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1.
• Background
Production of seedlings, especially in containers, requires simultaneous germination and emergence. Mechanical scarification often speeds up the growth of embryo axes, increases the percentage of germinating seeds and seedling emergence. Cutting off the distal ends of cotyledons is a mechanical scarification technique sometimes used in the container production of oak seedlings. However the consequences of this procedure for seedling development are little known. We wanted to determine these effects on development and metabolic changes of pedunculate oak (Quercus robur L.) seedlings. 相似文献2.
Introduction
We examined the functional relationship between seed size and seedling performance in the valley oak (Quercus lobata Née) by means of a 13-year common garden experiment. 相似文献3.
Andrea Cutini Paolo Bongi Francesco Chianucci Nives Pagon Stefano Grignolio Emilio Amorini Marco Apollonio 《Annals of Forest Science》2011,68(4):667-674
Introduction
Roe deer (Capreolus capreolus) browsing pressure on vegetative regeneration of Turkey oak (Quercus cerris) and chestnut (Castanea sativa) and roe deer use of coppiced areas were investigated. 相似文献4.
Fall fertilization of Holm oak affects N and P dynamics,root growth potential,and post-planting phenology and growth 总被引：2，自引：0，他引：2
Juan A. Oliet José M. Salazar Rafael Villar Eduardo Robredo Fernando Valladares 《Annals of Forest Science》2011,68(3):647-656
• Introduction
For Holm oak (Quercus ilex L.), a flush growing species, nutrient loading during the growing season is difficult and can lead to a low nutrient status of the seedlings. To provide insights about Holm oak nutrient dynamics during fall in the nursery and subsequent planting performance, a factorial nursery experiment was conducted in a mild fall–winter area testing the effects of timing of fertilization (early and late fall) and rate (two doses of a NPK fertilizer that applied 28 and 56 mg N per seedling), followed by an experimental plantation. 相似文献5.
• Background and purpose
A complex interplay between biotic and abiotic factors is believed to be responsible for several oak declines in pedunculate oak (Quercus robur L.). This study aims to clarify the temporal process of oak declines, as well as identifying individual tree and environmental variables that affects growth rate and that may increase the risk of mortality. The study was performed in southern Sweden at three sites. 相似文献6.
• Background
The Holm oak (Quercus ilex ssp. ballota [Desf.] Samp.) is an evergreen tree widely distributed in the western Mediterranean Basin. Forest restoration programs using this species have enjoyed only limited success, and knowledge concerning the effect of fertilization on plant quality and post-transplantation response is sparse. 相似文献7.
In this study, the supply and input–output balances of phosphorus (P) were investigated for a 10-year-period at 85 long-term
monitoring sites in German forest ecosystems under the European Level II programme. These sites encompass 23 European beech
(Fagus sylvatica L.) stands, 9 oak stands comprised of common oak (Quercus robur L.) and/or sessile oak (Quercus petraea Liebl.), 20 Scots pine (Pinus sylvestris L.) and 33 Norway spruce (Picea abies H.Karst.) stands. We quantified P concentrations in needles and leaves, P inputs from the atmosphere, P outputs through leaching
and harvesting, and total P in the soil and humus layers. The P concentrations in European beech leaves from two sites (>1 mg P g−1 dry weight), and in Norway spruce needles from four sites (>1.2 mg P g−1 dry weight), were deficient over several years. In contrast, the oak and Scots pine sites were well supplied with P. When
P removal through harvesting was disregarded, P balances were positive or stable (median 0.21 kg P ha−1 a−1). With harvesting, balances were mostly negative (median −0.35 kg P ha−1 a−1), with long-term P removal from the forest ecosystems. 相似文献
8.
