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Wyszukujesz frazę "Abies" wg kryterium: Temat


Tytuł:
Monitoring of xylem formation in Picea abies under drought stress influence
Autorzy:
Gryc, V.
Hacura, J.
Vavrcik, H.
Urban, J.
Gebauer, R.
Powiązania:
https://bibliotekanauki.pl/articles/41506.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
monitoring
xylem formation
Norway spruce
Picea abies
drought stress
Opis:
The effect of drought stress on regular cambium activity and wood formation in stems of two different clones of Norway spruce (Picea abies (L.) Karst.) was investigated. Tissue samples were taken during the growing season from May to September 2010. Artificial drought stress, induced by long-term sheltering of the soil, was significantly manifested in clone 15. In the stressed individual, the period of cambium activity was shorter, the total number of formed cells was lower and the resulting tree ring was narrower. The number of cells in the phases of postcambial growth and secondary cell wall formation was significantly lower in comparison to the control tree. The tracheid lignification process was slower in the tree stressed by water deficit and the first mature tracheids were observed later. On the other hand, in clone 18 probably genetic dispositions played an important role as no considerable deviations in the cambium activity and new wood cells production were observed. Fitting xylem increments to the Gompertz function showed that the period of the most intensive cell formation was at the turn of June and July and the maximum daily production of new cells was higher in non-stressed individuals than in the stressed ones. The results of the experiment lead us to the conclusion that drought stress can significantly affect the cambium activity of some clones, the differentiation process of anatomical elements, and thus also the resulting tree ring width.
Źródło:
Dendrobiology; 2012, 67
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The radial growth-competition relationship in Picea abies stands affected by windfall
Autorzy:
Badea, O.
Dumitru, I.
Cojocia, C.
Popa, I.
Powiązania:
https://bibliotekanauki.pl/articles/41406.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Norway spruce
stand
Picea abies
windfall
risk factor
Opis:
Actual status of mountain forests especialy, of Norway spruce (Picea abies Karst. (L)) stands is a result of combined action between forest management measures and biotic and abiotic risk factors. In this context, tree growth dynamics is a result of multifactor interaction (competition, disturbance, management practice, climate etc.). Wind damage affect the stand structure and normal ecosystem functions including the relationship between individual tree growth and competition processes. Though, it is recorded a diminishing of productive capacity for affected stands as well as a significant diameter increment for remaining standing trees. The correlation between tree growth (cumulate basal area increment in the last 10 years) and competition (Hegyi and Schutz competition indices) was analysed in stands with different windfall intensity. No relationship between tree growth and competition was observed in highly affected stands. Schutz competition index explains better individual tree growth comparing with Hegyi index in low or no-affected stand by windthrow. The variability of the basal area increment (lnΔɡ10), explained by competition indices, is rather low (<2%) in the stand that had been highly affected by windfall, regardless of the selected competition index. Thus, significant reduction of the stand density related to number of trees (low density), as a consequence of high intensity windfalls, crown competition has a very small influence on the basal area increment comparing with situations met in low (high density) and moderate (medium density) affected stands.
Źródło:
Dendrobiology; 2015, 73
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spruce tree-ring proxy signals during cold and warm periods
Autorzy:
Esper, Jan
Carnelli, Adriana L.
Kamenik, Christian
Filot, Marc
Leuenberger, Markus
Treydte, Kerstin
Powiązania:
https://bibliotekanauki.pl/articles/956991.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
stable isotopes
maximum latewood density
reconstruction model
picea abies
engadin
alps
Opis:
The strength and temporal rigidity of climate signals are important characteristics of proxy data used to reconstruct climate variability over pre-instrumental periods. Here, we assess the performance of different tree-ring proxies, including ring width, maximum latewood density, δ13C, and δ18O, during exceptional cold (1800–1850) and warm periods (1946–2000). The analysis was conducted at a spruce (Picea abies) timberline site in the Swiss Alps in proximity to long homogenized instrumental records to support calibration tests against early temperature and precipitation data. In this cold environment, tree-ring width, maximum latewood density, and δ18O are mainly controlled by temperature variations. δ13C is influenced by various factors including temperature, precipitation, sunshine, and relative humidity. When comparing the response patterns during cold and warm periods, ring width and maximum latewood density revealed temporally stable temperature signals. In contrast, the association between the stable isotopes and climate changed considerably between the early 19th and late 20th centuries. The temperature signal in δ18O was stronger during the recent warm period, whereas the opposite is true for δ13C. In δ13C, the temperature signal weakened from the early 19th to the late 20th centuries, but an (inverse) precipitation signal evolved indicating that soil moisture conditions additionally limited recent carbon isotope ratios. An attempt to combine the tree-ring proxies in a multiple regression model did not substantially improve the strength of the dominating temperature signal retained in the latewood density data as this proxy already explained a significant fraction of summer temperature variability. Our findings underscore the importance of split calibration/verification approaches including cold and warm periods, and challenge transfer models based on only late 20th century observational data.
