digests dietary fats by hydrolysis, which is a key enzyme for lipid absorption. Therefore, reduction of fat absorption by the inhibition of pancreatic lipase is suggested to be a therapeutic strategy for obesity. From the EtOAc-soluble fraction of the stem barks of Fraxinus rhynchophylla (Oleaceae), four secoiridoids such as ligstroside (1), oleuropein (2), 2"-hydroxyoleuropein (3) and hydroxyframoside B (4) were isolated. The inhibitory activity of these compounds on pancreatic lipase was assessed using porcine pancreatic lipase as an in vitro assay system. Compound 4 showed the strongest inhibition on pancreatic lipase, which followed by compounds 1-3. In addition, compound 4 exerted inhibitory effect on pancreatic lipase in a mixed mechanism of competitive and noncompetitive manner. Taken together, F. rhynchophylla and its constituents might be beneficial to obesity.

Effect of elevated atmospheric CO2 concentration on growth and leaf litter decomposition of Quercus acutissima and Fraxinus rhynchophylla

OpenAIRE

Cha, Sangsub; Chae, Hee-Myung; Lee, Sang-Hoon; Shim, Jae-Kuk

2017-01-01

The atmospheric carbon dioxide (CO2) level is expected to increase substantially, which may change the global climate and carbon dynamics in ecosystems. We examined the effects of an elevated atmospheric CO2 level on the growth of Quercus acutissima and Fraxinus rhynchophylla seedlings. We investigated changes in the chemical composition of leaf litter, as well as litter decomposition. Q. acutissima and F. rhynchophylla did not show differences in dry weight between ambient CO2 and enriched C...

Natural enemies implicated in the regulation of an invasive pest: a life table analysis of the population dynamics of the emerald ash Borer

Science.gov (United States)

The emerald ash borer (EAB), Agrilus planipennis Fairmaire, is a serious invasive forest pest that has killed tens of millions of ash (Fraxinus) trees in the United States and Canada. By caging EAB adults on trunks of healthy ash trees, we established three generations of experimental cohorts from ...

Bacteria associated with oak and ash on a TCE-contaminated site: characterization of isolates with potential to avoid evapotranspiration of TCE.

Science.gov (United States)

Weyens, Nele; Taghavi, Safiyh; Barac, Tanja; van der Lelie, Daniel; Boulet, Jana; Artois, Tom; Carleer, Robert; Vangronsveld, Jaco

2009-11-01

Along transects under a mixed woodland of English Oak (Quercus robur) and Common Ash (Fraxinus excelsior) growing on a trichloroethylene (TCE)-contaminated groundwater plume, sharp decreases in TCE concentrations were observed, while transects outside the planted area did not show this remarkable decrease. This suggested a possibly active role of the trees and their associated bacteria in the remediation process. Therefore, the cultivable bacterial communities associated with both tree species growing on this TCE-contaminated groundwater plume were investigated in order to assess the possibilities and practical aspects of using these common native tree species and their associated bacteria for phytoremediation. In this study, only the cultivable bacteria were characterized because the final aim was to isolate TCE-degrading, heavy metal resistant bacteria that might be used as traceable inocula to enhance bioremediation. Cultivable bacteria isolated from bulk soil, rhizosphere, root, stem, and leaf were genotypically characterized by amplified rDNA restriction analysis (ARDRA) of their 16S rRNA gene and identified by 16S rRNA gene sequencing. Bacteria that displayed distinct ARDRA patterns were screened for heavy metal resistance, as well as TCE tolerance and degradation, as preparation for possible future in situ inoculation experiments. Furthermore, in situ evapotranspiration measurements were performed to investigate if the degradation capacity of the associated bacteria is enough to prevent TCE evapotranspiration to the air. Between both tree species, the associated populations of cultivable bacteria clearly differed in composition. In English Oak, more species-specific, most likely obligate endophytes were found. The majority of the isolated bacteria showed increased tolerance to TCE, and TCE degradation capacity was observed in some of the strains. However, in situ evapotranspiration measurements revealed that a significant amount of TCE and its metabolites

Leaf gas exchange performance and the lethal water potential of five European species during drought.

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Li, Shan; Feifel, Marion; Karimi, Zohreh; Schuldt, Bernhard; Choat, Brendan; Jansen, Steven

2016-02-01

Establishing physiological thresholds to drought-induced mortality in a range of plant species is crucial in understanding how plants respond to severe drought. Here, five common European tree species were selected (Acer campestre L., Acer pseudoplatanus L., Carpinus betulus L., Corylus avellana L. and Fraxinus excelsior L.) to study their hydraulic thresholds to mortality. Photosynthetic parameters during desiccation and the recovery of leaf gas exchange after rewatering were measured. Stem vulnerability curves and leaf pressure-volume curves were investigated to understand the hydraulic coordination of stem and leaf tissue traits. Stem and root samples from well-watered and severely drought-stressed plants of two species were observed using transmission electron microscopy to visualize mortality of cambial cells. The lethal water potential (ψlethal) correlated with stem P99 (i.e., the xylem water potential at 99% loss of hydraulic conductivity, PLC). However, several plants that were stressed beyond the water potential at 100% PLC showed complete recovery during the next spring, which suggests that the ψlethal values were underestimated. Moreover, we observed a 1 : 1 relationship between the xylem water potential at the onset of embolism and stomatal closure, confirming hydraulic coordination between leaf and stem tissues. Finally, ultrastructural changes in the cytoplasm of cambium tissue and mortality of cambial cells are proposed to provide an alternative approach to investigate the point of no return associated with plant death. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Phytochemical characterization of the threatened specie Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi

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Mabelkis Terry Rosabal

2016-04-01

Full Text Available Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi is commonly known as buffalo, represents an endemic subspecies and categorized as critical danger of extinction in Cuba. This work aimed to characterize the phytochemical composition of plants of F. caroliniana in two localities of the Matanzas province. The presence of secondary metabolites in leaf extracts was qualitatively analyzed and reductive and total sugars were quantified. The results indicated the presence of flavonoids, terpenes, steroids, saponins, tannins and anthraquinones in leaves that could be considered for further systematic studies and application in agriculture. The plants from the Ciénaga de Zapata showed contents of reducing sugars and totals higher than those obtained in the plants of Martí. These results provide information for the identification of characters of possible taxonomic and conservation value in this species.   Keywords: anthraquinons, extracts, swamp ash, steroids, tannins, terpens

Indirect effects of emerald ash borer-induced ash mortality and canopy gap formation on epigaeic beetles.

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Gandhi, Kamal J K; Smith, Annemarie; Hartzler, Diane M; Herms, Daniel A

2014-06-01

Exotic herbivorous insects have drastically and irreversibly altered forest structure and composition of North American forests. For example, emerald ash borer (Agrilus planipennis Fairmaire) from Asia has caused wide-scale mortality of ash trees (Fraxinus spp.) in eastern United States and Canada. We studied the effects of forest changes resulting from emerald ash borer invasion on epigaeic or ground beetles (Coleoptera: Carabidae) along a gradient of ash dieback and gap sizes in southeastern Michigan. Ground beetles were sampled in hydric, mesic, and xeric habitats in which black (Fraxinus nigra Marshall), green (Fraxinus pennsylvanica Marshall), and white (Fraxinus americana L.) ash were the most common species, respectively. During 2006-2007, we trapped 2,545 adult ground beetles comprising 52 species. There was a negative correlation between percent ash tree mortality in 2006 and catches of all beetles. Catches of Agonum melanarium Dejean (in 2006) and Pterostichus mutus (Say) (in 2006-2007) were negatively correlated with tree mortality and gap size, respectively. However, catches of Pterostichus corvinus Dejean were positively correlated with gap size in 2006. As ash mortality and average gap size increased from 2006 to 2007, catches of all beetles as well as P. mutus and Pterostichus stygicus (Say) increased (1.3-3.9 times), while species diversity decreased, especially in mesic and xeric stands. Cluster analysis revealed that beetle assemblages in hydric and mesic stand diverged (25 and 40%, respectively) in their composition from 2006 to 2007, and that hydric stands had the most unique beetle assemblages. Overall, epigaeic beetle assemblages were altered in ash stands impacted by emerald ash borer; however, these impacts may dissipate as canopy gaps close.

Establishment Success of Coexisting Native and Exotic Trees Under an Experimental Gradient of Irradiance and Soil Moisture

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González-Muñoz, Noelia; Castro-Díez, Pilar; Fierro-Brunnenmeister, Natalia

2011-10-01

The exotic trees Ailanthus altissima, Robinia pseudoacacia, Acer negundo and Elaeagnus angustifolia coexist with the native trees Fraxinus angustifolia and Ulmus minor in river banks of central Spain. Similarly, the exotic trees Acacia dealbata and Eucalyptus globulus co-occur with the natives Quercus pyrenaica and Pinus pinaster in Northwest Spain. We aimed to identify the environmental conditions that favour or hamper the establishment success of these species. In spring 2008, seeds of the studied species were sown under an experimental gradient of light (100, 65, 35, 7% of full sunlight) combined with three levels of soil moisture (mean soil water potential = -0.97, -1.52 and -1.77 MPa.). During the first growing season we monitored seed emergence and seedling survival. We found that the effect of light on the establishment success was stronger than the effect of soil moisture. Both exotic and native species of central Spain showed a good performance under high light, A. negundo being the most shade tolerant . Water shortage diminished E. angustifolia and A. altissima success. Among NW Spain species, A. dealbata and P. pinaster were found to be potential competitors for colonizing high-irradiance scenarios, while Q. pyrenaica and E. globulus were more successful under moderate shade. High soil moisture favoured E. globulus but not A. dealbata establishment. These results contribute to understand some of the factors controlling for spatial segregation between coexisting native and exotic tree species, and can help to take decisions orientated to the control and management of these exotic species.

SLAM: A multi-agency pilot project to SL.ow A.sh M.ortality caused by emerald ash borer in outlier sites

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Therese M. Poland; Deborah G. McCullough

2010-01-01

Since its discovery in southeast Michigan in 2002, the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), has continued to spread and kill ash (Fraxinus) trees at an alarming rate. As of February 2010, EAB has killed tens of millions of ash trees in Michigan, at least 12 additional U.S. states, and the...

[Spatial variation in diurnal courses of stem temperature of Betula platyphylla and Fraxinus mandshurica and its influencing factors].

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Li, Yu Ran; Wang, Xing Chang; Wang, Chuan Kuan; Liu, Fan; Zhang, Quan Zhi

2017-10-01

Plant temperature is an important parameter for estimating energy balance and vegetation respiration of forest ecosystem. To examine spatial variation in diurnal courses of stem temperatures (T s ) and its influencing factors, we measured the T s with copper constantan thermocouples at different depths, heights and azimuths within the stems of two broadleaved tree species with contrasting bark and wood properties, Betula platyphylla and Fraxinus mandshurica. The results showed that the monthly mean diurnal courses of the T s largely followed that of air temperature with a 'sinusoi dal' pattern, but the T s lagged behind the air temperature by 0 h at the stem surface to 4 h at 6 cm depth. The daily maximal values and ranges of the diurnal course of T s decreased gradually with increasing measuring depth across the stem and decreasing measuring height along the stem. The circumferential variation in T s was marginal, with slightly higher daily maximal values in the south and west directions during the daytime of the dormant season. Differences in thermal properties (i.e. , specific heat capacity and thermal conductivity) of both bark and wood tissue between the two species contributed to the inter specific variations in the radial variation in T s through influencing the heat exchange between the stem surface and ambient air as well as heat diffusion within the stem. The higher reflectance of the bark of B. platyphylla decreased the influence of solar radiation on T s . The stepwise regression showed that the diurnal courses of T s could be well predicted by the environmental factors (R 2 > 0.85) with an order of influence ranking as air temperature > water vapor pressure > net radiation > wind speed. It is necessary to take the radial, vertical and inter specific varia-tions in T s into account when estimating biomass heat storage and stem CO2 efflux.

Natural infections of Beauveria bassiana in Agrilus planipennis populations in Michigan

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Louela A. Castrillo; Leah S. Bauer; Houping Liu; Michael H. Griggs; John D. Vandenberg

2009-01-01

The emerald ash borer (EAB), Agrilus planipennis (Coleoptera, Buprestidae), is an invasive pest from Asia posing a serious threat to ash trees (Fraxinus spp.) in North America. Beetles have a 1- or 2...

Quantifying coastal erosion rates using anatomical change in exposed tree roots at Porquerolles Island (Var, France).

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Morel, Pauline; Corona, Christophe; Lopez-Saez, Jérôme; Rovéra, Georges; Dewez, Thomas; Stoffel, Markus; Berger, Frédéric

2017-04-01

tree roots: Two examples from central Spain. Catena 64 : 81-102. Fantucci R. 2007. Dendrogeomorphological analysis of shore erosion along Bolsena lake (central Italy). Dendrochronologia 24 : 130-140. Giuliano J. Érosion des falaises de la région Provence-Alpes-Côte d'Azur : évolution et origine de la morphologie côtière en Méditerranée : télédétection, géochronologie, géomorphologie. Sciences de la Terre. Université Nice Sophia Antipolis, 2015. Français. . Hitz O, Gärtner H, Heinrich I, Monbaron M, 2008a. Application of ash (Fraxinus excelsior l.) roots to determine erosion rates in mountain torrents. Catena 72 : 248-258. Lopez Saez J, Corona C, Stoffel M, Rovéra G, Astrade L, Berger F. 2011. Mapping of erosion rates in marly badlands based on a coupling of anatomical changes in exposed roots with slope maps derived from LiDAR data. Earth Surface Processes and Landforms 36 : 1162-1171. Lucía, A., Laronne, J. B., & Martín-Duque, J. F. (2011). Geodynamic processes on sandy slope gullies in central Spain field observations, methods and measurements in a singular system. Geodinámica acta, 24(2), 61-79. Malik I. 2008. Dating of small gully formation and establishing erosion rates in old gullies under forest by means of anatomical changes in exposed tree roots (Southern Poland). Geomorphology 93 : 421-436.
 Malik I. 2006. Gully erosion dating by means of anatomical changes in exposed roots (Proboszczowicka plateau, Southern Poland). Geochronometria 25 : 57-66. Stoffel M, Casteller A, Luckman B H, Villalba R, 2012. Spatiotemporal analysis of channel wall erosion in ephemeral torrents using tree roots - An example from the Patagonian Andes. Geology40 : 247-250. Vandekerckhove L. 2001. Short-term bank gully retreat rates in Mediterranean environments. Catena 44 : 133-161.

Monitoring the establishment and flight phenology of parasitoids of emerald ash borer (Coleoptera: Buprestidae) in Michigan by using sentinel eggs and larvae

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Kristopher J. Abell; Leah S. Bauer; Deborah L. Miller; Jian J. Duan; Roy G. Van Driesche

2016-01-01

The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an important invasive pest of ash (Fraxinus) trees in North America. Two larval parasitoid species, Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) and Spathius agrili Yang (Hymenoptera:...

Evaluation of Agrilus planipennis (Coleoptera: Buprestidae) control provided by emamectin benzoate and two neonicotinoid insecticides, one and two seasons after treatment.

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McCullough, Deborah G; Poland, Therese M; Anulewicz, Andrea C; Lewis, Phillip; Cappaert, David

2011-10-01

Effective methods are needed to protect ash trees (Fraxinus spp.) from emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), an invasive buprestid that has killed millions of North American ash (Fraxinus spp.) trees. We randomly assigned 175 ash trees (11.5-48.1 cm in diameter) in 25 blocks located in three study sites in Michigan to one of seven insecticide treatments in May 2007. Treatments included 1) trunk-injected emamectin benzoate; 2) trunk-injected imidacloprid; 3) basal trunk spray of dinotefuran with or 4) without Pentra-Bark, an agricultural surfactant; 5) basal trunk spray of imidacloprid with or 6) without Pentra-Bark; or (7) control. Foliar insecticide residues (enzyme-linked immunosorbent assay) and toxicity of leaves to adult A. planipennis (4-d bioassays) were quantified at 3-4-wk intervals posttreatment. Seven blocks of trees were felled and sampled in fall 2007 to quantify A. planipennis larval density. Half of the remaining blocks were retreated in spring 2008. Bioassays and residue analyses were repeated in summer 2008, and then all trees were sampled to assess larval density in winter. Foliage from emamectin benzoate-treated trees was highly toxic to adult A. planipennis, and larval density was emamectin benzoate for > or = 2 yr may reduce costs or logistical issues associated with treatment.

Radiocarbon Records of Fossil Fuel Emissions From Urban Trees in the Greater Salt Lake Valley From Mid-Century to Present.

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Chritz, K.; Buchert, M.; Walker, J. C.; Mendoza, D.; Pataki, D. E.; Xu, X.; Lin, J. C.

2017-12-01

Generating long term records of fossil fuel emissions of urban environments is complicated by the fact that direct observations of emissions and urban atmospheric CO2 concentrations were only collected in the recent past. Radiocarbon (14C) in tree rings from urban trees can provide archives of fossil fuel emissions that may track population growth over time, as higher population density is typically correlated with increased vehicular traffic and associated CO2 emissions, which are radiocarbon dead. We present radiocarbon measurements (n=125) from five roadside green ash trees (Fraxinus pennsylvanica) located in three cities of northern Utah - Salt Lake City (urban, 2016 population: 193,744), Logan City (agricultural, 2016 population: 49,110) and Heber (rural, 2016 population: 14,969). Urban trees were cored in four cardinal directions and ring widths were measured and counted to establish a chronology. One ring from every third year in a single core from each tree was removed and holocellulose was extracted from bulk wood of individual rings for 14C analysis. Fraction CO2 from fossil fuel burning (CO2-ff) was calculated using a simple mass-balance calculation from measured 14C values and remote background atmospheric 14CO2 values for NH Zone 2. The data from all three cities indicate a general trend of increasing CO2-ff uptake by the trees from 1980s to present, as expected with increased population growth and vehicular traffic. However, records in all three cities show unique elevated CO2-ff prior to the 1980s, assuming similar climate patterns through time, diverging from historic population size. We employed atmospheric simulations from the STILT (Stochastic Time-Inverted Lagrangian Transport) models for each of these trees to create footprints to determine source areas for CO2. These footprints reveal that atmospheric sampling areas can be large for certain trees, and other sources of 14C dead carbon, such as coal and natural gas from industrial emissions

Branch Wood Decomposition of Tree Species in a Deciduous Temperate Forest in Korea

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Sangsub Cha

2017-05-01

Full Text Available Woody debris, which is supplied by branch litter, is an important component of forest ecosystems as it contains large quantities of organic matter and nutrients. We evaluated changes in branch wood dry weight and nutrient content of six common species (Fraxinus rhynchophylla, Pinus densiflora, Prunus sargentii, Quercus mongolica, Acer pseudosieboldianum, and Symplocos chinensis for. pilosa in a deciduous temperate forest in Korea for 40 months. Branch wood disk samples 1.4–1.6 cm thick were cut, and mass loss was measured over time using the litterbag method. No significant differences in mass loss were recorded among the six tree species. Further, mass loss was negatively correlated with initial lignin concentration and positively correlated with both initial cellulose concentration and wood density for each species. Species with high wood cellulose content had high wood density while the lignin content in wood was relatively low. Accordingly, cellulose contributed to wood density, creating a relatively lower lignin content, and the decreased lignin concentration increased the wood decomposition rate.

Effects of Bacillus thuringiensis SDS-502 on adult emerald ash borer

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Leah S. Bauer; Diana K. Londo& #241; o

2011-01-01

Emerald ash borer (EAB), Agrilus planipennis, an intermittent pest of ash (Fraxinus) trees in northeastern Asia, was discovered in Michigan and Ontario in 2002. In North America, infestations of EAB are now known in 13 states and 2 provinces.

Ecological pattern of lichen species abundance in mixed forests of Eastern Romania

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Ioana Vicol

2016-12-01

Full Text Available The importance of this study consists in the knowledge of the ecological attributes characteristic to mixed forestry habitats and how they affect the structure of the lichen species abundances. The field activities were performed within five forest habitat types from Moldavia Province, characterised mainly by oak mixed forests, riparian mixed forests and mixed beech forests. The habitat variables, tree variables and the lichen species abundances were analysed to get informations on the structural disimilarities, on the one hand, and relationships on the other hand. Within this study no significant disimilarities were found out from abundance lichen species point of view. The lichen species abundances are a result of interactions between components of their microhabitat and macrohabitat. The correlation analysis pointed out the preferences of lichen species to their host trees, especially Quercus and Fraxinus, altitude and tree level variables as are aspect and mosses coverage. The regression analysis has highlighted that the changes in lichen species abundances are caused by macrohabitat level predictors such as host trees represented by Fraxinus. This study demonstrates that, structure of lichen species is influenced by attributes of mixed forest habitats; therefore maintaining the diversity of tree species and ensuring the continuous occurrence of forestry land is necessary for lichen and their habitat conservation.

Comparing the Sexual Reproductive Success of Two Exotic Trees Invading Spanish Riparian Forests vs. a Native Reference.

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Cabra-Rivas, Isabel; Castro-Díez, Pilar

2016-01-01

A widely accepted hypothesis in invasion ecology is that invasive species have higher survival through the early stages of establishment than do non-invasive species. In this study we explore the hypothesis that the sexual reproductive success of the invasive trees Ailanthus altissima (Mill.) Swingle and Robinia pseudoacacia L. is higher than that of the native Fraxinus angustifolia Vahl., all three species coexisting within the riparian forests of Central Spain. We compared different stages of the early life cycle, namely seed rain, seed infestation by insects, seed removal by local fauna, seed germination under optimal conditions and seedling abundance between the two invasive trees and the native, in order to assess their sexual reproductive success. The exotic species did not differ from the native reference (all three species displaying high seed rain and undergoing seed losses up to 50% due to seed removal by the local fauna). Even if the exotic R. pseudoacacia showed a high percentage of empty and insect-parasited seeds along with a low seedling emergence and the exotic A. altissima was the species with more viable seeds and of higher germinability, no differences were found regarding these variables when comparing them with the native F. angustifolia. Unsuitable conditions might have hampered either seedling emergence and survival, as seedling abundance in the field was lower than expected in all species -especially in R. pseudoacacia-. Our results rather suggest that the sexual reproductive success was not higher in the exotic trees than in the native reference, but studies focusing on long-term recruitment would help to shed light on this issue.

Ground cover and tree growth on calcareous minesoils: Greater influence of soil surface than nitrogen rate or seed mix

International Nuclear Information System (INIS)

Kost, D.A.; Vimmerstedt, J.P.

1994-01-01

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 m 2 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)

Tree bark suber-included particles: A long-term accumulation site for elements of atmospheric origin

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Catinon, Mickaël; Ayrault, Sophie; Spadini, Lorenzo; Boudouma, Omar; Asta, Juliette; Tissut, Michel; Ravanel, Patrick

2011-02-01

The deposition of atmospheric elements on and into the bark of 4-year-old Fraxinus excelsior L. was studied. The elemental composition of the suber tissue was established through ICP-MS analysis and the presence of solid mineral particles included in this suber was established and described through SEM-EDX. Fractionation of the suber elements mixture was obtained after ashing at 550 °C through successive water (C fraction) and HNO 3 2 M (D fraction) extraction, leading to an insoluble residue mainly composed of the solid mineral particles (E fraction). The triplicated % weight of C, D and E were respectively 34.4 ± 2.7, 64.8 ± 2.7 and 0.8 ± 0.1% of the suber ashes weight. The main component of C was K, of D was Ca. Noticeable amounts of Mg were also observed in D. The E fraction, composed of insoluble particles, was mostly constituted of geogenic products, with elements such as Si, Al, K, Mg, representing primary minerals. E also contained Ca 3(PO 4) 2 and concentrated the main part of Pb and Fe. Moreover, The SEM-EDX analysis evidenced that this fraction also concentrated several types of fly ashes of industrial origin. The study of the distribution between C, D and E was analysed through ICP-MS with respect to their origin. The origin of the elements found in such bark was either geogenic (clay, micas, quartz…), anthropogenic or biogenic (for instance large amounts of solid Ca organic salts having a storage role). As opposed to the E fraction, the C fraction, mainly composed of highly soluble K+ is characteristic of a biological pool of plant origin. In fraction D, the very high amount of Ca++ corresponds to two different origins: biological or acid soluble minerals such as calcite. Furthermore, the D fraction contains the most part of pollutants of anthropic origin such as Zn, Cu, Ni, Co, Cd. As a whole, the fractionation procedure of the suber samples allows to separate elements as a function of their origin but also gives valuable information on

Schizophyllum commune: The main cause of dying trees of the Banja Luka arbored walks and parks

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Matavulj Milan N.

2013-01-01

Full Text Available In the frame of investigation of the main cause of dying trees of the main arbored walks (Mladena Stojanovića Aley and Park, the investigation of the presence and diversity of macrofungi in Banja Luka City were undertaken in the period 2006-2011. Relatively poor generic diversity of lignicolous (pathogenic or potentially pathogenic and saprotrophic macrofungi with only 16 species representing this group (13 basidiomycets: Schizophyllum commune, Fomes fomentarius, Stereum hirsutum, Coriolus versicolor, Flammulina velutipes, Pseudotrametes gibbosa, Ganoderma applanatum, G. lucidum, G. adspersum, Polyporus squamosus, Meripilus giganteus, Laetiporus sulphureus, Auricu­laria auricula-judae, and 3 ascomycets: Nectria cinnabarina, Xylaria hypoxylon, X. poly­morpha were recorded. Such a poor qualitative composition of this very important fungal group could be explained by the reduction in the number of plant species in arbored walks and alleys, as well as the reduction in the number of fungi resistant to heavy air pollution caused by nearby (1-5m fuel combustion in engines. Although only preliminary, our results pointed to the necessity of conservation and protection of the most beautiful features of Banja Luka and its alleys and arbored walks, by undertaking the measures of curing damaged trees and treating them with fungicides in order to wipe out the epiphytia caused in more than 95% of cases (dated May 2011 by Split-gill (Schizophyllum commune, present on dead wood but also on damaged trees of Aesculus hyppocastaneum (127 trees, Tilia cordata (124 trees, Tilia platyphyllos (36 trees, Tilia argentea (40 trees, Acer negundo (20 trees, Platanus acerifolia (2 trees, Robinia pseudoacacia (3 trees, Fraxinus ornus (1 tree, Betula pendula (1 tree, Catalpa sp. (2 trees, etc. Altogether, during the last decade, around 200 trees collapsed or were sanitary cut in Banja Luka arbored walk from the Malta site to the Green bridge, a total length around 5 km. The

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

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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.

Complex Ornament Machining Process on a CNC Router

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Camelia COŞEREANU

2014-03-01

Full Text Available The paper investigates the CNC routering possibilities for three species of wood, namely ash (Fraxinus Excelsior, lime wood (Tilia cordata and fir wood (Abies Alba, in order to obtain right surfaces of Art Nouveau sculptured ornaments. Given the complexity of the CNC tool path for getting wavy shapes of Art Nouveau decorations, the choice of processing parameters for each processed species of wood requires a laborious research work to correlate these parameters. Two Art Nouveau ornaments are proposed for the investigation. They are CNC routered using two types of cutting tools. The processed parameters namely the spindle speed, feed speed and depth of cut were the three variables of the machining process for the three species of wood, which were combined so, to provide good surface finish as a quality attribute. There were totally forty six variants of combining the processing parameter which were applied for CNC routering the samples made of the three species of wood. At the end, an optimum combination of the processed parameters is recommended for each species of wood.

Energetic evaluation of indigenous tree and shrub species in Basilicata, Southern Italy

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Todaro L

2007-01-01

Full Text Available An evaluation of energetic characteristics such as high calorific value (on ash-free dry weight basis, ash, carbon, nitrogen, and moisture content of 12 indigenous tree and shrub species of Southern Italy (Basilicata Region was carried out. The studied species are the most abundant in this area: Quercus cerris L., Quercus pubescens Willd., Fraxinus ornus L., Populus canescens (Aiton Smith, Salix alba L., Alnus cordata L., Robinia pseudoacacia L., Olea europaea L., Spartium junceum L., Rubus hirtus W., Onopordum illirium L., Arundo donax L. For Q. cerris, Q. pubescens and O. europaea L., the energetic characteristics were measured by separating the wood components from the leaves. Q. cerris leaves contained the greatest high calorific value. F. ornus leaves had a greater ash content than the other samples while the lowest values were measured for S. junceum, Q. pubescens and R. pseudoacacia. The highest content of Carbon was in O. europaea leaves. A. donax and O. illirium had the lower level of high calorific value and Carbon than all the other species. The highest Nitrogen content was measured in Q. cerris leaves and the lowest one in F. ornus wood components.

Biology and life history of Atanycolus cappaerti (Hymenoptera: Braconidae), a north american larval parasitoid attacking the invasive Emerald Ash Borer (Coleoptera: Buprestidae)

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Atanycolus cappaerti Marsh and Strazanac is a native North American parasitoid that has been found to parasitize the emerald ash borer, Agrilus planipennis Fairmaire, a serious invasive pests of North American ash trees (Fraxinus spp.). To facilitate the development of potential augmentative biocon...

Population biology of emerald ash borer and its natural enemies in China

Science.gov (United States)

Houping Liu; Leah S. Bauer; Tonghai Zhao; Ruitong Gao

2008-01-01

Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), also known as emerald ash borer (EAB), was first discovered in Michigan and Ontario, Canada, in 2002 following investigations of declining and dying ash trees (Fraxinus spp.). Agrilus planipennis has also spread to Ohio, Indiana, Maryland, Virginia,...

Seasonal embolism and xylem vulnerability in deciduous and evergreen Mediterranean trees influenced by proximity to a carbon dioxide spring

Energy Technology Data Exchange (ETDEWEB)

Tognetti, R.; Raschi, A. [Consiglio Nazionale della Ricerche, Firenze (Italy); Longobucco, A. [Centro Studi per l`Informatica applicata all`Agricoltura, Firenze (Italy)

1999-04-01

The effect of proximity to natural CO{sub 2} springs on seasonal patterns of xylem embolism in various species of Quercus (oak), Fraxinus, Populus (poplar) and Arbutus was studied. Xylem embolism was evaluated in both artificially dehydrated branches and in hydrated apical branches collected at monthly intervals over a 20-month period. Species-dependent differences in xylem hydraulic properties in response to elevated CO{sub 2} were noted. Populus tremula was the most embolized, an Arbutus unedo was the least embolized among the species examined. The actual differences in xylem vulnerability between trees growing near the CO{sub 2} spring and those growing in control area were small, however, these differences combined with the interaction of seasonal stress events, may be of great importance in determining future community composition in Mediterranean forest ecosystems. Causes and ecological significance of such differences are discussed vis-a-vis elevated carbon dioxide concentration and other environmental factors. 48 refs., 2 tabs., 3 figs.

Evaluation of recovery and monitoring methods for parasitoids released against Emerald Ash Borer

Science.gov (United States)

The emerald ash borer (Agrilus planipennis Fairmaire, EAB) is an invasive insect pest, and the target of an extensive biological control campaign designed to mitigate EAB driven ash tree (Fraxinus spp.) mortality. Since 2007, environmental releases of three species of hymenopteran parasitoids of EA...

Monitoring the establishment and flight phenology of egg and larval parasitoids of emerald ash borer (Coleoptera: Buprestidae) in Michigan, USA using sentinel eggs and larvae

Science.gov (United States)

Emerald ash borer (EAB), Agrilus planipennis Fairmaire, is an important invasive pest of ash (Fraxinus) trees in North America. Two larval parasitoids, Tetrastichus planipennisi Yang and Spathius agrili Yang, and one egg parasitoid, Oobius agrili Zhang and Huang, were introduced into the United Sta...

Dispersal of the emerald ash borer, Agrilus planipennis, in newly-colonized sites

Science.gov (United States)

Rodrigo J. Mercader; Andrew M. Siegert; Andrew M. Liebhold; Deborah G. McCullough

2009-01-01

Emerald ash borer Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive forest insect pest threatening more than 8 billion ash (Fraxinus spp.) trees in North America. Development of effective survey methods and strategies to slow the spread of A. planipennis requires an understanding of dispersal...

Temporal dynamics of woodpecker predation on the invasive emerald ash borer (Agrilus planipennis) in North America

Science.gov (United States)

Woodpeckers (Picidae) are among the most prevalent natural enemies attacking the invasive emerald ash borer (EAB), Agrilus planipennis Fairmaire, in North America, but there can be considerable variation in the levels of EAB predation on ash trees (Oleaceae: Fraxinus) within and between sites as wel...

Long-term monitoring of the introduced emerald ash borer (Coleoptera: Buprestidae) egg parasitoid, oobius agrili (Hymenoptera: Encyridae), in Michigan, USA and evaluation of a newly developed monitoring technique

Science.gov (United States)

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of ash trees (Fraxinus spp.) in North America. The egg parasitoid Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) was introduced as a biological control agent of this pest in Michiga...

Susceptibility of two hymenopteran parasitoids of Agrilus planipennis (Coleoptera: Buprestidae) to the entomopathogenic fungus Beauveria bassiana (Ascomycota: Hypocreales)

Science.gov (United States)

Emerald ash borer (EAB), Agrilus planipennis Fairmaire, native to Asia, is killing ash trees (Fraxinus spp.) in eastern North America. Integrated pest management using biological control is the only viable long-term approach for controlling the spread of EAB outside of host resistance. Three hymen...

Citizen science identifies the effects of nitrogen deposition, climate and tree species on epiphytic lichens across the UK.

Science.gov (United States)

Welden, N A; Wolseley, P A; Ashmore, M R

2018-01-01

A national citizen survey quantified the abundance of epiphytic lichens that are known to be either sensitive or tolerant to nitrogen (N) deposition. Records were collected across the UK from over 10,000 individual trees of 22 deciduous species. Mean abundance of tolerant and sensitive lichens was related to mean N deposition rates and climatic variables at a 5 km scale, and the response of lichens was compared on the three most common trees (Quercus, Fraxinus and Acer) and by assigning all 22 tree species to three bark pH groups. The abundance of N-sensitive lichens on trunks decreased with increasing total N deposition, while that of N-tolerant lichens increased. The abundance of N-sensitive lichens on trunks was reduced close to a busy road, while the abundance of N-tolerant lichens increased. The abundance of N-tolerant lichen species on trunks was lower on Quercus and other low bark pH species, but the abundance of N-sensitive lichens was similar on different tree species. Lichen abundance relationships with total N deposition did not differ between tree species or bark pH groups. The response of N-sensitive lichens to reduced nitrogen was greater than to oxidised N, and the response of N-tolerant lichens was greater to oxidised N than to reduced N. There were differences in the response of N-sensitive and N-tolerant lichens to rainfall, humidity and temperature. Relationships with N deposition and climatic variables were similar for lichen presence on twigs as for lichen abundance on trunks, but N-sensitive lichens increased, rather than decreased, on twigs of Quercus/low bark pH species. The results demonstrate the unique power of citizen science to detect and quantify the air pollution impacts over a wide geographical range, and specifically to contribute to understanding of lichen responses to different chemical forms of N deposition, local pollution sources and bark chemistry. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparing the Sexual Reproductive Success of Two Exotic Trees Invading Spanish Riparian Forests vs. a Native Reference.

