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Sample records for blue oak quercus

  1. Effects of fire on naturally occurring blue oak (Quercus douglasii) saplings

    Science.gov (United States)

    Tedmund J. Swiecki; Elizabeth Bernhardt

    2002-01-01

    We studied the survival and regrowth of naturally-occurring blue oak saplings burned in a September 1996 arson fire in Vacaville, California. The saplings (pre-fire height 33-353 cm) were burned in a rapid, low-moderate intensity fire. Of 67 blue oak saplings surveyed, 4 failed to resprout after the fire and 2 more died within the following 5 years (9 percent mortality...

  2. Microhabitat and Environmental Relationships of Bryophytes in Blue Oak (Quercus douglasii H. & A.) Woodlands and Forests of Central Coastal California

    Science.gov (United States)

    Mark Borchert; Daniel Norris

    1991-01-01

    Microhabitat preferences and species-environment patterns were quantified for bryophytes in blue oak woodlands and forests of central coastal California. Presence data for mosses collected from 149 400 m2 plots were analyzed using canonical correspondence analysis (CCA), a multivariate direct gradient analysis technique. Separate ordinations were performed for...

  3. Effects of fire and browsing on regeneration of blue oak

    Science.gov (United States)

    James W. Bartolome; Mitchel P. McClaran; Barbara H. Allen-Diaz; Jim Dunne; Lawrence D. Ford; Richard B. Standiford; Neil K. McDougald; Larry C. Forero

    2002-01-01

    Blue oaks (Quercus douglasii) are not regenerating well over much of California. The roles of fire and browsing in regeneration are probably significant, but poorly understood. We burned two foothill blue oak woodland sites which contained significant numbers of small trees between 40 and 70 cm tall, then compared height growth over 14 years among 48...

  4. Blue Oak Canopy Effect on Seasonal Forage Production and Quality

    Science.gov (United States)

    William E. Frost; Neil K. McDougald; Montague W. Demment

    1991-01-01

    Forage production and forage quality were measured seasonally beneath the canopy of blue oak (Quercus douglasii) and in open grassland at the San Joaquin Experimental Range. At the March and peak standing crop sampling dates forage production was significantly greater (p=.05) beneath blue oak compared to open grassland. At most sampling dates, the...

  5. Molecular diversity among Turkish oaks (QUERCUS) using random ...

    African Journals Online (AJOL)

    aykut

    2013-11-06

    Nov 6, 2013 ... of the trees of temperate zone in north Hemisiphere with more than 500 species ... Kasapligil, 1992) as white oaks (Quercus L.), red oaks ... oaks. These are very problematic species in Turkey in the comparison to other members of the genus. The distribution area for Q. aucheri is only south weast region.

  6. Evaluation of extractive content in Albanian white oak ( Quercus ...

    African Journals Online (AJOL)

    , have an important impact on wood properties and its utilization. The study was carried on extractives content of white oak (Quercus petraea Liebl). Eighteen sawdust samples were taken from cuts in six different heights of three trees.

  7. Sessile oak (Quercus petraea agg. Ehrendorfer 1967) rare ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-01

    Sep 1, 2009 ... represent an exceptional potential for the conservation of sessile oak variability, which can have a very significant role also for ... were collected from each tree; that is from three trees in each cluster (some locations .... chloroplast DNA polymorphism of white oaks af section Quercus in the Central Balkans.

  8. Vegetation Change in Blue Oak Woodlands in California

    Science.gov (United States)

    Barbara A. Holzman; Barbara H. Allen-Diaz

    1991-01-01

    A preliminary report of a statewide project investigating vegetation change in blue oak (Quercus douglasii) woodlands in California is presented. Vegetation plots taken in the 1930s, as part of a statewide vegetation mapping project, were relocated and surveyed. Species composition, cover and tree stand structure data from the earlier study were...

  9. The Influence of Epiphytic Lichens on the Nutrient Cycling of a Blue Oak Woodland

    Science.gov (United States)

    Johannes M. Knops; Thomas H. H. Nash III; William H. Schlesinger

    1997-01-01

    We evaluated the importance of epiphytic lichens in the nutrient cycling of a blue oak (Quercus douglasii) woodland in California. Each oak tree contained an average of 3.8 kg lichen biomass, totaling 590 kg per ha. For comparison, oak leaf biomass was 958 kg per ha. We compared tree growth, volume and composition of throughfall (rainfall falling...

  10. In vitro propagation of northern red oak (Quercus rubra L.)

    Science.gov (United States)

    G. Vengadesan; Paula M. Pijut

    2009-01-01

    In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 µM 6-benzylaminopurine (BA), 0.45 ...

  11. Sessile oak (Quercus petraea agg. Ehrendorfer 1967) rare ...

    African Journals Online (AJOL)

    Sessile oak ( Quercus petraea agg. Ehrendorfer 1967) genetic variability in Serbia was estimated applying cpDNA universal primer pairs. Five different haplotypes were detected in the analyzed sample material from populations in Serbia. The areas in West and Southwest Serbia, with all their specificities, represent an ...

  12. Artificial Regeneration of Blue and Coast Live Oaks in the Central Coast

    Science.gov (United States)

    Tim R. Plumb; Bennie Hannah

    1991-01-01

    The primary goal of this study was to find economical and effective planting techniques that will ensure the establishment and early survival of coast live oak (Quercus agrifolia Née) and blue oak (Q. douglasii H. and A.) in the Central Coast region of California. Eight treatments were evaluated ranging from unprotected seed spots...

  13. The taxonomic status of the Mexican oak Quercus undata (Fagaceae, Quercus, Section Quercus El estatus taxonómico del encino mexicano Quercus undata (Fagaceae, Quercus, Sección Quercus

    Directory of Open Access Journals (Sweden)

    Jeffrey R. Bacon

    2011-12-01

    Full Text Available Quercus undata Trel. (Fagaceae, Quercus, Section Quercus has a complex taxonomic and nomenclatural history. Intensive sampling of oaks at the type locality of Q. undata Trel. in Durango, Mexico and evaluation of herbarium specimens and plants in the field indicate that Q. undata represents variation in Quercus chihuahuensis Trel. in white oak communities where introgressive hybridization among Q. chihuahuensis, Q. grisea Liebm., and a third white oak, Q. arizonica Sarg. made species identification difficult. Endlich's type specimen of Q. undata, as designated by Trelease, was apparently destroyed in bombing raids on Berlin during World War II, and we propose herein as lectotype the Trelease illustration of the type. An epitype is also designated in support of the lectotype, given that some features cannot be critically observed on the illustration. The long peduncles of the specimen illustrated by Trelease indicate a close relation to Q. chihuahuensis.Quercus undata Trel. (Fagaceae, Quercus, Section Quercus tiene una compleja historia taxonómica y de nomenclatura. Un muestreo intensivo de los encinos en la localidad tipo de Q. undata en Durango, México y análisis de ejemplares en herbario y en el campo indican que Q. undata representa variación en Q. chihuahuensis Trel. en los sitios donde la hibridación introgresiva entre Q. chihuahuensis, Q. grisea Liebm., y un tercer encino blanco, Q. arizonica Sarg., dificultan la identificación de especies. El ejemplar tipo designado por Trelease aparentemente fue destruido en el bombardeo de Berlín durante la Segunda Guerra Mundial, por lo que se propone como lectotipo a la ilustración del tipo en la obra de Trelease. Se designa también un epitipo dado que algunos rasgos no pueden ser críticamente observados en la ilustración. Los largos pedúnculos del espécimen ilustrado por Trelease indican la relación cercana a Q. chihuahuensis.

  14. Microsatellite Primer Development for Post Oak, Quercus stellata (Fagaceae

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    Warren B. Chatwin

    2014-10-01

    Full Text Available Premise of the study: The American Cross Timbers forest ecosystem runs from southeastern Kansas to Central Texas and is primarily composed of post oak (Quercus stellata. This old-growth forest currently occupies only about 2% of its ancestral range. To facilitate genetic research on this species, we developed microsatellite primers specific to post oak from reduced genomic libraries. Methods and Results: Two Q. stellata individuals, sampled from the northern and southern range of the post oak forest, were subject to genomic reduction and 454 pyrosequencing. Bioinformatic analysis identified putative microsatellites from which 12 polymorphic primer sets were screened on three populations. The number of alleles observed ranged from five to 20 across all populations, while observed and expected heterozygosity values ranged from 0.05 to 0.833 and 0.236 to 0.893, respectively, within individual populations. Conclusions: We report the development of microsatellite markers, specific to post oak, to aid the study of genetic diversity and population structure of extant forest remnants.

  15. Insect-oak interactions with coast live oak (Quercus agrifolia) and Engelmann oak (Q. engelmannii) at the acorn and seedling stage

    Science.gov (United States)

    Connell E. Dunning; Timothy D. Paine; Richard A. Redak

    2002-01-01

    We determined the impact of insects on both acorns and seedlings of coast live oak (Quercus agrifolia Nee) and Engelmann oak (Quercus engelmannii E. Greene). Our goals were to (1) identify insects feeding on acorns and levels of insect damage, and (2) measure performance and preference of a generalist leaf-feeding insect herbivore...

  16. Regeneration of red oak (Quercus rubra L.) using shelterwood systems: Ecophysiology, silviculture and management recommendations

    Science.gov (United States)

    Daniel C. Dey; William C. parker

    1996-01-01

    There is considerable interest in developing relaible methods for regenerating red oak (Quercus rubra) in Ontario. Traditional silviculture methods have not been successful in maintaining the curent levels of oak growing stock. In this paper, we review the ecology, physiology and reproductive biology of red oak. This discussion stresses the...

  17. Blue oak plant communities of southern San Luis Obispo and northern Santa Barbara Counties, California

    Science.gov (United States)

    Mark I. Borchert; Nancy D. Cunha; Patricia C. Krosse; Marcee L. Lawrence

    1993-01-01

    An ecological classification system has been developed for the Pacific Southwest Region of the Forest Service. As part of that classification effort, blue oak (Quercus douglasii) woodlands and forests of southern San Luis Obispo and northern Santa Barbara Counties in Los Padres National Forest were classified into I3 plant communities using...

  18. Thinning – a tool for restoration of California's Southern Sierra Nevada blue oak woodlands

    Science.gov (United States)

    Richard B. Standiford; Ralph L. Phillips; Neil K. McDougald

    2015-01-01

    Fire frequency on a blue oak (Quercus douglasii) dominated rangeland in California's southern Sierra Nevada foothills was approximately every 10 years until 1965, followed by a 30 year period of fire exclusion. This resulted in a dense tree overstory with small diameters, high crown cover, poor acorn and forage production, and limited...

  19. Genetic diversity and population structure of Raffaelea quercus-mongolicae, a fungus associated with oak mortality in South Korea

    Science.gov (United States)

    M. -S. Kim; P. A. Hohenlohe; K. -H. Kim; S. -T. Seo; Ned Klopfenstein

    2016-01-01

    Raffaelea quercus-mongolicae is a fungus associated with oak wilt and deemed to cause extensive oak mortality in South Korea. Since the discovery of this fungus on a dead Mongolian oak (Quercus mongolica) in 2004, the mortality continued to spread southwards in South Korea. Despite continued expansion of the disease and associated significant impacts on forest...

  20. Riparian valley oak (Quercus lobata) forest restoration on the middle Sacramento River, California

    Science.gov (United States)

    F. Thomas Griggs; Gregory H. Golet

    2002-01-01

    In 1989 The Nature Conservancy initiated a riparian horticultural restoration program on the floodplain of the middle Sacramento River, California. At nearly all restoration sites Valley oak (Quercus lobata Nee) comprised a major component of the planting design. Valley oaks are a keystone tree species of lowland floodplain habitats in California...

  1. Age structure and growth of California black oak (Quercus kelloggii) in the central Sierra Nevada, California

    Science.gov (United States)

    Barrett A. Garrison; Christopher D. otahal; Matthew L. Triggs

    2002-01-01

    Age structure and growth of California black oak (Quercus kelloggii) was determined from tagged trees at four 26.1-acre study stands in Placer County, California. Stands were dominated by large diameter (>20 inch dbh) California black oak and ponderosa pine (Pinus ponderosa). Randomly selected trees were tagged in June-August...

  2. Influence of Soil Type and Drainage on Growth of Swamp Chestnut Oak (Quercus Michauxii Nutt.) Seedlings

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    Donald D. Hook

    1969-01-01

    Swamp chestnut oak (Quercus michauxii Nutt.) seedlings were grown for 2 years in five soil types in drained and undrained pots. First-year height growth was related to soil type and pot drainage, but second-year height growth was related only to soil type. Results suggest that swamp chestnut oak is site-sensitive. But slow growth, a maximum of 2...

  3. Interspecific variation in functional traits of oak seedlings (Quercus ilex, Quercus trojana, Quercus virgiliana) grown under artificial drought and fire conditions.

    Science.gov (United States)

    Chiatante, D; Tognetti, R; Scippa, G S; Congiu, T; Baesso, B; Terzaghi, M; Montagnoli, A

    2015-07-01

    To face summer drought and wildfire in Mediterranean-type ecosystems, plants adopt different strategies that involve considerable rearrangements of biomass allocation and physiological activity. This paper analyses morphological and physiological traits in seedlings of three oak species (Quercus ilex, Quercus trojana and Quercus virgiliana) co-occurring under natural conditions. The aim of this study was to evaluate species-specific characteristics and the response of these oak seedlings to drought stress and fire treatment. Seedlings were kept in a growth chamber that mimicked natural environmental conditions. All three species showed a good degree of tolerance to drought and fire treatments. Differences in specific biomass allocation patterns and physiological traits resulted in phenotypic differences between species. In Q. ilex, drought tolerance depended upon adjustment of the allocation pattern. Q. trojana seedlings undergoing mild to severe drought presented a higher photosystem II (PSII) efficiency than control seedlings. Moreover, Q. trojana showed a very large root system, which corresponded to higher soil area exploitation, and bigger leaf midrib vascular bundles than the other two species. Morphological and physiological performances indicated Q. trojana as the most tolerant to drought and fire. These characteristics contribute to a high recruitment potential of Q. trojana seedlings, which might be the reason for the dominance of this species under natural conditions. Drought increase as a result of climate change is expected to favour Q. trojana, leading to an increase in its spatial distribution.

  4. Whole-transcriptome response to water stress in a California endemic oak, Quercus lobata

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    Paul F. Gugger; Juan Manuel Peñaloza-Ramírez; Jessica W. Wright; Victoria L. Sork; Jörg-Peter Schnitzler

    2016-01-01

    Reduced water availability during drought can create major stress for many plant species. Within a species, populations with a history of seasonal drought may have evolved the ability to tolerate drought more than those in areas of high precipitation and low seasonality. In this study, we assessed response to water stress in a California oak species, Quercus lobata Née...

  5. Predicting the height growth of oak species (Quercus) reproduction over a 23-year period following clearcutting

    Science.gov (United States)

    J. Travis Swaim; Daniel C. Dey; Michael R. Saunders; Dale R. Weigel; Christopher D. Thornton; John M. Kabrick; Michael A. Jenkins

    2016-01-01

    We resampled plots from a repeated measures study implemented on the Hoosier National Forest (HNF) in southern Indiana in 1988 to investigate the influence of site and seedling physical attributes on height growth and establishment success of oak species (Quercus spp.) reproduction in stands regenerated by the clearcut method. Before harvest, an...

  6. Growth and biomass distribution of cherrybark oak (Quercus pagoda Raf.) seedlings as influenced by light availability

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    Emile S. Gardiner; John D. Hodges

    1998-01-01

    Cherrybark oak (Quercus pagoda Raf.) seedlings were established and raised in the field under four light levels (100 percent. 53 percent, 27 percent or 8 percent of full sunlight) to study the effects of light availability on their shoot growth, biomass accumulation. and biomass distribution. After two growing seasons, greatest stem growth was observed on seedlings...

  7. Additivity in tree biomass components of Pyrenean oak (Quercus pyrenaica Willd.)

    Science.gov (United States)

    Joao P. Carvalho; Bernard R. Parresol

    2003-01-01

    In tree biomass estimations, it is important to consider the property of additivity, i.e., the total tree biomass should equal the sum of the components. This work presents functions that allow estimation of the stem and crown dry weight components of Pyrenean oak (Quercus pyrenaica Willd.) trees. A procedure that considers additivity of tree biomass...

  8. The phenolic extractives in southern red oak (Quercus falcata Michx. var. falcata)

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    Seiji Ohara; Richard W. Hemingway

    1989-01-01

    The bark of southern red oak (Quercus falcala Michx. var. falcala) is a rich source of quercitrin (quercetin-3-rhamnoside). It contains only low concentrations of (+)-catechin and no significant amounts of epicatechin or gallocatechin. The three major dimeric proanthocyanidins present are epicatechin-(4β→8)-...

  9. Somatic embryogenesis and plant regeneration of northern red oak (Quercus rubra L.)

    Science.gov (United States)

    G. Vengadesan; Paula M. Pijut

    2009-01-01

    A somatic embryogenesis protocol for plant regeneration of northern red oak (Quercus rubra) was established from immature cotyledon explants. Embryogenic callus cultures were induced on Murashige and Skoog medium (MS) containing 3% sucrose, 0.24% Phytagel™, and various concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) after 4 weeks of...

  10. Evaluation of extractive content in Albanian white oak (Quercus ...

    African Journals Online (AJOL)

    use

    2011-11-21

    Nov 21, 2011 ... three trees. The extraction is done with Soxhlet 250 ml capacity, for about 6 h. The content of extractives decreased from the base to the top of the tree and their content in wood was 4.7%. This result is near to those recommended in literature for Quercus sp. Key words: Extractives, extraction solvent, Soxhlet ...

  11. Molecular diversity among Turkish oaks ( QUERCUS ) using random ...

    African Journals Online (AJOL)

    Turkey is one of the most important region of the world according to oak species number and variation. In this study, species belonging to evergreen oaks in Turkey were investigated to solve taxonomic problems and to design the limit of taxa by using random amplified polymorphic DNA (RAPD) data. Here, three species of ...

  12. Does habitat matter in an urbanized landscape? The birds of the Garry oak (Quercus garryana) ecosystem of southeastern Vancouver Island

    Science.gov (United States)

    Richard E. Feldman; Pamela G. Krannitz

    2002-01-01

    Garry oak (Quercus garryana) was once a dominant habitat type on southeastern Vancouver Island, British Columbia but urbanization has severely fragmented and reduced its occurrence. This study tests whether bird abundance in remnant patches of Garry oak and adjacent Douglas-fir (Pseudotsuga menziesii) is related to Garry oak volume...

  13. Draft genome sequence of the fungus associated with oak-wilt mortality in South Korea, Raffaelea quercus-mongolicae KACC44405

    Science.gov (United States)

    Jongbum Jeon; Ki-Tae Kim; Hyeunjeong Song; Gir-Won Lee; Kyeongchae Cheong; Hyunbin Kim; Gobong Choi; Yong-Hwan Lee; Jane E. Stewart; Ned B. Klopfenstein; Mee-Sook Kim

    2017-01-01

    The fungus Raffaelea quercus-mongolicae is the causal agent of Korean oak wilt, a disease associated with mass mortality of oak trees (e.g., Quercus spp.). The fungus is vectored and dispersed by the ambrosia beetle, Platypus koryoensis. Here, we present the 27.0-Mb draft genome sequence of R. quercus-mongolicae strain KACC44405.

  14. Effectiveness of Quercus Branti Activated Carbon in Removal of Methylene Blue from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Abdolmotaleb Seidmohammadi

    2015-10-01

    Full Text Available Background & Aims of the Study: Dyes are one of the most contaminants in textile industrial wastewater that they are often carcinogenic, mutagenic and non-degradable. Therefore, with regard to environmental aspects, their removal from effluents is very essential. The purpose of this study was the perception of adsorption process and promotion of an economic technology for colored wastewater treatment. Therefore, activated carbon from Oak fruit bark was used as an effective and economic adsorbent. Materials & Methods: This study was performed at laboratory scale and batch system. At present study, the adsorbent surface properties was evaluated by use of the (FT-IR test and scanning electronic microscope (SEM. Also, effect of various operating parameters such as pH, contact time, adsorbent dose, initial dye concentration and temperature on dye removal from synthetic wastewater were studied. Results: In this study, maximum removal efficiency of methylene blue were achieved at optimal pH=6, reaction time 180 minutes, and adsorbent dose 2 gl-1. Methylene blue removal efficiency with initial concentration of 100 mg.l-1 was 91.08%. Conclusions: According to results, it was cleared that : Quercus branti activated carbon can be used as an effective and economic adsorbent in waste water treatment processes.

  15. Myxomycetes from the bark of the evergreen oak Quercus ilex

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    Wrigley de Basanta, Diana

    1998-06-01

    Full Text Available The results of 81 moist chamber cultures of bark from living Quercus ilex trees are reponed. A total of 37 taxa are cited, extending the number of species found on this substrate to 55. The presence of Licea deplanata on the Iberian Península is confirmed. Seven new records are included for the province of Madrid. Some data are contributed on species frequency and incubation times.Se presentan los resultados de 81 cultivos en cámara húmeda de corteza de Quercus ilex vivo. Se citan 37 táxones, que amplían a 55 el número de especies de mixomicetes encontrados sobre este sustrato. Se confirma la presencia en la Península Ibérica de Licea deplanata, y se incluyen siete nuevas citas para la provincia de Madrid. Se aportan datos sobre frecuencia de aparición y tiempos de incubación de algunas especies.

  16. Microsatellite markers for northern red oak (Fagaceae: Quercus rubra)

    Science.gov (United States)

    Preston R. Aldrich; Charles H. Michler; Weilin Sun; Jeanne Romero-Severson

    2002-01-01

    We provide primer sequences for 14 (GA)n microsatellite loci developed from northern red oak, an important timber species. We screened loci using two sets of samples. A parent-offspring set included DNA from seven acorns collected from one mother tree along with maternal DNA, to determine that all progeny carried a maternal allele at each locus....

  17. Genotypic variability of morphological characteristics of English oak (Quercus robur L acorn

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    Nikolić Nataša P.

    2002-01-01

    Full Text Available This paper deals with the acorn morphology (length, diameter and mass analyzed in seventeen English oak genotypes (Quercus robur Lfrom the English Oak Clonal Seed Orchard Banov Brod (Srem,Vojvodina. The highest values of acorn mass and length were measured in genotype 5. The largest diameters were measured in genotypes 6 and 21. Genotype 35 had the lowest acorn mass, length and diameter. The results from this study should serve as guidelines for the selection of trees yielding fruits possessing the desirable morphological characteristics.

  18. Fragmentation-related patterns of genetic differentiation in pedunculate oak (Quercus robur) at two hierarchical scales

    OpenAIRE

    Pohjanmies, Tähti; Elshibli, Sakina; Pulkkinen, Pertti; Rusanen, Mari; Vakkari, Pekka; Korpelainen, Helena; Roslin, Tomas

    2016-01-01

    Populations at species' range margins are expected to show lower genetic diversity than populations at the core of the range. Yet, long-lived, widespread tree species are expected to be resistant to genetic impoverishment, thus showing comparatively high genetic diversity within populations and low differentiation among populations. Here, we study the distribution of genetic variation in the pedunculate oak (Quercus robur L.) at its range margin in Finland at two hierarchical scales using 15 ...

  19. Development of Chloroplast and Nuclear DNA Markers for Chinese Oaks (Quercus Subgenus Quercus and Assessment of Their Utility as DNA Barcodes

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    Jia Yang

    2017-05-01

    Full Text Available Chloroplast DNA (cpDNA is frequently used for species demography, evolution, and species discrimination of plants. However, the lack of efficient and universal markers often brings particular challenges for genetic studies across different plant groups. In this study, chloroplast genomes from two closely related species (Quercus rubra and Castanea mollissima in Fagaceae were compared to explore universal cpDNA markers for the Chinese oak species in Quercus subgenus Quercus, a diverse species group without sufficient molecular differentiation. With the comparison, nine and 14 plastid markers were selected as barcoding and phylogeographic candidates for the Chinese oaks. Five (psbA-trnH, matK-trnK, ycf3-trnS, matK, and ycf1 of the nine plastid candidate barcodes, with the addition of newly designed ITS and a single-copy nuclear gene (SAP, were then tested on 35 Chinese oak species employing four different barcoding approaches (genetic distance-, BLAST-, character-, and tree-based methods. The four methods showed different species identification powers with character-based method performing the best. Of the seven barcodes tested, a barcoding gap was absent in all of them across the Chinese oaks, while ITS and psbA-trnH provided the highest species resolution (30.30% with the character- and BLAST-based methods, respectively. The six-marker combination (psbA-trnH + matK-trnK + matK + ycf1 + ITS + SAP showed the best species resolution (84.85% using the character-based method for barcoding the Chinese oaks. The barcoding results provided additional implications for taxonomy of the Chinese oaks in subg. Quercus, basically identifying three major infrageneric clades of the Chinese oaks (corresponding to Groups Quercus, Cerris, and Ilex referenced to previous phylogenetic classification of Quercus. While the morphology-based allocations proposed for the Chinese oaks in subg. Quercus were challenged. A low variation rate of the chloroplast genome, and

  20. Drought-induced photosynthetic inhibition and autumn recovery in two Mediterranean oak species (Quercus ilex and Quercus suber).

    Science.gov (United States)

    Vaz, M; Pereira, J S; Gazarini, L C; David, T S; David, J S; Rodrigues, A; Maroco, J; Chaves, M M

    2010-08-01

    Responses of leaf water relations and photosynthesis to summer drought and autumn rewetting were studied in two evergreen Mediterranean oak species, Quercus ilex spp. rotundifolia and Quercus suber. The predawn leaf water potential (Ψ(lPD)), stomatal conductance (gs) and photosynthetic rate (A) at ambient conditions were measured seasonally over a 3-year period. We also measured the photosynthetic response to light and to intercellular CO₂ (A/PPFD and A/C(i) response curves) under water stress (summer) and after recovery due to autumn rainfall. Photosynthetic parameters, Vc(max), J(max) and triose phosphate utilization (TPU) rate, were estimated using the Farquhar model. RuBisCo activity, leaf chlorophyll, leaf nitrogen concentration and leaf carbohydrate concentration were also measured. All measurements were performed in the spring leaves of the current year. In both species, the predawn leaf water potential, stomatal conductance and photosynthetic rate peaked in spring, progressively declined throughout the summer and recovered upon autumn rainfall. During the drought period, Q. ilex maintained a higher predawn leaf water potential and stomatal conductance than Q. suber. During this period, we found that photosynthesis was not only limited by stomatal closure, but was also downregulated as a consequence of a decrease in the maximum carboxylation rate (Vc(max)) and the light-saturated rate of photosynthetic electron transport (J(max)) in both species. The Vc(max) and J(max) increased after the first autumnal rains and this increase was related to RuBisCo activity, leaf nitrogen concentration and chlorophyll concentration. In addition, an increase in the TPU rate and in soluble leaf sugar concentration was observed in this period. The results obtained indicate a high resilience of the photosynthetic apparatus to summer drought as well as good recovery in the following autumn rains of these evergreen oak species.

  1. Moisture sorption isotherms and thermodynamic properties of Oak wood ( Quercus robur and Quercus canariensis): optimization of the processing parameters

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    Bahar, Rim; Azzouz, Soufien; Remond, Romain; Ouertani, Sahbi; Elaieb, Mohamed Taher; El Cafci, Mohamed Afif

    2017-05-01

    The aim of this paper was to determine the moisture desorption isotherms and essentials thermodynamic properties of two Oak wood varieties. Desorption isotherms were measured using a static gravimetric method at 50, 60, 70 and 80 °C within the range of 5-90 % relative humidity. The equilibrium moisture content decreased with increasing temperature and decreased with decreasing relative humidity at a constant temperature. The `Thermodynamic' sorption equation was found to be the best for describing the experimental moisture sorption isotherms of woods within the range of temperature and water activity investigated. The Fiber saturation point, deduced from the `Thermodynamic' model parameters, depends on the temperature and varying from 22.6 to 54.4 (% kg water/kg dry matter). Isosteric heat of desorption and differential entropy were calculated by applying Clausius-Clapeyron equation to the desorption data fitted by the `Thermodynamic' model. The isosteric heat of desorption and the differential entropy decreased with increasing moisture content according to an exponential law equation and varying from 2.03 to 31.14 kJ/mol and from 73.98 to 4.34 J/(mol K), respectively. The linear relationship between differential enthalpy and entropy satisfied the enthalpy-entropy compensation theory. The sign of Gibbs free energy was found to be positive (+283 J/mol) and (+97 J/mol) for Quercus robur and Quercus canariensis, respectively. The isokinetic temperature was found to be greater than the harmonic temperature. Based on the enthalpy-entropy compensation theory, it could be concluded that the moisture desorption isotherm of Oak wood is a non-spontaneous and enthalpy-controlled process.

  2. Artificial regeneration of major oak (Quercus) species in the eastern United States - a review of the literature

    Science.gov (United States)

    Daniel C. Dey; Douglass Jacobs; Ken McNabb; Gary W. Miller; V. Baldwin; G. Foster

    2008-01-01

    Although natural regeneration is often the best method for establishing new oak (Quercus spp.) stands, there are increasingly more situations in which high potential for oak regeneration failure dictates the use of artificial regeneration including direct seeding and planting seedlings. Additionally, afforestation planting programs frequently...

  3. Cardioprotective and hepatoprotective effects of ellagitannins from European oak bark (Quercus petraea L.) extract in rats.

    Science.gov (United States)

    Panchal, Sunil K; Brown, Lindsay

    2013-02-01

    Red wine contains many potentially bioactive polyphenols including resveratrol, catechins, anthocyanins and flavonoids as well as tannins derived from oak during maturation. This study examined the effects of a mixture of ellagitannins from oak bark (Quercus petraea L.) on cardiovascular, metabolic and liver changes in high-carbohydrate, high-fat diet-fed rats and in Spontaneously Hypertensive Rats (SHR). First, 8-week-old male Wistar rats were divided into four groups and given either cornstarch diet, cornstarch diet + oak bark extract (0.5 mL/kg food), high-carbohydrate, high-fat diet or high-carbohydrate, high-fat diet + oak bark extract (0.5 mL/kg food) for 16 weeks. Oak bark extract was added to the diets for last 8 weeks of the feeding period. Secondly, SHR aged 42 weeks fed on standard chow diet were divided into two groups with and without oak bark extract treatment for 12 weeks (0.5 mL/kg food). The high-carbohydrate, high-fat diet induced signs of metabolic syndrome along with cardiovascular remodelling and non-alcoholic steatohepatitis. Oak bark extract attenuated the signs of metabolic syndrome in high-carbohydrate, high-fat diet-fed rats and improved the structure and function of the heart and the liver. SHR after oak bark extract treatment for 12 weeks showed lower systolic blood pressure, lower cardiac fibrosis and cardiac stiffness and improved vascular reactivity. Oak bark extract containing ellagitannins improved cardiovascular, metabolic and liver parameters in these rat models of human disease, suggesting that part of the benefits attributed to red wine may be produced by these ellagitannins.

  4. Symptoms of the naturalisation of the Turkey oak (Quercus cerris L. in Polish forests

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    Danielewicz Władysław

    2016-09-01

    Full Text Available The Turkey oak (Quercus cerris L., the natural range of which embraces southern Europe and Asia Minor, belongs to trees rarely introduced into Polish forests. Tree stands where it appears, established before the Second World War, can be found in some 20 localities, mostly in the western part of the country. Because this species is capable of a natural renewal in a woodland environment, a research was made to find in what conditions and how far it undergoes spontaneous naturalisation. Three study sites were chosen in the forests of central Wielkopolska. An inventory was made of mature stands of the Turkey oak and its generative renewal. Plant communities in which the young generation of Q. cerris usually appears were characterised. It was found that self-sown seedlings of this species grew at a distance of up to 2,500 m from parent trees. The highest number and the greatest density of specimens of the secondary generation of the Turkey oak were found at ‘Racot’, which is a 100-hectare, mid-field woodland island where mesotrophic habitats predominate and where about 50% of the area is occupied by communities with manmade pine tree stands. At all sites, Q. cerris penetrates primarily this type of deformed phytocoenoses, developing mostly on former farmland. It has become a permanent component of the underbrush and undergrowth in them, and in some places, it also makes up the tree layer. It was observed that in the study area, it penetrated the woodland environment much more effectively than Quercus rubra, considered an invasive species. The expansion of the Turkey oak in several of the examined localities can be regarded as a basic manifestation of its naturalisation in places where there are phytocoenoses with pine stands in broad-leaf forest habitats in the neighbourhood of parent trees.

  5. Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States

    Science.gov (United States)

    Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G.

    2014-07-01

    Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6 %-248 %. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

  6. Evidence for hybridization and introgression within a species-rich oak (Quercus spp. community

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    Finkeldey Reiner

    2007-11-01

    Full Text Available Abstract Background Analysis of interspecific gene flow is crucial for the understanding of speciation processes and maintenance of species integrity. Oaks (genus Quercus, Fagaceae are among the model species for the study of hybridization. Natural co-occurrence of four closely related oak species is a very rare case in the temperate forests of Europe. We used both morphological characters and genetic markers to characterize hybridization in a natural community situated in west-central Romania and which consists of Quercus robur, Q. petraea, Q. pubescens, and Q. frainetto, respectively. Results On the basis of pubescence and leaf morphological characters ~94% of the sampled individuals were assigned to pure species. Only 16 (~6% individual trees exhibited intermediate morphologies or a combination of characters of different species. Four chloroplast DNA haplotypes were identified in the study area. The distribution of haplotypes within the white oak complex showed substantial differences among species. However, the most common haplotypes were present in all four species. Furthermore, based on a set of 7 isozyme and 6 microsatellite markers and using a Bayesian admixture analysis without any a priori information on morphology we found that four genetic clusters best fit the data. There was a very good correspondence of each species with one of the inferred genetic clusters. The estimated introgression level varied markedly between pairs of species ranging from 1.7% between Q. robur and Q. frainetto to 16.2% between Q. pubescens and Q. frainetto. Only nine individuals (3.4% appeared to be first-generation hybrids. Conclusion Our data indicate that natural hybridization has occurred at relatively low rates. The different levels of gene flow among species might be explained by differences in flowering time and spatial position within the stand. In addition, a partial congruence between phenotypically and genetically intermediate individuals was

  7. Effects of tornado damage, prescribed fire, and salvage logging on natural oak (Quercus spp.) regeneration in a xeric southern USA Coastal Plain oak/pine forest

    Science.gov (United States)

    Jeffery B. Cannon; J. Stephen Brewer

    2013-01-01

    Due in large part to fire exclusion, many oak-dominated (Quercus spp.) forests, woodlands, and savannas throughout eastern North America are being replaced by less diverse forest ecosystems. In the interior coastal plain of the southern United States, these forests are dominated in the mid- and understory by mesophytic species such as Acer...

  8. In vitro and in vivo assessment of anti-hyperglycemic and antioxidant effects of Oak leaves (Quercus convallata and Quercus arizonica) infusions and fermented beverages.

    Science.gov (United States)

    Gamboa-Gómez, Claudia I; Simental-Mendía, Luis E; González-Laredo, Rubén F; Alcantar-Orozco, Esteban J; Monserrat-Juarez, Victor H; Ramírez-España, Julio C; Gallegos-Infante, Jose Alberto; Moreno-Jiménez, Martha R; Rocha-Guzmán, Nuria E

    2017-12-01

    The aim of this study was to evaluate the anti-hyperglycemic and antioxidant effects of oak leaves infusions and fermented beverages from Quercus convallata and Q. arizonica in vitro and in vivo. Female C57BL/6 mice fed with high saturated fat and fructose diet-induced obesity were treated with oak leaves beverages (200 μL/per day equivalent to 15mg of lyophilized sample/Kg of body weight for infusions and 31mg of lyophilized sample/Kg of body weight for fermented beverages) for 3months and an oral glucose tolerance test (OGTT) was performed. Blood plasma was obtained for determination of glucose, lipid profile, and oxidative stress markers (ABTS, nitric oxide, and ORAC assays). Insulin resistance was estimated using the product of triglycerides and glucose (TyG). Oak leaves infusions and fermented beverages exhibited exerted inhibition of α-amylase (8-15% and 5-9%, respectively) and α-glucosidase (98% and 99%, respectively) enzymes. After OGTT, the groups treated with either oak leaves infusions or fermented beverages showed lower glucose levels compared with the obesity control group (18%) and a similar glucose tolerance to healthy control group. On long-term evaluation, intervention groups showed a significant reduction in fasting glucose concentrations (41-50% for oak leaves infusions and 52-66% for fermented beverages) and TyG index (4.2-4.6% for oak leaves infusions and 5.9-7.5% for fermented beverages) compared with the obese control group. Oak leaves infusions and fermented beverages had antioxidant potential in vitro and scavenging activity for radicals such as peroxyl and peroxynitrite anions. Our results suggest anti-hyperglycemic and antioxidant effects of beverages prepared with leaves of Quercus species in vitro and in vivo. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Impact of Climate Trends and Drought Events on the Growth of Oaks (Quercus robur L. and Quercus petraea (Matt. Liebl. within and beyond Their Natural Range

    Directory of Open Access Journals (Sweden)

    Diana Perkins

    2018-02-01

    Full Text Available Due to predicted climate change, it is important to know to what extent trees and forests will be impacted by chronic and episodic drought stress. As oaks play an important role in European forestry, this study focuses on the growth response of sessile oak (Quercus petraea (Matt. Liebl. and pedunculate oak (Quercus robur (L. under contrasting climatic conditions. Analyses cover both site conditions of their natural occurrence (Southern Germany and Northeast Italy and site conditions beyond their natural range (South Africa. The sites beyond their natural range represent possible future climate conditions. Tree-ring series from three different sites were compared and analysed using dendrochronological methods. The long-term growth development of oak trees appears to be similar across the sites, yet the growth level over time is higher in the drier and warmer climate than in the temperate zone. When compared with previous growth periods, growth models reveal that oak trees grew more than expected during the last decades. A recent setback in growth can be observed, although growth is still higher than the model predicts. By focusing on the short-term reactions of the trees, distinct drought events and periods were discovered. In each climatic region, similar growth reactions developed after drought periods. A decline in growth rate occurred in the second or third year after the drought event. Oaks in South Africa are currently exposed to a warmer climate with more frequent drought events. This climatic condition is a future prediction also for Europe. In view of this climate change, we discuss the consequences of the long- and short- term growth behaviour of oaks grown in the climate of South Africa for a tree species selection that naturally occurs in Europe.

  10. Interactive effects of O3 exposure on California black oak (Quercus kelloggii Newb.) seedlings with and without N amendment

    Science.gov (United States)

    T. Handley; Nancy Grulke

    2008-01-01

    We examined the short-term separate and combined effects of simulated nitrogen (N) deposition (fertilization) and ozone (O3) exposure on California black oak seedlings (Quercus kelloggii Newb.), an ecologically important tree of the San Bernardino Mountains downwind of Los Angeles. Realistic concentrations of O3...

  11. Comparative gas-exchange in leaves of intact and clipped, natural and planted cherybark oak (Quercus pagoda Raf.) seedlings

    Science.gov (United States)

    Brian R. Lockhart; John D. Hodges

    1994-01-01

    Gas-exchange measurements, including CO2-exchange rate (net photosynthesis), stomatal conductance, and transpiration, were conducted on intact and clipped cherrybark oak (Quercus pagoda Raf.) seedlings growing inthe field and in a nursery bed. Seedlings inthe field, released frommidstory and understory woody competition, showed...

  12. Comparative gas-exchange in leaves of intact and clipped, natural and planted cherrybark oak (Quercus pagoda Raf.) seedlings

    Science.gov (United States)

    Brian R. Lockhart; John D. Hodges

    2005-01-01

    Gas-exchange measurements, including C022-exchange rate (net photosynthesis), stomatal conductance, and transpiration, were conducted on intact and clipped cherrybark oak (Quercus pagoda Raf.) seedlings growing in the field and in a nursery bed. Seedlings in the field, released from midstory and understory woody competition,...

  13. Historical jigsaw puzzles: piecing together the understory of Garry Oak (Quercus garryana) ecosystems and the implications for restoration

    Science.gov (United States)

    Carrina Maslovat

    2002-01-01

    Ecosystem restoration requires a set of reference vegetation conditions which are difficult to find for Garry oak (Quercus garryana) ecosystems in Canada because contemporary sites have been drastically altered. A survey of historical information provides only limited clues about the original understory vegetation. Although there is considerable...

  14. Pedunculate oak forests (Quercus robur L. survey in the Ticino Regional Park (Italy by remote sensing

    Directory of Open Access Journals (Sweden)

    Rossini M

    2007-01-01

    Full Text Available Pedunculate oak forests (Quercus robur L. in the Ticino Regional Park (Italy show sensible damage conditions due to different environmental stresses: insect attacks, summer drought and air pollution. Knowing whether oaks are healthy or stressed can provide useful information in order to conserve the forest ecosystems and avoid the lost of valuable natural resources. Environmental stresses can affect tree biochemical and structural variables, such as the concentration, composition and efficiency in light harvesting of foliar pigments, and the Leaf Area Index (LAI. Interest in the use of these variables for forest condition assessment has recently increased because they can be indirectly estimated from remote observations at leaf and canopy level. In particular, in this research we found that total chlorophyll (Chl concentration, a biochemical variable related to crown discoloration rate, was the most suitable variable for the detection of pedunculate oak decline in the Ticino Park. A regression analysis between Chl concentration and optical indices computed from hyperspectral MIVIS data was performed in order to estimate Chl concentration from remote observations. The good correlation between field measurements of Chl concentration and MIVIS optical indices allowed the development of a model to map Chl concentration across the Ticino Park forested area. Promising results demonstrated that remotely sensed data can provide an accurate estimation of Chl concentration and indicated the potential of this technique for forest condition monitoring.

  15. Properties of Hungarian oak(quercus conferta Kit. wood from the Hilandar Monastery forest

    Directory of Open Access Journals (Sweden)

    Popović Zdravko

    2007-01-01

    Full Text Available This paper presents the study results of the basic physical and strength properties of Hungarian oak (Quercus conferta Kit. wood from the Kakovo Monastery forests of Hilandar Monastery in Greece. Wood properties were analyzed in detail, as an indispensable proof of wood quality and its use for joinery, interiors and wooden floors. The basic physical properties of wood (moisture content at the time of tree felling, density and volume porosity and the basic strength properties (compressive strength, bending strength and module of elasticity were researched. The results are presented in Tables and in Diagrams with statistical parameters and compared to the literature data. The correlation of the study properties of wood was also analyzed.

  16. Influence of overstory density on ecophysiology of red oak (Quercus rubra) and sugar maple (Acer saccharum) seedlings in central Ontario shelterwoods

    Science.gov (United States)

    William C. Parker; Daniel C. Dey

    2008-01-01

    A field experiment was established in a secondgrowth hardwood forest dominated by red oak (Quercus rubra L.) to examine the effects of shelterwood overstory density on leaf gas exchange and seedling water status of planted red oak, naturally regenerated red oak and sugar maple (Acer saccharum Marsh.) seedlings during the first...

  17. The macrofungal diversity and community of Atlantic oak (Quercus petraea and Q. robur forests in Ireland

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    Harrington, Thomas J.

    2012-06-01

    Full Text Available The oak species Quercus petraea and Q. Robur are dominant canopy tree species of native deciduous forests in Ireland and coastal regions of Western Europe. These forests are typically plant species-rich, and can also have a rich fungal flora. This survey examined macrofungi found in five native oak sites across Ireland over three years. Overall, 94 macrofungal species belonging to 39 genera were discovered with Mycena, Lactarius, Russula and Cortinarius the most species-rich genera. The species accumulation curve did not show signs of levelling off, indicating that more sampling would reveal more new species. Species richness estimation using the Chao2 estimator indicated that up to 135 species may be present across all of our plots, with individual plots receiving estimates from 19 to 61 species per plot. Sampled-based rarefaction analysis showed no significant differences in macrofungal species richness between our plots. The five most common species were Laccaria amethystina, L. laccata, Stereum hirsutum, Armillaria mellea and Cortinarius flexipes. Comparisons of the results with results from oak forests in similar regions found that the communities in Great Britain were most similar to those found in Ireland. There were some key oak forest distinguishing fungal species from the family Boletaceae lacking from Irish oak forests. It is hypothesised that the historic deforestation of Ireland, caused a reduction of suitable habitats for Irish oak associated macrofungi, leading to the unspecific mycota found in the oak forests of this study. The threats to Atlantic oak forests in Ireland are briefly discussed.Las especies de Quercus petraea y Q. Robur se encuentran en bosques de Irlanda y regiones de influencia atlántica de Europa Occidental. Estos bosques, típicamente ricos en especies de plantas, presentan una abundante micobiota. Este estudio examina la diversidad de macromicetes en cinco bosques naturales de roble en Irlanda durante un

  18. A comprehensive assessment of the transcriptome of cork oak (Quercus suber) through EST sequencing.

    Science.gov (United States)

    Pereira-Leal, José B; Abreu, Isabel A; Alabaça, Cláudia S; Almeida, Maria Helena; Almeida, Paulo; Almeida, Tânia; Amorim, Maria Isabel; Araújo, Susana; Azevedo, Herlânder; Badia, Aleix; Batista, Dora; Bohn, Andreas; Capote, Tiago; Carrasquinho, Isabel; Chaves, Inês; Coelho, Ana Cristina; Costa, Maria Manuela Ribeiro; Costa, Rita; Cravador, Alfredo; Egas, Conceição; Faro, Carlos; Fortes, Ana M; Fortunato, Ana S; Gaspar, Maria João; Gonçalves, Sónia; Graça, José; Horta, Marília; Inácio, Vera; Leitão, José M; Lino-Neto, Teresa; Marum, Liliana; Matos, José; Mendonça, Diogo; Miguel, Andreia; Miguel, Célia M; Morais-Cecílio, Leonor; Neves, Isabel; Nóbrega, Filomena; Oliveira, Maria Margarida; Oliveira, Rute; Pais, Maria Salomé; Paiva, Jorge A; Paulo, Octávio S; Pinheiro, Miguel; Raimundo, João A P; Ramalho, José C; Ribeiro, Ana I; Ribeiro, Teresa; Rocheta, Margarida; Rodrigues, Ana Isabel; Rodrigues, José C; Saibo, Nelson J M; Santo, Tatiana E; Santos, Ana Margarida; Sá-Pereira, Paula; Sebastiana, Mónica; Simões, Fernanda; Sobral, Rómulo S; Tavares, Rui; Teixeira, Rita; Varela, Carolina; Veloso, Maria Manuela; Ricardo, Cândido P P

    2014-05-15

    Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management. We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of ~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at http://www.corkoakdb.org. This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.

  19. Comparative Pollen Morphological Analysis and Its Systematic Implications on Three European Oak (Quercus L., Fagaceae Species and Their Spontaneous Hybrids.

    Directory of Open Access Journals (Sweden)

    Dorota Wrońska-Pilarek

    Full Text Available Pollen morphology of three parental Quercus species (Q. robur L., Q. petraea (Matt Liebl, Q. pubescens Willd. and two spontaneous hybrids of these species (Q. ×calvescens Vuk. = Q. petraea × Q. pubescens and Q. ×rosacea Bechst. = Q. robur × Q. petraea was investigated in this study. The pollen originated from 18 natural oak sites and 67 individuals (oak trees. Each individual was represented by 30 pollen grains. In total, 2010 pollen grains were measured. They were analysed for nine quantitative and four qualitative features. Pollen size and shape were important features to diagnosing Quercus parental species and hybrids. On the basis of exine ornamentation, it was possible to identify only Q. pubescens, while the remaining species and hybrids did not differ significantly with respect to this feature. The determination of the diagnostic value of endoaperture features requires further palynological studies. On the basis of pollen size and shape Q. robur × Q. petraea was clearly separated. Grouping of 67 oak trees on the basis of pollen grain features has shown that individuals from different as well as same taxa occurred in the same groups. Likewise, with respect to natural sites, oak trees originating from the same places as well as from geographically distant ones, grouped together. Pollen morphological features allow to distinguish a part of the studied Quercus taxa. Therefore, it can be used as an auxiliary feature in the taxonomy.

  20. Physiological function of insoluble dietary fiber prepared from exploded oak wood (Quercus mongolica).

    Science.gov (United States)

    Yang, Jae-Kyung; Choi, Myung-Suk; Kim, Chang-Joon; Shin, Yong-Seung; Han, Dae-Yong; Han, Sang-Woo; Lim, Bu-Kug; Lee, Jong-Yoon; Rhee, Soon-Jae; Kim, Eun-Hee; Kim, Gon-Sup

    2006-01-01

    This study investigated the production of insoluble dietary fiber using exploded and chemically treated oak wood (Quercus mongolica) and the physiological functions of prepared insoluble dietary fiber in laboratory animals. To produce high quality insoluble dietary fiber, the steam explosion treatment was performed at 25 kgf/cm2 pressure for 6 minutes. In the chemical analysis of insoluble dietary fiber, exploded oak wood was pretreated by 1% sodium hydroxide solution. The insoluble dietary fiber contained 7.6% residual lignin and 61.7% of alpha-cellulose. In order to compare the physiological functions of prepared insoluble dietary fiber with those of commercial insoluble dietary fiber, Sprague-Dawley male rats weighing 100 +/- 10 g were randomly assigned to one normal diet and five high cholesterol diets, containing 1% cholesterol. The high cholesterol diet groups were classified as the fiber-free diet (FF group), 5% commercial alpha-cellulose diet group (5C group), 10% commercial alpha-cellulose group (10C group), 5% insoluble dietary fiber group (5M group) and 10% insoluble dietary fiber group (10M group). Food intake, weight gain and food efficiency ratio in high cholesterol groups were significantly higher than those of the normal group, but there were no significant differences among the high cholesterol diet groups. In addition, there were no significant differences in the weights of liver, kidney and small intestine in insoluble dietary fiber-supplemented groups. Cecum weights in all insoluble dietary fiber groups were significantly higher than those of the FF group. There were no significant differences in the activities of the glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) among the insoluble dietary fiber-supplemented groups. In conclusion, the prepared insoluble dietary fiber and the commercially available insoluble fiber showed the same physiological effects. Moreover, the preparation method for the insoluble dietary

  1. Measuring vessel dimensions in oak wood (Quercus sp.) on macroscopic level with image analysis system - Lucia G

    OpenAIRE

    Merela, Maks; Oven, Primož; Čufar, Katarina

    2005-01-01

    System for image analysis Lucia G was used for measuring vessel dimensions of oak wood (Quercus sp.) on macroscopic level. We present the problem of sample preparation as well as capturing and processing of images for automatic measurements of diameters, areas and perimeters of early wood vessels. After testing various methods of sample preparation we found out that the best results were obtained when the samples were sanded with paper of granulation 320 and the surface stained with black alc...

  2. Phylogeographical variation of chloroplast DNA in holm oak (Quercus ilex L.).

    Science.gov (United States)

    Lumaret, R; Mir, C; Michaud, H; Raynal, V

    2002-11-01

    Variation in the lengths of restriction fragments (RFLPs) of the whole chloroplast DNA molecule was studied in 174 populations of Quercus ilex L. sampled over the entire distribution of this evergreen and mainly Mediterranean oak species. By using five endonucleases, 323 distinct fragments were obtained. From the 29 and 17 cpDNA changes identified as site and length mutations, respectively, 25 distinct chlorotypes were distinguished, mapped and treated cladistically with a parsimony analysis, using as an outgroup Q. alnifolia Poech, a closely related evergreen oak species endemic to Cyprus where Q. ilex does not grow. The predominant role of Q. ilex as maternal parent in hybridization with other species was reflected by the occurrence of a single very specific lineage of related chlorotypes, the most ancestral and recent ones being located in the southeastern and in the northwestern parts of the species' geographical distribution, respectively. The lineage was constituted of two clusters of chlorotypes observed in the 'ilex' morphotyped populations of the Balkan and Italian Peninsulas (including the contiguous French Riviera), respectively. A third cluster was divided into two subclusters identified in the 'rotundifolia' morphotyped populations of North Africa, and of Iberia and the adjacent French regions, respectively. Postglacial colonization probably started from three distinct southerly refugia located in each of the three European peninsulas, and a contact area between the Italian and the Iberian migration routes was identified in the Rhône valley (France). Chlorotypes identical or related to those of the Iberian cluster were identified in the populations from Catalonia and the French Languedoc region, which showed intermediate morphotypes, and in the French Atlantic populations which possessed the 'ilex' morphotype, suggesting the occurrence of adaptive morphological changes in the northern part of the species' distribution.

  3. Effects of cadmium on cork oak (Quercus suber L.) plants grown in hydroponics.

    Science.gov (United States)

    Gogorcena, Yolanda; Larbi, Ajmi; Andaluz, Sofia; Carpena, Ramón O; Abadía, Anunciación; Abadía, Javier

    2011-12-01

    Cork oak (Quercus suber L.) is an autochthonous tree species that is being used for reforestation in heavy-metal-contaminated areas in Spain. A hydroponics experiment was carried out to characterize the effects of Cd on several morphological and physiological parameters in this species, including shoot length, nutrient concentrations and allocation in different organs, leaf pigment concentrations, photosynthetic efficiency, root ferric chelate reductase (FCR) activity and organic acid concentrations in xylem sap. Four different Cd treatments were applied, adding Cd chelated with EDTA or as chloride salt at two different concentrations (10 and 50 µM Cd). After 1 month of Cd treatment, plant growth was significantly inhibited in all treatments. Results indicate that Cd accumulates in all organs 7- to 500-fold when compared with control plants. The highest Cd concentration was found in the 50 µM CdCl(2) treatment, which led to concentrations of ~30, 123 and 1153 µg Cd g(-1) dry weight in leaves, stems and roots, respectively. In the strongest Cd treatments the concentrations of P and Ca decreased in some plant parts, whereas the Mn leaf concentrations decreased with three of the four Cd treatments applied. The concentrations of chlorophyll and carotenoids on an area basis decreased, whereas the (zeaxanthin plus antheraxanthin)/(total violaxanthin cycle carotenoids) ratio and the non-photochemical quenching increased significantly in all Cd treatments. Cadmium treatments caused significant increases in the activity of the enzyme FCR in roots and in the concentrations of organic acids in xylem sap. Some of the physiological changes found support the fact that Cd induces a deficiency of Fe in cork oak, although the plant Fe concentrations were not reduced significantly. At higher concentrations the effects of Cd were more pronounced, and were more marked when Cd was in the free ion form than when present in the form of Cd-EDTA.

  4. The Occurrence of Charcoal Disease Caused by Biscogniauxia mediterranea on Chestnut-Leaved Oak (Quercus castaneifolia) in the Golestan Forests of Iran

    NARCIS (Netherlands)

    Mirabolfathy, M.; Groenewald, J.Z.; Crous, P.W.

    2011-01-01

    The chestnut-leaved oak (Quercus castaneifolia) is native to the Alborz Mountains, including the Golestan Forests, in northern Iran. Trees grow up to 35 (-50) m tall with a trunk up to 2.5 (-3.5) m in diameter. During 2010, we received reports of a decline of oak trees in the Ghorogh Region of the

  5. Diseases of the shoots and bark of oaks in the FRG. [Phomopsis quercella; Phomopsis quercina; Fusicoccum quercus; Colpoma quercinum; Pezicula cinnamomea; Stereum rugosum; Armillaria mellea; Ceratocystis piceae

    Energy Technology Data Exchange (ETDEWEB)

    Butin, H.

    1987-03-01

    Several fungi known to cause diseases in oak trees and which have been found in recent years in the Federal Republic of Germany are discussed with regard to their pathogenicity. These include: Phomopsis quercella, Ph. quercina, Fusicoccum quercus, Colpoma quercinum. The proportion of red oaks afflicted with Pezicula cinnamomea, Stereum rugosum, and Armillaria mellea was considerable. The importance of Ceratocystis piceae in the development of oak disease is discussed.

  6. Development of molecular markers for determining continental origin of wood from White Oaks (Quercus L. sect. Quercus)

    Science.gov (United States)

    Hilke Schroeder; Richard Cronn; Yulai Yanbaev; Tara Jennings; Malte Mader; Bernd Degen; Birgit Kersten; Dusan Gomory

    2016-01-01

    To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica...

  7. The ancient blue oak woodlands of California: longevity and hydroclimatic history

    Science.gov (United States)

    Stahle, D.W.; Griffin, R.D.; Meko, D.M.; Therrell, M.D.; Edmondson, J.R.; Cleaveland, M.K.; Burnette, D.J.; Abatzoglou, J.T.; Redmond, K.T.; Dettinger, M.D.; Cayan, D.R.

    2013-01-01

    Ancient blue oak trees are still widespread across the foothills of the Coast Ranges, Cascades, and Sierra Nevada in California. The most extensive tracts of intact old-growth blue oak woodland appear to survive on rugged and remote terrain in the south Coast Ranges and on the foothills west and southwest of Mt. Lassen. In our sampling of old-growth stands, most blue oak appear to have recruited to the canopy in the mid- to late-19th century. The oldest living blue oak tree sampled was over 459-years old and several dead blue oak logs had over 500 annual rings. Precipitation sensitive tree-ring chronologies up to 700-years long have been developed from old blue oak trees and logs. Annual ring-width chronologies of blue oak are strongly correlated with cool season precipitation totals, streamflow in the major rivers of California, and the estuarine water quality of San Francisco Bay. A new network of 36 blue oak chronologies records spatial anomalies in growth that arise from latitudinal changes in the mean storm track and location of landfalling atmospheric rivers. These long, climate-sensitive blue oak chronologies have been used to reconstruct hydroclimatic history in California and will help to better understand and manage water resources. The environmental history embedded in blue oak growth chronologies may help justify efforts to conserve these authentic old-growth native woodlands.

  8. Removal of acorns of the alien oak Quercus rubra on the ground by scatter-hoarding animals in Belgian forests

    Directory of Open Access Journals (Sweden)

    Merceron, NR.

    2017-01-01

    Full Text Available Description of the subject. Quercus rubra L. is considered an invasive species in several European countries. However, little is known about its dispersal in the introduced range. Objectives. We investigated the significance of animal dispersal of Q. rubra acorns on the ground by vertebrates in its introduced range, and identified the animal species involved. Method. During two consecutive autumns, the removal of acorns from Q. rubra and from a native oak was assessed weekly in forest sites in Belgium. We used automated detection camera traps to identify the animals that removed acorns. Results. Quercus rubra acorns were removed by wood mice (Apodemus sylvaticus L., red squirrels (Sciurus vulgaris L., rats (Rattus sp., and wild boars (Sus scrofa L.. The two former are scatter-hoarding rodents and can be considered potential dispersers. Conclusions. Dispersal of Q. rubra acorns in Western Europe by scatter-hoarding animals may help the species increasingly colonize forest ecosystems.