Źródło:
Dendrobiology; 2017, 77; 3-18
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flowering and cone bearing of Picea abies grafts in second-generation seed orchards
Autorzy:
Misiorny, A
Chalupka, W.
Powiązania:
https://bibliotekanauki.pl/articles/41542.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Norway spruce
Picea abies
cone yield
seed production
flowering
seed orchard
Opis:
In 2004, abundant flowering of Norway spruce (Picea abies (L.) Karst.) was observed in two second- generation seed orchards: (1) ‘Outbreeding’, promoting crossing between clones of five geographically distant populations; and (2) ‘Kolonowskie’, restoring a population whose offspring exists only in an international experiment (IUFRO 1964/1968). In bothseed orchards, female strobili were produced by 91.3% and 91.7% of clones, represented by 64.1% and 55.5% of grafts, respectively, and statistically significant differences between clones were found in the number of mature cones. In the case of the seed orchard ‘Outbreeding’, the number of mature cones in individual clones was significantly correlated with latitude of the origin of maternal populations (r = 0.8826, p = 0.0470). The majority (95%) of cones in seed orchards ‘Outbreeding’ and ‘Kolonowskie’ were produced by only 28.2% and 38.5% of all clones, and 21.4% and 25.7% of all grafts, respectively. These data attest to a disparity between the level of genetic diversity in seed orchard progeny resulting from the observed numbers of cone-bearing clones and grafts and the genetic diversity expected from the actual participation of clones and grafts in seed orchard composition. The estimated seed production per 1 ha of seed orchard area in 2004 reached 21.05 kg for ‘Outbreeding’ and 21.72 kg for ‘Kolonowskie’.
Źródło:
Dendrobiology; 2006, 56; 51-59
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The spatial pattern and microsites requirements of Abies alba natural regeneration in the Karkonosze Mountains
Autorzy:
Szymura, T H
Dunajski, A.
Aman, I.
Makowski, M.
Szymura, M.
Powiązania:
https://bibliotekanauki.pl/articles/41501.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Karkonosze Mountains
Norway spruce
Picea abies
silver fir
Abies alba
microsite requirement
natural regeneration
age structure
browsing
safe site
seedling dispersal
spatial distribution
Opis:
Progeny of four adult silver firs, which were an admixture in Norway spruce (Picea abies) stand was, analyzed. The study was done in lower mountain zone of the Karkonosze (Giant Mts.) National Park (SW Poland). The seedlings occurred in two clumps related to the position of adult trees, whereas spatial pattern of the seedlings inside each clump was random. The seedlings were spaced mainly in distances 5–25 from the nearest adult tree. The maximal distance was up to 50 m. Most seedlings were established in accordance with main wind directions. Also, in these directions seedlings were more distant from adult trees than in other directions. The seedlings grew in better light environment (12% of PPFD) than average (9,6% PPFD). This effect was statistically significant. The height increment of the seedlings was low and was not correlated with light conditions. Similarly, there was not any correlation between the apical dominance ratio and light. The lack of this correspondence we attributed to browsing. The silver fir seedlings were significantly underrepresented in patches of Vaccinium myrtillus, on raw needles, under crown of adult trees and in concave micro-relief form. The underrepresentation in the places covered by canopy and in patches of bilberry we related to the indirect effect of continuous browsing, which leads to higher seedlings mortality in more shaded places and sites of stronger competition between forest floor vegetation and silver fir seedlings.