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Isabel Cabra-Rivas

Full Text Available A widely accepted hypothesis in invasion ecology is that invasive species have higher survival through the early stages of establishment than do non-invasive species. In this study we explore the hypothesis that the sexual reproductive success of the invasive trees Ailanthus altissima (Mill. Swingle and Robinia pseudoacacia L. is higher than that of the native Fraxinus angustifolia Vahl., all three species coexisting within the riparian forests of Central Spain. We compared different stages of the early life cycle, namely seed rain, seed infestation by insects, seed removal by local fauna, seed germination under optimal conditions and seedling abundance between the two invasive trees and the native, in order to assess their sexual reproductive success. The exotic species did not differ from the native reference (all three species displaying high seed rain and undergoing seed losses up to 50% due to seed removal by the local fauna. Even if the exotic R. pseudoacacia showed a high percentage of empty and insect-parasited seeds along with a low seedling emergence and the exotic A. altissima was the species with more viable seeds and of higher germinability, no differences were found regarding these variables when comparing them with the native F. angustifolia. Unsuitable conditions might have hampered either seedling emergence and survival, as seedling abundance in the field was lower than expected in all species -especially in R. pseudoacacia-. Our results rather suggest that the sexual reproductive success was not higher in the exotic trees than in the native reference, but studies focusing on long-term recruitment would help to shed light on this issue.

The emerald ash borer: a new exotic pest in North America

Science.gov (United States)

Robert A. Haack; Eduard Jendak; Liu Houping; Keneth R. Marchant; Toby R. Petrice; Therese M. Poland; Hui Ye

2002-01-01

Yet another new exotic forest pest has been discovered in North America, and this time the infestation is centered in Michigan and Ontario. In May and June 2002, adults of an unidentified buprestid beetle were collected from ash (Fraxinus) trees in the Detroit area of southeastern Michigan.

Flight potential of the emerald ash borer

Science.gov (United States)

Leah S. Bauer; Deborah L. Miller; Robin A.J. Taylor; Robert A. Haack

2004-01-01

The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive pest of ash trees (Fraxinus spp.) in North America. Native to several Asian countries, EAB was discovered in six southeastern Michigan counties and southwestern Ontario in 2002. EAB presumably emerged from infested solid wood...

Developing rearing methods for Tetrastichus planipennisi (Hymenoptera: Eulophidae), a larval endoparasitoid of the emerald ash borer (Coleoptera: Buprestidae)

Science.gov (United States)

Jian J. Duan; Mike Ulyshen; Leah Bauer; Ivich. Fraser

2011-01-01

Tetrastichus planipennisi Yong, a gregarious koinobiont endoparasitoid, is one of three hymenopteran parasitoids being released in the U.S. for biological control of the emerald ash borer (Agrilus planipennis Fairmair, EAB), an invasive beetle from Asia causing mortality of the ash trees (Fraxinus spp.) in North...

Emerald Ash Borer Microbial Control with the Entomopathogen Beauveria bassiana GHA formulated as Botanigard®

Science.gov (United States)

Houping Lui; Leah S. Bauer

2008-01-01

The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), a sporadic wood-boring pest native to northeastern Asia, was found attacking ash trees (Fraxinus spp.) in southeastern Michigan in 2002. Despite regulatory efforts to quarantine and eradicate EAB, this invasive beetle has continued to spread...

Environmental Assessment for BRAC Facilities and Remote Field Training Site, Wright-Patterson Air Force Base

Science.gov (United States)

2008-03-01

survey (BHE, 2001). Radio tracking of these two bats confirmed the presence of a maternity colony in a dead slippery elm (Ulmus rubra) in a woodlot...The most common trees observed were black walnut (Juglans nigra), elm (Ulmus spp.), eastern cottonwood, willow, ash (Fraxinus americana), sycamore

Environmental Impact Study of the Northern Section of the Upper Mississippi River. Pool 5.

Science.gov (United States)

1973-11-01

commercially valuable tree species: silver maple (Acer saccharinum), American elm (Ulmus americana), slippery elm (Ulmus rubrea), green ash (Fraxinus...this division is generally birch, elm , and cotton wood, all the cliffs being bordered by cedars. The navigation, as far as the Iowa River is good, but

Lichen communities as bioindicators of the Aburra Valley air quality

International Nuclear Information System (INIS)

Jaramillo C, Margarita M; Botero B, Liliana R

2010-01-01

Lichens have been used as bioindicators of air quality. They are sensitive to changes in air composition at any given site affecting their abundance, biomass and vitality.This study evaluated lichen affectation as a consequence of air pollution. Two study areas within the Aburra Valley and the RedAire network were selected: Miguel Aguinaga (high pollution station) and the Medellin University (low pollution station). Four phorophytic tree species were chosen at each site Terminalia catappa Linneaus, Eritrina fusca Loureiro, Mangifera indica Linneaus y Fraxinus chinensis Roxb. The lichen cover by species, the vitality and the fructification were used to analyze the effect of air pollution. Finally, the lichen cover information was used to calculate the index of atmospheric purity (IAP) and the Q factor determination. Total qualitative and quantitative information obtained made evident that Canoparmelia sp. and Parmotrema austrosinensis (Zahlbr) Hale. lichen species are the most sensitive, and therefore appropriate to assess air quality. Additionally, the statistical analysis carried out using the relative abundances by phorophytic trees, showed that Fraxinus chinensis Roxb is the most appropriate tree species for bioindicator lichens studies into the Aburra valley.

Nondestructive determination of the modulus of elasticity of Fraxinus mandschurica using near-infrared spectroscopy

Science.gov (United States)

Yu, Huiling; Liang, Hao; Lin, Xue; Zhang, Yizhuo

2018-04-01

A nondestructive methodology is proposed to determine the modulus of elasticity (MOE) of Fraxinus mandschurica samples by using near-infrared (NIR) spectroscopy. The test data consisted of 150 NIR absorption spectra of the wood samples obtained using an NIR spectrometer, with the wavelength range of 900 to 1900 nm. To eliminate the high-frequency noise and the systematic variations on the baseline, Savitzky-Golay convolution combined with standard normal variate and detrending transformation was applied as data pretreated methods. The uninformative variable elimination (UVE), improved by the evolutionary Monte Carlo (EMC) algorithm and successive projections algorithm (SPA) selected three characteristic variables from full 117 variables. The predictive ability of the models was evaluated concerning the root-mean-square error of prediction (RMSEP) and coefficient of determination (Rp2) in the prediction set. In comparison with the predicted results of all the models established in the experiments, UVE-EMC-SPA-LS-SVM presented the best results with the smallest RMSEP of 0.652 and the highest Rp2 of 0.887. Thus, it is feasible to determine the MOE of F. mandschurica using NIR spectroscopy accurately.

Emerald ash borer flight potential

Science.gov (United States)

Robin A. Taylor; Leah S. Bauer; Deborah L. Miller; Robert A. Haack

2005-01-01

The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive pest of ash trees (Fraxinus spp.) that is rapidly spreading from the probable introduction site in Detroit, Michigan. The rapid spread to areas outside Michigan is undoubtedly due to phoretic transport on nursery stock, logs, and...

Progress on biological control of emerald ash borer

Science.gov (United States)

Leah S. Bauer; Houping Liu; Juli Gould

2008-01-01

The emerald ash borer (EAB), Agrilus planipennis, a buprestid native to northeastern Asia, was determined as the cause of ash tree (Fraxinus spp.) mortality in areas of southern Michigan and Ontario, Canada, in 2002. Infestations have been found since in Ohio, Indiana, Maryland, Virginia, Illinois, Pennsylvania, and West Virginia....

Emerald Ash Borer Pest Alert, (English version)El barrenador del fresno, el barrenador verde esmeralda del fresno o (Spanish version)

Science.gov (United States)

Deborah McCullough; Steven Katovich

2008-01-01

A beetle from Asia, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), was identified in July 2002 as the cause of widespread ash (Fraxinus spp.) tree decline and mortality in southeastern Michigan and Windsor, Ontario, Canada. Larval feeding in the tissue between the bark and sapwood disrupts transport of nutrients and...

Emerald ash borer biological control

Science.gov (United States)

Leah Bauer; Juli Gould; Jian Duan; Mike. Ulyshen

2011-01-01

Emerald ash borer (EAB) (Agrilus planipennis), an invasive buprestid from northeast Asia, was identified in 2002 as the cause of ash (Fraxinus) tree mortality in southeast Michigan and adjacent areas of Ontario, Canada. This destructive beetle apparently arrived in North America via infested solid wood packaging materials from...

Susceptibility of two hymenopteran parasitoids of Agrilus planipennis (Coleoptera: Buprestidae) to the entomopathogenic fungus Beauveria bassiana (Ascomycota: Hypocreales)

Science.gov (United States)

Kimberly M Dean; John D. Vandenberg; Michael H. Griggs; Leah S. Bauer; Melissa K. Fierke

2012-01-01

Emerald ash borer (EAB), Agrilus planipennis Fairmaire, native to Asia, is killing ash trees (Fraxinus spp.) across 15 states and southeastern Canada. Integrated pest management using biological control is the only viable long-term approach for controlling the spread of EAB outside of host resistance. Three hymenopteran parasitoids...

Microsatellite population genetics of the emerald ash borer (Agrilus planipennis Fairmaire): comparisons between Asian and North American populations

Science.gov (United States)

Carson C. Keever; Christal Nieman; Larissa Ramsay; Carol E. Ritland; Leah S. Bauer; D. Barry Lyons; Jenny S. Cory

2013-01-01

The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) (Coleoptera; Buprestidae), is an invasive wood-boring beetle native to northeast Asia. This species was first detected in Michigan USA in 2002, and is a significant threat to native and ornamental ash tree species (Fraxinus spp.) throughout North America. We...

Hydroxyframoside B, a secoiridoid of Fraxinus rhynchophylla, inhibits adipocyte differentiation in 3T3-L1 cells.

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Choi, Kyeong-Mi; Shin, Eunjin; Liu, Qing; Yoo, Hwan-Soo; Kim, Young Choong; Sung, Sang Hyun; Hwang, Bang Yeon; Lee, Mi Kyeong

2011-07-01

Fraxinus rhynchophylla showed significant inhibitory activity on adipocyte differentiation in the 3T3-L1 preadipocyte cell line as assessed by measuring fat accumulation using Oil Red O staining. Further fractionation led to the isolation of two secoiridoids, oleuropein and hydroxyframoside B. Hydroxyframoside B significantly reduced fat accumulation and triglyceride content in differentiated 3T3-L1 cells without affecting cell viability, whereas oleuropein showed little effect. Further studies with interval treatment demonstrated that hydroxyframoside B exerted inhibitory activity on adipocyte differentiation when treated within 2 days (days 0-2) after differentiation induction. In addition, hydroxyframoside B significantly blocked the induction of adipogenic transcription factors such as C/EBP α, C/EBP β, and PPAR γ. Taken together, these results suggest that hydroxyframoside B inhibited early/middle stage of adipogenic differentiation, in part, via inhibition of C/EBP α, C/EBP β, and PPAR γ-dependent pathways. © Georg Thieme Verlag KG Stuttgart · New York.

Quantifying change in riparian ash forests following the introduction of EAB in Michigan and Indiana

Science.gov (United States)

Susan J. Crocker; Dacia M. Meneguzzo

2012-01-01

The emerald ash borer (Agrilus planipennis Fairmaire; Coleoptera: Buprestidae; EAB) is an introduced beetle that kills ash (Fraxinus spp.) trees. While most EAB-related ash mortality has been documented in urban areas, the effects of EAB in forested settings, particularly in riparian forests, are not well known. This study utilizes...

The Role of Windbreaks in Attracting the Useful Avifauna – Case Study: Moara Domnească Didactic Farm

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Cosmin Alexandru MIHAI

2018-05-01

Full Text Available “Moara Domnească” is a didactic farm belonging to the University of Agronomic Sciences and Veterinary Medicine of Bucharest. Moara Domnească has an area of 520 ha, of which 65 ha of orchard. The orchard, but also a major part of the farm has a wind protection system consisting of windbreaks planted in 1920’s with English Oak (Quercus robur, Ash (Fraxinus excelsior, Norway Maple (Acer platanoides, and other species of shrubs from the spontaneous flora. Since 1860, Romania has become one of the first countries in the world to have developed forest windbreaks and shelterbelt. Both the establishment of windbreaks and scientific research have been specifically designed to limit the negative effects of the extreme continental climate. Even the windbreaks benefits are multiple and clear, their extension was limited in many areas where are extremely needed. Based on the ornithological observations carried out between 2015-2016, we found out that the forest windbreak plays an extremely important role on the orchard ecosystem, influencing positively the life of wild birds that find food, shelter and nesting places throughout the year.

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

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Jake E Simpson

Full Text Available 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.

Emerald ash borer survival in firewood

Science.gov (United States)

Robert A. Haack; Toby R. Petrice

2005-01-01

The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is native to Asia and was first discovered in Michigan and Ontario in 2002. As of October 2004, EAB was only found to breed in ash (Fraxinus) trees in North America. EAB is spreading naturally through adult flight as well as artificially through...

Evaluating the economic costs and benefits of slowing the spread of emerald ash borer in Ohio and Michigan

Science.gov (United States)

Jonathan Bossenbroek; Audra Croskey; David Finnoff; Louis Iverson; Shana M. McDermott; Anantha Prasad; Charles Sims; Davis. Sydnor

2015-01-01

The emerald ash borer (Agrilus planipennis; EAB) is poised to wipe out native ashes (Fraxinus spp.) in North America with expected catastrophic losses to ash tree forestry (MacFarlane and Meyer 2005). EAB was first discovered in Detroit in 2002. Most scientists hypothesize that it entered the United States through solid wood...

Exploring the molecular and biochemical basis of ash resistance to emerald ash borer

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Justin G.A. Whitehill; Daniel A. Herms; Pierluigi. Bonello

2010-01-01

Larvae of the emerald ash borer (EAB) (Agrilus planipennis) feed on phloem of ash (Fraxinus spp.) trees. It is hypothesized that the resistance of Asian species of ash (e.g., Manchurian ash, F. mandshurica) to EAB is due to endogenous defenses present in phloem tissues in the form of defensive proteins and/or...

Emerald ash borer biology and invasion history

Science.gov (United States)

Robert A. Haack; Yuri Baranchikov; Leah S. Bauer; Therese M. Poland

2015-01-01

The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is native to eastern Asia and is primarily a pest of ash (Fraxinus) trees (Fig. 1). Established populations of EAB were first detected in the United States and Canada in 2002 (Haack et al., 2002), and based on a dendrochronology study by Siegert...

Thermal constraints on the emerald ash borer invasion of North America

Science.gov (United States)

DeSantis, R.; Moser, W. K.; Gormanson, D. D.; Bartlett, M. G.

2012-12-01

Emerald ash borer (Agrilus planipennis Fairmaire; EAB), a non-native invasive beetle, has caused substantial damage to green (Fraxinus pennsylvanica Marsh.), white (Fraxinus americana L.), and black ash (Fraxinus nigra Marsh.), the major ash species of North America. In the absence of effective methods for controlling or eradicating the beetle, EAB continues to spread unimpeded across North America. Evidence indicates the mortality rate for EAB-infested trees near the epicenter of the infestation in southeast Michigan exceeds 99 percent for the major ash species. One possible climatic limitation on the spread of the infestation is suggested by recent work indicating that beetles cannot survive exposure to temperatures below -35.3 degrees Celsius. We considered whether this thermal constraint will limit the spread and distribution of EAB in North America. Historical climatic data for the United States and Canada were employed along with thermal models of the conditions beneath likely winter snowpack and beneath tree bark to predict the potential geographic distribution of the invasion. Results suggested the thermal mortality constraint will not lead to the protection of ash stands across most of North America. However, recent work indicates the majority of beetles cannot survive exposure to temperatures below -30 degrees Celsius. Along with our results, this suggests thermal constraints near the northern and western edges of the ranges of ash might limit EAB survival to some extent, thereby reducing the EAB population, the likelihood of EAB infestation, and subsequent ash mortality.

Biological control of emerald ash borer in North America: current progress and potential for success

Science.gov (United States)

Jian J. Duan; Leah S. Bauer; Juli R. Gould; Jonathan P. Lelito

2012-01-01

The emerald ash borer (EAB) (Agrilus planipennis), a buprestid native to north-east Asia, was first discovered in North America near Detroit in 2002. EAB has since spread to at least 15 U.S. States and two Canadian provinces, threatening the existence of native ash trees (Fraxinus spp.). A classical biocontrol program was initiated...

Categorizing ideas about trees: a tree of trees.

Science.gov (United States)

Fisler, Marie; Lecointre, Guillaume

2013-01-01

The aim of this study is to explore whether matrices and MP trees used to produce systematic categories of organisms could be useful to produce categories of ideas in history of science. We study the history of the use of trees in systematics to represent the diversity of life from 1766 to 1991. We apply to those ideas a method inspired from coding homologous parts of organisms. We discretize conceptual parts of ideas, writings and drawings about trees contained in 41 main writings; we detect shared parts among authors and code them into a 91-characters matrix and use a tree representation to show who shares what with whom. In other words, we propose a hierarchical representation of the shared ideas about trees among authors: this produces a "tree of trees." Then, we categorize schools of tree-representations. Classical schools like "cladists" and "pheneticists" are recovered but others are not: "gradists" are separated into two blocks, one of them being called here "grade theoreticians." We propose new interesting categories like the "buffonian school," the "metaphoricians," and those using "strictly genealogical classifications." We consider that networks are not useful to represent shared ideas at the present step of the study. A cladogram is made for showing who is sharing what with whom, but also heterobathmy and homoplasy of characters. The present cladogram is not modelling processes of transmission of ideas about trees, and here it is mostly used to test for proximity of ideas of the same age and for categorization.

Dendrochronological reconstruction of the epicenter and early spread of emerald ash borer in North America

Science.gov (United States)

Nathan W. Siegert; Deborah G. McCullough; Andrew M. Liebhold; Frank W. Telewski

2014-01-01

Emerald ash borer Agrilus planipennis was identified in 2002 as the cause of extensive ash (Fraxinus spp.) decline and mortality in Detroit, Michigan, and has since killed millions of ash trees in the US and Canada. When discovered, it was not clear how long it had been present or at what location the invading colony started....

Hepatoprotective standardized EtOH-water extract from the seeds of Fraxinus rhynchophylla Hance.

Science.gov (United States)

Guo, Sen; Guo, Tiantian; Cheng, Ni; Liu, Qingchao; Zhang, Yunting; Bai, Lu; Zhang, Li; Cao, Wei; Ho, Chi-Tang; Bai, Naisheng

2017-04-01

Fraxinus rhynchophylla Hance (Oleaceae), its stem barks are known as Cortex fraxini ( qín pí) listed in Chinese Pharmacopoeia. Phytochemical study has indicated that methanol extracts from Qinpi has protective effect on acute liver injury. The present study investigates the hepatoprotective activity of EtOH-water extract from the seeds of F. rhynchophylla Hance against carbon tetrachloride-induced liver injury in mice. The EtOH-water extract significantly alleviated liver damage as indicated by the decreased levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), the malondialdehyde (MDA) content, and increased the levels of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GSH-Px), and reduced the pathological tissue injury induced by CCl 4 . Quantitative analysis of seven major constituents ( 1-7 ) in EtOH-water extract (EWE) was developed by high performance liquid chromatography-diode-array detector (HPLC-DAD). The current research indicates that the EWE from the seeds of F. rhynchophylla Hance decreased liver index, inhibited the increase of serum aminotransferase induced by CCl 4 , and decreased hepatic MDA content, SOD and GSH-Px activities. These results suggested that the pretreatment with EWE protected mice against CCl 4 -induced liver injuries. Based on the results, the EtOH-water extract from the seeds of F. rhynchophylla Hance is efficacious for prevention and treatment of CCl 4 -induced hepatic injury in mice. Secoiridoid and tyrosol glucosides might be the active ingredients responsible for the biological and pharmacological activities of hepatoprotection.

Syringin from stem bark of Fraxinus rhynchophylla protects Abeta(25-35)-induced toxicity in neuronal cells.

Science.gov (United States)

Yang, Eun-Ju; Kim, Sang-In; Ku, Hyun-Yeong; Lee, Dong-Seok; Lee, Jong-Won; Kim, Yae-Sil; Seong, Yeon-Hee; Song, Kyung-Sik

2010-04-01

The medicinal herb Jinpi, derived from the dried stem barks of Fraxinus rhynchophylla belonging to Oleaceae is widely used as a variety of Korean folk remedies for anti-inflammatory, febricide, antidiarrhea, and antileukorrhea diseases. In the course of screening antidementia agents from natural products, F. rhynchophylla showed significant inhibitory activity toward Abeta(25-35)-induced neuronal cell death. An active principle was isolated and identified as syringin. When the neuroblastoma cells were exposed to 50 microM Abeta(25-35), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction rate (survival rate) decreased to 60.21 +/- 2.16% over control while syringin treated ones recovered cell viability up to 79.12 +/- 1.39% at 20 microM. In addition, 20 microM syringin almost completely removed Abeta(25-35)-induced reactive oxygen species. The neuroprotective effect of syringin seemed to be originated from the reduction of apoptosis since decrease in caspase-3 activity and expression, reduction in cleaved PARP, and DNA fragmentation were observed. These results suggest that F. rhynchophylla and syringin are expected to be useful for preventing Abeta(25-35)-induced neuronal cell damage.

Effects of host plant and larval density on intraspecific competition in larvae of the emerald ash borer (Coleoptera: Buprestidae).

Science.gov (United States)

Duan, Jian J; Larson, Kristi; Watt, Tim; Gould, Juli; Lelito, Jonathan P

2013-12-01

Competition for food, mates, and space among different individuals of the same insect species can affect density-dependent regulation of insect abundance or population dynamics. The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of North American ash (Fraxinus spp.) trees, with its larvae feeding in serpentine galleries between the interface of sapwood and phloem tissues of ash trees. Using artificial infestation of freshly cut logs of green ash (Fraxinus pennsylvanica Marshall) and tropical ash (Fraxinus uhdei [Wenzig] Lingelsh) with a series of egg densities, we evaluated the mechanism and outcome of intraspecific competition in larvae of A. planipennis in relation to larval density and host plant species. Results from our study showed that as the egg densities on each log (1.5-6.5 cm in diameter and 22-25 cm in length) increased from 200 to 1,600 eggs per square meter of surface area, larval survivorship declined from ≍68 to 10% for the green ash logs, and 86 to 55% for tropical ash logs. Accordingly, larval mortality resulting from cannibalism, starvation, or both, significantly increased as egg density increased, and the biomass of surviving larvae significantly decreased on both ash species. When larval density was adjusted to the same level, however, larval mortality from intraspecific competition was significantly higher and mean biomasses of surviving larvae was significantly lower in green ash than in tropical ash. The role of intraspecific competition of A. planipennis larvae in density-dependent regulation of its natural population dynamics is discussed.

[Simulating climate change effect on aboveground carbon sequestration rates of main broadleaved trees in the Xiaoxing'an Mountains area, Northeast China].

Science.gov (United States)

Ma, Jun; Bu, Rencang; Deng, Hua-Wei; Hu, Yuan-Man; Qin, Qin; Han, Feng-Lin

2014-09-01

LANDIS Pro 7.0 model was used to simulate the dynamics of aboveground biomass of ten broadleaved tree species in the Xiao Xing' an Mountains area under current and various climate change scenarios from 2000 to 2200, and carbon content coefficients (CCCs) were coupled to cal- culate the aboveground carbon sequestration rates (ACSRs) of these species. The results showed that in the initial year of simulation, the biomasses and their proportions of Fraxinus mandshurica, Phellodendron amurense, Quercus mongolica, Ulmus propinqua, and Acer mono were relatively low, while those of Betula costata, Betula platyphylla, and Populus davidiana were higher. A trend of rise after decline occurred in ACSR for pioneer species in the mid and late periods of simulation years, but ACSRs for the other broadleaved tree species were considerably complex. The ACSRs of Q. mongolica and Tilla amurensis fluctuated in the ranges of -0.05-0.25 t · hm(-2) · 10 a(-1) and 0.16-1.29 t · hm(-2) · 10 a(-1) in simulation years, respectively. The ACSRs of F. mandshurica, U. propinqua, A. mono, and B. costata showed a trend of decline after rise in late simulation years. There were significant differences in ACSR for P. amurense and B. davurica among various climate change scenarios in the periods of 2050-2100 and 2150-2200, while no significant difference in ACSR for the other species would be detected. Difference of sensitivity of various species in ACSR for future climate scenarios in the Small Khingan Mountains area existed. However, the un- certainty of future climates would not yield significant difference in ACSR for most broadleaved tree species. Moreover, a time lag would exist in the process of climate change effects on temperate forest's ACSR.

Characterization of particulate matter deposited on urban tree foliage: A landscape analysis approach

Science.gov (United States)

Lin, Lin; Yan, Jingli; Ma, Keming; Zhou, Weiqi; Chen, Guojian; Tang, Rongli; Zhang, Yuxin

2017-12-01

Plants can mitigate ambient particulate matter by cleaning the air, which is crucial to urban environments. A novel approach was presented to quantitatively characterize particulate matter deposited on urban tree foliage. This approach could accurately quantify the number, size, shape, and spatial distribution of particles with different diameters on leaves. Spatial distribution is represented by proximity, which measures the closeness of particles. We sampled three common broadleaf species and obtained images through field emission scanning electron microscopy. We conducted the object-based method to extract particles from images. We then used Fragstats to analyze the landscape characteristics of these particles in term of selected metrics. Results reveal that Salix matsudana is more efficient than Ailanthus altissima and Fraxinus chinensis in terms of the number and area of particles per unit area and the proportion of fine particulate matter. The shape complexity of the particles increases with their size. Among the three species, S. matsudana and A. altissima particles respectively yield the highest and lowest proximity. PM1 in A. altissima and PM10 in F. chinensis and S. matsudana show the highest proximity, which may influence subsequent particle retention. S. matsudana should be generally considered to collect additional small particles. Different species and particle sizes exhibit various proximities, which should be further examined to elucidate the underlying mechanism.

Polyphenolic profile as a useful tool to identify the wood used in wine aging.

Science.gov (United States)

Sanz, Miriam; Fernández de Simón, Brígida; Cadahía, Estrella; Esteruelas, Enrique; Muñoz, Angel Ma; Hernández, Ma Teresa; Estrella, Isabel

2012-06-30

Although oak wood is the main material used in cooperage, other species are being considered as possible sources of wood for the production of wines and their derived products. In this work we have compared the phenolic composition of acacia (Robinia pseudoacacia), chestnut (Castanea sativa), cherry (Prunus avium) and ash (Fraxinus excelsior and F. americana) heartwoods, by using HPLC-DAD/ESI-MS/MS (some of these data have been showed in previous paper), as well as the changes that toasting intensity at cooperage produce in each polyphenolic profile. Before toasting, each wood shows a different and specific polyphenolic profile, with both qualitative and quantitative differences among them. Toasting notably changed these profiles, in general, proportionally to toasting intensity and led to a minor differentiation among species in toasted woods, although we also found phenolic markers in toasted woods. Thus, methyl syringate, benzoic acid, methyl vanillate, p-hydroxybenzoic acid, 3,4,5-trimethylphenol and p-coumaric acid, condensed tannins of the procyanidin type, and the flavonoids naringenin, aromadendrin, isosakuranetin and taxifolin will be a good tool to identify cherry wood. In acacia wood the chemical markers will be the aldehydes gallic and β-resorcylic and two not fully identified hydroxycinnamic compounds, condensed tannins of the prorobinetin type, and when using untoasted wood, dihydrorobinetin, and in toasted acacia wood, robinetin. In untoasted ash wood, the presence of secoiridoids, phenylethanoid glycosides, or di and oligolignols will be a good tool, especially oleuropein, ligstroside and olivil, together verbascoside and isoverbascoside in F. excelsior, and oleoside in F. americana. In toasted ash wood, tyrosol, syringaresinol, cyclolovil, verbascoside and olivil, could be used to identify the botanical origin. In addition, in ash wood, seasoned and toasted, neither hydrolysable nor condensed tannins were detected. Lastly, in chestnut wood, gallic

Six-Year Nitrogen–Water Interaction Shifts the Frequency Distribution and Size Inequality of the First-Order Roots of Fraxinus mandschurica in a Mixed Mature Pinus koraiensis Forest

Science.gov (United States)

Wang, Cunguo; Geng, Zhenzhen; Chen, Zhao; Li, Jiandong; Guo, Wei; Zhao, Tian-Hong; Cao, Ying; Shen, Si; Jin, Daming; Li, Mai-He

2017-01-01

The variation in fine root traits in terms of size inequality at the individual root level can be identified as a strategy for adapting to the drastic changes in soil water and nutrient availabilities. The Gini and Lorenz asymmetry coefficients have been applied to describe the overall degree of size inequality, which, however, are neglected when conventional statistical means are calculated. Here, we used the Gini coefficient, Lorenz asymmetry coefficient and statistical mean in an investigation of Fraxinus mandschurica roots in a mixed mature Pinus koraiensis forest on Changbai Mountain, China. We analyzed 967 individual roots to determine the responses of length, diameter and area of the first-order roots and of branching intensity to 6 years of nitrogen addition (N), rainfall reduction (W) and their combination (NW). We found that first-order roots had a significantly greater average length and area but had smaller Gini coefficients in NW plots compared to in control plots (CK). Furthermore, the relationship between first-order root length and branching intensity was negative in CK, N, and W plots but positive in NW plots. The Lorenz asymmetry coefficient was >1 for the first-order root diameter in NW and W plots as well as for branching intensity in N plots. The bimodal frequency distribution of the first-order root length in NW plots differed clearly from the unimodal one in CK, N, and W plots. These results demonstrate that not only the mean but also the variation and the distribution mode of the first-order roots of F. mandschurica respond to soil nitrogen and water availability. The changes in size inequality of the first-order root traits suggest that Gini and Lorenz asymmetry coefficients can serve as informative parameters in ecological investigations of roots to improve our ability to predict how trees will respond to a changing climate at the individual root level. PMID:29018474

Six-Year Nitrogen-Water Interaction Shifts the Frequency Distribution and Size Inequality of the First-Order Roots of Fraxinus mandschurica in a Mixed Mature Pinus koraiensis Forest.

Science.gov (United States)

Wang, Cunguo; Geng, Zhenzhen; Chen, Zhao; Li, Jiandong; Guo, Wei; Zhao, Tian-Hong; Cao, Ying; Shen, Si; Jin, Daming; Li, Mai-He

2017-01-01

The variation in fine root traits in terms of size inequality at the individual root level can be identified as a strategy for adapting to the drastic changes in soil water and nutrient availabilities. The Gini and Lorenz asymmetry coefficients have been applied to describe the overall degree of size inequality, which, however, are neglected when conventional statistical means are calculated. Here, we used the Gini coefficient, Lorenz asymmetry coefficient and statistical mean in an investigation of Fraxinus mandschurica roots in a mixed mature Pinus koraiensis forest on Changbai Mountain, China. We analyzed 967 individual roots to determine the responses of length, diameter and area of the first-order roots and of branching intensity to 6 years of nitrogen addition (N), rainfall reduction (W) and their combination (NW). We found that first-order roots had a significantly greater average length and area but had smaller Gini coefficients in NW plots compared to in control plots (CK). Furthermore, the relationship between first-order root length and branching intensity was negative in CK, N, and W plots but positive in NW plots. The Lorenz asymmetry coefficient was >1 for the first-order root diameter in NW and W plots as well as for branching intensity in N plots. The bimodal frequency distribution of the first-order root length in NW plots differed clearly from the unimodal one in CK, N, and W plots. These results demonstrate that not only the mean but also the variation and the distribution mode of the first-order roots of F. mandschurica respond to soil nitrogen and water availability. The changes in size inequality of the first-order root traits suggest that Gini and Lorenz asymmetry coefficients can serve as informative parameters in ecological investigations of roots to improve our ability to predict how trees will respond to a changing climate at the individual root level.

Tree compression with top trees

DEFF Research Database (Denmark)

Bille, Philip; Gørtz, Inge Li; Landau, Gad M.

2013-01-01

We introduce a new compression scheme for labeled trees based on top trees [3]. Our compression scheme is the first to simultaneously take advantage of internal repeats in the tree (as opposed to the classical DAG compression that only exploits rooted subtree repeats) while also supporting fast...

Tree compression with top trees

DEFF Research Database (Denmark)

Bille, Philip; Gørtz, Inge Li; Landau, Gad M.

2015-01-01

We introduce a new compression scheme for labeled trees based on top trees. Our compression scheme is the first to simultaneously take advantage of internal repeats in the tree (as opposed to the classical DAG compression that only exploits rooted subtree repeats) while also supporting fast...

Generalising tree traversals and tree transformations to DAGs

DEFF Research Database (Denmark)

Bahr, Patrick; Axelsson, Emil

2017-01-01

We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead. The resul......We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead...... as the complementing theory with a number of examples....

Surface tree languages and parallel derivation trees

NARCIS (Netherlands)

Engelfriet, Joost

1976-01-01

The surface tree languages obtained by top-down finite state transformation of monadic trees are exactly the frontier-preserving homomorphic images of sets of derivation trees of ETOL systems. The corresponding class of tree transformation languages is therefore equal to the class of ETOL languages.

Oleuropein isolated from Fraxinus rhynchophylla inhibits glutamate-induced neuronal cell death by attenuating mitochondrial dysfunction.

Science.gov (United States)

Kim, Mi Hye; Min, Ju-Sik; Lee, Joon Yeop; Chae, Unbin; Yang, Eun-Ju; Song, Kyung-Sik; Lee, Hyun-Shik; Lee, Hong Jun; Lee, Sang-Rae; Lee, Dong-Seok

2017-04-27

Glutamate-induced neurotoxicity is related to excessive oxidative stress accumulation and results in the increase of neuronal cell death. In addition, glutamate has been reported to lead to neurodegenerative diseases, including Parkinson's and Alzheimer's diseases.It is well known that Fraxinus rhynchophylla contains a significant level of oleuropein (Ole), which exerts various pharmacological effects. However, the mechanism of neuroprotective effects of Ole is still poorly defined. In this study, we aimed to investigate whether Ole prevents glutamate-induced toxicity in HT-22 hippocampal neuronal cells. The exposure of the glutamate treatment caused neuronal cell death through an alteration of Bax/Bcl-2 expression and translocation of mitochondrial apoptosis-inducing factor (AIF) to the cytoplasm of HT-22 cells. In addition, glutamate induced an increase in dephosphorylation of dynamin-related protein 1 (Drp1), mitochondrial fragmentation, and mitochondrial dysfunction. The pretreatment of Ole decreased Bax expression, increased Bcl-2 expression, and inhibited the translocation of mitochondrial AIF to the cytoplasm. Furthermore, Ole amended a glutamate-induced mitochondrial dynamic imbalance and reduced the number of cells with fragmented mitochondria, regulating the phosphorylation of Drp1 at amino acid residue serine 637. In conclusion, our results show that Ole has a preventive effect against glutamate-induced toxicity in HT-22 hippocampal neuronal cells. Therefore, these data imply that Ole may be an efficient approach for the treatment of neurodegenerative diseases.

Density of Emerald Ash Borer (Coleoptera: Buprestidae) Adults and Larvae at Three Stages of the Invasion Wave.

