Informacja

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

Wyszukujesz frazę "diameter spatial diversity" wg kryterium: Temat


Wyświetlanie 1-2 z 2
Tytuł:
Tempo wzrostu wysokości i pierśnicy jodły pospolitej (Abies alba Mill.) w Beskidzie Niskim
Height and diameter growth rates of silver fir (Abies alba Mill.) growing in Beskid Niski mountains
Autorzy:
Bruchwald, A.
Dmyterko, E.
Niemczyk, M.
Łukaszewicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/989756.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
drzewa lesne
jodla pospolita
Abies alba
wzrost roslin
wysokosc drzew
piersnice drzew
przyrost piersnicy
przyrost wysokosci
tempo wzrostu
Beskid Niski
height growth rate
diameter growth rate
spatial diversity of canopy layers
physical age
abies alba
Opis:
Silver fir is one of the main tree species of mountain and foothill forests in Poland that in optimal conditions forms pure stands with multi−layer structure. The study objective is to present differences in height and diameter growth rates of firs growing in upper stand layers and in the undergrowth. The research was conducted in 12 fir stands located in the Beskid Niski Mts. (southern Poland). In each stand height and diameter at breast height (dbh) were measured for 25 fir trees in order to develop a height curve. The first canopy layer included trees that were higher than ⅔ Hmax established from the height curve of the tree with the largest dbh. Height and diameter were measured on eight trees selected from the first canopy layer. An increment core was extracted at breast height in order to estimate the tree age. From the third canopy layer, which included trees higher than 2 m with dbh below 7 cm, five trees were selected. After cutting those trees, the length of the last ten branch whorls was measured. Five−year ring width measurements starting from the bark towards the pith were done at the stem cross−sections obtained at breast height. The number of rings was counted on remaining stumps. Height growth rate was defined as the height at the base age of 100 years (eq. 1). For the first canopy layer, the height growth rate was on average 31.8 m, while for the undergrowth it was 12.1 m. There was also large difference between diameter growth rate of the first stand canopy layer (55.7 cm) and undergrowth (18.3 cm). Both differences were significant at p=0.05. These discrepancies could result from low amount of light reaching the forest floor. The correlation between height and diameter growth rates and undergrowth tree age was negative in both cases. Long periods of shading result in smaller number of firs reaching the first canopy layer. Assuming that uneven−aged stand structure is optimal for that species, it should be characterized by a spatial variability (mosaic) of various canopy layers including even−aged patches with sparse canopy closure as well as gaps where fir regeneration will be initiated having favorable growth conditions.
Źródło:
Sylwan; 2015, 159, 10; 804-812
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 1-2 z 2

    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