Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "rozklad piersnic" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-7 z 7
    Tytuł:
    Struktura grubosci drzewostanow sosnowych wzrastajacych w roznych strefach przemyslowego uszkodzenia
    Autorzy:
    Orzel, S.
    Rutkowska, L.
    Powiązania:
    https://bibliotekanauki.pl/articles/822222.pdf
    Data publikacji:
    2000
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    drzewostany sosnowe
    tereny przemyslowe
    rozklad piersnic
    lesnictwo
    piersnice drzew
    Źródło:
    Sylwan; 2000, 144, 07; 55-63
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Modelowanie rozkładów pierśnic młodocianych drzewostanów brzozy brodawkowatej na gruntach porolnych za pomocą dwuparametrowego rozkładu Weibulla
    Modeling dbh distribution of young silver birch stands on former agricultural lands with the 2-parameter Weibull distribution
    Autorzy:
    Zasada, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/991512.pdf
    Data publikacji:
    2013
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    dendrometria
    drzewostany mlode
    grunty porolne
    drzewostany brzozowe
    brzoza brodawkowata
    Betula pendula
    piersnice drzew
    rozklad piersnic
    modelowanie
    rozklad Weibulla
    betula pendula
    secondary succession
    diameter distribution
    weibull
    Opis:
    The paper presents the diameter distributions of young silver fir stands (Betula pendula Roth.) growing on former agricultural lands described using the 2−parameter Weibull distribution. Various methods of parameters' estimation were tested: maximum likelihood method, method of moments and percentile approach. It was found, that the diameter distributions in such birch stands can have various shapes and forms – from close to the exponential to almost normal. The shape parameter were not affected by the age of the stand, but the scale parameter was strongly correlated with age. The most efficient methods for the tree diameter distribution modeling using the 2−parameter Weibull distribution are the method of moments and the maximum likelihood method. However, the obtained results does not exclude the percentile method, which is relatively simple and can be further modified for obtaining better results.
    Źródło:
    Sylwan; 2013, 157, 04; 268-277
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Szerokość pasma jądrowego estymatora rozkładu pierśnic w drzewostanach olszy czarnej (Alnus glutinosa (L.) Gaertn.) z zachodniej części Kotliny Sandomierskiej
    Bandwidth of kernel estimator of DBH distribution in black alder (Alnus glutinosa (L.) Gaertn.) stands from west part of the Sandomierz Basin
    Autorzy:
    Pogoda, P.
    Ochał, W.
    Orzeł, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/985919.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    dendrometria
    drzewa lesne
    olsza czarna
    Alnus glutinosa
    piersnice drzew
    rozklad piersnic
    estymacja
    estymatory jadrowe nieparametryczne
    kernel estimator
    bandwidth
    dbh structure
    black alder
    Opis:
    Set of ‘nonparametric’ methods, that don’t make a priori assumption about functional form of empirical distribution was developed as an alternative to the parametric distribution modeling. The kernel estimators are one of such methods, that can be used to describe the frequency of data representing for example DBH records. Kernel smoothing requires the choice of weighting function and bandwidth also called as smoothing parameter or window. The lack of comprehensive analysis on the applicability of particular bandwidth selection methods to model DBH structure gave an impulse to present investigation aimed at determining value and variability of smoothing parameter in black alder stands. The optimal bandwidth was obtained according to six different variants of plug−in method proposed by Altman and Léger. Presented investigations were based on DBH measurements collected in 163 managed black alder stands aged from 6 to 89 years, growing in the west part of the Sandomierz Basin (S Poland). We measured in total 22,530 black alders, from 48 to 359 in individual stand. Stands were characterized by: age, quadratic mean diameter, basal area, mean height, Reineke’s stand density index and standard deviation of DBH. Smoothing parameter was obtained by means of plug−in method with the pilot bandwidth selected by: Silverman’s rule of thumb (nrd0), Scott’s method (nrd), unbiased cross−validation (ucv), biased cross−validation (bcv), method of Sheather and Jones (sj) and one−stage method of Wand and Jones (onestage). The bandwidth was first obtained to real data, then to 100 bootstrap samples of 5, 10, 15 ... and 100 trees from each stand. Smoothing parameters were characterized by mean and variance. Relationship between values of smoothing parameter and stand characteristics was determined. Finally the influence of sample size on value and variability of bandwidth was assessed. Value and variability of smoothing parameter in black alder stands are determined by stand age, sample size and method of bandwidth choice. There is a close relationship between bandwidth and the mean height (r from 0.75 to 0.83), quadratic mean diameter (r from 0.79 to 0.88) and standard deviation of DBH (r from 0.84 to 0.93). Potentially these stand features can be used to predict smoothing parameter values. Minor changes of bandwidth for samples containing above 50 trees together with persistence of standard error give an objective grounds for defining optimal number of diameters, that are necessary to kernel estimation of DBH distribution.
