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1
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Ekologiczne konsekwencje hodowli drzew w roznym zageszczeniu. I. Wzrost i rozwoj drzewostanu

100%
Jagodzinski A. M., Oleksyn J.
Sylwan
|
2009
|
tom 153
|
nr 02
75-85
2

Cięcie letnie w świetle nauki i praktyki

84%
Mika A.
Owoce, Warzywa, Kwiaty
|
1991
|
nr 15
3
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Wpływ trzebieży na wzrost i produkcyjność drzewostanów sosnowych na przykładzie doświadczenia w Kazlu Ruda (Litwa)

84%
Linkevicius E., Bijak S., Godvod K., Petrauskas E., Tiskute-Memgaudiene D., Valiukaite R., Sapokas A., Satinskas R.
Sylwan
|
2019
|
tom 163
|
nr 09
One of the main tasks for the forest managers is to form the highly productive stands, and it is mainly performed by applying intermediate cuttings during the stand development. As the impact of thinning on the premature Scots pine, commercially most important species in Lithuania, has not been sufficiently investigated yet, our objective was to evaluate the impact of such treatments on the growth and yield of the pine stands by using data from the long term experimental plots. The described thinning experiment was established in 1983 in Kazlų Rūda (54.760395°N, 23.517736°E), in the 30−years−old Scots pine forest, growing in oligotrophic site conditions. Four square plots with the size of 0.25 ha each were set. The first one (5) was left as a control variant with no thinning, while the others were subjected to the treatments of different intensity. In variant 5A (slightly thinned) 15% of the basal area compared to the control plot was removed. Accordingly, in variant 5B (moderate thinning) 25% and in variant 5C (heavy thinning) 40% of basal area was subtracted. No additional thinning was implemented further during the experiment. Plots were re−measured at least 4 times with the last measurement in 2016, when the stand was 63 years old. The main result of this study was that after the 33 years no evident effect of various intensity of silvicultural treatments can be seen as the growth and yield of the un−thinned forest stand was the highest compared to the thinned ones. Growth and yield in the most intensely thinned stand reached 86 and 85% compared to the control variant, respectively. The best productive results were found for moderate thinning (92 and 89% of growth and yield of the un−thinned stand), while the worst – in the slightly thinned 5A variant (77 and 83% of values for the control stand). Further on, the number of trees and competition level in all plots were very different when the experiment was established. Yet after 33 years, these differences were remarkably reduced. Accordingly, the diameter distributions, being very different at the beginning of the experiment, eventually became very similar in all experimental plots. Finally, the results showed that in un−thinned forest stand, natural mortality (self−thinning) of trees adjusted its density just in time. Thus this stand managed to keep its growing energy in later periods, avoiding degradation or destruction predicted by some theories.
4
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Wzrost drzewostanu sosnowego do fazy tyczkowiny w zależności od sposobu założenia uprawy na gruncie zalesianym

84%
Barzdajn W., Kowalkowski W., Szygula J.
Sylwan
|
2017
|
tom 161
|
nr 09
The aim of the study was to compare the growth of plantations established with manual and mechanical methods using planting material of various age. The experiment was established in 2000, in the Góra Śląska Forest District (W Poland) on a former farmland. One− and two−years−old Scots pine seedlings were used. Applied planting methods included: conventional planting bar, German Huff's dibble, trowel, Junack spade and three types of planting machines. The complete random block design with five replications was adopted. For the requirements of machine operation, unit plots were elongated rectangles with the longer side of 100 m and the shorter side of 4.5 m. Each plot consisted of three trenches. Spacing between seedlings in the trench was selected to ensure 10,000 seedlings/ha density. Measurements were carried out in 2000, 2001, 2002, 2003, 2008 and 2015. In the first five dates all heights were measured and seedling survival rates were established based on the number of measurements. In 2008 and 2015 all diameters at breast height were measured. In 2015 height of sample trees was recorded, while the height of the other trees was calculated according to the Prodan model h=d²/(a+bd+cd²)+1.3. Based on the measured diameters at breast height and established heights, basal area at the breast height and total tree volume were calculated for each plot. Survival rate is the primary parameter in the evaluation of planting methods, as it most effectively differentiates treatments. Stand height showed no significant diversification with regard to the treatments. For mean diameters at breast height the only differences were found between two−year old and one−year old seedlings, irrespective of the planting method. Despite the lack of differences in growth, effects of various planting methods and different planting material remain and as a result of high class timber already found in the stand these effects have become economically important. The decision on the selection of a particular planting material type and planting method has extensive economic consequences, as it affects productivity of grown stands at least at the first thinning operations. Planting machines are good tools in the establishment of forest cultures and the quality of their work exceeds that of manual operations.
5