Źródło:
Dendrobiology; 2007, 58; 51-57
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A 434-year tree-ring chronology of spruce (Picea abies) with indications of Estonian precipitation
Autorzy:
Laanelaid, A.
Helama, S.
Eckstein, D.
Powiązania:
https://bibliotekanauki.pl/articles/41704.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
dendrochronology
conifer
dendroclimatology
drought
Norway spruce
Picea abies
tree ring
Estonia
Opis:
In this study, an Estonian tree-ring network of Norway spruce (Picea abies (L.) H.Karst.), originating from both living trees and dead wood of construction wood, was used for determining the growth variations over the past 350 years (AD 1657–2009). Regional curve standardization was used to remove the non-climatic growth variations from the individual tree-ring series prior to dendroclimatic analyses to focus on the low-frequency (long-term and -period) growth variations. Previously, the chronology has been shown to correlate markedly well with Estonian precipitation history. Here we further detail this dendroclimatic connection. Correlations between the Estonian precipitation and treerings improved systematically with both the number of meteorological stations included and with the documented technical advances in the network of instrumental weather observations. The observed June precipiation explains roughly 20 percent of the tree-ring variance over the period when the network of weather observations is densest (1946–2009). On decadal and longer scales, the June precipitation explains higher portion of tree-ring variance, roughly 50 percent, over the full instrumental era (1866–2009). Comparison with previously published and similarly standardized tree-ring chronology from south-eastern Finland, based on Scots pine tree-rings, showed that the two chronologies exhibit several coinciding periods of ameliorated and deteriorated growth.
Źródło:
Dendrobiology; 2015, 73
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Accelerated and natural ageing processes change the properties of plasma membrane in Norway spruce (Picea abies (L.) Karst.) seeds during storage
Autorzy:
Nowakowska, J
Rakowski, K.
Powiązania:
https://bibliotekanauki.pl/articles/41613.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
plasma membrane
Norway spruce
natural aging process
Picea abies
vitality
vigor
storage
seed
Opis:
The present study examines the mechanism of natural and accelerated ageing processes in Norway spruce (Picea abies [L.] Karst.) seeds stored at low temperature for one (control) and eight years. The analyses of vitality, electrolyte leakage, protein composition and activity of the proton-pump ATPase (P-ATPase, EC.3.6.1.35) in plasma membrane of Norway spruce seeds have been investigated. Seeds collected in 1999 from northeastern Poland have been treated with accelerated ageing method and compared to the seeds of the same provenance, collected in 1992 (control). The vigor and the vitality of the Norway spruce seeds depend on the age of seeds. After 6 days of experiment both samples of seeds (artificially aged seeds and control) expressed the same percentage of germination and similar electrolyte leakage. Analysis of protein composition in the extracts showed an increased amount of some low molecular-weight proteins in artificially and naturally aged seeds compared to the control. Our results indicate similar level of P-ATPase activity in natural, artificially aged and control seeds. This suggests that natural ageing process can involve changes in plasma membrane protein composition but does not affect the P-ATPase activity.
Źródło:
Dendrobiology; 2002, 47 Supplement
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamics and structure of mountain autochthonous spruce-beech forests: impact of hilltop phenomenon, air pollutants and climate
Autorzy:
Králíček, Ivo
Vacek, Zdeněk
Vacek, Stanislav
Remeš, Jiří
Bulušek, Daniel
Král, Jan
Štefančík, Igor
Putalová, Tereza
Powiązania:
https://bibliotekanauki.pl/articles/957043.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
natural forests
biodiversity
stress factors
fagus sylvatica
picea abies
orlické hory mts
Opis:
Mountain forests are strongly influenced by the extreme climate, short growing season and stress from environmental pollution and lower fertility of soils. The paper analyses the effect of the environment (climate and air pollutants) on the structure, production and dynamics of autochthonous spruce-beech forest stands in protected areas in the summit parts of the Orlické hory Mts., Czech Republic. The spatial pattern of tree layer was random in lower parts below the summit and aggregated under the hilltop phenomenon on an extreme edaphic site, such as aggregated horizontal structure of natural regeneration. In most cases, the relationship between the spatial pattern of tree layer and natural regeneration was significantly negative (α = 0.05) at a smaller distance (from stem to 0.6–6.1 m) except stands under the strong hilltop phenomenon (positive effect to 2.1 m). The stand density ranged from 440 to 760 trees ha–1 and the number of natural regeneration was 4 584–6 360 recruits ha–1. Dominant height decreased with increasing influence of hilltop phenomenon (P < 0.001). The volume of live trees was 239–536 m3 ha–1. The radial growth of dominant European beech (Fagus sylvatica L.) indicated a relatively balanced long-term trend of tree-ring width in 1900–2014, but diameter increment of admixed Norway spruce (Picea abies /L./ Karst.) after 1978 significantly decreased (P < 0.001) and since 1998 radial increment in spruce distinctly increased. Radial growth of spruce was significantly negatively correlated with mean SO2 and NOX concentrations, especially in April (P < 0.001), but there was no effect on radial growth of beech. Air pollution had a significantly higher negative effect on radial growth of spruce on the hilltop compared to the lower part of the hill. The correlation between radial increment and temperature was stronger than in precipitation for both species in mountain areas compared to lowlands. The hilltop phenomenon significantly influenced the structure of spruce-beech mountain forests. The lowest dynamics was observed in stands in middle slope parts compared to summit parts of the hill.
