Wyniki wyszukiwania - Biblioteka Nauki

1

Modernizacja maszyny wyciągowej

100%

Herbut A. , Gawron L. , Maciejczyk M.

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tom R. 49, nr 7

51-56

PL

W artykule przedstawiono metodykę modernizacji maszyny wyciągowej polegającą na zastosowaniu bezpośredniego regeneratywnego przemiennika częstotliwości średniego napięcia, wymianie układu zasilania I sterowania maszyny oraz układu hamulca pneumatycznego. Omówiono również komputerowy system wizualizacji i rejestracji pracy maszyny wyciągowej.

EN

The article presents a methodology of a winding machine modernization. The methodology is based on the use of a medium-voltage regenerative converter, the replacement of the machine supply and control system along with the air- brake system. Additionally, a computer-based system for visualization and registration of the winding machine operations was described.

2

Wartość hodowlana polskich populacji sosny zwyczajnej na powierzchni doświadczalnej w Rogowie

100%

Szeligowski H. , Buraczyk W. , Drozdowski S. , Gawron L.

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nr 12

EN

The paper analyses the variability of selected adaptive, growth and morphological parameters of 16 Scots pine provenances from Poland. Their silvicultural value and usefulness under the growth conditions in Central Poland were assessed. The empirical part was carried out on the experimental plot established in spring 1966 in Lipce Reymontowskie Forest Range, Rogów Forest Experimental Station. In subsequent surveys, the following characteristics were determined for each tree: diameter at the breast height, height, height of crown base and diameter of branches. All trees were also classified into 4 quality classes related to the stem straightness. The following analyses were performed: survival rate, course of height growth and diameter increment over age, variation of volume at single trees and whole stands level, diameter of branches, stem straightness, selected genetics and silvicultural properties. The assessment of silvicultural values pointed out that the best provenances include Dłużek, Karsko, Bolewice and Rychtal. Local provenances from Rogów and Spała are classified as the weak ones. Therefore in local Scots pine stands there is a need to improve quality, stability and yield. Obtained results deepen an existing knowledge on variability of Scots pine stands and demonstrate possibilities for verification of seed regionalization principles in Poland.

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Wpływ skracania systemów korzeniowych dwuletnich sadzonek świerka pospolitego (Picea abies L. Karst.) na ich wzrost po posadzeniu

88%

Buraczyk W. , Drozdowski S. , Szeligowski H. , Gawron L. , Karpiuk M.

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nr 07

4

Pomnikowe drzewa w Rezerwacie Ścisłym Białowieskiego Parku Narodowego

51%

Grzywacz A. , Keczynski A. , Szczepkowski A. , Bielak K. , Bolibok L. , Buraczyk W. , Drozdowski S. , Gawron L. , Szeligowski H. , Zajaczkowski J. , Brzeziecki B.

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nr 11

EN

The paper presents the main results of the comprehensive inventory of monumental trees in the Strict Reserve of the Białowieża National Park, which was conducted in years 2002−2017 on an area of ca. 4700 ha and included all live trees with diameter at breast height (dbh) exceeding a minimum threshold value ranging from 60 cm for hornbeam to 120 cm for oak. For every tree fulfilling this condition, species identity, circumference at 1.3 m (measured with tape), geo− graphical coordinates (GPS record) and health status (five classes) were determined. In total, 9190 trees from eleven different species were inventoried. Hornbeam, oak, maple, lime, ash and aspen were the most abundant with their total share in the amount of monumental trees equal to ca. 96%. The average density of monumental trees in the Strict Reserve was approximately 2 ind./ha. The majority (88%) of monumental trees were found in different subassociations of Tilio−Carpinetum community: T−C. calamagrostietosum, T.−C. typicum, T.−C. circaeaetosum alpine, T.−C. caricetosum remotae and T.−C. stachyetosum. As a rule, the fraction of particular species in the amount of monumental trees did not correspond to their fraction in the total pool of trees with dbh5 cm. Particularly high over−representation characterized oak, maple, ash and aspen. On the other hand, such species like spruce and, to a lesser degree, hornbeam, lime, alder and birch played much smaller role in the group of monumental trees than among all trees with dbh 5 cm. The monumental trees of particular species were distinguished by a high diameter differentiation. In this respect, oak clearly prevailed over the other ones. In contrast, the smallest dimensions were typical for hornbeam. The results obtained suggested the need of revision of minimum threshold values of circumference (and of corresponding dbh), used to classify a given individual as a monumental tree. This problem was particularly acute in case of pine, spruce, alder and birch. We suggest that the current minimum values of dbh for these species should be reduced by 10− −20 cm. Further, the comparison of the recorded values of dbh for some species with maximum values of dbh provided in the literature indicated the necessity of correction of the last values, both ‘in plus’ as well as ‘in minus’. For alder, aspen and maple, the current values should be increased by ca. 20−30 cm. On the other hand, for pine, the recent value should be reduced by at least 30 cm. We point out that the definition of large (monumental) tree is, to a large extent, an arbitrary issue. The various growth potential of particular tree species, occurring within a given area, implies that this definition should be used flexibly. It means a necessity of using different thresholds for different species and varied environmental conditions. Also, because of the relative rarity of large trees, the reliable estimation of their density can only be obtained on the basis of sufficiently large sample size. Some high values of density of large trees, which can be found in the existing literature (10−20 trees per hectare and more), may be the result of too small sample sizes.