Korony wrzecionowe czy rozpinane

84%
Mika A.
Owoce, Warzywa, Kwiaty
|
1991
|
nr 21
6
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Przesłanki od analizy zmienności siedliska leśnego na podstawie estymacji wysokości drzewostanu

84%
Sypka P.
Infrastruktura i Ekologia Terenów Wiejskich
|
2012
|
nr 3/IV
Dynamika wzrostu drzewostanu bardzo silnie zależy od klasy bonitacyjnej siedliska leśnego. Dodatkowo w drzewostanach zagospodarowanych bezzrębowo (odnowienia naturalne) można zaobserwować bardzo duże zróżnicowanie wysokości drzew, zwłaszcza w pierwszych latach ich życia. Drzewa rosnące pod okapem wykazują dość długi okres powolnego wzrostu, co jest głównie spowodowane ocienianiem przez górne piętro drzewostanu. Zgromadzone empirycznie dane wskazują również, że nawet długi powolny wzrost w zagłuszeniu nie uniemożliwia takim drzewom szybkiego wzrostu w późniejszym okresie ich życia. W pracy opisano metodę, pozwalającą określić zarówno zmienność jakości siedliska w czasie, a także szacunkowy czas wzrost w zagłuszeniu. Opracowany algorytm wykorzystuje model wzrostu drzewostanu zaproponowany przez Sulińskiego [2007]. Występujące w tym modelu parametry mają jednoznaczną treść ekologiczną. Weryfikacja metody została przeprowadzona na podstawie danych wysokości drzewostanów świerkowych wzrastających na różnych siedliskach w Puszczy Białowieskiej i Witowie (Tatry Zachodnie).
7

Drzewo roku 2013 - oliwnik. Oliwnik wąskolistny

84%
Czekalski M.
Szkółkarstwo
|
2013
|
nr 2
8

Formowanie nie tylko wiosną

84%
Mika A.
Owoce, Warzywa, Kwiaty
|
2011
|
nr 09
9

Przemyślane inwestycje

67%
Ryl K.
Owoce, Warzywa, Kwiaty
|
2014
|
nr 06
10

Dynamika wzrostu drzewostanów sosnowych w regionie Tarnobrzeskiego Zagłębia Siarkowego na przykładzie nadleśnictwa Buda Stalowska

67%
Orzel S., Grabczynski S., Raimer J., Rieger R.
Acta Agraria et Silvestria. Series Silvestris
|
1988
|
tom 27
11

Metoda obliczania rocznej produkcji biomasy w zbiorowisku lesnym w zaleznosci od wysokosci i wieku drzewostanu