    Źródło:
    Sylwan; 2018, 162, 05; 411-421
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Rozkłady teoretyczne najlepiej aproksymujące strukturę pierśnic w drzewostanach świerkowych regla górnego w rezerwacie przyrody "Śnieżnik Kłodzki"
    Theoretical distributions in approximation of breast height diameter structure in upper mountain zone Norway spruce stands in 'Snieżnik Klodzki' nature reserve
    Autorzy:
    Sinica, P.
    Tomusiak, R.
    Tkaczyk, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/989425.pdf
    Data publikacji:
    2016
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    regiel gorny
    rezerwat Snieznik Klodzki
    drzewostany swierkowe
    swierk pospolity
    Picea abies
    piersnice drzew
    rozklad piersnic
    aproksymacja
    rozklad teoretyczny
    dbh distribution
    stand structure
    native type forests
    picea abies
    Opis:
    The study on the structure of Norway spruce old−growth stands of original provenience in upper mountain zone was carried out in a nature reserve ‘Śnieżnik Kłodzki', located in the Lądek Zdrój Forest District (SW Poland). The fieldwork was conducted in three spruce stands located at the altitude of 1,215 and 1,235 m a.s.l. The breast height diameters (dbh) of living trees were characterized. The aim of this study is to characterize the structure of dbh of trees in spruce stands of subalpine forest. Implementation of the objective will be associated with the characteristics of empirical distributions dbh and an indication of theoretical distributions of continuous random variable best approximating the structure of dbh. The comparison of empirical dbh distributions with 36 theoretical distributions were carried out, but goodness−of−fit tests proven statistically significant compatibility with seventeen of them: beta (4−parameter), Cauchy, exponential power, folded normal, gamma (3−parameter), generalized logistic, Laplace, logistic, loglogistic, loglogistic (3−parameter), lognormal (3−parameter), noncentral chi−square, normal, smallest extreme value, triangular, Weibull and Weibull (3−parameter). The dbh distributions in upper mountain spruce stands are the best fitted with logistic distribution, and subsequently loglogistic (3−parameter), generalized logistic and Weibull (3−parameter) distributions. That four distributions can be used in individual tree growth models while generating structure dbh of trees in the stand. The knowledge of dbh structure in protected stands could be helpful in shaping spruce stand structure in planned silvicultural treatments, and shows the need for silvicultural treatments in upper mountain spruce stands.
    Źródło:
    Sylwan; 2016, 160, 11; 905-914
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Modele struktury grubości w jednopiętrowych drzewostanach z udziałem jodły Abies alba Mill. i buka Fagus sylvatica L.
    Models of diameter structure in single-storied stands with fir Abies alba Mill.and beech Fagus sylvatica L.
    Autorzy:
    Podlaski, R.
    Pach, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/989766.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    drzewostany mieszane
    drzewostany jednopietrowe
    struktura grubosci
    jodla pospolita
    Abies alba
    buk zwyczajny
    Fagus sylvatica
    piersnice drzew
    rozklad piersnic
    rozklad Weibulla
    forest patches
    structural heterogeneity
    tree diameter distribution
    weibull distribution
    Opis:
    The objectives of the study were (1) to determine the models of diameter at breast height (dbh) distributions in single−storied mixed stands with fir Abies alba Mill. and beech Fagus sylvatica L. as well as (2) to assess the usefulness of Weibull distribution to approximation of empirical dbh distributions for distinguished models. In the Carpathians (southern Poland) and in the Świętokrzyskie Mountains (central Poland) 36 sample plots ranging in size from 0.1 to 0.4 ha were established. To identify the dbh distribution models in single−storied stands with similar empirical dbh distributions, the hierarchical cluster analysis (HCA) with the Jaccard's measure and the Ward's minimum variance agglomeration method was used. To approximate dbh distributions, the Weibull distribution was employed. Single−storied mixed stands with fir and beech, with the mean age between 50 and 70 years at the dbh, were characterised by a large diversity of dbh distributions. Three groups of stands (I, II, III) differing, among others, in average dbh were determined (fig. 1). In these groups the average dbh ranged from 23.5 to 32.6 cm, from 18.9 to 25.1 cm, and from 13.7 cm to 19.6 cm, respectively. Within these groups, seven models of unimodal distributions were selected (figs. 2−4; tab.). The models are characterised by varying degrees of asymmetry with the highest number of trees from less than 30/ha to more than 300/ha which occurred mainly in the dbh classes between 9 and 33 cm (models AS1, SM1, AS2, AS3, AS4, AS5, SM2). The results of χ² test indicate the high flexibility and suitability of Weibull distribution for modelling of such types of dbh structures.
