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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Influence of initial light intensity and deer browsing on Taxus baccata saplings: a six years field study

100%
Iszkulo G., Nowak-Dyjeta K., Sekiewicz M.
Dendrobiology
|
2014
|
tom 71
European yew (Taxus baccata L.) is a rare species, but is the focus of great interest because of the species recovery attempts and its use in medicine. The aim of this study was to determine the optimum conditions for the development of the young generation of this species. Four-year old yew seedlings were grown under artificial light reduction: 2, 8, and 30%, as well as in full light. The seedlings were then planted in natural conditions in fenced and unfenced areas. The results of six years field studies indicated that the greatest impact on survival was shown by the light conditions from the period before planting under the canopy of trees. Seedlings from the 2 and 8% of light showed the greatest mortality. The reason was the sudden change in light conditions, because at the time of planting (early spring), there was no reduction of light under deciduous trees. Almost all of the unfenced yew seedlings were grazed by deer, but yew survival in the unfenced group was surprisingly high despite the permanent grazing. This was explained by the high resistance of yew to cutting and the protection of seedlings by a dense layer of Rubus. The results indicated that yew trees require protection against animals for normal development, even if animals have not previously had contact with Taxus and that yew seedlings are very sensitive to sudden changes in light. Both conclusions can be applied in the development of natural and artificial regeneration of European yew and other endangered plants.
2
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Seed vigor, photosynthesis and early growth of saplings of different triploid Betula families

80%
Mu H., Jiang J., Li H., Liu G.
Dendrobiology
|
2012
|
tom 68
Breeding scientists have given extensive attention to triploids in trees because of their importance to forestry. Consequently, creating and breeding triploids of good quality has become one of purposes of tree breeding. We chose two autotetraploids (Betula platyphylla, named Q10 and Q65) as female parents and eight hybrid diploids (B. platyphylla × B. pendula, named F1 – F8) as male parents to obtain progenies through controllable pollination, resulting in triploid progenies. Germination rate and germination energy of triploid seeds of Q65 were significantly higher (P < 0.01) than in triploid seed s of Q10. Triploid families with Q65 as female parent had a large quantity of saplings, whereas triploid families with Q10 as female parent had a small quantity of saplings. Triploid families with Q65 as female parent were generally superior in base diameter and height to base diameter ratio when compared to a diploid family. Q65×F3 was preliminarily recognized as the superior family. These results demonstrate that the female parent has a major influence on triploid progenies, although the male parent also has a small influence. The results provided a reference to build seed orchards of triploid birch trees, choose tetraploids as female parents and forecast triploid families of good quality.
3

Wplyw czyszczen poznych na ksztaltowanie sie cech biomorfologicznych i budowy pietrowej podrostu jodly [na przykladzie powierzchni doswiadczalnej w Brzozowie-Jahonce]

80%
Jaworski A., Paluch J.
Acta Agraria et Silvestria. Series Silvestris
|
1998
|
tom 36
15-30
During 1983-1989 late cleanings were carried out in silver fir up-growth. Cuttings based on a positive selection had the most benefical effect on the biomorphological characteristics of silver fir up-growth. They were most intensive and led to increased increment in diamater of the stem and length of the crown, and also to storeyed structure of the up-growrh. Promotion of the most valuable individuals which in future should form the overstorey of the stand is also an important advantage of this treatment. In comparison with the control treatment the negative selection had a statistically significant effect on the height and diameter increment, change in absolute length of the crown and its height above the ground, as well as the number of its whorls. However, the negative selection led to disappearance of height differentiation in the silver fir biogroups.
4

Seasonal changes in foliage biomass and age composition of live and falling needles in Scots pine saplings treated with sulphuric acid, urea, or lime

80%
Tarabula T.
Polish Journal of Ecology
|
2002
|
tom 50
|
nr 3
5

Wplyw roznych metod selekcji stosowanych w pielegnacji podrostu jodly na ksztaltowanie sie jego cech biomorfologicznych [na przykladzie powierzchni w Brzozowie-Podlesiu]

71%
Jaworski A., Paluch J.
Acta Agraria et Silvestria. Series Silvestris
|
1999
|
tom 37
11-26
Tending operations were carried out in about 20 year old silver fir upgrowth in 1983 and 1989. They were evaluated in 1995 when different biomorphological characteristics of young firs were analysed. The operations based on the positive selection stopped the process of crown reduction and resulted in increased diameter increment. In case of firs in the lower tree layer they also resulted in increased height increment. Trees in the combined variant reacted with increased diameter increment and formed longer crowns. However, the combined treatment led to disappearance of natural height differentiation of the upgrowth and simplification of its structure which in conse­quence reduced its potentiality for practical utilisation. The negative selection in comparison with the control variant had no significant effect on the biomorphological characteristics of tree.
6

Rozmiar szkod powstalych w podrostach jodly i swierka w wyniku scinki i obalania drzew w przedplonowym drzewostanie sosnowym i drzewostanie swierkowym

61%
Sowa J. M., Szewczyk G.
Acta Agraria et Silvestria. Series Silvestris
|
2000
|
tom 38
75-90
The paper presents the dimension of damage in fir and spruce upgrowth during light felling, carried out in predominant stand of mountain forests. The work was limited to the analysis of damage in up growth. Weak relation between the quantity of obtained wood and the dimension of damage in renovations defined to what extent the morphological build of predominant forest and trees location in the area influence the dimension of damage during cutting. Total dimension of all types up growths damage ranged from 2.6 to 12.6 in pine stand and from 1.7 to 4.7 in spruce stand.
7

Poziom uszkodzen odnowienia w wyniku stosowania reczno-maszynowych technologii pozyskiwania drewna

61%
Stanczykiewicz A.
Acta Agraria et Silvestria. Series Silvestris
|
2006
|
tom 44
91-116
The level of damages in regeneration caused by manual and mechanical technologies under short wood (assortment) and long wood systems of timber harvesting is presented in this paper. Studies were carried out under different physiographic conditions of southern Poland, i.e. mountain regions (Jeleśnia Forest District, Forest Experimental Station in Krynica), submountain regions (Gromnik Forest District), and lowland regions (Krzeszowice Forest District), in coniferous as well as broadleaf stands where final cuttings and selection thinnings were conducted. The lowest damage level was found in mountain stands, and during early thinnings, while the highest level in lowland stands, and during final cuttings. In the case of technologies used under short wood system the level of damages was by 30% higher than in the case of long wood system.
8

Wpływ pozyskania drewna na stan odnowienia naturalnego kilkanaście lat po użytkowaniu na przykładzie lasów w Beskidzie Wyspowym

51%
Gaj-Gielarowiec D., Gielarowiec K.
Acta Agraria et Silvestria. Series Silvestris
|
2013
|
tom 51
The study concerns an assessment of the change dynamics in the lower floor of the forest and was perfomed in the mountain forests in Lubogoszcz forestry. It is a continuation of long-term follow-up of the Department of Forest and Wood Utilization. The aim of this study is to answer various questions relating to: changes in the amount of regeneration areas used and unused after several years of obtaining wood. A deep analysis shows increase in number of total regeneration. There is a similar increase in natural seeding and understorey on the surfaces used and unused. Analysis of the dynamics of species recomposition showed that the main species in the lower floor is beech. Based on statistical analysis no significant correlations between the damage from chopping and skidding and the size of the recovery after several years of using were found.
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