5

Struktura i dynamika wielogeneracyjnych starodrzewów sosnowych występujących w obszarach ochrony ścisłej Kaliszki i Sieraków w Kampinoskim Parku Narodowym. Część 2. Procesy zamierania i dorastania oraz ich wpływ na rozkład grubości drzew

51%

Brzeziecki B. , Zajaczkowski J. , Olszewski A. , Bolibok L. , Andrzejczyk T. , Bielak K. , Buraczyk W. , Drozdowski S. , Gawron L. , Jastrzebowski S. , Szeligowski H. , Zybura H.

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nr 06

EN

Two fundamental demographic processes (tree recruitment and mortality) are analyzed for forest stands growing on permanent study plots located in strictly protected Scots pine−dominated, old−growth stands of Kampinos National Park (central Poland). The major implications of the observed demographic trends for the general shape of tree size distributions are determined, as well. During the past ca 30 years, in the stands sampled, there was a pronounced lack of balance between mortality and recruitment processes. Mortality rate was eight times higher than recruitment rate. Eventually, there was a net significant decline in population density, observed for all major tree species, including Scots pine, pedunculate oak, silver and downy birch, and black alder. As mortality processes affected mainly smaller trees, there was also a significant deterioration of the general demographic status of most important tree species. This effect was shown by the change of the overall shape of diameter distributions over the study period: from reverse J−shaped to flat curves running nearly parallel to X−axis. The values of recruitment rates were markedly lower, and the values of mortality rates – significantly higher, than analogous values characterizing comparable forests (e.g., those obtained for the natural stands of Białowieża National Park). Low recruitment rates, as obtained for Kampinos stands, suggest that presently, in the local, Scots pine−dominated, old−growth stands, the general conditions for forest regeneration and for maintaining a long−term demographic stability are unfavorable. Most probably, the regeneration of this type of forest has an episodic, ‘wave−like’ character and corresponds to the ‘catastrophic’ model, according to which the successful regeneration of current dominants (especially Scots pine, silver and downy birch, black alder) must be preceded by a stand−initiating (stand−replacing) disturbance, leading to total or partial, but heavy, destruction of the currently existing stand. At the moment, it would be difficult to predict, however, if and when such a disturbance will affect the stands under investigation. Thus, we predict that in the nearest future at least, the state of overall demographic unbalance will continue or even increase.

6

Struktura i dynamika wielogeneracyjnych starodrzewów sosnowych występujących w obszarach ochrony ścisłej Kaliszki i Sieraków w Kampinoskim Parku Narodowym. Część 1. Zróżnicowanie gatunkowe, zagęszczenie i pierśnicowe pole przekroju

51%

Brzeziecki B. , Zajaczkowski J. , Olszewski A. , Bolibok L. , Andrzejczyk T. , Bielak K. , Buraczyk W. , Drozdowski S. , Gawron L. , Jastrzebowski S. , Szeligowski H. , Zybura H.

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2020

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tom 164

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nr 05

EN

The paper describes changes, which took place over the last 30 years in old−growth forest stands occupying two permanent research plots, established in the Kaliszki and Sieraków strict protection areas in the Kampinos National Park (central Poland). Both plots have a form of ecological transects. The Kaliszki plot is 20 m wide and 700 m long (1.40 ha), while the Sieraków plot (total area of 2.56 ha) consists of two parts: main (40×460 m) and side (40×180 m) transect. In the Kaliszki plot, the stand measurements were conducted in 1993, 2007, and 2017, while in the Sieraków plot – in 1989, 1994, 2006, and 2017. For every tree with breast height diameter (DBH) ≥5 cm, species identity, DBH and spatial coordinates were determined. Starting from the second census, all trees which had died (‘losses’), as well as trees which exceeded the DBH threshold (‘gains’) since the previous record were noted, as well. The major tree species occurring on sample plots are Scots pine (Pinus sylvestris), pedunculate oak (Quercus robur), silver and downy birch (Betula sp.), and black alder (Alnus glutinosa). During the study period, the overall tree density declined by ca. 50%. The diminishing trends occurred for all dominant tree species. In contrast to major, dominant tree species, the demographic status of a group of minor tree species (lime, hornbeam and maple) was much more stable. One may even speak about some expansion in this case. Particularly, hornbeam density increased rapidly in the period 2006−2017 in some areas of the main transect located in the Sieraków plot. The future studies will show if this tendency will be maintained and will include other regions of sample plots. Assuming a lack of significant disturbances, one may expect that the stands growing on research plots will rather slowly change in the nearest future. Most dynamics will have a quantitative and not qualitative character. One may anticipate, for example, a growing role of pedunculate oak at the expense of Scots pine, however, considering that the two species are rather long−living, they will probably for a long time keep their dominant roles in the stand canopies.

7

Wieloletnia dynamika starodrzewów w zagospodarowanej części Puszczy Białowieskiej: gatunki ekspansywne i ustępujące

51%

Drozdowski S. , Brzeziecki B. , Zybura H. , Zybura B. , Gawron L. , Buraczyk W. , Zajaczkowski J. , Bolibok L. , Szeligowski H. , Bielak K. , Widawska Z.

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nr 09