Źródło:
Dendrobiology; 2017, 77; 119-137
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth characteristics and needle structure in some interspecific hybrids of Abies cephalonica Loud
Autorzy:
Kormutak, A.
Galgoci, M.
Manka, P.
Bolecek, P.
Camek, V.
Vookova, B.
Gomory, D.
Powiązania:
https://bibliotekanauki.pl/articles/41685.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
plant growth
needle structure
interspecific hybrid
Abies cephalonica
Greek fir
cross hybrid
plant anatomy
Opis:
The height growth dynamics of three interspecific crosses with Greek fir (Abies cephalonica Loud.) acting as mother and a control variant from self-pollination were followed throughout a period of 30 years. The hybrid combination A. cephalonica × A. nordmanniana exhibited enhanced growth relative to the selfed control at stage of 4-year old seedlings already, whereas the hybrid A. cephalonica × A. alba only at stage of 9-year old saplings. At age of 30, the heterotic growth persisted only in the latter, the hybrid A. cephalonica × A.nordmanniana was comparable in height growth parameters with a selfed control. The interspecific cross A. cephalonica × A. numidica was remarkable by its accelerated growth during early stages of the development. At age of 4 years it has surpassed in height growth both A. cephalonica × A. alba and control but has declined profoundly during subsequent stages of its development. A conspicuous feature of the hybrid needle anatomy were abundant resin canals and reduced size of some anatomical traits of its needles. In spite of variable growth potentials, all the three interspecific hybrids are recommended for planting in Slovakia, especially at densely polluted areas where domestic silver fir cannot withstand emission pressure.
Źródło:
Dendrobiology; 2015, 73
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Changes in starch distribution within an embryonic shoot of Norway spruce (Picea abies (L.) Karst.) before resumption of mitotic activity
Autorzy:
Guzicka, M.
Powiązania:
https://bibliotekanauki.pl/articles/41758.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Norway spruce
temperature
embryonic shoot
Feulgen reaction
change
Picea abies
starch distribution
mitotic activity
Opis:
The above results supplemented earlier research on the structure and development of Norway spruce embryonic shoots and focuses on changes in starch distribution in winter and early spring. Starch accumulation and mobilization is characteristic of cells that play an important role in morphogenesis. The observed starch distribution within an embryonic shoot suggests that starch indicates the places of future mitotic and morphogenetic activities of the developing shoot. Changes of the rate of starch accumulation in a bud are affected by temperature. This study showed that especially important are the course of temperature fluctuations.
Źródło:
Dendrobiology; 2001, 46
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Abies somatic embryogenesis and its application
Autorzy:
Vookova, B.
Kormutak, A.