67%
Sulinski J.
Acta Agraria et Silvestria. Series Silvestris
|
2007
|
tom 45
89-119
Referring to the Czarnowskis formula describing tree-stand height growth rate, a definition of height growth benchmark of site quality and a formula for its calculation have been developed. Besides, a formula connecting the height growth benchmark of site quality and the annual tree-stand biomass production has been constructed. The above benchmark was developed on premises that in clear-cut managed stands: (1) product values for annual maximum height growth and the age at which it takes place as well as (2) tree-stand height at which the annual height growth rate reaches maximum values are specific for any tree species irrespectively of the site quality. A formula connecting annual biomass production and height growth benchmark of site quality has been developed on premises that the highest possible annual biomass production as calculated for given tree species in a forest community is no lower than the site productivity. The coefficients values applied in respective formulae were calculated basing on data taken from the growing stock tables for five tree species: Scots pine, Norway spruce, European fir, European beech, and English oak. In total, the data for 148 height curves were taken into consideration while the annual biomass production was analyzed for 23 tree-stands. The developed formulae are of use for practical purposes however their applicability is to be restricted in the same way as restricted is the applicability of the growing stock tables that have been used for these formulae identification.
12
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Zróżnicowanie bonitacji wzrostowej drzewostanów daglezjowych w Polsce

67%
Bijak S.
Sylwan
|
2017
|
tom 161
|
nr 03
The objective of the study was to analyse the site index (SI) of Douglas fir (Pseudotsuga menziesii) stands in relation to the forest habitat type, soil type and relief characteristics. We utilised information available in the Information System of the State Forests in Poland that included selected parameters describing habitat conditions and dendrometric characteristics of Douglas fir stands. In total, processed data referred to 863 stands with a total area of 1,644.45 ha. As the SI distribution was not consistent with the normal one (Shapiro−Wilk test, p <0.0001) we applied Kruskal−Wallis or Mann−Whitney tests to assess the significance of observed differences. Site index of surveyed stands ranged from 19.9 to 47.8 m, 32.6 m on average (standard deviation of 3.3 m). Douglas fir in northern and southern Poland characterized by higher SI than in western and south−western part of the country (HK−W=83.5; p<<0.001; fig. 2). Forest habitat type significantly distinguished analysed stands (HK−W=30.1; p<<0.001). The highest SI values were observed for mixed deciduous habitats (fig. 3). For more fertile fresh deciduous habitats Douglas fir achieved slightly lower site index, while the least fertile mixed coniferous habitats are characterized by significantly lower SI. Habitat moisture variant had no significant effect on the average SI values (HK−W=2.6; p=0.269). The highest values were found in strongly fresh habitats (32.8 ±4.1 m), while the lowest in the humid variant (31.7 ±3.4 m). We found significant influence of soil type (HK−W=23.2, p<0.001) even though the average SI values for each category were relatively similar (fig. 4). The highest values were observed for Cambisols (33.3 ±3.7 m), while the lowest for Arenosols (32.1 ±3.0 m). Particle size distribution is an important factor for Douglas fir site index (tab.). We found that the heavier material (the higher the content of silt and clay), the significantly higher SI values (HK−W =16.9; p=0.001). Mean SI for stands growing on former farmlands (32.0 ±3.3 m) and on forest areas (32.7 ±3.3 m) were not significantly different (ZM−W=1.73; p=0.084). There was no significant effect of the relief forms on site index surveyed Douglas fir stands apart from the fact that stands growing on slopes are characterized by significantly higher SI (ZM−W=1.99; p=0.047).
13
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Przestrzenne zróżnicowanie dynamiki wzrostu drzew ponad górną granicą lasu na Babiej Górze

67%
Michalowicz P., Czajka B., Kaczka R. J.
Studia i Materiały Centrum Edukacji Przyrodniczo-Leśnej
|
2014
|
tom 16
|
nr 3[40]
14

O wykorzystaniu etefonu w sadach

67%
Basak A.
Owoce, Warzywa, Kwiaty
|
2007
|
nr 11
15

Regulowanie wzrostu drzew

67%
Goscilo P.
Owoce, Warzywa, Kwiaty
|
2011
|
nr 02
16

Czytelnicy pytają

67%
Mika A.
Owoce, Warzywa, Kwiaty
|
2011
|
nr 21
17

Najważniejsze w marcu

59%
Goscilo P.
Owoce, Warzywa, Kwiaty
|
2013
|
nr 03
18

Jak chronić drzewa? (część VI)

59%
Wieteska K.
Pszczelarstwo
|
2012
|
tom 63
|
nr 03
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