Science.gov (United States)

Burr, Stephen J; McCullough, Deborah G; Poland, Therese M

2018-02-08

Emerald ash borer (EAB) (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae), an invasive phloem-feeding buprestid, has killed hundreds of millions of ash (Fraxinus spp.) trees in the United States and two Canadian provinces. We evaluated EAB persistence in post-invasion sites and compared EAB adult captures and larval densities in 24 forested sites across an east-west gradient in southern Michigan representing the Core (post-invasion), Crest (high EAB populations), and Cusp (recently infested areas) of the EAB invasion wave. Condition of green ash (Fraxinus pennsylvanica Marsh) trees were recorded in fixed radius plots and linear transects in each site. Ash mortality was highest in Core sites in the southeast, moderate in Crest sites in central southern Michigan, and low in Cusp sites in the southwest. Traps and trap trees in Crest sites accounted for 75 and 60% of all EAB beetles captured in 2010 and 2011, respectively. Populations of EAB were present in all Core sites and traps in these sites captured 13% of all beetles each year. Beetle captures and larval densities at Cusp sites roughly doubled between 2010 and 2011, reflecting the increasing EAB populations. Sticky bands on girdled trees captured the highest density of EAB beetles per m2 of area, while baited double-decker traps had the highest detection rates and captured the most beetles. Larval densities were higher on girdled ash than on similar ungirdled trees and small planted trees. Woodpecker predation and a native larval parasitoid were present in all three invasion regions but had minor effects on ash survival and EAB densities. © The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

TreePics: visualizing trees with pictures

Directory of Open Access Journals (Sweden)

Nicolas Puillandre

2017-09-01

Full Text Available While many programs are available to edit phylogenetic trees, associating pictures with branch tips in an efficient and automatic way is not an available option. Here, we present TreePics, a standalone software that uses a web browser to visualize phylogenetic trees in Newick format and that associates pictures (typically, pictures of the voucher specimens to the tip of each branch. Pictures are visualized as thumbnails and can be enlarged by a mouse rollover. Further, several pictures can be selected and displayed in a separate window for visual comparison. TreePics works either online or in a full standalone version, where it can display trees with several thousands of pictures (depending on the memory available. We argue that TreePics can be particularly useful in a preliminary stage of research, such as to quickly detect conflicts between a DNA-based phylogenetic tree and morphological variation, that may be due to contamination that needs to be removed prior to final analyses, or the presence of species complexes.

Ecological Baseline, Fort Hood, Texas

Science.gov (United States)

1980-08-01

cedar eTm (Uiimus crassifolia), Texas ash (Fraxinus texansis), and Texas persimmon ( Diospyros texana). Conversely, the two predominant tree species...Ilex decidua), Mex- ican buckeye (Ungnadia spjeciosa), and Texas persimmon ( Diospyros texana). Vines included greenbrier (Smilax bona-nox) and white...Hedgehey Cactus (Echinocereus sp.) has been observed on Fort Hood. Due to the brief period of flowering for this genus , the individual species were not

The Buffalo Creek Archaeological Project. Volume 1: Background and Testing at 3MS346 and 3CG847 Mississippi and Craighead Counties, Arkansas

Science.gov (United States)

1992-01-01

shagbark hickory ( Carya ovata), and pecan ( Carya illinoensis ). These trees dominate the vegetation on well-drained elevated land such as tho-se areas...strongly acidic soil (Steyermark 1959:95, 120). Chinquapin (Castanea ozarkensis), black or sourgum (Nyssa sylvatica), black hickory ( Carya texana...white oak, mockernut hickory ( Carya tomentosa), black hickory, white hickory ( Carya alba), flowering dogwoo-T-,whiT𔃻eFash(Fraxinus americana

ColorTree: a batch customization tool for phylogenic trees.

Science.gov (United States)

Chen, Wei-Hua; Lercher, Martin J

2009-07-31

Genome sequencing projects and comparative genomics studies typically aim to trace the evolutionary history of large gene sets, often requiring human inspection of hundreds of phylogenetic trees. If trees are checked for compatibility with an explicit null hypothesis (e.g., the monophyly of certain groups), this daunting task is greatly facilitated by an appropriate coloring scheme. In this note, we introduce ColorTree, a simple yet powerful batch customization tool for phylogenic trees. Based on pattern matching rules, ColorTree applies a set of customizations to an input tree file, e.g., coloring labels or branches. The customized trees are saved to an output file, which can then be viewed and further edited by Dendroscope (a freely available tree viewer). ColorTree runs on any Perl installation as a stand-alone command line tool, and its application can thus be easily automated. This way, hundreds of phylogenic trees can be customized for easy visual inspection in a matter of minutes. ColorTree allows efficient and flexible visual customization of large tree sets through the application of a user-supplied configuration file to multiple tree files.

Tree Colors: Color Schemes for Tree-Structured Data.

Science.gov (United States)

Tennekes, Martijn; de Jonge, Edwin

2014-12-01

We present a method to map tree structures to colors from the Hue-Chroma-Luminance color model, which is known for its well balanced perceptual properties. The Tree Colors method can be tuned with several parameters, whose effect on the resulting color schemes is discussed in detail. We provide a free and open source implementation with sensible parameter defaults. Categorical data are very common in statistical graphics, and often these categories form a classification tree. We evaluate applying Tree Colors to tree structured data with a survey on a large group of users from a national statistical institute. Our user study suggests that Tree Colors are useful, not only for improving node-link diagrams, but also for unveiling tree structure in non-hierarchical visualizations.

TreePOD: Sensitivity-Aware Selection of Pareto-Optimal Decision Trees.

Science.gov (United States)

Muhlbacher, Thomas; Linhardt, Lorenz; Moller, Torsten; Piringer, Harald

2018-01-01

Balancing accuracy gains with other objectives such as interpretability is a key challenge when building decision trees. However, this process is difficult to automate because it involves know-how about the domain as well as the purpose of the model. This paper presents TreePOD, a new approach for sensitivity-aware model selection along trade-offs. TreePOD is based on exploring a large set of candidate trees generated by sampling the parameters of tree construction algorithms. Based on this set, visualizations of quantitative and qualitative tree aspects provide a comprehensive overview of possible tree characteristics. Along trade-offs between two objectives, TreePOD provides efficient selection guidance by focusing on Pareto-optimal tree candidates. TreePOD also conveys the sensitivities of tree characteristics on variations of selected parameters by extending the tree generation process with a full-factorial sampling. We demonstrate how TreePOD supports a variety of tasks involved in decision tree selection and describe its integration in a holistic workflow for building and selecting decision trees. For evaluation, we illustrate a case study for predicting critical power grid states, and we report qualitative feedback from domain experts in the energy sector. This feedback suggests that TreePOD enables users with and without statistical background a confident and efficient identification of suitable decision trees.

Indicator species of essential forest tree species in the Burdur district.

Science.gov (United States)

Negiz, Mehmet Güvenç; Eser, Yunus; Kuzugüdenll, Emre; Izkan, Kürşad

2015-01-01

The forests of Burdur district for long have been subjected to over grazing and individual selection. As a result of this, majority of the forest areas in the district were degraded. In the district, afforestation efforts included majority of forestry implementations. It is well known that selecting suitable species plays an important role for achieving afforestation efforts. In this context, knowing the indicator species among the target species would be used in afforestation efforts, studies on the interrelationships between environmental factors and target species distribution is vital for selecting suitable species for a given area. In this study, Anatolian Black pine (Pinus nigra), Red pine (Pinus brutia), Crimean juniper (Juniperus excelsa) and Taurus cedar (Cedrus libani), essential tree species, were considered as target species. The data taken from 100 sample plots in Burdur district was used. Interspecific correlation analysis was performed to determine the positive and negative indicator species among each of the target species. As a result of ICA, 2 positive (Berberis crataegina, Juniperus oxycedrus), 2 negative (Phillyrea latifolia, Quercus coccifera) for Crimean Juniper, I positive (Juniperus oxycedrus), 3 negative (Onopordium acanthium, Fraxinus ornus, Phillyrea latifolia) for Anatolian black pine, 3 positive (Paliurus spina-christi, Quercus coccifer, Crataegus orientalis), 2 negative (Berberis crataegina, Astragalus nanus) for Red pine and 3 positive (Berberis crataegina, Rhamnus oleoides, Astragalus prusianus) 2 negative (Paliurus spina-christi, Quercus cerris) for Taurus cedarwere defined as indicator plant species. In this way, practical information was obtained for selecting the most suitable species, among the target species, for afforestation efforts in Burdur district.

Two Trees: Migrating Fault Trees to Decision Trees for Real Time Fault Detection on International Space Station

Science.gov (United States)

Lee, Charles; Alena, Richard L.; Robinson, Peter

2004-01-01

We started from ISS fault trees example to migrate to decision trees, presented a method to convert fault trees to decision trees. The method shows that the visualizations of root cause of fault are easier and the tree manipulating becomes more programmatic via available decision tree programs. The visualization of decision trees for the diagnostic shows a format of straight forward and easy understands. For ISS real time fault diagnostic, the status of the systems could be shown by mining the signals through the trees and see where it stops at. The other advantage to use decision trees is that the trees can learn the fault patterns and predict the future fault from the historic data. The learning is not only on the static data sets but also can be online, through accumulating the real time data sets, the decision trees can gain and store faults patterns in the trees and recognize them when they come.

Tree Nut Allergies

Science.gov (United States)

... Blog Vision Awards Common Allergens Tree Nut Allergy Tree Nut Allergy Learn about tree nut allergy, how ... a Tree Nut Label card . Allergic Reactions to Tree Nuts Tree nuts can cause a severe and ...

ERATOSTHENES: excellence research Centre for Earth surveillance and space-based monitoring of the environment, the EXCELSIOR Horizon 2020 teaming project

Science.gov (United States)

Hadjimitsis, Diofantos G.; Kontoes, Haris; Schreier, Gunter; Ansmann, Albert; Komodromos, George; Themistocleous, Kyriacos; Mamouri, Rodanthi; Michaelides, Silas; Nisantzi, Argyro; Papoutsa, Christiana; Neocleous, Kyriacos; Mettas, Christodoulos; Tzouvaras, Marios; Evagorou, Evagoras; Christofe, Andreas; Melillos, George; Papoutsis, Ioannis

2017-10-01

The aim of this paper is to present the strategy and vision to upgrade the existing ERATOSTHENES Research Centre (ERC) established within the Cyprus University of Technology (CUT) into a sustainable, viable and autonomous Centre of Excellence (CoE) for Earth Surveillance and Space-Based Monitoring of the Environment, which will provide the highest quality of related services on the National, European and International levels. EXCELSIOR is a Horizon 2020 Teaming project which addresses a specific challenge defined by the work program, namely, the reduction of substantial disparities in the European Union by supporting research and innovation activities and systems in low performing countries. It also aims at establishing long-term and strategic partnerships between the Teaming partners, thus reducing internal research and innovation disparities within European Research and Innovation landscape. The proposed CoE envisions the upgrading of the existing ERC into an inspiring environment for conducting basic and applied research and innovation in the areas of the integrated use of remote sensing and space-based techniques for monitoring the environment. Environment has been recognized by the Smart Specialization Strategy of Cyprus as the first horizontal priority for future growth of the island. The foreseen upgrade will regard the expansion of this vision to systematic monitoring of the environment using Earth Observation, space and ground based integrated technologies. Such an approach will lead to the systematic monitoring of all three domains of the Environment (Air, Land, Water). Five partners have united to upgrade the existing ERC into a CoE, with the common vision to become a world-class innovation, research and education centre, actively contributing to the European Research Area (ERA). More specifically, the Teaming project is a team effort between the Cyprus University of Technology (CUT, acting as the coordinator), the German Aerospace Centre (DLR), the

Fort Devens Feasibility Study for Group 1A Sites. Final Feasibility Study Shepley’s Hill Landfill Operable Unit Data Item A009

Science.gov (United States)

1995-02-01

WELL LOCATIONS MONITORING PARAMETERS SHL-3 Volatile Organic Compounds SHL-4 USEPA Method 624 plus acetone, 2-butanone, 2- methyl pentanone, and xylenes...pines ( Pinus strobus) in addition to red maple (Acer rubrum). The understory in this area contains american hazelnut, cinnamon fern, and3 clubmoss...NAME STATUS* Trees URed Maple Acer rubrum FAC Gray Birch Betula populifolia FAG Green Ash Fraxinus pennsylvanica FACW` Red Pine Pinus resinosa FACU White

Endangered Species Management Plan for Fort Hood, Texas: FY06-10

Science.gov (United States)

2007-05-01

Texas red oak, post oak, Texas ash (Fraxinus texensis), shin oak, blackjack oak (Quercus marilandica), slippery elm (Ulmus rubra), cedar elm ...by Ashe juniper and Texas oak. Other important tree species included live oak, cedar elm (Ulmus crassifolia), Lacey oak (Quercus laceyi), Arizona...0.83 m (Cimprich 2005). Nest substrates include shin oak, Texas red oak, Texas redbud, Ashe juniper, Texas ash, Plateau live oak, cedar elm , rusty

Big trees, old trees, and growth factor tables

Science.gov (United States)

Kevin T. Smith

2018-01-01

The potential for a tree to reach a great size and to live a long life frequently captures the public's imagination. Sometimes the desire to know the age of an impressively large tree is simple curiosity. For others, the date-of-tree establishment can make a big diff erence for management, particularly for trees at historic sites or those mentioned in property...

A Suffix Tree Or Not a Suffix Tree?

DEFF Research Database (Denmark)

Starikovskaya, Tatiana; Vildhøj, Hjalte Wedel

2015-01-01

In this paper we study the structure of suffix trees. Given an unlabeled tree r on n nodes and suffix links of its internal nodes, we ask the question “Is r a suffix tree?”, i.e., is there a string S whose suffix tree has the same topological structure as r? We place no restrictions on S, in part...

[Accumulation responses of seeds and seedlings to 15N isotope for two typical broadleaved trees in Northeast China.

Science.gov (United States)

Wang, Guang Chen; Song, Yuan; Yan, Qiao Ling; Zhang, Jin Xin

2016-08-01

Two typical broadleaved trees (i.e., Fraxinus rhynchophylla and Acer mono) with wind-dispersed seeds in Northeast China were selected in this study. A method of 15 N isotope labeling was used to explore the accumulation responses of seeds and seedlings to 15 N-urea soaking concentration (0, 0.05, 0.1 and 0.2 g·L -1 ), soaking time (4, 8 and 12 days) and leaf stage (2, 4, 6, and 8 leaves). The results showed that 15 N-urea soaking concentration and soaking time had significantly positive effects on δ 15 N values of seeds, i.e., higher 15 N-urea concentration and longer period of soaking (0.2 g·L -1 +12 d) were contributed to more 15 N accumulation of seeds. The maximum multiples of 15 N accumulation in F. rhynchophylla seeds and A. mono seeds were observed in 0.1 g·L -1 + (4 d, 8 d) and 0.05 g·L -1 + (4 d, 8 d), respectively. The loss rate of δ 15 N values decreased markedly from 2 leaves to 6 leaves and then kept relatively stable with the increasing seedling height, and the total δ 15 N values of seedlings started to decline at the stage of 8 leaves. These results suggested that seedlings with 6 leaves were more suitable for tracking seedling source. The δ 15 N values in leaves of seedlings were significantly positively correlated with 15 N-urea concentration level, soaking time and δ 15 N values of seeds. Overall, the accumulation of 15 N-urea could be found in seeds and seedlings of F. rhynchophylla and A. mono. The combination of 15 N-urea concentration (0.1 g·L -1 ), soaking time (8 d) and leaf stage (6 leaves) was the most suitable for tracking the seeds and seedlings of these two broadleaved trees.

Tree-growth analyses to estimate tree species' drought tolerance

NARCIS (Netherlands)

Eilmann, B.; Rigling, A.

2012-01-01

Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree

TreeNetViz: revealing patterns of networks over tree structures.

Science.gov (United States)

Gou, Liang; Zhang, Xiaolong Luke

2011-12-01

Network data often contain important attributes from various dimensions such as social affiliations and areas of expertise in a social network. If such attributes exhibit a tree structure, visualizing a compound graph consisting of tree and network structures becomes complicated. How to visually reveal patterns of a network over a tree has not been fully studied. In this paper, we propose a compound graph model, TreeNet, to support visualization and analysis of a network at multiple levels of aggregation over a tree. We also present a visualization design, TreeNetViz, to offer the multiscale and cross-scale exploration and interaction of a TreeNet graph. TreeNetViz uses a Radial, Space-Filling (RSF) visualization to represent the tree structure, a circle layout with novel optimization to show aggregated networks derived from TreeNet, and an edge bundling technique to reduce visual complexity. Our circular layout algorithm reduces both total edge-crossings and edge length and also considers hierarchical structure constraints and edge weight in a TreeNet graph. These experiments illustrate that the algorithm can reduce visual cluttering in TreeNet graphs. Our case study also shows that TreeNetViz has the potential to support the analysis of a compound graph by revealing multiscale and cross-scale network patterns. © 2011 IEEE

Species-Specific Morphological and Physiological Responses of Four Korean Native Trees Species under Elevated CO2 Concentration using Open Top Chamber

Science.gov (United States)

Song, W.; Byeon, S.; Lee, H.; Lee, M.; Lim, H.; Kim, H. S.

2017-12-01

For the last three years, studies on the morphological and physiological characteristics were carried out for four tree species (Pinus densiflora, Quercus acutissima, Sorbus alnifolia and Fraxinus rhynchophylla) which are representative native species of Korea. We used a control site and three open top chambers (con, chamber 1, 2, and 3) which were exposed to ambient and two elevated CO2 concentration ([CO2]); the concentration were the ambient (400ppm) for control and chamber 1 and 1.4 times (560ppm) and 1.8 times (720 ppm) of the atmosphere for chamber 2 and 3, respectively. Leaf mass per area (LMA), stomatal size, density and area were examined to investigate the morphological changes of the trees. Among four species, F. rhynchophylla increased their LMA with increase of CO2 concentration. In addition, F. rhynchophylla showed the decrease of stomatal density significantly (p-value=0.02), while there was no difference in stoma size. These findings resulted in 25.5% and 38.7% decrease of stomata area per unit leaf area calculated by multiplying the size and density of the stomata. On the other hand, all 4 tree species were significantly increased in height and diameter growth with the elevated CO2. However, in the case of Q. acutissima, the increase in height growth was prominent. For physiological characteristics, the maximum photosynthetic rate was faster in the chambers exposed to high [CO2] than that in the control. However the rate of carboxylation and the electron transfer rate showed no particular tendency. The measurement of hydraulic conductivity (Ks, kg/m/s/Mpa) for Crataegus pinnatifida, increased as the [CO2] in the atmosphere increased, and the 50% Loss Conductance (Mpa) tended to increase slightly with the [CO2]. The correlation analysis between hydraulic conductivity and vulnerability to cavitation showed a strong negative correlation (P <0.05), which was unlike the general tendency.

Effect of elevated atmospheric CO2 concentration on growth and leaf litter decomposition of Quercus acutissima and Fraxinus rhynchophylla.

Directory of Open Access Journals (Sweden)

Sangsub Cha

Full Text Available The atmospheric carbon dioxide (CO2 level is expected to increase substantially, which may change the global climate and carbon dynamics in ecosystems. We examined the effects of an elevated atmospheric CO2 level on the growth of Quercus acutissima and Fraxinus rhynchophylla seedlings. We investigated changes in the chemical composition of leaf litter, as well as litter decomposition. Q. acutissima and F. rhynchophylla did not show differences in dry weight between ambient CO2 and enriched CO2 treatments, but they exhibited different patterns of carbon allocation, namely, lower shoot/root ratio (S/R and decreased specific leaf area (SLA under CO2-enriched conditions. The elevated CO2 concentration significantly reduced the nitrogen concentration in leaf litter while increasing lignin concentrations and carbon/nitrogen (C/N and lignin/N ratios. The microbial biomass associated with decomposing Q. acutissima leaf litter was suppressed in CO2 enrichment chambers, while that of F. rhynchophylla was not. The leaf litter of Q. acutissima from the CO2-enriched chambers, in contrast with F. rhynchophylla, contained much lower nutrient concentrations than that of the litter in the ambient air chambers. Consequently, poorer litter quality suppressed decomposition.

Effect of elevated atmospheric CO2 concentration on growth and leaf litter decomposition of Quercus acutissima and Fraxinus rhynchophylla.

Science.gov (United States)

Cha, Sangsub; Chae, Hee-Myung; Lee, Sang-Hoon; Shim, Jae-Kuk

2017-01-01

The atmospheric carbon dioxide (CO2) level is expected to increase substantially, which may change the global climate and carbon dynamics in ecosystems. We examined the effects of an elevated atmospheric CO2 level on the growth of Quercus acutissima and Fraxinus rhynchophylla seedlings. We investigated changes in the chemical composition of leaf litter, as well as litter decomposition. Q. acutissima and F. rhynchophylla did not show differences in dry weight between ambient CO2 and enriched CO2 treatments, but they exhibited different patterns of carbon allocation, namely, lower shoot/root ratio (S/R) and decreased specific leaf area (SLA) under CO2-enriched conditions. The elevated CO2 concentration significantly reduced the nitrogen concentration in leaf litter while increasing lignin concentrations and carbon/nitrogen (C/N) and lignin/N ratios. The microbial biomass associated with decomposing Q. acutissima leaf litter was suppressed in CO2 enrichment chambers, while that of F. rhynchophylla was not. The leaf litter of Q. acutissima from the CO2-enriched chambers, in contrast with F. rhynchophylla, contained much lower nutrient concentrations than that of the litter in the ambient air chambers. Consequently, poorer litter quality suppressed decomposition.

TREE SELECTING AND TREE RING MEASURING IN DENDROCHRONOLOGICAL INVESTIGATIONS

Directory of Open Access Journals (Sweden)

Sefa Akbulut

2004-04-01

Full Text Available Dendrochronology is a method of dating which makes use of the annual nature of tree growth. Dendrochronology may be divided into a number of subfields, each of which covers one or more aspects of the use of tree ring data: dendroclimatology, dendrogeomorphology, dendrohydrology, dendroecology, dendroarchaelogy, and dendrogylaciology. Basic of all form the analysis of the tree rings. The wood or tree rings can aid to dating past events about climatology, ecology, geology, hydrology. Dendrochronological studies are conducted either on increment cores or on discs. It may be seen abnormalities on tree rings during the measurement like that false rings, missing rings, reaction wood. Like that situation, increment cores must be extracted from four different sides of each tree and be studied as more as on tree.

Visualizing Individual Tree Differences in Tree-Ring Studies

Directory of Open Access Journals (Sweden)

Mario Trouillier

2018-04-01

Full Text Available Averaging tree-ring measurements from multiple individuals is one of the most common procedures in dendrochronology. It serves to filter out noise from individual differences between trees, such as competition, height, and micro-site effects, which ideally results in a site chronology sensitive to regional scale factors such as climate. However, the climate sensitivity of individual trees can be modulated by factors like competition, height, and nitrogen deposition, calling attention to whether average chronologies adequately assess climatic growth-control. In this study, we demonstrate four simple but effective methods to visually assess differences between individual trees. Using individual tree climate-correlations we: (1 employed jitter plots with superimposed metadata to assess potential causes for these differences; (2 plotted the frequency distributions of climate correlations over time as heat maps; (3 mapped the spatial distribution of climate sensitivity over time to assess spatio-temporal dynamics; and (4 used t-distributed Stochastic Neighborhood Embedding (t-SNE to assess which trees were generally more similar in terms of their tree-ring pattern and their correlation with climate variables. This suite of exploratory methods can indicate if individuals in tree-ring datasets respond differently to climate variability, and therefore, should not solely be explored with climate correlations of the mean population chronology.

Incidence of bark- and wood-boring insects in firewood: a survey at Michigan's Mackinac Bridge.

Science.gov (United States)

Haack, Robert A; Petrice, Toby R; Wiedenhoeft, Alex C

2010-10-01

Firewood is a major pathway for the inadvertent movement of bark- and wood-infesting insects. After discovery of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) in southeastern Michigan in 2002, quarantines were enacted including prohibition of transporting firewood across the Mackinac Bridge between Michigan's Lower and Upper peninsulas. Drivers are required to surrender firewood before crossing the bridge. We surveyed recently surrendered firewood in April, July, and September 2008 and categorized it by genus, cross-sectional shape (whole, half, or quarter), approximate age (years since it was a live tree), presence of bark, and evidence of bark- and wood-boring insects. The 1045 pieces of firewood examined represented 21 tree genera: primarily Acer (30%), Quercus (18%), Fraxinus (15%), Ulmus (12%), Betula (5%), and Prunus (5%). Live borers (Bostrichoidea, Brentidae, Buprestidae, Cerambycidae, Cossidae, Curculionidae [Scolytinae and non-Scolytinae], and Siricidae) were found in 23% of the pieces and another 41% had evidence of previous borer infestation. Of the 152 Fraxinus firewood pieces, 13% had evidence of past A. planipennis infestation, but we found no live A. planipennis. We discuss national "don't move firewood" campaigns and U.S. imports of fuelwood. During 1996-2009, the United States imported fuelwood valued at > dollars U.S. 98 million from 34 countries.

Fault tree handbook

International Nuclear Information System (INIS)

Haasl, D.F.; Roberts, N.H.; Vesely, W.E.; Goldberg, F.F.

1981-01-01

This handbook describes a methodology for reliability analysis of complex systems such as those which comprise the engineered safety features of nuclear power generating stations. After an initial overview of the available system analysis approaches, the handbook focuses on a description of the deductive method known as fault tree analysis. The following aspects of fault tree analysis are covered: basic concepts for fault tree analysis; basic elements of a fault tree; fault tree construction; probability, statistics, and Boolean algebra for the fault tree analyst; qualitative and quantitative fault tree evaluation techniques; and computer codes for fault tree evaluation. Also discussed are several example problems illustrating the basic concepts of fault tree construction and evaluation

Esculetin from Fraxinus rhynchophylla attenuates atopic skin inflammation by inhibiting the expression of inflammatory cytokines.

Science.gov (United States)

Jeong, Na-Hee; Yang, Eun-Ju; Jin, Meiling; Lee, Jong Yeong; Choi, Young-Ae; Park, Pil-Hoon; Lee, Sang-Rae; Kim, Sun-Uk; Shin, Tae-Yong; Kwon, Taeg Kyu; Jang, Yong Hyun; Song, Kyung-Sik; Kim, Sang-Hyun

2018-06-01

Atopic dermatitis (AD) is a common chronic inflammatory skin disorder afflicting from infancy to adults with itching, scratching, and lichenification. We aimed to investigate the effects of esculetin from Fraxinus rhynchophylla on atopic skin inflammation. For induction of atopic skin inflammation, we exposed the ears of female BALB/c mice to house dust mite (Dermatophagoides farinae extract, DFE) and 2,4-dinitrochlorobenzene (DNCB) for 4 weeks. Oral administration of esculetin reduced the symptoms of DFE/DNCB-induced atopic skin inflammation, which were evaluated based on ear swelling and number of scratch bouts. The immunoglobulin (Ig) E, IgG2a, and histamine levels in serum were decreased and inflammatory cell infiltration in skin tissue was reduced by the esculetin. It suppressed production of Th1, Th2 and Th17-related cytokines such as tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-4, IL-13, IL-31 and IL-17 in the ear tissue. Furthermore, we investigated the effects of esculetin on activated keratinocytes, which are representative cells used for studying the pathogenesis of acute and chronic atopic skin inflammation. As results, esculetin suppressed gene expression of Th1, Th2 and Th17 cytokines and the activation of nuclear factor-κB and signal transducer and activator of transcription 1 in TNF-α/IFN-γ-stimulated keratinocytes. Taken together, these results imply that esculetin attenuated atopic skin inflammation, suggesting that esculetin could be a potential therapeutic candidate for the treatment of AD. Copyright © 2018 Elsevier B.V. All rights reserved.

Modular tree automata

DEFF Research Database (Denmark)

Bahr, Patrick

2012-01-01

Tree automata are traditionally used to study properties of tree languages and tree transformations. In this paper, we consider tree automata as the basis for modular and extensible recursion schemes. We show, using well-known techniques, how to derive from standard tree automata highly modular...

Rate of tree carbon accumulation increases continuously with tree size.

Science.gov (United States)

Stephenson, N L; Das, A J; Condit, R; Russo, S E; Baker, P J; Beckman, N G; Coomes, D A; Lines, E R; Morris, W K; Rüger, N; Alvarez, E; Blundo, C; Bunyavejchewin, S; Chuyong, G; Davies, S J; Duque, A; Ewango, C N; Flores, O; Franklin, J F; Grau, H R; Hao, Z; Harmon, M E; Hubbell, S P; Kenfack, D; Lin, Y; Makana, J-R; Malizia, A; Malizia, L R; Pabst, R J; Pongpattananurak, N; Su, S-H; Sun, I-F; Tan, S; Thomas, D; van Mantgem, P J; Wang, X; Wiser, S K; Zavala, M A

2014-03-06

Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations. Our ability to understand and predict changes in the forest carbon cycle--particularly net primary productivity and carbon storage--increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree, in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation) decrease, remain constant, or increase as trees increase in size and age. Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size. Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree. The apparent paradoxes of individual tree growth increasing with tree size despite declining leaf-level and stand-level productivity can be explained, respectively, by increases in a tree's total leaf area that outpace declines in productivity per unit of leaf area and, among other factors, age-related reductions in population density. Our results resolve conflicting assumptions about the nature of tree growth, inform efforts to undertand and model forest carbon dynamics, and have additional implications for theories of resource allocation and plant senescence.

SYNTAXONOMY OF HY GROPHILOUS WOODS OF THE ALNO-QUERCION ROBORIS

Directory of Open Access Journals (Sweden)

S. BRULLO

1999-01-01

Full Text Available A syntaxonomical revision of the hygrophilous woods occurring in marshy places of the flood-plains from SE Europe is given. This vegetation is included in the Alno-Quercion roboris, alliance of the Populetalia albae, which comprises numerous associations characterized by the dominance of hard-wood trees, such as Quercus robur, Fraxinus oxycarpa, Ulmus minor, Alnus glutinosa, etc. For each association the synonyms, nomenclature type, diagnostic species, ecology, structure and chorology are given.

Phenological behaviour of early spring flowering trees in Spain in response to recent climate changes

Science.gov (United States)

Hidalgo-Galvez, M. D.; García-Mozo, H.; Oteros, J.; Mestre, A.; Botey, R.; Galán, C.

2018-04-01

This research reports the phenological trends of four early spring and late winter flowering trees in Spain (south Europe) from a recent period (1986-2012). The studied species were deciduous trees growing in different climatic areas: hazel ( Corylus avellana L.), willow ( Salix alba L.), ash ( Fraxinus angustifolia Vahl.) and white mulberry ( Morus alba L.). We analysed the response to climate and the trends of the following phenophases observed at the field: budburst, leaf unfolding, flowering, fruit ripening, fruit harvesting, leaf colour change and leaf-fall. The study was carried out in 17 sampling sites in the country with the aim of detecting the recent phenological response to the climate of these species, and the possible effect of climate change. We have observed differences in the phenological response to climate depending on each species. Sixty-one percent of studied sites suffered an advance of early spring phenophases, especially budburst on average by -0.67 days and flowering on average by -0.15 days during the studied period, and also in the subsequent fruit ripening and harvesting phases on average by -1.06 days. By contrast, it has been detected that 63% of sampling sites showed a delay in autumn vegetative phases, especially leaf-fall events on average by +1.15 days. The statistic correlation analysis shows in the 55% of the studied localities that phenological advances are the consequence of the increasing trend detected for temperature—being minimum temperature the most influential factor—and in the 52% of them, phenological advances occurred by rainfall variations. In general, leaf unfolding and flowering from these species showed negative correlations in relation to temperature and rainfall, whereas that leaf colour change and leaf-fall presented positive correlations. The results obtained have a great relevance due to the fact that they can be considered as reliable bio-indicators of the impact of the recent climate changes in southern

A bijection between phylogenetic trees and plane oriented recursive trees

OpenAIRE

Prodinger, Helmut

2017-01-01

Phylogenetic trees are binary nonplanar trees with labelled leaves, and plane oriented recursive trees are planar trees with an increasing labelling. Both families are enumerated by double factorials. A bijection is constructed, using the respective representations a 2-partitions and trapezoidal words.

Rate of tree carbon accumulation increases continuously with tree size

Science.gov (United States)

Stephenson, N.L.; Das, A.J.; Condit, R.; Russo, S.E.; Baker, P.J.; Beckman, N.G.; Coomes, D.A.; Lines, E.R.; Morris, W.K.; Rüger, N.; Álvarez, E.; Blundo, C.; Bunyavejchewin, S.; Chuyong, G.; Davies, S.J.; Duque, Á.; Ewango, C.N.; Flores, O.; Franklin, J.F.; Grau, H.R.; Hao, Z.; Harmon, M.E.; Hubbell, S.P.; Kenfack, D.; Lin, Y.; Makana, J.-R.; Malizia, A.; Malizia, L.R.; Pabst, R.J.; Pongpattananurak, N.; Su, S.-H.; Sun, I-F.; Tan, S.; Thomas, D.; van Mantgem, P.J.; Wang, X.; Wiser, S.K.; Zavala, M.A.

2014-01-01

Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations. Our ability to understand and predict changes in the forest carbon cycle—particularly net primary productivity and carbon storage - increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree, in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation) decrease, remain constant, or increase as trees increase in size and age. Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size. Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree. The apparent paradoxes of individual tree growth increasing with tree size despite declining leaf-level and stand-level productivity can be explained, respectively, by increases in a tree’s total leaf area that outpace declines in productivity per unit of leaf area and, among other factors, age-related reductions in population density. Our results resolve conflicting assumptions about the nature of tree growth, inform efforts to understand and model forest carbon dynamics, and have additional implications for theories of resource allocation and plant senescence.

Spectral analysis of white ash response to emerald ash borer infestations

Science.gov (United States)

Calandra, Laura

The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) is an invasive insect that has killed over 50 million ash trees in the US. The goal of this research was to establish a method to identify ash trees infested with EAB using remote sensing techniques at the leaf-level and tree crown level. First, a field-based study at the leaf-level used the range of spectral bands from the WorldView-2 sensor to determine if there was a significant difference between EAB-infested white ash (Fraxinus americana) and healthy leaves. Binary logistic regression models were developed using individual and combinations of wavelengths; the most successful model included 545 and 950 nm bands. The second half of this research employed imagery to identify healthy and EAB-infested trees, comparing pixel- and object-based methods by applying an unsupervised classification approach and a tree crown delineation algorithm, respectively. The pixel-based models attained the highest overall accuracies.

IcyTree: rapid browser-based visualization for phylogenetic trees and networks.

Science.gov (United States)

Vaughan, Timothy G

2017-08-01

IcyTree is an easy-to-use application which can be used to visualize a wide variety of phylogenetic trees and networks. While numerous phylogenetic tree viewers exist already, IcyTree distinguishes itself by being a purely online tool, having a responsive user interface, supporting phylogenetic networks (ancestral recombination graphs in particular), and efficiently drawing trees that include information such as ancestral locations or trait values. IcyTree also provides intuitive panning and zooming utilities that make exploring large phylogenetic trees of many thousands of taxa feasible. IcyTree is a web application and can be accessed directly at http://tgvaughan.github.com/icytree . Currently supported web browsers include Mozilla Firefox and Google Chrome. IcyTree is written entirely in client-side JavaScript (no plugin required) and, once loaded, does not require network access to run. IcyTree is free software, and the source code is made available at http://github.com/tgvaughan/icytree under version 3 of the GNU General Public License. tgvaughan@gmail.com. © The Author(s) 2017. Published by Oxford University Press.

TreeScaper: Visualizing and Extracting Phylogenetic Signal from Sets of Trees.