  9. Spatiotemporal variation in acorn production and damage in a Spanish holm oak (Quercus ilex dehesa

    Directory of Open Access Journals (Sweden)

    L. Perez Izquierdo

    2013-04-01

    Full Text Available Aim of study. There is a lack of knowledge about spatio-temporal patterns of acorn production in dehesas, especially regarding the influence of different agents causing acorn damage. We examined the spatial and temporal variability on acorn production and damage in four stands within a dehesa farm in 1997, 1998 and 1999.Area of study. The study was carried out in a 1800 ha dehesa farm of Cáceres province, western Spain.Material and Methods. Acorns were sampled by means of seed traps placed in the canopy of six holm oak trees per stand. Acorn collected in it were counted and assessed for damage by Curculio weevils, Cydia moths and the bacterial pathogen Brenneria quercina.Main results. Mean acorn production for the whole study period was 44.60 acorns m-2, which did not vary significantly either among stands or among years. The variability among individual trees was very high (0-300 acorns m-2. The rate of infestation by Curculio was 7.64 ± 10.72 %, by Cydia was 1.76 ± 3.33 %, whereas 10.29 ± 16.12 % of acorns were infested by Brenneria. We found no significant spatial differences, but the rates of acorn loss by insects varied among years. These rates were independent of annual acorn production and there was no correlation among damages by different pests, except between Curculio and Cydia in two crop years.Research highlights. It can be concluded that acorn crops are synchronized at the within-farm level and that the temporal variation in acorn damages can be independent of crop size.Keywords: Acorn production; Brenneria; Curculio; Cydia; dehesa; Quercus ilex; spatio-temporal variation.

  10. Molecular, morphological, and ecological niche differentiation of sympatric sister oak species, Quercus virginiana and Q. geminata (Fagaceae).

    Science.gov (United States)

    Cavender-Bares, Jeannine; Pahlich, Annette

    2009-09-01

    The genus Quercus (the oaks) is notorious for interspecific hybrization, generating questions about the mechanisms that permit coexistence of closely related species. Two sister oak species, Quercus virginiana and Q. geminata, occur in sympatry in Florida and throughout the southeastern United States. In 11 sites from northern and southeastern regions of Florida, we used a leaf-based morphological index to identify individuals to species. Eleven nuclear microsatellite markers significantly differentiated between the species with a high correspondence between molecular and morphological typing of specimens. Nevertheless, Bayesian clustering analysis indicates interspecific gene flow, and six of 109 individuals had mixed ancestry. The identity of several individuals also was mismatched using molecular markers and morphological characters. In a common environment, the two species performed differently in terms of photosynthetic performance and growth, corresponding to their divergent ecological niches with respect to soil moisture and other edaphic properties. Our data support earlier hypotheses that divergence in flowering time causes assortative mating, allowing these ecologically distinct sister species to occur in sympatry. Limited gene flow that permits ecological differentiation helps to explain the overdispersion of oak species in local communities.

  11. Development of Molecular Markers for Determining Continental Origin of Wood from White Oaks (Quercus L. sect. Quercus).

    Science.gov (United States)

    Schroeder, Hilke; Cronn, Richard; Yanbaev, Yulai; Jennings, Tara; Mader, Malte; Degen, Bernd; Kersten, Birgit

    2016-01-01

    To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica as a reference, we identified 861 variant sites (672 single nucleotide polymorphisms (SNPs); 189 insertion/deletion (indel) polymorphism) from representative species of three continents (Q. mongolica from Asia; Q. petraea and Q. robur from Europe; Q. alba from North America), and we identified additional chloroplast polymorphisms in pools of 20 individuals each from Q. mongolica (789 variant sites) and Q. robur (346 variant sites). Genome sequences were screened for indels to develop markers that identify continental origin of oak species, and that can be easily evaluated using a variety of detection methods. We identified five indels and one SNP that reliably identify continent-of-origin, based on evaluations of up to 1078 individuals representing 13 white oak species and three continents. Due to the size of length polymorphisms revealed, this marker set can be visualized using capillary electrophoresis or high resolution gel (acrylamide or agarose) electrophoresis. With these markers, we provide the wood trading market with an instrument to comply with the U.S. and European laws that require timber companies to avoid the trade of illegally harvested timber.

  12. Development of Molecular Markers for Determining Continental Origin of Wood from White Oaks (Quercus L. sect. Quercus.

    Directory of Open Access Journals (Sweden)

    Hilke Schroeder

    Full Text Available To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica as a reference, we identified 861 variant sites (672 single nucleotide polymorphisms (SNPs; 189 insertion/deletion (indel polymorphism from representative species of three continents (Q. mongolica from Asia; Q. petraea and Q. robur from Europe; Q. alba from North America, and we identified additional chloroplast polymorphisms in pools of 20 individuals each from Q. mongolica (789 variant sites and Q. robur (346 variant sites. Genome sequences were screened for indels to develop markers that identify continental origin of oak species, and that can be easily evaluated using a variety of detection methods. We identified five indels and one SNP that reliably identify continent-of-origin, based on evaluations of up to 1078 individuals representing 13 white oak species and three continents. Due to the size of length polymorphisms revealed, this marker set can be visualized using capillary electrophoresis or high resolution gel (acrylamide or agarose electrophoresis. With these markers, we provide the wood trading market with an instrument to comply with the U.S. and European laws that require timber companies to avoid the trade of illegally harvested timber.

  13. Red Oak (Quercus rubra, L.) acron collection, nursery culture and direct seeding: A literature review

    Science.gov (United States)

    Daniel C. Dey

    1995-01-01

    The artificial regeneration of red oak by planting or direct seeding is an important method for restoring oak in ecosystems where it has been lost as a result of past management practices. Planting and direct seeding can also be used to supplement natural oak regeneration and to ensure that sufficient oak reproduction is in place when overstories are removed through...

  14. Tree species richness, diversity, and regeneration status in different oak (Quercus spp. dominated forests of Garhwal Himalaya, India

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    Sushma Singh

    2016-09-01

    Full Text Available Himalayan forests are dominated by different species of oaks (Quercus spp. at different altitudes. These oaks are intimately linked with hill agriculture as they protect soil fertility, watershed, and local biodiversity. They also play an important role in maintaining ecosystem stability. This work was carried out to study the diversity and regeneration status of some oak forests in Garhwal Himalaya, India. A total of 18 tree species belonging to 16 genera and 12 families were reported from the study area. Species richness varied for trees (4–7, saplings (3–10, and seedlings (2–6. Seedling and sapling densities (Ind/ha varied between 1,376 Ind/ha and 9,600 Ind/ha and 167 Ind/ha and 1,296 Ind/ha, respectively. Species diversity varied from 1.27 to 1.86 (trees, from 0.93 to 3.18 (saplings, and from 0.68 to 2.26 (seedlings. Total basal area (m2/ha of trees and saplings was 2.2–87.07 m2/ha and 0.20–2.24 m2/ha, respectively, whereas that of seedlings varied from 299 cm2/ha to 8,177 cm2/ha. Maximum tree species (20–80% had “good” regeneration. Quercus floribunda, the dominant tree species in the study area, showed “poor” regeneration, which is a matter of concern, and therefore, proper management and conservation strategies need to be developed for maintenance and sustainability of this oak species along with other tree species that show poor or no regeneration.

  15. Foliar nutrients explain goldspotted oak borer, Agrilus auroguttatus, adult feeding preference among four California oak species

    Science.gov (United States)

    Yigen. Chen; Tom. W. Coleman; Michael. I. Jones; Mary. L. Flint; Steven. J. Seybold

    2013-01-01

    Adults of the invasive goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), consumed foliar weight in no-choice feeding tests of, in descending order, California black oak Quercus kelloggii Newb., Engelmann oak, Quercus engelmannii Greene, coast live oak, Quercus...

  16. Coarse woody debris metrics in a California oak woodland

    Science.gov (United States)

    William D. Tietje; Michael A. Hardy; Christopher C. Yim

    2015-01-01

    Little information is available on the metrics of coarse woody debris (CWD) in California oak woodland, most notably at the scale of the stand and woodland type. In a remote part of the National Guard Post, Camp Roberts, that has not burned in over a half century, we tallied 314 pieces of CWD in a blue oak (Quercus douglasii)-coast live oak (

  17. Using Landsat 8 imagery in detecting cork oak (Quercus suber L. woodlands: a case study in Calabria (Italy

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    Giuseppe Modica

    2016-12-01

    Full Text Available In the Mediterranean basin, cork oak (Quercus suber L. woodlands are characteristic and widespread forestry ecosystems. Though presenting significant economic potential as a renewable resource, they are not adequately valorised, in spite of a growing market demand for cork and cork-based products, which are appreciated, today, for their use in sustainable building. In this respect, cork meets the needs of the building industry in responding to the growing demand for quality products, which are eco- and energy-friendly and hygienically safe. Moreover, European cultural and biodiversity value has been attributed to cork oak woodlands and their most significant examples have been included in the Natura 2000 framework. So far, in some countries like Italy, the territorial distribution and characterisation of cork oak woodlands have not been adequately investigated. This study provides a method for mapping the actual presence of cork oak woodlands and for assessing their potential distribution. Special attention was given to the characterisation of cork oak spectral signature. To this end, Landsat 8 satellite images, digital photointerpretation and in situ surveys were implemented. The work carried out allows assessing the effectiveness of GIS and remote sensing techniques coupled with ancillary data and tools, and their applicability for the development of a comprehensive mapping and monitoring system of cork oak woodlands in Mediterranean ecosystems. Such techniques are vital to develop a detailed management strategy and to assist restoration activities and the economic assessment of semi-natural habitats. A case study, carried out in two different locations in Calabria (Italy, is provided.

  18. A 548-year long tree-ring chronology of oak (Quercus spp.) for SE Slovenia and its significance as dating tool and climate archive

    OpenAIRE

    De Luis, Martin; Eckstein, Dieter; Zupančič, Martin; Čufar, Katarina

    2015-01-01

    Tree-ring series of oak, from both living trees (Quercus petraea and Q. robur) and historic timbers in SE Slovenia were assembled into a 548-year long regional chronology spanning the period A.D. 1456-2003. It is currently the longest and the most replicated oak chronology in this part of Europe at the transition between Mediterranean, Alpine and continental climatic effects. The chronology correlated significantly with regional and local chronologies up to 700 km apart in Austria, Hungary, S...

  19. Seasonal abundance and biology of sporophagous thrips and notes on other thrips (Insecta, Thysanoptera) on the Mediterranean oak, Quercus rotundifolia L. in Navarra (N Spain)

    OpenAIRE

    Goldarazena, A.; Mound, L. A.

    1999-01-01

    This paperrecords the seasonal abundance of four species of sporophagous thrips collected on the Mediterranean oak, Quercus rotundifolia L., in the Mediterranean area of Navarra (N Spain). The life cycles of Cornpsothrips albosignatus (Reuter), Priesneriella clavicornis (Knechtel); Megalothrips bonannii Uzel and Cryptohrips nigripes (Reuter) are reported, and notes given about habitat specificity and wing development. Notes about host specific Terebrantia thrips of the Mediterranean oak are a...

  20. Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil

    International Nuclear Information System (INIS)

    Fantozzi, Federica; Monaci, Fabrizio; Blanusa, Tijana; Bargagli, Roberto

    2013-01-01

    We investigated the role of urban Holm Oak (Quercus ilex L.) trees as an airborne metal accumulators and metals' environmental fate. Analyses confirmed Pb, Cd, Cu and Zn as a main contaminants in Siena's urban environment; only Pb concentrations decreased significantly compared to earlier surveys. Additionally, we determined chemical composition of tree leaves, litter and topsoil (underneath/outside tree crown) in urban and extra-urban oak stands. Most notably, litter in urban samples collected outside the canopy had significantly lower concentrations of organic matter and higher concentrations of Pb, Cu, Cd and Zn than litter collected underneath the canopy. There was a greater metals' accumulation in topsoil, in samples collected under the tree canopy and especially near the trunk (‘stemflow area’). Thus, in urban ecosystems the Holm Oak stands likely increase the soil capability to bind metals. -- Highlights: ► Of the main metal contaminants only leaf Pb concentrations decreased in the period 1994–2011. ► Leaf Cd, Cr, Cu, Pb and Zn concentrations were higher in urban than in extra urban park. ► In urban park litter, Cu, Cd, Pb and Zn concentrations were higher outside than underneath the tree crown. ► Conversely, in urban park soil, Cu, Cd, Pb and Zn concentrations were lower outside the crown. ► Soil therefore behaves as a sink for metal contaminants such as Cu, Pb and Cd. -- Quercus ilex leaves are efficient interceptors of airborne trace elements in urban environments and we found an increased accumulation of metals in topsoil under the tree canopy

  1. Drivers of radial growth and carbon isotope discrimination of bur oak (Quercus macrocarpa Michx.) across continental gradients in precipitation, vapour pressure deficit and irradiance

    Science.gov (United States)

    Steven L. Voelker; Frederick C. Meinzer; Barbara Lachenbruch; J. Renee Brooks; Richard P. Guyette

    2014-01-01

    Tree-ring characteristics are commonly used to reconstruct climate variables, but divergence from the assumption of a single biophysical control may reduce the accuracy of these reconstructions. Here, we present data from bur oaks (Quercus macrocarpa Michx.) sampled within and beyond the current species bioclimatic envelope to identify the primary...

  2. Does Habitat Matter in an Urbanized Landscape? The Birds of the Garry Oak (Quercus garryana) Ecosystem of Southeastern Vancouver Island, British Columbia

    Science.gov (United States)

    Richard E. Feldman; Pam G. Krannitz

    2005-01-01

    The Garry oak (Quercus garryana) ecosystem was once a dominant habitat type on southeastern Vancouver Island, British Columbia, but urbanization has lead to massive habitat loss and fragmentation (Hebda 1993). Most bird species are expected to respond negatively to urbanization because of increased patch isolation, increased predation pressure, and negative edge...

  3. Genetic structure of a natural oak community in central Italy: Evidence of gene flow between three sympatric white oak species (Quercus, Fagaceae

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    Gaby Antonecchia

    2015-12-01

    Full Text Available Incomplete reproductive barriers between species, especially in sympatric areas where several species coexist, may result in hybridization and an increase in genetic diversity. Here we assessed the amount of genetic diversity in a community of three interfertile and sympatric European oaks (Quercus frainetto Ten., Q. petraea Liebl. Matt. and Q. pubescens Willd. situated in central Italy. We used 11 microsatellite markers derived from Expressed Sequence Tag (EST-SSRs and we implemented a Bayesian clustering analysis to assign individuals to species or hybrids. All genotyped loci were polymorphic for all the species and three genetic clusters corresponding to each species were detected. Significant differences and a higher level of gene flow were observed between the three oak species. Occurrence of hybrids varied markedly within the studied area: hybrids between Q. petraea and Q, pubescens were the most frequent, while hybrids between Q. petraea and Q. frainetto were particularly rare. Q. pubescens and Q. petraea showed the highest number of alleles compared to Q. frainetto,which was characterized by a low number of private, but highly frequent, alleles. However, Q. frainetto showed a lower genetic diversity and a stronger reproductive isolation from the other two oak species.

  4. Tree crown size as a measure of tree biosocial position in 135-year-old oak (Quercus L. stand

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    Kaźmierczak Katarzyna

    2016-03-01

    Full Text Available The paper presents an attempt to apply measurable traits of a tree – crown projection area, crown length, diameter at breast height and tree height for classification of 135-year-old oak (Quercus L. trees into Kraft classes. Statistical multivariate analysis was applied to reach the aim. Empirical material was collected on sample plot area of 0.75 ha, located in 135-year-old oak stand. Analysis of dimensional traits of oaks from 135-year-old stand allows quite certain classification of trees into three groups: pre-dominant, dominant and co-dominant and dominated ones. This seems to be quite promising, providing a tool for the approximation of the biosocial position of tree with no need for assessment in forest. Applied analyses do not allow distinguishing trees belonging to II and III Kraft classes. Unless the eye-estimation-based classification is completed, principal component analysis (PCA method provided simple, provisional solution for grouping trees from 135-year-old stand into three over-mentioned groups. Discriminant analysis gives more precise results compared with PCA. In the analysed stand, the most important traits for the evaluation of biosocial position were diameter at breast height, crown projection area and height.

  5. An analysis of phenotypic selection in natural stands of northern red oak (Quercus rubra L.)

    Science.gov (United States)

    Jeffery W. Stringer; David B. Wagner; Scott E. Schlarbaum; Daniel B. Houston

    1995-01-01

    Comparison of growth and stem quality parameters of 19-year-old progeny from superior and comparison trees indicates that rigorous phenotypic selection of trees in natural stands may not be an efficient method of parent tree selection for Quercus rubra L. Total tree height, dbh, number of branches in the butt log, fork height, and number of mainstem...

  6. Digestion and body weight change in Tuj lambs receiving oak (Quercus hartwissiana) leaves with and without PEG

    Energy Technology Data Exchange (ETDEWEB)

    Yildiz, S. [Department of Physiology, Faculty of Veterinary Sciences, Kafkas University, Kars (Turkey)]. E-mail: yildizsedat@hotmail.com; Kaya, I.; Unal, Y.; Aksu Elmali, D.; Kaya, S.; Oncuer, A. [Department of Animal Nutrition, Faculty of Veterinary Sciences, Kafkas University, Kars (Turkey); Cenesiz, M.; Kaya, M. [Department of Physiology, Faculty of Veterinary Sciences, Kafkas University, Kars (Turkey)

    2005-08-19

    Quercus hartwissiana (oak) leaves are a potential alternative feed resource in the north-east of Turkey. The aim of the current study was to evaluate the effects of two levels (185 and 370 g/day) of dry oak leaves, in the presence (50 or 100 g/kg of dry oak leaves) or absence of polyethylene glycol (PEG 6000), on ruminal fermentation parameters (pH, short-chain fatty acids (SCFA), ammonia nitrogen (NH{sub 3}-N)), microbial nitrogen (N) supply, apparent diet digestibility, N retention, and body weight (BW) change in fat-tailed Tuj lambs (n = 42, initial BW 33.0 {+-} 0.7 kg). The lambs received at random one of the following diets for 60 days (on a dry matter basis, n = 6 per group): (1) control, no oak leaves and no PEG; (2) 185 g oak leaves; (3) 185 g oak leaves + 10 g PEG; (4) 185 g oak leaves + 20 g PEG; (5) 370 g oak leaves; (6) 370 g oak leaves + 20 g PEG; (7) 370 g oak leaves + 40 g PEG. All groups were given 272 g concentrate and varying amounts of hay (a mixture of chopped grass and alfalfa in the ratio 55:45), such that the amount of hay plus oak leaves was equal to 645 g. Ruminal fermentation parameters did not change with treatment (pH 6.50 {+-} 0.02, total SCFA 86.3 {+-} 2.1 mmol/L, NH{sub 3}-N = 207 {+-} 5 mg/L). Total CP digestibility (0.775, 0.714, 0.736, 0.748, 0.663, 0.690, 0.672; S.E.M. = 0.008, P < 0.001, for groups 1-7, respectively) and N retention (7.7, 6.8, 6.7, 7.5, 6.1, 5.8, 5.7 g/day; S.E.M. = 0.19, P < 0.05, for groups 1-7, respectively) were lowest but microbial N supply was highest in 370 g oak leaf group supplemented with PEG (6.51, 7.14, 11.45, 12.23, 9.03, 14.49, 14.39 g/day, S.E.M. = 0.76, P < 0.05, for groups 1-7, respectively). Final BW (32.5 {+-} 0.3 kg) did not differ among treatments (P > 0.05). These data suggest that: (1) PEG addition seems unnecessary as it did not improve CP digestibility, N retention and BW; and (2) Q. hartwissiana leaves may be used to replace at least half of hay in the ration of Tuj lambs without a

  7. Can prescribed fires be used to promote the recruitment of white oak (Quercus alba) seedlings?

    Science.gov (United States)

    G. Geoff Wang; David H. Van Lear; William L. Bauerie

    2006-01-01

    Widespread oak replacement by mesophytic tree species, especially on good quality sites, has been occurring across the Eastern United States, because advance oak reproduction is severely limited by the development of heavy midstory and understory. Anecdotal evidence suggests that the development of heavy midstory and understory coincides with the implementation of a...

  8. Post-planting treatments increase growth of Oregon white oak (Quercus garryana Dougl. ex Hook.) seedlings.

    Science.gov (United States)

    W.D. Devine; C.A. Harrington; L.P. Leonard

    2007-01-01

    The extent of Oregon white oak woodland and savanna ecosystems in the Pacific Northwest has diminished significantly during the past century, and planting of Oregon white oak seedlings is often necessary for restoring these plant communities. Our objective was to evaluate the effects of tree shelters, control of competing vegetation, fertilization, irrigation, and...

  9. Stem-quality of sessile oak (Quercus petraea (Matt. Liebl. trees, Tuscany, Italy

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    Grifoni F

    2007-01-01

    Full Text Available The Regional Forest Inventory reports a significant presence of sessile oak in Tuscany. The noticeable increase of sessile oak timber value in better-shaped stems, suggests the advance evaluation of the quality of standing trees. In this way, the consistency of the applied silvicultural rules may be verified, too. The research trial was undertaken in a stand aged 41 to 45 originated from reafforestation a few hectares wide, located at Monte Lignano (Arezzo. The stand structure is not homogeneous as for tree size and tree species composition. Qualitative field surveys were carried out into three well-discernible stand types within the reforested area: a scattered sessile oak trees into a withered chestnut orchard; b pure sessile oak stands; c scattered sessile oak trees into a poor chestnut coppice. Data collected at about one half of the foreseen stand life span showed the different stem quality into each structure and type. In addition, a diffuse growth of epicormic branches along sessile oak stems was observed into pure stands (b, following main crop thinnings and subordinate layer exploitation. This practice consisted therefore in a worsening of oak stems quality. As already showed by the practice of silviculture into sessile oak stands across Europe, these results proved that the production of valuable stems needs suited and well-timed tending practices.

  10. Conservation and fruit biology of Sichou oak (Quercus sichourensis, Fagaceae – A critically endangered species in China

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    Ke Xia

    2016-10-01

    Full Text Available Several conservation programs have been started for the critically endangered Sichou oak (Quercus sichourensis since 2007. These programs include detailed field investigations, seedling cultivation and research on the fruit biology of the species. In this study, we first report on the five mature individual trees found in our 9-year field investigation. Thus far, a total of 10 mature individuals have been recorded. All Q. sichourensis trees are healthy and most produce healthy acorns. Acorns of Q. sichourensis are large with dry masses of 8.0–14.0 g. These acorns had high moisture contents at collection and died shortly after (7–28 d when dried with silica gel. Characteristics of Q. sichourensis acorns varied between populations. Compared with the acorns from Funing, the acorns collected from Ceheng were bigger, more viable (germination percentage was up to 96%, less sensitive to desiccation, and germinated faster. Q. sichourensis occurs in regions with a distinct 5–6 month dry season. Habitat degradation is largely responsible for the rareness of Quercus sichorensis, but desiccation sensitivity of the acorns may also limit the regeneration of the species and potentially lead to its continued rareness. As a species with extremely small populations (PSESP, Q. sichourensis is facing high risk of extinction and should be defined as a Critically Endangered species in the global IUCN Red List.

  11. The roles of dispersal, fecundity, and predation in the population persistence of an oak (Quercus engelmannii) under global change.

    Science.gov (United States)

    Conlisk, Erin; Lawson, Dawn; Syphard, Alexandra D; Franklin, Janet; Flint, Lorraine; Flint, Alan; Regan, Helen M

    2012-01-01

    A species' response to climate change depends on the interaction of biotic and abiotic factors that define future habitat suitability and species' ability to migrate or adapt. The interactive effects of processes such as fire, dispersal, and predation have not been thoroughly addressed in the climate change literature. Our objective was to examine how life history traits, short-term global change perturbations, and long-term climate change interact to affect the likely persistence of an oak species--Quercus engelmannii (Engelmann oak). Specifically, we combined dynamic species distribution models, which predict suitable habitat, with stochastic, stage-based metapopulation models, which project population trajectories, to evaluate the effects of three global change factors--climate change, land use change, and altered fire frequency--emphasizing the roles of dispersal and seed predation. Our model predicted dramatic reduction in Q. engelmannii abundance, especially under drier climates and increased fire frequency. When masting lowers seed predation rates, decreased masting frequency leads to large abundance decreases. Current rates of dispersal are not likely to prevent these effects, although increased dispersal could mitigate population declines. The results suggest that habitat suitability predictions by themselves may under-estimate the impact of climate change for other species and locations.

  12. The roles of dispersal, fecundity, and predation in the population persistence of an oak (Quercus engelmannii under global change.

    Directory of Open Access Journals (Sweden)

    Erin Conlisk

    Full Text Available A species' response to climate change depends on the interaction of biotic and abiotic factors that define future habitat suitability and species' ability to migrate or adapt. The interactive effects of processes such as fire, dispersal, and predation have not been thoroughly addressed in the climate change literature. Our objective was to examine how life history traits, short-term global change perturbations, and long-term climate change interact to affect the likely persistence of an oak species--Quercus engelmannii (Engelmann oak. Specifically, we combined dynamic species distribution models, which predict suitable habitat, with stochastic, stage-based metapopulation models, which project population trajectories, to evaluate the effects of three global change factors--climate change, land use change, and altered fire frequency--emphasizing the roles of dispersal and seed predation. Our model predicted dramatic reduction in Q. engelmannii abundance, especially under drier climates and increased fire frequency. When masting lowers seed predation rates, decreased masting frequency leads to large abundance decreases. Current rates of dispersal are not likely to prevent these effects, although increased dispersal could mitigate population declines. The results suggest that habitat suitability predictions by themselves may under-estimate the impact of climate change for other species and locations.

  13. Restoration of Black Oak (Quercus velutina) Sand Barrens via Three Different Habitat Management Approaches

    Science.gov (United States)

    Kriska, David John

    Disturbance regimes, i.e. frequent fires, historically maintained oak barrens until European settlement patterns, and eventually, Smoky the Bear and the fire suppression campaign of the U.S. Forest Service snuffed out the periodic flames. In the absence of a disturbance regime, ground layer floral composition at many historical oak sand barrens will change predominantly because of a buildup of leaf litter and shading of the soils. Termed mesophication, this process of ecological succession will drive Black Oak Sand Barrens to an alternate steady state. A survey conducted on Singer Lake Bog in Green, Ohio, demonstrated that succession shifted the community to red maple-black cherry woodlands more typical of a dry southern forest. In an attempt to revive disturbance, three restoration techniques were applied at ten degraded northeast Ohio oak barrens to contrast their effectiveness in restoring black oak sand barren flora. The three restoration treatments were select canopy tree reduction favoring 5% to 30% tree canopy cover, forest floor leaf litter removal, and prescribed fire. Vegetation responses to manipulations were monitored prior to and following treatment applications, and were compared against both baseline data from before-treatment surveys and paired control sites adjacent treated areas. Imposing disturbance successfully increased species diversity and abundance above that found across Singer Lake Bog compared to sampling made prior to and adjacent to treated areas. Select canopy tree removal exhibited the largest floral responses from targeted barrens species, i.e. graminoids. A forest floor invertebrate family (Carabidea: Coleoptera) was measured for species richness and abundance pre and post treatment, where a noticeable shift occurred away from woodland obligate ground beetles toward open grassland species. Replicating oak barren structure, prior to replicating disturbance processes, is the first step in the ecological restoration of these systems.

  14. Overstory density affects field performance of underplanted red oak (Quercus rubra L.) in Ontario

    Science.gov (United States)

    Daniel C. Dey; William C. Parker

    1997-01-01

    Red oak seedlings were underplanted in a closed-canopy mature northern hardwood stand and an adjacent shelterwood in central Ontario. Overstory density effects on seedling survival and growth were assessed 2 yr after planting. After 2 yr, seedling survival was 90% in the uncut stand and over 99% in the shelterwood. Seedlings in the uncut stand experienced negligible or...

  15. Environmental relationships of native Garry oak (Quercus garryana) communities at their northern migration

    Science.gov (United States)

    Wayne R. Erickson

    2002-01-01

    Knowledge of relationships among plant communities and environmental variables can be used in restoration, ecological assessments, predictive mapping and conservation planning. This information would be particularly important in the conservation of endangered ecosystems, such as those of Garry oak in British Columbia. To investigate relationships, sixteen environmental...

  16. A method to quantify infection and colonization of holm oak (Quercus ilex) roots by Phytophthora cinnamomi.

    Science.gov (United States)

    Ruiz-Gómez, Francisco J; Sánchez-Cuesta, Rafael; Navarro-Cerrillo, Rafael M; Pérez-de-Luque, Alejandro

    2012-09-13

    Phytophthora cinnamomi Rands. is an important root rot pathogen widely distributed in the north hemisphere, with a large host range. Among others diseases, it is known to be a principal factor in the decline of holm oak and cork oak, the most important tree species in the "dehesa" ecosystem of south-western Spain. Previously, the focus of studies on P. cinnamomi and holm oak have been on molecular tools for identification, functional responses of the host, together with other physiological and morphological host variables. However, a microscopic index to describe the degree of infection and colonization in the plant tissues has not yet been developed. A colonization or infection index would be a useful tool for studies that examine differences between individuals subjected to different treatments or to individuals belonging to different breeding accessions, together with their specific responses to the pathogen. This work presents a methodology based on the capture and digital treatment of microscopic images, using simple and accessible software, together with a range of variables that quantify the infection and colonization process.

  17. A method to quantify infection and colonization of holm oak (Quercus ilex roots by Phytophthora cinnamomi

    Directory of Open Access Journals (Sweden)

    Ruiz-Gómez Francisco J

    2012-09-01

    Full Text Available Abstract Phytophthora cinnamomi Rands. is an important root rot pathogen widely distributed in the north hemisphere, with a large host range. Among others diseases, it is known to be a principal factor in the decline of holm oak and cork oak, the most important tree species in the “dehesa” ecosystem of south-western Spain. Previously, the focus of studies on P. cinnamomi and holm oak have been on molecular tools for identification, functional responses of the host, together with other physiological and morphological host variables. However, a microscopic index to describe the degree of infection and colonization in the plant tissues has not yet been developed. A colonization or infection index would be a useful tool for studies that examine differences between individuals subjected to different treatments or to individuals belonging to different breeding accessions, together with their specific responses to the pathogen. This work presents a methodology based on the capture and digital treatment of microscopic images, using simple and accessible software, together with a range of variables that quantify the infection and colonization process.

  18. Oak Woodland Artificial Regeneration - Correlating Soil Moisture to Seedling Survival

    Science.gov (United States)

    Tim R. Plumb; Karl Kraus

    1991-01-01

    The primary goal of this study was to find economical and effective planting techniques that will ensure the establishment and early survival of coast live oak (Quercus agrifolia Née) and blue oak (Q. douglasii H. and A.) in the Central Coast region of California. Eight treatments were evaluated ranging from unprotected seed spots...

  19. Seed production timing influences seedling fitness in the tropical live oak Quercus oleoides of Costa Rican dry forests.

    Science.gov (United States)

    Center, Alyson; Etterson, Julie R; Deacon, Nicholas John; Cavender-Bares, Jeannine

    2016-08-01

    Reproductive phenology is important for tree species that occur in seasonally dry environments, particularly for those with desiccation-sensitive, nondormant seeds. In this study, we compared germination, growth, and survival of seeds of the evergreen tropical live oak Quercus oleoides produced at different times during the wet season at two sites that differ in rainfall along an elevation gradient. Our goal was to determine the effects of reproductive timing on germination and juvenile fitness for this widespread species in seasonally dry forests of northwestern Costa Rica. We collected seeds early and late in a single wet season from two populations with contrasting rainfall and reciprocally planted them into common gardens. Two watering treatments (ambient and supplemental watering) were established at the drier low-elevation garden. Seeds were exposed to ambient rainfall at the wetter high-elevation garden. We conducted selection analyses using aster models to examine variation in selection on seed size and timing of germination. Trees of Q. oleoides had higher fitness when seeds were produced, dispersed and germinated late in the wet season. Postgermination, water limitation during the dry season reduced seedling fitness by decreasing survival but not growth. In contrast to studies in temperate climates where earlier germination is typically favored, we show that selection on days to germination is temporally and spatially heterogeneous. Selection was found to favor either rapid or delayed germination depending on seed cohort and habitat. © 2016 Botanical Society of America.

  20. Exploring Growth Variability and Crown Vitality of Sessile Oak (Quercus petraea) in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Rybníček, Michal; Čermák, P.; Žid, T.; Kolář, Tomáš; Trnka, Miroslav; Büntgen, Ulf

    2015-01-01

    Roč. 42, č. 1 (2015), s. 17-27 ISSN 1733-8387 R&D Projects: GA MŠk(CZ) EE2.4.31.0056; GA MŠk(CZ) EE2.3.20.0248; GA MŠk(CZ) EE2.3.20.0265; GA ČR GA13-04291S Institutional support: RVO:67179843 Keywords : Central Europe * crown condition * precipitation * sessile oak * temperature * tree rings Subject RIV: GK - Forestry Impact factor: 0.723, year: 2014

  1. Response of two populations of holm oak (Quercus rotundifolia Lam.) to sulfur dioxide.

    Science.gov (United States)

    García, D; Rodríguez, J; Sanz, J M; Merino, J

    1998-01-01

    Experiments were carried out with seedlings of Quercus rotundifolia Lam., an evergreen schlerophyllous tree typical of the Spanish Mediterranean climate environments. Fruits were collected in two distant (800 km) populations located in the center (southern Spain) and northern border (northern Spain) of the area of distribution of the species. One-month-old potted plants were grown for 130 days in an enriched atmosphere of SO2 (0.23 ppm, 14 h/day) in controlled (growth chamber) conditions. Both northern and southern plants underwent a significant decrease in growth rate as a consequence of the treatment. Even so, plants appear to be quite resistant to SO2 compared with either more temperate or more productive species. The southern population was more sensitive to the treatment, as reflected by the bigger decrease in both growth and photosynthetic rates. Differences in resistance appear to be related to the biogeographic origin of the populations studied, which underlines the importance of biogeographic aspects in studies of resistance to air pollutants.

  2. Decline in holm oak coppices (Quercus ilex L. subsp. ballota (Desf.) Samp.): biometric and physiological interpretations

    Energy Technology Data Exchange (ETDEWEB)

    Serrada, R.; Gómez-Sanz, V.; Aroca, M.J.; Otero, J.; Bravo-Fernández, J.A.; Roig, S.

    2017-11-01

    Aim of the study: To analyse the decline in aged holm oak coppice forests as regards above-ground and below-ground fractions and physiological features. Area of study: Centre of the Iberian Peninsula (Guadalajara province). Material and methods: 26 pairs of holm oak stools with different vigour but with similar site and structural characteristics within each pair were selected. Morphological (basal area, number of stools, maximum height) and physiological traits (leaf water potential, stomatal conductance) of the standing stools were assessed. Their aerial and underground parts were extracted and different size fractions of both their above and below-ground biomass were quantified. Linear mixed models were built to test the effect of ’Stool vigour’ on the mean behaviour of the measured variables. Additionally, for the aerial part, linear regressions between the weights of the different size fractions and the basal area at breast height were performed using ‘Stool vigour’ as a fixed factor. Main results: For the same site, root depth, and number and diameter of shoots than good vigour stools, poor vigour stools displayed: lower predawn water potential, greater leaf mass per unit of area; lower total leaf area; lower above-ground biomass (in total as well as per fractions); lower fine roots biomass; lower proportion of leaf biomass and a greater proportion of biomass of both all roots and those with diameter 2-7 cm. Research highlights: The above-ground physiological and morphological characteristics of declined stools are interpreted as poorer adaptation to site conditions. Root system architecture was found to be relevant to explain this behaviour.

  3. Investigation of the Amount of Tannic Acid in Bark Oak (Quercus castanifolia

    Directory of Open Access Journals (Sweden)

    Shayesteh Jahanshahi

    2011-01-01

    Full Text Available In order to perform a qualitative and quantitative investigation on tannic acid content in Oak bark, the bark samples were collected from Educational Forest of Gorgan Agricatural Science and Natural Resources University. Solvents were used in laboratory to extract tannin and were considered as variables. Regarding diversity of bark components, Tappi Test Method (T264-om-88 was used to determin extractives contest. Twenty grams dry material was placed in a soxhelt. Extracted material with hot water, methanol and water- methanol (1:1 solvent were 25±2, 20±2 and 18±2 percents respectively. Tannic acid existance in extracts was determined using High Performance Liquid Choromatography (HPLC and types of bonds were determined using FT-IR. Results showed that water-methanol solvent was the best solvent for extracting tannin.the amount of extracted tannic acid in maximum wavelength of 250 nm and using gradient system, in solvent water-methanol, methanol and hot water solvent were 70±2, 30±2 and 5±2 precents, respectively. Amount of tannin in the bark using solvent water-methanol was determined to be 14 perecents that was the highest amount.

  4. Growth-Climate Response of Young Turkey Oak (Quercus cerris L. Coppice Forest Stands along Longitudinal Gradient in Albania

    Directory of Open Access Journals (Sweden)

    Merita Stafasani

    2015-06-01

    Full Text Available Background and Purpose: Turkey oak (Quercus cerris L. is the most widespread species in Albania and less investigated from dendroclimatological point of view. Previous studies have reported that Q. cerris is sensitive to the environment when growing at different latitudes and ecological conditions. Based on this fact we have explored the response of different Q. cerris populations located along the longitudinal gradient. Materials and Methods: The stem discs were sampled from six sites (Kukes, Diber, Rreshen, Ulez, Elbasan, Belsh along longitudinal gradient ranging from north-east to central Albania. All oak forests stands grow under the influence of specific local Mediterranean climate. Tree-ring widths were measured to the nearest 0.001 mm using a linear table, LINTAB and the TSAP-Win program. Following the standard dendrochronological procedures residual tree-ring width chronologies were built for each site. Statistical parameters commonly used in dendrochronology were calculated for each site chronology. Relations between the tree-ring chronologies were explored using Hierarchical Factor Classification (HFC and Principal Component Analysis (PCA, while the radial growth-climate relationship was analyzed through correlation analysis using a 19-month window from April in the year prior to tree-ring formation (year t - 1 until October in the year of growth (year t. Results and Conclusions: The length of the site chronologies ranged from 16 to 36 years, with the Elbasan site chronology being the longest and the Belsh site chronology the shortest one. Trees at lower elevation were younger than trees at higher elevation. Statistical parameters (mean sensitivity (MS and auto correlation (AC of site chronologies were different among them and lower values of AC1 showed a weaker dependence of radial growth from climatic conditions of the previous growing year. Principal component analysis showed that Belsh, Rreshen and Elbasan site chronologies were

  5. Spatiotemporal variation in acorn production and damage in a Spanish holm oak (Quercus ilex) dehesa

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Izquierdo, L.; Pulido, F.

    2013-05-01

    Aim of study. There is a lack of knowledge about spatio-temporal patterns of acorn production in dehesas, especially regarding the influence of different agents causing acorn damage. We examined the spatial and temporal variability on acorn production and damage in four stands within a dehesa farm in 1997, 1998 and 1999. Area of study. The study was carried out in a 1800 ha dehesa farm of Caceres province, western Spain. Material and Methods. Acorns were sampled by means of seed traps placed in the canopy of six holm oak trees per stand. Acorn collected in it were counted and assessed for damage by Curculio weevils, Cydia moths and the bacterial pathogen Brenneria quercina. Main results. Mean acorn production for the whole study period was 44.60 acorns m-2, which did not vary significantly either among stands or among years. The variability among individual trees was very high (0-300 acorns m{sup -}2). The rate of infestation by Curculio was 7.64 {+-} 10.72 %, by Cydia was 1.76 {+-}3.33 %, whereas 10.29 {+-} 16.12 % of acorns were infested by Brenneria. We found no significant spatial differences, but the rates of acorn loss by insects varied among years. These rates were independent of annual acorn production and there was no correlation among damages by different pests, except between Curculio and Cydia in two crop years. Research highlights. It can be concluded that acorn crops are synchronized at the within-farm level and that the temporal variation in acorn damages can be independent of crop size. (Author) 49 refs.

  6. Variation of Oriental Oak (Quercus variabilis Leaf δ13C across Temperate and Subtropical China: Spatial Patterns and Sensitivity to Precipitation

    Directory of Open Access Journals (Sweden)

    Baoming Du

    2015-06-01

    Full Text Available The concentration of the carbon-13 isotope (leaf δ13C in leaves is negatively correlated with the mean annual precipitation (MAP atlarge geographical scales. In this paper, we explain the spatial pattern of leaf δ13C variation for deciduous oriental oak (Quercus variabilis Bl. across temperate and subtropical biomes and its sensitivity to climate factors such as MAP. There was a 6‰ variation in the leaf δ13C values of oak with a significant positive correlation with latitude and negative correlations with the mean annual temperature (MAT and MAP. There was no correlation between leaf δ13C and altitude or longitude. Stepwise multiple regression analyses showed that leaf δ13C decreased 0.3‰ per 100 mm increase in MAP. MAP alone could account for 68% of the observed variation in leaf δ13C. These results can be used to improve predictions for plant responses to climate change and particularly lower rainfall.

  7. Population-Level Differentiation in Growth Rates and Leaf Traits in Seedlings of the Neotropical Live Oak Quercus oleoides Grown under Natural and Manipulated Precipitation Regimes

    Directory of Open Access Journals (Sweden)

    Jose A. Ramírez-Valiente

    2017-05-01

    Full Text Available Widely distributed species are normally subjected to spatial heterogeneity in environmental conditions. In sessile organisms like plants, adaptive evolution and phenotypic plasticity of key functional traits are the main mechanisms through which species can respond to environmental heterogeneity and climate change. While extended research has been carried out in temperate species in this regard, there is still limited knowledge as to how species from seasonally-dry tropical climates respond to spatial and temporal variation in environmental conditions. In fact, studies of intraspecific genetically-based differences in functional traits are still largely unknown and studies in these ecosystems have largely focused on in situ comparisons where environmental and genetic effects cannot be differentiated. In this study, we tested for ecotypic differentiation and phenotypic plasticity in leaf economics spectrum (LES traits, water use efficiency and growth rates under natural and manipulated precipitation regimes in a common garden experiment where seedlings of eight populations of the neotropical live oak Quercus oleoides were established. We also examined the extent to which intraspecific trait variation was associated with plant performance under different water availability. Similar to interspecific patterns among seasonally-dry tropical tree species, live oak populations with long and severe dry seasons had higher leaf nitrogen content and growth rates than mesic populations, which is consistent with a “fast” resource-acquisition strategy aimed to maximize carbon uptake during the wet season. Specific leaf area (SLA was the best predictor of plant performance, but contrary to expectations, it was negatively associated with relative and absolute growth rates. This observation was partially explained by the negative association between SLA and area-based photosynthetic rates, which is contrary to LES expectations but similar to other recent

  8. Ultraviolet-B radiation influences the abundance and distribution of phylloplane fungi on pedunculate oak (Quercus robur)

    International Nuclear Information System (INIS)

    Newsham, K.K.; Low, M.N.R.; McLeod, A.R.; Greenslade, P.D.; Emmett, B.A.

    1997-01-01

    The effects of u.v.-B radiation (280-315 nm) on the fungi occurring on the lammas leaves of pedunculate oak (Quercus robur L.) were examined using saplings that were exposed at an outdoor facility to supplemental levels of u.v.-B radiation under treatment arrays of cellulose diacetate-filtered fluorescent lamps, which also produce u.v.-A radiation (315-400 nm). Saplings were also exposed to u.v.-A radiation alone under control arrays of polyester-filtered lamps, and to ambient levels of solar radiation under arrays of unenergized lamps. The u.v.-B treatment corresponded to a 30% elevation above the ambient level of erythemally-weighted u.v.-B radiation. The fungi were examined weekly over a 4-month-period in summer and autumn 1995 using two techniques, the spore fall and leaf impression methods, which differentiated between those fungi occurring on the upper (adaxial) and lower (abaxial) surfaces of the leaves. The abundances of Aureobasidium pullulans (De Bary) Arnaud and Sporobolomyces roseus Kluy. et van Niel, two leaf yeasts which had adaxial:abaxial ratios of < 1 under ambient levels of u.v.-B radiation, were negatively correlated with increasing ambient levels of u.v.-B radiation and were significantly reduced on adaxial leaf surfaces by supplemental levels of u.v.-B. There were few effects of supplemental u.v.-B radiation on the abundances of these yeasts on abaxial leaf surfaces. The abundances of the dematiaceous hyphomycetes, Cladosporium spp. and Epicoccum nigrum Link., species with adaxial:abaxial ratios of ⩾ 1 under ambient levels of u.v.-B radiation, were not correlated with ambient levels of u.v.-B radiation, nor were they usually affected on either leaf surface by supplemental u.v.-B radiation. Alternaria spp. and Microdochium nivale (Fr.) Samuels & Hallet showed consistent responses on adaxial leaf surfaces to u.v.-A radiation applied under control and treatment arrays. Our results suggest that current levels of shortwave radiation already

  9. Use of forest species associated to oak forests (Quercus humboldtii Bonpl.) for energetic purposes, in three villages of the Encino municipality in Santander

    International Nuclear Information System (INIS)

    Diaz Silva, Monica Rocio de las Mercedes

    2010-01-01

    We surveyed the firewood consumption for energetic purposes from the oak forest of the Patios Altos and Canada villages in Encino-Santander. Tools used to collect data were: structured surveys, open interviews and participant observation to those families dependent upon forest resources. Twenty-one species for domestic use were recorded, from which seven were related to the oak for est. The most preferred and used tree species was the Oak (Quercus humboldtii Bonpl) followed by the Laurel (Morella pubescens (Humb. and Bonpl. ex Willd.) Wilbur). Results show that 98% of the population uses only firewood and firewood alternated with gas, which suggests the importance of firewood to the community. Firewood consumption per person is 3.6 + - 1.35 kg per day, while annual consumption of the whole group (54 families) is the 354.78 kg per year. This usage corresponds to native tree species (78.2%), native shrubs 12.4%) and exotics (9.3%). Firewood usage represents savings to local inhabitants, corresponding to 33% of their monthly earnings, approximate Oak forest, Colombia, wood demand, native forest species, firewood, domestic use of wood.

  10. An investigation on forage yield capacity of kermes oak (Quercus coccifera L.) and grazing planning of Mediterranean maquis scrublands for traditional goat farming.

    Science.gov (United States)

    Tolunay, Ahmet; Adıyaman, Elif; Akyol, Ayhan; İnce, Duygu; Türkoğlu, Türkay; Ayhan, Veysel

    2014-01-01

    This study investigated grazing capacities of maquis scrubland and preparation principles of grazing management in forest resources. Kermes oak (Quercus coccifera L.), which is widespread as a main shrub species in maquis vegetation in Turkey, and pure hair goats (Capra hircus L.) feeding on shoots and leaves of this shrub were selected for study. The study was conducted in two stages. Green leaf and shoot samples were taken from kermes oaks in the first stage and the amount of green herbage yield (g ∗ m(-1)) and dry matter yield (kg ∗ ha(-1)) that may be obtained per unit area from these samples was identified. The considered amount of dry matter consumed by pure hair goats daily and the number of goats being fed within 1 year on land of 1 ha according to different land coverage rates of kermes oaks (goat head ∗ ha ∗ yr) were calculated. In the second stage, grazing capacities of sample areas where kermes oak spread were identified and compared with the grazing plan prepared by the forestry administration for this area. Forage yield variance according to land coverage rates of maquis scrublands should be considered when determining optimum animal numbers for grazing per area for sustainable goat farming.

  11. Photosynthesis and water relations of the mistletoe, Phoradendron villosum, and its host, the California valley oak, Quercus lobata

    Science.gov (United States)

    David Y. Hollinger

    1983-01-01

    Water vapor and CO2 exchange characteristics were studied in Phoradendron villosum, a hemiparasitic mistletoe and its host, Quercus lobata. The hemiparasite had stomatal conductances equal to or higher than the host but a much lower capacity to fix carbon. Respiration was high in the mistletoe relative to...

  12. Phenotypic variation in California populations of valley oak (Quercus lobata Née) sampled along elevational gradients

    Science.gov (United States)

    Ana L. Albarrán-Lara; Jessica W. Wright; Paul F. Gugger; Annette Delfino-Mix; Juan Manuel Peñaloza-Ramírez; Victoria L. Sork

    2015-01-01

    California oaks exhibit tremendous phenotypic variation throughout their range. This variation reflects phenotypic plasticity in tree response to local environmental conditions as well as genetic differences underlying those phenotypes. In this study, we analyze phenotypic variation in leaf traits for valley oak adults sampled along three elevational transects and in...

  13. The Response of Basal Area Increment in Old Sprout-origin Sessile Oak (Quercus petraea (Matt. Liebl. Trees During Their Conversion to a Coppice-with-standards

    Directory of Open Access Journals (Sweden)

    Zdeněk Adamec

    2014-01-01

    Full Text Available This paper addresses the response of adult sprout-origin sessile oaks (Quercus petraea (Matt. Liebl. to a strong release. Our research plot was established at the Training Forest Enterprise of Mendel University in Brno (Czech Republic at the turn of 2008/2009. The plot is situated on a plateau with mesotrofic soil in a beech-oak forest vegetation zone at an altitude of 410 m above sea level. Tree responses were monitored using precise girth measurements. During the first year after the release, the basal area increment showed a positive correlation with only the tree diameter. During the second and third year, the basal area increment was also correlated with the release intensity. During the third year, the basal area increment was explained by the tree diameter, the crown shape, and the release intensity as well as individual types of epicormic shoot occurrence. The occurrence of epicormic shoots in the lower part of the trunks and umbel-shaped crowns increased the basal area increment. In the first, second and third year after thinning, the model explained 11.79%, 11.25% and 28.99%, respectively, of the basal area increment variability. Adult trees of sprout origin responded to a strong release very early (within two years after felling.

  14. Biomass, Carbon and Nutrient Storage in a 30-Year-Old Chinese Cork Oak (Quercus Variabilis Forest on the South Slope of the Qinling Mountains, China

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    Yang Cao

    2015-04-01

    Full Text Available Chinese cork oak (Quercus variabilis forests are protected on a large-scale under the Natural Forest Protection (NFP program in China to improve the ecological environment. However, information about carbon (C storage to increase C sequestration and sustainable management is lacking. Biomass, C, nitrogen (N and phosphorus (P storage of trees, shrubs, herb, litter and soil (0–100 cm were determined from destructive tree sampling and plot level investigation in approximately 30-year old Chinese cork oak forests on the south slope of the Qinling Mountains. There was no significant difference in tree components’ biomass estimation, with the exception of roots, among the available allometric equations developed from this study site and other previous study sites. Leaves had the highest C, N and P concentrations among tree components and stems were the major compartments for tree biomass, C, N and P storage. In contrast to finding no difference in N concentrations along the whole soil profile, higher C and P concentrations were observed in the upper 0–10 cm of soil than in the deeper soil layers. The ecosystem C, N, and P storage was 163.76, 18.54 and 2.50 t ha−1, respectively. Soil (0–100 cm contained the largest amount of C, N and P storage, accounting for 61.76%, 92.78% and 99.72% of the total ecosystem, followed by 36.14%, 6.03% and 0.23% for trees, and 2.10%, 1.19% and 0.03% for shrubs, herbs and litter, respectively. The equations accurately estimate ecosystem biomass, and the knowledge of the distribution of C, N and P storage will contribute to increased C sequestration and sustainable management of Chinese cork oak forests under the NFP program.

  15. Differences in photosynthesis and isoprene emission in post oak (Quercus stellata) and sweetgum (Liquidambar styraciflua) trees along an urban-to-rural gradient in Texas

    Science.gov (United States)

    Crossett, C.; Lahr, E.; Haas, G.; Schade, G. W.

    2014-12-01

    Many plants produce isoprene, a volatile organic compound that can mitigate damage to photosynthetic systems during short- or long-term increases in leaf temperature. After its production within leaves, isoprene is emitted to the atmosphere and influences regional atmospheric chemistry. Here, we use an urban-to-rural gradient to explore future effects of climate change on tree eco-physiology and feedbacks to atmospheric chemistry. Urban areas mimic many of the conditions expected to occur in the future; in particular, cities have warmer temperatures due to the urban heat island (UHI) effect, and less water availability relative to rural areas. Along a 90 km urban-to-rural gradient, we measured photosynthesis and isoprene emission from trees at three sites in eastern Texas: Houston (urban), The Woodlands (suburban) and Sam Houston National Forest (rural). Isoprene emission from post oak (Quercus stellata) was higher in Houston than the other sites, and when leaf temperatures were increased above ambient conditions, trees produced more isoprene. Leaves produced more isoprene at high leaf temperatures in early summer than in late summer, suggesting gradual acclimation of photosynthetic processes over the course of the summer. We also found that sweetgum (Liquidambar styraciflua) emitted more isoprene than post oak, but when leaf temperatures were increased, isoprene emission was exhausted more quickly in sweetgum relative to post oak. At the same time, post oak maintained higher levels of photosynthesis seasonally and during short-term temperature increases. Both post oak and sweetgum are significant isoprene emitters and represent approximately two and four percent crown cover in the United States, respectively. Our results suggest that in a warming climate, we can expect trees to produce more isoprene seasonally and in response to short-term temperature extremes, and that species-specific differences in photosynthesis and isoprene emission may play an important role

  16. Establishment limitation of holm oak (Quercus ilex subsp ballota (Desf.) Samp.) in a Mediterranean savanna - forest ecosystem

    NARCIS (Netherlands)

    Smit, Christian; Diaz, Mario; Jansen, Patrick

    2009-01-01

    Tree recruitment in Mediterranean savannas is generally hampered, in contrast with the original oak forests where these savannas are derived from. We asked whether this difference in recruitment success can be explained by differential post-dispersal survival. For one year we monitored

  17. Evaluation of the degree of healthiness of the pedunculate oak (Quercus robur L. acorns in the Włoszczowa– Jędrzejów Nature Park and its neighbouring area

    Directory of Open Access Journals (Sweden)

    Bąk-Badowska Jolanta

    2017-03-01

    Full Text Available The aim of the study was to demonstrate the degree of healthiness of the pedunculate oak (Quercus robur acorns found in the Włoszczowa-Jędrzejów Nature Park (abbreviation: W-JOChK and in the neighbouring area. It was dealt with by making the analysis of health of the acorns (total 3,600. The research material included the samples of fallen down acorns, collected under the pedunculate oaks in Kurzelów (W-JOChK, as well as Żelisławice. The study was conducted from late September 2014 to early October 2015.

  18. Influence of weather at time of pollenation on acorn production of Quercus alba and Quercus velutina

    Science.gov (United States)

    Robert A. Cecich; Neal H. Sullivan

    1999-01-01

    Pistillate flower development and acorn production were observed in small populations of white oak (Quercus alba L.) and black oak (Quercus velurina Lam.) in central Missouri from 1990 to 1997. There were significant year-year differences in the size of flower crops for both species and significant tree-tree differences in black...

  19. Oak (Quercus spp.) response to climate differs more among sites than among species in central Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Rybníček, Michal; Čermák, P.; Prokop, O.; Žid, T.; Trnka, Miroslav; Kolář, Tomáš

    2016-01-01

    Roč. 75, jan (2016), s. 55-65 ISSN 1641-1307 R&D Projects: GA MŠk(CZ) LO1415; GA MŠk(CZ) LD13030; GA MŠk(CZ) EE2.3.20.0265; GA ČR GA13-04291S Institutional support: RVO:67179843 Keywords : Central Europe * oak * precipitation * temperature * tree rings Subject RIV: EH - Ecology, Behaviour Impact factor: 0.776, year: 2016

  20. Application of Nearest Neighbor Indices in Persian Oak (Quercus brantii var. persica Coppice Stands of Zagros Forests

    Directory of Open Access Journals (Sweden)

    Y. Erfanifard

    2014-03-01

    Full Text Available The ecological relationship between trees is important in the sustainable management of forests. Studying this relationship in spatial ecology, different indices are applied that are based on distance to nearest neighbor. The aim of this research was introduction of important indices based on nearest neighbor analysis and their application in the investigation of ecological relationship between Persian oak coppice trees in Zagros forests. A 9 ha plot of these forests in Kohgilouye - BoyerAhmad province was selected that was completely homogeneous. This plot was covered with Persian oak coppice trees that their point map was obtained after registering their spatial location. Five nearest neighbor indices of G(r, F(r, J(r, GF(r and CE were then applied to study the spatial pattern and relationship of these trees. The results showed that Persian oak coppice trees were located regularly in the homogeneous plot and they were not dependent ecologically. These trees were independent and did not affect the establishment of each other.

  1. Analysis of landscape patterns and their relationship with oak (Quercus Humboldtii Bonpl.) regeneration in the municipality of Popayan, Cauca

    International Nuclear Information System (INIS)

    Cabezas Gaviria Alexander; Ospina Montealegre Roman

    2010-01-01

    Landscape patterns were determined for three different areas having oak populations in the Popayan municipality (Clarete, Rejoya and Pisoje). Two Landsat images from different years and polygons with areas equal or greater than 1.5 hectares were used for land use classification. Patch Analysis software was used in order to determine quantitative variables. Structure description included: number of patches, mean patch size, mean patch index, mean patch fractal dimension and mean perimeter-area ratio. Dispersion and fragmentation were evaluated with the three indexes: Mean Nearest Neighbor Distance, Mean Proximity Index and Interspersion Juxtaposition Index. Community variables included: basal area, terrain slope, light percentage and regeneration density, and were measured in an area of 3600 m2 for each landscape. Landscape and community information were analyzed using principal component analysis (PCA). The first two components explained 91.4% of data variability; they were determined mostly by landscape variables than community factors. Correlation analysis and the Kruskal-Wallis test showed that the variable of major importance regarding oak tree regeneration were the Neighbor Distance in secondary forest patches, the Mean Proximity Index in oak tree forest patches and the Juxtaposition Index in patches of planted forests.

  2. Constituents from oak bark (Quercus robur L.) inhibit degranulation and allergic mediator release from basophils and mast cells in vitro.

