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:
    Możliwość zastosowania rozkładów mieszanych do modelowania rozkładów pierśnic drzew w naturalnych klasach biosocjalnych
    Potential of mixture distributions application for modelling tree diameter distributions by natural social classes
    Autorzy:
    Zasada, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1026820.pdf
    Data publikacji:
    2003
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    drzewostany sosnowe
    rozklad piersnic
    klasy Krafta
    lesnictwo
    rozklad mieszany
    diameter distribution
    gamma distribution
    mixture distribution
    biosocial classes
    Opis:
    The aim of the presented study was to show an applicability of finite mixture distribution approach for estimating diameter distribution parameters of the dominant and suppressed stands on an example of one-layer, even−aged, pure Scots pine stands. This approach gave a good fit of compound distribution proportions, average d.b.h for the dominant and suppressed stands and standard deviations of d.b.h. for the analysed classes.
    Źródło:
    Sylwan; 2003, 147, 09; 27-37
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Wzorzec rozkładu pierśnic drzew wielowarstwowego drzewostanu jodłowego Gór Świętokrzyskich
    Pattern of breast height diameter distribution in a multilayer silver fir stand in the Swietokrzyskie Mountains
    Autorzy:
    Bruchwald, A.
    Dmyterko, E.
    Łukaszewicz, J.
    Niemczyk, M.
    Wrzesiński, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/989331.pdf
    Data publikacji:
    2016
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    Gory Swietokrzyskie
    drzewostany jodlowe
    jodla pospolita
    Abies alba
    rozklad piersnic
    metoda BDq
    diameter distribution
    abies alba
    bdq method
    Opis:
    In Poland, the majority of silver fir stands is characterised by a single−layer stand structure. The current silvicultural activities aim at obtaining multilayer stands, which requires a clearer definition of the structure, and more precisely, a better knowledge of the pattern of diameters at breast height (DBH) distribution. The aim of the research was to develop a pattern of DBH distribution of trees in a multilayer silver fir stand in the Świętokrzyskie Mountains (central Poland) using the BDq method, through the mathematical determination of function parameters, including the productive capacity of the habitat. The application of this pattern will allow the selection of the management methods aimed to obtain and then maintain model stands with a different layer structure. The research was based on the empirical material collected in 56 stands that were characterized by both a single− and a multi−layered structure. They grew in coniferous forest habitats, mostly in the upland mixed coniferous forest, upland mixed deciduous forest and upland deciduous forest or mountain forest. One big (up to 1 ha) or 3−5 smaller (0.04 ha) sample plots were established in each stand in which diameters at breast height of all trees and heights of usually 25 trees, selected from the entire range of diameters, were measured. These were used to determine the height growth curve equation coefficients and then the height of each tree. For each stand the basal area was calculated and a graph for DBH distribution was prepared. Site index was established using the original empirical equation. In order to develop a model for multilayer fir stands, individual parameters of the equation 5, such as the basal area (B), the target diameter at breast height (D) and the coefficient q were to be determined using the BDq method. Taking into consideration only stands with one−tailed DBH, individual parameters of the function were found to be associated with site index. Empirical equations were developed for the determination of B and D, and, based on the DBH distribution graphs, coefficient q associated with site index was also calculated (tab.). The developed DBH distribution pattern is a mathematical description of the target fir stand. When the value of stand parameters approaches those of the model stand, it should be managed using the shelterwood cutting system, which results from the spatial variation in the stand height structure, and consequently from the need for different silvicultural treatments in different stand fragments.
    Źródło:
    Sylwan; 2016, 160, 09; 741-750
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Uproszczony model rozkładu pierśnic jednowiekowych niepielęgnowanych drzewostanów sosnowych (Pinus sylvestris L.)
    Simplified model of diameter distribution for even-aged unthinned Scots pine (Pinus sylvestris L.) stands
    Autorzy:
    Jagiełło, R.