Science.gov (United States)

Huang, Wen; Zhou, Guifang; Marchand, Melissa; Ash, Jeremy R; Morris, David; Van Dooren, Paul; Brown, Jeremy M; Gallivan, Kyle A; Wilgenbusch, Jim C

2016-12-01

Modern phylogenomic analyses often result in large collections of phylogenetic trees representing uncertainty in individual gene trees, variation across genes, or both. Extracting phylogenetic signal from these tree sets can be challenging, as they are difficult to visualize, explore, and quantify. To overcome some of these challenges, we have developed TreeScaper, an application for tree set visualization as well as the identification of distinct phylogenetic signals. GUI and command-line versions of TreeScaper and a manual with tutorials can be downloaded from https://github.com/whuang08/TreeScaper/releases TreeScaper is distributed under the GNU General Public License. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Flowering Trees

Indian Academy of Sciences (India)

IAS Admin

Flowering Trees. Ailanthus excelsa Roxb. (INDIAN TREE OF. HEAVEN) of Simaroubaceae is a lofty tree with large pinnately compound alternate leaves, which are ... inflorescences, unisexual and greenish-yellow. Fruits are winged, wings many-nerved. Wood is used in making match sticks. 1. Male flower; 2. Female flower.

Why do trees die? Characterizing the drivers of background tree mortality

Science.gov (United States)

Das, Adrian J.; Stephenson, Nathan L.; Davis, Kristin P.

2016-01-01

The drivers of background tree mortality rates—the typical low rates of tree mortality found in forests in the absence of acute stresses like drought—are central to our understanding of forest dynamics, the effects of ongoing environmental changes on forests, and the causes and consequences of geographical gradients in the nature and strength of biotic interactions. To shed light on factors contributing to background tree mortality, we analyzed detailed pathological data from 200,668 tree-years of observation and 3,729 individual tree deaths, recorded over a 13-yr period in a network of old-growth forest plots in California's Sierra Nevada mountain range. We found that: (1) Biotic mortality factors (mostly insects and pathogens) dominated (58%), particularly in larger trees (86%). Bark beetles were the most prevalent (40%), even though there were no outbreaks during the study period; in contrast, the contribution of defoliators was negligible. (2) Relative occurrences of broad classes of mortality factors (biotic, 58%; suppression, 51%; and mechanical, 25%) are similar among tree taxa, but may vary with tree size and growth rate. (3) We found little evidence of distinct groups of mortality factors that predictably occur together on trees. Our results have at least three sets of implications. First, rather than being driven by abiotic factors such as lightning or windstorms, the “ambient” or “random” background mortality that many forest models presume to be independent of tree growth rate is instead dominated by biotic agents of tree mortality, with potentially critical implications for forecasting future mortality. Mechanistic models of background mortality, even for healthy, rapidly growing trees, must therefore include the insects and pathogens that kill trees. Second, the biotic agents of tree mortality, instead of occurring in a few predictable combinations, may generally act opportunistically and with a relatively large degree of independence from

Flowering Trees

Indian Academy of Sciences (India)

Flowering Trees. Gyrocarpus americanus Jacq. (Helicopter Tree) of Hernandiaceae is a moderate size deciduous tree that grows to about 12 m in height with a smooth, shining, greenish-white bark. The leaves are ovate, rarely irregularly ... flowers which are unpleasant smelling. Fruit is a woody nut with two long thin wings.

Cache-Oblivious Search Trees via Binary Trees of Small Height

DEFF Research Database (Denmark)

Brodal, G.S.; Fagerberg, R.; Jacob, R.

2002-01-01

We propose a version of cache oblivious search trees which is simpler than the previous proposal of Bender, Demaine and Farach-Colton and has the same complexity bounds. In particular, our data structure avoids the use of weight balanced B-trees, and can be implemented as just a single array......, and range queries in worst case O(logB n + k/B) memory transfers, where k is the size of the output.The basic idea of our data structure is to maintain a dynamic binary tree of height log n+O(1) using existing methods, embed this tree in a static binary tree, which in turn is embedded in an array in a cache...... oblivious fashion, using the van Emde Boas layout of Prokop.We also investigate the practicality of cache obliviousness in the area of search trees, by providing an empirical comparison of different methods for laying out a search tree in memory....

Flowering Trees

Indian Academy of Sciences (India)

Flowering Trees. Boswellia serrata Roxb. ex Colebr. (Indian Frankincense tree) of Burseraceae is a large-sized deciduous tree that is native to India. Bark is thin, greenish-ash-coloured that exfoliates into smooth papery flakes. Stem exudes pinkish resin ... Fruit is a three-valved capsule. A green gum-resin exudes from the ...

Systolic trees and systolic language recognition by tree automata

Energy Technology Data Exchange (ETDEWEB)

Steinby, M

1983-01-01

K. Culik II, J. Gruska, A. Salomaa and D. Wood have studied the language recognition capabilities of certain types of systolically operating networks of processors (see research reports Cs-81-32, Cs-81-36 and Cs-82-01, Univ. of Waterloo, Ontario, Canada). In this paper, their model for systolic VLSI trees is formalised in terms of standard tree automaton theory, and the way in which some known facts about recognisable forests and tree transductions can be applied in VLSI tree theory is demonstrated. 13 references.

DupTree: a program for large-scale phylogenetic analyses using gene tree parsimony.

Science.gov (United States)

Wehe, André; Bansal, Mukul S; Burleigh, J Gordon; Eulenstein, Oliver

2008-07-01

DupTree is a new software program for inferring rooted species trees from collections of gene trees using the gene tree parsimony approach. The program implements a novel algorithm that significantly improves upon the run time of standard search heuristics for gene tree parsimony, and enables the first truly genome-scale phylogenetic analyses. In addition, DupTree allows users to examine alternate rootings and to weight the reconciliation costs for gene trees. DupTree is an open source project written in C++. DupTree for Mac OS X, Windows, and Linux along with a sample dataset and an on-line manual are available at http://genome.cs.iastate.edu/CBL/DupTree

Anti-leishmanial evaluation of fraxinus xanthoxyloides (G. don) DC. collected from district Islamabad

International Nuclear Information System (INIS)

Younis, T.; Khan, M.R.; Zai, J.A.; Khan, H.; Shah, N.A.

2016-01-01

In this study, we have investigated phytochemical classes, antileishmanial and cytotoxic activity of Fraxinus xanthoxyloides (Oleaceae) leaves. Powder of F. xanthoxyloides leaves was extracted with methanol to obtain the crude extract (FXM) and the resultant was fractionated with solvents in escalating polarity; n-hexane (FXH), chloroform (FXC), ethyl acetate (FXE), n-butanol (FXB) and the residual aqueous (FXA) fraction. Quantitative estimation of terpenoids, coumarins, flavonoids, phenolics and tannins was conducted. Anti-leishmanial activity was performed against Leishmania tropica promastigote stage parasite while insecticidal activity was assessed through brine shrimps lethality assay. Our results showed the maximum concentration of terpenoids in FXC while the highest quantity of coumarins, flavonoids, phenolics and tannins was recorded in FXE. Presence of terpenoids was not detected in FXB and in FXA. Among the extract/fractions, FXC exhibited the highest anti-leishmanial activity with LD/sub 50/ of 15.239+-0.9 mu g/ml to that of glucantime (LD/sub 50/ = 5.6+-2.4 mu g/ml) a reference drug. FXH exhibited the anti-leishmanial activity of LD/sub 50/ = 40.68+-1.9 mu g/ml followed by FXE (LD/sub 50/ = 102.9+-3.1 mu g/ml). Similarly potent insecticidal activity was recorded (LD/sub 50/ = 28.15+-1.8 mu g/ml) for FXC followed by FXH (LD/sub 50/ = 67.59+-2.3 mu g/ml). However, other fractions exhibited low level of anti-leishmanial and insecticidal activity. Correlation analysis exhibited a strong association (p 0.05) with the insecticidal activity. The coumarins established a medium association with the insecticidal activity. Other chemical classes exhibited a moderate to low level of association with the anti-leishmanial and the insecticidal activity. On the basis of these results we can conclude that chloroform fraction of F. xanthoxyloides is a potential source for anti-leishmanial and insecticidal activities and further studies are required to isolate the active

Flowering Trees

Indian Academy of Sciences (India)

More Details Fulltext PDF. Volume 8 Issue 8 August 2003 pp 112-112 Flowering Trees. Zizyphus jujuba Lam. of Rhamnaceae · More Details Fulltext PDF. Volume 8 Issue 9 September 2003 pp 97-97 Flowering Trees. Moringa oleifera · More Details Fulltext PDF. Volume 8 Issue 10 October 2003 pp 100-100 Flowering Trees.

Embedding complete ternary tree in hypercubes using AVL trees

NARCIS (Netherlands)

S.A. Choudum; I. Raman (Indhumathi)

2008-01-01

htmlabstractA complete ternary tree is a tree in which every non-leaf vertex has exactly three children. We prove that a complete ternary tree of height h, TTh, is embeddable in a hypercube of dimension . This result coincides with the result of [2]. However, in this paper, the embedding utilizes

Ghost-tree: creating hybrid-gene phylogenetic trees for diversity analyses.

Science.gov (United States)

Fouquier, Jennifer; Rideout, Jai Ram; Bolyen, Evan; Chase, John; Shiffer, Arron; McDonald, Daniel; Knight, Rob; Caporaso, J Gregory; Kelley, Scott T

2016-02-24

Fungi play critical roles in many ecosystems, cause serious diseases in plants and animals, and pose significant threats to human health and structural integrity problems in built environments. While most fungal diversity remains unknown, the development of PCR primers for the internal transcribed spacer (ITS) combined with next-generation sequencing has substantially improved our ability to profile fungal microbial diversity. Although the high sequence variability in the ITS region facilitates more accurate species identification, it also makes multiple sequence alignment and phylogenetic analysis unreliable across evolutionarily distant fungi because the sequences are hard to align accurately. To address this issue, we created ghost-tree, a bioinformatics tool that integrates sequence data from two genetic markers into a single phylogenetic tree that can be used for diversity analyses. Our approach starts with a "foundation" phylogeny based on one genetic marker whose sequences can be aligned across organisms spanning divergent taxonomic groups (e.g., fungal families). Then, "extension" phylogenies are built for more closely related organisms (e.g., fungal species or strains) using a second more rapidly evolving genetic marker. These smaller phylogenies are then grafted onto the foundation tree by mapping taxonomic names such that each corresponding foundation-tree tip would branch into its new "extension tree" child. We applied ghost-tree to graft fungal extension phylogenies derived from ITS sequences onto a foundation phylogeny derived from fungal 18S sequences. Our analysis of simulated and real fungal ITS data sets found that phylogenetic distances between fungal communities computed using ghost-tree phylogenies explained significantly more variance than non-phylogenetic distances. The phylogenetic metrics also improved our ability to distinguish small differences (effect sizes) between microbial communities, though results were similar to non

Trees are good, but…

Science.gov (United States)

E.G. McPherson; F. Ferrini

2010-01-01

We know that “trees are good,” and most people believe this to be true. But if this is so, why are so many trees neglected, and so many tree wells empty? An individual’s attitude toward trees may result from their firsthand encounters with specific trees. Understanding how attitudes about trees are shaped, particularly aversion to trees, is critical to the business of...

Multiple-purpose trees for pastoral farming in New Zealand: with emphasis on tree legumes. [Lucerne Tree: Medick Tree

Energy Technology Data Exchange (ETDEWEB)

Davies, D J.G.; Macfarlane, R P

1979-01-01

The potential for soil conservation and agroforestry of several native and exotic legumes is discussed. Flowering period, chemical composition of leaves/pods, hardiness to frost and drought, timber value, forage potential for livestock and bees, ornamental value and other products are tabulated with information on up to 38 species. Two low-growing species that have proved useful for slope stabilization as well as forage are tree lucerne (Cytisus palmensis) and tree medick (Medicago arborea), the latter being shrubby and more suitable for cold districts. Gleditsia triacanthos is recommended as a shade and fodder tree for farm pasture.

Shedding light on tree growth : ring analysis of juvenile tropical trees

NARCIS (Netherlands)

Soliz Gamboa, C.C.

2010-01-01

In the understory of tropical forests light is believed to be the main limiting growth factor for the newly established trees. Trees growing in shade of the understory may experience periods of slow radial growth. It is expected that gaps created by tree or branch fall will provoke tree growth

Inferring species trees from incongruent multi-copy gene trees using the Robinson-Foulds distance

Science.gov (United States)

2013-01-01

Background Constructing species trees from multi-copy gene trees remains a challenging problem in phylogenetics. One difficulty is that the underlying genes can be incongruent due to evolutionary processes such as gene duplication and loss, deep coalescence, or lateral gene transfer. Gene tree estimation errors may further exacerbate the difficulties of species tree estimation. Results We present a new approach for inferring species trees from incongruent multi-copy gene trees that is based on a generalization of the Robinson-Foulds (RF) distance measure to multi-labeled trees (mul-trees). We prove that it is NP-hard to compute the RF distance between two mul-trees; however, it is easy to calculate this distance between a mul-tree and a singly-labeled species tree. Motivated by this, we formulate the RF problem for mul-trees (MulRF) as follows: Given a collection of multi-copy gene trees, find a singly-labeled species tree that minimizes the total RF distance from the input mul-trees. We develop and implement a fast SPR-based heuristic algorithm for the NP-hard MulRF problem. We compare the performance of the MulRF method (available at http://genome.cs.iastate.edu/CBL/MulRF/) with several gene tree parsimony approaches using gene tree simulations that incorporate gene tree error, gene duplications and losses, and/or lateral transfer. The MulRF method produces more accurate species trees than gene tree parsimony approaches. We also demonstrate that the MulRF method infers in minutes a credible plant species tree from a collection of nearly 2,000 gene trees. Conclusions Our new phylogenetic inference method, based on a generalized RF distance, makes it possible to quickly estimate species trees from large genomic data sets. Since the MulRF method, unlike gene tree parsimony, is based on a generic tree distance measure, it is appealing for analyses of genomic data sets, in which many processes such as deep coalescence, recombination, gene duplication and losses as

Inhibitory effects of coumarins from the stem barks of Fraxinus rhynchophylla on adipocyte differentiation in 3T3-L1 cells.

Science.gov (United States)

Shin, Eunjin; Choi, Kyeong-Mi; Yoo, Hwan-Soo; Lee, Chong-Kil; Hwang, Bang Yeon; Lee, Mi Kyeong

2010-01-01

In the course of screening anti-adipogenic activity of natural products employing the preadipocyte cell line, 3T3-L1 as an in vitro assay system, the EtOAc fraction of the stem barks of Fraxinus rhynchophylla DENCE (Oleaceae) showed significant inhibitory activity on adipocyte differentiation as assessed by measuring fat accumulation using Oil Red O staining. Activity-guided fractionation led to the isolation of six coumarins such as esculetin (1), scopoletin (2), fraxetin (3), fraxidin (4) esculin (5) and fraxin (6). Among the six coumarins isolated, esculetin (1) showed the most potent inhibitory activity on adipocyte differentiation, followed by fraxetin (3). Further studies with interval treatment demonstrated that esculetin (1) exerted inhibitory activity on adipocyte differentiation when treated within 2 d (days 0-2) after differentiation induction. We further investigated the effect of esculetin (1) on peroxisome proliferator activated receptor gamma (PPARgamma), one of the early adipogenic transcription factors. Esculetin (1) significantly blocked the induction of PPARgamma protein expression and inhibited adipocyte differentiation induced by troglitazone, a PPARgamma agonist. Taken together, these results suggest that esculetin (1), an active compound from F. rhynchophylla, inhibited early stage of adipogenic differentiation, in part, via inhibition of PPARgamma-dependent pathway.

Trees

Science.gov (United States)

Al-Khaja, Nawal

2007-01-01

This is a thematic lesson plan for young learners about palm trees and the importance of taking care of them. The two part lesson teaches listening, reading and speaking skills. The lesson includes parts of a tree; the modal auxiliary, can; dialogues and a role play activity.

Spectra of chemical trees

International Nuclear Information System (INIS)

Balasubramanian, K.

1982-01-01

A method is developed for obtaining the spectra of trees of NMR and chemical interests. The characteristic polynomials of branched trees can be obtained in terms of the characteristic polynomials of unbranched trees and branches by pruning the tree at the joints. The unbranched trees can also be broken down further until a tree containing just two vertices is obtained. The effectively reduces the order of the secular determinant of the tree used at the beginning to determinants of orders atmost equal to the number of vertices in the branch containing the largest number of vertices. An illustrative example of a NMR graph is given for which the 22 x 22 secular determinant is reduced to determinants of orders atmost 4 x 4 in just the second step of the algorithm. The tree pruning algorithm can be applied even to trees with no symmetry elements and such a factoring can be achieved. Methods developed here can be elegantly used to find if two trees are cospectral and to construct cospectral trees

The importance of considering rainfall partitioning in afforestation initiatives in semiarid climates: A comparison of common planted tree species in Tehran, Iran

International Nuclear Information System (INIS)

Sadeghi, Seyed Mohammad Moein; Attarod, Pedram; Van Stan, John Toland; Pypker, Thomas Grant

2016-01-01

As plantations become increasingly important sources of wood and fiber in arid/semiarid places, they have also become increasingly criticized for their hydrological impacts. An examination and comparison of gross rainfall (GR) partitioning across commonly-planted tree species (Pinus eldarica, Cupressus arizonica, Robinia pseudoacacia, and Fraxinus rotundifolia) in semiarid regions has great value for watershed and forest managers interested in managing canopy hydrological processes for societal benefit. Therefore, we performed a field study examining GR partitioning into throughfall (TF), stemflow (SF), and rainfall interception (I) for these species in the semiarid Chitgar Forest Park, Tehran, Iran. An advantage to our study is that we explore the effects of forest structural differences in plantation forests experiencing similar climatic factors and storm conditions. As such, variability in GR partitioning due to different meteorological conditions is minimized, allowing comparison of structural attributes across plantations. Our results show that commonly-selected afforestation species experiencing the same climate produced differing stand structures that differentially partition GR into TF, SF, and I. P. eldarica might be the best of the four species to plant if the primary goal of afforestation is to limit erosion and stormwater runoff as it intercepted more rainfall than other species. However, the high SF generation from F. rotundifolia, and low GR necessary to initiate SF, could maximize retention of water in the soils since SF has been shown to infiltrate along root pathways and access groundwater. A consideration of GR partitioning should be considered when selecting a species for afforestation/reforestation in water-limited ecosystems. - Highlights: • Measured rain partitioning of four most common species used in semiarid afforestation • Species rain partitioning differences are important in a water management. • Recommendations provided to guide

The importance of considering rainfall partitioning in afforestation initiatives in semiarid climates: A comparison of common planted tree species in Tehran, Iran

Energy Technology Data Exchange (ETDEWEB)

Sadeghi, Seyed Mohammad Moein, E-mail: moeinsadeghi@ut.ac.ir [Department of Forestry and Forest Economics, University of Tehran (Iran, Islamic Republic of); Attarod, Pedram [Department of Forestry and Forest Economics, University of Tehran (Iran, Islamic Republic of); Van Stan, John Toland [Department of Geology and Geography, Georgia Southern University, Statesboro, Georgia (United States); Pypker, Thomas Grant [Department of Natural Resource Sciences, Faculty of Science, Thompson Rivers University, Kamloops (Canada)

2016-10-15

As plantations become increasingly important sources of wood and fiber in arid/semiarid places, they have also become increasingly criticized for their hydrological impacts. An examination and comparison of gross rainfall (GR) partitioning across commonly-planted tree species (Pinus eldarica, Cupressus arizonica, Robinia pseudoacacia, and Fraxinus rotundifolia) in semiarid regions has great value for watershed and forest managers interested in managing canopy hydrological processes for societal benefit. Therefore, we performed a field study examining GR partitioning into throughfall (TF), stemflow (SF), and rainfall interception (I) for these species in the semiarid Chitgar Forest Park, Tehran, Iran. An advantage to our study is that we explore the effects of forest structural differences in plantation forests experiencing similar climatic factors and storm conditions. As such, variability in GR partitioning due to different meteorological conditions is minimized, allowing comparison of structural attributes across plantations. Our results show that commonly-selected afforestation species experiencing the same climate produced differing stand structures that differentially partition GR into TF, SF, and I. P. eldarica might be the best of the four species to plant if the primary goal of afforestation is to limit erosion and stormwater runoff as it intercepted more rainfall than other species. However, the high SF generation from F. rotundifolia, and low GR necessary to initiate SF, could maximize retention of water in the soils since SF has been shown to infiltrate along root pathways and access groundwater. A consideration of GR partitioning should be considered when selecting a species for afforestation/reforestation in water-limited ecosystems. - Highlights: • Measured rain partitioning of four most common species used in semiarid afforestation • Species rain partitioning differences are important in a water management. • Recommendations provided to guide

Dynamics of forest populations in the mountain resort region of the North Caucasus

Science.gov (United States)

Chalaya, Elena; Efimenko, Natalia; Slepykh, Olga; Slepykh, Viktor; Povolotskaya, Nina

2017-04-01

Prehistoric formula of forest species composition of the resort region Caucasian Mineralnye Vody (RR CMV) in the North Caucasus is 6Q3Cb1Fe [1]. According to it, undisturbed forests of the region consisted of the pedunculate oak (Quercus robur L.) and the durmast (Quercus cerris L.) by 60%, the European hornbeam (Carpinus betulus L.) by 30% and the European ash (Fraxinus excelsior L.) only by 10%. At present the formula of forest composition of the region is 5Fe3Cb2Q, according to it, the rate of oak-groves (the most valuable to resort landscape gardening) has reduced to 20%, and the ash-tree, though the rate of the hornbeam has not changed, increased up to 50%. Forest breeding populations in the RR CMV are referred to natural medical resources as they have high rehabilitation and climate-regulating properties, the change in forest breeding populations influences the conditions of the resort climate-landscape-therapy. The researches conducted in the perfect oak wood of vegetative origin in Beshtaugorsky Forestry Area (BFA) of the RR CMV have shown the reduction of the pedunculate oak in the tree-stand composition during 1984-2014 from 10 to 8 units in the composition: the European ash (1 unit) and the crataegus monogyna (Crataegus monogyna Jacq.), the checker tree (Sorbus torminalis (L.) Crantz), the common pear (Pyrus communis L.) have appeared [2]. The rate of the pedunculate oak decreased from 10 units to 9 in the perfect planting of the pedunculate oak of the artificial origin (Mashuk section of the forestry of BFA of the RR CMV) during 1986-2016. Among accompanying breeds there was the English field maple (Acer campestre L.), the Chinese elm in singular (Ulmus parvifolia Jacq.), the single-seed hawthorn. The reliable regrowth (4C3Fe3Ac+Q+Cm+Pc+Up) in number of 3,9 thousand pieces/hectare defines the perspective of complete replacement of the oak crop in the future on planting with dominance of the hornbeam and the involvement of the ash-tree and the English

MeshTree: A Delay optimised Overlay Multicast Tree Building Protocol

OpenAIRE

Tan, Su-Wei; Waters, A. Gill; Crawford, John

2005-01-01

We study decentralised low delay degree-constrained overlay multicast tree construction for single source real-time applications. This optimisation problem is NP-hard even if computed centrally. We identify two problems in traditional distributed solutions, namely the greedy problem and delay-cost trade-off. By offering solutions to these problems, we propose a new self-organising distributed tree building protocol called MeshTree. The main idea is to embed the delivery tree in a degree-bound...

Minimum variance rooting of phylogenetic trees and implications for species tree reconstruction.

Science.gov (United States)

Mai, Uyen; Sayyari, Erfan; Mirarab, Siavash

2017-01-01

Phylogenetic trees inferred using commonly-used models of sequence evolution are unrooted, but the root position matters both for interpretation and downstream applications. This issue has been long recognized; however, whether the potential for discordance between the species tree and gene trees impacts methods of rooting a phylogenetic tree has not been extensively studied. In this paper, we introduce a new method of rooting a tree based on its branch length distribution; our method, which minimizes the variance of root to tip distances, is inspired by the traditional midpoint rerooting and is justified when deviations from the strict molecular clock are random. Like midpoint rerooting, the method can be implemented in a linear time algorithm. In extensive simulations that consider discordance between gene trees and the species tree, we show that the new method is more accurate than midpoint rerooting, but its relative accuracy compared to using outgroups to root gene trees depends on the size of the dataset and levels of deviations from the strict clock. We show high levels of error for all methods of rooting estimated gene trees due to factors that include effects of gene tree discordance, deviations from the clock, and gene tree estimation error. Our simulations, however, did not reveal significant differences between two equivalent methods for species tree estimation that use rooted and unrooted input, namely, STAR and NJst. Nevertheless, our results point to limitations of existing scalable rooting methods.

Physiological responses of emerald ash borer larvae to feeding on different ash species reveal putative resistance mechanisms and insect counter-adaptations.

Science.gov (United States)

Rigsby, C M; Showalter, D N; Herms, D A; Koch, J L; Bonello, P; Cipollini, D

2015-07-01

Emerald ash borer, Agrilus planipennis Fairmaire, an Asian wood-boring beetle, has devastated ash (Fraxinus spp.) trees in North American forests and landscapes since its discovery there in 2002. In this study, we collected living larvae from EAB-resistant Manchurian ash (Fraxinus mandschurica), and susceptible white (Fraxinus americana) and green (Fraxinus pennsylvanica) ash hosts, and quantified the activity and production of selected detoxification, digestive, and antioxidant enzymes. We hypothesized that differences in larval physiology could be used to infer resistance mechanisms of ash. We found no differences in cytochrome P450, glutathione-S-transferase, carboxylesterase, sulfotransferase, and tryptic BApNAase activities between larvae feeding on different hosts. Despite this, Manchurian ash-fed larvae produced a single isozyme of low electrophoretic mobility that was not produced in white or green ash-fed larvae. Additionally, larvae feeding on white and green ash produced two serine protease isozymes of high electrophoretic mobility that were not observed in Manchurian ash-fed larvae. We also found lower activity of β-glucosidase and higher activities of monoamine oxidase, ortho-quinone reductase, catalase, superoxide dismutase, and glutathione reductase in Manchurian ash-fed larvae compared to larvae that had fed on susceptible ash. A single isozyme was detected for both catalase and superoxide dismutase in all larval groups. The activities of the quinone-protective and antioxidant enzymes are consistent with the resistance phenotype of the host species, with the highest activities measured in larvae feeding on resistant Manchurian ash. We conclude that larvae feeding on Manchurian ash could be under quinone and oxidative stress, suggesting these may be potential mechanisms of resistance of Manchurian ash to EAB larvae, and that quinone-protective and antioxidant enzymes are important counter-adaptations of larvae for dealing with these resistance

TreePlus: interactive exploration of networks with enhanced tree layouts.

Science.gov (United States)

Lee, Bongshin; Parr, Cynthia S; Plaisant, Catherine; Bederson, Benjamin B; Veksler, Vladislav D; Gray, Wayne D; Kotfila, Christopher

2006-01-01

Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food webs, ontologies, and social networks difficult to understand and interact with. We propose a new interactive Visual Analytics component called TreePlus that is based on a tree-style layout. TreePlus reveals the missing graph structure with visualization and interaction while maintaining good readability. To support exploration of the local structure of the graph and gathering of information from the extensive reading of labels, we use a guiding metaphor of "Plant a seed and watch it grow." It allows users to start with a node and expand the graph as needed, which complements the classic overview techniques that can be effective at (but often limited to) revealing clusters. We describe our design goals, describe the interface, and report on a controlled user study with 28 participants comparing TreePlus with a traditional graph interface for six tasks. In general, the advantage of TreePlus over the traditional interface increased as the density of the displayed data increased. Participants also reported higher levels of confidence in their answers with TreePlus and most of them preferred TreePlus.

Refining discordant gene trees.

Science.gov (United States)

Górecki, Pawel; Eulenstein, Oliver

2014-01-01

Evolutionary studies are complicated by discordance between gene trees and the species tree in which they evolved. Dealing with discordant trees often relies on comparison costs between gene and species trees, including the well-established Robinson-Foulds, gene duplication, and deep coalescence costs. While these costs have provided credible results for binary rooted gene trees, corresponding cost definitions for non-binary unrooted gene trees, which are frequently occurring in practice, are challenged by biological realism. We propose a natural extension of the well-established costs for comparing unrooted and non-binary gene trees with rooted binary species trees using a binary refinement model. For the duplication cost we describe an efficient algorithm that is based on a linear time reduction and also computes an optimal rooted binary refinement of the given gene tree. Finally, we show that similar reductions lead to solutions for computing the deep coalescence and the Robinson-Foulds costs. Our binary refinement of Robinson-Foulds, gene duplication, and deep coalescence costs for unrooted and non-binary gene trees together with the linear time reductions provided here for computing these costs significantly extends the range of trees that can be incorporated into approaches dealing with discordance.

Simple street tree sampling

Science.gov (United States)

David J. Nowak; Jeffrey T. Walton; James Baldwin; Jerry. Bond

2015-01-01

Information on street trees is critical for management of this important resource. Sampling of street tree populations provides an efficient means to obtain street tree population information. Long-term repeat measures of street tree samples supply additional information on street tree changes and can be used to report damages from catastrophic events. Analyses of...

TreeFam: a curated database of phylogenetic trees of animal gene families

DEFF Research Database (Denmark)

Li, Heng; Coghlan, Avril; Ruan, Jue

2006-01-01

TreeFam is a database of phylogenetic trees of gene families found in animals. It aims to develop a curated resource that presents the accurate evolutionary history of all animal gene families, as well as reliable ortholog and paralog assignments. Curated families are being added progressively......, based on seed alignments and trees in a similar fashion to Pfam. Release 1.1 of TreeFam contains curated trees for 690 families and automatically generated trees for another 11 646 families. These represent over 128 000 genes from nine fully sequenced animal genomes and over 45 000 other animal proteins...

Tree-space statistics and approximations for large-scale analysis of anatomical trees

DEFF Research Database (Denmark)

Feragen, Aasa; Owen, Megan; Petersen, Jens

2013-01-01

parametrize the relevant parts of tree-space well. Using the developed approximate statistics, we illustrate how the structure and geometry of airway trees vary across a population and show that airway trees with Chronic Obstructive Pulmonary Disease come from a different distribution in tree-space than...

Relating phylogenetic trees to transmission trees of infectious disease outbreaks.

Science.gov (United States)

Ypma, Rolf J F; van Ballegooijen, W Marijn; Wallinga, Jacco

2013-11-01

Transmission events are the fundamental building blocks of the dynamics of any infectious disease. Much about the epidemiology of a disease can be learned when these individual transmission events are known or can be estimated. Such estimations are difficult and generally feasible only when detailed epidemiological data are available. The genealogy estimated from genetic sequences of sampled pathogens is another rich source of information on transmission history. Optimal inference of transmission events calls for the combination of genetic data and epidemiological data into one joint analysis. A key difficulty is that the transmission tree, which describes the transmission events between infected hosts, differs from the phylogenetic tree, which describes the ancestral relationships between pathogens sampled from these hosts. The trees differ both in timing of the internal nodes and in topology. These differences become more pronounced when a higher fraction of infected hosts is sampled. We show how the phylogenetic tree of sampled pathogens is related to the transmission tree of an outbreak of an infectious disease, by the within-host dynamics of pathogens. We provide a statistical framework to infer key epidemiological and mutational parameters by simultaneously estimating the phylogenetic tree and the transmission tree. We test the approach using simulations and illustrate its use on an outbreak of foot-and-mouth disease. The approach unifies existing methods in the emerging field of phylodynamics with transmission tree reconstruction methods that are used in infectious disease epidemiology.

Decision-Tree Program

Science.gov (United States)

Buntine, Wray

1994-01-01

IND computer program introduces Bayesian and Markov/maximum-likelihood (MML) methods and more-sophisticated methods of searching in growing trees. Produces more-accurate class-probability estimates important in applications like diagnosis. Provides range of features and styles with convenience for casual user, fine-tuning for advanced user or for those interested in research. Consists of four basic kinds of routines: data-manipulation, tree-generation, tree-testing, and tree-display. Written in C language.

Tree-growth analyses to estimate tree species' drought tolerance.

Science.gov (United States)

Eilmann, Britta; Rigling, Andreas

2012-02-01

Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree species' potential for surviving future aggravated environmental conditions is rather demanding. The aim of this study was to find a tree-ring-based method suitable for identifying very drought-tolerant species, particularly potential substitute species for Scots pine (Pinus sylvestris L.) in Valais. In this inner-Alpine valley, Scots pine used to be the dominating species for dry forests, but today it suffers from high drought-induced mortality. We investigate the growth response of two native tree species, Scots pine and European larch (Larix decidua Mill.), and two non-native species, black pine (Pinus nigra Arnold) and Douglas fir (Pseudotsuga menziesii Mirb. var. menziesii), to drought. This involved analysing how the radial increment of these species responded to increasing water shortage (abandonment of irrigation) and to increasingly frequent drought years. Black pine and Douglas fir are able to cope with drought better than Scots pine and larch, as they show relatively high radial growth even after irrigation has been stopped and a plastic growth response to drought years. European larch does not seem to be able to cope with these dry conditions as it lacks the ability to recover from drought years. The analysis of trees' short-term response to extreme climate events seems to be the most promising and suitable method for detecting how tolerant a tree species is towards drought. However, combining all the methods used in this study provides a complete picture of how water shortage could limit species.

Are trees long-lived?

Science.gov (United States)

Kevin T. Smith

2009-01-01

Trees and tree care can capture the best of people's motivations and intentions. Trees are living memorials that help communities heal at sites of national tragedy, such as Oklahoma City and the World Trade Center. We mark the places of important historical events by the trees that grew nearby even if the original tree, such as the Charter Oak in Connecticut or...

There's Life in Hazard Trees

Science.gov (United States)

Mary Torsello; Toni McLellan

The goals of hazard tree management programs are to maximize public safety and maintain a healthy sustainable tree resource. Although hazard tree management frequently targets removal of trees or parts of trees that attract wildlife, it can take into account a diversity of tree values. With just a little extra planning, hazard tree management can be highly beneficial...

Translations on Narcotics and Dangerous Drugs No. 301.

Science.gov (United States)

1977-05-23

One Escaped Escaped Crewman Treated for Burns, Leaves Country Briefs Marihuana Plantation Found in Cundinamarca 34 Marihuana ’Factory’ Raid 34...Azcapotzalco Battalion (Jorge Reyes E; EXCELSIOR, 13 Apr 77) 37 Traffickers, Aircraft, Marihuana Seized (Rafael Medina Cruz; EXCELSIOR, 12 Apr 77) 38...Former Federal Agent Denies Charges (EL DIARIO, 7 Apr 77) 39 Federal Agents Burn Marihuana Cache (EL DIARIO, 6 Apr 77) 41 Penitentiary

Fast Tree: Computing Large Minimum-Evolution Trees with Profiles instead of a Distance Matrix

Energy Technology Data Exchange (ETDEWEB)

N. Price, Morgan; S. Dehal, Paramvir; P. Arkin, Adam

2009-07-31

Gene families are growing rapidly, but standard methods for inferring phylogenies do not scale to alignments with over 10,000 sequences. We present FastTree, a method for constructing large phylogenies and for estimating their reliability. Instead of storing a distance matrix, FastTree stores sequence profiles of internal nodes in the tree. FastTree uses these profiles to implement neighbor-joining and uses heuristics to quickly identify candidate joins. FastTree then uses nearest-neighbor interchanges to reduce the length of the tree. For an alignment with N sequences, L sites, and a different characters, a distance matrix requires O(N^2) space and O(N^2 L) time, but FastTree requires just O( NLa + N sqrt(N) ) memory and O( N sqrt(N) log(N) L a ) time. To estimate the tree's reliability, FastTree uses local bootstrapping, which gives another 100-fold speedup over a distance matrix. For example, FastTree computed a tree and support values for 158,022 distinct 16S ribosomal RNAs in 17 hours and 2.4 gigabytes of memory. Just computing pairwise Jukes-Cantor distances and storing them, without inferring a tree or bootstrapping, would require 17 hours and 50 gigabytes of memory. In simulations, FastTree was slightly more accurate than neighbor joining, BIONJ, or FastME; on genuine alignments, FastTree's topologies had higher likelihoods. FastTree is available at http://microbesonline.org/fasttree.

