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Wyświetlanie 1-2 z 2
Tytuł:
Wydajność aparatu asymilacyjnego sosny zwyczajnej (Pinus sylvestris L.) różnych klas wieku
Productivity of the assimilation apparatus of Scots pine (Pinus sylvestris L.) in various age classes
Autorzy:
Turski, M.
Beker, C.
Jaszczak, R.
Powiązania:
https://bibliotekanauki.pl/articles/989700.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
drzewostany sosnowe
klasy wieku
klasy Krafta
drzewa lesne
sosna zwyczajna
Pinus sylvestris
aparat asymilacyjny
wydajnosc aparatu asymilacyjnego
volume of leaved twigs
productivity of assimilating apparatus
age classes
kraft's classes
Opis:
Productivity of the assimilating apparatus is commonly defined as an increment in volume, most typically of the stem or trunk, per unit of crown size. In this paper the productivity of the assimilating organ (CPtwn1) is calculated as a quotient of the average annual increment in stem volume from a 5−year period (iv1) and the volume of twigs with needles (twnv), determined by xylometry methods (fluid displacement method). The experimental material comprised measurements taken on 200 Scots pines (Pinus sylvestris L.) in 8 pure pine stands growing in western Poland (tab. 1). Using the calculated sizes of assimilating apparatus, their arithmetic means and coefficients of variation were calculated for each stand (tab. 2, 3). Additionally, mean crown productivity within each Kraft's class comprising the dominant trees (classes 1, 2 and 3) as well as in the dominated trees (classes 4 and 5) were determined. The strength of the relationship between CPtwn1 and diameter at breast height (d1.3), height (h) and volume of leaved twigs (twnv) was calculated (tab. 4). Moreover, a two−way analysis of variance was conducted to assess the statistical significance of the effect of age of the stand and biosocial class of tree position in the stand (within the dominant trees and the dominated trees) on productivity of the assimilating apparatus. Mean productivity of analysed Scots pine crowns takes the highest values in the youngest stand (0.60 m³), while the lowest – in the oldest stand (0.34 m³). In the youngest, 25−year old pine stand, mean productivity of the assimilating apparatus in trees forming the dominated trees is by 124% greater than that of trees forming the dominant trees. An opposite situation is found in the oldest, 93−year−old stand, where mean productivity of the dominant trees is over 1.5 greater than that recorded in the dominated trees. Statistically significant effect of the stand age on productivity of the assimilating apparatus was observed (tab. 5). However, affiliation of a tree to the dominant or dominated trees does not result in such an effect. On the other hand, there is an interaction between age of the stand and its affiliation to the Kraft's classes. This means that the affiliation of trees to the dominant trees or the dominated trees and its effect on mean productivity of the assimilating apparatus depend on the age of stand.
Źródło:
Sylwan; 2015, 159, 01; 36-44
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wielkość i wydajność aparatu asymilacyjnego sosny zwyczajnej (Pinus sylvestris L.)
Size and efficiency of Scots pine (Pinus sylvestris L.) assimilation apparatus
Autorzy:
Beker, C.
Turski, M.
Kaźmierczak, K.
Najgrakowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/979342.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
drzewostany sosnowe
sosna zwyczajna
Pinus sylvestris
aparat asymilacyjny
masa igliwia
wydajnosc aparatu asymilacyjnego
leśnictwo
drzewa leśne
masa ulistnionych gałązek
mass of twigs covered with needles
mass of needles
efficiency of assimilation apparatus
Opis:
The aim of the study is to analyse the size and efficiency of assimilation apparatus of Scots pine (Pinus sylvestis L.) using the site index model for unthinned pine stands (Model Pinus). The size of the assimilation apparatus was regarded in terms of mass of the twigs covered with needles (Ugc) and mass of needles (Ic). It reaches maximum values at the age of 20−25 years, then dynamically decreases to the age of 50 years, stabilizes between 50 and 80 years and from the age of 85 to 120 years again shows a mild increasing trend. The maximum mass of twigs covered with needles is from 40 (BON34) to 20 (BON26) t/ha, while mass of needles – from 25 (BON34) to 13 (BON26) t/ha. The minimum weight is from 18 (BON34) to 16 (BON26) t/ha and from 13 (BON34) to 11 (BON26) t/ha, respectively. The efficiency of the assimilation apparatus determined as the dependence of the current volume increment on in the dependence on mass of twigs covered with needles (WUgc) or mass of needles (WIc) is dynamically increasing and at the age of 45 years it reaches the maximum and then shows a downward trend to the age of 120 years. At the culminating point of these features, they are similar for all site indices and range from 0.83 to 0.88 m3/t (WUgc) and from 1.23 to 1.31 m3/t (WIc).
Źródło:
Sylwan; 2020, 164, 01; 3-9
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-2 z 2

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