Belkheir Dehane Carmen Hernando Mercedes Guijarro Javier Madrigal 《Annals of Forest Science》2017,74(3):60
Key message
The high flammability of some companion species in Quercus suber forests, estimated in laboratory tests, could potentially generate an increase in fire vulnerability and in fire risk.Context
Recurrent wildfire is one of the main causes of forest degradation, especially in the Mediterranean region. Increased fire frequency and severity due to global change could reduce the natural resilience of cork oak to wildfire in the future. Hence, it is important to evaluate the flammability of companion species in cork oak forests in the particularly dry bioclimatic conditions of North Africa.Aims
This study aimed to assess and compare flammability parameters at laboratory scale among ten companion frequent species in cork oak forests.Methods
Fuel samples were collected in a cork oak (Quercus suber L) forest in the southern part of the mountains of Tlemcen (Western Algeria). A series of flammability tests were carried out using a Mass Loss Calorimeter device (FTT ®). A cluster analysis to classify flammability of the selected species was conducted using the K-means algorithm.Results
The results revealed differences in the four flammability parameters (ignitability, sustainability, combustibility and consumability), in both fresh and dried fine fuel samples from Quercus suber, Pinus halepensis, Quercus ilex, Quercus faginea, Erica arborea, Arbutus unedo, Pistacia lentiscus, Calicotome spinosa, Juniperus oxycedrus and Tetraclinis articulata. Application of the K-means clustering algorithm showed that C. spinosa, T. articulata, J. oxycedrus and P. halepensis are highly flammable because of their high combustibility and sustainability.Conclusion
The findings identify species that could potentially increase the vulnerability of cork oak forests to forest fires.9.
• Objective
The objective of the research was to develop a generalized height–diameter model for Quercus suber L. in Portugal, which can be applied both to undebarked and debarked trees, with diameter at breast height over cork larger than 2.5 cm. 相似文献10.
M. C. Rodríguez‐Molina L. M. Torres‐Vila A. Blanco‐Santos E. J. Palo Núñez E. Torres‐Álvarez 《Forest Pathology》2002,32(6):365-372
The emergence and survival of pregerminated holm oak (Quercus ilex) and cork oak (Quercus suber) acorns from two ecologically different dehesas (Mediterranean open woodlands) were studied in two soils from these stands naturally infected with Phytophthora cinnamomi, and in the same soils previously sterilized in the autoclave. Phytophthora cinnamomi was consistently isolated from the radicles of all unemerged and all emerged but dead seedlings from the unsterilized substrates. Seedlings of holm oak were more susceptible to P. cinnamomi than those of cork oak. Mortality of holm oak seedlings was significantly different depending only on soil treatment (sterilized or unsterilized), and it was 100% in unsterilized soils, independent of acorn provenance and soil origin. Mortality of cork oak seedlings was significantly different depending on the acorn origin and soil treatment, and on the interactions acorn origin × soil origin and soil origin × soil treatment. The demonstrated high susceptibility of holm and cork oak young seedlings to P. cinnamomi could be a limiting factor in Mediterranean open woodlands (dehesas) not only in natural regeneration processes but also when reforestation by direct sowing is implemented. 相似文献
11.
Oak (Quercus robur) powdery mildew is a common and damaging fungal disease. In a local survey at Reading, UK, oak powdery mildew was common on trees of all height classes but was most common on trees of 3–9 m. A variety of other fungal species were commonly found growing in association with oak powdery mildew colonies. The abundance of such fungi was estimated through stratified sample surveys for 2.5 years. The taxa most commonly associated with oak powdery mildew were Acremonium sp., Trichoderma sp., Ampelomyces/Phoma sp. and Leptosphaerulina australis. Nearly 90% of mildew colonies were associated with L. australis, which is not generally considered as a mycoparasite or antagonist, in contrast with the other three fungi. Abundance varied between June and October surveys. Acremonium sp. abundance was greater in summer samplings, whereas L. australis and Trichoderma sp. abundances were greater in autumn samplings. Ampelomyces/Phoma sp. was never observed in the absence of powdery mildew. Relationships between the mildew‐associated fungi and oak powdery mildew appeared curved and differed significantly between sampling years. L. australis was positively correlated with the other three associated fungi studied when powdery mildew was also present . The variety and high population densities of the mildew‐associated fungi suggest that they may be important in determining the final density of oak mildew and the damage caused by it. 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(1-4):9-16
The influence of tree species and soil properties on leaf litterfall concentrations and fluxes of elements were studied in three mixed deciduous forest stands. Leaf litterfall fluxes of sixteen elements were measured during autumn defoliation in 100 to 150 yr old individuals of Fagus sylvatica L., Quercus robur L., Carpinus betulus L., Tilia cordata Mill, and Acer platanoides L. Compared to throughfall and precipitation, leaf litterfall dominated the flux of P, Ca, Mn, N and Mg (in decreasing order) to the soil below the tree canopies. For K and especially S and Na, however, the importance of leaf litterfall input to the total fluxes was small. Fluxes and especially concentrations of Ca, Mg, K, P and partly N were positively related to base saturation of the soil, while Mn was negatively related due to a higher mobilization rate and plant uptake of this element on acid soils. Litterfall fluxes for C. betulus were strongly positively influenced by base saturation and fluxes were usually higher than for F. sylvatica and Q. robur at the richest site. Quercus robur had often the lowest fluxes, especially of Ca and Mg. Tilia cordata had the highest leaf litter concentrations in twelve of the sixteen elements, and the highest fluxes particularly of N and K. Acer platanoides had the highest or among the highest concentrations and fluxes of Ca, Zn and Mn. The concentration of Al in C. betulus leaf litterfall, was about five times higher than in all other tree species at all sites. 相似文献
13.