TreeRipper web application: towards a fully automated optical tree recognition software

Directory of Open Access Journals (Sweden)

Hughes Joseph

2011-05-01

Full Text Available Abstract Background Relationships between species, genes and genomes have been printed as trees for over a century. Whilst this may have been the best format for exchanging and sharing phylogenetic hypotheses during the 20th century, the worldwide web now provides faster and automated ways of transferring and sharing phylogenetic knowledge. However, novel software is needed to defrost these published phylogenies for the 21st century. Results TreeRipper is a simple website for the fully-automated recognition of multifurcating phylogenetic trees (http://linnaeus.zoology.gla.ac.uk/~jhughes/treeripper/. The program accepts a range of input image formats (PNG, JPG/JPEG or GIF. The underlying command line c++ program follows a number of cleaning steps to detect lines, remove node labels, patch-up broken lines and corners and detect line edges. The edge contour is then determined to detect the branch length, tip label positions and the topology of the tree. Optical Character Recognition (OCR is used to convert the tip labels into text with the freely available tesseract-ocr software. 32% of images meeting the prerequisites for TreeRipper were successfully recognised, the largest tree had 115 leaves. Conclusions Despite the diversity of ways phylogenies have been illustrated making the design of a fully automated tree recognition software difficult, TreeRipper is a step towards automating the digitization of past phylogenies. We also provide a dataset of 100 tree images and associated tree files for training and/or benchmarking future software. TreeRipper is an open source project licensed under the GNU General Public Licence v3.

MixtureTree annotator: a program for automatic colorization and visual annotation of MixtureTree.

Directory of Open Access Journals (Sweden)

Shu-Chuan Chen

Full Text Available The MixtureTree Annotator, written in JAVA, allows the user to automatically color any phylogenetic tree in Newick format generated from any phylogeny reconstruction program and output the Nexus file. By providing the ability to automatically color the tree by sequence name, the MixtureTree Annotator provides a unique advantage over any other programs which perform a similar function. In addition, the MixtureTree Annotator is the only package that can efficiently annotate the output produced by MixtureTree with mutation information and coalescent time information. In order to visualize the resulting output file, a modified version of FigTree is used. Certain popular methods, which lack good built-in visualization tools, for example, MEGA, Mesquite, PHY-FI, TreeView, treeGraph and Geneious, may give results with human errors due to either manually adding colors to each node or with other limitations, for example only using color based on a number, such as branch length, or by taxonomy. In addition to allowing the user to automatically color any given Newick tree by sequence name, the MixtureTree Annotator is the only method that allows the user to automatically annotate the resulting tree created by the MixtureTree program. The MixtureTree Annotator is fast and easy-to-use, while still allowing the user full control over the coloring and annotating process.

On Determining if Tree-based Networks Contain Fixed Trees.

Science.gov (United States)

Anaya, Maria; Anipchenko-Ulaj, Olga; Ashfaq, Aisha; Chiu, Joyce; Kaiser, Mahedi; Ohsawa, Max Shoji; Owen, Megan; Pavlechko, Ella; St John, Katherine; Suleria, Shivam; Thompson, Keith; Yap, Corrine

2016-05-01

We address an open question of Francis and Steel about phylogenetic networks and trees. They give a polynomial time algorithm to decide if a phylogenetic network, N, is tree-based and pose the problem: given a fixed tree T and network N, is N based on T? We show that it is [Formula: see text]-hard to decide, by reduction from 3-Dimensional Matching (3DM) and further that the problem is fixed-parameter tractable.

Whole-tree distribution and temporal variation of non-structural carbohydrates in broadleaf evergreen trees.

Science.gov (United States)

Smith, Merryn G; Miller, Rebecca E; Arndt, Stefan K; Kasel, Sabine; Bennett, Lauren T

2018-04-01

Non-structural carbohydrates (NSCs) form a fundamental yet poorly quantified carbon pool in trees. Studies of NSC seasonality in forest trees have seldom measured whole-tree NSC stocks and allocation among organs, and are not representative of all tree functional types. Non-structural carbohydrate research has primarily focussed on broadleaf deciduous and coniferous evergreen trees with distinct growing seasons, while broadleaf evergreen trees remain under-studied despite their different growth phenology. We measured whole-tree NSC allocation and temporal variation in Eucalyptus obliqua L'Hér., a broadleaf evergreen tree species typically occurring in mixed-age temperate forests, which has year-round growth and the capacity to resprout after fire. Our overarching objective was to improve the empirical basis for understanding the functional importance of NSC allocation and stock changes at the tree- and organ-level in this tree functional type. Starch was the principal storage carbohydrate and was primarily stored in the stem and roots of young (14-year-old) trees rather than the lignotuber, which did not appear to be a specialized starch storage organ. Whole-tree NSC stocks were depleted during spring and summer due to significant decreases in starch mass in the roots and stem, seemingly to support root and crown growth but potentially exacerbated by water stress in summer. Seasonality of stem NSCs differed between young and mature trees, and was not synchronized with stem basal area increments in mature trees. Our results suggest that the relative magnitude of seasonal NSC stock changes could vary with tree growth stage, and that the main drivers of NSC fluctuations in broadleaf evergreen trees in temperate biomes could be periodic disturbances such as summer drought and fire, rather than growth phenology. These results have implications for understanding post-fire tree recovery via resprouting, and for incorporating NSC pools into carbon models of mixed

The effect of contaminated groundwater on tree growth: A tree-ring analysis

International Nuclear Information System (INIS)

LeBlanc, D.C.; Loehle, C.

1990-10-01

A study was conducted on the effect of contaminated groundwater seepage on tree growth downslope from F- and H-Area seepage basins of the Savannah River Site. Trees in wetlands along Four Mile Creek began to show localized stress and mortality in the late 1970s. Extreme winter temperatures and high rainfall were ruled out as potential causal factors of tree stress. Drought was shown to affect trees in both contaminated and uncontaminated zones, but trees in uncontaminated areas exhibit better recovery after drought than trees in contaminated areas. Pollution-mediated alteration of soil acidity and aluminum, sodium, and heavy metal concentrations likely acted to predispose trees to decline, with severe drought acting as the trigger for decline initiation and tree death. Thus, a moderate pollution loading, not sufficient to cause visible damage of itself, may create conditions in which sudden, severe decline could result from natural stresses. This mechanism of forest decline is common, and should be considered in evaluations of the impact of pollution on wetland forest systems. 28 refs., 4 figs., 6 tabs

SILVA tree viewer: interactive web browsing of the SILVA phylogenetic guide trees.

Science.gov (United States)

Beccati, Alan; Gerken, Jan; Quast, Christian; Yilmaz, Pelin; Glöckner, Frank Oliver

2017-09-30

Phylogenetic trees are an important tool to study the evolutionary relationships among organisms. The huge amount of available taxa poses difficulties in their interactive visualization. This hampers the interaction with the users to provide feedback for the further improvement of the taxonomic framework. The SILVA Tree Viewer is a web application designed for visualizing large phylogenetic trees without requiring the download of any software tool or data files. The SILVA Tree Viewer is based on Web Geographic Information Systems (Web-GIS) technology with a PostgreSQL backend. It enables zoom and pan functionalities similar to Google Maps. The SILVA Tree Viewer enables access to two phylogenetic (guide) trees provided by the SILVA database: the SSU Ref NR99 inferred from high-quality, full-length small subunit sequences, clustered at 99% sequence identity and the LSU Ref inferred from high-quality, full-length large subunit sequences. The Tree Viewer provides tree navigation, search and browse tools as well as an interactive feedback system to collect any kinds of requests ranging from taxonomy to data curation and improving the tool itself.

D2-tree

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Sioutas, Spyros; Pantazos, Kostas

2015-01-01

We present a new overlay, called the Deterministic Decentralized tree (D2-tree). The D2-tree compares favorably to other overlays for the following reasons: (a) it provides matching and better complexities, which are deterministic for the supported operations; (b) the management of nodes (peers...

Tree felling 2014

CERN Multimedia

2014-01-01

With a view to creating new landscapes and making its population of trees safer and healthier, this winter CERN will complete the tree-felling campaign started in 2010.   Tree felling will take place between 15 and 22 November on the Swiss part of the Meyrin site. This work is being carried out above all for safety reasons. The trees to be cut down are at risk of falling as they are too old and too tall to withstand the wind. In addition, the roots of poplar trees are very powerful and spread widely, potentially damaging underground networks, pavements and roadways. Compensatory tree planting campaigns will take place in the future, subject to the availability of funding, with the aim of creating coherent landscapes while also respecting the functional constraints of the site. These matters are being considered in close collaboration with the Geneva nature and countryside directorate (Direction générale de la nature et du paysage, DGNP). GS-SE Group

Phylogenetic trees

OpenAIRE

Baños, Hector; Bushek, Nathaniel; Davidson, Ruth; Gross, Elizabeth; Harris, Pamela E.; Krone, Robert; Long, Colby; Stewart, Allen; Walker, Robert

2016-01-01

We introduce the package PhylogeneticTrees for Macaulay2 which allows users to compute phylogenetic invariants for group-based tree models. We provide some background information on phylogenetic algebraic geometry and show how the package PhylogeneticTrees can be used to calculate a generating set for a phylogenetic ideal as well as a lower bound for its dimension. Finally, we show how methods within the package can be used to compute a generating set for the join of any two ideals.

Identifying the rooted species tree from the distribution of unrooted gene trees under the coalescent.

Science.gov (United States)

Allman, Elizabeth S; Degnan, James H; Rhodes, John A

2011-06-01

Gene trees are evolutionary trees representing the ancestry of genes sampled from multiple populations. Species trees represent populations of individuals-each with many genes-splitting into new populations or species. The coalescent process, which models ancestry of gene copies within populations, is often used to model the probability distribution of gene trees given a fixed species tree. This multispecies coalescent model provides a framework for phylogeneticists to infer species trees from gene trees using maximum likelihood or Bayesian approaches. Because the coalescent models a branching process over time, all trees are typically assumed to be rooted in this setting. Often, however, gene trees inferred by traditional phylogenetic methods are unrooted. We investigate probabilities of unrooted gene trees under the multispecies coalescent model. We show that when there are four species with one gene sampled per species, the distribution of unrooted gene tree topologies identifies the unrooted species tree topology and some, but not all, information in the species tree edges (branch lengths). The location of the root on the species tree is not identifiable in this situation. However, for 5 or more species with one gene sampled per species, we show that the distribution of unrooted gene tree topologies identifies the rooted species tree topology and all its internal branch lengths. The length of any pendant branch leading to a leaf of the species tree is also identifiable for any species from which more than one gene is sampled.

Covering tree with stars

DEFF Research Database (Denmark)

Baumbach, Jan; Guo, Jiong; Ibragimov, Rashid

2015-01-01

We study the tree edit distance problem with edge deletions and edge insertions as edit operations. We reformulate a special case of this problem as Covering Tree with Stars (CTS): given a tree T and a set of stars, can we connect the stars in by adding edges between them such that the resulting...... tree is isomorphic to T? We prove that in the general setting, CST is NP-complete, which implies that the tree edit distance considered here is also NP-hard, even when both input trees having diameters bounded by 10. We also show that, when the number of distinct stars is bounded by a constant k, CTS...

Trees in the city: valuing street trees in Portland, Oregon

Science.gov (United States)

G.H. Donovan; D.T. Butry

2010-01-01

We use a hedonic price model to simultaneously estimate the effects of street trees on the sales price and the time-on-market (TOM) of houses in Portland. Oregon. On average, street trees add $8,870 to sales price and reduce TOM by 1.7 days. In addition, we found that the benefits of street trees spill over to neighboring houses. Because the provision and maintenance...

Urban tree growth modeling

Science.gov (United States)

E. Gregory McPherson; Paula J. Peper

2012-01-01

This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...

Electron Tree

DEFF Research Database (Denmark)

Appelt, Ane L; Rønde, Heidi S

2013-01-01

The photo shows a close-up of a Lichtenberg figure – popularly called an “electron tree” – produced in a cylinder of polymethyl methacrylate (PMMA). Electron trees are created by irradiating a suitable insulating material, in this case PMMA, with an intense high energy electron beam. Upon discharge......, during dielectric breakdown in the material, the electrons generate branching chains of fractures on leaving the PMMA, producing the tree pattern seen. To be able to create electron trees with a clinical linear accelerator, one needs to access the primary electron beam used for photon treatments. We...... appropriated a linac that was being decommissioned in our department and dismantled the head to circumvent the target and ion chambers. This is one of 24 electron trees produced before we had to stop the fun and allow the rest of the accelerator to be disassembled....

Classification and regression trees

CERN Document Server

Breiman, Leo; Olshen, Richard A; Stone, Charles J

1984-01-01

The methodology used to construct tree structured rules is the focus of this monograph. Unlike many other statistical procedures, which moved from pencil and paper to calculators, this text's use of trees was unthinkable before computers. Both the practical and theoretical sides have been developed in the authors' study of tree methods. Classification and Regression Trees reflects these two sides, covering the use of trees as a data analysis method, and in a more mathematical framework, proving some of their fundamental properties.

FB-Tree: A B+-Tree for Flash-Based SSDs

DEFF Research Database (Denmark)

Jørgensen, Martin V.; Rasmussen, René B.; Saltenis, Simonas

2011-01-01

Due to their many advantages, flash-based SSDs (Solid-State Drives) have become a mainstream alternative to magnetic disks for database servers. Nevertheless, database systems, designed and optimized for magnetic disks, still do not fully exploit all the benefits of the new technology. We propose....... As a consequence, the FB-tree outperforms a regular B+-tree in all scenarios tested. For instance, the throughput of a random workload of 75% updates increases by a factor of three using only two times the space of the B+-tree....

Benefit-based tree valuation

Science.gov (United States)

E.G. McPherson

2007-01-01

Benefit-based tree valuation provides alternative estimates of the fair and reasonable value of trees while illustrating the relative contribution of different benefit types. This study compared estimates of tree value obtained using cost- and benefit-based approaches. The cost-based approach used the Council of Landscape and Tree Appraisers trunk formula method, and...

Towards Biological Restoration of Tehran Megalopolis River Valleys- Case Study: Farahzad River

Science.gov (United States)

Samadi, Nafishe; Oveis Torabi, Seyed; Akhani, Hossein

2017-04-01

Towards biological restoration of Tehran megalopolis river-valleys: case study Farahzad river 1Nafiseh Samadi, 2OveisTorabi, 3Hossein Akhani 1Mahsab Shargh Company, Tehran ,Iran, nafiseh19@gmail.com 2 Mahsab Shargh Company, Tehran ,Iran, weg@tna-co.com 3Department of Plant Sciences, Halophytes and C4 Research Laboratory, School of Biology, College of Sciences, University of Tehran, PO Box 14155-6455, Tehran, Iran, akhani@khayam.ut.ac.ir Tehran is located in northcentral parts of Iran on the alluvium of southern Alborz Mountains. Seven rivers originated from the highlands of N Tehran run inside and around the city. Many of these river valleys have been deformed by a variety of urban utilizations such as garden, building, canal, park, autobahn etc. Tehran with more than eight million populations suffered from adverse environmental conditions such as pollution and scarcity of natural habitats for recreational activities. Ecological restoration of altered river valleys of Tehran is one of the priorities of Tehran municipality started as a pilot project in Farahzad river. Intensive disturbance, conversion into various urban utilization, illegal building construction, waste water release into the river, garbage accumulation, artificial park constructions and domination of invasive species have largely altered the river. Parts of the river located in Pardisan Nature Park was studied before its complete deformation into a modern park. The riparian vegetation consisted of Tamarix ramosissima and Salix acmophylla shrubs with large number of aquatic and palustric plants. The norther parts of the river still contain semi-natural vegetation which change into patchy and intensive degraded habitats towards its southern parts. In northern parts of valley there are old gardens of Morus alba and Juglans regia, and planted trees such as Plataneus oreientalis and Acer negundo. Salix acmophylla, Fraxinus excelsior and Celtis caucasica are native species growing on river margin or

Fragmentation of random trees

International Nuclear Information System (INIS)

Kalay, Z; Ben-Naim, E

2015-01-01

We study fragmentation of a random recursive tree into a forest by repeated removal of nodes. The initial tree consists of N nodes and it is generated by sequential addition of nodes with each new node attaching to a randomly-selected existing node. As nodes are removed from the tree, one at a time, the tree dissolves into an ensemble of separate trees, namely, a forest. We study statistical properties of trees and nodes in this heterogeneous forest, and find that the fraction of remaining nodes m characterizes the system in the limit N→∞. We obtain analytically the size density ϕ s of trees of size s. The size density has power-law tail ϕ s ∼s −α with exponent α=1+(1/m). Therefore, the tail becomes steeper as further nodes are removed, and the fragmentation process is unusual in that exponent α increases continuously with time. We also extend our analysis to the case where nodes are added as well as removed, and obtain the asymptotic size density for growing trees. (paper)

FTAP, Minimal Cut Sets of Arbitrary Fault Trees. FRTPLT, Fault Tree Structure and Logical Gates Plot for Program FTAP. FRTGEN, Fault Trees by Sub-tree Generator from Parent Tree for Program FTAP

International Nuclear Information System (INIS)

Willie, Randall R.; Rabien, U.

1997-01-01

1 - Description of problem or function: FTAP is a general-purpose program for deriving minimal reliability cut and path set families from the fault tree for a complex system. The program has a number of useful features that make it well-suited to nearly all fault tree applications. An input fault tree may specify the system state as any logical function of subsystem or component state variables or complements of these variables; thus, for instance, 'exclusive-or' type relations may be formed. When fault tree logical relations involve complements of state variables, the analyst may instruct FTAP to produce a family of prime implicants, a generalization of the minimal cut set concept. The program offers the flexibility of several distinct methods of generating cut set families. FTAP can also identify certain subsystems as system modules and provide a collection of minimal cut set families that essentially expresses the system state as a function of these module state variables. Another feature allows a useful subfamily to be obtained when the family of minimal cut sets or prime implicants is too large to be found in its entirety; this subfamily may consist of only those sets not containing more than some fixed number of elements or only those sets 'interesting' to the analyst in some special sense. Finally, the analyst can modify the input fault tree in various ways by declaring state variables identically true or false. 2 - Method of solution: Fault tree methods are based on the observation that the system state, either working or failed, can usually be expressed as a Boolean relation between states of several large, readily identifiable subsystems. The state of each subsystem in turn depends on states of simpler subsystems and components which compose it, so that the state of the system itself is determined by a hierarchy of logical relationships between states of subsystems. A fault tree is a graphical representation of these relationships. 3 - Restrictions on the

Winter Birch Trees

Science.gov (United States)

Sweeney, Debra; Rounds, Judy

2011-01-01

Trees are great inspiration for artists. Many art teachers find themselves inspired and maybe somewhat obsessed with the natural beauty and elegance of the lofty tree, and how it changes through the seasons. One such tree that grows in several regions and always looks magnificent, regardless of the time of year, is the birch. In this article, the…

36 CFR 223.4 - Exchange of trees or portions of trees.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Exchange of trees or portions of trees. 223.4 Section 223.4 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER General Provisions § 223.4 Exchange of trees or...

How many trees are enough? Tree death and the urban canopy

Science.gov (United States)

Lara A. Roman

2014-01-01

Massive city tree planting campaigns have invigorated the urban forestry movement, and engaged politicians, planners, and the public in urban greening. Million tree initiatives have been launched in Los Angeles, CA; Denver, CO; New York City, NY; Philadelphia, PA, and other cities. Sacramento, CA even has a five million tree program. These...

Keeping trees as assets

Science.gov (United States)

Kevin T. Smith

2009-01-01

Landscape trees have real value and contribute to making livable communities. Making the most of that value requires providing trees with the proper care and attention. As potentially large and long-lived organisms, trees benefit from commitment to regular care that respects the natural tree system. This system captures, transforms, and uses energy to survive, grow,...

Visualization of Uncertain Contour Trees

DEFF Research Database (Denmark)

Kraus, Martin

2010-01-01

Contour trees can represent the topology of large volume data sets in a relatively compact, discrete data structure. However, the resulting trees often contain many thousands of nodes; thus, many graph drawing techniques fail to produce satisfactory results. Therefore, several visualization methods...... were proposed recently for the visualization of contour trees. Unfortunately, none of these techniques is able to handle uncertain contour trees although any uncertainty of the volume data inevitably results in partially uncertain contour trees. In this work, we visualize uncertain contour trees...... by combining the contour trees of two morphologically filtered versions of a volume data set, which represent the range of uncertainty. These two contour trees are combined and visualized within a single image such that a range of potential contour trees is represented by the resulting visualization. Thus...

Impact of solid waste burning air pollution on some physio-anatomical characteristics of some plants

International Nuclear Information System (INIS)

Laghari, S.K.; Zaidi, M.A.

2015-01-01

Present study evaluated the effect of solid waste burning pollution on carbohydrate, stomata and chlorophyll contents of seven different plant species. Leaf samples of Artemisia maritima L., Fraxinus excelsior L., Amaranthus viridis L., Cynodon dactylon L., Chenopodium album L., Robinia pseudoacacia L., and Sophora mollis (Royle) Baker, growing in the (1m, 500m and 1000m distance) vicinity of burning points at residential colony, University of Baluchistan Quetta were collected. Results revealed that the carbohydrate, chlorophyll a and b and total chlorophyll contents in the leaves of selected plant species were found to be significantly low at 1m distance, but as the distance from the source of pollution increased (500m and 1000m) these contents increased accordingly. Generally the percentage of completely and partially clogged stomata was found higher near the pollution source (1m distance). The percentage of open stomata in all investigated plant species was noticed lower near the pollution source (1m distance), while with the increase of distance (500m-1000m) the percentage of open stomata increased accordingly. As regard to carbohydrate and chlorophyll contents, the Artemisia maritima L., were found most sensitive to air pollution in all four directions at 1m distances as compared to the other species. While plant species, Cynodon dactylon L. showed more resistant to air pollution effect as regard to carbohydrate contents and high percentage of open stomata at 1m distances with respect to other species. (author)

Forest FIRE and FIRE wood : tools for tree automata and tree algorithms

NARCIS (Netherlands)

Cleophas, L.G.W.A.; Piskorski, J.; Watson, B.W.; Yli-Jyrä, A.

2009-01-01

Pattern matching, acceptance, and parsing algorithms on node-labeled, ordered, ranked trees ('tree algorithms') are important for applications such as instruction selection and tree transformation/term rewriting. Many such algorithms have been developed. They often are based on results from such

Monitoring Million Trees LA: Tree performance during the early years and future benefits

Science.gov (United States)

E. Gregory McPherson

2014-01-01

Million Trees LA (MTLA) is one of several large-scale mayoral tree planting initiatives striving to create more livable cities through urban forestry. This study combined field sampling of tree survival and growth with numerical modeling of future benefits to assess performance of MTLA plantings. From 2006 to 2010 MTLA planted a diverse mix of 91,786 trees....

Skewed Binary Search Trees

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Moruz, Gabriel

2006-01-01

It is well-known that to minimize the number of comparisons a binary search tree should be perfectly balanced. Previous work has shown that a dominating factor over the running time for a search is the number of cache faults performed, and that an appropriate memory layout of a binary search tree...... can reduce the number of cache faults by several hundred percent. Motivated by the fact that during a search branching to the left or right at a node does not necessarily have the same cost, e.g. because of branch prediction schemes, we in this paper study the class of skewed binary search trees....... For all nodes in a skewed binary search tree the ratio between the size of the left subtree and the size of the tree is a fixed constant (a ratio of 1/2 gives perfect balanced trees). In this paper we present an experimental study of various memory layouts of static skewed binary search trees, where each...

The ghosts of trees past: savanna trees create enduring legacies in plant species composition.

Science.gov (United States)

Stahlheber, Karen A; Crispin, Kimberly L; Anton, Cassidy; D'Antonio, Carla M

2015-09-01

Isolated trees in savannas worldwide are known to modify their local environment and interact directly with neighboring plants. Less is known about how related tree species differ in their impacts on surrounding communities, how the effects of trees vary between years, and how composition might change following loss of the tree. To address these knowledge gaps, we explored the following questions: How do savanna trees influence the surrounding composition of herbaceous plants? Is the influence of trees consistent across different species and years? How does this change following the death of the tree? We surveyed herbaceous species composition and environmental attributes surrounding living and dead evergreen and deciduous Quercus trees in California (USA) savannas across several years that differed in their total precipitation. Oak trees of all species created distinct, homogenous understory communities dominated by exotic grasses across several sites. The composition of the low-diversity understory communities showed less interannual variation than open grassland, despite a two-fold difference in precipitation between the driest and wettest year. Vegetation composition was correlated with variation in soil properties, which were strongly affected by trees. Oaks also influenced the communities beyond the edge of the crown, but this depended on site and oak species. Low-diversity understory communities persisted up to 43 years following the death of the tree. A gradual decline in the effect of trees on the physical, environment following death did not result in vegetation becoming more similar to open grassland over time. The presence of long-lasting legacies of past tree crowns highlights the difficulty of assigning control of the current distribution of herbaceous species in grassland to their contemporary environment.

Barking up the wrong tree: injuries due to falls from trees in Solomon Islands.

Science.gov (United States)

Negin, Joel; Vizintin, Pavle; Houasia, Patrick; Martiniuk, Alexandra L C

2014-12-11

To investigate tree-related injuries in Solomon Islands by the types of trees involved, who is affected and the types of injuries caused. Descriptive case series of all cases of injuries related to trees presenting to the National Referral Hospital in Honiara from 1994 to 2011. Data were collected by the attending clinician using a Trauma Epidemiology form, which provides information on age, sex, cause of injury and type of fracture. Number of injuries by tree type, sex and age. Of the 7651 injuries in the database, 1107 (14%) were caused by falls from trees. Falls from coconut trees led to the highest number of injuries, followed by falls from mango, guava, apple and nut trees. Overall, 85% of injuries occurred in individuals aged trees, 77% of patients were aged tree types. Overall, 71% of injuries occurred among males. Of all injuries, 92% were fractures, 3% were dislocations and 5% were non-fracture, non-dislocation injuries. The arm (including wrist, elbow and hand) was the most common location of injury across all tree types. Distal radius fractures in the forearm were particularly common, as were ulna fractures. While mangos and guavas are undeniably delicious, the quest for their flesh can be hazardous. Children will always climb trees, but the search for food among children in lower-income settings may lead to higher rates of injury.

Recursive Trees for Practical ORAM

Directory of Open Access Journals (Sweden)

Moataz Tarik

2015-06-01

Full Text Available We present a new, general data structure that reduces the communication cost of recent tree-based ORAMs. Contrary to ORAM trees with constant height and path lengths, our new construction r-ORAM allows for trees with varying shorter path length. Accessing an element in the ORAM tree results in different communication costs depending on the location of the element. The main idea behind r-ORAM is a recursive ORAM tree structure, where nodes in the tree are roots of other trees. While this approach results in a worst-case access cost (tree height at most as any recent tree-based ORAM, we show that the average cost saving is around 35% for recent binary tree ORAMs. Besides reducing communication cost, r-ORAM also reduces storage overhead on the server by 4% to 20% depending on the ORAM’s client memory type. To prove r-ORAM’s soundness, we conduct a detailed overflow analysis. r-ORAM’s recursive approach is general in that it can be applied to all recent tree ORAMs, both constant and poly-log client memory ORAMs. Finally, we implement and benchmark r-ORAM in a practical setting to back up our theoretical claims.

Tree Transduction Tools for Cdec

Directory of Open Access Journals (Sweden)

Austin Matthews

2014-09-01

Full Text Available We describe a collection of open source tools for learning tree-to-string and tree-to-tree transducers and the extensions to the cdec decoder that enable translation with these. Our modular, easy-to-extend tools extract rules from trees or forests aligned to strings and trees subject to different structural constraints. A fast, multithreaded implementation of the Cohn and Blunsom (2009 model for extracting compact tree-to-string rules is also included. The implementation of the tree composition algorithm used by cdec is described, and translation quality and decoding time results are presented. Our experimental results add to the body of evidence suggesting that tree transducers are a compelling option for translation, particularly when decoding speed and translation model size are important.

City of Pittsburgh Trees

Data.gov (United States)

Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Trees cared for and managed by the City of Pittsburgh Department of Public Works Forestry Division. Tree Benefits are calculated using the National Tree Benefit...

Flowering Trees

Indian Academy of Sciences (India)

user

Flowering Trees. Gliricidia sepium(Jacq.) Kunta ex Walp. (Quickstick) of Fabaceae is a small deciduous tree with. Pinnately compound leaves. Flower are prroduced in large number in early summer on terminal racemes. They are attractive, pinkish-white and typically like bean flowers. Fruit is a few-seeded flat pod.

Drawing Trees

DEFF Research Database (Denmark)

Halkjær From, Andreas; Schlichtkrull, Anders; Villadsen, Jørgen

2018-01-01

We formally prove in Isabelle/HOL two properties of an algorithm for laying out trees visually. The first property states that removing layout annotations recovers the original tree. The second property states that nodes are placed at least a unit of distance apart. We have yet to formalize three...

Interspecific variation in tree seedlings establishment in canopy gaps in relation to tree density

Energy Technology Data Exchange (ETDEWEB)

Reader, R.J.; Bonser, S.P.; Duralia, T.E.; Bricker, B.D. [Guelph Univ., ON (Canada). Dept. of Botany

1995-10-01

We tested whether interspecific variation in tree seedling establishment in canopy gaps was significantly related to interspecific variation in tree density, for seven deciduous forest tree species (Quercus alba, Hamamelis virginiana, Acer rubrum, Sassafras albidum, Quercus rubra, Prunus serotina, Ostrya virginiana). For each species, seedling establishment was calculated as the difference in seedling density before experimental gap creation versus three years after gap creation. In each of the six experimentally-created gap types (33% or 66% removal of tree basal area from 0.01ha, 0.05ha or 0.20ha patches), differences in seedling establishment among species were significantly related to differences in their density in the tree canopy. A regression model with log{sub e} tree density as the independent variable accounted for between 93% and 98% of interspecific variation in seedling establishment. Our results provide empirical support for models of tree dynamics in gaps that assume seedling establishment depends on canopy tree density. 17 refs, 1 fig, 3 tabs

Phylogenetic trees in bioinformatics

Energy Technology Data Exchange (ETDEWEB)

Burr, Tom L [Los Alamos National Laboratory

2008-01-01

Genetic data is often used to infer evolutionary relationships among a collection of viruses, bacteria, animal or plant species, or other operational taxonomic units (OTU). A phylogenetic tree depicts such relationships and provides a visual representation of the estimated branching order of the OTUs. Tree estimation is unique for several reasons, including: the types of data used to represent each OTU; the use ofprobabilistic nucleotide substitution models; the inference goals involving both tree topology and branch length, and the huge number of possible trees for a given sample of a very modest number of OTUs, which implies that fmding the best tree(s) to describe the genetic data for each OTU is computationally demanding. Bioinformatics is too large a field to review here. We focus on that aspect of bioinformatics that includes study of similarities in genetic data from multiple OTUs. Although research questions are diverse, a common underlying challenge is to estimate the evolutionary history of the OTUs. Therefore, this paper reviews the role of phylogenetic tree estimation in bioinformatics, available methods and software, and identifies areas for additional research and development.

Fast Tree: Computing Large Minimum-Evolution Trees with Profiles instead of a Distance Matrix

OpenAIRE

N. Price, Morgan

2009-01-01

Gene families are growing rapidly, but standard methods for inferring phylogenies do not scale to alignments with over 10,000 sequences. We present FastTree, a method for constructing large phylogenies and for estimating their reliability. Instead of storing a distance matrix, FastTree stores sequence profiles of internal nodes in the tree. FastTree uses these profiles to implement neighbor-joining and uses heuristics to quickly identify candidate joins. FastTree then uses nearest-neighbor i...

FastTree: Computing Large Minimum Evolution Trees with Profiles instead of a Distance Matrix

OpenAIRE

Price, Morgan N.; Dehal, Paramvir S.; Arkin, Adam P.

2009-01-01

Gene families are growing rapidly, but standard methods for inferring phylogenies do not scale to alignments with over 10,000 sequences. We present FastTree, a method for constructing large phylogenies and for estimating their reliability. Instead of storing a distance matrix, FastTree stores sequence profiles of internal nodes in the tree. FastTree uses these profiles to implement Neighbor-Joining and uses heuristics to quickly identify candidate joins. FastTree then uses nearest neighbor in...

Flowering Trees

Indian Academy of Sciences (India)

Flowering Trees. Acrocarpus fraxinifolius Wight & Arn. (PINK CEDAR, AUSTRALIAN ASH) of. Caesalpiniaceae is a lofty unarmed deciduous native tree that attains a height of 30–60m with buttresses. Bark is thin and light grey. Leaves are compound and bright red when young. Flowers in dense, erect, axillary racemes.

On Tree-Based Phylogenetic Networks.

Science.gov (United States)

Zhang, Louxin

2016-07-01

A large class of phylogenetic networks can be obtained from trees by the addition of horizontal edges between the tree edges. These networks are called tree-based networks. We present a simple necessary and sufficient condition for tree-based networks and prove that a universal tree-based network exists for any number of taxa that contains as its base every phylogenetic tree on the same set of taxa. This answers two problems posted by Francis and Steel recently. A byproduct is a computer program for generating random binary phylogenetic networks under the uniform distribution model.

A Metric on Phylogenetic Tree Shapes.

Science.gov (United States)

Colijn, C; Plazzotta, G

2018-01-01

The shapes of evolutionary trees are influenced by the nature of the evolutionary process but comparisons of trees from different processes are hindered by the challenge of completely describing tree shape. We present a full characterization of the shapes of rooted branching trees in a form that lends itself to natural tree comparisons. We use this characterization to define a metric, in the sense of a true distance function, on tree shapes. The metric distinguishes trees from random models known to produce different tree shapes. It separates trees derived from tropical versus USA influenza A sequences, which reflect the differing epidemiology of tropical and seasonal flu. We describe several metrics based on the same core characterization, and illustrate how to extend the metric to incorporate trees' branch lengths or other features such as overall imbalance. Our approach allows us to construct addition and multiplication on trees, and to create a convex metric on tree shapes which formally allows computation of average tree shapes. © The Author(s) 2017. Published by Oxford University Press, on behalf of the Society of Systematic Biologists.

Visualizing phylogenetic tree landscapes.