    Science.gov (United States)

    Lorenz, Peter; Heinrich, Miriam; Garcia-Käufer, Manuel; Grunewald, Franziska; Messerschmidt, Silke; Herrick, Anja; Gruber, Kim; Beckmann, Christiane; Knoedler, Matthias; Huber, Roman; Steinborn, Carmen; Stintzing, Florian C; Gründemann, Carsten

    2016-12-24

    Oak bark has been used since ancient times in Europaen ethnomedicine because of its adstringent, antimicrobial and hemostatic features, e.g. as a remedy for the treatment of wounds and skin diseases. Oak bark tannins are considered as bioactive natural products, interacting with surface proteins of mucous membranes and might be beneficial for the treatment of allergic diseases. This study investigated the effect of an oak bark decoction (OBD) and isolated tannin fractions on the degranulation capacity and cytokine/chemokine release from rat basophilic cells and human mast cells in vitro, which are essential for the initiation of early- and late-phase allergic reactions. By chromatographic separation on Sephadex ® LH-20 high- and low-molecular weight tannins were separated from OBD and the tannin composition analyzed by HPLC(DAD)-MS n . Then, the OBD and its fractions were tested in degranulation (β-hexosaminidase activity) of allergen-specific-activated basophilic cells in a photometric assay. The OBD and the high-molecular tannin fraction showed a dose-dependent inhibition of cell degranulation. Furthermore, the OBD and particularly its high molecular weight tannin fraction exhibited an inhibitory activity on the IL-8-, IL-6- and TNF-α-secretion from stimulated human mast cells, detected and quantified by ELISA. The OBD and its high-molecular weight tannins revealed an impact on allergic mediator release of basophilic cells and human mast cells and thereby provide a rationale for the topical treatment with OBD preparations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Recent growth coherence in long-term oak (Quercus spp.) ring width chronologies in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Dobrovolný, Petr; Rybníček, Michal; Büntgen, Ulf; Trnka, Miroslav; Brázdil, Rudolf; Stachoň, Z.; Prokop, O.; Kolář, Tomáš

    2016-01-01

    Roč. 70, 2-3 (2016), s. 133-141 ISSN 0936-577X R&D Projects: GA MŠk(CZ) LO1415; GA ČR GA13-04291S; GA MŠk(CZ) EE2.3.20.0248 Institutional support: RVO:67179843 Keywords : Tree-ring width chronology * Oak species * Tree-age structure * Site-specific conditions * Hydroclimate sensitivity * Czech Republic Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.578, year: 2016

  4. Capturing forest dependency in the central Himalayan region: Variations between Oak (Quercus spp.) and Pine (Pinus spp.) dominated forest landscapes.

    Science.gov (United States)

    Chakraborty, Anusheema; Joshi, Pawan Kumar; Sachdeva, Kamna

    2017-10-05

    Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pine-dominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistence-oriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized site-specific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.

  5. Mercury Distribution and Seasonal and Inter annual Variation of Mercury in Oak (Quercus ilex L.) in Almadenejos (Ciudad Real, Spain)

    International Nuclear Information System (INIS)

    Rodriguez-Alonso, J.; Sierra, M. J.; Millan, R.

    2014-01-01

    Plants that are exposed to environmental pollutants are able to accumulate them in their organs depending on plant species, type of organ or age among others. Evergreen plants can hold stems and leaves of the different age over the same branch. Thus, the amount of contaminants of these former organs could vary with its age because the contamination exposure time is different. The aim of this study is to know in a tree species, the mercury (Hg) distribution in it and the variation of Hg concentration in leaves and stems between consecutive years and along the same year. In order to carry this objective out, three different trees of Quercus ilex L. were selected and two branches were taken from each of them. Such trees are located in Almadenejos, a village from the Almaden mining district (Ciudad Real, Spain), an area well known due to the developed Hg mining activities for centuries. Considering each branch and each year, on average the results show that leaves had higher Hg concentration than stems. Furthermore, the lowest Hg concentration was measured in fruit (acorn). With regard to ageing effect on Hg concentration and taking into account each branch separately, the results show that the older leaves had higher Hg concentration than younger ones. Nevertheless, the oldest stems had not always higher Hg concentration than youngest ones. A seasonal variation in Hg content appeared both in leaves and in stems in 2010, increasing in 6.2 times on average, in about six months. This result suggests that this kind of organs should be analyzed in winter months. Finally, the results show a very high positive correlation between the Hg of the bark and the Hg of the wood in the sampled branches. Such result suggests that if bark is sampled and its Hg content is analyzed, we could know the Hg content in the big branches or in the trunk, avoiding the cutting of the branches or the whole tree. (Author)

  6. A new attempt at discrimination between Quercus petraea and Quercus robur based on wood anatomy

    OpenAIRE

    Feuillat, François; Dupouey, Jean-Luc; Sciama, Delphine; Keller, René

    1997-01-01

    The interspecific variability of wood anatomy between the two major oak species Quercus robur L. and Quercus petraea (Matt.) Liebl. is still largely unknown. However, anatomy strongly influences the technological properties of wood and the ecophysiological functioning of trees. Moreover, identification of oak wood species is a long-standing challenge and important for many purposes. In the Cîteaux Forest (Burgundy), 58 oaks from 14 mixed stands were sampled for wood anatomy characterization. ...

  7. Using a down-scaled bioclimate envelope model to determine long-term temporal connectivity of Garry oak (Quercus garryana) habitat in western North America: implications for protected area planning.

    Science.gov (United States)

    Pellatt, Marlow G; Goring, Simon J; Bodtker, Karin M; Cannon, Alex J

    2012-04-01

    Under the Canadian Species at Risk Act (SARA), Garry oak (Quercus garryana) ecosystems are listed as "at-risk" and act as an umbrella for over one hundred species that are endangered to some degree. Understanding Garry oak responses to future climate scenarios at scales relevant to protected area managers is essential to effectively manage existing protected area networks and to guide the selection of temporally connected migration corridors, additional protected areas, and to maintain Garry oak populations over the next century. We present Garry oak distribution scenarios using two random forest models calibrated with down-scaled bioclimatic data for British Columbia, Washington, and Oregon based on 1961-1990 climate normals. The suitability models are calibrated using either both precipitation and temperature variables or using only temperature variables. We compare suitability predictions from four General Circulation Models (GCMs) and present CGCM2 model results under two emissions scenarios. For each GCM and emissions scenario we apply the two Garry oak suitability models and use the suitability models to determine the extent and temporal connectivity of climatically suitable Garry oak habitat within protected areas from 2010 to 2099. The suitability models indicate that while 164 km(2) of the total protected area network in the region (47,990 km(2)) contains recorded Garry oak presence, 1635 and 1680 km(2) of climatically suitable Garry oak habitat is currently under some form of protection. Of this suitable protected area, only between 6.6 and 7.3% will be "temporally connected" between 2010 and 2099 based on the CGCM2 model. These results highlight the need for public and private protected area organizations to work cooperatively in the development of corridors to maintain temporal connectivity in climatically suitable areas for the future of Garry oak ecosystems.

  8. Leaf area index, leaf mass density, and allometric relationships derived from harvest of blue oaks in a California oak savanna

    Science.gov (United States)

    John F. Karlik; Alistair H. McKay

    2002-01-01

    Given the key role played by biogenic volatile organic compounds (BVOC) in tropospheric chemistry and regional air quality, it is critical to generate accurate BVOC emission inventories. Because oak species found in California often have high BVOC emission rates, and are often of large stature with corresponding large leaf masses, oaks may be the most important genus...

  9. Adsorption of Zn(II) in aqueous solution by activated carbons prepared from evergreen oak (Quercus rotundifolia L.).

    Science.gov (United States)

    Gómez-Tamayo, M del Mar; Macías-García, Antonio; Díaz Díez, M Angeles; Cuerda-Correa, Eduardo M

    2008-05-01

    In the present work activated carbons have been prepared from evergreen oak wood. Different samples have been prepared varying the concentration of the activating agent (H(3)PO(4)) and the treatment temperature. The yield of the process decreases with increasing phosphoric acid concentrations. Furthermore, high concentrations of activating agent lead to mainly mesoporous activated carbons to the detriment of the microporous texture. Treatment temperatures up to 450 degrees C lead to a progressive increase of the micro- and mesopore volumes. Values of specific surface area (S(BET)) as high as 1723 m(2) g(-1)have been obtained using appropriate phosphoric acid concentrations and treatment temperatures. The samples prepared have been successfully used in the removal of Zn(II) from aqueous solutions. From the adsorption kinetic data it may be stated that the equilibrium time is, in all cases, below 170 h. The adsorption process as a rule becomes faster as the mesopore volume and specific surface area of the samples increase. The adsorption isotherms in liquid phase point out that the adsorption capacity (n(0)(s)) and the affinity towards the solute (K(ci)) are higher for the sample showing the most developed mesoporous texture and surface area as well.

  10. Silvicultural options in ageing holm oak (Quercus ilex L. coppices in Gargano: results after 14 growing seasons

    Directory of Open Access Journals (Sweden)

    Scopigno D

    2008-12-01

    Full Text Available In the frame of a long-term research program concerning management of ageing holm oak coppices, results available after 14 growing seasons are reported in present paper. Experimental treatments include: A 50 standards per hectare, all of the same age; B 250 standards per hectare, all of the same age; C 140 standards per hectare, with two different ages; D conversion to high forest; E natural evolution (control. A total of 15 permanent plots were established (5 treatments x 3 replicates per treatment and the experimental design used is that of randomised blocks. Based on observations concerning seedlings and shoots development and standards growth and competitive effects, the following preliminary results may be highlighted: i recovering the traditional coppicing system with few standards per hectare represents a valid option from both ecological and shoots growth point of view; the stools, with few standards per hectare, showed a larger number of sprouts, provided with a higher average height and larger diameters; ii uneven-aged standards represent a good alternative form the points of view of both landscape impact immediately after felling operations and stand resistance to climatic damages; iii a good alternative is to apply conversion treatments to high forest, whenever their site quality allows these operations.

  11. Field monoterpene emission of Mediterranean oak (Quercus ilex) in the central Iberian Peninsula measured by enclosure and micrometeorological techniques: Observation of drought stress effect

    Science.gov (United States)

    Plaza, J.; NúñEz, L.; Pujadas, M.; PéRez-Pastor, R.; Bermejo, V.; GarcíA-Alonso, S.; Elvira, S.

    2005-02-01

    An experimental characterization of biogenic emission from Quercus ilex ssp. rotundifolia in a forest near Madrid, Spain, was carried out in the early autumn of the years 2000-2003. A dynamic branch enclosure technique was implemented to determine the monoterpene emission rates of this evergreen oak species during the 2000 and 2001 campaigns. Major compounds emitted during both measurement periods were limonene, α-pinene, β-pinene, sabinene, and myrcene. In the 2000 field campaign the light- and temperature-dependent model of [1993] did not fit the data due to drastic reductions of emission rates (and leaf gas exchange related parameters) observed at high air temperature and low air humidity (high water vapor pressure deficit). This plant physiological activity depletion and the subsequent emission reduction were attributed to severe water soil deficit conditions, as precipitation was very scarce during the growing season. In contrast, during the 2001 field campaign, neither emission nor physiological activity showed strong decreases in hot days. A good fit of experimental data to Guenther model was achieved in this field campaign (r2 = 0.90), and linear regression gave a standard emission factor (ES) of 14.0 μg gdw-1 h-1 (gdw is grams dry weight). Soil moisture was presumably higher than during the 2000 campaign due to recent rain events. With the purpose of documenting the drought stress effect at canopy level, monoterpene oak fluxes were measured by the modified Bowen ratio micrometeorological technique throughout the 2001 field campaign and in the late summer of 2002 and 2003. The measured emission by both techniques showed a reasonably good correlation, although micrometeorological fluxes were, in general, lower than upscaled branch emission rates. According to Guenther's parameterization, standard emission fluxes (FS) of 0.30 μg m-2 s-1 (r2 = 0.61) and 0.28 μg m-2 s-1 (r2 = 0.67) were derived for the 2001 and 2002 field campaigns, respectively. However

  12. Analytical approaches to the determination of simple biophenols in forest trees such as Acer (maple), Betula (birch), Coniferus, Eucalyptus, Juniperus (cedar), Picea (spruce) and Quercus (oak).

    Science.gov (United States)

    Bedgood, Danny R; Bishop, Andrea G; Prenzler, Paul D; Robards, Kevin

    2005-06-01

    Analytical methods are reviewed for the determination of simple biophenols in forest trees such as Acer (maple), Betula (birch), Coniferus, Eucalyptus, Juniperus (cedar), Picea (spruce) and Quercus (oak). Data are limited but nevertheless clearly establish the critical importance of sample preparation and pre-treatment in the analysis. For example, drying methods invariably reduce the recovery of biophenols and this is illustrated by data for birch leaves where flavonoid glycosides were determined as 12.3 +/- 0.44 mg g(-1) in fresh leaves but 9.7 +/- 0.35 mg g(-1) in air-dried samples (data expressed as dry weight). Diverse sample handling procedures have been employed for recovery of biophenols. The range of biophenols and diversity of sample types precludes general procedural recommendations. Caution is necessary in selecting appropriate procedures as the high reactivity of these compounds complicates their analysis. Moreover, our experience suggests that their reactivity is very dependent on the matrix. The actual measurement is less contentious and high performance separation methods particularly liquid chromatography dominate analyses whilst coupled techniques involving electrospray ionization are becoming routine particularly for qualitative applications. Quantitative data are still the exception and are summarized for representative species that dominate the forest canopy of various habitats. Reported concentrations for simple phenols range from trace level (<0.1 microg g(-1)) to in excess of 500 microg g(-1) depending on a range of factors. Plant tissue is one of these variables but various biotic and abiotic processes such as stress are also important considerations.

  13. Effects of sodium chloride salinity on ecophysiological and biochemical parameters of oak seedlings (Quercus robur L.) from use of de-icing salts for winter road maintenance.

    Science.gov (United States)

    Laffray, Xavier; Alaoui-Sehmer, Laurence; Bourioug, Mohamed; Bourgeade, Pascale; Alaoui-Sossé, Badr; Aleya, Lotfi

    2018-04-04

    Salt is widely used to melt snow on roads especially in mountain regions. Whether as rock salt or aerosols, spread or sprayed over road surfaces, salt may result in increased salt concentrations in soils, which, in turn, affect natural vegetation, especially tree seedlings already subjected to various other types of abiotic stress. The authors investigated the effects of salt treatment-related stress on seedling growth and certain biochemical parameters in Quercus robur to determine ion concentrations in root tips. Seedlings growing in a quartz sand/vermiculite mixture were subjected to NaCl concentrations of 0, 50, or 100 mM for 5 weeks. The results showed that high NaCl concentrations caused a marked reduction in total leaf biomass 55 and 75% for 50 and 100 mM treatments, respectively, in dry weight of stems (84%) and roots (175%) for 100 mM treatment and modified root architecture, whereas no changes appeared in leaf number. A non-significant decrease in relative water content, with changes in ion balance was recorded. Comparison of stressed to control plants show an increase in sodium (3.5-8-fold), potassium (0.6-fold), and chloride (9.5-14-fold) concentrations in the root tips while the K + /Na + ratio decreased. In taproots, no significant biochemical differences were observed between the salt-treated and the control plants for acid invertase activity, reducing sugars, sucrose, or soluble protein contents. The significance of ion and sugar accumulations in relation to osmotic adjustment and the ability of oak seedlings to cope with salt stress are discussed.

  14. Effect of human disturbance on seed and seedling distribution of the Andean Oak (Quercus humboldtii Bonpl., Fagaceae) in the Colombian Eastern Cordillera

    International Nuclear Information System (INIS)

    Guerrero Rodriguez, Sandra Bibiana; Paz Camacho, Erika Andrea; Parrado Rosselli, Angela

    2010-01-01

    Animals affect the spatial occupation patterns of tropical forest plants throughout the seed dispersal they perform. Therefore, changes in vertebrate populations by human disturbance might affect re generation dynamics of plant species. We studied differences in the spatial distribution of seeds and seedlings of the Andean oak (Quercus humboldtii) between two nearby forests with contrasting levels of anthropogenic influence in the Colombian Andes. Density and spatial distribution of seedlings were evaluated in 490 and 484 1 m2 plots located in a 28 ha area, in the high and low disturbed site, respectively. In each plot, all seedlings found were sampled and classified into three age categories. Density and spatial distribution of seeds were evaluated in 0.25 m 2s ubplots placed in the same plots described above. Results showed a higher number and density of seedlings in the high disturbed site, as well as a marked decrease in seedling density as age increases. Distances to the nearest neighbour were shorter in the high disturbed site for all seedlings and each age category, in contrast to the low disturbed site. Indexes of spatial distribution indicate an aggregated pattern in the most disturbed site, while a uniform pattern in the low disturbed one. Seeds also exhibited an aggregated pattern in the high disturbed site and a higher seed predation by invertebrates. Results seemed to be a consequence of forest fragmentation and a decrease of vertebrate seed dispersers, seed predators and herbivores associated to the regeneration processes of the species. These results provide important information for the forest management and restoration activities, since in order to maintain plant populations in the long term, presence and viable populations of seed dispersers should be also maintained.

  15. Do chestnut, northern red, and white oak germinant seedlings respond similarly to light treatments? Growth and biomass

    Science.gov (United States)

    Joanne Rebbeck; Kurt Gottschalk; Amy. Scherzer

    2011-01-01

    Northern red oak (Quercus rubra L.) seedling growth has been extensively studied. White oak (Quercus alba L.) and chestnut oak (Quercus prinus L.), however, are far less investigated despite their importance among upland oak species in eastern North American forests. We characterized white and chestnut oak...

  16. Effects of fire temperature on the physical and chemical characteristics of the ash from two plots of Cork oak (Quercus Suber)

    Science.gov (United States)

    Ubeda, X.; Pereira, P.; Outeiro, L.; Martin, D.A.

    2009-01-01

    Cork oak, (Quercus suber) is widely distributed in the Mediterranean region, an area subject to frequent fires. The ash produced by burning can have impacts on the soil status and water resources that can differ according to the temperature reached during fire and the characteristics of the litter, defined as the dead organic matter accumulated on the soil surface prior to the fire. The aim of this work is to determine the physical and chemical characteristics of ash produced in laboratory experiments to approximate conditions typical of fires in this region. The litter of Quercus suber collected from two different plots on the Iberian Peninsula, Mas Bassets (Catalonia) and Albufeira (Portugal), was combusted at different temperatures for 2h. We measured Mass Loss (ML per cent), ash colour and CaCO3 content, pH, Electrical Conductivity (EC) and the major cations (Ca2+, Mg2+, K+ and Na+) released from ash slurries created by mixing ash with deionized water. The results showed that ML per cent is higher at all temperatures in Albufeira samples compared to Mas Bassets samples, except at 550??C, and the rate of loss increases faster with temperature than the Mas Bassets samples. At 150??C the ash colour is yellowish, becoming reddish at 200- 250??C and black at 300??C. Above 400??C the ash is grey/white. This thermal degradation is mostly observed in Albufeira litter. The formation of CaCO3 was identified at a lower temperature in Albufeira litter. At temperatures ash slurries. The analysis of the Ca:Mg ratio also showed that for the same temperature, a higher severity results for Albufeira litter. Potential negative effects on soil properties are observed at medium and higher temperatures. These negative effects include a higher percentage of mass loss, meaning more soil may be exposed to erosion, higher pH values and greater cation release from ash, especially monovalalent cations (K+,Na+) in higher proportions than the divalent ions (Ca2+, Mg2+), that can lead to

  17. Repeated Summer Drought and Re-watering during the First Growing Year of Oak (Quercus petraea) Delay Autumn Senescence and Bud Burst in the Following Spring

    Science.gov (United States)

    Vander Mijnsbrugge, Kristine; Turcsán, Arion; Maes, Jorne; Duchêne, Nils; Meeus, Steven; Steppe, Kathy; Steenackers, Marijke

    2016-01-01

    Climate change predicts harsher summer droughts for mid-latitudes in Europe. To enhance our understanding of the putative impacts on forest regeneration, we studied the response of oak seedlings (Quercus petraea) to water deficit. Potted seedlings originating from three locally sourced provenances were subjected to two successive drought periods during the first growing season each followed by a plentiful re-watering. Here, we describe survival and phenological responses after the second drought treatment, applying general linear mixed modeling. From the 441 drought treated seedlings 189 subsisted with higher chances of survival among smaller plants and among single plants per pot compared to doubles. Remarkably, survival was independent of the provenance, although relatively more plants had died off in two provenances compared to the third one with mean plant height being higher in one provenance and standard deviation of plant height being higher in the other. Timing of leaf senescence was clearly delayed after the severe drought treatment followed by re-watering, with two seedlings per pot showing a lesser retardation compared to single plants. This delay can be interpreted as a compensation time in which plants recover before entering the subsequent developmental process of leaf senescence, although it renders seedlings more vulnerable to early autumn frosts because of the delayed hardening of the shoots. Onset of bud flush in the subsequent spring still showed a significant but small delay in the drought treated group, independent of the number of seedlings per pot, and can be considered as an after effect of the delayed senescence. In both phenological models significant differences among the three provenances were detected independent from the treatment. The only provenance that is believed to be local of origin, displayed the earliest leaf senescence and the latest flushing, suggesting an adaptation to the local maritime climate. This provenance also

  18. Repeated summer drought and re-watering during the first growing year of oak (Quercus petraea delay autumn senescence and bud burst in the following spring

    Directory of Open Access Journals (Sweden)

    Kristine Vander Mijnsbrugge

    2016-03-01

    Full Text Available Climate change predicts harsher summer droughts for mid-latitudes in Europe. To enhance our understanding of the putative impacts on forest regeneration, we studied the response of oak seedlings (Quercus petraea to water deficit. Potted seedlings originating from three locally sourced provenances were subjected to two successive drought periods during the first growing season each followed by a plentiful re-watering. Here we describe survival and phenological responses after the second drought treatment, applying general linear mixed modelling. From the 441 drought treated seedlings 189 subsisted with higher chances of survival among smaller plants and among single plants per pot compared to doubles. Remarkably, survival was independent of the provenance, although relatively more plants had died off in two provenances compared to the third one with mean plant height being higher in one provenance and standard deviation of plant height being higher in the other. Timing of leaf senescence was clearly delayed after the severe drought treatment followed by re-watering, with two seedlings per pot showing a lesser retardation compared to single plants. This delay can be interpreted as a compensation time in which plants recover before entering the subsequent developmental process of leaf senescence, although it renders seedlings more vulnerable to early autumn frosts because of the delayed hardening of the shoots. Onset of bud flush in the subsequent spring still showed a significant but small delay in the drought treated group, independent of the number of seedlings per pot, and can be considered as an after effect of the delayed senescence. In both phenological models significant differences among the three provenances were detected independent from the treatment. The only provenance that is believed to be local of origin, displayed the earliest leaf senescence and the latest flushing, suggesting an adaptation to the local maritime climate. This

  19. Oak Tree Planting Project

    Science.gov (United States)

    Sherryl L. Nives; William D. Tietje; William H. Weitkamp

    1991-01-01

    An Oak Tree Planting Project was conducted during 1989/90 in San Luis Obispo County by the Integrated Hardwood Range Management Program (IHRMP)/Central Coast. The local media and an IHRMP workshop were used to publicize the Planting Project and give information on the status of oaks (Quercus spp.) in California and oak planting techniques. Outreach...

  20. CARACTERÍSTICAS FLORÍSTICAS DE UN BOSQUE DE ROBLE (Quercus humboldtii EN LA MESETA DE POPAYÁN (CAUCA CARACTERÍSTICAS DE FLORÍSTICAS ONU BOSQUE DE ROBLE (Quercus humboldtii EN LA MESETA DE POPAYÁN (CAUCA FLORISTIC CHARACTERISTICS OF A OAK FOREST (Quercus humboldtii ON THE PLATEAU OF POPAYÁN (CAUCA

    Directory of Open Access Journals (Sweden)

    ROMÁN OSPINA M

    2012-12-01

    Full Text Available Para estudiar las características florísticas de un bosque de roble (Quercus humboldtii, se estableció una parcela de 9600 m² dividida en 24 subparcelas de 20x20 metros, en las que se registró el nombre científico, diámetro a la altura del pecho (dap, altura total y altura de reiteración, condición de luz y calidad de fuste para los individuos con dap>10 cm; dentro de cada subparcela se inscribieron parcelas de 10x10 metros para registrar la información de individuos >1.5 metros de altura y con dap 40 cm de altura de especies arbóreas, palmas y herbáceas grandes. En los 0.96 ha se reportaron un total de 51 especies, agrupadas 44 géneros y en 33 familias botánicas para las tres categorías de tamaño; las especies más abundantes y mejor distribuidas en la categoría >0.4 m 10 centímetros de diámetro a la altura del pecho fue de 455 ha-1, que representan un área basal de 15.8 m²ha-1 indicando que es un bosque joven.Para estudar as características florísticas da floresta de carvalhos (Quercus humboldtii estabeleceu um lote de 9600 m² divididos em 24 subparcelas de 20x20 metros, onde não havia nome científico, o diâmetro à altura do peito, altura total e altura de repetição, condições de luz e 10 cm em cada de qualidade para os indivíduos com diâmetro à altura do peito subparcela foram incluídos lotes 10x10 metros para registrar informações sobre 1,5 metros de altura e diâmetro>indivíduos 10 cm e de5x5 metros parcelas para gravar regeneração estabelecido árvores, palmeiras e herbáceas de grande porte. Em 0,96 foi relatado um total de 51 espécies, agrupadas 44 gêneros e 33 famílias botânicas para as três categorias de tamanho, as mais abundantes e bem distribuídas na categoria > 0,4 m 10 cm de diâmetro à altura do peito foi de 455 ha-1, representando uma área basal de 15,8 m²ha-1, indicando que é uma floresta jovemTo study the floristic characteristics of a oak forest (Quercus humboldtii

  1. Padrão sazonal do regime estomático em azinheiras (Quercus rotundifolia Lam. regadas Seasonal pattern of the stomatal regime of irrigated holm-oak (Quercus rotundifolia Lam.

    Directory of Open Access Journals (Sweden)

    F. Melhorado

    2007-01-01

    êntico tanto no Verão como no Inverno. Conclui-se que a diferença entre o Verão e o Inverno no padrão comportamental da espécie, ou seja, a passagem de aumento exponencial das resistências para bimodal no Inverno, onde se evidencia o “midday-closure”, se deve, provavelmente, à menor solicitação evaporativa durante o ocaso no período de Inverno. Confirmou-se a existência do “middayclosure” na espécie como uma adaptação não rígida, dependente da disponibilidade hídrica do solo.This project aims to study the possible variation in stomata regime between irrigated oak trees Quercus rotundifolia Lam. and the same trees under natural environmental conditions at the different seasons of the year. The study was carried in a montado situated in Mitra, southeast of Portugal, at 13 km from Évora. For this project two isolated trees were selected, one irrigated to keep the plant regularly water supplied and the other subjected to the typical dryness of our summer (we will call this the standard tree. The stomatal resistance was measured with a porometer (?AP4 at three daily periods (morning, noon and sunset in the hydrologic year of 2001-02. During the summer the stomata resistances of the irrigated tree were significantly different from the standard (99%; alfa = 0,01, presenting always the double of the stomatic aperture of the standard tree. This relation lasted through all daily periods of the season. In the summer the average of stomata resistances in both trees follows an exponential curve (r² = 0,99, with a maximum of resistance at the sunset. In winter, the differences in stomata resistance between the two trees are significative (at 99%; alfa = 0,01 over all daily period. And we have observed a change in the daily variation pattern of the resistances, becoming more visible a midday-closure, especially in the standard tree. The resistance curves follow a bimodal pattern (r² = 1 in both trees with the maximum at noon. In the irrigated tree, however, the

  2. Distance and phenology influence pollen gene flow, male reproductive success, and female mate choice in a northern red oak (Quercus rubra L.) seed orchard

    Science.gov (United States)

    Northern red oak is a high-value hardwood used for lumber, furniture and veneer. Intensively managed northern red oak orchards require genetic gain for trait improvement. Data from conifer seed orchards and natural and managed stands of hardwood trees have shed light on the distance over which polle...

  3. A review of oak wilt management: a summary of treatment options and their efficacy

    Science.gov (United States)

    Karrie A. Koch; Gina L. Quiram; Robert C. Venette

    2010-01-01

    Oak wilt, caused by the invasive fungal pathogen Ceratocystis fagacearum (Bretz) Hunt, is a serious and fatal disease of oaks, Quercus spp., with red oaks (section Lobatae) generally being more susceptible than white oaks (section Quercus). Oak wilt was first recognized in North America in 1944...

  4. Phylogenetic relationships of the genus Quercus L. (Fageceae) from ...

    African Journals Online (AJOL)

    ProBook

    2016-10-05

    , Q. robur L., Q. infectoria Oliver, Q. cerris L., .... infectoria oliver known as white oaks, Quercus cerris L.,. Q. ithaburensis subsp. ... and for each tree ten young and fresh leaves were collected for molecular study. After that leaf ...

  5. Oak forests types of quercus humboldtii in the Guantiva-La Rusia-Iguaque corridor (Santander-Boyacá, Colombia): their conservation and sustainable use

    OpenAIRE

    Andrés Avella Muñoz; J. Orlando Rangel Churio

    2014-01-01

    Los bosques de robles en el corredor Guantiva-La Rusia-Iguaque corresponden a la formación mayor de Quercus humboldtii y Billia rosea, los cuales se clasificaron en una estructura jerárquica de siete tipos: Bosques de Q. humboldtii y Ocotea calophylla(franja altoandina > 3200 m), la gran formación de Q. humboldtii y Alchornea grandiflora, en la región andina con el robledal de Q. humboldtii - Blakea cuatrecasii y el de Q. humboldtii - Cyathea multiflora. En la parte baja de la región andina s...

  6. Identification of fungal plant pathogens associated with oak (Quercus humboldtii Bonpl.), In the municipalities of Encino (Santander), Arcabuco, and Tipacoque (Boyaca)

    International Nuclear Information System (INIS)

    Monroy Castro, Leidi Yunari; Lizarazo Forero, Luz Marina

    2010-01-01

    The objectives of this study were to isolate and determine the presence of the pathogen Phytophthora ramorum and other potential pathogens of Quercus humboldtii, and evaluate the possibility of using the antagonistic capacity of bacteria isolated from rhizosphere and phyllosphere against them. The study was conducted in the conservation corridor Guantiva - La Rusia - Iguaque, in the municipalities of Encino (Santander), Arcabuco and Tipacoque (Boyaca). The phytopathogenic fungi were isolated using direct seeding of leaves with symptoms of fungal infection in OGY, Sabouraud, and PDA + Lactic acid at 0.2%. We used the plate counting technique for the isolation of bacteria from rhizospheric and bulk soil. Phytophthora ramorum was not isolated, but phytopathogenic fungi of the genus Fusarium spp., and Pestalotia spp., were obtained in the isolates. Microbial populations of rhizospheric and bulk soil were scarce, exhibited low diversity, and were dominated by few morphotypes. We identified four species of bacteria: Pseudomonas fluorescens, Bacillus macerans, Pinus sylvestris and Staphylococcus epidermidis. The phyllosphere community was dominated by Pseudomonas fluorescens. The species Pseudomonas fluorescens and Pinus sylvestris did not exhibited antagonistic properties against Pestalotia spp. Further studies are required to confirm Fusarium spp., and Pestalotia spp., pathogenic activity against Quercus humboldtii.

  7. [Effects of fire recurrence on fire behaviour in cork oak woodlands (Quercus suber L.) and Mediterranean shrublands over the last fifty years].

    Science.gov (United States)

    Schaffhauser, Alice; Pimont, François; Curt, Thomas; Cassagne, Nathalie; Dupuy, Jean-Luc; Tatoni, Thierry

    2015-12-01

    Past fire recurrence impacts the vegetation structure, and it is consequently hypothesized to alter its future fire behaviour. We examined the fire behaviour in shrubland-forest mosaics of southeastern France, which were organized along a range of fire frequency (0 to 3-4 fires along the past 50 years) and had different time intervals between fires. The mosaic was dominated by Quercus suber L. and Erica-Cistus shrubland communities. We described the vegetation structure through measurements of tree height, base of tree crown or shrub layer, mean diameter, cover, plant water content and bulk density. We used the physical model Firetec to simulate the fire behaviour. Fire intensity, fire spread, plant water content and biomass loss varied significantly according to fire recurrence and vegetation structure, mainly linked to the time since the last fire, then the number of fires. These results confirm that past fire recurrence affects future fire behaviour, with multi-layered vegetation (particularly high shrublands) producing more intense fires, contrary to submature Quercus woodlands that have not burnt since 1959 and that are unlikely to reburn. Further simulations, with more vegetation scenes according to shrub and canopy covers, will complete this study in order to discuss the fire propagation risk in heterogeneous vegetation, particularly in the Mediterranean area, with a view to a local management of these ecosystems. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  8. Do chestnut, northern red, and white oak germinant seedlings respond similary to light treatments? II. Gas exchange and chlorophyll responses

    Science.gov (United States)

    Joanne Rebbeck; Amy Scherzer; Kurt. Gottschalk

    2012-01-01

    Understanding differences in physiological and growth strategies in low-light environments among upland oak species may help managers address the challenges of oaks' poor regeneration. Gas exchange and chlorophyll content were measured for northern red oak (Quercus rubra L.), chestnut oak (Quercus prinus L.), and white oak (...

  9. Sudden oak death in California: what is the potential?

    Science.gov (United States)

    Tara M. Barrett; Demetrios Gatziolis; Jeremy S. Fried; Karen L. Waddell

    2006-01-01

    Sudden oak death, a disease associated with the pathogen Phytophthora ramorum, has a large number of shrub and tree host species. Three of the tree species must susceptible to mortality from the disease, California black oak (Quercus kelloggii), coast live oak (Quercus agrifolia), and tanoak (...

  10. Pollen gene flow, male reproductive success, and genetic correlations among offspring in a northern red oak (Quercus rubra L. seed orchard.

    Directory of Open Access Journals (Sweden)

    Lisa Alexander

    Full Text Available Northern red oak is a high-value hardwood used for lumber, furniture and veneer. Intensively managed northern red oak seed orchards are required to obtain genetic gain for trait improvement. Data from conifer seed orchards and natural and managed stands of hardwood trees have shed light on the distance over which pollen can move, and underscore the need for managerial attention to seed orchard design, placement, and maintenance. We used eleven microsatellite markers to investigate pollen gene flow, female mate choice, and male reproductive success in a clonal seed orchard of northern red oak based on paternity analysis of seed orchard offspring in progeny tests. Nearly all (93% offspring were sired by a male parent within the seed orchard. The mean number of male parents per year was 69.5, or 47.6% of all clones in the seed orchard. Female clones in the early phenology group had more offspring sired from extra-orchard pollen (13% than clones in the intermediate (5% and late (1% phenology groups. Distance was the largest influence on pollination success, and pollination occurred most often by male trees in the same subline as the maternal tree. Males in the early phenology group sired more offspring overall in the progeny pool and more offspring per mother tree than males in the intermediate or late phenology groups. Average genetic correlations among all OP progeny ranged between 0.2557 and 0.3529 with a mean of 0.28±0.01. The importance of progeny test genotyping for northern red oak improvement likely is increasing with the demand for improved varieties. The current study demonstrated the feasibility of post hoc assembly of full-sib families for genetic analysis.

  11. Pollen gene flow, male reproductive success, and genetic correlations among offspring in a northern red oak (Quercus rubra L.) seed orchard.

    Science.gov (United States)

    Alexander, Lisa; Woeste, Keith

    2017-01-01

    Northern red oak is a high-value hardwood used for lumber, furniture and veneer. Intensively managed northern red oak seed orchards are required to obtain genetic gain for trait improvement. Data from conifer seed orchards and natural and managed stands of hardwood trees have shed light on the distance over which pollen can move, and underscore the need for managerial attention to seed orchard design, placement, and maintenance. We used eleven microsatellite markers to investigate pollen gene flow, female mate choice, and male reproductive success in a clonal seed orchard of northern red oak based on paternity analysis of seed orchard offspring in progeny tests. Nearly all (93%) offspring were sired by a male parent within the seed orchard. The mean number of male parents per year was 69.5, or 47.6% of all clones in the seed orchard. Female clones in the early phenology group had more offspring sired from extra-orchard pollen (13%) than clones in the intermediate (5%) and late (1%) phenology groups. Distance was the largest influence on pollination success, and pollination occurred most often by male trees in the same subline as the maternal tree. Males in the early phenology group sired more offspring overall in the progeny pool and more offspring per mother tree than males in the intermediate or late phenology groups. Average genetic correlations among all OP progeny ranged between 0.2557 and 0.3529 with a mean of 0.28±0.01. The importance of progeny test genotyping for northern red oak improvement likely is increasing with the demand for improved varieties. The current study demonstrated the feasibility of post hoc assembly of full-sib families for genetic analysis.

  12. Identification of Quercus agrifolia (coast live oak resistant to the invasive pathogen Phytophthora ramorum in native stands using Fourier-transform infrared (FT-IR spectroscopy

    Directory of Open Access Journals (Sweden)

    Anna Olivia Conrad

    2014-10-01

    Full Text Available Over the last two decades coast live oak (CLO dominance in many California coastal ecosystems has been threatened by the alien invasive pathogen Phytophthora ramorum, the causal agent of sudden oak death. In spite of high infection and mortality rates in some areas, the presence of apparently resistant trees has been observed, including trees that become infected but recover over time. However, identifying resistant trees based on recovery alone can take many years. The objective of this study was to determine if Fourier-transform infrared (FT-IR spectroscopy, a chemical fingerprinting technique, can be used to identify CLO resistant to P. ramorum prior to infection. Soft independent modeling of class analogy identified spectral regions that differed between resistant and susceptible trees. Regions most useful for discrimination were associated with carbonyl group vibrations. Additionally, concentrations of two putative phenolic biomarkers of resistance were predicted using partial least squares regression; > 99% of the variation was explained by this analysis. This study demonstrates that chemical fingerprinting can be used to identify resistance in a natural population of forest trees prior to infection with a pathogen. FT-IR spectroscopy may be a useful approach for managing forests impacted by sudden oak death, as well as in other situations where emerging or existing forest pests and diseases are of concern.

  13. Assessing wood quality of borer-infested red oak logs with a resonance acoustic technique

    Science.gov (United States)

    Xiping Wang; Henry E. Stelzer; Jan Wiedenbeck; Patricia K. Lebow; Robert J. Ross

    2009-01-01

    Large numbers of black oak (Quercus velutina Lam.) and scarlet oak (Quercus coccinea Muenchh.) trees are declining and dying in the Missouri Ozark forest as a result of oak decline. Red oak borer-infested trees produce low-grade logs that become extremely difficult to merchandize as the level of insect attack increases. The objective of this study was to investigate...

  14. Fire effects on Gambel oak in southwestern ponderosa pine-oak forests

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain...

  15. Spatio-temporal analysis of oak forests (Quercus humboldtii Bonpl.) change and its relationship with pottery at Aguabuena (Raquira-Boyaca)

    International Nuclear Information System (INIS)

    Moncada Rasmussen, Dora Maria

    2010-01-01

    This research was conducted at Aguabuena, Raquira-Boyaca, and the main objective was to identify the changes in the settlement patterns and oak - forest cover, due to the development of new technologies and destinies for ceramics production. The study was carried out using aerial photographs from 1985 and 1993 processed in ArcGIS v. 9.0, as well as the application of participatory methods and spatial statistics. The spatio-temporal analysis of the forests allowed the measurement of perimeter and area changes and the number of fragments, where the loss of forest cover was 43.43% for the evaluated years. For analytical purposes related to the ceramics production organization, two different types of workshops can be pointed out: Domestic and Family - Industry. In the Domestic workshops spatial aggregation is due to the forest presence, its relative and different antiquity. The family - indus try- workshops are located along roads, for their relatives and population increment. Each ceramic production system represents different forms of relations with nature; the domestic ones are located in the oaks forests, using high quality fuel in the heating ceramics, while the Industrial-Family looks for the roads with the purpose of centralizing the production and favoring the intermediate relations. These two modes of production reflect the human role in the change and creation of new land scapes from the pottery.

  16. Risk analysis and guidelines for harvest activities in wisconsin oak timberlands to minimize oak wilt threat

    Science.gov (United States)

    Jennifer Juzwik; Jane Cummings-Carlson; Kyoko Scanlon

    2010-01-01

    Oaks (Quercus spp.) are an important species group in the forests of Wisconsin. The State’s timberland typed as oak-hickory forest was estimated at 2.9 million acres in 1996. Growing stock volume for red oak was estimated at 2.4 billion cubic feet, whereas select white oak volume was estimated to be 927 million cubic feet. Oak wilt, the oak disease...

  17. Oak forests types of quercus humboldtii in the Guantiva-La Rusia-Iguaque corridor (Santander-Boyacá, Colombia: their conservation and sustainable use

    Directory of Open Access Journals (Sweden)

    Andrés Avella Muñoz

    2014-06-01

    Full Text Available Los bosques de robles en el corredor Guantiva-La Rusia-Iguaque corresponden a la formación mayor de Quercus humboldtii y Billia rosea, los cuales se clasificaron en una estructura jerárquica de siete tipos: Bosques de Q. humboldtii y Ocotea calophylla(franja altoandina > 3200 m, la gran formación de Q. humboldtii y Alchornea grandiflora, en la región andina con el robledal de Q. humboldtii - Blakea cuatrecasii y el de Q. humboldtii - Cyathea multiflora. En la parte baja de la región andina se diferenciaron los bosques de Q. humboldtii y Daphnopsis caracasana y los de Q. humboldtii y Pouteria baehniana. Los bosques de Virola macrocarpa y Q. humboldtii están presentes en la zona de vida sub-andina. Los robledales son considerados ecosistemas de alto valor cultural y social con dos prácticas principales de uso: como fuente de combustible y en el mantenimiento de las fincas (postes, estacas, madera. Según la caracterización florística y estructural, los bosques de Virola macrocarpa - Q. humboldtii, los de Q. humboldtii - Pouteria baehniana y los de Q. humboldtii - Daphnopsis caracasana podrían ser utilizados por la comunidad, bajo prescripciones técnicas. Los bosques de Q. humboldtii - Blakea cuatrecasii y de Q. humboldtii - Ocoteo calophylla no se deben usar, bajo ninguna condición, y deben ser objeto de un programa de protección estricta y restauración ecológica. Se deben implementar estrategias de conservación basadas en la generación de acuerdos de co-manejo entre las comunidades locales y las instituciones ambientales que faciliten su conservación bajo esquemas de uso sostenible.

  18. The epidemiology of sudden oak death in Oregon forests

    Science.gov (United States)

    Ebba K. Peterson

    2011-01-01

    The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in't Veld), causal agent of Sudden Oak Death (SOD) of oaks (Quercus spp.) and tanoaks (Notholithocarpus densiflorus syn. Lithocarpus densiflorus...

  19. Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

    Science.gov (United States)

    Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

    2008-01-01

    How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...

  20. Purification of a new isoform of laccase from a Marasmius quercophilus strain isolated from a cork oak litter (Quercus suber L).

    Science.gov (United States)

    Farnet, A M; Criquet, S; Pocachard, E; Gil, G; Ferre, E

    2002-01-01

    A new isoform of laccase from Marasmius quercophilus is described in this study. The strain of this white-rot fungus was isolated for the first time on a cork oak litter. This isoform exhibited certain common properties of laccases (a molecular weight of 65 Kda, an optimum pH of 6.2 with syringaldazine). But this laccase has also particularly novel features: the best activity measured was observed at high temperatures (80 C) and this isoform was not inhibited with EDTA. Furthermore, this induced laccase was able to transform most of the aromatic compounds tested without the addition of mediators to the reaction mixture, and the transformation of certain chlorophenols (2-chlorophenol and 2,4-dichlorophenol) by a laccase isoform from M. quercophilus is reported here for the first time. We also demonstrate the importance of 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonate) (ABTS) as a mediator since it allowed veratryl alcohol and p-hydroxybenzoic acid transformation. Moreover, new products of transformation were observed using the combination of ABTS with this isoform of laccase.

  1. Influence of Scarification on the Germination Capacity of Acorns Harvested from Uneven-Aged Stands of Pedunculate Oak (Quercus robur L.

    Directory of Open Access Journals (Sweden)

    Zdzisław Kaliniewicz

    2018-02-01

    Full Text Available Scarification involves the partial removal of the seed coat on the side of the hilum, opposite the radicle, to speed up germination in acorns. The aim of this study was to determine the influence of scarification on the germination capacity of pedunculate oak acorns, selected and prepared for sowing. The diameter, length and mass of acorns were measured before and after scarification in four batches of acorns harvested from uneven-aged trees (76, 91, 131 and 161 years. The measured parameters were used to determine the correlations between acorn dimensions and mass, and to calculate the dimensional scarification index and the mass scarification index in acorns. Individual complete and scarified acorns from every batch were germinated on sand and peat substrate for 28 days. The analyzed acorns were characterized by average size and mass. Scarification decreased acorn mass by around 22% and acorn length by around 31% on average. Scarification and the elimination of infected acorns increased germination capacity from around 64% to around 81% on average. Acorns can be divided into size groups before scarification to obtain seed material with varied germination capacity. Larger acorns with higher germination capacity can be used for sowing in container nurseries, whereas smaller acorns with lower germination capacity can be sown in open-field nurseries.

  2. Oak (Quercus frainetto Ten.) honeydew honey--approach to screening of volatile organic composition and antioxidant capacity (DPPH and FRAP assay).

    Science.gov (United States)

    Jerković, Igor; Marijanović, Zvonimir

    2010-05-25

    Two samples of oak honeydew honey were investigated. Headspace solid-phase microextraction (HS-SPME) combined with GC and GC/MS enabled identification of the most volatile organic headspace compounds being dominated by terpenes(mainly cis- and trans-linalool oxides). The volatile and less-volatile organic composition of the samples was obtained by ultrasonic assisted extraction (USE) with two solvents (1:2 (v/v) pentane -diethyl ether mixture and dichloromethane) followed by GC and GC/MS analysis. Shikimic pathway derivatives are of particular interest with respect to the botanical origin of honey and the most abundant was phenylacetic acid (up to 16.4%). Antiradical activity (DPPH assay) of the honeydew samples was 4.5 and 5.1 mmol TEAC/kg. Ultrasonic solvent extracts showed several dozen times higher antiradical capacity in comparison to the honeydew. Antioxidant capacity (FRAP assay) of honeydew samples was 4.8 and 16.1 mmol Fe(2+)/kg, while the solvent mixture extracts showed antioxidant activity of 374.5 and 955.9 Fe(2+)/kg, respectively, and the dichloromethane extracts 127.3 and 101.5 mmol Fe(2+)/kg.

  3. Oak (Quercus frainetto Ten. Honeydew Honey—Approach to Screening of Volatile Organic Composition and Antioxidant Capacity (DPPH and FRAP Assay

    Directory of Open Access Journals (Sweden)

    Igor Jerković

    2010-05-01

    Full Text Available Two samples of oak honeydew honey were investigated. Headspace solid-phase microextraction (HS-SPME combined with GC and GC/MS enabled identification of the most volatile organic headspace compounds being dominated by terpenes(mainly cis- and trans-linalool oxides. The volatile and less-volatile organic composition of the samples was obtained by ultrasonic assisted extraction (USE with two solvents (1:2 (v/v pentane -diethyl ether mixture and dichloromethane followed by GC and GC/MS analysis. Shikimic pathway derivatives are of particular interest with respect to the botanical origin of honey and the most abundant was phenylacetic acid (up to 16.4%. Antiradical activity (DPPH assay of the honeydew samples was 4.5 and 5.1 mmol TEAC/kg. Ultrasonic solvent extracts showed several dozen times higher antiradical capacity in comparison to the honeydew. Antioxidant capacity (FRAP assay of honeydew samples was 4.8 and 16.1 mmol Fe2+/kg, while the solvent mixture extracts showed antioxidant activity of 374.5 and 955.9 Fe2+/kg, respectively, and the dichloromethane extracts 127.3 and 101.5 mmol Fe2+/kg.

  4. The Hibernation of the oak Mildew

    NARCIS (Netherlands)

    Kerling, L.C.P.

    1966-01-01

    The oak mildew invaded Western Europa in the years 1908 and 1909. Since then this parasite, Microsphaera alphitoides Griff. & Maubl. (syn. M. quercina (Schw.) Burr.) has occurred regularly in the Netherlands on oak seedlings and oak coppice, mainly Quercus pedunculata Ehr. (syn. Q. robur L. ). After

  5. Fragmentation patterns of evergreen oak woodlands in Southwestern Iberia

    DEFF Research Database (Denmark)

    Costa, A.; Madeira, M.; Lima Santos, J.

    2014-01-01

    Mediterranean evergreen oak woodlands (composed of Quercus suber L. and Quercus rotundifolia Lam.) are becoming increasingly fragmented in the human-modified landscapes of Southwestern Portugal and Spain. Previous studies have largely neglected to assess the spatial changes of oak woodlands...

  6. Effect of acorn moisture content at sowing on germination and seedling growth of white oak and northern red oak

    Science.gov (United States)

    Shi-Jean Susana Sung; Paul P. Kormanik; Catharine D. Cook; Stanley J. Zarnoch; Taryn L. Kormanik

    2006-01-01

    White oak (Quercus alba L.) and northern red oak (Q. rubra L.) acorns were collected locally or from seed orchards in October 2002. Mean acorn moisture content (MC) was 48 percent for white oak and 39 percent for northern red oak. These acorns were air dried to different MCs before being sown into nursery beds in early December...

  7. Effects of Flood Duration and Depth on Germination of Cherrybark, Post, Southern, White and Willow Oak Acorns

    Science.gov (United States)

    Yanfei Guo; Michael G. Shelton; Eric Heitzman

    2002-01-01

    Effects of flood duration (0, 10, 20, and 30 days) and depth (10 and 100 centimeters below a water surface) on acorn germination were tested for two bottomland oaks (cherrybark oak [Quercus pagoda Raf.] and willow oak [Q. phellos L.]) and three upland oaks (post oak [Q. stellata Wang.], southern red oak [

  8. Land-use legacies in the forest structure of silvopastoral oak woodlands in the Eastern Mediterranean

    OpenAIRE

    Plieninger, Tobias; Schaich, Harald; Kizos, Thanasis

    2013-01-01

    Eastern Mediterranean silvopastoral oak woodlands have been greatly damaged through forest conversion, illegal lumbering, overgrazing, and forest fires. The aim of this study was to assess land-use changes and the legacies that they have imprinted on the forest structure of Quercus macrolepis and accompanying Quercus pubescens and Quercus cerris woodlands on Lesvos Island, Greece. The size-structures of adult oak populations were analyzed as indicators of long-term oak regeneration, while sho...

  9. Pollen morphology of Quercus (subgenus Quercus, section Quercus in Iran and its systematic implication

    Directory of Open Access Journals (Sweden)

    Parisa Panahi

    2012-03-01

    Full Text Available For the first time, pollen morphology of 9 (4 spp. and 5 subspp. taxa representing lobed leaved oaks of Iran in the family of Fagaceae has been examined and illustrated using light microscopy and scanning electron microscopy of acetolysed material. Detailed pollen morphological characteristics are given for Quercus section. The pollen grains are single, isopolar, radially symmetrical, tricolpate, tricolporoidate or tricolporate. Pollens were studied to show all possible characteristics like shape, size, apertures, wall thickness, etc., with special reference to the specific features of each pollen type such as structural, sculptural and suprasculptural patterns. There is considerable variation in pollen morphology between taxa so that, three types of pollen shape, five types of structural pattern, two types of sculptural pattern, five types of suprasculptural pattern and three types of perfora distribution are defined. Furthermore, the relationship between pollen morphology and taxonomy is discussed. Overall, pollen characters are shown to be a useful and informative tool for assessing taxonomic position within Quercus section in Iran.

  10. Is deciduousness a key to climate resilience among iconic California savanna oak species? Relating phenological habits to seasonal indicators of tree physiological and water stress across field, hyperspectral, drone (UAS)-based multispectral and thermal image data

    Science.gov (United States)

    Mayes, M. T.; Caylor, K. K.; Ehlmann, B. L.; Greenberger, R. N.; Estes, L. D.

    2017-12-01

    In California (CA) savannas, oak trees (genus Quercus) play keystone roles in water and nutrient cycling, support biodiversity and many land-use activities. Declines in oak basal area of up to 25% from the 1930s-2000s, which have occurred alongside climate trends such as increasing variability of rainfall and prevalence of hotter droughts, threaten the services and ecological functions these trees provide. It is particularly unclear how climate relates to productivity and stress across oak species. Past work has found that seedling recruitment has varied inversely with "deciduousness." That is, evergreen oaks (e.g. Quercus agrifola. Coast Live Oak) are reproducing more successfully than drought-deciduous (e.g. Quercus douglassi, Blue Oak), which in turn are more successful than fully deciduous species (e.g. Quercus lobata, Valley Oak). However, there is poor understanding of how these ecological trends by species, corresponding with phenological habit, relate to physiological and ecohydrological processes such as carbon assimilation, water or nutrient use efficiency in mature tree stands. This limits predictive capability for which species will be most resilient to harsher future growing conditions, and, how to monitor stress and productivity in long-lived mature oak communities across landscapes via tools including remotely sensed data. This project explores how ecophysiological variables (e.g. stomatal conductance) relate to phenological habits across three oak species (Coast Live, Blue and Valley) over a seasonal dry-down period in Santa Barbara County, CA. Our goal is to probe if deciduousness is a key to resilience in productivity and water stress across iconic oak species. We test relationships between leaf and canopy-level field data, and indicators from multiple new sources of remotely sensed data, including ground hyperspectral, drone (UAS)-based multi-spectral and thermal image data, as means of monitoring tree physiological and water stress from scales

  11. Maximum crown area equation for open-grown bur oak

    Science.gov (United States)

    M.C. Demchik; S.M. Virden; Z.L. Buchanan; A.M. Johnson

    2017-01-01

    Bur oak (Quercus macrocarpa Michx.) is a classic savanna species with a range that covers much of the eastern United States. Because savannas are an endangered habitat in North America, significant restoration efforts are in progress across much of the range of bur oak. For open sites being planted with bur oaks as well as fully stocked sites that...

  12. Managing an oak decline crisis in Oakville, Ontario: lessons learned

    Science.gov (United States)

    Peter A. Williams; John W. McNeil; Kurt W. Gottschalk; Robert A. Haack

    2013-01-01

    The town of Oakville, Ontario, is located along the north shore of Lake Ontario between Toronto and Hamilton. In the fall of 2002, significant oak (Quercus spp.) mortality was observed at Oakville's Iroquois Shoreline Woods Park, an environmentally significant forest remnant noted for its oak-dominated forests. Investigations suggested that oak...

  13. A meta-analysis of the fire-oak hypothesis: Does prescribed burning promote oak reproduction in eastern North America

    Science.gov (United States)

    Patrick H. Brose; Daniel C. Dey; Ross J. Phillips; Thomas A. Waldrop

    2013-01-01

    The fire-oak hypothesis asserts that the current lack of fire is a reason behind the widespread oak (Quercus spp.) regeneration difficulties of eastern North America, and use of prescribed burning can help solve this problem. We performed a meta-analysis on the data from 32 prescribed fire studies conducted in mixed-oak forests to test whether they...

  14. An ecologically based approach to oak silviculture: a synthesis of 50 years of oak ecosystem research in North America

    Science.gov (United States)

    Daniel C. Dey; Alejandro A. Royo; Patrick H. Brose; Todd F. Hutchinson; Martin A. Spetich; Scott H. Stoleson

    2010-01-01

    Oak (Quercus L.) is an abundant and widely distributed genus in eastern North America. A history of periodic fire, grazing, canopy disturbance and timber harvesting has favored oak's dominance. But, changes in this regime toward much less fire or complete fire suppression, and selective cutting are causing the successional replacement of oak....

  15. Agrilus auroguttatus (Coleoptera: Buprestidae) seasonal development within Quercus agrifolia (Fagales: Fagaceae) in southern California

    Science.gov (United States)

    L.J. Haavik; T.W. Coleman; M.L. Flint; R.C. Venette; S.J. Seybold

    2013-01-01

    We investigated seasonal development of the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and physical conditions of the phloem within a preferred host species, coast live oak, Quercus agrifolia Née. We sampled infested trees on a monthly basis at two sites in southern California throughout...

  16. Cork oak woodlands patchiness

    DEFF Research Database (Denmark)

    Costa, Augusta; Madeira, Manuel; Plieninger, Tobias

    2014-01-01

    The cork oak (Quercus suber L.) woodlands of the agroforestry landscapes of Southwestern Iberia are undergoing drastic change due to severe natural and anthropogenic disturbances. These may eventually result in woodland loss or deforestation, the final step of an ongoing process of woodland...... woodlands exhibited similar trends of decreasing fractional canopy cover and decreasing number of larger patches. Patchiness rather than fractional canopy cover seems, however, to be potentially more useful as a signature of imminent oak woodlands deforestation, given that its contrast before and after...

  17. Ecology and management of oak woodlands and savannas in the southwestern Borderlands Region

    Science.gov (United States)

    Gerald J. Gottfried; Peter F. Ffolliott

    2013-01-01

    Management of the Madrean oak woodlands and the less dense and ecologically different oak savannas must be based on sound ecological information. However, relatively little is known about the Madrean oak ecosystems in spite of the fact that they cover about 80,000 km2 in the southwestern United States and northern Mexico. Emory oak (Quercus emoryi), the dominant tree...

  18. Modeling and mapping oak advance reproduction density using soil and site variables

    Science.gov (United States)

    John M. Kabrick; Jason L. Villwock; Daniel C. Dey; Tara L. Keyser; David R. Larsen

    2014-01-01

    Regenerating oaks (Quercus spp.) has remained a widespread and persistent problem throughout their natural range. Research shows that abundant oak advance reproduction is crucial for success. Although it is recognized that oak advance reproduction accumulation is inversely related to site quality, there has been little effort to model oak advance...

  19. Armillaria root disease affects oak coppice regeneration in upland Missouri Ozark forests

    Science.gov (United States)

    J. N. Bruhn; D. C. Dey; K. K. Kromroy; J. D. Mihail; J. M. Kabrick; J. J., Jr. Wetteroff

    2005-01-01

    Coppice regeneration is favored in North America for oak (Quercus spp.) regeneration. Although models of oak stump sprouting do not consider Armillaria root disease, many oak stumps in upland Ozark forest stands carry active Armillaria root crown infections. The spatial pattern of sprouting on oak stumps is...

  20. Diagnosis and Management of Phytophthora ramorum canker in canyon live oak, an atypical bole canker host

    Science.gov (United States)

    Tedmund J. Swiecki; Elizabeth Bernhardt; Kamyar Aram; David Rizzo

    2013-01-01

    Diagnosis of sudden oak death (SOD) in tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh) and susceptible red/black oak species (coast live oak, Quercus agrifolia Née; Shreve oak, Q. parvula Greene var. shrevei (C.H. Mull.) Nixon; California...

  1. Forecasting the future of coast live oak forests in the face of sudden oak death

    Science.gov (United States)

    Letty B. Brown; Barbara Allen-Diaz

    2006-01-01

    Little is known about the potential short- and long-term impacts of sudden oak death (SOD) on forest structure and composition. This study began in 2002 to evaluate the effects of SOD on coast live oak (Quercus agrifolia) - California bay laurel (Umbellularia californica) forests over a gradient of Phytophthora ramorum...

  2. Effect of phosphate treatments on sudden oak death in tanoak and Shreve's oak

    Science.gov (United States)

    Doug Schmidt; Matteo Garbelotto; Dave Chambers; Steve Tjosvold

    2006-01-01

    Field experiments were conducted to evaluate the effectiveness of phosphonate chemical treatments for control of sudden oak death in tanoak (Lithocarpus densiflorus) and Shreve's oak (Quercus parvula var. Shrevei). Native stands of mature trees were preventatively treated with Agrifos® systemic fungicide and...