Syamak Hanifeh Doustmorad Zafari Mohammad Javad Soleimani Abbasali Ravanlou 《Forest Pathology》2019,49(1)
During spring and summer of 2016, dieback symptoms including blights of leaves, twigs, and acorns were observed on current year shoots of Quercus infectoria in the Zagros oak forests of Iran. The fungus isolated from damaged tissues was identified as Discula quercina based on both morphological characteristics and ITS sequencing. To fulfil the Koch's postulates, a representative isolate was inoculated onto shoots of Q. infectoria and Quercus libani in both laboratory and forest conditions. Responses of the two oak species to inoculation with D. quercina were examined under laboratory and forest conditions in a completely randomized experiment. Discula quercina was clearly involved in oak dieback, and Q. infectoria was more susceptible than Q. libani to damage by the pathogen. This is the first record of the occurrence and pathogenicity of the fungus Discula quercina on Quercus infectoria. The fungus is considered as an emerging pathogen on oak trees in Zagros forests in Iran. Furthermore, the pathogenicity of the Discula quercina on Q. libani under laboratory and forest conditions increases the potential importance of this pathogen in Zagros forests. 相似文献
14.
António M. Jordão Jorge M. Ricardo-da-Silva Olga Laureano An Adams Jan Demyttenaere Roland Verhé Norbert De Kimpe 《Journal of Wood Science》2006,52(6):514-521
The purpose of this study was to investigate the sorption of selected volatile substances from oak wood-chip samples (Quercus pyrenaica Willd. and Quercus petraea L.) subjected to different toasting levels, namely, without toasting, with medium toasting, and with strong toasting, through
the use of solid-phase microextraction (SPME). The main volatile compounds identified as a function of the toasting level
and botanical species were furfural, hexanal, α-pinene, d-limonene, decanal, vitispirane, ethyl hexanoate, cis-3-methyl-γ-octalactone (“oak lactone” or “whisky lactone”), α-terpineol, p-xylene, and nonanal. Considering the data obtained from the toasted woods (medium and strong intensity) in comparison with
those of nontoasted woods, it can be pointed out that the average peak area and the number of compounds identified in the
gas chromatogram decreased during the toasting process. In general, regarding the compounds analyzed, quantitative differences
were found between the two oak wood species under study. High values of volatile compounds were found in Quercus pyrenaica oak wood chips. In addition, for the number of compounds identified in oak wood extracts and directly extracted from solid
oak wood chips by SPME, it is concluded that the best extraction process for volatile compounds from oak wood is the use of
oak wood-chip liquid extracts. 相似文献
15.
16.
Andrea Cutini Francesco Chianucci Roberta Chirichella Emanuela Donaggio Luca Mattioli Marco Apollonio 《Annals of Forest Science》2013,70(5):493-502
Context
Pulsed food resources may strongly affect the population dynamics of several consumer species, with consequences on the ecosystem. One of the most common pulsed resources is forest mast seeding.Aims
We analysed mast seeding in deciduous forests in a mountainous area of northern Apennines and its effect on population dynamics of wild boar (Sus scrofa L.).Methods
We performed a quantitative, 20-year analysis on annual seed production in Turkey oak (Quercus cerris L.), beech (Fagus sylvatica L.) and chestnut (Castanea sativa Mill.) forest stands using litter traps. The wild boar population density was estimated by means of drive censuses and hunting bag records. The role of other biotic (density of predators) and abiotic (climate) factors potentially affecting wild boar mortality was also investigated.Results
Turkey oak and chestnut showed high levels of seed production, whereas lower levels were found in beech. The pulsed resources of chestnut and Turkey oak positively affected piglet density. Analyses also highlighted the influence of snow cover and wolves on wild boar population dynamics.Conclusion
Wild boar can be considered a pulse rate species, the management of which can be improved by annual monitoring of seed production. 相似文献17.