Science.gov (United States)

Wilgenbusch, James C; Huang, Wen; Gallivan, Kyle A

2017-02-02

Genomic-scale sequence alignments are increasingly used to infer phylogenies in order to better understand the processes and patterns of evolution. Different partitions within these new alignments (e.g., genes, codon positions, and structural features) often favor hundreds if not thousands of competing phylogenies. Summarizing and comparing phylogenies obtained from multi-source data sets using current consensus tree methods discards valuable information and can disguise potential methodological problems. Discovery of efficient and accurate dimensionality reduction methods used to display at once in 2- or 3- dimensions the relationship among these competing phylogenies will help practitioners diagnose the limits of current evolutionary models and potential problems with phylogenetic reconstruction methods when analyzing large multi-source data sets. We introduce several dimensionality reduction methods to visualize in 2- and 3-dimensions the relationship among competing phylogenies obtained from gene partitions found in three mid- to large-size mitochondrial genome alignments. We test the performance of these dimensionality reduction methods by applying several goodness-of-fit measures. The intrinsic dimensionality of each data set is also estimated to determine whether projections in 2- and 3-dimensions can be expected to reveal meaningful relationships among trees from different data partitions. Several new approaches to aid in the comparison of different phylogenetic landscapes are presented. Curvilinear Components Analysis (CCA) and a stochastic gradient decent (SGD) optimization method give the best representation of the original tree-to-tree distance matrix for each of the three- mitochondrial genome alignments and greatly outperformed the method currently used to visualize tree landscapes. The CCA + SGD method converged at least as fast as previously applied methods for visualizing tree landscapes. We demonstrate for all three mtDNA alignments that 3D

Human decision error (HUMDEE) trees

International Nuclear Information System (INIS)

Ostrom, L.T.

1993-01-01

Graphical presentations of human actions in incident and accident sequences have been used for many years. However, for the most part, human decision making has been underrepresented in these trees. This paper presents a method of incorporating the human decision process into graphical presentations of incident/accident sequences. This presentation is in the form of logic trees. These trees are called Human Decision Error Trees or HUMDEE for short. The primary benefit of HUMDEE trees is that they graphically illustrate what else the individuals involved in the event could have done to prevent either the initiation or continuation of the event. HUMDEE trees also present the alternate paths available at the operator decision points in the incident/accident sequence. This is different from the Technique for Human Error Rate Prediction (THERP) event trees. There are many uses of these trees. They can be used for incident/accident investigations to show what other courses of actions were available and for training operators. The trees also have a consequence component so that not only the decision can be explored, also the consequence of that decision

Tree felling: a necessary evil

CERN Multimedia

CERN Bulletin

2013-01-01

CERN started a campaign of tree felling in 2010 for safety reasons, and it will continue this year in various parts of the Meyrin site. As in previous years, the trees cut down in 2013 will be recycled and some will be replaced.   Diseased tree that had to be cut down on the Meyrin site. In association with the Geneva nature and countryside directorate (Direction générale de la nature et du paysage, DGNP), CERN commissioned the Geneva school of landscaping, engineering and architecture (Haute école du paysage, d’ingénierie et d’architecture, HEPIA) to compile an inventory of the trees on the Meyrin site. In total, 1285 trees (excluding poplars) were recorded. 75.5% of these trees were declared to be in a good state of health (i.e. 971 trees), 21.5% in a moderate state of health (276 trees) and 3% in a poor state of health (38 trees). As for the poplars, the 236 specimens recorded on the Meyrin site were judged to be too old, to...

Per tree estimates with n-tree distance sampling: an application to increment core data

Science.gov (United States)

Thomas B. Lynch; Robert F. Wittwer

2002-01-01

Per tree estimates using the n trees nearest a point can be obtained by using a ratio of per unit area estimates from n-tree distance sampling. This ratio was used to estimate average age by d.b.h. classes for cottonwood trees (Populus deltoides Bartr. ex Marsh.) on the Cimarron National Grassland. Increment...

Interactive Tree Of Life v2: online annotation and display of phylogenetic trees made easy.

Science.gov (United States)

Letunic, Ivica; Bork, Peer

2011-07-01

Interactive Tree Of Life (http://itol.embl.de) is a web-based tool for the display, manipulation and annotation of phylogenetic trees. It is freely available and open to everyone. In addition to classical tree viewer functions, iTOL offers many novel ways of annotating trees with various additional data. Current version introduces numerous new features and greatly expands the number of supported data set types. Trees can be interactively manipulated and edited. A free personal account system is available, providing management and sharing of trees in user defined workspaces and projects. Export to various bitmap and vector graphics formats is supported. Batch access interface is available for programmatic access or inclusion of interactive trees into other web services.

Maximum Gene-Support Tree

Directory of Open Access Journals (Sweden)

Yunfeng Shan

2008-01-01

Full Text Available Genomes and genes diversify during evolution; however, it is unclear to what extent genes still retain the relationship among species. Model species for molecular phylogenetic studies include yeasts and viruses whose genomes were sequenced as well as plants that have the fossil-supported true phylogenetic trees available. In this study, we generated single gene trees of seven yeast species as well as single gene trees of nine baculovirus species using all the orthologous genes among the species compared. Homologous genes among seven known plants were used for validation of the finding. Four algorithms—maximum parsimony (MP, minimum evolution (ME, maximum likelihood (ML, and neighbor-joining (NJ—were used. Trees were reconstructed before and after weighting the DNA and protein sequence lengths among genes. Rarely a gene can always generate the “true tree” by all the four algorithms. However, the most frequent gene tree, termed “maximum gene-support tree” (MGS tree, or WMGS tree for the weighted one, in yeasts, baculoviruses, or plants was consistently found to be the “true tree” among the species. The results provide insights into the overall degree of divergence of orthologous genes of the genomes analyzed and suggest the following: 1 The true tree relationship among the species studied is still maintained by the largest group of orthologous genes; 2 There are usually more orthologous genes with higher similarities between genetically closer species than between genetically more distant ones; and 3 The maximum gene-support tree reflects the phylogenetic relationship among species in comparison.

Tree Rings: Timekeepers of the Past.

Science.gov (United States)

Phipps, R. L.; McGowan, J.

One of a series of general interest publications on science issues, this booklet describes the uses of tree rings in historical and biological recordkeeping. Separate sections cover the following topics: dating of tree rings, dating with tree rings, tree ring formation, tree ring identification, sample collections, tree ring cross dating, tree…

Flowering Trees

Indian Academy of Sciences (India)

Cassia siamia Lamk. (Siamese tree senna) of Caesalpiniaceae is a small or medium size handsome tree. Leaves are alternate, pinnately compound and glandular, upto 18 cm long with 8–12 pairs of leaflets. Inflorescence is axillary or terminal and branched. Flowering lasts for a long period from March to February. Fruit is ...

Flowering Trees

Indian Academy of Sciences (India)

Flowering Trees. Cerbera manghasL. (SEA MANGO) of Apocynaceae is a medium-sized evergreen coastal tree with milky latex. The bark is grey-brown, thick and ... Fruit is large. (5–10 cm long), oval containing two flattened seeds and resembles a mango, hence the name Mangas or. Manghas. Leaves and fruits contain ...

Talking Trees

Science.gov (United States)

Tolman, Marvin

2005-01-01

Students love outdoor activities and will love them even more when they build confidence in their tree identification and measurement skills. Through these activities, students will learn to identify the major characteristics of trees and discover how the pace--a nonstandard measuring unit--can be used to estimate not only distances but also the…

ELB-trees an efficient and lock-free B-tree derivative

DEFF Research Database (Denmark)

Bonnichsen, Lars Frydendal; Karlsson, Sven; Probst, Christian W.

2013-01-01

overhead. All lock-free data structures are based on simple atomic operations that, though supported by modern processors, are expensive in execution time. We present a lock-free data structure, ELB-trees, which under certain assumptions can be used as multimaps as well as priority queues. Specifically...... it cannot store duplicate key-value pairs, and it is not linearizable. Compared to existing data structures, ELB-trees require fewer atomic operations leading to improved performance. We measure the parallel performance of ELB-trees using a set of benchmarks and observe that ELB-trees are up to almost 30......As computer systems scale in the number of processors, scalable data structures with good parallel performance become increasingly important. Lock-free data structures promise such improved parallel performance at the expense of higher algorithmic complexity and higher sequential execution time...

A support vector machine based test for incongruence between sets of trees in tree space

Science.gov (United States)

2012-01-01

Background The increased use of multi-locus data sets for phylogenetic reconstruction has increased the need to determine whether a set of gene trees significantly deviate from the phylogenetic patterns of other genes. Such unusual gene trees may have been influenced by other evolutionary processes such as selection, gene duplication, or horizontal gene transfer. Results Motivated by this problem we propose a nonparametric goodness-of-fit test for two empirical distributions of gene trees, and we developed the software GeneOut to estimate a p-value for the test. Our approach maps trees into a multi-dimensional vector space and then applies support vector machines (SVMs) to measure the separation between two sets of pre-defined trees. We use a permutation test to assess the significance of the SVM separation. To demonstrate the performance of GeneOut, we applied it to the comparison of gene trees simulated within different species trees across a range of species tree depths. Applied directly to sets of simulated gene trees with large sample sizes, GeneOut was able to detect very small differences between two set of gene trees generated under different species trees. Our statistical test can also include tree reconstruction into its test framework through a variety of phylogenetic optimality criteria. When applied to DNA sequence data simulated from different sets of gene trees, results in the form of receiver operating characteristic (ROC) curves indicated that GeneOut performed well in the detection of differences between sets of trees with different distributions in a multi-dimensional space. Furthermore, it controlled false positive and false negative rates very well, indicating a high degree of accuracy. Conclusions The non-parametric nature of our statistical test provides fast and efficient analyses, and makes it an applicable test for any scenario where evolutionary or other factors can lead to trees with different multi-dimensional distributions. The

Atlas of United States Trees, Volume 2: Alaska Trees and Common Shrubs.

Science.gov (United States)

Viereck, Leslie A.; Little, Elbert L., Jr.

This volume is the second in a series of atlases describing the natural distribution or range of native tree species in the United States. The 82 species maps include 32 of trees in Alaska, 6 of shrubs rarely reaching tree size, and 44 more of common shrubs. More than 20 additional maps summarize environmental factors and furnish general…

Colourings of (k-r,k-trees

Directory of Open Access Journals (Sweden)

M. Borowiecki

2017-01-01

Full Text Available Trees are generalized to a special kind of higher dimensional complexes known as \\((j,k\\-trees ([L. W. Beineke, R. E. Pippert, On the structure of \\((m,n\\-trees, Proc. 8th S-E Conf. Combinatorics, Graph Theory and Computing, 1977, 75-80], and which are a natural extension of \\(k\\-trees for \\(j=k-1\\. The aim of this paper is to study\\((k-r,k\\-trees ([H. P. Patil, Studies on \\(k\\-trees and some related topics, PhD Thesis, University of Warsaw, Poland, 1984], which are a generalization of \\(k\\-trees (or usual trees when \\(k=1\\. We obtain the chromatic polynomial of \\((k-r,k\\-trees and show that any two \\((k-r,k\\-trees of the same order are chromatically equivalent. However, if \\(r\

The valuative tree

CERN Document Server

Favre, Charles

2004-01-01

This volume is devoted to a beautiful object, called the valuative tree and designed as a powerful tool for the study of singularities in two complex dimensions. Its intricate yet manageable structure can be analyzed by both algebraic and geometric means. Many types of singularities, including those of curves, ideals, and plurisubharmonic functions, can be encoded in terms of positive measures on the valuative tree. The construction of these measures uses a natural tree Laplace operator of independent interest.

A recursive algorithm for trees and forests

OpenAIRE

Guo, Song; Guo, Victor J. W.

2017-01-01

Trees or rooted trees have been generously studied in the literature. A forest is a set of trees or rooted trees. Here we give recurrence relations between the number of some kind of rooted forest with $k$ roots and that with $k+1$ roots on $\\{1,2,\\ldots,n\\}$. Classical formulas for counting various trees such as rooted trees, bipartite trees, tripartite trees, plane trees, $k$-ary plane trees, $k$-edge colored trees follow immediately from our recursive relations.

Understanding recruitment failure in tropical tree species: Insights from a tree ring study

NARCIS (Netherlands)

Vlam, M.; Baker, P.J.; Bunyavejchewin, S.; Mohren, G.M.J.; Zuidema, P.A.

2014-01-01

Many tropical tree species have population structures that exhibit strong recruitment failure. While the presence of adult trees indicates that appropriate regeneration conditions occurred in the past, it is often unclear why small individuals are absent. Knowing how, when and where these tree

Attack Trees with Sequential Conjunction

NARCIS (Netherlands)

Jhawar, Ravi; Kordy, Barbara; Mauw, Sjouke; Radomirović, Sasa; Trujillo-Rasua, Rolando

2015-01-01

We provide the first formal foundation of SAND attack trees which are a popular extension of the well-known attack trees. The SAND at- tack tree formalism increases the expressivity of attack trees by intro- ducing the sequential conjunctive operator SAND. This operator enables the modeling of

Spatial and temporal distribution of trunk-injected 14C-Imidacloprid in Fraxinus trees

Science.gov (United States)

Sara R. Tanis; Bert M. Cregg; David Mota-Sanchez; Deborah G. McCullough; Therese M. Poland

2012-01-01

BACKGROUND: Since the discovery of Agrilus planipennis Fairmaire (emerald ash borer) in 2002, researchers have tested several methods of chemical control. Soil drench or trunk injection products containing imidacloprid are commonly used to control adults. However, efficacy can be highly variable andmay be due to uneven translocation of systemic...

Tree Size Comparison of Some Important Street Trees Growing at ...

African Journals Online (AJOL)

PROF HORSFALL

More research is needed on these trees for healthy environment of city. The present ..... use and CO2 emissions from power plants. Environ. Poll. .... Anna. Bot., 65:567-574. Kozlowski, T.T., 1971. Growth and Development of. Trees. Vol. 1.

Flowering Trees

Indian Academy of Sciences (India)

medium-sized handsome tree with a straight bole that branches at the top. Leaves are once pinnate, with two to three pairs of leaflets. Young parts of the tree are velvety. Inflorescence is a branched raceme borne at the branch ends. Flowers are large, white, attractive, and fragrant. Corolla is funnel-shaped. Fruit is an ...

Flowering Trees

Indian Academy of Sciences (India)

Srimath

Grevillea robusta A. Cunn. ex R. Br. (Sil- ver Oak) of Proteaceae is a daintily lacy ornamental tree while young and growing into a mighty tree (45 m). Young shoots are silvery grey and the leaves are fern- like. Flowers are golden-yellow in one- sided racemes (10 cm). Fruit is a boat- shaped, woody follicle.

Mathematical foundations of event trees

International Nuclear Information System (INIS)

Papazoglou, Ioannis A.

1998-01-01

A mathematical foundation from first principles of event trees is presented. The main objective of this formulation is to offer a formal basis for developing automated computer assisted construction techniques for event trees. The mathematical theory of event trees is based on the correspondence between the paths of the tree and the elements of the outcome space of a joint event. The concept of a basic cylinder set is introduced to describe joint event outcomes conditional on specific outcomes of basic events or unconditional on the outcome of basic events. The concept of outcome space partition is used to describe the minimum amount of information intended to be preserved by the event tree representation. These concepts form the basis for an algorithm for systematic search for and generation of the most compact (reduced) form of an event tree consistent with the minimum amount of information the tree should preserve. This mathematical foundation allows for the development of techniques for automated generation of event trees corresponding to joint events which are formally described through other types of graphical models. Such a technique has been developed for complex systems described by functional blocks and it is reported elsewhere. On the quantification issue of event trees, a formal definition of a probability space corresponding to the event tree outcomes is provided. Finally, a short discussion is offered on the relationship of the presented mathematical theory with the more general use of event trees in reliability analysis of dynamic systems

Stand conditions and tree characteristics affect quality of longleaf pine for red-cockaded woodpecker cavity trees

Science.gov (United States)

W.G. Ross; D.L. Kulhavy; R.N. Conner

1997-01-01

We measured resin flow of longleaf (Pinus palustris Mill.) pines in red-cockaded woodpecker (Picoides borealis Vieillot) clusters in the Angelina National Forest in Texas, and the Apalachicola National Forest in Florida. Sample trees were categorized as active cavity trees, inactive cavity trees and control trees. Sample trees were further...

Making CSB + -Trees Processor Conscious

DEFF Research Database (Denmark)

Samuel, Michael; Pedersen, Anders Uhl; Bonnet, Philippe

2005-01-01

of the CSB+-tree. We argue that it is necessary to consider a larger group of parameters in order to adapt CSB+-tree to processor architectures as different as Pentium and Itanium. We identify this group of parameters and study how it impacts the performance of CSB+-tree on Itanium 2. Finally, we propose......Cache-conscious indexes, such as CSB+-tree, are sensitive to the underlying processor architecture. In this paper, we focus on how to adapt the CSB+-tree so that it performs well on a range of different processor architectures. Previous work has focused on the impact of node size on the performance...... a systematic method for adapting CSB+-tree to new platforms. This work is a first step towards integrating CSB+-tree in MySQL’s heap storage manager....

Tree architecture and life-history strategies across 200 co-occurring tropical tree species

NARCIS (Netherlands)

Iida, Y.; Kohyama, T.S.; Kubo, T.; Kassim, A.R.; Poorter, L.; Sterck, F.J.; Potts, M.D.

2011-01-01

1. Tree architecture is thought to allow species to partition horizontal and vertical light gradients in the forest canopy. Tree architecture is closely related to light capture, carbon gain and the efficiency with which trees reach the canopy. Previous studies that investigated how light gradients

Total well dominated trees

DEFF Research Database (Denmark)

Finbow, Arthur; Frendrup, Allan; Vestergaard, Preben D.

cardinality then G is a total well dominated graph. In this paper we study composition and decomposition of total well dominated trees. By a reversible process we prove that any total well dominated tree can both be reduced to and constructed from a family of three small trees....

Recursive algorithms for phylogenetic tree counting.

Science.gov (United States)

Gavryushkina, Alexandra; Welch, David; Drummond, Alexei J

2013-10-28

In Bayesian phylogenetic inference we are interested in distributions over a space of trees. The number of trees in a tree space is an important characteristic of the space and is useful for specifying prior distributions. When all samples come from the same time point and no prior information available on divergence times, the tree counting problem is easy. However, when fossil evidence is used in the inference to constrain the tree or data are sampled serially, new tree spaces arise and counting the number of trees is more difficult. We describe an algorithm that is polynomial in the number of sampled individuals for counting of resolutions of a constraint tree assuming that the number of constraints is fixed. We generalise this algorithm to counting resolutions of a fully ranked constraint tree. We describe a quadratic algorithm for counting the number of possible fully ranked trees on n sampled individuals. We introduce a new type of tree, called a fully ranked tree with sampled ancestors, and describe a cubic time algorithm for counting the number of such trees on n sampled individuals. These algorithms should be employed for Bayesian Markov chain Monte Carlo inference when fossil data are included or data are serially sampled.

New perspectives on the ecology of tree structure and tree communities through terrestrial laser scanning.

Science.gov (United States)

Malhi, Yadvinder; Jackson, Tobias; Patrick Bentley, Lisa; Lau, Alvaro; Shenkin, Alexander; Herold, Martin; Calders, Kim; Bartholomeus, Harm; Disney, Mathias I

2018-04-06

Terrestrial laser scanning (TLS) opens up the possibility of describing the three-dimensional structures of trees in natural environments with unprecedented detail and accuracy. It is already being extensively applied to describe how ecosystem biomass and structure vary between sites, but can also facilitate major advances in developing and testing mechanistic theories of tree form and forest structure, thereby enabling us to understand why trees and forests have the biomass and three-dimensional structure they do. Here we focus on the ecological challenges and benefits of understanding tree form, and highlight some advances related to capturing and describing tree shape that are becoming possible with the advent of TLS. We present examples of ongoing work that applies, or could potentially apply, new TLS measurements to better understand the constraints on optimization of tree form. Theories of resource distribution networks, such as metabolic scaling theory, can be tested and further refined. TLS can also provide new approaches to the scaling of woody surface area and crown area, and thereby better quantify the metabolism of trees. Finally, we demonstrate how we can develop a more mechanistic understanding of the effects of avoidance of wind risk on tree form and maximum size. Over the next few years, TLS promises to deliver both major empirical and conceptual advances in the quantitative understanding of trees and tree-dominated ecosystems, leading to advances in understanding the ecology of why trees and ecosystems look and grow the way they do.

Tree manipulation experiment

Science.gov (United States)

Nishina, K.; Takenaka, C.; Ishizuka, S.; Hashimoto, S.; Yagai, Y.

2012-12-01

Some forest operations such as thinning and harvesting management could cause changes in N cycling and N2O emission from soils, since thinning and harvesting managements are accompanied with changes in aboveground environments such as an increase of slash falling and solar radiation on the forest floor. However, a considerable uncertainty exists in effects of thinning and harvesting on N2O fluxes regarding changes in belowground environments by cutting trees. To focus on the effect of changes in belowground environments on the N2O emissions from soils, we conducted a tree manipulation experiment in Japanese cedar (Cryptomeria japonica) stand without soil compaction and slash falling near the chambers and measured N2O flux at 50 cm and 150 cm distances from the tree trunk (stump) before and after cutting. We targeted 5 trees for the manipulation and established the measurement chambers to the 4 directions around each targeted tree relative to upper slope (upper, left, right, lower positions). We evaluated the effect of logging on the emission by using hierarchical Bayesian model. HB model can evaluate the variability in observed data and their uncertainties in the estimation with various probability distributions. Moreover, the HB model can easily accommodate the non-linear relationship among the N2O emissions and the environmental factors, and explicitly take non-independent data (nested structure of data) for the estimation into account by using random effects in the model. Our results showed tree cutting stimulated N2O emission from soils, and also that the increase of N2O flux depended on the distance from the trunk (stump): the increase of N2O flux at 50 cm from the trunk (stump) was greater than that of 150 cm from the trunk. The posterior simulation of the HB model indicated that the stimulation of N2O emission by tree cut- ting could reach up to 200 cm in our experimental plot. By tree cutting, the estimated N2O emission at 0-40 cm from the trunk doubled

The Re-Think Tree.

Science.gov (United States)

Gear, Jim

1993-01-01

The Re-Think Tree is a simple framework to help individuals assess and improve their behaviors related to environmental issues. The branches of the tree in order of priority are refuse, reduce, re-use, and recycle. Roots of the tree include such things as public opinion, education, and watchdog groups. (KS)

Coalescent-based species tree inference from gene tree topologies under incomplete lineage sorting by maximum likelihood.

Science.gov (United States)

Wu, Yufeng

2012-03-01

Incomplete lineage sorting can cause incongruence between the phylogenetic history of genes (the gene tree) and that of the species (the species tree), which can complicate the inference of phylogenies. In this article, I present a new coalescent-based algorithm for species tree inference with maximum likelihood. I first describe an improved method for computing the probability of a gene tree topology given a species tree, which is much faster than an existing algorithm by Degnan and Salter (2005). Based on this method, I develop a practical algorithm that takes a set of gene tree topologies and infers species trees with maximum likelihood. This algorithm searches for the best species tree by starting from initial species trees and performing heuristic search to obtain better trees with higher likelihood. This algorithm, called STELLS (which stands for Species Tree InfErence with Likelihood for Lineage Sorting), has been implemented in a program that is downloadable from the author's web page. The simulation results show that the STELLS algorithm is more accurate than an existing maximum likelihood method for many datasets, especially when there is noise in gene trees. I also show that the STELLS algorithm is efficient and can be applied to real biological datasets. © 2011 The Author. Evolution© 2011 The Society for the Study of Evolution.

Coded Splitting Tree Protocols

DEFF Research Database (Denmark)

Sørensen, Jesper Hemming; Stefanovic, Cedomir; Popovski, Petar

2013-01-01

This paper presents a novel approach to multiple access control called coded splitting tree protocol. The approach builds on the known tree splitting protocols, code structure and successive interference cancellation (SIC). Several instances of the tree splitting protocol are initiated, each...... instance is terminated prematurely and subsequently iterated. The combined set of leaves from all the tree instances can then be viewed as a graph code, which is decodable using belief propagation. The main design problem is determining the order of splitting, which enables successful decoding as early...

Drawing Contour Trees in the Plane.

Science.gov (United States)

Heine, C; Schneider, D; Carr, Hamish; Scheuermann, G

2011-11-01

The contour tree compactly describes scalar field topology. From the viewpoint of graph drawing, it is a tree with attributes at vertices and optionally on edges. Standard tree drawing algorithms emphasize structural properties of the tree and neglect the attributes. Applying known techniques to convey this information proves hard and sometimes even impossible. We present several adaptions of popular graph drawing approaches to the problem of contour tree drawing and evaluate them. We identify five esthetic criteria for drawing contour trees and present a novel algorithm for drawing contour trees in the plane that satisfies four of these criteria. Our implementation is fast and effective for contour tree sizes usually used in interactive systems (around 100 branches) and also produces readable pictures for larger trees, as is shown for an 800 branch example.

Minnesota's Forest Trees. Revised.

Science.gov (United States)

Miles, William R.; Fuller, Bruce L.

This bulletin describes 46 of the more common trees found in Minnesota's forests and windbreaks. The bulletin contains two tree keys, a summer key and a winter key, to help the reader identify these trees. Besides the two keys, the bulletin includes an introduction, instructions for key use, illustrations of leaf characteristics and twig…

Covering tree with stars

DEFF Research Database (Denmark)

Baumbach, Jan; Guo, Jian-Ying; Ibragimov, Rashid

2013-01-01

We study the tree edit distance problem with edge deletions and edge insertions as edit operations. We reformulate a special case of this problem as Covering Tree with Stars (CTS): given a tree T and a set of stars, can we connect the stars in by adding edges between them such that the resulting ...

DIF Trees: Using Classification Trees to Detect Differential Item Functioning

Science.gov (United States)

Vaughn, Brandon K.; Wang, Qiu

2010-01-01

A nonparametric tree classification procedure is used to detect differential item functioning for items that are dichotomously scored. Classification trees are shown to be an alternative procedure to detect differential item functioning other than the use of traditional Mantel-Haenszel and logistic regression analysis. A nonparametric…

Picking a tree: habitat use by the tree agama, Acanthocercus ...

African Journals Online (AJOL)

We studied tree agama (Acanthocercus a. atricollis) habitat use in the Magaliesberg mountain range in northern South Africa using sightings of marked individuals, and in a few cases, radio-telemetry. Acanthocercus a. atricollis preferentially selected thorn trees (46%; Acacia karroo), followed by common sugarbush (10%; ...

Multi-level tree analysis of pulmonary artery/vein trees in non-contrast CT images

Science.gov (United States)

Gao, Zhiyun; Grout, Randall W.; Hoffman, Eric A.; Saha, Punam K.

2012-02-01

Diseases like pulmonary embolism and pulmonary hypertension are associated with vascular dystrophy. Identifying such pulmonary artery/vein (A/V) tree dystrophy in terms of quantitative measures via CT imaging significantly facilitates early detection of disease or a treatment monitoring process. A tree structure, consisting of nodes and connected arcs, linked to the volumetric representation allows multi-level geometric and volumetric analysis of A/V trees. Here, a new theory and method is presented to generate multi-level A/V tree representation of volumetric data and to compute quantitative measures of A/V tree geometry and topology at various tree hierarchies. The new method is primarily designed on arc skeleton computation followed by a tree construction based topologic and geometric analysis of the skeleton. The method starts with a volumetric A/V representation as input and generates its topologic and multi-level volumetric tree representations long with different multi-level morphometric measures. A new recursive merging and pruning algorithms are introduced to detect bad junctions and noisy branches often associated with digital geometric and topologic analysis. Also, a new notion of shortest axial path is introduced to improve the skeletal arc joining two junctions. The accuracy of the multi-level tree analysis algorithm has been evaluated using computer generated phantoms and pulmonary CT images of a pig vessel cast phantom while the reproducibility of method is evaluated using multi-user A/V separation of in vivo contrast-enhanced CT images of a pig lung at different respiratory volumes.

The national tree-list layer

Science.gov (United States)

Stacy A. Drury; Jason M. Herynk

2011-01-01

The National Tree-List Layer (NTLL) project used LANDFIRE map products to produce the first national tree-list map layer that represents tree populations at stand and regional levels. The NTLL was produced in a short time frame to address the needs of Fire and Aviation Management for a map layer that could be used as input for simulating fire-caused tree mortality...

Beyond Tree Throw: Wind, Water, Rock and the Mechanics of Tree-Driven Bedrock Physical Weathering

Science.gov (United States)

Marshall, J. A.; Anderson, R. S.; Dawson, T. E.; Dietrich, W. E.; Minear, J. T.

2017-12-01

Tree throw is often invoked as the dominant process in converting bedrock to soil and thus helping to build the Critical Zone (CZ). In addition, observations of tree roots lifting sidewalk slabs, occupying cracks, and prying slabs of rock from cliff faces have led to a general belief in the power of plant growth forces. These common observations have led to conceptual models with trees at the center of the soil genesis process. This is despite the observation that tree throw is rare in many forested settings, and a dearth of field measurements that quantify the magnitude of growth forces. While few trees blow down, every tree grows roots, inserting many tens of percent of its mass below ground. Yet we lack data quantifying the role of trees in both damaging bedrock and detaching it (and thus producing soil). By combing force measurements at the tree-bedrock interface with precipitation, solar radiation, wind speed, and wind-driven tree sway data we quantified the magnitude and frequency of tree-driven soil-production mechanisms from two contrasting climatic and lithologic regimes (Boulder and Eel Creek CZ Observatories). Preliminary data suggests that in settings with relatively thin soils, trees can damage and detach rock due to diurnal fluctuations, wind response and rainfall events. Surprisingly, our data suggests that forces from roots and trunks growing against bedrock are insufficient to pry rock apart or damage bedrock although much more work is needed in this area. The frequency, magnitude and style of wind-driven tree forces at the bedrock interface varies considerably from one to another species. This suggests that tree properties such as mass, elasticity, stiffness and branch structure determine whether trees respond to gusts big or small, move at the same frequency as large wind gusts, or are able to self-dampen near-ground sway response to extended wind forces. Our measurements of precipitation-driven and daily fluctuations in root pressures exerted on

Nonbinary Tree-Based Phylogenetic Networks.

Science.gov (United States)

Jetten, Laura; van Iersel, Leo

2018-01-01

Rooted phylogenetic networks are used to describe evolutionary histories that contain non-treelike evolutionary events such as hybridization and horizontal gene transfer. In some cases, such histories can be described by a phylogenetic base-tree with additional linking arcs, which can, for example, represent gene transfer events. Such phylogenetic networks are called tree-based. Here, we consider two possible generalizations of this concept to nonbinary networks, which we call tree-based and strictly-tree-based nonbinary phylogenetic networks. We give simple graph-theoretic characterizations of tree-based and strictly-tree-based nonbinary phylogenetic networks. Moreover, we show for each of these two classes that it can be decided in polynomial time whether a given network is contained in the class. Our approach also provides a new view on tree-based binary phylogenetic networks. Finally, we discuss two examples of nonbinary phylogenetic networks in biology and show how our results can be applied to them.

Submodular unsplittable flow on trees

DEFF Research Database (Denmark)

Adamaszek, Anna Maria; Chalermsook, Parinya; Ene, Alina

2016-01-01

We study the Unsplittable Flow problem (UFP) on trees with a submodular objective function. The input to this problem is a tree with edge capacities and a collection of tasks, each characterized by a source node, a sink node, and a demand. A subset of the tasks is feasible if the tasks can...... simultaneously send their demands from the source to the sink without violating the edge capacities. The goal is to select a feasible subset of the tasks that maximizes a submodular objective function. Our main result is an O(k log n)-approximation algorithm for Submodular UFP on trees where k denotes...... the pathwidth of the given tree. Since every tree has pathwidth O(log n), we obtain an O(log2 n) approximation for arbitrary trees. This is the first non-trivial approximation guarantee for the problem and it matches the best approximation known for UFP on trees with a linear objective function. Our main...

Tree Mortality Undercuts Ability of Tree-Planting Programs to Provide Benefits: Results of a Three-City Study

Directory of Open Access Journals (Sweden)

Sarah Widney

2016-03-01

Full Text Available Trees provide numerous benefits for urban residents, including reduced energy usage, improved air quality, stormwater management, carbon sequestration, and increased property values. Quantifying these benefits can help justify the costs of planting trees. In this paper, we use i-Tree Streets to quantify the benefits of street trees planted by nonprofits in three U.S. cities (Detroit, Michigan; Indianapolis, Indiana, and Philadelphia, Pennsylvania from 2009 to 2011. We also use both measured and modeled survival and growth rates to “grow” the tree populations 5 and 10 years into the future to project the future benefits of the trees under different survival and growth scenarios. The 4059 re-inventoried trees (2864 of which are living currently provide almost $40,000 (USD in estimated annual benefits ($9–$20/tree depending on the city, the majority (75% of which are increased property values. The trees can be expected to provide increasing annual benefits during the 10 years after planting if the annual survival rate is higher than the 93% annual survival measured during the establishment period. However, our projections show that with continued 93% or lower annual survival, the increase in annual benefits from tree growth will not be able to make up for the loss of benefits as trees die. This means that estimated total annual benefits from a cohort of planted trees will decrease between the 5-year projection and the 10-year projection. The results of this study indicate that without early intervention to ensure survival of planted street trees, tree mortality may be significantly undercutting the ability of tree-planting programs to provide benefits to neighborhood residents.

Coalescent methods for estimating phylogenetic trees.

Science.gov (United States)

Liu, Liang; Yu, Lili; Kubatko, Laura; Pearl, Dennis K; Edwards, Scott V

2009-10-01

We review recent models to estimate phylogenetic trees under the multispecies coalescent. Although the distinction between gene trees and species trees has come to the fore of phylogenetics, only recently have methods been developed that explicitly estimate species trees. Of the several factors that can cause gene tree heterogeneity and discordance with the species tree, deep coalescence due to random genetic drift in branches of the species tree has been modeled most thoroughly. Bayesian approaches to estimating species trees utilizes two likelihood functions, one of which has been widely used in traditional phylogenetics and involves the model of nucleotide substitution, and the second of which is less familiar to phylogeneticists and involves the probability distribution of gene trees given a species tree. Other recent parametric and nonparametric methods for estimating species trees involve parsimony criteria, summary statistics, supertree and consensus methods. Species tree approaches are an appropriate goal for systematics, appear to work well in some cases where concatenation can be misleading, and suggest that sampling many independent loci will be paramount. Such methods can also be challenging to implement because of the complexity of the models and computational time. In addition, further elaboration of the simplest of coalescent models will be required to incorporate commonly known issues such as deviation from the molecular clock, gene flow and other genetic forces.

Decision trees in epidemiological research.

Science.gov (United States)

Venkatasubramaniam, Ashwini; Wolfson, Julian; Mitchell, Nathan; Barnes, Timothy; JaKa, Meghan; French, Simone

2017-01-01

In many studies, it is of interest to identify population subgroups that are relatively homogeneous with respect to an outcome. The nature of these subgroups can provide insight into effect mechanisms and suggest targets for tailored interventions. However, identifying relevant subgroups can be challenging with standard statistical methods. We review the literature on decision trees, a family of techniques for partitioning the population, on the basis of covariates, into distinct subgroups who share similar values of an outcome variable. We compare two decision tree methods, the popular Classification and Regression tree (CART) technique and the newer Conditional Inference tree (CTree) technique, assessing their performance in a simulation study and using data from the Box Lunch Study, a randomized controlled trial of a portion size intervention. Both CART and CTree identify homogeneous population subgroups and offer improved prediction accuracy relative to regression-based approaches when subgroups are truly present in the data. An important distinction between CART and CTree is that the latter uses a formal statistical hypothesis testing framework in building decision trees, which simplifies the process of identifying and interpreting the final tree model. We also introduce a novel way to visualize the subgroups defined by decision trees. Our novel graphical visualization provides a more scientifically meaningful characterization of the subgroups identified by decision trees. Decision trees are a useful tool for identifying homogeneous subgroups defined by combinations of individual characteristics. While all decision tree techniques generate subgroups, we advocate the use of the newer CTree technique due to its simplicity and ease of interpretation.

SILVA tree viewer: interactive web browsing of the SILVA phylogenetic guide trees

OpenAIRE

Beccati, Alan; Gerken, Jan; Quast, Christian; Yilmaz, Pelin; Glöckner, Frank Oliver

2017-01-01

Background Phylogenetic trees are an important tool to study the evolutionary relationships among organisms. The huge amount of available taxa poses difficulties in their interactive visualization. This hampers the interaction with the users to provide feedback for the further improvement of the taxonomic framework. Results The SILVA Tree Viewer is a web application designed for visualizing large phylogenetic trees without requiring the download of any software tool or data files. The SILVA T...

Efficacy of Soil-Applied Neonicotinoid Insecticides for Long-term Protection Against Emerald Ash Borer (Coleoptera: Buprestidae).

Science.gov (United States)

Smitley, David R; Herms, Daniel A; Davis, Terrance W

2015-10-01

Protection of green ash trees (Fraxinus pennsylvanica Marshall) from the emerald ash borer (EAB), Agrilus planipennis Fairmaire, by soil applications of neonicotinoids (imidacloprid, clothianidin, and dinotefuran) was tested at five locations between 2005 and 2013. Application rate and spring versus fall application dates were evaluated in tests with neighborhood street trees and in one plantation of 65 ash trees. Insecticide treatments of ash trees at all five sites were initiated as the leading edge of the EAB invasion began to kill the first ash trees at each location. Trees were treated and evaluated at each site for 4 to 7 yr. Spring applications of imidacloprid were more efficacious than fall applications. Application rates of 0.8 g a.i./cm dbh or greater per year gave a higher level of protection and were more consistent than rates of 0.56 g a.i./cm dbh per year or less. The number of years between the first observation of canopy loss due to EAB and death of most of the control trees varied from three to seven years among test sites, depending on how many non-treated ash trees were nearby. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Estimation of Tree Cover in an Agricultural Parkland of Senegal Using Rule-Based Regression Tree Modeling

Directory of Open Access Journals (Sweden)

Stefanie M. Herrmann

2013-10-01

Full Text Available Field trees are an integral part of the farmed parkland landscape in West Africa and provide multiple benefits to the local environment and livelihoods. While field trees have received increasing interest in the context of strengthening resilience to climate variability and change, the actual extent of farmed parkland and spatial patterns of tree cover are largely unknown. We used the rule-based predictive modeling tool Cubist® to estimate field tree cover in the west-central agricultural region of Senegal. A collection of rules and associated multiple linear regression models was constructed from (1 a reference dataset of percent tree cover derived from very high spatial resolution data (2 m Orbview as the dependent variable, and (2 ten years of 10-day 250 m Moderate Resolution Imaging Spectrometer (MODIS Normalized Difference Vegetation Index (NDVI composites and derived phenological metrics as independent variables. Correlation coefficients between modeled and reference percent tree cover of 0.88 and 0.77 were achieved for training and validation data respectively, with absolute mean errors of 1.07 and 1.03 percent tree cover. The resulting map shows a west-east gradient from high tree cover in the peri-urban areas of horticulture and arboriculture to low tree cover in the more sparsely populated eastern part of the study area. A comparison of current (2000s tree cover along this gradient with historic cover as seen on Corona images reveals dynamics of change but also areas of remarkable stability of field tree cover since 1968. The proposed modeling approach can help to identify locations of high and low tree cover in dryland environments and guide ground studies and management interventions aimed at promoting the integration of field trees in agricultural systems.

Environmental tritium in trees

International Nuclear Information System (INIS)

Brown, R.M.

1979-01-01

The distribution of environmental tritium in the free water and organically bound hydrogen of trees growing in the vicinity of the Chalk River Nuclear Laboratories (CRNL) has been studied. The regional dispersal of HTO in the atmosphere has been observed by surveying the tritium content of leaf moisture. Measurement of the distribution of organically bound tritium in the wood of tree ring sequences has given information on past concentrations of HTO taken up by trees growing in the CRNL Liquid Waste Disposal Area. For samples at background environmental levels, cellulose separation and analysis was done. The pattern of bomb tritium in precipitation of 1955-68 was observed to be preserved in the organically bound tritium of a tree ring sequence. Reactor tritium was discernible in a tree growing at a distance of 10 km from CRNL. These techniques provide convenient means of monitoring dispersal of HTO from nuclear facilities. (author)

On the structure of path-like trees

OpenAIRE

Muntaner Batle, Francesc Antoni; Rius Font, Miquel

2007-01-01

We study the structure of path-like trees. In order to do this, we introduce a set of trees that we call expandable trees. In this paper we also generalize the concept of path-like trees and we call such generalization generalized path-like trees. As in the case of path-like trees, generalized path-like trees, have very nice labeling properties.

Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

Science.gov (United States)

Lemessa, Debissa; Hambäck, Peter A; Hylander, Kristoffer

2015-01-01

Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

Directory of Open Access Journals (Sweden)

Debissa Lemessa

Full Text Available Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

Gene-Tree Reconciliation with MUL-Trees to Resolve Polyploidy Events.

Science.gov (United States)

Gregg, W C Thomas; Ather, S Hussain; Hahn, Matthew W

2017-11-01

Polyploidy can have a huge impact on the evolution of species, and it is a common occurrence, especially in plants. The two types of polyploids-autopolyploids and allopolyploids-differ in the level of divergence between the genes that are brought together in the new polyploid lineage. Because allopolyploids are formed via hybridization, the homoeologous copies of genes within them are at least as divergent as orthologs in the parental species that came together to form them. This means that common methods for estimating the parental lineages of allopolyploidy events are not accurate, and can lead to incorrect inferences about the number of gene duplications and losses. Here, we have adapted an algorithm for topology-based gene-tree reconciliation to work with multi-labeled trees (MUL-trees). By definition, MUL-trees have some tips with identical labels, which makes them a natural representation of the genomes of polyploids. Using this new reconciliation algorithm we can: accurately place allopolyploidy events on a phylogeny, identify the parental lineages that hybridized to form allopolyploids, distinguish between allo-, auto-, and (in most cases) no polyploidy, and correctly count the number of duplications and losses in a set of gene trees. We validate our method using gene trees simulated with and without polyploidy, and revisit the history of polyploidy in data from the clades including both baker's yeast and bread wheat. Our re-analysis of the yeast data confirms the allopolyploid origin and parental lineages previously identified for this group. The method presented here should find wide use in the growing number of genomes from species with a history of polyploidy. [Polyploidy; reconciliation; whole-genome duplication.]. © The Author(s) 2017. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Shade Trees Spatial Distribution and Its Effect on Grains and Beverage Quality of Shaded Coffee Trees

Directory of Open Access Journals (Sweden)

Francisco José da Silva Neto

2018-01-01

Full Text Available Shading coffee trees has gained importance, especially among smallholders, as an option to improve the products’ quality, therefore acquiring place at the specialty coffee market, where consumers are willing to give bonus for quality. This work aims to evaluate the influence of shade trees’ spatial distribution among coffee trees’ agronomic characteristics, yield, and beans and cup quality of shaded coffee trees. The experimental design consisted of completely randomized blocks with six repetitions and four treatments: coffee trees on shade trees planting rows, distant one meter from the trunk; coffee trees on shade trees planting row, distant six meters from the trunk; and coffee plants between the rows of shade trees, parallel to the previous treatments. The parameters analyzed were plant height, canopy diameter, plagiotropic branches’ length, yield, coffee fruits’ phenological stage, ripe cherries’ Brix degree, percentage of black, unripe, and insect damaged beans, bean size, and beverage quality. Shade trees quickened coffee fruits’ phenological stage of coffee trees nearest to them. This point also showed the best beverage quality, except for overripe fruits. The remaining parameters evaluated were not affected by shade trees’ spatial distribution.

Decision trees in epidemiological research

Directory of Open Access Journals (Sweden)

Ashwini Venkatasubramaniam

2017-09-01

Full Text Available Abstract Background In many studies, it is of interest to identify population subgroups that are relatively homogeneous with respect to an outcome. The nature of these subgroups can provide insight into effect mechanisms and suggest targets for tailored interventions. However, identifying relevant subgroups can be challenging with standard statistical methods. Main text We review the literature on decision trees, a family of techniques for partitioning the population, on the basis of covariates, into distinct subgroups who share similar values of an outcome variable. We compare two decision tree methods, the popular Classification and Regression tree (CART technique and the newer Conditional Inference tree (CTree technique, assessing their performance in a simulation study and using data from the Box Lunch Study, a randomized controlled trial of a portion size intervention. Both CART and CTree identify homogeneous population subgroups and offer improved prediction accuracy relative to regression-based approaches when subgroups are truly present in the data. An important distinction between CART and CTree is that the latter uses a formal statistical hypothesis testing framework in building decision trees, which simplifies the process of identifying and interpreting the final tree model. We also introduce a novel way to visualize the subgroups defined by decision trees. Our novel graphical visualization provides a more scientifically meaningful characterization of the subgroups identified by decision trees. Conclusions Decision trees are a useful tool for identifying homogeneous subgroups defined by combinations of individual characteristics. While all decision tree techniques generate subgroups, we advocate the use of the newer CTree technique due to its simplicity and ease of interpretation.

Human action analysis with randomized trees

CERN Document Server

Yu, Gang; Liu, Zicheng

2014-01-01

This book will provide a comprehensive overview on human action analysis with randomized trees. It will cover both the supervised random trees and the unsupervised random trees. When there are sufficient amount of labeled data available, supervised random trees provides a fast method for space-time interest point matching. When labeled data is minimal as in the case of example-based action search, unsupervised random trees is used to leverage the unlabelled data. We describe how the randomized trees can be used for action classification, action detection, action search, and action prediction.

Edge-Disjoint Fibonacci Trees in Hypercube

Directory of Open Access Journals (Sweden)

Indhumathi Raman

2014-01-01

Full Text Available The Fibonacci tree is a rooted binary tree whose number of vertices admit a recursive definition similar to the Fibonacci numbers. In this paper, we prove that a hypercube of dimension h admits two edge-disjoint Fibonacci trees of height h, two edge-disjoint Fibonacci trees of height h-2, two edge-disjoint Fibonacci trees of height h-4 and so on, as subgraphs. The result shows that an algorithm with Fibonacci trees as underlying data structure can be implemented concurrently on a hypercube network with no communication latency.

TreeCluster: Massively scalable transmission clustering using phylogenetic trees

OpenAIRE

Moshiri, Alexander

2018-01-01

Background: The ability to infer transmission clusters from molecular data is critical to designing and evaluating viral control strategies. Viral sequencing datasets are growing rapidly, but standard methods of transmission cluster inference do not scale well beyond thousands of sequences. Results: I present TreeCluster, a cross-platform tool that performs transmission cluster inference on a given phylogenetic tree orders of magnitude faster than existing inference methods and supports multi...

Value tree analysis

International Nuclear Information System (INIS)

Keeney, R.; Renn, O.; Winterfeldt, D. von; Kotte, U.

1985-01-01

What are the targets and criteria on which national energy policy should be based. What priorities should be set, and how can different social interests be matched. To answer these questions, a new instrument of decision theory is presented which has been applied with good results to controversial political issues in the USA. The new technique is known under the name of value tree analysis. Members of important West German organisations (BDI, VDI, RWE, the Catholic and Protestant Church, Deutscher Naturschutzring, and ecological research institutions) were asked about the goals of their organisations. These goals were then ordered systematically and arranged in a hierarchical tree structure. The value trees of different groups can be combined into a catalogue of social criteria of acceptability and policy assessment. The authors describe the philosophy and methodology of value tree analysis and give an outline of its application in the development of a socially acceptable energy policy. (orig.) [de

Adjustable chain trees for proteins

DEFF Research Database (Denmark)

Winter, Pawel; Fonseca, Rasmus

2012-01-01

A chain tree is a data structure for changing protein conformations. It enables very fast detection of clashes and free energy potential calculations. A modified version of chain trees that adjust themselves to the changing conformations of folding proteins is introduced. This results in much...... tighter bounding volume hierarchies and therefore fewer intersection checks. Computational results indicate that the efficiency of the adjustable chain trees is significantly improved compared to the traditional chain trees....

Introduction to fault tree analysis

International Nuclear Information System (INIS)

Barlow, R.E.; Lambert, H.E.

1975-01-01

An elementary, engineering oriented introduction to fault tree analysis is presented. The basic concepts, techniques and applications of fault tree analysis, FTA, are described. The two major steps of FTA are identified as (1) the construction of the fault tree and (2) its evaluation. The evaluation of the fault tree can be qualitative or quantitative depending upon the scope, extensiveness and use of the analysis. The advantages, limitations and usefulness of FTA are discussed

Steiner trees in industry

CERN Document Server

Du, Ding-Zhu

2001-01-01

This book is a collection of articles studying various Steiner tree prob­ lems with applications in industries, such as the design of electronic cir­ cuits, computer networking, telecommunication, and perfect phylogeny. The Steiner tree problem was initiated in the Euclidean plane. Given a set of points in the Euclidean plane, the shortest network interconnect­ ing the points in the set is called the Steiner minimum tree. The Steiner minimum tree may contain some vertices which are not the given points. Those vertices are called Steiner points while the given points are called terminals. The shortest network for three terminals was first studied by Fermat (1601-1665). Fermat proposed the problem of finding a point to minimize the total distance from it to three terminals in the Euclidean plane. The direct generalization is to find a point to minimize the total distance from it to n terminals, which is still called the Fermat problem today. The Steiner minimum tree problem is an indirect generalization. Sch...

Water, gravity and trees: Relationship of tree-ring widths and total water storage dynamics

Science.gov (United States)

Creutzfeldt, B.; Heinrich, I.; Merz, B.; Blume, T.; Güntner, A.

2012-04-01

Water stored in the subsurface as groundwater or soil moisture is the main fresh water source not only for drinking water and food production but also for the natural vegetation. In a changing environment water availability becomes a critical issue in many different regions. Long-term observations of the past are needed to improve the understanding of the hydrological system and the prediction of future developments. Tree ring data have repeatedly proved to be valuable sources for reconstructing long-term climate dynamics, e.g. temperature, precipitation and different hydrological variables. In water-limited environments, tree growth is primarily influenced by total water stored in the subsurface and hence, tree-ring records usually contain information about subsurface water storage. The challenge is to retrieve the information on total water storage from tree rings, because a training dataset of water stored in the sub-surface is required for calibration against the tree-ring series. However, measuring water stored in the subsurface is notoriously difficult. We here present high-precision temporal gravimeter measurements which allow for the depth-integrated quantification of total water storage dynamics at the field scale. In this study, we evaluate the relationship of total water storage change and tree ring growth also in the context of the complex interactions of other meteorological forcing factors. A tree-ring chronology was derived from a Norway spruce stand in the Bavarian Forest, Germany. Total water storage dynamics were measured directly by the superconducting gravimeter of the Geodetic Observatory Wettzell for a 9-years period. Time series were extended to 63-years period by a hydrological model using gravity data as the only calibration constrain. Finally, water storage changes were reconstructed based on the relationship between the hydrological model and the tree-ring chronology. Measurement results indicate that tree-ring growth is primarily

The longevity of broadleaf deciduous trees in Northern Hemisphere temperate forests: insights from tree-ring series

Directory of Open Access Journals (Sweden)

Alfredo eDi Filippo

2015-05-01

Full Text Available Understanding the factors controlling the expression of longevity in trees is still an outstanding challenge for tree biologists and forest ecologists. We gathered tree-ring data and literature for broadleaf deciduous (BD temperate trees growing in closed-canopy old-growth forests in the Northern Hemisphere to explore the role of geographic patterns, climate variability, and growth rates on longevity. Our pan-continental analysis, covering 32 species from 12 genera, showed that 300-400 years can be considered a baseline threshold for maximum tree lifespan in many temperate deciduous forests. Maximum age varies greatly in relation to environmental features, even within the same species. Tree longevity is generally promoted by reduced growth rates across large genetic differences and environmental gradients. We argue that slower growth rates, and the associated smaller size, provide trees with an advantage against biotic and abiotic disturbance agents, supporting the idea that size, not age, is the main constraint to tree longevity. The oldest trees were living most of their life in subordinate canopy conditions and/or within primary forests in cool temperate environments and outside major storm tracks. Very old trees are thus characterized by slow growth and often live in forests with harsh site conditions and infrequent disturbance events that kill much of the trees. Temperature inversely controls the expression of longevity in mesophilous species (Fagus spp., but its role in Quercus spp. is more complex and warrants further research in disturbance ecology. Biological, ecological and historical drivers must be considered to understand the constraints imposed to longevity within different forest landscapes.

Up in the tree--the overlooked richness of bryophytes and lichens in tree crowns.

Science.gov (United States)

Boch, Steffen; Müller, Jörg; Prati, Daniel; Blaser, Stefan; Fischer, Markus

2013-01-01

Assessing diversity is among the major tasks in ecology and conservation science. In ecological and conservation studies, epiphytic cryptogams are usually sampled up to accessible heights in forests. Thus, their diversity, especially of canopy specialists, likely is underestimated. If the proportion of those species differs among forest types, plot-based diversity assessments are biased and may result in misleading conservation recommendations. We sampled bryophytes and lichens in 30 forest plots of 20 m × 20 m in three German regions, considering all substrates, and including epiphytic litter fall. First, the sampling of epiphytic species was restricted to the lower 2 m of trees and shrubs. Then, on one representative tree per plot, we additionally recorded epiphytic species in the crown, using tree climbing techniques. Per tree, on average 54% of lichen and 20% of bryophyte species were overlooked if the crown was not been included. After sampling all substrates per plot, including the bark of all shrubs and trees, still 38% of the lichen and 4% of the bryophyte species were overlooked if the tree crown of the sampled tree was not included. The number of overlooked lichen species varied strongly among regions. Furthermore, the number of overlooked bryophyte and lichen species per plot was higher in European beech than in coniferous stands and increased with increasing diameter at breast height of the sampled tree. Thus, our results indicate a bias of comparative studies which might have led to misleading conservation recommendations of plot-based diversity assessments.

Modelling tree biomasses in Finland

Energy Technology Data Exchange (ETDEWEB)

Repola, J.

2013-06-01

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

Geodesic atlas-based labeling of anatomical trees

DEFF Research Database (Denmark)

Feragen, Aasa; Petersen, Jens; Owen, Megan

2015-01-01

We present a fast and robust atlas-based algorithm for labeling airway trees, using geodesic distances in a geometric tree-space. Possible branch label configurations for an unlabeled airway tree are evaluated using distances to a training set of labeled airway trees. In tree-space, airway tree t...... equally complete airway trees, and comparable in performance to that of experts in pulmonary medicine, emphasizing the suitability of the labeling algorithm for clinical use....

Current and potential tree locations in tree line ecotone of Changbai Mountains, Northeast China: the controlling effects of topography.

Science.gov (United States)

Zong, Shengwei; Wu, Zhengfang; Xu, Jiawei; Li, Ming; Gao, Xiaofeng; He, Hongshi; Du, Haibo; Wang, Lei

2014-01-01

Tree line ecotone in the Changbai Mountains has undergone large changes in the past decades. Tree locations show variations on the four sides of the mountains, especially on the northern and western sides, which has not been fully explained. Previous studies attributed such variations to the variations in temperature. However, in this study, we hypothesized that topographic controls were responsible for causing the variations in the tree locations in tree line ecotone of the Changbai Mountains. To test the hypothesis, we used IKONOS images and WorldView-1 image to identify the tree locations and developed a logistic regression model using topographical variables to identify the dominant controls of the tree locations. The results showed that aspect, wetness, and slope were dominant controls for tree locations on western side of the mountains, whereas altitude, SPI, and aspect were the dominant factors on northern side. The upmost altitude a tree can currently reach was 2140 m asl on the northern side and 2060 m asl on western side. The model predicted results showed that habitats above the current tree line on the both sides were available for trees. Tree recruitments under the current tree line may take advantage of the available habitats at higher elevations based on the current tree location. Our research confirmed the controlling effects of topography on the tree locations in the tree line ecotone of Changbai Mountains and suggested that it was essential to assess the tree response to topography in the research of tree line ecotone.

Moose?tree interactions: rebrowsing is common across tree species

OpenAIRE

Mathisen, Karen Marie; Milner, Jos M.; Skarpe, Christina

2017-01-01

Background Plant strategies to resist herbivory include tolerance and avoidance. Tolerance strategies, such as rapid regrowth which increases the palatability of new shoots, can lead to positive feedback loops between plants and herbivores. An example of such a positive feedback occurs when moose (Alces alces) browse trees in boreal forests. We described the degree of change in tree morphology that accumulated over time in response to repeated browsing by moose, using an index of accumulated ...

Mitered fractal trees: constructions and properties

NARCIS (Netherlands)

Verhoeff, T.; Verhoeff, K.; Bosch, R.; McKenna, D.; Sarhangi, R.

2012-01-01

Tree-like structures, that is, branching structures without cycles, are attractive for artful expression. Especially interesting are fractal trees, where each subtree is a scaled and possibly otherwise transformed version of the entire tree. Such trees can be rendered in 3D by using beams with a

Genetic transformation of forest trees

African Journals Online (AJOL)

Admin

In this review, the recent progress on genetic transformation of forest trees were discussed. Its described also, different applications of genetic engineering for improving forest trees or understanding the mechanisms governing genes expression in woody plants. Key words: Genetic transformation, transgenic forest trees, ...

How eco-evolutionary principles can guide tree breeding and tree biotechnology for enhanced productivity.

Science.gov (United States)

Franklin, Oskar; Palmroth, Sari; Näsholm, Torgny

2014-11-01

Tree breeding and biotechnology can enhance forest productivity and help alleviate the rising pressure on forests from climate change and human exploitation. While many physiological processes and genes are targeted in search of genetically improved tree productivity, an overarching principle to guide this search is missing. Here, we propose a method to identify the traits that can be modified to enhance productivity, based on the differences between trees shaped by natural selection and 'improved' trees with traits optimized for productivity. We developed a tractable model of plant growth and survival to explore such potential modifications under a range of environmental conditions, from non-water limited to severely drought-limited sites. We show how key traits are controlled by a trade-off between productivity and survival, and that productivity can be increased at the expense of long-term survival by reducing isohydric behavior (stomatal regulation of leaf water potential) and allocation to defense against pests compared with native trees. In contrast, at dry sites occupied by naturally drought-resistant trees, the model suggests a better strategy may be to select trees with slightly lower wood density than the native trees and to augment isohydric behavior and allocation to defense. Thus, which traits to modify, and in which direction, depend on the original tree species or genotype, the growth environment and wood-quality versus volume production preferences. In contrast to this need for customization of drought and pest resistances, consistent large gains in productivity for all genotypes can be obtained if root traits can be altered to reduce competition for water and nutrients. Our approach illustrates the potential of using eco-evolutionary theory and modeling to guide plant breeding and genetic technology in selecting target traits in the quest for higher forest productivity. © The Author 2014. Published by Oxford University Press. All rights reserved

The K tree score: quantification of differences in the relative branch length and topology of phylogenetic trees.

Science.gov (United States)

Soria-Carrasco, Víctor; Talavera, Gerard; Igea, Javier; Castresana, Jose

2007-11-01

We introduce a new phylogenetic comparison method that measures overall differences in the relative branch length and topology of two phylogenetic trees. To do this, the algorithm first scales one of the trees to have a global divergence as similar as possible to the other tree. Then, the branch length distance, which takes differences in topology and branch lengths into account, is applied to the two trees. We thus obtain the minimum branch length distance or K tree score. Two trees with very different relative branch lengths get a high K score whereas two trees that follow a similar among-lineage rate variation get a low score, regardless of the overall rates in both trees. There are several applications of the K tree score, two of which are explained here in more detail. First, this score allows the evaluation of the performance of phylogenetic algorithms, not only with respect to their topological accuracy, but also with respect to the reproduction of a given branch length variation. In a second example, we show how the K score allows the selection of orthologous genes by choosing those that better follow the overall shape of a given reference tree. http://molevol.ibmb.csic.es/Ktreedist.html

TALL HERB SPRUCE FORESTS AS CLIMAX COMMUNITIES ON LOWLAND SWAMPS OF BRYANSK POLESIE

Directory of Open Access Journals (Sweden)

O. I. Evstigneev

2017-09-01

Full Text Available Nettle grey alder forests are a dominant forest type on lowland swamps in the Bryansk Polesie. They are formed as a result of repeated cuttings in the place of tall herb spruce forests. Tall herb spruce forests are very rare communities in the vegetation cover in this area due to clear cutting, melioration and peat extraction. An assessment of the succession status of tall herb spruce forests and nettle grey alder forests was carried out in this paper. The criteria of climax state and succession state of communities, developed for Eastern European forests, were used. These criteria are based on the degree of intensity of the following signs in the community: 1 the completeness of species composition of tree synusia; 2 the ontogenetic structure of tree species cenopopulation; 3 the gap-mosaic stand structure; 4 the diversity of microsites in soil cover; 5 the completeness of species composition and ecological-coenotic diversity of vascular species. We showed that tall herb spruce forest, as opposed to black alder forest, is close to communities of the climax type. This is evidenced by the following features of cenosis: firstly, all tree species in the area that covers the Bryansk Polesie and that are able to grow on lowland swamps are represented in the spruce forest (Alnus glutinosa, Betula pubescens, Fraxinus excelsior, Padus avium, Picea abies, Salix pentandra, Sorbus aucuparia, Ulmus glabra. Secondly, a steady turnover of generations is carried out in the cenopopulations of main edificators (Picea abies and Alnus glutinosa. This is evidenced by the complete and left-sided structure of their ontogenetic spectrum. Thirdly, a system of asynchronously developing gaps (parcels, which are formed on the site of old tree falls, is formed in the community. This ensures the continuous renewal of spruce and alder populations and creates conditions for the regeneration of other tree species. Fourthly, the structure of biogenic microsites has been formed

Up in the tree--the overlooked richness of bryophytes and lichens in tree crowns.

Directory of Open Access Journals (Sweden)

Steffen Boch

Full Text Available Assessing diversity is among the major tasks in ecology and conservation science. In ecological and conservation studies, epiphytic cryptogams are usually sampled up to accessible heights in forests. Thus, their diversity, especially of canopy specialists, likely is underestimated. If the proportion of those species differs among forest types, plot-based diversity assessments are biased and may result in misleading conservation recommendations. We sampled bryophytes and lichens in 30 forest plots of 20 m × 20 m in three German regions, considering all substrates, and including epiphytic litter fall. First, the sampling of epiphytic species was restricted to the lower 2 m of trees and shrubs. Then, on one representative tree per plot, we additionally recorded epiphytic species in the crown, using tree climbing techniques. Per tree, on average 54% of lichen and 20% of bryophyte species were overlooked if the crown was not been included. After sampling all substrates per plot, including the bark of all shrubs and trees, still 38% of the lichen and 4% of the bryophyte species were overlooked if the tree crown of the sampled tree was not included. The number of overlooked lichen species varied strongly among regions. Furthermore, the number of overlooked bryophyte and lichen species per plot was higher in European beech than in coniferous stands and increased with increasing diameter at breast height of the sampled tree. Thus, our results indicate a bias of comparative studies which might have led to misleading conservation recommendations of plot-based diversity assessments.

Tree Notation: an antifragile program notation

OpenAIRE

Yunits, Breck

2017-01-01

This paper presents Tree Notation, a new simple, universal syntax. Language designers can invent new programming languages, called Tree Languages, on top of Tree Notation. Tree Languages have a number of advantages over traditional programming languages. We include a Visual Abstract to succinctly display the problem and discovery. Then we describe the problem--the BNF to abstract syntax tree (AST) parse step--and introduce the novel solution we discovered: a new family of 2D programming langu...

Tree growth visualization

Science.gov (United States)

L. Linsen; B.J. Karis; E.G. McPherson; B. Hamann

2005-01-01

In computer graphics, models describing the fractal branching structure of trees typically exploit the modularity of tree structures. The models are based on local production rules, which are applied iteratively and simultaneously to create a complex branching system. The objective is to generate three-dimensional scenes of often many realistic- looking and non-...

Individual tree control

Science.gov (United States)

Harvey A. Holt

1989-01-01

Controlling individual unwanted trees in forest stands is a readily accepted method for improving the value of future harvests. The practice is especially important in mixed hardwood forests where species differ considerably in value and within species individual trees differ in quality. Individual stem control is a mechanical or chemical weeding operation that...

Population structure of the ash dieback pathogen, Hymenoscyphus fraxineus, in relation to its mode of arrival in the UK.

Science.gov (United States)

Orton, E S; Brasier, C M; Bilham, L J; Bansal, A; Webber, J F; Brown, J K M

2018-02-01

The ash dieback fungus, Hymenoscyphus fraxineus , a destructive, alien pathogen of common ash ( Fraxinus excelsior ), has spread across Europe over the past 25 years and was first observed in the UK in 2012. To investigate the relationship of the pathogen's population structure to its mode of arrival, isolates were obtained from locations in England and Wales, either where established natural populations of ash had been infected by wind-dispersed ascospores or where the fungus had been introduced on imported planting stock. Population structure was determined by tests for vegetative compatibility (VC), mating type and single-nucleotide polymorphisms (SNPs). VC heterogeneity was high at all locations, with 96% of isolate pairings being incompatible. Frequencies of the MAT1-1-1 and MAT1-2-1 idiomorphs were approximately equal, consistent with H. fraxineus being an obligate outbreeder. Most SNP variation occurred within study location and there was little genetic differentiation between the two types of location in the UK, or between pathogen populations in the UK and continental Europe. There was modest differentiation between UK subpopulations, consistent with genetic variation between source populations in continental Europe. However, there was no evidence of strong founder effects, indicating that numerous individuals of H. fraxineus initiated infection at each location, regardless of the route of pathogen transmission. The ssRNA virus HfMV1 was present at moderate to high frequencies in all UK subpopulations. The results imply that management of an introduced plant pathogen requires action against its spread at the continental level involving coordinated efforts by European countries.

Benthic fauna of extremely acidic lakes (pH 2-3)

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, G G

2001-07-01

The structure of the benthic invertebrate communities were investigated in terms of composition, abundance, and biomass from extremely acidic lakes with pH values from 2 to 3 in areas where coal was intensively mined in the Lusatian region in the eastern region of Germany. Benthic invertebrates colonisation on leaves and the breakdown rate processing of the three deciduous leaf: Betula pendula (birch), Fraxinus excelsior (ash), and Juglans regia (walnut) were investigated. Also, the main key-species of these acidic environments were investigated, in terms of description of pupal exuviae of Chironomus crassimanus and the feeding habit of this acid-resistant species through analysis of their gut content. The benthic food web in extremely acidic mining Lusatian lakes is very short in terms of species richness, trophic relationship, guilds and functional feeding groups. Collector-filters and scraper-grazers were absent in extremely acidic mining lakes (AML 107, AML 111 and AML 117). Shredders as Limnophyes minimus (Diptera, Chironomidae, Orthocladiinae) and Hydrozetes lacustris (Acari, Hydrozetidae) occurred in low abundance in AML 107 and AML 111, and it may be in response to slow leaf breakdown process in these ecosystems, except in AML 117 where the H. lacustris contributed most to ecosystems functioning via the processing of litter. Aquatic insects as Sialis lutaria (Megaloptera, Sialidae), Orectochilus villosus (Coleoptera, Gyrinidae), Coenagrion mercuriale (Odonata, Coenagrionidae), and Phryganeidae (Trichoptera) are the top-predators of these ecosystems. They did not depend on the level of pH in the lakes, but on the availability of food resources. (orig.)

Direct seeding woody species for restoration of bottomlands

Science.gov (United States)

Twedt, D.J.; Connor, Kristina F

2006-01-01

I direct seeded (broadcast) seeds of 39 species of trees and shrubs using an ATV-mounted rotary spreader to initiate restoration of bottomland forest on retired agricultural sites. Four sites were planted during February, 2000, and 13 additional sites were planted during April and May, 2001. After two growing seasons, stem density of direct-seeded species varied greatly among study plots (range = 0 to 888 stems/ha) but averaged only 110 stems/ha. I recommend that future efforts at direct seeding focus on seven shrub species (Amorpha fruticosa L., Cephalanthus occidentalis L., Cornus spp., Crataegus spp., Ilex decidua Walt., Morus rubra L., and Prunus spp.) and seven tree species (Celtis laevigata Willd., Diospyros virginiana L., Fraxinus spp., Gleditsia triacanthos L., Robinia pseudoacacia L., Taxodium distichum (L.) Rich, and Ulmus spp.) that successfully established in these trials.

Using tree diversity to compare phylogenetic heuristics.

Science.gov (United States)

Sul, Seung-Jin; Matthews, Suzanne; Williams, Tiffani L

2009-04-29

Evolutionary trees are family trees that represent the relationships between a group of organisms. Phylogenetic heuristics are used to search stochastically for the best-scoring trees in tree space. Given that better tree scores are believed to be better approximations of the true phylogeny, traditional evaluation techniques have used tree scores to determine the heuristics that find the best scores in the fastest time. We develop new techniques to evaluate phylogenetic heuristics based on both tree scores and topologies to compare Pauprat and Rec-I-DCM3, two popular Maximum Parsimony search algorithms. Our results show that although Pauprat and Rec-I-DCM3 find the trees with the same best scores, topologically these trees are quite different. Furthermore, the Rec-I-DCM3 trees cluster distinctly from the Pauprat trees. In addition to our heatmap visualizations of using parsimony scores and the Robinson-Foulds distance to compare best-scoring trees found by the two heuristics, we also develop entropy-based methods to show the diversity of the trees found. Overall, Pauprat identifies more diverse trees than Rec-I-DCM3. Overall, our work shows that there is value to comparing heuristics beyond the parsimony scores that they find. Pauprat is a slower heuristic than Rec-I-DCM3. However, our work shows that there is tremendous value in using Pauprat to reconstruct trees-especially since it finds identical scoring but topologically distinct trees. Hence, instead of discounting Pauprat, effort should go in improving its implementation. Ultimately, improved performance measures lead to better phylogenetic heuristics and will result in better approximations of the true evolutionary history of the organisms of interest.

Integrating cyber attacks within fault trees

International Nuclear Information System (INIS)

Nai Fovino, Igor; Masera, Marcelo; De Cian, Alessio

2009-01-01

In this paper, a new method for quantitative security risk assessment of complex systems is presented, combining fault-tree analysis, traditionally used in reliability analysis, with the recently introduced Attack-tree analysis, proposed for the study of malicious attack patterns. The combined use of fault trees and attack trees helps the analyst to effectively face the security challenges posed by the introduction of modern ICT technologies in the control systems of critical infrastructures. The proposed approach allows considering the interaction of malicious deliberate acts with random failures. Formal definitions of fault tree and attack tree are provided and a mathematical model for the calculation of system fault probabilities is presented.

Integrating cyber attacks within fault trees

Energy Technology Data Exchange (ETDEWEB)

Nai Fovino, Igor [Joint Research Centre - EC, Institute for the Protection and Security of the Citizen, Ispra, VA (Italy)], E-mail: igor.nai@jrc.it; Masera, Marcelo [Joint Research Centre - EC, Institute for the Protection and Security of the Citizen, Ispra, VA (Italy); De Cian, Alessio [Department of Electrical Engineering, University di Genova, Genoa (Italy)

2009-09-15

In this paper, a new method for quantitative security risk assessment of complex systems is presented, combining fault-tree analysis, traditionally used in reliability analysis, with the recently introduced Attack-tree analysis, proposed for the study of malicious attack patterns. The combined use of fault trees and attack trees helps the analyst to effectively face the security challenges posed by the introduction of modern ICT technologies in the control systems of critical infrastructures. The proposed approach allows considering the interaction of malicious deliberate acts with random failures. Formal definitions of fault tree and attack tree are provided and a mathematical model for the calculation of system fault probabilities is presented.

Tree and shrub expansion over the past 34 years at the tree-line near Abisko, Sweden.

Science.gov (United States)

Rundqvist, Sara; Hedenås, Henrik; Sandström, Anneli; Emanuelsson, Urban; Eriksson, Håkan; Jonasson, Christer; Callaghan, Terry V

2011-09-01

Shrubs and trees are expected to expand in the sub-Arctic due to global warming. Our study was conducted in Abisko, sub-arctic Sweden. We recorded the change in coverage of shrub and tree species over a 32- to 34-year period, in three 50 x 50 m plots; in the alpine-tree-line ecotone. The cover of shrubs and trees (tree stems (> or =3.5 cm) were noted and positions determined. There has been a substantial increase of cover of shrubs and trees, particularly dwarf birch (Betula nana), and mountain birch (Betula pubescens ssp. czerepanovii), and an establishment of aspen (Populus tremula). The other species willows (Salix spp.), juniper (Juniperus communis), and rowan (Sorbus aucuparia) revealed inconsistent changes among the plots. Although this study was unable to identify the causes for the change in shrubs and small trees, they are consistent with anticipated changes due to climate change and reduced herbivory.

DLRS: gene tree evolution in light of a species tree.

Science.gov (United States)

Sjöstrand, Joel; Sennblad, Bengt; Arvestad, Lars; Lagergren, Jens

2012-11-15

PrIME-DLRS (or colloquially: 'Delirious') is a phylogenetic software tool to simultaneously infer and reconcile a gene tree given a species tree. It accounts for duplication and loss events, a relaxed molecular clock and is intended for the study of homologous gene families, for example in a comparative genomics setting involving multiple species. PrIME-DLRS uses a Bayesian MCMC framework, where the input is a known species tree with divergence times and a multiple sequence alignment, and the output is a posterior distribution over gene trees and model parameters. PrIME-DLRS is available for Java SE 6+ under the New BSD License, and JAR files and source code can be downloaded from http://code.google.com/p/jprime/. There is also a slightly older C++ version available as a binary package for Ubuntu, with download instructions at http://prime.sbc.su.se. The C++ source code is available upon request. joel.sjostrand@scilifelab.se or jens.lagergren@scilifelab.se. PrIME-DLRS is based on a sound probabilistic model (Åkerborg et al., 2009) and has been thoroughly validated on synthetic and biological datasets (Supplementary Material online).

Tree Species Richness Promotes Invertebrate Herbivory on Congeneric Native and Exotic Tree Saplings in a Young Diversity Experiment.

Directory of Open Access Journals (Sweden)

Annika Wein

Full Text Available Tree diversity in forests is an important driver of ecological processes including herbivory. Empirical evidence suggests both negative and positive effects of tree diversity on herbivory, which can be, respectively, attributed to associational resistance or associational susceptibility. Tree diversity experiments allow testing for associational effects, but evidence regarding which pattern predominates is mixed. Furthermore, it is unknown if herbivory on tree species of native vs. exotic origin is influenced by changing tree diversity in a similar way, or if exotic tree species escape natural enemies, resulting in lower damage that is unrelated to tree diversity. To address these questions, we established a young tree diversity experiment in temperate southwestern Germany that uses high planting density (49 trees per plot; plot size 13 m2. The species pool consists of six congeneric species pairs of European and North American origin (12 species in total planted in monocultures and mixtures (1, 2, 4, 6 species. We assessed leaf damage by leaf-chewing insects on more than 5,000 saplings of six broadleaved tree species. Plot-level tree species richness increased leaf damage, which more than doubled from monocultures to six-species mixtures, strongly supporting associational susceptibility. However, leaf damage among congeneric native and exotic species pairs was similar. There were marked differences in patterns of leaf damage across tree genera, and only the genera likely having a predominately generalist herbivore community showed associational susceptibility, irrespective of the geographical origin of a tree species. In conclusion, an increase in tree species richness in young temperate forests may result in associational susceptibility to feeding by generalist herbivores.

Establishment in treeshelter. II. Effect of shelter color on gas exchange and hardiness

International Nuclear Information System (INIS)

Kjelgren, R.; Montague, D.T.; Rupp, L.A.

1997-01-01

We investigated the microclimate, gas exchange, and growth of feild-grown Norway maple (Acerplatanoides L.) and green ash (Fraxinus pennsylvanica Marsh) trees nonsheltered, and in brown and white shelters. Shelter microclimate-air temperature (Ta), vapor pressure deficit (VPD), and radiation -and tree leaf area, growth in diameter, stomatal conductance (gs), and photosynthesis were measured during the first growing season after bare-root transplanting. Bark temperatures in midwinter were also measured. Treeshelter microclimate was greenhouse-like compared to ambient conditions, as shortwave radiation was lower, and midday Ta and relative humidity were higher. Although trees in shelters had greater shoot elongation and higher gs than trees grown without shelters, photosynthesis was not different. White shelters allowed 25% more shortwave radiation penetration and increased Ta by 2 to 4 degrees C and VPD by 0.5-1 kPa over brown shelters. However, tree growth and gas exchange generally were not affected by shelter color. Winter injury was increased for trees in shelters and varied with species and shelter color. Both species exhibited shoot dieback in shelters the spring following a winter where bark temperatures varied 40 to 50 degrees C diurnally. More new growth died on maple, particularly in white shelters where several trees were killed. These data suggest that supra optimal summer and winter temperatures may reduce vigor and interfere with cold tolerance of some species grown in shelters

Effects of tree-to-tree variations on sap flux-based transpiration estimates in a forested watershed

Science.gov (United States)

Kume, Tomonori; Tsuruta, Kenji; Komatsu, Hikaru; Kumagai, Tomo'omi; Higashi, Naoko; Shinohara, Yoshinori; Otsuki, Kyoichi

2010-05-01

To estimate forest stand-scale water use, we assessed how sample sizes affect confidence of stand-scale transpiration (E) estimates calculated from sap flux (Fd) and sapwood area (AS_tree) measurements of individual trees. In a Japanese cypress plantation, we measured Fd and AS_tree in all trees (n = 58) within a 20 × 20 m study plot, which was divided into four 10 × 10 subplots. We calculated E from stand AS_tree (AS_stand) and mean stand Fd (JS) values. Using Monte Carlo analyses, we examined potential errors associated with sample sizes in E, AS_stand, and JS by using the original AS_tree and Fd data sets. Consequently, we defined optimal sample sizes of 10 and 15 for AS_stand and JS estimates, respectively, in the 20 × 20 m plot. Sample sizes greater than the optimal sample sizes did not decrease potential errors. The optimal sample sizes for JS changed according to plot size (e.g., 10 × 10 m and 10 × 20 m), while the optimal sample sizes for AS_stand did not. As well, the optimal sample sizes for JS did not change in different vapor pressure deficit conditions. In terms of E estimates, these results suggest that the tree-to-tree variations in Fd vary among different plots, and that plot size to capture tree-to-tree variations in Fd is an important factor. This study also discusses planning balanced sampling designs to extrapolate stand-scale estimates to catchment-scale estimates.

Tests with VHR images for the identification of olive trees and other fruit trees in the European Union

Science.gov (United States)

Masson, Josiane; Soille, Pierre; Mueller, Rick

2004-10-01

In the context of the Common Agricultural Policy (CAP) there is a strong interest of the European Commission for counting and individually locating fruit trees. An automatic counting algorithm developed by the JRC (OLICOUNT) was used in the past for olive trees only, on 1m black and white orthophotos but with limits in case of young trees or irregular groves. This study investigates the improvement of fruit tree identification using VHR images on a large set of data in three test sites, one in Creta (Greece; one in the south-east of France with a majority of olive trees and associated fruit trees, and the last one in Florida on citrus trees. OLICOUNT was compared with two other automatic tree counting, applications, one using the CRISP software on citrus trees and the other completely automatic based on regional minima (morphological image analysis). Additional investigation was undertaken to refine the methods. This paper describes the automatic methods and presents the results derived from the tests.

The Hopi Fruit Tree Book.

Science.gov (United States)

Nyhuis, Jane

Referring as often as possible to traditional Hopi practices and to materials readily available on the reservation, the illustrated booklet provides information on the care and maintenance of young fruit trees. An introduction to fruit trees explains the special characteristics of new trees, e.g., grafting, planting pits, and watering. The…

Rectilinear Full Steiner Tree Generation

DEFF Research Database (Denmark)

Zachariasen, Martin

1999-01-01

The fastest exact algorithm (in practice) for the rectilinear Steiner tree problem in the plane uses a two-phase scheme: First, a small but sufficient set of full Steiner trees (FSTs) is generated and then a Steiner minimum tree is constructed from this set by using simple backtrack search, dynamic...

Reconciliation with non-binary species trees.

Science.gov (United States)

Vernot, Benjamin; Stolzer, Maureen; Goldman, Aiton; Durand, Dannie

2008-10-01

Reconciliation extracts information from the topological incongruence between gene and species trees to infer duplications and losses in the history of a gene family. The inferred duplication-loss histories provide valuable information for a broad range of biological applications, including ortholog identification, estimating gene duplication times, and rooting and correcting gene trees. While reconciliation for binary trees is a tractable and well studied problem, there are no algorithms for reconciliation with non-binary species trees. Yet a striking proportion of species trees are non-binary. For example, 64% of branch points in the NCBI taxonomy have three or more children. When applied to non-binary species trees, current algorithms overestimate the number of duplications because they cannot distinguish between duplication and incomplete lineage sorting. We present the first algorithms for reconciling binary gene trees with non-binary species trees under a duplication-loss parsimony model. Our algorithms utilize an efficient mapping from gene to species trees to infer the minimum number of duplications in O(|V(G) | x (k(S) + h(S))) time, where |V(G)| is the number of nodes in the gene tree, h(S) is the height of the species tree and k(S) is the size of its largest polytomy. We present a dynamic programming algorithm which also minimizes the total number of losses. Although this algorithm is exponential in the size of the largest polytomy, it performs well in practice for polytomies with outdegree of 12 or less. We also present a heuristic which estimates the minimal number of losses in polynomial time. In empirical tests, this algorithm finds an optimal loss history 99% of the time. Our algorithms have been implemented in NOTUNG, a robust, production quality, tree-fitting program, which provides a graphical user interface for exploratory analysis and also supports automated, high-throughput analysis of large data sets.

Heterogeneous Compression of Large Collections of Evolutionary Trees.

Science.gov (United States)

Matthews, Suzanne J

2015-01-01

Compressing heterogeneous collections of trees is an open problem in computational phylogenetics. In a heterogeneous tree collection, each tree can contain a unique set of taxa. An ideal compression method would allow for the efficient archival of large tree collections and enable scientists to identify common evolutionary relationships over disparate analyses. In this paper, we extend TreeZip to compress heterogeneous collections of trees. TreeZip is the most efficient algorithm for compressing homogeneous tree collections. To the best of our knowledge, no other domain-based compression algorithm exists for large heterogeneous tree collections or enable their rapid analysis. Our experimental results indicate that TreeZip averages 89.03 percent (72.69 percent) space savings on unweighted (weighted) collections of trees when the level of heterogeneity in a collection is moderate. The organization of the TRZ file allows for efficient computations over heterogeneous data. For example, consensus trees can be computed in mere seconds. Lastly, combining the TreeZip compressed (TRZ) file with general-purpose compression yields average space savings of 97.34 percent (81.43 percent) on unweighted (weighted) collections of trees. Our results lead us to believe that TreeZip will prove invaluable in the efficient archival of tree collections, and enables scientists to develop novel methods for relating heterogeneous collections of trees.

Fault tree graphics

International Nuclear Information System (INIS)

Bass, L.; Wynholds, H.W.; Porterfield, W.R.

1975-01-01

Described is an operational system that enables the user, through an intelligent graphics terminal, to construct, modify, analyze, and store fault trees. With this system, complex engineering designs can be analyzed. This paper discusses the system and its capabilities. Included is a brief discussion of fault tree analysis, which represents an aspect of reliability and safety modeling

Environmental Fate of Emamectin Benzoate After Tree Micro Injection of Horse Chestnut Trees

OpenAIRE

Burkhard, Rene; Binz, Heinz; Roux, Christian A; Brunner, Matthias; Ruesch, Othmar; Wyss, Peter

2014-01-01

Emamectin benzoate, an insecticide derived from the avermectin family of natural products, has a unique translocation behavior in trees when applied by tree micro injection (TMI), which can result in protection from insect pests (foliar and borers) for several years. Active ingredient imported into leaves was measured at the end of season in the fallen leaves of treated horse chestnut (Aesculus hippocastanum) trees. The dissipation of emamectin benzoate in these leaves seems to be biphasic an...

Factors that influence Christmas tree sales

Science.gov (United States)

Thomas H. Pendleton; Lawrence D. Garrett

1970-01-01

An analysis of the metropolitan Christmas tree market in Winston-Salem, N. C., shows that to sell more trees, Christmas tree retailers should locate their lots on heavily traveled streets in business areas, have adequate parking facilities, advertise, and have attractive displays of trees. Retailers who follow these practices can expect to receive higher prices for...

The View from the Trees: Nocturnal Bull Ants, Myrmecia midas, Use the Surrounding Panorama While Descending from Trees.

Science.gov (United States)

Freas, Cody A; Wystrach, Antione; Narendra, Ajay; Cheng, Ken

2018-01-01

Solitary foraging ants commonly use visual cues from their environment for navigation. Foragers are known to store visual scenes from the surrounding panorama for later guidance to known resources and to return successfully back to the nest. Several ant species travel not only on the ground, but also climb trees to locate resources. The navigational information that guides animals back home during their descent, while their body is perpendicular to the ground, is largely unknown. Here, we investigate in a nocturnal ant, Myrmecia midas , whether foragers travelling down a tree use visual information to return home. These ants establish nests at the base of a tree on which they forage and in addition, they also forage on nearby trees. We collected foragers and placed them on the trunk of the nest tree or a foraging tree in multiple compass directions. Regardless of the displacement location, upon release ants immediately moved to the side of the trunk facing the nest during their descent. When ants were released on non-foraging trees near the nest, displaced foragers again travelled around the tree to the side facing the nest. All the displaced foragers reached the correct side of the tree well before reaching the ground. However, when the terrestrial cues around the tree were blocked, foragers were unable to orient correctly, suggesting that the surrounding panorama is critical to successful orientation on the tree. Through analysis of panoramic pictures, we show that views acquired at the base of the foraging tree nest can provide reliable nest-ward orientation up to 1.75 m above the ground. We discuss, how animals descending from trees compare their current scene to a memorised scene and report on the similarities in visually guided behaviour while navigating on the ground and descending from trees.

The View from the Trees: Nocturnal Bull Ants, Myrmecia midas, Use the Surrounding Panorama While Descending from Trees

Directory of Open Access Journals (Sweden)

Cody A. Freas

2018-01-01

Full Text Available Solitary foraging ants commonly use visual cues from their environment for navigation. Foragers are known to store visual scenes from the surrounding panorama for later guidance to known resources and to return successfully back to the nest. Several ant species travel not only on the ground, but also climb trees to locate resources. The navigational information that guides animals back home during their descent, while their body is perpendicular to the ground, is largely unknown. Here, we investigate in a nocturnal ant, Myrmecia midas, whether foragers travelling down a tree use visual information to return home. These ants establish nests at the base of a tree on which they forage and in addition, they also forage on nearby trees. We collected foragers and placed them on the trunk of the nest tree or a foraging tree in multiple compass directions. Regardless of the displacement location, upon release ants immediately moved to the side of the trunk facing the nest during their descent. When ants were released on non-foraging trees near the nest, displaced foragers again travelled around the tree to the side facing the nest. All the displaced foragers reached the correct side of the tree well before reaching the ground. However, when the terrestrial cues around the tree were blocked, foragers were unable to orient correctly, suggesting that the surrounding panorama is critical to successful orientation on the tree. Through analysis of panoramic pictures, we show that views acquired at the base of the foraging tree nest can provide reliable nest-ward orientation up to 1.75 m above the ground. We discuss, how animals descending from trees compare their current scene to a memorised scene and report on the similarities in visually guided behaviour while navigating on the ground and descending from trees.

Encoding phylogenetic trees in terms of weighted quartets.

Science.gov (United States)

Grünewald, Stefan; Huber, Katharina T; Moulton, Vincent; Semple, Charles

2008-04-01

One of the main problems in phylogenetics is to develop systematic methods for constructing evolutionary or phylogenetic trees. For a set of species X, an edge-weighted phylogenetic X-tree or phylogenetic tree is a (graph theoretical) tree with leaf set X and no degree 2 vertices, together with a map assigning a non-negative length to each edge of the tree. Within phylogenetics, several methods have been proposed for constructing such trees that work by trying to piece together quartet trees on X, i.e. phylogenetic trees each having four leaves in X. Hence, it is of interest to characterise when a collection of quartet trees corresponds to a (unique) phylogenetic tree. Recently, Dress and Erdös provided such a characterisation for binary phylogenetic trees, that is, phylogenetic trees all of whose internal vertices have degree 3. Here we provide a new characterisation for arbitrary phylogenetic trees.

Microwave sensing of tree trunks

Science.gov (United States)

Jezova, Jana; Mertens, Laurence; Lambot, Sebastien

2015-04-01

The main subject of this research is the observation of the inner part of living tree trunks using ground-penetrating radar (GPR). Trees are everyday part of human life and therefore it is important to pay attention to the tree conditions. The most obvious consequence of the poor tree condition is dead or injury caused by falling tree. The trunk internal structure is divided into three main parts: heartwood, sapwood and bark, which make this medium highly anisotropic and heterogeneous. Furthermore, the properties of the wood are not only specie-dependent but also depend on genetic and on environmental conditions. In urban areas the main problem for the stability of the trees relies in the apparition of decays provoked by fungi, insect or birds. This results in cavities or decreasing of the support capacity of the tree. GPR has proved itself to be a very powerful electromagnetic tool for non-destructive detection of buried objects. Since the beginning of the 20th century it has been used in several different areas (archaeology, landmine detection, civil engineering, ...). GPR uses the principle of the scattering of the electromagnetic waves that are radiated from a transmitting antenna. Then the waves propagate through the medium and are reflected from the object and then they are received by a receiving antenna. The velocity of the scattered signal is determined primarily by the permittivity of the material. The optimal functionality of the GPR was investigated using the numerical simulation tool gprMax2D. This tool is based on a Finite-Difference Time-Domain (FDTD) numerical model. Subsequently, the GPR functionality was tested using the laboratory model of a decayed tree trunk. Afterwards, the results and lessons learnt in the simplified tests will be used in the processing of the real data and will help to achieve deeper understanding of them. The laboratory model of the tree trunk was made by plastic or carton pipes and filled by sand. Space inside the model

TREE2FASTA: a flexible Perl script for batch extraction of FASTA sequences from exploratory phylogenetic trees.

Science.gov (United States)

Sauvage, Thomas; Plouviez, Sophie; Schmidt, William E; Fredericq, Suzanne

2018-03-05

The body of DNA sequence data lacking taxonomically informative sequence headers is rapidly growing in user and public databases (e.g. sequences lacking identification and contaminants). In the context of systematics studies, sorting such sequence data for taxonomic curation and/or molecular diversity characterization (e.g. crypticism) often requires the building of exploratory phylogenetic trees with reference taxa. The subsequent step of segregating DNA sequences of interest based on observed topological relationships can represent a challenging task, especially for large datasets. We have written TREE2FASTA, a Perl script that enables and expedites the sorting of FASTA-formatted sequence data from exploratory phylogenetic trees. TREE2FASTA takes advantage of the interactive, rapid point-and-click color selection and/or annotations of tree leaves in the popular Java tree-viewer FigTree to segregate groups of FASTA sequences of interest to separate files. TREE2FASTA allows for both simple and nested segregation designs to facilitate the simultaneous preparation of multiple data sets that may overlap in sequence content.

Public Reactions to New Street Tree Planting

Directory of Open Access Journals (Sweden)

Ruth A. Rae

2010-01-01

Full Text Available MillionTreesNYC, which has the goal of planting one million trees in New York City by 2017, is intended to make New York City a greener, more sustainable city and is part of the Mayor’s comprehensive long term strategic plan, PlaNYC. Through planting a tree at every suitable sidewalk location in the city, the City of New York is transforming blocks and communities, and providing a variety of environmental, social and aesthetic benefits. This article examines the large scale municipal planting of new street trees and the reaction by some of the pubic to this planting.Trees offer benefits to the city overall, but the public may not understand these benefits or the street tree planting process. Between 2007 and 2009, the Department of Parks & Recreation planted 53,235 new street trees, and received 4,108 items of correspondence from the public. The majority of this correspondence consisted of public comments about the City’s new street tree planting policies and processes including placement objections, maintenance concerns, reports of resultant damage from tree planting operations, requests for new street trees and reports of tree conditions.This study describes the operational policies that guide New York City's municipal street tree planting, and results of content and spatial analysis of the correspondence. Qualitative analysis of the correspondence revealed the public perceptions and concerns related to the MillionTreesNYC program. Spatial analysis explored the relationship between the planting locations of new street trees and the locations of the citizen correspondence.Public reactions to this large scale municipal planting are related to the dual public and private nature of the sidewalk, issues of territoriality, responsibility, aesthetics and place attachment. Correspondence volume was associated with the scale of the new street tree block planting program, and the effectiveness of NYC’s 311 Customer Service Center. The discussion

Generic physical protection logic trees

International Nuclear Information System (INIS)

Paulus, W.K.

1981-10-01

Generic physical protection logic trees, designed for application to nuclear facilities and materials, are presented together with a method of qualitative evaluation of the trees for design and analysis of physical protection systems. One or more defense zones are defined where adversaries interact with the physical protection system. Logic trees that are needed to describe the possible scenarios within a defense zone are selected. Elements of a postulated or existing physical protection system are tagged to the primary events of the logic tree. The likelihood of adversary success in overcoming these elements is evaluated on a binary, yes/no basis. The effect of these evaluations is propagated through the logic of each tree to determine whether the adversary is likely to accomplish the end event of the tree. The physical protection system must be highly likely to overcome the adversary before he accomplishes his objective. The evaluation must be conducted for all significant states of the site. Deficiencies uncovered become inputs to redesign and further analysis, closing the loop on the design/analysis cycle

Generic physical protection logic trees

Energy Technology Data Exchange (ETDEWEB)

Paulus, W.K.

1981-10-01

Generic physical protection logic trees, designed for application to nuclear facilities and materials, are presented together with a method of qualitative evaluation of the trees for design and analysis of physical protection systems. One or more defense zones are defined where adversaries interact with the physical protection system. Logic trees that are needed to describe the possible scenarios within a defense zone are selected. Elements of a postulated or existing physical protection system are tagged to the primary events of the logic tree. The likelihood of adversary success in overcoming these elements is evaluated on a binary, yes/no basis. The effect of these evaluations is propagated through the logic of each tree to determine whether the adversary is likely to accomplish the end event of the tree. The physical protection system must be highly likely to overcome the adversary before he accomplishes his objective. The evaluation must be conducted for all significant states of the site. Deficiencies uncovered become inputs to redesign and further analysis, closing the loop on the design/analysis cycle.

Tree-Based Unrooted Phylogenetic Networks.

Science.gov (United States)

Francis, A; Huber, K T; Moulton, V

2018-02-01

Phylogenetic networks are a generalization of phylogenetic trees that are used to represent non-tree-like evolutionary histories that arise in organisms such as plants and bacteria, or uncertainty in evolutionary histories. An unrooted phylogenetic network on a non-empty, finite set X of taxa, or network, is a connected, simple graph in which every vertex has degree 1 or 3 and whose leaf set is X. It is called a phylogenetic tree if the underlying graph is a tree. In this paper we consider properties of tree-based networks, that is, networks that can be constructed by adding edges into a phylogenetic tree. We show that although they have some properties in common with their rooted analogues which have recently drawn much attention in the literature, they have some striking differences in terms of both their structural and computational properties. We expect that our results could eventually have applications to, for example, detecting horizontal gene transfer or hybridization which are important factors in the evolution of many organisms.

Improved prediction of hardwood tree biomass derived from wood density estimates and form factors for whole trees

Science.gov (United States)

David W. MacFarlane; Neil R. Ver Planck

2012-01-01

Data from hardwood trees in Michigan were analyzed to investigate how differences in whole-tree form and wood density between trees of different stem diameter relate to residual error in standard-type biomass equations. The results suggested that whole-tree wood density, measured at breast height, explained a significant proportion of residual error in standard-type...

Wood density variation and tree ring distinctness in Gmelina arborea trees by x-ray densitometry

Directory of Open Access Journals (Sweden)

Roger Moya

2009-03-01

Full Text Available Due to its relationship with other properties, wood density is the main wood quality parameter. Modern, accuratemethods such as X-ray densitometry - are applied to determine the spatial distribution of density in wood sections and to evaluatewood quality. The objectives of this study were to determinate the influence of growing conditions on wood density variation andtree ring demarcation of gmelina trees from fast growing plantations in Costa Rica. The wood density was determined by X-raydensitometry method. Wood samples were cut from gmelina trees and were exposed to low X-rays. The radiographic films weredeveloped and scanned using a 256 gray scale with 1000 dpi resolution and the wood density was determined by CRAD and CERDsoftware. The results showed tree-ring boundaries were distinctly delimited in trees growing in site with rainfall lower than 2510 mm/year. It was demonstrated that tree age, climatic conditions and management of plantation affects wood density and its variability. Thespecific effect of variables on wood density was quantified by for multiple regression method. It was determined that tree yearexplained 25.8% of the total variation of density and 19.9% were caused by climatic condition where the tree growing. Wood densitywas less affected by the intensity of forest management with 5.9% of total variation.

Autumn frost hardiness in Norway spruce plus tree progeny and trees of the local and transferred provenances in central Sweden.

Science.gov (United States)

Hannerz, Mats; Westin, Johan

2005-09-01

Reforestation with provenances from locations remote from the planting site (transferred provenances) or the progeny of trees of local provenances selected for superior form and vigor (plus trees) offer alternative means to increase yield over that obtained by the use of seed from unselected trees of the local provenance. Under Swedish conditions, Norway spruce (Picea abies (L.) Karst.) of certain transferred provenances generally has an advantage in productivity relative to the local provenance comparable to that of progeny of plus trees. The aim of this study was to explore the extent to which productivity gains achieved by provenance transfer or the use of plus tree progeny are associated with reductions in autumn frost hardiness, relative to that of trees of the local provenance. In a field trial with 19-year-old trees in central Sweden, bud hardiness was tested on four occasions during the autumn of 2002. Trees of the local provenance were compared with trees of a south Swedish provenance originating 3 degrees of latitude to the south, a Belarusian provenance and the progeny of plus trees of local origin. The Belarusian provenance was the least hardy and the local provenance the most hardy, with plus tree progeny and the south Swedish provenance being intermediate in hardiness. Both the Belarusian provenance and the plus tree progeny were significantly taller than trees of the other populations. Within provenances, tree height was negatively correlated with autumn frost hardiness. Among the plus tree progeny, however, no such correlation between tree height and autumn frost hardiness was found. It is concluded that although the gain in productivity achieved by provenance transfer from Belarus was comparable to that achieved by using the progeny of plus trees of the local provenance, the use of trees of the Belarus provenance involved an increased risk of autumn frost damage because of later hardening.

Inferences from growing trees backwards

Science.gov (United States)

David W. Green; Kent A. McDonald

1997-01-01

The objective of this paper is to illustrate how longitudinal stress wave techniques can be useful in tracking the future quality of a growing tree. Monitoring the quality of selected trees in a plantation forest could provide early input to decisions on the effectiveness of management practices, or future utilization options, for trees in a plantation. There will...

The stopping rules for winsorized tree

Science.gov (United States)

Ch'ng, Chee Keong; Mahat, Nor Idayu

2017-11-01

Winsorized tree is a modified tree-based classifier that is able to investigate and to handle all outliers in all nodes along the process of constructing the tree. It overcomes the tedious process of constructing a classical tree where the splitting of branches and pruning go concurrently so that the constructed tree would not grow bushy. This mechanism is controlled by the proposed algorithm. In winsorized tree, data are screened for identifying outlier. If outlier is detected, the value is neutralized using winsorize approach. Both outlier identification and value neutralization are executed recursively in every node until predetermined stopping criterion is met. The aim of this paper is to search for significant stopping criterion to stop the tree from further splitting before overfitting. The result obtained from the conducted experiment on pima indian dataset proved that the node could produce the final successor nodes (leaves) when it has achieved the range of 70% in information gain.

Meta-learning in decision tree induction

CERN Document Server

Grąbczewski, Krzysztof

2014-01-01

The book focuses on different variants of decision tree induction but also describes  the meta-learning approach in general which is applicable to other types of machine learning algorithms. The book discusses different variants of decision tree induction and represents a useful source of information to readers wishing to review some of the techniques used in decision tree learning, as well as different ensemble methods that involve decision trees. It is shown that the knowledge of different components used within decision tree learning needs to be systematized to enable the system to generate and evaluate different variants of machine learning algorithms with the aim of identifying the top-most performers or potentially the best one. A unified view of decision tree learning enables to emulate different decision tree algorithms simply by setting certain parameters. As meta-learning requires running many different processes with the aim of obtaining performance results, a detailed description of the experimen...

Forest Health Management and Detection of Invasive Forest Insects

Directory of Open Access Journals (Sweden)

Kaelyn Finley

2016-05-01

Full Text Available The objectives of this review paper are to provide an overview of issues related to forest health and forest entomology, explain existing methods for forest insect pest detection, and provide background information on a case study of emerald ash borer. Early detection of potentially invasive insect species is a key aspect of preventing these species from causing damage. Invasion management efforts are typically more feasible and efficient if they are applied as early as possible. Two proposed approaches for detection are highlighted and include dendroentomology and near infrared spectroscopy (NIR. Dendroentomology utilizes tree ring principles to identify the years of outbreak and the dynamics of past insect herbivory on trees. NIR has been successfully used for assessing various forest health concerns (primarily hyperspectral imaging and decay in trees. Emerald ash borer (EAB (Agrilus planipennis, is a non-native beetle responsible for widespread mortality of several North American ash species (Fraxinus sp.. Current non-destructive methods for early detection of EAB in specific trees are limited, which restricts the effectiveness of management efforts. Ongoing research efforts are focused on developing methods for early detection of emerald ash borer.

Generic Ising trees

DEFF Research Database (Denmark)

Durhuus, Bergfinnur Jøgvan; Napolitano, George Maria

2012-01-01

The Ising model on a class of infinite random trees is defined as a thermodynamiclimit of finite systems. A detailed description of the corresponding distribution of infinite spin configurations is given. As an application, we study the magnetization properties of such systems and prove that they......The Ising model on a class of infinite random trees is defined as a thermodynamiclimit of finite systems. A detailed description of the corresponding distribution of infinite spin configurations is given. As an application, we study the magnetization properties of such systems and prove...... that they exhibit no spontaneous magnetization. Furthermore, the values of the Hausdorff and spectral dimensions of the underlying trees are calculated and found to be, respectively,¯dh =2 and¯ds = 4/3....

Phylogenetic trees and Euclidean embeddings.

Science.gov (United States)

Layer, Mark; Rhodes, John A

2017-01-01

It was recently observed by de Vienne et al. (Syst Biol 60(6):826-832, 2011) that a simple square root transformation of distances between taxa on a phylogenetic tree allowed for an embedding of the taxa into Euclidean space. While the justification for this was based on a diffusion model of continuous character evolution along the tree, here we give a direct and elementary explanation for it that provides substantial additional insight. We use this embedding to reinterpret the differences between the NJ and BIONJ tree building algorithms, providing one illustration of how this embedding reflects tree structures in data.

Tritium concentrations in tree ring cellulose

International Nuclear Information System (INIS)

Kaji, Toshio; Momoshima, Noriyuki; Takashima, Yoshimasa.

1989-01-01

Measurements of tritium (tissue bound tritium; TBT) concentration in tree rings are presented and discussed. Such measurement is expected to provide a useful means of estimating the tritium level in the environment in the past. The concentration of tritium bound in the tissue (TBT) in a tree ring considered to reflect the environmental tritium level in the area at the time of the formation of the ring, while the concentration of tritium in the free water in the tissue represents the current environmental tritium level. First, tritium concentration in tree ring cellulose sampled from a cedar tree grown in a typical environment in Fukuoka Prefecture is compared with the tritium concentration in precipitation in Tokyo. Results show that the year-to-year variations in the tritium concentration in the tree rings agree well with those in precipitation. The maximum concentration, which occurred in 1963, is attibuted to atmospheric nuclear testing which was performed frequently during the 1961 - 1963 period. Measurement is also made of the tritium concentration in tree ring cellulose sampled from a pine tree grown near the Isotope Center of Kyushu University (Fukuoka). Results indicate that the background level is higher probably due to the release of tritium from the facilities around the pine tree. Thus, measurement of tritium in tree ring cellulose clearly shows the year-to-year variation in the tritium concentration in the atmosphere. (N.K.)

Totally optimal decision trees for Boolean functions

KAUST Repository

Chikalov, Igor

2016-07-28

We study decision trees which are totally optimal relative to different sets of complexity parameters for Boolean functions. A totally optimal tree is an optimal tree relative to each parameter from the set simultaneously. We consider the parameters characterizing both time (in the worst- and average-case) and space complexity of decision trees, i.e., depth, total path length (average depth), and number of nodes. We have created tools based on extensions of dynamic programming to study totally optimal trees. These tools are applicable to both exact and approximate decision trees, and allow us to make multi-stage optimization of decision trees relative to different parameters and to count the number of optimal trees. Based on the experimental results we have formulated the following hypotheses (and subsequently proved): for almost all Boolean functions there exist totally optimal decision trees (i) relative to the depth and number of nodes, and (ii) relative to the depth and average depth.

Trees for future forests

DEFF Research Database (Denmark)

Lobo, Albin

Climate change creates new challenges in forest management. The increase in temperature may in the long run be beneficial for the forests in the northern latitudes, but the high rate at which climate change is predicted to proceed will make adaptation difficult because trees are long living sessile...... organisms. The aim of the present thesis is therefore to explore genetic resilience and phenotypic plasticity mechanisms that allows trees to adapt and evolve with changing climates. The thesis focus on the abiotic factors associated with climate change, especially raised temperatures and lack...... age of these tree species and the uncertainty around the pace and effect of climate, it remains an open question if the native populations can respond fast enough. Phenotypic plasticity through epigenetic regulation of spring phenology is found to be present in a tree species which might act...