Powiązania:
https://bibliotekanauki.pl/articles/41461.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Abies
fir
protein analysis
chlorophyll content
macroelement
microelement
incompatible crossing
somatic embryogenesis
application
Opis:
This paper provides results of somatic embryogenesis study in our laboratory. General description of somatic embryogenesis (SE) induction, maturation of somatic embryos and plantlets regeneration of the Abies species, followed by a comparisons of some characteristics of zygotic and somatic embryos, seedlings and emblings (somatic seedlings). Own results are supplemented with some literature data. Also aplication of SE for improving of plantlet regeneration of elite fir trees from Dobroč primeval is described as well as initiation of the SE from seeds of incompatible crossings of firs where zygotic embryos abort usually several weeks after pollination
Źródło:
Dendrobiology; 2014, 71
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Breeding programmes of Norway spruce Picea abies (L.) Karst. in the Czech Republic
Autorzy:
Hynek, V
Powiązania:
https://bibliotekanauki.pl/articles/41747.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Czech Republic
forest tree
Norway spruce
Picea abies
breeding programme
altitudinal vegetation zone
Opis:
In the Czech Republic, Norway spruce has a natural representation in all forest altitudinal vegetation zones, in some of which (FAVZ 1, 2 and 9), however, it is scarce. The three basic climatic ecotypes of spruce identified in the Czech territory, i.e. an upland ecotype, a higher elevation ecotype and a mountain ecotype, can be characterised on the basis of the forest altitudinal vegetation zones of their origin. The paper presents the breeding work completed so far and all the breeding programmes implemented for Norway spruce, including projects worked out for the Krkonoše National Park.
Źródło:
Dendrobiology; 2004, 51 Supplement
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Embryogenic callus induction and differentiation in silver fir (Abies alba Mill.) tissue cultures
Autorzy:
Nawrot-Chorabik, K
Powiązania:
https://bibliotekanauki.pl/articles/41643.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
silver fir
Abies alba
tissue culture
embryogenic suspensor mass
somatic embryogenesis
callus induction
differentiation
Opis:
The research was conducted on explants of silver fir (Abies alba Mill.) deriving from several forest districts in southern Poland. The study encompassed the influence of the origin of plant material, type of explants, kind of substances used for explants sterilization, PPM and the type of medium on the ability to form embryogenic callus and to develop somatic embryos in silver fir explants. From the plant material collected in three sites, 57 clones were obtained from mature zygotic embryos; this produced an embryogenesis frequency of 6%. Embryogenic callus was obtained with a diameter of 65–70 mm depending on the material origin. The best medium for development of callus inducted on embryos isolated from mature silver fir seeds was the SH medium. Somatic embryos were formed in a globular stadium (24 pieces) on this medium. The 10% solution of NaOCl (used for 15 minutes) turned out to be the most effective substance for seed sterilization.
Źródło:
Dendrobiology; 2008, 59; 31-40
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Near-natural methods of forest regeneration
Autorzy:
Mauer, O
Powiązania:
https://bibliotekanauki.pl/articles/41324.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Norway spruce
Picea abies
artificial regeneration
plantation
mountain forest stand
forest regeneration
regeneration method
technological procedure
Opis:
The study examines the factors involved in the successful artificial regeneration of Norway spruce Picea abies (L.) Karst. by plantation or sowing in wood left behind in mountain forest stands. The issues studied are as follows: regeneration in stumps,trunks and disks (logs); regeneration in wood at various stages of decomposition; regeneration under the stand canopy and on clearings. The work brings a description of technological procedures to ensure success of this regeneration method.
Źródło:
Dendrobiology; 2004, 51 Supplement
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Species conversion of spruce stands in the Wisła Forest District
Autorzy:
Skrzyszewski, J
Skrzyszewska, K.
Powiązania:
https://bibliotekanauki.pl/articles/41743.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Wisla Forest District
spruce
Picea abies
Istebna spruce
seed stand
spruce stand
forest tree
species conversion
Opis:
The paper provides some guidelines on the choice of the target species compositions for plantations that would replace monocultural spruce stands growing on the sites of the Silesian Beskid Mts. Part of the guidelines relates to the rules governing the sequence in which the monocultures will be converted into mixed stands. It is suggested that those rules should be combined with the principles of the establishment of progenyplantations. The seed stands of the Istebna spruce are experimentally divided into four categories according to their abilityto perform the function of a seed stand. The following features of the stands are analysed: vitality, density, stage of regeneration, protective and cultural functions. The paper contains also an outline of the methods of species conversion and the relevant references.
Źródło:
Dendrobiology; 2004, 51 Supplement
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł

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