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Wyświetlanie 1-3 z 3
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:
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:
Charakterystyka wybranych drzewostanów jodłowych Beskidu Niskiego i sposoby ich zagospodarowania
The characteristics of selected fir stands in Beskid Niski and the method of their management
Autorzy:
Bruchwald, A.
Dmyterko, E.
Niemczyk, M.
Łukaszewicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/989908.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
gory
Beskid Niski
drzewostany jodlowe
struktura drzewostanu
liczba drzew
piersnicowe pole przekroju
miazszosc drzew
zagospodarowanie lasu
stand layer
multi−layer structure
bdq method
abies alba
Opis:
Assuming multilayer structure as optimal for silver fir stands, we attempted to answer the following questions: 1) how to describe such structure, 2) to what extent does the structure of a particular stand differ from the optimal one, and 3) how to obtain the optimal structure. The study was based on the material collected in 12 stands in the Nawojowa Forest District (S Poland). Three to five 0.04 hectare circular plots were established in each stand, and diameters at breast height (d) of all trees with d > 7 cm were measured. Height (h) was measured for 25 trees selected within the stand. The top height determined for each stand enabled to classify trees into two layers: higher (group I) or lower (group II) than ⅔ of top height. Trees with d<7 cm were divided into 3 layers according to the height: III – h>2 m (higher upgrowth), IV – h between 0.5 and 2 m (lower upgrowth), and V – h<0.5 m (seedlings). Trees in layer V were counted on a 0.005 ha plot, while trees in layers IV and III on a 0.04 ha plot. The selected fir stands revealed high diversity in basic characteristics (tab. 1 and 2). The number of trees in layer III was higher than in layer II only in one stand, and was larger than the number of trees in layer I. Moreover, the variation in tree height formed a vertical canopy closure. The stand was considered to be a model one, and used to develop diameter distribution according to the BDq method. Most stands characterized a smaller number of trees in lower and larger in higher diameter classes compared to the model distribution. It seems that large number of thick trees prevent satisfactory growth of thinner trees. Fir stands proved to have a mosaic vertical structure. In some fragments, eight classes can be distinguished including one layer only: 1) upper (I), 2) middle (II), 3) upgrowth (III), combination of layers: 4) I and II, 5) I and III, 6) II and III, 7) I, II and III, and 8) gaps. The multi−layer structure of fir stands can be maintained only in the form of such a mosaic, but single−layer fragments are also needed to enhance the natural regeneration. We could select a stand with a close−to−optimal multilayer structure, which was considered as a model one and its diameter distribution was used in the BDq method. A comparison of the model curve with the empirical distribution of diameters at breast height for the stand under consideration allows determining diameter classes with an excess of trees that can be harvested without the fear of losing the multilayer structure of the stand. Whether a given tree has to be cut should depend on the vertical differentiation of trees in a particular fragment of the stand. In further studies, measurements in multilayer fir stands should be conducted to verify the model distribution.
Źródło:
Sylwan; 2015, 159, 09; 722-731
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

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