    Źródło:
    Sylwan; 2015, 159, 07; 586-592
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Ocena przydatności wybranych funkcji do modelowania rozkładu pierśnic w drzewostanach olszy czarnej (Alnus glutinosa (L.) Gaertn.)
    Evaluation of usefulness of selected functions for modeling distribution of breast height diameter in black alder stands (Alnus glutinosa (L.) Gaertn.)
    Autorzy:
    Orzeł, S.
    Pogoda, P.
    Ochał, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/988989.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    drzewostany olszowe
    struktura grubosci
    olsza czarna
    Alnus glutinosa
    piersnice drzew
    rozklad piersnic
    rozklad teoretyczny
    aproksymacja
    modelowanie
    funkcja gestosci prawdopodobienstwa
    test Kolmogorowa-Smirnowa
    diameter at breast height
    diameter distribution
    probability density function
    kolmogorov−smirnov test
    Opis:
    We evaluated the usefulness of ten theoretical probability density functions for the approximation of the breast height diameter distributions in managed alder stands growing in the western part of the Sandomierz Basin (southern Poland). The study material consisted of measurement results for 22,530 alders obtained for 844 circular sample plots, established in 163 stands aged 6−89. In the area of particular stands, from 2 to 10 age−dependent circular sample plots sized 0.01−0.10 ha were systematically arranged. We evaluated the following theoretical probability distributions: normal (N), double normal (P−N), Johnson SB (J), Weibull (W), beta (B), Burr (Bu), gamma (G), log−normal (L−N), log−logistic (L−L) and Birnbaum−Saunders (B−S). Additionally the usefulness of the W, B, Bu, G, L−N, L−L and B−S distributions with omitted location parameter was tested. The goodness−of−fit of each probability density function was assessed based on the Kolmogorov−Smirnov statistic, the root mean square error and ranks established on their basis. It was found that DBH distribution of majority stands is characterized by right−sided asymmetry and negative kurtosis. It was showed that the best distribution for the breast height diameter structure approximation of alder stands is the Johnson SB (J) distribution. To describe the frequency of thickness, normal (N) and log−logistic (L−L) distribution should not be used. Elimination of location parameter significantly affects usefulness of probability density functions to modeling empirical distributions of breast height diameter. Gamma and Burr distributions with omitted location parameter gave the best results in description the frequency of breast height diameter. In certain situations, these distributions can also be used to describe the structure of breast height diameter of alder stands.
    Źródło:
    Sylwan; 2017, 161, 02; 101-113
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Charakterystyka wybranych drzewostanów jodłowych o złożonej strukturze na obszarze rdLP Katowice i Krosno
    Characteristics of silver fir stands [Abies alba Mill.] with composite structure on the area of Krosno and Katowice Directorate of Sate Forests
    Autorzy:
    Niemtur, S.
    Zawada, J.
    Ambroży, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1015928.pdf
    Data publikacji:
    2007
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    RDLP Krosno
    wysokosc
    rozklad piersnic
    Abies alba
    przyrost grubosci
    lesnictwo
    piersnice drzew
    RDLP Katowice
    jodla
    liczebnosc drzew w klasach wieku
    drzewa lesne
    drzewostany jodlowe
    silver fir stands
    selection cutting
    continuous cover forestry
    stand structure
    regenerations
    Opis:
    The clear improvement in vitality of silver fir stands is being observed in recent years, they are also intensifying of aiming at increasing participation of the fir in Carpathians forests with simultaneous form of the selecting structure of stands. However suitable silviculture methods depend first of all on the current state of stands. Our results showed that all investigated fir stands need shorter or longer period of transformation for applying of selection cutting methods.
    Źródło:
    Sylwan; 2007, 151, 02; 7-18
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-7 z 7

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies