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EN
The objectives of this study are (i) to evaluate the suitability of wavelet analysis and spline functions when applied for analysing changes in the short- and long-term DBH radial increment in more than 120 years-old beech Fagus sylvatica L. and (ii) to analyse relationships between the defoliation and the DBH radial increment in beech. Sampling was carried out in the Świętokrzyski National Park (forest sub-districts: Święta Katarzyna, Święty Krzyż and Chełmowa Góra), where 40 old-growth beech trees were randomly selected for the radial increment investigations. It was found that: wavelet analysis allows a precise separation of fluctuations in the diameter increment in different time periods; knowledge of the short-term fluctuations in the diameter increment enables analysing the relationships between defoliation and the DBH radial increment even in the case of insignificant variation in defoliation levels; the long-term trend in the diameter increment, when determined by the spline functions, is not always correlated with the defoliation level.
EN
The objectives of this study are (i) by using selected parametric models and the kernel density estimator to compare the accuracy of approximation of the empirical DBH distributions in stands of different vertical structure as well as the approximation accuracy in the empirical DBH data sets characterised by either average, or small or large differences in the number of DBHs in the neighbouring DBH classes, and (ii) to assess the significance of differences between the selected parametric models and the kernel density estimator. Sampling was carried out in the Świętokrzyski National Park (forest sub-districts: Święta Katarzyna and Święty Krzyż). In the stands of different vertical structure the irregular DBH empirical distributions require reducing the bandwidth of the kernel density estimator. In one-storied, two-storied and selection stands one should employ parametric models, using the kernel density estimator only for the preliminary approximations. However, when approximating the empirical DBH distributions in many-storied stands the kernel density estimation can be much more useful.
EN
The relative crown length, needle loss, and vitality of fir trees of older (above 160 years of age) and younger (from about 70 to about 130 years, with single trees up to 160 years of age) generations were significantly correlated with the current 10 year, (1985-1994), radial increment at breast height. In the case of trees of the younger generation the type of tree-top and the degree of crown deformation were also significantly correlated with the radial increment at breast height. The best growing fir trees of the younger generation were characterized by narrow conical (trees 41 to 60 years of age at breast height) to flattened (trees 101 to 120 years of age at breast height) tree-tops, well-proportioned or little deformed (loeses up to 20%) crowns, and a relative crown length amounting to at least 56%.
PL
Celem pracy jest wyróżnienie jednorodnych grup rozkładów żerowisk jodłowca kolcozębnego Pityokteines spinidens Reitt. oraz ocena przydatności pojedynczego rozkładu gamma i mieszanego modelu, złożonego z dwóch lub trzech rozkładów składowych gamma, do modelowania rzeczywistych rozkładów jodłowca kolcozębnego na wiatrowałach jodły Abies alba Mill. Badania przeprowadzono w zbliżonych do naturalnych lasach z udziałem jodły, rosnących w Świętokrzyskim Parku Narodowym, w centralnej Polsce. Łącznie wykorzystano 56 wiatrowałów jodłowych. Analiza skupień pozwoliła na identyfi kację sześciu jednorodnych grup rozkładów żerowisk jodłowca kolcozębnego. Badany gatunek zasiedlał różne części wiatrowałów; analizowane rozkłady różniły się znacznie pod względem symetryczności, spłaszczenia, liczby lokalnych maksimów i losowej, lokalnej regularności. Badania potwierdziły przydatność i wszechstronność modelu gamma, pojedynczego oraz mieszanego, złożonego z dwóch lub trzech komponentów; zastosowane modele gamma mogą być wykorzystane do modelowania rozkładów żerowisk jodłowca kolcozębnego na wiatrowałach jodły.
EN
Modelling of Pityokteines spinidens Reitt. egg galleries distributions on silver fi r Abies alba Mill. windfalls. The objectives of the study are to identify homogeneous groups of Pityokteines spinidens Reitt. egg galleries distributions as well as to assess the usefulness of the single gamma distribution and the mixtures consisting of two or three gamma distributions for modelling the empirical P. spinidens distributions on silver fi r Abies alba Mill. windfalls. The study was conducted in near-natural forests with A. alba growing in the Świętokrzyski National Park in central Poland. In total, 56 A. alba windfalls were analysed. The hierarchical cluster analysis identifi ed six P. spinidens egg galleries distributions clusters having similar structures. The examined species have infested various parts of the windfalls; the analysed distributions varied considerably in terms of symmetry, fl attening, numbers of the local maxima and random, local irregularity. The analysis revealed high suitability and versatility of gamma distribution both as single form as well as two− and three–component mixture; used gamma models can be employed for modelling P. spinidens egg galleries distributions on A. alba windfalls.
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