Stephen H. Anderson Ranjith P. Udawatta Tshepiso Seobi Harold E. Garrett 《Agroforestry Systems》2009,75(1):5-16
Agroforestry practices are receiving increased attention in temperate zones due to their environmental and economic benefits.
To test the hypothesis that agroforestry buffers reduce runoff by increased infiltration, water use, and water storage; profile
water content and soil water infiltration were measured for a Putnam soil (fine, smectitic, mesic Vertic Albaqualf). The watershed
was under no-till management with a corn (Zea mays L.)-soybean (Glycine max L.) rotation since 1991. Agroforestry buffer strips, 4.5 m wide and 36.5 m apart, were planted with redtop (Agrostis gigantea Roth), brome (Bromus spp.), and birdsfoot trefoil (Lotus corniculatus L.). Pin oak (Quercus palustris Muenchh.), swamp white oak (Q. bicolor Willd.) and bur oak (Q. macrocarpa Michx.) trees were planted at 3-m intervals in the center of the agroforestry buffers in 1997. Ponded water infiltration
was measured in agroforestry and grass buffers and row crop areas. Water content in agroforestry and row crop areas at 5,
10, 20, and 40 cm depths were measured throughout the year. Quasi-steady infiltration rates were not different (P > 0.05) among the treatments. Agroforestry had lower soil water content than row crop areas (P < 0.05) during the growing season. Higher water content after the principal recharge event in the agroforestry treatment
was attributed to better infiltration through the root system. Results show that agroforestry buffer strips reduce soil water
content during critical times such as fallow periods, and increase water infiltration and water storage. Therefore, adoption
of agroforestry buffer practices may reduce runoff and soil loss from watersheds in row crop management. 相似文献
18.
Z. Von Igmndy 《Forest Pathology》1977,7(4):230-236
Volume loss in Turkey oak coppice due to Inonotus nidus-pici Pilat. Inonotus nidus-pici Pilat (order Aphyllophorales, family Mucronoporaceae) causes serious damage to stands of Turkey oak (Quercus cerris L.) in South West Europe. The decay it causes in the heartwood gives rise to considerable losses in volume. 相似文献
19.
Daniel C. Dey Martin A. Spetich Dale R. Weigel Paul S. Johnson David L. Graney John M. Kabrick 《New Forests》2009,37(2):123-135
Research on oak (Quercus L.) regeneration has generally consisted of small-scale studies of treatments designed to favor oak, including consideration
of site quality and topographic effects on oak regeneration. However, these experiments have not consistently factored in
broader-scale ecological differences found in the eastern United States. Oak regeneration experiments should be replicated
at appropriate ecological scales to address the similarities and differences in regeneration following prescribed silvicultural
treatments among ecological units. Patterns in oak regeneration can be better understood in an ecological context by considering
how oak species interact in the differing physical environments and are able to maintain dominance in changing complexes of
competing vegetation among the selected eco-units. Our understanding of oak regeneration response to specific silvicultural
practices and our ability to model regeneration is improved when we use replication, blocking, or factorial deployment of
relatively small-scale (0.5–1.0 ha) treatment plots within an ecological classification system. We present an example of this
approach to understanding oak regeneration dynamics in a synthesis of research to regenerate northern red oak (Quercus rubra L.) by underplanting shelterwoods in Arkansas, Missouri and Indiana. We summarize important considerations to guide the design
of future research in oak regeneration.
Paul S. Johnson and David L. Graney—Retired U.S. Forest Service scientists. 相似文献
20.
María Pasalodos-Tato Timo Pukkala Isabel Cañellas Mariola Sánchez-González 《Annals of Forest Science》2018,75(2):61