  3. Amplification of North American Red Oak Microsatellite Markers in European White Oaks and Chinese Chestnut

    Science.gov (United States)

    P. R. Aldrich; M. Jagtap; C. H. Michler; J. Romero-Severson

    2003-01-01

    We examined the cross-species amplification success of thirty microsatellite markers developed from North American northern red oak (Quercus rubra) in other members of the family Fagaceae. Sixteen of these markers are newly developed and we report primer sequences and amplification conditions here. Twelve of the thirty (40.0%) red oak markers...

  4. The Physiology and Biochemistry of Desiccating White Oak and Cherrybark Oak Acorns

    Science.gov (United States)

    Kristina F. Connor; Sharon Sowa

    2004-01-01

    The recalcitrant behavior of white oak (Quercus alba L.) and cherrybark oak (Q. pagoda Raf.) acorns was examined in terms of effects of moisture content on seed longevity, viability, and biochemistry. Acorns of both species were fully hydrated and then subjected to drying under ambient conditions of temperature and relative...

  5. Establishment patterns of Oregon white oak and California black oak woodlands in northwestern California

    Science.gov (United States)

    Madelinn Schriver; Rosemary Sherriff

    2015-01-01

    Mixed-Oregon white oak (Quercus garryana) and California black oak (Q. kelloggii) woodlands are unique ecosystems that support high biodiversity in the Pacific Northwest, yet little is known about their current and historical stand establishment patterns in northwestern California. With concerns of local extirpation due to...

  6. Soil properties and understory herbaceous biomass in forests of three species of Quercus in Northeast Portugal

    Directory of Open Access Journals (Sweden)

    Marina Castro

    2014-12-01

    Full Text Available Aim of study: This paper aims to characterize some soil properties within the first 25 cm of the soil profile and the herbaceous biomass in Quercus forests, and the possible relationships between soil properties and understory standing biomass.Area of study: Three monoespecific Quercus forests (Q. suber L., Q. ilex subsp. rotundifolia Lam. and Q. pyrenaica Willd in NE Portugal.Material and methods: During 1999 and 2000 soil properties (pH-KCl, total soil nitrogen (N, soil organic carbon (SOC, C/N ratio, available phosphorus (P, and available potassium (K and herbaceous biomass production of three forest types: Quercus suber L., Quercus ilex subsp. rotundifolia Lam. and Quercus pyrenaica Willd were studied.Main results: The results showed a different pattern of soil fertility (N, SOC, P, K in Quercus forests in NE of Portugal. The C/N ratio and the herbaceous biomass confirmed this pattern. Research highlights: There is a pattern of Quercus sp. distribution that correlates with different soil characteristics by soil characteristics in NE Portugal. Q. pyrenaica ecosystems were found in more favoured areas (mesic conditions; Q. rotundifolia developed in nutrient-poor soils (oligotrophic conditions; and Q. suber were found in intermediate zones.Keywords: fertility; biomass; C/N ratio; cork oak; holm oak; pyrenean oak.

  7. Effects of disking, bedding, and subsoiling on survival and growth of three oak species in central Mississippi

    Science.gov (United States)

    J. Paul Jeffreys; Emily B. Schultz; Thomas G. Matney; W. Cade Booth; Jason M. Morris

    2010-01-01

    A replicated split-plot design experiment to evaluate the effects of three site preparation methods (disking, bedding, and subsoiling plus bedding) on survival and growth of three oak species (cherrybark, Quercus pagoda Raf.; Shumard, Quercus shumardii Buckl.; and Nuttall, Quercus texana Buckl.) was established...

  8. Effects of drought and shade on growth and water use of Quercus alba, Q. bicolor, Q. imbricaria and Q. palustris seedlings

    Science.gov (United States)

    Joseph J. McCarthy; Jeffrey O. Dawson

    1991-01-01

    Growth and water use efficiency were determined for 2-year-old white oak (Quercus alba), swamp white oak (Q. imbricaria) and pin oak (Q. palustris) seedlings grown under three shade treatments (30, 55 and 73%) and two irrigation regimes (container capacity and mild drought). With species and water regimes...

  9. Effects of soil compaction, forest leaf litter and nitrogen fertilizer on two oak species and microbial activity

    Science.gov (United States)

    D. Jordan; F., Jr. Ponder; V. C. Hubbard

    2003-01-01

    A greenhouse study examined the effects of soil compaction and forest leaf litter on the growth and nitrogen (N) uptake and recovery of red oak (Quercus rubra L.) and scarlet oak (Quercus coccinea Muencch) seedlings and selected microbial activity over a 6-month period. The experiment had a randomized complete block design with...

  10. Attack pattern of Platypus koryoensis (Coleoptera: Curculionidae: Platypodidae) in relation to crown dieback of Mongolian oak in Korea

    Science.gov (United States)

    Jung-Su Lee; Robert A. Haack; Won Il. Choi

    2011-01-01

    The ambrosia beetle, Platypus koryoensis (Murayama), vectors the Korean oak wilt (KOW) pathogen, Raffaelea quercus-mongolicae K.H. Kim, Y.J. Choi, & H.D. Shin, in Korea, which is highly lethal to Mongolian oak, Quercus mongolica Fisch., and is considered a major threat to forest ecosystem health. We...

  11. Field test of foliar-spray herbicides to control mountain laurel in mature mixed-oak forests in western Maryland

    Science.gov (United States)

    Gary W. Miller; Patrick H. Brose; Jeffrey D. Kochenderfer; James N. Kochenderfer; Kurt W. Gottschalk; John R. Denning

    2016-01-01

    Successful oak (Quercus spp.) regeneration requires the presence of competitive sources of oak reproduction before parent oaks are harvested. Mountain laurel (Kalmia latifolia) in the understory of many Appalachian forests prevents new oak seedlings from receiving adequate sunlight to survive and grow into competitive size classes. This study examined the efficacy of...

  12. Single-tree harvesting reduces survival and growth of oak stump sprouts in the Missouri Ozark Highlands

    Science.gov (United States)

    Daniel C. Dey; Randy G. Jensen; Michael J. Wallendorf

    2008-01-01

    Regeneration and recruitment into the overstory is critical to the success of using uneven-aged systems to sustain oak forests. We evaluated survival and growth of white oak (Quercus alba L.), black oak (Q. velutina Lam.), and scarlet oak (Q. coccinea Muenchh.) stump sprouts 10 years after harvesting Ozark...

  13. Effects of flood duration and season on germination of black, cherrybark, northern red, and water oak acorns

    Science.gov (United States)

    Yanfei Guo; Michael G. Shelton; Brian R. Lockhart

    1998-01-01

    Effects of flood duration (0, 10, 20, and 30 days) and season (winter and spring) on acorn germination were tested for two upland oaks [black and northern red oak (Quercus velutina Lam. and Q. rubra L.)] and two bottomland oaks [cherrybark and water oak (Q. pagoda Raf. and Q. nigra L.)]. Acorns...

  14. Impact of the goldspotted oak borer, Agrilus auroguttatus, on the health of coast live oak before and after treatment with two systemic insecticides

    Science.gov (United States)

    Yigen Chen; Mary L. Flint; Tom W. Coleman; Joseph J. Doccola; Donald M. Grosman; David L. Wood; Steven J. Seybold

    2015-01-01

    BACKGROUND: The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego County, California. From two sites in the core area of the infestation, we report a 2.5 year investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic...

  15. Biología reproductiva y conservación: el caso de la regeneración de bosques templados y subtropicales de robles (Quercus spp. Plant reproductive biology and conservation: the case of temperate and subtropical oak forest regeneration

    Directory of Open Access Journals (Sweden)

    Fernando J. Pulido

    2002-03-01

    Full Text Available En este trabajo se revisan los resultados de 21 estudios experimentales sobre la regeneración de bosques de roble (Quercus spp. en los que se analizan al menos tres de las fases del ciclo reproductivo: fertilización, desarrollo de frutos viables, dispersión, consumo postdispersivo, germinación-emergencia de plántulas, establecimiento de juveniles y reclutamiento de adultos. La mayoría de las poblaciones estudiadas se encontraban en bosques templados de Norteamérica y Europa, repartidos de forma equitativa entre bosques de ambientes xéricos (incluidos los mediterráneos con especies perennes y habitualmente bajo explotación, y bosques de ambientes mésicos o montanos con especies generalmente caducifolias y escasamente alterados. Los estudios se clasificaron de acuerdo con los tipos de limitación de la regeneración encontrados por los autores, esto es, producción de semillas viables, presión de herbívoros y disponibilidad de sitios seguros. La revisión muestra que en la mayoría de los casos la regeneración se encontraba limitada por una combinación de factores, típicamente el consumo de bellotas y un ambiente abiótico desfavorable durante el establecimiento. La fecundidad de los árboles ha sido rara vez estudiada a pesar de que puede llegar ser en una limitación frecuente, al igual que ocurre con las limitaciones de la dispersión por animales. Finalmente, se analiza el grado de aplicación de la información ecológica acumulada a la solución de problemas de regeneración natural, y se discute su utilidad en comparación con las prácticas más comunes de regeneración artificial via plantacionesThis study presents a review of 21 experimental studies on oak (Quercus regeneration analysing at least three phases of the reproductive cycle, namely fertilization, viable fruit production, acorn dispersal, postdispersal predation, seedling emergence, sapling establishment, and adult recruitment. Most study cases came from North

  16. Acorn storage alternatives tested on Oregon white oak

    Science.gov (United States)

    Warren D. Devine; Constance A. Harrington; Joseph M. Kraft

    2010-01-01

    We assessed various combinations of storage factors: bag type, temperature, duration, and antifungal pre-storage treatments for white oak acorn storage, using Oregon white oak (Quercus garryana Douglas ex Hook. [Fagaceae]) acorns from 7 seed sources. Acorn viability remained high (84%), even after 2 y of refrigerated storage, but the majority of...

  17. Genetic hitch-hiking extends the range of coast live oak

    Science.gov (United States)

    Richard S. Dodd; Zara Afzal-Rafii; Wasima Mayer

    2006-01-01

    The northernmost range of coast live oak (Quercus agrifolia) is reported from the Ukiah Valley (Mendocino County, California). Here, field observations suggest that hybridization with interior live oak (Q. wislizeni) is important. Elsewhere in northern California, morphology of coast live oak can be highly variable (particularly...

  18. Dendrochronological analysis of white oak growth patterns across a topographic moisture gradient in southern Ohio

    Science.gov (United States)

    Alexander K. Anning; Darrin L. Rubino; Elaine K. Sutherland; Brian C. McCarthy

    2013-01-01

    Moisture availability is a key factor that influences white oak (Quercus alba L.) growth and wood production. In unglaciated eastern North America, available soil moisture varies greatly along topographic and edaphic gradients. This study was aimed at determining the effects of soil moisture variability and macroclimate on white oak growth in mixed-oak forests of...

  19. Biomarkers identify coast live oaks that are resistant to the invasive pathogen Phytophthora ramorum

    Science.gov (United States)

    Brice A. McPherson; Sylvia R. Mori; Anna O. Conrad; Stephen Opiyo; Pierluigi Bonello; David L. Wood

    2015-01-01

    California coast live oaks (Quercus agrifolia) trees have suffered large losses from sudden oak death, caused by the introduced oomycete Phytophthora ramorum. In this review paper, we discuss oak plant chemistry as a potential predictor of disease susceptibility. We have recorded an annual mortality rate of three percent in...

  20. Ten-year response of competing vegetation after oak shelterwood treatments in West Virginia

    Science.gov (United States)

    Gary W. Miller; James N. Kochenderfer; Jeffrey D. Kochenderfer; Kurt W. Gottschalk

    2014-01-01

    Successful oak regeneration depends on the relative status of advanced oak reproduction and associated competing woody vegetation present when harvests or other stand-replacing disturbances occur. This study was installed to quantify the effect of microsite light availability and deer browsing on the development of advanced northern red oak (Quercus rubra...

  1. Ten-year results of using oak Cleanings to maintain oak species dominance on the Allegheny National Forest

    Science.gov (United States)

    Kurt W. Gottschalk; Gary W. Miller; Robert White; Andrea Hille; Thomas M. Schuler

    2014-01-01

    The Allegheny National Forest (ANF) in northwestern Pennsylvania implemented precommercial thinning in young stands to maintain oak (Quercus spp.) stems in a competitive position. This administrative study was developed to test ANF standards for precommercial thinning for success in maintaining oak composition. An additional objective was to examine...

  2. Air pollution effects on Quercus Ilex plants

    International Nuclear Information System (INIS)

    Pavone, P.; Salmeri, C.; Spampinato, G.; Fallico, R.; Ferrante, M.

    1996-01-01

    To test air pollution effects on natural forest vegetation, the soil chemistry and the floristic composition of two Quercus ilex L. woods in the Hyblean region (S-E Sicily), unequally exposed to air pollutants are compared. Acidification phenomena are investigated by the soil chemical changes between the trunk base areas, affected by stem flow water, and the surrounding soil, only influenced by canopy drip. Soil chemical changes, floristic poorness and direct damage to the Q. ilex leaves are only detected in the Climiti Mountains holm-oak woods, located near the Siracusa petrochemical complex, while they do not appear at Cava d'Ispica, sited far from any industry and seldom exposed to winds carrying pollutants

  3. Oak Decline

    Science.gov (United States)

    Philip M. Wargo; David R. Houston; Leon A. LaMadeleine

    1983-01-01

    Periodic occurrences of decline and death of oaks over widespread areas have been recorded since 1900. These outbreaks, variously named oak decline, oak dieback, or oak mortality, are caused by a complex interaction of environmental stresses and pests and given the name oak decline.

  4. y Quercus laurina

    Directory of Open Access Journals (Sweden)

    R. Flores-Velázquez

    2007-01-01

    Full Text Available Se determinaron las características de maquinado con base en la norma ASTM D 1666-87, en las operaciones de cepillado, barrenado, moldurado, torneado y lijado de la madera de Quercus affinis y Quercus laurina. Los mejores resultados de cepillado para Q. affinis se encontraron al combinar el ángulo de corte de 15º y una velocidad de alimentación de 7.5 m·min-1, para Q. laurina no hubo influencia del ángulo de corte. En el barrenado se obtuvieron excelentes resultados con las dos velocidades de giro de broca probadas. Para el moldurado, los resultados para las dos especies fueron excelentes en ambos cortes. En el torneado se encontró que no existe influencia del contenido de humedad para Q. laurina, mientras que para Q. affinis se clasificó como buena para un contenido de humedad menor y excelente para el mayor contenido de humedad. Y para el lijado los resultados fueron excelentes. De acuerdo a los resultados de las pruebas, las dos especies son apropiadas para ser utilizadas por la industria maderera para la elaboración de productos terminados de alta calidad.

  5. Mercury Distribution and Seasonal and Inter annual Variation of Mercury in Oak (Quercus ilex L.) in Almadenejos (Ciudad Real, Spain); Distribucion y Variacion Estacional e Interanual de Mercurio en La Encina (Quercus ilex L.) en el Municipio de Almadenejos (Ciudad Real)

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Alonso, J.; Sierra, M. J.; Millan, R.

    2014-10-01

    Plants that are exposed to environmental pollutants are able to accumulate them in their organs depending on plant species, type of organ or age among others. Evergreen plants can hold stems and leaves of the different age over the same branch. Thus, the amount of contaminants of these former organs could vary with its age because the contamination exposure time is different. The aim of this study is to know in a tree species, the mercury (Hg) distribution in it and the variation of Hg concentration in leaves and stems between consecutive years and along the same year. In order to carry this objective out, three different trees of Quercus ilex L. were selected and two branches were taken from each of them. Such trees are located in Almadenejos, a village from the Almaden mining district (Ciudad Real, Spain), an area well known due to the developed Hg mining activities for centuries. Considering each branch and each year, on average the results show that leaves had higher Hg concentration than stems. Furthermore, the lowest Hg concentration was measured in fruit (acorn). With regard to ageing effect on Hg concentration and taking into account each branch separately, the results show that the older leaves had higher Hg concentration than younger ones. Nevertheless, the oldest stems had not always higher Hg concentration than youngest ones. A seasonal variation in Hg content appeared both in leaves and in stems in 2010, increasing in 6.2 times on average, in about six months. This result suggests that this kind of organs should be analyzed in winter months. Finally, the results show a very high positive correlation between the Hg of the bark and the Hg of the wood in the sampled branches. Such result suggests that if bark is sampled and its Hg content is analyzed, we could know the Hg content in the big branches or in the trunk, avoiding the cutting of the branches or the whole tree. (Author)

  6. Competitive capacity of Quercus rubra L. planted in Arkansas' Boston Mountains

    Science.gov (United States)

    Martin A. Spetich; Daniel C. Dey; Paul S. Johnson; David L. Graney

    2002-01-01

    Results of an 11 yr study of the growth and survival of planted northern red oak (Quercus rubra L.) seedlings (2-0 bare-root) are presented. More than 4,000 seedlings were planted under shelterwood overstories that were harvested 3 yr after planting. Results are expressed as planted-tree dominance probabilities. Dominance probability is the...

  7. Effects of moisture and nitrogen stress on gas exchange and nutrient resorption in Quercus rubra seedlings

    Science.gov (United States)

    K. Francis Salifu; Douglass F. Jacobs

    2008-01-01

    The effects of simulated soil fertility at three levels (poor, medium, and rich soils) and moisture stress at two levels (well watered versus moisture stressed) on gas exchange and foliar nutrient resorption in 1+0 bareroot northern red oak (Quercus rubra) seedlings were evaluated. Current nitrogen (N) uptake was labeled with the stable isotope

  8. Isolation and characterization of repeat elements of the oak genome and their application in population analysis

    International Nuclear Information System (INIS)

    Fluch, S.; Burg, K.

    1998-01-01

    Four minisatellite sequence elements have been identified and isolated from the genome of the oak species Quercus petraea and Quercus robur. Minisatellites 1 and 2 are putative members of repeat families, while minisatellites 3 and 4 show repeat length variation among individuals of test populations. A 590 base pair (bp) long element has also been identified which reveals individual-specific autoradiographic patterns when used as probe in Southern hybridisations of genomic oak DNA. (author)

  9. Impacts of human-induced environmental disturbances on hybridization between two ecologically differentiated Californian oak species

    OpenAIRE

    Ortego, Joaquín; Gugger, Paul F.; Sork, Victoria L.

    2017-01-01

    Natural hybridization, which can be involved in local adaptation and in speciation processes, has been linked to different sources of anthropogenic disturbance. Here, we use genotypic data to study range-wide patterns of genetic admixture between the serpentine-soil specialist leather oak (Quercus durata) and the widespread Californian scrub oak (Quercus berberidifolia). First, we estimated hybridization rates and the direction of gene flow. Second, we tested the hypothesis that genetic ad...

  10. The Insect Guild of White Oak Acorns: Its Effect on Mast Quality in the Ozark and Ouachita National Forests

    Science.gov (United States)

    Alex C. Mangini; Roger W. Perry

    2004-01-01

    Abstract - Hardwood regeneration, especially of oaks, is an essential component of ecosystem management in the Ouachita and Ozark Mountains of Arkansas. In addition, oak mast is an important wildlife food. Several species of insects inhabit and consume acorns. Data on the insect guild inhabiting white oak (Quercus alba L.) acorns...

  11. New Approach for Differentiating Sessile and Pedunculate Oak: Development of a LC-HRMS Method To Quantitate Triterpenoids in Wood.

    Science.gov (United States)

    Marchal, Axel; Prida, Andréi; Dubourdieu, Denis

    2016-01-27

    Oak aging is a crucial step in winemaking during which the organoleptic properties of wine are modified. Various parameters affect the chemical composition of oak wood including botanical origin, which has been previously shown to be a determinant factor. This study focused on the development of a LC-HRMS method to assay four recently discovered taste-active triterpenes (three sweet and one bitter). The method was applied to evaluate the effect of oak species (Quercus petraea and Quercus robur) on the concentration of these molecules in wood. The results showed that sessile oak was richer in sweet triterpenes and poorer in the bitter one than pedunculate oak, with high interindividual variations within species. Furthermore, a triterpenoid index was calculated to reveal the triterpenoid composition of oak wood. This index appears to be a promising tool for the unambiguous discrimination of oak species and could offer new insights into oak wood selection by coopers and the monitoring of oak aging by winemakers.

  12. Embryogenesis in Oak species. A review

    Directory of Open Access Journals (Sweden)

    Aranzazu Gomez-Garay

    2014-08-01

    Full Text Available Aim of study: A review on the propagation methods of four Quercus species, namely Q. suber, Q. robur, Q. ilex and Q. canariensis, through somatic embryogenesis and anther embryogenesis are presented.Area of study: The study comprises both Mediterranean and Atlantic oak species located in Spain.Material and Methods: Somatic embryogenesis was induced on immature zygotic embryos of diverse oak species, permitting the multiplication of half-sib families. Induction of haploid embryos and doubled haploids was assayed in both Q. suber and Q. ilex by temperature stress treatments of anthers containing late vacuolated microspores. The haploid origin of the anther embryos has been evaluated by quantitative nuclear DNA analysis through flow cytometry and by DNA microsatellite markers. Genetic transformation of cork oak has also been performed by means of Agrobacterium tumefaciens vectors. Proteomic analysis has been conducted to screen the diverse protein profiles followed by in vitro derived embryos during their development.Research highlights: Successful plant regeneration from both somatic and haploid embryos has been achieved. In the particular case of cork oak, doubled-haploid plants were obtained. Plantlets regenerated from selected parent trees through somatic embryogenesis were acclimated in the greenhouse and in the nursery, and were planted in an experimental plot in the field. Preliminary evaluation of the cork quality of the plants showed a good heritability correlation with the parent trees. This article revises the work of and is dedicated to Dr. M.A. Bueno, who devoted much of her professional life to the research on Biotechnology and Genetics of forest species, leading the Laboratory of Forest Biotechnology at the Spanish Institute of Agronomic Research (INIA.Key words: anther embryogenesis; microspore; pollen; Quercus canariensis; Quercus ilex; Quercus robur; Quercus suber; somatic embryogenesis. 

  13. The most significant fungi: Agents of wood decay in oak forests of Serbia

    Directory of Open Access Journals (Sweden)

    Milijašević Tanja

    2007-01-01

    Full Text Available The most widely distributed oak species in Serbia are Q. petrea (sessile oak, Q. cerris (Turkey oak and Q. frainetto (Hungarian oak and Quercus robur (common oak, and lignicolous fungi are the major agents of wood decay in natural and coppice oak forests. In this research, 33 species of fungi were identified. Eleven species were described, among which the most significant are: Armillaria mellea, Fomes fomentarius, Hypoxylon deustum Laetiporus sulphureus, Lenzites quercina and Phellinus robustus. This paper presents the morphological characteristics of the most significant identified fungi, their distribution, host plants and significance.

  14. Continuous Spectrum LEDs Promote Seedling Quality Traits and Performance of Quercus ithaburensis var. macrolepis.

    Science.gov (United States)

    Smirnakou, Sonia; Ouzounis, Theoharis; Radoglou, Kalliopi M

    2017-01-01

    Regulation of the growth, development, and quality of plants by the control of light quality has attracted extensive attention worldwide. The aim of this study was to examine the effects of continuous LED spectrum for indoor plant pre-cultivation and to investigate the morphological and physiological responses of a common broadleaved tree species in Mediterranean environment, Quercus ithaburensis var. macrolepis at seedling developmental stage. Thus, the seedlings were pre-cultivated for 28 days, under five different LED light qualities: (1) Fluorescent (FL) as control light (2) L20AP67 (high in green and moderate in far-red), (3) AP673L (high in green and red), (4) G2 (highest in red and far-red), AP67 (high in blue, red, and far-red), and (5) NS1 (highest in blue and green and lowest in far-red) LEDs. Further examination was held at the nursery for 1 year, on several seedling quality traits. Indeed, AP67 and AP673L triggered higher leaf formation, while L20AP67 positively affected seedling shoot development. NS1 and AP67 LED pre-cultivated seedlings showed significantly higher root fibrosity than those of FL light. Furthermore, NS1 and AP673L LEDs induced fourfold increase on seedling root dry weight than FL light. Hence, evaluating the seedling nursery performance attributes, most of those photomorphogenetic responses previously obtained were still detectable. Even more so, LED pre-cultivated seedlings showed higher survival and faster growth indicating better adaptation even under natural light conditions, a fact further reinforced by the significantly higher Dickson's quality index acquired. In conclusion, the goal of each nursery management program is the production of high quality seedlings with those desirable traits, which in turn satisfy the specific needs for a particular reforestation site. Thus, the enhanced oak seedling quality traits formed under continuous LEDs spectrum especially of NS1 and AP673L pre-cultivation may potentially fulfill this goal.

  15. Sprouting productivity and allometric relationships of two oak species managed for traditional charcoal making in central Mexico.

    NARCIS (Netherlands)

    Aguilar, R.; Ghilardi, A.; Vega, E.; Skutsch, Margaret; Oyama, K.

    2012-01-01

    Sustainable production systems for woodfuels in developing countries require basic information on tree productivity, and particularly on their coppicing productivity under current forms of management. We report biomass equations and sprouting productivity of two oak species (Quercus castanea and

  16. Does the shelterwood method to regenerate oak forests affect acorn production and predation?

    Science.gov (United States)

    M.I. Bellocq; C. Jones; D.C. Dey; J.J. Turgeon

    2005-01-01

    The shelterwood system is one of the primary methods currently used to encourage regeneration of oak forests; yet, little is known about its influence on acorn production and predation. We compared acorn production, and predation by insects and mammals in stands of red oak (Quercus rubra L.) that were regenerated by the shelterwood method (50% canopy...

  17. Bat activity at remnant oak trees in California Central Coast vineyards

    Science.gov (United States)

    William D. Tietje; Ted Weller; Christopher C. Yim

    2015-01-01

    During 1990 to 2013, the area planted with wine grapes increased nearly 4.5 times in San Luis Obispo County. Much of this development occurred on open oak savanna with scattered oak (Quercus spp.) trees. Remnant trees are retained in some vineyards, but their value to biodiversity retention has not been quantified. During April to September 2014,...

  18. Anthropogenic fire history and red oak forests in south-central Ontario

    Science.gov (United States)

    Daniel C. Dey; Richard P. Guyette

    2000-01-01

    The regeneration and dominance of northern red oak (Quercus rubra L.) has been associated with fire throughout eastern North America. Red oak in central Ontario grows near the northern edge of its distribution in mixed hardwood - coniferous forests under mesic conditions where it competes with more shade-tolerant species. We hypothesized that the...

  19. Change in oak abundance in the eastern United States from 1980 to 2008

    Science.gov (United States)

    Songlin Fei; Ningning Kong; Kim C. Steiner; W. Keith Moser; Eric B. Steiner

    2011-01-01

    Although oaks (Quercus spp.) have historically dominated much of the forest land in eastern North America, a great deal of fragmentary and sometimes anecdotal evidence suggests that they have been yielding dominance in recent decades to other, typically more shade-tolerant species. Using FIA data, our work formally quantifies the change in oak abundance in the eastern...

  20. The temporal distribution and carbon storage of large oak wood in streams and floodplain deposits

    Science.gov (United States)

    Richard P. Guyette; Daniel C. Dey; Michael C. Stambaugh

    2008-01-01

    We used tree-ring dating and 14C dating to document the temporal distribution and carbon storage of oak (Quercus spp.) wood in trees recruited and buried by streams and floodplains in northern Missouri, USA. Frequency distributions indicated that oak wood has been accumulating in Midwest streams continually since at least the...

  1. Long-term effects of single prescribed fires on hardwood regeneration in oak shelterwood stands

    Science.gov (United States)

    Patrick H. Brose

    2010-01-01

    One of the arguments against using prescribed fire to regenerate oak (Quercus spp.) forests is that the improvement in species composition of the hardwood regeneration pool is temporary and multiple burns are necessary to achieve and maintain oak dominance. To explore this concern, I re-inventoried a prescribed fire study conducted in the mid-1990s...

  2. Evaluation of cleanings to maintain oak forests on the Allegheny National Forest

    Science.gov (United States)

    Kurt W. Gottschalk; Gary W. Miller; Robert L. White; Andrea Hille; Thomas M. Schuler

    2014-01-01

    Ten-year results for an administrative study on the Allegheny National Forest (ANF) that examined their cleaning (precommercial thinning) prescriptions and standards for success in maintaining oak (Quercus spp.) composition in young stands and maintaining oak stems in a competitive position are presented. Two studies were installed. One study was in...

  3. Northern red oak volume growth on four northern Wisconsin habitat types

    Science.gov (United States)

    Michael Demchik; Kevin M. Schwartz; Rory Braun; Eric. Scharenbrock

    2014-01-01

    Northern red oak (Quercus rubra) grows across much of Wisconsin. Using site factors to aid in prediction of volume and basal area increment facilitates management of red oak and other species of interest. Currently, habitat type (Wisconsin Habitat Type Classification System) is often determined when stands are inventoried. If habitat type were...

  4. Recent advances in the control of oak wilt in the United States

    Science.gov (United States)

    Dan A. Wilson

    2005-01-01

    Oak wilt, caused by Ceratocystis fagacearum (T.W.Bretz) J. Hunt, is probably the most destructive disease of oak trees (Quercus species) in the United States, and is currently causing high morality at epiphytotic proportions in central Texas. The serious potential for damage pro,pted an increase in federal funding within the past...

  5. A spatial statistical analysis of cork oak competition in two Portuguese silvopastoral systems

    NARCIS (Netherlands)

    Paulo, M.J.; Stein, A.; Tomé, M.

    2002-01-01

    This paper considers competition among cork oaks (Quercus suber L.) at three plots in two representative Portuguese stands. It uses spatial point pattern functions to describe densities and quantify differences among stands. Relations between cork oak characteristics and indices measuring intertree

  6. Pin oak acorn production and regeneration as affected by stand density, structure and flooding

    Science.gov (United States)

    Leon S. Minckler; Robert E. McDermott

    1960-01-01

    Pin oak (Quercus palustris Muench.) is an important tree species common on wet, heavy soils in the Central States region. Until recently, however, the silvics of this species has been neglected (Minckler, 1957). In an effort to provide some of the missing information, a study was begun several years ago to find our more about pin oak acorn production...

  7. Herbivory and the cycling of nitrogen and phosphorus in isolated California oak trees

    Science.gov (United States)

    David Y. Hollinger

    1986-01-01

    Nitrogen and phosphorus flow in litterfall and throughfall were studied in two California Quercus species (the evergreen Q.agrifolia and deciduous Q. lobata) before, during, and after an outbreak of the California oak moth, Phryganidia californica. All of the foliage of both oak species was...

  8. Phytophthora ramorum in coast live oak: search for resistance and mechanisms.

    Science.gov (United States)

    B.A. McPherson; D.L. Wood; S.R. Mori; A. Conrad; P. Bonello

    2013-01-01

    Despite the presence of Phytophthora ramorum in northern and central California forests since at least 1994, asymptomatic coast live oaks (Quercus agrifolia Née) still remain in heavily infested stands. Coast live oak infection and mortality rates of 5 percent y-1 and 3 percent y-1, respectively, observed in long-term...

  9. Is there evidence of mesophication of oak forests in the Missouri Ozarks?

    Science.gov (United States)

    Matthew G. Olson; Aaron P. Stevenson; Benjamin O. Knapp; John M. Kabrick; Randy G. Jensen

    2014-01-01

    Many studies on oak-dominated forests of the Central Hardwood region (CHR) have reported increasing abundance of fire-sensitive species and poor recruitment of oak (Quercus spp.) in the absence of frequent fire. However, most of these studies were conducted in the eastern and central CHR, and the assumption that similar dynamics occur in the western...

  10. Litter Species Composition and Topographic Effects on Fuels and Modeled Fire Behavior in an Oak-Hickory Forest in the Eastern USA

    Science.gov (United States)

    Matthew B. Dickinson; Todd F. Hutchinson; Mark Dietenberger; Frederick Matt; Matthew P. Peters; Jian Yang

    2016-01-01

    Mesophytic species (esp. Acer rubrum) are increasingly replacing oaks (Quercus spp.) in fire-suppressed, deciduous oak-hickory forests of the eastern US. A pivotal hypothesis is that fuel beds derived from mesophytic litter are less likely than beds derived from oak litter to carry a fire and, if they do, are more likely to...

  11. Twenty-nine years of development in planted cherrybark oak-sweetgum mixtures: implications for future mixed-species hardwood plantations

    Science.gov (United States)

    Brian Roy Lockhart; Andrew W. Ezell; John D. Hodges; Wayne K. Clatterbuck

    2012-01-01

    Results from a long-term planted mixture of cherrybark oak (Quercus pagoda Raf.) and sweetgum (Liquidambar styraciflua L.) showed sweetgum taller in height and larger in diameter than cherrybark oak early in plantation development. By age 17, cherrybark oak was similar in height and diameter with sweetgum and by age 21 was taller...

  12. Growth and Development of Outplanted High-Quality Northern Red Oak Seedlings and the Effects of Competing Herbaceous Productions Within Four Overstory Treatments -- First-Year Results

    Science.gov (United States)

    Christopher M. Oswalt; Wayne K. Clatterbuck; Scott E. Scharbaum; Allan E. Houston

    2004-01-01

    Historically, oak (Quercus spp .) regeneration success on highly productive hardwood sites can be described as highly variable. Research has shown that establishing large advance oak regeneration prior to overstory removal is neces-sary to maintain oak populations in future stands. However, experience indicates that forest landowners are typically...

  13. Physiological, anatomical, and ecological characteristics of southern live oak

    Science.gov (United States)

    Yadong Qi; Jammie Favorite; Kit L. Chin; Ying Xiao

    2006-01-01

    Gas exchanges of sun-exposed and shaded leaves of southern live oak (Quercus virginiana Mill.) were studied monthly from May to September, 2000. Six healthy live oak trees with d.b.h. ranging from 21 to 148 cm on Southern University’s campus in Baton Rouge, LA, were selected for the study. Instantaneous gas exchanges were measured during clear sky...

  14. Root desiccation and drought stress responses of bareroot Quercus rubra seedlings treated with a hydrophilic polymer root dip

    Science.gov (United States)

    Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese

    2009-01-01

    Root hydrogel, a hydrophilic polymer, has been used to improve transplanting success of bareroot conifer seedlings through effects on water holding capacity. We examined mechanisms by which Terra-sorb Fine Hydrogel reduces damage that occurs when roots of 1-year old, dormant northern red oak (Quercus rubra L.) were subjected to shortterm (1, 3, and 5...

  15. High-light acclimation in Quercus robur L.seedlings upon over-topped a shaded environment

    Science.gov (United States)

    Anna M. Jensen; Emile S. Gardiner; Kevin C. Vaughn

    2012-01-01

    High developmental plasticity at the seedling-level during acclimation to the light environment may be an important determinant of seedling establishment and growth in temperate broadleaf forests, especially in dense understories where spatial light availability can vary greatly. Pedunculate oak (Quercus robur L.) seedlings were raised beneath a...

  16. Field performance of Quercus bicolor established as repeatedly air-root-pruned container and bareroot planting stock

    Science.gov (United States)

    J.W." Jerry" Van Sambeek; Larry D. Godsey; William D. Walter; Harold E. Garrett; John P. Dwyer

    2016-01-01

    Benefits of repeated air-root-pruning of seedlings when stepping up to progressively larger containers include excellent lateral root distribution immediately below the root collar and an exceptionally fibrous root ball. To evaluate long-term field performance of repeatedly air-root-pruned container stock, three plantings of swamp white oak (Quercus bicolor...

  17. Container volume and subirrigation schedule influence Quercus variabilis seedling growth and nutrient status in the nursery and field

    Science.gov (United States)

    Qiaoyu Sun; R. Kasten Dumroese; Yong Liu

    2018-01-01

    Container volume and irrigation management affect seedling growth in the nursery and field. We evaluated the effects of container volumes (D40, 656 ml; D60, 983 ml) and subirrigation schedules (85%, 75%, 65%, and 55% of 100% total substrate moisture content, TSMC) on seedling growth in a greenhouse and outplanting performance of Chinese cork oak (Quercus variabilis...

  18. Tree-ring growth and wood chemistry response to manipulated precipitation variation for two temperate Quercus species

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Rebekah J. [Pennsylvania State University, University Park, PA; Kaye, Margot W. [Pennsylvania State University, University Park, PA; Abrams, Marc D. [Pennsylvania State University, University Park, PA; Hanson, Paul J [ORNL; Martin, Madhavi Z [ORNL

    2012-01-01

    We examined the relationship among ambient and manipulated precipitation, wood chemistry, and their relationship with radial growth for two oak species in eastern Tennessee. The study took place on the Walker Branch Throughfall Displacement Experiment (TDE) site, located at the Oak Ridge National Laboratory in Oak Ridge, TN. Two dominant species, white oak (Quercus alba) and chestnut oak (Quercus prinus), were selected for study from a 13-year experiment of whole-stand precipitation manipulation (wet, ambient and dry). The relationships between tree-ring width and climate were compared for both species to determine the impact of precipitation manipulations on ring width index. This study used experimental spectroscopy techniques to measure the sensitivity of tree-ring responses to directional changes in precipitation over 13 years, and the results suggest that oaks at this study site are resilient to imposed changes, but sensitive to inter-annual variations in climate. Laser-induced breakdown spectroscopy (LIBS) allowed us to measure nutrient intensities (similar to element concentrations) at 0.5-1.0 mm spacing along the radial growth axis of trees growing in the wet, ambient, and dry treatment sites. A difference in stemwood nutrient levels was observed between the two oak species and among the three treatments. Significant variation in element intensity was observed across treatments for some elements (Ca, K, Mg, Na, N and P) suggesting the potential for long-term impacts on growth under a changing climate regimes for southeastern oaks.

  19. Effects of leaf area of downy oak (Quercus pubescens Willd ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-18

    Aug 18, 2009 ... On the other hand, the light energy that is held by a leaf depends on the size of the leaf area (leaf surface). The measure of the leaf surface area (l.a.) is total leaf surface area of the plant (m2). The ratio between the total surface leaf area of a plant and the land area it covers (m2/ha or m2/m2) at a certain ...

  20. Genetic variation among Iranian oaks (Quercus spp.) using random ...

    African Journals Online (AJOL)

    ajl10

    2012-06-05

    04. 5´-AATCGGGCTG-3´. 60. Table 2. Primary analysis of PCR amplification products using selected primers. Primer. Number of bands Number of polymorphic bands Polymorphism (%) Molecular weight range (bp). OPB-01. 9.

  1. Responses of evergreen and deciduous Quercus species to enhanced ozone levels

    International Nuclear Information System (INIS)

    Calatayud, Vicent; Cervero, Julia; Calvo, Esperanza; Garcia-Breijo, Francisco-Jose; Reig-Arminana, Jose; Sanz, Maria Jose

    2011-01-01

    Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD 1.6 ) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. - Ozone tolerance overlapped with leaf traits in four Quercus species.

  2. Responses of evergreen and deciduous Quercus species to enhanced ozone levels

    Energy Technology Data Exchange (ETDEWEB)

    Calatayud, Vicent, E-mail: calatayud_viclor@gva.e [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Cervero, Julia; Calvo, Esperanza [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Garcia-Breijo, Francisco-Jose [Laboratorio de Anatomia e Histologia Vegetal ' Julio Iranzo' , Jardin Botanico, Universitat de Valencia, c/Quart 80, 46008 Valencia (Spain); Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Reig-Arminana, Jose [Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Sanz, Maria Jose [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain)

    2011-01-15

    Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD{sub 1.6}) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. - Ozone tolerance overlapped with leaf traits in four Quercus species.

  3. Oak regeneration and overstory density in the Missouri Ozarks

    Science.gov (United States)

    David R. Larsen; Monte A. Metzger

    1997-01-01

    Reducing overstory density is a commonly recommended method of increasing the regeneration potential of oak (Quercus) forests. However, recommendations seldom specify the probable increase in density or the size of reproduction associated with a given residual overstory density. This paper presents logistic regression models that describe this...

  4. Early results of planting English oak in an Ozark clearcut.

    Science.gov (United States)

    Paul S. Johnson

    1981-01-01

    Shoot growth and survival of container-grown and 1-0 bare-root English oak (Quercus robur L.) seedlings are reported for a 3-year period after planting in a clearcut. Effects of mulching with black polyethylene are also reported.

  5. Detection of defects in red oak deckboards by ultrasonic scanning

    Science.gov (United States)

    Mohammed F. Kabir; Daniel L. Schmoldt; Mark E. Schafer

    2000-01-01

    Experiments were conducted to detect defects in red oak (Quercus rubra, L.) deckboards by ultrasonic scanning. Scanning of the deckboards was carried out with two rolling transducers in a pitch-catch arrangement with pallet parts moving between the transducers at 70 ft/m and 220 ft/m. Data were collected, stored and processed using LabViewTM software. The defects...

  6. Coarse woody debris in oak woodlands of California.

    Science.gov (United States)

    William D. Tietje; Karen L. Waddell; Justin K. Vreeland; Charles L. Bolsinger

    2002-01-01

    An extensive forest inventory was conducted to estimate the amount and distribution of coarse woody debris (CWD) on 5.6 million ac of woodlands in California that are outside of national forests and reserved areas. Woodlands consist primarily of oak (Quercus spp.) types and are defined as forestland incapable of producing commercial quantities of...

  7. Distributional record of oak gall wasp (Hymenoptera: Cynipidae ...

    African Journals Online (AJOL)

    m

    2011-11-16

    Nov 16, 2011 ... Key words: Diversity, Similarity index, oak, gall wasps, forest. INTRODUCTION. The Zagros Mountains in Iran are divided into the northern Zagros and southern Zagros. West-Azerbaijan province is located in the northern Zagros that is the main habitat of Quercus infectoria Oliv (Fatahi, 1994; Sabeti,. 1998 ...

  8. Shelterwood-planted northern red oaks: integrated costs and options

    Science.gov (United States)

    Martin A. Spetich; Daniel Dey; Paul. Johnson

    2009-01-01

    Tree biology, environmental site conditions, relative monetary costs, management options, and the competitive struggle between planted trees and other vegetation were integrated when underplanting northern red oak (Quercus rubra L.) seedlings in Boston Mountain shelterwoods. This approach provides insight into the collective costs (...

  9. A mono harvest of California black oak acorns

    Science.gov (United States)

    Jonathan W. Long; Ron W. Goode

    2017-01-01

    In about 1925 or 1926, Margaret Baty, a tribal member of Big Sandy Rancheria, displayed a collection of acorns from California black oak (Quercus kelloggii, wi-yap' in Mono) and an acorn cooking basket. This photograph, taken by George Holt and courtesy of the Flegal Collection of the Jesse Peter Museum at Santa Rosa Junior College,...

  10. Photosynthate distribution patterns in cherrybark oak seedling sprouts

    Science.gov (United States)

    Brian Roy Lockhart; John D. Hodges; Emile S. Gardiner; Andrew W. Ezell

    2003-01-01

    Summary We used 14C tracers to determine photosynthate distribution in cherrybark oak (Quercus pagoda Raf.) seedling sprouts following release from competing mid-story vegetation. Fall acquisition of labeled photosynthates by seedlings followed expected source--sink patterns, with root and basal stem tissues...

  11. Leaf gas exchange of mature bottomland oak trees

    Science.gov (United States)

    Rico M. Gazal; Mark E. Kubiske; Kristina F. Connor

    2009-01-01

    We determined how changes in environmental moisture affected leaf gas exchange in Nuttall (Quercus texana Buckley), overcup (Q. lyrata Walt.), and dominant and codominant swamp chestnut (Q. michauxii Nutt.) oak trees in Mississippi and Louisiana. We used canopy access towers to measure leaf level gas...

  12. Taxonomic and functional diversity of a Quercus pyrenaicaWilld. Rhizospheric microbiome in the Mediterranean mountains

    OpenAIRE

    Cobo-Díaz, JF; Fernández-González, AJ; Villadas, PJ; Toro, N; Tringe, SG; Fernández-López, M

    2017-01-01

    © 2017 by the authors. Altitude significantly affects vegetation growth and distribution, including the developmental stages of a forest. We used shotgun Illumina sequencing to analyze microbial community composition and functional potential in melojo-oak (Quercus pyrenaica Willd.) rhizospheric soil for three different development stages along an altitudinal gradient: (a) a low altitude, non-optimal site for forest maintenance; (b) an intermediate altitude, optimal site for a forest; and (c) ...

  13. Effect of fungal infection on leaf gas-exchange and chlorophyll fluorescence in Quercus ilex

    OpenAIRE

    El Omari, Bouchra; Fleck, Isabel; Aranda, Xavier; Moret, Asumpció; MartíNadal,

    2001-01-01

    International audience; Experiments were conducted to study the susceptibility to infection by two fungal pathogens, Cryphonectria parasitica or Phomopsis spp. of undisturbed holm oaks (Quercus ilex) and the resprout from the stump of trees after excision of the shoot. Leaf gas-exchange and chlorophyll a fluorescence were recorded on plants growing in natural conditions for two years, as markers of disease progress at the first stages of infection. In infected plants, pathogen-induced stomata...

  14. Monitoring Genetic Stability in Quercus serrata Thunb. Somatic Embryogenesis Using RAPD Markers

    OpenAIRE

    Ramesh C., Thakur; Susumu, Goto; Katsuaki, Ishii; S. Mohan, Jain; Forestry and Forest Products Research Institute; Fukuoka Prefecture Forest Research and Extension Center; Forestry and Forest Products Research Institute; University of Helsinki

    1999-01-01

    Genetic stability of propagules regenerated via somatic embryogenesis is of paramount importance for its application to clonal forestry. Random amplified polymorphic DNA (RAPD) markers were used to determine the genetic stability in somatic embryogenesis of Quercus serrata Thunb. (Japanese white oak). Forty samples from an embryogenic line, consisting of regenerated plantlets, somatic embryos, and embryogenic calli, were examined using 54 decanucleotide primers. A total of 6520 clear reproduc...

  15. A cortiça como sonda ambiental de metais pesados: um serviço sócio-ambiental prestado por montados de sobro e sobreirais The cork as environmental probe of heavy metals: a socio- environmental service done by “montados” with cork oaks and cork oak stands (Quercus suber L.

    Directory of Open Access Journals (Sweden)

    J. Ponte-e-Sousa

    2007-01-01

    causa em cada camada da cortiça de sobreiros dispersos na área onde vegetam, poder obter-se uma estimativa dos teores médios desses metais nos locais frequentemente caracterizados pela presença daquela árvore, poderá vir a ser muito interessante para um conhecimento mais profundo desta realidade.The long term life of cork oak and the capacity that “amadia” cork has to build annual layers (highly separable allowed to create the hypothesis of correlation between the chemical marks made in each growing layer and the environmental characteristics of the place where the cork oak grows. This would allow to build space and time distribution series every nine years, about the characteristic in study. This is somewhat alike some dendrometric procedures, but these ones are much more aggressive. The objective of this work was to study lead (II in cork by voltammetry, because this method is well recognized as having competitive vantages over other known methods already used. The methodology adopted was: bark extraction, acid-hot digestion in closed recipient and voltammetric analytical signal search. The main conclusion is the possible association of this technique as another socioenvironmental service that “montado” can provide, in order to evaluate the quality of mediterranean basin continental areas with cork oak tree, regarding lead contamination.

  16. Occurrence of Phytophthora plurivora and other Phytophthora species in oak forests of southern Poland and their association with site conditions and the health status of trees

    Czech Academy of Sciences Publication Activity Database

    Jankowiak, R.; Stepniewska, H.; Bilanski,, P.; Kolařík, Miroslav

    2014-01-01

    Roč. 59, č. 6 (2014), s. 531-542 ISSN 0015-5632 Institutional support: RVO:61388971 Keywords : DECLINING OAK * QUERCUS-ROBUR * ROOT-ROT Subject RIV: EE - Microbiology, Virology Impact factor: 1.000, year: 2014

  17. Impact of straw and rock-fragment mulches on soil moisture and early growth of holm oaks in a semiarid area

    Science.gov (United States)

    M. N. Jimenez; J. R. Pinto; M. A. Ripoll; A. Sanchez-Miranda; F. B. Navarro

    2017-01-01

    Planted seedlings and saplings usually exhibit low survival and growth rates under dry Mediterranean environments, especially late-successional species such as Quercus. In this work, we studied the effects of straw and rock fragment mulches on the establishment conditions of holm oak (Quercus ilex L. subsp. ballota (Def.) Samp.) in SE Spain. Soil moisture was...

  18. Contrasting the effects of organic matter removal and soil compaction on root biomass of 9-year-old red oak, white oak, and shortleaf pine in a Missouri Ozark forest

    Science.gov (United States)

    Felix Jr. Ponder

    2011-01-01

    Nine-year old artificially regenerated red oak (Quercus rubra L.), white oak (Q. alba L.), and shortleaf pine (Pinus echinata Mill.) trees were excavated from plot borders of a U.S. Forest Service long-term soil productivity study in the Carr Creek State Forest near Ellington, MO, to quantify treatment effects on...

  19. Antioxidant Characterization of Oak Extracts Combining Spectrophotometric Assays and Chemometrics

    Directory of Open Access Journals (Sweden)

    Boris M. Popović

    2013-01-01

    Full Text Available Antioxidant characteristics of leaves, twigs, and acorns from two Serbian oak species Quercus robur L. and Quercus petraea L. from Vojvodina province (northern Serbia were investigated. 80% ethanol (in water extracts were used for antiradical power (ARP determinations against DPPH•, NO•, and O2∙- radicals, ferric reducing antioxidant power (FRAP, total phenol, tannin, flavonoid, and proanthocyanidin contents. Permanganate reducing antioxidant capacity (PRAC was determined using water extracts. Beside, mentioned parameters, soluble proteins, lipid peroxidation (LP, pigments and proline contents were also determined. The data of different procedures were compared and analyzed by multivariate techniques (correlation matrix calculation and principal component analysis (PCA. PCA found that investigated organs of two different oak tree species possess similar antioxidant characteristics. The superior antioxidant characteristics showed oak leaves over twigs and acorns and seem to be promising source of antioxidants with possible use in industry and pharmacy.

  20. First-Year Effects of Plastic Tube Shelters, Wire Cages, and Fertilization on Planted Nuttall Oak Seedlings

    Science.gov (United States)

    Troy S. Taylor; Michael S. Golden

    2002-01-01

    A Study was implemented in western Alabama to compare the growth and survival of Nuttall oak (Quercus nuttallii) seedlings using plastic tube shelters, wire browse protection, fertilization, and control. A total of 324 Nuttall oaks were planted at a bottomland site in Greene County, Alabama. One-third of the seedlings were enclosed in 46inch...

  1. A multiscale landscape approach to predicting bird and moth rarity hotspots in a threatened pitch pine-scrub oak community

    Science.gov (United States)

    Joanna Grand; John Buonaccorsi; Samuel A. Cushman; Curtice R. Griffin; Maile C. Neel

    2004-01-01

    In the northeastern United States, pitch pine (Pinus rigida Mill.)-scrub oak (Quercus ilicifolia Wang.) communities are increasingly threatened by development and fire suppression, and prioritization of these habitats for conservation is of critical importance. As a basis for local conservation planning in a pitch pine-scrub oak community in southeastern Massachusetts...

  2. Comparing single-tree selection, group selection, and clearcutting for regenerating oaks and pines in the Missouri Ozarks

    Science.gov (United States)

    Randy G. Jensen; John M. Kabrick

    2008-01-01

    In the Missouri Ozarks, there is considerable concern about the effectiveness of the uneven-aged methods of single-tree selection and group selection for oak (Quercus L.) and shortleaf pine (Pinus echinata Mill.) regeneration. We compared the changes in reproduction density of oaks and pine following harvesting by single-tree...

  3. Onderzoek naar de relatie tussen het zoutgehalte van de bodem, de bodemvruchtbaarheid, de vegetatie, de bladsamenstelling en de boniteit van opstanden van zomereik (Quercus robur) in de boswachterij Wieringermeer (voorjaar-najaar 1981) = Investigation of relationships between soil salinity, soil fertility, natural vegetation, foliar composition and site index of stands of pedunculate oak (Q.robur)

    NARCIS (Netherlands)

    Burg, van den J.; Leys, H.N.; Lynden, van K.R.

    1984-01-01

    Het verband tussen de natuurlijke vegetatie, het bodemprofiel, de bodemchemische eigenschappen, de grondwaterstand, het zoutgehalte van de bodem en de boniteit van zomereik (Quercus robur) werd in 1981 onderzocht in 26 proefplekken in de boswachterij Wieringermeer. Het doel van het onderzoek in deze

  4. Comparison between the contribution of ellagitannins of new oak barrels and one-year-used barrels

    Directory of Open Access Journals (Sweden)

    Navarro María

    2016-01-01

    Full Text Available The influence of the botanical origin (French oak: Quercus petraea and American oak: Quercus alba, toasting level and if the barrel were new of previously used during one year have been studied. Results indicate that French oak released significant higher amounts of ellagitannins than American oak. Toasting level also exert a great influence. The higher the toasting level the lower the ellagitannin concentration in wines. Finally, the use during one year of the barrels drastically decreases the ellagitannin concentration in wines. Consequently, it can be concluded that the origin of oak, the toasting level and especially the previous use of the barrels have a very significant influence on the final ellagitannin concentration in wine, and probably on its sensory impact.

  5. TESTING BAYESIAN ALGORITHMS TO DETECT GENETIC STRUCTURE IN TWO CLOSELY RELATED OAK TAXA

    Directory of Open Access Journals (Sweden)

    Cristian Mihai Enescu

    2013-12-01

    Full Text Available The aim of this study was to test the Bayesian algorithm implemented in the software STRUCTURE in order to detect the number of clusters, by using microsatellite data from four oak species. Several assignment models, with or without a priori grouping of individuals to species, were proposed. Better results were obtained by using the sampling location information and when only two taxa were analyzed. Particularly, pedunculate oak and sessile oak formed distinct clusters whatever the assignment model we use. By contrast, no separation between the two oaks from series Lanuginosae was observed. This can be explained, on one hand, by the small sampling size for Italian oak, or by the genetic similarities of the two pubescent oaks, namely Quercus pubescens and Q. virgiliana, on the other hand. Our findings support the hypothesis according which Italian oak is an intraspecific taxonomic unit of pubescent oak.

  6. A neighborhood analysis of the consequences of Quercus suber decline for regeneration dynamics in Mediterranean forests.

    Directory of Open Access Journals (Sweden)

    Beatriz Ibáñez

    Full Text Available In forests, the vulnerable seedling stage is largely influenced by the canopy, which modifies the surrounding environment. Consequently, any alteration in the characteristics of the canopy, such as those promoted by forest dieback, might impact regeneration dynamics. Our work analyzes the interaction between canopy neighbors and seedlings in Mediterranean forests affected by the decline of their dominant species (Quercus suber. Our objective was to understand how the impacts of neighbor trees and shrubs on recruitment could affect future dynamics of these declining forests. Seeds of the three dominant tree species (Quercus suber, Olea europaea and Quercus canariensis were sown in six sites during two consecutive years. Using a spatially-explicit, neighborhood approach we developed models that explained the observed spatial variation in seedling emergence, survival, growth and photochemical efficiency as a function of the size, identity, health, abundance and distribution of adult trees and shrubs in the neighborhood. We found strong neighborhood effects for all the performance estimators, particularly seedling emergence and survival. Tree neighbors positively affected emergence, independently of species identity or health. Alternatively, seedling survival was much lower in neighborhoods dominated by defoliated and dead Q. suber trees than in neighborhoods dominated by healthy trees. For the two oak species, these negative effects were consistent over the three years of the experimental seedlings. These results indicate that ongoing changes in species' relative abundance and canopy trees' health might alter the successional trajectories of Mediterranean oak-forests through neighbor-specific impacts on seedlings. The recruitment failure of dominant late-successional oaks in the gaps opened after Q. suber death would indirectly favor the establishment of other coexisting woody species, such as drought-tolerant shrubs. This could lead current

  7. ( Quercus spp. ) using random amplified polymorphic DNA (RAPD)

    African Journals Online (AJOL)

    Quercus is one of the most important woody genera of the Northern hemisphere and considered as one of the main forest tree species in Iran. In this study, genetic relationships in the genus Quercus, using random amplified polymorphic DNA (RAPD) was examined. Five species, including: Quercus robur, Quercus ...

  8. Penicillium cecidicola, a new species on cynipid insect galls on Quercus pacifica in the western United States

    DEFF Research Database (Denmark)

    Seifert, K.A.; Hoekstra, E.H.; Frisvad, Jens Christian

    2004-01-01

    A synnematous species of Penicillium subgenus Biverticillium was found inside emergence tunnels from insect galls (Cynipidae, Hymenoptera, the so-called gall wasps) on scrub oaks (Quercus pacifica Nixon & C.H. Muller) collected in the western United States. The fungus produces synnemata with white...... isolates exposed to light after 10 days. The fungus produces the extrolite apiculide A and a series of unidentified extrolites also produced by P. panamense. The oak gall species is described here as Penicillium cecidicola and compared with similar species. An ITS phylogeny suggests that P. cecidicola...

  9. Thinning to improve growth, bole quality, and forest health in an Inonotus hispidus-infected, red oak-sweetgum stand in the Mississippi Delta: 10-year results

    Science.gov (United States)

    James S. Meadows; Theodor D. Leininger; David Montwé; T. Evan Nebeker

    2013-01-01

    A 55-year-old red oak-sweetgum (Quercus spp.- Liquidambar styraciflua) stand on the Delta National Forest in western Mississippi was subjected to a combination of low thinning and improvement cutting in 1997. Special emphasis was placed on removing all red oaks infected with Inonotus hispidus, a canker decay...

  10. Mass loss and nutrient concentrations of buried wood as a function of organic matter removal, soil compaction, and vegetation control in a regenerating oak-pine forest

    Science.gov (United States)

    Felix Ponder; John M. Kabrick; Mary Beth Adams; Deborah S. Page-Dumroese; Marty F. Jurgensen

    2017-01-01

    Mass loss and nutrient concentrations of northern red oak (Quercus rubra) and white oak (Q. alba) wood stakes were measured 30 months after their burial in the upper 10 cm of soil in a regenerating forest after harvesting and soil disturbance. Disturbance treatments were two levels of organic matter (OM) removal (only...

  11. Influence of planting stocks on the survival and growth of Nuttall and cherrybark oak planted on lands damaged by Hurricane Katrina

    Science.gov (United States)

    Derek K. Alkire; James C. Rainer; Andrew B. Self; Andrew W. Ezell; Andrew J. Londo; Emily B. Schultz

    2013-01-01

    Bare-root, container, and root production method (RPMTM) seedlings of Nuttall oak (Quercus texana Buckley) and cherrybark oak (Q. pagoda Ell.) were planted on lands damaged by Hurricane Katrina in southern Mississippi to compare the height growth, groundline diameter (GLD) growth, and survival of the...