    Beker, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/986956.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    dendrometria
    sosna zwyczajna
    Pinus sylvestris
    drzewostany sosnowe
    drzewostany jednowiekowe
    drzewostany niepielegnowane
    rozklad piersnic
    rozklad uproszczony
    rozklad gamma
    diameter distribution
    gamma poisson
    scots pine
    unthinned stand
    Opis:
    Although modelling of the diameter at the breast height (DBH) distributions has long history, theoretical discrete distributions have not so far been used for this purpose. In this study we use measurements covering 25 years (six inventories) without silvicultural influence on 14 even−aged Scots pine (Pinus sylvestris L.) stands to develop the DBH distribution models. Analysed stands are located in Murowana Goślina Forest Experimental Station (W Poland). The objective of the study was to elaborate the most simplified model that applies stand variables easy to assess and uncomplicated theoretical distribution. We employed two−parameter Gamma Poisson (GP) distribution and compared it to Weibull (W) and Sb Johnson (SbJ) ones. When maximum likelihood estimation (MLE) was used, GP gave similar results to W and both were slightly worse than SbJ. We found that both DBH standard deviation and stand density have substantial impact for model bias when above distributions used. Stepwise regression analysis was used for obtaining linear equations for parameter prediction of GP distribution. Then, GP model was simplified by removing standard deviation of DBH (SDD) from equation for overdispersion parameter. Results showed slight increase in mean of error values (i.e. modified Reynolds e index and root mean square error) for simplified model (SGP) compared with those for model including SDD, but differences in means were insignificant. Minimal and mean DBH represent enough variability of diameter distribution to obtain appropriate model based on Gamma Poisson distribution. Error was only 5% greater from four−parameter SbJ (MLE) distribution with similar range: 8.2−28.8% against 5.1−25.5% for SGP and SbJ respectively. The presented model can be used in many branches of forestry for more accurate calculation of stand level variables, when additional allometric equations employed, for instance assimilation apparatus volume or below− and aboveground biomass.
    Źródło:
    Sylwan; 2017, 161, 10; 822-830
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Kształtowanie zróżnicowanej struktury drzewostanów z wykorzystaniem metody BDq
    Application of the BDq method in uneven-aged stands silviculture
    Autorzy:
    Brzeziecki, B.
    Kornat, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/973764.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    struktura drzewostanu
    ksztaltowanie struktury
    rozklad piersnic
    metoda BDq
    diameter distribution
    stand conversion
    stocking control
    sustainable yield
    uneven−aged
    silviculture
    BDQ method
    Opis:
    The BDq method, a tool of stocking control in uneven−aged stands, with a special reference to the problem of determining diameter structure of cuttings, is introduced. Both theoretical foundations, as well as a practical application of the BDq method are presented on the example of conversion of two−storied stands, consisting of silver fir and Scots pine, to stands characterized by a plenter−like structure.
    Źródło:
    Sylwan; 2011, 155, 09; 589-598
    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:
    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:
    Wpływ trzebieży przerębowej na zróżnicowanie strukturalne drzewostanu
    Autorzy:
    Bilski, M.
    Brzeziecki, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/1022233.pdf
    Data publikacji:
    2005
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    dominacja wymiarowa
    rozklad piersnic
    trzebiez przerebowa
    lesnictwo
    struktura drzewostanu
    rozmieszczenie przestrzenne
    drzewa lesne
    drzewostany jodlowe
    abies alba mill.
    angle measure index
    bwinpro model
    differentiation thinning
    diameter distribution
    diameter spatial diversity
    liocourt−meyer curve
    spatial pattern
    stand structure
    Opis:
    The impact of differentiation thinning on various aspects of structure of exemplary Silver fir stand, including overall diameter distribution, diameter spatial diversity, dimension dominance and spatial distribution pattern, is analysed. Comparison of empirical diameter distribution (before and after thinning) with a the−oretical Liocourt−Meyer curve and the results of structural analysis, lead to the general conclusion that in case of relatively simple−structured Silver fir stands, achieving a desired, plenter−like structure is a longterm process, requiring a lot of consistency and patience.
    Źródło:
    Sylwan; 2005, 149, 04; 21-33
    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