  12. Host-induced genome alterations in Phytophthora ramorum, I. NA1 lineage on coast live oak in California, II. EU1 lineage on Chamaecyparis lawsoniana in UK

    Science.gov (United States)

    Takao Kasuga; Mai Bui; Elizabeth Bernhardt; Tedmund Swiecki; Kamyar Aram; Lien Bertier; Jennifer Yuzon; Liliana M. Cano; Joan Webber; Clive Brasier; Caroline Press; Niklaus Grünwald; David Rizzo; Matteo Garbelotto

    2017-01-01

    Rapid phenotypic diversification in clonal invasive populations is often observed, although the underlying genetic mechanisms remain elusive. Lineages of the sudden oak death pathogen Phytophthora ramorum are exclusively clonal, yet isolates of the NA1 lineage from oak (Quercus spp.) frequently exhibit...

  13. Changes in the Chemical Composition of Plum Distillate During Maturation with Oak Chips under Different Conditions

    Directory of Open Access Journals (Sweden)

    Maria Balcerek

    2017-01-01

    Full Text Available This study investigates the eff ect of ageing on the qualitative and quantitative composition of plum distillate in contact with oak wood chips. Maturation was performed with lightly toasted French oak (Quercus sessifl ora and Quercus robur chips or oak chips made from fragments of empty barrels that had been used for ageing cognac. The eff ects of oak chip dose, process temperature, ageing system (static or circulatory and ultrasound treatment were assessed. Maturation of plum distillate samples with oak chips resulted in higher levels of extractable organics (including tannins and colour changes, which were correlated with the type and dose of oak chips, and the conditions of maturation. The content of sugars such as glucose, xylose and arabinose also increased, depending on the conditions and type of oak chips. Degradation of lignin resulted in liberation of sinapaldehyde, syringaldehyde, coniferaldehyde and vanillin, with intensities depending on the applied parameters. In terms of volatiles, decreases in the concentration of higher alcohols and aliphatic aldehydes were observed in the majority of maturation experiments, while concentrations of furanic aldehydes increased depending on the type and dose of oak chips, as well as on the conditions of maturation. The quantities of esters such as ethyl acetate decreased in the majority of experimental variants, whereas concentrations of ethyl caproate, ethyl caprylate and ethyl caprate increased gradually. Some phenols and lactones were detected in all matured samples, with the lowest levels found in the samples aged with oak chips made from cognac barrels.

  14. Changes in the Chemical Composition of Plum Distillate During Maturation with Oak Chips under Different Conditions.

    Science.gov (United States)

    Balcerek, Maria; Pielech-Przybylska, Katarzyna; Dziekońska-Kubczak, Urszula; Patelski, Piotr; Strąk, Ewelina

    2017-09-01

    This study investigates the effect of ageing on the qualitative and quantitative composition of plum distillate in contact with oak wood chips. Maturation was performed with lightly toasted French oak ( Quercus sessiflora and Quercus robur ) chips or oak chips made from fragments of empty barrels that had been used for ageing cognac. The effects of oak chip dose, process temperature, ageing system (static or circulatory) and ultrasound treatment were assessed. Maturation of plum distillate samples with oak chips resulted in higher levels of extractable organics (including tannins) and colour changes, which were correlated with the type and dose of oak chips, and the conditions of maturation. The content of sugars such as glucose, xylose and arabinose also increased, depending on the conditions and type of oak chips. Degradation of lignin resulted in liberation of sinapaldehyde, syringaldehyde, coniferaldehyde and vanillin, with intensities depending on the applied parameters. In terms of volatiles, decreases in the concentration of higher alcohols and aliphatic aldehydes were observed in the majority of maturation experiments, while concentrations of furanic aldehydes increased depending on the type and dose of oak chips, as well as on the conditions of maturation. The quantities of esters such as ethyl acetate decreased in the majority of experimental variants, whereas concentrations of ethyl caproate, ethyl caprylate and ethyl caprate increased gradually. Some phenols and lactones were detected in all matured samples, with the lowest levels found in the samples aged with oak chips made from cognac barrels.

  15. Growth Versus Storage in Quercus Leucotrichophora And Pinus Roxburghii Seedlings in Responses to Changes In Nutrient and Water Availability

    OpenAIRE

    Kiran Bargali; S. S. Bargali

    2015-01-01

    In this paper, growth and storage of carbon and nitrogen in seedlings of banj oak (Quercus leucotrichophora A. Camus) and chir pine (Pinus roxburghii Sarg.) have been compared across different levels of nutrient and water availabilities. Four nutrient (144, 264, 384 and 504 mg of NPK fertilizer per kg soil) and three watering (21 days, 14 days and 7 days interval) treatments were applied to seedlings. At low watering levels, seedling dry mass of both the species decreased towards higher nutri...

  16. Pathogenicity of Armillaria Isolates Inoculated on Five Quercus Species at Different Watering Regimes

    Directory of Open Access Journals (Sweden)

    R. Metaliaj

    2006-04-01

    Full Text Available One of three fungal isolates of Armillaria mellea (Vahl: Fr. P. Kummer, A. gallica Marxm. et Romagn. and A. tabescens (Scop.: Fr. Emel. was inoculated on 1,440 three-year-old potted seedlings of five Quercus species (Q. cerris L., Q. ilex L., Q. pubescens Willd., Q. robur L. and Q. trojana Webb. grown at different watering regimes in a greenhouse. Inoculum was represented by a piece of an oak branch colonised with the fungus (or sterile, as a control, which was attached to the unwounded main root of each oak seedling. During the growing season, differences in water availability among seedlings were measured monthly using minimum water potential assessments on noninoculated seedlings receiving an equal amount of water. Although all three Armillaria isolates induced infection, the A. mellea isolate was most pathogenic in all cases, while the A. gallica isolate showed a statistically equal degree of pathogenicity only on the least watered seedlings. Of the Quercus species, Q. ilex showed the greatest number of infected seedlings, Q. robur the smallest. Reducing the water supply to potted oak seedlings could be a useful indicator for detecting differences in pathogenicity between Armillaria species.

  17. Oak Decline

    Science.gov (United States)

    Vernon Ammon; T. Evan Nebeker; Ted H. Filer; Francis I. McCracken; J. D. Solomon; H. E. Kennedy

    1989-01-01

    Occurrence of decline and mortality in this nation's hardwood forests has been documented in reports for the past 130 years. From 1856 through 1981, more than 26 decline events were reported from eight eastern states affecting almost all species of oaks. Fourteen factors have been implicated as either primary or secondary agents responsible for decline and...

  18. The importance of crown cover on the sustainability of cork oak stands

    OpenAIRE

    Ribeiro, Nuno de Almeida; Surovy, Peter; Gonçalves, Ana Cristina; Gonçalves Ferreira, Alfredo

    2004-01-01

    The cork oak (Quercus suber L.) production system in Portugal, referred to as montado, occupies 713,000 ha representing 22% of Portugal’s forest area. In the last 5 decades several changes occurred in the forest management of cork oak stands, mainly due to the reduction of hand labour and increasing mechanization, creating a new set of risk factors to production system sustainability. Of all risk factors, soil loss, crown cover reduction and lack of regeneration are responsible for the degrad...

  19. Comparison of water-use efficiency of seedlings from two sympatric oak species: genotype × environment interactions

    OpenAIRE

    Ponton, Stéphane; Dupouey, Jean-Luc; Breda, Nathalie; Dreyer, Erwin

    2002-01-01

    Seedlings of two sympatric oak species, Quercus robur L. and Quercus petraea (Matt.) Liebl., were grown in common garden conditions to test for potential interspecific differences in intrinsic water-use efficiency (WUE). Intrinsic water-use efficiency was estimated based on carbon isotope composition of shoots (δ13C) and on gas exchange measurements (ratio of net CO2 assimilation rate to stomatal conductance (A/gsw)). In addition, genotype × environment interactions were tested by sub...

  20. Stimulation of Armillaria rhizomorph growth by oak root fungi

    Directory of Open Access Journals (Sweden)

    Hanna Kwaśna

    2014-08-01

    Full Text Available Thirty one different genera of fungi were isolated from the wood of roots of 5O·year·old oak (Quercus robur. The most frequently isolated fungi were: Mycelium radicis atrovirens alpha (MRAA, Clonostachys sp. and Penicillium daleae, Beauveria bassiana, Clonostachys sp., Cryplosporiopsis rodicicolo, Geotrichum candidum, Mortierella vinacea, MRAA, P. daleae, P. janczewskii P. spinulosum, Sporothrix schenckii and Tolypocladium niveum significantly enhanced Armillaria mellea rhizomorph initiation and growth from oak branch segments in vitro. The biggest stimulation effect was noticed when the dematiaceous hyphomycetes, e.g. MRAA, P. dimorphospora and S. schenckii were studied.

  1. Approaches to restoration of oak forests on farmed lowlands of the Mississippi River and its tributaries

    Science.gov (United States)

    Emile S. Gardiner; Daniel C. Dey; John A. Stanturf; Brian Roy. Lockhart

    2010-01-01

    The lowlands associated with the Mississippi River and its tributaries historically supported extensive broadleaf forests that were particularly rich in oak (Quercus spp.) species. Beginning in the 1700s, deforestation for agriculture substantially reduced the extent of the original forest, and fragmented the remainder into small parcels. More...

  2. Oak mast production and animal impacts on acorn survival in the central hardwoods

    Science.gov (United States)

    Kenneth F. Kellner; Jeffery K. Riegel; Nathanael I. Lichti; Robert K. Swihart

    2013-01-01

    As part of the Hardwood Ecosystem Experiment we measured mast production in white (Quercus alba) and black (Q. velutina) oak, and quantified the impacts of seed predators on acorn survival over a 3-year period. Specifically, we measured the proportion of acorns of each species infested with weevils (Curculio spp...

  3. Product recovery from tree grade 1 northern red oak on Menominee tribal lands

    Science.gov (United States)

    John P. Dwyer; Daniel C. Dey

    2007-01-01

    Since 1854 the Menominee Tribal people have practiced some level of forest management on their lands. In April of 2000, Menominee Tribal Enterprises (MTE) forestry staff along with federal, state, and university researchers began a comprehensive study of value in northern red oak (Quercus rubra L.). One of the objectives of this study was to relate...

  4. Root morphology and growth of bare-root seedlings of Oregon white oak

    Science.gov (United States)

    Peter J. Gould; Constance A. Harrington

    2009-01-01

    Root morphology and stem size were evaluated as predictors of height and basal-area growth (measured at groundline) of 1-1 Oregon white oak (Quercus garryana Dougl. ex Hook.) seedlings planted in raised beds with or without an additional irrigation treatment. Seedlings were classified into three root classes based on a visual assessment of the...

  5. The Effect of Low Oxygen Stress on Phytophthora cinnamomi Infection and Disease of Cork Oak Roots

    Science.gov (United States)

    Karel A. Jacobs; James D. MacDonald; Alison M. Berry; Laurence R. Costello

    1997-01-01

    The incidence and severity of Phytophthora cinnamomi Rands root disease was quantified in cork oak (Quercus suber L.) roots subjected to low oxygen (hypoxia) stress. Seedling root tips were inoculated with mycelial plugs of the fungus and incubated in ≤1, 3-4, or 21 percent oxygen for 5 days. Ninety-four percent of roots...

  6. White oak epicotyl emergence and 1-0 seedling growth from surgically altered germinating acorns

    Science.gov (United States)

    Shi-Jean Susana Sung; Paul P. Kormanik; Stanley J. Zarnoch

    2010-01-01

    Open-pollinated white oak (Quercus alba L.) acorns were collected and stored at 4 °C in November 2004. Three days before sowing in early December, we treated germinating acorns in five ways: no surgery (C); one half of the radical cut off (HR); whole radicle cut off (WR); one cotyledonary petiole severed (OP); and both cotyledonary petioles severed,...

  7. The Vallarta Botanical Garden's advancements in conserving the diversity of native Mexican oaks and magnolias

    Science.gov (United States)

    N.A. Gerlowski; M.A. Muñiz-Castro

    2017-01-01

    Mexico is both an oak (Quercus) biodiversity hotspot (over 160 described species) and the western hemisphere's leader in magnolia (Magnolia) diversity (36 described species). In the face of myriad threats to these groups, including climate change, habitat loss/fragmentation, overharvesting, and plant pests/pathogens, the...

  8. Prediction of growth and mortality of Oregon White Oak in the Pacific Northwest.

    Science.gov (United States)

    Peter J. Gould; David D. Marshall; Constance A. Harrington

    2008-01-01

    We developed new equations to predict Oregon white oak (Quercus garryana Dougl. ex Hook.) development with ORGANON, a stand-development model that is widely used in the Pacific Northwest. Tree size, competitive status, crown ratio, and site productivity were statistically significant predictors of growth and mortality. Three scenarios were...

  9. Long-term above-ground biomass production in a red oak-pecan agroforestry system

    Science.gov (United States)

    Agroforestry systems have widely been recognized for their potential to foster long-term carbon sequestration in woody perennials. This study aims to determine the above-ground biomass in a 16-year-old red oak (Quercus rubra) - pecan (Carya illinoinensis) silvopastoral planting (141 and 53 trees ha-...

  10. Predicting root biomass of burned and unburned white oak advance reproduction from diameter and height

    Science.gov (United States)

    Benjamin O. Knapp; G. Geoff Wang; David H. Van Lear; Joan L. Walker

    2006-01-01

    The size, especially the root size, of advance oak (Quercus spp.) reproduction provides the best indication of the growth potential after release or top-kill. This study examined the relationship between the size of the root system and various diameter height measurements for small (

  11. Prescribed Fire Impacts to Amphibians and Reptiles in Shelterwood-harvested Oak-dominated Forests

    Science.gov (United States)

    Patrick D. Keyser; David J. Sausville; W. Mark Ford; Donald J. Schwab; Partick H. Brose

    2004-01-01

    As part of a larger study examining the role of prescribed fire in regenerating upland oaks (Quercus spp.), seasonal prescribed burns (winter, spring, summer, and unburned control) were applied to first-stage shelterwood-harvested stands on Horsepen Wildlife Management Area in the Virginia Piedmont in 1995. Because fire impacts are poorly documented...

  12. Clitocybe tabescens associated with decline and death of Chinese elm and water oak

    Science.gov (United States)

    T. H. Filer; F. I. McCracken

    1969-01-01

    In 1964, decline symptoms were found on 48 Chinese elms (Ulmus parvifolia) and 2 water oaks (Quercus nigra) in Washington County, Mississippi. Some of their foliage was yellowish, and small lateral branches were dying in parts of the crowns. Large branches later died and the entire crowns were infected.

  13. Differentiating defects in red oak lumber by discriminant analysis using color, shape, and density

    Science.gov (United States)

    B. H. Bond; D. Earl Kline; Philip A. Araman

    2002-01-01

    Defect color, shape, and density measures aid in the differentiation of knots, bark pockets, stain/mineral streak, and clearwood in red oak, (Quercus rubra). Various color, shape, and density measures were extracted for defects present in color and X-ray images captured using a color line scan camera and an X-ray line scan detector. Analysis of variance was used to...

  14. Seasonal trends in response to inoculation of coast live oak with Phytophthora ramorum

    Science.gov (United States)

    Richard S. Dodd; Daniel Hüberli; Tamar Y. Harnik; Brenda O' Dell; Matteo Garbelotto

    2006-01-01

    We developed a branch cutting inoculation method to provide a controlled system for studying variation in response to inoculation of coast live oak (Quercus agrifolia) with Phytophthora ramorum. This method has advantages over inoculations of trees in the field, in containing the inoculum and in allowing high levels of replication...

  15. Ethanol attracts scolytid beetles to Phytophthora ramorum cankers on coast live oak [Abstract

    Science.gov (United States)

    Rick G. Kelsey; Maia Beh; Dave Shaw; Daniel K. Manter

    2013-01-01

    Successful infection of coast live oak (Quercus agrifolia Née) stems by Phytophthora ramorum results in the formation of a canker visible initially at the bark surface by the release of a dark red to black colored exudate referred to as "bleeding." Bark and ambrosia beetles are often attracted to diseased trees within...

  16. Elevated CO2 compensates for water stress in northern red oak

    Science.gov (United States)

    Patricia T. Tomlinson; Paul D. Anderson

    1996-01-01

    Global climate change models predict decreased rainfall in association with elevated CO2 in the western Lakes States region. Currently, the western edge of northern red oak (Quercus rubra L.) distribution coincides with the most xeric conditions of its ecological range. Decreased rainfall and water availability could alter...

  17. Spring temperature responses of oaks are synchronous with North Atlantic conditions during the last deglaciation

    Science.gov (United States)

    Steven L. Voelker; Paul-Emile Noirot-Cosson; Michael C. Stambaugh; Erin R. McMurry; Frederick C. Meinzer; Barbara Lachenburch; Richard P. Guyette

    2012-01-01

    Paleoclimate proxies based on the measurement of xylem cell anatomy have rarely been developed across the temperature range of a species or applied to wood predating the most recent millennium. Here we describe wood anatomy-based proxies for spring temperatures in central North America from modern bur oaks (Quercus macrocarpa Michx.). The strong...

  18. Seedling Establishment of Coast Live Oak in Relation to Seed Caching by Jays

    Science.gov (United States)

    Joe R. McBride; Ed Norberg; Sheauchi Cheng; Ahmad Mossadegh

    1991-01-01

    The purpose of this study was to simulate the caching of acorns by jays and rodents to see if less costly procedures could be developed for the establishment of coast live oak (Quercus agrifolia). Four treatments [(1) random - single acorn cache, (2) regular - single acorn cache, (3) regular - 5 acorn cache, (4) regular - 10 acorn cache] were planted...

  19. Response of upland oak and co-occurring competitor seedlings following single and repeated prescribed fires

    Science.gov (United States)

    Heather D. Alexander; Mary Arthur; David Loftis; Stephanie Green

    2009-01-01

    Studies within and outside the United States indicate recurring oak (Quercus spp.) regeneration problems. In deciduous forests of the eastern U.S., a prevailing explanation for this trend is that fire suppression leads to high competitor abundance and low understory light. In response, prescribed fire is increasingly used as a management tool to...

  20. California black oak response to nitrogen amendment at a high O3, nitrogen-saturated site

    Science.gov (United States)

    Nancy Grulke; W. Dobrowolski; P. Mingus; M.E. Fenn

    2005-01-01

    In a nitrogen (N) saturated forest downwind from Los Angeles, California, the cumulative response to long-term background-N and N-amendment on black oak (Quercus kelloggii) was described in a below-average and average precipitation year. Monthly measurements of leaf and branch growth, gas exchange, and canopy health attributes were conducted. The...

  1. Estimating mast production: an evaluation of visual surveys and comparison with seed traps using white oaks

    Science.gov (United States)

    Roger W. Perry; Ronald E. Thill

    1999-01-01

    Perry and Thill compared five types of visual mast surveyed with seed trap data from 105 white oaks (Quercus alba L.) during 1996-1997 in the Ouachita Mountains of Arkansas. They also evaluated these visual survey methods for their usefulness in detecting differences in acorn density among areas. Indices derived from all five methods were highly...

  2. The resilience of upland-oak forest canopy trees to chronic and acute precipitation manipulations

    Science.gov (United States)

    Paul J. Hanson; Timothy J. Tschaplinski; Stand D. Wullschleger; Donald e. Todd; Robert M. Auge

    2007-01-01

    Abstract—Implications of chronic (±33 percent) and acute (-100 percent) precipitation change were evaluated for trees of upland-oak forests of the eastern United States. Chronic manipulations have been conducted since 1993, and acute manipulations of dominant canopy trees (Quercus prinus; Liriodendron tulipifera) were initiated in 2003. Through 12...

  3. Oak, fire, and global change in the eastern USA: what might the future hold?

    Science.gov (United States)

    James M. Vose; Katherine Elliott

    2016-01-01

    The pace of environmental and socioeconomic change over the past 100 years has been rapid. Changes in fire regimes, climate, and land use have shaped the structure and function of most forest ecosystems, including oak (Quercus spp. L.) forests in the eastern United States.New stressors such as air pollution and invasive species have contributed to...

  4. Large Drought-Induced Variations in Oak Leaf Volatile Organic Compound Emissions during PINOT NOIR 2012

    Science.gov (United States)

    Leaf-level isoprene and monoterpene emissions were collected and analyzed from five of the most abundant oak (Quercus) species in Central Missouri’s Ozarks Region in 2012 during PINOT NOIR (Particle Investigations at a Northern Ozarks Tower ‐ NOx, Oxidants, Isoprene Research). Ju...

  5. Shading and root-shoot relations in saplings of silver birch, pedunculate oak and beech

    NARCIS (Netherlands)

    Hees, van A.F.M.; Clerkx, A.P.P.M.

    2003-01-01

    Silver birch (Betula pendula Roth), pedunculate oak (Quercus robur L.) and beech (Fagus sylvatica L.) can regenerate successfully under a canopy of Scots pine (Pinus sylvestris L.). Shading reduces plant growth and modifies plant form, two related aspects. This study focuses on the effects of

  6. High rates of gene flow by pollen and seed in oak populations across Europe

    NARCIS (Netherlands)

    Gerber, S.; Chadoeuf, J.; Gugerli, F.; Lascoux, M.; Buiteveld, J.; Cottrell, J.; Dounavi, A.; Fineschi, S.; Forrest, L.; Fogelqvist, J.; Goicoechea, P.G.; Jensen, J.S.; Salvini, D.; Vendramin, G.G.; Kremer, A.

    2014-01-01

    Gene flow is a key factor in the evolution of species, influencing effective population size, hybridisation and local adaptation. We analysed local gene flow in eight stands of white oak (mostly Quercus petraea and Q. robur, but also Q. pubescens and Q. faginea) distributed across Europe. Adult

  7. Fossil oak galls preserve ancient multitrophic interactions.

    Science.gov (United States)

    Stone, Graham N; van der Ham, Raymond W J M; Brewer, Jan G

    2008-10-07

    Trace fossils of insect feeding have contributed substantially to our understanding of the evolution of insect-plant interactions. The most complex phenotypes of herbivory are galls, whose diagnostic morphologies often allow the identification of the gall inducer. Although fossil insect-induced galls over 300Myr old are known, most are two-dimensional impressions lacking adequate morphological detail either for the precise identification of the causer or for detection of the communities of specialist parasitoids and inquilines inhabiting modern plant galls. Here, we describe the first evidence for such multitrophic associations in Pleistocene fossil galls from the Eemian interglacial (130000-115000 years ago) of The Netherlands. The exceptionally well-preserved fossils can be attributed to extant species of Andricus gallwasps (Hymenoptera: Cynipidae) galling oaks (Quercus), and provide the first fossil evidence of gall attack by herbivorous inquiline gallwasps. Furthermore, phylogenetic placement of one fossil in a lineage showing obligate host plant alternation implies the presence of a second oak species, Quercus cerris, currently unknown from Eemian fossils in northwestern Europe. This contrasts with the southern European native range of Q. cerris in the current interglacial and suggests that gallwasp invasions following human planting of Q. cerris in northern Europe may represent a return to preglacial distribution limits.

  8. Estudio cariológico de Quercus humboldtti Bonpl Caryological study of Quercus humboldtii Bonpl

    Directory of Open Access Journals (Sweden)

    Alvarado de Coral Cecilia

    1989-12-01

    Full Text Available Se comprobó que la especie del roble Ouercus humboldtii Bonpl. tiene 2 n= 24 cromosomas, al igual que la mayoría de las especies estudiadas de Quercus. Utilizando pretratamiento y tinción con orceina lactopropiónica fue posible obtener el cariotipo e ideograma.Using lactopropionic orceine for a previus tintion we obtained the Caryotype and ideogram of Quercus humboldtii Bonpl. and we observed that it has 2 n = 24 chromosomes as most studied species of Quercus do.

  9. Characterization of Quercus species distributed in Jordan using ...

    African Journals Online (AJOL)

    User

    2013-03-20

    Mar 20, 2013 ... improving conservation, restoration and reforestation strategies of Quercus in Jordan. Key words: Quercus spp., genetic ... ciation of the Mediterranean sclerophyllous broad-leaf forests (Schiller et al., 2004a). ..... genetic diversity and differentiation of Quercus crispula in the. Chichibu Mountains, central ...

  10. Mortality due to Japanese oak wilt disease and surrounding forest compositions

    Directory of Open Access Journals (Sweden)

    Michio Oguro

    2015-12-01

    Full Text Available Japanese oak wilt (Raffaelea quercivora is a vector-borne disease transmitted by the flying ambrosia beetle, Platypus quercivorus, and causes mass mortality in the fagaceous species of Japan. The data described in this article are available in Mendeley Data, DOI: 10.17632/xwj98nb39r.1 [1] and include the mortality status of 1089 Quercus crispula and 846 Quercus serrata trees and surrounding forest conditions. The findings using this dataset were published in M. Oguro, S. Imahiro, S. Saito, T. Nakashizuka, Relative importance of multiple scale factors to oak tree mortality due to Japanese oak wilt disease, For. Ecol. Manag. (2015 doi:10.1016/j.foreco.2015.07.016 [2].

  11. Large-scale patterns of Quercus ilex, Quercus suber, and Quercus pyrenaica regeneration in central-western Spain

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Rolo, Víctor; Moreno, Gerardo

    2010-01-01

    In Central-Western Spain, forests and woodlands composed of Quercus sp. support outstanding levels of biodiversity, but there is increasing concern about their long-term persistence due to a lack of regeneration. We hypothesize that this regenerative lack is operating on a large geographic scale...

  12. Adaptive and plastic responses of Quercus petraea populations to climate across Europe

    DEFF Research Database (Denmark)

    Sáenz-Romero, Cuauhtémoc; Lamy, Jean-Baptiste; Ducousso, Alexis

    2017-01-01

    How temperate forests will respond to climate change is uncertain; projections range from severe decline to increased growth. We conducted field tests of sessile oak (Quercus petraea), a widespread keystone European forest tree species, including more than 150 000 trees sourced from 116 geographi...... and negatively affected (Bercé, France), while populations at the contemporary northern limit (colder and humid maritime regions; Denmark and Norway) will probably not show large changes in growth and survival in response to climate change.......How temperate forests will respond to climate change is uncertain; projections range from severe decline to increased growth. We conducted field tests of sessile oak (Quercus petraea), a widespread keystone European forest tree species, including more than 150 000 trees sourced from 116...... of differential population responses to climate (genetic differentiation due to past divergent climatic selection vs. plastic responses to ongoing climate change) and (ii) to explore which climatic variables (temperature or precipitation) trigger the population responses. Tree growth and survival were modeled...

  13. Contrasting root associated fungi of three common oak-woodland plant species based on molecular identification: host specificity or non-specific amplification?

    Science.gov (United States)

    Douhan, Greg W; Petersen, Carolyn; Bledsoe, Caroline S; Rizzo, David M

    2005-07-01

    An increasingly popular approach used to identify arbuscular mycorrhizal (AM) fungi in planta is to amplify a portion of AM fungal small subunit ribosomal DNA (SSU-rDNA) from whole root DNA extractions using the primer pair AM1-NS31, followed by cloning and sequencing. We used this approach to study the AM fungal community composition of three common oak-woodland plant species: a grass (Cynosurus echinatus), blue oak (Quercus douglasii), and a forb (Torilis arvensis). Significant diversity of AM fungi were found in the roots of C. echinatus, which is consistent with previous studies demonstrating a high degree of AM fungal diversity from the roots of various hosts. In contrast, clones from Q. douglasii and T. arvensis were primarily from non-AM fungi of diverse origins within the Ascomycota and Basidiomycota. This work demonstrates that caution must be taken when using this molecular approach to determine in planta AM fungal diversity if non-sequence based methods such as terminal restriction fragment length polymorphisms, denaturing gradient gel electrophoresis, or temperature gradient gel electrophoresis are used.

  14. Molecular and Morphological Characterization of Xiphinema chambersi Population from Live Oak in Jekyll Island, Georgia, with Comments on Morphometric Variations

    OpenAIRE

    Handoo, Zafar A.; Carta, Lynn K.; Skantar, Andrea M.; Subbotin, Sergei A.; Fraedrich, Stephen W.

    2016-01-01

    A population of Xiphinema chambersi from the root zone around live oak (Quercus virginiana Mill.) trees on Jekyll Island, GA, is described using both morphological and molecular tools and compared with descriptions of type specimens. Initially, because of a few morphological differences, this nematode was thought to represent an undescribed species. However, on further examination, the morphometrics of the nematodes from live oak tend to agree with most of the morphometrics in the original de...

  15. Quercus petraea in België

    NARCIS (Netherlands)

    Rompaey, van E.

    1957-01-01

    Naar aanleiding van het artikel over Quercus petraea in het Corr. bl. no. 4 zend ik u hierbij een kopie van de Belgische verspreidingskaart, omdat daar m.i. wel een en ander uit af te leiden is, dat ook Nederland aanbelangt: 1. Bij bet massale verspreidingsgebied ten Z. van de lijn Samber-Maas (de

  16. Growth, ectomycorrhization and biochemical parameters of Quercus ...

    African Journals Online (AJOL)

    The survival of the seedlings under these drought conditions was due to two strategies: osmotic adjustment through soluble sugars and proteins accumulations in leaves and an increase in carbon discrimination which enhances the water use efficiency (WUE). Keywords: Quercus suber, growth, drought, ectomycorrhization, ...

  17. Applying Hotspot Detection Methods in Forestry: A Case Study of Chestnut Oak Regeneration

    Directory of Open Access Journals (Sweden)

    Songlin Fei

    2010-01-01

    Full Text Available Hotspot detection has been widely adopted in health sciences for disease surveillance, but rarely in natural resource disciplines. In this paper, two spatial scan statistics (SaTScan and ClusterSeer and a nonspatial classification and regression trees method were evaluated as techniques for identifying chestnut oak (Quercus Montana regeneration hotspots among 50 mixed-oak stands in the central Appalachian region of the eastern United States. Hotspots defined by the three methods had a moderate level of conformity and revealed similar chestnut oak regeneration site affinity. Chestnut oak regeneration hotspots were positively associated with the abundance of chestnut oak trees in the overstory and a moderate cover of heather species (Vaccinium and Gaylussacia spp. but were negatively associated with the abundance of hayscented fern (Dennstaedtia punctilobula and mountain laurel (Kalmia latiforia. In general, hotspot detection is a viable tool for assisting natural resource managers with identifying areas possessing significantly high or low tree regeneration.

  18. Applying Hotspot Detection Methods in Forestry: A Case Study of Chestnut Oak Regeneration

    International Nuclear Information System (INIS)

    Fei, S.

    2010-01-01

    Hotspot detection has been widely adopted in health sciences for disease surveillance, but rarely in natural resource disciplines. In this paper, two spatial scan statistics (SaT Scan and Cluster Seer) and a non spatial classification and regression trees method were evaluated as techniques for identifying chestnut oak (Quercus Montana) regeneration hotspots among 50 mixed-oak stands in the central Appalachian region of the eastern United States. Hotspots defined by the three methods had a moderate level of conformity and revealed similar chestnut oak regeneration site affinity. Chestnut oak regeneration hotspots were positively associated with the abundance of chestnut oak trees in the over story and a moderate cover of heather species (Vaccinium and Gaylussacia spp.) but were negatively associated with the abundance of hay scented fern (Dennstaedtia punctilobula) and mountain laurel (Kalmia latiforia). In general, hotspot detection is a viable tool for assisting natural resource managers with identifying areas possessing significantly high or low tree regeneration.

  19. Densities of Agrilus auroguttatus and Other Borers in California and Arizona Oaks

    Directory of Open Access Journals (Sweden)

    Laurel J. Haavik

    2014-03-01

    Full Text Available We investigated within-tree population density of a new invasive species in southern California, the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae, with respect to host species and the community of other borers present. We measured emergence hole densities of A. auroguttatus and other borers on the lower stem (bole of naïve oaks at 18 sites in southern California and on co-evolved oaks at seven sites in southeastern Arizona. We sampled recently dead oaks in an effort to quantify the community of primary and secondary borers associated with mortality—species that were likely to interact with A. auroguttatus. Red oaks (Section Lobatae produced greater densities of A. auroguttatus than white oaks (Section Quercus. On red oaks, A. auroguttatus significantly outnumbered native borers in California (mean ± SE of 9.6 ± 0.7 versus 4.5 ± 0.6 emergence holes per 0.09 m2 of bark surface, yet this was not the case in Arizona (0.9 ± 0.2 versus 1.1 ± 0.2 emergence holes per 0.09 m2. In California, a species that is taxonomically intermediate between red and white oaks, Quercus chrysolepis (Section Protobalanus, exhibited similar A. auroguttatus emergence densities compared with a co-occurring red oak, Q. kelloggii. As an invasive species in California, A. auroguttatus may affect the community of native borers (mainly Buprestidae and Cerambycidae that feed on the lower boles of oaks, although it remains unclear whether its impact will be positive or negative.

  20. After 25 years, what does the Pennsylvania Regeneration Study tell us about oak/hickory forests under stress?

    Science.gov (United States)

    William H. McWilliams; James A. Westfall; Patrick H. Brose; Shawn L. Lehman; Randall S. Morin; Todd E. Ristau; Alejandro A. Royo; Susan L. Stout

    2017-01-01

    The Pennsylvania Regeneration Study was initiated in 1989 because of concerns about a long history of stress on oak/hickory (Quercus/Carya) forests from herbivory and other factors. The study, which addresses the need for landscape-level information about regeneration quality and abundance, comprises a suite of regeneration indicator measurements...

  1. Growth and mortality of pin oak and pecan reforestation in a constructed wetland: analysis with management implications

    Science.gov (United States)

    D.E. Henderson; P. Botch; J. Cussimanio; D. Ryan; J. Kabrick; D. Dey

    2009-01-01

    Pin oak (Quercus palustris Muenchh.) and pecan (Carya illinoensis (Wangenh.) K. Koch) trees were planted on reforestation plots at Four Rivers Conservation Area in west-central Missouri. The study was conducted to determine survival and growth rates of the two species under different production methods and environmental variables....

  2. Effect of directed-spray glyphosate applications on survival and growth of planted oaks after three growing seasons

    Science.gov (United States)

    Andrew B. Self; Andrew W. Ezell; Josh L. Moree; Rory O. Thornton

    2013-01-01

    Thousands of acres of oak (Quercus spp.) plantations are established across the South annually. Survival and growth of these plantings have been less than desirable. Several techniques have been utilized in attempts to achieve improved success in these areas. One such technique that has been recommended is the application of directed-spray herbicide...

  3. Origin, development, and impact of mountain laurel thickets on the mixed-oak forests of the central Appalachian Mountains, USA

    Science.gov (United States)

    Patrick H. Brose

    2016-01-01

    Throughout forests of the northern hemisphere, some species of ericaceous shrubs can form persistent understories that interfere with forest regeneration processes. In the Appalachian Mountains of eastern North America, mountain laurel (Kalmia latifolia) may interfere in the regeneration of mixed-oak (Quercus spp.) forests. To...

  4. The potential of using coppice growth as training trees in plantations for the production of high-quality oak boles

    Science.gov (United States)

    Wayne K. Clatterbuck

    2016-01-01

    Oaks (Quercus spp.) grown in monoculture plantations often do not develop high-grade boles because all the trees grow at similar rates and crown stratification does not occur resulting in persistent branches and poor bole quality. The use of trainer species in mixed species plantations could promote interspecific competition and crown...

  5. Understory Vegetation 3 Years after Implementing Uneven-Aged Silviculture in a Shortleaf Pine-Oak Stand

    Science.gov (United States)

    Michael G. Shelton; Paul A. Murphy

    1997-01-01

    The effects of retaining overstory hardwoods on understory vegetation were determined after implementing uneven-aged silviculture usingsingle-tree selection in a shortleaf pine-oak stand (Pinus echinata Mill. and Quercus spp.) in the Ouachita Mountains. Treatments were the following hardwood basal areas (square feet per acre) and...

  6. Growth Characteristics of Ectomycorrhizal Seedlings of Quercus glauca, Quercus salicina, Quercus myrsinaefolia, and Castanopsis cuspidata Planted in Calcareous Soil

    Directory of Open Access Journals (Sweden)

    Masazumi Kayama

    2016-11-01

    Full Text Available To verify the acclimation capacity of evergreen Fagaceae species on calcareous soil, we compared ecophysiological traits between Quercus glauca Thunb., Q. salicina Blume, Q. myrsinaefolia Blume, and Castanopsis cuspidata (Thunb. Schottky as typical woody species from southwestern Japan. We also examined the inoculation effects of the ectomycorrhizal (ECM fungi Astraeus hygrometricus and Scleroderma citrinum, and planted seedlings in calcareous soil collected from a limestone quarry. We measured growth, ectomycorrhizal colonization, photosynthetic rate, and concentrations of nutrients in plant organs for A. hygrometricus-inoculated, S. citrinum-inoculated, and non-ECM seedlings. Six months after planting on calcareous soil, seedlings of the three Quercus species inoculated with A. hygrometricus were larger than non-ECM seedlings, especially Q. salicina, which showed the greatest increase in dry mass. The dry mass of C. cuspidata seedlings was inferior to that of the three Quercus species. In the nutrient-uptake analysis, phosphorus, manganese, and iron uptakes were suppressed in calcareous soil for each Fagaceae species. However, seedlings of Fagaceae species that showed better growth had increased concentrations of phosphorus in roots. We concluded that seedlings of Q. salicina and Q. glauca inoculated with A. hygrometricus were best suited to calcareous soil and were considered as useful species for the reforestation in limestone quarries.

  7. Influence of fine-scale habitat structure on nest-site occupancy, laying date and clutch size in Blue Tits Cyanistes caeruleus

    Science.gov (United States)

    Amininasab, Seyed Mehdi; Vedder, Oscar; Schut, Elske; de Jong, Berber; Magrath, Michael J. L.; Korsten, Peter; Komdeur, Jan

    2016-01-01

    Most birds have specific habitat requirements for breeding. The vegetation structure surrounding nest-sites is an important component of habitat quality, and can have large effects on avian breeding performance. We studied 13 years of Blue Tit Cyanistes caeruleus population data to determine whether characteristics of vegetation structure predict site occupancy, laying date and number of eggs laid. Measurements of vegetation structure included the density of English Oak Quercus robur, European Beech Fagus sylvatica, and other deciduous, coniferous and non-coniferous evergreen trees, within a 20-m radius of nest-boxes used for breeding. Trees were further sub-divided into specific classes of trunk circumferences to determine the densities for different maturity levels. Based on Principal Component Analysis (PCA), we reduced the total number of 17 measured vegetation variables to 7 main categories, which we used for further analyses. We found that the occupancy rate of sites and the number of eggs laid correlated positively with the proportion of deciduous trees and negatively with the density of coniferous trees. Laying of the first egg was advanced with a greater proportion of deciduous trees. Among deciduous trees, the English Oak appeared to be most important, as a higher density of more mature English Oak trees was associated with more frequent nest-box occupancy, a larger number of eggs laid, and an earlier laying start. Furthermore, laying started earlier and more eggs were laid in nest-boxes with higher occupancy rates. Together, these findings highlight the role of deciduous trees, particularly more mature English Oak, as important predictors of high-quality preferred habitat. These results aid in defining habitat quality and will facilitate future studies on the importance of environmental quality for breeding performance.

  8. Long-term effects of fire severity on oak-conifer dynamics in the southern Cascades.

    Science.gov (United States)

    Cocking, Matthew I; Varner, J Morgan; Knapp, Eric E

    2014-01-01

    We studied vegetation composition and structure in a mixed conifer-oak ecosystem across a range of fire severity 10 years following wildfire. Sample plots centered on focal California black oaks (Quercus kelloggii) were established to evaluate oak and neighboring tree and shrub recovery across a gradient of fire severity in the southern Cascade Range, USA. Shrub and oak resprouting was strongest around focal oaks where conifer mortality was greatest. Linear modeling revealed negative relationships between California black oak sprout height or basal area and residual overstory tree survival, primarily white fir (Abies concolor). The two dominant competing species, California black oak and white fir, showed opposite responses to fire severity. Sprouting California black oak and associated shrubs dominated in severely burned areas, while surviving, non-sprouting white fir maintained dominance by its height advantage and shading effects in areas that burned with low fire severity. Our results indicate that high-severity fire promotes persistence and restoration of ecosystems containing resprouting species, such as California black oak, that are increasingly rare due to widespread fire exclusion in landscapes that historically experienced more frequent fire. We present a conceptual model based on our results and supported by a synthesis of postfire resprouting dynamics literature. Our results and conceptual model help illuminate long-term postfire vegetation responses and the potential ability of fire to catalyze formation of alternate vegetation community structures that may not be apparent in studies that evaluate postfire effects at shorter time-since-fire intervals or at coarser scales.

  9. Oaks and Environmental Education

    Science.gov (United States)

    Kay Antunez de Mayolo

    1991-01-01

    A number of educational projects which focus on youth awareness and involvement with California oaks have been developed during the last five years. Primarily used in urban areas where oak populations have declined, many of these programs promote seedling propagation, tree planting and help to develop student understanding of environmental issues involving oaks while...

  10. People and oaks

    Science.gov (United States)

    Paul F. Starrs

    2015-01-01

    While technical knowledge of oaks, acorns, habitat, wildlife, and woodland environments is evolving and a sought-after field of study, there are profound linkages, at once humanistic and artistic, where it comes to people and oaks. Looking at six distinct facets of humans and oak woodlands, this essay suggests that the bonds of people to place can be mediated by the...

  11. El ciclo del potasio en dehesas de Quercus rotundifolia y Quercus pyrenaica

    OpenAIRE

    Escudero Berián, Alfonso; García Criado, Balbino; Alonso Peloche, Herminio

    1985-01-01

    Hemos estudiado el ciclo del potasio en dehesas de Quercus rotundifolia Lam. y Quercus pyrenaica Willd. de la provincia de Salamanca. El potasio es el elemento que se transfiere en mayores proporciones a través de frutos y de material herbáceo, que son materias altamente digestibles. Por ello, su transferencia al subsistema herbívoro es mayor que para los restantes nutrientes. El potasio es también el macronutriente más intensamente extraído de los tejidos vegetables por el ...

  12. Experimental minimum threshold for Phytophthora cinnamomi root disease expression on Quercus suber

    Directory of Open Access Journals (Sweden)

    María Socorro SERRANO

    2015-12-01

    Full Text Available Quercus suber seedlings were potted in soils infested with increasing concentrations of Phytophthora cinnamomi chlamydospores and submitted to weekly flooding for 3 months to favour root infections. Increasing quantities of chlamydospores led to an exponential increase in their ability to germinate. Root symptoms (necrosis and/or absence of feeder roots were significantly more severe than those recorded in uninfested soil only for plants potted in soils infested with 61 cfu g-1 or more. Although generated using potting mix, this minimum threshold represents a tool for checking the potential infectivity of infested soils or to assess the effectiveness of some control methods to reduce soil inoculum. However, a low level of root infection was recorded even at 3 cfu g-1. Therefore, long-term disease risk may be present whenever the pathogen is detectable in oak forest soils.

  13. Dry deposition of sulfate to Quercus rubra and Liriodendron tulipifera foliage

    International Nuclear Information System (INIS)

    Vandenberg, J.J.

    1987-01-01

    Estimates were made of the rate of dry deposition to red oak (Quercus rubra) and tulip poplar (Liriodendron tulipifera) foliage. In the laboratory, radioactive ammonium sulfate aerosols were generated in an exposure chamber. These aerosols were dry deposited onto leaves that were sequentially washed to examine the efficacy of washing procedures in removal of surface deposits. Over 90% of dry deposited sulfate was removed after a 30 second wash duration. Laboratory procedures also estimated the magnitude of foliar sulfur that leached into leaf wash solutions. The majority of laboratory leaves demonstrated no leaching of sulfur from the internal pool. However, some leaves showed significant sulfur leaching. It was concluded that leaching of internal sulfur was highly leaf specific. This indicated that each leaf used in field experiments needed to be individually examined for leaching

  14. Warm-cold colonization: response of oaks to uplift of the Himalaya-Hengduan Mountains.

    Science.gov (United States)

    Meng, Hong-Hu; Su, Tao; Gao, Xiao-Yang; Li, Jie; Jiang, Xiao-Long; Sun, Hang; Zhou, Zhe-Kun

    2017-06-01

    Clarifying the relationship between distribution patterns of organisms and geological events is critical to understanding the impact of environmental changes on organismal evolution. Quercus sect. Heterobalanus is now distributed across the Himalaya-Hengduan Mountains (HHM) and warm lowland in East China, yet how the distribution patterns of this group changed in response to the HHM uplift remains largely unknown. This study examines the effect of tectonic events in the HHM region on the oaks, providing a biological perspective on the geological history of this region. Fifty-six populations of Quercus sect. Heterobalanus were genotyped using four chloroplast DNA regions and nine nuclear simple sequence repeat loci to assess population structure and diversity, supplemented by molecular dating and ancestral area reconstructions. The underlying demographic dynamics were compared using ecological niche models of the species distributions during the last glacial maximum and the present. These analyses illustrate that Quercus sect. Heterobalanus diversified as the HHM uplifted and climatic cooling during the mid-Miocene, colonizing the cold habitats from warm broadleaf mixed forests. Lineages in cold highlands and warm lowlands have diverged as a consequence of local adaptation to diverging climates since the late Miocene. Our results suggest that continuous uplift of the HHM in the late Miocene to early Pliocene accompanied by simultaneous cooling triggered the differentiation of oaks. The biogeography of Quercus sect. Heterobalanus illuminates the geological events responsible for the modern-day HHM. © 2017 John Wiley & Sons Ltd.

  15. Using Paleoecology to Inform Land Management as Climates Change: An Example from an Oak Savanna Ecosystem

    Science.gov (United States)

    Spencer, Jessica D.; Brunelle, Andrea; Hepola, Tim

    2017-12-01

    Oak savanna, a transitional ecosystem between open prairie and dense oak forest, was once widespread in Minnesota. Upon European settlement much of the oak savanna was destroyed. Recently, efforts to restore this ecosystem have increased and often include the reintroduction of fire. Though fire is known to serve an important role within oak savannas, there are currently few studies which address fire regimes on timescales longer than the last century. This research presents a paleoecological history of Sherburne National Wildlife Refuge (SNWR) in MN, USA, spanning the last 8000 years. The objectives of this study were to use charcoal, pollen, and magnetic susceptibility of lake sediments collected from Johnson Slough (JS) within the refuge to evaluate the natural range of variability and disturbance history of the oak savanna within the refuge, assess the success of current restoration strategies, and add to the regional paleoecological history. The mid/late Holocene period of the JS record shows a period of high fire activity from ca. 6500 to 2600 cal year BP, with a shift from prairie to oak savanna occurring over this same period. A (possibly agricultural) disturbance to JS sediments affected the period from ca. 2600 cal year BP to 1963 AD, which includes the time of Euro-American settlement. However, the destruction and subsequent restoration of the oak savanna is evident in a pollen ratio of Quercus:Poaceae, indicating that current restoration efforts have been successful at restoring the oak savanna to within the natural range of variability seen just prior to destruction.

  16. Oaks were the historical foundation genus of the east-central United States

    Science.gov (United States)

    Hanberry, Brice B.; Nowacki, Gregory J.

    2016-08-01

    Foundation tree species are dominant and define ecosystems. Because of the historical importance of oaks (Quercus) in east-central United States, it was unlikely that oak associates, such as pines (Pinus), hickories (Carya) and chestnut (Castanea), rose to this status. We used 46 historical tree studies or databases (ca. 1620-1900) covering 28 states, 1.7 million trees, and 50% of the area of the eastern United States to examine importance of oaks compared to pines, hickories, and chestnuts. Oak was the most abundant genus, ranging from 40% to 70% of total tree composition at the ecological province scale and generally increasing in dominance from east to west across this area. Pines, hickories, and chestnuts were co-dominant (ratio of oak composition to other genera of definition, were not foundational. Although other genera may be called foundational because of localized abundance or perceptions resulting from inherited viewpoints, they decline from consideration when compared to overwhelming oak abundance across this spatial extent. The open structure and high-light conditions of oak ecosystems uniquely supported species-rich understories. Loss of oak as a foundation genus has occurred with loss of open forest ecosystems at landscape scales.

  17. Studies on Wound Healing Properties of Quercus infectoria ...

    African Journals Online (AJOL)

    Purpose: The aim of the present study was to investigate the wound healing activity of the selected Indian medicinal plant Quercus infectoria. Method: Ethanol extract of the shade-dried leaves of Quercus infectoria was studied for its effect on wound healing in rats, using incision, excision and dead-space wound models, ...

  18. The negative impact of intentionally introduced Quercus rubra L. on a forest community

    Directory of Open Access Journals (Sweden)

    Beata Woziwoda

    2014-03-01

    Full Text Available Some alien woody species used in commercial forestry become invasive and, as invaders, cause major problems in natural and semi-natural ecosystems. However, the deliberate introduction of aliens can bring unintended negative changes also within areas of their cultivation. This paper presents the effects of the intentional introduction of the North-American Quercus rubra in European mixed Scots pine-Pedunculate oak forests (POFs: Querco roboris-Pinetum (W. Mat. 1981 J. Mat. 1988. Phytosociological data from field research combined with GIS data analysis of the current distribution of Northern Red oak in the studied habitat were used to determine the composition and structure of forest communities in plots with and without Q. rubra participation.  The results show that Q. rubra significantly reduces native species richness and abundance, both in old-growth and in secondary (post-agricultural forests. Not one resident vascular plant benefits from the introduction of Northern Red oak and only a few are able to tolerate its co-occurrence. The natural restocking of all native woody species is also strongly limited by this alien tree.  The introduction of Northern Red oak significantly limits the environmental functions of the POF ecosystem and weakens its economic and social aspects. However, its further cultivation is justified from an economic point of view, as the essential function of the studied forests is commercial timber production, and the introduction of this fast growing alien tree supports the provisioning ecosystem services. A clear description of the level of trade-off between the accepted negative and positive effects of the introduction of Q. rubra on forest ecosystem services requires further interdisciplinary studies.

  19. Quercus suber range dynamics by ecological niche modelling: from the Last Interglacial to present time

    Science.gov (United States)

    Vessella, Federico; Simeone, Marco Cosimo; Schirone, Bartolomeo

    2015-07-01

    Ecological Niche Modelling (ENM) is widely used to depict species potential occurrence according to environmental variables under different climatic scenarios. We tested the ENM approach to infer past range dynamics of cork oak, a keystone species of the Mediterranean Biome, from 130 ka to the present time. Hindcasting implications would deal with a better species risk assessment and conservation management for the future. We modelled present and past occurrence of cork oak using seven ENM algorithms, starting from 63,733 spatially unique presence points at 30 arc-second resolution. Fourteen environmental variables were used and four time slices were considered (Last Interglacial, Last Glacial Maximum, mid-Holocene and present time). A threshold-independent evaluation of the goodness-of-fit of the models was evaluated by means of ROC curve and fossil or historical evidences were used to validate the results. Four weighted average maps depicted the dynamics of area suitability for cork oak in the last 130 ka. The derived species autoecology allowed its long-term occurrence in the Mediterranean without striking range reduction or shifting. Fossil and historical post-processing validation support the modelled past spatial extension and a neglected species presence at Levantine until the recent time. Despite the severe climatic oscillation since the Last Glacial Maximum, cork oak potential distribution area experienced limited range changes, confirming its strong link with the Mediterranean Basin. The ecological amplitude of Quercus suber could be therefore adopted as a reference to trace the Mediterranean bioclimate area. A better knowledge of the past events of Mediterranean vegetation, a wider range of study species and environmental determinants are essential to inform us about its current state, its sensitivity to human impact and the potential responses to future changes.

  20. Fragmentation patterns of evergreen oak woodlands in Southwestern Iberia: identifying key spatial indicators.

    Science.gov (United States)

    Costa, Augusta; Madeira, Manuel; Lima Santos, José; Plieninger, Tobias; Seixas, Júlia

    2014-01-15

    Mediterranean evergreen oak woodlands (composed of Quercus suber L. and Quercus rotundifolia Lam.) are becoming increasingly fragmented in the human-modified landscapes of Southwestern Portugal and Spain. Previous studies have largely neglected to assess the spatial changes of oak woodlands in relation to their surrounding landscape matrix, and to characterize and quantify woodland boundaries and edges. The present study aims to fill this gap by analyzing fragmentation patterns of oak woodlands over a 50-year period (1958-2007) in three landscapes. Using archived aerial imagery from 1958, 1995 and 2007, for two consecutive periods (1958-1995 and 1995-2007), we calculated a set of landscape metrics to compare woodland fragmentation over time. Our results indicated a continuous woodland fragmentation characterized by their edge dynamics. From 1958 to 2007, the replacement of open farmland by shrubland and by new afforestation areas in the oak woodland landscape surrounding matrix, led to the highest values for edge contrast length trends of 5.0 and 12.3, respectively. Linear discriminant analysis was performed to delineate fragmented woodland structures and identify metric variables that characterize woodland spatial configuration. The edge contrast length with open farmland showed a strong correlation with F1 (correlations ranging between 0.55 and 0.98) and may be used as a proxy for oak woodland mixedness in landscape matrix. The edge dynamics of oak woodlands may result in different patterns of oak recruitment and therefore, its study may be helpful in highlighting future baselines for the sustainable management of oak woodlands. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. A Pleistocene clone of Palmer's oak persisting in Southern California.

    Directory of Open Access Journals (Sweden)

    Michael R May

    Full Text Available BACKGROUND: The distribution of Palmer's oak (Quercus palmeri Engelm. includes numerous isolated populations that are presumably relicts of a formerly larger range that has contracted due to spreading aridity following the end of the Pleistocene. PRINCIPAL FINDINGS: We investigated a recently discovered disjunct population of Palmer's oak in the Jurupa Mountains of Riverside County, California. Patterns of allozyme polymorphism, morphological homogeneity, widespread fruit abortion, and evidence of fire resprouting all strongly support the hypothesis that the population is a single clone. The size of the clone and estimates of annual growth from multiple populations lead us to conclude that the clone is in excess of 13,000 years old. CONCLUSIONS: The ancient age of the clone implies it originated during the Pleistocene and is a relict of a vanished vegetation community. Range contraction after climate change best explains the modern disjunct distribution of Q. palmeri and perhaps other plants in California.

  2. Control Efficacy of Fungicide Injection on Oak Wilt in the Field

    Directory of Open Access Journals (Sweden)

    Su-Yeon Son

    2014-12-01

    Full Text Available Oak wilt caused by Raffaelea quercus-mongolicae was first noticed in South Korea in 2004 and, ever since, its distribution and damage have been increasing. To screen a fungicide effective for oak wilt control by tree injection, laboratory and field experiments were conducted. Ten fungicides and one antibiotic were examined in vivo for their effectiveness in restricting the growth of R. quercus-mongolicae and R. quercivora (Japanese oak wilt pathogen isolates. To the Korean isolates of R. quercus-mongolicae, chlorothalonil showed the highest fungicidal effects, followed by benomyl and propiconazole. To the Japanese one, propiconazole was highest in the fungicidal effectiveness, followed by benomyl and bitertanol. Propiconazole was selected for field-testing of its control efficacy because it showed good fungicidal effects in vitro and systemic activity. The control efficacy in the field was 87.5% in the first year of injection and 66.7% in the second year, indicating the fungicidal effects last at least over one year.

  3. Germination of hyphal bodies of Pythium spiculum isolated from declining cork oaks at Doñana National Park (Spain

    Directory of Open Access Journals (Sweden)

    PAOLO DE VITA

    2012-01-01

    Full Text Available Pythium spiculum, a recently described new taxon, has been isolated from declining cork oaks (Quercus suber L. at Doñana National Park (south-western Spain. The microorganism can infect and cause root disease in Quercus, but currently it is unknown whether its hyphal bodies can germinate and infect host trees. These hyphal bodies, regardless of shape, have been shown to be able to germinate, producing long germ tubes, sometimes ramified. Zoospore production was not recorded, but hyphal bodies are potential host infective structures in dry soil conditions.

  4. Log-grade volume distribution prediction models for tree species in red oak-sweetgum stands on US mid-south minor stream bottoms

    Science.gov (United States)

    George M. Banzhaf; Thomas G. Matney; Emily B. Schultz; James S. Meadows; J. Paul Jeffreys; William C. Booth; Gan Li; Andrew W. Ezell; Theodor D. Leininger

    2016-01-01

    Red oak (Quercus section Labatae)-sweetgum (Liquidambar styraciflua L.) stands growing on mid-south bottomland sites in the United States are well known for producing high-quality grade hardwood logs, but models for estimating the quantity and quality of standing grade wood in these stands have been unavailable. Prediction...

  5. Stand-level growth and yield component models for red oak-sweetgum forests on Mid-South minor stream bottoms

    Science.gov (United States)

    Emily B. Schultz; J. Clint Iles; Thomas G. Matney; Andrew W. Ezell; James S. Meadows; Theodor D. Leininger; al. et.

    2010-01-01

    Greater emphasis is being placed on Southern bottomland hardwood management, but relatively few growth and yield prediction systems exist that are based on sufficient measurements. We present the aggregate stand-level expected yield and structural component equations for a red oak (Quercus section Lobatae)-sweetgum (Liquidambar styraciflua L.) growth and yield model....

  6. Assessing anthropogenic and natural disturbances: forest response to similarly aged clearcut and tornado disturbances in an east Tennessee oak-hickory forest

    Science.gov (United States)

    Jonathan C. McGrath; Wayne K. Clatterbuck

    2013-01-01

    In February of 1993, an F3 tornado caused a large-scale disturbance in an east Tennessee oak-hickory (Quercus spp.-Carya spp.) forest. Vegetation response to anthropogenic and natural disturbances was compared by examining two tornado-disturbed areas and five adjacent 1-acre silvicultural clearcut areas unaffected by the tornado...

  7. Evaluation of stem water potential and other tree and stand variables as risk factors for Phytophthora ramorum canker development in coast live oak

    Science.gov (United States)

    Tedmund J. Swiecki; Elizabeth Bernhardt

    2002-01-01

    We conducted a case-control study to examine the role of water stress and various other factors on the development of Phytophthora ramorum cankers in symptomatic (case) and symptomless (control) coast live oak (Quercus agrifolia) and tanoak (Lithocarpus densiflorus). Midday stem water potential (SWP) in ...

  8. Partitioning of current photosynthate to different chemical fractions in leaves, stems, and roots of northern red oak seedlings during episodic growth

    Science.gov (United States)

    Richard E. Dickson; Patricia T. Tomlinson; J. G. Isebrands

    2000-01-01

    The episodic or flushing growth habit of northern red oak (Quercus rubra L.,) has a significant influence on carbon fixation, carbon transport from source leaves, and carbon allocation within the plant; however, the impact of episodic growth on carbon parciprioning among chemical fractions is unknown. Median-flush leaves of the first and second flush...

  9. An evaluation of seven methods for controlling mountain laurel thickets in the mixed-oak forests of the central Appalachian Mountains, USA

    Science.gov (United States)

    Patrick H. Brose

    2017-01-01

    In the Appalachian Mountains of eastern North America, mountain laurel (Kalmia latifolia) thickets in mixed-oak (Quercus spp.) stands can lead to hazardous fuel situations, forest regeneration problems, and possible forest health concerns. Therefore, land managers need techniques to control mountain laurel thickets and limit...

  10. The effect of acorn insects on the establishment and vigor of northern red oak seedlings in north-central West Virginia

    Science.gov (United States)

    Linda S. Gribko

    1995-01-01

    During a 2-year investigation into the effect of small mammals on northern red oak (Quercus rubra) acorn survival and germination, widespread germination failure and lack of seedling vigor was apparent in control quadrats on one of two watersheds under study. Insects were present in and on the failed acorns but it was unknown whether they were...

  11. Impacts of elevated atmospheric CO2 on litter quality, litter decomposability and nitrogen turnover rate of two oak species in a Mediterranean forest ecosystem

    NARCIS (Netherlands)

    Fayez Raiesi Gahrooee,

    1998-01-01

    Elevated CO2 may affect litter quality of plants, and subsequently C and N cycling in terrestrial ecosystems, but changes in litter quality associated with elevated CO2 are poorly known. Abscised leaf litter of two oak species (Quercus cerris L., and Q. pubescens Willd.) exposed to long-term

  12. Blue lesions.

    Science.gov (United States)

    Longo, Caterina; Scope, Alon; Lallas, Aimilios; Zalaudek, Iris; Moscarella, Elvira; Gardini, Stefano; Argenziano, Giuseppe; Pellacani, Giovanni

    2013-10-01

    Blue color is found in a wide range of malignant and benign melanocytic and nonmelanocytic lesions and in lesions that result from penetration of exogenous materials, such as radiation or amalgam tattoo or traumatic penetration of particles. Discriminating between different diagnostic entities that display blue color relies on careful patient examination and lesion assessment. Dermoscopically, the extent, distribution, and patterns created by blue color can help diagnose lesions with specificity and differentiate between benign and malignant entities. This article provides an overview of the main diagnoses whereby blue color can be found, providing simple management rules for these lesions. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Characterization of volatile constituents in commercial oak wood chips.

    Science.gov (United States)

    Fernández de Simón, Brígida; Muiño, Iria; Cadahía, Estrella

    2010-09-08

    The volatile composition of the different oak wood pieces (chips of Quercus spp.) that can be found on the market to be used as alternatives to barrels for aging wines, as well as of chips of Quercus pyrenaica which are being introduced, was studied, evaluating the contents of volatile phenols, lactones, furanic compounds, pyranones, phenolic aldehydes, phenolic ketones, and others. In regard to the overall results, the volatile composition of these products varies widely and has not been clearly laid out according to either the oak species or the wood toasting intensity. Taking into account that the different characteristics of alternatives to barrel products are reflected in the wine treated with them and that an oenological profile based on these variables (origin and toasting level) cannot be defined, only an appropriate chemical analysis would reveal the quality of alternative-to-barrel products and allow us to attempt to foresee its effects on the chemical and organoleptic characteristics of the wines treated with them. On the other hand, the Q. pyrenaica alternative products are very similar to those of other species, with some aromatic particularities, such as their high levels of furanic compounds, eugenol, Furaneol, and cis-whiskylactone, and low levels of vanillin.

  14. A comparative analysis of stomata and leaf trichome characteristics in Quercus robur L. genotypes

    Directory of Open Access Journals (Sweden)

    Nikolić Nataša P.

    2003-01-01

    Full Text Available The objective of this study was to determine genotype variability of leaf trichome and stoma characteristics. Leaves were sampled from seventeen pedunculate oak (Quercus robur L genotypes originating from clonal seed orchard Banov Brod (Srem, the Vojvodina Province. The pedunculate oak has hypostomatal leaves. Statistically significant differences were found for the dimensions and density of stomata. Genotype variability of stomatal dimensions was less pronounced in comparison with their density (CV = 8.88%. Stomata number ranged from 530 to 791 per mm2 of leaf area; genotypes 18 and 25 could be distinguished from the others for the highest stomata number per leaf unit area, genotype 35 for the lowest number. In all genotypes, only solitary eglandular trichomes were observed on the adaxial leaf surface while both solitary eglandular and uniseriate glandular hairs were present on the abaxial surface. Single glandular trichomes were observed in all genotypes, while some of them were characterized by the presence of two (genotypes 4, 5, 6, 16, 22, 25, 28, 29, 30, 35, 38, 40, and 85 or three (genotypes 16, 25, 35 hairs joined by their basal cells.

  15. Studies on the ectomycorrhizal community in a declining Quercus suber L. stand.

    Science.gov (United States)

    Lancellotti, Enrico; Franceschini, Antonio

    2013-10-01

    This survey was carried out in a Quercus suber L. stand with many trees affected by the disease "oak decline". Its aim was to obtain information about both the belowground ectomycorrhizal fungal community in a declining Q. suber stand as a whole, and the ectomycorrhizal fungal community of individual tree (EFT) detected in healthy and diseased plants. To this end, we first categorized the trees into four different decline classes (one for healthy plants and three for diseased plants) and then, by using morphological and molecular tools, we identified the ectomycorrhizas isolated from samples collected near the trees with different declining classes. The ectomycorrhizal community as a whole was seen to be composed of numerous ectomycorrhizal fungal species, only some of which appeared to be dominant (Cenococcum geophilum, Lactarius chrysorrheus, and some species of Tomentella genus), while most occurred sporadically. Results show that all root tips observed are mycorrhized and that decline class does not influence the number of ectomycorrhizal root tips found in the EFTs, thus oak decline does not impact the investment in ectomycorrhizal symbiosis. However, some statistical differences can be observed in the values of evenness and taxonomic distinctness in the EFT associated with trees with different states of health. Finally, both the analysis of similarity test and the ordination technique highlight a compositional difference between the EFT associated with trees in different health conditions, but also suggest that other factors may play a role in causing these differences.

  16. Rooting Responses of Three Oak Species to Low Oxygen Stress

    Science.gov (United States)

    Karel A. Jacobs; James D. MacDonald; Alison M. Berry; Laurence R. Costello

    1997-01-01

    Rooting characteristics were compared in blue (Q. douglasii), valley (Q. lobata), and cork oak (Q. suber) seedlings under hypoxic (low oxygen) conditions. A 50 percent reduction in root growth occurred in all species at an oxygen level of 4 percent, or an oxygen diffusion rate of 0.3 mg cm-2...

  17. Laurels for Laurel Oaks

    Science.gov (United States)

    Sisson, Ray

    1976-01-01

    Describes a former Air Force base converted into a joint school district vocational school which includes among other things an up-to-date facility for the students, located at Laurel Oaks, one of the four campuses of the Great Oaks Joint Vocational School District. (HF)

  18. Characterization of Acorn Fruit Oils Extracted from Selected Mediterranean Quercus Species

    Directory of Open Access Journals (Sweden)

    Al-Rousan, W. M.

    2013-12-01

    Full Text Available The present study is aimed to identifying the acorn fruit oil composition of three Mediterranean white oak group species, Quercus aegilops (QA, Quercus infectoria (QI, and Quercus calliprinus (QC. Samples were estimated for the oil contents of acorn fruits, oil chemical and physical constants, fatty acid profile, tocopherols, phenolic compounds, and sterols.The oil content, expressed as dry weight, was found to be 3.40-7.51%. The physical and chemical constants included specific gravity 0.912-0.922, refractive index 1.4529-1.4645, specific extinction at 232 nm 2.497-2.536 and at 270 nm 1.495-2.037, iodine value 75.2-87.6, and saponification value 192.6-219.4. The fatty acid compositions were determined by GC as methyl esters. The most abundant fatty acids were oleic (53.3-56.1%, linoleic 21.3-23.4%, palmitic 17.8-18.7%, linolenic 1.5-1.6% and stearic acid 1.02-1.60%. The Tocopherol content was high in the range of 1440-1783 mg kg-1, γ-tocopherol constituted 84-91% of total tocopherols. Phenolic compounds were in remarkable amounts in all the three species 84-109 mg gallic acid kg-1 oil. Total sterol contents were between 2040-2480 mg kg-1 oil, with β-sitosterol being the main component comprising of 77.20-84.61%, followed by ∆5-avenasterol (5.8-11.4%, campesterol (3.6-4.5%, and stigmasterol (2.6-3.8. The cholesterol content was relatively high (0.42-0.55%.El presente estudio tuvo como objetivo identificar la composición de aceites de bellota de tres especies del grupo del roble blanco del Mediterráneo, Quercus Aegilops (QA, Quercus infectoria (QI y Quercus calliprinus (QC. Las muestras fueron evaluadas por el contenido de aceite, parámetros físico-químicos del aceite, perfil de ácidos grasos, tocoferoles, compuestos fenólicos y esteroles. El contenido de aceite, expresado en peso seco encontrado fue de 3,40 a 7,51%. Las constantes físico-químicas fueron: densidad 0,912-0,922, índice de refracción 1,4529 a 1,4645, extinción espec

  19. Demography and recruitment limitations of three oak species in California.

    Science.gov (United States)

    Tyler, Claudia M; Kuhn, Bill; Davis, Frank W

    2006-06-01

    We review published studies on the demography and recruitment of California oak trees and focus on the widespread dominant species of the foothill woodlands, Quercus douglasii, Q. lobata, and Q. agrifolia, to ascertain the nature and strength of evidence for a decline in populations of these species. The vast majority of studies have been of short duration (less than three years), focused on the acorn and seedling life stages, and conducted at few locations within each species geographic range. We summarize the extensive body of research that has been conducted on the biological and physical factors that limit natural seedling recruitment of oaks. The oak "regeneration problem" has largely been inferred from current stand structure rather than by demographic analyses, which in part reflects the short-term nature of most oak research. When viewed over longer periods of time usingfield surveys or historical photos, the evidence for a regeneration problem in foothill oaks is mixed. Q. douglasii shows very limited seedling or sapling recruitment at present, but longer term studies do not suggest a decline in tree density, presumably because rare recruitment is sufficient to offset low rates of mortality of overstory individuals. Q. agrifolia appears to be stable or increasing in some areas, but decreasing in areas recently impacted by the disease Phytophthora ramorum. Evidence from the few available studies is more consistent in suggesting long-term declines in foothill populations of Q. lobata. Long-term monitoring, age structure analysis, and population models are needed to resolve the current uncertainty over the sustainability of oak woodlands in California.

  20. Comparison of the autoecology of Quercus robur L. and Q. petraea (Mattuschka Liebl. stands in the Northwest of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    A. Rodriguez-Campos

    2010-09-01

    Full Text Available The purpose of the present work is to characterize the functioning of the ecosystems of semideciduous and deciduous Atlantic oaks in the northwest of the Iberian Peninsula. The studied species were: Quercus robur L. and Quercus petraea (Mattuschka Liebl. To advance in the knowledge of the autecology of these species it is necessary to descend at the regional level and describe in detail the variability of the environment to determine their potential, and to decide the silvicultural treatments to be applied to preserve them and to analyze future actuations in order to a possible expansion. The analysis of the results allows knowing differences in continentalityand site conditions, with more precipitation, soil variability and humidification in Q. petraea forests respect to Q. robur. These information represent appropriate measures for the sustainable and multifunctional management of these forests, useful as indicators environmental and forestry parameters as well as the conservationstatus of these formations.

  1. Model of the PCB and mercury exposure of mink and great blue heron inhabiting the off-site environment downstream from the US Department of Energy Oak Ridge Reservation

    Energy Technology Data Exchange (ETDEWEB)

    MacIntosh, D.L. (Indiana Univ., Bloomington, IN (United States). School of Public and Environmental Affairs); Suter, G.W. II; Hoffman, F.O. (Oak Ridge National Lab., TN (United States))

    1992-09-01

    This report presents a pair of wildlife exposure models developed for use in investigating the risks to wildlife of releases of mercury and PCBS. The species modeled are the great blue heron and mink The models may be used to estimate the exposure experienced by mink and herons, to help establish remedial action goals and to identify research needs. Because mercury and PCBs bioaccumulate through dietary uptake, the models simulate the food webs supporting the two species. Sources of contaminants include surface water, sediment, sediment pore water, and soil. The model are stochastic equilibrium models. Two types of variance in the input parameters are distinguished: stochastic variance among individual mink and herons and ignorance concerning true parameter values. The variance in the output due to stochastic parameters indicates the expected variance among the receptors. The variance due to ignorance indicates the extent to which the model outputs could be unpaved by additional sampling and measurement. The results of the models were compared to concentrations measured in great blue heron eggs and nestlings from colonies on the Clinch and Tennessee Rivers. The predicted concentrations agreed well with the measured concentrations. In addition, the variances in measured values among individuals was approximately equal to the total stochastic variance predicted by the models.

  2. Model of the PCB and mercury exposure of mink and great blue heron inhabiting the off-site environment downstream from the US Department of Energy Oak Ridge Reservation. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    MacIntosh, D.L. [Indiana Univ., Bloomington, IN (United States). School of Public and Environmental Affairs; Suter, G.W. II; Hoffman, F.O. [Oak Ridge National Lab., TN (United States)

    1992-09-01

    This report presents a pair of wildlife exposure models developed for use in investigating the risks to wildlife of releases of mercury and PCBS. The species modeled are the great blue heron and mink The models may be used to estimate the exposure experienced by mink and herons, to help establish remedial action goals and to identify research needs. Because mercury and PCBs bioaccumulate through dietary uptake, the models simulate the food webs supporting the two species. Sources of contaminants include surface water, sediment, sediment pore water, and soil. The model are stochastic equilibrium models. Two types of variance in the input parameters are distinguished: stochastic variance among individual mink and herons and ignorance concerning true parameter values. The variance in the output due to stochastic parameters indicates the expected variance among the receptors. The variance due to ignorance indicates the extent to which the model outputs could be unpaved by additional sampling and measurement. The results of the models were compared to concentrations measured in great blue heron eggs and nestlings from colonies on the Clinch and Tennessee Rivers. The predicted concentrations agreed well with the measured concentrations. In addition, the variances in measured values among individuals was approximately equal to the total stochastic variance predicted by the models.

  3. Model of the PCB and mercury exposure of mink and great blue heron inhabiting the off-site environment downstream from the US Department of Energy Oak Ridge Reservation

    International Nuclear Information System (INIS)

    MacIntosh, D.L.

    1992-09-01

    This report presents a pair of wildlife exposure models developed for use in investigating the risks to wildlife of releases of mercury and PCBS. The species modeled are the great blue heron and mink The models may be used to estimate the exposure experienced by mink and herons, to help establish remedial action goals and to identify research needs. Because mercury and PCBs bioaccumulate through dietary uptake, the models simulate the food webs supporting the two species. Sources of contaminants include surface water, sediment, sediment pore water, and soil. The model are stochastic equilibrium models. Two types of variance in the input parameters are distinguished: stochastic variance among individual mink and herons and ignorance concerning true parameter values. The variance in the output due to stochastic parameters indicates the expected variance among the receptors. The variance due to ignorance indicates the extent to which the model outputs could be unpaved by additional sampling and measurement. The results of the models were compared to concentrations measured in great blue heron eggs and nestlings from colonies on the Clinch and Tennessee Rivers. The predicted concentrations agreed well with the measured concentrations. In addition, the variances in measured values among individuals was approximately equal to the total stochastic variance predicted by the models

  4. Impact of stereoide fungi on decomposition of oak wood and possibility of its protection

    Directory of Open Access Journals (Sweden)

    Mirić Milenko

    2005-01-01

    Full Text Available Four stereoide fungi, causers of decay of oak wood, have been investigated as follows: Stereum hirsutum, Chondrostereum purpureum, Stereum rugosum and Xylobolus frustulatus. The field tests have been undertaken in order to determine the influence of the stereoide fungi on the wood of Sessile oak (Quercus petraea and Austrian oak (Quercus robur. Artificial inoculations with mycelia have been provoked in vital standing trees, as well as in laying trunks. The appearance of dying back symptoms, the rate of mycelia spread through the stem, speed of wound callusing and appearance of fruit bodies or decay symptoms, have been observed. The protection possibility of trunks has been tested as well by using preservatives based on chromo-cupric boron salts, dichlorfluanide and chlorinepyriphos, cupric naphtenates, as well as with antiseptic paste. Microscopically analysis of attacked oak wood has been performed by utilizing of scanning electron (SEM and standard optical microscope providing normal, fluorescence, polarized and UV light, so that anatomical changes of the wood structure elements influenced by fungal activity have been noted.

  5. Associations between growth, wood anatomy, carbon isotope discrimination and mortality in a Quercus robur forest.

    Science.gov (United States)

    Levanic, Tom; Cater, Matjaz; McDowell, Nate G

    2011-03-01

    Observations of forest mortality are increasing globally, but relatively little is known regarding the underlying mechanisms driving these events. Tree rings carry physiological signatures that may be used as a tool for retrospective analyses. We capitalized on a local soil water drainage event in 1982 that resulted in increased mortality within a stand of oak trees (Quercus robur), to examine the underlying physiological patterns associated with survival and death in response to soil water limitations. Pre-dawn water potentials showed more negative values for trees in the process of dying compared with those that survived. We used tree rings formed over the 123 years prior to mortality to estimate productivity from basal area increment (BAI, mm(2)), multiple xylem hydraulic parameters via anatomical measurements and crown-level gas exchange via carbon isotope discrimination (Δ, ‰). Oaks that died had significantly higher BAI values than trees that survived until the drainage event, after which the BAI of trees that died declined dramatically. Hydraulic diameter and conductivity of vessels in trees that died were higher than in surviving trees until the last 5 years prior to mortality, at which time both groups had similar values. Trees that died had consistently lower Δ values than trees that survived. Therefore, tree mortality in this stand was associated with physiological differences prior to the onset of soil water reduction. We propose that trees that died may have been hydraulically underbuilt for dry conditions, which predisposes them to severe hydraulic constraints and subsequent mortality. Measurements of above-ground/below-ground dry mass partitioning will be critical to future tests of this hypothesis. Based on these results, it is probable that pedunculate oak trees will experience greater future mortality if climate changes cause more severe droughts than the trees have experienced previously.

  6. Characterization of Quercus species distributed in Jordan using ...

    African Journals Online (AJOL)

    Characterization of Quercus species distributed in Jordan using morphological and molecular markers. Mohammad S Jawarneh, Mohammad H Brake, Riyadh Muhaidat, Hussein M Migdadi, Jamil N Lahham, Ahmad Ali El-Oqlah ...

  7. Fitting Fire into Oak Management

    Science.gov (United States)

    Patrick Brose

    2004-01-01

    In the past decade, the use of prescribed fire in the mixed-oak forests of the eastern United States has markedly increased to help overcome the chronic lack of abundant, vigorous oak regeneration (Yaussy 2000). However, pre- scribed burns implemented under inappropriate circum- stances can result in failure to establish oak regeneration and/or loss of existing oak...

  8. Wood anatomical parameters of lowland European oak and Scots pine as proxies for climate reconstructions

    Science.gov (United States)

    Balanzategui, Daniel; Heußner, Karl-Uwe; Wazny, Tomasz; Helle, Gerd; Heinrich, Ingo

    2017-04-01

    Tree-ring based temperature reconstructions from the temperate lowlands worldwide are largely missing due to diffuse climate signals so far found in tree-ring widths. This motivated us to concentrate our efforts on the wood anatomies of two common European tree species, the European oak (Quercus robur) and Scots pine (Pinus sylvestris). We combined core samples of living trees with archaeological wood from northern Germany and Poland. We measured approx. 46,000 earlywood oak vessels of 34 trees covering the period AD 1500 to 2016 and approx. 7.5 million pine tracheid cells of 41 trees covering the period AD 1300 to 2010. First climate growth analyses indicate that both oak earlywood vessel and pine tracheid parameters contain climate signals which are different and more significant than those found in tree-ring widths. Preliminary results will be presented and discussed at EGU for the first time.

  9. Hydrologic effects on diameter growth phenology for Celtis laevigata and Quercus lyrata in the floodplain of the lower White River, Arkansas

    Science.gov (United States)

    Allen, Scott T.; Cochran, Wesley; Krauss, Ken W.; Keim, Richard F.; King, Sammy L.; Schweitzer, Callie Jo; Clatterbuck, Wayne K.; Oswalt, Christopher M.

    2016-01-01

    Bottomland hardwood (BLH) forests represent an extensive wetland system in the Mississippi Alluvial Valley and southeastern USA, and it is currently undergoing widespread transition in species composition. One such transition involves increased establishment of sugarberry (Celtis laevigata), and decreased establishment of overcup oak (Quercus lyrata). The ecological mechanisms that control this transition are not well understood. We measured monthly diameter growth with dendrometer bands on 86 sugarberry and 42 overcup oak trees at eight sites in the floodplain of the White River (AR, USA) with differing hydrologic regimes. For both species, growth attenuated earlier at drier sites compared to wetter sites. Overcup oak grew slightly longer through late August, suggesting its growth period extends across both wet and dry periods. In contrast, sugarberry growth rate decreased substantially by mid-July. While these results did not necessarily indicate a mechanism for increased prominence of sugarberry, they suggest sugarberry growing season does not as much coincide with the typically drier period of late summer and may be less affected by these conditions. Overcup oak grows later into the dry season and water table conditions during this period may determine if overcup oak benefits from this relatively extended growth period.

  10. Morphological and physiological divergences within Quercus ilex support the existence of different ecotypes depending on climatic dryness.

    Science.gov (United States)

    Peguero-Pina, José Javier; Sancho-Knapik, Domingo; Barrón, Eduardo; Camarero, Julio Jesús; Vilagrosa, Alberto; Gil-Pelegrín, Eustaquio

    2014-08-01

    Several studies show apparently contradictory findings about the functional convergence within the Mediterranean woody flora. In this context, this study evaluates the variability of functional traits within holm oak (Quercus ilex) to elucidate whether provenances corresponding to different morphotypes represent different ecotypes locally adapted to the prevaling stress levels. Several morphological and physiological traits were measured at leaf and shoot levels in 9-year-old seedlings of seven Q. ilex provenances including all recognized morphotypes. Plants were grown in a common garden for 9 years under the same environmental conditions to avoid possible biases due to site-specific characteristics. Leaf morphometry clearly separates holm oak provenances into 'ilex' (more elongated leaves with low vein density) and 'rotundifolia' (short and rounded leaves with high vein density) morphotypes. Moreover, these morphotypes represent two consistent and very contrasting functional types in response to dry climates, mainly in terms of leaf area, major vein density, leaf specific conductivity, resistance to drought-induced cavitation and turgor loss point. The 'ilex' and 'rotundifolia' morphotypes correspond to different ecotypes as inferred from their contrasting functional traits. To the best of our knowledge, this is the first time that the combined use of morphological and physiological traits has provided support for the concept of these two holm oak morphotypes being regarded as two different species. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

    Directory of Open Access Journals (Sweden)

    Grygoruk Dorota

    2016-06-01

    Full Text Available The main task of the present study was to investigate the root vitality of common beech Fagus sylvatica L., sessile oak Quercus petraea Liebl. and sycamore maple Acer pseudoplatanus L. in the optimal g rowth conditions in south-western Poland. The study was carried out in 130-year-old mixed stand located within natural range of studied tree species. The density of roots (g/100 cm3 of soil and biomass of fine roots (g/m2 in topsoil layers (0-5 cm, 5-15 cm were determined in the tree biogroups of the same species. The mean total root density ranged from 0.248 to 0.417 g/100 cm3 in the 0-5 cm soil layer, and it decreased in the deeper soil layer (5-15 cm. There were found no statistically significant differences of total root densities between tree biogroups in topsoil layers. Diversity of fine root biomass was comparable in the tree biogroups (H’ = 1.5, but common beech showed more intensive growth of fine roots in the topsoil 0-15 cm when compared to sessile oak and sycamore maple. The results of the study point out the stability of the multi-species structure of the mixed stand studied, and consequently - the ability of beech, sessile oak and sycamore maple trees to coexist in the mixed stands - in the area of natural range of these species.

  12. Síntesis del Encuentro Internacional sobre Ecología y Manejo de bosques de Quercus bajo una perspectiva de cambio global

    OpenAIRE

    Pérez-Ramos, Ignacio Manuel; Villar Montero, Rafael; Marañón, Teodoro

    2013-01-01

    Entre los días 30 de Septiembre y 2 de Octubre de 2013 tuvo lugar en Baeza (Jaén) un encuentro Internacional titulado “Oak forests coping with Global Change: ecology and management”, donde se trataron diversos aspectos relacionados con la filogeografía, genética, demografía, ecofisiología, vulnerabilidad, gestión y conservación de las especies de Quercus frente al Cambio Global. El encuentro estuvo financiado por la Universidad Internacional de Andalucía (UNIA), que se hi...

  13. Poison ivy - oak - sumac

    Science.gov (United States)

    ... ingredient can be found in: Bruised roots, stems, flowers, leaves, fruit Pollen of poison ivy , poison oak, ... further instructions. This is a free and confidential service. All local poison control centers in the United ...

  14. Decline in holm oak coppices (Quercus ilex L. subsp. ballota (Desf. Samp.: biometric and physiological interpretations

    Directory of Open Access Journals (Sweden)

    Rafael Serrada

    2017-10-01

    Research highlights: The above-ground physiological and morphological characteristics of declined stools are interpreted as poorer adaptation to site conditions. Root system architecture was found to be relevant to explain this behaviour.

  15. Differetial degradation of oak (Quercus petraea) leaf litter by litter-decomposing basidiomycetes

    Czech Academy of Sciences Publication Activity Database

    Steffen, K. T.; Cajthaml, Tomáš; Šnajdr, Jaroslav; Baldrian, Petr

    2007-01-01

    Roč. 158, č. 5 (2007), s. 447-455 ISSN 0923-2508 R&D Projects: GA ČR GA526/05/0168; GA MŠk LC06066 Institutional research plan: CEZ:AV0Z50200510 Keywords : biopolymers * carbohydrate * laccase Subject RIV: EE - Microbiology, Virology Impact factor: 2.219, year: 2007

  16. Predicting internal red oak (Quercus rubra) log defect features using surface defect defect measurements

    Science.gov (United States)

    R. Edward. Thomas

    2013-01-01

    Determining the defects located within a log is crucial to understanding the tree/log resource for efficient processing. However, existing means of doing this non-destructively requires the use of expensive x-ray/CT (computerized tomography), MRI (magnetic resonance imaging), or microwave technology. These methods do not lend themselves to fast, efficient, and cost-...

  17. Predicting internal white oak (Quercus alba) log defect features using surface defect indicator measurements

    Science.gov (United States)

    Ralph E. Thomas

    2012-01-01

    As hardwood trees grow and develop, surface defects such as limb stubs and wounds are overgrown and encapsulated into the tree. Evidence of these defects can remain on the tree's surface for decades and in many instances for the life of the tree. The location and severity of internal defects dictate the quality and value of products that can be obtained from logs...

  18. An experimental evaluation of fire history reconstruction using dendrochronology in white oak (Quercus alba)

    Science.gov (United States)

    Ryan W. McEwan; Todd F. Hutchinson; Robert D. Ford; Brian C. McCarthy

    2007-01-01

    Dendrochronological analysis of fire scars on tree cross sections has been critically important for understanding historical fire regimes and has influenced forest management practices. Despite its value as a tool for understanding historical ecosystems, tree-ring-based fire history reconstruction has rarely been experimentally evaluated. To examine the efficacy of...

  19. TOLERANCIA AL FUEGO EN Quercus magnoliifolia1

    Directory of Open Access Journals (Sweden)

    Miguel Ángel López Moctezuma

    2015-06-01

    Full Text Available RESUMENCon el objetivo de conocer la respuesta de Quercus magnoliifolia al fuego en mortalidad y rebrotación, se aplicó una quema prescrita intensa, en fajas a favor de viento y pendiente, a una parcela de 0.5 ha en el estado de Guerrero, México, en abril de 2009. La quema inició a las 10:20 y duró 1 h 26 min. Se midieron las variables meteorológicas temperatura (25-28 °C, humedad relativa (33-24%, y velocidad del viento (7-25 km/h; y de comportamiento del fuego (largo de llama, de 0.5 a 3 m.Seis meses después se midieron variables de la estructura del arbolado y de severidad de la quema. El análisis de datos involucró regresión logarítmica y regresión logística. Los valores estructurales medios fueron: altura (11.2 m, diámetro normal (12. 2 cm y altura de copas (6.8 m. Se halló relación logarítmica directa entre el largo de llama y la velocidad del viento (R2=0.65. No hubo mortalidad producto de la quema, pero 33 % de los árboles rebrotaron. Las variables explicativas de la probabilidad de rebrotación fueron: altura (p=0.0159, diámetro normal (p=0.0394y altura a la base de copas (p=0.0487. La cicatriz sobre el tronco alcanzó 2.6 m y el chamuscado de copas 62 %, en promedio. La especie muestra resistencia a fuego poco severo, gracias a su corteza, y tolerancia a fuego más severo. Las quemas prescritas contribuirían a reducir impactos negativos de incendios en el arbolado.

  20. Blue gods, blue oil, and blue people.

    Science.gov (United States)

    Fairbanks, V F

    1994-09-01

    Studies of the composition of coal tar, which began in Prussia in 1834, profoundly affected the economies of Germany, Great Britain, India, and the rest of the world, as well as medicine and surgery. Such effects include the collapse of the profits of the British indigo monopoly, the growth in economic power of Germany based on coal tar chemistry, and an economic crisis in India that led to more humane tax laws and, ultimately, the independence of India and the end of the British Empire. Additional consequences were the development of antiseptic surgery and the synthesis of a wide variety of useful drugs that have eradicated infections and alleviated pain. Many of these drugs, particularly the commonly used analgesics, sulfonamides, sulfones, and local anesthetics, are derivatives of aniline, originally called "blue oil" or "kyanol." Some of these aniline derivatives, however, have also caused aplastic anemia, agranulocytosis, and methemoglobinemia (that is, "blue people"). Exposure to aniline drugs, particularly when two or three aniline drugs are taken concurrently, seems to be the commonest cause of methemoglobinemia today.

  1. Water-use strategies in two co-occurring Mediterranean evergreen oaks: surviving the summer drought.

    Science.gov (United States)

    David, T S; Henriques, M O; Kurz-Besson, C; Nunes, J; Valente, F; Vaz, M; Pereira, J S; Siegwolf, R; Chaves, M M; Gazarini, L C; David, J S

    2007-06-01

    In the Mediterranean evergreen oak woodlands of southern Portugal, the main tree species are Quercus ilex ssp. rotundifolia Lam. (holm oak) and Quercus suber L. (cork oak). We studied a savannah-type woodland where these species coexist, with the aim of better understanding the mechanisms of tree adaptation to seasonal drought. In both species, seasonal variations in transpiration and predawn leaf water potential showed a maximum in spring followed by a decline through the rainless summer and a recovery with autumn rainfall. Although the observed decrease in predawn leaf water potential in summer indicates soil water depletion, trees maintained transpiration rates above 0.7 mm day(-1) during the summer drought. By that time, more than 70% of the transpired water was being taken from groundwater sources. The daily fluctuations in soil water content suggest that some root uptake of groundwater was mediated through the upper soil layers by hydraulic lift. During the dry season, Q. ilex maintained higher predawn leaf water potentials, canopy conductances and transpiration rates than Q. suber. The higher water status of Q. ilex was likely associated with their deeper root systems compared with Q. suber. Whole-tree hydraulic conductance and minimum midday leaf water potential were lower in Q. ilex, indicating that Q. ilex was more tolerant to drought than Q. suber. Overall, Q. ilex seemed to have more effective drought avoidance and drought tolerance mechanisms than Q. suber.

  2. Management of oak forests

    DEFF Research Database (Denmark)

    Löf, Magnus; Brunet, Jörg; Filyushkina, Anna

    2016-01-01

    Identification of the ecosystem services provided by oak-dominated forests in southern Sweden is a prerequisite for ensuring their conservation and sustainable management. These forests seem well-suited for multiple-use forestry, but knowledge is limited regarding how to manage them for multiple...... uses. Management for the production of high-value timber species like oaks and management to conserve biodiversity, or for cultural services can be in conflict with each other. This study evaluates the capacity of three contrasting management regimes to provide societies with economic revenue from...... timber production, habitats for biodiversity and cultural services, and the study analyses associated trade-offs and synergies. The three regimes were: intensive oak timber production (A), combined management for both timber production and biodiversity (B) and biodiversity conservation without management...

  3. Seasonal changes in carbon and nitrogen compound concentrations in a Quercus petraea chronosequence.

    Science.gov (United States)

    Gilson, Angélique; Barthes, Laure; Delpierre, Nicolas; Dufrêne, Éric; Fresneau, Chantal; Bazot, Stéphane

    2014-07-01

    Forest productivity declines with tree age. This decline may be due to changes in metabolic functions, resource availability and/or changes in resource allocation (between growth, reproduction and storage) with tree age. Carbon and nitrogen remobilization/storage processes are key to tree growth and survival. However, studies of the effects of tree age on these processes are scarce and have not yet considered seasonal carbon and nitrogen variations in situ. This study was carried out in a chronosequence of sessile oak (Quercus petraea Liebl.) for 1 year to survey the effects of tree age on the seasonal changes of carbon and nitrogen compounds in several tree compartments, focusing on key phenological stages. Our results highlight a general pattern of carbon and nitrogen function at all tree ages, with carbon reserve remobilization at budburst for growth, followed by carbon reserve formation during the leafy season and carbon reserve use during winter for maintenance. The variation in concentrations of nitrogen compounds shows less amplitude than that of carbon compounds. Storage as proteins occurs later, and mainly depends on leaf nitrogen remobilization and root uptake in autumn. We highlight several differences between tree age groups, in particular the loss of carbon storage function of fine and medium-sized roots with tree ageing. Moreover, the pattern of carbon compound accumulation in branches supports the hypothesis of a preferential allocation of carbon towards growth until the end of wood formation in juvenile trees, at the expense of the replenishment of carbon stores, while mature trees start allocating carbon to storage right after budburst. Our results demonstrate that at key phenological stages, physiological and developmental functions differ with tree age, and together with environmental conditions, influence the carbon and nitrogen concentration variations in sessile oaks. © The Author 2014. Published by Oxford University Press. All rights

  4. The historical significance of oak

    Science.gov (United States)

    J. V. Thirgood

    1971-01-01

    A brief history of the importance of oak in Europe, contrasting the methods used in France and Britain to propagate the species and manage the forests for continued productivity. The significance of oak as a strategic resource during the sailing-ship era is stressed, and mention is made of the early development of oak management in North America. The international...

  5. Countervailing effects on pine and oak leaf litter decomposition in human-altered Mediterranean ecosystems.

    Science.gov (United States)

    Sheffer, Efrat; Canham, Charles D; Kigel, Jaime; Perevolotsky, Avi

    2015-04-01

    Species affect the dynamics of litter decay through the intrinsic properties of their litter, but also by influencing the environmental conditions imposed by their canopy, roots, and litter layers. We examined how human-induced changes in the relative abundances of two dominant Mediterranean trees-Pinus halepensis and Quercus calliprinos-impact leaf litter decomposition. A reciprocal transplant experiment tested decomposition of pine, oak, and mixed leaf litter in oak woodland and pine forest ecosystems with different relative abundances of pine and oak. Using likelihood methods, we tested the importance and magnitude of the environmental effects of local species abundance, litter layer composition, and soil properties on litter mass loss. Oak litter decomposition was slower than pine, and had an antagonistic effect on mixed litter decay. These results differ from other reported pine-oak associations, and are probably associated with a higher content of tannins and phenols in oak compared to pine litter in our study sites. The environmental effects of the two species were opposite to their litter decomposition dynamics. An increased proportion of pine in the oak woodlands and a higher content of pine needles in the litter layer of pine forests reduced decay rates. The presence of more oak and broadleaf litter in the litter layer accelerated decomposition in pine forests. Our results highlight the importance of considering multidimensional species effects mediated by both chemical and physical properties, and imply that man-made changes in the composition and configuration of plant communities may result in complex unpredicted consequences to ecosystem biogeochemistry.

  6. Phytosociological studies of the forests with sessile oak and Norway spruce from South-Eastern Transylvania

    Directory of Open Access Journals (Sweden)

    Adrian Indreica

    2011-02-01

    Full Text Available The forests with sessile oak (Quercus petraea and Norway spruce (Picea abies from south-eastern Transylvania represent a peculiar type of phytocenoses, rather unusual for the present-day vegetation of Romania’s territory. Aim of the study is to provide a detailed description of the vegetation and to identify the phytosociological and typological units to which it could belong. Beside this, stand structure and regeneration status of the main tree species are illustrated. The studied area is located around Carpathian intermountain depressions Braşov and Ciuc, where vegetation had a peculiar history and today sessile oak forests on high altitude exists, interfering with spruce forests. The hypothesis of the process naturalness is supported by vegetation history in the area, climate, stand structure and peculiarities of herb layer composition (the mixture of relic of both mountain-boreal origin and south-European origin, like Vaccinium vitis-idaea, Pyrola rotundifolia and respectively Potentilla micrantha, Lathyrus venetus respectively. Sintaxonomically, studied phytocenoses with sessile oak and spruce belong mainly to acidophilus oak forests (Luzulo luzuloidis-Quercetum petraeae, but some of them resemble oak-hornbeam forests (Carici pilosae-Carpinetum, indicating a more recent change in stand structure and suggesting that not the soil, but the climate is the driving force of succession. Regeneration of sessile oak is at least satisfactory, but the expansion of spruce in such stands could seriously restrict the survival of sessile oak. A new typological unit will be appropriate,for a better management of sessile oak forests with spruce admixture.

  7. Phytosociological studies of the forests with sessile oak and Norway spruce from South-Eastern Transylvania

    Directory of Open Access Journals (Sweden)

    Adrian Indreica

    2011-06-01

    Full Text Available The forests with sessile oak (Quercus petraea and Norway spruce (Picea abies from south-eastern Transylvania represent a peculiar type of phytocenoses, rather unusual for the present-day vegetation of Romania’s territory. Aim of the study is to provide a detailed description of the vegetation and to identify the phytosociological and typological units to which it could belong. Beside this, stand structure and regeneration status of the main tree species are illustrated. The studied area is located around Carpathian intermountain depressions Brasov and Ciuc, where vegetation had a peculiar history and today sessile oak forests on high altitude exists, interfering with spruce forests. The hypothesis of the process naturalness is supported by vegetation history in the area, climate, stand structure and peculiarities of herb layer composition (the mixture of relic of both mountain-boreal origin and south-European origin, like Vaccinium vitis-idaea, Pyrola rotundifolia and respectively Potentilla micrantha, Lathyrus venetus respectively. Sintaxonomically, studied phytocenoses with sessile oak and spruce belong mainly to acidophilus oak forests (Luzulo luzuloidis-Quercetum petraeae, but some of them resemble oak-hornbeam forests (Carici pilosae-Carpinetum, indicating a more recent change in stand structure and suggesting that not the soil, but the climate is the driving force of succession. Regeneration of sessile oak is at least satisfactory, but the expansion of spruce in such stands could seriously restrict the survival of sessile oak. A new typological unit will be appropriate, for a better management of sessile oak forests with spruce admixture.

  8. Production of anticandidal cotton textiles treated with oak gall extract.

    Science.gov (United States)

    Tayel, Ahmed A; El-Tras, Wael F; Abdel-Monem, Omnia A; El-Sabbagh, Sabha M; Alsohim, Abdullah S; El-Refai, Elham M

    2013-01-01

    Candida albicans, one of the most dreadful fungal pathogens threatening humans, could not be easily prevented. The anticandidal activity of oak gall extract, Quercus infectoria (QIE), was investigated as a potential natural alternative to synthetic and chemical fungicides. QIE anticandidal potentiality was confirmed using both qualitative and quantitative assays. Cotton textiles were treated with QIE and then evaluated as anticandidal fabrics. QIE-treated textiles had a potent anticandidal activity, which could completely inhibit the inoculated C. albicans cells. The durability of anticandidal activity in QIE-treated textiles almost completely disappeared after the fourth laundering cycle. QIE could be recommended, however, as a potent anticandidal agent for preparing antiseptic solutions and emulsions and as a finishing agent for manufacturing anticandidal disposable diapers and hygienic clothes. Copyright © 2013 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  9. Production of anticandidal cotton textiles treated with oak gall extract

    Directory of Open Access Journals (Sweden)

    Ahmed A. Tayel

    Full Text Available Candida albicans, one of the most dreadful fungal pathogens threatening humans, could not be easily prevented. The anticandidal activity of oak gall extract, Quercus infectoria (QIE, was investigated as a potential natural alternative to synthetic and chemical fungicides. QIE anticandidal potentiality was confirmed using both qualitative and quantitative assays. Cotton textiles were treated with QIE and then evaluated as anticandidal fabrics. QIE-treated textiles had a potent anticandidal activity, which could completely inhibit the inoculated C. albicans cells. The durability of anticandidal activity in QIE-treated textiles almost completely disappeared after the fourth laundering cycle. QIE could be recommended, however, as a potent anticandidal agent for preparing antiseptic solutions and emulsions and as a finishing agent for manufacturing anticandidal disposable diapers and hygienic clothes.

  10. Heavy metal adsorption by modified oak sawdust: Thermodynamics and kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Argun, Mehmet Emin [Department of Environmental Engineering, Engineering and Architecture Faculty, Selcuk University, 42031 Selcuklu-Konya (Turkey)]. E-mail: argun@selcuk.edu.tr; Dursun, Sukru [Department of Environmental Engineering, Engineering and Architecture Faculty, Selcuk University, 42031 Selcuklu-Konya (Turkey); Ozdemir, Celalettin [Department of Environmental Engineering, Engineering and Architecture Faculty, Selcuk University, 42031 Selcuklu-Konya (Turkey); Karatas, Mustafa [Department of Environmental Engineering, Engineering and Architecture Faculty, Selcuk University, 42031 Selcuklu-Konya (Turkey)

    2007-03-06

    This paper describes the adsorption of heavy metal ions from aqueous solutions by oak (Quercus coccifera) sawdust modified by means of HCl treatment. Our study tested the removal of three heavy metals: Cu, Ni, and Cr. The optimum shaking speed, adsorbent mass, contact time, and pH were determined, and adsorption isotherms were obtained using concentrations of the metal ions ranging from 0.1 to 100 mg L{sup -1}. The adsorption process follows pseudo-second-order reaction kinetics, as well as Langmuir and D-R adsorption isotherms. The paper discusses the thermodynamic parameters of the adsorption (the Gibbs free energy, entropy, and enthalpy). Our results demonstrate that the adsorption process was spontaneous and endothermic under natural conditions. The maximum removal efficiencies were 93% for Cu(II) at pH 4, 82% for Ni(II) at pH 8, and 84% for Cr(VI) at pH 3.

  11. Land Change in Eastern Mediterranean Wood-Pasture Landscapes: The Case of Deciduous Oak Woodlands in Lesvos (Greece)

    Science.gov (United States)

    Schaich, Harald; Kizos, Thanasis; Schneider, Stefan; Plieninger, Tobias

    2015-07-01

    In Mediterranean Europe, wood-pasture landscapes with oak woodlands as emblematic ecosystems are undergoing rapid land-use change, which may threaten their legacy as hotspots of biodiversity, ecosystem services, and cultural heritage. The objective of this study was to quantify land cover changes and transitions as well as the dynamics of oak woodland patterns and densities over 50 years in two municipalities at the center and edges of Quercus macrolepis distribution in Northern Lesvos (Greece). We used aerial photographs from 1960 and WorldView-2 satellite images from 2010 to process land cover maps and metrics, and to calculate oak canopy cover with a point-grid sampling approach. Spatiotemporal dynamics of land cover change were generally high—especially between oak woodlands and grass- and shrub-lands, resulting in a more heterogeneous and fragmented landscape in 2010. Surprisingly, oak woodland area remained stable with marginal losses in one study site and gains in the other one. Oak canopy cover increased by 8 and 9 %. Spatial hotspots of change were mountainous and peripheral phrygana areas with expanding oak stands, as well as river valleys and near urban areas with expanding olive groves and grass- and shrublands in former complex cultivation and oak stands. We conclude that the parallel processes of abandonment of crop cultivation and intensification of livestock grazing have been less detrimental to oak woodlands than supposed. To ensure long-term persistence of oak woodlands in the face of ongoing rural depopulation and land-use intensification, environmental and agricultural policies should better address their specificities as anthropogenic habitats.

  12. Land change in eastern Mediterranean wood-pasture landscapes: the case of deciduous oak woodlands in Lesvos (Greece).

    Science.gov (United States)

    Schaich, Harald; Kizos, Thanasis; Schneider, Stefan; Plieninger, Tobias

    2015-07-01

    In Mediterranean Europe, wood-pasture landscapes with oak woodlands as emblematic ecosystems are undergoing rapid land-use change, which may threaten their legacy as hotspots of biodiversity, ecosystem services, and cultural heritage. The objective of this study was to quantify land cover changes and transitions as well as the dynamics of oak woodland patterns and densities over 50 years in two municipalities at the center and edges of Quercus macrolepis distribution in Northern Lesvos (Greece). We used aerial photographs from 1960 and WorldView-2 satellite images from 2010 to process land cover maps and metrics, and to calculate oak canopy cover with a point-grid sampling approach. Spatiotemporal dynamics of land cover change were generally high--especially between oak woodlands and grass- and shrub-lands, resulting in a more heterogeneous and fragmented landscape in 2010. Surprisingly, oak woodland area remained stable with marginal losses in one study site and gains in the other one. Oak canopy cover increased by 8 and 9%. Spatial hotspots of change were mountainous and peripheral phrygana areas with expanding oak stands, as well as river valleys and near urban areas with expanding olive groves and grass- and shrublands in former complex cultivation and oak stands. We conclude that the parallel processes of abandonment of crop cultivation and intensification of livestock grazing have been less detrimental to oak woodlands than supposed. To ensure long-term persistence of oak woodlands in the face of ongoing rural depopulation and land-use intensification, environmental and agricultural policies should better address their specificities as anthropogenic habitats.

  13. Effects of Mechanical Site Preparation on Growth of Oaks Planted on Former Agricultural Fields

    Directory of Open Access Journals (Sweden)

    John D. Hodges

    2011-12-01

    Full Text Available Mechanical site preparation is frequently proposed to alleviate problematic soil conditions when afforesting retired agricultural fields. Without management of soil problems, any seedlings planted in these areas may exhibit poor growth and survival. While mechanical site preparation methods currently employed in hardwood afforestation are proven, there is a substantial void in research comparing subsoiling, bedding, and combination plowing treatments. A total of 4,320 bare-root Nuttall oak (Quercus texana Buckley, Shumard oak (Quercus shumardii Buckley, and swamp chestnut oak (Quercus michauxii Nutt. seedlings were planted in February 2008 on three Mississippi sites. All sites were of comparable soils and received above average precipitation throughout the three-year duration of the study. Four site preparation treatments were replicated at each site, with 480 seedlings planted in each of nine replications, and a total of 1,440 seedlings per species planted across all sites. Mechanical treatments were installed using 3.1 m row centers, with treatments as follows: control, subsoiling, bedding, and combination plowing. Treatment effects on seedling height, groundline diameter (GLD, and survival were analyzed. Seedlings exhibited greater height in bedded and combination plowed areas (79.7 cm to 102.7 cm and 82.6 cm to 100.1 cm, respectively compared to subsoiled or control areas (70.4 cm to 84.6 cm and 71.4 cm to 86.9 cm, respectively. Greater GLD was observed in bedded and combination plowed areas (11.9 mm to 18.4 mm and 12.2 mm to 18.3 mm, respectively compared to subsoiled or control areas (10.2 mm to 14.6 mm and 10.5 mm to 15.6 mm, respectively. Survival was high for this study (94.%, and no differences were detected among treatments.

  14. variability in foliar phenolic composition of several quercus species in northern mexico

    International Nuclear Information System (INIS)

    Salazar, J.A.A.; Antuna, E.M.; Abarca, N.A.; Alvarado, E.A.D.

    2015-01-01

    Quantitative and qualitative composition of the foliar phenolic compounds were investigated in 81 individual specimens of several white oak species (Quercus spp.). The trees were growing in twelve locations in Durango, Mexico. The phenol profiles were determined by HPLC-DAD and a Folin-Ciocateuprocedure. The results revealed that: (i) the foliar phenol profiles of all species analysed were complex and formed by 6 to 30 compounds, (ii) the flavonols mostly quercetin glycoside, isorhamnetin glycoside, kaempferol glycoside and phenolic acids were the main identified compounds, (iii) there was a high intra and inter-specific variability in the foliar phenol profiles both at the quantitative and qualitative levels, and (iv) the foliar phenol profiles indicated a slight species-specific tendency for phenols to be accumulated, although this was not clearly distinguished. Significant differences (P < 0.05) in the content and composition of the foliar flavonoids between species were observed due to the large environmental and soil conditions variability between localities. (author)

  15. Taxonomic and Functional Diversity of a Quercus pyrenaica Willd. Rhizospheric Microbiome in the Mediterranean Mountains

    Directory of Open Access Journals (Sweden)

    José F. Cobo-Díaz

    2017-10-01

    Full Text Available Altitude significantly affects vegetation growth and distribution, including the developmental stages of a forest. We used shotgun Illumina sequencing to analyze microbial community composition and functional potential in melojo-oak (Quercus pyrenaica Willd. rhizospheric soil for three different development stages along an altitudinal gradient: (a a low altitude, non-optimal site for forest maintenance; (b an intermediate altitude, optimal site for a forest; and (c a high altitude, expansion site with isolated trees but without a real forest canopy. We observed that, at each altitude, the same microbial taxa appear both in the taxonomic analysis of the whole metagenome and in the functional analysis of the methane, sulfur and nitrogen metabolisms. Although there were no major differences at the functional level, there were significant differences in the abundance of each taxon at the phylogenetic level between the rhizospheres of the forest (low and intermediate altitudes and the expansion site. Proteobacteria and Actinobacteria were the most differentially abundant phyla in forest soils compared to the expansion site rhizosphere. Moreover, Verrucomicrobia, Bacteroidetes and Nitrospirae phyla were more highly represented in the non-forest rhizosphere. Our study suggests that rhizospheric microbial communities of the same tree species may be affected by development stage and forest canopy cover via changes in soil pH and the C/N ratio.

  16. Foliage nitrogen turnover: differences among nitrogen absorbed at different times by Quercus serrata saplings

    Science.gov (United States)

    Ueda, Miki U.; Mizumachi, Eri; Tokuchi, Naoko

    2011-01-01

    Background and Aims Nitrogen turnover within plants has been intensively studied to better understand nitrogen use strategies. However, differences among the nitrogen absorbed at different times are not completely understood and the fate of nitrogen absorbed during winter is largely uncharacterized. In the present study, nitrogen absorbed at different times of the year (growing season, winter and previous growing season) was traced, and the within-leaf nitrogen turnover of a temperate deciduous oak Quercus serrata was investigated. Methods The contributions of nitrogen absorbed at the three different times to leaf construction, translocation during the growing season, and the leaf-level resorption efficiency during leaf senescence were compared using 15N. Key Results Winter- and previous growing season-absorbed nitrogen significantly contributed to leaf construction, although the contribution was smaller than that of growing season-absorbed nitrogen. On the other hand, the leaf-level resorption efficiency of winter- and previous growing season-absorbed nitrogen was higher than that of growing season-absorbed nitrogen, suggesting that older nitrogen is better retained in leaves than recently absorbed nitrogen. Conclusions The results demonstrate that nitrogen turnover in leaves varies with nitrogen absorption times. These findings are important for understanding plant nitrogen use strategies and nitrogen cycles in forest ecosystems. PMID:21515608

  17. Genetic stability evaluation of quercus suber l. somatic embryogenesis by rapd analysis

    International Nuclear Information System (INIS)

    Fernandes, P.; Costa, A.; Rocha, A.C.C.; Santos, C.

    2011-01-01

    A reliable protocol for adult Quercus suber L. somatic embryogenesis (SE) was developed recently. To evaluate the potential use of this protocol in cork oak forest breeding programs, it is essential to guarantee somatic embryos/emblings genetic stability. Random Amplification of Polymorphic DNA (RAPD) is currently used to assess somaclonal variation providing information on genetic variability of the micropropagation process. In this work, SE was induced from adult trees by growing leaf explants on MS medium supplemented with 2,4-D and zeatin. Embling conversion took place on MS medium without growth regulators. DNA from donor tree, somatic embryos and emblings was used to assess genetic variability by RAPD fingerprinting. Fourteen primers produced 165 genetic loci with high quality and reproducibility. Despite somatic embryos originated some poor quality PCR-profiles, replicable and excellent fingerprints were obtained for both donor plant and embling. Results presented no differences among regenerated emblings and donor plant. Hence, the SE protocol used did not induce, up to moment, any genetic variability, confirming data previously obtained with other molecular/genetic techniques, supporting that this protocol may be used to provide true-to-type plants from important forestry species. (author)

  18. Bud burst and flowering phenology in a mixed oak forest from Eastern Romania

    Directory of Open Access Journals (Sweden)

    Ecaterina Nicoleta Chesnoiu

    2009-12-01

    Full Text Available Bud burst and flowering phenology have been observed in year 2008 in a natural white oak species complex situated in eastern Romania. A total of 300 mature individuals was mapped and identified based on leaf morphology. The community consists of four oak species: Quercus pedunculiflora, Q. robur, Q. pubescens and Q. petraea. A set of 28 individuals could not be unambiguously classified to one or another species. Data on bud burst showed a normal distribution and the differences among species were small. The "very late" flushing was recorded on 15th of April, three weeks later when compared to early flushing individuals. The time period between the bud burst and the complete development of leaves was nearly the same in all oak species, varying on average, between 18.4 and 20.6 days. The spatial distribution of phenological groups within the complex appears to be non-randomly, because in many parts of the study plot exist groups in which most of the trees belong to the same phenological category. Our results indicate an overlap in flowering time for all oak species which occur in the area. The data support the hypothesis that interspecific gene flow is possible between closely related oak species.

  19. Bud burst and flowering phenology in a mixed oak forest from Eastern Romania

    Directory of Open Access Journals (Sweden)

    Ecaterina Nicoleta Chesnoiu

    2009-11-01

    Full Text Available Bud burst and flowering phenology have been observed in year 2008 ina natural white oak species complex situated in eastern Romania. A total of 300 mature individuals was mapped and identified based on leaf morphology. The community consists of four oak species: Quercus pedunculiflora, Q. robur, Q. pubescens and Q. petraea. A set of 28 individuals could not be unambiguously classified to one or another species. Data on bud burst showed a normal distribution and the differences among species were small. The "very late" flushing was recorded on 15th of April, three weeks later when compared to early flushing individuals. The time period between the bud burst and the complete development of leaves was nearly the same in all oak species, varying on average, between 18.4 and 20.6 days. The spatialdistribution of phenological groups within the complex appears to be non-randomly, because in many parts of the study plot exist groups in which most of the trees belong to the same phenological category. Our results indicate an overlap in flowering time for all oak species which occur in the area. The data support the hypothesis that interspecific gene flow is possible between closely related oak species.

  20. Why sustain oak forests?

    Science.gov (United States)

    David Wm. Smith

    2006-01-01

    A brief overview and some personal thoughts are offered that deal with the implications of our social and political systems on the long-term sustainability of our forest resources. The connection of the most recent climatic events, in a geologic-time context, to the development of present day oak dominated forests of the Eastern United States is discussed. The impacts...

  1. Short communicationi: Shelled acorn seed ( Quercus cerris ) as a ...

    African Journals Online (AJOL)

    This study was carried out to investigate the effects of dietary inclusion of shelled acorn seed (Quercus cerris) on the growth performance and carcass yield of Japanese quail (Coturnix coturnix japonica). Four hundred four-day old quail chicks were used in this study. Experimental diets contained 0, 5, 10, 15 or 20% shelled ...

  2. Posthuman blues

    CERN Document Server

    Tonnies, Mac

    2013-01-01

    Posthuman Blues, Vol. I is first volume of the edited version of the popular weblog maintained by author Mac Tonnies from 2003 until his tragic death in 2009. Tonnies' blog was a pastiche of his original fiction, reflections on his day-to-day life, trenchant observations of current events, and thoughts on an eclectic range of material he culled from the Internet. What resulted was a remarkably broad portrait of a thoughtful man and the complex times in which he lived, rendered with intellige...

  3. Dendrochronological Investigations of Valonia Oak Trees in Western Greece

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    Andreas Papadopoulos

    2016-06-01

    Full Text Available Background and Purpose: Valonia oak (Quercus ithaburensis subsp. macrolepis (Kotschy Hedge & Yalt. is an east Mediterranean endemic, xerothermic and deciduous tree of particular interest in forestry. There has been a growing demand lately to include the species in reforestations in Greece which also increased the interest to investigate its response to climate change. The main purpose of this research is to study valonia oak from a dendrochronological – dendroclimatological point of view within its Mediterranean distribution range. Materials and Methods: Sampling took place in characteristic valonia oak stands where cross sections or tree-cores were taken from 40 trees. The cross sections and the tree-cores were prepared and cross-dated using standard dendrochronological methods and tree-ring widths were measured to the nearest 0.001 mm using the Windendro software program. The ARSTAN program was used to standardize the tree-ring data and to calculate dendrochronological statistical parameters. The inter-annual variability of tree-ring width and the radial growth trend were examined. Finally, tree-ring widths to climate relationships were calculated by orthogonal regression in combination with the bootstrap procedure using master residual chronology and monthly precipitation, temperature data and scPDSI drought index, from October of the n-1 year up to November of the n year. Results: The master chronology of valonia oak trees in Western Greece reaches 365 years, with an average ring width of 0.89 mm and with mean sensitivity being 0.21. The variation of the tree-ring widths indicates the influence of climate and human intervention in the past. Tree-ring to climate relationships show that valonia oak growth is positively affected by precipitations in January and March and by drought reduction during June and July. Conclusions: Valonia oak in Western Greece is a species of great interest for dendrochronological and dendroclimatological studies

  4. Genetic Structure and Evolutionary History of Three Alpine Sclerophyllous Oaks in East Himalaya-Hengduan Mountains and Adjacent Regions.

    Science.gov (United States)

    Feng, Li; Zheng, Qi-Jian; Qian, Zeng-Qiang; Yang, Jia; Zhang, Yan-Ping; Li, Zhong-Hu; Zhao, Gui-Fang

    2016-01-01

    The East Himalaya-Hengduan Mountains (EH-HM) region has a high biodiversity and harbors numerous endemic alpine plants. This is probably the result of combined orographic and climate oscillations occurring since late Tertiary. Here, we determined the genetic structure and evolutionary history of alpine oak species (including Quercus spinosa, Quercus aquifolioides , and Quercus rehderiana ) using both cytoplasmic-nuclear markers and ecological niche models (ENMs), and elucidated the impacts of climate oscillations and environmental heterogeneity on their population demography. Our results indicate there were mixed genetic structure and asymmetric contemporary gene flow within them. The ENMs revealed a similar demographic history for the three species expanded their ranges from the last interglacial (LIG) to the last glacial maximum (LGM), which was consistent with effective population sizes changes. Effects of genetic drift and fragmentation of habitats were responsible for the high differentiation and the lack of phylogeographic structure. Our results support that geological and climatic factors since Miocene triggered the differentiation, evolutionary origin and range shifts of the three oak species in the studied area and also emphasize that a multidisciplinary approach combining molecular markers, ENMs and population genetics can yield deep insights into diversification and evolutionary dynamics of species.

  5. Observations on natural regeneration in grazed Holm oak stands in the Ogliastra province (Sardinia, Italy

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    Sioni S

    2011-07-01

    Full Text Available This paper deals with the effects of grazing pressure in two Holm oak (Quercus ilex stands in Ogliastra (central-eastern Sardinia, Italy, with particular reference to the interactions with the natural regeneration processes. There is a positive interaction (facilitation between shrubs and seedlings of tree species, as observed in other similar studies carried out by the same authors in other areas of Sardinia. Rubus ulmifolius proved to be the most efficient shrub for the protection and growth of saplings; the other shrub species play a less marked facilitating role. Although the density of shrubs hosting Holm oak seedlings is fairly high, their age and small size confirm that the current grazing pressure is incompatible with any chance of growth of the saplings and success of the natural regeneration. The conservation of these stands must therefore rely on the rationalisation of human activities through the exploitation of a whole range of resources.

  6. Oak mortality associated with crown dieback and oak borer attack in the Ozark Highlands

    Science.gov (United States)

    Zhaofei Fan; John M. Kabrick; Martin A. Spetich; Stephen R. Shifley; Randy G. Jensen

    2008-01-01

    Oak decline and related mortality have periodically plagued upland oak–hickory forests, particularly oak species in the red oak group, across the Ozark Highlands of Missouri, Arkansas and Oklahoma since the late 1970s. Advanced tree age and periodic drought, as well as Armillaria root fungi and oak borer attack are believed to contribute to oak decline and mortality....

  7. Soil CO2 Efflux in a Mixed Pine-Oak Forest in Valsaín (Central Spain

    Directory of Open Access Journals (Sweden)

    Rosa Inclán

    2007-01-01

    Full Text Available Soil-surface CO2 efflux and its spatial and temporal variation were investigated in a southern Mediterranean, mixed pine-oak forest ecosystem on the northern slopes of the Sierra de Guadarrama in Spain from February 2006 to July 2006. Measurements of soil CO2 efflux, soil temperatures, and moisture were conducted in nine 1963-m2 sampling plots distributed in a gradient around the ecotone between Pinus sylvestris L. and Quercus pyrenaica Lam. forest stands. Total soil organic matter, Walkey-Black C, particulate organic matter, organic matter fraction below 53 μm, total soil nitrogen content, total soil organic carbon content, and pH were also measured under three representative mature oak, pine, and mixed pine-oak forest stands. Soil respiration showed a typical seasonal pattern with minimums in winter and summer, and maximums in spring, more pronounced in oak and oak-pine stands. Soil respiration values were highest in pine stands during winter and in oak stands during spring and summer.

  8. Analýza druhové diverzity mikromycet ve fyloplánu dubu letního Quercus robur infikovaného padlí dubovým Erysiphe alphitoides pomocí klasických a molekulárních metod

    OpenAIRE

    MICHÁLEK, Jan

    2009-01-01

    This bibliographical search review includes an overview of present results of research on phylloplane fungi, their biology, ecology and impact on environment particularly the possible effect on the occurrence and parasitism of oak powdery mildew (Erysiphe alphitoides) on the leaves of Quercus robur. The special focus is aimed at the methods of isolation and identification of phylloplane fungi in environmental samples by using classical and modern molecular methods.

  9. Approaches to restoration of oak forests on farmed lowlands of the Mississippi river and its tributaries (Avances en la restauración de bosques de roble en tierras bajas agrícolas del Río Mississippi y sus tributaries)

    Science.gov (United States)

    E.S. Gardiner; D.C. Dey; John Stanturf; B.R. Lockhart

    2010-01-01

    The lowlands associated with the Mississippi River and its tributaries historically supported extensive broadleaf forests that were particularly rich in oak (Quercus spp.) species. Beginning in the 1700s, deforestation for agriculture substantially reduced the extent of the original forest, and fragmented the remainder into small parcels. More recently, declines in...

  10. Morphological Response of Eight Quercus Species to Simulated Wind Load.

    Science.gov (United States)

    Wu, Tonggui; Zhang, Peng; Zhang, Lei; Wang, Geoff G; Yu, Mukui

    Leaf shape, including leaf size, leaf dissection index (LDI), and venation distribution, strongly impacts leaf physiology and the forces of momentum exerted on leaves or the canopy under windy conditions. Yet, little has been known about how leaf shape affects the morphological response of trees to wind load. We studied eight Quercus species, with different leaf shapes, to determine the morphological response to simulated wind load. Quercus trees with long elliptical leaves, were significantly affected by wind load (Pwind load, such as bigger leaf thickness, larger stem diameter, allocation to root biomass, and smaller stem height (Pwind can reduce drag and increase the mechanical strength of the tree. Leaf dissection index (LDI), an important index of leaf shape, was correlated with morphological response to wind load (Pwind load.

  11. Association of genetic and phenotypic variability with geography and climate in three southern California oaks.

    Science.gov (United States)

    Riordan, Erin C; Gugger, Paul F; Ortego, Joaquín; Smith, Carrie; Gaddis, Keith; Thompson, Pam; Sork, Victoria L

    2016-01-01

    Geography and climate shape the distribution of organisms, their genotypes, and their phenotypes. To understand historical and future evolutionary and ecological responses to climate, we compared the association of geography and climate of three oak species (Quercus engelmannii, Quercus berberidifolia, and Quercus cornelius-mulleri) in an environmentally heterogeneous region of southern California at three organizational levels: regional species distributions, genetic variation, and phenotypic variation. We identified climatic variables influencing regional distribution patterns using species distribution models (SDMs), and then tested whether those individual variables are important in shaping genetic (microsatellite) and phenotypic (leaf morphology) variation. We estimated the relative contributions of geography and climate using multivariate redundancy analyses (RDA) with variance partitioning. The modeled distribution of each species was influenced by climate differently. Our analysis of genetic variation using RDA identified small but significant associations between genetic variation with climate and geography in Q. engelmannii and Q. cornelius-mulleri, but not in Q. berberidifolia, and climate explained more of the variation. Our analysis of phenotypic variation in Q. engelmannii indicated that climate had more impact than geography, but not in Q. berberidifolia. Throughout our analyses, we did not find a consistent pattern in effects of individual climatic variables. Our comparative analysis illustrates that climate influences tree response at all organizational levels, but the important climate factors vary depending on the level and on the species. Because of these species-specific and level-specific responses, today's sympatric species are unlikely to have similar distributions in the future. © 2016 Botanical Society of America.

  12. Impacts of human-induced environmental disturbances on hybridization between two ecologically differentiated Californian oak species.

    Science.gov (United States)

    Ortego, Joaquín; Gugger, Paul F; Sork, Victoria L

    2017-01-01

    Natural hybridization, which can be involved in local adaptation and in speciation processes, has been linked to different sources of anthropogenic disturbance. Here, we use genotypic data to study range-wide patterns of genetic admixture between the serpentine-soil specialist leather oak (Quercus durata) and the widespread Californian scrub oak (Quercus berberidifolia). First, we estimated hybridization rates and the direction of gene flow. Second, we tested the hypothesis that genetic admixture increases with different sources of environmental disturbance, namely anthropogenic destruction of natural habitats and wildfire frequency estimated from long-term records of fire occurrence. Our analyses indicate considerable rates of hybridization (> 25%), asymmetric gene flow from Q. durata into Q. berberidifolia, and a higher occurrence of hybrids in areas where both species live in close parapatry. In accordance with the environmental disturbance hypothesis, we found that genetic admixture increases with wildfire frequency, but we did not find a significant effect of other sources of human-induced habitat alteration (urbanization, land clearing for agriculture) or a suite of ecological factors (climate, elevation, soil type). Our findings highlight that wildfires constitute an important source of environmental disturbance, promoting hybridization between two ecologically well-differentiated native species. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  13. Community composition of root-associated fungi in a Quercus-dominated temperate forest: “codominance” of mycorrhizal and root-endophytic fungi

    Science.gov (United States)

    Toju, Hirokazu; Yamamoto, Satoshi; Sato, Hirotoshi; Tanabe, Akifumi S; Gilbert, Gregory S; Kadowaki, Kohmei

    2013-01-01

    In terrestrial ecosystems, plant roots are colonized by various clades of mycorrhizal and endophytic fungi. Focused on the root systems of an oak-dominated temperate forest in Japan, we used 454 pyrosequencing to explore how phylogenetically diverse fungi constitute an ecological community of multiple ecotypes. In total, 345 operational taxonomic units (OTUs) of fungi were found from 159 terminal-root samples from 12 plant species occurring in the forest. Due to the dominance of an oak species (Quercus serrata), diverse ectomycorrhizal clades such as Russula, Lactarius, Cortinarius, Tomentella, Amanita, Boletus, and Cenococcum were observed. Unexpectedly, the root-associated fungal community was dominated by root-endophytic ascomycetes in Helotiales, Chaetothyriales, and Rhytismatales. Overall, 55.3% of root samples were colonized by both the commonly observed ascomycetes and ectomycorrhizal fungi; 75.0% of the root samples of the dominant Q. serrata were so cocolonized. Overall, this study revealed that root-associated fungal communities of oak-dominated temperate forests were dominated not only by ectomycorrhizal fungi but also by diverse root endophytes and that potential ecological interactions between the two ecotypes may be important to understand the complex assembly processes of belowground fungal communities. PMID:23762515

  14. Restoring sand shinnery oak prairies with herbicide and grazing in New Mexico

    Science.gov (United States)

    Zavaleta, Jennifer C.; Haukos, David A.; Grisham, Blake A.; Boal, Clint W.; Dixon, Charles

    2016-01-01

    Sand shinnery oak (Quercus havardii) prairies are increasingly disappearing and increasingly degraded in the Southern High Plains of Texas and New Mexico. Restoring and managing sand shinnery oak prairie can support biodiversity, specific species of conservation concern, and livestock production. We measured vegetation response to four treatment combinations of herbicide (tebuthiuron applied at 0.60 kg/ha) and moderate-intensity grazing (50% removal of annual herbaceous production) over a 10-year period in a sand shinnery oak prairie of eastern New Mexico. We compared the annual vegetation response to the historical climax plant community (HCPC) as outlined by the U.S. Department of Agriculture Ecological Site Description. From 2 to 10 years postapplication, tebuthiuron-treated plots had reduced shrub cover with twice as much forb and grass cover as untreated plots. Tebuthiuron-treated plots, regardless of the presence of grazing, most frequently met HCPC. Tebuthiuron and moderate-intensity grazing increased vegetation heterogeneity and, based on comparison of the HCPC, successfully restored sand shinnery oak prairie to a vegetation composition similar to presettlement.

  15. Use of an airborne lidar system to model plant species composition and diversity of Mediterranean oak forests.

    Science.gov (United States)

    Simonson, William D; Allen, Harriet D; Coomes, David A

    2012-10-01

    Airborne lidar is a remote-sensing tool of increasing importance in ecological and conservation research due to its ability to characterize three-dimensional vegetation structure. If different aspects of plant species diversity and composition can be related to vegetation structure, landscape-level assessments of plant communities may be possible. We examined this possibility for Mediterranean oak forests in southern Portugal, which are rich in biological diversity but also threatened. We compared data from a discrete, first-and-last return lidar data set collected for 31 plots of cork oak (Quercus suber) and Algerian oak (Quercus canariensis) forest with field data to test whether lidar can be used to predict the vertical structure of vegetation, diversity of plant species, and community type. Lidar- and field-measured structural data were significantly correlated (up to r= 0.85). Diversity of forest species was significantly associated with lidar-measured vegetation height (R(2) = 0.50, p lidar data. Lidar can be applied widely for mapping of habitat and assessments of habitat condition (e.g., in support of the European Species and Habitats Directive [92/43/EEC]). However, particular attention needs to be paid to issues of survey design: density of lidar points and geospatial accuracy of ground-truthing and its timing relative to acquisition of lidar data. ©2012 Society for Conservation Biology.

  16. BVOC emission pattern from Quercus robur under field conditions

    Science.gov (United States)

    Pokorska, O.; Dewulf, J.; Joó; Šimpraga, M.; Steppe, K.; Amelynck, C.; Schoon, N.; Muller, J. J.; van Langenhove, H.

    2010-12-01

    Over the past decades biogenic volatile organic compounds (BVOC) have been widely studied not only for better understanding their functions, biosynthesis and regulation, but also because they have great impact on regional and global air quality [1]. Since all BVOCs react with hydroxyl radicals (OH●) and may also react with nitrate radicals (NO3●) and ozone (O3), they contribute to the formation of ozone and secondary organic aerosols. In this study we focus on Quercus robur which is a widely spread tree species in Europe and known as a strong isoprene emitter. We aimed to investigate seasonal patterns of BVOC emissions from Quercus robur under field conditions and to explore the intra-species variations within Quercus robur trees as both are of great importance for accurate modeling and regional inventories. Measurements were performed during a period from May till October 2009 at the campus of Ghent University (Belgium) using a dynamic branch enclosure system. Experiments were conducted on four potted Quercus robur trees with a varying 1-1.5 m height. Samples were collected on Tenax TA-Carbotrap adsorbent tubes and analyzed by TD-GC-MS. Isoprene was the predominant compound released by Quercus robur (QR1) with a pronounced seasonal emission. The normalized emission rates for isoprene calculated according to Guenther’s algorithm (standard conditions of temperature 30°C and PAR 1000 µmol m-2 s-1) varied from 29.89 µg h-1 g(DW)-1 in Spring (May) to 28.62 µg h-1 g(DW)-1 in Fall (October) reaching peak of 105.51 µg h-1 g(DW)-1 in August. Apart from isoprene, through the whole measurement period trans-β-ocimene and β-caryophyllene were the only BVOC emitted in detectable range (sum of the emissions varied between 0.15 µg h-1 g(DW)-1 in July and 0.24 µg h-1 g(DW)-1 in October). No clear seasonal pattern was observed for those compounds. In May when acorns where developing on enclosed branch, emissions of limonene and β-farnesene were also observed. The

  17. RNA-seq analysis of Quercus pubescens Leaves: de novo transcriptome assembly, annotation and functional markers development.

    Directory of Open Access Journals (Sweden)

    Sara Torre

    Full Text Available Quercus pubescens Willd., a species distributed from Spain to southwest Asia, ranks high for drought tolerance among European oaks. Q. pubescens performs a role of outstanding significance in most Mediterranean forest ecosystems, but few mechanistic studies have been conducted to explore its response to environmental constrains, due to the lack of genomic resources. In our study, we performed a deep transcriptomic sequencing in Q. pubescens leaves, including de novo assembly, functional annotation and the identification of new molecular markers. Our results are a pre-requisite for undertaking molecular functional studies, and may give support in population and association genetic studies. 254,265,700 clean reads were generated by the Illumina HiSeq 2000 platform, with an average length of 98 bp. De novo assembly, using CLC Genomics, produced 96,006 contigs, having a mean length of 618 bp. Sequence similarity analyses against seven public databases (Uniprot, NR, RefSeq and KOGs at NCBI, Pfam, InterPro and KEGG resulted in 83,065 transcripts annotated with gene descriptions, conserved protein domains, or gene ontology terms. These annotations and local BLAST allowed identify genes specifically associated with mechanisms of drought avoidance. Finally, 14,202 microsatellite markers and 18,425 single nucleotide polymorphisms (SNPs were, in silico, discovered in assembled and annotated sequences. We completed a successful global analysis of the Q. pubescens leaf transcriptome using RNA-seq. The assembled and annotated sequences together with newly discovered molecular markers provide genomic information for functional genomic studies in Q. pubescens, with special emphasis to response mechanisms to severe constrain of the Mediterranean climate. Our tools enable comparative genomics studies on other Quercus species taking advantage of large intra-specific ecophysiological differences.

  18. [Effects of simulating acid rain on photosynthesis and chlorophyll fluorescence parameters of Quercus glauca Quercus glauca].

    Science.gov (United States)

    Wang, Sai; Yi, Li-Ta; Yu, Shu-Quan; Zhang, Chao; Shi, Jing-Jing

    2014-08-01

    At three levels of simulated acid rainfall intensities with pH values of 2.5 (severe), 40 (medium) and 5.6 (light) respectively, the responses of chlorophyll fluorescence and photosynthetic parameters of Quercus glauca seedlings were studied in three acid rainfall treatments, i. e. only the aboveground of seedlings exposed to acid rain (T1), both of the seedlings and soil exposed to acid rain (T2), only the soil exposed to acid rain (T3) compared with blank control (CK). Under the severe acid rainfall, T1 significantly inhibited chlorophyll synthesis, and thus reduced the primary photochemical efficiency of PS II ( F(v)/F(m)), potential activity of PS II (F(v)/F(o)) , apparent quantum (Y), net photosynthetic rate (P(n)), and transpiration rate (T(r)), but increased the light compensation point (LCP) and dark respiration rate (R(d)) of Q. glauca seedlings. T2 inhibited, but T3 played a little enhancement on the aforementioned parameters of Q. glauca seedlings. Under the conditions of medium and light acid rainfall intensities, the above parameters in the three treatments were higher than that of CK, except with lower R(d). The chlorophyll fluorescence and photosynthetic parameters showed a similar tendency in the three treatments, i. e. T2>T3 >T1. It indicated that T1 had the strongest inhibition on seedlings in condition of the severe acid rainfall, while T2 had the most dramatic facilitating effect on seedlings under the medium and light acid rainfall. Intensity of acid rainfall had significant influences on SPAD, F(v)/F(m), F(v)/F(o), Y, P(n), T(r), and maximum photosynthetic rate (A(max)), whereas treatments of acid rainfall affected SPAD, F(v)/F(m), Y, P(n), T(r), A(max) and light saturation point (LSP). The interaction of acid rainfall intensities and treatments played significant effects on SPAD, F(v)/F(m), Y, P(n) and A(max).

  19. Effects of declining oak vitality on ecosystem functions: Lessons from a Spanish oak woodland

    Science.gov (United States)

    López-Sánchez, Aida; Bareth, Georg; Bolten, Andreas; Linstädter, Anja

    2017-04-01

    Mediterranean oak woodlands have a great ecological and socio-economic importance. Today, these fragile ecosystems are facing unprecedented degradation threats from Novel Oak Diseases (NODs). Among NOD drivers, maladapted land management practices and climate change are most important. Although it is generally believed that NOD-related declines in tree vitality will have detrimental effects on ecosystem functions, little is known on the magnitude of change, and whether different functions are affected in a similar way. Here we analyzed effects of tree vitality on various ecosystem functions, comparing subcanopy and intercanopy habitats across two oak species (Quercus ilex and Q. suber) in a Spanish oak woodland. We asked how functions - including aboveground net primary productivity (ANPP), taxonomic diversity, and litter decomposition rates - were affected by oak trees' size and vitality. We also combined measurements in the ecosystem function habitat index (MEFHI), a proxy of ecosystem multifunctionality. Field research was carried out in 2016 on a dehesa in southern Spain. We used a stratified random sampling to contrast trees of different species affiliation, size and vitality. Tree vitality was estimated as crown density (assessed via hemispherical photography), and as tree vigor, which combines the grade of canopy defoliation with proxies for tree size (dbh, height, crown height and crown radius). For each tree (n = 34), two plots (50 x 50 cm) were located; one in the subcanopy habitat, and the other in the intercanopy area beyond the tree crown's influence. On all 68 plots, moveable cages were placed during the main growth period (March to May) to estimate ANPP under grazed conditions. Litter decomposition rates were assessed via the tea bag index. ANPP and the biomass of grasses, forbs and legumes were recorded via destructive sampling. To take plots' highly variable environmental conditions into account, we recorded a suite of abiotic and biotic

  20. The Role of Tree Mortality in Vitality Assessment of Sessile Oak Forests

    Directory of Open Access Journals (Sweden)

    Imre Berki

    2016-12-01

    Full Text Available Background and Purpose: The drought-induced vitality loss of sessile oak (Quercus petraea (Matt. Liebl. has been continuously observed in Hungary for more than three decades. The decrease in stand density as a consequence of drought-induced mortality has not been taken into consideration in most of the monitoring methods. Materials and Methods: Forest stands without any forest intervention during the last 30 years were selected. Quadrats were designated for the analysis in 18 sessile oak stands along a climatic transect in which foliage transparency and stand density were measured. Drought stress was defined by the water balance approach. By combining the foliage transparency and the relative stand density, a new cumulative assessment method of stand level vitality was introduced to get a more realistic picture about the effects of long-term drought (lasting for several decades on the sessile oak forests in South-East Europe. Results: The calculated health status (100% - vital; 0% - dead of the sessile oak stands was between 70-90% in the moist South-West Hungary and below 50% close to its xeric limit. The individual tree-based vitality assessment method gave considerably higher values on 17 out of 18 sites. Conclusions: Forest monitoring should also consider stand level-based tree mortality in oak forests while assessing health condition especially close to its xeric limit. The proposed new method provides a more realistic picture about the effects of climate change on sessile oak stands particularly for forest managers interested in changing in the wood stock of forests.

  1. The changes of the forests dendroproduction in the Carpathian basin - case study: Quercus petraea

    Science.gov (United States)

    Berki, Imre; Gulyás, Krisztina; Veperdi, Gábor

    2017-04-01

    There are a lot of publications about the accelerated forest growth in West-and North- Europe due to global climate change, elevated atmospheric carbon-dioxide and nitrogen input. However, in Central-Europe the increasing tendency of extremely dry periods caused mass mortality of forest formed tree species, and triggered slower or indefinite growth trends. In this study our scientific questions were the followings: • Which are the characteristic mechanism in the south-east part of Central -Europe: forest decay, accelerated growth or both? • What are the expected impacts of climate change on sessile oak production? • Are there any differences between a humid and an arid landscapes tree height growth? Method for measuring the changes of growth in humid landscapes: Top height of the stands is a good indicator of the site condition with high stand density. So this indicator can be used to measure the changes of growth in humid stands, where the drought periods caused not considerable tree decay. We have been measured a young and old sessile oak stands next to each other along a humid-arid climatic transect in Hungary. The old stands representing the "pre-climate change" conditions, when the annual temperature means, and the frequency of droughts were lower. The young stands have been lived their whole lifetime in changed atmospheric condition. Compared the top height of the young and old stand to the yield tables we can establish a soft accelerated growth in the last decades in the humid landscapes. Method for measuring the changes of growth in dry landscapes: Top height of thinned forests due to tree decay do not indicate the changed atmospheric condition. Although the volume of the survived trees has been increased (compared to yield tables) due to accelerated diameter growth, the production of the thinned Quercus petraea forests have been decreased. Keywords: tree height growth, nitrogen input, humid-arid climatic transect Acknowledgements: Research is

  2. Adaptive and plastic responses of Quercus petraea populations to climate across Europe.

    Science.gov (United States)

    Sáenz-Romero, Cuauhtémoc; Lamy, Jean-Baptiste; Ducousso, Alexis; Musch, Brigitte; Ehrenmann, François; Delzon, Sylvain; Cavers, Stephen; Chałupka, Władysław; Dağdaş, Said; Hansen, Jon Kehlet; Lee, Steve J; Liesebach, Mirko; Rau, Hans-Martin; Psomas, Achilleas; Schneck, Volker; Steiner, Wilfried; Zimmermann, Niklaus E; Kremer, Antoine

    2017-07-01

    How temperate forests will respond to climate change is uncertain; projections range from severe decline to increased growth. We conducted field tests of sessile oak (Quercus petraea), a widespread keystone European forest tree species, including more than 150 000 trees sourced from 116 geographically diverse populations. The tests were planted on 23 field sites in six European countries, in order to expose them to a wide range of climates, including sites reflecting future warmer and drier climates. By assessing tree height and survival, our objectives were twofold: (i) to identify the source of differential population responses to climate (genetic differentiation due to past divergent climatic selection vs. plastic responses to ongoing climate change) and (ii) to explore which climatic variables (temperature or precipitation) trigger the population responses. Tree growth and survival were modeled for contemporary climate and then projected using data from four regional climate models for years 2071-2100, using two greenhouse gas concentration trajectory scenarios each. Overall, results indicated a moderate response of tree height and survival to climate variation, with changes in dryness (either annual or during the growing season) explaining the major part of the response. While, on average, populations exhibited local adaptation, there was significant clinal population differentiation for height growth with winter temperature at the site of origin. The most moderate climate model (HIRHAM5-EC; rcp4.5) predicted minor decreases in height and survival, while the most extreme model (CCLM4-GEM2-ES; rcp8.5) predicted large decreases in survival and growth for southern and southeastern edge populations (Hungary and Turkey). Other nonmarginal populations with continental climates were predicted to be severely and negatively affected (Bercé, France), while populations at the contemporary northern limit (colder and humid maritime regions; Denmark and Norway) will

  3. Ozone risk assessment in three oak species as affected by soil water availability.

    Science.gov (United States)

    Hoshika, Yasutomo; Moura, Barbara; Paoletti, Elena

    2018-03-01

    To derive ozone (O 3 ) dose-response relationships for three European oak species (Quercus ilex, Quercus pubescens, and Quercus robur) under a range of soil water availability, an experiment was carried out with 2-year-old potted seedlings exposed to three levels of water availability in the soil and three levels of O 3 pollution for one growing season in an ozone free-air controlled exposure (FACE) facility. Total biomass losses were estimated relative to a hypothetical clean air at the pre-industrial age, i.e., at 10 ppb as daily average (M24). A stomatal conductance model was parameterized with inputs from the three species for calculating the stomatal O 3 flux. Exposure-based (M24, W126, and AOT40) and flux-based (phytotoxic O 3 dose (POD) 0-3 ) dose-response relationships were estimated and critical levels (CL) were calculated for a 5% decline of total biomass. Results show that water availability can significantly affect O 3 risk assessment. In fact, dose-response relationships calculated per individual species at each water availability level resulted in very different CLs and best metrics. In a simplified approach where species were aggregated on the basis of their O 3 sensitivity, the best metric was POD 0.5 , with a CL of 6.8 mmol m -2 for the less O 3 -sensitive species Q. ilex and Q. pubescens and of 3.5 mmol m -2 for the more O 3 -sensitive species Q. robur. The performance of POD 0 , however, was very similar to that of POD 0.5 , and thus a CL of 6.9 mmol m -2 POD 0 and 3.6 mmol m -2 POD 0 for the less and more O 3 -sensitive oak species may be also recommended. These CLs can be applied to oak ecosystems at variable water availability in the soil. We conclude that POD y is able to reconcile the effects of O 3 and soil water availability on species-specific oak productivity.

  4. [Anaphylaxis to blue dyes].

    Science.gov (United States)

    Langner-Viviani, F; Chappuis, S; Bergmann, M M; Ribi, C

    2014-04-16

    In medicine, vital blue dyes are mainly used for the evaluation of sentinel lymph nodes in oncologic surgery. Perioperative anaphylaxis to blue dyes is a rare but significant complication. Allergic reactions to blue dyes are supposedly IgE-mediated and mainly caused by triarylmethanes (patent blue and isosulfane blue) and less frequently by methylene blue. These substances usually do not feature on the anesthesia record and should not be omitted from the list of suspects having caused the perioperative reaction, in the same manner as latex and chlorhexidine. The diagnosis of hypersensitivity to vital blue dyes can be established by skin test. We illustrate this topic with three clinical cases.

  5. Comparison of leaf water use efficiency of oak and sycamore in the canopy over two growing seasons

    OpenAIRE

    Stokes, Victoria J.; Morecroft, Michael D.; Morison, James I.L.

    2010-01-01

    The seasonal trends in water use efficiency of sun and shade leaves of mature oak (Quercus robur) and sycamore (Acer pseudoplatanus) trees were assessed in the upper canopy of an English woodland. Intrinsic water use efficiency (net CO2 assimilation rate/leaf conductance, A/g) was measured by gas exchange and inferred from C isotope discrimination (δ13C) methods. Shade leaves had consistently lower δ13C than sun leaves (by 1–2‰), the difference being larger in sycamore. Buds had distinct sun ...

  6. Management and Yield Prediction of Kunugi (Quercus acutissima) Grazing Forests

    OpenAIRE

    Mitsuo, Matsumoto; Kenjirou, Honda; Juuro, Kurogi; Forest Management Division, Forestry and Forest Products Research Institute; Formerly Kyushu Research Center, Forestry and Forest Products Research Institute; Formerly Kyushu Research Center, Forestry and Forest Products Research Institute

    1999-01-01

    This study deals with grazing in kunugi (Quercus acutissima) forests in the Aso district of Kyushu Island in southwest Japan. These forests are managed for production of bed-logs for shiitake mushrooms and cow-calf farming. One of their characteristics is short-term rotation such as 10-15 years for bed-logs and a year for calf production. A forest grazing experiment was begun in Minamioguni to look at forest growth, vegetation change and grazing intensity. Stem densities dropped in a few year...

  7. Catalytic Rapid Pyrolysis of Quercus variabilis over Nanoporous Catalysts

    OpenAIRE

    Hyeon Koo Kang; In-Gu Lee; Kyong-Hwan Lee; Beom-Sik Kim; Tae Su Jo; Kwang-Seok Chea; Sung Hoon Park; Sang-Chul Jung; Young-Kwon Park

    2015-01-01

    Catalytic rapid pyrolysis of Quercus variabilis, a Korean native tree species, was carried out using Py-GC/MS. Mesoporous MFI, which has both nanopores and micropores, and three nanoporous materials, Al-MCM-41, Al-SBA-15, and γ-Al2O3, were used as the catalyst. The acid sites of mesoporous MFI were strong Brønsted acid sites, whereas those of nanoporous materials were mostly weak acid sites. The composition of the product bio-oil varied greatly depending on the acid characteristics of the cat...

  8. Survival and growth of three endangered oak species in a Mexican montane cloud forest

    Directory of Open Access Journals (Sweden)

    Ofelia Andrea Valdés-Rodríguez

    2017-07-01

    Full Text Available Cloud forests are amongst the world’s most impacted and endangered forest types, with Mexican cloud forests amongst the most degraded. These species rich forests are characterized by a diversity of congeneric oak species which dominate the canopy of mature forests. An improved understanding of the establishment requirements of oak seedlings in cloud forests is needed for conservation and restoration purposes. The aim of this study was to assess the influence of light conditions during early establishment of three endangered Quercus species. Seedling growth and biomass allocation in Quercus insignis M. Martens & Galeotti, Q. sartorii Liebm. and Q. xalapensis Bonpl. was determined under two light levels: light gap (1338 µmol m-2 s-1 and closed canopy (118 µmol m-2 s-1 in a cloud forest in Veracruz, Mexico. Growth and development were evaluated over the first 13 months. Results suggest there was a significant effect of light conditions on growth rate and biomass allocation. Although survival rate was similar among both environments, the three species showed lower growth rates under the closed canopy during the first nine months, while elongation rate was higher during the last three months under this environment compared to the light gap. Across all species, fresh biomass and dry biomass of roots, stem and leaves were almost 50% higher in light gap than under closed canopy. Q. insignis produced more biomass in shoots and roots than Q. sartorii and Q. xalapensis, which may increase its establishment success in shaded conditions. Results suggest that these three oak species are suited to planting in small gaps, but also in shaded understory conditions, as high early survival (>90% may allow enrichment planting in advance of gap creation.

  9. The red oak - white oak forests of the Anthracite Region

    Science.gov (United States)

    C. F. Burnham; M. J. Ferree; F. E. Cunningham

    1947-01-01

    The red oak - white oak forests of the Anthracite Region occupy as substantial portion - 28.6 percent or 915,200 acres - of the region's 3,198,400 acres of forest land. These forests have been so heavily cut for lumber and mine timbers during the past 100 years and have been so badly ravaged by fire following these heavy cuttings that in their present condition...

  10. The Quercus feeding Stigmella species of the West Palaearctic: new species, key and distribution (Lepidoptera: Nepticulidae)

    NARCIS (Netherlands)

    Nieukerken, van E.J.; Johansson, R.

    2003-01-01

    The species of the Stigmella ruficapitella group occurring in the Western Palaearctic and feeding on Quercus are reviewed. We recognise 19 species, five of which are described as new: Stigmella fasciata sp. n. on Quercus pubescens from Slovenia, Croatia, Greece and Turkey, S. cocciferae sp. n. on Q.

  11. DYNAMIC OF TREE POPULATIONS AND HORIZONTAL STRUCTURE OF THE OLD-GROWTH NEMORAL HERB BROAD-LEAVED FOREST WITH DOMINATION OF QUERCUS ROBUR AND TILIA CORDATA (ACCORDING TO THE RESULTS OF LONG-TERM MONITORING, PENZA REGION

    Directory of Open Access Journals (Sweden)

    A. A. Chistyakova

    2017-12-01

    Full Text Available A forecast for the development of old-growth nemoral herb broad-leaved forest with domination of Quercus robur and Tilia cordata in the Inselsky forest range (the Penza region is given in the article. The community belongs to the association Mercurialo perrenis-Quercetum roboris Bulokhov et Solomeshch 2003 according the Braun-Blanquet floristic classification. Long-term monitoring observations (28 years on a permanent sample plot were the basis of the forecasts. The ontogenetic state of tree species coenopopulations was analyzed and maps were produced for placing biogroups of trees of different age. The study showed that the existing horizontal structure (mosaic of the studied community ensures the reliable development of only shade-tolerant species (Acer platanoides, Tilia cordata, Fraxinus excelsior, Ulmus glabra. The available light regime is not sufficient for development of light-demanding species (Quercus robur, Populus tremula. The small number of oak individuals in the population and the death of its undergrowth make the position of Quercus robur very vulnerable in modern communities. The incompleteness of tree species composition and the inability to restore it with the existing structure of the community make it possible to characterize the broad-leaved forest as a quasi-climax. The transformation of this forest into the climax is impossible without human intervention. Reducing size of mosaic prevents the formation of uneven-aged populations of all potential tree species in the future.

  12. Relative importance of various regeneration mechanisms in different restoration stages of Quercus variabilis forest after selective logging

    Directory of Open Access Journals (Sweden)

    Yaoqin Xue

    2014-08-01

    Full Text Available Aim of study: Quercus variabilis (Chinese cork oak reproduces asexually and sexually. This study aimed to determine the status and growth of asexual and sexual recruits of Q. variabilis in different forest recovery stages.Area of study: Three selective logged stands and one unlogged stand in Q. variabilis forest, Shaanxi Province, China.Material and Methods: Origin, number, basal diameter, height and size structure of Q. variabilis shoots (height ≤200 cm were investigated in the plots of 5, 10, and 20-years post-logging stands and unlogged stand. Effects of recovery stage on the density and growth of the three original recruits (stump sprouts, stem base sprouts and true seedlings were analysis by One-way ANOVA.Main results: Sprouts dominated logged stands, whereas true seedlings dominated unlogged stand, stem base sprouts only existed in 20-years post-logging and unlogged stands. Stump sprout density and sprout number per stump both declined with extended post-logging time. True seedlings density increased from 7 to 20 shoots/100 m2 as the postlogging time extended, and peaked in unlogged stand (94 shoots/100 m2. An ongoing size structure was observed in true seedlings in all stands. Stump sprouts were taller and greater than true seedlings.Research highlights: Stump sprouts contributed more to Q. variabilis forest recovery in the early stage after disturbance. The contribution of true seedlings was limited in the same stage, but they were beneficial for population long-term development. Stem base sprouts were most likely to be a survival strategy rather than a reproductive strategy.Key words: asexual reproduction; true seedling; post-logging time; Chinese cork oak.

  13. Species-specific Mechanisms Contributing to the Mesophication of Upland Oak Stands in the Absence of Fire

    Science.gov (United States)

    Babl, E. K.; Alexander, H. D.; Siegert, C. M.; Willis, J. L.; Berry, A. I.

    2017-12-01

    Upland oak forests of the eastern United States are shifting dominance towards shade-tolerant, fire-intolerant species. This shift is hypothesized to be driven by anthropogenic fire suppression and lead to mesophication, a positive feedback loop where shade-tolerant, fire-sensitive species (i.e. mesophytes) create a cool, moist understory, reducing forest flammability and promoting their own proliferation at the expense of pyrophytic, shade-intolerant species such as oaks. There have been few empirical studies identifying mechanisms of mesophication, and these studies have yet to extensively explore potential mesophytes other than red maple (Acer rubrum). To address this issue, we sampled four hypothesized mesophytes (A. rubrum, A. saccharum, Carya glabra, and Fagus grandifolia) and two upland oak species (Quercus alba and Q. montana) across a gradient of sizes (20-60 cm DBH) in western Kentucky. We quantified canopy, bark, and leaf litter traits among upland oaks and mesophytes that may lead to differences in forest flammability. Preliminary results show that mesophytes had thinner and smoother bark than upland oaks and an increased canopy volume (normalized to stem volume), traits known to influence water movement through the canopy and understory microclimate. Maple leaf litter also decomposed faster, which could decrease fuel loads; after 6 months, red and sugar maple leaf litter lost 37% of original mass compared to 32%, 22%, and 14% mass loss in hickory, oak, and American beech litter, respectively. Furthermore, volumetric soil moisture of the soil organic layer beneath the canopies of mesophytes was 62% moister two days following a rainfall event compared to oaks. These differences in soil organic layer water retention after rainfall could lead to fuel discontinuity. These findings suggest that mesophytes may alter future forest flammability through their bark, canopy, and leaf litter traits which may modify fuel moisture, loads, and continuity and that a

  14. Within-tree variation in transpiration in isolated evergreen oak trees: evidence in support of the pipe model theory.

    Science.gov (United States)

    Infante, J M; Mauchamp, A; Fernández-Alé, R; Joffre, R; Rambal, S

    2001-04-01

    Within-tree variation in sap flow density (SFD) was measured in two isolated evergreen oak (Quercus ilex L.) trees growing in an oak savannah (dehesa) in southwest Spain. Sap flow was estimated by the constant heating method. Three sensors were installed in the trunk of each tree in three orientations: northeast (NE), northwest (NW) and south (S). Sap flow density was monitored continuously from May 18 to September 27, 1993. Daily values of SFD ranged between 500 and 4500 mm3 mm-2 day-1. There were significant differences in SFD between orientations; SFD was higher in the NE and NW orientations than in the S orientation. These differences were noted on both a daily and seasonal time scale, and were less pronounced on cloudy days and at the end of the drought period, when SFD was relatively low. Our results support the idea that branches of trees can be viewed as a collection of small independent plants.

  15. Mid-term successional patterns after fire of mixed pine oak forests in NE Spain

    Science.gov (United States)

    Gracia, Marc; Retana, Javier; Roig, Pere

    2002-12-01

    This study analyzes the factors affecting the current variability in density and age and size structure of mixed pine-oak forests of Pinus nigra and Quercus faginea in Central Catalonia (NE Spain), 37 years after a wildfire. The objective is to determine whether different post-disturbance responses may be obtained from the same pre-fire community and which factors can determine these different potential responses. The two factors analyzed were the distance to the unburned forest and site conditions (represented in this case by different aspects). The response of pines and oaks was different to the pattern expected for the Mediterranean Basin. Oaks resprouted immediately from stools already present before the fire and dominated during the first years, independent of both disturbance and site conditions. Pines established later, and their response depended on both factors: pine density decreased sharply from the forest edge to the burned area, and the number of pines was also higher in the more mesic than in the more xeric conditions. The age structure analysis for pines and oaks in the different aspects also revealed site-dependent rates of succession manifested by initial differences in post-fire establishment. In mesic plots, the establishment of pines occurred quite early, while in xeric plots, pine recruitment was delayed several years. These different patterns of post-fire recovery have led to pine dominance in more mesic sites and codominance of pines and oaks in more xeric ones, suggesting that different mid-term post-fire patterns can be identified for the same pre-fire forest type, depending on variations in environmental conditions.

  16. Self-thinning dynamics in cork oak woodlands: providing a baseline for managing density

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, T.; Monteiro, L.; Enes, T.; Cerveira, A.

    2017-11-01

    Aim of study: The study aims to evaluate the maximum potential stocking level in cork oak (Quercus suber L.) woodlands, using the ecologically-based size-density relationship of the self-thinning law. Area of study: The study area refers to cork oak forests in mainland Portugal, distributed along its 18 districts from north to south. Material and Methods: A dataset with a total of 2181 observations regarding pure cork oak stands was collected from the Portuguese Forest Inventory (NFI) databases and from research plots. The dataset was subjected to two filtering procedures, one more restrictive than the other, to select the stands presenting the higher stocking values. The two resulting subsets, with 116 and 36 observations, from 16 and 10 districts of mainland Portugal, respectively, were then used to assess and describe the allometric relationship between tree number and their mean diameter. Main results: The allometric relationship was analysed and modelled using the log transformed variables. A slightly curvilinear trend was identified. Thus, a straight line and a curve were both fitted for comparison purposes. Goodness-of-fit statistics point out for a good performance when the data is set to the uppermost observed stocking values. A self-thinning line for cork oak was projected from the estimated relationship. Research highlights: The self-thinning model can be used as an ecological approach to develop density guidelines for oak woodlands in a scenario of increasing cork demands. The results indicate that the recommendations being applied in Portugal are far below the maximal potential stocking values for the species. It is therefore of the utmost importance to review the traditional silvicultural guidelines and endorse new ones.

  17. Blue cures blue but be cautious

    Directory of Open Access Journals (Sweden)

    Pranav Sikka

    2011-01-01

    Full Text Available Methemoglobinemia is a disorder characterized by the presence of >1% methemoglobin (metHb in the blood. Spontaneous formation of methemoglobin is normally counteracted by protective enzyme systems, for example, nicotinamide adenine dinucleotide phosphate (NADPH methemoglobin reductase. Methemoglobinemia is treated with supplemental oxygen and methylene blue (1-2 mg/kg administered slow intravenously, which acts by providing an artificial electron acceptor for NADPH methemoglobin reductase. But known or suspected glucose-6-phosphate dehydrogenase (G6PD deficiency is a relative contraindication to the use of methylene blue because G6PD is the key enzyme in the formation of NADPH through pentose phosphate pathway and G6PD-deficient individuals generate insufficient NADPH to efficiently reduce methylene blue to leukomethylene blue, which is necessary for the activation of the NADPH-dependent methemoglobin reductase system. So, we should be careful using methylene blue in methemoglobinemia patient before G6PD levels.

  18. Age trends and within-site effects in wood density and radial growth in Quercus faginea mature trees

    Directory of Open Access Journals (Sweden)

    Vicelina B. Sousa

    2016-04-01

    Full Text Available Aim of the study: This paper aims to valorize the wood of Quercus faginea Lam. for high quality end uses (e.g. furniture by studying growth and quality properties using mature trees. Age trends in tree-ring width and wood density are shown and the main factors responsible for variations in tree-ring width and wood density within and between trees are investigated. Area of study: The study site is in the center of Portugal within the natural species distribution area.Material and methods: Radial samples from ten mature trees were collected at 6 heights (from base to 9.7 m and prepared for X-ray microdensity.Main results: Wood density showed high values, ranging from 0.868 g/cm3 to 0.957 g/cm3. Wood density decreased from pith to bark and with stem height. Cambial age showed a linear relationship with wood density and most of the variation in wood is explained by age. Intra-ring and axial within-tree homogeneity was good.Research highlights: Mature trees of Q. faginea showed high wood density and a high potential for high quality end uses, comparable to other oaks. Wood density is influenced by cambial age and tree-ring width. Wood quality may be improved by tree growth rates adjustment e.g. through an adequate tree stand density (e.g. thinning operations. 

  19. Age trends and within-site effects in wood density and radial growth in Quercus faginea mature trees

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, V.B.; Louzada, J.L.; Pereira, H.

    2016-07-01

    Aim of study: This paper aims to valorize the wood of Quercus faginea Lam. for high quality end uses (e.g. furniture) by studying growth and quality properties using mature trees. Age trends in tree-ring width and wood density are shown and the main factors responsible for variations in tree-ring width and wood density within and between trees are investigated. Area of study: The study site is in the center of Portugal within the natural species distribution area. Material and methods: Radial samples from ten mature trees were collected at 6 heights (from base to 9.7 m) and prepared for X-ray microdensity. Main results: Wood density showed high values, ranging from 0.868 g/cm3 to 0.957 g/cm3. Wood density decreased from pith to bark and with stem height. Cambial age showed a linear relationship with wood density and most of the variation in wood is explained by age. Intra-ring and axial within-tree homogeneity was good. Research highlights: Mature trees of Q. faginea showed high wood density and a high potential for high quality end uses, comparable to other oaks. Wood density is influenced by cambial age and tree-ring width. Wood quality may be improved by tree growth rates adjustment e.g. through an adequate tree stand density (e.g. thinning operations). (Author)

  20. Paisang (Quercus griffithii): a keystone tree species in sustainable agroecosystem management and livelihoods in Arunachal Pradesh, India.

    Science.gov (United States)

    Singh, Ranjay K; Singh, Anshuman; Garnett, Stephen T; Zander, Kerstin K; Lobsang; Tsering, Darge

    2015-01-01

    In a study of the traditional livelihoods of 12 Monpa and Brokpa villages in Arunachal Pradesh, India using social-ecological and participatory rural appraisal techniques, we found that the forest tree species paisang (Quercus griffithii, a species of oak) is vital to agroecosystem sustainability. Paisang trees are conserved both by individuals and through community governance, because their leaves play a crucial role in sustaining 11 traditional cropping systems of the Monpa peoples. An Indigenous institution, Chhopa, regulates access to paisang leaves, ensuring that the relationship between paisang and traditional field crop species within Monpa agroecosystems is sustainable. The Monpa farmers also exchange leaves and agricultural products for yak-based foods produced by the transhumant Brokpa, who are primarily yak herders. Yak herds also graze in paisang groves during winter. These practices have enabled the conservation of about 33 landraces, yak breeds, and a number of wild plants. Paisang thus emerged as a culturally important keystone species in the cultures and livelihoods of both Monpa and Brokpa. Ecological and conservation knowledge and ethics about paisang vary with gender, social systems, and altitudes. Labor shortages, however, have already caused some changes to the ways in which paisang leaves are used and yak grazing patterns are also changing in the face of changes in attitude among local landowners. Given new competing interests, incentives schemes are now needed to conserve the ecologically sustainable traditional livelihoods.

  1. The effect of induced heat waves on Pinus taeda and Quercus rubra seedlings in ambient and elevated CO2 atmospheres.

    Science.gov (United States)

    Ameye, Maarten; Wertin, Timothy M; Bauweraerts, Ingvar; McGuire, Mary Anne; Teskey, Robert O; Steppe, Kathy

    2012-10-01

    Here, we investigated the effect of different heat-wave intensities applied at two atmospheric CO2 concentrations ([CO2]) on seedlings of two tree species, loblolly pine (Pinus taeda) and northern red oak (Quercus rubra). Seedlings were assigned to treatment combinations of two levels of [CO2] (380 or 700 μmol mol(-1)) and four levels of air temperature (ambient, ambient +3°C, or 7-d heat waves consisting of a biweekly +6°C heat wave, or a monthly +12°C heat wave). Treatments were maintained throughout the growing season, thus receiving equal heat sums. We measured gas exchange and fluorescence parameters before, during and after a mid-summer heat wave. The +12°C heat wave, significantly reduced net photosynthesis (Anet) in both species and [CO2] treatments but this effect was diminished in elevated [CO2]. The decrease in Anet was accompanied by a decrease in Fv'/Fm' in P. taeda and ΦPSII in Q. rubra. Our findings suggest that, if soil moisture is adequate, trees will experience negative effects in photosynthetic performance only with the occurrence of extreme heat waves. As elevated [CO2] diminished these negative effects, the future climate may not be as detrimental to plant communities as previously assumed. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  2. Paisang ( Quercus griffithii): A Keystone Tree Species in Sustainable Agroecosystem Management and Livelihoods in Arunachal Pradesh, India

    Science.gov (United States)

    Singh, Ranjay K.; Singh, Anshuman; Garnett, Stephen T.; Zander, Kerstin K.; Lobsang; Tsering, Darge

    2015-01-01

    In a study of the traditional livelihoods of 12 Monpa and Brokpa villages in Arunachal Pradesh, India using social-ecological and participatory rural appraisal techniques, we found that the forest tree species paisang ( Quercus griffithii, a species of oak) is vital to agroecosystem sustainability. Paisang trees are conserved both by individuals and through community governance, because their leaves play a crucial role in sustaining 11 traditional cropping systems of the Monpa peoples. An Indigenous institution, Chhopa, regulates access to paisang leaves, ensuring that the relationship between paisang and traditional field crop species within Monpa agroecosystems is sustainable. The Monpa farmers also exchange leaves and agricultural products for yak-based foods produced by the transhumant Brokpa, who are primarily yak herders. Yak herds also graze in paisang groves during winter. These practices have enabled the conservation of about 33 landraces, yak breeds, and a number of wild plants. Paisang thus emerged as a culturally important keystone species in the cultures and livelihoods of both Monpa and Brokpa. Ecological and conservation knowledge and ethics about paisang vary with gender, social systems, and altitudes. Labor shortages, however, have already caused some changes to the ways in which paisang leaves are used and yak grazing patterns are also changing in the face of changes in attitude among local landowners. Given new competing interests, incentives schemes are now needed to conserve the ecologically sustainable traditional livelihoods.

  3. Photosynthetic responses to elevated CO2 and O3 in Quercus ilex leaves at a natural CO2 spring

    International Nuclear Information System (INIS)

    Paoletti, E.; Seufert, G.; Della Rocca, G.; Thomsen, H.

    2007-01-01

    Photosynthetic stimulation and stomatal conductance (Gs) depression in Quercus ilex leaves at a CO 2 spring suggested no down-regulation. The insensitivity of Gs to a CO 2 increase (from ambient 1500 to 2000 μmol mol -1 ) suggested stomatal acclimation. Both responses are likely adaptations to the special environment of CO 2 springs. At the CO 2 -enriched site, not at the control site, photosynthesis decreased 9% in leaves exposed to 2x ambient O 3 concentrations in branch enclosures, compared to controls in charcoal-filtered air. The stomatal density reduction at high CO 2 was one-third lower than the concomitant Gs reduction, so that the O 3 uptake per single stoma was lower than at ambient CO 2 . No significant variation in monoterpene emission was measured. Higher trichome and mesophyll density were recorded at the CO 2 -enriched site, accounting for lower O 3 sensitivity. A long-term exposure to H 2 S, reflected by higher foliar S-content, and CO 2 might depress the antioxidant capacity of leaves close to the vent and increase their O 3 sensitivity. - Very high CO 2 concentrations did not compensate for the effects of O 3 on holm oak photosynthesis

  4. Morphological and functional diversity of foliar damage on Quercus mongolica Fisch. ex Ledeb. (Fagaceae by herbivorous insects and pathogenic fungi

    Directory of Open Access Journals (Sweden)

    Jae-Cheon Sohn

    2017-12-01

    Full Text Available Insect-feeding damage on plants provides insight into plant–insect interactions along environmental gradients. However, cataloging such damage has been limited for fossil flora or extant tropical vegetation. We explored the diversity of insect-feeding damage on Quercus mongolica; one of the major tree species in the East Asian temperate forests. Eighty-six types of damage were cataloged from five sites on three mountains in Korea. Each damage type identified from our study was compared to previously proposed types of damage. The possible or confirmed origin of each damage type was discussed. The diversity of the damage types was highest from Mt. Seongjusan, followed by Mt. Jirisan and Mt. Hallasan. The frequency of each damage type on the leaves varied among research sites. Damage involving sap-sucking arthropods and pathogenic fungi was most frequent and exhibited greater among-site variation among the eight functional categories. Keywords: Among-site variation, Foliar damage, Herbivory, Mongolian oaks, Plant–insect interactions

  5. Blue-Green Algae

    Science.gov (United States)

    ... people with hepatitis C or hepatitis B. HIV/AIDS. Research on the effects of blue-green algae in people with HIV/AIDS has been inconsistent. Some early research shows that taking 5 grams of blue-green ...

  6. Holocene semi-arid oak woodlands in the Irano-Anatolian region of Southwest Asia: natural or anthropogenic?

    Science.gov (United States)

    Asouti, Eleni; Kabukcu, Ceren

    2014-04-01

    It is commonly accepted that, following the end of the Pleistocene, semi-arid deciduous oak woodlands did not spread in the Irano-Anatolian region of Southwest Asia as quickly as they did in the Levantine Mediterranean littoral, despite the fact that climatic improvement occurred broadly at the same time in both regions. Prehistoric impacts on woodland vegetation (such as woodcutting, burning and clearance for cultivation), the harsh continental climate of inland Southwest Asia and its distance from late Pleistocene arboreal refugia have all been discussed in the literature as likely causes of the delay. In this paper we argue that semi-arid deciduous oak woodlands should not be viewed as part of the “natural” vegetation of the Irano-Anatolian region that has been progressively destroyed by millennia of human activities since the Neolithic. They represent instead one of the earliest anthropogenic vegetation types in Southwest Asia, one that owes its very existence to prehistoric landscape practices other scholars commonly label as “destructive”. Drawing on anthracological, pollen and modern vegetation data from central Anatolia we describe how the post-Pleistocene species-rich and structurally diverse temperate semi-arid savanna grasslands were gradually substituted by low-diversity, even-aged Quercus-dominated parklands and wood pastures in the course of the early Holocene. Economic strategies that encouraged the establishment and spread of deciduous oaks included sheep herding that impacted on grass and forb vegetation, the controlling of competing arboreal vegetation through woodcutting, and woodland management practices such as coppicing, pollarding and shredding that enhanced Quercus vegetative propagation, crown and stem growth. Understanding the origin and evolution of the Irano-Anatolian semi-arid oak woodlands of Southwest Asia is of critical importance for reconstructing the changing ecologies and geographical distributions of the progenitors of

  7. Evaluating small mammal response to natural disturbance and restoration in oak ecosystems in the Mississippi alluvial valley

    International Nuclear Information System (INIS)

    Smith Carl G; Hamel Paul B; Fuzaro Gullo, Manoelle

    2010-01-01

    Oak species form a conspicuous and often dominant component of bottom land forests of the Mississippi Alluvial Valley. The extent of these forests has been drastically reduced as a result of clearing for agriculture in the past two centuries. Patterns of clearing have reduced the distribution of remaining forest patches to a much more flood-prone subset of the landscape than was historically the case, reducing the diversity of oak species currently present on the landscape. Intensive harvesting has further changed the composition of the remaining stands. Small remnant patches of primary forest continue to exist as Research Natural Areas on the Delta National Forest in Sharkey County, Mississippi. In particular, the Over cup Oak (Quercus lyrata) and Redgum (Liquidambar styraciflua) Research Natural Areas pres ent substantial components of the trees for which the areas were named, as well as Quercus nuttallii and smaller components of other species. Recent interest in afforestation has produced a resurgence of interest in restoration of oak forest to abandoned farmland in the region. We have studied small mammal response to restoration on an extensive experiment near the Delta National Forest since 1995. We have also examined small mammal response to a tornado that disturbed approximately half of the Over cup Oak Research Natural Area in 2008. We use these studies to demonstrate how population estimates of small mammals can be obtained from capture-recapture studies, employing different designs, and utilizing Program Capture for population estimation. Small mammal communities in these stands are more species-rich in early succession than in primary forest. The study of response to tornado damage to the Over cup Oak Research Natural Area is complicated by the fact that this particular forest type is very flood-prone, creating obstacles to colonization by small mammals. Analysis of capture-recapture data with robust methods illustrated in this study permits extraction

  8. Nitrogen dynamics in oak model ecosystems subjected to air warming and drought on two different soils.

    Science.gov (United States)

    Kuster, T M; Schleppi, P; Hu, B; Schulin, R; Günthardt-Goerg, M S

    2013-01-01

    Being tolerant to heat and drought, oaks are promising candidates for future forestry in view of climate change in Central Europe. Air warming is expected to increase, and drought decrease soil N availability and thus N supply to trees. Here, we conducted a model ecosystem experiment, in which mixed stands of young oaks (Quercus robur, Q. petraea and Q. pubescens) were grown on two different soils and subjected to four climate treatments during three growing seasons: air warming by 1-2 °C, drought periods (average precipitation reduction of 43-60%), a combination of these two treatments, and a control. In contrast to our hypotheses, neither air warming nor drought significantly affected N availability, whereas total amounts, vertical distribution and availability of soil N showed substantial differences between the two soils. While air warming had no effect on tree growth and N accumulation, the drought treatment reduced tree growth and increased, or tended to increase, N accumulation in the reduced biomass, indicating that growth was not limited by N. Furthermore, (15) N-labelling revealed that this accumulation was associated with an increased uptake of nitrate. On the basis of our results, climate change effects on N dynamics are expected to be less important in oak stands than reduced soil water availability. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  9. Climate effects on cork growth in Cork oak plantations in Sicily (Italy

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available Cork oak (Quercus suber L. is usually dominant in silvopastoral systems in many areas of Sicily, where the trees are debarked periodically for cork production. In spite of the importance of cork and cork oak stands in Sicilian forests and the potential economic scenarios, few research works have been carried out on these systems. Given the importance of cork thickness in cork quality evaluation, the main objective of this work is to study cork growth in cork oak productive stands spread on the north (Nebrodi Mountains and south-east (Iblei Mountains of Sicily. Image analysis techniques were used on cork surfaces of transverse sections of planks to measure cork rings. Dendrochronological analysis was applied to study annual fluctuation on rings growth in relation to various climate parameters in a cork cycle production. Results showed that rainfall, summer drought and temperature are determining factors in controlling cork growth. In siliceous areas of Nebrodi Mountains correlation between cork growth index and rainfall indicates that the rain period from May to September strongly influences phellogen activity. Temperature and water stress indices, on the other hand, show a negative correlation with cork growth. In clay and evolved soils of volcanic plateau of Iblei Mountains January precipitation shows a positive correlation with cork growth index. Also absolute minimum temperature in June and absolute maximum temperature in September show a positive correlation when temperature possibly has influence on phellogen activity during growing season.

  10. Adaptation of Western Oak Seedlings to Yasuj Climate and Analysis of their Leaf Morphology

    Directory of Open Access Journals (Sweden)

    R. Zolfaghari

    2015-12-01

    Full Text Available Analysis of performance and survival rate of different oak species in severe climate of Zagros forests especially under global warming can help with management, conservation and restoration of these species. So, seeds of three oak species of Zagros (Quercus branti, Q. infectoria and Q. libani were collected from Baneh forests and sown in the common gardens of Yasuj. Then, their growth parameters such as collar diameter, height, trunk volume, height and collar increment, number of leaf and survival rate were measured and recorded during the growing season (June and October for the first two years. Also, in order to find a relationship between these traits and leaf morphological and qualitative traits of seedlings, some parameters like leaf area, specific leaf area, number of sprout and branch, bending of seedlings were measured and recorded. Results showed that at early growth age, seedlings of Q. branti and Q. infectoria had the largest and smallest size, respectively. Also, Q. libani seedlings showed a lower survival rate in the second year than other studied species due to the larger seeds. Results of correlation showed that seedlings with larger leaf area, higher number of branch and less straightness had higher growth and survival rate. It can be concluded that Q. infectoria is more susceptive to the increasing period and intensity of drought than other oaks of Zagros species.

  11. Soil moisture in sessile oak forest gaps

    Science.gov (United States)

    Zagyvainé Kiss, Katalin Anita; Vastag, Viktor; Gribovszki, Zoltán; Kalicz, Péter

    2015-04-01

    By social demands are being promoted the aspects of the natural forest management. In forestry the concept of continuous forest has been an accepted principle also in Hungary since the last decades. The first step from even-aged stand to continuous forest can be the forest regeneration based on gap cutting, so small openings are formed in a forest due to forestry interventions. This new stand structure modifies the hydrological conditions for the regrowth. Without canopy and due to the decreasing amounts of forest litter the interception is less significant so higher amount of precipitation reaching the soil. This research focuses on soil moisture patterns caused by gaps. The spatio-temporal variability of soil water content is measured in gaps and in surrounding sessile oak (Quercus petraea) forest stand. Soil moisture was determined with manual soil moisture meter which use Time-Domain Reflectometry (TDR) technology. The three different sizes gaps (G1: 10m, G2: 20m, G3: 30m) was opened next to Sopron on the Dalos Hill in Hungary. First, it was determined that there is difference in soil moisture between forest stand and gaps. Second, it was defined that how the gap size influences the soil moisture content. To explore the short term variability of soil moisture, two 24-hour (in growing season) and a 48-hour (in dormant season) field campaign were also performed in case of the medium-sized G2 gap along two/four transects. Subdaily changes of soil moisture were performed. The measured soil moisture pattern was compared with the radiation pattern. It was found that the non-illuminated areas were wetter and in the dormant season the subdaily changes cease. According to our measurements, in the gap there is more available water than under the forest stand due to the less evaporation and interception loss. Acknowledgements: The research was supported by TÁMOP-4.2.2.A-11/1/KONV-2012-0004 and AGRARKLIMA.2 VKSZ_12-1-2013-0034.

  12. Adaptive genetic variability and differentiation of Croatian and Austrian Quercus robur L. populations at a drought prone field trial

    Directory of Open Access Journals (Sweden)

    Saša Bogdan

    2017-07-01

    Full Text Available Provenance trials, where populations of different geographical origin are tested in a common environment (common garden test, are a tool suited to allow the study of intraspecific adaptive genetic variation. Research of pedunculate oak (Quercus robur L. adaptive genetic variability through analyses of populations in common garden tests has a long tradition. However, pedunculated oak populations originating south-eastern from the Alps have been scarcely studied in this way. This study addresses the adaptive genetic variability and differentiation of pedunculate oak populations originating from Austria and Croatia in a provenance/progeny field trial. Studied plants were six years old and were growing at the trial for three years. After two years of unusually low precipitations height and survival were analysed. The total mean height of all plants in the trial was 137.8 cm and ranged from 123.0 cm to 151.8 cm. The overall mean survival rate was rather high (0.85. Mean population survival ranged from 0.64 to 0.94. Individual narrow-sense heritabilities (hi2, family mean heritabilities (hf2, the coefficients of additive genetic variation (CVA and quantitative genetic differentiation coefficients (QST were calculated. A multivariate regression tree (MRT analysis was used to determine the pattern of genetic differentiation of the populations. Individual heritabilities for height ranged between 0.00 and 0.39. Family mean heritabilities for height were rather low in most populations as well (<0.5. Family mean heritabilities for survival were higher than for height (ranging between 0.00 and 0.77. Calculated QST coefficients (0.25 for height and 0.14 for survival indicated between-population genetic differentiation. The populations were separated into two clusters by MRT analysis regarding a climatic variable, namely Hargreaves’ reference evapotranspiration. Populations originating from comparatively more humid habitats were grouped in the first

  13. Catalytic Rapid Pyrolysis of Quercus variabilis over Nanoporous Catalysts

    Directory of Open Access Journals (Sweden)

    Hyeon Koo Kang

    2015-01-01

    Full Text Available Catalytic rapid pyrolysis of Quercus variabilis, a Korean native tree species, was carried out using Py-GC/MS. Mesoporous MFI, which has both nanopores and micropores, and three nanoporous materials, Al-MCM-41, Al-SBA-15, and γ-Al2O3, were used as the catalyst. The acid sites of mesoporous MFI were strong Brønsted acid sites, whereas those of nanoporous materials were mostly weak acid sites. The composition of the product bio-oil varied greatly depending on the acid characteristics of the catalyst used. Phenolics were the most abundant species in the bio-oil, followed by acids and furanics, obtained over Al-MCM-41 or Al-SBA-15 with weak acid sites, whereas aromatics were the most abundant species produced over mesoporous MFI with strong acid sites, followed by phenolics. Aromatics, phenolics, and furanics are all important chemicals contributing to the improvement of bio-oil quality.

  14. How to identify and manage oak wilt in Texas

    Science.gov (United States)

    D.N. Appel; R.S. Cameron; A.D. Wilson; J.D. Johnson

    2008-01-01

    Transporting unseasoned firewood from diseased red oaks is a potential means of spreading the oak wilt fungus. Oak wilt cannot be transmitted by burning infected firewood, but fungal mats may form on firewood in storage. Presently, no vectors have been proven to transmit the fungus from live oaks to other oak trees, but diseased wood fromany oak species should never be...

  15. First record of the oak gall wasp genus Neuroterus Hartig, 1840 (Hymenoptera, Cynipidae, Cynipini from Central America with description of three new species from Panama and Costa Rica

    Directory of Open Access Journals (Sweden)

    E. Medianero

    2017-05-01

    Full Text Available Three new species of Neuroterus Hartig, 1840 (Hymenoptera: Cynipidae: Cynipini are described from Panama and Costa Rica: Neuroterus elvisi sp. n., Neuroterus pulchrigalla sp. n., and Neuroterus glandiphilus sp. n. The new species are the first of the genus Neuroterus recorded from Central America and the Neotropical region. The new species induce galls on Quercus bumelioides Liebm. (Fagaceae, sect. Quercus, White Oaks. Additional evidence of the presence of other unidentified species of Neuroterus in the sampled area is presented. Diagnostic morphological characters, gall descriptions, distributions, host plant and other biological data of the new species are given and discussed. http://urn:lsid:zoobank.org:pub:48D0C1E1-1D0C-40D8-B890-FFC85AE7A213

  16. THE USE-POTENTIAL OF QUERCUS ALIENA VAR. ACUTESERRATA FOR URBAN PLANTATIONS – BASED ON HABITAT STUDIES IN THE QINLING MOUNTAINS, CHINA

    Directory of Open Access Journals (Sweden)

    Henrik SJÖMAN

    2015-12-01

    Full Text Available Traditionally, a limited number of species and genera dominate the tree stock in streets and urban sites, and recent surveys in European and North American cities show that few species/genera continue to dominate. Yet, over the past decades, a growing proportion of those commonly used species have shown increasing difficulties to cope with urban sites. This has led to considerable and persistent arguments for using a more varied range of trees, including stress-tolerant species, at urban paved sites. This study examined forest systems occurring between 1300-2200 m asl. in the Qinling Mountains, China, in order to evaluate the oriental white oaks (Quercus aliena var. acuteserrata Maximowicz ex Wenzig growth and development in warm and dry forest habitats and hence evaluate its potential for urban paved sites in northern parts of central Europe and in adjoining milder parts of northern Europe. In total, 102 oriental white oak where found in the studied plots and here showed very promising development in habitats experiencing drier conditions than those in park environments in Copenhagen, and is therefore interesting for urban paved sites were the demands of a greater catalogue of tolerant trees are highly needed.

  17. Sulfuryl fluoride fumigation of red oak logs eradicates the oak wilt fungus

    Science.gov (United States)

    Elmer L. Schmidt; Jennifer Juzwik; Brian Schneider

    1997-01-01

    Preliminary field trials using red oak logs from trees dying from oak wilt disease were successful in eliminating oak wilt fungus from sapwood after fumigation with sulfuryl fluoride for 72 h under tarp. These results support earlier laboratory data on the fungitoxicity of sulfuryl fluoride as a potential replacement for methyl bromide of exported red oak veneer logs....

  18. Oak Ridge Leadership Computing Facility (OLCF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Oak Ridge Leadership Computing Facility (OLCF) was established at Oak Ridge National Laboratory in 2004 with the mission of standing up a supercomputer 100 times...

  19. Photosynthetic efficiency of Pedunculate oak seedlings under simulated water stress

    Directory of Open Access Journals (Sweden)

    Popović Zorica

    2010-01-01

    Full Text Available Photosynthetic performance of seedlings of Quercus robur exposed to short-term water stress in the laboratory conditions was assessed through the method of induced fluorometry. The substrate for seedlings was clayey loam, with the dominant texture fraction made of silt, followed by clay and fine sand, with total porosity 68.2%. Seedlings were separated in two groups: control (C (soil water regime in pots was maintained at the level of field water capacity and treated (water-stressed, WS (soil water regime was maintained in the range of wilting point and lentocapillary capacity. The photosynthetic efficiency was 0.642±0.25 and 0.522±0.024 (WS and C, respectively, which was mostly due to transplantation disturbances and sporadic leaf chlorosis. During the experiment Fv/Fm decreased in both groups (0.551±0.0100 and 0.427±0.018 in C and WS, respectively. Our results showed significant differences between stressed and control group, in regard to both observed parameters (Fv/Fm and T½. Photosynthetic efficiency of pedunculate oak seedlings was significantly affected by short-term water stress, but to a lesser extent than by sufficient watering.

  20. Influence of the botanical origin and toasting level on the ellagitannin content of wines aged in new and used oak barrels.

    Science.gov (United States)

    Navarro, María; Kontoudakis, Nikolaos; Gómez-Alonso, Sergio; García-Romero, Esteban; Canals, Joan Miquel; Hermosín-Gutíerrez, Isidro; Zamora, Fernando

    2016-09-01

    The influence of the botanical origin (French oak: Quercus petraea and American oak: Quercus alba) and different toasting levels (light, medium and heavy) on the ellagitannin content of wines aged in oak barrels has been studied. This took place in two consecutive vintages in order to study what happens after the barrels have been already used for one year with another wine. This study was carried out with two red wines (Cabernet Sauvignon) and with two decolored white wines (Macabeo) from vintages 2012 and 2013 in order to work with a simpler matrix which facilitates chemical analysis. The results show that the botanical origin, toasting level and the number of times that the barrels have been used exert a major influence on the final ellagitannin concentration. In general, the behavior of all the individual ellagitannins was very similar to that described for the total ellagitannins. Briefly, the levels of total ellagitannins concentration in the decolored white wine aged for 12months in new French barrels ranged between 31.2mg/L in the lightly toasted and 4.7mg/L in the heavy toasted. In contrast, these levels were quite lower in American new barrels ranging between 3.6mg/L and 0.9mg/L. Finally, the total ellagitannin concentration decreased an average of 63% in the wines aged in the one year used barrels. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Raw hulled shredded acorns from Downy Oak (Quercus pubescens) in the diet of pigs: effects on digestibility and faeces characteristics.

    Science.gov (United States)

    Cappai, M G; Wolf, P; Rust, P; Pinna, W; Kamphues, J

    2013-05-01

    Faeces quality and composition are both of interest to veterinary practitioners dealing with pigs' health and disturbances in the alimentary tract, especially in free-range situations. In the Mediterranean basin, acorns are used as a starch source for fattening pigs, yet little information is available on how that affects faecal quality and digestibility. Therefore, a combined diet containing ripe hulled shredded acorns vs. a pelleted complete diet for finishers was evaluated for the digestibility and faecal consistency. The trial involved eight crossbred pigs, and a matched-pair approach was used to divide animals into two groups, which were fed with two different diets: acorns group (A): n = 4, 70% ripe hulled shredded acorns + 30% pelleted complete diet combined, as fed; control group (C): n = 4, 100% pelleted complete feed. The pigs were housed individually and fed the experimental diets for 8 days; daily feed intake and faeces amounts were recorded and faeces quality assessed. The digestibility of organic matter (OM) and starch of the two diets, as well as of pure acorns, were calculated and compared. Daily feed consumption was significantly higher in group A, but the mean dry matter intake (DMI) per pig was similar in both groups. Dark, firm and consistent faeces were reported for each pig from group A in comparison with group B, whose faeces were paler and softer. Digestibility of OM and starch were lower in group A than in group B (67.8 ± 3.4 vs. 83.9 ± 1.1 and 82.5 ± 3.4 vs. 92.3 ± 2.1 respectively): total tract digestibility of native starch from pure acorns was calculated at 77%. The peculiar consistency of faeces was related to macroscopic acorn hulls, constantly detected in the faeces of all animals sampled in group A. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

  2. Fire scar growth and closure rates in white oak (Quercus alba) and the implications for prescribed burning

    Science.gov (United States)

    Michael C. Stambaugh; Kevin T. Smith; Daniel C. Dey

    2017-01-01

    In burned forestlands, fire scar wounds commonly occur on tree stems as a result of cambial heating. In hardwood forests in particular, wounding can lead to stem decay with the extent of decay being related to scar size and exposure time. Therefore, wound closure rates are important to understand in the context of fire management such that allowing sufficient time for...

  3. A VEGETATION ISLAND WITH WHITE OAK (QUERCUS PUBESCENS WILLD. IN THE SUB-CARPATHIANS OF BUZĂU

    Directory of Open Access Journals (Sweden)

    ŞTEFAN NICOLAE

    2007-12-01

    Full Text Available The vegetation of a forest-steppe type from a part of the river Buzău Basin is presented in this paper. After a short presentation of the natural conditions of the forest Crivineni (near the village Valea Lupului, Buzău county, we are making an analysis of the present-day vegetation, as well as the coenotaxons identified by us in that forest.

  4. Epicormic development in pole-size white oak (Quercus Alba L.) progeny tests three years following crown release

    Science.gov (United States)

    Andrew Meier; Mike R. Saunders

    2016-01-01

    Epicormic development has been traditionally thought to be a response to increased light and to varying vigor and genetics among individuals within a species, but epicormic ontogeny has increasingly been shown to be a more fundamental factor. Previous studies have quantified the impact of tree vigor on epicormic sprouting and epicormic branch size following...

  5. Determination of the main chemical components in Brazilian sugar cane spirit aged in oak (Quercus sp.) barrels

    OpenAIRE

    Parazzi, Clóvis; Arthur, Cecília Marques; Lopes, Jorge José Correa; Borges, Maria Teresa Mendes Ribeiro

    2008-01-01

    A aguardente de cana-de-açúcar ou cachaça é muito apreciada por seu aroma e sabor característico, que podem melhorar pelo envelhecimento em barris de madeira. Durante o envelhecimento muitas transformações ocorrem e alguns compostos novos podem ser incorporados ou formados, enquanto outros desaparecem. Este estudo teve como objetivo avaliar os efeitos da madeira sobre a qualidade e composição química da aguardente quando envelhecida em barris de carvalho. Doze amostras de aguardentes foram ar...

  6. Effect of fire severity on physical and biochemical soil properties in Zagros oak (Quercus brantii Lindl.) forests in Iran

    Science.gov (United States)

    M. Heydari; A. Rostamy; F. Najafi; D. C. Dey

    2017-01-01

    Fire affects the physical and chemical properties and soil biological activity of natural ecosystems. This study was conducted in the Miyan Tang region, Ilam Province in western Iran. The study site was 110 hectares, where we sampled soils in areas that were classified by fire severity: low (LS), high (HS) and medium severity (MS), and unburned (UB), which served as...

  7. A HIERARCHICAL ANALYSIS OF MINISATELLITE DNA GENETIC DIVERSITY IN GAMBEL OAK (QUERCUS GAMBELII NUTT.; FAGACEAE). (R826602)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  8. Direct effects of elevated UV-B radiation on the decomposition of Quercus robur leaf litter

    International Nuclear Information System (INIS)

    Newsham, K.K.; McLeod, A.R.; Roberts, J.D.; Greenslade, P.D.; Emmett, B.A.

    1997-01-01

    Decomposing Quercus robur L. leaf litter was exposed for 64 weeks at an outdoor facility to supplemental levels of UV-B radiation (280-315 nm) under treatment arrays of cellulose diacetate-filtered fluorescent lamps which also produce UV-A radiation (315-400 nm). Litter was also exposed to UV-A radiation alone under control arrays of polyester-filtered lamps and to ambient levels of solar radiation under arrays of unenergised lamps. The treatment corresponded to a 30% elevation above the ambient erythemally-weighted level of UV-B radiation. Litter was sampled after 11, 39 and 64 weeks and was examined for differences in mass loss, decomposition constants (k), chemical composition and the abundances of saprotrophic fungi. No effects of UV radiation on k values were recorded, but after 11 weeks, percentage mass loss of litter exposed to UV-B radiation under treatment arrays was 3% lower than under control arrays and 2% lower than under ambient arrays. After 39 weeks, litters exposed to UV-A radiation under control arrays had 10% lower total nitrogen contents and 13% higher C:N ratios than those litters exposed beneath ambient arrays. At the last sampling, litters exposed to supplemental UV-B radiation had 5% higher carbon contents than those under ambient arrays. A 2.4-fold increase in the frequency of lamina particles of litter that were uncolonised by fungi was recorded in litter exposed to UV-B radiation under treatment arrays, compared to ambient arrays. The abundances of the saprotrophic fungi Cladosporium spp. and Acremonium persicinum (Nicot) W. Gams were decreased by 50% and 91%, respectively, under UV-B treatment arrays compared to ambient arrays, and the abundance of coelomycete conidiomata recorded on leaves was increased by 12% under treatment arrays, compared to ambient. Dactylella spp. were not recorded on litter exposed to UV-A radiation under control arrays and UV-A radiation applied under control and treatment arrays apparently increased the

  9. Analysis of BAC end sequences in oak, a keystone forest tree species, providing insight into the composition of its genome

    Directory of Open Access Journals (Sweden)

    Le Provost Grégoire

    2011-06-01

    Full Text Available Abstract Background One of the key goals of oak genomics research is to identify genes of adaptive significance. This information may help to improve the conservation of adaptive genetic variation and the management of forests to increase their health and productivity. Deep-coverage large-insert genomic libraries are a crucial tool for attaining this objective. We report herein the construction of a BAC library for Quercus robur, its characterization and an analysis of BAC end sequences. Results The EcoRI library generated consisted of 92,160 clones, 7% of which had no insert. Levels of chloroplast and mitochondrial contamination were below 3% and 1%, respectively. Mean clone insert size was estimated at 135 kb. The library represents 12 haploid genome equivalents and, the likelihood of finding a particular oak sequence of interest is greater than 99%. Genome coverage was confirmed by PCR screening of the library with 60 unique genetic loci sampled from the genetic linkage map. In total, about 20,000 high-quality BAC end sequences (BESs were generated by sequencing 15,000 clones. Roughly 5.88% of the combined BAC end sequence length corresponded to known retroelements while ab initio repeat detection methods identified 41 additional repeats. Collectively, characterized and novel repeats account for roughly 8.94% of the genome. Further analysis of the BESs revealed 1,823 putative genes suggesting at least 29,340 genes in the oak genome. BESs were aligned with the genome sequences of Arabidopsis thaliana, Vitis vinifera and Populus trichocarpa. One putative collinear microsyntenic region encoding an alcohol acyl transferase protein was observed between oak and chromosome 2 of V. vinifera. Conclusions This BAC library provides a new resource for genomic studies, including SSR marker development, physical mapping, comparative genomics and genome sequencing. BES analysis provided insight into the structure of the oak genome. These sequences will be

  10. Resource use and efficiency, and stomatal responses to environmental drivers of oak and pine species in an Atlantic Coastal Plain forest

    Directory of Open Access Journals (Sweden)

    Heidi J Renninger

    2015-05-01

    Full Text Available Pine-oak ecosystems are globally distributed even though differences in anatomy and leaf habit between many co-occurring oaks and pines suggest different strategies for resource use, efficiency and stomatal behavior. The New Jersey Pinelands contain sandy soils with low water- and nutrient-holding capacity providing an opportunity to examine trade-offs in resource uptake and efficiency. Therefore, we compared resource use in terms of transpiration rates and leaf nitrogen content and resource-use efficiency including water-use efficiency (WUE via gas exchange and leaf carbon isotopes and photosynthetic nitrogen-use efficiency (PNUE between oaks (Quercus alba, Q. prinus, Q. velutina and pines (Pinus rigida, P. echinata. We also determined environmental drivers (vapor pressure deficit (VPD, soil moisture, solar radiation of canopy stomatal conductance (GS estimated via sap flow and stomatal sensitivity to light and soil moisture. Net assimilation rates were similar between genera, but oak leaves used about 10% more water and pine foliage contained about 20% more N per unit leaf area. Therefore, oaks exhibited greater PNUE while pines had higher WUE based on gas exchange, although WUE from carbon isotopes was not significantly different. For the environmental drivers of GS, oaks had about 10% lower stomatal sensitivity to VPD normalized by reference stomatal conductance compared with pines. Pines exhibited a significant positive relationship between shallow soil moisture and GS, but only GS in Q. velutina was positively related to soil moisture. In contrast, stomatal sensitivity to VPD was significantly related to solar radiation in all oak species but only pines at one site. Therefore, oaks rely more heavily on groundwater resources but have lower WUE, while pines have larger leaf areas and nitrogen acquisition but lower PNUE demonstrating a trade-off between using water and nitrogen efficiently in a resource-limited ecosystem.

  11. Contact allergy to oak moss

    DEFF Research Database (Denmark)

    Bernard, Guillaume; Giménez-Arnau, Elena; Rastogi, Suresh Chandra

    2003-01-01

    In addition to pure synthetic fragrance materials several natural extracts are still in use in the perfume industry. Among them oak moss absolute, prepared from the lichen Evernia prunastri (L.) Arch., is considered a major contact sensitizer and is therefore included in the fragrance mix used...... for diagnosing perfume allergy. The process of preparing oak moss absolute has changed during recent years and, even though several potential sensitizers have been identified from former benzene extracts, its present constituents and their allergenic status are not clear. In the study reported here, we applied...

  12. Topographic position modulates the mycorrhizal response of oak trees to interannual rainfall variability.

    Science.gov (United States)

    Querejeta, José I; Egerton-Warburton, Louise M; Allen, Michael F

    2009-03-01

    California coast live oak (Quercus agrifolia) forms tripartite symbiotic associations with arbuscular (AMF) and ectomycorrhizal (EMF) fungi. We selected oak individuals differing in topographic position and depth to groundwater (mesic valley vs. xeric hill sites) to investigate changes of tree mycorrhizal status in response to interannual rainfall variability. EMF root colonization, as well as hyphal abundance and viability in upper rhizosphere soil (0-30 cm), were negatively affected by severe multi-year drought, although not to the same extent in each topographic location. Oak trees growing in hill sites showed EMF colonization levels 19%) in upper roots during drought. EMF root colonization increased sharply at both topographic positions during the ensuing wet year (78% in valley, 49% in hill), which indicates that the mycorrhizal status of roots in upper rhizosphere soil is highly responsive to interannual rainfall variability. Across sites and years, percentage EMF colonization and soil hyphal density and viability were strongly positively correlated with soil moisture potential, but percentage AMF root colonization was not. Interestingly, changes in percentage EMF root colonization and density of viable hyphae between a wet and a dry year were proportionally much greater in xeric hill sites than in mesic valley sites. The mycorrhizal status of oak trees was particularly responsive to changes in soil moisture at the hill sites, where roots in upper rhizosphere soil shifted from almost exclusively AMF during severe drought to predominantly EMF during the ensuing wet year. By contrast, the mycorrhizal status of oaks in the valley sites was less strongly coupled to current meteorological conditions, as roots in upper soil layers remained predominantly EMF during both a dry and a wet year. Canopy shading and hydraulic lift by oaks in valley sites likely contributed to maintain the integrity and viability of EMF roots and extraradical hyphae in upper rhizosphere

  13. Oak habitat recovery on California's largest islands: Scenarios for the role of corvid seed dispersal

    Science.gov (United States)

    Pesendorfer, Mario B.; Baker, Christopher M.; Stringer, Martin; McDonald-Madden, Eve; Bode, Michael; McEachern, A. Kathryn; Morrison, Scott A.; Sillett, T. Scott

    2018-01-01

    Seed dispersal by birds is central to the passive restoration of many tree communities. Reintroduction of extinct seed dispersers can therefore restore degraded forests and woodlands. To test this, we constructed a spatially explicit simulation model, parameterized with field data, to consider the effect of different seed dispersal scenarios on the extent of oak populations. We applied the model to two islands in California's Channel Islands National Park (USA), one of which has lost a key seed disperser.We used an ensemble modelling approach to simulate island scrub oak (Quercus pacifica) demography. The model was developed and trained to recreate known population changes over a 20-year period on 250-km2 Santa Cruz Island, and incorporated acorn dispersal by island scrub-jays (Aphelocoma insularis), deer mice (Peromyscus maniculatus) and gravity, as well as seed predation. We applied the trained model to 215-km2 Santa Rosa Island to examine how reintroducing island scrub-jays would affect the rate and pattern of oak population expansion. Oak habitat on Santa Rosa Island has been greatly reduced from its historical extent due to past grazing by introduced ungulates, the last of which were removed by 2011.Our simulation model predicts that a seed dispersal scenario including island scrub-jays would increase the extent of the island scrub oak population on Santa Rosa Island by 281% over 100 years, and by 544% over 200 years. Scenarios without jays would result in little expansion. Simulated long-distance seed dispersal by jays also facilitates establishment of discontinuous patches of oaks, and increases their elevational distribution.Synthesis and applications. Scenario planning provides powerful decision support for conservation managers. We used ensemble modelling of plant demographic and seed dispersal processes to investigate whether the reintroduction of seed dispersers could provide cost-effective means of achieving broader ecosystem restoration goals on

  14. Searching for early-warning signals of impending dieback and death in Mediterranean oaks

    Science.gov (United States)

    Colangelo, Michele; Ripullone, Francesco; Julio Camarero, Jesus; De Micco, Veronica; Gazol, Antonio; Gentilesca, Tiziana; Borghetti, Marco

    2017-04-01

    In recent decades, forest dieback episodes have been recorded worldwide affecting different tree species. In particular, several cases of widespread dieback and increased mortality rates have been described for Mediterranean oak (Quercus spp.) species. These dieback cases are revealing the high vulnerability of Mediterranean oaks, manifested as a loss in tree vigour (leaf shedding, canopy and shoot dieback), growth decline and sometimes tree death, as a consequence of temperatures rising at unprecedented rates and drying trends. However, in the wake of the so-called 'oak decline phenomenon', the attention on these species has generally been limited, perhaps because they are often regarded as well-adapted to the dry conditions typical of Mediterranean areas. Indeed, according to recent studies, the reduced size, the ability to sprout and the anisohydric behavior of Mediterranean oak species (reduced control of water loss and high stomatal conductance rates) would make them better adapted to withstand heat and drought stress then taller and non-sprouting isohydric species (e.g. conifer, with strict control of water loss by closing stomata). Here, we investigated the vulnerability of Mediterranean oaks by comparing neighboring living and recently dead trees in species with low (Q. pubescens), intermediate (Q. cerris, Q. frainetto) and high (Q. robur) sensitivity to water shortage. We analysed changes in tree vigour using tree-ring width and functional wood anatomical traits as proxies to search for early-warning signals of dieback, in connection with the main proposed dieback mechanisms (hydraulic failure and/or carbon starvation). We also modeled the probability of tree death as a function of tree size (diameter, height) by quantifying recent changes in growth and wood anatomy along tree-ring series. Contrary to the general concept that trees tend to experience increasing cavitation risk with increasing height, our studies show that smaller oaks are more prone to die

  15. Dynamics of cesium-134 and biomass in treated and untreated turkey oak leaf-litter bags

    International Nuclear Information System (INIS)

    Croom, J.M.; Ragsdale, H.L.

    1978-01-01

    Litter bags were prepared from leaves harvested in late fall from turkey oak trees (Quercus laevis) tagged with 134 Cs. Untreated bags and bags treated by soaking in 1000 ppM HgCl 2 were placed in the field on Dec. 7, 1974. Five bags of each treatment were retrieved at 7-, 14-, and 30-day intervals as the experiment progressed. Treated bags remained free of visible fungal hyphae growth for 12 weeks. Untreated bags had lost more weight but less 134 Cs than treated bags after 14 and 56 days, respectively. After 9 months, untreated bags had lost 33% weight and 90% 134 Cs. Although 134 Cs is rapidly leached from litter (ecological half-life approximately equal to 12 weeks), some is retained by fungal hyphae on leaf-litter surfaces. This mechanism of mineral retention in the litter layer could represent adaptation at the ecosystem level for nutrient conservation

  16. Floristic study in an oak grove of the flora and fauna sanctuary of Iguaque (Boyaca, Colombia)

    International Nuclear Information System (INIS)

    Marin Corba, Cesar A; Betancur, Julio

    1997-01-01

    The floristic diversity of an oak Andean forest was studied at the national reserve Santuario de flora y fauna de Iguaque (Boyaca, Colombia). All individuals with DAP > 2 .5 were measured and registered in ten 50 x 2 m transects for a total of 0.1 ha. There were found 384 individuals, 53 species, 27 families and 34 genera; the most species-rich were Ericaceae (7), Lauraceae (5) and Myrsinaceae (5). The results show a forest with low diversity in which a few species predominate; the species with higher important value index (ivi) were quercus humboldtii (34 %), Weinmannia tomentosa (21.2 %), Clusia inesiana (4.8 %), Viburnum tinoides (4.7 %) and Ternstroemia meridionalis (4.6 %)

  17. 2-DE proteomics analysis of drought treated seedlings of Quercus ilex supports a root active strategy for metabolic adaptation in response to water shortage.

    Science.gov (United States)

    Simova-Stoilova, Lyudmila P; Romero-Rodríguez, Maria C; Sánchez-Lucas, Rosa; Navarro-Cerrillo, Rafael M; Medina-Aunon, J Alberto; Jorrín-Novo, Jesús V

    2015-01-01

    Holm oak is a dominant tree in the western Mediterranean region. Despite being well adapted to dry hot climate, drought is the main cause of mortality post-transplanting in reforestation programs. An active response to drought is critical for tree establishment and survival. Applying a gel-based proteomic approach, dynamic changes in root proteins of drought treated Quercus ilex subsp. Ballota [Desf.] Samp. seedlings were followed. Water stress was applied on 20 day-old holm oak plantlets by water limitation for a period of 10 and 20 days, each followed by 10 days of recovery. Stress was monitored by changes in water status, plant growth, and electrolyte leakage. Contrary to leaves, holm oak roots responded readily to water shortage at physiological level by growth inhibition, changes in water status and membrane stability. Root proteins were extracted using trichloroacetate/acetone/phenol protocol and separated by two-dimensional electrophoresis. Coomassie colloidal stained gel images were analyzed and spot intensity data subjected to multivariate statistical analysis. Selected consistent spots in three biological replicas, presenting significant changes under stress, were subjected to MALDI-TOF mass spectrometry (peptide mass fingerprinting and MS/MS). For protein identification, combined search was performed with MASCOT search engine over NCBInr Viridiplantae and Uniprot databases. Data are available via ProteomeXchange with identifier PXD002484. Identified proteins were classified into functional groups: metabolism, protein biosynthesis and proteolysis, defense against biotic stress, cellular protection against abiotic stress, intracellular transport. Several enzymes of the carbohydrate metabolism decreased in abundance in roots under drought stress while some related to ATP synthesis and secondary metabolism increased. Results point at active metabolic adjustment and mobilization of the defense system in roots to actively counteract drought stress.

  18. Effect of feeding tannin degrading bacterial culture (Streptococcus gallolyticus strain TDGB 406) on nutrient utilization, urinary purine derivatives and growth performance of goats fed on Quercus semicarpifolia leaves.

    Science.gov (United States)

    Kumar, K; Chaudhary, L C; Agarwal, N; Kamra, D N

    2014-10-01

    To study the effect of supplementation of tannin degrading bacterial culture (Streptococcus gallolyticus strain TDGB 406) on growth performance, nutrient utilization and urinary purine derivatives of goats fed on oak (Quercus semicarpifolia) leaves. For growth study, eighteen billy goats (4 month old, average body weight 9.50 ± 1.50 kg) were distributed into three groups of six animals each. The animals of group 1 served as control while animals of groups 2 (T1) and 3 (T2) were given (@ 5 ml/kg live weight) autoclaved and live culture of isolate TDGB 406 (10(6) cells/ml) respectively. The animals were fed measured quantity of dry oak leaves as the main roughage source and ad libitum maize hay along with fixed quantity of concentrate mixture. The feeding of live culture of isolate TDGB 406 (probiotic) did not affect dry matter intake and digestibility of nutrients except that of dry matter and crude protein, which was higher in T2 group as compared to control. All the animals were in positive nitrogen balance. There was no significant effect of feeding isolate TDGB 406 on urinary purine derivatives (microbial protein production) in goats. The body weight gain and average live weight gain was significantly higher (p = 0.071) in T2 group as compared to control. Feed conversion efficiency was also better in the goats fed on live culture of TDGB 406 (T2). The feeding of tannin degrading bacterial isolate TDGB 406 as probiotic resulted in improved growth performance and feed conversion ratio in goats fed on oak leaves as one of the main roughage source. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

  19. Seasonal dynamics of secondary growth and xylem anatomy in two coexisting Mediterranean Quercus; Dinamica estacional del crecimiento secundario y anatomia del xilema en dos Quercus mediterraneos que coexisten

    Energy Technology Data Exchange (ETDEWEB)

    Albuixech, J.; Camarero, J. J.; Montserrat-Marti, G.

    2012-11-01

    The contribution of secondary growth's patterns and wood anatomy on the coexistence of two species of Quercus (Quercus ilex subsp ballota diffused porous wood and Quercus faginea ring porous wood) were studied in a location with continental Mediterranean climate, which has been studied during two years with contrasted climatology. According to our results secondary growth pattern of Q. faginea is concentrated in the spring, starting before, and responding more than Q. ilex to a rainfall increase during this period. Q. ilex extends wood formation into the fall and late summer growth. Q. ilex growth during the fall and late summer has a greater importance in terms of theoretical hydraulic conductivity than in Q. faginea, which concentrates hydraulic conductivity in spring vessels. Therefore, different response of wood phenology formation and xylem anatomy in both species to the seasonal pattern of precipitation could contribute to explain the coexistence of Q. ilex and Q. faginea. (Author) 48 refs.

  20. Remote sensing upscaling of interception loss from isolated oaks: Sardon catchment case study, Spain

    Science.gov (United States)

    Hassan, S. M. Tanvir; Ghimire, Chandra Prasad; Lubczynski, Maciek W.

    2017-12-01

    Tree interception loss from two Mediterranean oak species, Quercus ilex (Q.i.) and Quercus pyrenaica (Q.p.), was estimated during 2-year period (1 October 2011 to 30 September 2013) in sparsely vegetated Sardon catchment (∼80 km2, Spain) by: i) rainfall, throughfall and stemflow measurements; ii) Gash model temporal extrapolation; and iii) remote-sensing spatial upscaling. The annual, measured tree interception losses (Im) of Q.i. and Q.p. in the first year were 51% and 16% of P (335 mm) and in the second, 46% and 10% of P (672 mm), respectively. The revised Gash analytical model of rainfall interception loss, extrapolated well the Im temporal variability of Q.i. and Q.p., provided the throughfall-based, and not Pennman-Monteith-based, average wet canopy evaporation rates were used. Finally, a novel method of spatial upscaling of a tree-based interception loss into plot- and catchment-scale, using per-species, reference tree interception loss and object-attributes derived from satellite imagery, was proposed. The interception losses from Q.i. and Q.p. were upscaled first into two homogeneous plots (1-ha each and both with ∼20% canopy cover), one with Q.i. and the other with Q.p. oaks and then into the entire Sardon catchment with ∼7% canopy cover. The obtained annual-mean, plot interception losses were 9.5% of P in evergreen Q.i. and 2.5% of P in deciduous Q.p. plot. The annual-mean catchment interception loss was 1.4% of P. The proposed upscaling method is expected to improve catchment water balances, replacing common arbitrary or literature based tree interception loss estimates.

  1. Oak bark allometry and fire survival strategies in the Chihuahuan desert Sky Islands, Texas, USA.

    Directory of Open Access Journals (Sweden)

    Dylan W Schwilk

    Full Text Available Trees may survive fire through persistence of above or below ground structures. Investment in bark aids in above-ground survival while investment in carbohydrate storage aids in recovery through resprouting and is especially important following above-ground tissue loss. We investigated bark allocation and carbohydrate investment in eight common oak (Quercus species of Sky Island mountain ranges in west Texas. We hypothesized that relative investment in bark and carbohydrates changes with tree age and with fire regime: We predicted delayed investment in bark (positive allometry and early investment in carbohydrates (negative allometry under lower frequency, high severity fire regimes found in wetter microclimates. Common oaks of the Texas Trans-Pecos region (Quercus emoryi, Q. gambelii, Q. gravesii, Q. grisea, Q. hypoleucoides, Q. muehlenbergii, and Q. pungens were sampled in three mountain ranges with historically mixed fire regimes: the Chisos Mountains, the Davis Mountains and the Guadalupe Mountains. Bark thickness was measured on individuals representing the full span of sizes found. Carbohydrate concentration in taproots was measured after initial leaf flush. Bark thickness was compared to bole diameter and allometries were analyzed using major axis regression on log-transformed measurements. We found that bark allocation strategies varied among species that can co-occur but have different habitat preferences. Investment patterns in bark were related to soil moisture preference and drought tolerance and, by proxy, to expected fire regime. Dry site species had shallower allometries with allometric coefficients ranging from less than one (negative allometry to near one (isometric investment. Wet site species, on the other hand, had larger allometric coefficients, indicating delayed investment to defense. Contrary to our expectation, root carbohydrate concentrations were similar across all species and sizes, suggesting that any differences in

  2. Oak bark allometry and fire survival strategies in the Chihuahuan desert Sky Islands, Texas, USA.

    Science.gov (United States)

    Schwilk, Dylan W; Gaetani, Maria S; Poulos, Helen M

    2013-01-01

    Trees may survive fire through persistence of above or below ground structures. Investment in bark aids in above-ground survival while investment in carbohydrate storage aids in recovery through resprouting and is especially important following above-ground tissue loss. We investigated bark allocation and carbohydrate investment in eight common oak (Quercus) species of Sky Island mountain ranges in west Texas. We hypothesized that relative investment in bark and carbohydrates changes with tree age and with fire regime: We predicted delayed investment in bark (positive allometry) and early investment in carbohydrates (negative allometry) under lower frequency, high severity fire regimes found in wetter microclimates. Common oaks of the Texas Trans-Pecos region (Quercus emoryi, Q. gambelii, Q. gravesii, Q. grisea, Q. hypoleucoides, Q. muehlenbergii, and Q. pungens) were sampled in three mountain ranges with historically mixed fire regimes: the Chisos Mountains, the Davis Mountains and the Guadalupe Mountains. Bark thickness was measured on individuals representing the full span of sizes found. Carbohydrate concentration in taproots was measured after initial leaf flush. Bark thickness was compared to bole diameter and allometries were analyzed using major axis regression on log-transformed measurements. We found that bark allocation strategies varied among species that can co-occur but have different habitat preferences. Investment patterns in bark were related to soil moisture preference and drought tolerance and, by proxy, to expected fire regime. Dry site species had shallower allometries with allometric coefficients ranging from less than one (negative allometry) to near one (isometric investment). Wet site species, on the other hand, had larger allometric coefficients, indicating delayed investment to defense. Contrary to our expectation, root carbohydrate concentrations were similar across all species and sizes, suggesting that any differences in below ground

  3. Monitoring drought impact on Mediterranean oak savanna vegetation using remote sensing

    Science.gov (United States)

    González-Dugo, Maria P.; Carpintero, Elisabet; Andreu, Ana

    2015-04-01

    A holm oak savanna, known as dehesa in Spain and montado in Portugal, is the largest agroforest ecosystem in Europe, covering about 3 million hectares in the Iberian Peninsula and Greece (Papanastasis et al., 2004). It is considered an example of sustainable land use, supporting a large number of species and diversity of habitats and for its importance in rural development and economy (Plieninger et al., 2001). It is a combination between an agricultural and a naturally vegetated ecosystem, consisting of widely-spaced oak trees (mostly Quercus Ilex and Quercus suber) combined with a sub-canopy composed by crops, annual grassland and/or shrubs. It has a Mediterranean climate with severe periodic droughts. In the last decades, this system is being exposed to multiple threats derived from socio-economic changes and intensive agricultural use, which have caused environmental degradation, including tree decline, changes in soil properties and hydrological processes, and an increase of soil erosion (Coelho et al., 2004). Soil water dynamics plays a central role in the current decline and reduction of forested areas that jeopardizes the preservation of the system. In this work, a series of remotely sensed images since 1990 to present was used to evaluate the effect of several drought events occurred in the study area (1995, 2009, 2010/2011) on the tree density and water status. Data from satellites Landsat and field measurements have been combined in a spectral mixture model to assess separately the evolution of tree, dry grass and bare soil ground coverage. Only summer images have been used to avoid the influence of the green herbaceous layer on the analysis. Thermal data from the same sensors and meteorological information are integrated in a two source surface energy balance model to compute the Evaporative Stress Index (ESI) and evaluate the vegetation water status. The results have provided insights about the severity of each event and the spatial distribution of

  4. Patterns of contemporary hybridization inferred from paternity analysis in a four-oak-species forest

    Directory of Open Access Journals (Sweden)

    Gailing Oliver

    2009-12-01

    Full Text Available Abstract Background Few studies address the issue of hybridization in a more than two-species context. The species-rich Quercus complex is one of the systems which can offer such an opportunity. To investigate the contemporary pattern of hybridization we sampled and genotyped 320 offspring from a natural mixed forest comprising four species of the European white oak complex: Quercus robur, Q. petraea, Q. pubescens, and Q. frainetto. Results A total of 165 offspring were assigned unambiguously to one of the pollen donors within the study plot. The minimum amount of effective pollen originating from outside the plot varied markedly among the seed parents, ranging from 0.18 to 0.87. The majority of the successful matings (64.1% occurred between conspecific individuals indicating the existence of reproductive barriers between oak species. However, the isolation was not complete since we found strong evidence for both first-generation (8.4% and later-generation hybrids (27.5%. Only two out of eight seed parents, belonging to Q. petraea and Q. robur, showed a high propensity to hybridize with Q. pubescens and Q. petraea, respectively. Significant structure of the effective pollen pools (Φpt = 0.069, P = 0.01 was detected in our sample. However, no support was found for the isolation by distance hypothesis. The proportion of hybrids was much higher (79% in the seed generation when compared to the adult tree generation. Conclusion First-generation hybrids were observed only between three out of six possible species combinations. Hybrids between one pair of species preferred to mate with one of their parental species. The observation of first and later-generation hybrids in higher frequency in acorns than in adults might be explained by selection against hybrid genotypes, the history of this uneven-aged forest or past introgression between species.

  5. Fuel wood properties of some oak tree species of Manipur, India.

    Science.gov (United States)

    Meetei, Shougrakpam Bijen; Singh, E J; Das, Ashesh Kumar

    2015-07-01

    Five indigenous oak tree species, i.e., Castanopsis indica (Roxb. ex Lindl.) A.DC., Lithocarpus fenestratus (Roxb.) Rehder, Lithocarpus pachyphyllus (Kurz) Rehder, Lithocarpus polystachyus (Wall. ex A.DC.) Rehder and Quercus serrata Murray were estimated for their wood properties such as calorific value, density, moisture content and ash content from a sub-tropical forest of Haraothel hill, Senapati District, Manipur. Wood biomass components were found to have higher calorific value (kJ g(-)) than bark components. The calorific values for tree species were found highest in L. pachyphyllus (17.99 kJ g(-1)) followed by C. indica (17.98 kJ g1), L. fenestratus (17.96 kJ g"), L. polystachyus (17.80 kJ g(-1)) and Q. serrata (17.49 kJ g(-1)). Calorific values for bole bark, bole wood and branch bark were found significantly different (F > 3.48 at p = 0.05) in five oak tree species. Percentage of ash on dry weight basis was found to be highest in Q. serrata (4.73%) and lowest in C. indica (2.19%). Ash content of tree components gives a singnificant factor in determining fuelwood value index (FVI). Of all the five oak tree species, Q. serrata exhibited highest value of wood density (0.78 g cm-) and lowest was observed in C. indica (0.63 g cm(-3)). There was significant correlation between wood density (p L. pachyphyllus (898.41)> L. polystachyus (879.02)> L. fenestratus (824.61)> Q. serrata (792.50). Thus, the present study suggests that C. indica may be considered as a fuelwood oak tree species in Manipur.

  6. ESTIMACIÓN DE LA BIOMASA FORESTAL PARA LAS ESPECIES QUERCUS ROTUNDIFOLIA Y QUERCUS SUBER BASADA EN IMÁGENES DEL SATÉLITE QUICKBIRD

    OpenAIRE

    Sousa, Adélia; Marques da Silva, José; Gonçalves, Ana Cristina; Mesquita, Paulo; Silva, Luis; Baptista, F.J.

    2013-01-01

    para una buena gestión. Actualmente las técnicas de inventario y monitoreo de biomasa forestal son usualmente lentas, muy trabajosas y de elevado coste, verificándose así la necesidad de desarrollar otras técnicas, que sean fiables y con costes relativamente reducidos. El objetivo de este estudio es desarrollar una metodología para estimar la biomasa forestal de las especies Quercus rotundifolia y Quercus suber basada en imágenes del satélite QuickBird. La estimación de la biomasa...

  7. Sudden oak death online symposium

    Science.gov (United States)

    S.D. Cohen; J., eds Juzwik

    2003-01-01

    This symposium is being made available to all who have an interest in the recent appearance of Sudden Oak Death, a plant disease with the potential to severely impact nursery growers, shippers, the lumber and wood products industry, landscapers, government programs and others. Scientific presentations dealing with the current status of the disease and ongoing research...

  8. Oak Ridge Geochemical Reconnaissance Program

    International Nuclear Information System (INIS)

    Arendt, J.W.

    1977-03-01

    The Oak Ridge reconnaissance program is responsible for the geochemical survey in a 12-state area covering Texas, Oklahoma, Kansas, Nebraska, South Dakota, North Dakota, Minnesota, Wisconsin, Michigan, Iowa, Indiana, and Illinois as part of the National Uranium Resource Evaluation Program. The program concept is outlined and the planning and organization of the program is discussed

  9. Oak woodlands as wildlife habitat

    Science.gov (United States)

    W. Tietje; K. Purcell; S. Drill

    2005-01-01

    This chapter provides local planners and policymakers with information on the diversity and abundance of oak woodland wildlife, wildlife habitat needs, and how local planning activities can influence wildlife abundance and diversity. Federal and state laws, particularly the federal and California Endangered Species Act and the California Environmental Quality Act (CEQA...

  10. Facilitation of Quercus ilex recruitment by shrubs in Mediterranean open woodlands

    NARCIS (Netherlands)

    Smit, Christian; den Ouden, Jan; Diaz, Mario

    Question: Insufficient tree regeneration threatens the long-term persistence of biodiverse Mediterranean open oak woodlands. Could shrubs, scarce due to decades of management ( clearing and ploughing), facilitate holm oak recruitment at both acorn and seedling stages? Location: Open oak woodlands in

  11. Variability of acorn anatomical characteristics in Quercus robur L. genotypes

    Directory of Open Access Journals (Sweden)

    Nikolić Nataša P.

    2010-01-01

    Full Text Available The aim of this study was to examine variability of acorn anatomical characteristics in seventeen Quercus robur L. genotypes. Acorns were collected in clonal seed orchard Banov Brod (Srem, Vojvodina, Serbia. Microscopic measurements were done for pericarp (total thickness, thickness of exocarp and mesocarp, seed coat (total thickness, thickness of outer epidermis, parenchyma, and inner epidermis, and embryo axis (diameter, thickness of cortical region, and diameter of stellar zone. Obtained results revealed certain divergence between genotypes. The thickness of pericarp varied from 418 to 559 mm (genotypes 20 and 22, respectively. On average, the participation of exocarp in the total thickness of pericarp was 36.3%, of mesocarp 61.0%, while of endocarp 2.6%. The thickness of seed coat for individual genotypes ranged from 71 mm (genotype 28 to 157 mm (genotype 38. In addition, anatomic parameters of embryo axis varied among studied genotypes. The lowest cortical zone thickness and stellar zone diameter were measured in genotype 40, while the highest values in genotype 33.

  12. Blue Ocean Thinking

    Science.gov (United States)

    Orem, Donna

    2016-01-01

    This article describes a concept called the "blue ocean thinking strategy," developed by W. Chan Kim and Renée Mauborgne, professors at INSEAD, an international graduate school of business in France. The "blue ocean" thinking strategy considers opportunities to create new markets for services, rather than focusing solely on…

  13. Respuesta plástica a la luz y al agua en cuatro especies mediterráneas del género Quercus (Fagaceae Plastic response to light and water in four Mediterranean Quercus species (Fagaceae

    Directory of Open Access Journals (Sweden)

    JOSÉ L QUERO

    2008-09-01

    alcanzada mediante diferentes estrategias.Light and water availability are two of the main factors that regulate growth and survival of Mediterranean woody plants. The objective of this study is to investigate the plastic response of seedlings of four Mediterranean Quercus species to these factors, as well as to determine what traits are more plastic to one or another factor. Our hypothesis was that physiological variables are more plastic than structural variables. We cultivated in controlled conditions seedlings of Quercus ilex ssp. ballota, Q. súber, Q. pyrenaica and Q. canariensis in three treatments of light (100, 27 and 3 % of incident light and with abundant water. On late spring, watering was stopped for half of the seedlings, so there were two water treatments (irrigation versus no-irrigation within each treatment of light. Several physiological traits were studied: photosynthetic and respiration rate, light compensation and saturation points, stomatal conductance, water use and nitrogen use efficiency. We also evaluated different structural traits were studied such as leaf area, specific leaf area, leaf nitrogen and carbon concentrations, and a chlorophyll index. Changes in water availability induced low plastic responses of structural traits, whereas responses of physiological traits were relatively higher. On the other hand, there were not significant differences in the plastic response of structural or physiological traits to changes in light availability. In these Mediterranean oak species, the higher response to light could be linked to a shade tolerance strategy and the low response to water (i.e., canalization could be related to drought tolerant strategy, thus indicating that tolerance to low-resources may be attained through different strategies.

  14. Stand density, tree social status and water stress influence allocation in height and diameter growth of Quercus petraea (Liebl.).

    Science.gov (United States)

    Trouvé, Raphaël; Bontemps, Jean-Daniel; Seynave, Ingrid; Collet, Catherine; Lebourgeois, François

    2015-10-01

    Even-aged forest stands are competitive communities where competition for light gives advantages to tall individuals, thereby inducing a race for height. These same individuals must however balance this competitive advantage with height-related mechanical and hydraulic risks. These phenomena may induce variations in height-diameter growth relationships, with primary dependences on stand density and tree social status as proxies for competition pressure and access to light, and on availability of local environmental resources, including water. We aimed to investigate the effects of stand density, tree social status and water stress on the individual height-circumference growth allocation (Δh-Δc), in even-aged stands of Quercus petraea Liebl. (sessile oak). Within-stand Δc was used as surrogate for tree social status. We used an original long-term experimental plot network, set up in the species production area in France, and designed to explore stand dynamics on a maximum density gradient. Growth allocation was modelled statistically by relating the shape of the Δh-Δc relationship to stand density, stand age and water deficit. The shape of the Δh-Δc relationship shifted from linear with a moderate slope in open-grown stands to concave saturating with an initial steep slope in closed stands. Maximum height growth was found to follow a typical mono-modal response to stand age. In open-grown stands, increasing summer soil water deficit was found to decrease height growth relative to radial growth, suggesting hydraulic constraints on height growth. A similar pattern was found in closed stands, the magnitude of the effect however lowering from suppressed to dominant trees. We highlight the high phenotypic plasticity of growth in sessile oak trees that further adapt their allocation scheme to their environment. Stand density and tree social status were major drivers of growth allocation variations, while water stress had a detrimental effect on height in the

  15. Limited Pollen Dispersal Contributes to Population Genetic Structure but Not Local Adaptation in Quercus oleoides Forests of Costa Rica.

    Directory of Open Access Journals (Sweden)

    Nicholas John Deacon

    Full Text Available Quercus oleoides Cham. and Schlect., tropical live oak, is a species of conservation importance in its southern range limit of northwestern Costa Rica. It occurs in high-density stands across a fragmented landscape spanning a contrasting elevation and precipitation gradient. We examined genetic diversity and spatial genetic structure in this geographically isolated and genetically distinct population. We characterized population genetic diversity at 11 nuclear microsatellite loci in 260 individuals from 13 sites. We monitored flowering time at 10 sites, and characterized the local environment in order to compare observed spatial genetic structure to hypotheses of isolation-by-distance and isolation-by-environment. Finally, we quantified pollen dispersal distances and tested for local adaptation through a reciprocal transplant experiment in order to experimentally address these hypotheses.High genetic diversity is maintained in the population and the genetic variation is significantly structured among sampled sites. We identified 5 distinct genetic clusters and average pollen dispersal predominately occurred over short distances. Differences among sites in flowering phenology and environmental factors, however, were not strictly associated with genetic differentiation. Growth and survival of upland and lowland progeny in their native and foreign environments was expected to exhibit evidence of local adaptation due to the more extreme dry season in the lowlands. Seedlings planted in the lowland garden experienced much higher mortality than seedlings in the upland garden, but we did not identify evidence for local adaptation.Overall, this study indicates that the Costa Rican Q. oleoides population has a rich population genetic history. Despite environmental heterogeneity and habitat fragmentation, isolation-by-distance and isolation-by-environment alone do not explain spatial genetic structure. These results add to studies of genetic structure by

  16. The importance of drought-pathogen interactions in driving oak mortality events in the Ozark Border Region

    Science.gov (United States)

    Wood, Jeffrey D.; Knapp, Benjamin O.; Muzika, Rose-Marie; Stambaugh, Michael C.; Gu, Lianhong

    2018-01-01

    Forests are expected to become more vulnerable to drought-induced tree mortality owing to rising temperatures and changing precipitation patterns that amplify drought lethality. There is a crucial knowledge gap regarding drought-pathogen interactions and their effects on tree mortality. The objectives of this research were to examine whether stand dynamics and ‘background’ mortality rates were affected by a severe drought in 2012; and to evaluate the importance of drought-pathogen interactions within the context of a mortality event that killed 10.0% and 26.5% of white (Quercus alba L.) and black (Q. velutina Lam.) oak stems, respectively, in a single year. We synthesized (i) forest inventory data (24 years), (ii) 11 years of ecosystem flux data with supporting biological data including predawn leaf water potential and annual forest inventories, (iii) tree-ring analyses of individual white oaks that were alive and ones that died in 2013, and (iv) documentation of a pathogen infection. This forest displayed stand dynamics consistent with expected patterns of decreasing tree density and increasing basal area. Continued basal area growth outpaced mortality implying a net accumulation of live biomass, which was supported by eddy covariance ecosystem carbon flux observations. Individual white and black oaks that died in 2013 displayed historically lower growth with the majority of dead trees exhibiting Biscogniauxia cankers. Our observations point to the importance of event-based oak mortality and that drought-Biscogniauxia interactions are important in shaping oak stand dynamics in this region. Although forest function has not been significantly impaired, these drought-pathogen interactions could amplify mortality under future climate conditions and thus warrant further investigation.

  17. Oak Ridge National Laboratory Review

    Energy Technology Data Exchange (ETDEWEB)

    Krause, C.; Pearce, J.; Zucker, A. (eds.)

    1992-01-01

    This report presents brief descriptions of the following programs at Oak Ridge National Laboratory: The effects of pollution and climate change on forests; automation to improve the safety and efficiency of rearming battle tanks; new technologies for DNA sequencing; ORNL probes the human genome; ORNL as a supercomputer research center; paving the way to superconcrete made with polystyrene; a new look at supercritical water used in waste treatment; and small mammals as environmental monitors.

  18. Oak management for wood products

    Science.gov (United States)

    Roger Barlow

    1971-01-01

    A method is presented for analyzing oak management alternatives through comparisons of the present value of the net cash flow produced. Even-aged management without age-class regulation returned $72.60 of present value over a 40-year period. In the next 40 years the only expenses reduce the present value to $72.43. To regulate this stand into a forest with an equal...

  19. Oak Ridge strategy accelerates cleanup

    International Nuclear Information System (INIS)

    Garland, S.B. II; Boston, H.L.

    1996-01-01

    The strategy of the Oak Ridge Reservation Environmental Restoration Program is to accelerate the transition from characterization to remediation by making decisions at the watershed scale based on recommended land uses and historical data. Since the primary means of contaminant transport is via shallow groundwater to surface water, grouping contaminated sites by watersheds for characterization, decision-making, and remediation allows consistency and appropriateness in remedy selection. It also results in cost and schedule savings

  20. Blue ocean strategy.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2004-10-01

    Despite a long-term decline in the circus industry, Cirque du Soleil profitably increased revenue 22-fold over the last ten years by reinventing the circus. Rather than competing within the confines of the existing industry or trying to steal customers from rivals, Cirque developed uncontested market space that made the competition irrelevant. Cirque created what the authors call a blue ocean, a previously unknown market space. In blue oceans, demand is created rather than fought over. There is ample opportunity for growth that is both profitable and rapid. In red oceans--that is, in all the industries already existing--companies compete by grabbing for a greater share of limited demand. As the market space gets more crowded, prospects for profits and growth decline. Products turn into commodities, and increasing competition turns the water bloody. There are two ways to create blue oceans. One is to launch completely new industries, as eBay did with online auctions. But it's much more common for a blue ocean to be created from within a red ocean when a company expands the boundaries of an existing industry. In studying more than 150 blue ocean creations in over 30 industries, the authors observed that the traditional units of strategic analysis--company and industry--are of limited use in explaining how and why blue oceans are created. The most appropriate unit of analysis is the strategic move, the set of managerial actions and decisions involved in making a major market-creating business offering. Creating blue oceans builds brands. So powerful is blue ocean strategy, in fact, that a blue ocean strategic move can create brand equity that lasts for decades.